2 # (C) Copyright 2000 - 2013
3 # Wolfgang Denk, DENX Software Engineering, wd@denx.de.
5 # SPDX-License-Identifier: GPL-2.0+
11 This directory contains the source code for U-Boot, a boot loader for
12 Embedded boards based on PowerPC, ARM, MIPS and several other
13 processors, which can be installed in a boot ROM and used to
14 initialize and test the hardware or to download and run application
17 The development of U-Boot is closely related to Linux: some parts of
18 the source code originate in the Linux source tree, we have some
19 header files in common, and special provision has been made to
20 support booting of Linux images.
22 Some attention has been paid to make this software easily
23 configurable and extendable. For instance, all monitor commands are
24 implemented with the same call interface, so that it's very easy to
25 add new commands. Also, instead of permanently adding rarely used
26 code (for instance hardware test utilities) to the monitor, you can
27 load and run it dynamically.
33 In general, all boards for which a configuration option exists in the
34 Makefile have been tested to some extent and can be considered
35 "working". In fact, many of them are used in production systems.
37 In case of problems see the CHANGELOG and CREDITS files to find out
38 who contributed the specific port. The boards.cfg file lists board
41 Note: There is no CHANGELOG file in the actual U-Boot source tree;
42 it can be created dynamically from the Git log using:
50 In case you have questions about, problems with or contributions for
51 U-Boot you should send a message to the U-Boot mailing list at
52 <u-boot@lists.denx.de>. There is also an archive of previous traffic
53 on the mailing list - please search the archive before asking FAQ's.
54 Please see http://lists.denx.de/pipermail/u-boot and
55 http://dir.gmane.org/gmane.comp.boot-loaders.u-boot
58 Where to get source code:
59 =========================
61 The U-Boot source code is maintained in the git repository at
62 git://www.denx.de/git/u-boot.git ; you can browse it online at
63 http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary
65 The "snapshot" links on this page allow you to download tarballs of
66 any version you might be interested in. Official releases are also
67 available for FTP download from the ftp://ftp.denx.de/pub/u-boot/
70 Pre-built (and tested) images are available from
71 ftp://ftp.denx.de/pub/u-boot/images/
77 - start from 8xxrom sources
78 - create PPCBoot project (http://sourceforge.net/projects/ppcboot)
80 - make it easier to add custom boards
81 - make it possible to add other [PowerPC] CPUs
82 - extend functions, especially:
83 * Provide extended interface to Linux boot loader
86 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot
87 - create ARMBoot project (http://sourceforge.net/projects/armboot)
88 - add other CPU families (starting with ARM)
89 - create U-Boot project (http://sourceforge.net/projects/u-boot)
90 - current project page: see http://www.denx.de/wiki/U-Boot
96 The "official" name of this project is "Das U-Boot". The spelling
97 "U-Boot" shall be used in all written text (documentation, comments
98 in source files etc.). Example:
100 This is the README file for the U-Boot project.
102 File names etc. shall be based on the string "u-boot". Examples:
104 include/asm-ppc/u-boot.h
106 #include <asm/u-boot.h>
108 Variable names, preprocessor constants etc. shall be either based on
109 the string "u_boot" or on "U_BOOT". Example:
111 U_BOOT_VERSION u_boot_logo
112 IH_OS_U_BOOT u_boot_hush_start
118 Starting with the release in October 2008, the names of the releases
119 were changed from numerical release numbers without deeper meaning
120 into a time stamp based numbering. Regular releases are identified by
121 names consisting of the calendar year and month of the release date.
122 Additional fields (if present) indicate release candidates or bug fix
123 releases in "stable" maintenance trees.
126 U-Boot v2009.11 - Release November 2009
127 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree
128 U-Boot v2010.09-rc1 - Release candiate 1 for September 2010 release
134 /arch Architecture specific files
135 /arc Files generic to ARC architecture
136 /cpu CPU specific files
137 /arc700 Files specific to ARC 700 CPUs
138 /lib Architecture specific library files
139 /arm Files generic to ARM architecture
140 /cpu CPU specific files
141 /arm720t Files specific to ARM 720 CPUs
142 /arm920t Files specific to ARM 920 CPUs
143 /at91 Files specific to Atmel AT91RM9200 CPU
144 /imx Files specific to Freescale MC9328 i.MX CPUs
145 /s3c24x0 Files specific to Samsung S3C24X0 CPUs
146 /arm926ejs Files specific to ARM 926 CPUs
147 /arm1136 Files specific to ARM 1136 CPUs
148 /pxa Files specific to Intel XScale PXA CPUs
149 /sa1100 Files specific to Intel StrongARM SA1100 CPUs
150 /lib Architecture specific library files
151 /avr32 Files generic to AVR32 architecture
152 /cpu CPU specific files
153 /lib Architecture specific library files
154 /blackfin Files generic to Analog Devices Blackfin architecture
155 /cpu CPU specific files
156 /lib Architecture specific library files
157 /m68k Files generic to m68k architecture
158 /cpu CPU specific files
159 /mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs
160 /mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs
161 /mcf532x Files specific to Freescale ColdFire MCF5329 CPUs
162 /mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs
163 /mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs
164 /lib Architecture specific library files
165 /microblaze Files generic to microblaze architecture
166 /cpu CPU specific files
167 /lib Architecture specific library files
168 /mips Files generic to MIPS architecture
169 /cpu CPU specific files
170 /mips32 Files specific to MIPS32 CPUs
171 /mips64 Files specific to MIPS64 CPUs
172 /lib Architecture specific library files
173 /nds32 Files generic to NDS32 architecture
174 /cpu CPU specific files
175 /n1213 Files specific to Andes Technology N1213 CPUs
176 /lib Architecture specific library files
177 /nios2 Files generic to Altera NIOS2 architecture
178 /cpu CPU specific files
179 /lib Architecture specific library files
180 /openrisc Files generic to OpenRISC architecture
181 /cpu CPU specific files
182 /lib Architecture specific library files
183 /powerpc Files generic to PowerPC architecture
184 /cpu CPU specific files
185 /mpc5xx Files specific to Freescale MPC5xx CPUs
186 /mpc5xxx Files specific to Freescale MPC5xxx CPUs
187 /mpc8xx Files specific to Freescale MPC8xx CPUs
188 /mpc8260 Files specific to Freescale MPC8260 CPUs
189 /mpc85xx Files specific to Freescale MPC85xx CPUs
190 /ppc4xx Files specific to AMCC PowerPC 4xx CPUs
191 /lib Architecture specific library files
192 /sh Files generic to SH architecture
193 /cpu CPU specific files
194 /sh2 Files specific to sh2 CPUs
195 /sh3 Files specific to sh3 CPUs
196 /sh4 Files specific to sh4 CPUs
197 /lib Architecture specific library files
198 /sparc Files generic to SPARC architecture
199 /cpu CPU specific files
200 /leon2 Files specific to Gaisler LEON2 SPARC CPU
201 /leon3 Files specific to Gaisler LEON3 SPARC CPU
202 /lib Architecture specific library files
203 /x86 Files generic to x86 architecture
204 /cpu CPU specific files
205 /lib Architecture specific library files
206 /api Machine/arch independent API for external apps
207 /board Board dependent files
208 /common Misc architecture independent functions
209 /disk Code for disk drive partition handling
210 /doc Documentation (don't expect too much)
211 /drivers Commonly used device drivers
212 /dts Contains Makefile for building internal U-Boot fdt.
213 /examples Example code for standalone applications, etc.
214 /fs Filesystem code (cramfs, ext2, jffs2, etc.)
215 /include Header Files
216 /lib Files generic to all architectures
217 /libfdt Library files to support flattened device trees
218 /lzma Library files to support LZMA decompression
219 /lzo Library files to support LZO decompression
221 /post Power On Self Test
222 /spl Secondary Program Loader framework
223 /tools Tools to build S-Record or U-Boot images, etc.
225 Software Configuration:
226 =======================
228 Configuration is usually done using C preprocessor defines; the
229 rationale behind that is to avoid dead code whenever possible.
231 There are two classes of configuration variables:
233 * Configuration _OPTIONS_:
234 These are selectable by the user and have names beginning with
237 * Configuration _SETTINGS_:
238 These depend on the hardware etc. and should not be meddled with if
239 you don't know what you're doing; they have names beginning with
242 Later we will add a configuration tool - probably similar to or even
243 identical to what's used for the Linux kernel. Right now, we have to
244 do the configuration by hand, which means creating some symbolic
245 links and editing some configuration files. We use the TQM8xxL boards
249 Selection of Processor Architecture and Board Type:
250 ---------------------------------------------------
252 For all supported boards there are ready-to-use default
253 configurations available; just type "make <board_name>_defconfig".
255 Example: For a TQM823L module type:
258 make TQM823L_defconfig
260 For the Cogent platform, you need to specify the CPU type as well;
261 e.g. "make cogent_mpc8xx_defconfig". And also configure the cogent
262 directory according to the instructions in cogent/README.
268 U-Boot can be built natively to run on a Linux host using the 'sandbox'
269 board. This allows feature development which is not board- or architecture-
270 specific to be undertaken on a native platform. The sandbox is also used to
271 run some of U-Boot's tests.
273 See board/sandbox/README.sandbox for more details.
276 Board Initialisation Flow:
277 --------------------------
279 This is the intended start-up flow for boards. This should apply for both
280 SPL and U-Boot proper (i.e. they both follow the same rules). At present SPL
281 mostly uses a separate code path, but the funtion names and roles of each
282 function are the same. Some boards or architectures may not conform to this.
283 At least most ARM boards which use CONFIG_SPL_FRAMEWORK conform to this.
285 Execution starts with start.S with three functions called during init after
286 that. The purpose and limitations of each is described below.
289 - purpose: essential init to permit execution to reach board_init_f()
290 - no global_data or BSS
291 - there is no stack (ARMv7 may have one but it will soon be removed)
292 - must not set up SDRAM or use console
293 - must only do the bare minimum to allow execution to continue to
295 - this is almost never needed
296 - return normally from this function
299 - purpose: set up the machine ready for running board_init_r():
300 i.e. SDRAM and serial UART
301 - global_data is available
303 - BSS is not available, so you cannot use global/static variables,
304 only stack variables and global_data
306 Non-SPL-specific notes:
307 - dram_init() is called to set up DRAM. If already done in SPL this
311 - you can override the entire board_init_f() function with your own
313 - preloader_console_init() can be called here in extremis
314 - should set up SDRAM, and anything needed to make the UART work
315 - these is no need to clear BSS, it will be done by crt0.S
316 - must return normally from this function (don't call board_init_r()
319 Here the BSS is cleared. For SPL, if CONFIG_SPL_STACK_R is defined, then at
320 this point the stack and global_data are relocated to below
321 CONFIG_SPL_STACK_R_ADDR. For non-SPL, U-Boot is relocated to run at the top of
325 - purpose: main execution, common code
326 - global_data is available
328 - BSS is available, all static/global variables can be used
329 - execution eventually continues to main_loop()
331 Non-SPL-specific notes:
332 - U-Boot is relocated to the top of memory and is now running from
336 - stack is optionally in SDRAM, if CONFIG_SPL_STACK_R is defined and
337 CONFIG_SPL_STACK_R_ADDR points into SDRAM
338 - preloader_console_init() can be called here - typically this is
339 done by defining CONFIG_SPL_BOARD_INIT and then supplying a
340 spl_board_init() function containing this call
341 - loads U-Boot or (in falcon mode) Linux
345 Configuration Options:
346 ----------------------
348 Configuration depends on the combination of board and CPU type; all
349 such information is kept in a configuration file
350 "include/configs/<board_name>.h".
352 Example: For a TQM823L module, all configuration settings are in
353 "include/configs/TQM823L.h".
356 Many of the options are named exactly as the corresponding Linux
357 kernel configuration options. The intention is to make it easier to
358 build a config tool - later.
361 The following options need to be configured:
363 - CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
365 - Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
367 - CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined)
368 Define exactly one, e.g. CONFIG_ATSTK1002
370 - CPU Module Type: (if CONFIG_COGENT is defined)
371 Define exactly one of
373 --- FIXME --- not tested yet:
374 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
375 CONFIG_CMA287_23, CONFIG_CMA287_50
377 - Motherboard Type: (if CONFIG_COGENT is defined)
378 Define exactly one of
379 CONFIG_CMA101, CONFIG_CMA102
381 - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
382 Define one or more of
385 - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
386 Define one or more of
387 CONFIG_LCD_HEARTBEAT - update a character position on
388 the LCD display every second with
391 - Marvell Family Member
392 CONFIG_SYS_MVFS - define it if you want to enable
393 multiple fs option at one time
394 for marvell soc family
396 - 8xx CPU Options: (if using an MPC8xx CPU)
397 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if
398 get_gclk_freq() cannot work
399 e.g. if there is no 32KHz
400 reference PIT/RTC clock
401 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK
404 - 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
405 CONFIG_SYS_8xx_CPUCLK_MIN
406 CONFIG_SYS_8xx_CPUCLK_MAX
407 CONFIG_8xx_CPUCLK_DEFAULT
408 See doc/README.MPC866
410 CONFIG_SYS_MEASURE_CPUCLK
412 Define this to measure the actual CPU clock instead
413 of relying on the correctness of the configured
414 values. Mostly useful for board bringup to make sure
415 the PLL is locked at the intended frequency. Note
416 that this requires a (stable) reference clock (32 kHz
417 RTC clock or CONFIG_SYS_8XX_XIN)
419 CONFIG_SYS_DELAYED_ICACHE
421 Define this option if you want to enable the
422 ICache only when Code runs from RAM.
427 Specifies that the core is a 64-bit PowerPC implementation (implements
428 the "64" category of the Power ISA). This is necessary for ePAPR
429 compliance, among other possible reasons.
431 CONFIG_SYS_FSL_TBCLK_DIV
433 Defines the core time base clock divider ratio compared to the
434 system clock. On most PQ3 devices this is 8, on newer QorIQ
435 devices it can be 16 or 32. The ratio varies from SoC to Soc.
437 CONFIG_SYS_FSL_PCIE_COMPAT
439 Defines the string to utilize when trying to match PCIe device
440 tree nodes for the given platform.
442 CONFIG_SYS_PPC_E500_DEBUG_TLB
444 Enables a temporary TLB entry to be used during boot to work
445 around limitations in e500v1 and e500v2 external debugger
446 support. This reduces the portions of the boot code where
447 breakpoints and single stepping do not work. The value of this
448 symbol should be set to the TLB1 entry to be used for this
451 CONFIG_SYS_FSL_ERRATUM_A004510
453 Enables a workaround for erratum A004510. If set,
454 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and
455 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set.
457 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV
458 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional)
460 Defines one or two SoC revisions (low 8 bits of SVR)
461 for which the A004510 workaround should be applied.
463 The rest of SVR is either not relevant to the decision
464 of whether the erratum is present (e.g. p2040 versus
465 p2041) or is implied by the build target, which controls
466 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set.
468 See Freescale App Note 4493 for more information about
471 CONFIG_A003399_NOR_WORKAROUND
472 Enables a workaround for IFC erratum A003399. It is only
473 required during NOR boot.
475 CONFIG_A008044_WORKAROUND
476 Enables a workaround for T1040/T1042 erratum A008044. It is only
477 required during NAND boot and valid for Rev 1.0 SoC revision
479 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY
481 This is the value to write into CCSR offset 0x18600
482 according to the A004510 workaround.
484 CONFIG_SYS_FSL_DSP_DDR_ADDR
485 This value denotes start offset of DDR memory which is
486 connected exclusively to the DSP cores.
488 CONFIG_SYS_FSL_DSP_M2_RAM_ADDR
489 This value denotes start offset of M2 memory
490 which is directly connected to the DSP core.
492 CONFIG_SYS_FSL_DSP_M3_RAM_ADDR
493 This value denotes start offset of M3 memory which is directly
494 connected to the DSP core.
496 CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT
497 This value denotes start offset of DSP CCSR space.
499 CONFIG_SYS_FSL_SINGLE_SOURCE_CLK
500 Single Source Clock is clocking mode present in some of FSL SoC's.
501 In this mode, a single differential clock is used to supply
502 clocks to the sysclock, ddrclock and usbclock.
504 CONFIG_SYS_CPC_REINIT_F
505 This CONFIG is defined when the CPC is configured as SRAM at the
506 time of U-boot entry and is required to be re-initialized.
509 Indicates this SoC supports deep sleep feature. If deep sleep is
510 supported, core will start to execute uboot when wakes up.
512 - Generic CPU options:
513 CONFIG_SYS_GENERIC_GLOBAL_DATA
514 Defines global data is initialized in generic board board_init_f().
515 If this macro is defined, global data is created and cleared in
516 generic board board_init_f(). Without this macro, architecture/board
517 should initialize global data before calling board_init_f().
519 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN
521 Defines the endianess of the CPU. Implementation of those
522 values is arch specific.
525 Freescale DDR driver in use. This type of DDR controller is
526 found in mpc83xx, mpc85xx, mpc86xx as well as some ARM core
529 CONFIG_SYS_FSL_DDR_ADDR
530 Freescale DDR memory-mapped register base.
532 CONFIG_SYS_FSL_DDR_EMU
533 Specify emulator support for DDR. Some DDR features such as
534 deskew training are not available.
536 CONFIG_SYS_FSL_DDRC_GEN1
537 Freescale DDR1 controller.
539 CONFIG_SYS_FSL_DDRC_GEN2
540 Freescale DDR2 controller.
542 CONFIG_SYS_FSL_DDRC_GEN3
543 Freescale DDR3 controller.
545 CONFIG_SYS_FSL_DDRC_GEN4
546 Freescale DDR4 controller.
548 CONFIG_SYS_FSL_DDRC_ARM_GEN3
549 Freescale DDR3 controller for ARM-based SoCs.
552 Board config to use DDR1. It can be enabled for SoCs with
553 Freescale DDR1 or DDR2 controllers, depending on the board
557 Board config to use DDR2. It can be eanbeld for SoCs with
558 Freescale DDR2 or DDR3 controllers, depending on the board
562 Board config to use DDR3. It can be enabled for SoCs with
563 Freescale DDR3 or DDR3L controllers.
566 Board config to use DDR3L. It can be enabled for SoCs with
570 Board config to use DDR4. It can be enabled for SoCs with
573 CONFIG_SYS_FSL_IFC_BE
574 Defines the IFC controller register space as Big Endian
576 CONFIG_SYS_FSL_IFC_LE
577 Defines the IFC controller register space as Little Endian
579 CONFIG_SYS_FSL_PBL_PBI
580 It enables addition of RCW (Power on reset configuration) in built image.
581 Please refer doc/README.pblimage for more details
583 CONFIG_SYS_FSL_PBL_RCW
584 It adds PBI(pre-boot instructions) commands in u-boot build image.
585 PBI commands can be used to configure SoC before it starts the execution.
586 Please refer doc/README.pblimage for more details
589 It adds a target to create boot binary having SPL binary in PBI format
590 concatenated with u-boot binary.
592 CONFIG_SYS_FSL_DDR_BE
593 Defines the DDR controller register space as Big Endian
595 CONFIG_SYS_FSL_DDR_LE
596 Defines the DDR controller register space as Little Endian
598 CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY
599 Physical address from the view of DDR controllers. It is the
600 same as CONFIG_SYS_DDR_SDRAM_BASE for all Power SoCs. But
601 it could be different for ARM SoCs.
603 CONFIG_SYS_FSL_DDR_INTLV_256B
604 DDR controller interleaving on 256-byte. This is a special
605 interleaving mode, handled by Dickens for Freescale layerscape
608 CONFIG_SYS_FSL_DDR_MAIN_NUM_CTRLS
609 Number of controllers used as main memory.
611 CONFIG_SYS_FSL_OTHER_DDR_NUM_CTRLS
612 Number of controllers used for other than main memory.
614 CONFIG_SYS_FSL_SEC_BE
615 Defines the SEC controller register space as Big Endian
617 CONFIG_SYS_FSL_SEC_LE
618 Defines the SEC controller register space as Little Endian
620 - Intel Monahans options:
621 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO
623 Defines the Monahans run mode to oscillator
624 ratio. Valid values are 8, 16, 24, 31. The core
625 frequency is this value multiplied by 13 MHz.
627 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO
629 Defines the Monahans turbo mode to oscillator
630 ratio. Valid values are 1 (default if undefined) and
631 2. The core frequency as calculated above is multiplied
635 CONFIG_SYS_INIT_SP_OFFSET
637 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack
638 pointer. This is needed for the temporary stack before
641 CONFIG_SYS_MIPS_CACHE_MODE
643 Cache operation mode for the MIPS CPU.
644 See also arch/mips/include/asm/mipsregs.h.
646 CONF_CM_CACHABLE_NO_WA
649 CONF_CM_CACHABLE_NONCOHERENT
653 CONF_CM_CACHABLE_ACCELERATED
655 CONFIG_SYS_XWAY_EBU_BOOTCFG
657 Special option for Lantiq XWAY SoCs for booting from NOR flash.
658 See also arch/mips/cpu/mips32/start.S.
660 CONFIG_XWAY_SWAP_BYTES
662 Enable compilation of tools/xway-swap-bytes needed for Lantiq
663 XWAY SoCs for booting from NOR flash. The U-Boot image needs to
664 be swapped if a flash programmer is used.
667 CONFIG_SYS_EXCEPTION_VECTORS_HIGH
669 Select high exception vectors of the ARM core, e.g., do not
670 clear the V bit of the c1 register of CP15.
672 CONFIG_SYS_THUMB_BUILD
674 Use this flag to build U-Boot using the Thumb instruction
675 set for ARM architectures. Thumb instruction set provides
676 better code density. For ARM architectures that support
677 Thumb2 this flag will result in Thumb2 code generated by
680 CONFIG_ARM_ERRATA_716044
681 CONFIG_ARM_ERRATA_742230
682 CONFIG_ARM_ERRATA_743622
683 CONFIG_ARM_ERRATA_751472
684 CONFIG_ARM_ERRATA_794072
685 CONFIG_ARM_ERRATA_761320
687 If set, the workarounds for these ARM errata are applied early
688 during U-Boot startup. Note that these options force the
689 workarounds to be applied; no CPU-type/version detection
690 exists, unlike the similar options in the Linux kernel. Do not
691 set these options unless they apply!
694 Generic timer clock source frequency.
696 COUNTER_FREQUENCY_REAL
697 Generic timer clock source frequency if the real clock is
698 different from COUNTER_FREQUENCY, and can only be determined
701 NOTE: The following can be machine specific errata. These
702 do have ability to provide rudimentary version and machine
703 specific checks, but expect no product checks.
704 CONFIG_ARM_ERRATA_798870
705 CONFIG_ARM_ERRATA_801819
708 CONFIG_TEGRA_SUPPORT_NON_SECURE
710 Support executing U-Boot in non-secure (NS) mode. Certain
711 impossible actions will be skipped if the CPU is in NS mode,
712 such as ARM architectural timer initialization.
715 Driver model is a new framework for devices in U-Boot
716 introduced in early 2014. U-Boot is being progressively
717 moved over to this. It offers a consistent device structure,
718 supports grouping devices into classes and has built-in
719 handling of platform data and device tree.
721 To enable transition to driver model in a relatively
722 painful fashion, each subsystem can be independently
723 switched between the legacy/ad-hoc approach and the new
724 driver model using the options below. Also, many uclass
725 interfaces include compatibility features which may be
726 removed once the conversion of that subsystem is complete.
727 As a result, the API provided by the subsystem may in fact
728 not change with driver model.
730 See doc/driver-model/README.txt for more information.
734 Enable driver model. This brings in the core support,
735 including scanning of platform data on start-up. If
736 CONFIG_OF_CONTROL is enabled, the device tree will be
737 scanned also when available.
741 Enable driver model test commands. These allow you to print
742 out the driver model tree and the uclasses.
746 Enable some demo devices and the 'demo' command. These are
747 really only useful for playing around while trying to
748 understand driver model in sandbox.
752 Enable driver model in SPL. You will need to provide a
753 suitable malloc() implementation. If you are not using the
754 full malloc() enabled by CONFIG_SYS_SPL_MALLOC_START,
755 consider using CONFIG_SYS_MALLOC_SIMPLE. In that case you
756 must provide CONFIG_SYS_MALLOC_F_LEN to set the size.
757 In most cases driver model will only allocate a few uclasses
758 and devices in SPL, so 1KB should be enable. See
759 CONFIG_SYS_MALLOC_F_LEN for more details on how to enable
764 Enable driver model for serial. This replaces
765 drivers/serial/serial.c with the serial uclass, which
766 implements serial_putc() etc. The uclass interface is
767 defined in include/serial.h.
771 Enable driver model for GPIO access. The standard GPIO
772 interface (gpio_get_value(), etc.) is then implemented by
773 the GPIO uclass. Drivers provide methods to query the
774 particular GPIOs that they provide. The uclass interface
775 is defined in include/asm-generic/gpio.h.
779 Enable driver model for SPI. The SPI slave interface
780 (spi_setup_slave(), spi_xfer(), etc.) is then implemented by
781 the SPI uclass. Drivers provide methods to access the SPI
782 buses that they control. The uclass interface is defined in
783 include/spi.h. The existing spi_slave structure is attached
784 as 'parent data' to every slave on each bus. Slaves
785 typically use driver-private data instead of extending the
790 Enable driver model for SPI flash. This SPI flash interface
791 (spi_flash_probe(), spi_flash_write(), etc.) is then
792 implemented by the SPI flash uclass. There is one standard
793 SPI flash driver which knows how to probe most chips
794 supported by U-Boot. The uclass interface is defined in
795 include/spi_flash.h, but is currently fully compatible
796 with the old interface to avoid confusion and duplication
797 during the transition parent. SPI and SPI flash must be
798 enabled together (it is not possible to use driver model
799 for one and not the other).
803 Enable driver model for the Chrome OS EC interface. This
804 allows the cros_ec SPI driver to operate with CONFIG_DM_SPI
805 but otherwise makes few changes. Since cros_ec also supports
806 I2C and LPC (which don't support driver model yet), a full
807 conversion is not yet possible.
810 ** Code size options: The following options are enabled by
811 default except in SPL. Enable them explicitly to get these
816 Enable the dm_warn() function. This can use up quite a bit
817 of space for its strings.
821 Enable registering a serial device with the stdio library.
823 CONFIG_DM_DEVICE_REMOVE
825 Enable removing of devices.
827 - Linux Kernel Interface:
830 U-Boot stores all clock information in Hz
831 internally. For binary compatibility with older Linux
832 kernels (which expect the clocks passed in the
833 bd_info data to be in MHz) the environment variable
834 "clocks_in_mhz" can be defined so that U-Boot
835 converts clock data to MHZ before passing it to the
837 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
838 "clocks_in_mhz=1" is automatically included in the
841 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
843 When transferring memsize parameter to Linux, some versions
844 expect it to be in bytes, others in MB.
845 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
849 New kernel versions are expecting firmware settings to be
850 passed using flattened device trees (based on open firmware
854 * New libfdt-based support
855 * Adds the "fdt" command
856 * The bootm command automatically updates the fdt
858 OF_CPU - The proper name of the cpus node (only required for
859 MPC512X and MPC5xxx based boards).
860 OF_SOC - The proper name of the soc node (only required for
861 MPC512X and MPC5xxx based boards).
862 OF_TBCLK - The timebase frequency.
863 OF_STDOUT_PATH - The path to the console device
865 boards with QUICC Engines require OF_QE to set UCC MAC
868 CONFIG_OF_BOARD_SETUP
870 Board code has addition modification that it wants to make
871 to the flat device tree before handing it off to the kernel
873 CONFIG_OF_SYSTEM_SETUP
875 Other code has addition modification that it wants to make
876 to the flat device tree before handing it off to the kernel.
877 This causes ft_system_setup() to be called before booting
882 This define fills in the correct boot CPU in the boot
883 param header, the default value is zero if undefined.
887 U-Boot can detect if an IDE device is present or not.
888 If not, and this new config option is activated, U-Boot
889 removes the ATA node from the DTS before booting Linux,
890 so the Linux IDE driver does not probe the device and
891 crash. This is needed for buggy hardware (uc101) where
892 no pull down resistor is connected to the signal IDE5V_DD7.
894 CONFIG_MACH_TYPE [relevant for ARM only][mandatory]
896 This setting is mandatory for all boards that have only one
897 machine type and must be used to specify the machine type
898 number as it appears in the ARM machine registry
899 (see http://www.arm.linux.org.uk/developer/machines/).
900 Only boards that have multiple machine types supported
901 in a single configuration file and the machine type is
902 runtime discoverable, do not have to use this setting.
904 - vxWorks boot parameters:
906 bootvx constructs a valid bootline using the following
907 environments variables: bootfile, ipaddr, serverip, hostname.
908 It loads the vxWorks image pointed bootfile.
910 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name
911 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address
912 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server
913 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters
915 CONFIG_SYS_VXWORKS_ADD_PARAMS
917 Add it at the end of the bootline. E.g "u=username pw=secret"
919 Note: If a "bootargs" environment is defined, it will overwride
920 the defaults discussed just above.
922 - Cache Configuration:
923 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot
924 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot
925 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot
927 - Cache Configuration for ARM:
928 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache
930 CONFIG_SYS_PL310_BASE - Physical base address of PL310
931 controller register space
936 Define this if you want support for Amba PrimeCell PL010 UARTs.
940 Define this if you want support for Amba PrimeCell PL011 UARTs.
944 If you have Amba PrimeCell PL011 UARTs, set this variable to
945 the clock speed of the UARTs.
949 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
950 define this to a list of base addresses for each (supported)
951 port. See e.g. include/configs/versatile.h
953 CONFIG_PL011_SERIAL_RLCR
955 Some vendor versions of PL011 serial ports (e.g. ST-Ericsson U8500)
956 have separate receive and transmit line control registers. Set
957 this variable to initialize the extra register.
959 CONFIG_PL011_SERIAL_FLUSH_ON_INIT
961 On some platforms (e.g. U8500) U-Boot is loaded by a second stage
962 boot loader that has already initialized the UART. Define this
963 variable to flush the UART at init time.
965 CONFIG_SERIAL_HW_FLOW_CONTROL
967 Define this variable to enable hw flow control in serial driver.
968 Current user of this option is drivers/serial/nsl16550.c driver
971 Depending on board, define exactly one serial port
972 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
973 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
974 console by defining CONFIG_8xx_CONS_NONE
976 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
977 port routines must be defined elsewhere
978 (i.e. serial_init(), serial_getc(), ...)
981 Enables console device for a color framebuffer. Needs following
982 defines (cf. smiLynxEM, i8042)
983 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
985 VIDEO_HW_RECTFILL graphic chip supports
988 VIDEO_HW_BITBLT graphic chip supports
989 bit-blit (cf. smiLynxEM)
990 VIDEO_VISIBLE_COLS visible pixel columns
992 VIDEO_VISIBLE_ROWS visible pixel rows
993 VIDEO_PIXEL_SIZE bytes per pixel
994 VIDEO_DATA_FORMAT graphic data format
995 (0-5, cf. cfb_console.c)
996 VIDEO_FB_ADRS framebuffer address
997 VIDEO_KBD_INIT_FCT keyboard int fct
998 (i.e. i8042_kbd_init())
999 VIDEO_TSTC_FCT test char fct
1001 VIDEO_GETC_FCT get char fct
1003 CONFIG_CONSOLE_CURSOR cursor drawing on/off
1004 (requires blink timer
1006 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
1007 CONFIG_CONSOLE_TIME display time/date info in
1009 (requires CONFIG_CMD_DATE)
1010 CONFIG_VIDEO_LOGO display Linux logo in
1012 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
1013 linux_logo.h for logo.
1014 Requires CONFIG_VIDEO_LOGO
1015 CONFIG_CONSOLE_EXTRA_INFO
1016 additional board info beside
1019 When CONFIG_CFB_CONSOLE_ANSI is defined, console will support
1020 a limited number of ANSI escape sequences (cursor control,
1021 erase functions and limited graphics rendition control).
1023 When CONFIG_CFB_CONSOLE is defined, video console is
1024 default i/o. Serial console can be forced with
1025 environment 'console=serial'.
1027 When CONFIG_SILENT_CONSOLE is defined, all console
1028 messages (by U-Boot and Linux!) can be silenced with
1029 the "silent" environment variable. See
1030 doc/README.silent for more information.
1032 CONFIG_SYS_CONSOLE_BG_COL: define the backgroundcolor, default
1034 CONFIG_SYS_CONSOLE_FG_COL: define the foregroundcolor, default
1038 CONFIG_BAUDRATE - in bps
1039 Select one of the baudrates listed in
1040 CONFIG_SYS_BAUDRATE_TABLE, see below.
1041 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale
1043 - Console Rx buffer length
1044 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define
1045 the maximum receive buffer length for the SMC.
1046 This option is actual only for 82xx and 8xx possible.
1047 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE
1048 must be defined, to setup the maximum idle timeout for
1051 - Pre-Console Buffer:
1052 Prior to the console being initialised (i.e. serial UART
1053 initialised etc) all console output is silently discarded.
1054 Defining CONFIG_PRE_CONSOLE_BUFFER will cause U-Boot to
1055 buffer any console messages prior to the console being
1056 initialised to a buffer of size CONFIG_PRE_CON_BUF_SZ
1057 bytes located at CONFIG_PRE_CON_BUF_ADDR. The buffer is
1058 a circular buffer, so if more than CONFIG_PRE_CON_BUF_SZ
1059 bytes are output before the console is initialised, the
1060 earlier bytes are discarded.
1062 Note that when printing the buffer a copy is made on the
1063 stack so CONFIG_PRE_CON_BUF_SZ must fit on the stack.
1065 'Sane' compilers will generate smaller code if
1066 CONFIG_PRE_CON_BUF_SZ is a power of 2
1068 - Safe printf() functions
1069 Define CONFIG_SYS_VSNPRINTF to compile in safe versions of
1070 the printf() functions. These are defined in
1071 include/vsprintf.h and include snprintf(), vsnprintf() and
1072 so on. Code size increase is approximately 300-500 bytes.
1073 If this option is not given then these functions will
1074 silently discard their buffer size argument - this means
1075 you are not getting any overflow checking in this case.
1077 - Boot Delay: CONFIG_BOOTDELAY - in seconds
1078 Delay before automatically booting the default image;
1079 set to -1 to disable autoboot.
1080 set to -2 to autoboot with no delay and not check for abort
1081 (even when CONFIG_ZERO_BOOTDELAY_CHECK is defined).
1083 See doc/README.autoboot for these options that
1084 work with CONFIG_BOOTDELAY. None are required.
1085 CONFIG_BOOT_RETRY_TIME
1086 CONFIG_BOOT_RETRY_MIN
1087 CONFIG_AUTOBOOT_KEYED
1088 CONFIG_AUTOBOOT_PROMPT
1089 CONFIG_AUTOBOOT_DELAY_STR
1090 CONFIG_AUTOBOOT_STOP_STR
1091 CONFIG_ZERO_BOOTDELAY_CHECK
1092 CONFIG_RESET_TO_RETRY
1096 Only needed when CONFIG_BOOTDELAY is enabled;
1097 define a command string that is automatically executed
1098 when no character is read on the console interface
1099 within "Boot Delay" after reset.
1102 This can be used to pass arguments to the bootm
1103 command. The value of CONFIG_BOOTARGS goes into the
1104 environment value "bootargs".
1106 CONFIG_RAMBOOT and CONFIG_NFSBOOT
1107 The value of these goes into the environment as
1108 "ramboot" and "nfsboot" respectively, and can be used
1109 as a convenience, when switching between booting from
1113 CONFIG_BOOTCOUNT_LIMIT
1114 Implements a mechanism for detecting a repeating reboot
1116 http://www.denx.de/wiki/view/DULG/UBootBootCountLimit
1118 CONFIG_BOOTCOUNT_ENV
1119 If no softreset save registers are found on the hardware
1120 "bootcount" is stored in the environment. To prevent a
1121 saveenv on all reboots, the environment variable
1122 "upgrade_available" is used. If "upgrade_available" is
1123 0, "bootcount" is always 0, if "upgrade_available" is
1124 1 "bootcount" is incremented in the environment.
1125 So the Userspace Applikation must set the "upgrade_available"
1126 and "bootcount" variable to 0, if a boot was successfully.
1128 - Pre-Boot Commands:
1131 When this option is #defined, the existence of the
1132 environment variable "preboot" will be checked
1133 immediately before starting the CONFIG_BOOTDELAY
1134 countdown and/or running the auto-boot command resp.
1135 entering interactive mode.
1137 This feature is especially useful when "preboot" is
1138 automatically generated or modified. For an example
1139 see the LWMON board specific code: here "preboot" is
1140 modified when the user holds down a certain
1141 combination of keys on the (special) keyboard when
1144 - Serial Download Echo Mode:
1146 If defined to 1, all characters received during a
1147 serial download (using the "loads" command) are
1148 echoed back. This might be needed by some terminal
1149 emulations (like "cu"), but may as well just take
1150 time on others. This setting #define's the initial
1151 value of the "loads_echo" environment variable.
1153 - Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
1154 CONFIG_KGDB_BAUDRATE
1155 Select one of the baudrates listed in
1156 CONFIG_SYS_BAUDRATE_TABLE, see below.
1158 - Monitor Functions:
1159 Monitor commands can be included or excluded
1160 from the build by using the #include files
1161 <config_cmd_all.h> and #undef'ing unwanted
1162 commands, or adding #define's for wanted commands.
1164 The default command configuration includes all commands
1165 except those marked below with a "*".
1167 CONFIG_CMD_AES AES 128 CBC encrypt/decrypt
1168 CONFIG_CMD_ASKENV * ask for env variable
1169 CONFIG_CMD_BDI bdinfo
1170 CONFIG_CMD_BEDBUG * Include BedBug Debugger
1171 CONFIG_CMD_BMP * BMP support
1172 CONFIG_CMD_BSP * Board specific commands
1173 CONFIG_CMD_BOOTD bootd
1174 CONFIG_CMD_BOOTI * ARM64 Linux kernel Image support
1175 CONFIG_CMD_CACHE * icache, dcache
1176 CONFIG_CMD_CLK * clock command support
1177 CONFIG_CMD_CONSOLE coninfo
1178 CONFIG_CMD_CRC32 * crc32
1179 CONFIG_CMD_DATE * support for RTC, date/time...
1180 CONFIG_CMD_DHCP * DHCP support
1181 CONFIG_CMD_DIAG * Diagnostics
1182 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands
1183 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command
1184 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd
1185 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command
1186 CONFIG_CMD_DTT * Digital Therm and Thermostat
1187 CONFIG_CMD_ECHO echo arguments
1188 CONFIG_CMD_EDITENV edit env variable
1189 CONFIG_CMD_EEPROM * EEPROM read/write support
1190 CONFIG_CMD_ELF * bootelf, bootvx
1191 CONFIG_CMD_ENV_CALLBACK * display details about env callbacks
1192 CONFIG_CMD_ENV_FLAGS * display details about env flags
1193 CONFIG_CMD_ENV_EXISTS * check existence of env variable
1194 CONFIG_CMD_EXPORTENV * export the environment
1195 CONFIG_CMD_EXT2 * ext2 command support
1196 CONFIG_CMD_EXT4 * ext4 command support
1197 CONFIG_CMD_FS_GENERIC * filesystem commands (e.g. load, ls)
1198 that work for multiple fs types
1199 CONFIG_CMD_FS_UUID * Look up a filesystem UUID
1200 CONFIG_CMD_SAVEENV saveenv
1201 CONFIG_CMD_FDC * Floppy Disk Support
1202 CONFIG_CMD_FAT * FAT command support
1203 CONFIG_CMD_FLASH flinfo, erase, protect
1204 CONFIG_CMD_FPGA FPGA device initialization support
1205 CONFIG_CMD_FUSE * Device fuse support
1206 CONFIG_CMD_GETTIME * Get time since boot
1207 CONFIG_CMD_GO * the 'go' command (exec code)
1208 CONFIG_CMD_GREPENV * search environment
1209 CONFIG_CMD_HASH * calculate hash / digest
1210 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control
1211 CONFIG_CMD_I2C * I2C serial bus support
1212 CONFIG_CMD_IDE * IDE harddisk support
1213 CONFIG_CMD_IMI iminfo
1214 CONFIG_CMD_IMLS List all images found in NOR flash
1215 CONFIG_CMD_IMLS_NAND * List all images found in NAND flash
1216 CONFIG_CMD_IMMAP * IMMR dump support
1217 CONFIG_CMD_IOTRACE * I/O tracing for debugging
1218 CONFIG_CMD_IMPORTENV * import an environment
1219 CONFIG_CMD_INI * import data from an ini file into the env
1220 CONFIG_CMD_IRQ * irqinfo
1221 CONFIG_CMD_ITEST Integer/string test of 2 values
1222 CONFIG_CMD_JFFS2 * JFFS2 Support
1223 CONFIG_CMD_KGDB * kgdb
1224 CONFIG_CMD_LDRINFO * ldrinfo (display Blackfin loader)
1225 CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration
1227 CONFIG_CMD_LOADB loadb
1228 CONFIG_CMD_LOADS loads
1229 CONFIG_CMD_MD5SUM * print md5 message digest
1230 (requires CONFIG_CMD_MEMORY and CONFIG_MD5)
1231 CONFIG_CMD_MEMINFO * Display detailed memory information
1232 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
1234 CONFIG_CMD_MEMTEST * mtest
1235 CONFIG_CMD_MISC Misc functions like sleep etc
1236 CONFIG_CMD_MMC * MMC memory mapped support
1237 CONFIG_CMD_MII * MII utility commands
1238 CONFIG_CMD_MTDPARTS * MTD partition support
1239 CONFIG_CMD_NAND * NAND support
1240 CONFIG_CMD_NET bootp, tftpboot, rarpboot
1241 CONFIG_CMD_NFS NFS support
1242 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands
1243 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command
1244 CONFIG_CMD_PCI * pciinfo
1245 CONFIG_CMD_PCMCIA * PCMCIA support
1246 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network
1248 CONFIG_CMD_PORTIO * Port I/O
1249 CONFIG_CMD_READ * Read raw data from partition
1250 CONFIG_CMD_REGINFO * Register dump
1251 CONFIG_CMD_RUN run command in env variable
1252 CONFIG_CMD_SANDBOX * sb command to access sandbox features
1253 CONFIG_CMD_SAVES * save S record dump
1254 CONFIG_CMD_SCSI * SCSI Support
1255 CONFIG_CMD_SDRAM * print SDRAM configuration information
1256 (requires CONFIG_CMD_I2C)
1257 CONFIG_CMD_SETGETDCR Support for DCR Register access
1259 CONFIG_CMD_SF * Read/write/erase SPI NOR flash
1260 CONFIG_CMD_SHA1SUM * print sha1 memory digest
1261 (requires CONFIG_CMD_MEMORY)
1262 CONFIG_CMD_SOFTSWITCH * Soft switch setting command for BF60x
1263 CONFIG_CMD_SOURCE "source" command Support
1264 CONFIG_CMD_SPI * SPI serial bus support
1265 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode
1266 CONFIG_CMD_TFTPPUT * TFTP put command (upload)
1267 CONFIG_CMD_TIME * run command and report execution time (ARM specific)
1268 CONFIG_CMD_TIMER * access to the system tick timer
1269 CONFIG_CMD_USB * USB support
1270 CONFIG_CMD_CDP * Cisco Discover Protocol support
1271 CONFIG_CMD_MFSL * Microblaze FSL support
1272 CONFIG_CMD_XIMG Load part of Multi Image
1273 CONFIG_CMD_UUID * Generate random UUID or GUID string
1275 EXAMPLE: If you want all functions except of network
1276 support you can write:
1278 #include "config_cmd_all.h"
1279 #undef CONFIG_CMD_NET
1282 fdt (flattened device tree) command: CONFIG_OF_LIBFDT
1284 Note: Don't enable the "icache" and "dcache" commands
1285 (configuration option CONFIG_CMD_CACHE) unless you know
1286 what you (and your U-Boot users) are doing. Data
1287 cache cannot be enabled on systems like the 8xx or
1288 8260 (where accesses to the IMMR region must be
1289 uncached), and it cannot be disabled on all other
1290 systems where we (mis-) use the data cache to hold an
1291 initial stack and some data.
1294 XXX - this list needs to get updated!
1296 - Regular expression support:
1298 If this variable is defined, U-Boot is linked against
1299 the SLRE (Super Light Regular Expression) library,
1300 which adds regex support to some commands, as for
1301 example "env grep" and "setexpr".
1305 If this variable is defined, U-Boot will use a device tree
1306 to configure its devices, instead of relying on statically
1307 compiled #defines in the board file. This option is
1308 experimental and only available on a few boards. The device
1309 tree is available in the global data as gd->fdt_blob.
1311 U-Boot needs to get its device tree from somewhere. This can
1312 be done using one of the two options below:
1315 If this variable is defined, U-Boot will embed a device tree
1316 binary in its image. This device tree file should be in the
1317 board directory and called <soc>-<board>.dts. The binary file
1318 is then picked up in board_init_f() and made available through
1319 the global data structure as gd->blob.
1322 If this variable is defined, U-Boot will build a device tree
1323 binary. It will be called u-boot.dtb. Architecture-specific
1324 code will locate it at run-time. Generally this works by:
1326 cat u-boot.bin u-boot.dtb >image.bin
1328 and in fact, U-Boot does this for you, creating a file called
1329 u-boot-dtb.bin which is useful in the common case. You can
1330 still use the individual files if you need something more
1335 If this variable is defined, it enables watchdog
1336 support for the SoC. There must be support in the SoC
1337 specific code for a watchdog. For the 8xx and 8260
1338 CPUs, the SIU Watchdog feature is enabled in the SYPCR
1339 register. When supported for a specific SoC is
1340 available, then no further board specific code should
1341 be needed to use it.
1344 When using a watchdog circuitry external to the used
1345 SoC, then define this variable and provide board
1346 specific code for the "hw_watchdog_reset" function.
1348 CONFIG_AT91_HW_WDT_TIMEOUT
1349 specify the timeout in seconds. default 2 seconds.
1352 CONFIG_VERSION_VARIABLE
1353 If this variable is defined, an environment variable
1354 named "ver" is created by U-Boot showing the U-Boot
1355 version as printed by the "version" command.
1356 Any change to this variable will be reverted at the
1361 When CONFIG_CMD_DATE is selected, the type of the RTC
1362 has to be selected, too. Define exactly one of the
1365 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
1366 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
1367 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC
1368 CONFIG_RTC_MC146818 - use MC146818 RTC
1369 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
1370 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
1371 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
1372 CONFIG_RTC_DS1339 - use Maxim, Inc. DS1339 RTC
1373 CONFIG_RTC_DS164x - use Dallas DS164x RTC
1374 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
1375 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
1376 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
1377 CONFIG_SYS_RV3029_TCR - enable trickle charger on
1380 Note that if the RTC uses I2C, then the I2C interface
1381 must also be configured. See I2C Support, below.
1384 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
1386 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
1387 chip-ngpio pairs that tell the PCA953X driver the number of
1388 pins supported by a particular chip.
1390 Note that if the GPIO device uses I2C, then the I2C interface
1391 must also be configured. See I2C Support, below.
1394 When CONFIG_IO_TRACE is selected, U-Boot intercepts all I/O
1395 accesses and can checksum them or write a list of them out
1396 to memory. See the 'iotrace' command for details. This is
1397 useful for testing device drivers since it can confirm that
1398 the driver behaves the same way before and after a code
1399 change. Currently this is supported on sandbox and arm. To
1400 add support for your architecture, add '#include <iotrace.h>'
1401 to the bottom of arch/<arch>/include/asm/io.h and test.
1403 Example output from the 'iotrace stats' command is below.
1404 Note that if the trace buffer is exhausted, the checksum will
1405 still continue to operate.
1408 Start: 10000000 (buffer start address)
1409 Size: 00010000 (buffer size)
1410 Offset: 00000120 (current buffer offset)
1411 Output: 10000120 (start + offset)
1412 Count: 00000018 (number of trace records)
1413 CRC32: 9526fb66 (CRC32 of all trace records)
1415 - Timestamp Support:
1417 When CONFIG_TIMESTAMP is selected, the timestamp
1418 (date and time) of an image is printed by image
1419 commands like bootm or iminfo. This option is
1420 automatically enabled when you select CONFIG_CMD_DATE .
1422 - Partition Labels (disklabels) Supported:
1423 Zero or more of the following:
1424 CONFIG_MAC_PARTITION Apple's MacOS partition table.
1425 CONFIG_DOS_PARTITION MS Dos partition table, traditional on the
1426 Intel architecture, USB sticks, etc.
1427 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc.
1428 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the
1429 bootloader. Note 2TB partition limit; see
1431 CONFIG_MTD_PARTITIONS Memory Technology Device partition table.
1433 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or
1434 CONFIG_CMD_SCSI) you must configure support for at
1435 least one non-MTD partition type as well.
1438 CONFIG_IDE_RESET_ROUTINE - this is defined in several
1439 board configurations files but used nowhere!
1441 CONFIG_IDE_RESET - is this is defined, IDE Reset will
1442 be performed by calling the function
1443 ide_set_reset(int reset)
1444 which has to be defined in a board specific file
1449 Set this to enable ATAPI support.
1454 Set this to enable support for disks larger than 137GB
1455 Also look at CONFIG_SYS_64BIT_LBA.
1456 Whithout these , LBA48 support uses 32bit variables and will 'only'
1457 support disks up to 2.1TB.
1459 CONFIG_SYS_64BIT_LBA:
1460 When enabled, makes the IDE subsystem use 64bit sector addresses.
1464 At the moment only there is only support for the
1465 SYM53C8XX SCSI controller; define
1466 CONFIG_SCSI_SYM53C8XX to enable it.
1468 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
1469 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
1470 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
1471 maximum numbers of LUNs, SCSI ID's and target
1473 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
1475 The environment variable 'scsidevs' is set to the number of
1476 SCSI devices found during the last scan.
1478 - NETWORK Support (PCI):
1480 Support for Intel 8254x/8257x gigabit chips.
1483 Utility code for direct access to the SPI bus on Intel 8257x.
1484 This does not do anything useful unless you set at least one
1485 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC.
1487 CONFIG_E1000_SPI_GENERIC
1488 Allow generic access to the SPI bus on the Intel 8257x, for
1489 example with the "sspi" command.
1492 Management command for E1000 devices. When used on devices
1493 with SPI support you can reprogram the EEPROM from U-Boot.
1496 Support for Intel 82557/82559/82559ER chips.
1497 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
1498 write routine for first time initialisation.
1501 Support for Digital 2114x chips.
1502 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
1503 modem chip initialisation (KS8761/QS6611).
1506 Support for National dp83815 chips.
1509 Support for National dp8382[01] gigabit chips.
1511 - NETWORK Support (other):
1513 CONFIG_DRIVER_AT91EMAC
1514 Support for AT91RM9200 EMAC.
1517 Define this to use reduced MII inteface
1519 CONFIG_DRIVER_AT91EMAC_QUIET
1520 If this defined, the driver is quiet.
1521 The driver doen't show link status messages.
1523 CONFIG_CALXEDA_XGMAC
1524 Support for the Calxeda XGMAC device
1527 Support for SMSC's LAN91C96 chips.
1529 CONFIG_LAN91C96_BASE
1530 Define this to hold the physical address
1531 of the LAN91C96's I/O space
1533 CONFIG_LAN91C96_USE_32_BIT
1534 Define this to enable 32 bit addressing
1537 Support for SMSC's LAN91C111 chip
1539 CONFIG_SMC91111_BASE
1540 Define this to hold the physical address
1541 of the device (I/O space)
1543 CONFIG_SMC_USE_32_BIT
1544 Define this if data bus is 32 bits
1546 CONFIG_SMC_USE_IOFUNCS
1547 Define this to use i/o functions instead of macros
1548 (some hardware wont work with macros)
1550 CONFIG_DRIVER_TI_EMAC
1551 Support for davinci emac
1553 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT
1554 Define this if you have more then 3 PHYs.
1557 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
1559 CONFIG_FTGMAC100_EGIGA
1560 Define this to use GE link update with gigabit PHY.
1561 Define this if FTGMAC100 is connected to gigabit PHY.
1562 If your system has 10/100 PHY only, it might not occur
1563 wrong behavior. Because PHY usually return timeout or
1564 useless data when polling gigabit status and gigabit
1565 control registers. This behavior won't affect the
1566 correctnessof 10/100 link speed update.
1569 Support for SMSC's LAN911x and LAN921x chips
1572 Define this to hold the physical address
1573 of the device (I/O space)
1575 CONFIG_SMC911X_32_BIT
1576 Define this if data bus is 32 bits
1578 CONFIG_SMC911X_16_BIT
1579 Define this if data bus is 16 bits. If your processor
1580 automatically converts one 32 bit word to two 16 bit
1581 words you may also try CONFIG_SMC911X_32_BIT.
1584 Support for Renesas on-chip Ethernet controller
1586 CONFIG_SH_ETHER_USE_PORT
1587 Define the number of ports to be used
1589 CONFIG_SH_ETHER_PHY_ADDR
1590 Define the ETH PHY's address
1592 CONFIG_SH_ETHER_CACHE_WRITEBACK
1593 If this option is set, the driver enables cache flush.
1597 Support for PWM modul on the imx6.
1601 Support TPM devices.
1604 Support for i2c bus TPM devices. Only one device
1605 per system is supported at this time.
1607 CONFIG_TPM_TIS_I2C_BUS_NUMBER
1608 Define the the i2c bus number for the TPM device
1610 CONFIG_TPM_TIS_I2C_SLAVE_ADDRESS
1611 Define the TPM's address on the i2c bus
1613 CONFIG_TPM_TIS_I2C_BURST_LIMITATION
1614 Define the burst count bytes upper limit
1616 CONFIG_TPM_ATMEL_TWI
1617 Support for Atmel TWI TPM device. Requires I2C support.
1620 Support for generic parallel port TPM devices. Only one device
1621 per system is supported at this time.
1623 CONFIG_TPM_TIS_BASE_ADDRESS
1624 Base address where the generic TPM device is mapped
1625 to. Contemporary x86 systems usually map it at
1629 Add tpm monitor functions.
1630 Requires CONFIG_TPM. If CONFIG_TPM_AUTH_SESSIONS is set, also
1631 provides monitor access to authorized functions.
1634 Define this to enable the TPM support library which provides
1635 functional interfaces to some TPM commands.
1636 Requires support for a TPM device.
1638 CONFIG_TPM_AUTH_SESSIONS
1639 Define this to enable authorized functions in the TPM library.
1640 Requires CONFIG_TPM and CONFIG_SHA1.
1643 At the moment only the UHCI host controller is
1644 supported (PIP405, MIP405, MPC5200); define
1645 CONFIG_USB_UHCI to enable it.
1646 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
1647 and define CONFIG_USB_STORAGE to enable the USB
1650 Supported are USB Keyboards and USB Floppy drives
1652 MPC5200 USB requires additional defines:
1654 for 528 MHz Clock: 0x0001bbbb
1658 for differential drivers: 0x00001000
1659 for single ended drivers: 0x00005000
1660 for differential drivers on PSC3: 0x00000100
1661 for single ended drivers on PSC3: 0x00004100
1662 CONFIG_SYS_USB_EVENT_POLL
1663 May be defined to allow interrupt polling
1664 instead of using asynchronous interrupts
1666 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the
1667 txfilltuning field in the EHCI controller on reset.
1669 CONFIG_USB_DWC2_REG_ADDR the physical CPU address of the DWC2
1670 HW module registers.
1673 Define the below if you wish to use the USB console.
1674 Once firmware is rebuilt from a serial console issue the
1675 command "setenv stdin usbtty; setenv stdout usbtty" and
1676 attach your USB cable. The Unix command "dmesg" should print
1677 it has found a new device. The environment variable usbtty
1678 can be set to gserial or cdc_acm to enable your device to
1679 appear to a USB host as a Linux gserial device or a
1680 Common Device Class Abstract Control Model serial device.
1681 If you select usbtty = gserial you should be able to enumerate
1683 # modprobe usbserial vendor=0xVendorID product=0xProductID
1684 else if using cdc_acm, simply setting the environment
1685 variable usbtty to be cdc_acm should suffice. The following
1686 might be defined in YourBoardName.h
1689 Define this to build a UDC device
1692 Define this to have a tty type of device available to
1693 talk to the UDC device
1696 Define this to enable the high speed support for usb
1697 device and usbtty. If this feature is enabled, a routine
1698 int is_usbd_high_speed(void)
1699 also needs to be defined by the driver to dynamically poll
1700 whether the enumeration has succeded at high speed or full
1703 CONFIG_SYS_CONSOLE_IS_IN_ENV
1704 Define this if you want stdin, stdout &/or stderr to
1708 CONFIG_SYS_USB_EXTC_CLK 0xBLAH
1709 Derive USB clock from external clock "blah"
1710 - CONFIG_SYS_USB_EXTC_CLK 0x02
1712 CONFIG_SYS_USB_BRG_CLK 0xBLAH
1713 Derive USB clock from brgclk
1714 - CONFIG_SYS_USB_BRG_CLK 0x04
1716 If you have a USB-IF assigned VendorID then you may wish to
1717 define your own vendor specific values either in BoardName.h
1718 or directly in usbd_vendor_info.h. If you don't define
1719 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
1720 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
1721 should pretend to be a Linux device to it's target host.
1723 CONFIG_USBD_MANUFACTURER
1724 Define this string as the name of your company for
1725 - CONFIG_USBD_MANUFACTURER "my company"
1727 CONFIG_USBD_PRODUCT_NAME
1728 Define this string as the name of your product
1729 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
1731 CONFIG_USBD_VENDORID
1732 Define this as your assigned Vendor ID from the USB
1733 Implementors Forum. This *must* be a genuine Vendor ID
1734 to avoid polluting the USB namespace.
1735 - CONFIG_USBD_VENDORID 0xFFFF
1737 CONFIG_USBD_PRODUCTID
1738 Define this as the unique Product ID
1740 - CONFIG_USBD_PRODUCTID 0xFFFF
1742 - ULPI Layer Support:
1743 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via
1744 the generic ULPI layer. The generic layer accesses the ULPI PHY
1745 via the platform viewport, so you need both the genric layer and
1746 the viewport enabled. Currently only Chipidea/ARC based
1747 viewport is supported.
1748 To enable the ULPI layer support, define CONFIG_USB_ULPI and
1749 CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
1750 If your ULPI phy needs a different reference clock than the
1751 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to
1752 the appropriate value in Hz.
1755 The MMC controller on the Intel PXA is supported. To
1756 enable this define CONFIG_MMC. The MMC can be
1757 accessed from the boot prompt by mapping the device
1758 to physical memory similar to flash. Command line is
1759 enabled with CONFIG_CMD_MMC. The MMC driver also works with
1760 the FAT fs. This is enabled with CONFIG_CMD_FAT.
1763 Support for Renesas on-chip MMCIF controller
1765 CONFIG_SH_MMCIF_ADDR
1766 Define the base address of MMCIF registers
1769 Define the clock frequency for MMCIF
1772 Enable the generic MMC driver
1774 CONFIG_SUPPORT_EMMC_BOOT
1775 Enable some additional features of the eMMC boot partitions.
1777 CONFIG_SUPPORT_EMMC_RPMB
1778 Enable the commands for reading, writing and programming the
1779 key for the Replay Protection Memory Block partition in eMMC.
1781 - USB Device Firmware Update (DFU) class support:
1782 CONFIG_USB_FUNCTION_DFU
1783 This enables the USB portion of the DFU USB class
1786 This enables the command "dfu" which is used to have
1787 U-Boot create a DFU class device via USB. This command
1788 requires that the "dfu_alt_info" environment variable be
1789 set and define the alt settings to expose to the host.
1792 This enables support for exposing (e)MMC devices via DFU.
1795 This enables support for exposing NAND devices via DFU.
1798 This enables support for exposing RAM via DFU.
1799 Note: DFU spec refer to non-volatile memory usage, but
1800 allow usages beyond the scope of spec - here RAM usage,
1801 one that would help mostly the developer.
1803 CONFIG_SYS_DFU_DATA_BUF_SIZE
1804 Dfu transfer uses a buffer before writing data to the
1805 raw storage device. Make the size (in bytes) of this buffer
1806 configurable. The size of this buffer is also configurable
1807 through the "dfu_bufsiz" environment variable.
1809 CONFIG_SYS_DFU_MAX_FILE_SIZE
1810 When updating files rather than the raw storage device,
1811 we use a static buffer to copy the file into and then write
1812 the buffer once we've been given the whole file. Define
1813 this to the maximum filesize (in bytes) for the buffer.
1814 Default is 4 MiB if undefined.
1816 DFU_DEFAULT_POLL_TIMEOUT
1817 Poll timeout [ms], is the timeout a device can send to the
1818 host. The host must wait for this timeout before sending
1819 a subsequent DFU_GET_STATUS request to the device.
1821 DFU_MANIFEST_POLL_TIMEOUT
1822 Poll timeout [ms], which the device sends to the host when
1823 entering dfuMANIFEST state. Host waits this timeout, before
1824 sending again an USB request to the device.
1826 - USB Device Android Fastboot support:
1827 CONFIG_USB_FUNCTION_FASTBOOT
1828 This enables the USB part of the fastboot gadget
1831 This enables the command "fastboot" which enables the Android
1832 fastboot mode for the platform's USB device. Fastboot is a USB
1833 protocol for downloading images, flashing and device control
1834 used on Android devices.
1835 See doc/README.android-fastboot for more information.
1837 CONFIG_ANDROID_BOOT_IMAGE
1838 This enables support for booting images which use the Android
1839 image format header.
1841 CONFIG_FASTBOOT_BUF_ADDR
1842 The fastboot protocol requires a large memory buffer for
1843 downloads. Define this to the starting RAM address to use for
1846 CONFIG_FASTBOOT_BUF_SIZE
1847 The fastboot protocol requires a large memory buffer for
1848 downloads. This buffer should be as large as possible for a
1849 platform. Define this to the size available RAM for fastboot.
1851 CONFIG_FASTBOOT_FLASH
1852 The fastboot protocol includes a "flash" command for writing
1853 the downloaded image to a non-volatile storage device. Define
1854 this to enable the "fastboot flash" command.
1856 CONFIG_FASTBOOT_FLASH_MMC_DEV
1857 The fastboot "flash" command requires additional information
1858 regarding the non-volatile storage device. Define this to
1859 the eMMC device that fastboot should use to store the image.
1861 CONFIG_FASTBOOT_GPT_NAME
1862 The fastboot "flash" command supports writing the downloaded
1863 image to the Protective MBR and the Primary GUID Partition
1864 Table. (Additionally, this downloaded image is post-processed
1865 to generate and write the Backup GUID Partition Table.)
1866 This occurs when the specified "partition name" on the
1867 "fastboot flash" command line matches this value.
1868 Default is GPT_ENTRY_NAME (currently "gpt") if undefined.
1870 - Journaling Flash filesystem support:
1871 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
1872 CONFIG_JFFS2_NAND_DEV
1873 Define these for a default partition on a NAND device
1875 CONFIG_SYS_JFFS2_FIRST_SECTOR,
1876 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
1877 Define these for a default partition on a NOR device
1879 CONFIG_SYS_JFFS_CUSTOM_PART
1880 Define this to create an own partition. You have to provide a
1881 function struct part_info* jffs2_part_info(int part_num)
1883 If you define only one JFFS2 partition you may also want to
1884 #define CONFIG_SYS_JFFS_SINGLE_PART 1
1885 to disable the command chpart. This is the default when you
1886 have not defined a custom partition
1888 - FAT(File Allocation Table) filesystem write function support:
1891 Define this to enable support for saving memory data as a
1892 file in FAT formatted partition.
1894 This will also enable the command "fatwrite" enabling the
1895 user to write files to FAT.
1897 CBFS (Coreboot Filesystem) support
1900 Define this to enable support for reading from a Coreboot
1901 filesystem. Available commands are cbfsinit, cbfsinfo, cbfsls
1904 - FAT(File Allocation Table) filesystem cluster size:
1905 CONFIG_FS_FAT_MAX_CLUSTSIZE
1907 Define the max cluster size for fat operations else
1908 a default value of 65536 will be defined.
1913 Define this to enable standard (PC-Style) keyboard
1917 Standard PC keyboard driver with US (is default) and
1918 GERMAN key layout (switch via environment 'keymap=de') support.
1919 Export function i8042_kbd_init, i8042_tstc and i8042_getc
1920 for cfb_console. Supports cursor blinking.
1923 Enables a Chrome OS keyboard using the CROS_EC interface.
1924 This uses CROS_EC to communicate with a second microcontroller
1925 which provides key scans on request.
1930 Define this to enable video support (for output to
1933 CONFIG_VIDEO_CT69000
1935 Enable Chips & Technologies 69000 Video chip
1937 CONFIG_VIDEO_SMI_LYNXEM
1938 Enable Silicon Motion SMI 712/710/810 Video chip. The
1939 video output is selected via environment 'videoout'
1940 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
1943 For the CT69000 and SMI_LYNXEM drivers, videomode is
1944 selected via environment 'videomode'. Two different ways
1946 - "videomode=num" 'num' is a standard LiLo mode numbers.
1947 Following standard modes are supported (* is default):
1949 Colors 640x480 800x600 1024x768 1152x864 1280x1024
1950 -------------+---------------------------------------------
1951 8 bits | 0x301* 0x303 0x305 0x161 0x307
1952 15 bits | 0x310 0x313 0x316 0x162 0x319
1953 16 bits | 0x311 0x314 0x317 0x163 0x31A
1954 24 bits | 0x312 0x315 0x318 ? 0x31B
1955 -------------+---------------------------------------------
1956 (i.e. setenv videomode 317; saveenv; reset;)
1958 - "videomode=bootargs" all the video parameters are parsed
1959 from the bootargs. (See drivers/video/videomodes.c)
1962 CONFIG_VIDEO_SED13806
1963 Enable Epson SED13806 driver. This driver supports 8bpp
1964 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
1965 or CONFIG_VIDEO_SED13806_16BPP
1968 Enable the Freescale DIU video driver. Reference boards for
1969 SOCs that have a DIU should define this macro to enable DIU
1970 support, and should also define these other macros:
1976 CONFIG_VIDEO_SW_CURSOR
1977 CONFIG_VGA_AS_SINGLE_DEVICE
1979 CONFIG_VIDEO_BMP_LOGO
1981 The DIU driver will look for the 'video-mode' environment
1982 variable, and if defined, enable the DIU as a console during
1983 boot. See the documentation file README.video for a
1984 description of this variable.
1990 Define this to enable a custom keyboard support.
1991 This simply calls drv_keyboard_init() which must be
1992 defined in your board-specific files.
1993 The only board using this so far is RBC823.
1995 - LCD Support: CONFIG_LCD
1997 Define this to enable LCD support (for output to LCD
1998 display); also select one of the supported displays
1999 by defining one of these:
2003 HITACHI TX09D70VM1CCA, 3.5", 240x320.
2005 CONFIG_NEC_NL6448AC33:
2007 NEC NL6448AC33-18. Active, color, single scan.
2009 CONFIG_NEC_NL6448BC20
2011 NEC NL6448BC20-08. 6.5", 640x480.
2012 Active, color, single scan.
2014 CONFIG_NEC_NL6448BC33_54
2016 NEC NL6448BC33-54. 10.4", 640x480.
2017 Active, color, single scan.
2021 Sharp 320x240. Active, color, single scan.
2022 It isn't 16x9, and I am not sure what it is.
2024 CONFIG_SHARP_LQ64D341
2026 Sharp LQ64D341 display, 640x480.
2027 Active, color, single scan.
2031 HLD1045 display, 640x480.
2032 Active, color, single scan.
2036 Optrex CBL50840-2 NF-FW 99 22 M5
2038 Hitachi LMG6912RPFC-00T
2042 320x240. Black & white.
2044 Normally display is black on white background; define
2045 CONFIG_SYS_WHITE_ON_BLACK to get it inverted.
2047 CONFIG_LCD_ALIGNMENT
2049 Normally the LCD is page-aligned (typically 4KB). If this is
2050 defined then the LCD will be aligned to this value instead.
2051 For ARM it is sometimes useful to use MMU_SECTION_SIZE
2052 here, since it is cheaper to change data cache settings on
2053 a per-section basis.
2055 CONFIG_CONSOLE_SCROLL_LINES
2057 When the console need to be scrolled, this is the number of
2058 lines to scroll by. It defaults to 1. Increasing this makes
2059 the console jump but can help speed up operation when scrolling
2064 Sometimes, for example if the display is mounted in portrait
2065 mode or even if it's mounted landscape but rotated by 180degree,
2066 we need to rotate our content of the display relative to the
2067 framebuffer, so that user can read the messages which are
2069 Once CONFIG_LCD_ROTATION is defined, the lcd_console will be
2070 initialized with a given rotation from "vl_rot" out of
2071 "vidinfo_t" which is provided by the board specific code.
2072 The value for vl_rot is coded as following (matching to
2073 fbcon=rotate:<n> linux-kernel commandline):
2074 0 = no rotation respectively 0 degree
2075 1 = 90 degree rotation
2076 2 = 180 degree rotation
2077 3 = 270 degree rotation
2079 If CONFIG_LCD_ROTATION is not defined, the console will be
2080 initialized with 0degree rotation.
2084 Support drawing of RLE8-compressed bitmaps on the LCD.
2088 Enables an 'i2c edid' command which can read EDID
2089 information over I2C from an attached LCD display.
2091 - Splash Screen Support: CONFIG_SPLASH_SCREEN
2093 If this option is set, the environment is checked for
2094 a variable "splashimage". If found, the usual display
2095 of logo, copyright and system information on the LCD
2096 is suppressed and the BMP image at the address
2097 specified in "splashimage" is loaded instead. The
2098 console is redirected to the "nulldev", too. This
2099 allows for a "silent" boot where a splash screen is
2100 loaded very quickly after power-on.
2102 CONFIG_SPLASHIMAGE_GUARD
2104 If this option is set, then U-Boot will prevent the environment
2105 variable "splashimage" from being set to a problematic address
2106 (see README.displaying-bmps).
2107 This option is useful for targets where, due to alignment
2108 restrictions, an improperly aligned BMP image will cause a data
2109 abort. If you think you will not have problems with unaligned
2110 accesses (for example because your toolchain prevents them)
2111 there is no need to set this option.
2113 CONFIG_SPLASH_SCREEN_ALIGN
2115 If this option is set the splash image can be freely positioned
2116 on the screen. Environment variable "splashpos" specifies the
2117 position as "x,y". If a positive number is given it is used as
2118 number of pixel from left/top. If a negative number is given it
2119 is used as number of pixel from right/bottom. You can also
2120 specify 'm' for centering the image.
2123 setenv splashpos m,m
2124 => image at center of screen
2126 setenv splashpos 30,20
2127 => image at x = 30 and y = 20
2129 setenv splashpos -10,m
2130 => vertically centered image
2131 at x = dspWidth - bmpWidth - 9
2133 - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
2135 If this option is set, additionally to standard BMP
2136 images, gzipped BMP images can be displayed via the
2137 splashscreen support or the bmp command.
2139 - Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
2141 If this option is set, 8-bit RLE compressed BMP images
2142 can be displayed via the splashscreen support or the
2145 - Do compressing for memory range:
2148 If this option is set, it would use zlib deflate method
2149 to compress the specified memory at its best effort.
2151 - Compression support:
2154 Enabled by default to support gzip compressed images.
2158 If this option is set, support for bzip2 compressed
2159 images is included. If not, only uncompressed and gzip
2160 compressed images are supported.
2162 NOTE: the bzip2 algorithm requires a lot of RAM, so
2163 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
2168 If this option is set, support for lzma compressed
2171 Note: The LZMA algorithm adds between 2 and 4KB of code and it
2172 requires an amount of dynamic memory that is given by the
2175 (1846 + 768 << (lc + lp)) * sizeof(uint16)
2177 Where lc and lp stand for, respectively, Literal context bits
2178 and Literal pos bits.
2180 This value is upper-bounded by 14MB in the worst case. Anyway,
2181 for a ~4MB large kernel image, we have lc=3 and lp=0 for a
2182 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is
2183 a very small buffer.
2185 Use the lzmainfo tool to determinate the lc and lp values and
2186 then calculate the amount of needed dynamic memory (ensuring
2187 the appropriate CONFIG_SYS_MALLOC_LEN value).
2191 If this option is set, support for LZO compressed images
2197 The address of PHY on MII bus.
2199 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
2201 The clock frequency of the MII bus
2205 If this option is set, support for speed/duplex
2206 detection of gigabit PHY is included.
2208 CONFIG_PHY_RESET_DELAY
2210 Some PHY like Intel LXT971A need extra delay after
2211 reset before any MII register access is possible.
2212 For such PHY, set this option to the usec delay
2213 required. (minimum 300usec for LXT971A)
2215 CONFIG_PHY_CMD_DELAY (ppc4xx)
2217 Some PHY like Intel LXT971A need extra delay after
2218 command issued before MII status register can be read
2223 Define a default value for the IP address to use for
2224 the default Ethernet interface, in case this is not
2225 determined through e.g. bootp.
2226 (Environment variable "ipaddr")
2228 - Server IP address:
2231 Defines a default value for the IP address of a TFTP
2232 server to contact when using the "tftboot" command.
2233 (Environment variable "serverip")
2235 CONFIG_KEEP_SERVERADDR
2237 Keeps the server's MAC address, in the env 'serveraddr'
2238 for passing to bootargs (like Linux's netconsole option)
2240 - Gateway IP address:
2243 Defines a default value for the IP address of the
2244 default router where packets to other networks are
2246 (Environment variable "gatewayip")
2251 Defines a default value for the subnet mask (or
2252 routing prefix) which is used to determine if an IP
2253 address belongs to the local subnet or needs to be
2254 forwarded through a router.
2255 (Environment variable "netmask")
2257 - Multicast TFTP Mode:
2260 Defines whether you want to support multicast TFTP as per
2261 rfc-2090; for example to work with atftp. Lets lots of targets
2262 tftp down the same boot image concurrently. Note: the Ethernet
2263 driver in use must provide a function: mcast() to join/leave a
2266 - BOOTP Recovery Mode:
2267 CONFIG_BOOTP_RANDOM_DELAY
2269 If you have many targets in a network that try to
2270 boot using BOOTP, you may want to avoid that all
2271 systems send out BOOTP requests at precisely the same
2272 moment (which would happen for instance at recovery
2273 from a power failure, when all systems will try to
2274 boot, thus flooding the BOOTP server. Defining
2275 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
2276 inserted before sending out BOOTP requests. The
2277 following delays are inserted then:
2279 1st BOOTP request: delay 0 ... 1 sec
2280 2nd BOOTP request: delay 0 ... 2 sec
2281 3rd BOOTP request: delay 0 ... 4 sec
2283 BOOTP requests: delay 0 ... 8 sec
2285 CONFIG_BOOTP_ID_CACHE_SIZE
2287 BOOTP packets are uniquely identified using a 32-bit ID. The
2288 server will copy the ID from client requests to responses and
2289 U-Boot will use this to determine if it is the destination of
2290 an incoming response. Some servers will check that addresses
2291 aren't in use before handing them out (usually using an ARP
2292 ping) and therefore take up to a few hundred milliseconds to
2293 respond. Network congestion may also influence the time it
2294 takes for a response to make it back to the client. If that
2295 time is too long, U-Boot will retransmit requests. In order
2296 to allow earlier responses to still be accepted after these
2297 retransmissions, U-Boot's BOOTP client keeps a small cache of
2298 IDs. The CONFIG_BOOTP_ID_CACHE_SIZE controls the size of this
2299 cache. The default is to keep IDs for up to four outstanding
2300 requests. Increasing this will allow U-Boot to accept offers
2301 from a BOOTP client in networks with unusually high latency.
2303 - BOOTP Random transaction ID:
2304 CONFIG_BOOTP_RANDOM_ID
2306 The standard algorithm to generate a DHCP/BOOTP transaction ID
2307 by using the MAC address and the current time stamp may not
2308 quite unlikely produce duplicate transaction IDs from different
2309 clients in the same network. This option creates a transaction
2310 ID using the rand() function. Provided that the RNG has been
2311 seeded well, this should guarantee unique transaction IDs
2314 - DHCP Advanced Options:
2315 You can fine tune the DHCP functionality by defining
2316 CONFIG_BOOTP_* symbols:
2318 CONFIG_BOOTP_SUBNETMASK
2319 CONFIG_BOOTP_GATEWAY
2320 CONFIG_BOOTP_HOSTNAME
2321 CONFIG_BOOTP_NISDOMAIN
2322 CONFIG_BOOTP_BOOTPATH
2323 CONFIG_BOOTP_BOOTFILESIZE
2326 CONFIG_BOOTP_SEND_HOSTNAME
2327 CONFIG_BOOTP_NTPSERVER
2328 CONFIG_BOOTP_TIMEOFFSET
2329 CONFIG_BOOTP_VENDOREX
2330 CONFIG_BOOTP_MAY_FAIL
2332 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
2333 environment variable, not the BOOTP server.
2335 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found
2336 after the configured retry count, the call will fail
2337 instead of starting over. This can be used to fail over
2338 to Link-local IP address configuration if the DHCP server
2341 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
2342 serverip from a DHCP server, it is possible that more
2343 than one DNS serverip is offered to the client.
2344 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
2345 serverip will be stored in the additional environment
2346 variable "dnsip2". The first DNS serverip is always
2347 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
2350 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
2351 to do a dynamic update of a DNS server. To do this, they
2352 need the hostname of the DHCP requester.
2353 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
2354 of the "hostname" environment variable is passed as
2355 option 12 to the DHCP server.
2357 CONFIG_BOOTP_DHCP_REQUEST_DELAY
2359 A 32bit value in microseconds for a delay between
2360 receiving a "DHCP Offer" and sending the "DHCP Request".
2361 This fixes a problem with certain DHCP servers that don't
2362 respond 100% of the time to a "DHCP request". E.g. On an
2363 AT91RM9200 processor running at 180MHz, this delay needed
2364 to be *at least* 15,000 usec before a Windows Server 2003
2365 DHCP server would reply 100% of the time. I recommend at
2366 least 50,000 usec to be safe. The alternative is to hope
2367 that one of the retries will be successful but note that
2368 the DHCP timeout and retry process takes a longer than
2371 - Link-local IP address negotiation:
2372 Negotiate with other link-local clients on the local network
2373 for an address that doesn't require explicit configuration.
2374 This is especially useful if a DHCP server cannot be guaranteed
2375 to exist in all environments that the device must operate.
2377 See doc/README.link-local for more information.
2380 CONFIG_CDP_DEVICE_ID
2382 The device id used in CDP trigger frames.
2384 CONFIG_CDP_DEVICE_ID_PREFIX
2386 A two character string which is prefixed to the MAC address
2391 A printf format string which contains the ascii name of
2392 the port. Normally is set to "eth%d" which sets
2393 eth0 for the first Ethernet, eth1 for the second etc.
2395 CONFIG_CDP_CAPABILITIES
2397 A 32bit integer which indicates the device capabilities;
2398 0x00000010 for a normal host which does not forwards.
2402 An ascii string containing the version of the software.
2406 An ascii string containing the name of the platform.
2410 A 32bit integer sent on the trigger.
2412 CONFIG_CDP_POWER_CONSUMPTION
2414 A 16bit integer containing the power consumption of the
2415 device in .1 of milliwatts.
2417 CONFIG_CDP_APPLIANCE_VLAN_TYPE
2419 A byte containing the id of the VLAN.
2421 - Status LED: CONFIG_STATUS_LED
2423 Several configurations allow to display the current
2424 status using a LED. For instance, the LED will blink
2425 fast while running U-Boot code, stop blinking as
2426 soon as a reply to a BOOTP request was received, and
2427 start blinking slow once the Linux kernel is running
2428 (supported by a status LED driver in the Linux
2429 kernel). Defining CONFIG_STATUS_LED enables this
2435 The status LED can be connected to a GPIO pin.
2436 In such cases, the gpio_led driver can be used as a
2437 status LED backend implementation. Define CONFIG_GPIO_LED
2438 to include the gpio_led driver in the U-Boot binary.
2440 CONFIG_GPIO_LED_INVERTED_TABLE
2441 Some GPIO connected LEDs may have inverted polarity in which
2442 case the GPIO high value corresponds to LED off state and
2443 GPIO low value corresponds to LED on state.
2444 In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined
2445 with a list of GPIO LEDs that have inverted polarity.
2447 - CAN Support: CONFIG_CAN_DRIVER
2449 Defining CONFIG_CAN_DRIVER enables CAN driver support
2450 on those systems that support this (optional)
2451 feature, like the TQM8xxL modules.
2453 - I2C Support: CONFIG_SYS_I2C
2455 This enable the NEW i2c subsystem, and will allow you to use
2456 i2c commands at the u-boot command line (as long as you set
2457 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c
2458 based realtime clock chips or other i2c devices. See
2459 common/cmd_i2c.c for a description of the command line
2462 ported i2c driver to the new framework:
2463 - drivers/i2c/soft_i2c.c:
2464 - activate first bus with CONFIG_SYS_I2C_SOFT define
2465 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE
2466 for defining speed and slave address
2467 - activate second bus with I2C_SOFT_DECLARATIONS2 define
2468 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2
2469 for defining speed and slave address
2470 - activate third bus with I2C_SOFT_DECLARATIONS3 define
2471 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3
2472 for defining speed and slave address
2473 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define
2474 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4
2475 for defining speed and slave address
2477 - drivers/i2c/fsl_i2c.c:
2478 - activate i2c driver with CONFIG_SYS_I2C_FSL
2479 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register
2480 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and
2481 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first
2483 - If your board supports a second fsl i2c bus, define
2484 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset
2485 CONFIG_SYS_FSL_I2C2_SPEED for the speed and
2486 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the
2489 - drivers/i2c/tegra_i2c.c:
2490 - activate this driver with CONFIG_SYS_I2C_TEGRA
2491 - This driver adds 4 i2c buses with a fix speed from
2492 100000 and the slave addr 0!
2494 - drivers/i2c/ppc4xx_i2c.c
2495 - activate this driver with CONFIG_SYS_I2C_PPC4XX
2496 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0
2497 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1
2499 - drivers/i2c/i2c_mxc.c
2500 - activate this driver with CONFIG_SYS_I2C_MXC
2501 - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED
2502 - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE
2503 - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED
2504 - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE
2505 - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED
2506 - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE
2507 If those defines are not set, default value is 100000
2508 for speed, and 0 for slave.
2509 - enable bus 3 with CONFIG_SYS_I2C_MXC_I2C3
2510 - enable bus 4 with CONFIG_SYS_I2C_MXC_I2C4
2512 - drivers/i2c/rcar_i2c.c:
2513 - activate this driver with CONFIG_SYS_I2C_RCAR
2514 - This driver adds 4 i2c buses
2516 - CONFIG_SYS_RCAR_I2C0_BASE for setting the register channel 0
2517 - CONFIG_SYS_RCAR_I2C0_SPEED for for the speed channel 0
2518 - CONFIG_SYS_RCAR_I2C1_BASE for setting the register channel 1
2519 - CONFIG_SYS_RCAR_I2C1_SPEED for for the speed channel 1
2520 - CONFIG_SYS_RCAR_I2C2_BASE for setting the register channel 2
2521 - CONFIG_SYS_RCAR_I2C2_SPEED for for the speed channel 2
2522 - CONFIG_SYS_RCAR_I2C3_BASE for setting the register channel 3
2523 - CONFIG_SYS_RCAR_I2C3_SPEED for for the speed channel 3
2524 - CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS for number of i2c buses
2526 - drivers/i2c/sh_i2c.c:
2527 - activate this driver with CONFIG_SYS_I2C_SH
2528 - This driver adds from 2 to 5 i2c buses
2530 - CONFIG_SYS_I2C_SH_BASE0 for setting the register channel 0
2531 - CONFIG_SYS_I2C_SH_SPEED0 for for the speed channel 0
2532 - CONFIG_SYS_I2C_SH_BASE1 for setting the register channel 1
2533 - CONFIG_SYS_I2C_SH_SPEED1 for for the speed channel 1
2534 - CONFIG_SYS_I2C_SH_BASE2 for setting the register channel 2
2535 - CONFIG_SYS_I2C_SH_SPEED2 for for the speed channel 2
2536 - CONFIG_SYS_I2C_SH_BASE3 for setting the register channel 3
2537 - CONFIG_SYS_I2C_SH_SPEED3 for for the speed channel 3
2538 - CONFIG_SYS_I2C_SH_BASE4 for setting the register channel 4
2539 - CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4
2540 - CONFIG_SYS_I2C_SH_BASE5 for setting the register channel 5
2541 - CONFIG_SYS_I2C_SH_SPEED5 for for the speed channel 5
2542 - CONFIG_SYS_I2C_SH_NUM_CONTROLLERS for number of i2c buses
2544 - drivers/i2c/omap24xx_i2c.c
2545 - activate this driver with CONFIG_SYS_I2C_OMAP24XX
2546 - CONFIG_SYS_OMAP24_I2C_SPEED speed channel 0
2547 - CONFIG_SYS_OMAP24_I2C_SLAVE slave addr channel 0
2548 - CONFIG_SYS_OMAP24_I2C_SPEED1 speed channel 1
2549 - CONFIG_SYS_OMAP24_I2C_SLAVE1 slave addr channel 1
2550 - CONFIG_SYS_OMAP24_I2C_SPEED2 speed channel 2
2551 - CONFIG_SYS_OMAP24_I2C_SLAVE2 slave addr channel 2
2552 - CONFIG_SYS_OMAP24_I2C_SPEED3 speed channel 3
2553 - CONFIG_SYS_OMAP24_I2C_SLAVE3 slave addr channel 3
2554 - CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4
2555 - CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4
2557 - drivers/i2c/zynq_i2c.c
2558 - activate this driver with CONFIG_SYS_I2C_ZYNQ
2559 - set CONFIG_SYS_I2C_ZYNQ_SPEED for speed setting
2560 - set CONFIG_SYS_I2C_ZYNQ_SLAVE for slave addr
2562 - drivers/i2c/s3c24x0_i2c.c:
2563 - activate this driver with CONFIG_SYS_I2C_S3C24X0
2564 - This driver adds i2c buses (11 for Exynos5250, Exynos5420
2565 9 i2c buses for Exynos4 and 1 for S3C24X0 SoCs from Samsung)
2566 with a fix speed from 100000 and the slave addr 0!
2568 - drivers/i2c/ihs_i2c.c
2569 - activate this driver with CONFIG_SYS_I2C_IHS
2570 - CONFIG_SYS_I2C_IHS_CH0 activate hardware channel 0
2571 - CONFIG_SYS_I2C_IHS_SPEED_0 speed channel 0
2572 - CONFIG_SYS_I2C_IHS_SLAVE_0 slave addr channel 0
2573 - CONFIG_SYS_I2C_IHS_CH1 activate hardware channel 1
2574 - CONFIG_SYS_I2C_IHS_SPEED_1 speed channel 1
2575 - CONFIG_SYS_I2C_IHS_SLAVE_1 slave addr channel 1
2576 - CONFIG_SYS_I2C_IHS_CH2 activate hardware channel 2
2577 - CONFIG_SYS_I2C_IHS_SPEED_2 speed channel 2
2578 - CONFIG_SYS_I2C_IHS_SLAVE_2 slave addr channel 2
2579 - CONFIG_SYS_I2C_IHS_CH3 activate hardware channel 3
2580 - CONFIG_SYS_I2C_IHS_SPEED_3 speed channel 3
2581 - CONFIG_SYS_I2C_IHS_SLAVE_3 slave addr channel 3
2585 CONFIG_SYS_NUM_I2C_BUSES
2586 Hold the number of i2c buses you want to use. If you
2587 don't use/have i2c muxes on your i2c bus, this
2588 is equal to CONFIG_SYS_NUM_I2C_ADAPTERS, and you can
2591 CONFIG_SYS_I2C_DIRECT_BUS
2592 define this, if you don't use i2c muxes on your hardware.
2593 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can
2596 CONFIG_SYS_I2C_MAX_HOPS
2597 define how many muxes are maximal consecutively connected
2598 on one i2c bus. If you not use i2c muxes, omit this
2601 CONFIG_SYS_I2C_BUSES
2602 hold a list of buses you want to use, only used if
2603 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example
2604 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and
2605 CONFIG_SYS_NUM_I2C_BUSES = 9:
2607 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \
2608 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \
2609 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \
2610 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \
2611 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \
2612 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \
2613 {1, {I2C_NULL_HOP}}, \
2614 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \
2615 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \
2619 bus 0 on adapter 0 without a mux
2620 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1
2621 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2
2622 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3
2623 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4
2624 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5
2625 bus 6 on adapter 1 without a mux
2626 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1
2627 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2
2629 If you do not have i2c muxes on your board, omit this define.
2631 - Legacy I2C Support: CONFIG_HARD_I2C
2633 NOTE: It is intended to move drivers to CONFIG_SYS_I2C which
2634 provides the following compelling advantages:
2636 - more than one i2c adapter is usable
2637 - approved multibus support
2638 - better i2c mux support
2640 ** Please consider updating your I2C driver now. **
2642 These enable legacy I2C serial bus commands. Defining
2643 CONFIG_HARD_I2C will include the appropriate I2C driver
2644 for the selected CPU.
2646 This will allow you to use i2c commands at the u-boot
2647 command line (as long as you set CONFIG_CMD_I2C in
2648 CONFIG_COMMANDS) and communicate with i2c based realtime
2649 clock chips. See common/cmd_i2c.c for a description of the
2650 command line interface.
2652 CONFIG_HARD_I2C selects a hardware I2C controller.
2654 There are several other quantities that must also be
2655 defined when you define CONFIG_HARD_I2C.
2657 In both cases you will need to define CONFIG_SYS_I2C_SPEED
2658 to be the frequency (in Hz) at which you wish your i2c bus
2659 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie
2660 the CPU's i2c node address).
2662 Now, the u-boot i2c code for the mpc8xx
2663 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node
2664 and so its address should therefore be cleared to 0 (See,
2665 eg, MPC823e User's Manual p.16-473). So, set
2666 CONFIG_SYS_I2C_SLAVE to 0.
2668 CONFIG_SYS_I2C_INIT_MPC5XXX
2670 When a board is reset during an i2c bus transfer
2671 chips might think that the current transfer is still
2672 in progress. Reset the slave devices by sending start
2673 commands until the slave device responds.
2675 That's all that's required for CONFIG_HARD_I2C.
2677 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT)
2678 then the following macros need to be defined (examples are
2679 from include/configs/lwmon.h):
2683 (Optional). Any commands necessary to enable the I2C
2684 controller or configure ports.
2686 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
2690 (Only for MPC8260 CPU). The I/O port to use (the code
2691 assumes both bits are on the same port). Valid values
2692 are 0..3 for ports A..D.
2696 The code necessary to make the I2C data line active
2697 (driven). If the data line is open collector, this
2700 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
2704 The code necessary to make the I2C data line tri-stated
2705 (inactive). If the data line is open collector, this
2708 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
2712 Code that returns true if the I2C data line is high,
2715 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
2719 If <bit> is true, sets the I2C data line high. If it
2720 is false, it clears it (low).
2722 eg: #define I2C_SDA(bit) \
2723 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
2724 else immr->im_cpm.cp_pbdat &= ~PB_SDA
2728 If <bit> is true, sets the I2C clock line high. If it
2729 is false, it clears it (low).
2731 eg: #define I2C_SCL(bit) \
2732 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
2733 else immr->im_cpm.cp_pbdat &= ~PB_SCL
2737 This delay is invoked four times per clock cycle so this
2738 controls the rate of data transfer. The data rate thus
2739 is 1 / (I2C_DELAY * 4). Often defined to be something
2742 #define I2C_DELAY udelay(2)
2744 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
2746 If your arch supports the generic GPIO framework (asm/gpio.h),
2747 then you may alternatively define the two GPIOs that are to be
2748 used as SCL / SDA. Any of the previous I2C_xxx macros will
2749 have GPIO-based defaults assigned to them as appropriate.
2751 You should define these to the GPIO value as given directly to
2752 the generic GPIO functions.
2754 CONFIG_SYS_I2C_INIT_BOARD
2756 When a board is reset during an i2c bus transfer
2757 chips might think that the current transfer is still
2758 in progress. On some boards it is possible to access
2759 the i2c SCLK line directly, either by using the
2760 processor pin as a GPIO or by having a second pin
2761 connected to the bus. If this option is defined a
2762 custom i2c_init_board() routine in boards/xxx/board.c
2763 is run early in the boot sequence.
2765 CONFIG_SYS_I2C_BOARD_LATE_INIT
2767 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is
2768 defined a custom i2c_board_late_init() routine in
2769 boards/xxx/board.c is run AFTER the operations in i2c_init()
2770 is completed. This callpoint can be used to unreset i2c bus
2771 using CPU i2c controller register accesses for CPUs whose i2c
2772 controller provide such a method. It is called at the end of
2773 i2c_init() to allow i2c_init operations to setup the i2c bus
2774 controller on the CPU (e.g. setting bus speed & slave address).
2776 CONFIG_I2CFAST (PPC405GP|PPC405EP only)
2778 This option enables configuration of bi_iic_fast[] flags
2779 in u-boot bd_info structure based on u-boot environment
2780 variable "i2cfast". (see also i2cfast)
2782 CONFIG_I2C_MULTI_BUS
2784 This option allows the use of multiple I2C buses, each of which
2785 must have a controller. At any point in time, only one bus is
2786 active. To switch to a different bus, use the 'i2c dev' command.
2787 Note that bus numbering is zero-based.
2789 CONFIG_SYS_I2C_NOPROBES
2791 This option specifies a list of I2C devices that will be skipped
2792 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
2793 is set, specify a list of bus-device pairs. Otherwise, specify
2794 a 1D array of device addresses
2797 #undef CONFIG_I2C_MULTI_BUS
2798 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
2800 will skip addresses 0x50 and 0x68 on a board with one I2C bus
2802 #define CONFIG_I2C_MULTI_BUS
2803 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
2805 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
2807 CONFIG_SYS_SPD_BUS_NUM
2809 If defined, then this indicates the I2C bus number for DDR SPD.
2810 If not defined, then U-Boot assumes that SPD is on I2C bus 0.
2812 CONFIG_SYS_RTC_BUS_NUM
2814 If defined, then this indicates the I2C bus number for the RTC.
2815 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
2817 CONFIG_SYS_DTT_BUS_NUM
2819 If defined, then this indicates the I2C bus number for the DTT.
2820 If not defined, then U-Boot assumes that DTT is on I2C bus 0.
2822 CONFIG_SYS_I2C_DTT_ADDR:
2824 If defined, specifies the I2C address of the DTT device.
2825 If not defined, then U-Boot uses predefined value for
2826 specified DTT device.
2828 CONFIG_SOFT_I2C_READ_REPEATED_START
2830 defining this will force the i2c_read() function in
2831 the soft_i2c driver to perform an I2C repeated start
2832 between writing the address pointer and reading the
2833 data. If this define is omitted the default behaviour
2834 of doing a stop-start sequence will be used. Most I2C
2835 devices can use either method, but some require one or
2838 - SPI Support: CONFIG_SPI
2840 Enables SPI driver (so far only tested with
2841 SPI EEPROM, also an instance works with Crystal A/D and
2842 D/As on the SACSng board)
2846 Enables the driver for SPI controller on SuperH. Currently
2847 only SH7757 is supported.
2851 Enables extended (16-bit) SPI EEPROM addressing.
2852 (symmetrical to CONFIG_I2C_X)
2856 Enables a software (bit-bang) SPI driver rather than
2857 using hardware support. This is a general purpose
2858 driver that only requires three general I/O port pins
2859 (two outputs, one input) to function. If this is
2860 defined, the board configuration must define several
2861 SPI configuration items (port pins to use, etc). For
2862 an example, see include/configs/sacsng.h.
2866 Enables a hardware SPI driver for general-purpose reads
2867 and writes. As with CONFIG_SOFT_SPI, the board configuration
2868 must define a list of chip-select function pointers.
2869 Currently supported on some MPC8xxx processors. For an
2870 example, see include/configs/mpc8349emds.h.
2874 Enables the driver for the SPI controllers on i.MX and MXC
2875 SoCs. Currently i.MX31/35/51 are supported.
2877 CONFIG_SYS_SPI_MXC_WAIT
2878 Timeout for waiting until spi transfer completed.
2879 default: (CONFIG_SYS_HZ/100) /* 10 ms */
2881 - FPGA Support: CONFIG_FPGA
2883 Enables FPGA subsystem.
2885 CONFIG_FPGA_<vendor>
2887 Enables support for specific chip vendors.
2890 CONFIG_FPGA_<family>
2892 Enables support for FPGA family.
2893 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
2897 Specify the number of FPGA devices to support.
2899 CONFIG_CMD_FPGA_LOADMK
2901 Enable support for fpga loadmk command
2903 CONFIG_CMD_FPGA_LOADP
2905 Enable support for fpga loadp command - load partial bitstream
2907 CONFIG_CMD_FPGA_LOADBP
2909 Enable support for fpga loadbp command - load partial bitstream
2912 CONFIG_SYS_FPGA_PROG_FEEDBACK
2914 Enable printing of hash marks during FPGA configuration.
2916 CONFIG_SYS_FPGA_CHECK_BUSY
2918 Enable checks on FPGA configuration interface busy
2919 status by the configuration function. This option
2920 will require a board or device specific function to
2925 If defined, a function that provides delays in the FPGA
2926 configuration driver.
2928 CONFIG_SYS_FPGA_CHECK_CTRLC
2929 Allow Control-C to interrupt FPGA configuration
2931 CONFIG_SYS_FPGA_CHECK_ERROR
2933 Check for configuration errors during FPGA bitfile
2934 loading. For example, abort during Virtex II
2935 configuration if the INIT_B line goes low (which
2936 indicated a CRC error).
2938 CONFIG_SYS_FPGA_WAIT_INIT
2940 Maximum time to wait for the INIT_B line to de-assert
2941 after PROB_B has been de-asserted during a Virtex II
2942 FPGA configuration sequence. The default time is 500
2945 CONFIG_SYS_FPGA_WAIT_BUSY
2947 Maximum time to wait for BUSY to de-assert during
2948 Virtex II FPGA configuration. The default is 5 ms.
2950 CONFIG_SYS_FPGA_WAIT_CONFIG
2952 Time to wait after FPGA configuration. The default is
2955 - Configuration Management:
2958 Some SoCs need special image types (e.g. U-Boot binary
2959 with a special header) as build targets. By defining
2960 CONFIG_BUILD_TARGET in the SoC / board header, this
2961 special image will be automatically built upon calling
2966 If defined, this string will be added to the U-Boot
2967 version information (U_BOOT_VERSION)
2969 - Vendor Parameter Protection:
2971 U-Boot considers the values of the environment
2972 variables "serial#" (Board Serial Number) and
2973 "ethaddr" (Ethernet Address) to be parameters that
2974 are set once by the board vendor / manufacturer, and
2975 protects these variables from casual modification by
2976 the user. Once set, these variables are read-only,
2977 and write or delete attempts are rejected. You can
2978 change this behaviour:
2980 If CONFIG_ENV_OVERWRITE is #defined in your config
2981 file, the write protection for vendor parameters is
2982 completely disabled. Anybody can change or delete
2985 Alternatively, if you define _both_ an ethaddr in the
2986 default env _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
2987 Ethernet address is installed in the environment,
2988 which can be changed exactly ONCE by the user. [The
2989 serial# is unaffected by this, i. e. it remains
2992 The same can be accomplished in a more flexible way
2993 for any variable by configuring the type of access
2994 to allow for those variables in the ".flags" variable
2995 or define CONFIG_ENV_FLAGS_LIST_STATIC.
3000 Define this variable to enable the reservation of
3001 "protected RAM", i. e. RAM which is not overwritten
3002 by U-Boot. Define CONFIG_PRAM to hold the number of
3003 kB you want to reserve for pRAM. You can overwrite
3004 this default value by defining an environment
3005 variable "pram" to the number of kB you want to
3006 reserve. Note that the board info structure will
3007 still show the full amount of RAM. If pRAM is
3008 reserved, a new environment variable "mem" will
3009 automatically be defined to hold the amount of
3010 remaining RAM in a form that can be passed as boot
3011 argument to Linux, for instance like that:
3013 setenv bootargs ... mem=\${mem}
3016 This way you can tell Linux not to use this memory,
3017 either, which results in a memory region that will
3018 not be affected by reboots.
3020 *WARNING* If your board configuration uses automatic
3021 detection of the RAM size, you must make sure that
3022 this memory test is non-destructive. So far, the
3023 following board configurations are known to be
3026 IVMS8, IVML24, SPD8xx, TQM8xxL,
3027 HERMES, IP860, RPXlite, LWMON,
3030 - Access to physical memory region (> 4GB)
3031 Some basic support is provided for operations on memory not
3032 normally accessible to U-Boot - e.g. some architectures
3033 support access to more than 4GB of memory on 32-bit
3034 machines using physical address extension or similar.
3035 Define CONFIG_PHYSMEM to access this basic support, which
3036 currently only supports clearing the memory.
3041 Define this variable to stop the system in case of a
3042 fatal error, so that you have to reset it manually.
3043 This is probably NOT a good idea for an embedded
3044 system where you want the system to reboot
3045 automatically as fast as possible, but it may be
3046 useful during development since you can try to debug
3047 the conditions that lead to the situation.
3049 CONFIG_NET_RETRY_COUNT
3051 This variable defines the number of retries for
3052 network operations like ARP, RARP, TFTP, or BOOTP
3053 before giving up the operation. If not defined, a
3054 default value of 5 is used.
3058 Timeout waiting for an ARP reply in milliseconds.
3062 Timeout in milliseconds used in NFS protocol.
3063 If you encounter "ERROR: Cannot umount" in nfs command,
3064 try longer timeout such as
3065 #define CONFIG_NFS_TIMEOUT 10000UL
3067 - Command Interpreter:
3068 CONFIG_AUTO_COMPLETE
3070 Enable auto completion of commands using TAB.
3072 CONFIG_SYS_PROMPT_HUSH_PS2
3074 This defines the secondary prompt string, which is
3075 printed when the command interpreter needs more input
3076 to complete a command. Usually "> ".
3080 In the current implementation, the local variables
3081 space and global environment variables space are
3082 separated. Local variables are those you define by
3083 simply typing `name=value'. To access a local
3084 variable later on, you have write `$name' or
3085 `${name}'; to execute the contents of a variable
3086 directly type `$name' at the command prompt.
3088 Global environment variables are those you use
3089 setenv/printenv to work with. To run a command stored
3090 in such a variable, you need to use the run command,
3091 and you must not use the '$' sign to access them.
3093 To store commands and special characters in a
3094 variable, please use double quotation marks
3095 surrounding the whole text of the variable, instead
3096 of the backslashes before semicolons and special
3099 - Command Line Editing and History:
3100 CONFIG_CMDLINE_EDITING
3102 Enable editing and History functions for interactive
3103 command line input operations
3105 - Default Environment:
3106 CONFIG_EXTRA_ENV_SETTINGS
3108 Define this to contain any number of null terminated
3109 strings (variable = value pairs) that will be part of
3110 the default environment compiled into the boot image.
3112 For example, place something like this in your
3113 board's config file:
3115 #define CONFIG_EXTRA_ENV_SETTINGS \
3119 Warning: This method is based on knowledge about the
3120 internal format how the environment is stored by the
3121 U-Boot code. This is NOT an official, exported
3122 interface! Although it is unlikely that this format
3123 will change soon, there is no guarantee either.
3124 You better know what you are doing here.
3126 Note: overly (ab)use of the default environment is
3127 discouraged. Make sure to check other ways to preset
3128 the environment like the "source" command or the
3131 CONFIG_ENV_VARS_UBOOT_CONFIG
3133 Define this in order to add variables describing the
3134 U-Boot build configuration to the default environment.
3135 These will be named arch, cpu, board, vendor, and soc.
3137 Enabling this option will cause the following to be defined:
3145 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG
3147 Define this in order to add variables describing certain
3148 run-time determined information about the hardware to the
3149 environment. These will be named board_name, board_rev.
3151 CONFIG_DELAY_ENVIRONMENT
3153 Normally the environment is loaded when the board is
3154 initialised so that it is available to U-Boot. This inhibits
3155 that so that the environment is not available until
3156 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL
3157 this is instead controlled by the value of
3158 /config/load-environment.
3160 - Parallel Flash support:
3163 Traditionally U-boot was run on systems with parallel NOR
3164 flash. This option is used to disable support for parallel NOR
3165 flash. This option should be defined if the board does not have
3168 If this option is not defined one of the generic flash drivers
3169 (e.g. CONFIG_FLASH_CFI_DRIVER or CONFIG_ST_SMI) must be
3170 selected or the board must provide an implementation of the
3171 flash API (see include/flash.h).
3173 - DataFlash Support:
3174 CONFIG_HAS_DATAFLASH
3176 Defining this option enables DataFlash features and
3177 allows to read/write in Dataflash via the standard
3180 - Serial Flash support
3183 Defining this option enables SPI flash commands
3184 'sf probe/read/write/erase/update'.
3186 Usage requires an initial 'probe' to define the serial
3187 flash parameters, followed by read/write/erase/update
3190 The following defaults may be provided by the platform
3191 to handle the common case when only a single serial
3192 flash is present on the system.
3194 CONFIG_SF_DEFAULT_BUS Bus identifier
3195 CONFIG_SF_DEFAULT_CS Chip-select
3196 CONFIG_SF_DEFAULT_MODE (see include/spi.h)
3197 CONFIG_SF_DEFAULT_SPEED in Hz
3201 Define this option to include a destructive SPI flash
3204 CONFIG_SF_DUAL_FLASH Dual flash memories
3206 Define this option to use dual flash support where two flash
3207 memories can be connected with a given cs line.
3208 Currently Xilinx Zynq qspi supports these type of connections.
3210 - SystemACE Support:
3213 Adding this option adds support for Xilinx SystemACE
3214 chips attached via some sort of local bus. The address
3215 of the chip must also be defined in the
3216 CONFIG_SYS_SYSTEMACE_BASE macro. For example:
3218 #define CONFIG_SYSTEMACE
3219 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000
3221 When SystemACE support is added, the "ace" device type
3222 becomes available to the fat commands, i.e. fatls.
3224 - TFTP Fixed UDP Port:
3227 If this is defined, the environment variable tftpsrcp
3228 is used to supply the TFTP UDP source port value.
3229 If tftpsrcp isn't defined, the normal pseudo-random port
3230 number generator is used.
3232 Also, the environment variable tftpdstp is used to supply
3233 the TFTP UDP destination port value. If tftpdstp isn't
3234 defined, the normal port 69 is used.
3236 The purpose for tftpsrcp is to allow a TFTP server to
3237 blindly start the TFTP transfer using the pre-configured
3238 target IP address and UDP port. This has the effect of
3239 "punching through" the (Windows XP) firewall, allowing
3240 the remainder of the TFTP transfer to proceed normally.
3241 A better solution is to properly configure the firewall,
3242 but sometimes that is not allowed.
3247 This enables a generic 'hash' command which can produce
3248 hashes / digests from a few algorithms (e.g. SHA1, SHA256).
3252 Enable the hash verify command (hash -v). This adds to code
3255 CONFIG_SHA1 - This option enables support of hashing using SHA1
3256 algorithm. The hash is calculated in software.
3257 CONFIG_SHA256 - This option enables support of hashing using
3258 SHA256 algorithm. The hash is calculated in software.
3259 CONFIG_SHA_HW_ACCEL - This option enables hardware acceleration
3260 for SHA1/SHA256 hashing.
3261 This affects the 'hash' command and also the
3262 hash_lookup_algo() function.
3263 CONFIG_SHA_PROG_HW_ACCEL - This option enables
3264 hardware-acceleration for SHA1/SHA256 progressive hashing.
3265 Data can be streamed in a block at a time and the hashing
3266 is performed in hardware.
3268 Note: There is also a sha1sum command, which should perhaps
3269 be deprecated in favour of 'hash sha1'.
3271 - Freescale i.MX specific commands:
3272 CONFIG_CMD_HDMIDETECT
3273 This enables 'hdmidet' command which returns true if an
3274 HDMI monitor is detected. This command is i.MX 6 specific.
3277 This enables the 'bmode' (bootmode) command for forcing
3278 a boot from specific media.
3280 This is useful for forcing the ROM's usb downloader to
3281 activate upon a watchdog reset which is nice when iterating
3282 on U-Boot. Using the reset button or running bmode normal
3283 will set it back to normal. This command currently
3284 supports i.MX53 and i.MX6.
3289 This enables the RSA algorithm used for FIT image verification
3290 in U-Boot. See doc/uImage.FIT/signature.txt for more information.
3292 The Modular Exponentiation algorithm in RSA is implemented using
3293 driver model. So CONFIG_DM needs to be enabled by default for this
3294 library to function.
3296 The signing part is build into mkimage regardless of this
3297 option. The software based modular exponentiation is built into
3298 mkimage irrespective of this option.
3300 - bootcount support:
3301 CONFIG_BOOTCOUNT_LIMIT
3303 This enables the bootcounter support, see:
3304 http://www.denx.de/wiki/DULG/UBootBootCountLimit
3307 enable special bootcounter support on at91sam9xe based boards.
3309 enable special bootcounter support on blackfin based boards.
3311 enable special bootcounter support on da850 based boards.
3312 CONFIG_BOOTCOUNT_RAM
3313 enable support for the bootcounter in RAM
3314 CONFIG_BOOTCOUNT_I2C
3315 enable support for the bootcounter on an i2c (like RTC) device.
3316 CONFIG_SYS_I2C_RTC_ADDR = i2c chip address
3317 CONFIG_SYS_BOOTCOUNT_ADDR = i2c addr which is used for
3319 CONFIG_BOOTCOUNT_ALEN = address len
3321 - Show boot progress:
3322 CONFIG_SHOW_BOOT_PROGRESS
3324 Defining this option allows to add some board-
3325 specific code (calling a user-provided function
3326 "show_boot_progress(int)") that enables you to show
3327 the system's boot progress on some display (for
3328 example, some LED's) on your board. At the moment,
3329 the following checkpoints are implemented:
3332 Legacy uImage format:
3335 1 common/cmd_bootm.c before attempting to boot an image
3336 -1 common/cmd_bootm.c Image header has bad magic number
3337 2 common/cmd_bootm.c Image header has correct magic number
3338 -2 common/cmd_bootm.c Image header has bad checksum
3339 3 common/cmd_bootm.c Image header has correct checksum
3340 -3 common/cmd_bootm.c Image data has bad checksum
3341 4 common/cmd_bootm.c Image data has correct checksum
3342 -4 common/cmd_bootm.c Image is for unsupported architecture
3343 5 common/cmd_bootm.c Architecture check OK
3344 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
3345 6 common/cmd_bootm.c Image Type check OK
3346 -6 common/cmd_bootm.c gunzip uncompression error
3347 -7 common/cmd_bootm.c Unimplemented compression type
3348 7 common/cmd_bootm.c Uncompression OK
3349 8 common/cmd_bootm.c No uncompress/copy overwrite error
3350 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
3352 9 common/image.c Start initial ramdisk verification
3353 -10 common/image.c Ramdisk header has bad magic number
3354 -11 common/image.c Ramdisk header has bad checksum
3355 10 common/image.c Ramdisk header is OK
3356 -12 common/image.c Ramdisk data has bad checksum
3357 11 common/image.c Ramdisk data has correct checksum
3358 12 common/image.c Ramdisk verification complete, start loading
3359 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
3360 13 common/image.c Start multifile image verification
3361 14 common/image.c No initial ramdisk, no multifile, continue.
3363 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
3365 -30 arch/powerpc/lib/board.c Fatal error, hang the system
3366 -31 post/post.c POST test failed, detected by post_output_backlog()
3367 -32 post/post.c POST test failed, detected by post_run_single()
3369 34 common/cmd_doc.c before loading a Image from a DOC device
3370 -35 common/cmd_doc.c Bad usage of "doc" command
3371 35 common/cmd_doc.c correct usage of "doc" command
3372 -36 common/cmd_doc.c No boot device
3373 36 common/cmd_doc.c correct boot device
3374 -37 common/cmd_doc.c Unknown Chip ID on boot device
3375 37 common/cmd_doc.c correct chip ID found, device available
3376 -38 common/cmd_doc.c Read Error on boot device
3377 38 common/cmd_doc.c reading Image header from DOC device OK
3378 -39 common/cmd_doc.c Image header has bad magic number
3379 39 common/cmd_doc.c Image header has correct magic number
3380 -40 common/cmd_doc.c Error reading Image from DOC device
3381 40 common/cmd_doc.c Image header has correct magic number
3382 41 common/cmd_ide.c before loading a Image from a IDE device
3383 -42 common/cmd_ide.c Bad usage of "ide" command
3384 42 common/cmd_ide.c correct usage of "ide" command
3385 -43 common/cmd_ide.c No boot device
3386 43 common/cmd_ide.c boot device found
3387 -44 common/cmd_ide.c Device not available
3388 44 common/cmd_ide.c Device available
3389 -45 common/cmd_ide.c wrong partition selected
3390 45 common/cmd_ide.c partition selected
3391 -46 common/cmd_ide.c Unknown partition table
3392 46 common/cmd_ide.c valid partition table found
3393 -47 common/cmd_ide.c Invalid partition type
3394 47 common/cmd_ide.c correct partition type
3395 -48 common/cmd_ide.c Error reading Image Header on boot device
3396 48 common/cmd_ide.c reading Image Header from IDE device OK
3397 -49 common/cmd_ide.c Image header has bad magic number
3398 49 common/cmd_ide.c Image header has correct magic number
3399 -50 common/cmd_ide.c Image header has bad checksum
3400 50 common/cmd_ide.c Image header has correct checksum
3401 -51 common/cmd_ide.c Error reading Image from IDE device
3402 51 common/cmd_ide.c reading Image from IDE device OK
3403 52 common/cmd_nand.c before loading a Image from a NAND device
3404 -53 common/cmd_nand.c Bad usage of "nand" command
3405 53 common/cmd_nand.c correct usage of "nand" command
3406 -54 common/cmd_nand.c No boot device
3407 54 common/cmd_nand.c boot device found
3408 -55 common/cmd_nand.c Unknown Chip ID on boot device
3409 55 common/cmd_nand.c correct chip ID found, device available
3410 -56 common/cmd_nand.c Error reading Image Header on boot device
3411 56 common/cmd_nand.c reading Image Header from NAND device OK
3412 -57 common/cmd_nand.c Image header has bad magic number
3413 57 common/cmd_nand.c Image header has correct magic number
3414 -58 common/cmd_nand.c Error reading Image from NAND device
3415 58 common/cmd_nand.c reading Image from NAND device OK
3417 -60 common/env_common.c Environment has a bad CRC, using default
3419 64 net/eth.c starting with Ethernet configuration.
3420 -64 net/eth.c no Ethernet found.
3421 65 net/eth.c Ethernet found.
3423 -80 common/cmd_net.c usage wrong
3424 80 common/cmd_net.c before calling net_loop()
3425 -81 common/cmd_net.c some error in net_loop() occurred
3426 81 common/cmd_net.c net_loop() back without error
3427 -82 common/cmd_net.c size == 0 (File with size 0 loaded)
3428 82 common/cmd_net.c trying automatic boot
3429 83 common/cmd_net.c running "source" command
3430 -83 common/cmd_net.c some error in automatic boot or "source" command
3431 84 common/cmd_net.c end without errors
3436 100 common/cmd_bootm.c Kernel FIT Image has correct format
3437 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
3438 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
3439 -101 common/cmd_bootm.c Can't get configuration for kernel subimage
3440 102 common/cmd_bootm.c Kernel unit name specified
3441 -103 common/cmd_bootm.c Can't get kernel subimage node offset
3442 103 common/cmd_bootm.c Found configuration node
3443 104 common/cmd_bootm.c Got kernel subimage node offset
3444 -104 common/cmd_bootm.c Kernel subimage hash verification failed
3445 105 common/cmd_bootm.c Kernel subimage hash verification OK
3446 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
3447 106 common/cmd_bootm.c Architecture check OK
3448 -106 common/cmd_bootm.c Kernel subimage has wrong type
3449 107 common/cmd_bootm.c Kernel subimage type OK
3450 -107 common/cmd_bootm.c Can't get kernel subimage data/size
3451 108 common/cmd_bootm.c Got kernel subimage data/size
3452 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
3453 -109 common/cmd_bootm.c Can't get kernel subimage type
3454 -110 common/cmd_bootm.c Can't get kernel subimage comp
3455 -111 common/cmd_bootm.c Can't get kernel subimage os
3456 -112 common/cmd_bootm.c Can't get kernel subimage load address
3457 -113 common/cmd_bootm.c Image uncompress/copy overwrite error
3459 120 common/image.c Start initial ramdisk verification
3460 -120 common/image.c Ramdisk FIT image has incorrect format
3461 121 common/image.c Ramdisk FIT image has correct format
3462 122 common/image.c No ramdisk subimage unit name, using configuration
3463 -122 common/image.c Can't get configuration for ramdisk subimage
3464 123 common/image.c Ramdisk unit name specified
3465 -124 common/image.c Can't get ramdisk subimage node offset
3466 125 common/image.c Got ramdisk subimage node offset
3467 -125 common/image.c Ramdisk subimage hash verification failed
3468 126 common/image.c Ramdisk subimage hash verification OK
3469 -126 common/image.c Ramdisk subimage for unsupported architecture
3470 127 common/image.c Architecture check OK
3471 -127 common/image.c Can't get ramdisk subimage data/size
3472 128 common/image.c Got ramdisk subimage data/size
3473 129 common/image.c Can't get ramdisk load address
3474 -129 common/image.c Got ramdisk load address
3476 -130 common/cmd_doc.c Incorrect FIT image format
3477 131 common/cmd_doc.c FIT image format OK
3479 -140 common/cmd_ide.c Incorrect FIT image format
3480 141 common/cmd_ide.c FIT image format OK
3482 -150 common/cmd_nand.c Incorrect FIT image format
3483 151 common/cmd_nand.c FIT image format OK
3485 - legacy image format:
3486 CONFIG_IMAGE_FORMAT_LEGACY
3487 enables the legacy image format support in U-Boot.
3490 enabled if CONFIG_FIT_SIGNATURE is not defined.
3492 CONFIG_DISABLE_IMAGE_LEGACY
3493 disable the legacy image format
3495 This define is introduced, as the legacy image format is
3496 enabled per default for backward compatibility.
3498 - FIT image support:
3500 Enable support for the FIT uImage format.
3502 CONFIG_FIT_BEST_MATCH
3503 When no configuration is explicitly selected, default to the
3504 one whose fdt's compatibility field best matches that of
3505 U-Boot itself. A match is considered "best" if it matches the
3506 most specific compatibility entry of U-Boot's fdt's root node.
3507 The order of entries in the configuration's fdt is ignored.
3509 CONFIG_FIT_SIGNATURE
3510 This option enables signature verification of FIT uImages,
3511 using a hash signed and verified using RSA. If
3512 CONFIG_SHA_PROG_HW_ACCEL is defined, i.e support for progressive
3513 hashing is available using hardware, RSA library will use it.
3514 See doc/uImage.FIT/signature.txt for more details.
3516 WARNING: When relying on signed FIT images with required
3517 signature check the legacy image format is default
3518 disabled. If a board need legacy image format support
3519 enable this through CONFIG_IMAGE_FORMAT_LEGACY
3521 CONFIG_FIT_DISABLE_SHA256
3522 Supporting SHA256 hashes has quite an impact on binary size.
3523 For constrained systems sha256 hash support can be disabled
3526 - Standalone program support:
3527 CONFIG_STANDALONE_LOAD_ADDR
3529 This option defines a board specific value for the
3530 address where standalone program gets loaded, thus
3531 overwriting the architecture dependent default
3534 - Frame Buffer Address:
3537 Define CONFIG_FB_ADDR if you want to use specific
3538 address for frame buffer. This is typically the case
3539 when using a graphics controller has separate video
3540 memory. U-Boot will then place the frame buffer at
3541 the given address instead of dynamically reserving it
3542 in system RAM by calling lcd_setmem(), which grabs
3543 the memory for the frame buffer depending on the
3544 configured panel size.
3546 Please see board_init_f function.
3548 - Automatic software updates via TFTP server
3550 CONFIG_UPDATE_TFTP_CNT_MAX
3551 CONFIG_UPDATE_TFTP_MSEC_MAX
3553 These options enable and control the auto-update feature;
3554 for a more detailed description refer to doc/README.update.
3556 - MTD Support (mtdparts command, UBI support)
3559 Adds the MTD device infrastructure from the Linux kernel.
3560 Needed for mtdparts command support.
3562 CONFIG_MTD_PARTITIONS
3564 Adds the MTD partitioning infrastructure from the Linux
3565 kernel. Needed for UBI support.
3570 Adds commands for interacting with MTD partitions formatted
3571 with the UBI flash translation layer
3573 Requires also defining CONFIG_RBTREE
3575 CONFIG_UBI_SILENCE_MSG
3577 Make the verbose messages from UBI stop printing. This leaves
3578 warnings and errors enabled.
3581 CONFIG_MTD_UBI_WL_THRESHOLD
3582 This parameter defines the maximum difference between the highest
3583 erase counter value and the lowest erase counter value of eraseblocks
3584 of UBI devices. When this threshold is exceeded, UBI starts performing
3585 wear leveling by means of moving data from eraseblock with low erase
3586 counter to eraseblocks with high erase counter.
3588 The default value should be OK for SLC NAND flashes, NOR flashes and
3589 other flashes which have eraseblock life-cycle 100000 or more.
3590 However, in case of MLC NAND flashes which typically have eraseblock
3591 life-cycle less than 10000, the threshold should be lessened (e.g.,
3592 to 128 or 256, although it does not have to be power of 2).
3596 CONFIG_MTD_UBI_BEB_LIMIT
3597 This option specifies the maximum bad physical eraseblocks UBI
3598 expects on the MTD device (per 1024 eraseblocks). If the
3599 underlying flash does not admit of bad eraseblocks (e.g. NOR
3600 flash), this value is ignored.
3602 NAND datasheets often specify the minimum and maximum NVM
3603 (Number of Valid Blocks) for the flashes' endurance lifetime.
3604 The maximum expected bad eraseblocks per 1024 eraseblocks
3605 then can be calculated as "1024 * (1 - MinNVB / MaxNVB)",
3606 which gives 20 for most NANDs (MaxNVB is basically the total
3607 count of eraseblocks on the chip).
3609 To put it differently, if this value is 20, UBI will try to
3610 reserve about 1.9% of physical eraseblocks for bad blocks
3611 handling. And that will be 1.9% of eraseblocks on the entire
3612 NAND chip, not just the MTD partition UBI attaches. This means
3613 that if you have, say, a NAND flash chip admits maximum 40 bad
3614 eraseblocks, and it is split on two MTD partitions of the same
3615 size, UBI will reserve 40 eraseblocks when attaching a
3620 CONFIG_MTD_UBI_FASTMAP
3621 Fastmap is a mechanism which allows attaching an UBI device
3622 in nearly constant time. Instead of scanning the whole MTD device it
3623 only has to locate a checkpoint (called fastmap) on the device.
3624 The on-flash fastmap contains all information needed to attach
3625 the device. Using fastmap makes only sense on large devices where
3626 attaching by scanning takes long. UBI will not automatically install
3627 a fastmap on old images, but you can set the UBI parameter
3628 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT to 1 if you want so. Please note
3629 that fastmap-enabled images are still usable with UBI implementations
3630 without fastmap support. On typical flash devices the whole fastmap
3631 fits into one PEB. UBI will reserve PEBs to hold two fastmaps.
3633 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT
3634 Set this parameter to enable fastmap automatically on images
3641 Adds commands for interacting with UBI volumes formatted as
3642 UBIFS. UBIFS is read-only in u-boot.
3644 Requires UBI support as well as CONFIG_LZO
3646 CONFIG_UBIFS_SILENCE_MSG
3648 Make the verbose messages from UBIFS stop printing. This leaves
3649 warnings and errors enabled.
3653 Enable building of SPL globally.
3656 LDSCRIPT for linking the SPL binary.
3658 CONFIG_SPL_MAX_FOOTPRINT
3659 Maximum size in memory allocated to the SPL, BSS included.
3660 When defined, the linker checks that the actual memory
3661 used by SPL from _start to __bss_end does not exceed it.
3662 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
3663 must not be both defined at the same time.
3666 Maximum size of the SPL image (text, data, rodata, and
3667 linker lists sections), BSS excluded.
3668 When defined, the linker checks that the actual size does
3671 CONFIG_SPL_TEXT_BASE
3672 TEXT_BASE for linking the SPL binary.
3674 CONFIG_SPL_RELOC_TEXT_BASE
3675 Address to relocate to. If unspecified, this is equal to
3676 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done).
3678 CONFIG_SPL_BSS_START_ADDR
3679 Link address for the BSS within the SPL binary.
3681 CONFIG_SPL_BSS_MAX_SIZE
3682 Maximum size in memory allocated to the SPL BSS.
3683 When defined, the linker checks that the actual memory used
3684 by SPL from __bss_start to __bss_end does not exceed it.
3685 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
3686 must not be both defined at the same time.
3689 Adress of the start of the stack SPL will use
3691 CONFIG_SPL_PANIC_ON_RAW_IMAGE
3692 When defined, SPL will panic() if the image it has
3693 loaded does not have a signature.
3694 Defining this is useful when code which loads images
3695 in SPL cannot guarantee that absolutely all read errors
3697 An example is the LPC32XX MLC NAND driver, which will
3698 consider that a completely unreadable NAND block is bad,
3699 and thus should be skipped silently.
3701 CONFIG_SPL_RELOC_STACK
3702 Adress of the start of the stack SPL will use after
3703 relocation. If unspecified, this is equal to
3706 CONFIG_SYS_SPL_MALLOC_START
3707 Starting address of the malloc pool used in SPL.
3709 CONFIG_SYS_SPL_MALLOC_SIZE
3710 The size of the malloc pool used in SPL.
3712 CONFIG_SPL_FRAMEWORK
3713 Enable the SPL framework under common/. This framework
3714 supports MMC, NAND and YMODEM loading of U-Boot and NAND
3715 NAND loading of the Linux Kernel.
3718 Enable booting directly to an OS from SPL.
3719 See also: doc/README.falcon
3721 CONFIG_SPL_DISPLAY_PRINT
3722 For ARM, enable an optional function to print more information
3723 about the running system.
3725 CONFIG_SPL_INIT_MINIMAL
3726 Arch init code should be built for a very small image
3728 CONFIG_SPL_LIBCOMMON_SUPPORT
3729 Support for common/libcommon.o in SPL binary
3731 CONFIG_SPL_LIBDISK_SUPPORT
3732 Support for disk/libdisk.o in SPL binary
3734 CONFIG_SPL_I2C_SUPPORT
3735 Support for drivers/i2c/libi2c.o in SPL binary
3737 CONFIG_SPL_GPIO_SUPPORT
3738 Support for drivers/gpio/libgpio.o in SPL binary
3740 CONFIG_SPL_MMC_SUPPORT
3741 Support for drivers/mmc/libmmc.o in SPL binary
3743 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR,
3744 CONFIG_SYS_U_BOOT_MAX_SIZE_SECTORS,
3745 Address and partition on the MMC to load U-Boot from
3746 when the MMC is being used in raw mode.
3748 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_PARTITION
3749 Partition on the MMC to load U-Boot from when the MMC is being
3752 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR
3753 Sector to load kernel uImage from when MMC is being
3754 used in raw mode (for Falcon mode)
3756 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR,
3757 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS
3758 Sector and number of sectors to load kernel argument
3759 parameters from when MMC is being used in raw mode
3762 CONFIG_SYS_MMCSD_FS_BOOT_PARTITION
3763 Partition on the MMC to load U-Boot from when the MMC is being
3766 CONFIG_SPL_FAT_SUPPORT
3767 Support for fs/fat/libfat.o in SPL binary
3769 CONFIG_SPL_EXT_SUPPORT
3770 Support for EXT filesystem in SPL binary
3772 CONFIG_SPL_FS_LOAD_PAYLOAD_NAME
3773 Filename to read to load U-Boot when reading from filesystem
3775 CONFIG_SPL_FS_LOAD_KERNEL_NAME
3776 Filename to read to load kernel uImage when reading
3777 from filesystem (for Falcon mode)
3779 CONFIG_SPL_FS_LOAD_ARGS_NAME
3780 Filename to read to load kernel argument parameters
3781 when reading from filesystem (for Falcon mode)
3783 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND
3784 Set this for NAND SPL on PPC mpc83xx targets, so that
3785 start.S waits for the rest of the SPL to load before
3786 continuing (the hardware starts execution after just
3787 loading the first page rather than the full 4K).
3789 CONFIG_SPL_SKIP_RELOCATE
3790 Avoid SPL relocation
3792 CONFIG_SPL_NAND_BASE
3793 Include nand_base.c in the SPL. Requires
3794 CONFIG_SPL_NAND_DRIVERS.
3796 CONFIG_SPL_NAND_DRIVERS
3797 SPL uses normal NAND drivers, not minimal drivers.
3800 Include standard software ECC in the SPL
3802 CONFIG_SPL_NAND_SIMPLE
3803 Support for NAND boot using simple NAND drivers that
3804 expose the cmd_ctrl() interface.
3806 CONFIG_SPL_MTD_SUPPORT
3807 Support for the MTD subsystem within SPL. Useful for
3808 environment on NAND support within SPL.
3810 CONFIG_SPL_NAND_RAW_ONLY
3811 Support to boot only raw u-boot.bin images. Use this only
3812 if you need to save space.
3814 CONFIG_SPL_MPC8XXX_INIT_DDR_SUPPORT
3815 Set for the SPL on PPC mpc8xxx targets, support for
3816 drivers/ddr/fsl/libddr.o in SPL binary.
3818 CONFIG_SPL_COMMON_INIT_DDR
3819 Set for common ddr init with serial presence detect in
3822 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
3823 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
3824 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
3825 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE,
3826 CONFIG_SYS_NAND_ECCBYTES
3827 Defines the size and behavior of the NAND that SPL uses
3830 CONFIG_SPL_NAND_BOOT
3831 Add support NAND boot
3833 CONFIG_SYS_NAND_U_BOOT_OFFS
3834 Location in NAND to read U-Boot from
3836 CONFIG_SYS_NAND_U_BOOT_DST
3837 Location in memory to load U-Boot to
3839 CONFIG_SYS_NAND_U_BOOT_SIZE
3840 Size of image to load
3842 CONFIG_SYS_NAND_U_BOOT_START
3843 Entry point in loaded image to jump to
3845 CONFIG_SYS_NAND_HW_ECC_OOBFIRST
3846 Define this if you need to first read the OOB and then the
3847 data. This is used, for example, on davinci platforms.
3849 CONFIG_SPL_OMAP3_ID_NAND
3850 Support for an OMAP3-specific set of functions to return the
3851 ID and MFR of the first attached NAND chip, if present.
3853 CONFIG_SPL_SERIAL_SUPPORT
3854 Support for drivers/serial/libserial.o in SPL binary
3856 CONFIG_SPL_SPI_FLASH_SUPPORT
3857 Support for drivers/mtd/spi/libspi_flash.o in SPL binary
3859 CONFIG_SPL_SPI_SUPPORT
3860 Support for drivers/spi/libspi.o in SPL binary
3862 CONFIG_SPL_RAM_DEVICE
3863 Support for running image already present in ram, in SPL binary
3865 CONFIG_SPL_LIBGENERIC_SUPPORT
3866 Support for lib/libgeneric.o in SPL binary
3868 CONFIG_SPL_ENV_SUPPORT
3869 Support for the environment operating in SPL binary
3871 CONFIG_SPL_NET_SUPPORT
3872 Support for the net/libnet.o in SPL binary.
3873 It conflicts with SPL env from storage medium specified by
3874 CONFIG_ENV_IS_xxx but CONFIG_ENV_IS_NOWHERE
3877 Image offset to which the SPL should be padded before appending
3878 the SPL payload. By default, this is defined as
3879 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
3880 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
3881 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
3884 Final target image containing SPL and payload. Some SPLs
3885 use an arch-specific makefile fragment instead, for
3886 example if more than one image needs to be produced.
3888 CONFIG_FIT_SPL_PRINT
3889 Printing information about a FIT image adds quite a bit of
3890 code to SPL. So this is normally disabled in SPL. Use this
3891 option to re-enable it. This will affect the output of the
3892 bootm command when booting a FIT image.
3896 Enable building of TPL globally.
3899 Image offset to which the TPL should be padded before appending
3900 the TPL payload. By default, this is defined as
3901 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
3902 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
3903 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
3908 [so far only for SMDK2400 boards]
3910 - Modem support enable:
3911 CONFIG_MODEM_SUPPORT
3913 - RTS/CTS Flow control enable:
3916 - Modem debug support:
3917 CONFIG_MODEM_SUPPORT_DEBUG
3919 Enables debugging stuff (char screen[1024], dbg())
3920 for modem support. Useful only with BDI2000.
3922 - Interrupt support (PPC):
3924 There are common interrupt_init() and timer_interrupt()
3925 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
3926 for CPU specific initialization. interrupt_init_cpu()
3927 should set decrementer_count to appropriate value. If
3928 CPU resets decrementer automatically after interrupt
3929 (ppc4xx) it should set decrementer_count to zero.
3930 timer_interrupt() calls timer_interrupt_cpu() for CPU
3931 specific handling. If board has watchdog / status_led
3932 / other_activity_monitor it works automatically from
3933 general timer_interrupt().
3937 In the target system modem support is enabled when a
3938 specific key (key combination) is pressed during
3939 power-on. Otherwise U-Boot will boot normally
3940 (autoboot). The key_pressed() function is called from
3941 board_init(). Currently key_pressed() is a dummy
3942 function, returning 1 and thus enabling modem
3945 If there are no modem init strings in the
3946 environment, U-Boot proceed to autoboot; the
3947 previous output (banner, info printfs) will be
3950 See also: doc/README.Modem
3952 Board initialization settings:
3953 ------------------------------
3955 During Initialization u-boot calls a number of board specific functions
3956 to allow the preparation of board specific prerequisites, e.g. pin setup
3957 before drivers are initialized. To enable these callbacks the
3958 following configuration macros have to be defined. Currently this is
3959 architecture specific, so please check arch/your_architecture/lib/board.c
3960 typically in board_init_f() and board_init_r().
3962 - CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
3963 - CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
3964 - CONFIG_BOARD_LATE_INIT: Call board_late_init()
3965 - CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init()
3967 Configuration Settings:
3968 -----------------------
3970 - CONFIG_SYS_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit.
3971 Optionally it can be defined to support 64-bit memory commands.
3973 - CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
3974 undefine this when you're short of memory.
3976 - CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
3977 width of the commands listed in the 'help' command output.
3979 - CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
3980 prompt for user input.
3982 - CONFIG_SYS_CBSIZE: Buffer size for input from the Console
3984 - CONFIG_SYS_PBSIZE: Buffer size for Console output
3986 - CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
3988 - CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
3989 the application (usually a Linux kernel) when it is
3992 - CONFIG_SYS_BAUDRATE_TABLE:
3993 List of legal baudrate settings for this board.
3995 - CONFIG_SYS_CONSOLE_INFO_QUIET
3996 Suppress display of console information at boot.
3998 - CONFIG_SYS_CONSOLE_IS_IN_ENV
3999 If the board specific function
4000 extern int overwrite_console (void);
4001 returns 1, the stdin, stderr and stdout are switched to the
4002 serial port, else the settings in the environment are used.
4004 - CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE
4005 Enable the call to overwrite_console().
4007 - CONFIG_SYS_CONSOLE_ENV_OVERWRITE
4008 Enable overwrite of previous console environment settings.
4010 - CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
4011 Begin and End addresses of the area used by the
4014 - CONFIG_SYS_ALT_MEMTEST:
4015 Enable an alternate, more extensive memory test.
4017 - CONFIG_SYS_MEMTEST_SCRATCH:
4018 Scratch address used by the alternate memory test
4019 You only need to set this if address zero isn't writeable
4021 - CONFIG_SYS_MEM_TOP_HIDE (PPC only):
4022 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
4023 this specified memory area will get subtracted from the top
4024 (end) of RAM and won't get "touched" at all by U-Boot. By
4025 fixing up gd->ram_size the Linux kernel should gets passed
4026 the now "corrected" memory size and won't touch it either.
4027 This should work for arch/ppc and arch/powerpc. Only Linux
4028 board ports in arch/powerpc with bootwrapper support that
4029 recalculate the memory size from the SDRAM controller setup
4030 will have to get fixed in Linux additionally.
4032 This option can be used as a workaround for the 440EPx/GRx
4033 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
4036 WARNING: Please make sure that this value is a multiple of
4037 the Linux page size (normally 4k). If this is not the case,
4038 then the end address of the Linux memory will be located at a
4039 non page size aligned address and this could cause major
4042 - CONFIG_SYS_LOADS_BAUD_CHANGE:
4043 Enable temporary baudrate change while serial download
4045 - CONFIG_SYS_SDRAM_BASE:
4046 Physical start address of SDRAM. _Must_ be 0 here.
4048 - CONFIG_SYS_MBIO_BASE:
4049 Physical start address of Motherboard I/O (if using a
4052 - CONFIG_SYS_FLASH_BASE:
4053 Physical start address of Flash memory.
4055 - CONFIG_SYS_MONITOR_BASE:
4056 Physical start address of boot monitor code (set by
4057 make config files to be same as the text base address
4058 (CONFIG_SYS_TEXT_BASE) used when linking) - same as
4059 CONFIG_SYS_FLASH_BASE when booting from flash.
4061 - CONFIG_SYS_MONITOR_LEN:
4062 Size of memory reserved for monitor code, used to
4063 determine _at_compile_time_ (!) if the environment is
4064 embedded within the U-Boot image, or in a separate
4067 - CONFIG_SYS_MALLOC_LEN:
4068 Size of DRAM reserved for malloc() use.
4070 - CONFIG_SYS_MALLOC_F_LEN
4071 Size of the malloc() pool for use before relocation. If
4072 this is defined, then a very simple malloc() implementation
4073 will become available before relocation. The address is just
4074 below the global data, and the stack is moved down to make
4077 This feature allocates regions with increasing addresses
4078 within the region. calloc() is supported, but realloc()
4079 is not available. free() is supported but does nothing.
4080 The memory will be freed (or in fact just forgotten) when
4081 U-Boot relocates itself.
4083 Pre-relocation malloc() is only supported on ARM and sandbox
4084 at present but is fairly easy to enable for other archs.
4086 - CONFIG_SYS_MALLOC_SIMPLE
4087 Provides a simple and small malloc() and calloc() for those
4088 boards which do not use the full malloc in SPL (which is
4089 enabled with CONFIG_SYS_SPL_MALLOC_START).
4091 - CONFIG_SYS_NONCACHED_MEMORY:
4092 Size of non-cached memory area. This area of memory will be
4093 typically located right below the malloc() area and mapped
4094 uncached in the MMU. This is useful for drivers that would
4095 otherwise require a lot of explicit cache maintenance. For
4096 some drivers it's also impossible to properly maintain the
4097 cache. For example if the regions that need to be flushed
4098 are not a multiple of the cache-line size, *and* padding
4099 cannot be allocated between the regions to align them (i.e.
4100 if the HW requires a contiguous array of regions, and the
4101 size of each region is not cache-aligned), then a flush of
4102 one region may result in overwriting data that hardware has
4103 written to another region in the same cache-line. This can
4104 happen for example in network drivers where descriptors for
4105 buffers are typically smaller than the CPU cache-line (e.g.
4106 16 bytes vs. 32 or 64 bytes).
4108 Non-cached memory is only supported on 32-bit ARM at present.
4110 - CONFIG_SYS_BOOTM_LEN:
4111 Normally compressed uImages are limited to an
4112 uncompressed size of 8 MBytes. If this is not enough,
4113 you can define CONFIG_SYS_BOOTM_LEN in your board config file
4114 to adjust this setting to your needs.
4116 - CONFIG_SYS_BOOTMAPSZ:
4117 Maximum size of memory mapped by the startup code of
4118 the Linux kernel; all data that must be processed by
4119 the Linux kernel (bd_info, boot arguments, FDT blob if
4120 used) must be put below this limit, unless "bootm_low"
4121 environment variable is defined and non-zero. In such case
4122 all data for the Linux kernel must be between "bootm_low"
4123 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
4124 variable "bootm_mapsize" will override the value of
4125 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
4126 then the value in "bootm_size" will be used instead.
4128 - CONFIG_SYS_BOOT_RAMDISK_HIGH:
4129 Enable initrd_high functionality. If defined then the
4130 initrd_high feature is enabled and the bootm ramdisk subcommand
4133 - CONFIG_SYS_BOOT_GET_CMDLINE:
4134 Enables allocating and saving kernel cmdline in space between
4135 "bootm_low" and "bootm_low" + BOOTMAPSZ.
4137 - CONFIG_SYS_BOOT_GET_KBD:
4138 Enables allocating and saving a kernel copy of the bd_info in
4139 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
4141 - CONFIG_SYS_MAX_FLASH_BANKS:
4142 Max number of Flash memory banks
4144 - CONFIG_SYS_MAX_FLASH_SECT:
4145 Max number of sectors on a Flash chip
4147 - CONFIG_SYS_FLASH_ERASE_TOUT:
4148 Timeout for Flash erase operations (in ms)
4150 - CONFIG_SYS_FLASH_WRITE_TOUT:
4151 Timeout for Flash write operations (in ms)
4153 - CONFIG_SYS_FLASH_LOCK_TOUT
4154 Timeout for Flash set sector lock bit operation (in ms)
4156 - CONFIG_SYS_FLASH_UNLOCK_TOUT
4157 Timeout for Flash clear lock bits operation (in ms)
4159 - CONFIG_SYS_FLASH_PROTECTION
4160 If defined, hardware flash sectors protection is used
4161 instead of U-Boot software protection.
4163 - CONFIG_SYS_DIRECT_FLASH_TFTP:
4165 Enable TFTP transfers directly to flash memory;
4166 without this option such a download has to be
4167 performed in two steps: (1) download to RAM, and (2)
4168 copy from RAM to flash.
4170 The two-step approach is usually more reliable, since
4171 you can check if the download worked before you erase
4172 the flash, but in some situations (when system RAM is
4173 too limited to allow for a temporary copy of the
4174 downloaded image) this option may be very useful.
4176 - CONFIG_SYS_FLASH_CFI:
4177 Define if the flash driver uses extra elements in the
4178 common flash structure for storing flash geometry.
4180 - CONFIG_FLASH_CFI_DRIVER
4181 This option also enables the building of the cfi_flash driver
4182 in the drivers directory
4184 - CONFIG_FLASH_CFI_MTD
4185 This option enables the building of the cfi_mtd driver
4186 in the drivers directory. The driver exports CFI flash
4189 - CONFIG_SYS_FLASH_USE_BUFFER_WRITE
4190 Use buffered writes to flash.
4192 - CONFIG_FLASH_SPANSION_S29WS_N
4193 s29ws-n MirrorBit flash has non-standard addresses for buffered
4196 - CONFIG_SYS_FLASH_QUIET_TEST
4197 If this option is defined, the common CFI flash doesn't
4198 print it's warning upon not recognized FLASH banks. This
4199 is useful, if some of the configured banks are only
4200 optionally available.
4202 - CONFIG_FLASH_SHOW_PROGRESS
4203 If defined (must be an integer), print out countdown
4204 digits and dots. Recommended value: 45 (9..1) for 80
4205 column displays, 15 (3..1) for 40 column displays.
4207 - CONFIG_FLASH_VERIFY
4208 If defined, the content of the flash (destination) is compared
4209 against the source after the write operation. An error message
4210 will be printed when the contents are not identical.
4211 Please note that this option is useless in nearly all cases,
4212 since such flash programming errors usually are detected earlier
4213 while unprotecting/erasing/programming. Please only enable
4214 this option if you really know what you are doing.
4216 - CONFIG_SYS_RX_ETH_BUFFER:
4217 Defines the number of Ethernet receive buffers. On some
4218 Ethernet controllers it is recommended to set this value
4219 to 8 or even higher (EEPRO100 or 405 EMAC), since all
4220 buffers can be full shortly after enabling the interface
4221 on high Ethernet traffic.
4222 Defaults to 4 if not defined.
4224 - CONFIG_ENV_MAX_ENTRIES
4226 Maximum number of entries in the hash table that is used
4227 internally to store the environment settings. The default
4228 setting is supposed to be generous and should work in most
4229 cases. This setting can be used to tune behaviour; see
4230 lib/hashtable.c for details.
4232 - CONFIG_ENV_FLAGS_LIST_DEFAULT
4233 - CONFIG_ENV_FLAGS_LIST_STATIC
4234 Enable validation of the values given to environment variables when
4235 calling env set. Variables can be restricted to only decimal,
4236 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined,
4237 the variables can also be restricted to IP address or MAC address.
4239 The format of the list is:
4240 type_attribute = [s|d|x|b|i|m]
4241 access_attribute = [a|r|o|c]
4242 attributes = type_attribute[access_attribute]
4243 entry = variable_name[:attributes]
4246 The type attributes are:
4247 s - String (default)
4250 b - Boolean ([1yYtT|0nNfF])
4254 The access attributes are:
4260 - CONFIG_ENV_FLAGS_LIST_DEFAULT
4261 Define this to a list (string) to define the ".flags"
4262 environment variable in the default or embedded environment.
4264 - CONFIG_ENV_FLAGS_LIST_STATIC
4265 Define this to a list (string) to define validation that
4266 should be done if an entry is not found in the ".flags"
4267 environment variable. To override a setting in the static
4268 list, simply add an entry for the same variable name to the
4271 If CONFIG_REGEX is defined, the variable_name above is evaluated as a
4272 regular expression. This allows multiple variables to define the same
4273 flags without explicitly listing them for each variable.
4275 - CONFIG_ENV_ACCESS_IGNORE_FORCE
4276 If defined, don't allow the -f switch to env set override variable
4279 - CONFIG_SYS_GENERIC_BOARD
4280 This selects the architecture-generic board system instead of the
4281 architecture-specific board files. It is intended to move boards
4282 to this new framework over time. Defining this will disable the
4283 arch/foo/lib/board.c file and use common/board_f.c and
4284 common/board_r.c instead. To use this option your architecture
4285 must support it (i.e. must select HAVE_GENERIC_BOARD in arch/Kconfig).
4286 If you find problems enabling this option on your board please report
4287 the problem and send patches!
4289 - CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC (OMAP only)
4290 This is set by OMAP boards for the max time that reset should
4291 be asserted. See doc/README.omap-reset-time for details on how
4292 the value can be calculated on a given board.
4295 If stdint.h is available with your toolchain you can define this
4296 option to enable it. You can provide option 'USE_STDINT=1' when
4297 building U-Boot to enable this.
4299 The following definitions that deal with the placement and management
4300 of environment data (variable area); in general, we support the
4301 following configurations:
4303 - CONFIG_BUILD_ENVCRC:
4305 Builds up envcrc with the target environment so that external utils
4306 may easily extract it and embed it in final U-Boot images.
4308 - CONFIG_ENV_IS_IN_FLASH:
4310 Define this if the environment is in flash memory.
4312 a) The environment occupies one whole flash sector, which is
4313 "embedded" in the text segment with the U-Boot code. This
4314 happens usually with "bottom boot sector" or "top boot
4315 sector" type flash chips, which have several smaller
4316 sectors at the start or the end. For instance, such a
4317 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
4318 such a case you would place the environment in one of the
4319 4 kB sectors - with U-Boot code before and after it. With
4320 "top boot sector" type flash chips, you would put the
4321 environment in one of the last sectors, leaving a gap
4322 between U-Boot and the environment.
4324 - CONFIG_ENV_OFFSET:
4326 Offset of environment data (variable area) to the
4327 beginning of flash memory; for instance, with bottom boot
4328 type flash chips the second sector can be used: the offset
4329 for this sector is given here.
4331 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE.
4335 This is just another way to specify the start address of
4336 the flash sector containing the environment (instead of
4339 - CONFIG_ENV_SECT_SIZE:
4341 Size of the sector containing the environment.
4344 b) Sometimes flash chips have few, equal sized, BIG sectors.
4345 In such a case you don't want to spend a whole sector for
4350 If you use this in combination with CONFIG_ENV_IS_IN_FLASH
4351 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part
4352 of this flash sector for the environment. This saves
4353 memory for the RAM copy of the environment.
4355 It may also save flash memory if you decide to use this
4356 when your environment is "embedded" within U-Boot code,
4357 since then the remainder of the flash sector could be used
4358 for U-Boot code. It should be pointed out that this is
4359 STRONGLY DISCOURAGED from a robustness point of view:
4360 updating the environment in flash makes it always
4361 necessary to erase the WHOLE sector. If something goes
4362 wrong before the contents has been restored from a copy in
4363 RAM, your target system will be dead.
4365 - CONFIG_ENV_ADDR_REDUND
4366 CONFIG_ENV_SIZE_REDUND
4368 These settings describe a second storage area used to hold
4369 a redundant copy of the environment data, so that there is
4370 a valid backup copy in case there is a power failure during
4371 a "saveenv" operation.
4373 BE CAREFUL! Any changes to the flash layout, and some changes to the
4374 source code will make it necessary to adapt <board>/u-boot.lds*
4378 - CONFIG_ENV_IS_IN_NVRAM:
4380 Define this if you have some non-volatile memory device
4381 (NVRAM, battery buffered SRAM) which you want to use for the
4387 These two #defines are used to determine the memory area you
4388 want to use for environment. It is assumed that this memory
4389 can just be read and written to, without any special
4392 BE CAREFUL! The first access to the environment happens quite early
4393 in U-Boot initialization (when we try to get the setting of for the
4394 console baudrate). You *MUST* have mapped your NVRAM area then, or
4397 Please note that even with NVRAM we still use a copy of the
4398 environment in RAM: we could work on NVRAM directly, but we want to
4399 keep settings there always unmodified except somebody uses "saveenv"
4400 to save the current settings.
4403 - CONFIG_ENV_IS_IN_EEPROM:
4405 Use this if you have an EEPROM or similar serial access
4406 device and a driver for it.
4408 - CONFIG_ENV_OFFSET:
4411 These two #defines specify the offset and size of the
4412 environment area within the total memory of your EEPROM.
4414 - CONFIG_SYS_I2C_EEPROM_ADDR:
4415 If defined, specified the chip address of the EEPROM device.
4416 The default address is zero.
4418 - CONFIG_SYS_I2C_EEPROM_BUS:
4419 If defined, specified the i2c bus of the EEPROM device.
4421 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS:
4422 If defined, the number of bits used to address bytes in a
4423 single page in the EEPROM device. A 64 byte page, for example
4424 would require six bits.
4426 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS:
4427 If defined, the number of milliseconds to delay between
4428 page writes. The default is zero milliseconds.
4430 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN:
4431 The length in bytes of the EEPROM memory array address. Note
4432 that this is NOT the chip address length!
4434 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW:
4435 EEPROM chips that implement "address overflow" are ones
4436 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
4437 address and the extra bits end up in the "chip address" bit
4438 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
4441 Note that we consider the length of the address field to
4442 still be one byte because the extra address bits are hidden
4443 in the chip address.
4445 - CONFIG_SYS_EEPROM_SIZE:
4446 The size in bytes of the EEPROM device.
4448 - CONFIG_ENV_EEPROM_IS_ON_I2C
4449 define this, if you have I2C and SPI activated, and your
4450 EEPROM, which holds the environment, is on the I2C bus.
4452 - CONFIG_I2C_ENV_EEPROM_BUS
4453 if you have an Environment on an EEPROM reached over
4454 I2C muxes, you can define here, how to reach this
4455 EEPROM. For example:
4457 #define CONFIG_I2C_ENV_EEPROM_BUS 1
4459 EEPROM which holds the environment, is reached over
4460 a pca9547 i2c mux with address 0x70, channel 3.
4462 - CONFIG_ENV_IS_IN_DATAFLASH:
4464 Define this if you have a DataFlash memory device which you
4465 want to use for the environment.
4467 - CONFIG_ENV_OFFSET:
4471 These three #defines specify the offset and size of the
4472 environment area within the total memory of your DataFlash placed
4473 at the specified address.
4475 - CONFIG_ENV_IS_IN_SPI_FLASH:
4477 Define this if you have a SPI Flash memory device which you
4478 want to use for the environment.
4480 - CONFIG_ENV_OFFSET:
4483 These two #defines specify the offset and size of the
4484 environment area within the SPI Flash. CONFIG_ENV_OFFSET must be
4485 aligned to an erase sector boundary.
4487 - CONFIG_ENV_SECT_SIZE:
4489 Define the SPI flash's sector size.
4491 - CONFIG_ENV_OFFSET_REDUND (optional):
4493 This setting describes a second storage area of CONFIG_ENV_SIZE
4494 size used to hold a redundant copy of the environment data, so
4495 that there is a valid backup copy in case there is a power failure
4496 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be
4497 aligned to an erase sector boundary.
4499 - CONFIG_ENV_SPI_BUS (optional):
4500 - CONFIG_ENV_SPI_CS (optional):
4502 Define the SPI bus and chip select. If not defined they will be 0.
4504 - CONFIG_ENV_SPI_MAX_HZ (optional):
4506 Define the SPI max work clock. If not defined then use 1MHz.
4508 - CONFIG_ENV_SPI_MODE (optional):
4510 Define the SPI work mode. If not defined then use SPI_MODE_3.
4512 - CONFIG_ENV_IS_IN_REMOTE:
4514 Define this if you have a remote memory space which you
4515 want to use for the local device's environment.
4520 These two #defines specify the address and size of the
4521 environment area within the remote memory space. The
4522 local device can get the environment from remote memory
4523 space by SRIO or PCIE links.
4525 BE CAREFUL! For some special cases, the local device can not use
4526 "saveenv" command. For example, the local device will get the
4527 environment stored in a remote NOR flash by SRIO or PCIE link,
4528 but it can not erase, write this NOR flash by SRIO or PCIE interface.
4530 - CONFIG_ENV_IS_IN_NAND:
4532 Define this if you have a NAND device which you want to use
4533 for the environment.
4535 - CONFIG_ENV_OFFSET:
4538 These two #defines specify the offset and size of the environment
4539 area within the first NAND device. CONFIG_ENV_OFFSET must be
4540 aligned to an erase block boundary.
4542 - CONFIG_ENV_OFFSET_REDUND (optional):
4544 This setting describes a second storage area of CONFIG_ENV_SIZE
4545 size used to hold a redundant copy of the environment data, so
4546 that there is a valid backup copy in case there is a power failure
4547 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be
4548 aligned to an erase block boundary.
4550 - CONFIG_ENV_RANGE (optional):
4552 Specifies the length of the region in which the environment
4553 can be written. This should be a multiple of the NAND device's
4554 block size. Specifying a range with more erase blocks than
4555 are needed to hold CONFIG_ENV_SIZE allows bad blocks within
4556 the range to be avoided.
4558 - CONFIG_ENV_OFFSET_OOB (optional):
4560 Enables support for dynamically retrieving the offset of the
4561 environment from block zero's out-of-band data. The
4562 "nand env.oob" command can be used to record this offset.
4563 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when
4564 using CONFIG_ENV_OFFSET_OOB.
4566 - CONFIG_NAND_ENV_DST
4568 Defines address in RAM to which the nand_spl code should copy the
4569 environment. If redundant environment is used, it will be copied to
4570 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
4572 - CONFIG_ENV_IS_IN_UBI:
4574 Define this if you have an UBI volume that you want to use for the
4575 environment. This has the benefit of wear-leveling the environment
4576 accesses, which is important on NAND.
4578 - CONFIG_ENV_UBI_PART:
4580 Define this to a string that is the mtd partition containing the UBI.
4582 - CONFIG_ENV_UBI_VOLUME:
4584 Define this to the name of the volume that you want to store the
4587 - CONFIG_ENV_UBI_VOLUME_REDUND:
4589 Define this to the name of another volume to store a second copy of
4590 the environment in. This will enable redundant environments in UBI.
4591 It is assumed that both volumes are in the same MTD partition.
4593 - CONFIG_UBI_SILENCE_MSG
4594 - CONFIG_UBIFS_SILENCE_MSG
4596 You will probably want to define these to avoid a really noisy system
4597 when storing the env in UBI.
4599 - CONFIG_ENV_IS_IN_FAT:
4600 Define this if you want to use the FAT file system for the environment.
4602 - FAT_ENV_INTERFACE:
4604 Define this to a string that is the name of the block device.
4606 - FAT_ENV_DEV_AND_PART:
4608 Define this to a string to specify the partition of the device. It can
4611 "D:P", "D:0", "D", "D:" or "D:auto" (D, P are integers. And P >= 1)
4612 - "D:P": device D partition P. Error occurs if device D has no
4615 - "D" or "D:": device D partition 1 if device D has partition
4616 table, or the whole device D if has no partition
4618 - "D:auto": first partition in device D with bootable flag set.
4619 If none, first valid partition in device D. If no
4620 partition table then means device D.
4624 It's a string of the FAT file name. This file use to store the
4628 This should be defined. Otherwise it cannot save the environment file.
4630 - CONFIG_ENV_IS_IN_MMC:
4632 Define this if you have an MMC device which you want to use for the
4635 - CONFIG_SYS_MMC_ENV_DEV:
4637 Specifies which MMC device the environment is stored in.
4639 - CONFIG_SYS_MMC_ENV_PART (optional):
4641 Specifies which MMC partition the environment is stored in. If not
4642 set, defaults to partition 0, the user area. Common values might be
4643 1 (first MMC boot partition), 2 (second MMC boot partition).
4645 - CONFIG_ENV_OFFSET:
4648 These two #defines specify the offset and size of the environment
4649 area within the specified MMC device.
4651 If offset is positive (the usual case), it is treated as relative to
4652 the start of the MMC partition. If offset is negative, it is treated
4653 as relative to the end of the MMC partition. This can be useful if
4654 your board may be fitted with different MMC devices, which have
4655 different sizes for the MMC partitions, and you always want the
4656 environment placed at the very end of the partition, to leave the
4657 maximum possible space before it, to store other data.
4659 These two values are in units of bytes, but must be aligned to an
4660 MMC sector boundary.
4662 - CONFIG_ENV_OFFSET_REDUND (optional):
4664 Specifies a second storage area, of CONFIG_ENV_SIZE size, used to
4665 hold a redundant copy of the environment data. This provides a
4666 valid backup copy in case the other copy is corrupted, e.g. due
4667 to a power failure during a "saveenv" operation.
4669 This value may also be positive or negative; this is handled in the
4670 same way as CONFIG_ENV_OFFSET.
4672 This value is also in units of bytes, but must also be aligned to
4673 an MMC sector boundary.
4675 - CONFIG_ENV_SIZE_REDUND (optional):
4677 This value need not be set, even when CONFIG_ENV_OFFSET_REDUND is
4678 set. If this value is set, it must be set to the same value as
4681 - CONFIG_SYS_SPI_INIT_OFFSET
4683 Defines offset to the initial SPI buffer area in DPRAM. The
4684 area is used at an early stage (ROM part) if the environment
4685 is configured to reside in the SPI EEPROM: We need a 520 byte
4686 scratch DPRAM area. It is used between the two initialization
4687 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
4688 to be a good choice since it makes it far enough from the
4689 start of the data area as well as from the stack pointer.
4691 Please note that the environment is read-only until the monitor
4692 has been relocated to RAM and a RAM copy of the environment has been
4693 created; also, when using EEPROM you will have to use getenv_f()
4694 until then to read environment variables.
4696 The environment is protected by a CRC32 checksum. Before the monitor
4697 is relocated into RAM, as a result of a bad CRC you will be working
4698 with the compiled-in default environment - *silently*!!! [This is
4699 necessary, because the first environment variable we need is the
4700 "baudrate" setting for the console - if we have a bad CRC, we don't
4701 have any device yet where we could complain.]
4703 Note: once the monitor has been relocated, then it will complain if
4704 the default environment is used; a new CRC is computed as soon as you
4705 use the "saveenv" command to store a valid environment.
4707 - CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
4708 Echo the inverted Ethernet link state to the fault LED.
4710 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
4711 also needs to be defined.
4713 - CONFIG_SYS_FAULT_MII_ADDR:
4714 MII address of the PHY to check for the Ethernet link state.
4716 - CONFIG_NS16550_MIN_FUNCTIONS:
4717 Define this if you desire to only have use of the NS16550_init
4718 and NS16550_putc functions for the serial driver located at
4719 drivers/serial/ns16550.c. This option is useful for saving
4720 space for already greatly restricted images, including but not
4721 limited to NAND_SPL configurations.
4723 - CONFIG_DISPLAY_BOARDINFO
4724 Display information about the board that U-Boot is running on
4725 when U-Boot starts up. The board function checkboard() is called
4728 - CONFIG_DISPLAY_BOARDINFO_LATE
4729 Similar to the previous option, but display this information
4730 later, once stdio is running and output goes to the LCD, if
4733 - CONFIG_BOARD_SIZE_LIMIT:
4734 Maximum size of the U-Boot image. When defined, the
4735 build system checks that the actual size does not
4738 Low Level (hardware related) configuration options:
4739 ---------------------------------------------------
4741 - CONFIG_SYS_CACHELINE_SIZE:
4742 Cache Line Size of the CPU.
4744 - CONFIG_SYS_DEFAULT_IMMR:
4745 Default address of the IMMR after system reset.
4747 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
4748 and RPXsuper) to be able to adjust the position of
4749 the IMMR register after a reset.
4751 - CONFIG_SYS_CCSRBAR_DEFAULT:
4752 Default (power-on reset) physical address of CCSR on Freescale
4755 - CONFIG_SYS_CCSRBAR:
4756 Virtual address of CCSR. On a 32-bit build, this is typically
4757 the same value as CONFIG_SYS_CCSRBAR_DEFAULT.
4759 CONFIG_SYS_DEFAULT_IMMR must also be set to this value,
4760 for cross-platform code that uses that macro instead.
4762 - CONFIG_SYS_CCSRBAR_PHYS:
4763 Physical address of CCSR. CCSR can be relocated to a new
4764 physical address, if desired. In this case, this macro should
4765 be set to that address. Otherwise, it should be set to the
4766 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR
4767 is typically relocated on 36-bit builds. It is recommended
4768 that this macro be defined via the _HIGH and _LOW macros:
4770 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH
4771 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW)
4773 - CONFIG_SYS_CCSRBAR_PHYS_HIGH:
4774 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically
4775 either 0 (32-bit build) or 0xF (36-bit build). This macro is
4776 used in assembly code, so it must not contain typecasts or
4777 integer size suffixes (e.g. "ULL").
4779 - CONFIG_SYS_CCSRBAR_PHYS_LOW:
4780 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is
4781 used in assembly code, so it must not contain typecasts or
4782 integer size suffixes (e.g. "ULL").
4784 - CONFIG_SYS_CCSR_DO_NOT_RELOCATE:
4785 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be
4786 forced to a value that ensures that CCSR is not relocated.
4788 - Floppy Disk Support:
4789 CONFIG_SYS_FDC_DRIVE_NUMBER
4791 the default drive number (default value 0)
4793 CONFIG_SYS_ISA_IO_STRIDE
4795 defines the spacing between FDC chipset registers
4798 CONFIG_SYS_ISA_IO_OFFSET
4800 defines the offset of register from address. It
4801 depends on which part of the data bus is connected to
4802 the FDC chipset. (default value 0)
4804 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
4805 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
4808 if CONFIG_SYS_FDC_HW_INIT is defined, then the function
4809 fdc_hw_init() is called at the beginning of the FDC
4810 setup. fdc_hw_init() must be provided by the board
4811 source code. It is used to make hardware-dependent
4815 Most IDE controllers were designed to be connected with PCI
4816 interface. Only few of them were designed for AHB interface.
4817 When software is doing ATA command and data transfer to
4818 IDE devices through IDE-AHB controller, some additional
4819 registers accessing to these kind of IDE-AHB controller
4822 - CONFIG_SYS_IMMR: Physical address of the Internal Memory.
4823 DO NOT CHANGE unless you know exactly what you're
4824 doing! (11-4) [MPC8xx/82xx systems only]
4826 - CONFIG_SYS_INIT_RAM_ADDR:
4828 Start address of memory area that can be used for
4829 initial data and stack; please note that this must be
4830 writable memory that is working WITHOUT special
4831 initialization, i. e. you CANNOT use normal RAM which
4832 will become available only after programming the
4833 memory controller and running certain initialization
4836 U-Boot uses the following memory types:
4837 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
4838 - MPC824X: data cache
4839 - PPC4xx: data cache
4841 - CONFIG_SYS_GBL_DATA_OFFSET:
4843 Offset of the initial data structure in the memory
4844 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
4845 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
4846 data is located at the end of the available space
4847 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
4848 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just
4849 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
4850 CONFIG_SYS_GBL_DATA_OFFSET) downward.
4853 On the MPC824X (or other systems that use the data
4854 cache for initial memory) the address chosen for
4855 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
4856 point to an otherwise UNUSED address space between
4857 the top of RAM and the start of the PCI space.
4859 - CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6)
4861 - CONFIG_SYS_SYPCR: System Protection Control (11-9)
4863 - CONFIG_SYS_TBSCR: Time Base Status and Control (11-26)
4865 - CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31)
4867 - CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
4869 - CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
4871 - CONFIG_SYS_OR_TIMING_SDRAM:
4874 - CONFIG_SYS_MAMR_PTA:
4875 periodic timer for refresh
4877 - CONFIG_SYS_DER: Debug Event Register (37-47)
4879 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
4880 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
4881 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
4882 CONFIG_SYS_BR1_PRELIM:
4883 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
4885 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
4886 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
4887 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
4888 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
4890 - CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K,
4891 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL:
4892 Machine Mode Register and Memory Periodic Timer
4893 Prescaler definitions (SDRAM timing)
4895 - CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]:
4896 enable I2C microcode relocation patch (MPC8xx);
4897 define relocation offset in DPRAM [DSP2]
4899 - CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]:
4900 enable SMC microcode relocation patch (MPC8xx);
4901 define relocation offset in DPRAM [SMC1]
4903 - CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]:
4904 enable SPI microcode relocation patch (MPC8xx);
4905 define relocation offset in DPRAM [SCC4]
4907 - CONFIG_SYS_USE_OSCCLK:
4908 Use OSCM clock mode on MBX8xx board. Be careful,
4909 wrong setting might damage your board. Read
4910 doc/README.MBX before setting this variable!
4912 - CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
4913 Offset of the bootmode word in DPRAM used by post
4914 (Power On Self Tests). This definition overrides
4915 #define'd default value in commproc.h resp.
4918 - CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB,
4919 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL,
4920 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS,
4921 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB,
4922 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
4923 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL,
4924 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE,
4925 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only)
4926 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set.
4928 - CONFIG_PCI_DISABLE_PCIE:
4929 Disable PCI-Express on systems where it is supported but not
4932 - CONFIG_PCI_ENUM_ONLY
4933 Only scan through and get the devices on the buses.
4934 Don't do any setup work, presumably because someone or
4935 something has already done it, and we don't need to do it
4936 a second time. Useful for platforms that are pre-booted
4937 by coreboot or similar.
4939 - CONFIG_PCI_INDIRECT_BRIDGE:
4940 Enable support for indirect PCI bridges.
4943 Chip has SRIO or not
4946 Board has SRIO 1 port available
4949 Board has SRIO 2 port available
4951 - CONFIG_SRIO_PCIE_BOOT_MASTER
4952 Board can support master function for Boot from SRIO and PCIE
4954 - CONFIG_SYS_SRIOn_MEM_VIRT:
4955 Virtual Address of SRIO port 'n' memory region
4957 - CONFIG_SYS_SRIOn_MEM_PHYS:
4958 Physical Address of SRIO port 'n' memory region
4960 - CONFIG_SYS_SRIOn_MEM_SIZE:
4961 Size of SRIO port 'n' memory region
4963 - CONFIG_SYS_NAND_BUSWIDTH_16BIT
4964 Defined to tell the NAND controller that the NAND chip is using
4966 Not all NAND drivers use this symbol.
4967 Example of drivers that use it:
4968 - drivers/mtd/nand/ndfc.c
4969 - drivers/mtd/nand/mxc_nand.c
4971 - CONFIG_SYS_NDFC_EBC0_CFG
4972 Sets the EBC0_CFG register for the NDFC. If not defined
4973 a default value will be used.
4976 Get DDR timing information from an I2C EEPROM. Common
4977 with pluggable memory modules such as SODIMMs
4980 I2C address of the SPD EEPROM
4982 - CONFIG_SYS_SPD_BUS_NUM
4983 If SPD EEPROM is on an I2C bus other than the first
4984 one, specify here. Note that the value must resolve
4985 to something your driver can deal with.
4987 - CONFIG_SYS_DDR_RAW_TIMING
4988 Get DDR timing information from other than SPD. Common with
4989 soldered DDR chips onboard without SPD. DDR raw timing
4990 parameters are extracted from datasheet and hard-coded into
4991 header files or board specific files.
4993 - CONFIG_FSL_DDR_INTERACTIVE
4994 Enable interactive DDR debugging. See doc/README.fsl-ddr.
4996 - CONFIG_FSL_DDR_SYNC_REFRESH
4997 Enable sync of refresh for multiple controllers.
4999 - CONFIG_FSL_DDR_BIST
5000 Enable built-in memory test for Freescale DDR controllers.
5002 - CONFIG_SYS_83XX_DDR_USES_CS0
5003 Only for 83xx systems. If specified, then DDR should
5004 be configured using CS0 and CS1 instead of CS2 and CS3.
5006 - CONFIG_ETHER_ON_FEC[12]
5007 Define to enable FEC[12] on a 8xx series processor.
5009 - CONFIG_FEC[12]_PHY
5010 Define to the hardcoded PHY address which corresponds
5011 to the given FEC; i. e.
5012 #define CONFIG_FEC1_PHY 4
5013 means that the PHY with address 4 is connected to FEC1
5015 When set to -1, means to probe for first available.
5017 - CONFIG_FEC[12]_PHY_NORXERR
5018 The PHY does not have a RXERR line (RMII only).
5019 (so program the FEC to ignore it).
5022 Enable RMII mode for all FECs.
5023 Note that this is a global option, we can't
5024 have one FEC in standard MII mode and another in RMII mode.
5026 - CONFIG_CRC32_VERIFY
5027 Add a verify option to the crc32 command.
5030 => crc32 -v <address> <count> <crc32>
5032 Where address/count indicate a memory area
5033 and crc32 is the correct crc32 which the
5037 Add the "loopw" memory command. This only takes effect if
5038 the memory commands are activated globally (CONFIG_CMD_MEM).
5041 Add the "mdc" and "mwc" memory commands. These are cyclic
5046 This command will print 4 bytes (10,11,12,13) each 500 ms.
5048 => mwc.l 100 12345678 10
5049 This command will write 12345678 to address 100 all 10 ms.
5051 This only takes effect if the memory commands are activated
5052 globally (CONFIG_CMD_MEM).
5054 - CONFIG_SKIP_LOWLEVEL_INIT
5055 [ARM, NDS32, MIPS only] If this variable is defined, then certain
5056 low level initializations (like setting up the memory
5057 controller) are omitted and/or U-Boot does not
5058 relocate itself into RAM.
5060 Normally this variable MUST NOT be defined. The only
5061 exception is when U-Boot is loaded (to RAM) by some
5062 other boot loader or by a debugger which performs
5063 these initializations itself.
5066 Modifies the behaviour of start.S when compiling a loader
5067 that is executed before the actual U-Boot. E.g. when
5068 compiling a NAND SPL.
5071 Modifies the behaviour of start.S when compiling a loader
5072 that is executed after the SPL and before the actual U-Boot.
5073 It is loaded by the SPL.
5075 - CONFIG_SYS_MPC85XX_NO_RESETVEC
5076 Only for 85xx systems. If this variable is specified, the section
5077 .resetvec is not kept and the section .bootpg is placed in the
5078 previous 4k of the .text section.
5080 - CONFIG_ARCH_MAP_SYSMEM
5081 Generally U-Boot (and in particular the md command) uses
5082 effective address. It is therefore not necessary to regard
5083 U-Boot address as virtual addresses that need to be translated
5084 to physical addresses. However, sandbox requires this, since
5085 it maintains its own little RAM buffer which contains all
5086 addressable memory. This option causes some memory accesses
5087 to be mapped through map_sysmem() / unmap_sysmem().
5089 - CONFIG_USE_ARCH_MEMCPY
5090 CONFIG_USE_ARCH_MEMSET
5091 If these options are used a optimized version of memcpy/memset will
5092 be used if available. These functions may be faster under some
5093 conditions but may increase the binary size.
5095 - CONFIG_X86_RESET_VECTOR
5096 If defined, the x86 reset vector code is included. This is not
5097 needed when U-Boot is running from Coreboot.
5100 Defines the MPU clock speed (in MHz).
5102 NOTE : currently only supported on AM335x platforms.
5104 - CONFIG_SPL_AM33XX_ENABLE_RTC32K_OSC:
5105 Enables the RTC32K OSC on AM33xx based plattforms
5107 - CONFIG_SYS_NAND_NO_SUBPAGE_WRITE
5108 Option to disable subpage write in NAND driver
5109 driver that uses this:
5110 drivers/mtd/nand/davinci_nand.c
5112 Freescale QE/FMAN Firmware Support:
5113 -----------------------------------
5115 The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
5116 loading of "firmware", which is encoded in the QE firmware binary format.
5117 This firmware often needs to be loaded during U-Boot booting, so macros
5118 are used to identify the storage device (NOR flash, SPI, etc) and the address
5121 - CONFIG_SYS_FMAN_FW_ADDR
5122 The address in the storage device where the FMAN microcode is located. The
5123 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
5126 - CONFIG_SYS_QE_FW_ADDR
5127 The address in the storage device where the QE microcode is located. The
5128 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
5131 - CONFIG_SYS_QE_FMAN_FW_LENGTH
5132 The maximum possible size of the firmware. The firmware binary format
5133 has a field that specifies the actual size of the firmware, but it
5134 might not be possible to read any part of the firmware unless some
5135 local storage is allocated to hold the entire firmware first.
5137 - CONFIG_SYS_QE_FMAN_FW_IN_NOR
5138 Specifies that QE/FMAN firmware is located in NOR flash, mapped as
5139 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the
5140 virtual address in NOR flash.
5142 - CONFIG_SYS_QE_FMAN_FW_IN_NAND
5143 Specifies that QE/FMAN firmware is located in NAND flash.
5144 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.
5146 - CONFIG_SYS_QE_FMAN_FW_IN_MMC
5147 Specifies that QE/FMAN firmware is located on the primary SD/MMC
5148 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
5150 - CONFIG_SYS_QE_FMAN_FW_IN_SPIFLASH
5151 Specifies that QE/FMAN firmware is located on the primary SPI
5152 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
5154 - CONFIG_SYS_QE_FMAN_FW_IN_REMOTE
5155 Specifies that QE/FMAN firmware is located in the remote (master)
5156 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which
5157 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound
5158 window->master inbound window->master LAW->the ucode address in
5159 master's memory space.
5161 Freescale Layerscape Management Complex Firmware Support:
5162 ---------------------------------------------------------
5163 The Freescale Layerscape Management Complex (MC) supports the loading of
5165 This firmware often needs to be loaded during U-Boot booting, so macros
5166 are used to identify the storage device (NOR flash, SPI, etc) and the address
5169 - CONFIG_FSL_MC_ENET
5170 Enable the MC driver for Layerscape SoCs.
5172 - CONFIG_SYS_LS_MC_FW_ADDR
5173 The address in the storage device where the firmware is located. The
5174 meaning of this address depends on which CONFIG_SYS_LS_MC_FW_IN_xxx macro
5177 - CONFIG_SYS_LS_MC_FW_LENGTH
5178 The maximum possible size of the firmware. The firmware binary format
5179 has a field that specifies the actual size of the firmware, but it
5180 might not be possible to read any part of the firmware unless some
5181 local storage is allocated to hold the entire firmware first.
5183 - CONFIG_SYS_LS_MC_FW_IN_NOR
5184 Specifies that MC firmware is located in NOR flash, mapped as
5185 normal addressable memory via the LBC. CONFIG_SYS_LS_MC_FW_ADDR is the
5186 virtual address in NOR flash.
5188 Freescale Layerscape Debug Server Support:
5189 -------------------------------------------
5190 The Freescale Layerscape Debug Server Support supports the loading of
5191 "Debug Server firmware" and triggering SP boot-rom.
5192 This firmware often needs to be loaded during U-Boot booting.
5194 - CONFIG_FSL_DEBUG_SERVER
5195 Enable the Debug Server for Layerscape SoCs.
5197 - CONFIG_SYS_DEBUG_SERVER_DRAM_BLOCK_MIN_SIZE
5198 Define minimum DDR size required for debug server image
5200 - CONFIG_SYS_MEM_TOP_HIDE_MIN
5201 Define minimum DDR size to be hided from top of the DDR memory
5206 In order to achieve reproducible builds, timestamps used in the U-Boot build
5207 process have to be set to a fixed value.
5209 This is done using the SOURCE_DATE_EPOCH environment variable.
5210 SOURCE_DATE_EPOCH is to be set on the build host's shell, not as a configuration
5211 option for U-Boot or an environment variable in U-Boot.
5213 SOURCE_DATE_EPOCH should be set to a number of seconds since the epoch, in UTC.
5215 Building the Software:
5216 ======================
5218 Building U-Boot has been tested in several native build environments
5219 and in many different cross environments. Of course we cannot support
5220 all possibly existing versions of cross development tools in all
5221 (potentially obsolete) versions. In case of tool chain problems we
5222 recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
5223 which is extensively used to build and test U-Boot.
5225 If you are not using a native environment, it is assumed that you
5226 have GNU cross compiling tools available in your path. In this case,
5227 you must set the environment variable CROSS_COMPILE in your shell.
5228 Note that no changes to the Makefile or any other source files are
5229 necessary. For example using the ELDK on a 4xx CPU, please enter:
5231 $ CROSS_COMPILE=ppc_4xx-
5232 $ export CROSS_COMPILE
5234 Note: If you wish to generate Windows versions of the utilities in
5235 the tools directory you can use the MinGW toolchain
5236 (http://www.mingw.org). Set your HOST tools to the MinGW
5237 toolchain and execute 'make tools'. For example:
5239 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
5241 Binaries such as tools/mkimage.exe will be created which can
5242 be executed on computers running Windows.
5244 U-Boot is intended to be simple to build. After installing the
5245 sources you must configure U-Boot for one specific board type. This
5250 where "NAME_defconfig" is the name of one of the existing configu-
5251 rations; see boards.cfg for supported names.
5253 Note: for some board special configuration names may exist; check if
5254 additional information is available from the board vendor; for
5255 instance, the TQM823L systems are available without (standard)
5256 or with LCD support. You can select such additional "features"
5257 when choosing the configuration, i. e.
5259 make TQM823L_defconfig
5260 - will configure for a plain TQM823L, i. e. no LCD support
5262 make TQM823L_LCD_defconfig
5263 - will configure for a TQM823L with U-Boot console on LCD
5268 Finally, type "make all", and you should get some working U-Boot
5269 images ready for download to / installation on your system:
5271 - "u-boot.bin" is a raw binary image
5272 - "u-boot" is an image in ELF binary format
5273 - "u-boot.srec" is in Motorola S-Record format
5275 By default the build is performed locally and the objects are saved
5276 in the source directory. One of the two methods can be used to change
5277 this behavior and build U-Boot to some external directory:
5279 1. Add O= to the make command line invocations:
5281 make O=/tmp/build distclean
5282 make O=/tmp/build NAME_defconfig
5283 make O=/tmp/build all
5285 2. Set environment variable KBUILD_OUTPUT to point to the desired location:
5287 export KBUILD_OUTPUT=/tmp/build
5292 Note that the command line "O=" setting overrides the KBUILD_OUTPUT environment
5296 Please be aware that the Makefiles assume you are using GNU make, so
5297 for instance on NetBSD you might need to use "gmake" instead of
5301 If the system board that you have is not listed, then you will need
5302 to port U-Boot to your hardware platform. To do this, follow these
5305 1. Add a new configuration option for your board to the toplevel
5306 "boards.cfg" file, using the existing entries as examples.
5307 Follow the instructions there to keep the boards in order.
5308 2. Create a new directory to hold your board specific code. Add any
5309 files you need. In your board directory, you will need at least
5310 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
5311 3. Create a new configuration file "include/configs/<board>.h" for
5313 3. If you're porting U-Boot to a new CPU, then also create a new
5314 directory to hold your CPU specific code. Add any files you need.
5315 4. Run "make <board>_defconfig" with your new name.
5316 5. Type "make", and you should get a working "u-boot.srec" file
5317 to be installed on your target system.
5318 6. Debug and solve any problems that might arise.
5319 [Of course, this last step is much harder than it sounds.]
5322 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
5323 ==============================================================
5325 If you have modified U-Boot sources (for instance added a new board
5326 or support for new devices, a new CPU, etc.) you are expected to
5327 provide feedback to the other developers. The feedback normally takes
5328 the form of a "patch", i. e. a context diff against a certain (latest
5329 official or latest in the git repository) version of U-Boot sources.
5331 But before you submit such a patch, please verify that your modifi-
5332 cation did not break existing code. At least make sure that *ALL* of
5333 the supported boards compile WITHOUT ANY compiler warnings. To do so,
5334 just run the "MAKEALL" script, which will configure and build U-Boot
5335 for ALL supported system. Be warned, this will take a while. You can
5336 select which (cross) compiler to use by passing a `CROSS_COMPILE'
5337 environment variable to the script, i. e. to use the ELDK cross tools
5340 CROSS_COMPILE=ppc_8xx- MAKEALL
5342 or to build on a native PowerPC system you can type
5344 CROSS_COMPILE=' ' MAKEALL
5346 When using the MAKEALL script, the default behaviour is to build
5347 U-Boot in the source directory. This location can be changed by
5348 setting the BUILD_DIR environment variable. Also, for each target
5349 built, the MAKEALL script saves two log files (<target>.ERR and
5350 <target>.MAKEALL) in the <source dir>/LOG directory. This default
5351 location can be changed by setting the MAKEALL_LOGDIR environment
5352 variable. For example:
5354 export BUILD_DIR=/tmp/build
5355 export MAKEALL_LOGDIR=/tmp/log
5356 CROSS_COMPILE=ppc_8xx- MAKEALL
5358 With the above settings build objects are saved in the /tmp/build,
5359 log files are saved in the /tmp/log and the source tree remains clean
5360 during the whole build process.
5363 See also "U-Boot Porting Guide" below.
5366 Monitor Commands - Overview:
5367 ============================
5369 go - start application at address 'addr'
5370 run - run commands in an environment variable
5371 bootm - boot application image from memory
5372 bootp - boot image via network using BootP/TFTP protocol
5373 bootz - boot zImage from memory
5374 tftpboot- boot image via network using TFTP protocol
5375 and env variables "ipaddr" and "serverip"
5376 (and eventually "gatewayip")
5377 tftpput - upload a file via network using TFTP protocol
5378 rarpboot- boot image via network using RARP/TFTP protocol
5379 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
5380 loads - load S-Record file over serial line
5381 loadb - load binary file over serial line (kermit mode)
5383 mm - memory modify (auto-incrementing)
5384 nm - memory modify (constant address)
5385 mw - memory write (fill)
5387 cmp - memory compare
5388 crc32 - checksum calculation
5389 i2c - I2C sub-system
5390 sspi - SPI utility commands
5391 base - print or set address offset
5392 printenv- print environment variables
5393 setenv - set environment variables
5394 saveenv - save environment variables to persistent storage
5395 protect - enable or disable FLASH write protection
5396 erase - erase FLASH memory
5397 flinfo - print FLASH memory information
5398 nand - NAND memory operations (see doc/README.nand)
5399 bdinfo - print Board Info structure
5400 iminfo - print header information for application image
5401 coninfo - print console devices and informations
5402 ide - IDE sub-system
5403 loop - infinite loop on address range
5404 loopw - infinite write loop on address range
5405 mtest - simple RAM test
5406 icache - enable or disable instruction cache
5407 dcache - enable or disable data cache
5408 reset - Perform RESET of the CPU
5409 echo - echo args to console
5410 version - print monitor version
5411 help - print online help
5412 ? - alias for 'help'
5415 Monitor Commands - Detailed Description:
5416 ========================================
5420 For now: just type "help <command>".
5423 Environment Variables:
5424 ======================
5426 U-Boot supports user configuration using Environment Variables which
5427 can be made persistent by saving to Flash memory.
5429 Environment Variables are set using "setenv", printed using
5430 "printenv", and saved to Flash using "saveenv". Using "setenv"
5431 without a value can be used to delete a variable from the
5432 environment. As long as you don't save the environment you are
5433 working with an in-memory copy. In case the Flash area containing the
5434 environment is erased by accident, a default environment is provided.
5436 Some configuration options can be set using Environment Variables.
5438 List of environment variables (most likely not complete):
5440 baudrate - see CONFIG_BAUDRATE
5442 bootdelay - see CONFIG_BOOTDELAY
5444 bootcmd - see CONFIG_BOOTCOMMAND
5446 bootargs - Boot arguments when booting an RTOS image
5448 bootfile - Name of the image to load with TFTP
5450 bootm_low - Memory range available for image processing in the bootm
5451 command can be restricted. This variable is given as
5452 a hexadecimal number and defines lowest address allowed
5453 for use by the bootm command. See also "bootm_size"
5454 environment variable. Address defined by "bootm_low" is
5455 also the base of the initial memory mapping for the Linux
5456 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
5459 bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
5460 This variable is given as a hexadecimal number and it
5461 defines the size of the memory region starting at base
5462 address bootm_low that is accessible by the Linux kernel
5463 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used
5464 as the default value if it is defined, and bootm_size is
5467 bootm_size - Memory range available for image processing in the bootm
5468 command can be restricted. This variable is given as
5469 a hexadecimal number and defines the size of the region
5470 allowed for use by the bootm command. See also "bootm_low"
5471 environment variable.
5473 updatefile - Location of the software update file on a TFTP server, used
5474 by the automatic software update feature. Please refer to
5475 documentation in doc/README.update for more details.
5477 autoload - if set to "no" (any string beginning with 'n'),
5478 "bootp" will just load perform a lookup of the
5479 configuration from the BOOTP server, but not try to
5480 load any image using TFTP
5482 autostart - if set to "yes", an image loaded using the "bootp",
5483 "rarpboot", "tftpboot" or "diskboot" commands will
5484 be automatically started (by internally calling
5487 If set to "no", a standalone image passed to the
5488 "bootm" command will be copied to the load address
5489 (and eventually uncompressed), but NOT be started.
5490 This can be used to load and uncompress arbitrary
5493 fdt_high - if set this restricts the maximum address that the
5494 flattened device tree will be copied into upon boot.
5495 For example, if you have a system with 1 GB memory
5496 at physical address 0x10000000, while Linux kernel
5497 only recognizes the first 704 MB as low memory, you
5498 may need to set fdt_high as 0x3C000000 to have the
5499 device tree blob be copied to the maximum address
5500 of the 704 MB low memory, so that Linux kernel can
5501 access it during the boot procedure.
5503 If this is set to the special value 0xFFFFFFFF then
5504 the fdt will not be copied at all on boot. For this
5505 to work it must reside in writable memory, have
5506 sufficient padding on the end of it for u-boot to
5507 add the information it needs into it, and the memory
5508 must be accessible by the kernel.
5510 fdtcontroladdr- if set this is the address of the control flattened
5511 device tree used by U-Boot when CONFIG_OF_CONTROL is
5514 i2cfast - (PPC405GP|PPC405EP only)
5515 if set to 'y' configures Linux I2C driver for fast
5516 mode (400kHZ). This environment variable is used in
5517 initialization code. So, for changes to be effective
5518 it must be saved and board must be reset.
5520 initrd_high - restrict positioning of initrd images:
5521 If this variable is not set, initrd images will be
5522 copied to the highest possible address in RAM; this
5523 is usually what you want since it allows for
5524 maximum initrd size. If for some reason you want to
5525 make sure that the initrd image is loaded below the
5526 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
5527 variable to a value of "no" or "off" or "0".
5528 Alternatively, you can set it to a maximum upper
5529 address to use (U-Boot will still check that it
5530 does not overwrite the U-Boot stack and data).
5532 For instance, when you have a system with 16 MB
5533 RAM, and want to reserve 4 MB from use by Linux,
5534 you can do this by adding "mem=12M" to the value of
5535 the "bootargs" variable. However, now you must make
5536 sure that the initrd image is placed in the first
5537 12 MB as well - this can be done with
5539 setenv initrd_high 00c00000
5541 If you set initrd_high to 0xFFFFFFFF, this is an
5542 indication to U-Boot that all addresses are legal
5543 for the Linux kernel, including addresses in flash
5544 memory. In this case U-Boot will NOT COPY the
5545 ramdisk at all. This may be useful to reduce the
5546 boot time on your system, but requires that this
5547 feature is supported by your Linux kernel.
5549 ipaddr - IP address; needed for tftpboot command
5551 loadaddr - Default load address for commands like "bootp",
5552 "rarpboot", "tftpboot", "loadb" or "diskboot"
5554 loads_echo - see CONFIG_LOADS_ECHO
5556 serverip - TFTP server IP address; needed for tftpboot command
5558 bootretry - see CONFIG_BOOT_RETRY_TIME
5560 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
5562 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
5564 ethprime - controls which interface is used first.
5566 ethact - controls which interface is currently active.
5567 For example you can do the following
5569 => setenv ethact FEC
5570 => ping 192.168.0.1 # traffic sent on FEC
5571 => setenv ethact SCC
5572 => ping 10.0.0.1 # traffic sent on SCC
5574 ethrotate - When set to "no" U-Boot does not go through all
5575 available network interfaces.
5576 It just stays at the currently selected interface.
5578 netretry - When set to "no" each network operation will
5579 either succeed or fail without retrying.
5580 When set to "once" the network operation will
5581 fail when all the available network interfaces
5582 are tried once without success.
5583 Useful on scripts which control the retry operation
5586 npe_ucode - set load address for the NPE microcode
5588 silent_linux - If set then Linux will be told to boot silently, by
5589 changing the console to be empty. If "yes" it will be
5590 made silent. If "no" it will not be made silent. If
5591 unset, then it will be made silent if the U-Boot console
5594 tftpsrcport - If this is set, the value is used for TFTP's
5597 tftpdstport - If this is set, the value is used for TFTP's UDP
5598 destination port instead of the Well Know Port 69.
5600 tftpblocksize - Block size to use for TFTP transfers; if not set,
5601 we use the TFTP server's default block size
5603 tftptimeout - Retransmission timeout for TFTP packets (in milli-
5604 seconds, minimum value is 1000 = 1 second). Defines
5605 when a packet is considered to be lost so it has to
5606 be retransmitted. The default is 5000 = 5 seconds.
5607 Lowering this value may make downloads succeed
5608 faster in networks with high packet loss rates or
5609 with unreliable TFTP servers.
5611 vlan - When set to a value < 4095 the traffic over
5612 Ethernet is encapsulated/received over 802.1q
5615 The following image location variables contain the location of images
5616 used in booting. The "Image" column gives the role of the image and is
5617 not an environment variable name. The other columns are environment
5618 variable names. "File Name" gives the name of the file on a TFTP
5619 server, "RAM Address" gives the location in RAM the image will be
5620 loaded to, and "Flash Location" gives the image's address in NOR
5621 flash or offset in NAND flash.
5623 *Note* - these variables don't have to be defined for all boards, some
5624 boards currently use other variables for these purposes, and some
5625 boards use these variables for other purposes.
5627 Image File Name RAM Address Flash Location
5628 ----- --------- ----------- --------------
5629 u-boot u-boot u-boot_addr_r u-boot_addr
5630 Linux kernel bootfile kernel_addr_r kernel_addr
5631 device tree blob fdtfile fdt_addr_r fdt_addr
5632 ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr
5634 The following environment variables may be used and automatically
5635 updated by the network boot commands ("bootp" and "rarpboot"),
5636 depending the information provided by your boot server:
5638 bootfile - see above
5639 dnsip - IP address of your Domain Name Server
5640 dnsip2 - IP address of your secondary Domain Name Server
5641 gatewayip - IP address of the Gateway (Router) to use
5642 hostname - Target hostname
5644 netmask - Subnet Mask
5645 rootpath - Pathname of the root filesystem on the NFS server
5646 serverip - see above
5649 There are two special Environment Variables:
5651 serial# - contains hardware identification information such
5652 as type string and/or serial number
5653 ethaddr - Ethernet address
5655 These variables can be set only once (usually during manufacturing of
5656 the board). U-Boot refuses to delete or overwrite these variables
5657 once they have been set once.
5660 Further special Environment Variables:
5662 ver - Contains the U-Boot version string as printed
5663 with the "version" command. This variable is
5664 readonly (see CONFIG_VERSION_VARIABLE).
5667 Please note that changes to some configuration parameters may take
5668 only effect after the next boot (yes, that's just like Windoze :-).
5671 Callback functions for environment variables:
5672 ---------------------------------------------
5674 For some environment variables, the behavior of u-boot needs to change
5675 when their values are changed. This functionality allows functions to
5676 be associated with arbitrary variables. On creation, overwrite, or
5677 deletion, the callback will provide the opportunity for some side
5678 effect to happen or for the change to be rejected.
5680 The callbacks are named and associated with a function using the
5681 U_BOOT_ENV_CALLBACK macro in your board or driver code.
5683 These callbacks are associated with variables in one of two ways. The
5684 static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC
5685 in the board configuration to a string that defines a list of
5686 associations. The list must be in the following format:
5688 entry = variable_name[:callback_name]
5691 If the callback name is not specified, then the callback is deleted.
5692 Spaces are also allowed anywhere in the list.
5694 Callbacks can also be associated by defining the ".callbacks" variable
5695 with the same list format above. Any association in ".callbacks" will
5696 override any association in the static list. You can define
5697 CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the
5698 ".callbacks" environment variable in the default or embedded environment.
5700 If CONFIG_REGEX is defined, the variable_name above is evaluated as a
5701 regular expression. This allows multiple variables to be connected to
5702 the same callback without explicitly listing them all out.
5705 Command Line Parsing:
5706 =====================
5708 There are two different command line parsers available with U-Boot:
5709 the old "simple" one, and the much more powerful "hush" shell:
5711 Old, simple command line parser:
5712 --------------------------------
5714 - supports environment variables (through setenv / saveenv commands)
5715 - several commands on one line, separated by ';'
5716 - variable substitution using "... ${name} ..." syntax
5717 - special characters ('$', ';') can be escaped by prefixing with '\',
5719 setenv bootcmd bootm \${address}
5720 - You can also escape text by enclosing in single apostrophes, for example:
5721 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
5726 - similar to Bourne shell, with control structures like
5727 if...then...else...fi, for...do...done; while...do...done,
5728 until...do...done, ...
5729 - supports environment ("global") variables (through setenv / saveenv
5730 commands) and local shell variables (through standard shell syntax
5731 "name=value"); only environment variables can be used with "run"
5737 (1) If a command line (or an environment variable executed by a "run"
5738 command) contains several commands separated by semicolon, and
5739 one of these commands fails, then the remaining commands will be
5742 (2) If you execute several variables with one call to run (i. e.
5743 calling run with a list of variables as arguments), any failing
5744 command will cause "run" to terminate, i. e. the remaining
5745 variables are not executed.
5747 Note for Redundant Ethernet Interfaces:
5748 =======================================
5750 Some boards come with redundant Ethernet interfaces; U-Boot supports
5751 such configurations and is capable of automatic selection of a
5752 "working" interface when needed. MAC assignment works as follows:
5754 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
5755 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
5756 "eth1addr" (=>eth1), "eth2addr", ...
5758 If the network interface stores some valid MAC address (for instance
5759 in SROM), this is used as default address if there is NO correspon-
5760 ding setting in the environment; if the corresponding environment
5761 variable is set, this overrides the settings in the card; that means:
5763 o If the SROM has a valid MAC address, and there is no address in the
5764 environment, the SROM's address is used.
5766 o If there is no valid address in the SROM, and a definition in the
5767 environment exists, then the value from the environment variable is
5770 o If both the SROM and the environment contain a MAC address, and
5771 both addresses are the same, this MAC address is used.
5773 o If both the SROM and the environment contain a MAC address, and the
5774 addresses differ, the value from the environment is used and a
5777 o If neither SROM nor the environment contain a MAC address, an error
5778 is raised. If CONFIG_NET_RANDOM_ETHADDR is defined, then in this case
5779 a random, locally-assigned MAC is used.
5781 If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
5782 will be programmed into hardware as part of the initialization process. This
5783 may be skipped by setting the appropriate 'ethmacskip' environment variable.
5784 The naming convention is as follows:
5785 "ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
5790 U-Boot is capable of booting (and performing other auxiliary operations on)
5791 images in two formats:
5793 New uImage format (FIT)
5794 -----------------------
5796 Flexible and powerful format based on Flattened Image Tree -- FIT (similar
5797 to Flattened Device Tree). It allows the use of images with multiple
5798 components (several kernels, ramdisks, etc.), with contents protected by
5799 SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
5805 Old image format is based on binary files which can be basically anything,
5806 preceded by a special header; see the definitions in include/image.h for
5807 details; basically, the header defines the following image properties:
5809 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
5810 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
5811 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
5812 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
5814 * Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86,
5815 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
5816 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC).
5817 * Compression Type (uncompressed, gzip, bzip2)
5823 The header is marked by a special Magic Number, and both the header
5824 and the data portions of the image are secured against corruption by
5831 Although U-Boot should support any OS or standalone application
5832 easily, the main focus has always been on Linux during the design of
5835 U-Boot includes many features that so far have been part of some
5836 special "boot loader" code within the Linux kernel. Also, any
5837 "initrd" images to be used are no longer part of one big Linux image;
5838 instead, kernel and "initrd" are separate images. This implementation
5839 serves several purposes:
5841 - the same features can be used for other OS or standalone
5842 applications (for instance: using compressed images to reduce the
5843 Flash memory footprint)
5845 - it becomes much easier to port new Linux kernel versions because
5846 lots of low-level, hardware dependent stuff are done by U-Boot
5848 - the same Linux kernel image can now be used with different "initrd"
5849 images; of course this also means that different kernel images can
5850 be run with the same "initrd". This makes testing easier (you don't
5851 have to build a new "zImage.initrd" Linux image when you just
5852 change a file in your "initrd"). Also, a field-upgrade of the
5853 software is easier now.
5859 Porting Linux to U-Boot based systems:
5860 ---------------------------------------
5862 U-Boot cannot save you from doing all the necessary modifications to
5863 configure the Linux device drivers for use with your target hardware
5864 (no, we don't intend to provide a full virtual machine interface to
5867 But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
5869 Just make sure your machine specific header file (for instance
5870 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
5871 Information structure as we define in include/asm-<arch>/u-boot.h,
5872 and make sure that your definition of IMAP_ADDR uses the same value
5873 as your U-Boot configuration in CONFIG_SYS_IMMR.
5875 Note that U-Boot now has a driver model, a unified model for drivers.
5876 If you are adding a new driver, plumb it into driver model. If there
5877 is no uclass available, you are encouraged to create one. See
5881 Configuring the Linux kernel:
5882 -----------------------------
5884 No specific requirements for U-Boot. Make sure you have some root
5885 device (initial ramdisk, NFS) for your target system.
5888 Building a Linux Image:
5889 -----------------------
5891 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
5892 not used. If you use recent kernel source, a new build target
5893 "uImage" will exist which automatically builds an image usable by
5894 U-Boot. Most older kernels also have support for a "pImage" target,
5895 which was introduced for our predecessor project PPCBoot and uses a
5896 100% compatible format.
5900 make TQM850L_defconfig
5905 The "uImage" build target uses a special tool (in 'tools/mkimage') to
5906 encapsulate a compressed Linux kernel image with header information,
5907 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
5909 * build a standard "vmlinux" kernel image (in ELF binary format):
5911 * convert the kernel into a raw binary image:
5913 ${CROSS_COMPILE}-objcopy -O binary \
5914 -R .note -R .comment \
5915 -S vmlinux linux.bin
5917 * compress the binary image:
5921 * package compressed binary image for U-Boot:
5923 mkimage -A ppc -O linux -T kernel -C gzip \
5924 -a 0 -e 0 -n "Linux Kernel Image" \
5925 -d linux.bin.gz uImage
5928 The "mkimage" tool can also be used to create ramdisk images for use
5929 with U-Boot, either separated from the Linux kernel image, or
5930 combined into one file. "mkimage" encapsulates the images with a 64
5931 byte header containing information about target architecture,
5932 operating system, image type, compression method, entry points, time
5933 stamp, CRC32 checksums, etc.
5935 "mkimage" can be called in two ways: to verify existing images and
5936 print the header information, or to build new images.
5938 In the first form (with "-l" option) mkimage lists the information
5939 contained in the header of an existing U-Boot image; this includes
5940 checksum verification:
5942 tools/mkimage -l image
5943 -l ==> list image header information
5945 The second form (with "-d" option) is used to build a U-Boot image
5946 from a "data file" which is used as image payload:
5948 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
5949 -n name -d data_file image
5950 -A ==> set architecture to 'arch'
5951 -O ==> set operating system to 'os'
5952 -T ==> set image type to 'type'
5953 -C ==> set compression type 'comp'
5954 -a ==> set load address to 'addr' (hex)
5955 -e ==> set entry point to 'ep' (hex)
5956 -n ==> set image name to 'name'
5957 -d ==> use image data from 'datafile'
5959 Right now, all Linux kernels for PowerPC systems use the same load
5960 address (0x00000000), but the entry point address depends on the
5963 - 2.2.x kernels have the entry point at 0x0000000C,
5964 - 2.3.x and later kernels have the entry point at 0x00000000.
5966 So a typical call to build a U-Boot image would read:
5968 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
5969 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
5970 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
5971 > examples/uImage.TQM850L
5972 Image Name: 2.4.4 kernel for TQM850L
5973 Created: Wed Jul 19 02:34:59 2000
5974 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5975 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
5976 Load Address: 0x00000000
5977 Entry Point: 0x00000000
5979 To verify the contents of the image (or check for corruption):
5981 -> tools/mkimage -l examples/uImage.TQM850L
5982 Image Name: 2.4.4 kernel for TQM850L
5983 Created: Wed Jul 19 02:34:59 2000
5984 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5985 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
5986 Load Address: 0x00000000
5987 Entry Point: 0x00000000
5989 NOTE: for embedded systems where boot time is critical you can trade
5990 speed for memory and install an UNCOMPRESSED image instead: this
5991 needs more space in Flash, but boots much faster since it does not
5992 need to be uncompressed:
5994 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
5995 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
5996 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
5997 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
5998 > examples/uImage.TQM850L-uncompressed
5999 Image Name: 2.4.4 kernel for TQM850L
6000 Created: Wed Jul 19 02:34:59 2000
6001 Image Type: PowerPC Linux Kernel Image (uncompressed)
6002 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
6003 Load Address: 0x00000000
6004 Entry Point: 0x00000000
6007 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
6008 when your kernel is intended to use an initial ramdisk:
6010 -> tools/mkimage -n 'Simple Ramdisk Image' \
6011 > -A ppc -O linux -T ramdisk -C gzip \
6012 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
6013 Image Name: Simple Ramdisk Image
6014 Created: Wed Jan 12 14:01:50 2000
6015 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
6016 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
6017 Load Address: 0x00000000
6018 Entry Point: 0x00000000
6020 The "dumpimage" is a tool to disassemble images built by mkimage. Its "-i"
6021 option performs the converse operation of the mkimage's second form (the "-d"
6022 option). Given an image built by mkimage, the dumpimage extracts a "data file"
6025 tools/dumpimage -i image -T type -p position data_file
6026 -i ==> extract from the 'image' a specific 'data_file'
6027 -T ==> set image type to 'type'
6028 -p ==> 'position' (starting at 0) of the 'data_file' inside the 'image'
6031 Installing a Linux Image:
6032 -------------------------
6034 To downloading a U-Boot image over the serial (console) interface,
6035 you must convert the image to S-Record format:
6037 objcopy -I binary -O srec examples/image examples/image.srec
6039 The 'objcopy' does not understand the information in the U-Boot
6040 image header, so the resulting S-Record file will be relative to
6041 address 0x00000000. To load it to a given address, you need to
6042 specify the target address as 'offset' parameter with the 'loads'
6045 Example: install the image to address 0x40100000 (which on the
6046 TQM8xxL is in the first Flash bank):
6048 => erase 40100000 401FFFFF
6054 ## Ready for S-Record download ...
6055 ~>examples/image.srec
6056 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
6058 15989 15990 15991 15992
6059 [file transfer complete]
6061 ## Start Addr = 0x00000000
6064 You can check the success of the download using the 'iminfo' command;
6065 this includes a checksum verification so you can be sure no data
6066 corruption happened:
6070 ## Checking Image at 40100000 ...
6071 Image Name: 2.2.13 for initrd on TQM850L
6072 Image Type: PowerPC Linux Kernel Image (gzip compressed)
6073 Data Size: 335725 Bytes = 327 kB = 0 MB
6074 Load Address: 00000000
6075 Entry Point: 0000000c
6076 Verifying Checksum ... OK
6082 The "bootm" command is used to boot an application that is stored in
6083 memory (RAM or Flash). In case of a Linux kernel image, the contents
6084 of the "bootargs" environment variable is passed to the kernel as
6085 parameters. You can check and modify this variable using the
6086 "printenv" and "setenv" commands:
6089 => printenv bootargs
6090 bootargs=root=/dev/ram
6092 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
6094 => printenv bootargs
6095 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
6098 ## Booting Linux kernel at 40020000 ...
6099 Image Name: 2.2.13 for NFS on TQM850L
6100 Image Type: PowerPC Linux Kernel Image (gzip compressed)
6101 Data Size: 381681 Bytes = 372 kB = 0 MB
6102 Load Address: 00000000
6103 Entry Point: 0000000c
6104 Verifying Checksum ... OK
6105 Uncompressing Kernel Image ... OK
6106 Linux version 2.2.13 (wd@denx.local.net) (gcc version 2.95.2 19991024 (release)) #1 Wed Jul 19 02:35:17 MEST 2000
6107 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
6108 time_init: decrementer frequency = 187500000/60
6109 Calibrating delay loop... 49.77 BogoMIPS
6110 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
6113 If you want to boot a Linux kernel with initial RAM disk, you pass
6114 the memory addresses of both the kernel and the initrd image (PPBCOOT
6115 format!) to the "bootm" command:
6117 => imi 40100000 40200000
6119 ## Checking Image at 40100000 ...
6120 Image Name: 2.2.13 for initrd on TQM850L
6121 Image Type: PowerPC Linux Kernel Image (gzip compressed)
6122 Data Size: 335725 Bytes = 327 kB = 0 MB
6123 Load Address: 00000000
6124 Entry Point: 0000000c
6125 Verifying Checksum ... OK
6127 ## Checking Image at 40200000 ...
6128 Image Name: Simple Ramdisk Image
6129 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
6130 Data Size: 566530 Bytes = 553 kB = 0 MB
6131 Load Address: 00000000
6132 Entry Point: 00000000
6133 Verifying Checksum ... OK
6135 => bootm 40100000 40200000
6136 ## Booting Linux kernel at 40100000 ...
6137 Image Name: 2.2.13 for initrd on TQM850L
6138 Image Type: PowerPC Linux Kernel Image (gzip compressed)
6139 Data Size: 335725 Bytes = 327 kB = 0 MB
6140 Load Address: 00000000
6141 Entry Point: 0000000c
6142 Verifying Checksum ... OK
6143 Uncompressing Kernel Image ... OK
6144 ## Loading RAMDisk Image at 40200000 ...
6145 Image Name: Simple Ramdisk Image
6146 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
6147 Data Size: 566530 Bytes = 553 kB = 0 MB
6148 Load Address: 00000000
6149 Entry Point: 00000000
6150 Verifying Checksum ... OK
6151 Loading Ramdisk ... OK
6152 Linux version 2.2.13 (wd@denx.local.net) (gcc version 2.95.2 19991024 (release)) #1 Wed Jul 19 02:32:08 MEST 2000
6153 Boot arguments: root=/dev/ram
6154 time_init: decrementer frequency = 187500000/60
6155 Calibrating delay loop... 49.77 BogoMIPS
6157 RAMDISK: Compressed image found at block 0
6158 VFS: Mounted root (ext2 filesystem).
6162 Boot Linux and pass a flat device tree:
6165 First, U-Boot must be compiled with the appropriate defines. See the section
6166 titled "Linux Kernel Interface" above for a more in depth explanation. The
6167 following is an example of how to start a kernel and pass an updated
6173 oft=oftrees/mpc8540ads.dtb
6174 => tftp $oftaddr $oft
6175 Speed: 1000, full duplex
6177 TFTP from server 192.168.1.1; our IP address is 192.168.1.101
6178 Filename 'oftrees/mpc8540ads.dtb'.
6179 Load address: 0x300000
6182 Bytes transferred = 4106 (100a hex)
6183 => tftp $loadaddr $bootfile
6184 Speed: 1000, full duplex
6186 TFTP from server 192.168.1.1; our IP address is 192.168.1.2
6188 Load address: 0x200000
6189 Loading:############
6191 Bytes transferred = 1029407 (fb51f hex)
6196 => bootm $loadaddr - $oftaddr
6197 ## Booting image at 00200000 ...
6198 Image Name: Linux-2.6.17-dirty
6199 Image Type: PowerPC Linux Kernel Image (gzip compressed)
6200 Data Size: 1029343 Bytes = 1005.2 kB
6201 Load Address: 00000000
6202 Entry Point: 00000000
6203 Verifying Checksum ... OK
6204 Uncompressing Kernel Image ... OK
6205 Booting using flat device tree at 0x300000
6206 Using MPC85xx ADS machine description
6207 Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
6211 More About U-Boot Image Types:
6212 ------------------------------
6214 U-Boot supports the following image types:
6216 "Standalone Programs" are directly runnable in the environment
6217 provided by U-Boot; it is expected that (if they behave
6218 well) you can continue to work in U-Boot after return from
6219 the Standalone Program.
6220 "OS Kernel Images" are usually images of some Embedded OS which
6221 will take over control completely. Usually these programs
6222 will install their own set of exception handlers, device
6223 drivers, set up the MMU, etc. - this means, that you cannot
6224 expect to re-enter U-Boot except by resetting the CPU.
6225 "RAMDisk Images" are more or less just data blocks, and their
6226 parameters (address, size) are passed to an OS kernel that is
6228 "Multi-File Images" contain several images, typically an OS
6229 (Linux) kernel image and one or more data images like
6230 RAMDisks. This construct is useful for instance when you want
6231 to boot over the network using BOOTP etc., where the boot
6232 server provides just a single image file, but you want to get
6233 for instance an OS kernel and a RAMDisk image.
6235 "Multi-File Images" start with a list of image sizes, each
6236 image size (in bytes) specified by an "uint32_t" in network
6237 byte order. This list is terminated by an "(uint32_t)0".
6238 Immediately after the terminating 0 follow the images, one by
6239 one, all aligned on "uint32_t" boundaries (size rounded up to
6240 a multiple of 4 bytes).
6242 "Firmware Images" are binary images containing firmware (like
6243 U-Boot or FPGA images) which usually will be programmed to
6246 "Script files" are command sequences that will be executed by
6247 U-Boot's command interpreter; this feature is especially
6248 useful when you configure U-Boot to use a real shell (hush)
6249 as command interpreter.
6251 Booting the Linux zImage:
6252 -------------------------
6254 On some platforms, it's possible to boot Linux zImage. This is done
6255 using the "bootz" command. The syntax of "bootz" command is the same
6256 as the syntax of "bootm" command.
6258 Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply
6259 kernel with raw initrd images. The syntax is slightly different, the
6260 address of the initrd must be augmented by it's size, in the following
6261 format: "<initrd addres>:<initrd size>".
6267 One of the features of U-Boot is that you can dynamically load and
6268 run "standalone" applications, which can use some resources of
6269 U-Boot like console I/O functions or interrupt services.
6271 Two simple examples are included with the sources:
6276 'examples/hello_world.c' contains a small "Hello World" Demo
6277 application; it is automatically compiled when you build U-Boot.
6278 It's configured to run at address 0x00040004, so you can play with it
6282 ## Ready for S-Record download ...
6283 ~>examples/hello_world.srec
6284 1 2 3 4 5 6 7 8 9 10 11 ...
6285 [file transfer complete]
6287 ## Start Addr = 0x00040004
6289 => go 40004 Hello World! This is a test.
6290 ## Starting application at 0x00040004 ...
6301 Hit any key to exit ...
6303 ## Application terminated, rc = 0x0
6305 Another example, which demonstrates how to register a CPM interrupt
6306 handler with the U-Boot code, can be found in 'examples/timer.c'.
6307 Here, a CPM timer is set up to generate an interrupt every second.
6308 The interrupt service routine is trivial, just printing a '.'
6309 character, but this is just a demo program. The application can be
6310 controlled by the following keys:
6312 ? - print current values og the CPM Timer registers
6313 b - enable interrupts and start timer
6314 e - stop timer and disable interrupts
6315 q - quit application
6318 ## Ready for S-Record download ...
6319 ~>examples/timer.srec
6320 1 2 3 4 5 6 7 8 9 10 11 ...
6321 [file transfer complete]
6323 ## Start Addr = 0x00040004
6326 ## Starting application at 0x00040004 ...
6329 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
6332 [q, b, e, ?] Set interval 1000000 us
6335 [q, b, e, ?] ........
6336 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
6339 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
6342 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
6345 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
6347 [q, b, e, ?] ...Stopping timer
6349 [q, b, e, ?] ## Application terminated, rc = 0x0
6355 Over time, many people have reported problems when trying to use the
6356 "minicom" terminal emulation program for serial download. I (wd)
6357 consider minicom to be broken, and recommend not to use it. Under
6358 Unix, I recommend to use C-Kermit for general purpose use (and
6359 especially for kermit binary protocol download ("loadb" command), and
6360 use "cu" for S-Record download ("loads" command). See
6361 http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3.
6362 for help with kermit.
6365 Nevertheless, if you absolutely want to use it try adding this
6366 configuration to your "File transfer protocols" section:
6368 Name Program Name U/D FullScr IO-Red. Multi
6369 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
6370 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
6376 Starting at version 0.9.2, U-Boot supports NetBSD both as host
6377 (build U-Boot) and target system (boots NetBSD/mpc8xx).
6379 Building requires a cross environment; it is known to work on
6380 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
6381 need gmake since the Makefiles are not compatible with BSD make).
6382 Note that the cross-powerpc package does not install include files;
6383 attempting to build U-Boot will fail because <machine/ansi.h> is
6384 missing. This file has to be installed and patched manually:
6386 # cd /usr/pkg/cross/powerpc-netbsd/include
6388 # ln -s powerpc machine
6389 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
6390 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
6392 Native builds *don't* work due to incompatibilities between native
6393 and U-Boot include files.
6395 Booting assumes that (the first part of) the image booted is a
6396 stage-2 loader which in turn loads and then invokes the kernel
6397 proper. Loader sources will eventually appear in the NetBSD source
6398 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
6399 meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
6402 Implementation Internals:
6403 =========================
6405 The following is not intended to be a complete description of every
6406 implementation detail. However, it should help to understand the
6407 inner workings of U-Boot and make it easier to port it to custom
6411 Initial Stack, Global Data:
6412 ---------------------------
6414 The implementation of U-Boot is complicated by the fact that U-Boot
6415 starts running out of ROM (flash memory), usually without access to
6416 system RAM (because the memory controller is not initialized yet).
6417 This means that we don't have writable Data or BSS segments, and BSS
6418 is not initialized as zero. To be able to get a C environment working
6419 at all, we have to allocate at least a minimal stack. Implementation
6420 options for this are defined and restricted by the CPU used: Some CPU
6421 models provide on-chip memory (like the IMMR area on MPC8xx and
6422 MPC826x processors), on others (parts of) the data cache can be
6423 locked as (mis-) used as memory, etc.
6425 Chris Hallinan posted a good summary of these issues to the
6426 U-Boot mailing list:
6428 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
6429 From: "Chris Hallinan" <clh@net1plus.com>
6430 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
6433 Correct me if I'm wrong, folks, but the way I understand it
6434 is this: Using DCACHE as initial RAM for Stack, etc, does not
6435 require any physical RAM backing up the cache. The cleverness
6436 is that the cache is being used as a temporary supply of
6437 necessary storage before the SDRAM controller is setup. It's
6438 beyond the scope of this list to explain the details, but you
6439 can see how this works by studying the cache architecture and
6440 operation in the architecture and processor-specific manuals.
6442 OCM is On Chip Memory, which I believe the 405GP has 4K. It
6443 is another option for the system designer to use as an
6444 initial stack/RAM area prior to SDRAM being available. Either
6445 option should work for you. Using CS 4 should be fine if your
6446 board designers haven't used it for something that would
6447 cause you grief during the initial boot! It is frequently not
6450 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
6451 with your processor/board/system design. The default value
6452 you will find in any recent u-boot distribution in
6453 walnut.h should work for you. I'd set it to a value larger
6454 than your SDRAM module. If you have a 64MB SDRAM module, set
6455 it above 400_0000. Just make sure your board has no resources
6456 that are supposed to respond to that address! That code in
6457 start.S has been around a while and should work as is when
6458 you get the config right.
6463 It is essential to remember this, since it has some impact on the C
6464 code for the initialization procedures:
6466 * Initialized global data (data segment) is read-only. Do not attempt
6469 * Do not use any uninitialized global data (or implicitly initialized
6470 as zero data - BSS segment) at all - this is undefined, initiali-
6471 zation is performed later (when relocating to RAM).
6473 * Stack space is very limited. Avoid big data buffers or things like
6476 Having only the stack as writable memory limits means we cannot use
6477 normal global data to share information between the code. But it
6478 turned out that the implementation of U-Boot can be greatly
6479 simplified by making a global data structure (gd_t) available to all
6480 functions. We could pass a pointer to this data as argument to _all_
6481 functions, but this would bloat the code. Instead we use a feature of
6482 the GCC compiler (Global Register Variables) to share the data: we
6483 place a pointer (gd) to the global data into a register which we
6484 reserve for this purpose.
6486 When choosing a register for such a purpose we are restricted by the
6487 relevant (E)ABI specifications for the current architecture, and by
6488 GCC's implementation.
6490 For PowerPC, the following registers have specific use:
6492 R2: reserved for system use
6493 R3-R4: parameter passing and return values
6494 R5-R10: parameter passing
6495 R13: small data area pointer
6499 (U-Boot also uses R12 as internal GOT pointer. r12
6500 is a volatile register so r12 needs to be reset when
6501 going back and forth between asm and C)
6503 ==> U-Boot will use R2 to hold a pointer to the global data
6505 Note: on PPC, we could use a static initializer (since the
6506 address of the global data structure is known at compile time),
6507 but it turned out that reserving a register results in somewhat
6508 smaller code - although the code savings are not that big (on
6509 average for all boards 752 bytes for the whole U-Boot image,
6510 624 text + 127 data).
6512 On Blackfin, the normal C ABI (except for P3) is followed as documented here:
6513 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface
6515 ==> U-Boot will use P3 to hold a pointer to the global data
6517 On ARM, the following registers are used:
6519 R0: function argument word/integer result
6520 R1-R3: function argument word
6521 R9: platform specific
6522 R10: stack limit (used only if stack checking is enabled)
6523 R11: argument (frame) pointer
6524 R12: temporary workspace
6527 R15: program counter
6529 ==> U-Boot will use R9 to hold a pointer to the global data
6531 Note: on ARM, only R_ARM_RELATIVE relocations are supported.
6533 On Nios II, the ABI is documented here:
6534 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
6536 ==> U-Boot will use gp to hold a pointer to the global data
6538 Note: on Nios II, we give "-G0" option to gcc and don't use gp
6539 to access small data sections, so gp is free.
6541 On NDS32, the following registers are used:
6543 R0-R1: argument/return
6545 R15: temporary register for assembler
6546 R16: trampoline register
6547 R28: frame pointer (FP)
6548 R29: global pointer (GP)
6549 R30: link register (LP)
6550 R31: stack pointer (SP)
6551 PC: program counter (PC)
6553 ==> U-Boot will use R10 to hold a pointer to the global data
6555 NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
6556 or current versions of GCC may "optimize" the code too much.
6561 U-Boot runs in system state and uses physical addresses, i.e. the
6562 MMU is not used either for address mapping nor for memory protection.
6564 The available memory is mapped to fixed addresses using the memory
6565 controller. In this process, a contiguous block is formed for each
6566 memory type (Flash, SDRAM, SRAM), even when it consists of several
6567 physical memory banks.
6569 U-Boot is installed in the first 128 kB of the first Flash bank (on
6570 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
6571 booting and sizing and initializing DRAM, the code relocates itself
6572 to the upper end of DRAM. Immediately below the U-Boot code some
6573 memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
6574 configuration setting]. Below that, a structure with global Board
6575 Info data is placed, followed by the stack (growing downward).
6577 Additionally, some exception handler code is copied to the low 8 kB
6578 of DRAM (0x00000000 ... 0x00001FFF).
6580 So a typical memory configuration with 16 MB of DRAM could look like
6583 0x0000 0000 Exception Vector code
6586 0x0000 2000 Free for Application Use
6592 0x00FB FF20 Monitor Stack (Growing downward)
6593 0x00FB FFAC Board Info Data and permanent copy of global data
6594 0x00FC 0000 Malloc Arena
6597 0x00FE 0000 RAM Copy of Monitor Code
6598 ... eventually: LCD or video framebuffer
6599 ... eventually: pRAM (Protected RAM - unchanged by reset)
6600 0x00FF FFFF [End of RAM]
6603 System Initialization:
6604 ----------------------
6606 In the reset configuration, U-Boot starts at the reset entry point
6607 (on most PowerPC systems at address 0x00000100). Because of the reset
6608 configuration for CS0# this is a mirror of the on board Flash memory.
6609 To be able to re-map memory U-Boot then jumps to its link address.
6610 To be able to implement the initialization code in C, a (small!)
6611 initial stack is set up in the internal Dual Ported RAM (in case CPUs
6612 which provide such a feature like MPC8xx or MPC8260), or in a locked
6613 part of the data cache. After that, U-Boot initializes the CPU core,
6614 the caches and the SIU.
6616 Next, all (potentially) available memory banks are mapped using a
6617 preliminary mapping. For example, we put them on 512 MB boundaries
6618 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
6619 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
6620 programmed for SDRAM access. Using the temporary configuration, a
6621 simple memory test is run that determines the size of the SDRAM
6624 When there is more than one SDRAM bank, and the banks are of
6625 different size, the largest is mapped first. For equal size, the first
6626 bank (CS2#) is mapped first. The first mapping is always for address
6627 0x00000000, with any additional banks following immediately to create
6628 contiguous memory starting from 0.
6630 Then, the monitor installs itself at the upper end of the SDRAM area
6631 and allocates memory for use by malloc() and for the global Board
6632 Info data; also, the exception vector code is copied to the low RAM
6633 pages, and the final stack is set up.
6635 Only after this relocation will you have a "normal" C environment;
6636 until that you are restricted in several ways, mostly because you are
6637 running from ROM, and because the code will have to be relocated to a
6641 U-Boot Porting Guide:
6642 ----------------------
6644 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
6648 int main(int argc, char *argv[])
6650 sighandler_t no_more_time;
6652 signal(SIGALRM, no_more_time);
6653 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
6655 if (available_money > available_manpower) {
6656 Pay consultant to port U-Boot;
6660 Download latest U-Boot source;
6662 Subscribe to u-boot mailing list;
6665 email("Hi, I am new to U-Boot, how do I get started?");
6668 Read the README file in the top level directory;
6669 Read http://www.denx.de/twiki/bin/view/DULG/Manual;
6670 Read applicable doc/*.README;
6671 Read the source, Luke;
6672 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
6675 if (available_money > toLocalCurrency ($2500))
6678 Add a lot of aggravation and time;
6680 if (a similar board exists) { /* hopefully... */
6681 cp -a board/<similar> board/<myboard>
6682 cp include/configs/<similar>.h include/configs/<myboard>.h
6684 Create your own board support subdirectory;
6685 Create your own board include/configs/<myboard>.h file;
6687 Edit new board/<myboard> files
6688 Edit new include/configs/<myboard>.h
6693 Add / modify source code;
6697 email("Hi, I am having problems...");
6699 Send patch file to the U-Boot email list;
6700 if (reasonable critiques)
6701 Incorporate improvements from email list code review;
6703 Defend code as written;
6709 void no_more_time (int sig)
6718 All contributions to U-Boot should conform to the Linux kernel
6719 coding style; see the file "Documentation/CodingStyle" and the script
6720 "scripts/Lindent" in your Linux kernel source directory.
6722 Source files originating from a different project (for example the
6723 MTD subsystem) are generally exempt from these guidelines and are not
6724 reformatted to ease subsequent migration to newer versions of those
6727 Please note that U-Boot is implemented in C (and to some small parts in
6728 Assembler); no C++ is used, so please do not use C++ style comments (//)
6731 Please also stick to the following formatting rules:
6732 - remove any trailing white space
6733 - use TAB characters for indentation and vertical alignment, not spaces
6734 - make sure NOT to use DOS '\r\n' line feeds
6735 - do not add more than 2 consecutive empty lines to source files
6736 - do not add trailing empty lines to source files
6738 Submissions which do not conform to the standards may be returned
6739 with a request to reformat the changes.
6745 Since the number of patches for U-Boot is growing, we need to
6746 establish some rules. Submissions which do not conform to these rules
6747 may be rejected, even when they contain important and valuable stuff.
6749 Please see http://www.denx.de/wiki/U-Boot/Patches for details.
6751 Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
6752 see http://lists.denx.de/mailman/listinfo/u-boot
6754 When you send a patch, please include the following information with
6757 * For bug fixes: a description of the bug and how your patch fixes
6758 this bug. Please try to include a way of demonstrating that the
6759 patch actually fixes something.
6761 * For new features: a description of the feature and your
6764 * A CHANGELOG entry as plaintext (separate from the patch)
6766 * For major contributions, your entry to the CREDITS file
6768 * When you add support for a new board, don't forget to add a
6769 maintainer e-mail address to the boards.cfg file, too.
6771 * If your patch adds new configuration options, don't forget to
6772 document these in the README file.
6774 * The patch itself. If you are using git (which is *strongly*
6775 recommended) you can easily generate the patch using the
6776 "git format-patch". If you then use "git send-email" to send it to
6777 the U-Boot mailing list, you will avoid most of the common problems
6778 with some other mail clients.
6780 If you cannot use git, use "diff -purN OLD NEW". If your version of
6781 diff does not support these options, then get the latest version of
6784 The current directory when running this command shall be the parent
6785 directory of the U-Boot source tree (i. e. please make sure that
6786 your patch includes sufficient directory information for the
6789 We prefer patches as plain text. MIME attachments are discouraged,
6790 and compressed attachments must not be used.
6792 * If one logical set of modifications affects or creates several
6793 files, all these changes shall be submitted in a SINGLE patch file.
6795 * Changesets that contain different, unrelated modifications shall be
6796 submitted as SEPARATE patches, one patch per changeset.
6801 * Before sending the patch, run the MAKEALL script on your patched
6802 source tree and make sure that no errors or warnings are reported
6803 for any of the boards.
6805 * Keep your modifications to the necessary minimum: A patch
6806 containing several unrelated changes or arbitrary reformats will be
6807 returned with a request to re-formatting / split it.
6809 * If you modify existing code, make sure that your new code does not
6810 add to the memory footprint of the code ;-) Small is beautiful!
6811 When adding new features, these should compile conditionally only
6812 (using #ifdef), and the resulting code with the new feature
6813 disabled must not need more memory than the old code without your
6816 * Remember that there is a size limit of 100 kB per message on the
6817 u-boot mailing list. Bigger patches will be moderated. If they are
6818 reasonable and not too big, they will be acknowledged. But patches
6819 bigger than the size limit should be avoided.
projects / karo-tx-uboot.git / blob