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 /arm Files generic to ARM architecture
136 /cpu CPU specific files
137 /arm720t Files specific to ARM 720 CPUs
138 /arm920t Files specific to ARM 920 CPUs
139 /at91 Files specific to Atmel AT91RM9200 CPU
140 /imx Files specific to Freescale MC9328 i.MX CPUs
141 /s3c24x0 Files specific to Samsung S3C24X0 CPUs
142 /arm926ejs Files specific to ARM 926 CPUs
143 /arm1136 Files specific to ARM 1136 CPUs
144 /pxa Files specific to Intel XScale PXA CPUs
145 /sa1100 Files specific to Intel StrongARM SA1100 CPUs
146 /lib Architecture specific library files
147 /avr32 Files generic to AVR32 architecture
148 /cpu CPU specific files
149 /lib Architecture specific library files
150 /blackfin Files generic to Analog Devices Blackfin architecture
151 /cpu CPU specific files
152 /lib Architecture specific library files
153 /m68k Files generic to m68k architecture
154 /cpu CPU specific files
155 /mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs
156 /mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs
157 /mcf532x Files specific to Freescale ColdFire MCF5329 CPUs
158 /mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs
159 /mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs
160 /lib Architecture specific library files
161 /microblaze Files generic to microblaze architecture
162 /cpu CPU specific files
163 /lib Architecture specific library files
164 /mips Files generic to MIPS architecture
165 /cpu CPU specific files
166 /mips32 Files specific to MIPS32 CPUs
167 /xburst Files specific to Ingenic XBurst CPUs
168 /lib Architecture specific library files
169 /nds32 Files generic to NDS32 architecture
170 /cpu CPU specific files
171 /n1213 Files specific to Andes Technology N1213 CPUs
172 /lib Architecture specific library files
173 /nios2 Files generic to Altera NIOS2 architecture
174 /cpu CPU specific files
175 /lib Architecture specific library files
176 /openrisc Files generic to OpenRISC architecture
177 /cpu CPU specific files
178 /lib Architecture specific library files
179 /powerpc Files generic to PowerPC architecture
180 /cpu CPU specific files
181 /74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs
182 /mpc5xx Files specific to Freescale MPC5xx CPUs
183 /mpc5xxx Files specific to Freescale MPC5xxx CPUs
184 /mpc8xx Files specific to Freescale MPC8xx CPUs
185 /mpc824x Files specific to Freescale MPC824x CPUs
186 /mpc8260 Files specific to Freescale MPC8260 CPUs
187 /mpc85xx Files specific to Freescale MPC85xx CPUs
188 /ppc4xx Files specific to AMCC PowerPC 4xx CPUs
189 /lib Architecture specific library files
190 /sh Files generic to SH architecture
191 /cpu CPU specific files
192 /sh2 Files specific to sh2 CPUs
193 /sh3 Files specific to sh3 CPUs
194 /sh4 Files specific to sh4 CPUs
195 /lib Architecture specific library files
196 /sparc Files generic to SPARC architecture
197 /cpu CPU specific files
198 /leon2 Files specific to Gaisler LEON2 SPARC CPU
199 /leon3 Files specific to Gaisler LEON3 SPARC CPU
200 /lib Architecture specific library files
201 /x86 Files generic to x86 architecture
202 /cpu CPU specific files
203 /lib Architecture specific library files
204 /api Machine/arch independent API for external apps
205 /board Board dependent files
206 /common Misc architecture independent functions
207 /disk Code for disk drive partition handling
208 /doc Documentation (don't expect too much)
209 /drivers Commonly used device drivers
210 /dts Contains Makefile for building internal U-Boot fdt.
211 /examples Example code for standalone applications, etc.
212 /fs Filesystem code (cramfs, ext2, jffs2, etc.)
213 /include Header Files
214 /lib Files generic to all architectures
215 /libfdt Library files to support flattened device trees
216 /lzma Library files to support LZMA decompression
217 /lzo Library files to support LZO decompression
219 /post Power On Self Test
220 /spl Secondary Program Loader framework
221 /tools Tools to build S-Record or U-Boot images, etc.
223 Software Configuration:
224 =======================
226 Configuration is usually done using C preprocessor defines; the
227 rationale behind that is to avoid dead code whenever possible.
229 There are two classes of configuration variables:
231 * Configuration _OPTIONS_:
232 These are selectable by the user and have names beginning with
235 * Configuration _SETTINGS_:
236 These depend on the hardware etc. and should not be meddled with if
237 you don't know what you're doing; they have names beginning with
240 Later we will add a configuration tool - probably similar to or even
241 identical to what's used for the Linux kernel. Right now, we have to
242 do the configuration by hand, which means creating some symbolic
243 links and editing some configuration files. We use the TQM8xxL boards
247 Selection of Processor Architecture and Board Type:
248 ---------------------------------------------------
250 For all supported boards there are ready-to-use default
251 configurations available; just type "make <board_name>_config".
253 Example: For a TQM823L module type:
258 For the Cogent platform, you need to specify the CPU type as well;
259 e.g. "make cogent_mpc8xx_config". And also configure the cogent
260 directory according to the instructions in cogent/README.
263 Configuration Options:
264 ----------------------
266 Configuration depends on the combination of board and CPU type; all
267 such information is kept in a configuration file
268 "include/configs/<board_name>.h".
270 Example: For a TQM823L module, all configuration settings are in
271 "include/configs/TQM823L.h".
274 Many of the options are named exactly as the corresponding Linux
275 kernel configuration options. The intention is to make it easier to
276 build a config tool - later.
279 The following options need to be configured:
281 - CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
283 - Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
285 - CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined)
286 Define exactly one, e.g. CONFIG_ATSTK1002
288 - CPU Module Type: (if CONFIG_COGENT is defined)
289 Define exactly one of
291 --- FIXME --- not tested yet:
292 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
293 CONFIG_CMA287_23, CONFIG_CMA287_50
295 - Motherboard Type: (if CONFIG_COGENT is defined)
296 Define exactly one of
297 CONFIG_CMA101, CONFIG_CMA102
299 - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
300 Define one or more of
303 - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
304 Define one or more of
305 CONFIG_LCD_HEARTBEAT - update a character position on
306 the LCD display every second with
309 - Board flavour: (if CONFIG_MPC8260ADS is defined)
312 CONFIG_SYS_8260ADS - original MPC8260ADS
313 CONFIG_SYS_8266ADS - MPC8266ADS
314 CONFIG_SYS_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR
315 CONFIG_SYS_8272ADS - MPC8272ADS
317 - Marvell Family Member
318 CONFIG_SYS_MVFS - define it if you want to enable
319 multiple fs option at one time
320 for marvell soc family
322 - MPC824X Family Member (if CONFIG_MPC824X is defined)
323 Define exactly one of
324 CONFIG_MPC8240, CONFIG_MPC8245
326 - 8xx CPU Options: (if using an MPC8xx CPU)
327 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if
328 get_gclk_freq() cannot work
329 e.g. if there is no 32KHz
330 reference PIT/RTC clock
331 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK
334 - 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
335 CONFIG_SYS_8xx_CPUCLK_MIN
336 CONFIG_SYS_8xx_CPUCLK_MAX
337 CONFIG_8xx_CPUCLK_DEFAULT
338 See doc/README.MPC866
340 CONFIG_SYS_MEASURE_CPUCLK
342 Define this to measure the actual CPU clock instead
343 of relying on the correctness of the configured
344 values. Mostly useful for board bringup to make sure
345 the PLL is locked at the intended frequency. Note
346 that this requires a (stable) reference clock (32 kHz
347 RTC clock or CONFIG_SYS_8XX_XIN)
349 CONFIG_SYS_DELAYED_ICACHE
351 Define this option if you want to enable the
352 ICache only when Code runs from RAM.
357 Specifies that the core is a 64-bit PowerPC implementation (implements
358 the "64" category of the Power ISA). This is necessary for ePAPR
359 compliance, among other possible reasons.
361 CONFIG_SYS_FSL_TBCLK_DIV
363 Defines the core time base clock divider ratio compared to the
364 system clock. On most PQ3 devices this is 8, on newer QorIQ
365 devices it can be 16 or 32. The ratio varies from SoC to Soc.
367 CONFIG_SYS_FSL_PCIE_COMPAT
369 Defines the string to utilize when trying to match PCIe device
370 tree nodes for the given platform.
372 CONFIG_SYS_PPC_E500_DEBUG_TLB
374 Enables a temporary TLB entry to be used during boot to work
375 around limitations in e500v1 and e500v2 external debugger
376 support. This reduces the portions of the boot code where
377 breakpoints and single stepping do not work. The value of this
378 symbol should be set to the TLB1 entry to be used for this
381 CONFIG_SYS_FSL_ERRATUM_A004510
383 Enables a workaround for erratum A004510. If set,
384 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and
385 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set.
387 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV
388 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional)
390 Defines one or two SoC revisions (low 8 bits of SVR)
391 for which the A004510 workaround should be applied.
393 The rest of SVR is either not relevant to the decision
394 of whether the erratum is present (e.g. p2040 versus
395 p2041) or is implied by the build target, which controls
396 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set.
398 See Freescale App Note 4493 for more information about
401 CONFIG_A003399_NOR_WORKAROUND
402 Enables a workaround for IFC erratum A003399. It is only
403 requred during NOR boot.
405 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY
407 This is the value to write into CCSR offset 0x18600
408 according to the A004510 workaround.
410 CONFIG_SYS_FSL_DSP_DDR_ADDR
411 This value denotes start offset of DDR memory which is
412 connected exclusively to the DSP cores.
414 CONFIG_SYS_FSL_DSP_M2_RAM_ADDR
415 This value denotes start offset of M2 memory
416 which is directly connected to the DSP core.
418 CONFIG_SYS_FSL_DSP_M3_RAM_ADDR
419 This value denotes start offset of M3 memory which is directly
420 connected to the DSP core.
422 CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT
423 This value denotes start offset of DSP CCSR space.
425 CONFIG_SYS_FSL_SINGLE_SOURCE_CLK
426 Single Source Clock is clocking mode present in some of FSL SoC's.
427 In this mode, a single differential clock is used to supply
428 clocks to the sysclock, ddrclock and usbclock.
430 CONFIG_SYS_CPC_REINIT_F
431 This CONFIG is defined when the CPC is configured as SRAM at the
432 time of U-boot entry and is required to be re-initialized.
434 - Generic CPU options:
435 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN
437 Defines the endianess of the CPU. Implementation of those
438 values is arch specific.
441 Freescale DDR driver in use. This type of DDR controller is
442 found in mpc83xx, mpc85xx, mpc86xx as well as some ARM core
445 CONFIG_SYS_FSL_DDR_ADDR
446 Freescale DDR memory-mapped register base.
448 CONFIG_SYS_FSL_DDR_EMU
449 Specify emulator support for DDR. Some DDR features such as
450 deskew training are not available.
452 CONFIG_SYS_FSL_DDRC_GEN1
453 Freescale DDR1 controller.
455 CONFIG_SYS_FSL_DDRC_GEN2
456 Freescale DDR2 controller.
458 CONFIG_SYS_FSL_DDRC_GEN3
459 Freescale DDR3 controller.
461 CONFIG_SYS_FSL_DDRC_GEN4
462 Freescale DDR4 controller.
464 CONFIG_SYS_FSL_DDRC_ARM_GEN3
465 Freescale DDR3 controller for ARM-based SoCs.
468 Board config to use DDR1. It can be enabled for SoCs with
469 Freescale DDR1 or DDR2 controllers, depending on the board
473 Board config to use DDR2. It can be eanbeld for SoCs with
474 Freescale DDR2 or DDR3 controllers, depending on the board
478 Board config to use DDR3. It can be enabled for SoCs with
479 Freescale DDR3 or DDR3L controllers.
482 Board config to use DDR3L. It can be enabled for SoCs with
486 Board config to use DDR4. It can be enabled for SoCs with
489 CONFIG_SYS_FSL_IFC_BE
490 Defines the IFC controller register space as Big Endian
492 CONFIG_SYS_FSL_IFC_LE
493 Defines the IFC controller register space as Little Endian
495 CONFIG_SYS_FSL_PBL_PBI
496 It enables addition of RCW (Power on reset configuration) in built image.
497 Please refer doc/README.pblimage for more details
499 CONFIG_SYS_FSL_PBL_RCW
500 It adds PBI(pre-boot instructions) commands in u-boot build image.
501 PBI commands can be used to configure SoC before it starts the execution.
502 Please refer doc/README.pblimage for more details
504 CONFIG_SYS_FSL_DDR_BE
505 Defines the DDR controller register space as Big Endian
507 CONFIG_SYS_FSL_DDR_LE
508 Defines the DDR controller register space as Little Endian
510 CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY
511 Physical address from the view of DDR controllers. It is the
512 same as CONFIG_SYS_DDR_SDRAM_BASE for all Power SoCs. But
513 it could be different for ARM SoCs.
515 CONFIG_SYS_FSL_DDR_INTLV_256B
516 DDR controller interleaving on 256-byte. This is a special
517 interleaving mode, handled by Dickens for Freescale layerscape
520 - Intel Monahans options:
521 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO
523 Defines the Monahans run mode to oscillator
524 ratio. Valid values are 8, 16, 24, 31. The core
525 frequency is this value multiplied by 13 MHz.
527 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO
529 Defines the Monahans turbo mode to oscillator
530 ratio. Valid values are 1 (default if undefined) and
531 2. The core frequency as calculated above is multiplied
535 CONFIG_SYS_INIT_SP_OFFSET
537 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack
538 pointer. This is needed for the temporary stack before
541 CONFIG_SYS_MIPS_CACHE_MODE
543 Cache operation mode for the MIPS CPU.
544 See also arch/mips/include/asm/mipsregs.h.
546 CONF_CM_CACHABLE_NO_WA
549 CONF_CM_CACHABLE_NONCOHERENT
553 CONF_CM_CACHABLE_ACCELERATED
555 CONFIG_SYS_XWAY_EBU_BOOTCFG
557 Special option for Lantiq XWAY SoCs for booting from NOR flash.
558 See also arch/mips/cpu/mips32/start.S.
560 CONFIG_XWAY_SWAP_BYTES
562 Enable compilation of tools/xway-swap-bytes needed for Lantiq
563 XWAY SoCs for booting from NOR flash. The U-Boot image needs to
564 be swapped if a flash programmer is used.
567 CONFIG_SYS_EXCEPTION_VECTORS_HIGH
569 Select high exception vectors of the ARM core, e.g., do not
570 clear the V bit of the c1 register of CP15.
572 CONFIG_SYS_THUMB_BUILD
574 Use this flag to build U-Boot using the Thumb instruction
575 set for ARM architectures. Thumb instruction set provides
576 better code density. For ARM architectures that support
577 Thumb2 this flag will result in Thumb2 code generated by
580 CONFIG_ARM_ERRATA_716044
581 CONFIG_ARM_ERRATA_742230
582 CONFIG_ARM_ERRATA_743622
583 CONFIG_ARM_ERRATA_751472
584 CONFIG_ARM_ERRATA_794072
585 CONFIG_ARM_ERRATA_761320
587 If set, the workarounds for these ARM errata are applied early
588 during U-Boot startup. Note that these options force the
589 workarounds to be applied; no CPU-type/version detection
590 exists, unlike the similar options in the Linux kernel. Do not
591 set these options unless they apply!
596 The frequency of the timer returned by get_timer().
597 get_timer() must operate in milliseconds and this CONFIG
598 option must be set to 1000.
600 - Linux Kernel Interface:
603 U-Boot stores all clock information in Hz
604 internally. For binary compatibility with older Linux
605 kernels (which expect the clocks passed in the
606 bd_info data to be in MHz) the environment variable
607 "clocks_in_mhz" can be defined so that U-Boot
608 converts clock data to MHZ before passing it to the
610 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
611 "clocks_in_mhz=1" is automatically included in the
614 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
616 When transferring memsize parameter to linux, some versions
617 expect it to be in bytes, others in MB.
618 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
622 New kernel versions are expecting firmware settings to be
623 passed using flattened device trees (based on open firmware
627 * New libfdt-based support
628 * Adds the "fdt" command
629 * The bootm command automatically updates the fdt
631 OF_CPU - The proper name of the cpus node (only required for
632 MPC512X and MPC5xxx based boards).
633 OF_SOC - The proper name of the soc node (only required for
634 MPC512X and MPC5xxx based boards).
635 OF_TBCLK - The timebase frequency.
636 OF_STDOUT_PATH - The path to the console device
638 boards with QUICC Engines require OF_QE to set UCC MAC
641 CONFIG_OF_BOARD_SETUP
643 Board code has addition modification that it wants to make
644 to the flat device tree before handing it off to the kernel
648 This define fills in the correct boot CPU in the boot
649 param header, the default value is zero if undefined.
653 U-Boot can detect if an IDE device is present or not.
654 If not, and this new config option is activated, U-Boot
655 removes the ATA node from the DTS before booting Linux,
656 so the Linux IDE driver does not probe the device and
657 crash. This is needed for buggy hardware (uc101) where
658 no pull down resistor is connected to the signal IDE5V_DD7.
660 CONFIG_MACH_TYPE [relevant for ARM only][mandatory]
662 This setting is mandatory for all boards that have only one
663 machine type and must be used to specify the machine type
664 number as it appears in the ARM machine registry
665 (see http://www.arm.linux.org.uk/developer/machines/).
666 Only boards that have multiple machine types supported
667 in a single configuration file and the machine type is
668 runtime discoverable, do not have to use this setting.
670 - vxWorks boot parameters:
672 bootvx constructs a valid bootline using the following
673 environments variables: bootfile, ipaddr, serverip, hostname.
674 It loads the vxWorks image pointed bootfile.
676 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name
677 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address
678 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server
679 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters
681 CONFIG_SYS_VXWORKS_ADD_PARAMS
683 Add it at the end of the bootline. E.g "u=username pw=secret"
685 Note: If a "bootargs" environment is defined, it will overwride
686 the defaults discussed just above.
688 - Cache Configuration:
689 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot
690 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot
691 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot
693 - Cache Configuration for ARM:
694 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache
696 CONFIG_SYS_PL310_BASE - Physical base address of PL310
697 controller register space
702 Define this if you want support for Amba PrimeCell PL010 UARTs.
706 Define this if you want support for Amba PrimeCell PL011 UARTs.
710 If you have Amba PrimeCell PL011 UARTs, set this variable to
711 the clock speed of the UARTs.
715 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
716 define this to a list of base addresses for each (supported)
717 port. See e.g. include/configs/versatile.h
719 CONFIG_PL011_SERIAL_RLCR
721 Some vendor versions of PL011 serial ports (e.g. ST-Ericsson U8500)
722 have separate receive and transmit line control registers. Set
723 this variable to initialize the extra register.
725 CONFIG_PL011_SERIAL_FLUSH_ON_INIT
727 On some platforms (e.g. U8500) U-Boot is loaded by a second stage
728 boot loader that has already initialized the UART. Define this
729 variable to flush the UART at init time.
733 Depending on board, define exactly one serial port
734 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
735 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
736 console by defining CONFIG_8xx_CONS_NONE
738 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
739 port routines must be defined elsewhere
740 (i.e. serial_init(), serial_getc(), ...)
743 Enables console device for a color framebuffer. Needs following
744 defines (cf. smiLynxEM, i8042)
745 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
747 VIDEO_HW_RECTFILL graphic chip supports
750 VIDEO_HW_BITBLT graphic chip supports
751 bit-blit (cf. smiLynxEM)
752 VIDEO_VISIBLE_COLS visible pixel columns
754 VIDEO_VISIBLE_ROWS visible pixel rows
755 VIDEO_PIXEL_SIZE bytes per pixel
756 VIDEO_DATA_FORMAT graphic data format
757 (0-5, cf. cfb_console.c)
758 VIDEO_FB_ADRS framebuffer address
759 VIDEO_KBD_INIT_FCT keyboard int fct
760 (i.e. i8042_kbd_init())
761 VIDEO_TSTC_FCT test char fct
763 VIDEO_GETC_FCT get char fct
765 CONFIG_CONSOLE_CURSOR cursor drawing on/off
766 (requires blink timer
768 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
769 CONFIG_CONSOLE_TIME display time/date info in
771 (requires CONFIG_CMD_DATE)
772 CONFIG_VIDEO_LOGO display Linux logo in
774 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
775 linux_logo.h for logo.
776 Requires CONFIG_VIDEO_LOGO
777 CONFIG_CONSOLE_EXTRA_INFO
778 additional board info beside
781 When CONFIG_CFB_CONSOLE_ANSI is defined, console will support
782 a limited number of ANSI escape sequences (cursor control,
783 erase functions and limited graphics rendition control).
785 When CONFIG_CFB_CONSOLE is defined, video console is
786 default i/o. Serial console can be forced with
787 environment 'console=serial'.
789 When CONFIG_SILENT_CONSOLE is defined, all console
790 messages (by U-Boot and Linux!) can be silenced with
791 the "silent" environment variable. See
792 doc/README.silent for more information.
794 CONFIG_SYS_CONSOLE_BG_COL: define the backgroundcolor, default
796 CONFIG_SYS_CONSOLE_FG_COL: define the foregroundcolor, default
800 CONFIG_BAUDRATE - in bps
801 Select one of the baudrates listed in
802 CONFIG_SYS_BAUDRATE_TABLE, see below.
803 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale
805 - Console Rx buffer length
806 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define
807 the maximum receive buffer length for the SMC.
808 This option is actual only for 82xx and 8xx possible.
809 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE
810 must be defined, to setup the maximum idle timeout for
813 - Pre-Console Buffer:
814 Prior to the console being initialised (i.e. serial UART
815 initialised etc) all console output is silently discarded.
816 Defining CONFIG_PRE_CONSOLE_BUFFER will cause U-Boot to
817 buffer any console messages prior to the console being
818 initialised to a buffer of size CONFIG_PRE_CON_BUF_SZ
819 bytes located at CONFIG_PRE_CON_BUF_ADDR. The buffer is
820 a circular buffer, so if more than CONFIG_PRE_CON_BUF_SZ
821 bytes are output before the console is initialised, the
822 earlier bytes are discarded.
824 'Sane' compilers will generate smaller code if
825 CONFIG_PRE_CON_BUF_SZ is a power of 2
827 - Safe printf() functions
828 Define CONFIG_SYS_VSNPRINTF to compile in safe versions of
829 the printf() functions. These are defined in
830 include/vsprintf.h and include snprintf(), vsnprintf() and
831 so on. Code size increase is approximately 300-500 bytes.
832 If this option is not given then these functions will
833 silently discard their buffer size argument - this means
834 you are not getting any overflow checking in this case.
836 - Boot Delay: CONFIG_BOOTDELAY - in seconds
837 Delay before automatically booting the default image;
838 set to -1 to disable autoboot.
839 set to -2 to autoboot with no delay and not check for abort
840 (even when CONFIG_ZERO_BOOTDELAY_CHECK is defined).
842 See doc/README.autoboot for these options that
843 work with CONFIG_BOOTDELAY. None are required.
844 CONFIG_BOOT_RETRY_TIME
845 CONFIG_BOOT_RETRY_MIN
846 CONFIG_AUTOBOOT_KEYED
847 CONFIG_AUTOBOOT_PROMPT
848 CONFIG_AUTOBOOT_DELAY_STR
849 CONFIG_AUTOBOOT_STOP_STR
850 CONFIG_AUTOBOOT_DELAY_STR2
851 CONFIG_AUTOBOOT_STOP_STR2
852 CONFIG_ZERO_BOOTDELAY_CHECK
853 CONFIG_RESET_TO_RETRY
857 Only needed when CONFIG_BOOTDELAY is enabled;
858 define a command string that is automatically executed
859 when no character is read on the console interface
860 within "Boot Delay" after reset.
863 This can be used to pass arguments to the bootm
864 command. The value of CONFIG_BOOTARGS goes into the
865 environment value "bootargs".
867 CONFIG_RAMBOOT and CONFIG_NFSBOOT
868 The value of these goes into the environment as
869 "ramboot" and "nfsboot" respectively, and can be used
870 as a convenience, when switching between booting from
874 CONFIG_BOOTCOUNT_LIMIT
875 Implements a mechanism for detecting a repeating reboot
877 http://www.denx.de/wiki/view/DULG/UBootBootCountLimit
880 If no softreset save registers are found on the hardware
881 "bootcount" is stored in the environment. To prevent a
882 saveenv on all reboots, the environment variable
883 "upgrade_available" is used. If "upgrade_available" is
884 0, "bootcount" is always 0, if "upgrade_available" is
885 1 "bootcount" is incremented in the environment.
886 So the Userspace Applikation must set the "upgrade_available"
887 and "bootcount" variable to 0, if a boot was successfully.
892 When this option is #defined, the existence of the
893 environment variable "preboot" will be checked
894 immediately before starting the CONFIG_BOOTDELAY
895 countdown and/or running the auto-boot command resp.
896 entering interactive mode.
898 This feature is especially useful when "preboot" is
899 automatically generated or modified. For an example
900 see the LWMON board specific code: here "preboot" is
901 modified when the user holds down a certain
902 combination of keys on the (special) keyboard when
905 - Serial Download Echo Mode:
907 If defined to 1, all characters received during a
908 serial download (using the "loads" command) are
909 echoed back. This might be needed by some terminal
910 emulations (like "cu"), but may as well just take
911 time on others. This setting #define's the initial
912 value of the "loads_echo" environment variable.
914 - Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
916 Select one of the baudrates listed in
917 CONFIG_SYS_BAUDRATE_TABLE, see below.
920 Monitor commands can be included or excluded
921 from the build by using the #include files
922 <config_cmd_all.h> and #undef'ing unwanted
923 commands, or using <config_cmd_default.h>
924 and augmenting with additional #define's
927 The default command configuration includes all commands
928 except those marked below with a "*".
930 CONFIG_CMD_AES AES 128 CBC encrypt/decrypt
931 CONFIG_CMD_ASKENV * ask for env variable
932 CONFIG_CMD_BDI bdinfo
933 CONFIG_CMD_BEDBUG * Include BedBug Debugger
934 CONFIG_CMD_BMP * BMP support
935 CONFIG_CMD_BSP * Board specific commands
936 CONFIG_CMD_BOOTD bootd
937 CONFIG_CMD_CACHE * icache, dcache
938 CONFIG_CMD_CLK * clock command support
939 CONFIG_CMD_CONSOLE coninfo
940 CONFIG_CMD_CRC32 * crc32
941 CONFIG_CMD_DATE * support for RTC, date/time...
942 CONFIG_CMD_DHCP * DHCP support
943 CONFIG_CMD_DIAG * Diagnostics
944 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands
945 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command
946 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd
947 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command
948 CONFIG_CMD_DTT * Digital Therm and Thermostat
949 CONFIG_CMD_ECHO echo arguments
950 CONFIG_CMD_EDITENV edit env variable
951 CONFIG_CMD_EEPROM * EEPROM read/write support
952 CONFIG_CMD_ELF * bootelf, bootvx
953 CONFIG_CMD_ENV_CALLBACK * display details about env callbacks
954 CONFIG_CMD_ENV_FLAGS * display details about env flags
955 CONFIG_CMD_ENV_EXISTS * check existence of env variable
956 CONFIG_CMD_EXPORTENV * export the environment
957 CONFIG_CMD_EXT2 * ext2 command support
958 CONFIG_CMD_EXT4 * ext4 command support
959 CONFIG_CMD_FS_GENERIC * filesystem commands (e.g. load, ls)
960 that work for multiple fs types
961 CONFIG_CMD_SAVEENV saveenv
962 CONFIG_CMD_FDC * Floppy Disk Support
963 CONFIG_CMD_FAT * FAT command support
964 CONFIG_CMD_FLASH flinfo, erase, protect
965 CONFIG_CMD_FPGA FPGA device initialization support
966 CONFIG_CMD_FUSE * Device fuse support
967 CONFIG_CMD_GETTIME * Get time since boot
968 CONFIG_CMD_GO * the 'go' command (exec code)
969 CONFIG_CMD_GREPENV * search environment
970 CONFIG_CMD_HASH * calculate hash / digest
971 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control
972 CONFIG_CMD_I2C * I2C serial bus support
973 CONFIG_CMD_IDE * IDE harddisk support
974 CONFIG_CMD_IMI iminfo
975 CONFIG_CMD_IMLS List all images found in NOR flash
976 CONFIG_CMD_IMLS_NAND * List all images found in NAND flash
977 CONFIG_CMD_IMMAP * IMMR dump support
978 CONFIG_CMD_IMPORTENV * import an environment
979 CONFIG_CMD_INI * import data from an ini file into the env
980 CONFIG_CMD_IRQ * irqinfo
981 CONFIG_CMD_ITEST Integer/string test of 2 values
982 CONFIG_CMD_JFFS2 * JFFS2 Support
983 CONFIG_CMD_KGDB * kgdb
984 CONFIG_CMD_LDRINFO * ldrinfo (display Blackfin loader)
985 CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration
987 CONFIG_CMD_LOADB loadb
988 CONFIG_CMD_LOADS loads
989 CONFIG_CMD_MD5SUM * print md5 message digest
990 (requires CONFIG_CMD_MEMORY and CONFIG_MD5)
991 CONFIG_CMD_MEMINFO * Display detailed memory information
992 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
994 CONFIG_CMD_MEMTEST * mtest
995 CONFIG_CMD_MISC Misc functions like sleep etc
996 CONFIG_CMD_MMC * MMC memory mapped support
997 CONFIG_CMD_MII * MII utility commands
998 CONFIG_CMD_MTDPARTS * MTD partition support
999 CONFIG_CMD_NAND * NAND support
1000 CONFIG_CMD_NET bootp, tftpboot, rarpboot
1001 CONFIG_CMD_NFS NFS support
1002 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands
1003 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command
1004 CONFIG_CMD_PCI * pciinfo
1005 CONFIG_CMD_PCMCIA * PCMCIA support
1006 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network
1008 CONFIG_CMD_PORTIO * Port I/O
1009 CONFIG_CMD_READ * Read raw data from partition
1010 CONFIG_CMD_REGINFO * Register dump
1011 CONFIG_CMD_RUN run command in env variable
1012 CONFIG_CMD_SANDBOX * sb command to access sandbox features
1013 CONFIG_CMD_SAVES * save S record dump
1014 CONFIG_CMD_SCSI * SCSI Support
1015 CONFIG_CMD_SDRAM * print SDRAM configuration information
1016 (requires CONFIG_CMD_I2C)
1017 CONFIG_CMD_SETGETDCR Support for DCR Register access
1019 CONFIG_CMD_SF * Read/write/erase SPI NOR flash
1020 CONFIG_CMD_SHA1SUM * print sha1 memory digest
1021 (requires CONFIG_CMD_MEMORY)
1022 CONFIG_CMD_SOFTSWITCH * Soft switch setting command for BF60x
1023 CONFIG_CMD_SOURCE "source" command Support
1024 CONFIG_CMD_SPI * SPI serial bus support
1025 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode
1026 CONFIG_CMD_TFTPPUT * TFTP put command (upload)
1027 CONFIG_CMD_TIME * run command and report execution time (ARM specific)
1028 CONFIG_CMD_TIMER * access to the system tick timer
1029 CONFIG_CMD_USB * USB support
1030 CONFIG_CMD_CDP * Cisco Discover Protocol support
1031 CONFIG_CMD_MFSL * Microblaze FSL support
1032 CONFIG_CMD_XIMG Load part of Multi Image
1033 CONFIG_CMD_UUID * Generate random UUID or GUID string
1035 EXAMPLE: If you want all functions except of network
1036 support you can write:
1038 #include "config_cmd_all.h"
1039 #undef CONFIG_CMD_NET
1042 fdt (flattened device tree) command: CONFIG_OF_LIBFDT
1044 Note: Don't enable the "icache" and "dcache" commands
1045 (configuration option CONFIG_CMD_CACHE) unless you know
1046 what you (and your U-Boot users) are doing. Data
1047 cache cannot be enabled on systems like the 8xx or
1048 8260 (where accesses to the IMMR region must be
1049 uncached), and it cannot be disabled on all other
1050 systems where we (mis-) use the data cache to hold an
1051 initial stack and some data.
1054 XXX - this list needs to get updated!
1056 - Regular expression support:
1058 If this variable is defined, U-Boot is linked against
1059 the SLRE (Super Light Regular Expression) library,
1060 which adds regex support to some commands, as for
1061 example "env grep" and "setexpr".
1065 If this variable is defined, U-Boot will use a device tree
1066 to configure its devices, instead of relying on statically
1067 compiled #defines in the board file. This option is
1068 experimental and only available on a few boards. The device
1069 tree is available in the global data as gd->fdt_blob.
1071 U-Boot needs to get its device tree from somewhere. This can
1072 be done using one of the two options below:
1075 If this variable is defined, U-Boot will embed a device tree
1076 binary in its image. This device tree file should be in the
1077 board directory and called <soc>-<board>.dts. The binary file
1078 is then picked up in board_init_f() and made available through
1079 the global data structure as gd->blob.
1082 If this variable is defined, U-Boot will build a device tree
1083 binary. It will be called u-boot.dtb. Architecture-specific
1084 code will locate it at run-time. Generally this works by:
1086 cat u-boot.bin u-boot.dtb >image.bin
1088 and in fact, U-Boot does this for you, creating a file called
1089 u-boot-dtb.bin which is useful in the common case. You can
1090 still use the individual files if you need something more
1095 If this variable is defined, it enables watchdog
1096 support for the SoC. There must be support in the SoC
1097 specific code for a watchdog. For the 8xx and 8260
1098 CPUs, the SIU Watchdog feature is enabled in the SYPCR
1099 register. When supported for a specific SoC is
1100 available, then no further board specific code should
1101 be needed to use it.
1104 When using a watchdog circuitry external to the used
1105 SoC, then define this variable and provide board
1106 specific code for the "hw_watchdog_reset" function.
1109 CONFIG_VERSION_VARIABLE
1110 If this variable is defined, an environment variable
1111 named "ver" is created by U-Boot showing the U-Boot
1112 version as printed by the "version" command.
1113 Any change to this variable will be reverted at the
1118 When CONFIG_CMD_DATE is selected, the type of the RTC
1119 has to be selected, too. Define exactly one of the
1122 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
1123 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
1124 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC
1125 CONFIG_RTC_MC146818 - use MC146818 RTC
1126 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
1127 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
1128 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
1129 CONFIG_RTC_DS164x - use Dallas DS164x RTC
1130 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
1131 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
1132 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
1133 CONFIG_SYS_RV3029_TCR - enable trickle charger on
1136 Note that if the RTC uses I2C, then the I2C interface
1137 must also be configured. See I2C Support, below.
1140 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
1142 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
1143 chip-ngpio pairs that tell the PCA953X driver the number of
1144 pins supported by a particular chip.
1146 Note that if the GPIO device uses I2C, then the I2C interface
1147 must also be configured. See I2C Support, below.
1149 - Timestamp Support:
1151 When CONFIG_TIMESTAMP is selected, the timestamp
1152 (date and time) of an image is printed by image
1153 commands like bootm or iminfo. This option is
1154 automatically enabled when you select CONFIG_CMD_DATE .
1156 - Partition Labels (disklabels) Supported:
1157 Zero or more of the following:
1158 CONFIG_MAC_PARTITION Apple's MacOS partition table.
1159 CONFIG_DOS_PARTITION MS Dos partition table, traditional on the
1160 Intel architecture, USB sticks, etc.
1161 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc.
1162 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the
1163 bootloader. Note 2TB partition limit; see
1165 CONFIG_MTD_PARTITIONS Memory Technology Device partition table.
1167 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or
1168 CONFIG_CMD_SCSI) you must configure support for at
1169 least one non-MTD partition type as well.
1172 CONFIG_IDE_RESET_ROUTINE - this is defined in several
1173 board configurations files but used nowhere!
1175 CONFIG_IDE_RESET - is this is defined, IDE Reset will
1176 be performed by calling the function
1177 ide_set_reset(int reset)
1178 which has to be defined in a board specific file
1183 Set this to enable ATAPI support.
1188 Set this to enable support for disks larger than 137GB
1189 Also look at CONFIG_SYS_64BIT_LBA.
1190 Whithout these , LBA48 support uses 32bit variables and will 'only'
1191 support disks up to 2.1TB.
1193 CONFIG_SYS_64BIT_LBA:
1194 When enabled, makes the IDE subsystem use 64bit sector addresses.
1198 At the moment only there is only support for the
1199 SYM53C8XX SCSI controller; define
1200 CONFIG_SCSI_SYM53C8XX to enable it.
1202 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
1203 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
1204 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
1205 maximum numbers of LUNs, SCSI ID's and target
1207 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
1209 The environment variable 'scsidevs' is set to the number of
1210 SCSI devices found during the last scan.
1212 - NETWORK Support (PCI):
1214 Support for Intel 8254x/8257x gigabit chips.
1217 Utility code for direct access to the SPI bus on Intel 8257x.
1218 This does not do anything useful unless you set at least one
1219 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC.
1221 CONFIG_E1000_SPI_GENERIC
1222 Allow generic access to the SPI bus on the Intel 8257x, for
1223 example with the "sspi" command.
1226 Management command for E1000 devices. When used on devices
1227 with SPI support you can reprogram the EEPROM from U-Boot.
1229 CONFIG_E1000_FALLBACK_MAC
1230 default MAC for empty EEPROM after production.
1233 Support for Intel 82557/82559/82559ER chips.
1234 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
1235 write routine for first time initialisation.
1238 Support for Digital 2114x chips.
1239 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
1240 modem chip initialisation (KS8761/QS6611).
1243 Support for National dp83815 chips.
1246 Support for National dp8382[01] gigabit chips.
1248 - NETWORK Support (other):
1250 CONFIG_DRIVER_AT91EMAC
1251 Support for AT91RM9200 EMAC.
1254 Define this to use reduced MII inteface
1256 CONFIG_DRIVER_AT91EMAC_QUIET
1257 If this defined, the driver is quiet.
1258 The driver doen't show link status messages.
1260 CONFIG_CALXEDA_XGMAC
1261 Support for the Calxeda XGMAC device
1264 Support for SMSC's LAN91C96 chips.
1266 CONFIG_LAN91C96_BASE
1267 Define this to hold the physical address
1268 of the LAN91C96's I/O space
1270 CONFIG_LAN91C96_USE_32_BIT
1271 Define this to enable 32 bit addressing
1274 Support for SMSC's LAN91C111 chip
1276 CONFIG_SMC91111_BASE
1277 Define this to hold the physical address
1278 of the device (I/O space)
1280 CONFIG_SMC_USE_32_BIT
1281 Define this if data bus is 32 bits
1283 CONFIG_SMC_USE_IOFUNCS
1284 Define this to use i/o functions instead of macros
1285 (some hardware wont work with macros)
1287 CONFIG_DRIVER_TI_EMAC
1288 Support for davinci emac
1290 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT
1291 Define this if you have more then 3 PHYs.
1294 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
1296 CONFIG_FTGMAC100_EGIGA
1297 Define this to use GE link update with gigabit PHY.
1298 Define this if FTGMAC100 is connected to gigabit PHY.
1299 If your system has 10/100 PHY only, it might not occur
1300 wrong behavior. Because PHY usually return timeout or
1301 useless data when polling gigabit status and gigabit
1302 control registers. This behavior won't affect the
1303 correctnessof 10/100 link speed update.
1306 Support for SMSC's LAN911x and LAN921x chips
1309 Define this to hold the physical address
1310 of the device (I/O space)
1312 CONFIG_SMC911X_32_BIT
1313 Define this if data bus is 32 bits
1315 CONFIG_SMC911X_16_BIT
1316 Define this if data bus is 16 bits. If your processor
1317 automatically converts one 32 bit word to two 16 bit
1318 words you may also try CONFIG_SMC911X_32_BIT.
1321 Support for Renesas on-chip Ethernet controller
1323 CONFIG_SH_ETHER_USE_PORT
1324 Define the number of ports to be used
1326 CONFIG_SH_ETHER_PHY_ADDR
1327 Define the ETH PHY's address
1329 CONFIG_SH_ETHER_CACHE_WRITEBACK
1330 If this option is set, the driver enables cache flush.
1334 Support TPM devices.
1337 Support for i2c bus TPM devices. Only one device
1338 per system is supported at this time.
1340 CONFIG_TPM_TIS_I2C_BUS_NUMBER
1341 Define the the i2c bus number for the TPM device
1343 CONFIG_TPM_TIS_I2C_SLAVE_ADDRESS
1344 Define the TPM's address on the i2c bus
1346 CONFIG_TPM_TIS_I2C_BURST_LIMITATION
1347 Define the burst count bytes upper limit
1349 CONFIG_TPM_ATMEL_TWI
1350 Support for Atmel TWI TPM device. Requires I2C support.
1353 Support for generic parallel port TPM devices. Only one device
1354 per system is supported at this time.
1356 CONFIG_TPM_TIS_BASE_ADDRESS
1357 Base address where the generic TPM device is mapped
1358 to. Contemporary x86 systems usually map it at
1362 Add tpm monitor functions.
1363 Requires CONFIG_TPM. If CONFIG_TPM_AUTH_SESSIONS is set, also
1364 provides monitor access to authorized functions.
1367 Define this to enable the TPM support library which provides
1368 functional interfaces to some TPM commands.
1369 Requires support for a TPM device.
1371 CONFIG_TPM_AUTH_SESSIONS
1372 Define this to enable authorized functions in the TPM library.
1373 Requires CONFIG_TPM and CONFIG_SHA1.
1376 At the moment only the UHCI host controller is
1377 supported (PIP405, MIP405, MPC5200); define
1378 CONFIG_USB_UHCI to enable it.
1379 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
1380 and define CONFIG_USB_STORAGE to enable the USB
1383 Supported are USB Keyboards and USB Floppy drives
1385 MPC5200 USB requires additional defines:
1387 for 528 MHz Clock: 0x0001bbbb
1391 for differential drivers: 0x00001000
1392 for single ended drivers: 0x00005000
1393 for differential drivers on PSC3: 0x00000100
1394 for single ended drivers on PSC3: 0x00004100
1395 CONFIG_SYS_USB_EVENT_POLL
1396 May be defined to allow interrupt polling
1397 instead of using asynchronous interrupts
1399 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the
1400 txfilltuning field in the EHCI controller on reset.
1402 CONFIG_USB_HUB_MIN_POWER_ON_DELAY defines the minimum
1403 interval for usb hub power-on delay.(minimum 100msec)
1406 Define the below if you wish to use the USB console.
1407 Once firmware is rebuilt from a serial console issue the
1408 command "setenv stdin usbtty; setenv stdout usbtty" and
1409 attach your USB cable. The Unix command "dmesg" should print
1410 it has found a new device. The environment variable usbtty
1411 can be set to gserial or cdc_acm to enable your device to
1412 appear to a USB host as a Linux gserial device or a
1413 Common Device Class Abstract Control Model serial device.
1414 If you select usbtty = gserial you should be able to enumerate
1416 # modprobe usbserial vendor=0xVendorID product=0xProductID
1417 else if using cdc_acm, simply setting the environment
1418 variable usbtty to be cdc_acm should suffice. The following
1419 might be defined in YourBoardName.h
1422 Define this to build a UDC device
1425 Define this to have a tty type of device available to
1426 talk to the UDC device
1429 Define this to enable the high speed support for usb
1430 device and usbtty. If this feature is enabled, a routine
1431 int is_usbd_high_speed(void)
1432 also needs to be defined by the driver to dynamically poll
1433 whether the enumeration has succeded at high speed or full
1436 CONFIG_SYS_CONSOLE_IS_IN_ENV
1437 Define this if you want stdin, stdout &/or stderr to
1441 CONFIG_SYS_USB_EXTC_CLK 0xBLAH
1442 Derive USB clock from external clock "blah"
1443 - CONFIG_SYS_USB_EXTC_CLK 0x02
1445 CONFIG_SYS_USB_BRG_CLK 0xBLAH
1446 Derive USB clock from brgclk
1447 - CONFIG_SYS_USB_BRG_CLK 0x04
1449 If you have a USB-IF assigned VendorID then you may wish to
1450 define your own vendor specific values either in BoardName.h
1451 or directly in usbd_vendor_info.h. If you don't define
1452 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
1453 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
1454 should pretend to be a Linux device to it's target host.
1456 CONFIG_USBD_MANUFACTURER
1457 Define this string as the name of your company for
1458 - CONFIG_USBD_MANUFACTURER "my company"
1460 CONFIG_USBD_PRODUCT_NAME
1461 Define this string as the name of your product
1462 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
1464 CONFIG_USBD_VENDORID
1465 Define this as your assigned Vendor ID from the USB
1466 Implementors Forum. This *must* be a genuine Vendor ID
1467 to avoid polluting the USB namespace.
1468 - CONFIG_USBD_VENDORID 0xFFFF
1470 CONFIG_USBD_PRODUCTID
1471 Define this as the unique Product ID
1473 - CONFIG_USBD_PRODUCTID 0xFFFF
1475 Some USB device drivers may need to check USB cable attachment.
1476 In this case you can enable following config in BoardName.h:
1477 CONFIG_USB_CABLE_CHECK
1478 This enables function definition:
1479 - usb_cable_connected() in include/usb.h
1480 Implementation of this function is board-specific.
1482 - ULPI Layer Support:
1483 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via
1484 the generic ULPI layer. The generic layer accesses the ULPI PHY
1485 via the platform viewport, so you need both the genric layer and
1486 the viewport enabled. Currently only Chipidea/ARC based
1487 viewport is supported.
1488 To enable the ULPI layer support, define CONFIG_USB_ULPI and
1489 CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
1490 If your ULPI phy needs a different reference clock than the
1491 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to
1492 the appropriate value in Hz.
1495 The MMC controller on the Intel PXA is supported. To
1496 enable this define CONFIG_MMC. The MMC can be
1497 accessed from the boot prompt by mapping the device
1498 to physical memory similar to flash. Command line is
1499 enabled with CONFIG_CMD_MMC. The MMC driver also works with
1500 the FAT fs. This is enabled with CONFIG_CMD_FAT.
1503 Support for Renesas on-chip MMCIF controller
1505 CONFIG_SH_MMCIF_ADDR
1506 Define the base address of MMCIF registers
1509 Define the clock frequency for MMCIF
1511 - USB Device Firmware Update (DFU) class support:
1513 This enables the USB portion of the DFU USB class
1516 This enables the command "dfu" which is used to have
1517 U-Boot create a DFU class device via USB. This command
1518 requires that the "dfu_alt_info" environment variable be
1519 set and define the alt settings to expose to the host.
1522 This enables support for exposing (e)MMC devices via DFU.
1525 This enables support for exposing NAND devices via DFU.
1528 This enables support for exposing RAM via DFU.
1529 Note: DFU spec refer to non-volatile memory usage, but
1530 allow usages beyond the scope of spec - here RAM usage,
1531 one that would help mostly the developer.
1533 CONFIG_SYS_DFU_DATA_BUF_SIZE
1534 Dfu transfer uses a buffer before writing data to the
1535 raw storage device. Make the size (in bytes) of this buffer
1536 configurable. The size of this buffer is also configurable
1537 through the "dfu_bufsiz" environment variable.
1539 CONFIG_SYS_DFU_MAX_FILE_SIZE
1540 When updating files rather than the raw storage device,
1541 we use a static buffer to copy the file into and then write
1542 the buffer once we've been given the whole file. Define
1543 this to the maximum filesize (in bytes) for the buffer.
1544 Default is 4 MiB if undefined.
1546 DFU_DEFAULT_POLL_TIMEOUT
1547 Poll timeout [ms], is the timeout a device can send to the
1548 host. The host must wait for this timeout before sending
1549 a subsequent DFU_GET_STATUS request to the device.
1551 DFU_MANIFEST_POLL_TIMEOUT
1552 Poll timeout [ms], which the device sends to the host when
1553 entering dfuMANIFEST state. Host waits this timeout, before
1554 sending again an USB request to the device.
1556 - Journaling Flash filesystem support:
1557 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
1558 CONFIG_JFFS2_NAND_DEV
1559 Define these for a default partition on a NAND device
1561 CONFIG_SYS_JFFS2_FIRST_SECTOR,
1562 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
1563 Define these for a default partition on a NOR device
1565 CONFIG_SYS_JFFS_CUSTOM_PART
1566 Define this to create an own partition. You have to provide a
1567 function struct part_info* jffs2_part_info(int part_num)
1569 If you define only one JFFS2 partition you may also want to
1570 #define CONFIG_SYS_JFFS_SINGLE_PART 1
1571 to disable the command chpart. This is the default when you
1572 have not defined a custom partition
1574 - FAT(File Allocation Table) filesystem write function support:
1577 Define this to enable support for saving memory data as a
1578 file in FAT formatted partition.
1580 This will also enable the command "fatwrite" enabling the
1581 user to write files to FAT.
1583 CBFS (Coreboot Filesystem) support
1586 Define this to enable support for reading from a Coreboot
1587 filesystem. Available commands are cbfsinit, cbfsinfo, cbfsls
1593 Define this to enable standard (PC-Style) keyboard
1597 Standard PC keyboard driver with US (is default) and
1598 GERMAN key layout (switch via environment 'keymap=de') support.
1599 Export function i8042_kbd_init, i8042_tstc and i8042_getc
1600 for cfb_console. Supports cursor blinking.
1603 Enables a Chrome OS keyboard using the CROS_EC interface.
1604 This uses CROS_EC to communicate with a second microcontroller
1605 which provides key scans on request.
1610 Define this to enable video support (for output to
1613 CONFIG_VIDEO_CT69000
1615 Enable Chips & Technologies 69000 Video chip
1617 CONFIG_VIDEO_SMI_LYNXEM
1618 Enable Silicon Motion SMI 712/710/810 Video chip. The
1619 video output is selected via environment 'videoout'
1620 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
1623 For the CT69000 and SMI_LYNXEM drivers, videomode is
1624 selected via environment 'videomode'. Two different ways
1626 - "videomode=num" 'num' is a standard LiLo mode numbers.
1627 Following standard modes are supported (* is default):
1629 Colors 640x480 800x600 1024x768 1152x864 1280x1024
1630 -------------+---------------------------------------------
1631 8 bits | 0x301* 0x303 0x305 0x161 0x307
1632 15 bits | 0x310 0x313 0x316 0x162 0x319
1633 16 bits | 0x311 0x314 0x317 0x163 0x31A
1634 24 bits | 0x312 0x315 0x318 ? 0x31B
1635 -------------+---------------------------------------------
1636 (i.e. setenv videomode 317; saveenv; reset;)
1638 - "videomode=bootargs" all the video parameters are parsed
1639 from the bootargs. (See drivers/video/videomodes.c)
1642 CONFIG_VIDEO_SED13806
1643 Enable Epson SED13806 driver. This driver supports 8bpp
1644 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
1645 or CONFIG_VIDEO_SED13806_16BPP
1648 Enable the Freescale DIU video driver. Reference boards for
1649 SOCs that have a DIU should define this macro to enable DIU
1650 support, and should also define these other macros:
1656 CONFIG_VIDEO_SW_CURSOR
1657 CONFIG_VGA_AS_SINGLE_DEVICE
1659 CONFIG_VIDEO_BMP_LOGO
1661 The DIU driver will look for the 'video-mode' environment
1662 variable, and if defined, enable the DIU as a console during
1663 boot. See the documentation file README.video for a
1664 description of this variable.
1668 Enable the VGA video / BIOS for x86. The alternative if you
1669 are using coreboot is to use the coreboot frame buffer
1676 Define this to enable a custom keyboard support.
1677 This simply calls drv_keyboard_init() which must be
1678 defined in your board-specific files.
1679 The only board using this so far is RBC823.
1681 - LCD Support: CONFIG_LCD
1683 Define this to enable LCD support (for output to LCD
1684 display); also select one of the supported displays
1685 by defining one of these:
1689 HITACHI TX09D70VM1CCA, 3.5", 240x320.
1691 CONFIG_NEC_NL6448AC33:
1693 NEC NL6448AC33-18. Active, color, single scan.
1695 CONFIG_NEC_NL6448BC20
1697 NEC NL6448BC20-08. 6.5", 640x480.
1698 Active, color, single scan.
1700 CONFIG_NEC_NL6448BC33_54
1702 NEC NL6448BC33-54. 10.4", 640x480.
1703 Active, color, single scan.
1707 Sharp 320x240. Active, color, single scan.
1708 It isn't 16x9, and I am not sure what it is.
1710 CONFIG_SHARP_LQ64D341
1712 Sharp LQ64D341 display, 640x480.
1713 Active, color, single scan.
1717 HLD1045 display, 640x480.
1718 Active, color, single scan.
1722 Optrex CBL50840-2 NF-FW 99 22 M5
1724 Hitachi LMG6912RPFC-00T
1728 320x240. Black & white.
1730 Normally display is black on white background; define
1731 CONFIG_SYS_WHITE_ON_BLACK to get it inverted.
1733 CONFIG_LCD_ALIGNMENT
1735 Normally the LCD is page-aligned (tyically 4KB). If this is
1736 defined then the LCD will be aligned to this value instead.
1737 For ARM it is sometimes useful to use MMU_SECTION_SIZE
1738 here, since it is cheaper to change data cache settings on
1739 a per-section basis.
1741 CONFIG_CONSOLE_SCROLL_LINES
1743 When the console need to be scrolled, this is the number of
1744 lines to scroll by. It defaults to 1. Increasing this makes
1745 the console jump but can help speed up operation when scrolling
1750 Support drawing of RLE8-compressed bitmaps on the LCD.
1754 Enables an 'i2c edid' command which can read EDID
1755 information over I2C from an attached LCD display.
1757 - Splash Screen Support: CONFIG_SPLASH_SCREEN
1759 If this option is set, the environment is checked for
1760 a variable "splashimage". If found, the usual display
1761 of logo, copyright and system information on the LCD
1762 is suppressed and the BMP image at the address
1763 specified in "splashimage" is loaded instead. The
1764 console is redirected to the "nulldev", too. This
1765 allows for a "silent" boot where a splash screen is
1766 loaded very quickly after power-on.
1768 CONFIG_SPLASHIMAGE_GUARD
1770 If this option is set, then U-Boot will prevent the environment
1771 variable "splashimage" from being set to a problematic address
1772 (see README.displaying-bmps).
1773 This option is useful for targets where, due to alignment
1774 restrictions, an improperly aligned BMP image will cause a data
1775 abort. If you think you will not have problems with unaligned
1776 accesses (for example because your toolchain prevents them)
1777 there is no need to set this option.
1779 CONFIG_SPLASH_SCREEN_ALIGN
1781 If this option is set the splash image can be freely positioned
1782 on the screen. Environment variable "splashpos" specifies the
1783 position as "x,y". If a positive number is given it is used as
1784 number of pixel from left/top. If a negative number is given it
1785 is used as number of pixel from right/bottom. You can also
1786 specify 'm' for centering the image.
1789 setenv splashpos m,m
1790 => image at center of screen
1792 setenv splashpos 30,20
1793 => image at x = 30 and y = 20
1795 setenv splashpos -10,m
1796 => vertically centered image
1797 at x = dspWidth - bmpWidth - 9
1799 - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
1801 If this option is set, additionally to standard BMP
1802 images, gzipped BMP images can be displayed via the
1803 splashscreen support or the bmp command.
1805 - Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
1807 If this option is set, 8-bit RLE compressed BMP images
1808 can be displayed via the splashscreen support or the
1811 - Do compresssing for memory range:
1814 If this option is set, it would use zlib deflate method
1815 to compress the specified memory at its best effort.
1817 - Compression support:
1820 Enabled by default to support gzip compressed images.
1824 If this option is set, support for bzip2 compressed
1825 images is included. If not, only uncompressed and gzip
1826 compressed images are supported.
1828 NOTE: the bzip2 algorithm requires a lot of RAM, so
1829 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
1834 If this option is set, support for lzma compressed
1837 Note: The LZMA algorithm adds between 2 and 4KB of code and it
1838 requires an amount of dynamic memory that is given by the
1841 (1846 + 768 << (lc + lp)) * sizeof(uint16)
1843 Where lc and lp stand for, respectively, Literal context bits
1844 and Literal pos bits.
1846 This value is upper-bounded by 14MB in the worst case. Anyway,
1847 for a ~4MB large kernel image, we have lc=3 and lp=0 for a
1848 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is
1849 a very small buffer.
1851 Use the lzmainfo tool to determinate the lc and lp values and
1852 then calculate the amount of needed dynamic memory (ensuring
1853 the appropriate CONFIG_SYS_MALLOC_LEN value).
1857 If this option is set, support for LZO compressed images
1863 The address of PHY on MII bus.
1865 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1867 The clock frequency of the MII bus
1871 If this option is set, support for speed/duplex
1872 detection of gigabit PHY is included.
1874 CONFIG_PHY_RESET_DELAY
1876 Some PHY like Intel LXT971A need extra delay after
1877 reset before any MII register access is possible.
1878 For such PHY, set this option to the usec delay
1879 required. (minimum 300usec for LXT971A)
1881 CONFIG_PHY_CMD_DELAY (ppc4xx)
1883 Some PHY like Intel LXT971A need extra delay after
1884 command issued before MII status register can be read
1894 Define a default value for Ethernet address to use
1895 for the respective Ethernet interface, in case this
1896 is not determined automatically.
1901 Define a default value for the IP address to use for
1902 the default Ethernet interface, in case this is not
1903 determined through e.g. bootp.
1904 (Environment variable "ipaddr")
1906 - Server IP address:
1909 Defines a default value for the IP address of a TFTP
1910 server to contact when using the "tftboot" command.
1911 (Environment variable "serverip")
1913 CONFIG_KEEP_SERVERADDR
1915 Keeps the server's MAC address, in the env 'serveraddr'
1916 for passing to bootargs (like Linux's netconsole option)
1918 - Gateway IP address:
1921 Defines a default value for the IP address of the
1922 default router where packets to other networks are
1924 (Environment variable "gatewayip")
1929 Defines a default value for the subnet mask (or
1930 routing prefix) which is used to determine if an IP
1931 address belongs to the local subnet or needs to be
1932 forwarded through a router.
1933 (Environment variable "netmask")
1935 - Multicast TFTP Mode:
1938 Defines whether you want to support multicast TFTP as per
1939 rfc-2090; for example to work with atftp. Lets lots of targets
1940 tftp down the same boot image concurrently. Note: the Ethernet
1941 driver in use must provide a function: mcast() to join/leave a
1944 - BOOTP Recovery Mode:
1945 CONFIG_BOOTP_RANDOM_DELAY
1947 If you have many targets in a network that try to
1948 boot using BOOTP, you may want to avoid that all
1949 systems send out BOOTP requests at precisely the same
1950 moment (which would happen for instance at recovery
1951 from a power failure, when all systems will try to
1952 boot, thus flooding the BOOTP server. Defining
1953 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1954 inserted before sending out BOOTP requests. The
1955 following delays are inserted then:
1957 1st BOOTP request: delay 0 ... 1 sec
1958 2nd BOOTP request: delay 0 ... 2 sec
1959 3rd BOOTP request: delay 0 ... 4 sec
1961 BOOTP requests: delay 0 ... 8 sec
1963 - DHCP Advanced Options:
1964 You can fine tune the DHCP functionality by defining
1965 CONFIG_BOOTP_* symbols:
1967 CONFIG_BOOTP_SUBNETMASK
1968 CONFIG_BOOTP_GATEWAY
1969 CONFIG_BOOTP_HOSTNAME
1970 CONFIG_BOOTP_NISDOMAIN
1971 CONFIG_BOOTP_BOOTPATH
1972 CONFIG_BOOTP_BOOTFILESIZE
1975 CONFIG_BOOTP_SEND_HOSTNAME
1976 CONFIG_BOOTP_NTPSERVER
1977 CONFIG_BOOTP_TIMEOFFSET
1978 CONFIG_BOOTP_VENDOREX
1979 CONFIG_BOOTP_MAY_FAIL
1981 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
1982 environment variable, not the BOOTP server.
1984 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found
1985 after the configured retry count, the call will fail
1986 instead of starting over. This can be used to fail over
1987 to Link-local IP address configuration if the DHCP server
1990 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
1991 serverip from a DHCP server, it is possible that more
1992 than one DNS serverip is offered to the client.
1993 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1994 serverip will be stored in the additional environment
1995 variable "dnsip2". The first DNS serverip is always
1996 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
1999 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
2000 to do a dynamic update of a DNS server. To do this, they
2001 need the hostname of the DHCP requester.
2002 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
2003 of the "hostname" environment variable is passed as
2004 option 12 to the DHCP server.
2006 CONFIG_BOOTP_DHCP_REQUEST_DELAY
2008 A 32bit value in microseconds for a delay between
2009 receiving a "DHCP Offer" and sending the "DHCP Request".
2010 This fixes a problem with certain DHCP servers that don't
2011 respond 100% of the time to a "DHCP request". E.g. On an
2012 AT91RM9200 processor running at 180MHz, this delay needed
2013 to be *at least* 15,000 usec before a Windows Server 2003
2014 DHCP server would reply 100% of the time. I recommend at
2015 least 50,000 usec to be safe. The alternative is to hope
2016 that one of the retries will be successful but note that
2017 the DHCP timeout and retry process takes a longer than
2020 - Link-local IP address negotiation:
2021 Negotiate with other link-local clients on the local network
2022 for an address that doesn't require explicit configuration.
2023 This is especially useful if a DHCP server cannot be guaranteed
2024 to exist in all environments that the device must operate.
2026 See doc/README.link-local for more information.
2029 CONFIG_CDP_DEVICE_ID
2031 The device id used in CDP trigger frames.
2033 CONFIG_CDP_DEVICE_ID_PREFIX
2035 A two character string which is prefixed to the MAC address
2040 A printf format string which contains the ascii name of
2041 the port. Normally is set to "eth%d" which sets
2042 eth0 for the first Ethernet, eth1 for the second etc.
2044 CONFIG_CDP_CAPABILITIES
2046 A 32bit integer which indicates the device capabilities;
2047 0x00000010 for a normal host which does not forwards.
2051 An ascii string containing the version of the software.
2055 An ascii string containing the name of the platform.
2059 A 32bit integer sent on the trigger.
2061 CONFIG_CDP_POWER_CONSUMPTION
2063 A 16bit integer containing the power consumption of the
2064 device in .1 of milliwatts.
2066 CONFIG_CDP_APPLIANCE_VLAN_TYPE
2068 A byte containing the id of the VLAN.
2070 - Status LED: CONFIG_STATUS_LED
2072 Several configurations allow to display the current
2073 status using a LED. For instance, the LED will blink
2074 fast while running U-Boot code, stop blinking as
2075 soon as a reply to a BOOTP request was received, and
2076 start blinking slow once the Linux kernel is running
2077 (supported by a status LED driver in the Linux
2078 kernel). Defining CONFIG_STATUS_LED enables this
2084 The status LED can be connected to a GPIO pin.
2085 In such cases, the gpio_led driver can be used as a
2086 status LED backend implementation. Define CONFIG_GPIO_LED
2087 to include the gpio_led driver in the U-Boot binary.
2089 CONFIG_GPIO_LED_INVERTED_TABLE
2090 Some GPIO connected LEDs may have inverted polarity in which
2091 case the GPIO high value corresponds to LED off state and
2092 GPIO low value corresponds to LED on state.
2093 In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined
2094 with a list of GPIO LEDs that have inverted polarity.
2096 - CAN Support: CONFIG_CAN_DRIVER
2098 Defining CONFIG_CAN_DRIVER enables CAN driver support
2099 on those systems that support this (optional)
2100 feature, like the TQM8xxL modules.
2102 - I2C Support: CONFIG_SYS_I2C
2104 This enable the NEW i2c subsystem, and will allow you to use
2105 i2c commands at the u-boot command line (as long as you set
2106 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c
2107 based realtime clock chips or other i2c devices. See
2108 common/cmd_i2c.c for a description of the command line
2111 ported i2c driver to the new framework:
2112 - drivers/i2c/soft_i2c.c:
2113 - activate first bus with CONFIG_SYS_I2C_SOFT define
2114 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE
2115 for defining speed and slave address
2116 - activate second bus with I2C_SOFT_DECLARATIONS2 define
2117 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2
2118 for defining speed and slave address
2119 - activate third bus with I2C_SOFT_DECLARATIONS3 define
2120 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3
2121 for defining speed and slave address
2122 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define
2123 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4
2124 for defining speed and slave address
2126 - drivers/i2c/fsl_i2c.c:
2127 - activate i2c driver with CONFIG_SYS_I2C_FSL
2128 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register
2129 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and
2130 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first
2132 - If your board supports a second fsl i2c bus, define
2133 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset
2134 CONFIG_SYS_FSL_I2C2_SPEED for the speed and
2135 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the
2138 - drivers/i2c/tegra_i2c.c:
2139 - activate this driver with CONFIG_SYS_I2C_TEGRA
2140 - This driver adds 4 i2c buses with a fix speed from
2141 100000 and the slave addr 0!
2143 - drivers/i2c/ppc4xx_i2c.c
2144 - activate this driver with CONFIG_SYS_I2C_PPC4XX
2145 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0
2146 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1
2148 - drivers/i2c/i2c_mxc.c
2149 - activate this driver with CONFIG_SYS_I2C_MXC
2150 - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED
2151 - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE
2152 - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED
2153 - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE
2154 - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED
2155 - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE
2156 If thoses defines are not set, default value is 100000
2157 for speed, and 0 for slave.
2159 - drivers/i2c/rcar_i2c.c:
2160 - activate this driver with CONFIG_SYS_I2C_RCAR
2161 - This driver adds 4 i2c buses
2163 - CONFIG_SYS_RCAR_I2C0_BASE for setting the register channel 0
2164 - CONFIG_SYS_RCAR_I2C0_SPEED for for the speed channel 0
2165 - CONFIG_SYS_RCAR_I2C1_BASE for setting the register channel 1
2166 - CONFIG_SYS_RCAR_I2C1_SPEED for for the speed channel 1
2167 - CONFIG_SYS_RCAR_I2C2_BASE for setting the register channel 2
2168 - CONFIG_SYS_RCAR_I2C2_SPEED for for the speed channel 2
2169 - CONFIG_SYS_RCAR_I2C3_BASE for setting the register channel 3
2170 - CONFIG_SYS_RCAR_I2C3_SPEED for for the speed channel 3
2171 - CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS for number of i2c buses
2173 - drivers/i2c/sh_i2c.c:
2174 - activate this driver with CONFIG_SYS_I2C_SH
2175 - This driver adds from 2 to 5 i2c buses
2177 - CONFIG_SYS_I2C_SH_BASE0 for setting the register channel 0
2178 - CONFIG_SYS_I2C_SH_SPEED0 for for the speed channel 0
2179 - CONFIG_SYS_I2C_SH_BASE1 for setting the register channel 1
2180 - CONFIG_SYS_I2C_SH_SPEED1 for for the speed channel 1
2181 - CONFIG_SYS_I2C_SH_BASE2 for setting the register channel 2
2182 - CONFIG_SYS_I2C_SH_SPEED2 for for the speed channel 2
2183 - CONFIG_SYS_I2C_SH_BASE3 for setting the register channel 3
2184 - CONFIG_SYS_I2C_SH_SPEED3 for for the speed channel 3
2185 - CONFIG_SYS_I2C_SH_BASE4 for setting the register channel 4
2186 - CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4
2187 - CONFIG_SYS_I2C_SH_BASE5 for setting the register channel 5
2188 - CONFIG_SYS_I2C_SH_SPEED5 for for the speed channel 5
2189 - CONFIF_SYS_I2C_SH_NUM_CONTROLLERS for nummber of i2c buses
2191 - drivers/i2c/omap24xx_i2c.c
2192 - activate this driver with CONFIG_SYS_I2C_OMAP24XX
2193 - CONFIG_SYS_OMAP24_I2C_SPEED speed channel 0
2194 - CONFIG_SYS_OMAP24_I2C_SLAVE slave addr channel 0
2195 - CONFIG_SYS_OMAP24_I2C_SPEED1 speed channel 1
2196 - CONFIG_SYS_OMAP24_I2C_SLAVE1 slave addr channel 1
2197 - CONFIG_SYS_OMAP24_I2C_SPEED2 speed channel 2
2198 - CONFIG_SYS_OMAP24_I2C_SLAVE2 slave addr channel 2
2199 - CONFIG_SYS_OMAP24_I2C_SPEED3 speed channel 3
2200 - CONFIG_SYS_OMAP24_I2C_SLAVE3 slave addr channel 3
2201 - CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4
2202 - CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4
2204 - drivers/i2c/zynq_i2c.c
2205 - activate this driver with CONFIG_SYS_I2C_ZYNQ
2206 - set CONFIG_SYS_I2C_ZYNQ_SPEED for speed setting
2207 - set CONFIG_SYS_I2C_ZYNQ_SLAVE for slave addr
2209 - drivers/i2c/s3c24x0_i2c.c:
2210 - activate this driver with CONFIG_SYS_I2C_S3C24X0
2211 - This driver adds i2c buses (11 for Exynos5250, Exynos5420
2212 9 i2c buses for Exynos4 and 1 for S3C24X0 SoCs from Samsung)
2213 with a fix speed from 100000 and the slave addr 0!
2217 CONFIG_SYS_NUM_I2C_BUSES
2218 Hold the number of i2c busses you want to use. If you
2219 don't use/have i2c muxes on your i2c bus, this
2220 is equal to CONFIG_SYS_NUM_I2C_ADAPTERS, and you can
2223 CONFIG_SYS_I2C_DIRECT_BUS
2224 define this, if you don't use i2c muxes on your hardware.
2225 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can
2228 CONFIG_SYS_I2C_MAX_HOPS
2229 define how many muxes are maximal consecutively connected
2230 on one i2c bus. If you not use i2c muxes, omit this
2233 CONFIG_SYS_I2C_BUSES
2234 hold a list of busses you want to use, only used if
2235 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example
2236 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and
2237 CONFIG_SYS_NUM_I2C_BUSES = 9:
2239 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \
2240 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \
2241 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \
2242 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \
2243 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \
2244 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \
2245 {1, {I2C_NULL_HOP}}, \
2246 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \
2247 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \
2251 bus 0 on adapter 0 without a mux
2252 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1
2253 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2
2254 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3
2255 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4
2256 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5
2257 bus 6 on adapter 1 without a mux
2258 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1
2259 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2
2261 If you do not have i2c muxes on your board, omit this define.
2263 - Legacy I2C Support: CONFIG_HARD_I2C
2265 NOTE: It is intended to move drivers to CONFIG_SYS_I2C which
2266 provides the following compelling advantages:
2268 - more than one i2c adapter is usable
2269 - approved multibus support
2270 - better i2c mux support
2272 ** Please consider updating your I2C driver now. **
2274 These enable legacy I2C serial bus commands. Defining
2275 CONFIG_HARD_I2C will include the appropriate I2C driver
2276 for the selected CPU.
2278 This will allow you to use i2c commands at the u-boot
2279 command line (as long as you set CONFIG_CMD_I2C in
2280 CONFIG_COMMANDS) and communicate with i2c based realtime
2281 clock chips. See common/cmd_i2c.c for a description of the
2282 command line interface.
2284 CONFIG_HARD_I2C selects a hardware I2C controller.
2286 There are several other quantities that must also be
2287 defined when you define CONFIG_HARD_I2C.
2289 In both cases you will need to define CONFIG_SYS_I2C_SPEED
2290 to be the frequency (in Hz) at which you wish your i2c bus
2291 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie
2292 the CPU's i2c node address).
2294 Now, the u-boot i2c code for the mpc8xx
2295 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node
2296 and so its address should therefore be cleared to 0 (See,
2297 eg, MPC823e User's Manual p.16-473). So, set
2298 CONFIG_SYS_I2C_SLAVE to 0.
2300 CONFIG_SYS_I2C_INIT_MPC5XXX
2302 When a board is reset during an i2c bus transfer
2303 chips might think that the current transfer is still
2304 in progress. Reset the slave devices by sending start
2305 commands until the slave device responds.
2307 That's all that's required for CONFIG_HARD_I2C.
2309 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT)
2310 then the following macros need to be defined (examples are
2311 from include/configs/lwmon.h):
2315 (Optional). Any commands necessary to enable the I2C
2316 controller or configure ports.
2318 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
2322 (Only for MPC8260 CPU). The I/O port to use (the code
2323 assumes both bits are on the same port). Valid values
2324 are 0..3 for ports A..D.
2328 The code necessary to make the I2C data line active
2329 (driven). If the data line is open collector, this
2332 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
2336 The code necessary to make the I2C data line tri-stated
2337 (inactive). If the data line is open collector, this
2340 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
2344 Code that returns true if the I2C data line is high,
2347 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
2351 If <bit> is true, sets the I2C data line high. If it
2352 is false, it clears it (low).
2354 eg: #define I2C_SDA(bit) \
2355 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
2356 else immr->im_cpm.cp_pbdat &= ~PB_SDA
2360 If <bit> is true, sets the I2C clock line high. If it
2361 is false, it clears it (low).
2363 eg: #define I2C_SCL(bit) \
2364 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
2365 else immr->im_cpm.cp_pbdat &= ~PB_SCL
2369 This delay is invoked four times per clock cycle so this
2370 controls the rate of data transfer. The data rate thus
2371 is 1 / (I2C_DELAY * 4). Often defined to be something
2374 #define I2C_DELAY udelay(2)
2376 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
2378 If your arch supports the generic GPIO framework (asm/gpio.h),
2379 then you may alternatively define the two GPIOs that are to be
2380 used as SCL / SDA. Any of the previous I2C_xxx macros will
2381 have GPIO-based defaults assigned to them as appropriate.
2383 You should define these to the GPIO value as given directly to
2384 the generic GPIO functions.
2386 CONFIG_SYS_I2C_INIT_BOARD
2388 When a board is reset during an i2c bus transfer
2389 chips might think that the current transfer is still
2390 in progress. On some boards it is possible to access
2391 the i2c SCLK line directly, either by using the
2392 processor pin as a GPIO or by having a second pin
2393 connected to the bus. If this option is defined a
2394 custom i2c_init_board() routine in boards/xxx/board.c
2395 is run early in the boot sequence.
2397 CONFIG_SYS_I2C_BOARD_LATE_INIT
2399 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is
2400 defined a custom i2c_board_late_init() routine in
2401 boards/xxx/board.c is run AFTER the operations in i2c_init()
2402 is completed. This callpoint can be used to unreset i2c bus
2403 using CPU i2c controller register accesses for CPUs whose i2c
2404 controller provide such a method. It is called at the end of
2405 i2c_init() to allow i2c_init operations to setup the i2c bus
2406 controller on the CPU (e.g. setting bus speed & slave address).
2408 CONFIG_I2CFAST (PPC405GP|PPC405EP only)
2410 This option enables configuration of bi_iic_fast[] flags
2411 in u-boot bd_info structure based on u-boot environment
2412 variable "i2cfast". (see also i2cfast)
2414 CONFIG_I2C_MULTI_BUS
2416 This option allows the use of multiple I2C buses, each of which
2417 must have a controller. At any point in time, only one bus is
2418 active. To switch to a different bus, use the 'i2c dev' command.
2419 Note that bus numbering is zero-based.
2421 CONFIG_SYS_I2C_NOPROBES
2423 This option specifies a list of I2C devices that will be skipped
2424 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
2425 is set, specify a list of bus-device pairs. Otherwise, specify
2426 a 1D array of device addresses
2429 #undef CONFIG_I2C_MULTI_BUS
2430 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
2432 will skip addresses 0x50 and 0x68 on a board with one I2C bus
2434 #define CONFIG_I2C_MULTI_BUS
2435 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
2437 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
2439 CONFIG_SYS_SPD_BUS_NUM
2441 If defined, then this indicates the I2C bus number for DDR SPD.
2442 If not defined, then U-Boot assumes that SPD is on I2C bus 0.
2444 CONFIG_SYS_RTC_BUS_NUM
2446 If defined, then this indicates the I2C bus number for the RTC.
2447 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
2449 CONFIG_SYS_DTT_BUS_NUM
2451 If defined, then this indicates the I2C bus number for the DTT.
2452 If not defined, then U-Boot assumes that DTT is on I2C bus 0.
2454 CONFIG_SYS_I2C_DTT_ADDR:
2456 If defined, specifies the I2C address of the DTT device.
2457 If not defined, then U-Boot uses predefined value for
2458 specified DTT device.
2460 CONFIG_SOFT_I2C_READ_REPEATED_START
2462 defining this will force the i2c_read() function in
2463 the soft_i2c driver to perform an I2C repeated start
2464 between writing the address pointer and reading the
2465 data. If this define is omitted the default behaviour
2466 of doing a stop-start sequence will be used. Most I2C
2467 devices can use either method, but some require one or
2470 - SPI Support: CONFIG_SPI
2472 Enables SPI driver (so far only tested with
2473 SPI EEPROM, also an instance works with Crystal A/D and
2474 D/As on the SACSng board)
2478 Enables the driver for SPI controller on SuperH. Currently
2479 only SH7757 is supported.
2483 Enables extended (16-bit) SPI EEPROM addressing.
2484 (symmetrical to CONFIG_I2C_X)
2488 Enables a software (bit-bang) SPI driver rather than
2489 using hardware support. This is a general purpose
2490 driver that only requires three general I/O port pins
2491 (two outputs, one input) to function. If this is
2492 defined, the board configuration must define several
2493 SPI configuration items (port pins to use, etc). For
2494 an example, see include/configs/sacsng.h.
2498 Enables a hardware SPI driver for general-purpose reads
2499 and writes. As with CONFIG_SOFT_SPI, the board configuration
2500 must define a list of chip-select function pointers.
2501 Currently supported on some MPC8xxx processors. For an
2502 example, see include/configs/mpc8349emds.h.
2506 Enables the driver for the SPI controllers on i.MX and MXC
2507 SoCs. Currently i.MX31/35/51 are supported.
2509 - FPGA Support: CONFIG_FPGA
2511 Enables FPGA subsystem.
2513 CONFIG_FPGA_<vendor>
2515 Enables support for specific chip vendors.
2518 CONFIG_FPGA_<family>
2520 Enables support for FPGA family.
2521 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
2525 Specify the number of FPGA devices to support.
2527 CONFIG_SYS_FPGA_PROG_FEEDBACK
2529 Enable printing of hash marks during FPGA configuration.
2531 CONFIG_SYS_FPGA_CHECK_BUSY
2533 Enable checks on FPGA configuration interface busy
2534 status by the configuration function. This option
2535 will require a board or device specific function to
2540 If defined, a function that provides delays in the FPGA
2541 configuration driver.
2543 CONFIG_SYS_FPGA_CHECK_CTRLC
2544 Allow Control-C to interrupt FPGA configuration
2546 CONFIG_SYS_FPGA_CHECK_ERROR
2548 Check for configuration errors during FPGA bitfile
2549 loading. For example, abort during Virtex II
2550 configuration if the INIT_B line goes low (which
2551 indicated a CRC error).
2553 CONFIG_SYS_FPGA_WAIT_INIT
2555 Maximum time to wait for the INIT_B line to deassert
2556 after PROB_B has been deasserted during a Virtex II
2557 FPGA configuration sequence. The default time is 500
2560 CONFIG_SYS_FPGA_WAIT_BUSY
2562 Maximum time to wait for BUSY to deassert during
2563 Virtex II FPGA configuration. The default is 5 ms.
2565 CONFIG_SYS_FPGA_WAIT_CONFIG
2567 Time to wait after FPGA configuration. The default is
2570 - Configuration Management:
2573 If defined, this string will be added to the U-Boot
2574 version information (U_BOOT_VERSION)
2576 - Vendor Parameter Protection:
2578 U-Boot considers the values of the environment
2579 variables "serial#" (Board Serial Number) and
2580 "ethaddr" (Ethernet Address) to be parameters that
2581 are set once by the board vendor / manufacturer, and
2582 protects these variables from casual modification by
2583 the user. Once set, these variables are read-only,
2584 and write or delete attempts are rejected. You can
2585 change this behaviour:
2587 If CONFIG_ENV_OVERWRITE is #defined in your config
2588 file, the write protection for vendor parameters is
2589 completely disabled. Anybody can change or delete
2592 Alternatively, if you #define _both_ CONFIG_ETHADDR
2593 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
2594 Ethernet address is installed in the environment,
2595 which can be changed exactly ONCE by the user. [The
2596 serial# is unaffected by this, i. e. it remains
2599 The same can be accomplished in a more flexible way
2600 for any variable by configuring the type of access
2601 to allow for those variables in the ".flags" variable
2602 or define CONFIG_ENV_FLAGS_LIST_STATIC.
2607 Define this variable to enable the reservation of
2608 "protected RAM", i. e. RAM which is not overwritten
2609 by U-Boot. Define CONFIG_PRAM to hold the number of
2610 kB you want to reserve for pRAM. You can overwrite
2611 this default value by defining an environment
2612 variable "pram" to the number of kB you want to
2613 reserve. Note that the board info structure will
2614 still show the full amount of RAM. If pRAM is
2615 reserved, a new environment variable "mem" will
2616 automatically be defined to hold the amount of
2617 remaining RAM in a form that can be passed as boot
2618 argument to Linux, for instance like that:
2620 setenv bootargs ... mem=\${mem}
2623 This way you can tell Linux not to use this memory,
2624 either, which results in a memory region that will
2625 not be affected by reboots.
2627 *WARNING* If your board configuration uses automatic
2628 detection of the RAM size, you must make sure that
2629 this memory test is non-destructive. So far, the
2630 following board configurations are known to be
2633 IVMS8, IVML24, SPD8xx, TQM8xxL,
2634 HERMES, IP860, RPXlite, LWMON,
2637 - Access to physical memory region (> 4GB)
2638 Some basic support is provided for operations on memory not
2639 normally accessible to U-Boot - e.g. some architectures
2640 support access to more than 4GB of memory on 32-bit
2641 machines using physical address extension or similar.
2642 Define CONFIG_PHYSMEM to access this basic support, which
2643 currently only supports clearing the memory.
2648 Define this variable to stop the system in case of a
2649 fatal error, so that you have to reset it manually.
2650 This is probably NOT a good idea for an embedded
2651 system where you want the system to reboot
2652 automatically as fast as possible, but it may be
2653 useful during development since you can try to debug
2654 the conditions that lead to the situation.
2656 CONFIG_NET_RETRY_COUNT
2658 This variable defines the number of retries for
2659 network operations like ARP, RARP, TFTP, or BOOTP
2660 before giving up the operation. If not defined, a
2661 default value of 5 is used.
2665 Timeout waiting for an ARP reply in milliseconds.
2669 Timeout in milliseconds used in NFS protocol.
2670 If you encounter "ERROR: Cannot umount" in nfs command,
2671 try longer timeout such as
2672 #define CONFIG_NFS_TIMEOUT 10000UL
2674 - Command Interpreter:
2675 CONFIG_AUTO_COMPLETE
2677 Enable auto completion of commands using TAB.
2679 Note that this feature has NOT been implemented yet
2680 for the "hush" shell.
2683 CONFIG_SYS_HUSH_PARSER
2685 Define this variable to enable the "hush" shell (from
2686 Busybox) as command line interpreter, thus enabling
2687 powerful command line syntax like
2688 if...then...else...fi conditionals or `&&' and '||'
2689 constructs ("shell scripts").
2691 If undefined, you get the old, much simpler behaviour
2692 with a somewhat smaller memory footprint.
2695 CONFIG_SYS_PROMPT_HUSH_PS2
2697 This defines the secondary prompt string, which is
2698 printed when the command interpreter needs more input
2699 to complete a command. Usually "> ".
2703 In the current implementation, the local variables
2704 space and global environment variables space are
2705 separated. Local variables are those you define by
2706 simply typing `name=value'. To access a local
2707 variable later on, you have write `$name' or
2708 `${name}'; to execute the contents of a variable
2709 directly type `$name' at the command prompt.
2711 Global environment variables are those you use
2712 setenv/printenv to work with. To run a command stored
2713 in such a variable, you need to use the run command,
2714 and you must not use the '$' sign to access them.
2716 To store commands and special characters in a
2717 variable, please use double quotation marks
2718 surrounding the whole text of the variable, instead
2719 of the backslashes before semicolons and special
2722 - Commandline Editing and History:
2723 CONFIG_CMDLINE_EDITING
2725 Enable editing and History functions for interactive
2726 commandline input operations
2728 - Default Environment:
2729 CONFIG_EXTRA_ENV_SETTINGS
2731 Define this to contain any number of null terminated
2732 strings (variable = value pairs) that will be part of
2733 the default environment compiled into the boot image.
2735 For example, place something like this in your
2736 board's config file:
2738 #define CONFIG_EXTRA_ENV_SETTINGS \
2742 Warning: This method is based on knowledge about the
2743 internal format how the environment is stored by the
2744 U-Boot code. This is NOT an official, exported
2745 interface! Although it is unlikely that this format
2746 will change soon, there is no guarantee either.
2747 You better know what you are doing here.
2749 Note: overly (ab)use of the default environment is
2750 discouraged. Make sure to check other ways to preset
2751 the environment like the "source" command or the
2754 CONFIG_ENV_VARS_UBOOT_CONFIG
2756 Define this in order to add variables describing the
2757 U-Boot build configuration to the default environment.
2758 These will be named arch, cpu, board, vendor, and soc.
2760 Enabling this option will cause the following to be defined:
2768 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG
2770 Define this in order to add variables describing certain
2771 run-time determined information about the hardware to the
2772 environment. These will be named board_name, board_rev.
2774 CONFIG_DELAY_ENVIRONMENT
2776 Normally the environment is loaded when the board is
2777 intialised so that it is available to U-Boot. This inhibits
2778 that so that the environment is not available until
2779 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL
2780 this is instead controlled by the value of
2781 /config/load-environment.
2783 - DataFlash Support:
2784 CONFIG_HAS_DATAFLASH
2786 Defining this option enables DataFlash features and
2787 allows to read/write in Dataflash via the standard
2790 - Serial Flash support
2793 Defining this option enables SPI flash commands
2794 'sf probe/read/write/erase/update'.
2796 Usage requires an initial 'probe' to define the serial
2797 flash parameters, followed by read/write/erase/update
2800 The following defaults may be provided by the platform
2801 to handle the common case when only a single serial
2802 flash is present on the system.
2804 CONFIG_SF_DEFAULT_BUS Bus identifier
2805 CONFIG_SF_DEFAULT_CS Chip-select
2806 CONFIG_SF_DEFAULT_MODE (see include/spi.h)
2807 CONFIG_SF_DEFAULT_SPEED in Hz
2811 Define this option to include a destructive SPI flash
2814 CONFIG_SPI_FLASH_BAR Ban/Extended Addr Reg
2816 Define this option to use the Bank addr/Extended addr
2817 support on SPI flashes which has size > 16Mbytes.
2819 CONFIG_SF_DUAL_FLASH Dual flash memories
2821 Define this option to use dual flash support where two flash
2822 memories can be connected with a given cs line.
2823 currently Xilinx Zynq qspi support these type of connections.
2825 - SystemACE Support:
2828 Adding this option adds support for Xilinx SystemACE
2829 chips attached via some sort of local bus. The address
2830 of the chip must also be defined in the
2831 CONFIG_SYS_SYSTEMACE_BASE macro. For example:
2833 #define CONFIG_SYSTEMACE
2834 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000
2836 When SystemACE support is added, the "ace" device type
2837 becomes available to the fat commands, i.e. fatls.
2839 - TFTP Fixed UDP Port:
2842 If this is defined, the environment variable tftpsrcp
2843 is used to supply the TFTP UDP source port value.
2844 If tftpsrcp isn't defined, the normal pseudo-random port
2845 number generator is used.
2847 Also, the environment variable tftpdstp is used to supply
2848 the TFTP UDP destination port value. If tftpdstp isn't
2849 defined, the normal port 69 is used.
2851 The purpose for tftpsrcp is to allow a TFTP server to
2852 blindly start the TFTP transfer using the pre-configured
2853 target IP address and UDP port. This has the effect of
2854 "punching through" the (Windows XP) firewall, allowing
2855 the remainder of the TFTP transfer to proceed normally.
2856 A better solution is to properly configure the firewall,
2857 but sometimes that is not allowed.
2862 This enables a generic 'hash' command which can produce
2863 hashes / digests from a few algorithms (e.g. SHA1, SHA256).
2867 Enable the hash verify command (hash -v). This adds to code
2870 CONFIG_SHA1 - support SHA1 hashing
2871 CONFIG_SHA256 - support SHA256 hashing
2873 Note: There is also a sha1sum command, which should perhaps
2874 be deprecated in favour of 'hash sha1'.
2876 - Freescale i.MX specific commands:
2877 CONFIG_CMD_HDMIDETECT
2878 This enables 'hdmidet' command which returns true if an
2879 HDMI monitor is detected. This command is i.MX 6 specific.
2882 This enables the 'bmode' (bootmode) command for forcing
2883 a boot from specific media.
2885 This is useful for forcing the ROM's usb downloader to
2886 activate upon a watchdog reset which is nice when iterating
2887 on U-Boot. Using the reset button or running bmode normal
2888 will set it back to normal. This command currently
2889 supports i.MX53 and i.MX6.
2894 This enables the RSA algorithm used for FIT image verification
2895 in U-Boot. See doc/uImage.FIT/signature.txt for more information.
2897 The signing part is build into mkimage regardless of this
2900 - bootcount support:
2901 CONFIG_BOOTCOUNT_LIMIT
2903 This enables the bootcounter support, see:
2904 http://www.denx.de/wiki/DULG/UBootBootCountLimit
2907 enable special bootcounter support on at91sam9xe based boards.
2909 enable special bootcounter support on blackfin based boards.
2911 enable special bootcounter support on da850 based boards.
2912 CONFIG_BOOTCOUNT_RAM
2913 enable support for the bootcounter in RAM
2914 CONFIG_BOOTCOUNT_I2C
2915 enable support for the bootcounter on an i2c (like RTC) device.
2916 CONFIG_SYS_I2C_RTC_ADDR = i2c chip address
2917 CONFIG_SYS_BOOTCOUNT_ADDR = i2c addr which is used for
2919 CONFIG_BOOTCOUNT_ALEN = address len
2921 - Show boot progress:
2922 CONFIG_SHOW_BOOT_PROGRESS
2924 Defining this option allows to add some board-
2925 specific code (calling a user-provided function
2926 "show_boot_progress(int)") that enables you to show
2927 the system's boot progress on some display (for
2928 example, some LED's) on your board. At the moment,
2929 the following checkpoints are implemented:
2931 - Detailed boot stage timing
2933 Define this option to get detailed timing of each stage
2934 of the boot process.
2936 CONFIG_BOOTSTAGE_USER_COUNT
2937 This is the number of available user bootstage records.
2938 Each time you call bootstage_mark(BOOTSTAGE_ID_ALLOC, ...)
2939 a new ID will be allocated from this stash. If you exceed
2940 the limit, recording will stop.
2942 CONFIG_BOOTSTAGE_REPORT
2943 Define this to print a report before boot, similar to this:
2945 Timer summary in microseconds:
2948 3,575,678 3,575,678 board_init_f start
2949 3,575,695 17 arch_cpu_init A9
2950 3,575,777 82 arch_cpu_init done
2951 3,659,598 83,821 board_init_r start
2952 3,910,375 250,777 main_loop
2953 29,916,167 26,005,792 bootm_start
2954 30,361,327 445,160 start_kernel
2956 CONFIG_CMD_BOOTSTAGE
2957 Add a 'bootstage' command which supports printing a report
2958 and un/stashing of bootstage data.
2960 CONFIG_BOOTSTAGE_FDT
2961 Stash the bootstage information in the FDT. A root 'bootstage'
2962 node is created with each bootstage id as a child. Each child
2963 has a 'name' property and either 'mark' containing the
2964 mark time in microsecond, or 'accum' containing the
2965 accumulated time for that bootstage id in microseconds.
2970 name = "board_init_f";
2979 Code in the Linux kernel can find this in /proc/devicetree.
2981 Legacy uImage format:
2984 1 common/cmd_bootm.c before attempting to boot an image
2985 -1 common/cmd_bootm.c Image header has bad magic number
2986 2 common/cmd_bootm.c Image header has correct magic number
2987 -2 common/cmd_bootm.c Image header has bad checksum
2988 3 common/cmd_bootm.c Image header has correct checksum
2989 -3 common/cmd_bootm.c Image data has bad checksum
2990 4 common/cmd_bootm.c Image data has correct checksum
2991 -4 common/cmd_bootm.c Image is for unsupported architecture
2992 5 common/cmd_bootm.c Architecture check OK
2993 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
2994 6 common/cmd_bootm.c Image Type check OK
2995 -6 common/cmd_bootm.c gunzip uncompression error
2996 -7 common/cmd_bootm.c Unimplemented compression type
2997 7 common/cmd_bootm.c Uncompression OK
2998 8 common/cmd_bootm.c No uncompress/copy overwrite error
2999 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
3001 9 common/image.c Start initial ramdisk verification
3002 -10 common/image.c Ramdisk header has bad magic number
3003 -11 common/image.c Ramdisk header has bad checksum
3004 10 common/image.c Ramdisk header is OK
3005 -12 common/image.c Ramdisk data has bad checksum
3006 11 common/image.c Ramdisk data has correct checksum
3007 12 common/image.c Ramdisk verification complete, start loading
3008 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
3009 13 common/image.c Start multifile image verification
3010 14 common/image.c No initial ramdisk, no multifile, continue.
3012 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
3014 -30 arch/powerpc/lib/board.c Fatal error, hang the system
3015 -31 post/post.c POST test failed, detected by post_output_backlog()
3016 -32 post/post.c POST test failed, detected by post_run_single()
3018 34 common/cmd_doc.c before loading a Image from a DOC device
3019 -35 common/cmd_doc.c Bad usage of "doc" command
3020 35 common/cmd_doc.c correct usage of "doc" command
3021 -36 common/cmd_doc.c No boot device
3022 36 common/cmd_doc.c correct boot device
3023 -37 common/cmd_doc.c Unknown Chip ID on boot device
3024 37 common/cmd_doc.c correct chip ID found, device available
3025 -38 common/cmd_doc.c Read Error on boot device
3026 38 common/cmd_doc.c reading Image header from DOC device OK
3027 -39 common/cmd_doc.c Image header has bad magic number
3028 39 common/cmd_doc.c Image header has correct magic number
3029 -40 common/cmd_doc.c Error reading Image from DOC device
3030 40 common/cmd_doc.c Image header has correct magic number
3031 41 common/cmd_ide.c before loading a Image from a IDE device
3032 -42 common/cmd_ide.c Bad usage of "ide" command
3033 42 common/cmd_ide.c correct usage of "ide" command
3034 -43 common/cmd_ide.c No boot device
3035 43 common/cmd_ide.c boot device found
3036 -44 common/cmd_ide.c Device not available
3037 44 common/cmd_ide.c Device available
3038 -45 common/cmd_ide.c wrong partition selected
3039 45 common/cmd_ide.c partition selected
3040 -46 common/cmd_ide.c Unknown partition table
3041 46 common/cmd_ide.c valid partition table found
3042 -47 common/cmd_ide.c Invalid partition type
3043 47 common/cmd_ide.c correct partition type
3044 -48 common/cmd_ide.c Error reading Image Header on boot device
3045 48 common/cmd_ide.c reading Image Header from IDE device OK
3046 -49 common/cmd_ide.c Image header has bad magic number
3047 49 common/cmd_ide.c Image header has correct magic number
3048 -50 common/cmd_ide.c Image header has bad checksum
3049 50 common/cmd_ide.c Image header has correct checksum
3050 -51 common/cmd_ide.c Error reading Image from IDE device
3051 51 common/cmd_ide.c reading Image from IDE device OK
3052 52 common/cmd_nand.c before loading a Image from a NAND device
3053 -53 common/cmd_nand.c Bad usage of "nand" command
3054 53 common/cmd_nand.c correct usage of "nand" command
3055 -54 common/cmd_nand.c No boot device
3056 54 common/cmd_nand.c boot device found
3057 -55 common/cmd_nand.c Unknown Chip ID on boot device
3058 55 common/cmd_nand.c correct chip ID found, device available
3059 -56 common/cmd_nand.c Error reading Image Header on boot device
3060 56 common/cmd_nand.c reading Image Header from NAND device OK
3061 -57 common/cmd_nand.c Image header has bad magic number
3062 57 common/cmd_nand.c Image header has correct magic number
3063 -58 common/cmd_nand.c Error reading Image from NAND device
3064 58 common/cmd_nand.c reading Image from NAND device OK
3066 -60 common/env_common.c Environment has a bad CRC, using default
3068 64 net/eth.c starting with Ethernet configuration.
3069 -64 net/eth.c no Ethernet found.
3070 65 net/eth.c Ethernet found.
3072 -80 common/cmd_net.c usage wrong
3073 80 common/cmd_net.c before calling NetLoop()
3074 -81 common/cmd_net.c some error in NetLoop() occurred
3075 81 common/cmd_net.c NetLoop() back without error
3076 -82 common/cmd_net.c size == 0 (File with size 0 loaded)
3077 82 common/cmd_net.c trying automatic boot
3078 83 common/cmd_net.c running "source" command
3079 -83 common/cmd_net.c some error in automatic boot or "source" command
3080 84 common/cmd_net.c end without errors
3085 100 common/cmd_bootm.c Kernel FIT Image has correct format
3086 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
3087 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
3088 -101 common/cmd_bootm.c Can't get configuration for kernel subimage
3089 102 common/cmd_bootm.c Kernel unit name specified
3090 -103 common/cmd_bootm.c Can't get kernel subimage node offset
3091 103 common/cmd_bootm.c Found configuration node
3092 104 common/cmd_bootm.c Got kernel subimage node offset
3093 -104 common/cmd_bootm.c Kernel subimage hash verification failed
3094 105 common/cmd_bootm.c Kernel subimage hash verification OK
3095 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
3096 106 common/cmd_bootm.c Architecture check OK
3097 -106 common/cmd_bootm.c Kernel subimage has wrong type
3098 107 common/cmd_bootm.c Kernel subimage type OK
3099 -107 common/cmd_bootm.c Can't get kernel subimage data/size
3100 108 common/cmd_bootm.c Got kernel subimage data/size
3101 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
3102 -109 common/cmd_bootm.c Can't get kernel subimage type
3103 -110 common/cmd_bootm.c Can't get kernel subimage comp
3104 -111 common/cmd_bootm.c Can't get kernel subimage os
3105 -112 common/cmd_bootm.c Can't get kernel subimage load address
3106 -113 common/cmd_bootm.c Image uncompress/copy overwrite error
3108 120 common/image.c Start initial ramdisk verification
3109 -120 common/image.c Ramdisk FIT image has incorrect format
3110 121 common/image.c Ramdisk FIT image has correct format
3111 122 common/image.c No ramdisk subimage unit name, using configuration
3112 -122 common/image.c Can't get configuration for ramdisk subimage
3113 123 common/image.c Ramdisk unit name specified
3114 -124 common/image.c Can't get ramdisk subimage node offset
3115 125 common/image.c Got ramdisk subimage node offset
3116 -125 common/image.c Ramdisk subimage hash verification failed
3117 126 common/image.c Ramdisk subimage hash verification OK
3118 -126 common/image.c Ramdisk subimage for unsupported architecture
3119 127 common/image.c Architecture check OK
3120 -127 common/image.c Can't get ramdisk subimage data/size
3121 128 common/image.c Got ramdisk subimage data/size
3122 129 common/image.c Can't get ramdisk load address
3123 -129 common/image.c Got ramdisk load address
3125 -130 common/cmd_doc.c Incorrect FIT image format
3126 131 common/cmd_doc.c FIT image format OK
3128 -140 common/cmd_ide.c Incorrect FIT image format
3129 141 common/cmd_ide.c FIT image format OK
3131 -150 common/cmd_nand.c Incorrect FIT image format
3132 151 common/cmd_nand.c FIT image format OK
3134 - FIT image support:
3136 Enable support for the FIT uImage format.
3138 CONFIG_FIT_BEST_MATCH
3139 When no configuration is explicitly selected, default to the
3140 one whose fdt's compatibility field best matches that of
3141 U-Boot itself. A match is considered "best" if it matches the
3142 most specific compatibility entry of U-Boot's fdt's root node.
3143 The order of entries in the configuration's fdt is ignored.
3145 CONFIG_FIT_SIGNATURE
3146 This option enables signature verification of FIT uImages,
3147 using a hash signed and verified using RSA. See
3148 doc/uImage.FIT/signature.txt for more details.
3150 - Standalone program support:
3151 CONFIG_STANDALONE_LOAD_ADDR
3153 This option defines a board specific value for the
3154 address where standalone program gets loaded, thus
3155 overwriting the architecture dependent default
3158 - Frame Buffer Address:
3161 Define CONFIG_FB_ADDR if you want to use specific
3162 address for frame buffer. This is typically the case
3163 when using a graphics controller has separate video
3164 memory. U-Boot will then place the frame buffer at
3165 the given address instead of dynamically reserving it
3166 in system RAM by calling lcd_setmem(), which grabs
3167 the memory for the frame buffer depending on the
3168 configured panel size.
3170 Please see board_init_f function.
3172 - Automatic software updates via TFTP server
3174 CONFIG_UPDATE_TFTP_CNT_MAX
3175 CONFIG_UPDATE_TFTP_MSEC_MAX
3177 These options enable and control the auto-update feature;
3178 for a more detailed description refer to doc/README.update.
3180 - MTD Support (mtdparts command, UBI support)
3183 Adds the MTD device infrastructure from the Linux kernel.
3184 Needed for mtdparts command support.
3186 CONFIG_MTD_PARTITIONS
3188 Adds the MTD partitioning infrastructure from the Linux
3189 kernel. Needed for UBI support.
3194 Adds commands for interacting with MTD partitions formatted
3195 with the UBI flash translation layer
3197 Requires also defining CONFIG_RBTREE
3199 CONFIG_UBI_SILENCE_MSG
3201 Make the verbose messages from UBI stop printing. This leaves
3202 warnings and errors enabled.
3207 Adds commands for interacting with UBI volumes formatted as
3208 UBIFS. UBIFS is read-only in u-boot.
3210 Requires UBI support as well as CONFIG_LZO
3212 CONFIG_UBIFS_SILENCE_MSG
3214 Make the verbose messages from UBIFS stop printing. This leaves
3215 warnings and errors enabled.
3219 Enable building of SPL globally.
3222 LDSCRIPT for linking the SPL binary.
3224 CONFIG_SPL_MAX_FOOTPRINT
3225 Maximum size in memory allocated to the SPL, BSS included.
3226 When defined, the linker checks that the actual memory
3227 used by SPL from _start to __bss_end does not exceed it.
3228 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
3229 must not be both defined at the same time.
3232 Maximum size of the SPL image (text, data, rodata, and
3233 linker lists sections), BSS excluded.
3234 When defined, the linker checks that the actual size does
3237 CONFIG_SPL_TEXT_BASE
3238 TEXT_BASE for linking the SPL binary.
3240 CONFIG_SPL_RELOC_TEXT_BASE
3241 Address to relocate to. If unspecified, this is equal to
3242 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done).
3244 CONFIG_SPL_BSS_START_ADDR
3245 Link address for the BSS within the SPL binary.
3247 CONFIG_SPL_BSS_MAX_SIZE
3248 Maximum size in memory allocated to the SPL BSS.
3249 When defined, the linker checks that the actual memory used
3250 by SPL from __bss_start to __bss_end does not exceed it.
3251 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
3252 must not be both defined at the same time.
3255 Adress of the start of the stack SPL will use
3257 CONFIG_SPL_RELOC_STACK
3258 Adress of the start of the stack SPL will use after
3259 relocation. If unspecified, this is equal to
3262 CONFIG_SYS_SPL_MALLOC_START
3263 Starting address of the malloc pool used in SPL.
3265 CONFIG_SYS_SPL_MALLOC_SIZE
3266 The size of the malloc pool used in SPL.
3268 CONFIG_SPL_FRAMEWORK
3269 Enable the SPL framework under common/. This framework
3270 supports MMC, NAND and YMODEM loading of U-Boot and NAND
3271 NAND loading of the Linux Kernel.
3273 CONFIG_SPL_DISPLAY_PRINT
3274 For ARM, enable an optional function to print more information
3275 about the running system.
3277 CONFIG_SPL_INIT_MINIMAL
3278 Arch init code should be built for a very small image
3280 CONFIG_SPL_LIBCOMMON_SUPPORT
3281 Support for common/libcommon.o in SPL binary
3283 CONFIG_SPL_LIBDISK_SUPPORT
3284 Support for disk/libdisk.o in SPL binary
3286 CONFIG_SPL_I2C_SUPPORT
3287 Support for drivers/i2c/libi2c.o in SPL binary
3289 CONFIG_SPL_GPIO_SUPPORT
3290 Support for drivers/gpio/libgpio.o in SPL binary
3292 CONFIG_SPL_MMC_SUPPORT
3293 Support for drivers/mmc/libmmc.o in SPL binary
3295 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR,
3296 CONFIG_SYS_U_BOOT_MAX_SIZE_SECTORS,
3297 CONFIG_SYS_MMC_SD_FAT_BOOT_PARTITION
3298 Address, size and partition on the MMC to load U-Boot from
3299 when the MMC is being used in raw mode.
3301 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR
3302 Sector to load kernel uImage from when MMC is being
3303 used in raw mode (for Falcon mode)
3305 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR,
3306 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS
3307 Sector and number of sectors to load kernel argument
3308 parameters from when MMC is being used in raw mode
3311 CONFIG_SPL_FAT_SUPPORT
3312 Support for fs/fat/libfat.o in SPL binary
3314 CONFIG_SPL_FAT_LOAD_PAYLOAD_NAME
3315 Filename to read to load U-Boot when reading from FAT
3317 CONFIG_SPL_FAT_LOAD_KERNEL_NAME
3318 Filename to read to load kernel uImage when reading
3319 from FAT (for Falcon mode)
3321 CONFIG_SPL_FAT_LOAD_ARGS_NAME
3322 Filename to read to load kernel argument parameters
3323 when reading from FAT (for Falcon mode)
3325 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND
3326 Set this for NAND SPL on PPC mpc83xx targets, so that
3327 start.S waits for the rest of the SPL to load before
3328 continuing (the hardware starts execution after just
3329 loading the first page rather than the full 4K).
3331 CONFIG_SPL_NAND_BASE
3332 Include nand_base.c in the SPL. Requires
3333 CONFIG_SPL_NAND_DRIVERS.
3335 CONFIG_SPL_NAND_DRIVERS
3336 SPL uses normal NAND drivers, not minimal drivers.
3339 Include standard software ECC in the SPL
3341 CONFIG_SPL_NAND_SIMPLE
3342 Support for NAND boot using simple NAND drivers that
3343 expose the cmd_ctrl() interface.
3345 CONFIG_SPL_MPC8XXX_INIT_DDR_SUPPORT
3346 Set for the SPL on PPC mpc8xxx targets, support for
3347 drivers/ddr/fsl/libddr.o in SPL binary.
3349 CONFIG_SPL_COMMON_INIT_DDR
3350 Set for common ddr init with serial presence detect in
3353 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
3354 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
3355 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
3356 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE,
3357 CONFIG_SYS_NAND_ECCBYTES
3358 Defines the size and behavior of the NAND that SPL uses
3361 CONFIG_SPL_NAND_BOOT
3362 Add support NAND boot
3364 CONFIG_SYS_NAND_U_BOOT_OFFS
3365 Location in NAND to read U-Boot from
3367 CONFIG_SYS_NAND_U_BOOT_DST
3368 Location in memory to load U-Boot to
3370 CONFIG_SYS_NAND_U_BOOT_SIZE
3371 Size of image to load
3373 CONFIG_SYS_NAND_U_BOOT_START
3374 Entry point in loaded image to jump to
3376 CONFIG_SYS_NAND_HW_ECC_OOBFIRST
3377 Define this if you need to first read the OOB and then the
3378 data. This is used for example on davinci plattforms.
3380 CONFIG_SPL_OMAP3_ID_NAND
3381 Support for an OMAP3-specific set of functions to return the
3382 ID and MFR of the first attached NAND chip, if present.
3384 CONFIG_SPL_SERIAL_SUPPORT
3385 Support for drivers/serial/libserial.o in SPL binary
3387 CONFIG_SPL_SPI_FLASH_SUPPORT
3388 Support for drivers/mtd/spi/libspi_flash.o in SPL binary
3390 CONFIG_SPL_SPI_SUPPORT
3391 Support for drivers/spi/libspi.o in SPL binary
3393 CONFIG_SPL_RAM_DEVICE
3394 Support for running image already present in ram, in SPL binary
3396 CONFIG_SPL_LIBGENERIC_SUPPORT
3397 Support for lib/libgeneric.o in SPL binary
3399 CONFIG_SPL_ENV_SUPPORT
3400 Support for the environment operating in SPL binary
3402 CONFIG_SPL_NET_SUPPORT
3403 Support for the net/libnet.o in SPL binary.
3404 It conflicts with SPL env from storage medium specified by
3405 CONFIG_ENV_IS_xxx but CONFIG_ENV_IS_NOWHERE
3408 Image offset to which the SPL should be padded before appending
3409 the SPL payload. By default, this is defined as
3410 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
3411 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
3412 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
3415 Final target image containing SPL and payload. Some SPLs
3416 use an arch-specific makefile fragment instead, for
3417 example if more than one image needs to be produced.
3419 CONFIG_FIT_SPL_PRINT
3420 Printing information about a FIT image adds quite a bit of
3421 code to SPL. So this is normally disabled in SPL. Use this
3422 option to re-enable it. This will affect the output of the
3423 bootm command when booting a FIT image.
3427 Enable building of TPL globally.
3430 Image offset to which the TPL should be padded before appending
3431 the TPL payload. By default, this is defined as
3432 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
3433 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
3434 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
3439 [so far only for SMDK2400 boards]
3441 - Modem support enable:
3442 CONFIG_MODEM_SUPPORT
3444 - RTS/CTS Flow control enable:
3447 - Modem debug support:
3448 CONFIG_MODEM_SUPPORT_DEBUG
3450 Enables debugging stuff (char screen[1024], dbg())
3451 for modem support. Useful only with BDI2000.
3453 - Interrupt support (PPC):
3455 There are common interrupt_init() and timer_interrupt()
3456 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
3457 for CPU specific initialization. interrupt_init_cpu()
3458 should set decrementer_count to appropriate value. If
3459 CPU resets decrementer automatically after interrupt
3460 (ppc4xx) it should set decrementer_count to zero.
3461 timer_interrupt() calls timer_interrupt_cpu() for CPU
3462 specific handling. If board has watchdog / status_led
3463 / other_activity_monitor it works automatically from
3464 general timer_interrupt().
3468 In the target system modem support is enabled when a
3469 specific key (key combination) is pressed during
3470 power-on. Otherwise U-Boot will boot normally
3471 (autoboot). The key_pressed() function is called from
3472 board_init(). Currently key_pressed() is a dummy
3473 function, returning 1 and thus enabling modem
3476 If there are no modem init strings in the
3477 environment, U-Boot proceed to autoboot; the
3478 previous output (banner, info printfs) will be
3481 See also: doc/README.Modem
3483 Board initialization settings:
3484 ------------------------------
3486 During Initialization u-boot calls a number of board specific functions
3487 to allow the preparation of board specific prerequisites, e.g. pin setup
3488 before drivers are initialized. To enable these callbacks the
3489 following configuration macros have to be defined. Currently this is
3490 architecture specific, so please check arch/your_architecture/lib/board.c
3491 typically in board_init_f() and board_init_r().
3493 - CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
3494 - CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
3495 - CONFIG_BOARD_LATE_INIT: Call board_late_init()
3496 - CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init()
3498 Configuration Settings:
3499 -----------------------
3501 - CONFIG_SYS_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit.
3502 Optionally it can be defined to support 64-bit memory commands.
3504 - CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
3505 undefine this when you're short of memory.
3507 - CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
3508 width of the commands listed in the 'help' command output.
3510 - CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
3511 prompt for user input.
3513 - CONFIG_SYS_CBSIZE: Buffer size for input from the Console
3515 - CONFIG_SYS_PBSIZE: Buffer size for Console output
3517 - CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
3519 - CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
3520 the application (usually a Linux kernel) when it is
3523 - CONFIG_SYS_BAUDRATE_TABLE:
3524 List of legal baudrate settings for this board.
3526 - CONFIG_SYS_CONSOLE_INFO_QUIET
3527 Suppress display of console information at boot.
3529 - CONFIG_SYS_CONSOLE_IS_IN_ENV
3530 If the board specific function
3531 extern int overwrite_console (void);
3532 returns 1, the stdin, stderr and stdout are switched to the
3533 serial port, else the settings in the environment are used.
3535 - CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE
3536 Enable the call to overwrite_console().
3538 - CONFIG_SYS_CONSOLE_ENV_OVERWRITE
3539 Enable overwrite of previous console environment settings.
3541 - CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
3542 Begin and End addresses of the area used by the
3545 - CONFIG_SYS_ALT_MEMTEST:
3546 Enable an alternate, more extensive memory test.
3548 - CONFIG_SYS_MEMTEST_SCRATCH:
3549 Scratch address used by the alternate memory test
3550 You only need to set this if address zero isn't writeable
3552 - CONFIG_SYS_MEM_TOP_HIDE (PPC only):
3553 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
3554 this specified memory area will get subtracted from the top
3555 (end) of RAM and won't get "touched" at all by U-Boot. By
3556 fixing up gd->ram_size the Linux kernel should gets passed
3557 the now "corrected" memory size and won't touch it either.
3558 This should work for arch/ppc and arch/powerpc. Only Linux
3559 board ports in arch/powerpc with bootwrapper support that
3560 recalculate the memory size from the SDRAM controller setup
3561 will have to get fixed in Linux additionally.
3563 This option can be used as a workaround for the 440EPx/GRx
3564 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
3567 WARNING: Please make sure that this value is a multiple of
3568 the Linux page size (normally 4k). If this is not the case,
3569 then the end address of the Linux memory will be located at a
3570 non page size aligned address and this could cause major
3573 - CONFIG_SYS_LOADS_BAUD_CHANGE:
3574 Enable temporary baudrate change while serial download
3576 - CONFIG_SYS_SDRAM_BASE:
3577 Physical start address of SDRAM. _Must_ be 0 here.
3579 - CONFIG_SYS_MBIO_BASE:
3580 Physical start address of Motherboard I/O (if using a
3583 - CONFIG_SYS_FLASH_BASE:
3584 Physical start address of Flash memory.
3586 - CONFIG_SYS_MONITOR_BASE:
3587 Physical start address of boot monitor code (set by
3588 make config files to be same as the text base address
3589 (CONFIG_SYS_TEXT_BASE) used when linking) - same as
3590 CONFIG_SYS_FLASH_BASE when booting from flash.
3592 - CONFIG_SYS_MONITOR_LEN:
3593 Size of memory reserved for monitor code, used to
3594 determine _at_compile_time_ (!) if the environment is
3595 embedded within the U-Boot image, or in a separate
3598 - CONFIG_SYS_MALLOC_LEN:
3599 Size of DRAM reserved for malloc() use.
3601 - CONFIG_SYS_BOOTM_LEN:
3602 Normally compressed uImages are limited to an
3603 uncompressed size of 8 MBytes. If this is not enough,
3604 you can define CONFIG_SYS_BOOTM_LEN in your board config file
3605 to adjust this setting to your needs.
3607 - CONFIG_SYS_BOOTMAPSZ:
3608 Maximum size of memory mapped by the startup code of
3609 the Linux kernel; all data that must be processed by
3610 the Linux kernel (bd_info, boot arguments, FDT blob if
3611 used) must be put below this limit, unless "bootm_low"
3612 environment variable is defined and non-zero. In such case
3613 all data for the Linux kernel must be between "bootm_low"
3614 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
3615 variable "bootm_mapsize" will override the value of
3616 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
3617 then the value in "bootm_size" will be used instead.
3619 - CONFIG_SYS_BOOT_RAMDISK_HIGH:
3620 Enable initrd_high functionality. If defined then the
3621 initrd_high feature is enabled and the bootm ramdisk subcommand
3624 - CONFIG_SYS_BOOT_GET_CMDLINE:
3625 Enables allocating and saving kernel cmdline in space between
3626 "bootm_low" and "bootm_low" + BOOTMAPSZ.
3628 - CONFIG_SYS_BOOT_GET_KBD:
3629 Enables allocating and saving a kernel copy of the bd_info in
3630 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
3632 - CONFIG_SYS_MAX_FLASH_BANKS:
3633 Max number of Flash memory banks
3635 - CONFIG_SYS_MAX_FLASH_SECT:
3636 Max number of sectors on a Flash chip
3638 - CONFIG_SYS_FLASH_ERASE_TOUT:
3639 Timeout for Flash erase operations (in ms)
3641 - CONFIG_SYS_FLASH_WRITE_TOUT:
3642 Timeout for Flash write operations (in ms)
3644 - CONFIG_SYS_FLASH_LOCK_TOUT
3645 Timeout for Flash set sector lock bit operation (in ms)
3647 - CONFIG_SYS_FLASH_UNLOCK_TOUT
3648 Timeout for Flash clear lock bits operation (in ms)
3650 - CONFIG_SYS_FLASH_PROTECTION
3651 If defined, hardware flash sectors protection is used
3652 instead of U-Boot software protection.
3654 - CONFIG_SYS_DIRECT_FLASH_TFTP:
3656 Enable TFTP transfers directly to flash memory;
3657 without this option such a download has to be
3658 performed in two steps: (1) download to RAM, and (2)
3659 copy from RAM to flash.
3661 The two-step approach is usually more reliable, since
3662 you can check if the download worked before you erase
3663 the flash, but in some situations (when system RAM is
3664 too limited to allow for a temporary copy of the
3665 downloaded image) this option may be very useful.
3667 - CONFIG_SYS_FLASH_CFI:
3668 Define if the flash driver uses extra elements in the
3669 common flash structure for storing flash geometry.
3671 - CONFIG_FLASH_CFI_DRIVER
3672 This option also enables the building of the cfi_flash driver
3673 in the drivers directory
3675 - CONFIG_FLASH_CFI_MTD
3676 This option enables the building of the cfi_mtd driver
3677 in the drivers directory. The driver exports CFI flash
3680 - CONFIG_SYS_FLASH_USE_BUFFER_WRITE
3681 Use buffered writes to flash.
3683 - CONFIG_FLASH_SPANSION_S29WS_N
3684 s29ws-n MirrorBit flash has non-standard addresses for buffered
3687 - CONFIG_SYS_FLASH_QUIET_TEST
3688 If this option is defined, the common CFI flash doesn't
3689 print it's warning upon not recognized FLASH banks. This
3690 is useful, if some of the configured banks are only
3691 optionally available.
3693 - CONFIG_FLASH_SHOW_PROGRESS
3694 If defined (must be an integer), print out countdown
3695 digits and dots. Recommended value: 45 (9..1) for 80
3696 column displays, 15 (3..1) for 40 column displays.
3698 - CONFIG_FLASH_VERIFY
3699 If defined, the content of the flash (destination) is compared
3700 against the source after the write operation. An error message
3701 will be printed when the contents are not identical.
3702 Please note that this option is useless in nearly all cases,
3703 since such flash programming errors usually are detected earlier
3704 while unprotecting/erasing/programming. Please only enable
3705 this option if you really know what you are doing.
3707 - CONFIG_SYS_RX_ETH_BUFFER:
3708 Defines the number of Ethernet receive buffers. On some
3709 Ethernet controllers it is recommended to set this value
3710 to 8 or even higher (EEPRO100 or 405 EMAC), since all
3711 buffers can be full shortly after enabling the interface
3712 on high Ethernet traffic.
3713 Defaults to 4 if not defined.
3715 - CONFIG_ENV_MAX_ENTRIES
3717 Maximum number of entries in the hash table that is used
3718 internally to store the environment settings. The default
3719 setting is supposed to be generous and should work in most
3720 cases. This setting can be used to tune behaviour; see
3721 lib/hashtable.c for details.
3723 - CONFIG_ENV_FLAGS_LIST_DEFAULT
3724 - CONFIG_ENV_FLAGS_LIST_STATIC
3725 Enable validation of the values given to environment variables when
3726 calling env set. Variables can be restricted to only decimal,
3727 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined,
3728 the variables can also be restricted to IP address or MAC address.
3730 The format of the list is:
3731 type_attribute = [s|d|x|b|i|m]
3732 access_atribute = [a|r|o|c]
3733 attributes = type_attribute[access_atribute]
3734 entry = variable_name[:attributes]
3737 The type attributes are:
3738 s - String (default)
3741 b - Boolean ([1yYtT|0nNfF])
3745 The access attributes are:
3751 - CONFIG_ENV_FLAGS_LIST_DEFAULT
3752 Define this to a list (string) to define the ".flags"
3753 envirnoment variable in the default or embedded environment.
3755 - CONFIG_ENV_FLAGS_LIST_STATIC
3756 Define this to a list (string) to define validation that
3757 should be done if an entry is not found in the ".flags"
3758 environment variable. To override a setting in the static
3759 list, simply add an entry for the same variable name to the
3762 - CONFIG_ENV_ACCESS_IGNORE_FORCE
3763 If defined, don't allow the -f switch to env set override variable
3766 - CONFIG_SYS_GENERIC_BOARD
3767 This selects the architecture-generic board system instead of the
3768 architecture-specific board files. It is intended to move boards
3769 to this new framework over time. Defining this will disable the
3770 arch/foo/lib/board.c file and use common/board_f.c and
3771 common/board_r.c instead. To use this option your architecture
3772 must support it (i.e. must define __HAVE_ARCH_GENERIC_BOARD in
3773 its config.mk file). If you find problems enabling this option on
3774 your board please report the problem and send patches!
3776 - CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC (OMAP only)
3777 This is set by OMAP boards for the max time that reset should
3778 be asserted. See doc/README.omap-reset-time for details on how
3779 the value can be calulated on a given board.
3781 The following definitions that deal with the placement and management
3782 of environment data (variable area); in general, we support the
3783 following configurations:
3785 - CONFIG_BUILD_ENVCRC:
3787 Builds up envcrc with the target environment so that external utils
3788 may easily extract it and embed it in final U-Boot images.
3790 - CONFIG_ENV_IS_IN_FLASH:
3792 Define this if the environment is in flash memory.
3794 a) The environment occupies one whole flash sector, which is
3795 "embedded" in the text segment with the U-Boot code. This
3796 happens usually with "bottom boot sector" or "top boot
3797 sector" type flash chips, which have several smaller
3798 sectors at the start or the end. For instance, such a
3799 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
3800 such a case you would place the environment in one of the
3801 4 kB sectors - with U-Boot code before and after it. With
3802 "top boot sector" type flash chips, you would put the
3803 environment in one of the last sectors, leaving a gap
3804 between U-Boot and the environment.
3806 - CONFIG_ENV_OFFSET:
3808 Offset of environment data (variable area) to the
3809 beginning of flash memory; for instance, with bottom boot
3810 type flash chips the second sector can be used: the offset
3811 for this sector is given here.
3813 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE.
3817 This is just another way to specify the start address of
3818 the flash sector containing the environment (instead of
3821 - CONFIG_ENV_SECT_SIZE:
3823 Size of the sector containing the environment.
3826 b) Sometimes flash chips have few, equal sized, BIG sectors.
3827 In such a case you don't want to spend a whole sector for
3832 If you use this in combination with CONFIG_ENV_IS_IN_FLASH
3833 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part
3834 of this flash sector for the environment. This saves
3835 memory for the RAM copy of the environment.
3837 It may also save flash memory if you decide to use this
3838 when your environment is "embedded" within U-Boot code,
3839 since then the remainder of the flash sector could be used
3840 for U-Boot code. It should be pointed out that this is
3841 STRONGLY DISCOURAGED from a robustness point of view:
3842 updating the environment in flash makes it always
3843 necessary to erase the WHOLE sector. If something goes
3844 wrong before the contents has been restored from a copy in
3845 RAM, your target system will be dead.
3847 - CONFIG_ENV_ADDR_REDUND
3848 CONFIG_ENV_SIZE_REDUND
3850 These settings describe a second storage area used to hold
3851 a redundant copy of the environment data, so that there is
3852 a valid backup copy in case there is a power failure during
3853 a "saveenv" operation.
3855 BE CAREFUL! Any changes to the flash layout, and some changes to the
3856 source code will make it necessary to adapt <board>/u-boot.lds*
3860 - CONFIG_ENV_IS_IN_NVRAM:
3862 Define this if you have some non-volatile memory device
3863 (NVRAM, battery buffered SRAM) which you want to use for the
3869 These two #defines are used to determine the memory area you
3870 want to use for environment. It is assumed that this memory
3871 can just be read and written to, without any special
3874 BE CAREFUL! The first access to the environment happens quite early
3875 in U-Boot initalization (when we try to get the setting of for the
3876 console baudrate). You *MUST* have mapped your NVRAM area then, or
3879 Please note that even with NVRAM we still use a copy of the
3880 environment in RAM: we could work on NVRAM directly, but we want to
3881 keep settings there always unmodified except somebody uses "saveenv"
3882 to save the current settings.
3885 - CONFIG_ENV_IS_IN_EEPROM:
3887 Use this if you have an EEPROM or similar serial access
3888 device and a driver for it.
3890 - CONFIG_ENV_OFFSET:
3893 These two #defines specify the offset and size of the
3894 environment area within the total memory of your EEPROM.
3896 - CONFIG_SYS_I2C_EEPROM_ADDR:
3897 If defined, specified the chip address of the EEPROM device.
3898 The default address is zero.
3900 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS:
3901 If defined, the number of bits used to address bytes in a
3902 single page in the EEPROM device. A 64 byte page, for example
3903 would require six bits.
3905 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS:
3906 If defined, the number of milliseconds to delay between
3907 page writes. The default is zero milliseconds.
3909 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN:
3910 The length in bytes of the EEPROM memory array address. Note
3911 that this is NOT the chip address length!
3913 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW:
3914 EEPROM chips that implement "address overflow" are ones
3915 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
3916 address and the extra bits end up in the "chip address" bit
3917 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
3920 Note that we consider the length of the address field to
3921 still be one byte because the extra address bits are hidden
3922 in the chip address.
3924 - CONFIG_SYS_EEPROM_SIZE:
3925 The size in bytes of the EEPROM device.
3927 - CONFIG_ENV_EEPROM_IS_ON_I2C
3928 define this, if you have I2C and SPI activated, and your
3929 EEPROM, which holds the environment, is on the I2C bus.
3931 - CONFIG_I2C_ENV_EEPROM_BUS
3932 if you have an Environment on an EEPROM reached over
3933 I2C muxes, you can define here, how to reach this
3934 EEPROM. For example:
3936 #define CONFIG_I2C_ENV_EEPROM_BUS 1
3938 EEPROM which holds the environment, is reached over
3939 a pca9547 i2c mux with address 0x70, channel 3.
3941 - CONFIG_ENV_IS_IN_DATAFLASH:
3943 Define this if you have a DataFlash memory device which you
3944 want to use for the environment.
3946 - CONFIG_ENV_OFFSET:
3950 These three #defines specify the offset and size of the
3951 environment area within the total memory of your DataFlash placed
3952 at the specified address.
3954 - CONFIG_ENV_IS_IN_REMOTE:
3956 Define this if you have a remote memory space which you
3957 want to use for the local device's environment.
3962 These two #defines specify the address and size of the
3963 environment area within the remote memory space. The
3964 local device can get the environment from remote memory
3965 space by SRIO or PCIE links.
3967 BE CAREFUL! For some special cases, the local device can not use
3968 "saveenv" command. For example, the local device will get the
3969 environment stored in a remote NOR flash by SRIO or PCIE link,
3970 but it can not erase, write this NOR flash by SRIO or PCIE interface.
3972 - CONFIG_ENV_IS_IN_NAND:
3974 Define this if you have a NAND device which you want to use
3975 for the environment.
3977 - CONFIG_ENV_OFFSET:
3980 These two #defines specify the offset and size of the environment
3981 area within the first NAND device. CONFIG_ENV_OFFSET must be
3982 aligned to an erase block boundary.
3984 - CONFIG_ENV_OFFSET_REDUND (optional):
3986 This setting describes a second storage area of CONFIG_ENV_SIZE
3987 size used to hold a redundant copy of the environment data, so
3988 that there is a valid backup copy in case there is a power failure
3989 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be
3990 aligned to an erase block boundary.
3992 - CONFIG_ENV_RANGE (optional):
3994 Specifies the length of the region in which the environment
3995 can be written. This should be a multiple of the NAND device's
3996 block size. Specifying a range with more erase blocks than
3997 are needed to hold CONFIG_ENV_SIZE allows bad blocks within
3998 the range to be avoided.
4000 - CONFIG_ENV_OFFSET_OOB (optional):
4002 Enables support for dynamically retrieving the offset of the
4003 environment from block zero's out-of-band data. The
4004 "nand env.oob" command can be used to record this offset.
4005 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when
4006 using CONFIG_ENV_OFFSET_OOB.
4008 - CONFIG_NAND_ENV_DST
4010 Defines address in RAM to which the nand_spl code should copy the
4011 environment. If redundant environment is used, it will be copied to
4012 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
4014 - CONFIG_ENV_IS_IN_UBI:
4016 Define this if you have an UBI volume that you want to use for the
4017 environment. This has the benefit of wear-leveling the environment
4018 accesses, which is important on NAND.
4020 - CONFIG_ENV_UBI_PART:
4022 Define this to a string that is the mtd partition containing the UBI.
4024 - CONFIG_ENV_UBI_VOLUME:
4026 Define this to the name of the volume that you want to store the
4029 - CONFIG_ENV_UBI_VOLUME_REDUND:
4031 Define this to the name of another volume to store a second copy of
4032 the environment in. This will enable redundant environments in UBI.
4033 It is assumed that both volumes are in the same MTD partition.
4035 - CONFIG_UBI_SILENCE_MSG
4036 - CONFIG_UBIFS_SILENCE_MSG
4038 You will probably want to define these to avoid a really noisy system
4039 when storing the env in UBI.
4041 - CONFIG_ENV_IS_IN_MMC:
4043 Define this if you have an MMC device which you want to use for the
4046 - CONFIG_SYS_MMC_ENV_DEV:
4048 Specifies which MMC device the environment is stored in.
4050 - CONFIG_SYS_MMC_ENV_PART (optional):
4052 Specifies which MMC partition the environment is stored in. If not
4053 set, defaults to partition 0, the user area. Common values might be
4054 1 (first MMC boot partition), 2 (second MMC boot partition).
4056 - CONFIG_ENV_OFFSET:
4059 These two #defines specify the offset and size of the environment
4060 area within the specified MMC device.
4062 If offset is positive (the usual case), it is treated as relative to
4063 the start of the MMC partition. If offset is negative, it is treated
4064 as relative to the end of the MMC partition. This can be useful if
4065 your board may be fitted with different MMC devices, which have
4066 different sizes for the MMC partitions, and you always want the
4067 environment placed at the very end of the partition, to leave the
4068 maximum possible space before it, to store other data.
4070 These two values are in units of bytes, but must be aligned to an
4071 MMC sector boundary.
4073 - CONFIG_ENV_OFFSET_REDUND (optional):
4075 Specifies a second storage area, of CONFIG_ENV_SIZE size, used to
4076 hold a redundant copy of the environment data. This provides a
4077 valid backup copy in case the other copy is corrupted, e.g. due
4078 to a power failure during a "saveenv" operation.
4080 This value may also be positive or negative; this is handled in the
4081 same way as CONFIG_ENV_OFFSET.
4083 This value is also in units of bytes, but must also be aligned to
4084 an MMC sector boundary.
4086 - CONFIG_ENV_SIZE_REDUND (optional):
4088 This value need not be set, even when CONFIG_ENV_OFFSET_REDUND is
4089 set. If this value is set, it must be set to the same value as
4092 - CONFIG_SYS_SPI_INIT_OFFSET
4094 Defines offset to the initial SPI buffer area in DPRAM. The
4095 area is used at an early stage (ROM part) if the environment
4096 is configured to reside in the SPI EEPROM: We need a 520 byte
4097 scratch DPRAM area. It is used between the two initialization
4098 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
4099 to be a good choice since it makes it far enough from the
4100 start of the data area as well as from the stack pointer.
4102 Please note that the environment is read-only until the monitor
4103 has been relocated to RAM and a RAM copy of the environment has been
4104 created; also, when using EEPROM you will have to use getenv_f()
4105 until then to read environment variables.
4107 The environment is protected by a CRC32 checksum. Before the monitor
4108 is relocated into RAM, as a result of a bad CRC you will be working
4109 with the compiled-in default environment - *silently*!!! [This is
4110 necessary, because the first environment variable we need is the
4111 "baudrate" setting for the console - if we have a bad CRC, we don't
4112 have any device yet where we could complain.]
4114 Note: once the monitor has been relocated, then it will complain if
4115 the default environment is used; a new CRC is computed as soon as you
4116 use the "saveenv" command to store a valid environment.
4118 - CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
4119 Echo the inverted Ethernet link state to the fault LED.
4121 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
4122 also needs to be defined.
4124 - CONFIG_SYS_FAULT_MII_ADDR:
4125 MII address of the PHY to check for the Ethernet link state.
4127 - CONFIG_NS16550_MIN_FUNCTIONS:
4128 Define this if you desire to only have use of the NS16550_init
4129 and NS16550_putc functions for the serial driver located at
4130 drivers/serial/ns16550.c. This option is useful for saving
4131 space for already greatly restricted images, including but not
4132 limited to NAND_SPL configurations.
4134 - CONFIG_DISPLAY_BOARDINFO
4135 Display information about the board that U-Boot is running on
4136 when U-Boot starts up. The board function checkboard() is called
4139 - CONFIG_DISPLAY_BOARDINFO_LATE
4140 Similar to the previous option, but display this information
4141 later, once stdio is running and output goes to the LCD, if
4144 Low Level (hardware related) configuration options:
4145 ---------------------------------------------------
4147 - CONFIG_SYS_CACHELINE_SIZE:
4148 Cache Line Size of the CPU.
4150 - CONFIG_SYS_DEFAULT_IMMR:
4151 Default address of the IMMR after system reset.
4153 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
4154 and RPXsuper) to be able to adjust the position of
4155 the IMMR register after a reset.
4157 - CONFIG_SYS_CCSRBAR_DEFAULT:
4158 Default (power-on reset) physical address of CCSR on Freescale
4161 - CONFIG_SYS_CCSRBAR:
4162 Virtual address of CCSR. On a 32-bit build, this is typically
4163 the same value as CONFIG_SYS_CCSRBAR_DEFAULT.
4165 CONFIG_SYS_DEFAULT_IMMR must also be set to this value,
4166 for cross-platform code that uses that macro instead.
4168 - CONFIG_SYS_CCSRBAR_PHYS:
4169 Physical address of CCSR. CCSR can be relocated to a new
4170 physical address, if desired. In this case, this macro should
4171 be set to that address. Otherwise, it should be set to the
4172 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR
4173 is typically relocated on 36-bit builds. It is recommended
4174 that this macro be defined via the _HIGH and _LOW macros:
4176 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH
4177 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW)
4179 - CONFIG_SYS_CCSRBAR_PHYS_HIGH:
4180 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically
4181 either 0 (32-bit build) or 0xF (36-bit build). This macro is
4182 used in assembly code, so it must not contain typecasts or
4183 integer size suffixes (e.g. "ULL").
4185 - CONFIG_SYS_CCSRBAR_PHYS_LOW:
4186 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is
4187 used in assembly code, so it must not contain typecasts or
4188 integer size suffixes (e.g. "ULL").
4190 - CONFIG_SYS_CCSR_DO_NOT_RELOCATE:
4191 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be
4192 forced to a value that ensures that CCSR is not relocated.
4194 - Floppy Disk Support:
4195 CONFIG_SYS_FDC_DRIVE_NUMBER
4197 the default drive number (default value 0)
4199 CONFIG_SYS_ISA_IO_STRIDE
4201 defines the spacing between FDC chipset registers
4204 CONFIG_SYS_ISA_IO_OFFSET
4206 defines the offset of register from address. It
4207 depends on which part of the data bus is connected to
4208 the FDC chipset. (default value 0)
4210 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
4211 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
4214 if CONFIG_SYS_FDC_HW_INIT is defined, then the function
4215 fdc_hw_init() is called at the beginning of the FDC
4216 setup. fdc_hw_init() must be provided by the board
4217 source code. It is used to make hardware dependant
4221 Most IDE controllers were designed to be connected with PCI
4222 interface. Only few of them were designed for AHB interface.
4223 When software is doing ATA command and data transfer to
4224 IDE devices through IDE-AHB controller, some additional
4225 registers accessing to these kind of IDE-AHB controller
4228 - CONFIG_SYS_IMMR: Physical address of the Internal Memory.
4229 DO NOT CHANGE unless you know exactly what you're
4230 doing! (11-4) [MPC8xx/82xx systems only]
4232 - CONFIG_SYS_INIT_RAM_ADDR:
4234 Start address of memory area that can be used for
4235 initial data and stack; please note that this must be
4236 writable memory that is working WITHOUT special
4237 initialization, i. e. you CANNOT use normal RAM which
4238 will become available only after programming the
4239 memory controller and running certain initialization
4242 U-Boot uses the following memory types:
4243 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
4244 - MPC824X: data cache
4245 - PPC4xx: data cache
4247 - CONFIG_SYS_GBL_DATA_OFFSET:
4249 Offset of the initial data structure in the memory
4250 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
4251 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
4252 data is located at the end of the available space
4253 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
4254 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just
4255 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
4256 CONFIG_SYS_GBL_DATA_OFFSET) downward.
4259 On the MPC824X (or other systems that use the data
4260 cache for initial memory) the address chosen for
4261 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
4262 point to an otherwise UNUSED address space between
4263 the top of RAM and the start of the PCI space.
4265 - CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6)
4267 - CONFIG_SYS_SYPCR: System Protection Control (11-9)
4269 - CONFIG_SYS_TBSCR: Time Base Status and Control (11-26)
4271 - CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31)
4273 - CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
4275 - CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
4277 - CONFIG_SYS_OR_TIMING_SDRAM:
4280 - CONFIG_SYS_MAMR_PTA:
4281 periodic timer for refresh
4283 - CONFIG_SYS_DER: Debug Event Register (37-47)
4285 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
4286 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
4287 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
4288 CONFIG_SYS_BR1_PRELIM:
4289 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
4291 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
4292 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
4293 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
4294 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
4296 - CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K,
4297 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL:
4298 Machine Mode Register and Memory Periodic Timer
4299 Prescaler definitions (SDRAM timing)
4301 - CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]:
4302 enable I2C microcode relocation patch (MPC8xx);
4303 define relocation offset in DPRAM [DSP2]
4305 - CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]:
4306 enable SMC microcode relocation patch (MPC8xx);
4307 define relocation offset in DPRAM [SMC1]
4309 - CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]:
4310 enable SPI microcode relocation patch (MPC8xx);
4311 define relocation offset in DPRAM [SCC4]
4313 - CONFIG_SYS_USE_OSCCLK:
4314 Use OSCM clock mode on MBX8xx board. Be careful,
4315 wrong setting might damage your board. Read
4316 doc/README.MBX before setting this variable!
4318 - CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
4319 Offset of the bootmode word in DPRAM used by post
4320 (Power On Self Tests). This definition overrides
4321 #define'd default value in commproc.h resp.
4324 - CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB,
4325 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL,
4326 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS,
4327 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB,
4328 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
4329 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL,
4330 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE,
4331 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only)
4332 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set.
4334 - CONFIG_PCI_DISABLE_PCIE:
4335 Disable PCI-Express on systems where it is supported but not
4338 - CONFIG_PCI_ENUM_ONLY
4339 Only scan through and get the devices on the busses.
4340 Don't do any setup work, presumably because someone or
4341 something has already done it, and we don't need to do it
4342 a second time. Useful for platforms that are pre-booted
4343 by coreboot or similar.
4345 - CONFIG_PCI_INDIRECT_BRIDGE:
4346 Enable support for indirect PCI bridges.
4349 Chip has SRIO or not
4352 Board has SRIO 1 port available
4355 Board has SRIO 2 port available
4357 - CONFIG_SRIO_PCIE_BOOT_MASTER
4358 Board can support master function for Boot from SRIO and PCIE
4360 - CONFIG_SYS_SRIOn_MEM_VIRT:
4361 Virtual Address of SRIO port 'n' memory region
4363 - CONFIG_SYS_SRIOn_MEM_PHYS:
4364 Physical Address of SRIO port 'n' memory region
4366 - CONFIG_SYS_SRIOn_MEM_SIZE:
4367 Size of SRIO port 'n' memory region
4369 - CONFIG_SYS_NAND_BUSWIDTH_16BIT
4370 Defined to tell the NAND controller that the NAND chip is using
4372 Not all NAND drivers use this symbol.
4373 Example of drivers that use it:
4374 - drivers/mtd/nand/ndfc.c
4375 - drivers/mtd/nand/mxc_nand.c
4377 - CONFIG_SYS_NDFC_EBC0_CFG
4378 Sets the EBC0_CFG register for the NDFC. If not defined
4379 a default value will be used.
4382 Get DDR timing information from an I2C EEPROM. Common
4383 with pluggable memory modules such as SODIMMs
4386 I2C address of the SPD EEPROM
4388 - CONFIG_SYS_SPD_BUS_NUM
4389 If SPD EEPROM is on an I2C bus other than the first
4390 one, specify here. Note that the value must resolve
4391 to something your driver can deal with.
4393 - CONFIG_SYS_DDR_RAW_TIMING
4394 Get DDR timing information from other than SPD. Common with
4395 soldered DDR chips onboard without SPD. DDR raw timing
4396 parameters are extracted from datasheet and hard-coded into
4397 header files or board specific files.
4399 - CONFIG_FSL_DDR_INTERACTIVE
4400 Enable interactive DDR debugging. See doc/README.fsl-ddr.
4402 - CONFIG_SYS_83XX_DDR_USES_CS0
4403 Only for 83xx systems. If specified, then DDR should
4404 be configured using CS0 and CS1 instead of CS2 and CS3.
4406 - CONFIG_ETHER_ON_FEC[12]
4407 Define to enable FEC[12] on a 8xx series processor.
4409 - CONFIG_FEC[12]_PHY
4410 Define to the hardcoded PHY address which corresponds
4411 to the given FEC; i. e.
4412 #define CONFIG_FEC1_PHY 4
4413 means that the PHY with address 4 is connected to FEC1
4415 When set to -1, means to probe for first available.
4417 - CONFIG_FEC[12]_PHY_NORXERR
4418 The PHY does not have a RXERR line (RMII only).
4419 (so program the FEC to ignore it).
4422 Enable RMII mode for all FECs.
4423 Note that this is a global option, we can't
4424 have one FEC in standard MII mode and another in RMII mode.
4426 - CONFIG_CRC32_VERIFY
4427 Add a verify option to the crc32 command.
4430 => crc32 -v <address> <count> <crc32>
4432 Where address/count indicate a memory area
4433 and crc32 is the correct crc32 which the
4437 Add the "loopw" memory command. This only takes effect if
4438 the memory commands are activated globally (CONFIG_CMD_MEM).
4441 Add the "mdc" and "mwc" memory commands. These are cyclic
4446 This command will print 4 bytes (10,11,12,13) each 500 ms.
4448 => mwc.l 100 12345678 10
4449 This command will write 12345678 to address 100 all 10 ms.
4451 This only takes effect if the memory commands are activated
4452 globally (CONFIG_CMD_MEM).
4454 - CONFIG_SKIP_LOWLEVEL_INIT
4455 [ARM, NDS32, MIPS only] If this variable is defined, then certain
4456 low level initializations (like setting up the memory
4457 controller) are omitted and/or U-Boot does not
4458 relocate itself into RAM.
4460 Normally this variable MUST NOT be defined. The only
4461 exception is when U-Boot is loaded (to RAM) by some
4462 other boot loader or by a debugger which performs
4463 these initializations itself.
4466 Modifies the behaviour of start.S when compiling a loader
4467 that is executed before the actual U-Boot. E.g. when
4468 compiling a NAND SPL.
4471 Modifies the behaviour of start.S when compiling a loader
4472 that is executed after the SPL and before the actual U-Boot.
4473 It is loaded by the SPL.
4475 - CONFIG_SYS_MPC85XX_NO_RESETVEC
4476 Only for 85xx systems. If this variable is specified, the section
4477 .resetvec is not kept and the section .bootpg is placed in the
4478 previous 4k of the .text section.
4480 - CONFIG_ARCH_MAP_SYSMEM
4481 Generally U-Boot (and in particular the md command) uses
4482 effective address. It is therefore not necessary to regard
4483 U-Boot address as virtual addresses that need to be translated
4484 to physical addresses. However, sandbox requires this, since
4485 it maintains its own little RAM buffer which contains all
4486 addressable memory. This option causes some memory accesses
4487 to be mapped through map_sysmem() / unmap_sysmem().
4489 - CONFIG_USE_ARCH_MEMCPY
4490 CONFIG_USE_ARCH_MEMSET
4491 If these options are used a optimized version of memcpy/memset will
4492 be used if available. These functions may be faster under some
4493 conditions but may increase the binary size.
4495 - CONFIG_X86_RESET_VECTOR
4496 If defined, the x86 reset vector code is included. This is not
4497 needed when U-Boot is running from Coreboot.
4500 Defines the MPU clock speed (in MHz).
4502 NOTE : currently only supported on AM335x platforms.
4504 - CONFIG_SPL_AM33XX_ENABLE_RTC32K_OSC:
4505 Enables the RTC32K OSC on AM33xx based plattforms
4507 Freescale QE/FMAN Firmware Support:
4508 -----------------------------------
4510 The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
4511 loading of "firmware", which is encoded in the QE firmware binary format.
4512 This firmware often needs to be loaded during U-Boot booting, so macros
4513 are used to identify the storage device (NOR flash, SPI, etc) and the address
4516 - CONFIG_SYS_FMAN_FW_ADDR
4517 The address in the storage device where the FMAN microcode is located. The
4518 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
4521 - CONFIG_SYS_QE_FW_ADDR
4522 The address in the storage device where the QE microcode is located. The
4523 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
4526 - CONFIG_SYS_QE_FMAN_FW_LENGTH
4527 The maximum possible size of the firmware. The firmware binary format
4528 has a field that specifies the actual size of the firmware, but it
4529 might not be possible to read any part of the firmware unless some
4530 local storage is allocated to hold the entire firmware first.
4532 - CONFIG_SYS_QE_FMAN_FW_IN_NOR
4533 Specifies that QE/FMAN firmware is located in NOR flash, mapped as
4534 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the
4535 virtual address in NOR flash.
4537 - CONFIG_SYS_QE_FMAN_FW_IN_NAND
4538 Specifies that QE/FMAN firmware is located in NAND flash.
4539 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.
4541 - CONFIG_SYS_QE_FMAN_FW_IN_MMC
4542 Specifies that QE/FMAN firmware is located on the primary SD/MMC
4543 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
4545 - CONFIG_SYS_QE_FMAN_FW_IN_SPIFLASH
4546 Specifies that QE/FMAN firmware is located on the primary SPI
4547 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
4549 - CONFIG_SYS_QE_FMAN_FW_IN_REMOTE
4550 Specifies that QE/FMAN firmware is located in the remote (master)
4551 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which
4552 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound
4553 window->master inbound window->master LAW->the ucode address in
4554 master's memory space.
4556 Building the Software:
4557 ======================
4559 Building U-Boot has been tested in several native build environments
4560 and in many different cross environments. Of course we cannot support
4561 all possibly existing versions of cross development tools in all
4562 (potentially obsolete) versions. In case of tool chain problems we
4563 recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
4564 which is extensively used to build and test U-Boot.
4566 If you are not using a native environment, it is assumed that you
4567 have GNU cross compiling tools available in your path. In this case,
4568 you must set the environment variable CROSS_COMPILE in your shell.
4569 Note that no changes to the Makefile or any other source files are
4570 necessary. For example using the ELDK on a 4xx CPU, please enter:
4572 $ CROSS_COMPILE=ppc_4xx-
4573 $ export CROSS_COMPILE
4575 Note: If you wish to generate Windows versions of the utilities in
4576 the tools directory you can use the MinGW toolchain
4577 (http://www.mingw.org). Set your HOST tools to the MinGW
4578 toolchain and execute 'make tools'. For example:
4580 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
4582 Binaries such as tools/mkimage.exe will be created which can
4583 be executed on computers running Windows.
4585 U-Boot is intended to be simple to build. After installing the
4586 sources you must configure U-Boot for one specific board type. This
4591 where "NAME_config" is the name of one of the existing configu-
4592 rations; see boards.cfg for supported names.
4594 Note: for some board special configuration names may exist; check if
4595 additional information is available from the board vendor; for
4596 instance, the TQM823L systems are available without (standard)
4597 or with LCD support. You can select such additional "features"
4598 when choosing the configuration, i. e.
4601 - will configure for a plain TQM823L, i. e. no LCD support
4603 make TQM823L_LCD_config
4604 - will configure for a TQM823L with U-Boot console on LCD
4609 Finally, type "make all", and you should get some working U-Boot
4610 images ready for download to / installation on your system:
4612 - "u-boot.bin" is a raw binary image
4613 - "u-boot" is an image in ELF binary format
4614 - "u-boot.srec" is in Motorola S-Record format
4616 By default the build is performed locally and the objects are saved
4617 in the source directory. One of the two methods can be used to change
4618 this behavior and build U-Boot to some external directory:
4620 1. Add O= to the make command line invocations:
4622 make O=/tmp/build distclean
4623 make O=/tmp/build NAME_config
4624 make O=/tmp/build all
4626 2. Set environment variable BUILD_DIR to point to the desired location:
4628 export BUILD_DIR=/tmp/build
4633 Note that the command line "O=" setting overrides the BUILD_DIR environment
4637 Please be aware that the Makefiles assume you are using GNU make, so
4638 for instance on NetBSD you might need to use "gmake" instead of
4642 If the system board that you have is not listed, then you will need
4643 to port U-Boot to your hardware platform. To do this, follow these
4646 1. Add a new configuration option for your board to the toplevel
4647 "boards.cfg" file, using the existing entries as examples.
4648 Follow the instructions there to keep the boards in order.
4649 2. Create a new directory to hold your board specific code. Add any
4650 files you need. In your board directory, you will need at least
4651 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
4652 3. Create a new configuration file "include/configs/<board>.h" for
4654 3. If you're porting U-Boot to a new CPU, then also create a new
4655 directory to hold your CPU specific code. Add any files you need.
4656 4. Run "make <board>_config" with your new name.
4657 5. Type "make", and you should get a working "u-boot.srec" file
4658 to be installed on your target system.
4659 6. Debug and solve any problems that might arise.
4660 [Of course, this last step is much harder than it sounds.]
4663 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
4664 ==============================================================
4666 If you have modified U-Boot sources (for instance added a new board
4667 or support for new devices, a new CPU, etc.) you are expected to
4668 provide feedback to the other developers. The feedback normally takes
4669 the form of a "patch", i. e. a context diff against a certain (latest
4670 official or latest in the git repository) version of U-Boot sources.
4672 But before you submit such a patch, please verify that your modifi-
4673 cation did not break existing code. At least make sure that *ALL* of
4674 the supported boards compile WITHOUT ANY compiler warnings. To do so,
4675 just run the "MAKEALL" script, which will configure and build U-Boot
4676 for ALL supported system. Be warned, this will take a while. You can
4677 select which (cross) compiler to use by passing a `CROSS_COMPILE'
4678 environment variable to the script, i. e. to use the ELDK cross tools
4681 CROSS_COMPILE=ppc_8xx- MAKEALL
4683 or to build on a native PowerPC system you can type
4685 CROSS_COMPILE=' ' MAKEALL
4687 When using the MAKEALL script, the default behaviour is to build
4688 U-Boot in the source directory. This location can be changed by
4689 setting the BUILD_DIR environment variable. Also, for each target
4690 built, the MAKEALL script saves two log files (<target>.ERR and
4691 <target>.MAKEALL) in the <source dir>/LOG directory. This default
4692 location can be changed by setting the MAKEALL_LOGDIR environment
4693 variable. For example:
4695 export BUILD_DIR=/tmp/build
4696 export MAKEALL_LOGDIR=/tmp/log
4697 CROSS_COMPILE=ppc_8xx- MAKEALL
4699 With the above settings build objects are saved in the /tmp/build,
4700 log files are saved in the /tmp/log and the source tree remains clean
4701 during the whole build process.
4704 See also "U-Boot Porting Guide" below.
4707 Monitor Commands - Overview:
4708 ============================
4710 go - start application at address 'addr'
4711 run - run commands in an environment variable
4712 bootm - boot application image from memory
4713 bootp - boot image via network using BootP/TFTP protocol
4714 bootz - boot zImage from memory
4715 tftpboot- boot image via network using TFTP protocol
4716 and env variables "ipaddr" and "serverip"
4717 (and eventually "gatewayip")
4718 tftpput - upload a file via network using TFTP protocol
4719 rarpboot- boot image via network using RARP/TFTP protocol
4720 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
4721 loads - load S-Record file over serial line
4722 loadb - load binary file over serial line (kermit mode)
4724 mm - memory modify (auto-incrementing)
4725 nm - memory modify (constant address)
4726 mw - memory write (fill)
4728 cmp - memory compare
4729 crc32 - checksum calculation
4730 i2c - I2C sub-system
4731 sspi - SPI utility commands
4732 base - print or set address offset
4733 printenv- print environment variables
4734 setenv - set environment variables
4735 saveenv - save environment variables to persistent storage
4736 protect - enable or disable FLASH write protection
4737 erase - erase FLASH memory
4738 flinfo - print FLASH memory information
4739 nand - NAND memory operations (see doc/README.nand)
4740 bdinfo - print Board Info structure
4741 iminfo - print header information for application image
4742 coninfo - print console devices and informations
4743 ide - IDE sub-system
4744 loop - infinite loop on address range
4745 loopw - infinite write loop on address range
4746 mtest - simple RAM test
4747 icache - enable or disable instruction cache
4748 dcache - enable or disable data cache
4749 reset - Perform RESET of the CPU
4750 echo - echo args to console
4751 version - print monitor version
4752 help - print online help
4753 ? - alias for 'help'
4756 Monitor Commands - Detailed Description:
4757 ========================================
4761 For now: just type "help <command>".
4764 Environment Variables:
4765 ======================
4767 U-Boot supports user configuration using Environment Variables which
4768 can be made persistent by saving to Flash memory.
4770 Environment Variables are set using "setenv", printed using
4771 "printenv", and saved to Flash using "saveenv". Using "setenv"
4772 without a value can be used to delete a variable from the
4773 environment. As long as you don't save the environment you are
4774 working with an in-memory copy. In case the Flash area containing the
4775 environment is erased by accident, a default environment is provided.
4777 Some configuration options can be set using Environment Variables.
4779 List of environment variables (most likely not complete):
4781 baudrate - see CONFIG_BAUDRATE
4783 bootdelay - see CONFIG_BOOTDELAY
4785 bootcmd - see CONFIG_BOOTCOMMAND
4787 bootargs - Boot arguments when booting an RTOS image
4789 bootfile - Name of the image to load with TFTP
4791 bootm_low - Memory range available for image processing in the bootm
4792 command can be restricted. This variable is given as
4793 a hexadecimal number and defines lowest address allowed
4794 for use by the bootm command. See also "bootm_size"
4795 environment variable. Address defined by "bootm_low" is
4796 also the base of the initial memory mapping for the Linux
4797 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
4800 bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
4801 This variable is given as a hexadecimal number and it
4802 defines the size of the memory region starting at base
4803 address bootm_low that is accessible by the Linux kernel
4804 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used
4805 as the default value if it is defined, and bootm_size is
4808 bootm_size - Memory range available for image processing in the bootm
4809 command can be restricted. This variable is given as
4810 a hexadecimal number and defines the size of the region
4811 allowed for use by the bootm command. See also "bootm_low"
4812 environment variable.
4814 updatefile - Location of the software update file on a TFTP server, used
4815 by the automatic software update feature. Please refer to
4816 documentation in doc/README.update for more details.
4818 autoload - if set to "no" (any string beginning with 'n'),
4819 "bootp" will just load perform a lookup of the
4820 configuration from the BOOTP server, but not try to
4821 load any image using TFTP
4823 autostart - if set to "yes", an image loaded using the "bootp",
4824 "rarpboot", "tftpboot" or "diskboot" commands will
4825 be automatically started (by internally calling
4828 If set to "no", a standalone image passed to the
4829 "bootm" command will be copied to the load address
4830 (and eventually uncompressed), but NOT be started.
4831 This can be used to load and uncompress arbitrary
4834 fdt_high - if set this restricts the maximum address that the
4835 flattened device tree will be copied into upon boot.
4836 For example, if you have a system with 1 GB memory
4837 at physical address 0x10000000, while Linux kernel
4838 only recognizes the first 704 MB as low memory, you
4839 may need to set fdt_high as 0x3C000000 to have the
4840 device tree blob be copied to the maximum address
4841 of the 704 MB low memory, so that Linux kernel can
4842 access it during the boot procedure.
4844 If this is set to the special value 0xFFFFFFFF then
4845 the fdt will not be copied at all on boot. For this
4846 to work it must reside in writable memory, have
4847 sufficient padding on the end of it for u-boot to
4848 add the information it needs into it, and the memory
4849 must be accessible by the kernel.
4851 fdtcontroladdr- if set this is the address of the control flattened
4852 device tree used by U-Boot when CONFIG_OF_CONTROL is
4855 i2cfast - (PPC405GP|PPC405EP only)
4856 if set to 'y' configures Linux I2C driver for fast
4857 mode (400kHZ). This environment variable is used in
4858 initialization code. So, for changes to be effective
4859 it must be saved and board must be reset.
4861 initrd_high - restrict positioning of initrd images:
4862 If this variable is not set, initrd images will be
4863 copied to the highest possible address in RAM; this
4864 is usually what you want since it allows for
4865 maximum initrd size. If for some reason you want to
4866 make sure that the initrd image is loaded below the
4867 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
4868 variable to a value of "no" or "off" or "0".
4869 Alternatively, you can set it to a maximum upper
4870 address to use (U-Boot will still check that it
4871 does not overwrite the U-Boot stack and data).
4873 For instance, when you have a system with 16 MB
4874 RAM, and want to reserve 4 MB from use by Linux,
4875 you can do this by adding "mem=12M" to the value of
4876 the "bootargs" variable. However, now you must make
4877 sure that the initrd image is placed in the first
4878 12 MB as well - this can be done with
4880 setenv initrd_high 00c00000
4882 If you set initrd_high to 0xFFFFFFFF, this is an
4883 indication to U-Boot that all addresses are legal
4884 for the Linux kernel, including addresses in flash
4885 memory. In this case U-Boot will NOT COPY the
4886 ramdisk at all. This may be useful to reduce the
4887 boot time on your system, but requires that this
4888 feature is supported by your Linux kernel.
4890 ipaddr - IP address; needed for tftpboot command
4892 loadaddr - Default load address for commands like "bootp",
4893 "rarpboot", "tftpboot", "loadb" or "diskboot"
4895 loads_echo - see CONFIG_LOADS_ECHO
4897 serverip - TFTP server IP address; needed for tftpboot command
4899 bootretry - see CONFIG_BOOT_RETRY_TIME
4901 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
4903 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
4905 ethprime - controls which interface is used first.
4907 ethact - controls which interface is currently active.
4908 For example you can do the following
4910 => setenv ethact FEC
4911 => ping 192.168.0.1 # traffic sent on FEC
4912 => setenv ethact SCC
4913 => ping 10.0.0.1 # traffic sent on SCC
4915 ethrotate - When set to "no" U-Boot does not go through all
4916 available network interfaces.
4917 It just stays at the currently selected interface.
4919 netretry - When set to "no" each network operation will
4920 either succeed or fail without retrying.
4921 When set to "once" the network operation will
4922 fail when all the available network interfaces
4923 are tried once without success.
4924 Useful on scripts which control the retry operation
4927 npe_ucode - set load address for the NPE microcode
4929 silent_linux - If set then linux will be told to boot silently, by
4930 changing the console to be empty. If "yes" it will be
4931 made silent. If "no" it will not be made silent. If
4932 unset, then it will be made silent if the U-Boot console
4935 tftpsrcport - If this is set, the value is used for TFTP's
4938 tftpdstport - If this is set, the value is used for TFTP's UDP
4939 destination port instead of the Well Know Port 69.
4941 tftpblocksize - Block size to use for TFTP transfers; if not set,
4942 we use the TFTP server's default block size
4944 tftptimeout - Retransmission timeout for TFTP packets (in milli-
4945 seconds, minimum value is 1000 = 1 second). Defines
4946 when a packet is considered to be lost so it has to
4947 be retransmitted. The default is 5000 = 5 seconds.
4948 Lowering this value may make downloads succeed
4949 faster in networks with high packet loss rates or
4950 with unreliable TFTP servers.
4952 vlan - When set to a value < 4095 the traffic over
4953 Ethernet is encapsulated/received over 802.1q
4956 The following image location variables contain the location of images
4957 used in booting. The "Image" column gives the role of the image and is
4958 not an environment variable name. The other columns are environment
4959 variable names. "File Name" gives the name of the file on a TFTP
4960 server, "RAM Address" gives the location in RAM the image will be
4961 loaded to, and "Flash Location" gives the image's address in NOR
4962 flash or offset in NAND flash.
4964 *Note* - these variables don't have to be defined for all boards, some
4965 boards currenlty use other variables for these purposes, and some
4966 boards use these variables for other purposes.
4968 Image File Name RAM Address Flash Location
4969 ----- --------- ----------- --------------
4970 u-boot u-boot u-boot_addr_r u-boot_addr
4971 Linux kernel bootfile kernel_addr_r kernel_addr
4972 device tree blob fdtfile fdt_addr_r fdt_addr
4973 ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr
4975 The following environment variables may be used and automatically
4976 updated by the network boot commands ("bootp" and "rarpboot"),
4977 depending the information provided by your boot server:
4979 bootfile - see above
4980 dnsip - IP address of your Domain Name Server
4981 dnsip2 - IP address of your secondary Domain Name Server
4982 gatewayip - IP address of the Gateway (Router) to use
4983 hostname - Target hostname
4985 netmask - Subnet Mask
4986 rootpath - Pathname of the root filesystem on the NFS server
4987 serverip - see above
4990 There are two special Environment Variables:
4992 serial# - contains hardware identification information such
4993 as type string and/or serial number
4994 ethaddr - Ethernet address
4996 These variables can be set only once (usually during manufacturing of
4997 the board). U-Boot refuses to delete or overwrite these variables
4998 once they have been set once.
5001 Further special Environment Variables:
5003 ver - Contains the U-Boot version string as printed
5004 with the "version" command. This variable is
5005 readonly (see CONFIG_VERSION_VARIABLE).
5008 Please note that changes to some configuration parameters may take
5009 only effect after the next boot (yes, that's just like Windoze :-).
5012 Callback functions for environment variables:
5013 ---------------------------------------------
5015 For some environment variables, the behavior of u-boot needs to change
5016 when their values are changed. This functionailty allows functions to
5017 be associated with arbitrary variables. On creation, overwrite, or
5018 deletion, the callback will provide the opportunity for some side
5019 effect to happen or for the change to be rejected.
5021 The callbacks are named and associated with a function using the
5022 U_BOOT_ENV_CALLBACK macro in your board or driver code.
5024 These callbacks are associated with variables in one of two ways. The
5025 static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC
5026 in the board configuration to a string that defines a list of
5027 associations. The list must be in the following format:
5029 entry = variable_name[:callback_name]
5032 If the callback name is not specified, then the callback is deleted.
5033 Spaces are also allowed anywhere in the list.
5035 Callbacks can also be associated by defining the ".callbacks" variable
5036 with the same list format above. Any association in ".callbacks" will
5037 override any association in the static list. You can define
5038 CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the
5039 ".callbacks" envirnoment variable in the default or embedded environment.
5042 Command Line Parsing:
5043 =====================
5045 There are two different command line parsers available with U-Boot:
5046 the old "simple" one, and the much more powerful "hush" shell:
5048 Old, simple command line parser:
5049 --------------------------------
5051 - supports environment variables (through setenv / saveenv commands)
5052 - several commands on one line, separated by ';'
5053 - variable substitution using "... ${name} ..." syntax
5054 - special characters ('$', ';') can be escaped by prefixing with '\',
5056 setenv bootcmd bootm \${address}
5057 - You can also escape text by enclosing in single apostrophes, for example:
5058 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
5063 - similar to Bourne shell, with control structures like
5064 if...then...else...fi, for...do...done; while...do...done,
5065 until...do...done, ...
5066 - supports environment ("global") variables (through setenv / saveenv
5067 commands) and local shell variables (through standard shell syntax
5068 "name=value"); only environment variables can be used with "run"
5074 (1) If a command line (or an environment variable executed by a "run"
5075 command) contains several commands separated by semicolon, and
5076 one of these commands fails, then the remaining commands will be
5079 (2) If you execute several variables with one call to run (i. e.
5080 calling run with a list of variables as arguments), any failing
5081 command will cause "run" to terminate, i. e. the remaining
5082 variables are not executed.
5084 Note for Redundant Ethernet Interfaces:
5085 =======================================
5087 Some boards come with redundant Ethernet interfaces; U-Boot supports
5088 such configurations and is capable of automatic selection of a
5089 "working" interface when needed. MAC assignment works as follows:
5091 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
5092 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
5093 "eth1addr" (=>eth1), "eth2addr", ...
5095 If the network interface stores some valid MAC address (for instance
5096 in SROM), this is used as default address if there is NO correspon-
5097 ding setting in the environment; if the corresponding environment
5098 variable is set, this overrides the settings in the card; that means:
5100 o If the SROM has a valid MAC address, and there is no address in the
5101 environment, the SROM's address is used.
5103 o If there is no valid address in the SROM, and a definition in the
5104 environment exists, then the value from the environment variable is
5107 o If both the SROM and the environment contain a MAC address, and
5108 both addresses are the same, this MAC address is used.
5110 o If both the SROM and the environment contain a MAC address, and the
5111 addresses differ, the value from the environment is used and a
5114 o If neither SROM nor the environment contain a MAC address, an error
5117 If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
5118 will be programmed into hardware as part of the initialization process. This
5119 may be skipped by setting the appropriate 'ethmacskip' environment variable.
5120 The naming convention is as follows:
5121 "ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
5126 U-Boot is capable of booting (and performing other auxiliary operations on)
5127 images in two formats:
5129 New uImage format (FIT)
5130 -----------------------
5132 Flexible and powerful format based on Flattened Image Tree -- FIT (similar
5133 to Flattened Device Tree). It allows the use of images with multiple
5134 components (several kernels, ramdisks, etc.), with contents protected by
5135 SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
5141 Old image format is based on binary files which can be basically anything,
5142 preceded by a special header; see the definitions in include/image.h for
5143 details; basically, the header defines the following image properties:
5145 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
5146 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
5147 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
5148 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
5150 * Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86,
5151 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
5152 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC).
5153 * Compression Type (uncompressed, gzip, bzip2)
5159 The header is marked by a special Magic Number, and both the header
5160 and the data portions of the image are secured against corruption by
5167 Although U-Boot should support any OS or standalone application
5168 easily, the main focus has always been on Linux during the design of
5171 U-Boot includes many features that so far have been part of some
5172 special "boot loader" code within the Linux kernel. Also, any
5173 "initrd" images to be used are no longer part of one big Linux image;
5174 instead, kernel and "initrd" are separate images. This implementation
5175 serves several purposes:
5177 - the same features can be used for other OS or standalone
5178 applications (for instance: using compressed images to reduce the
5179 Flash memory footprint)
5181 - it becomes much easier to port new Linux kernel versions because
5182 lots of low-level, hardware dependent stuff are done by U-Boot
5184 - the same Linux kernel image can now be used with different "initrd"
5185 images; of course this also means that different kernel images can
5186 be run with the same "initrd". This makes testing easier (you don't
5187 have to build a new "zImage.initrd" Linux image when you just
5188 change a file in your "initrd"). Also, a field-upgrade of the
5189 software is easier now.
5195 Porting Linux to U-Boot based systems:
5196 ---------------------------------------
5198 U-Boot cannot save you from doing all the necessary modifications to
5199 configure the Linux device drivers for use with your target hardware
5200 (no, we don't intend to provide a full virtual machine interface to
5203 But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
5205 Just make sure your machine specific header file (for instance
5206 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
5207 Information structure as we define in include/asm-<arch>/u-boot.h,
5208 and make sure that your definition of IMAP_ADDR uses the same value
5209 as your U-Boot configuration in CONFIG_SYS_IMMR.
5212 Configuring the Linux kernel:
5213 -----------------------------
5215 No specific requirements for U-Boot. Make sure you have some root
5216 device (initial ramdisk, NFS) for your target system.
5219 Building a Linux Image:
5220 -----------------------
5222 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
5223 not used. If you use recent kernel source, a new build target
5224 "uImage" will exist which automatically builds an image usable by
5225 U-Boot. Most older kernels also have support for a "pImage" target,
5226 which was introduced for our predecessor project PPCBoot and uses a
5227 100% compatible format.
5236 The "uImage" build target uses a special tool (in 'tools/mkimage') to
5237 encapsulate a compressed Linux kernel image with header information,
5238 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
5240 * build a standard "vmlinux" kernel image (in ELF binary format):
5242 * convert the kernel into a raw binary image:
5244 ${CROSS_COMPILE}-objcopy -O binary \
5245 -R .note -R .comment \
5246 -S vmlinux linux.bin
5248 * compress the binary image:
5252 * package compressed binary image for U-Boot:
5254 mkimage -A ppc -O linux -T kernel -C gzip \
5255 -a 0 -e 0 -n "Linux Kernel Image" \
5256 -d linux.bin.gz uImage
5259 The "mkimage" tool can also be used to create ramdisk images for use
5260 with U-Boot, either separated from the Linux kernel image, or
5261 combined into one file. "mkimage" encapsulates the images with a 64
5262 byte header containing information about target architecture,
5263 operating system, image type, compression method, entry points, time
5264 stamp, CRC32 checksums, etc.
5266 "mkimage" can be called in two ways: to verify existing images and
5267 print the header information, or to build new images.
5269 In the first form (with "-l" option) mkimage lists the information
5270 contained in the header of an existing U-Boot image; this includes
5271 checksum verification:
5273 tools/mkimage -l image
5274 -l ==> list image header information
5276 The second form (with "-d" option) is used to build a U-Boot image
5277 from a "data file" which is used as image payload:
5279 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
5280 -n name -d data_file image
5281 -A ==> set architecture to 'arch'
5282 -O ==> set operating system to 'os'
5283 -T ==> set image type to 'type'
5284 -C ==> set compression type 'comp'
5285 -a ==> set load address to 'addr' (hex)
5286 -e ==> set entry point to 'ep' (hex)
5287 -n ==> set image name to 'name'
5288 -d ==> use image data from 'datafile'
5290 Right now, all Linux kernels for PowerPC systems use the same load
5291 address (0x00000000), but the entry point address depends on the
5294 - 2.2.x kernels have the entry point at 0x0000000C,
5295 - 2.3.x and later kernels have the entry point at 0x00000000.
5297 So a typical call to build a U-Boot image would read:
5299 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
5300 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
5301 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
5302 > examples/uImage.TQM850L
5303 Image Name: 2.4.4 kernel for TQM850L
5304 Created: Wed Jul 19 02:34:59 2000
5305 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5306 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
5307 Load Address: 0x00000000
5308 Entry Point: 0x00000000
5310 To verify the contents of the image (or check for corruption):
5312 -> tools/mkimage -l examples/uImage.TQM850L
5313 Image Name: 2.4.4 kernel for TQM850L
5314 Created: Wed Jul 19 02:34:59 2000
5315 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5316 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
5317 Load Address: 0x00000000
5318 Entry Point: 0x00000000
5320 NOTE: for embedded systems where boot time is critical you can trade
5321 speed for memory and install an UNCOMPRESSED image instead: this
5322 needs more space in Flash, but boots much faster since it does not
5323 need to be uncompressed:
5325 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
5326 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
5327 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
5328 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
5329 > examples/uImage.TQM850L-uncompressed
5330 Image Name: 2.4.4 kernel for TQM850L
5331 Created: Wed Jul 19 02:34:59 2000
5332 Image Type: PowerPC Linux Kernel Image (uncompressed)
5333 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
5334 Load Address: 0x00000000
5335 Entry Point: 0x00000000
5338 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
5339 when your kernel is intended to use an initial ramdisk:
5341 -> tools/mkimage -n 'Simple Ramdisk Image' \
5342 > -A ppc -O linux -T ramdisk -C gzip \
5343 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
5344 Image Name: Simple Ramdisk Image
5345 Created: Wed Jan 12 14:01:50 2000
5346 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5347 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
5348 Load Address: 0x00000000
5349 Entry Point: 0x00000000
5351 The "dumpimage" is a tool to disassemble images built by mkimage. Its "-i"
5352 option performs the converse operation of the mkimage's second form (the "-d"
5353 option). Given an image built by mkimage, the dumpimage extracts a "data file"
5356 tools/dumpimage -i image -p position data_file
5357 -i ==> extract from the 'image' a specific 'data_file', \
5358 indexed by 'position'
5361 Installing a Linux Image:
5362 -------------------------
5364 To downloading a U-Boot image over the serial (console) interface,
5365 you must convert the image to S-Record format:
5367 objcopy -I binary -O srec examples/image examples/image.srec
5369 The 'objcopy' does not understand the information in the U-Boot
5370 image header, so the resulting S-Record file will be relative to
5371 address 0x00000000. To load it to a given address, you need to
5372 specify the target address as 'offset' parameter with the 'loads'
5375 Example: install the image to address 0x40100000 (which on the
5376 TQM8xxL is in the first Flash bank):
5378 => erase 40100000 401FFFFF
5384 ## Ready for S-Record download ...
5385 ~>examples/image.srec
5386 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
5388 15989 15990 15991 15992
5389 [file transfer complete]
5391 ## Start Addr = 0x00000000
5394 You can check the success of the download using the 'iminfo' command;
5395 this includes a checksum verification so you can be sure no data
5396 corruption happened:
5400 ## Checking Image at 40100000 ...
5401 Image Name: 2.2.13 for initrd on TQM850L
5402 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5403 Data Size: 335725 Bytes = 327 kB = 0 MB
5404 Load Address: 00000000
5405 Entry Point: 0000000c
5406 Verifying Checksum ... OK
5412 The "bootm" command is used to boot an application that is stored in
5413 memory (RAM or Flash). In case of a Linux kernel image, the contents
5414 of the "bootargs" environment variable is passed to the kernel as
5415 parameters. You can check and modify this variable using the
5416 "printenv" and "setenv" commands:
5419 => printenv bootargs
5420 bootargs=root=/dev/ram
5422 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5424 => printenv bootargs
5425 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5428 ## Booting Linux kernel at 40020000 ...
5429 Image Name: 2.2.13 for NFS on TQM850L
5430 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5431 Data Size: 381681 Bytes = 372 kB = 0 MB
5432 Load Address: 00000000
5433 Entry Point: 0000000c
5434 Verifying Checksum ... OK
5435 Uncompressing Kernel Image ... OK
5436 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
5437 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5438 time_init: decrementer frequency = 187500000/60
5439 Calibrating delay loop... 49.77 BogoMIPS
5440 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
5443 If you want to boot a Linux kernel with initial RAM disk, you pass
5444 the memory addresses of both the kernel and the initrd image (PPBCOOT
5445 format!) to the "bootm" command:
5447 => imi 40100000 40200000
5449 ## Checking Image at 40100000 ...
5450 Image Name: 2.2.13 for initrd on TQM850L
5451 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5452 Data Size: 335725 Bytes = 327 kB = 0 MB
5453 Load Address: 00000000
5454 Entry Point: 0000000c
5455 Verifying Checksum ... OK
5457 ## Checking Image at 40200000 ...
5458 Image Name: Simple Ramdisk Image
5459 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5460 Data Size: 566530 Bytes = 553 kB = 0 MB
5461 Load Address: 00000000
5462 Entry Point: 00000000
5463 Verifying Checksum ... OK
5465 => bootm 40100000 40200000
5466 ## Booting Linux kernel at 40100000 ...
5467 Image Name: 2.2.13 for initrd on TQM850L
5468 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5469 Data Size: 335725 Bytes = 327 kB = 0 MB
5470 Load Address: 00000000
5471 Entry Point: 0000000c
5472 Verifying Checksum ... OK
5473 Uncompressing Kernel Image ... OK
5474 ## Loading RAMDisk Image at 40200000 ...
5475 Image Name: Simple Ramdisk Image
5476 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5477 Data Size: 566530 Bytes = 553 kB = 0 MB
5478 Load Address: 00000000
5479 Entry Point: 00000000
5480 Verifying Checksum ... OK
5481 Loading Ramdisk ... OK
5482 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
5483 Boot arguments: root=/dev/ram
5484 time_init: decrementer frequency = 187500000/60
5485 Calibrating delay loop... 49.77 BogoMIPS
5487 RAMDISK: Compressed image found at block 0
5488 VFS: Mounted root (ext2 filesystem).
5492 Boot Linux and pass a flat device tree:
5495 First, U-Boot must be compiled with the appropriate defines. See the section
5496 titled "Linux Kernel Interface" above for a more in depth explanation. The
5497 following is an example of how to start a kernel and pass an updated
5503 oft=oftrees/mpc8540ads.dtb
5504 => tftp $oftaddr $oft
5505 Speed: 1000, full duplex
5507 TFTP from server 192.168.1.1; our IP address is 192.168.1.101
5508 Filename 'oftrees/mpc8540ads.dtb'.
5509 Load address: 0x300000
5512 Bytes transferred = 4106 (100a hex)
5513 => tftp $loadaddr $bootfile
5514 Speed: 1000, full duplex
5516 TFTP from server 192.168.1.1; our IP address is 192.168.1.2
5518 Load address: 0x200000
5519 Loading:############
5521 Bytes transferred = 1029407 (fb51f hex)
5526 => bootm $loadaddr - $oftaddr
5527 ## Booting image at 00200000 ...
5528 Image Name: Linux-2.6.17-dirty
5529 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5530 Data Size: 1029343 Bytes = 1005.2 kB
5531 Load Address: 00000000
5532 Entry Point: 00000000
5533 Verifying Checksum ... OK
5534 Uncompressing Kernel Image ... OK
5535 Booting using flat device tree at 0x300000
5536 Using MPC85xx ADS machine description
5537 Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
5541 More About U-Boot Image Types:
5542 ------------------------------
5544 U-Boot supports the following image types:
5546 "Standalone Programs" are directly runnable in the environment
5547 provided by U-Boot; it is expected that (if they behave
5548 well) you can continue to work in U-Boot after return from
5549 the Standalone Program.
5550 "OS Kernel Images" are usually images of some Embedded OS which
5551 will take over control completely. Usually these programs
5552 will install their own set of exception handlers, device
5553 drivers, set up the MMU, etc. - this means, that you cannot
5554 expect to re-enter U-Boot except by resetting the CPU.
5555 "RAMDisk Images" are more or less just data blocks, and their
5556 parameters (address, size) are passed to an OS kernel that is
5558 "Multi-File Images" contain several images, typically an OS
5559 (Linux) kernel image and one or more data images like
5560 RAMDisks. This construct is useful for instance when you want
5561 to boot over the network using BOOTP etc., where the boot
5562 server provides just a single image file, but you want to get
5563 for instance an OS kernel and a RAMDisk image.
5565 "Multi-File Images" start with a list of image sizes, each
5566 image size (in bytes) specified by an "uint32_t" in network
5567 byte order. This list is terminated by an "(uint32_t)0".
5568 Immediately after the terminating 0 follow the images, one by
5569 one, all aligned on "uint32_t" boundaries (size rounded up to
5570 a multiple of 4 bytes).
5572 "Firmware Images" are binary images containing firmware (like
5573 U-Boot or FPGA images) which usually will be programmed to
5576 "Script files" are command sequences that will be executed by
5577 U-Boot's command interpreter; this feature is especially
5578 useful when you configure U-Boot to use a real shell (hush)
5579 as command interpreter.
5581 Booting the Linux zImage:
5582 -------------------------
5584 On some platforms, it's possible to boot Linux zImage. This is done
5585 using the "bootz" command. The syntax of "bootz" command is the same
5586 as the syntax of "bootm" command.
5588 Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply
5589 kernel with raw initrd images. The syntax is slightly different, the
5590 address of the initrd must be augmented by it's size, in the following
5591 format: "<initrd addres>:<initrd size>".
5597 One of the features of U-Boot is that you can dynamically load and
5598 run "standalone" applications, which can use some resources of
5599 U-Boot like console I/O functions or interrupt services.
5601 Two simple examples are included with the sources:
5606 'examples/hello_world.c' contains a small "Hello World" Demo
5607 application; it is automatically compiled when you build U-Boot.
5608 It's configured to run at address 0x00040004, so you can play with it
5612 ## Ready for S-Record download ...
5613 ~>examples/hello_world.srec
5614 1 2 3 4 5 6 7 8 9 10 11 ...
5615 [file transfer complete]
5617 ## Start Addr = 0x00040004
5619 => go 40004 Hello World! This is a test.
5620 ## Starting application at 0x00040004 ...
5631 Hit any key to exit ...
5633 ## Application terminated, rc = 0x0
5635 Another example, which demonstrates how to register a CPM interrupt
5636 handler with the U-Boot code, can be found in 'examples/timer.c'.
5637 Here, a CPM timer is set up to generate an interrupt every second.
5638 The interrupt service routine is trivial, just printing a '.'
5639 character, but this is just a demo program. The application can be
5640 controlled by the following keys:
5642 ? - print current values og the CPM Timer registers
5643 b - enable interrupts and start timer
5644 e - stop timer and disable interrupts
5645 q - quit application
5648 ## Ready for S-Record download ...
5649 ~>examples/timer.srec
5650 1 2 3 4 5 6 7 8 9 10 11 ...
5651 [file transfer complete]
5653 ## Start Addr = 0x00040004
5656 ## Starting application at 0x00040004 ...
5659 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
5662 [q, b, e, ?] Set interval 1000000 us
5665 [q, b, e, ?] ........
5666 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
5669 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
5672 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
5675 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
5677 [q, b, e, ?] ...Stopping timer
5679 [q, b, e, ?] ## Application terminated, rc = 0x0
5685 Over time, many people have reported problems when trying to use the
5686 "minicom" terminal emulation program for serial download. I (wd)
5687 consider minicom to be broken, and recommend not to use it. Under
5688 Unix, I recommend to use C-Kermit for general purpose use (and
5689 especially for kermit binary protocol download ("loadb" command), and
5690 use "cu" for S-Record download ("loads" command). See
5691 http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3.
5692 for help with kermit.
5695 Nevertheless, if you absolutely want to use it try adding this
5696 configuration to your "File transfer protocols" section:
5698 Name Program Name U/D FullScr IO-Red. Multi
5699 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
5700 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
5706 Starting at version 0.9.2, U-Boot supports NetBSD both as host
5707 (build U-Boot) and target system (boots NetBSD/mpc8xx).
5709 Building requires a cross environment; it is known to work on
5710 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
5711 need gmake since the Makefiles are not compatible with BSD make).
5712 Note that the cross-powerpc package does not install include files;
5713 attempting to build U-Boot will fail because <machine/ansi.h> is
5714 missing. This file has to be installed and patched manually:
5716 # cd /usr/pkg/cross/powerpc-netbsd/include
5718 # ln -s powerpc machine
5719 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
5720 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
5722 Native builds *don't* work due to incompatibilities between native
5723 and U-Boot include files.
5725 Booting assumes that (the first part of) the image booted is a
5726 stage-2 loader which in turn loads and then invokes the kernel
5727 proper. Loader sources will eventually appear in the NetBSD source
5728 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
5729 meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
5732 Implementation Internals:
5733 =========================
5735 The following is not intended to be a complete description of every
5736 implementation detail. However, it should help to understand the
5737 inner workings of U-Boot and make it easier to port it to custom
5741 Initial Stack, Global Data:
5742 ---------------------------
5744 The implementation of U-Boot is complicated by the fact that U-Boot
5745 starts running out of ROM (flash memory), usually without access to
5746 system RAM (because the memory controller is not initialized yet).
5747 This means that we don't have writable Data or BSS segments, and BSS
5748 is not initialized as zero. To be able to get a C environment working
5749 at all, we have to allocate at least a minimal stack. Implementation
5750 options for this are defined and restricted by the CPU used: Some CPU
5751 models provide on-chip memory (like the IMMR area on MPC8xx and
5752 MPC826x processors), on others (parts of) the data cache can be
5753 locked as (mis-) used as memory, etc.
5755 Chris Hallinan posted a good summary of these issues to the
5756 U-Boot mailing list:
5758 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
5759 From: "Chris Hallinan" <clh@net1plus.com>
5760 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
5763 Correct me if I'm wrong, folks, but the way I understand it
5764 is this: Using DCACHE as initial RAM for Stack, etc, does not
5765 require any physical RAM backing up the cache. The cleverness
5766 is that the cache is being used as a temporary supply of
5767 necessary storage before the SDRAM controller is setup. It's
5768 beyond the scope of this list to explain the details, but you
5769 can see how this works by studying the cache architecture and
5770 operation in the architecture and processor-specific manuals.
5772 OCM is On Chip Memory, which I believe the 405GP has 4K. It
5773 is another option for the system designer to use as an
5774 initial stack/RAM area prior to SDRAM being available. Either
5775 option should work for you. Using CS 4 should be fine if your
5776 board designers haven't used it for something that would
5777 cause you grief during the initial boot! It is frequently not
5780 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
5781 with your processor/board/system design. The default value
5782 you will find in any recent u-boot distribution in
5783 walnut.h should work for you. I'd set it to a value larger
5784 than your SDRAM module. If you have a 64MB SDRAM module, set
5785 it above 400_0000. Just make sure your board has no resources
5786 that are supposed to respond to that address! That code in
5787 start.S has been around a while and should work as is when
5788 you get the config right.
5793 It is essential to remember this, since it has some impact on the C
5794 code for the initialization procedures:
5796 * Initialized global data (data segment) is read-only. Do not attempt
5799 * Do not use any uninitialized global data (or implicitely initialized
5800 as zero data - BSS segment) at all - this is undefined, initiali-
5801 zation is performed later (when relocating to RAM).
5803 * Stack space is very limited. Avoid big data buffers or things like
5806 Having only the stack as writable memory limits means we cannot use
5807 normal global data to share information beween the code. But it
5808 turned out that the implementation of U-Boot can be greatly
5809 simplified by making a global data structure (gd_t) available to all
5810 functions. We could pass a pointer to this data as argument to _all_
5811 functions, but this would bloat the code. Instead we use a feature of
5812 the GCC compiler (Global Register Variables) to share the data: we
5813 place a pointer (gd) to the global data into a register which we
5814 reserve for this purpose.
5816 When choosing a register for such a purpose we are restricted by the
5817 relevant (E)ABI specifications for the current architecture, and by
5818 GCC's implementation.
5820 For PowerPC, the following registers have specific use:
5822 R2: reserved for system use
5823 R3-R4: parameter passing and return values
5824 R5-R10: parameter passing
5825 R13: small data area pointer
5829 (U-Boot also uses R12 as internal GOT pointer. r12
5830 is a volatile register so r12 needs to be reset when
5831 going back and forth between asm and C)
5833 ==> U-Boot will use R2 to hold a pointer to the global data
5835 Note: on PPC, we could use a static initializer (since the
5836 address of the global data structure is known at compile time),
5837 but it turned out that reserving a register results in somewhat
5838 smaller code - although the code savings are not that big (on
5839 average for all boards 752 bytes for the whole U-Boot image,
5840 624 text + 127 data).
5842 On Blackfin, the normal C ABI (except for P3) is followed as documented here:
5843 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface
5845 ==> U-Boot will use P3 to hold a pointer to the global data
5847 On ARM, the following registers are used:
5849 R0: function argument word/integer result
5850 R1-R3: function argument word
5851 R9: platform specific
5852 R10: stack limit (used only if stack checking is enabled)
5853 R11: argument (frame) pointer
5854 R12: temporary workspace
5857 R15: program counter
5859 ==> U-Boot will use R9 to hold a pointer to the global data
5861 Note: on ARM, only R_ARM_RELATIVE relocations are supported.
5863 On Nios II, the ABI is documented here:
5864 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
5866 ==> U-Boot will use gp to hold a pointer to the global data
5868 Note: on Nios II, we give "-G0" option to gcc and don't use gp
5869 to access small data sections, so gp is free.
5871 On NDS32, the following registers are used:
5873 R0-R1: argument/return
5875 R15: temporary register for assembler
5876 R16: trampoline register
5877 R28: frame pointer (FP)
5878 R29: global pointer (GP)
5879 R30: link register (LP)
5880 R31: stack pointer (SP)
5881 PC: program counter (PC)
5883 ==> U-Boot will use R10 to hold a pointer to the global data
5885 NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
5886 or current versions of GCC may "optimize" the code too much.
5891 U-Boot runs in system state and uses physical addresses, i.e. the
5892 MMU is not used either for address mapping nor for memory protection.
5894 The available memory is mapped to fixed addresses using the memory
5895 controller. In this process, a contiguous block is formed for each
5896 memory type (Flash, SDRAM, SRAM), even when it consists of several
5897 physical memory banks.
5899 U-Boot is installed in the first 128 kB of the first Flash bank (on
5900 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
5901 booting and sizing and initializing DRAM, the code relocates itself
5902 to the upper end of DRAM. Immediately below the U-Boot code some
5903 memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
5904 configuration setting]. Below that, a structure with global Board
5905 Info data is placed, followed by the stack (growing downward).
5907 Additionally, some exception handler code is copied to the low 8 kB
5908 of DRAM (0x00000000 ... 0x00001FFF).
5910 So a typical memory configuration with 16 MB of DRAM could look like
5913 0x0000 0000 Exception Vector code
5916 0x0000 2000 Free for Application Use
5922 0x00FB FF20 Monitor Stack (Growing downward)
5923 0x00FB FFAC Board Info Data and permanent copy of global data
5924 0x00FC 0000 Malloc Arena
5927 0x00FE 0000 RAM Copy of Monitor Code
5928 ... eventually: LCD or video framebuffer
5929 ... eventually: pRAM (Protected RAM - unchanged by reset)
5930 0x00FF FFFF [End of RAM]
5933 System Initialization:
5934 ----------------------
5936 In the reset configuration, U-Boot starts at the reset entry point
5937 (on most PowerPC systems at address 0x00000100). Because of the reset
5938 configuration for CS0# this is a mirror of the onboard Flash memory.
5939 To be able to re-map memory U-Boot then jumps to its link address.
5940 To be able to implement the initialization code in C, a (small!)
5941 initial stack is set up in the internal Dual Ported RAM (in case CPUs
5942 which provide such a feature like MPC8xx or MPC8260), or in a locked
5943 part of the data cache. After that, U-Boot initializes the CPU core,
5944 the caches and the SIU.
5946 Next, all (potentially) available memory banks are mapped using a
5947 preliminary mapping. For example, we put them on 512 MB boundaries
5948 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
5949 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
5950 programmed for SDRAM access. Using the temporary configuration, a
5951 simple memory test is run that determines the size of the SDRAM
5954 When there is more than one SDRAM bank, and the banks are of
5955 different size, the largest is mapped first. For equal size, the first
5956 bank (CS2#) is mapped first. The first mapping is always for address
5957 0x00000000, with any additional banks following immediately to create
5958 contiguous memory starting from 0.
5960 Then, the monitor installs itself at the upper end of the SDRAM area
5961 and allocates memory for use by malloc() and for the global Board
5962 Info data; also, the exception vector code is copied to the low RAM
5963 pages, and the final stack is set up.
5965 Only after this relocation will you have a "normal" C environment;
5966 until that you are restricted in several ways, mostly because you are
5967 running from ROM, and because the code will have to be relocated to a
5971 U-Boot Porting Guide:
5972 ----------------------
5974 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
5978 int main(int argc, char *argv[])
5980 sighandler_t no_more_time;
5982 signal(SIGALRM, no_more_time);
5983 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
5985 if (available_money > available_manpower) {
5986 Pay consultant to port U-Boot;
5990 Download latest U-Boot source;
5992 Subscribe to u-boot mailing list;
5995 email("Hi, I am new to U-Boot, how do I get started?");
5998 Read the README file in the top level directory;
5999 Read http://www.denx.de/twiki/bin/view/DULG/Manual;
6000 Read applicable doc/*.README;
6001 Read the source, Luke;
6002 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
6005 if (available_money > toLocalCurrency ($2500))
6008 Add a lot of aggravation and time;
6010 if (a similar board exists) { /* hopefully... */
6011 cp -a board/<similar> board/<myboard>
6012 cp include/configs/<similar>.h include/configs/<myboard>.h
6014 Create your own board support subdirectory;
6015 Create your own board include/configs/<myboard>.h file;
6017 Edit new board/<myboard> files
6018 Edit new include/configs/<myboard>.h
6023 Add / modify source code;
6027 email("Hi, I am having problems...");
6029 Send patch file to the U-Boot email list;
6030 if (reasonable critiques)
6031 Incorporate improvements from email list code review;
6033 Defend code as written;
6039 void no_more_time (int sig)
6048 All contributions to U-Boot should conform to the Linux kernel
6049 coding style; see the file "Documentation/CodingStyle" and the script
6050 "scripts/Lindent" in your Linux kernel source directory.
6052 Source files originating from a different project (for example the
6053 MTD subsystem) are generally exempt from these guidelines and are not
6054 reformated to ease subsequent migration to newer versions of those
6057 Please note that U-Boot is implemented in C (and to some small parts in
6058 Assembler); no C++ is used, so please do not use C++ style comments (//)
6061 Please also stick to the following formatting rules:
6062 - remove any trailing white space
6063 - use TAB characters for indentation and vertical alignment, not spaces
6064 - make sure NOT to use DOS '\r\n' line feeds
6065 - do not add more than 2 consecutive empty lines to source files
6066 - do not add trailing empty lines to source files
6068 Submissions which do not conform to the standards may be returned
6069 with a request to reformat the changes.
6075 Since the number of patches for U-Boot is growing, we need to
6076 establish some rules. Submissions which do not conform to these rules
6077 may be rejected, even when they contain important and valuable stuff.
6079 Please see http://www.denx.de/wiki/U-Boot/Patches for details.
6081 Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
6082 see http://lists.denx.de/mailman/listinfo/u-boot
6084 When you send a patch, please include the following information with
6087 * For bug fixes: a description of the bug and how your patch fixes
6088 this bug. Please try to include a way of demonstrating that the
6089 patch actually fixes something.
6091 * For new features: a description of the feature and your
6094 * A CHANGELOG entry as plaintext (separate from the patch)
6096 * For major contributions, your entry to the CREDITS file
6098 * When you add support for a new board, don't forget to add a
6099 maintainer e-mail address to the boards.cfg file, too.
6101 * If your patch adds new configuration options, don't forget to
6102 document these in the README file.
6104 * The patch itself. If you are using git (which is *strongly*
6105 recommended) you can easily generate the patch using the
6106 "git format-patch". If you then use "git send-email" to send it to
6107 the U-Boot mailing list, you will avoid most of the common problems
6108 with some other mail clients.
6110 If you cannot use git, use "diff -purN OLD NEW". If your version of
6111 diff does not support these options, then get the latest version of
6114 The current directory when running this command shall be the parent
6115 directory of the U-Boot source tree (i. e. please make sure that
6116 your patch includes sufficient directory information for the
6119 We prefer patches as plain text. MIME attachments are discouraged,
6120 and compressed attachments must not be used.
6122 * If one logical set of modifications affects or creates several
6123 files, all these changes shall be submitted in a SINGLE patch file.
6125 * Changesets that contain different, unrelated modifications shall be
6126 submitted as SEPARATE patches, one patch per changeset.
6131 * Before sending the patch, run the MAKEALL script on your patched
6132 source tree and make sure that no errors or warnings are reported
6133 for any of the boards.
6135 * Keep your modifications to the necessary minimum: A patch
6136 containing several unrelated changes or arbitrary reformats will be
6137 returned with a request to re-formatting / split it.
6139 * If you modify existing code, make sure that your new code does not
6140 add to the memory footprint of the code ;-) Small is beautiful!
6141 When adding new features, these should compile conditionally only
6142 (using #ifdef), and the resulting code with the new feature
6143 disabled must not need more memory than the old code without your
6146 * Remember that there is a size limit of 100 kB per message on the
6147 u-boot mailing list. Bigger patches will be moderated. If they are
6148 reasonable and not too big, they will be acknowledged. But patches
6149 bigger than the size limit should be avoided.
projects / karo-tx-uboot.git / blob