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 /ixp Files specific to Intel XScale IXP CPUs
145 /pxa Files specific to Intel XScale PXA CPUs
146 /sa1100 Files specific to Intel StrongARM SA1100 CPUs
147 /lib Architecture specific library files
148 /avr32 Files generic to AVR32 architecture
149 /cpu CPU specific files
150 /lib Architecture specific library files
151 /blackfin Files generic to Analog Devices Blackfin architecture
152 /cpu CPU specific files
153 /lib Architecture specific library files
154 /m68k Files generic to m68k architecture
155 /cpu CPU specific files
156 /mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs
157 /mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs
158 /mcf532x Files specific to Freescale ColdFire MCF5329 CPUs
159 /mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs
160 /mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs
161 /lib Architecture specific library files
162 /microblaze Files generic to microblaze architecture
163 /cpu CPU specific files
164 /lib Architecture specific library files
165 /mips Files generic to MIPS architecture
166 /cpu CPU specific files
167 /mips32 Files specific to MIPS32 CPUs
168 /xburst Files specific to Ingenic XBurst CPUs
169 /lib Architecture specific library files
170 /nds32 Files generic to NDS32 architecture
171 /cpu CPU specific files
172 /n1213 Files specific to Andes Technology N1213 CPUs
173 /lib Architecture specific library files
174 /nios2 Files generic to Altera NIOS2 architecture
175 /cpu CPU specific files
176 /lib Architecture specific library files
177 /openrisc Files generic to OpenRISC architecture
178 /cpu CPU specific files
179 /lib Architecture specific library files
180 /powerpc Files generic to PowerPC architecture
181 /cpu CPU specific files
182 /74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs
183 /mpc5xx Files specific to Freescale MPC5xx CPUs
184 /mpc5xxx Files specific to Freescale MPC5xxx CPUs
185 /mpc8xx Files specific to Freescale MPC8xx CPUs
186 /mpc824x Files specific to Freescale MPC824x CPUs
187 /mpc8260 Files specific to Freescale MPC8260 CPUs
188 /mpc85xx Files specific to Freescale MPC85xx CPUs
189 /ppc4xx Files specific to AMCC PowerPC 4xx CPUs
190 /lib Architecture specific library files
191 /sh Files generic to SH architecture
192 /cpu CPU specific files
193 /sh2 Files specific to sh2 CPUs
194 /sh3 Files specific to sh3 CPUs
195 /sh4 Files specific to sh4 CPUs
196 /lib Architecture specific library files
197 /sparc Files generic to SPARC architecture
198 /cpu CPU specific files
199 /leon2 Files specific to Gaisler LEON2 SPARC CPU
200 /leon3 Files specific to Gaisler LEON3 SPARC CPU
201 /lib Architecture specific library files
202 /x86 Files generic to x86 architecture
203 /cpu CPU specific files
204 /lib Architecture specific library files
205 /api Machine/arch independent API for external apps
206 /board Board dependent files
207 /common Misc architecture independent functions
208 /disk Code for disk drive partition handling
209 /doc Documentation (don't expect too much)
210 /drivers Commonly used device drivers
211 /dts Contains Makefile for building internal U-Boot fdt.
212 /examples Example code for standalone applications, etc.
213 /fs Filesystem code (cramfs, ext2, jffs2, etc.)
214 /include Header Files
215 /lib Files generic to all architectures
216 /libfdt Library files to support flattened device trees
217 /lzma Library files to support LZMA decompression
218 /lzo Library files to support LZO decompression
220 /post Power On Self Test
221 /spl Secondary Program Loader framework
222 /tools Tools to build S-Record or U-Boot images, etc.
224 Software Configuration:
225 =======================
227 Configuration is usually done using C preprocessor defines; the
228 rationale behind that is to avoid dead code whenever possible.
230 There are two classes of configuration variables:
232 * Configuration _OPTIONS_:
233 These are selectable by the user and have names beginning with
236 * Configuration _SETTINGS_:
237 These depend on the hardware etc. and should not be meddled with if
238 you don't know what you're doing; they have names beginning with
241 Later we will add a configuration tool - probably similar to or even
242 identical to what's used for the Linux kernel. Right now, we have to
243 do the configuration by hand, which means creating some symbolic
244 links and editing some configuration files. We use the TQM8xxL boards
248 Selection of Processor Architecture and Board Type:
249 ---------------------------------------------------
251 For all supported boards there are ready-to-use default
252 configurations available; just type "make <board_name>_config".
254 Example: For a TQM823L module type:
259 For the Cogent platform, you need to specify the CPU type as well;
260 e.g. "make cogent_mpc8xx_config". And also configure the cogent
261 directory according to the instructions in cogent/README.
264 Configuration Options:
265 ----------------------
267 Configuration depends on the combination of board and CPU type; all
268 such information is kept in a configuration file
269 "include/configs/<board_name>.h".
271 Example: For a TQM823L module, all configuration settings are in
272 "include/configs/TQM823L.h".
275 Many of the options are named exactly as the corresponding Linux
276 kernel configuration options. The intention is to make it easier to
277 build a config tool - later.
280 The following options need to be configured:
282 - CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
284 - Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
286 - CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined)
287 Define exactly one, e.g. CONFIG_ATSTK1002
289 - CPU Module Type: (if CONFIG_COGENT is defined)
290 Define exactly one of
292 --- FIXME --- not tested yet:
293 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
294 CONFIG_CMA287_23, CONFIG_CMA287_50
296 - Motherboard Type: (if CONFIG_COGENT is defined)
297 Define exactly one of
298 CONFIG_CMA101, CONFIG_CMA102
300 - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
301 Define one or more of
304 - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
305 Define one or more of
306 CONFIG_LCD_HEARTBEAT - update a character position on
307 the LCD display every second with
310 - Board flavour: (if CONFIG_MPC8260ADS is defined)
313 CONFIG_SYS_8260ADS - original MPC8260ADS
314 CONFIG_SYS_8266ADS - MPC8266ADS
315 CONFIG_SYS_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR
316 CONFIG_SYS_8272ADS - MPC8272ADS
318 - Marvell Family Member
319 CONFIG_SYS_MVFS - define it if you want to enable
320 multiple fs option at one time
321 for marvell soc family
323 - MPC824X Family Member (if CONFIG_MPC824X is defined)
324 Define exactly one of
325 CONFIG_MPC8240, CONFIG_MPC8245
327 - 8xx CPU Options: (if using an MPC8xx CPU)
328 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if
329 get_gclk_freq() cannot work
330 e.g. if there is no 32KHz
331 reference PIT/RTC clock
332 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK
335 - 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
336 CONFIG_SYS_8xx_CPUCLK_MIN
337 CONFIG_SYS_8xx_CPUCLK_MAX
338 CONFIG_8xx_CPUCLK_DEFAULT
339 See doc/README.MPC866
341 CONFIG_SYS_MEASURE_CPUCLK
343 Define this to measure the actual CPU clock instead
344 of relying on the correctness of the configured
345 values. Mostly useful for board bringup to make sure
346 the PLL is locked at the intended frequency. Note
347 that this requires a (stable) reference clock (32 kHz
348 RTC clock or CONFIG_SYS_8XX_XIN)
350 CONFIG_SYS_DELAYED_ICACHE
352 Define this option if you want to enable the
353 ICache only when Code runs from RAM.
358 Specifies that the core is a 64-bit PowerPC implementation (implements
359 the "64" category of the Power ISA). This is necessary for ePAPR
360 compliance, among other possible reasons.
362 CONFIG_SYS_FSL_TBCLK_DIV
364 Defines the core time base clock divider ratio compared to the
365 system clock. On most PQ3 devices this is 8, on newer QorIQ
366 devices it can be 16 or 32. The ratio varies from SoC to Soc.
368 CONFIG_SYS_FSL_PCIE_COMPAT
370 Defines the string to utilize when trying to match PCIe device
371 tree nodes for the given platform.
373 CONFIG_SYS_PPC_E500_DEBUG_TLB
375 Enables a temporary TLB entry to be used during boot to work
376 around limitations in e500v1 and e500v2 external debugger
377 support. This reduces the portions of the boot code where
378 breakpoints and single stepping do not work. The value of this
379 symbol should be set to the TLB1 entry to be used for this
382 CONFIG_SYS_FSL_ERRATUM_A004510
384 Enables a workaround for erratum A004510. If set,
385 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and
386 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set.
388 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV
389 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional)
391 Defines one or two SoC revisions (low 8 bits of SVR)
392 for which the A004510 workaround should be applied.
394 The rest of SVR is either not relevant to the decision
395 of whether the erratum is present (e.g. p2040 versus
396 p2041) or is implied by the build target, which controls
397 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set.
399 See Freescale App Note 4493 for more information about
402 CONFIG_A003399_NOR_WORKAROUND
403 Enables a workaround for IFC erratum A003399. It is only
404 requred during NOR boot.
406 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY
408 This is the value to write into CCSR offset 0x18600
409 according to the A004510 workaround.
411 CONFIG_SYS_FSL_DSP_DDR_ADDR
412 This value denotes start offset of DDR memory which is
413 connected exclusively to the DSP cores.
415 CONFIG_SYS_FSL_DSP_M2_RAM_ADDR
416 This value denotes start offset of M2 memory
417 which is directly connected to the DSP core.
419 CONFIG_SYS_FSL_DSP_M3_RAM_ADDR
420 This value denotes start offset of M3 memory which is directly
421 connected to the DSP core.
423 CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT
424 This value denotes start offset of DSP CCSR space.
426 CONFIG_SYS_FSL_DDR_EMU
427 Specify emulator support for DDR. Some DDR features such as
428 deskew training are not available.
430 - Generic CPU options:
431 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN
433 Defines the endianess of the CPU. Implementation of those
434 values is arch specific.
436 - Intel Monahans options:
437 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO
439 Defines the Monahans run mode to oscillator
440 ratio. Valid values are 8, 16, 24, 31. The core
441 frequency is this value multiplied by 13 MHz.
443 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO
445 Defines the Monahans turbo mode to oscillator
446 ratio. Valid values are 1 (default if undefined) and
447 2. The core frequency as calculated above is multiplied
451 CONFIG_SYS_INIT_SP_OFFSET
453 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack
454 pointer. This is needed for the temporary stack before
457 CONFIG_SYS_MIPS_CACHE_MODE
459 Cache operation mode for the MIPS CPU.
460 See also arch/mips/include/asm/mipsregs.h.
462 CONF_CM_CACHABLE_NO_WA
465 CONF_CM_CACHABLE_NONCOHERENT
469 CONF_CM_CACHABLE_ACCELERATED
471 CONFIG_SYS_XWAY_EBU_BOOTCFG
473 Special option for Lantiq XWAY SoCs for booting from NOR flash.
474 See also arch/mips/cpu/mips32/start.S.
476 CONFIG_XWAY_SWAP_BYTES
478 Enable compilation of tools/xway-swap-bytes needed for Lantiq
479 XWAY SoCs for booting from NOR flash. The U-Boot image needs to
480 be swapped if a flash programmer is used.
483 CONFIG_SYS_EXCEPTION_VECTORS_HIGH
485 Select high exception vectors of the ARM core, e.g., do not
486 clear the V bit of the c1 register of CP15.
488 CONFIG_SYS_THUMB_BUILD
490 Use this flag to build U-Boot using the Thumb instruction
491 set for ARM architectures. Thumb instruction set provides
492 better code density. For ARM architectures that support
493 Thumb2 this flag will result in Thumb2 code generated by
496 CONFIG_ARM_ERRATA_716044
497 CONFIG_ARM_ERRATA_742230
498 CONFIG_ARM_ERRATA_743622
499 CONFIG_ARM_ERRATA_751472
501 If set, the workarounds for these ARM errata are applied early
502 during U-Boot startup. Note that these options force the
503 workarounds to be applied; no CPU-type/version detection
504 exists, unlike the similar options in the Linux kernel. Do not
505 set these options unless they apply!
510 The frequency of the timer returned by get_timer().
511 get_timer() must operate in milliseconds and this CONFIG
512 option must be set to 1000.
514 - Linux Kernel Interface:
517 U-Boot stores all clock information in Hz
518 internally. For binary compatibility with older Linux
519 kernels (which expect the clocks passed in the
520 bd_info data to be in MHz) the environment variable
521 "clocks_in_mhz" can be defined so that U-Boot
522 converts clock data to MHZ before passing it to the
524 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
525 "clocks_in_mhz=1" is automatically included in the
528 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
530 When transferring memsize parameter to linux, some versions
531 expect it to be in bytes, others in MB.
532 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
536 New kernel versions are expecting firmware settings to be
537 passed using flattened device trees (based on open firmware
541 * New libfdt-based support
542 * Adds the "fdt" command
543 * The bootm command automatically updates the fdt
545 OF_CPU - The proper name of the cpus node (only required for
546 MPC512X and MPC5xxx based boards).
547 OF_SOC - The proper name of the soc node (only required for
548 MPC512X and MPC5xxx based boards).
549 OF_TBCLK - The timebase frequency.
550 OF_STDOUT_PATH - The path to the console device
552 boards with QUICC Engines require OF_QE to set UCC MAC
555 CONFIG_OF_BOARD_SETUP
557 Board code has addition modification that it wants to make
558 to the flat device tree before handing it off to the kernel
562 This define fills in the correct boot CPU in the boot
563 param header, the default value is zero if undefined.
567 U-Boot can detect if an IDE device is present or not.
568 If not, and this new config option is activated, U-Boot
569 removes the ATA node from the DTS before booting Linux,
570 so the Linux IDE driver does not probe the device and
571 crash. This is needed for buggy hardware (uc101) where
572 no pull down resistor is connected to the signal IDE5V_DD7.
574 CONFIG_MACH_TYPE [relevant for ARM only][mandatory]
576 This setting is mandatory for all boards that have only one
577 machine type and must be used to specify the machine type
578 number as it appears in the ARM machine registry
579 (see http://www.arm.linux.org.uk/developer/machines/).
580 Only boards that have multiple machine types supported
581 in a single configuration file and the machine type is
582 runtime discoverable, do not have to use this setting.
584 - vxWorks boot parameters:
586 bootvx constructs a valid bootline using the following
587 environments variables: bootfile, ipaddr, serverip, hostname.
588 It loads the vxWorks image pointed bootfile.
590 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name
591 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address
592 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server
593 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters
595 CONFIG_SYS_VXWORKS_ADD_PARAMS
597 Add it at the end of the bootline. E.g "u=username pw=secret"
599 Note: If a "bootargs" environment is defined, it will overwride
600 the defaults discussed just above.
602 - Cache Configuration:
603 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot
604 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot
605 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot
607 - Cache Configuration for ARM:
608 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache
610 CONFIG_SYS_PL310_BASE - Physical base address of PL310
611 controller register space
616 Define this if you want support for Amba PrimeCell PL010 UARTs.
620 Define this if you want support for Amba PrimeCell PL011 UARTs.
624 If you have Amba PrimeCell PL011 UARTs, set this variable to
625 the clock speed of the UARTs.
629 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
630 define this to a list of base addresses for each (supported)
631 port. See e.g. include/configs/versatile.h
633 CONFIG_PL011_SERIAL_RLCR
635 Some vendor versions of PL011 serial ports (e.g. ST-Ericsson U8500)
636 have separate receive and transmit line control registers. Set
637 this variable to initialize the extra register.
639 CONFIG_PL011_SERIAL_FLUSH_ON_INIT
641 On some platforms (e.g. U8500) U-Boot is loaded by a second stage
642 boot loader that has already initialized the UART. Define this
643 variable to flush the UART at init time.
647 Depending on board, define exactly one serial port
648 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
649 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
650 console by defining CONFIG_8xx_CONS_NONE
652 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
653 port routines must be defined elsewhere
654 (i.e. serial_init(), serial_getc(), ...)
657 Enables console device for a color framebuffer. Needs following
658 defines (cf. smiLynxEM, i8042)
659 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
661 VIDEO_HW_RECTFILL graphic chip supports
664 VIDEO_HW_BITBLT graphic chip supports
665 bit-blit (cf. smiLynxEM)
666 VIDEO_VISIBLE_COLS visible pixel columns
668 VIDEO_VISIBLE_ROWS visible pixel rows
669 VIDEO_PIXEL_SIZE bytes per pixel
670 VIDEO_DATA_FORMAT graphic data format
671 (0-5, cf. cfb_console.c)
672 VIDEO_FB_ADRS framebuffer address
673 VIDEO_KBD_INIT_FCT keyboard int fct
674 (i.e. i8042_kbd_init())
675 VIDEO_TSTC_FCT test char fct
677 VIDEO_GETC_FCT get char fct
679 CONFIG_CONSOLE_CURSOR cursor drawing on/off
680 (requires blink timer
682 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
683 CONFIG_CONSOLE_TIME display time/date info in
685 (requires CONFIG_CMD_DATE)
686 CONFIG_VIDEO_LOGO display Linux logo in
688 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
689 linux_logo.h for logo.
690 Requires CONFIG_VIDEO_LOGO
691 CONFIG_CONSOLE_EXTRA_INFO
692 additional board info beside
695 When CONFIG_CFB_CONSOLE_ANSI is defined, console will support
696 a limited number of ANSI escape sequences (cursor control,
697 erase functions and limited graphics rendition control).
699 When CONFIG_CFB_CONSOLE is defined, video console is
700 default i/o. Serial console can be forced with
701 environment 'console=serial'.
703 When CONFIG_SILENT_CONSOLE is defined, all console
704 messages (by U-Boot and Linux!) can be silenced with
705 the "silent" environment variable. See
706 doc/README.silent for more information.
708 CONFIG_SYS_CONSOLE_BG_COL: define the backgroundcolor, default
710 CONFIG_SYS_CONSOLE_FG_COL: define the foregroundcolor, default
714 CONFIG_BAUDRATE - in bps
715 Select one of the baudrates listed in
716 CONFIG_SYS_BAUDRATE_TABLE, see below.
717 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale
719 - Console Rx buffer length
720 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define
721 the maximum receive buffer length for the SMC.
722 This option is actual only for 82xx and 8xx possible.
723 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE
724 must be defined, to setup the maximum idle timeout for
727 - Pre-Console Buffer:
728 Prior to the console being initialised (i.e. serial UART
729 initialised etc) all console output is silently discarded.
730 Defining CONFIG_PRE_CONSOLE_BUFFER will cause U-Boot to
731 buffer any console messages prior to the console being
732 initialised to a buffer of size CONFIG_PRE_CON_BUF_SZ
733 bytes located at CONFIG_PRE_CON_BUF_ADDR. The buffer is
734 a circular buffer, so if more than CONFIG_PRE_CON_BUF_SZ
735 bytes are output before the console is initialised, the
736 earlier bytes are discarded.
738 'Sane' compilers will generate smaller code if
739 CONFIG_PRE_CON_BUF_SZ is a power of 2
741 - Safe printf() functions
742 Define CONFIG_SYS_VSNPRINTF to compile in safe versions of
743 the printf() functions. These are defined in
744 include/vsprintf.h and include snprintf(), vsnprintf() and
745 so on. Code size increase is approximately 300-500 bytes.
746 If this option is not given then these functions will
747 silently discard their buffer size argument - this means
748 you are not getting any overflow checking in this case.
750 - Boot Delay: CONFIG_BOOTDELAY - in seconds
751 Delay before automatically booting the default image;
752 set to -1 to disable autoboot.
753 set to -2 to autoboot with no delay and not check for abort
754 (even when CONFIG_ZERO_BOOTDELAY_CHECK is defined).
756 See doc/README.autoboot for these options that
757 work with CONFIG_BOOTDELAY. None are required.
758 CONFIG_BOOT_RETRY_TIME
759 CONFIG_BOOT_RETRY_MIN
760 CONFIG_AUTOBOOT_KEYED
761 CONFIG_AUTOBOOT_PROMPT
762 CONFIG_AUTOBOOT_DELAY_STR
763 CONFIG_AUTOBOOT_STOP_STR
764 CONFIG_AUTOBOOT_DELAY_STR2
765 CONFIG_AUTOBOOT_STOP_STR2
766 CONFIG_ZERO_BOOTDELAY_CHECK
767 CONFIG_RESET_TO_RETRY
771 Only needed when CONFIG_BOOTDELAY is enabled;
772 define a command string that is automatically executed
773 when no character is read on the console interface
774 within "Boot Delay" after reset.
777 This can be used to pass arguments to the bootm
778 command. The value of CONFIG_BOOTARGS goes into the
779 environment value "bootargs".
781 CONFIG_RAMBOOT and CONFIG_NFSBOOT
782 The value of these goes into the environment as
783 "ramboot" and "nfsboot" respectively, and can be used
784 as a convenience, when switching between booting from
790 When this option is #defined, the existence of the
791 environment variable "preboot" will be checked
792 immediately before starting the CONFIG_BOOTDELAY
793 countdown and/or running the auto-boot command resp.
794 entering interactive mode.
796 This feature is especially useful when "preboot" is
797 automatically generated or modified. For an example
798 see the LWMON board specific code: here "preboot" is
799 modified when the user holds down a certain
800 combination of keys on the (special) keyboard when
803 - Serial Download Echo Mode:
805 If defined to 1, all characters received during a
806 serial download (using the "loads" command) are
807 echoed back. This might be needed by some terminal
808 emulations (like "cu"), but may as well just take
809 time on others. This setting #define's the initial
810 value of the "loads_echo" environment variable.
812 - Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
814 Select one of the baudrates listed in
815 CONFIG_SYS_BAUDRATE_TABLE, see below.
818 Monitor commands can be included or excluded
819 from the build by using the #include files
820 <config_cmd_all.h> and #undef'ing unwanted
821 commands, or using <config_cmd_default.h>
822 and augmenting with additional #define's
825 The default command configuration includes all commands
826 except those marked below with a "*".
828 CONFIG_CMD_ASKENV * ask for env variable
829 CONFIG_CMD_BDI bdinfo
830 CONFIG_CMD_BEDBUG * Include BedBug Debugger
831 CONFIG_CMD_BMP * BMP support
832 CONFIG_CMD_BSP * Board specific commands
833 CONFIG_CMD_BOOTD bootd
834 CONFIG_CMD_CACHE * icache, dcache
835 CONFIG_CMD_CONSOLE coninfo
836 CONFIG_CMD_CRC32 * crc32
837 CONFIG_CMD_DATE * support for RTC, date/time...
838 CONFIG_CMD_DHCP * DHCP support
839 CONFIG_CMD_DIAG * Diagnostics
840 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands
841 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command
842 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd
843 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command
844 CONFIG_CMD_DTT * Digital Therm and Thermostat
845 CONFIG_CMD_ECHO echo arguments
846 CONFIG_CMD_EDITENV edit env variable
847 CONFIG_CMD_EEPROM * EEPROM read/write support
848 CONFIG_CMD_ELF * bootelf, bootvx
849 CONFIG_CMD_ENV_CALLBACK * display details about env callbacks
850 CONFIG_CMD_ENV_FLAGS * display details about env flags
851 CONFIG_CMD_ENV_EXISTS * check existence of env variable
852 CONFIG_CMD_EXPORTENV * export the environment
853 CONFIG_CMD_EXT2 * ext2 command support
854 CONFIG_CMD_EXT4 * ext4 command support
855 CONFIG_CMD_SAVEENV saveenv
856 CONFIG_CMD_FDC * Floppy Disk Support
857 CONFIG_CMD_FAT * FAT command support
858 CONFIG_CMD_FDOS * Dos diskette Support
859 CONFIG_CMD_FLASH flinfo, erase, protect
860 CONFIG_CMD_FPGA FPGA device initialization support
861 CONFIG_CMD_FUSE * Device fuse support
862 CONFIG_CMD_GETTIME * Get time since boot
863 CONFIG_CMD_GO * the 'go' command (exec code)
864 CONFIG_CMD_GREPENV * search environment
865 CONFIG_CMD_HASH * calculate hash / digest
866 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control
867 CONFIG_CMD_I2C * I2C serial bus support
868 CONFIG_CMD_IDE * IDE harddisk support
869 CONFIG_CMD_IMI iminfo
870 CONFIG_CMD_IMLS List all images found in NOR flash
871 CONFIG_CMD_IMLS_NAND * List all images found in NAND flash
872 CONFIG_CMD_IMMAP * IMMR dump support
873 CONFIG_CMD_IMPORTENV * import an environment
874 CONFIG_CMD_INI * import data from an ini file into the env
875 CONFIG_CMD_IRQ * irqinfo
876 CONFIG_CMD_ITEST Integer/string test of 2 values
877 CONFIG_CMD_JFFS2 * JFFS2 Support
878 CONFIG_CMD_KGDB * kgdb
879 CONFIG_CMD_LDRINFO * ldrinfo (display Blackfin loader)
880 CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration
882 CONFIG_CMD_LOADB loadb
883 CONFIG_CMD_LOADS loads
884 CONFIG_CMD_MD5SUM * print md5 message digest
885 (requires CONFIG_CMD_MEMORY and CONFIG_MD5)
886 CONFIG_CMD_MEMINFO * Display detailed memory information
887 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
889 CONFIG_CMD_MEMTEST * mtest
890 CONFIG_CMD_MISC Misc functions like sleep etc
891 CONFIG_CMD_MMC * MMC memory mapped support
892 CONFIG_CMD_MII * MII utility commands
893 CONFIG_CMD_MTDPARTS * MTD partition support
894 CONFIG_CMD_NAND * NAND support
895 CONFIG_CMD_NET bootp, tftpboot, rarpboot
896 CONFIG_CMD_NFS NFS support
897 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands
898 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command
899 CONFIG_CMD_PCI * pciinfo
900 CONFIG_CMD_PCMCIA * PCMCIA support
901 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network
903 CONFIG_CMD_PORTIO * Port I/O
904 CONFIG_CMD_READ * Read raw data from partition
905 CONFIG_CMD_REGINFO * Register dump
906 CONFIG_CMD_RUN run command in env variable
907 CONFIG_CMD_SANDBOX * sb command to access sandbox features
908 CONFIG_CMD_SAVES * save S record dump
909 CONFIG_CMD_SCSI * SCSI Support
910 CONFIG_CMD_SDRAM * print SDRAM configuration information
911 (requires CONFIG_CMD_I2C)
912 CONFIG_CMD_SETGETDCR Support for DCR Register access
914 CONFIG_CMD_SF * Read/write/erase SPI NOR flash
915 CONFIG_CMD_SHA1SUM * print sha1 memory digest
916 (requires CONFIG_CMD_MEMORY)
917 CONFIG_CMD_SOFTSWITCH * Soft switch setting command for BF60x
918 CONFIG_CMD_SOURCE "source" command Support
919 CONFIG_CMD_SPI * SPI serial bus support
920 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode
921 CONFIG_CMD_TFTPPUT * TFTP put command (upload)
922 CONFIG_CMD_TIME * run command and report execution time (ARM specific)
923 CONFIG_CMD_TIMER * access to the system tick timer
924 CONFIG_CMD_USB * USB support
925 CONFIG_CMD_CDP * Cisco Discover Protocol support
926 CONFIG_CMD_MFSL * Microblaze FSL support
927 CONFIG_CMD_XIMG Load part of Multi Image
930 EXAMPLE: If you want all functions except of network
931 support you can write:
933 #include "config_cmd_all.h"
934 #undef CONFIG_CMD_NET
937 fdt (flattened device tree) command: CONFIG_OF_LIBFDT
939 Note: Don't enable the "icache" and "dcache" commands
940 (configuration option CONFIG_CMD_CACHE) unless you know
941 what you (and your U-Boot users) are doing. Data
942 cache cannot be enabled on systems like the 8xx or
943 8260 (where accesses to the IMMR region must be
944 uncached), and it cannot be disabled on all other
945 systems where we (mis-) use the data cache to hold an
946 initial stack and some data.
949 XXX - this list needs to get updated!
951 - Regular expression support:
953 If this variable is defined, U-Boot is linked against
954 the SLRE (Super Light Regular Expression) library,
955 which adds regex support to some commands, as for
956 example "env grep" and "setexpr".
960 If this variable is defined, U-Boot will use a device tree
961 to configure its devices, instead of relying on statically
962 compiled #defines in the board file. This option is
963 experimental and only available on a few boards. The device
964 tree is available in the global data as gd->fdt_blob.
966 U-Boot needs to get its device tree from somewhere. This can
967 be done using one of the two options below:
970 If this variable is defined, U-Boot will embed a device tree
971 binary in its image. This device tree file should be in the
972 board directory and called <soc>-<board>.dts. The binary file
973 is then picked up in board_init_f() and made available through
974 the global data structure as gd->blob.
977 If this variable is defined, U-Boot will build a device tree
978 binary. It will be called u-boot.dtb. Architecture-specific
979 code will locate it at run-time. Generally this works by:
981 cat u-boot.bin u-boot.dtb >image.bin
983 and in fact, U-Boot does this for you, creating a file called
984 u-boot-dtb.bin which is useful in the common case. You can
985 still use the individual files if you need something more
990 If this variable is defined, it enables watchdog
991 support for the SoC. There must be support in the SoC
992 specific code for a watchdog. For the 8xx and 8260
993 CPUs, the SIU Watchdog feature is enabled in the SYPCR
994 register. When supported for a specific SoC is
995 available, then no further board specific code should
999 When using a watchdog circuitry external to the used
1000 SoC, then define this variable and provide board
1001 specific code for the "hw_watchdog_reset" function.
1004 CONFIG_VERSION_VARIABLE
1005 If this variable is defined, an environment variable
1006 named "ver" is created by U-Boot showing the U-Boot
1007 version as printed by the "version" command.
1008 Any change to this variable will be reverted at the
1013 When CONFIG_CMD_DATE is selected, the type of the RTC
1014 has to be selected, too. Define exactly one of the
1017 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
1018 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
1019 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC
1020 CONFIG_RTC_MC146818 - use MC146818 RTC
1021 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
1022 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
1023 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
1024 CONFIG_RTC_DS164x - use Dallas DS164x RTC
1025 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
1026 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
1027 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
1028 CONFIG_SYS_RV3029_TCR - enable trickle charger on
1031 Note that if the RTC uses I2C, then the I2C interface
1032 must also be configured. See I2C Support, below.
1035 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
1036 CONFIG_PCA953X_INFO - enable pca953x info command
1038 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
1039 chip-ngpio pairs that tell the PCA953X driver the number of
1040 pins supported by a particular chip.
1042 Note that if the GPIO device uses I2C, then the I2C interface
1043 must also be configured. See I2C Support, below.
1045 - Timestamp Support:
1047 When CONFIG_TIMESTAMP is selected, the timestamp
1048 (date and time) of an image is printed by image
1049 commands like bootm or iminfo. This option is
1050 automatically enabled when you select CONFIG_CMD_DATE .
1052 - Partition Labels (disklabels) Supported:
1053 Zero or more of the following:
1054 CONFIG_MAC_PARTITION Apple's MacOS partition table.
1055 CONFIG_DOS_PARTITION MS Dos partition table, traditional on the
1056 Intel architecture, USB sticks, etc.
1057 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc.
1058 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the
1059 bootloader. Note 2TB partition limit; see
1061 CONFIG_MTD_PARTITIONS Memory Technology Device partition table.
1063 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or
1064 CONFIG_CMD_SCSI) you must configure support for at
1065 least one non-MTD partition type as well.
1068 CONFIG_IDE_RESET_ROUTINE - this is defined in several
1069 board configurations files but used nowhere!
1071 CONFIG_IDE_RESET - is this is defined, IDE Reset will
1072 be performed by calling the function
1073 ide_set_reset(int reset)
1074 which has to be defined in a board specific file
1079 Set this to enable ATAPI support.
1084 Set this to enable support for disks larger than 137GB
1085 Also look at CONFIG_SYS_64BIT_LBA.
1086 Whithout these , LBA48 support uses 32bit variables and will 'only'
1087 support disks up to 2.1TB.
1089 CONFIG_SYS_64BIT_LBA:
1090 When enabled, makes the IDE subsystem use 64bit sector addresses.
1094 At the moment only there is only support for the
1095 SYM53C8XX SCSI controller; define
1096 CONFIG_SCSI_SYM53C8XX to enable it.
1098 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
1099 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
1100 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
1101 maximum numbers of LUNs, SCSI ID's and target
1103 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
1105 The environment variable 'scsidevs' is set to the number of
1106 SCSI devices found during the last scan.
1108 - NETWORK Support (PCI):
1110 Support for Intel 8254x/8257x gigabit chips.
1113 Utility code for direct access to the SPI bus on Intel 8257x.
1114 This does not do anything useful unless you set at least one
1115 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC.
1117 CONFIG_E1000_SPI_GENERIC
1118 Allow generic access to the SPI bus on the Intel 8257x, for
1119 example with the "sspi" command.
1122 Management command for E1000 devices. When used on devices
1123 with SPI support you can reprogram the EEPROM from U-Boot.
1125 CONFIG_E1000_FALLBACK_MAC
1126 default MAC for empty EEPROM after production.
1129 Support for Intel 82557/82559/82559ER chips.
1130 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
1131 write routine for first time initialisation.
1134 Support for Digital 2114x chips.
1135 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
1136 modem chip initialisation (KS8761/QS6611).
1139 Support for National dp83815 chips.
1142 Support for National dp8382[01] gigabit chips.
1144 - NETWORK Support (other):
1146 CONFIG_DRIVER_AT91EMAC
1147 Support for AT91RM9200 EMAC.
1150 Define this to use reduced MII inteface
1152 CONFIG_DRIVER_AT91EMAC_QUIET
1153 If this defined, the driver is quiet.
1154 The driver doen't show link status messages.
1156 CONFIG_CALXEDA_XGMAC
1157 Support for the Calxeda XGMAC device
1160 Support for SMSC's LAN91C96 chips.
1162 CONFIG_LAN91C96_BASE
1163 Define this to hold the physical address
1164 of the LAN91C96's I/O space
1166 CONFIG_LAN91C96_USE_32_BIT
1167 Define this to enable 32 bit addressing
1170 Support for SMSC's LAN91C111 chip
1172 CONFIG_SMC91111_BASE
1173 Define this to hold the physical address
1174 of the device (I/O space)
1176 CONFIG_SMC_USE_32_BIT
1177 Define this if data bus is 32 bits
1179 CONFIG_SMC_USE_IOFUNCS
1180 Define this to use i/o functions instead of macros
1181 (some hardware wont work with macros)
1183 CONFIG_DRIVER_TI_EMAC
1184 Support for davinci emac
1186 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT
1187 Define this if you have more then 3 PHYs.
1190 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
1192 CONFIG_FTGMAC100_EGIGA
1193 Define this to use GE link update with gigabit PHY.
1194 Define this if FTGMAC100 is connected to gigabit PHY.
1195 If your system has 10/100 PHY only, it might not occur
1196 wrong behavior. Because PHY usually return timeout or
1197 useless data when polling gigabit status and gigabit
1198 control registers. This behavior won't affect the
1199 correctnessof 10/100 link speed update.
1202 Support for SMSC's LAN911x and LAN921x chips
1205 Define this to hold the physical address
1206 of the device (I/O space)
1208 CONFIG_SMC911X_32_BIT
1209 Define this if data bus is 32 bits
1211 CONFIG_SMC911X_16_BIT
1212 Define this if data bus is 16 bits. If your processor
1213 automatically converts one 32 bit word to two 16 bit
1214 words you may also try CONFIG_SMC911X_32_BIT.
1217 Support for Renesas on-chip Ethernet controller
1219 CONFIG_SH_ETHER_USE_PORT
1220 Define the number of ports to be used
1222 CONFIG_SH_ETHER_PHY_ADDR
1223 Define the ETH PHY's address
1225 CONFIG_SH_ETHER_CACHE_WRITEBACK
1226 If this option is set, the driver enables cache flush.
1230 Support TPM devices.
1233 Support for i2c bus TPM devices. Only one device
1234 per system is supported at this time.
1236 CONFIG_TPM_TIS_I2C_BUS_NUMBER
1237 Define the the i2c bus number for the TPM device
1239 CONFIG_TPM_TIS_I2C_SLAVE_ADDRESS
1240 Define the TPM's address on the i2c bus
1242 CONFIG_TPM_TIS_I2C_BURST_LIMITATION
1243 Define the burst count bytes upper limit
1245 CONFIG_TPM_ATMEL_TWI
1246 Support for Atmel TWI TPM device. Requires I2C support.
1249 Support for generic parallel port TPM devices. Only one device
1250 per system is supported at this time.
1252 CONFIG_TPM_TIS_BASE_ADDRESS
1253 Base address where the generic TPM device is mapped
1254 to. Contemporary x86 systems usually map it at
1258 Add tpm monitor functions.
1259 Requires CONFIG_TPM. If CONFIG_TPM_AUTH_SESSIONS is set, also
1260 provides monitor access to authorized functions.
1263 Define this to enable the TPM support library which provides
1264 functional interfaces to some TPM commands.
1265 Requires support for a TPM device.
1267 CONFIG_TPM_AUTH_SESSIONS
1268 Define this to enable authorized functions in the TPM library.
1269 Requires CONFIG_TPM and CONFIG_SHA1.
1272 At the moment only the UHCI host controller is
1273 supported (PIP405, MIP405, MPC5200); define
1274 CONFIG_USB_UHCI to enable it.
1275 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
1276 and define CONFIG_USB_STORAGE to enable the USB
1279 Supported are USB Keyboards and USB Floppy drives
1281 MPC5200 USB requires additional defines:
1283 for 528 MHz Clock: 0x0001bbbb
1287 for differential drivers: 0x00001000
1288 for single ended drivers: 0x00005000
1289 for differential drivers on PSC3: 0x00000100
1290 for single ended drivers on PSC3: 0x00004100
1291 CONFIG_SYS_USB_EVENT_POLL
1292 May be defined to allow interrupt polling
1293 instead of using asynchronous interrupts
1295 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the
1296 txfilltuning field in the EHCI controller on reset.
1298 CONFIG_USB_HUB_MIN_POWER_ON_DELAY defines the minimum
1299 interval for usb hub power-on delay.(minimum 100msec)
1302 Define the below if you wish to use the USB console.
1303 Once firmware is rebuilt from a serial console issue the
1304 command "setenv stdin usbtty; setenv stdout usbtty" and
1305 attach your USB cable. The Unix command "dmesg" should print
1306 it has found a new device. The environment variable usbtty
1307 can be set to gserial or cdc_acm to enable your device to
1308 appear to a USB host as a Linux gserial device or a
1309 Common Device Class Abstract Control Model serial device.
1310 If you select usbtty = gserial you should be able to enumerate
1312 # modprobe usbserial vendor=0xVendorID product=0xProductID
1313 else if using cdc_acm, simply setting the environment
1314 variable usbtty to be cdc_acm should suffice. The following
1315 might be defined in YourBoardName.h
1318 Define this to build a UDC device
1321 Define this to have a tty type of device available to
1322 talk to the UDC device
1325 Define this to enable the high speed support for usb
1326 device and usbtty. If this feature is enabled, a routine
1327 int is_usbd_high_speed(void)
1328 also needs to be defined by the driver to dynamically poll
1329 whether the enumeration has succeded at high speed or full
1332 CONFIG_SYS_CONSOLE_IS_IN_ENV
1333 Define this if you want stdin, stdout &/or stderr to
1337 CONFIG_SYS_USB_EXTC_CLK 0xBLAH
1338 Derive USB clock from external clock "blah"
1339 - CONFIG_SYS_USB_EXTC_CLK 0x02
1341 CONFIG_SYS_USB_BRG_CLK 0xBLAH
1342 Derive USB clock from brgclk
1343 - CONFIG_SYS_USB_BRG_CLK 0x04
1345 If you have a USB-IF assigned VendorID then you may wish to
1346 define your own vendor specific values either in BoardName.h
1347 or directly in usbd_vendor_info.h. If you don't define
1348 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
1349 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
1350 should pretend to be a Linux device to it's target host.
1352 CONFIG_USBD_MANUFACTURER
1353 Define this string as the name of your company for
1354 - CONFIG_USBD_MANUFACTURER "my company"
1356 CONFIG_USBD_PRODUCT_NAME
1357 Define this string as the name of your product
1358 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
1360 CONFIG_USBD_VENDORID
1361 Define this as your assigned Vendor ID from the USB
1362 Implementors Forum. This *must* be a genuine Vendor ID
1363 to avoid polluting the USB namespace.
1364 - CONFIG_USBD_VENDORID 0xFFFF
1366 CONFIG_USBD_PRODUCTID
1367 Define this as the unique Product ID
1369 - CONFIG_USBD_PRODUCTID 0xFFFF
1371 - ULPI Layer Support:
1372 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via
1373 the generic ULPI layer. The generic layer accesses the ULPI PHY
1374 via the platform viewport, so you need both the genric layer and
1375 the viewport enabled. Currently only Chipidea/ARC based
1376 viewport is supported.
1377 To enable the ULPI layer support, define CONFIG_USB_ULPI and
1378 CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
1379 If your ULPI phy needs a different reference clock than the
1380 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to
1381 the appropriate value in Hz.
1384 The MMC controller on the Intel PXA is supported. To
1385 enable this define CONFIG_MMC. The MMC can be
1386 accessed from the boot prompt by mapping the device
1387 to physical memory similar to flash. Command line is
1388 enabled with CONFIG_CMD_MMC. The MMC driver also works with
1389 the FAT fs. This is enabled with CONFIG_CMD_FAT.
1392 Support for Renesas on-chip MMCIF controller
1394 CONFIG_SH_MMCIF_ADDR
1395 Define the base address of MMCIF registers
1398 Define the clock frequency for MMCIF
1400 - USB Device Firmware Update (DFU) class support:
1402 This enables the USB portion of the DFU USB class
1405 This enables the command "dfu" which is used to have
1406 U-Boot create a DFU class device via USB. This command
1407 requires that the "dfu_alt_info" environment variable be
1408 set and define the alt settings to expose to the host.
1411 This enables support for exposing (e)MMC devices via DFU.
1414 This enables support for exposing NAND devices via DFU.
1417 This enables support for exposing RAM via DFU.
1418 Note: DFU spec refer to non-volatile memory usage, but
1419 allow usages beyond the scope of spec - here RAM usage,
1420 one that would help mostly the developer.
1422 CONFIG_SYS_DFU_DATA_BUF_SIZE
1423 Dfu transfer uses a buffer before writing data to the
1424 raw storage device. Make the size (in bytes) of this buffer
1425 configurable. The size of this buffer is also configurable
1426 through the "dfu_bufsiz" environment variable.
1428 CONFIG_SYS_DFU_MAX_FILE_SIZE
1429 When updating files rather than the raw storage device,
1430 we use a static buffer to copy the file into and then write
1431 the buffer once we've been given the whole file. Define
1432 this to the maximum filesize (in bytes) for the buffer.
1433 Default is 4 MiB if undefined.
1435 - Journaling Flash filesystem support:
1436 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
1437 CONFIG_JFFS2_NAND_DEV
1438 Define these for a default partition on a NAND device
1440 CONFIG_SYS_JFFS2_FIRST_SECTOR,
1441 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
1442 Define these for a default partition on a NOR device
1444 CONFIG_SYS_JFFS_CUSTOM_PART
1445 Define this to create an own partition. You have to provide a
1446 function struct part_info* jffs2_part_info(int part_num)
1448 If you define only one JFFS2 partition you may also want to
1449 #define CONFIG_SYS_JFFS_SINGLE_PART 1
1450 to disable the command chpart. This is the default when you
1451 have not defined a custom partition
1453 - FAT(File Allocation Table) filesystem write function support:
1456 Define this to enable support for saving memory data as a
1457 file in FAT formatted partition.
1459 This will also enable the command "fatwrite" enabling the
1460 user to write files to FAT.
1462 CBFS (Coreboot Filesystem) support
1465 Define this to enable support for reading from a Coreboot
1466 filesystem. Available commands are cbfsinit, cbfsinfo, cbfsls
1472 Define this to enable standard (PC-Style) keyboard
1476 Standard PC keyboard driver with US (is default) and
1477 GERMAN key layout (switch via environment 'keymap=de') support.
1478 Export function i8042_kbd_init, i8042_tstc and i8042_getc
1479 for cfb_console. Supports cursor blinking.
1482 Enables a Chrome OS keyboard using the CROS_EC interface.
1483 This uses CROS_EC to communicate with a second microcontroller
1484 which provides key scans on request.
1489 Define this to enable video support (for output to
1492 CONFIG_VIDEO_CT69000
1494 Enable Chips & Technologies 69000 Video chip
1496 CONFIG_VIDEO_SMI_LYNXEM
1497 Enable Silicon Motion SMI 712/710/810 Video chip. The
1498 video output is selected via environment 'videoout'
1499 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
1502 For the CT69000 and SMI_LYNXEM drivers, videomode is
1503 selected via environment 'videomode'. Two different ways
1505 - "videomode=num" 'num' is a standard LiLo mode numbers.
1506 Following standard modes are supported (* is default):
1508 Colors 640x480 800x600 1024x768 1152x864 1280x1024
1509 -------------+---------------------------------------------
1510 8 bits | 0x301* 0x303 0x305 0x161 0x307
1511 15 bits | 0x310 0x313 0x316 0x162 0x319
1512 16 bits | 0x311 0x314 0x317 0x163 0x31A
1513 24 bits | 0x312 0x315 0x318 ? 0x31B
1514 -------------+---------------------------------------------
1515 (i.e. setenv videomode 317; saveenv; reset;)
1517 - "videomode=bootargs" all the video parameters are parsed
1518 from the bootargs. (See drivers/video/videomodes.c)
1521 CONFIG_VIDEO_SED13806
1522 Enable Epson SED13806 driver. This driver supports 8bpp
1523 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
1524 or CONFIG_VIDEO_SED13806_16BPP
1527 Enable the Freescale DIU video driver. Reference boards for
1528 SOCs that have a DIU should define this macro to enable DIU
1529 support, and should also define these other macros:
1535 CONFIG_VIDEO_SW_CURSOR
1536 CONFIG_VGA_AS_SINGLE_DEVICE
1538 CONFIG_VIDEO_BMP_LOGO
1540 The DIU driver will look for the 'video-mode' environment
1541 variable, and if defined, enable the DIU as a console during
1542 boot. See the documentation file README.video for a
1543 description of this variable.
1547 Enable the VGA video / BIOS for x86. The alternative if you
1548 are using coreboot is to use the coreboot frame buffer
1555 Define this to enable a custom keyboard support.
1556 This simply calls drv_keyboard_init() which must be
1557 defined in your board-specific files.
1558 The only board using this so far is RBC823.
1560 - LCD Support: CONFIG_LCD
1562 Define this to enable LCD support (for output to LCD
1563 display); also select one of the supported displays
1564 by defining one of these:
1568 HITACHI TX09D70VM1CCA, 3.5", 240x320.
1570 CONFIG_NEC_NL6448AC33:
1572 NEC NL6448AC33-18. Active, color, single scan.
1574 CONFIG_NEC_NL6448BC20
1576 NEC NL6448BC20-08. 6.5", 640x480.
1577 Active, color, single scan.
1579 CONFIG_NEC_NL6448BC33_54
1581 NEC NL6448BC33-54. 10.4", 640x480.
1582 Active, color, single scan.
1586 Sharp 320x240. Active, color, single scan.
1587 It isn't 16x9, and I am not sure what it is.
1589 CONFIG_SHARP_LQ64D341
1591 Sharp LQ64D341 display, 640x480.
1592 Active, color, single scan.
1596 HLD1045 display, 640x480.
1597 Active, color, single scan.
1601 Optrex CBL50840-2 NF-FW 99 22 M5
1603 Hitachi LMG6912RPFC-00T
1607 320x240. Black & white.
1609 Normally display is black on white background; define
1610 CONFIG_SYS_WHITE_ON_BLACK to get it inverted.
1612 CONFIG_LCD_ALIGNMENT
1614 Normally the LCD is page-aligned (tyically 4KB). If this is
1615 defined then the LCD will be aligned to this value instead.
1616 For ARM it is sometimes useful to use MMU_SECTION_SIZE
1617 here, since it is cheaper to change data cache settings on
1618 a per-section basis.
1620 CONFIG_CONSOLE_SCROLL_LINES
1622 When the console need to be scrolled, this is the number of
1623 lines to scroll by. It defaults to 1. Increasing this makes
1624 the console jump but can help speed up operation when scrolling
1629 Support drawing of RLE8-compressed bitmaps on the LCD.
1633 Enables an 'i2c edid' command which can read EDID
1634 information over I2C from an attached LCD display.
1636 - Splash Screen Support: CONFIG_SPLASH_SCREEN
1638 If this option is set, the environment is checked for
1639 a variable "splashimage". If found, the usual display
1640 of logo, copyright and system information on the LCD
1641 is suppressed and the BMP image at the address
1642 specified in "splashimage" is loaded instead. The
1643 console is redirected to the "nulldev", too. This
1644 allows for a "silent" boot where a splash screen is
1645 loaded very quickly after power-on.
1647 CONFIG_SPLASHIMAGE_GUARD
1649 If this option is set, then U-Boot will prevent the environment
1650 variable "splashimage" from being set to a problematic address
1651 (see README.displaying-bmps and README.arm-unaligned-accesses).
1652 This option is useful for targets where, due to alignment
1653 restrictions, an improperly aligned BMP image will cause a data
1654 abort. If you think you will not have problems with unaligned
1655 accesses (for example because your toolchain prevents them)
1656 there is no need to set this option.
1658 CONFIG_SPLASH_SCREEN_ALIGN
1660 If this option is set the splash image can be freely positioned
1661 on the screen. Environment variable "splashpos" specifies the
1662 position as "x,y". If a positive number is given it is used as
1663 number of pixel from left/top. If a negative number is given it
1664 is used as number of pixel from right/bottom. You can also
1665 specify 'm' for centering the image.
1668 setenv splashpos m,m
1669 => image at center of screen
1671 setenv splashpos 30,20
1672 => image at x = 30 and y = 20
1674 setenv splashpos -10,m
1675 => vertically centered image
1676 at x = dspWidth - bmpWidth - 9
1678 - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
1680 If this option is set, additionally to standard BMP
1681 images, gzipped BMP images can be displayed via the
1682 splashscreen support or the bmp command.
1684 - Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
1686 If this option is set, 8-bit RLE compressed BMP images
1687 can be displayed via the splashscreen support or the
1690 - Do compresssing for memory range:
1693 If this option is set, it would use zlib deflate method
1694 to compress the specified memory at its best effort.
1696 - Compression support:
1699 Enabled by default to support gzip compressed images.
1703 If this option is set, support for bzip2 compressed
1704 images is included. If not, only uncompressed and gzip
1705 compressed images are supported.
1707 NOTE: the bzip2 algorithm requires a lot of RAM, so
1708 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
1713 If this option is set, support for lzma compressed
1716 Note: The LZMA algorithm adds between 2 and 4KB of code and it
1717 requires an amount of dynamic memory that is given by the
1720 (1846 + 768 << (lc + lp)) * sizeof(uint16)
1722 Where lc and lp stand for, respectively, Literal context bits
1723 and Literal pos bits.
1725 This value is upper-bounded by 14MB in the worst case. Anyway,
1726 for a ~4MB large kernel image, we have lc=3 and lp=0 for a
1727 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is
1728 a very small buffer.
1730 Use the lzmainfo tool to determinate the lc and lp values and
1731 then calculate the amount of needed dynamic memory (ensuring
1732 the appropriate CONFIG_SYS_MALLOC_LEN value).
1736 If this option is set, support for LZO compressed images
1742 The address of PHY on MII bus.
1744 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1746 The clock frequency of the MII bus
1750 If this option is set, support for speed/duplex
1751 detection of gigabit PHY is included.
1753 CONFIG_PHY_RESET_DELAY
1755 Some PHY like Intel LXT971A need extra delay after
1756 reset before any MII register access is possible.
1757 For such PHY, set this option to the usec delay
1758 required. (minimum 300usec for LXT971A)
1760 CONFIG_PHY_CMD_DELAY (ppc4xx)
1762 Some PHY like Intel LXT971A need extra delay after
1763 command issued before MII status register can be read
1773 Define a default value for Ethernet address to use
1774 for the respective Ethernet interface, in case this
1775 is not determined automatically.
1780 Define a default value for the IP address to use for
1781 the default Ethernet interface, in case this is not
1782 determined through e.g. bootp.
1783 (Environment variable "ipaddr")
1785 - Server IP address:
1788 Defines a default value for the IP address of a TFTP
1789 server to contact when using the "tftboot" command.
1790 (Environment variable "serverip")
1792 CONFIG_KEEP_SERVERADDR
1794 Keeps the server's MAC address, in the env 'serveraddr'
1795 for passing to bootargs (like Linux's netconsole option)
1797 - Gateway IP address:
1800 Defines a default value for the IP address of the
1801 default router where packets to other networks are
1803 (Environment variable "gatewayip")
1808 Defines a default value for the subnet mask (or
1809 routing prefix) which is used to determine if an IP
1810 address belongs to the local subnet or needs to be
1811 forwarded through a router.
1812 (Environment variable "netmask")
1814 - Multicast TFTP Mode:
1817 Defines whether you want to support multicast TFTP as per
1818 rfc-2090; for example to work with atftp. Lets lots of targets
1819 tftp down the same boot image concurrently. Note: the Ethernet
1820 driver in use must provide a function: mcast() to join/leave a
1823 - BOOTP Recovery Mode:
1824 CONFIG_BOOTP_RANDOM_DELAY
1826 If you have many targets in a network that try to
1827 boot using BOOTP, you may want to avoid that all
1828 systems send out BOOTP requests at precisely the same
1829 moment (which would happen for instance at recovery
1830 from a power failure, when all systems will try to
1831 boot, thus flooding the BOOTP server. Defining
1832 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1833 inserted before sending out BOOTP requests. The
1834 following delays are inserted then:
1836 1st BOOTP request: delay 0 ... 1 sec
1837 2nd BOOTP request: delay 0 ... 2 sec
1838 3rd BOOTP request: delay 0 ... 4 sec
1840 BOOTP requests: delay 0 ... 8 sec
1842 - DHCP Advanced Options:
1843 You can fine tune the DHCP functionality by defining
1844 CONFIG_BOOTP_* symbols:
1846 CONFIG_BOOTP_SUBNETMASK
1847 CONFIG_BOOTP_GATEWAY
1848 CONFIG_BOOTP_HOSTNAME
1849 CONFIG_BOOTP_NISDOMAIN
1850 CONFIG_BOOTP_BOOTPATH
1851 CONFIG_BOOTP_BOOTFILESIZE
1854 CONFIG_BOOTP_SEND_HOSTNAME
1855 CONFIG_BOOTP_NTPSERVER
1856 CONFIG_BOOTP_TIMEOFFSET
1857 CONFIG_BOOTP_VENDOREX
1858 CONFIG_BOOTP_MAY_FAIL
1860 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
1861 environment variable, not the BOOTP server.
1863 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found
1864 after the configured retry count, the call will fail
1865 instead of starting over. This can be used to fail over
1866 to Link-local IP address configuration if the DHCP server
1869 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
1870 serverip from a DHCP server, it is possible that more
1871 than one DNS serverip is offered to the client.
1872 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1873 serverip will be stored in the additional environment
1874 variable "dnsip2". The first DNS serverip is always
1875 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
1878 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1879 to do a dynamic update of a DNS server. To do this, they
1880 need the hostname of the DHCP requester.
1881 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
1882 of the "hostname" environment variable is passed as
1883 option 12 to the DHCP server.
1885 CONFIG_BOOTP_DHCP_REQUEST_DELAY
1887 A 32bit value in microseconds for a delay between
1888 receiving a "DHCP Offer" and sending the "DHCP Request".
1889 This fixes a problem with certain DHCP servers that don't
1890 respond 100% of the time to a "DHCP request". E.g. On an
1891 AT91RM9200 processor running at 180MHz, this delay needed
1892 to be *at least* 15,000 usec before a Windows Server 2003
1893 DHCP server would reply 100% of the time. I recommend at
1894 least 50,000 usec to be safe. The alternative is to hope
1895 that one of the retries will be successful but note that
1896 the DHCP timeout and retry process takes a longer than
1899 - Link-local IP address negotiation:
1900 Negotiate with other link-local clients on the local network
1901 for an address that doesn't require explicit configuration.
1902 This is especially useful if a DHCP server cannot be guaranteed
1903 to exist in all environments that the device must operate.
1905 See doc/README.link-local for more information.
1908 CONFIG_CDP_DEVICE_ID
1910 The device id used in CDP trigger frames.
1912 CONFIG_CDP_DEVICE_ID_PREFIX
1914 A two character string which is prefixed to the MAC address
1919 A printf format string which contains the ascii name of
1920 the port. Normally is set to "eth%d" which sets
1921 eth0 for the first Ethernet, eth1 for the second etc.
1923 CONFIG_CDP_CAPABILITIES
1925 A 32bit integer which indicates the device capabilities;
1926 0x00000010 for a normal host which does not forwards.
1930 An ascii string containing the version of the software.
1934 An ascii string containing the name of the platform.
1938 A 32bit integer sent on the trigger.
1940 CONFIG_CDP_POWER_CONSUMPTION
1942 A 16bit integer containing the power consumption of the
1943 device in .1 of milliwatts.
1945 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1947 A byte containing the id of the VLAN.
1949 - Status LED: CONFIG_STATUS_LED
1951 Several configurations allow to display the current
1952 status using a LED. For instance, the LED will blink
1953 fast while running U-Boot code, stop blinking as
1954 soon as a reply to a BOOTP request was received, and
1955 start blinking slow once the Linux kernel is running
1956 (supported by a status LED driver in the Linux
1957 kernel). Defining CONFIG_STATUS_LED enables this
1960 - CAN Support: CONFIG_CAN_DRIVER
1962 Defining CONFIG_CAN_DRIVER enables CAN driver support
1963 on those systems that support this (optional)
1964 feature, like the TQM8xxL modules.
1966 - I2C Support: CONFIG_SYS_I2C
1968 This enable the NEW i2c subsystem, and will allow you to use
1969 i2c commands at the u-boot command line (as long as you set
1970 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c
1971 based realtime clock chips or other i2c devices. See
1972 common/cmd_i2c.c for a description of the command line
1975 ported i2c driver to the new framework:
1976 - drivers/i2c/soft_i2c.c:
1977 - activate first bus with CONFIG_SYS_I2C_SOFT define
1978 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE
1979 for defining speed and slave address
1980 - activate second bus with I2C_SOFT_DECLARATIONS2 define
1981 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2
1982 for defining speed and slave address
1983 - activate third bus with I2C_SOFT_DECLARATIONS3 define
1984 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3
1985 for defining speed and slave address
1986 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define
1987 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4
1988 for defining speed and slave address
1990 - drivers/i2c/fsl_i2c.c:
1991 - activate i2c driver with CONFIG_SYS_I2C_FSL
1992 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register
1993 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and
1994 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first
1996 - If your board supports a second fsl i2c bus, define
1997 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset
1998 CONFIG_SYS_FSL_I2C2_SPEED for the speed and
1999 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the
2002 - drivers/i2c/tegra_i2c.c:
2003 - activate this driver with CONFIG_SYS_I2C_TEGRA
2004 - This driver adds 4 i2c buses with a fix speed from
2005 100000 and the slave addr 0!
2007 - drivers/i2c/ppc4xx_i2c.c
2008 - activate this driver with CONFIG_SYS_I2C_PPC4XX
2009 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0
2010 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1
2012 - drivers/i2c/i2c_mxc.c
2013 - activate this driver with CONFIG_SYS_I2C_MXC
2014 - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED
2015 - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE
2016 - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED
2017 - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE
2018 - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED
2019 - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE
2020 If thoses defines are not set, default value is 100000
2021 for speed, and 0 for slave.
2023 - drivers/i2c/rcar_i2c.c:
2024 - activate this driver with CONFIG_SYS_I2C_RCAR
2025 - This driver adds 4 i2c buses
2027 - CONFIG_SYS_RCAR_I2C0_BASE for setting the register channel 0
2028 - CONFIG_SYS_RCAR_I2C0_SPEED for for the speed channel 0
2029 - CONFIG_SYS_RCAR_I2C1_BASE for setting the register channel 1
2030 - CONFIG_SYS_RCAR_I2C1_SPEED for for the speed channel 1
2031 - CONFIG_SYS_RCAR_I2C2_BASE for setting the register channel 2
2032 - CONFIG_SYS_RCAR_I2C2_SPEED for for the speed channel 2
2033 - CONFIG_SYS_RCAR_I2C3_BASE for setting the register channel 3
2034 - CONFIG_SYS_RCAR_I2C3_SPEED for for the speed channel 3
2035 - CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS for number of i2c buses
2039 CONFIG_SYS_NUM_I2C_BUSES
2040 Hold the number of i2c busses you want to use. If you
2041 don't use/have i2c muxes on your i2c bus, this
2042 is equal to CONFIG_SYS_NUM_I2C_ADAPTERS, and you can
2045 CONFIG_SYS_I2C_DIRECT_BUS
2046 define this, if you don't use i2c muxes on your hardware.
2047 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can
2050 CONFIG_SYS_I2C_MAX_HOPS
2051 define how many muxes are maximal consecutively connected
2052 on one i2c bus. If you not use i2c muxes, omit this
2055 CONFIG_SYS_I2C_BUSES
2056 hold a list of busses you want to use, only used if
2057 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example
2058 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and
2059 CONFIG_SYS_NUM_I2C_BUSES = 9:
2061 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \
2062 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \
2063 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \
2064 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \
2065 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \
2066 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \
2067 {1, {I2C_NULL_HOP}}, \
2068 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \
2069 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \
2073 bus 0 on adapter 0 without a mux
2074 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1
2075 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2
2076 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3
2077 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4
2078 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5
2079 bus 6 on adapter 1 without a mux
2080 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1
2081 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2
2083 If you do not have i2c muxes on your board, omit this define.
2085 - Legacy I2C Support: CONFIG_HARD_I2C
2087 NOTE: It is intended to move drivers to CONFIG_SYS_I2C which
2088 provides the following compelling advantages:
2090 - more than one i2c adapter is usable
2091 - approved multibus support
2092 - better i2c mux support
2094 ** Please consider updating your I2C driver now. **
2096 These enable legacy I2C serial bus commands. Defining
2097 CONFIG_HARD_I2C will include the appropriate I2C driver
2098 for the selected CPU.
2100 This will allow you to use i2c commands at the u-boot
2101 command line (as long as you set CONFIG_CMD_I2C in
2102 CONFIG_COMMANDS) and communicate with i2c based realtime
2103 clock chips. See common/cmd_i2c.c for a description of the
2104 command line interface.
2106 CONFIG_HARD_I2C selects a hardware I2C controller.
2108 There are several other quantities that must also be
2109 defined when you define CONFIG_HARD_I2C.
2111 In both cases you will need to define CONFIG_SYS_I2C_SPEED
2112 to be the frequency (in Hz) at which you wish your i2c bus
2113 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie
2114 the CPU's i2c node address).
2116 Now, the u-boot i2c code for the mpc8xx
2117 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node
2118 and so its address should therefore be cleared to 0 (See,
2119 eg, MPC823e User's Manual p.16-473). So, set
2120 CONFIG_SYS_I2C_SLAVE to 0.
2122 CONFIG_SYS_I2C_INIT_MPC5XXX
2124 When a board is reset during an i2c bus transfer
2125 chips might think that the current transfer is still
2126 in progress. Reset the slave devices by sending start
2127 commands until the slave device responds.
2129 That's all that's required for CONFIG_HARD_I2C.
2131 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT)
2132 then the following macros need to be defined (examples are
2133 from include/configs/lwmon.h):
2137 (Optional). Any commands necessary to enable the I2C
2138 controller or configure ports.
2140 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
2144 (Only for MPC8260 CPU). The I/O port to use (the code
2145 assumes both bits are on the same port). Valid values
2146 are 0..3 for ports A..D.
2150 The code necessary to make the I2C data line active
2151 (driven). If the data line is open collector, this
2154 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
2158 The code necessary to make the I2C data line tri-stated
2159 (inactive). If the data line is open collector, this
2162 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
2166 Code that returns true if the I2C data line is high,
2169 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
2173 If <bit> is true, sets the I2C data line high. If it
2174 is false, it clears it (low).
2176 eg: #define I2C_SDA(bit) \
2177 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
2178 else immr->im_cpm.cp_pbdat &= ~PB_SDA
2182 If <bit> is true, sets the I2C clock line high. If it
2183 is false, it clears it (low).
2185 eg: #define I2C_SCL(bit) \
2186 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
2187 else immr->im_cpm.cp_pbdat &= ~PB_SCL
2191 This delay is invoked four times per clock cycle so this
2192 controls the rate of data transfer. The data rate thus
2193 is 1 / (I2C_DELAY * 4). Often defined to be something
2196 #define I2C_DELAY udelay(2)
2198 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
2200 If your arch supports the generic GPIO framework (asm/gpio.h),
2201 then you may alternatively define the two GPIOs that are to be
2202 used as SCL / SDA. Any of the previous I2C_xxx macros will
2203 have GPIO-based defaults assigned to them as appropriate.
2205 You should define these to the GPIO value as given directly to
2206 the generic GPIO functions.
2208 CONFIG_SYS_I2C_INIT_BOARD
2210 When a board is reset during an i2c bus transfer
2211 chips might think that the current transfer is still
2212 in progress. On some boards it is possible to access
2213 the i2c SCLK line directly, either by using the
2214 processor pin as a GPIO or by having a second pin
2215 connected to the bus. If this option is defined a
2216 custom i2c_init_board() routine in boards/xxx/board.c
2217 is run early in the boot sequence.
2219 CONFIG_SYS_I2C_BOARD_LATE_INIT
2221 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is
2222 defined a custom i2c_board_late_init() routine in
2223 boards/xxx/board.c is run AFTER the operations in i2c_init()
2224 is completed. This callpoint can be used to unreset i2c bus
2225 using CPU i2c controller register accesses for CPUs whose i2c
2226 controller provide such a method. It is called at the end of
2227 i2c_init() to allow i2c_init operations to setup the i2c bus
2228 controller on the CPU (e.g. setting bus speed & slave address).
2230 CONFIG_I2CFAST (PPC405GP|PPC405EP only)
2232 This option enables configuration of bi_iic_fast[] flags
2233 in u-boot bd_info structure based on u-boot environment
2234 variable "i2cfast". (see also i2cfast)
2236 CONFIG_I2C_MULTI_BUS
2238 This option allows the use of multiple I2C buses, each of which
2239 must have a controller. At any point in time, only one bus is
2240 active. To switch to a different bus, use the 'i2c dev' command.
2241 Note that bus numbering is zero-based.
2243 CONFIG_SYS_I2C_NOPROBES
2245 This option specifies a list of I2C devices that will be skipped
2246 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
2247 is set, specify a list of bus-device pairs. Otherwise, specify
2248 a 1D array of device addresses
2251 #undef CONFIG_I2C_MULTI_BUS
2252 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
2254 will skip addresses 0x50 and 0x68 on a board with one I2C bus
2256 #define CONFIG_I2C_MULTI_BUS
2257 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
2259 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
2261 CONFIG_SYS_SPD_BUS_NUM
2263 If defined, then this indicates the I2C bus number for DDR SPD.
2264 If not defined, then U-Boot assumes that SPD is on I2C bus 0.
2266 CONFIG_SYS_RTC_BUS_NUM
2268 If defined, then this indicates the I2C bus number for the RTC.
2269 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
2271 CONFIG_SYS_DTT_BUS_NUM
2273 If defined, then this indicates the I2C bus number for the DTT.
2274 If not defined, then U-Boot assumes that DTT is on I2C bus 0.
2276 CONFIG_SYS_I2C_DTT_ADDR:
2278 If defined, specifies the I2C address of the DTT device.
2279 If not defined, then U-Boot uses predefined value for
2280 specified DTT device.
2282 CONFIG_SOFT_I2C_READ_REPEATED_START
2284 defining this will force the i2c_read() function in
2285 the soft_i2c driver to perform an I2C repeated start
2286 between writing the address pointer and reading the
2287 data. If this define is omitted the default behaviour
2288 of doing a stop-start sequence will be used. Most I2C
2289 devices can use either method, but some require one or
2292 - SPI Support: CONFIG_SPI
2294 Enables SPI driver (so far only tested with
2295 SPI EEPROM, also an instance works with Crystal A/D and
2296 D/As on the SACSng board)
2300 Enables the driver for SPI controller on SuperH. Currently
2301 only SH7757 is supported.
2305 Enables extended (16-bit) SPI EEPROM addressing.
2306 (symmetrical to CONFIG_I2C_X)
2310 Enables a software (bit-bang) SPI driver rather than
2311 using hardware support. This is a general purpose
2312 driver that only requires three general I/O port pins
2313 (two outputs, one input) to function. If this is
2314 defined, the board configuration must define several
2315 SPI configuration items (port pins to use, etc). For
2316 an example, see include/configs/sacsng.h.
2320 Enables a hardware SPI driver for general-purpose reads
2321 and writes. As with CONFIG_SOFT_SPI, the board configuration
2322 must define a list of chip-select function pointers.
2323 Currently supported on some MPC8xxx processors. For an
2324 example, see include/configs/mpc8349emds.h.
2328 Enables the driver for the SPI controllers on i.MX and MXC
2329 SoCs. Currently i.MX31/35/51 are supported.
2331 - FPGA Support: CONFIG_FPGA
2333 Enables FPGA subsystem.
2335 CONFIG_FPGA_<vendor>
2337 Enables support for specific chip vendors.
2340 CONFIG_FPGA_<family>
2342 Enables support for FPGA family.
2343 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
2347 Specify the number of FPGA devices to support.
2349 CONFIG_SYS_FPGA_PROG_FEEDBACK
2351 Enable printing of hash marks during FPGA configuration.
2353 CONFIG_SYS_FPGA_CHECK_BUSY
2355 Enable checks on FPGA configuration interface busy
2356 status by the configuration function. This option
2357 will require a board or device specific function to
2362 If defined, a function that provides delays in the FPGA
2363 configuration driver.
2365 CONFIG_SYS_FPGA_CHECK_CTRLC
2366 Allow Control-C to interrupt FPGA configuration
2368 CONFIG_SYS_FPGA_CHECK_ERROR
2370 Check for configuration errors during FPGA bitfile
2371 loading. For example, abort during Virtex II
2372 configuration if the INIT_B line goes low (which
2373 indicated a CRC error).
2375 CONFIG_SYS_FPGA_WAIT_INIT
2377 Maximum time to wait for the INIT_B line to deassert
2378 after PROB_B has been deasserted during a Virtex II
2379 FPGA configuration sequence. The default time is 500
2382 CONFIG_SYS_FPGA_WAIT_BUSY
2384 Maximum time to wait for BUSY to deassert during
2385 Virtex II FPGA configuration. The default is 5 ms.
2387 CONFIG_SYS_FPGA_WAIT_CONFIG
2389 Time to wait after FPGA configuration. The default is
2392 - Configuration Management:
2395 If defined, this string will be added to the U-Boot
2396 version information (U_BOOT_VERSION)
2398 - Vendor Parameter Protection:
2400 U-Boot considers the values of the environment
2401 variables "serial#" (Board Serial Number) and
2402 "ethaddr" (Ethernet Address) to be parameters that
2403 are set once by the board vendor / manufacturer, and
2404 protects these variables from casual modification by
2405 the user. Once set, these variables are read-only,
2406 and write or delete attempts are rejected. You can
2407 change this behaviour:
2409 If CONFIG_ENV_OVERWRITE is #defined in your config
2410 file, the write protection for vendor parameters is
2411 completely disabled. Anybody can change or delete
2414 Alternatively, if you #define _both_ CONFIG_ETHADDR
2415 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
2416 Ethernet address is installed in the environment,
2417 which can be changed exactly ONCE by the user. [The
2418 serial# is unaffected by this, i. e. it remains
2421 The same can be accomplished in a more flexible way
2422 for any variable by configuring the type of access
2423 to allow for those variables in the ".flags" variable
2424 or define CONFIG_ENV_FLAGS_LIST_STATIC.
2429 Define this variable to enable the reservation of
2430 "protected RAM", i. e. RAM which is not overwritten
2431 by U-Boot. Define CONFIG_PRAM to hold the number of
2432 kB you want to reserve for pRAM. You can overwrite
2433 this default value by defining an environment
2434 variable "pram" to the number of kB you want to
2435 reserve. Note that the board info structure will
2436 still show the full amount of RAM. If pRAM is
2437 reserved, a new environment variable "mem" will
2438 automatically be defined to hold the amount of
2439 remaining RAM in a form that can be passed as boot
2440 argument to Linux, for instance like that:
2442 setenv bootargs ... mem=\${mem}
2445 This way you can tell Linux not to use this memory,
2446 either, which results in a memory region that will
2447 not be affected by reboots.
2449 *WARNING* If your board configuration uses automatic
2450 detection of the RAM size, you must make sure that
2451 this memory test is non-destructive. So far, the
2452 following board configurations are known to be
2455 IVMS8, IVML24, SPD8xx, TQM8xxL,
2456 HERMES, IP860, RPXlite, LWMON,
2459 - Access to physical memory region (> 4GB)
2460 Some basic support is provided for operations on memory not
2461 normally accessible to U-Boot - e.g. some architectures
2462 support access to more than 4GB of memory on 32-bit
2463 machines using physical address extension or similar.
2464 Define CONFIG_PHYSMEM to access this basic support, which
2465 currently only supports clearing the memory.
2470 Define this variable to stop the system in case of a
2471 fatal error, so that you have to reset it manually.
2472 This is probably NOT a good idea for an embedded
2473 system where you want the system to reboot
2474 automatically as fast as possible, but it may be
2475 useful during development since you can try to debug
2476 the conditions that lead to the situation.
2478 CONFIG_NET_RETRY_COUNT
2480 This variable defines the number of retries for
2481 network operations like ARP, RARP, TFTP, or BOOTP
2482 before giving up the operation. If not defined, a
2483 default value of 5 is used.
2487 Timeout waiting for an ARP reply in milliseconds.
2491 Timeout in milliseconds used in NFS protocol.
2492 If you encounter "ERROR: Cannot umount" in nfs command,
2493 try longer timeout such as
2494 #define CONFIG_NFS_TIMEOUT 10000UL
2496 - Command Interpreter:
2497 CONFIG_AUTO_COMPLETE
2499 Enable auto completion of commands using TAB.
2501 Note that this feature has NOT been implemented yet
2502 for the "hush" shell.
2505 CONFIG_SYS_HUSH_PARSER
2507 Define this variable to enable the "hush" shell (from
2508 Busybox) as command line interpreter, thus enabling
2509 powerful command line syntax like
2510 if...then...else...fi conditionals or `&&' and '||'
2511 constructs ("shell scripts").
2513 If undefined, you get the old, much simpler behaviour
2514 with a somewhat smaller memory footprint.
2517 CONFIG_SYS_PROMPT_HUSH_PS2
2519 This defines the secondary prompt string, which is
2520 printed when the command interpreter needs more input
2521 to complete a command. Usually "> ".
2525 In the current implementation, the local variables
2526 space and global environment variables space are
2527 separated. Local variables are those you define by
2528 simply typing `name=value'. To access a local
2529 variable later on, you have write `$name' or
2530 `${name}'; to execute the contents of a variable
2531 directly type `$name' at the command prompt.
2533 Global environment variables are those you use
2534 setenv/printenv to work with. To run a command stored
2535 in such a variable, you need to use the run command,
2536 and you must not use the '$' sign to access them.
2538 To store commands and special characters in a
2539 variable, please use double quotation marks
2540 surrounding the whole text of the variable, instead
2541 of the backslashes before semicolons and special
2544 - Commandline Editing and History:
2545 CONFIG_CMDLINE_EDITING
2547 Enable editing and History functions for interactive
2548 commandline input operations
2550 - Default Environment:
2551 CONFIG_EXTRA_ENV_SETTINGS
2553 Define this to contain any number of null terminated
2554 strings (variable = value pairs) that will be part of
2555 the default environment compiled into the boot image.
2557 For example, place something like this in your
2558 board's config file:
2560 #define CONFIG_EXTRA_ENV_SETTINGS \
2564 Warning: This method is based on knowledge about the
2565 internal format how the environment is stored by the
2566 U-Boot code. This is NOT an official, exported
2567 interface! Although it is unlikely that this format
2568 will change soon, there is no guarantee either.
2569 You better know what you are doing here.
2571 Note: overly (ab)use of the default environment is
2572 discouraged. Make sure to check other ways to preset
2573 the environment like the "source" command or the
2576 CONFIG_ENV_VARS_UBOOT_CONFIG
2578 Define this in order to add variables describing the
2579 U-Boot build configuration to the default environment.
2580 These will be named arch, cpu, board, vendor, and soc.
2582 Enabling this option will cause the following to be defined:
2590 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG
2592 Define this in order to add variables describing certain
2593 run-time determined information about the hardware to the
2594 environment. These will be named board_name, board_rev.
2596 CONFIG_DELAY_ENVIRONMENT
2598 Normally the environment is loaded when the board is
2599 intialised so that it is available to U-Boot. This inhibits
2600 that so that the environment is not available until
2601 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL
2602 this is instead controlled by the value of
2603 /config/load-environment.
2605 - DataFlash Support:
2606 CONFIG_HAS_DATAFLASH
2608 Defining this option enables DataFlash features and
2609 allows to read/write in Dataflash via the standard
2612 - Serial Flash support
2615 Defining this option enables SPI flash commands
2616 'sf probe/read/write/erase/update'.
2618 Usage requires an initial 'probe' to define the serial
2619 flash parameters, followed by read/write/erase/update
2622 The following defaults may be provided by the platform
2623 to handle the common case when only a single serial
2624 flash is present on the system.
2626 CONFIG_SF_DEFAULT_BUS Bus identifier
2627 CONFIG_SF_DEFAULT_CS Chip-select
2628 CONFIG_SF_DEFAULT_MODE (see include/spi.h)
2629 CONFIG_SF_DEFAULT_SPEED in Hz
2633 Define this option to include a destructive SPI flash
2636 CONFIG_SPI_FLASH_BAR Ban/Extended Addr Reg
2638 Define this option to use the Bank addr/Extended addr
2639 support on SPI flashes which has size > 16Mbytes.
2641 - SystemACE Support:
2644 Adding this option adds support for Xilinx SystemACE
2645 chips attached via some sort of local bus. The address
2646 of the chip must also be defined in the
2647 CONFIG_SYS_SYSTEMACE_BASE macro. For example:
2649 #define CONFIG_SYSTEMACE
2650 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000
2652 When SystemACE support is added, the "ace" device type
2653 becomes available to the fat commands, i.e. fatls.
2655 - TFTP Fixed UDP Port:
2658 If this is defined, the environment variable tftpsrcp
2659 is used to supply the TFTP UDP source port value.
2660 If tftpsrcp isn't defined, the normal pseudo-random port
2661 number generator is used.
2663 Also, the environment variable tftpdstp is used to supply
2664 the TFTP UDP destination port value. If tftpdstp isn't
2665 defined, the normal port 69 is used.
2667 The purpose for tftpsrcp is to allow a TFTP server to
2668 blindly start the TFTP transfer using the pre-configured
2669 target IP address and UDP port. This has the effect of
2670 "punching through" the (Windows XP) firewall, allowing
2671 the remainder of the TFTP transfer to proceed normally.
2672 A better solution is to properly configure the firewall,
2673 but sometimes that is not allowed.
2678 This enables a generic 'hash' command which can produce
2679 hashes / digests from a few algorithms (e.g. SHA1, SHA256).
2683 Enable the hash verify command (hash -v). This adds to code
2686 CONFIG_SHA1 - support SHA1 hashing
2687 CONFIG_SHA256 - support SHA256 hashing
2689 Note: There is also a sha1sum command, which should perhaps
2690 be deprecated in favour of 'hash sha1'.
2692 - Freescale i.MX specific commands:
2693 CONFIG_CMD_HDMIDETECT
2694 This enables 'hdmidet' command which returns true if an
2695 HDMI monitor is detected. This command is i.MX 6 specific.
2698 This enables the 'bmode' (bootmode) command for forcing
2699 a boot from specific media.
2701 This is useful for forcing the ROM's usb downloader to
2702 activate upon a watchdog reset which is nice when iterating
2703 on U-Boot. Using the reset button or running bmode normal
2704 will set it back to normal. This command currently
2705 supports i.MX53 and i.MX6.
2710 This enables the RSA algorithm used for FIT image verification
2711 in U-Boot. See doc/uImage/signature for more information.
2713 The signing part is build into mkimage regardless of this
2717 - Show boot progress:
2718 CONFIG_SHOW_BOOT_PROGRESS
2720 Defining this option allows to add some board-
2721 specific code (calling a user-provided function
2722 "show_boot_progress(int)") that enables you to show
2723 the system's boot progress on some display (for
2724 example, some LED's) on your board. At the moment,
2725 the following checkpoints are implemented:
2727 - Detailed boot stage timing
2729 Define this option to get detailed timing of each stage
2730 of the boot process.
2732 CONFIG_BOOTSTAGE_USER_COUNT
2733 This is the number of available user bootstage records.
2734 Each time you call bootstage_mark(BOOTSTAGE_ID_ALLOC, ...)
2735 a new ID will be allocated from this stash. If you exceed
2736 the limit, recording will stop.
2738 CONFIG_BOOTSTAGE_REPORT
2739 Define this to print a report before boot, similar to this:
2741 Timer summary in microseconds:
2744 3,575,678 3,575,678 board_init_f start
2745 3,575,695 17 arch_cpu_init A9
2746 3,575,777 82 arch_cpu_init done
2747 3,659,598 83,821 board_init_r start
2748 3,910,375 250,777 main_loop
2749 29,916,167 26,005,792 bootm_start
2750 30,361,327 445,160 start_kernel
2752 CONFIG_CMD_BOOTSTAGE
2753 Add a 'bootstage' command which supports printing a report
2754 and un/stashing of bootstage data.
2756 CONFIG_BOOTSTAGE_FDT
2757 Stash the bootstage information in the FDT. A root 'bootstage'
2758 node is created with each bootstage id as a child. Each child
2759 has a 'name' property and either 'mark' containing the
2760 mark time in microsecond, or 'accum' containing the
2761 accumulated time for that bootstage id in microseconds.
2766 name = "board_init_f";
2775 Code in the Linux kernel can find this in /proc/devicetree.
2777 Legacy uImage format:
2780 1 common/cmd_bootm.c before attempting to boot an image
2781 -1 common/cmd_bootm.c Image header has bad magic number
2782 2 common/cmd_bootm.c Image header has correct magic number
2783 -2 common/cmd_bootm.c Image header has bad checksum
2784 3 common/cmd_bootm.c Image header has correct checksum
2785 -3 common/cmd_bootm.c Image data has bad checksum
2786 4 common/cmd_bootm.c Image data has correct checksum
2787 -4 common/cmd_bootm.c Image is for unsupported architecture
2788 5 common/cmd_bootm.c Architecture check OK
2789 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
2790 6 common/cmd_bootm.c Image Type check OK
2791 -6 common/cmd_bootm.c gunzip uncompression error
2792 -7 common/cmd_bootm.c Unimplemented compression type
2793 7 common/cmd_bootm.c Uncompression OK
2794 8 common/cmd_bootm.c No uncompress/copy overwrite error
2795 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
2797 9 common/image.c Start initial ramdisk verification
2798 -10 common/image.c Ramdisk header has bad magic number
2799 -11 common/image.c Ramdisk header has bad checksum
2800 10 common/image.c Ramdisk header is OK
2801 -12 common/image.c Ramdisk data has bad checksum
2802 11 common/image.c Ramdisk data has correct checksum
2803 12 common/image.c Ramdisk verification complete, start loading
2804 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
2805 13 common/image.c Start multifile image verification
2806 14 common/image.c No initial ramdisk, no multifile, continue.
2808 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
2810 -30 arch/powerpc/lib/board.c Fatal error, hang the system
2811 -31 post/post.c POST test failed, detected by post_output_backlog()
2812 -32 post/post.c POST test failed, detected by post_run_single()
2814 34 common/cmd_doc.c before loading a Image from a DOC device
2815 -35 common/cmd_doc.c Bad usage of "doc" command
2816 35 common/cmd_doc.c correct usage of "doc" command
2817 -36 common/cmd_doc.c No boot device
2818 36 common/cmd_doc.c correct boot device
2819 -37 common/cmd_doc.c Unknown Chip ID on boot device
2820 37 common/cmd_doc.c correct chip ID found, device available
2821 -38 common/cmd_doc.c Read Error on boot device
2822 38 common/cmd_doc.c reading Image header from DOC device OK
2823 -39 common/cmd_doc.c Image header has bad magic number
2824 39 common/cmd_doc.c Image header has correct magic number
2825 -40 common/cmd_doc.c Error reading Image from DOC device
2826 40 common/cmd_doc.c Image header has correct magic number
2827 41 common/cmd_ide.c before loading a Image from a IDE device
2828 -42 common/cmd_ide.c Bad usage of "ide" command
2829 42 common/cmd_ide.c correct usage of "ide" command
2830 -43 common/cmd_ide.c No boot device
2831 43 common/cmd_ide.c boot device found
2832 -44 common/cmd_ide.c Device not available
2833 44 common/cmd_ide.c Device available
2834 -45 common/cmd_ide.c wrong partition selected
2835 45 common/cmd_ide.c partition selected
2836 -46 common/cmd_ide.c Unknown partition table
2837 46 common/cmd_ide.c valid partition table found
2838 -47 common/cmd_ide.c Invalid partition type
2839 47 common/cmd_ide.c correct partition type
2840 -48 common/cmd_ide.c Error reading Image Header on boot device
2841 48 common/cmd_ide.c reading Image Header from IDE device OK
2842 -49 common/cmd_ide.c Image header has bad magic number
2843 49 common/cmd_ide.c Image header has correct magic number
2844 -50 common/cmd_ide.c Image header has bad checksum
2845 50 common/cmd_ide.c Image header has correct checksum
2846 -51 common/cmd_ide.c Error reading Image from IDE device
2847 51 common/cmd_ide.c reading Image from IDE device OK
2848 52 common/cmd_nand.c before loading a Image from a NAND device
2849 -53 common/cmd_nand.c Bad usage of "nand" command
2850 53 common/cmd_nand.c correct usage of "nand" command
2851 -54 common/cmd_nand.c No boot device
2852 54 common/cmd_nand.c boot device found
2853 -55 common/cmd_nand.c Unknown Chip ID on boot device
2854 55 common/cmd_nand.c correct chip ID found, device available
2855 -56 common/cmd_nand.c Error reading Image Header on boot device
2856 56 common/cmd_nand.c reading Image Header from NAND device OK
2857 -57 common/cmd_nand.c Image header has bad magic number
2858 57 common/cmd_nand.c Image header has correct magic number
2859 -58 common/cmd_nand.c Error reading Image from NAND device
2860 58 common/cmd_nand.c reading Image from NAND device OK
2862 -60 common/env_common.c Environment has a bad CRC, using default
2864 64 net/eth.c starting with Ethernet configuration.
2865 -64 net/eth.c no Ethernet found.
2866 65 net/eth.c Ethernet found.
2868 -80 common/cmd_net.c usage wrong
2869 80 common/cmd_net.c before calling NetLoop()
2870 -81 common/cmd_net.c some error in NetLoop() occurred
2871 81 common/cmd_net.c NetLoop() back without error
2872 -82 common/cmd_net.c size == 0 (File with size 0 loaded)
2873 82 common/cmd_net.c trying automatic boot
2874 83 common/cmd_net.c running "source" command
2875 -83 common/cmd_net.c some error in automatic boot or "source" command
2876 84 common/cmd_net.c end without errors
2881 100 common/cmd_bootm.c Kernel FIT Image has correct format
2882 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
2883 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
2884 -101 common/cmd_bootm.c Can't get configuration for kernel subimage
2885 102 common/cmd_bootm.c Kernel unit name specified
2886 -103 common/cmd_bootm.c Can't get kernel subimage node offset
2887 103 common/cmd_bootm.c Found configuration node
2888 104 common/cmd_bootm.c Got kernel subimage node offset
2889 -104 common/cmd_bootm.c Kernel subimage hash verification failed
2890 105 common/cmd_bootm.c Kernel subimage hash verification OK
2891 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
2892 106 common/cmd_bootm.c Architecture check OK
2893 -106 common/cmd_bootm.c Kernel subimage has wrong type
2894 107 common/cmd_bootm.c Kernel subimage type OK
2895 -107 common/cmd_bootm.c Can't get kernel subimage data/size
2896 108 common/cmd_bootm.c Got kernel subimage data/size
2897 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
2898 -109 common/cmd_bootm.c Can't get kernel subimage type
2899 -110 common/cmd_bootm.c Can't get kernel subimage comp
2900 -111 common/cmd_bootm.c Can't get kernel subimage os
2901 -112 common/cmd_bootm.c Can't get kernel subimage load address
2902 -113 common/cmd_bootm.c Image uncompress/copy overwrite error
2904 120 common/image.c Start initial ramdisk verification
2905 -120 common/image.c Ramdisk FIT image has incorrect format
2906 121 common/image.c Ramdisk FIT image has correct format
2907 122 common/image.c No ramdisk subimage unit name, using configuration
2908 -122 common/image.c Can't get configuration for ramdisk subimage
2909 123 common/image.c Ramdisk unit name specified
2910 -124 common/image.c Can't get ramdisk subimage node offset
2911 125 common/image.c Got ramdisk subimage node offset
2912 -125 common/image.c Ramdisk subimage hash verification failed
2913 126 common/image.c Ramdisk subimage hash verification OK
2914 -126 common/image.c Ramdisk subimage for unsupported architecture
2915 127 common/image.c Architecture check OK
2916 -127 common/image.c Can't get ramdisk subimage data/size
2917 128 common/image.c Got ramdisk subimage data/size
2918 129 common/image.c Can't get ramdisk load address
2919 -129 common/image.c Got ramdisk load address
2921 -130 common/cmd_doc.c Incorrect FIT image format
2922 131 common/cmd_doc.c FIT image format OK
2924 -140 common/cmd_ide.c Incorrect FIT image format
2925 141 common/cmd_ide.c FIT image format OK
2927 -150 common/cmd_nand.c Incorrect FIT image format
2928 151 common/cmd_nand.c FIT image format OK
2930 - FIT image support:
2932 Enable support for the FIT uImage format.
2934 CONFIG_FIT_BEST_MATCH
2935 When no configuration is explicitly selected, default to the
2936 one whose fdt's compatibility field best matches that of
2937 U-Boot itself. A match is considered "best" if it matches the
2938 most specific compatibility entry of U-Boot's fdt's root node.
2939 The order of entries in the configuration's fdt is ignored.
2941 CONFIG_FIT_SIGNATURE
2942 This option enables signature verification of FIT uImages,
2943 using a hash signed and verified using RSA. See
2944 doc/uImage.FIT/signature.txt for more details.
2946 - Standalone program support:
2947 CONFIG_STANDALONE_LOAD_ADDR
2949 This option defines a board specific value for the
2950 address where standalone program gets loaded, thus
2951 overwriting the architecture dependent default
2954 - Frame Buffer Address:
2957 Define CONFIG_FB_ADDR if you want to use specific
2958 address for frame buffer. This is typically the case
2959 when using a graphics controller has separate video
2960 memory. U-Boot will then place the frame buffer at
2961 the given address instead of dynamically reserving it
2962 in system RAM by calling lcd_setmem(), which grabs
2963 the memory for the frame buffer depending on the
2964 configured panel size.
2966 Please see board_init_f function.
2968 - Automatic software updates via TFTP server
2970 CONFIG_UPDATE_TFTP_CNT_MAX
2971 CONFIG_UPDATE_TFTP_MSEC_MAX
2973 These options enable and control the auto-update feature;
2974 for a more detailed description refer to doc/README.update.
2976 - MTD Support (mtdparts command, UBI support)
2979 Adds the MTD device infrastructure from the Linux kernel.
2980 Needed for mtdparts command support.
2982 CONFIG_MTD_PARTITIONS
2984 Adds the MTD partitioning infrastructure from the Linux
2985 kernel. Needed for UBI support.
2990 Adds commands for interacting with MTD partitions formatted
2991 with the UBI flash translation layer
2993 Requires also defining CONFIG_RBTREE
2995 CONFIG_UBI_SILENCE_MSG
2997 Make the verbose messages from UBI stop printing. This leaves
2998 warnings and errors enabled.
3003 Adds commands for interacting with UBI volumes formatted as
3004 UBIFS. UBIFS is read-only in u-boot.
3006 Requires UBI support as well as CONFIG_LZO
3008 CONFIG_UBIFS_SILENCE_MSG
3010 Make the verbose messages from UBIFS stop printing. This leaves
3011 warnings and errors enabled.
3015 Enable building of SPL globally.
3018 LDSCRIPT for linking the SPL binary.
3020 CONFIG_SPL_MAX_FOOTPRINT
3021 Maximum size in memory allocated to the SPL, BSS included.
3022 When defined, the linker checks that the actual memory
3023 used by SPL from _start to __bss_end does not exceed it.
3024 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
3025 must not be both defined at the same time.
3028 Maximum size of the SPL image (text, data, rodata, and
3029 linker lists sections), BSS excluded.
3030 When defined, the linker checks that the actual size does
3033 CONFIG_SPL_TEXT_BASE
3034 TEXT_BASE for linking the SPL binary.
3036 CONFIG_SPL_RELOC_TEXT_BASE
3037 Address to relocate to. If unspecified, this is equal to
3038 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done).
3040 CONFIG_SPL_BSS_START_ADDR
3041 Link address for the BSS within the SPL binary.
3043 CONFIG_SPL_BSS_MAX_SIZE
3044 Maximum size in memory allocated to the SPL BSS.
3045 When defined, the linker checks that the actual memory used
3046 by SPL from __bss_start to __bss_end does not exceed it.
3047 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
3048 must not be both defined at the same time.
3051 Adress of the start of the stack SPL will use
3053 CONFIG_SPL_RELOC_STACK
3054 Adress of the start of the stack SPL will use after
3055 relocation. If unspecified, this is equal to
3058 CONFIG_SYS_SPL_MALLOC_START
3059 Starting address of the malloc pool used in SPL.
3061 CONFIG_SYS_SPL_MALLOC_SIZE
3062 The size of the malloc pool used in SPL.
3064 CONFIG_SPL_FRAMEWORK
3065 Enable the SPL framework under common/. This framework
3066 supports MMC, NAND and YMODEM loading of U-Boot and NAND
3067 NAND loading of the Linux Kernel.
3069 CONFIG_SPL_DISPLAY_PRINT
3070 For ARM, enable an optional function to print more information
3071 about the running system.
3073 CONFIG_SPL_INIT_MINIMAL
3074 Arch init code should be built for a very small image
3076 CONFIG_SPL_LIBCOMMON_SUPPORT
3077 Support for common/libcommon.o in SPL binary
3079 CONFIG_SPL_LIBDISK_SUPPORT
3080 Support for disk/libdisk.o in SPL binary
3082 CONFIG_SPL_I2C_SUPPORT
3083 Support for drivers/i2c/libi2c.o in SPL binary
3085 CONFIG_SPL_GPIO_SUPPORT
3086 Support for drivers/gpio/libgpio.o in SPL binary
3088 CONFIG_SPL_MMC_SUPPORT
3089 Support for drivers/mmc/libmmc.o in SPL binary
3091 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR,
3092 CONFIG_SYS_U_BOOT_MAX_SIZE_SECTORS,
3093 CONFIG_SYS_MMC_SD_FAT_BOOT_PARTITION
3094 Address, size and partition on the MMC to load U-Boot from
3095 when the MMC is being used in raw mode.
3097 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR
3098 Sector to load kernel uImage from when MMC is being
3099 used in raw mode (for Falcon mode)
3101 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR,
3102 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS
3103 Sector and number of sectors to load kernel argument
3104 parameters from when MMC is being used in raw mode
3107 CONFIG_SPL_FAT_SUPPORT
3108 Support for fs/fat/libfat.o in SPL binary
3110 CONFIG_SPL_FAT_LOAD_PAYLOAD_NAME
3111 Filename to read to load U-Boot when reading from FAT
3113 CONFIG_SPL_FAT_LOAD_KERNEL_NAME
3114 Filename to read to load kernel uImage when reading
3115 from FAT (for Falcon mode)
3117 CONFIG_SPL_FAT_LOAD_ARGS_NAME
3118 Filename to read to load kernel argument parameters
3119 when reading from FAT (for Falcon mode)
3121 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND
3122 Set this for NAND SPL on PPC mpc83xx targets, so that
3123 start.S waits for the rest of the SPL to load before
3124 continuing (the hardware starts execution after just
3125 loading the first page rather than the full 4K).
3127 CONFIG_SPL_NAND_BASE
3128 Include nand_base.c in the SPL. Requires
3129 CONFIG_SPL_NAND_DRIVERS.
3131 CONFIG_SPL_NAND_DRIVERS
3132 SPL uses normal NAND drivers, not minimal drivers.
3135 Include standard software ECC in the SPL
3137 CONFIG_SPL_NAND_SIMPLE
3138 Support for NAND boot using simple NAND drivers that
3139 expose the cmd_ctrl() interface.
3141 CONFIG_SPL_MPC8XXX_INIT_DDR_SUPPORT
3142 Set for the SPL on PPC mpc8xxx targets, support for
3143 arch/powerpc/cpu/mpc8xxx/ddr/libddr.o in SPL binary.
3145 CONFIG_SPL_COMMON_INIT_DDR
3146 Set for common ddr init with serial presence detect in
3149 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
3150 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
3151 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
3152 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE,
3153 CONFIG_SYS_NAND_ECCBYTES
3154 Defines the size and behavior of the NAND that SPL uses
3157 CONFIG_SYS_NAND_U_BOOT_OFFS
3158 Location in NAND to read U-Boot from
3160 CONFIG_SYS_NAND_U_BOOT_DST
3161 Location in memory to load U-Boot to
3163 CONFIG_SYS_NAND_U_BOOT_SIZE
3164 Size of image to load
3166 CONFIG_SYS_NAND_U_BOOT_START
3167 Entry point in loaded image to jump to
3169 CONFIG_SYS_NAND_HW_ECC_OOBFIRST
3170 Define this if you need to first read the OOB and then the
3171 data. This is used for example on davinci plattforms.
3173 CONFIG_SPL_OMAP3_ID_NAND
3174 Support for an OMAP3-specific set of functions to return the
3175 ID and MFR of the first attached NAND chip, if present.
3177 CONFIG_SPL_SERIAL_SUPPORT
3178 Support for drivers/serial/libserial.o in SPL binary
3180 CONFIG_SPL_SPI_FLASH_SUPPORT
3181 Support for drivers/mtd/spi/libspi_flash.o in SPL binary
3183 CONFIG_SPL_SPI_SUPPORT
3184 Support for drivers/spi/libspi.o in SPL binary
3186 CONFIG_SPL_RAM_DEVICE
3187 Support for running image already present in ram, in SPL binary
3189 CONFIG_SPL_LIBGENERIC_SUPPORT
3190 Support for lib/libgeneric.o in SPL binary
3192 CONFIG_SPL_ENV_SUPPORT
3193 Support for the environment operating in SPL binary
3195 CONFIG_SPL_NET_SUPPORT
3196 Support for the net/libnet.o in SPL binary.
3197 It conflicts with SPL env from storage medium specified by
3198 CONFIG_ENV_IS_xxx but CONFIG_ENV_IS_NOWHERE
3201 Image offset to which the SPL should be padded before appending
3202 the SPL payload. By default, this is defined as
3203 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
3204 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
3205 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
3208 Final target image containing SPL and payload. Some SPLs
3209 use an arch-specific makefile fragment instead, for
3210 example if more than one image needs to be produced.
3212 CONFIG_FIT_SPL_PRINT
3213 Printing information about a FIT image adds quite a bit of
3214 code to SPL. So this is normally disabled in SPL. Use this
3215 option to re-enable it. This will affect the output of the
3216 bootm command when booting a FIT image.
3220 Enable building of TPL globally.
3223 Image offset to which the TPL should be padded before appending
3224 the TPL payload. By default, this is defined as
3225 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
3226 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
3227 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
3232 [so far only for SMDK2400 boards]
3234 - Modem support enable:
3235 CONFIG_MODEM_SUPPORT
3237 - RTS/CTS Flow control enable:
3240 - Modem debug support:
3241 CONFIG_MODEM_SUPPORT_DEBUG
3243 Enables debugging stuff (char screen[1024], dbg())
3244 for modem support. Useful only with BDI2000.
3246 - Interrupt support (PPC):
3248 There are common interrupt_init() and timer_interrupt()
3249 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
3250 for CPU specific initialization. interrupt_init_cpu()
3251 should set decrementer_count to appropriate value. If
3252 CPU resets decrementer automatically after interrupt
3253 (ppc4xx) it should set decrementer_count to zero.
3254 timer_interrupt() calls timer_interrupt_cpu() for CPU
3255 specific handling. If board has watchdog / status_led
3256 / other_activity_monitor it works automatically from
3257 general timer_interrupt().
3261 In the target system modem support is enabled when a
3262 specific key (key combination) is pressed during
3263 power-on. Otherwise U-Boot will boot normally
3264 (autoboot). The key_pressed() function is called from
3265 board_init(). Currently key_pressed() is a dummy
3266 function, returning 1 and thus enabling modem
3269 If there are no modem init strings in the
3270 environment, U-Boot proceed to autoboot; the
3271 previous output (banner, info printfs) will be
3274 See also: doc/README.Modem
3276 Board initialization settings:
3277 ------------------------------
3279 During Initialization u-boot calls a number of board specific functions
3280 to allow the preparation of board specific prerequisites, e.g. pin setup
3281 before drivers are initialized. To enable these callbacks the
3282 following configuration macros have to be defined. Currently this is
3283 architecture specific, so please check arch/your_architecture/lib/board.c
3284 typically in board_init_f() and board_init_r().
3286 - CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
3287 - CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
3288 - CONFIG_BOARD_LATE_INIT: Call board_late_init()
3289 - CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init()
3291 Configuration Settings:
3292 -----------------------
3294 - CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
3295 undefine this when you're short of memory.
3297 - CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
3298 width of the commands listed in the 'help' command output.
3300 - CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
3301 prompt for user input.
3303 - CONFIG_SYS_CBSIZE: Buffer size for input from the Console
3305 - CONFIG_SYS_PBSIZE: Buffer size for Console output
3307 - CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
3309 - CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
3310 the application (usually a Linux kernel) when it is
3313 - CONFIG_SYS_BAUDRATE_TABLE:
3314 List of legal baudrate settings for this board.
3316 - CONFIG_SYS_CONSOLE_INFO_QUIET
3317 Suppress display of console information at boot.
3319 - CONFIG_SYS_CONSOLE_IS_IN_ENV
3320 If the board specific function
3321 extern int overwrite_console (void);
3322 returns 1, the stdin, stderr and stdout are switched to the
3323 serial port, else the settings in the environment are used.
3325 - CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE
3326 Enable the call to overwrite_console().
3328 - CONFIG_SYS_CONSOLE_ENV_OVERWRITE
3329 Enable overwrite of previous console environment settings.
3331 - CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
3332 Begin and End addresses of the area used by the
3335 - CONFIG_SYS_ALT_MEMTEST:
3336 Enable an alternate, more extensive memory test.
3338 - CONFIG_SYS_MEMTEST_SCRATCH:
3339 Scratch address used by the alternate memory test
3340 You only need to set this if address zero isn't writeable
3342 - CONFIG_SYS_MEM_TOP_HIDE (PPC only):
3343 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
3344 this specified memory area will get subtracted from the top
3345 (end) of RAM and won't get "touched" at all by U-Boot. By
3346 fixing up gd->ram_size the Linux kernel should gets passed
3347 the now "corrected" memory size and won't touch it either.
3348 This should work for arch/ppc and arch/powerpc. Only Linux
3349 board ports in arch/powerpc with bootwrapper support that
3350 recalculate the memory size from the SDRAM controller setup
3351 will have to get fixed in Linux additionally.
3353 This option can be used as a workaround for the 440EPx/GRx
3354 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
3357 WARNING: Please make sure that this value is a multiple of
3358 the Linux page size (normally 4k). If this is not the case,
3359 then the end address of the Linux memory will be located at a
3360 non page size aligned address and this could cause major
3363 - CONFIG_SYS_LOADS_BAUD_CHANGE:
3364 Enable temporary baudrate change while serial download
3366 - CONFIG_SYS_SDRAM_BASE:
3367 Physical start address of SDRAM. _Must_ be 0 here.
3369 - CONFIG_SYS_MBIO_BASE:
3370 Physical start address of Motherboard I/O (if using a
3373 - CONFIG_SYS_FLASH_BASE:
3374 Physical start address of Flash memory.
3376 - CONFIG_SYS_MONITOR_BASE:
3377 Physical start address of boot monitor code (set by
3378 make config files to be same as the text base address
3379 (CONFIG_SYS_TEXT_BASE) used when linking) - same as
3380 CONFIG_SYS_FLASH_BASE when booting from flash.
3382 - CONFIG_SYS_MONITOR_LEN:
3383 Size of memory reserved for monitor code, used to
3384 determine _at_compile_time_ (!) if the environment is
3385 embedded within the U-Boot image, or in a separate
3388 - CONFIG_SYS_MALLOC_LEN:
3389 Size of DRAM reserved for malloc() use.
3391 - CONFIG_SYS_BOOTM_LEN:
3392 Normally compressed uImages are limited to an
3393 uncompressed size of 8 MBytes. If this is not enough,
3394 you can define CONFIG_SYS_BOOTM_LEN in your board config file
3395 to adjust this setting to your needs.
3397 - CONFIG_SYS_BOOTMAPSZ:
3398 Maximum size of memory mapped by the startup code of
3399 the Linux kernel; all data that must be processed by
3400 the Linux kernel (bd_info, boot arguments, FDT blob if
3401 used) must be put below this limit, unless "bootm_low"
3402 environment variable is defined and non-zero. In such case
3403 all data for the Linux kernel must be between "bootm_low"
3404 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
3405 variable "bootm_mapsize" will override the value of
3406 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
3407 then the value in "bootm_size" will be used instead.
3409 - CONFIG_SYS_BOOT_RAMDISK_HIGH:
3410 Enable initrd_high functionality. If defined then the
3411 initrd_high feature is enabled and the bootm ramdisk subcommand
3414 - CONFIG_SYS_BOOT_GET_CMDLINE:
3415 Enables allocating and saving kernel cmdline in space between
3416 "bootm_low" and "bootm_low" + BOOTMAPSZ.
3418 - CONFIG_SYS_BOOT_GET_KBD:
3419 Enables allocating and saving a kernel copy of the bd_info in
3420 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
3422 - CONFIG_SYS_MAX_FLASH_BANKS:
3423 Max number of Flash memory banks
3425 - CONFIG_SYS_MAX_FLASH_SECT:
3426 Max number of sectors on a Flash chip
3428 - CONFIG_SYS_FLASH_ERASE_TOUT:
3429 Timeout for Flash erase operations (in ms)
3431 - CONFIG_SYS_FLASH_WRITE_TOUT:
3432 Timeout for Flash write operations (in ms)
3434 - CONFIG_SYS_FLASH_LOCK_TOUT
3435 Timeout for Flash set sector lock bit operation (in ms)
3437 - CONFIG_SYS_FLASH_UNLOCK_TOUT
3438 Timeout for Flash clear lock bits operation (in ms)
3440 - CONFIG_SYS_FLASH_PROTECTION
3441 If defined, hardware flash sectors protection is used
3442 instead of U-Boot software protection.
3444 - CONFIG_SYS_DIRECT_FLASH_TFTP:
3446 Enable TFTP transfers directly to flash memory;
3447 without this option such a download has to be
3448 performed in two steps: (1) download to RAM, and (2)
3449 copy from RAM to flash.
3451 The two-step approach is usually more reliable, since
3452 you can check if the download worked before you erase
3453 the flash, but in some situations (when system RAM is
3454 too limited to allow for a temporary copy of the
3455 downloaded image) this option may be very useful.
3457 - CONFIG_SYS_FLASH_CFI:
3458 Define if the flash driver uses extra elements in the
3459 common flash structure for storing flash geometry.
3461 - CONFIG_FLASH_CFI_DRIVER
3462 This option also enables the building of the cfi_flash driver
3463 in the drivers directory
3465 - CONFIG_FLASH_CFI_MTD
3466 This option enables the building of the cfi_mtd driver
3467 in the drivers directory. The driver exports CFI flash
3470 - CONFIG_SYS_FLASH_USE_BUFFER_WRITE
3471 Use buffered writes to flash.
3473 - CONFIG_FLASH_SPANSION_S29WS_N
3474 s29ws-n MirrorBit flash has non-standard addresses for buffered
3477 - CONFIG_SYS_FLASH_QUIET_TEST
3478 If this option is defined, the common CFI flash doesn't
3479 print it's warning upon not recognized FLASH banks. This
3480 is useful, if some of the configured banks are only
3481 optionally available.
3483 - CONFIG_FLASH_SHOW_PROGRESS
3484 If defined (must be an integer), print out countdown
3485 digits and dots. Recommended value: 45 (9..1) for 80
3486 column displays, 15 (3..1) for 40 column displays.
3488 - CONFIG_FLASH_VERIFY
3489 If defined, the content of the flash (destination) is compared
3490 against the source after the write operation. An error message
3491 will be printed when the contents are not identical.
3492 Please note that this option is useless in nearly all cases,
3493 since such flash programming errors usually are detected earlier
3494 while unprotecting/erasing/programming. Please only enable
3495 this option if you really know what you are doing.
3497 - CONFIG_SYS_RX_ETH_BUFFER:
3498 Defines the number of Ethernet receive buffers. On some
3499 Ethernet controllers it is recommended to set this value
3500 to 8 or even higher (EEPRO100 or 405 EMAC), since all
3501 buffers can be full shortly after enabling the interface
3502 on high Ethernet traffic.
3503 Defaults to 4 if not defined.
3505 - CONFIG_ENV_MAX_ENTRIES
3507 Maximum number of entries in the hash table that is used
3508 internally to store the environment settings. The default
3509 setting is supposed to be generous and should work in most
3510 cases. This setting can be used to tune behaviour; see
3511 lib/hashtable.c for details.
3513 - CONFIG_ENV_FLAGS_LIST_DEFAULT
3514 - CONFIG_ENV_FLAGS_LIST_STATIC
3515 Enable validation of the values given to environment variables when
3516 calling env set. Variables can be restricted to only decimal,
3517 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined,
3518 the variables can also be restricted to IP address or MAC address.
3520 The format of the list is:
3521 type_attribute = [s|d|x|b|i|m]
3522 access_atribute = [a|r|o|c]
3523 attributes = type_attribute[access_atribute]
3524 entry = variable_name[:attributes]
3527 The type attributes are:
3528 s - String (default)
3531 b - Boolean ([1yYtT|0nNfF])
3535 The access attributes are:
3541 - CONFIG_ENV_FLAGS_LIST_DEFAULT
3542 Define this to a list (string) to define the ".flags"
3543 envirnoment variable in the default or embedded environment.
3545 - CONFIG_ENV_FLAGS_LIST_STATIC
3546 Define this to a list (string) to define validation that
3547 should be done if an entry is not found in the ".flags"
3548 environment variable. To override a setting in the static
3549 list, simply add an entry for the same variable name to the
3552 - CONFIG_ENV_ACCESS_IGNORE_FORCE
3553 If defined, don't allow the -f switch to env set override variable
3556 - CONFIG_SYS_GENERIC_BOARD
3557 This selects the architecture-generic board system instead of the
3558 architecture-specific board files. It is intended to move boards
3559 to this new framework over time. Defining this will disable the
3560 arch/foo/lib/board.c file and use common/board_f.c and
3561 common/board_r.c instead. To use this option your architecture
3562 must support it (i.e. must define __HAVE_ARCH_GENERIC_BOARD in
3563 its config.mk file). If you find problems enabling this option on
3564 your board please report the problem and send patches!
3566 - CONFIG_SYS_SYM_OFFSETS
3567 This is set by architectures that use offsets for link symbols
3568 instead of absolute values. So bss_start is obtained using an
3569 offset _bss_start_ofs from CONFIG_SYS_TEXT_BASE, rather than
3570 directly. You should not need to touch this setting.
3572 - CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC (OMAP only)
3573 This is set by OMAP boards for the max time that reset should
3574 be asserted. See doc/README.omap-reset-time for details on how
3575 the value can be calulated on a given board.
3577 The following definitions that deal with the placement and management
3578 of environment data (variable area); in general, we support the
3579 following configurations:
3581 - CONFIG_BUILD_ENVCRC:
3583 Builds up envcrc with the target environment so that external utils
3584 may easily extract it and embed it in final U-Boot images.
3586 - CONFIG_ENV_IS_IN_FLASH:
3588 Define this if the environment is in flash memory.
3590 a) The environment occupies one whole flash sector, which is
3591 "embedded" in the text segment with the U-Boot code. This
3592 happens usually with "bottom boot sector" or "top boot
3593 sector" type flash chips, which have several smaller
3594 sectors at the start or the end. For instance, such a
3595 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
3596 such a case you would place the environment in one of the
3597 4 kB sectors - with U-Boot code before and after it. With
3598 "top boot sector" type flash chips, you would put the
3599 environment in one of the last sectors, leaving a gap
3600 between U-Boot and the environment.
3602 - CONFIG_ENV_OFFSET:
3604 Offset of environment data (variable area) to the
3605 beginning of flash memory; for instance, with bottom boot
3606 type flash chips the second sector can be used: the offset
3607 for this sector is given here.
3609 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE.
3613 This is just another way to specify the start address of
3614 the flash sector containing the environment (instead of
3617 - CONFIG_ENV_SECT_SIZE:
3619 Size of the sector containing the environment.
3622 b) Sometimes flash chips have few, equal sized, BIG sectors.
3623 In such a case you don't want to spend a whole sector for
3628 If you use this in combination with CONFIG_ENV_IS_IN_FLASH
3629 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part
3630 of this flash sector for the environment. This saves
3631 memory for the RAM copy of the environment.
3633 It may also save flash memory if you decide to use this
3634 when your environment is "embedded" within U-Boot code,
3635 since then the remainder of the flash sector could be used
3636 for U-Boot code. It should be pointed out that this is
3637 STRONGLY DISCOURAGED from a robustness point of view:
3638 updating the environment in flash makes it always
3639 necessary to erase the WHOLE sector. If something goes
3640 wrong before the contents has been restored from a copy in
3641 RAM, your target system will be dead.
3643 - CONFIG_ENV_ADDR_REDUND
3644 CONFIG_ENV_SIZE_REDUND
3646 These settings describe a second storage area used to hold
3647 a redundant copy of the environment data, so that there is
3648 a valid backup copy in case there is a power failure during
3649 a "saveenv" operation.
3651 BE CAREFUL! Any changes to the flash layout, and some changes to the
3652 source code will make it necessary to adapt <board>/u-boot.lds*
3656 - CONFIG_ENV_IS_IN_NVRAM:
3658 Define this if you have some non-volatile memory device
3659 (NVRAM, battery buffered SRAM) which you want to use for the
3665 These two #defines are used to determine the memory area you
3666 want to use for environment. It is assumed that this memory
3667 can just be read and written to, without any special
3670 BE CAREFUL! The first access to the environment happens quite early
3671 in U-Boot initalization (when we try to get the setting of for the
3672 console baudrate). You *MUST* have mapped your NVRAM area then, or
3675 Please note that even with NVRAM we still use a copy of the
3676 environment in RAM: we could work on NVRAM directly, but we want to
3677 keep settings there always unmodified except somebody uses "saveenv"
3678 to save the current settings.
3681 - CONFIG_ENV_IS_IN_EEPROM:
3683 Use this if you have an EEPROM or similar serial access
3684 device and a driver for it.
3686 - CONFIG_ENV_OFFSET:
3689 These two #defines specify the offset and size of the
3690 environment area within the total memory of your EEPROM.
3692 - CONFIG_SYS_I2C_EEPROM_ADDR:
3693 If defined, specified the chip address of the EEPROM device.
3694 The default address is zero.
3696 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS:
3697 If defined, the number of bits used to address bytes in a
3698 single page in the EEPROM device. A 64 byte page, for example
3699 would require six bits.
3701 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS:
3702 If defined, the number of milliseconds to delay between
3703 page writes. The default is zero milliseconds.
3705 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN:
3706 The length in bytes of the EEPROM memory array address. Note
3707 that this is NOT the chip address length!
3709 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW:
3710 EEPROM chips that implement "address overflow" are ones
3711 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
3712 address and the extra bits end up in the "chip address" bit
3713 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
3716 Note that we consider the length of the address field to
3717 still be one byte because the extra address bits are hidden
3718 in the chip address.
3720 - CONFIG_SYS_EEPROM_SIZE:
3721 The size in bytes of the EEPROM device.
3723 - CONFIG_ENV_EEPROM_IS_ON_I2C
3724 define this, if you have I2C and SPI activated, and your
3725 EEPROM, which holds the environment, is on the I2C bus.
3727 - CONFIG_I2C_ENV_EEPROM_BUS
3728 if you have an Environment on an EEPROM reached over
3729 I2C muxes, you can define here, how to reach this
3730 EEPROM. For example:
3732 #define CONFIG_I2C_ENV_EEPROM_BUS 1
3734 EEPROM which holds the environment, is reached over
3735 a pca9547 i2c mux with address 0x70, channel 3.
3737 - CONFIG_ENV_IS_IN_DATAFLASH:
3739 Define this if you have a DataFlash memory device which you
3740 want to use for the environment.
3742 - CONFIG_ENV_OFFSET:
3746 These three #defines specify the offset and size of the
3747 environment area within the total memory of your DataFlash placed
3748 at the specified address.
3750 - CONFIG_ENV_IS_IN_REMOTE:
3752 Define this if you have a remote memory space which you
3753 want to use for the local device's environment.
3758 These two #defines specify the address and size of the
3759 environment area within the remote memory space. The
3760 local device can get the environment from remote memory
3761 space by SRIO or PCIE links.
3763 BE CAREFUL! For some special cases, the local device can not use
3764 "saveenv" command. For example, the local device will get the
3765 environment stored in a remote NOR flash by SRIO or PCIE link,
3766 but it can not erase, write this NOR flash by SRIO or PCIE interface.
3768 - CONFIG_ENV_IS_IN_NAND:
3770 Define this if you have a NAND device which you want to use
3771 for the environment.
3773 - CONFIG_ENV_OFFSET:
3776 These two #defines specify the offset and size of the environment
3777 area within the first NAND device. CONFIG_ENV_OFFSET must be
3778 aligned to an erase block boundary.
3780 - CONFIG_ENV_OFFSET_REDUND (optional):
3782 This setting describes a second storage area of CONFIG_ENV_SIZE
3783 size used to hold a redundant copy of the environment data, so
3784 that there is a valid backup copy in case there is a power failure
3785 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be
3786 aligned to an erase block boundary.
3788 - CONFIG_ENV_RANGE (optional):
3790 Specifies the length of the region in which the environment
3791 can be written. This should be a multiple of the NAND device's
3792 block size. Specifying a range with more erase blocks than
3793 are needed to hold CONFIG_ENV_SIZE allows bad blocks within
3794 the range to be avoided.
3796 - CONFIG_ENV_OFFSET_OOB (optional):
3798 Enables support for dynamically retrieving the offset of the
3799 environment from block zero's out-of-band data. The
3800 "nand env.oob" command can be used to record this offset.
3801 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when
3802 using CONFIG_ENV_OFFSET_OOB.
3804 - CONFIG_NAND_ENV_DST
3806 Defines address in RAM to which the nand_spl code should copy the
3807 environment. If redundant environment is used, it will be copied to
3808 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
3810 - CONFIG_ENV_IS_IN_UBI:
3812 Define this if you have an UBI volume that you want to use for the
3813 environment. This has the benefit of wear-leveling the environment
3814 accesses, which is important on NAND.
3816 - CONFIG_ENV_UBI_PART:
3818 Define this to a string that is the mtd partition containing the UBI.
3820 - CONFIG_ENV_UBI_VOLUME:
3822 Define this to the name of the volume that you want to store the
3825 - CONFIG_ENV_UBI_VOLUME_REDUND:
3827 Define this to the name of another volume to store a second copy of
3828 the environment in. This will enable redundant environments in UBI.
3829 It is assumed that both volumes are in the same MTD partition.
3831 - CONFIG_UBI_SILENCE_MSG
3832 - CONFIG_UBIFS_SILENCE_MSG
3834 You will probably want to define these to avoid a really noisy system
3835 when storing the env in UBI.
3837 - CONFIG_ENV_IS_IN_MMC:
3839 Define this if you have an MMC device which you want to use for the
3842 - CONFIG_SYS_MMC_ENV_DEV:
3844 Specifies which MMC device the environment is stored in.
3846 - CONFIG_SYS_MMC_ENV_PART (optional):
3848 Specifies which MMC partition the environment is stored in. If not
3849 set, defaults to partition 0, the user area. Common values might be
3850 1 (first MMC boot partition), 2 (second MMC boot partition).
3852 - CONFIG_ENV_OFFSET:
3855 These two #defines specify the offset and size of the environment
3856 area within the specified MMC device.
3858 If offset is positive (the usual case), it is treated as relative to
3859 the start of the MMC partition. If offset is negative, it is treated
3860 as relative to the end of the MMC partition. This can be useful if
3861 your board may be fitted with different MMC devices, which have
3862 different sizes for the MMC partitions, and you always want the
3863 environment placed at the very end of the partition, to leave the
3864 maximum possible space before it, to store other data.
3866 These two values are in units of bytes, but must be aligned to an
3867 MMC sector boundary.
3869 - CONFIG_ENV_OFFSET_REDUND (optional):
3871 Specifies a second storage area, of CONFIG_ENV_SIZE size, used to
3872 hold a redundant copy of the environment data. This provides a
3873 valid backup copy in case the other copy is corrupted, e.g. due
3874 to a power failure during a "saveenv" operation.
3876 This value may also be positive or negative; this is handled in the
3877 same way as CONFIG_ENV_OFFSET.
3879 This value is also in units of bytes, but must also be aligned to
3880 an MMC sector boundary.
3882 - CONFIG_ENV_SIZE_REDUND (optional):
3884 This value need not be set, even when CONFIG_ENV_OFFSET_REDUND is
3885 set. If this value is set, it must be set to the same value as
3888 - CONFIG_SYS_SPI_INIT_OFFSET
3890 Defines offset to the initial SPI buffer area in DPRAM. The
3891 area is used at an early stage (ROM part) if the environment
3892 is configured to reside in the SPI EEPROM: We need a 520 byte
3893 scratch DPRAM area. It is used between the two initialization
3894 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
3895 to be a good choice since it makes it far enough from the
3896 start of the data area as well as from the stack pointer.
3898 Please note that the environment is read-only until the monitor
3899 has been relocated to RAM and a RAM copy of the environment has been
3900 created; also, when using EEPROM you will have to use getenv_f()
3901 until then to read environment variables.
3903 The environment is protected by a CRC32 checksum. Before the monitor
3904 is relocated into RAM, as a result of a bad CRC you will be working
3905 with the compiled-in default environment - *silently*!!! [This is
3906 necessary, because the first environment variable we need is the
3907 "baudrate" setting for the console - if we have a bad CRC, we don't
3908 have any device yet where we could complain.]
3910 Note: once the monitor has been relocated, then it will complain if
3911 the default environment is used; a new CRC is computed as soon as you
3912 use the "saveenv" command to store a valid environment.
3914 - CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
3915 Echo the inverted Ethernet link state to the fault LED.
3917 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
3918 also needs to be defined.
3920 - CONFIG_SYS_FAULT_MII_ADDR:
3921 MII address of the PHY to check for the Ethernet link state.
3923 - CONFIG_NS16550_MIN_FUNCTIONS:
3924 Define this if you desire to only have use of the NS16550_init
3925 and NS16550_putc functions for the serial driver located at
3926 drivers/serial/ns16550.c. This option is useful for saving
3927 space for already greatly restricted images, including but not
3928 limited to NAND_SPL configurations.
3930 - CONFIG_DISPLAY_BOARDINFO
3931 Display information about the board that U-Boot is running on
3932 when U-Boot starts up. The board function checkboard() is called
3935 - CONFIG_DISPLAY_BOARDINFO_LATE
3936 Similar to the previous option, but display this information
3937 later, once stdio is running and output goes to the LCD, if
3940 Low Level (hardware related) configuration options:
3941 ---------------------------------------------------
3943 - CONFIG_SYS_CACHELINE_SIZE:
3944 Cache Line Size of the CPU.
3946 - CONFIG_SYS_DEFAULT_IMMR:
3947 Default address of the IMMR after system reset.
3949 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
3950 and RPXsuper) to be able to adjust the position of
3951 the IMMR register after a reset.
3953 - CONFIG_SYS_CCSRBAR_DEFAULT:
3954 Default (power-on reset) physical address of CCSR on Freescale
3957 - CONFIG_SYS_CCSRBAR:
3958 Virtual address of CCSR. On a 32-bit build, this is typically
3959 the same value as CONFIG_SYS_CCSRBAR_DEFAULT.
3961 CONFIG_SYS_DEFAULT_IMMR must also be set to this value,
3962 for cross-platform code that uses that macro instead.
3964 - CONFIG_SYS_CCSRBAR_PHYS:
3965 Physical address of CCSR. CCSR can be relocated to a new
3966 physical address, if desired. In this case, this macro should
3967 be set to that address. Otherwise, it should be set to the
3968 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR
3969 is typically relocated on 36-bit builds. It is recommended
3970 that this macro be defined via the _HIGH and _LOW macros:
3972 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH
3973 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW)
3975 - CONFIG_SYS_CCSRBAR_PHYS_HIGH:
3976 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically
3977 either 0 (32-bit build) or 0xF (36-bit build). This macro is
3978 used in assembly code, so it must not contain typecasts or
3979 integer size suffixes (e.g. "ULL").
3981 - CONFIG_SYS_CCSRBAR_PHYS_LOW:
3982 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is
3983 used in assembly code, so it must not contain typecasts or
3984 integer size suffixes (e.g. "ULL").
3986 - CONFIG_SYS_CCSR_DO_NOT_RELOCATE:
3987 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be
3988 forced to a value that ensures that CCSR is not relocated.
3990 - Floppy Disk Support:
3991 CONFIG_SYS_FDC_DRIVE_NUMBER
3993 the default drive number (default value 0)
3995 CONFIG_SYS_ISA_IO_STRIDE
3997 defines the spacing between FDC chipset registers
4000 CONFIG_SYS_ISA_IO_OFFSET
4002 defines the offset of register from address. It
4003 depends on which part of the data bus is connected to
4004 the FDC chipset. (default value 0)
4006 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
4007 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
4010 if CONFIG_SYS_FDC_HW_INIT is defined, then the function
4011 fdc_hw_init() is called at the beginning of the FDC
4012 setup. fdc_hw_init() must be provided by the board
4013 source code. It is used to make hardware dependant
4017 Most IDE controllers were designed to be connected with PCI
4018 interface. Only few of them were designed for AHB interface.
4019 When software is doing ATA command and data transfer to
4020 IDE devices through IDE-AHB controller, some additional
4021 registers accessing to these kind of IDE-AHB controller
4024 - CONFIG_SYS_IMMR: Physical address of the Internal Memory.
4025 DO NOT CHANGE unless you know exactly what you're
4026 doing! (11-4) [MPC8xx/82xx systems only]
4028 - CONFIG_SYS_INIT_RAM_ADDR:
4030 Start address of memory area that can be used for
4031 initial data and stack; please note that this must be
4032 writable memory that is working WITHOUT special
4033 initialization, i. e. you CANNOT use normal RAM which
4034 will become available only after programming the
4035 memory controller and running certain initialization
4038 U-Boot uses the following memory types:
4039 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
4040 - MPC824X: data cache
4041 - PPC4xx: data cache
4043 - CONFIG_SYS_GBL_DATA_OFFSET:
4045 Offset of the initial data structure in the memory
4046 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
4047 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
4048 data is located at the end of the available space
4049 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
4050 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just
4051 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
4052 CONFIG_SYS_GBL_DATA_OFFSET) downward.
4055 On the MPC824X (or other systems that use the data
4056 cache for initial memory) the address chosen for
4057 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
4058 point to an otherwise UNUSED address space between
4059 the top of RAM and the start of the PCI space.
4061 - CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6)
4063 - CONFIG_SYS_SYPCR: System Protection Control (11-9)
4065 - CONFIG_SYS_TBSCR: Time Base Status and Control (11-26)
4067 - CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31)
4069 - CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
4071 - CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
4073 - CONFIG_SYS_OR_TIMING_SDRAM:
4076 - CONFIG_SYS_MAMR_PTA:
4077 periodic timer for refresh
4079 - CONFIG_SYS_DER: Debug Event Register (37-47)
4081 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
4082 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
4083 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
4084 CONFIG_SYS_BR1_PRELIM:
4085 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
4087 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
4088 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
4089 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
4090 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
4092 - CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K,
4093 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL:
4094 Machine Mode Register and Memory Periodic Timer
4095 Prescaler definitions (SDRAM timing)
4097 - CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]:
4098 enable I2C microcode relocation patch (MPC8xx);
4099 define relocation offset in DPRAM [DSP2]
4101 - CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]:
4102 enable SMC microcode relocation patch (MPC8xx);
4103 define relocation offset in DPRAM [SMC1]
4105 - CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]:
4106 enable SPI microcode relocation patch (MPC8xx);
4107 define relocation offset in DPRAM [SCC4]
4109 - CONFIG_SYS_USE_OSCCLK:
4110 Use OSCM clock mode on MBX8xx board. Be careful,
4111 wrong setting might damage your board. Read
4112 doc/README.MBX before setting this variable!
4114 - CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
4115 Offset of the bootmode word in DPRAM used by post
4116 (Power On Self Tests). This definition overrides
4117 #define'd default value in commproc.h resp.
4120 - CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB,
4121 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL,
4122 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS,
4123 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB,
4124 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
4125 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL,
4126 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE,
4127 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only)
4128 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set.
4130 - CONFIG_PCI_DISABLE_PCIE:
4131 Disable PCI-Express on systems where it is supported but not
4134 - CONFIG_PCI_ENUM_ONLY
4135 Only scan through and get the devices on the busses.
4136 Don't do any setup work, presumably because someone or
4137 something has already done it, and we don't need to do it
4138 a second time. Useful for platforms that are pre-booted
4139 by coreboot or similar.
4141 - CONFIG_PCI_INDIRECT_BRIDGE:
4142 Enable support for indirect PCI bridges.
4145 Chip has SRIO or not
4148 Board has SRIO 1 port available
4151 Board has SRIO 2 port available
4153 - CONFIG_SRIO_PCIE_BOOT_MASTER
4154 Board can support master function for Boot from SRIO and PCIE
4156 - CONFIG_SYS_SRIOn_MEM_VIRT:
4157 Virtual Address of SRIO port 'n' memory region
4159 - CONFIG_SYS_SRIOn_MEM_PHYS:
4160 Physical Address of SRIO port 'n' memory region
4162 - CONFIG_SYS_SRIOn_MEM_SIZE:
4163 Size of SRIO port 'n' memory region
4165 - CONFIG_SYS_NAND_BUSWIDTH_16BIT
4166 Defined to tell the NAND controller that the NAND chip is using
4168 Not all NAND drivers use this symbol.
4169 Example of drivers that use it:
4170 - drivers/mtd/nand/ndfc.c
4171 - drivers/mtd/nand/mxc_nand.c
4173 - CONFIG_SYS_NDFC_EBC0_CFG
4174 Sets the EBC0_CFG register for the NDFC. If not defined
4175 a default value will be used.
4178 Get DDR timing information from an I2C EEPROM. Common
4179 with pluggable memory modules such as SODIMMs
4182 I2C address of the SPD EEPROM
4184 - CONFIG_SYS_SPD_BUS_NUM
4185 If SPD EEPROM is on an I2C bus other than the first
4186 one, specify here. Note that the value must resolve
4187 to something your driver can deal with.
4189 - CONFIG_SYS_DDR_RAW_TIMING
4190 Get DDR timing information from other than SPD. Common with
4191 soldered DDR chips onboard without SPD. DDR raw timing
4192 parameters are extracted from datasheet and hard-coded into
4193 header files or board specific files.
4195 - CONFIG_FSL_DDR_INTERACTIVE
4196 Enable interactive DDR debugging. See doc/README.fsl-ddr.
4198 - CONFIG_SYS_83XX_DDR_USES_CS0
4199 Only for 83xx systems. If specified, then DDR should
4200 be configured using CS0 and CS1 instead of CS2 and CS3.
4202 - CONFIG_ETHER_ON_FEC[12]
4203 Define to enable FEC[12] on a 8xx series processor.
4205 - CONFIG_FEC[12]_PHY
4206 Define to the hardcoded PHY address which corresponds
4207 to the given FEC; i. e.
4208 #define CONFIG_FEC1_PHY 4
4209 means that the PHY with address 4 is connected to FEC1
4211 When set to -1, means to probe for first available.
4213 - CONFIG_FEC[12]_PHY_NORXERR
4214 The PHY does not have a RXERR line (RMII only).
4215 (so program the FEC to ignore it).
4218 Enable RMII mode for all FECs.
4219 Note that this is a global option, we can't
4220 have one FEC in standard MII mode and another in RMII mode.
4222 - CONFIG_CRC32_VERIFY
4223 Add a verify option to the crc32 command.
4226 => crc32 -v <address> <count> <crc32>
4228 Where address/count indicate a memory area
4229 and crc32 is the correct crc32 which the
4233 Add the "loopw" memory command. This only takes effect if
4234 the memory commands are activated globally (CONFIG_CMD_MEM).
4237 Add the "mdc" and "mwc" memory commands. These are cyclic
4242 This command will print 4 bytes (10,11,12,13) each 500 ms.
4244 => mwc.l 100 12345678 10
4245 This command will write 12345678 to address 100 all 10 ms.
4247 This only takes effect if the memory commands are activated
4248 globally (CONFIG_CMD_MEM).
4250 - CONFIG_SKIP_LOWLEVEL_INIT
4251 [ARM, NDS32, MIPS only] If this variable is defined, then certain
4252 low level initializations (like setting up the memory
4253 controller) are omitted and/or U-Boot does not
4254 relocate itself into RAM.
4256 Normally this variable MUST NOT be defined. The only
4257 exception is when U-Boot is loaded (to RAM) by some
4258 other boot loader or by a debugger which performs
4259 these initializations itself.
4262 Modifies the behaviour of start.S when compiling a loader
4263 that is executed before the actual U-Boot. E.g. when
4264 compiling a NAND SPL.
4267 Modifies the behaviour of start.S when compiling a loader
4268 that is executed after the SPL and before the actual U-Boot.
4269 It is loaded by the SPL.
4271 - CONFIG_SYS_MPC85XX_NO_RESETVEC
4272 Only for 85xx systems. If this variable is specified, the section
4273 .resetvec is not kept and the section .bootpg is placed in the
4274 previous 4k of the .text section.
4276 - CONFIG_ARCH_MAP_SYSMEM
4277 Generally U-Boot (and in particular the md command) uses
4278 effective address. It is therefore not necessary to regard
4279 U-Boot address as virtual addresses that need to be translated
4280 to physical addresses. However, sandbox requires this, since
4281 it maintains its own little RAM buffer which contains all
4282 addressable memory. This option causes some memory accesses
4283 to be mapped through map_sysmem() / unmap_sysmem().
4285 - CONFIG_USE_ARCH_MEMCPY
4286 CONFIG_USE_ARCH_MEMSET
4287 If these options are used a optimized version of memcpy/memset will
4288 be used if available. These functions may be faster under some
4289 conditions but may increase the binary size.
4291 - CONFIG_X86_RESET_VECTOR
4292 If defined, the x86 reset vector code is included. This is not
4293 needed when U-Boot is running from Coreboot.
4296 Defines the MPU clock speed (in MHz).
4298 NOTE : currently only supported on AM335x platforms.
4300 Freescale QE/FMAN Firmware Support:
4301 -----------------------------------
4303 The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
4304 loading of "firmware", which is encoded in the QE firmware binary format.
4305 This firmware often needs to be loaded during U-Boot booting, so macros
4306 are used to identify the storage device (NOR flash, SPI, etc) and the address
4309 - CONFIG_SYS_QE_FMAN_FW_ADDR
4310 The address in the storage device where the firmware is located. The
4311 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
4314 - CONFIG_SYS_QE_FMAN_FW_LENGTH
4315 The maximum possible size of the firmware. The firmware binary format
4316 has a field that specifies the actual size of the firmware, but it
4317 might not be possible to read any part of the firmware unless some
4318 local storage is allocated to hold the entire firmware first.
4320 - CONFIG_SYS_QE_FMAN_FW_IN_NOR
4321 Specifies that QE/FMAN firmware is located in NOR flash, mapped as
4322 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the
4323 virtual address in NOR flash.
4325 - CONFIG_SYS_QE_FMAN_FW_IN_NAND
4326 Specifies that QE/FMAN firmware is located in NAND flash.
4327 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.
4329 - CONFIG_SYS_QE_FMAN_FW_IN_MMC
4330 Specifies that QE/FMAN firmware is located on the primary SD/MMC
4331 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
4333 - CONFIG_SYS_QE_FMAN_FW_IN_SPIFLASH
4334 Specifies that QE/FMAN firmware is located on the primary SPI
4335 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
4337 - CONFIG_SYS_QE_FMAN_FW_IN_REMOTE
4338 Specifies that QE/FMAN firmware is located in the remote (master)
4339 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which
4340 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound
4341 window->master inbound window->master LAW->the ucode address in
4342 master's memory space.
4344 Building the Software:
4345 ======================
4347 Building U-Boot has been tested in several native build environments
4348 and in many different cross environments. Of course we cannot support
4349 all possibly existing versions of cross development tools in all
4350 (potentially obsolete) versions. In case of tool chain problems we
4351 recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
4352 which is extensively used to build and test U-Boot.
4354 If you are not using a native environment, it is assumed that you
4355 have GNU cross compiling tools available in your path. In this case,
4356 you must set the environment variable CROSS_COMPILE in your shell.
4357 Note that no changes to the Makefile or any other source files are
4358 necessary. For example using the ELDK on a 4xx CPU, please enter:
4360 $ CROSS_COMPILE=ppc_4xx-
4361 $ export CROSS_COMPILE
4363 Note: If you wish to generate Windows versions of the utilities in
4364 the tools directory you can use the MinGW toolchain
4365 (http://www.mingw.org). Set your HOST tools to the MinGW
4366 toolchain and execute 'make tools'. For example:
4368 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
4370 Binaries such as tools/mkimage.exe will be created which can
4371 be executed on computers running Windows.
4373 U-Boot is intended to be simple to build. After installing the
4374 sources you must configure U-Boot for one specific board type. This
4379 where "NAME_config" is the name of one of the existing configu-
4380 rations; see boards.cfg for supported names.
4382 Note: for some board special configuration names may exist; check if
4383 additional information is available from the board vendor; for
4384 instance, the TQM823L systems are available without (standard)
4385 or with LCD support. You can select such additional "features"
4386 when choosing the configuration, i. e.
4389 - will configure for a plain TQM823L, i. e. no LCD support
4391 make TQM823L_LCD_config
4392 - will configure for a TQM823L with U-Boot console on LCD
4397 Finally, type "make all", and you should get some working U-Boot
4398 images ready for download to / installation on your system:
4400 - "u-boot.bin" is a raw binary image
4401 - "u-boot" is an image in ELF binary format
4402 - "u-boot.srec" is in Motorola S-Record format
4404 By default the build is performed locally and the objects are saved
4405 in the source directory. One of the two methods can be used to change
4406 this behavior and build U-Boot to some external directory:
4408 1. Add O= to the make command line invocations:
4410 make O=/tmp/build distclean
4411 make O=/tmp/build NAME_config
4412 make O=/tmp/build all
4414 2. Set environment variable BUILD_DIR to point to the desired location:
4416 export BUILD_DIR=/tmp/build
4421 Note that the command line "O=" setting overrides the BUILD_DIR environment
4425 Please be aware that the Makefiles assume you are using GNU make, so
4426 for instance on NetBSD you might need to use "gmake" instead of
4430 If the system board that you have is not listed, then you will need
4431 to port U-Boot to your hardware platform. To do this, follow these
4434 1. Add a new configuration option for your board to the toplevel
4435 "boards.cfg" file, using the existing entries as examples.
4436 Follow the instructions there to keep the boards in order.
4437 2. Create a new directory to hold your board specific code. Add any
4438 files you need. In your board directory, you will need at least
4439 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
4440 3. Create a new configuration file "include/configs/<board>.h" for
4442 3. If you're porting U-Boot to a new CPU, then also create a new
4443 directory to hold your CPU specific code. Add any files you need.
4444 4. Run "make <board>_config" with your new name.
4445 5. Type "make", and you should get a working "u-boot.srec" file
4446 to be installed on your target system.
4447 6. Debug and solve any problems that might arise.
4448 [Of course, this last step is much harder than it sounds.]
4451 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
4452 ==============================================================
4454 If you have modified U-Boot sources (for instance added a new board
4455 or support for new devices, a new CPU, etc.) you are expected to
4456 provide feedback to the other developers. The feedback normally takes
4457 the form of a "patch", i. e. a context diff against a certain (latest
4458 official or latest in the git repository) version of U-Boot sources.
4460 But before you submit such a patch, please verify that your modifi-
4461 cation did not break existing code. At least make sure that *ALL* of
4462 the supported boards compile WITHOUT ANY compiler warnings. To do so,
4463 just run the "MAKEALL" script, which will configure and build U-Boot
4464 for ALL supported system. Be warned, this will take a while. You can
4465 select which (cross) compiler to use by passing a `CROSS_COMPILE'
4466 environment variable to the script, i. e. to use the ELDK cross tools
4469 CROSS_COMPILE=ppc_8xx- MAKEALL
4471 or to build on a native PowerPC system you can type
4473 CROSS_COMPILE=' ' MAKEALL
4475 When using the MAKEALL script, the default behaviour is to build
4476 U-Boot in the source directory. This location can be changed by
4477 setting the BUILD_DIR environment variable. Also, for each target
4478 built, the MAKEALL script saves two log files (<target>.ERR and
4479 <target>.MAKEALL) in the <source dir>/LOG directory. This default
4480 location can be changed by setting the MAKEALL_LOGDIR environment
4481 variable. For example:
4483 export BUILD_DIR=/tmp/build
4484 export MAKEALL_LOGDIR=/tmp/log
4485 CROSS_COMPILE=ppc_8xx- MAKEALL
4487 With the above settings build objects are saved in the /tmp/build,
4488 log files are saved in the /tmp/log and the source tree remains clean
4489 during the whole build process.
4492 See also "U-Boot Porting Guide" below.
4495 Monitor Commands - Overview:
4496 ============================
4498 go - start application at address 'addr'
4499 run - run commands in an environment variable
4500 bootm - boot application image from memory
4501 bootp - boot image via network using BootP/TFTP protocol
4502 bootz - boot zImage from memory
4503 tftpboot- boot image via network using TFTP protocol
4504 and env variables "ipaddr" and "serverip"
4505 (and eventually "gatewayip")
4506 tftpput - upload a file via network using TFTP protocol
4507 rarpboot- boot image via network using RARP/TFTP protocol
4508 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
4509 loads - load S-Record file over serial line
4510 loadb - load binary file over serial line (kermit mode)
4512 mm - memory modify (auto-incrementing)
4513 nm - memory modify (constant address)
4514 mw - memory write (fill)
4516 cmp - memory compare
4517 crc32 - checksum calculation
4518 i2c - I2C sub-system
4519 sspi - SPI utility commands
4520 base - print or set address offset
4521 printenv- print environment variables
4522 setenv - set environment variables
4523 saveenv - save environment variables to persistent storage
4524 protect - enable or disable FLASH write protection
4525 erase - erase FLASH memory
4526 flinfo - print FLASH memory information
4527 nand - NAND memory operations (see doc/README.nand)
4528 bdinfo - print Board Info structure
4529 iminfo - print header information for application image
4530 coninfo - print console devices and informations
4531 ide - IDE sub-system
4532 loop - infinite loop on address range
4533 loopw - infinite write loop on address range
4534 mtest - simple RAM test
4535 icache - enable or disable instruction cache
4536 dcache - enable or disable data cache
4537 reset - Perform RESET of the CPU
4538 echo - echo args to console
4539 version - print monitor version
4540 help - print online help
4541 ? - alias for 'help'
4544 Monitor Commands - Detailed Description:
4545 ========================================
4549 For now: just type "help <command>".
4552 Environment Variables:
4553 ======================
4555 U-Boot supports user configuration using Environment Variables which
4556 can be made persistent by saving to Flash memory.
4558 Environment Variables are set using "setenv", printed using
4559 "printenv", and saved to Flash using "saveenv". Using "setenv"
4560 without a value can be used to delete a variable from the
4561 environment. As long as you don't save the environment you are
4562 working with an in-memory copy. In case the Flash area containing the
4563 environment is erased by accident, a default environment is provided.
4565 Some configuration options can be set using Environment Variables.
4567 List of environment variables (most likely not complete):
4569 baudrate - see CONFIG_BAUDRATE
4571 bootdelay - see CONFIG_BOOTDELAY
4573 bootcmd - see CONFIG_BOOTCOMMAND
4575 bootargs - Boot arguments when booting an RTOS image
4577 bootfile - Name of the image to load with TFTP
4579 bootm_low - Memory range available for image processing in the bootm
4580 command can be restricted. This variable is given as
4581 a hexadecimal number and defines lowest address allowed
4582 for use by the bootm command. See also "bootm_size"
4583 environment variable. Address defined by "bootm_low" is
4584 also the base of the initial memory mapping for the Linux
4585 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
4588 bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
4589 This variable is given as a hexadecimal number and it
4590 defines the size of the memory region starting at base
4591 address bootm_low that is accessible by the Linux kernel
4592 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used
4593 as the default value if it is defined, and bootm_size is
4596 bootm_size - Memory range available for image processing in the bootm
4597 command can be restricted. This variable is given as
4598 a hexadecimal number and defines the size of the region
4599 allowed for use by the bootm command. See also "bootm_low"
4600 environment variable.
4602 updatefile - Location of the software update file on a TFTP server, used
4603 by the automatic software update feature. Please refer to
4604 documentation in doc/README.update for more details.
4606 autoload - if set to "no" (any string beginning with 'n'),
4607 "bootp" will just load perform a lookup of the
4608 configuration from the BOOTP server, but not try to
4609 load any image using TFTP
4611 autostart - if set to "yes", an image loaded using the "bootp",
4612 "rarpboot", "tftpboot" or "diskboot" commands will
4613 be automatically started (by internally calling
4616 If set to "no", a standalone image passed to the
4617 "bootm" command will be copied to the load address
4618 (and eventually uncompressed), but NOT be started.
4619 This can be used to load and uncompress arbitrary
4622 fdt_high - if set this restricts the maximum address that the
4623 flattened device tree will be copied into upon boot.
4624 For example, if you have a system with 1 GB memory
4625 at physical address 0x10000000, while Linux kernel
4626 only recognizes the first 704 MB as low memory, you
4627 may need to set fdt_high as 0x3C000000 to have the
4628 device tree blob be copied to the maximum address
4629 of the 704 MB low memory, so that Linux kernel can
4630 access it during the boot procedure.
4632 If this is set to the special value 0xFFFFFFFF then
4633 the fdt will not be copied at all on boot. For this
4634 to work it must reside in writable memory, have
4635 sufficient padding on the end of it for u-boot to
4636 add the information it needs into it, and the memory
4637 must be accessible by the kernel.
4639 fdtcontroladdr- if set this is the address of the control flattened
4640 device tree used by U-Boot when CONFIG_OF_CONTROL is
4643 i2cfast - (PPC405GP|PPC405EP only)
4644 if set to 'y' configures Linux I2C driver for fast
4645 mode (400kHZ). This environment variable is used in
4646 initialization code. So, for changes to be effective
4647 it must be saved and board must be reset.
4649 initrd_high - restrict positioning of initrd images:
4650 If this variable is not set, initrd images will be
4651 copied to the highest possible address in RAM; this
4652 is usually what you want since it allows for
4653 maximum initrd size. If for some reason you want to
4654 make sure that the initrd image is loaded below the
4655 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
4656 variable to a value of "no" or "off" or "0".
4657 Alternatively, you can set it to a maximum upper
4658 address to use (U-Boot will still check that it
4659 does not overwrite the U-Boot stack and data).
4661 For instance, when you have a system with 16 MB
4662 RAM, and want to reserve 4 MB from use by Linux,
4663 you can do this by adding "mem=12M" to the value of
4664 the "bootargs" variable. However, now you must make
4665 sure that the initrd image is placed in the first
4666 12 MB as well - this can be done with
4668 setenv initrd_high 00c00000
4670 If you set initrd_high to 0xFFFFFFFF, this is an
4671 indication to U-Boot that all addresses are legal
4672 for the Linux kernel, including addresses in flash
4673 memory. In this case U-Boot will NOT COPY the
4674 ramdisk at all. This may be useful to reduce the
4675 boot time on your system, but requires that this
4676 feature is supported by your Linux kernel.
4678 ipaddr - IP address; needed for tftpboot command
4680 loadaddr - Default load address for commands like "bootp",
4681 "rarpboot", "tftpboot", "loadb" or "diskboot"
4683 loads_echo - see CONFIG_LOADS_ECHO
4685 serverip - TFTP server IP address; needed for tftpboot command
4687 bootretry - see CONFIG_BOOT_RETRY_TIME
4689 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
4691 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
4693 ethprime - controls which interface is used first.
4695 ethact - controls which interface is currently active.
4696 For example you can do the following
4698 => setenv ethact FEC
4699 => ping 192.168.0.1 # traffic sent on FEC
4700 => setenv ethact SCC
4701 => ping 10.0.0.1 # traffic sent on SCC
4703 ethrotate - When set to "no" U-Boot does not go through all
4704 available network interfaces.
4705 It just stays at the currently selected interface.
4707 netretry - When set to "no" each network operation will
4708 either succeed or fail without retrying.
4709 When set to "once" the network operation will
4710 fail when all the available network interfaces
4711 are tried once without success.
4712 Useful on scripts which control the retry operation
4715 npe_ucode - set load address for the NPE microcode
4717 silent_linux - If set then linux will be told to boot silently, by
4718 changing the console to be empty. If "yes" it will be
4719 made silent. If "no" it will not be made silent. If
4720 unset, then it will be made silent if the U-Boot console
4723 tftpsrcport - If this is set, the value is used for TFTP's
4726 tftpdstport - If this is set, the value is used for TFTP's UDP
4727 destination port instead of the Well Know Port 69.
4729 tftpblocksize - Block size to use for TFTP transfers; if not set,
4730 we use the TFTP server's default block size
4732 tftptimeout - Retransmission timeout for TFTP packets (in milli-
4733 seconds, minimum value is 1000 = 1 second). Defines
4734 when a packet is considered to be lost so it has to
4735 be retransmitted. The default is 5000 = 5 seconds.
4736 Lowering this value may make downloads succeed
4737 faster in networks with high packet loss rates or
4738 with unreliable TFTP servers.
4740 vlan - When set to a value < 4095 the traffic over
4741 Ethernet is encapsulated/received over 802.1q
4744 The following image location variables contain the location of images
4745 used in booting. The "Image" column gives the role of the image and is
4746 not an environment variable name. The other columns are environment
4747 variable names. "File Name" gives the name of the file on a TFTP
4748 server, "RAM Address" gives the location in RAM the image will be
4749 loaded to, and "Flash Location" gives the image's address in NOR
4750 flash or offset in NAND flash.
4752 *Note* - these variables don't have to be defined for all boards, some
4753 boards currenlty use other variables for these purposes, and some
4754 boards use these variables for other purposes.
4756 Image File Name RAM Address Flash Location
4757 ----- --------- ----------- --------------
4758 u-boot u-boot u-boot_addr_r u-boot_addr
4759 Linux kernel bootfile kernel_addr_r kernel_addr
4760 device tree blob fdtfile fdt_addr_r fdt_addr
4761 ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr
4763 The following environment variables may be used and automatically
4764 updated by the network boot commands ("bootp" and "rarpboot"),
4765 depending the information provided by your boot server:
4767 bootfile - see above
4768 dnsip - IP address of your Domain Name Server
4769 dnsip2 - IP address of your secondary Domain Name Server
4770 gatewayip - IP address of the Gateway (Router) to use
4771 hostname - Target hostname
4773 netmask - Subnet Mask
4774 rootpath - Pathname of the root filesystem on the NFS server
4775 serverip - see above
4778 There are two special Environment Variables:
4780 serial# - contains hardware identification information such
4781 as type string and/or serial number
4782 ethaddr - Ethernet address
4784 These variables can be set only once (usually during manufacturing of
4785 the board). U-Boot refuses to delete or overwrite these variables
4786 once they have been set once.
4789 Further special Environment Variables:
4791 ver - Contains the U-Boot version string as printed
4792 with the "version" command. This variable is
4793 readonly (see CONFIG_VERSION_VARIABLE).
4796 Please note that changes to some configuration parameters may take
4797 only effect after the next boot (yes, that's just like Windoze :-).
4800 Callback functions for environment variables:
4801 ---------------------------------------------
4803 For some environment variables, the behavior of u-boot needs to change
4804 when their values are changed. This functionailty allows functions to
4805 be associated with arbitrary variables. On creation, overwrite, or
4806 deletion, the callback will provide the opportunity for some side
4807 effect to happen or for the change to be rejected.
4809 The callbacks are named and associated with a function using the
4810 U_BOOT_ENV_CALLBACK macro in your board or driver code.
4812 These callbacks are associated with variables in one of two ways. The
4813 static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC
4814 in the board configuration to a string that defines a list of
4815 associations. The list must be in the following format:
4817 entry = variable_name[:callback_name]
4820 If the callback name is not specified, then the callback is deleted.
4821 Spaces are also allowed anywhere in the list.
4823 Callbacks can also be associated by defining the ".callbacks" variable
4824 with the same list format above. Any association in ".callbacks" will
4825 override any association in the static list. You can define
4826 CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the
4827 ".callbacks" envirnoment variable in the default or embedded environment.
4830 Command Line Parsing:
4831 =====================
4833 There are two different command line parsers available with U-Boot:
4834 the old "simple" one, and the much more powerful "hush" shell:
4836 Old, simple command line parser:
4837 --------------------------------
4839 - supports environment variables (through setenv / saveenv commands)
4840 - several commands on one line, separated by ';'
4841 - variable substitution using "... ${name} ..." syntax
4842 - special characters ('$', ';') can be escaped by prefixing with '\',
4844 setenv bootcmd bootm \${address}
4845 - You can also escape text by enclosing in single apostrophes, for example:
4846 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
4851 - similar to Bourne shell, with control structures like
4852 if...then...else...fi, for...do...done; while...do...done,
4853 until...do...done, ...
4854 - supports environment ("global") variables (through setenv / saveenv
4855 commands) and local shell variables (through standard shell syntax
4856 "name=value"); only environment variables can be used with "run"
4862 (1) If a command line (or an environment variable executed by a "run"
4863 command) contains several commands separated by semicolon, and
4864 one of these commands fails, then the remaining commands will be
4867 (2) If you execute several variables with one call to run (i. e.
4868 calling run with a list of variables as arguments), any failing
4869 command will cause "run" to terminate, i. e. the remaining
4870 variables are not executed.
4872 Note for Redundant Ethernet Interfaces:
4873 =======================================
4875 Some boards come with redundant Ethernet interfaces; U-Boot supports
4876 such configurations and is capable of automatic selection of a
4877 "working" interface when needed. MAC assignment works as follows:
4879 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
4880 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
4881 "eth1addr" (=>eth1), "eth2addr", ...
4883 If the network interface stores some valid MAC address (for instance
4884 in SROM), this is used as default address if there is NO correspon-
4885 ding setting in the environment; if the corresponding environment
4886 variable is set, this overrides the settings in the card; that means:
4888 o If the SROM has a valid MAC address, and there is no address in the
4889 environment, the SROM's address is used.
4891 o If there is no valid address in the SROM, and a definition in the
4892 environment exists, then the value from the environment variable is
4895 o If both the SROM and the environment contain a MAC address, and
4896 both addresses are the same, this MAC address is used.
4898 o If both the SROM and the environment contain a MAC address, and the
4899 addresses differ, the value from the environment is used and a
4902 o If neither SROM nor the environment contain a MAC address, an error
4905 If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
4906 will be programmed into hardware as part of the initialization process. This
4907 may be skipped by setting the appropriate 'ethmacskip' environment variable.
4908 The naming convention is as follows:
4909 "ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
4914 U-Boot is capable of booting (and performing other auxiliary operations on)
4915 images in two formats:
4917 New uImage format (FIT)
4918 -----------------------
4920 Flexible and powerful format based on Flattened Image Tree -- FIT (similar
4921 to Flattened Device Tree). It allows the use of images with multiple
4922 components (several kernels, ramdisks, etc.), with contents protected by
4923 SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
4929 Old image format is based on binary files which can be basically anything,
4930 preceded by a special header; see the definitions in include/image.h for
4931 details; basically, the header defines the following image properties:
4933 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
4934 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
4935 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
4936 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
4938 * Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86,
4939 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
4940 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC).
4941 * Compression Type (uncompressed, gzip, bzip2)
4947 The header is marked by a special Magic Number, and both the header
4948 and the data portions of the image are secured against corruption by
4955 Although U-Boot should support any OS or standalone application
4956 easily, the main focus has always been on Linux during the design of
4959 U-Boot includes many features that so far have been part of some
4960 special "boot loader" code within the Linux kernel. Also, any
4961 "initrd" images to be used are no longer part of one big Linux image;
4962 instead, kernel and "initrd" are separate images. This implementation
4963 serves several purposes:
4965 - the same features can be used for other OS or standalone
4966 applications (for instance: using compressed images to reduce the
4967 Flash memory footprint)
4969 - it becomes much easier to port new Linux kernel versions because
4970 lots of low-level, hardware dependent stuff are done by U-Boot
4972 - the same Linux kernel image can now be used with different "initrd"
4973 images; of course this also means that different kernel images can
4974 be run with the same "initrd". This makes testing easier (you don't
4975 have to build a new "zImage.initrd" Linux image when you just
4976 change a file in your "initrd"). Also, a field-upgrade of the
4977 software is easier now.
4983 Porting Linux to U-Boot based systems:
4984 ---------------------------------------
4986 U-Boot cannot save you from doing all the necessary modifications to
4987 configure the Linux device drivers for use with your target hardware
4988 (no, we don't intend to provide a full virtual machine interface to
4991 But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
4993 Just make sure your machine specific header file (for instance
4994 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
4995 Information structure as we define in include/asm-<arch>/u-boot.h,
4996 and make sure that your definition of IMAP_ADDR uses the same value
4997 as your U-Boot configuration in CONFIG_SYS_IMMR.
5000 Configuring the Linux kernel:
5001 -----------------------------
5003 No specific requirements for U-Boot. Make sure you have some root
5004 device (initial ramdisk, NFS) for your target system.
5007 Building a Linux Image:
5008 -----------------------
5010 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
5011 not used. If you use recent kernel source, a new build target
5012 "uImage" will exist which automatically builds an image usable by
5013 U-Boot. Most older kernels also have support for a "pImage" target,
5014 which was introduced for our predecessor project PPCBoot and uses a
5015 100% compatible format.
5024 The "uImage" build target uses a special tool (in 'tools/mkimage') to
5025 encapsulate a compressed Linux kernel image with header information,
5026 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
5028 * build a standard "vmlinux" kernel image (in ELF binary format):
5030 * convert the kernel into a raw binary image:
5032 ${CROSS_COMPILE}-objcopy -O binary \
5033 -R .note -R .comment \
5034 -S vmlinux linux.bin
5036 * compress the binary image:
5040 * package compressed binary image for U-Boot:
5042 mkimage -A ppc -O linux -T kernel -C gzip \
5043 -a 0 -e 0 -n "Linux Kernel Image" \
5044 -d linux.bin.gz uImage
5047 The "mkimage" tool can also be used to create ramdisk images for use
5048 with U-Boot, either separated from the Linux kernel image, or
5049 combined into one file. "mkimage" encapsulates the images with a 64
5050 byte header containing information about target architecture,
5051 operating system, image type, compression method, entry points, time
5052 stamp, CRC32 checksums, etc.
5054 "mkimage" can be called in two ways: to verify existing images and
5055 print the header information, or to build new images.
5057 In the first form (with "-l" option) mkimage lists the information
5058 contained in the header of an existing U-Boot image; this includes
5059 checksum verification:
5061 tools/mkimage -l image
5062 -l ==> list image header information
5064 The second form (with "-d" option) is used to build a U-Boot image
5065 from a "data file" which is used as image payload:
5067 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
5068 -n name -d data_file image
5069 -A ==> set architecture to 'arch'
5070 -O ==> set operating system to 'os'
5071 -T ==> set image type to 'type'
5072 -C ==> set compression type 'comp'
5073 -a ==> set load address to 'addr' (hex)
5074 -e ==> set entry point to 'ep' (hex)
5075 -n ==> set image name to 'name'
5076 -d ==> use image data from 'datafile'
5078 Right now, all Linux kernels for PowerPC systems use the same load
5079 address (0x00000000), but the entry point address depends on the
5082 - 2.2.x kernels have the entry point at 0x0000000C,
5083 - 2.3.x and later kernels have the entry point at 0x00000000.
5085 So a typical call to build a U-Boot image would read:
5087 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
5088 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
5089 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
5090 > examples/uImage.TQM850L
5091 Image Name: 2.4.4 kernel for TQM850L
5092 Created: Wed Jul 19 02:34:59 2000
5093 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5094 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
5095 Load Address: 0x00000000
5096 Entry Point: 0x00000000
5098 To verify the contents of the image (or check for corruption):
5100 -> tools/mkimage -l examples/uImage.TQM850L
5101 Image Name: 2.4.4 kernel for TQM850L
5102 Created: Wed Jul 19 02:34:59 2000
5103 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5104 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
5105 Load Address: 0x00000000
5106 Entry Point: 0x00000000
5108 NOTE: for embedded systems where boot time is critical you can trade
5109 speed for memory and install an UNCOMPRESSED image instead: this
5110 needs more space in Flash, but boots much faster since it does not
5111 need to be uncompressed:
5113 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
5114 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
5115 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
5116 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
5117 > examples/uImage.TQM850L-uncompressed
5118 Image Name: 2.4.4 kernel for TQM850L
5119 Created: Wed Jul 19 02:34:59 2000
5120 Image Type: PowerPC Linux Kernel Image (uncompressed)
5121 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
5122 Load Address: 0x00000000
5123 Entry Point: 0x00000000
5126 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
5127 when your kernel is intended to use an initial ramdisk:
5129 -> tools/mkimage -n 'Simple Ramdisk Image' \
5130 > -A ppc -O linux -T ramdisk -C gzip \
5131 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
5132 Image Name: Simple Ramdisk Image
5133 Created: Wed Jan 12 14:01:50 2000
5134 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5135 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
5136 Load Address: 0x00000000
5137 Entry Point: 0x00000000
5140 Installing a Linux Image:
5141 -------------------------
5143 To downloading a U-Boot image over the serial (console) interface,
5144 you must convert the image to S-Record format:
5146 objcopy -I binary -O srec examples/image examples/image.srec
5148 The 'objcopy' does not understand the information in the U-Boot
5149 image header, so the resulting S-Record file will be relative to
5150 address 0x00000000. To load it to a given address, you need to
5151 specify the target address as 'offset' parameter with the 'loads'
5154 Example: install the image to address 0x40100000 (which on the
5155 TQM8xxL is in the first Flash bank):
5157 => erase 40100000 401FFFFF
5163 ## Ready for S-Record download ...
5164 ~>examples/image.srec
5165 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
5167 15989 15990 15991 15992
5168 [file transfer complete]
5170 ## Start Addr = 0x00000000
5173 You can check the success of the download using the 'iminfo' command;
5174 this includes a checksum verification so you can be sure no data
5175 corruption happened:
5179 ## Checking Image at 40100000 ...
5180 Image Name: 2.2.13 for initrd on TQM850L
5181 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5182 Data Size: 335725 Bytes = 327 kB = 0 MB
5183 Load Address: 00000000
5184 Entry Point: 0000000c
5185 Verifying Checksum ... OK
5191 The "bootm" command is used to boot an application that is stored in
5192 memory (RAM or Flash). In case of a Linux kernel image, the contents
5193 of the "bootargs" environment variable is passed to the kernel as
5194 parameters. You can check and modify this variable using the
5195 "printenv" and "setenv" commands:
5198 => printenv bootargs
5199 bootargs=root=/dev/ram
5201 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5203 => printenv bootargs
5204 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5207 ## Booting Linux kernel at 40020000 ...
5208 Image Name: 2.2.13 for NFS on TQM850L
5209 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5210 Data Size: 381681 Bytes = 372 kB = 0 MB
5211 Load Address: 00000000
5212 Entry Point: 0000000c
5213 Verifying Checksum ... OK
5214 Uncompressing Kernel Image ... OK
5215 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
5216 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5217 time_init: decrementer frequency = 187500000/60
5218 Calibrating delay loop... 49.77 BogoMIPS
5219 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
5222 If you want to boot a Linux kernel with initial RAM disk, you pass
5223 the memory addresses of both the kernel and the initrd image (PPBCOOT
5224 format!) to the "bootm" command:
5226 => imi 40100000 40200000
5228 ## Checking Image at 40100000 ...
5229 Image Name: 2.2.13 for initrd on TQM850L
5230 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5231 Data Size: 335725 Bytes = 327 kB = 0 MB
5232 Load Address: 00000000
5233 Entry Point: 0000000c
5234 Verifying Checksum ... OK
5236 ## Checking Image at 40200000 ...
5237 Image Name: Simple Ramdisk Image
5238 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5239 Data Size: 566530 Bytes = 553 kB = 0 MB
5240 Load Address: 00000000
5241 Entry Point: 00000000
5242 Verifying Checksum ... OK
5244 => bootm 40100000 40200000
5245 ## Booting Linux kernel at 40100000 ...
5246 Image Name: 2.2.13 for initrd on TQM850L
5247 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5248 Data Size: 335725 Bytes = 327 kB = 0 MB
5249 Load Address: 00000000
5250 Entry Point: 0000000c
5251 Verifying Checksum ... OK
5252 Uncompressing Kernel Image ... OK
5253 ## Loading RAMDisk Image at 40200000 ...
5254 Image Name: Simple Ramdisk Image
5255 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5256 Data Size: 566530 Bytes = 553 kB = 0 MB
5257 Load Address: 00000000
5258 Entry Point: 00000000
5259 Verifying Checksum ... OK
5260 Loading Ramdisk ... OK
5261 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
5262 Boot arguments: root=/dev/ram
5263 time_init: decrementer frequency = 187500000/60
5264 Calibrating delay loop... 49.77 BogoMIPS
5266 RAMDISK: Compressed image found at block 0
5267 VFS: Mounted root (ext2 filesystem).
5271 Boot Linux and pass a flat device tree:
5274 First, U-Boot must be compiled with the appropriate defines. See the section
5275 titled "Linux Kernel Interface" above for a more in depth explanation. The
5276 following is an example of how to start a kernel and pass an updated
5282 oft=oftrees/mpc8540ads.dtb
5283 => tftp $oftaddr $oft
5284 Speed: 1000, full duplex
5286 TFTP from server 192.168.1.1; our IP address is 192.168.1.101
5287 Filename 'oftrees/mpc8540ads.dtb'.
5288 Load address: 0x300000
5291 Bytes transferred = 4106 (100a hex)
5292 => tftp $loadaddr $bootfile
5293 Speed: 1000, full duplex
5295 TFTP from server 192.168.1.1; our IP address is 192.168.1.2
5297 Load address: 0x200000
5298 Loading:############
5300 Bytes transferred = 1029407 (fb51f hex)
5305 => bootm $loadaddr - $oftaddr
5306 ## Booting image at 00200000 ...
5307 Image Name: Linux-2.6.17-dirty
5308 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5309 Data Size: 1029343 Bytes = 1005.2 kB
5310 Load Address: 00000000
5311 Entry Point: 00000000
5312 Verifying Checksum ... OK
5313 Uncompressing Kernel Image ... OK
5314 Booting using flat device tree at 0x300000
5315 Using MPC85xx ADS machine description
5316 Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
5320 More About U-Boot Image Types:
5321 ------------------------------
5323 U-Boot supports the following image types:
5325 "Standalone Programs" are directly runnable in the environment
5326 provided by U-Boot; it is expected that (if they behave
5327 well) you can continue to work in U-Boot after return from
5328 the Standalone Program.
5329 "OS Kernel Images" are usually images of some Embedded OS which
5330 will take over control completely. Usually these programs
5331 will install their own set of exception handlers, device
5332 drivers, set up the MMU, etc. - this means, that you cannot
5333 expect to re-enter U-Boot except by resetting the CPU.
5334 "RAMDisk Images" are more or less just data blocks, and their
5335 parameters (address, size) are passed to an OS kernel that is
5337 "Multi-File Images" contain several images, typically an OS
5338 (Linux) kernel image and one or more data images like
5339 RAMDisks. This construct is useful for instance when you want
5340 to boot over the network using BOOTP etc., where the boot
5341 server provides just a single image file, but you want to get
5342 for instance an OS kernel and a RAMDisk image.
5344 "Multi-File Images" start with a list of image sizes, each
5345 image size (in bytes) specified by an "uint32_t" in network
5346 byte order. This list is terminated by an "(uint32_t)0".
5347 Immediately after the terminating 0 follow the images, one by
5348 one, all aligned on "uint32_t" boundaries (size rounded up to
5349 a multiple of 4 bytes).
5351 "Firmware Images" are binary images containing firmware (like
5352 U-Boot or FPGA images) which usually will be programmed to
5355 "Script files" are command sequences that will be executed by
5356 U-Boot's command interpreter; this feature is especially
5357 useful when you configure U-Boot to use a real shell (hush)
5358 as command interpreter.
5360 Booting the Linux zImage:
5361 -------------------------
5363 On some platforms, it's possible to boot Linux zImage. This is done
5364 using the "bootz" command. The syntax of "bootz" command is the same
5365 as the syntax of "bootm" command.
5367 Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply
5368 kernel with raw initrd images. The syntax is slightly different, the
5369 address of the initrd must be augmented by it's size, in the following
5370 format: "<initrd addres>:<initrd size>".
5376 One of the features of U-Boot is that you can dynamically load and
5377 run "standalone" applications, which can use some resources of
5378 U-Boot like console I/O functions or interrupt services.
5380 Two simple examples are included with the sources:
5385 'examples/hello_world.c' contains a small "Hello World" Demo
5386 application; it is automatically compiled when you build U-Boot.
5387 It's configured to run at address 0x00040004, so you can play with it
5391 ## Ready for S-Record download ...
5392 ~>examples/hello_world.srec
5393 1 2 3 4 5 6 7 8 9 10 11 ...
5394 [file transfer complete]
5396 ## Start Addr = 0x00040004
5398 => go 40004 Hello World! This is a test.
5399 ## Starting application at 0x00040004 ...
5410 Hit any key to exit ...
5412 ## Application terminated, rc = 0x0
5414 Another example, which demonstrates how to register a CPM interrupt
5415 handler with the U-Boot code, can be found in 'examples/timer.c'.
5416 Here, a CPM timer is set up to generate an interrupt every second.
5417 The interrupt service routine is trivial, just printing a '.'
5418 character, but this is just a demo program. The application can be
5419 controlled by the following keys:
5421 ? - print current values og the CPM Timer registers
5422 b - enable interrupts and start timer
5423 e - stop timer and disable interrupts
5424 q - quit application
5427 ## Ready for S-Record download ...
5428 ~>examples/timer.srec
5429 1 2 3 4 5 6 7 8 9 10 11 ...
5430 [file transfer complete]
5432 ## Start Addr = 0x00040004
5435 ## Starting application at 0x00040004 ...
5438 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
5441 [q, b, e, ?] Set interval 1000000 us
5444 [q, b, e, ?] ........
5445 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
5448 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
5451 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
5454 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
5456 [q, b, e, ?] ...Stopping timer
5458 [q, b, e, ?] ## Application terminated, rc = 0x0
5464 Over time, many people have reported problems when trying to use the
5465 "minicom" terminal emulation program for serial download. I (wd)
5466 consider minicom to be broken, and recommend not to use it. Under
5467 Unix, I recommend to use C-Kermit for general purpose use (and
5468 especially for kermit binary protocol download ("loadb" command), and
5469 use "cu" for S-Record download ("loads" command). See
5470 http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3.
5471 for help with kermit.
5474 Nevertheless, if you absolutely want to use it try adding this
5475 configuration to your "File transfer protocols" section:
5477 Name Program Name U/D FullScr IO-Red. Multi
5478 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
5479 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
5485 Starting at version 0.9.2, U-Boot supports NetBSD both as host
5486 (build U-Boot) and target system (boots NetBSD/mpc8xx).
5488 Building requires a cross environment; it is known to work on
5489 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
5490 need gmake since the Makefiles are not compatible with BSD make).
5491 Note that the cross-powerpc package does not install include files;
5492 attempting to build U-Boot will fail because <machine/ansi.h> is
5493 missing. This file has to be installed and patched manually:
5495 # cd /usr/pkg/cross/powerpc-netbsd/include
5497 # ln -s powerpc machine
5498 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
5499 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
5501 Native builds *don't* work due to incompatibilities between native
5502 and U-Boot include files.
5504 Booting assumes that (the first part of) the image booted is a
5505 stage-2 loader which in turn loads and then invokes the kernel
5506 proper. Loader sources will eventually appear in the NetBSD source
5507 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
5508 meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
5511 Implementation Internals:
5512 =========================
5514 The following is not intended to be a complete description of every
5515 implementation detail. However, it should help to understand the
5516 inner workings of U-Boot and make it easier to port it to custom
5520 Initial Stack, Global Data:
5521 ---------------------------
5523 The implementation of U-Boot is complicated by the fact that U-Boot
5524 starts running out of ROM (flash memory), usually without access to
5525 system RAM (because the memory controller is not initialized yet).
5526 This means that we don't have writable Data or BSS segments, and BSS
5527 is not initialized as zero. To be able to get a C environment working
5528 at all, we have to allocate at least a minimal stack. Implementation
5529 options for this are defined and restricted by the CPU used: Some CPU
5530 models provide on-chip memory (like the IMMR area on MPC8xx and
5531 MPC826x processors), on others (parts of) the data cache can be
5532 locked as (mis-) used as memory, etc.
5534 Chris Hallinan posted a good summary of these issues to the
5535 U-Boot mailing list:
5537 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
5538 From: "Chris Hallinan" <clh@net1plus.com>
5539 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
5542 Correct me if I'm wrong, folks, but the way I understand it
5543 is this: Using DCACHE as initial RAM for Stack, etc, does not
5544 require any physical RAM backing up the cache. The cleverness
5545 is that the cache is being used as a temporary supply of
5546 necessary storage before the SDRAM controller is setup. It's
5547 beyond the scope of this list to explain the details, but you
5548 can see how this works by studying the cache architecture and
5549 operation in the architecture and processor-specific manuals.
5551 OCM is On Chip Memory, which I believe the 405GP has 4K. It
5552 is another option for the system designer to use as an
5553 initial stack/RAM area prior to SDRAM being available. Either
5554 option should work for you. Using CS 4 should be fine if your
5555 board designers haven't used it for something that would
5556 cause you grief during the initial boot! It is frequently not
5559 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
5560 with your processor/board/system design. The default value
5561 you will find in any recent u-boot distribution in
5562 walnut.h should work for you. I'd set it to a value larger
5563 than your SDRAM module. If you have a 64MB SDRAM module, set
5564 it above 400_0000. Just make sure your board has no resources
5565 that are supposed to respond to that address! That code in
5566 start.S has been around a while and should work as is when
5567 you get the config right.
5572 It is essential to remember this, since it has some impact on the C
5573 code for the initialization procedures:
5575 * Initialized global data (data segment) is read-only. Do not attempt
5578 * Do not use any uninitialized global data (or implicitely initialized
5579 as zero data - BSS segment) at all - this is undefined, initiali-
5580 zation is performed later (when relocating to RAM).
5582 * Stack space is very limited. Avoid big data buffers or things like
5585 Having only the stack as writable memory limits means we cannot use
5586 normal global data to share information beween the code. But it
5587 turned out that the implementation of U-Boot can be greatly
5588 simplified by making a global data structure (gd_t) available to all
5589 functions. We could pass a pointer to this data as argument to _all_
5590 functions, but this would bloat the code. Instead we use a feature of
5591 the GCC compiler (Global Register Variables) to share the data: we
5592 place a pointer (gd) to the global data into a register which we
5593 reserve for this purpose.
5595 When choosing a register for such a purpose we are restricted by the
5596 relevant (E)ABI specifications for the current architecture, and by
5597 GCC's implementation.
5599 For PowerPC, the following registers have specific use:
5601 R2: reserved for system use
5602 R3-R4: parameter passing and return values
5603 R5-R10: parameter passing
5604 R13: small data area pointer
5608 (U-Boot also uses R12 as internal GOT pointer. r12
5609 is a volatile register so r12 needs to be reset when
5610 going back and forth between asm and C)
5612 ==> U-Boot will use R2 to hold a pointer to the global data
5614 Note: on PPC, we could use a static initializer (since the
5615 address of the global data structure is known at compile time),
5616 but it turned out that reserving a register results in somewhat
5617 smaller code - although the code savings are not that big (on
5618 average for all boards 752 bytes for the whole U-Boot image,
5619 624 text + 127 data).
5621 On Blackfin, the normal C ABI (except for P3) is followed as documented here:
5622 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface
5624 ==> U-Boot will use P3 to hold a pointer to the global data
5626 On ARM, the following registers are used:
5628 R0: function argument word/integer result
5629 R1-R3: function argument word
5630 R9: platform specific
5631 R10: stack limit (used only if stack checking is enabled)
5632 R11: argument (frame) pointer
5633 R12: temporary workspace
5636 R15: program counter
5638 ==> U-Boot will use R9 to hold a pointer to the global data
5640 Note: on ARM, only R_ARM_RELATIVE relocations are supported.
5642 On Nios II, the ABI is documented here:
5643 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
5645 ==> U-Boot will use gp to hold a pointer to the global data
5647 Note: on Nios II, we give "-G0" option to gcc and don't use gp
5648 to access small data sections, so gp is free.
5650 On NDS32, the following registers are used:
5652 R0-R1: argument/return
5654 R15: temporary register for assembler
5655 R16: trampoline register
5656 R28: frame pointer (FP)
5657 R29: global pointer (GP)
5658 R30: link register (LP)
5659 R31: stack pointer (SP)
5660 PC: program counter (PC)
5662 ==> U-Boot will use R10 to hold a pointer to the global data
5664 NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
5665 or current versions of GCC may "optimize" the code too much.
5670 U-Boot runs in system state and uses physical addresses, i.e. the
5671 MMU is not used either for address mapping nor for memory protection.
5673 The available memory is mapped to fixed addresses using the memory
5674 controller. In this process, a contiguous block is formed for each
5675 memory type (Flash, SDRAM, SRAM), even when it consists of several
5676 physical memory banks.
5678 U-Boot is installed in the first 128 kB of the first Flash bank (on
5679 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
5680 booting and sizing and initializing DRAM, the code relocates itself
5681 to the upper end of DRAM. Immediately below the U-Boot code some
5682 memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
5683 configuration setting]. Below that, a structure with global Board
5684 Info data is placed, followed by the stack (growing downward).
5686 Additionally, some exception handler code is copied to the low 8 kB
5687 of DRAM (0x00000000 ... 0x00001FFF).
5689 So a typical memory configuration with 16 MB of DRAM could look like
5692 0x0000 0000 Exception Vector code
5695 0x0000 2000 Free for Application Use
5701 0x00FB FF20 Monitor Stack (Growing downward)
5702 0x00FB FFAC Board Info Data and permanent copy of global data
5703 0x00FC 0000 Malloc Arena
5706 0x00FE 0000 RAM Copy of Monitor Code
5707 ... eventually: LCD or video framebuffer
5708 ... eventually: pRAM (Protected RAM - unchanged by reset)
5709 0x00FF FFFF [End of RAM]
5712 System Initialization:
5713 ----------------------
5715 In the reset configuration, U-Boot starts at the reset entry point
5716 (on most PowerPC systems at address 0x00000100). Because of the reset
5717 configuration for CS0# this is a mirror of the onboard Flash memory.
5718 To be able to re-map memory U-Boot then jumps to its link address.
5719 To be able to implement the initialization code in C, a (small!)
5720 initial stack is set up in the internal Dual Ported RAM (in case CPUs
5721 which provide such a feature like MPC8xx or MPC8260), or in a locked
5722 part of the data cache. After that, U-Boot initializes the CPU core,
5723 the caches and the SIU.
5725 Next, all (potentially) available memory banks are mapped using a
5726 preliminary mapping. For example, we put them on 512 MB boundaries
5727 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
5728 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
5729 programmed for SDRAM access. Using the temporary configuration, a
5730 simple memory test is run that determines the size of the SDRAM
5733 When there is more than one SDRAM bank, and the banks are of
5734 different size, the largest is mapped first. For equal size, the first
5735 bank (CS2#) is mapped first. The first mapping is always for address
5736 0x00000000, with any additional banks following immediately to create
5737 contiguous memory starting from 0.
5739 Then, the monitor installs itself at the upper end of the SDRAM area
5740 and allocates memory for use by malloc() and for the global Board
5741 Info data; also, the exception vector code is copied to the low RAM
5742 pages, and the final stack is set up.
5744 Only after this relocation will you have a "normal" C environment;
5745 until that you are restricted in several ways, mostly because you are
5746 running from ROM, and because the code will have to be relocated to a
5750 U-Boot Porting Guide:
5751 ----------------------
5753 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
5757 int main(int argc, char *argv[])
5759 sighandler_t no_more_time;
5761 signal(SIGALRM, no_more_time);
5762 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
5764 if (available_money > available_manpower) {
5765 Pay consultant to port U-Boot;
5769 Download latest U-Boot source;
5771 Subscribe to u-boot mailing list;
5774 email("Hi, I am new to U-Boot, how do I get started?");
5777 Read the README file in the top level directory;
5778 Read http://www.denx.de/twiki/bin/view/DULG/Manual;
5779 Read applicable doc/*.README;
5780 Read the source, Luke;
5781 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
5784 if (available_money > toLocalCurrency ($2500))
5787 Add a lot of aggravation and time;
5789 if (a similar board exists) { /* hopefully... */
5790 cp -a board/<similar> board/<myboard>
5791 cp include/configs/<similar>.h include/configs/<myboard>.h
5793 Create your own board support subdirectory;
5794 Create your own board include/configs/<myboard>.h file;
5796 Edit new board/<myboard> files
5797 Edit new include/configs/<myboard>.h
5802 Add / modify source code;
5806 email("Hi, I am having problems...");
5808 Send patch file to the U-Boot email list;
5809 if (reasonable critiques)
5810 Incorporate improvements from email list code review;
5812 Defend code as written;
5818 void no_more_time (int sig)
5827 All contributions to U-Boot should conform to the Linux kernel
5828 coding style; see the file "Documentation/CodingStyle" and the script
5829 "scripts/Lindent" in your Linux kernel source directory.
5831 Source files originating from a different project (for example the
5832 MTD subsystem) are generally exempt from these guidelines and are not
5833 reformated to ease subsequent migration to newer versions of those
5836 Please note that U-Boot is implemented in C (and to some small parts in
5837 Assembler); no C++ is used, so please do not use C++ style comments (//)
5840 Please also stick to the following formatting rules:
5841 - remove any trailing white space
5842 - use TAB characters for indentation and vertical alignment, not spaces
5843 - make sure NOT to use DOS '\r\n' line feeds
5844 - do not add more than 2 consecutive empty lines to source files
5845 - do not add trailing empty lines to source files
5847 Submissions which do not conform to the standards may be returned
5848 with a request to reformat the changes.
5854 Since the number of patches for U-Boot is growing, we need to
5855 establish some rules. Submissions which do not conform to these rules
5856 may be rejected, even when they contain important and valuable stuff.
5858 Please see http://www.denx.de/wiki/U-Boot/Patches for details.
5860 Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
5861 see http://lists.denx.de/mailman/listinfo/u-boot
5863 When you send a patch, please include the following information with
5866 * For bug fixes: a description of the bug and how your patch fixes
5867 this bug. Please try to include a way of demonstrating that the
5868 patch actually fixes something.
5870 * For new features: a description of the feature and your
5873 * A CHANGELOG entry as plaintext (separate from the patch)
5875 * For major contributions, your entry to the CREDITS file
5877 * When you add support for a new board, don't forget to add a
5878 maintainer e-mail address to the boards.cfg file, too.
5880 * If your patch adds new configuration options, don't forget to
5881 document these in the README file.
5883 * The patch itself. If you are using git (which is *strongly*
5884 recommended) you can easily generate the patch using the
5885 "git format-patch". If you then use "git send-email" to send it to
5886 the U-Boot mailing list, you will avoid most of the common problems
5887 with some other mail clients.
5889 If you cannot use git, use "diff -purN OLD NEW". If your version of
5890 diff does not support these options, then get the latest version of
5893 The current directory when running this command shall be the parent
5894 directory of the U-Boot source tree (i. e. please make sure that
5895 your patch includes sufficient directory information for the
5898 We prefer patches as plain text. MIME attachments are discouraged,
5899 and compressed attachments must not be used.
5901 * If one logical set of modifications affects or creates several
5902 files, all these changes shall be submitted in a SINGLE patch file.
5904 * Changesets that contain different, unrelated modifications shall be
5905 submitted as SEPARATE patches, one patch per changeset.
5910 * Before sending the patch, run the MAKEALL script on your patched
5911 source tree and make sure that no errors or warnings are reported
5912 for any of the boards.
5914 * Keep your modifications to the necessary minimum: A patch
5915 containing several unrelated changes or arbitrary reformats will be
5916 returned with a request to re-formatting / split it.
5918 * If you modify existing code, make sure that your new code does not
5919 add to the memory footprint of the code ;-) Small is beautiful!
5920 When adding new features, these should compile conditionally only
5921 (using #ifdef), and the resulting code with the new feature
5922 disabled must not need more memory than the old code without your
5925 * Remember that there is a size limit of 100 kB per message on the
5926 u-boot mailing list. Bigger patches will be moderated. If they are
5927 reasonable and not too big, they will be acknowledged. But patches
5928 bigger than the size limit should be avoided.
projects / karo-tx-uboot.git / blob