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 MAINTAINERS 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 /arm925t Files specific to ARM 925 CPUs
143 /arm926ejs Files specific to ARM 926 CPUs
144 /arm1136 Files specific to ARM 1136 CPUs
145 /ixp Files specific to Intel XScale IXP CPUs
146 /pxa Files specific to Intel XScale PXA CPUs
147 /s3c44b0 Files specific to Samsung S3C44B0 CPUs
148 /sa1100 Files specific to Intel StrongARM SA1100 CPUs
149 /lib Architecture specific library files
150 /avr32 Files generic to AVR32 architecture
151 /cpu CPU specific files
152 /lib Architecture specific library files
153 /blackfin Files generic to Analog Devices Blackfin architecture
154 /cpu CPU specific files
155 /lib Architecture specific library files
156 /x86 Files generic to x86 architecture
157 /cpu CPU specific files
158 /lib Architecture specific library files
159 /m68k Files generic to m68k architecture
160 /cpu CPU specific files
161 /mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs
162 /mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs
163 /mcf532x Files specific to Freescale ColdFire MCF5329 CPUs
164 /mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs
165 /mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs
166 /lib Architecture specific library files
167 /microblaze Files generic to microblaze architecture
168 /cpu CPU specific files
169 /lib Architecture specific library files
170 /mips Files generic to MIPS architecture
171 /cpu CPU specific files
172 /mips32 Files specific to MIPS32 CPUs
173 /xburst Files specific to Ingenic XBurst CPUs
174 /lib Architecture specific library files
175 /nds32 Files generic to NDS32 architecture
176 /cpu CPU specific files
177 /n1213 Files specific to Andes Technology N1213 CPUs
178 /lib Architecture specific library files
179 /nios2 Files generic to Altera NIOS2 architecture
180 /cpu CPU specific files
181 /lib Architecture specific library files
182 /powerpc Files generic to PowerPC architecture
183 /cpu CPU specific files
184 /74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs
185 /mpc5xx Files specific to Freescale MPC5xx CPUs
186 /mpc5xxx Files specific to Freescale MPC5xxx CPUs
187 /mpc8xx Files specific to Freescale MPC8xx CPUs
188 /mpc824x Files specific to Freescale MPC824x CPUs
189 /mpc8260 Files specific to Freescale MPC8260 CPUs
190 /mpc85xx Files specific to Freescale MPC85xx CPUs
191 /ppc4xx Files specific to AMCC PowerPC 4xx CPUs
192 /lib Architecture specific library files
193 /sh Files generic to SH architecture
194 /cpu CPU specific files
195 /sh2 Files specific to sh2 CPUs
196 /sh3 Files specific to sh3 CPUs
197 /sh4 Files specific to sh4 CPUs
198 /lib Architecture specific library files
199 /sparc Files generic to SPARC architecture
200 /cpu CPU specific files
201 /leon2 Files specific to Gaisler LEON2 SPARC CPU
202 /leon3 Files specific to Gaisler LEON3 SPARC CPU
203 /lib Architecture specific library files
204 /api Machine/arch independent API for external apps
205 /board Board dependent files
206 /common Misc architecture independent functions
207 /disk Code for disk drive partition handling
208 /doc Documentation (don't expect too much)
209 /drivers Commonly used device drivers
210 /examples Example code for standalone applications, etc.
211 /fs Filesystem code (cramfs, ext2, jffs2, etc.)
212 /include Header Files
213 /lib Files generic to all architectures
214 /libfdt Library files to support flattened device trees
215 /lzma Library files to support LZMA decompression
216 /lzo Library files to support LZO decompression
218 /post Power On Self Test
219 /rtc Real Time Clock drivers
220 /tools Tools to build S-Record or U-Boot images, etc.
222 Software Configuration:
223 =======================
225 Configuration is usually done using C preprocessor defines; the
226 rationale behind that is to avoid dead code whenever possible.
228 There are two classes of configuration variables:
230 * Configuration _OPTIONS_:
231 These are selectable by the user and have names beginning with
234 * Configuration _SETTINGS_:
235 These depend on the hardware etc. and should not be meddled with if
236 you don't know what you're doing; they have names beginning with
239 Later we will add a configuration tool - probably similar to or even
240 identical to what's used for the Linux kernel. Right now, we have to
241 do the configuration by hand, which means creating some symbolic
242 links and editing some configuration files. We use the TQM8xxL boards
246 Selection of Processor Architecture and Board Type:
247 ---------------------------------------------------
249 For all supported boards there are ready-to-use default
250 configurations available; just type "make <board_name>_config".
252 Example: For a TQM823L module type:
257 For the Cogent platform, you need to specify the CPU type as well;
258 e.g. "make cogent_mpc8xx_config". And also configure the cogent
259 directory according to the instructions in cogent/README.
262 Configuration Options:
263 ----------------------
265 Configuration depends on the combination of board and CPU type; all
266 such information is kept in a configuration file
267 "include/configs/<board_name>.h".
269 Example: For a TQM823L module, all configuration settings are in
270 "include/configs/TQM823L.h".
273 Many of the options are named exactly as the corresponding Linux
274 kernel configuration options. The intention is to make it easier to
275 build a config tool - later.
278 The following options need to be configured:
280 - CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
282 - Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
284 - CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined)
285 Define exactly one, e.g. CONFIG_ATSTK1002
287 - CPU Module Type: (if CONFIG_COGENT is defined)
288 Define exactly one of
290 --- FIXME --- not tested yet:
291 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
292 CONFIG_CMA287_23, CONFIG_CMA287_50
294 - Motherboard Type: (if CONFIG_COGENT is defined)
295 Define exactly one of
296 CONFIG_CMA101, CONFIG_CMA102
298 - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
299 Define one or more of
302 - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
303 Define one or more of
304 CONFIG_LCD_HEARTBEAT - update a character position on
305 the LCD display every second with
308 - Board flavour: (if CONFIG_MPC8260ADS is defined)
311 CONFIG_SYS_8260ADS - original MPC8260ADS
312 CONFIG_SYS_8266ADS - MPC8266ADS
313 CONFIG_SYS_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR
314 CONFIG_SYS_8272ADS - MPC8272ADS
316 - Marvell Family Member
317 CONFIG_SYS_MVFS - define it if you want to enable
318 multiple fs option at one time
319 for marvell soc family
321 - MPC824X Family Member (if CONFIG_MPC824X is defined)
322 Define exactly one of
323 CONFIG_MPC8240, CONFIG_MPC8245
325 - 8xx CPU Options: (if using an MPC8xx CPU)
326 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if
327 get_gclk_freq() cannot work
328 e.g. if there is no 32KHz
329 reference PIT/RTC clock
330 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK
333 - 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
334 CONFIG_SYS_8xx_CPUCLK_MIN
335 CONFIG_SYS_8xx_CPUCLK_MAX
336 CONFIG_8xx_CPUCLK_DEFAULT
337 See doc/README.MPC866
339 CONFIG_SYS_MEASURE_CPUCLK
341 Define this to measure the actual CPU clock instead
342 of relying on the correctness of the configured
343 values. Mostly useful for board bringup to make sure
344 the PLL is locked at the intended frequency. Note
345 that this requires a (stable) reference clock (32 kHz
346 RTC clock or CONFIG_SYS_8XX_XIN)
348 CONFIG_SYS_DELAYED_ICACHE
350 Define this option if you want to enable the
351 ICache only when Code runs from RAM.
356 Specifies that the core is a 64-bit PowerPC implementation (implements
357 the "64" category of the Power ISA). This is necessary for ePAPR
358 compliance, among other possible reasons.
360 CONFIG_SYS_FSL_TBCLK_DIV
362 Defines the core time base clock divider ratio compared to the
363 system clock. On most PQ3 devices this is 8, on newer QorIQ
364 devices it can be 16 or 32. The ratio varies from SoC to Soc.
366 CONFIG_SYS_FSL_PCIE_COMPAT
368 Defines the string to utilize when trying to match PCIe device
369 tree nodes for the given platform.
371 CONFIG_SYS_PPC_E500_DEBUG_TLB
373 Enables a temporary TLB entry to be used during boot to work
374 around limitations in e500v1 and e500v2 external debugger
375 support. This reduces the portions of the boot code where
376 breakpoints and single stepping do not work. The value of this
377 symbol should be set to the TLB1 entry to be used for this
380 CONFIG_SYS_FSL_ERRATUM_A004510
382 Enables a workaround for erratum A004510. If set,
383 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and
384 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set.
386 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV
387 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional)
389 Defines one or two SoC revisions (low 8 bits of SVR)
390 for which the A004510 workaround should be applied.
392 The rest of SVR is either not relevant to the decision
393 of whether the erratum is present (e.g. p2040 versus
394 p2041) or is implied by the build target, which controls
395 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set.
397 See Freescale App Note 4493 for more information about
400 CONFIG_A003399_NOR_WORKAROUND
401 Enables a workaround for IFC erratum A003399. It is only
402 requred during NOR boot.
404 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY
406 This is the value to write into CCSR offset 0x18600
407 according to the A004510 workaround.
409 CONFIG_SYS_FSL_DSP_M2_RAM_ADDR
410 This value denotes start offset of M2 memory
411 which is directly connected to the DSP core.
413 CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT
414 This value denotes start offset of DSP CCSR space.
416 CONFIG_SYS_FSL_DDR_EMU
417 Specify emulator support for DDR. Some DDR features such as
418 deskew training are not available.
420 - Generic CPU options:
421 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN
423 Defines the endianess of the CPU. Implementation of those
424 values is arch specific.
426 - Intel Monahans options:
427 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO
429 Defines the Monahans run mode to oscillator
430 ratio. Valid values are 8, 16, 24, 31. The core
431 frequency is this value multiplied by 13 MHz.
433 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO
435 Defines the Monahans turbo mode to oscillator
436 ratio. Valid values are 1 (default if undefined) and
437 2. The core frequency as calculated above is multiplied
441 CONFIG_SYS_INIT_SP_OFFSET
443 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack
444 pointer. This is needed for the temporary stack before
447 CONFIG_SYS_MIPS_CACHE_MODE
449 Cache operation mode for the MIPS CPU.
450 See also arch/mips/include/asm/mipsregs.h.
452 CONF_CM_CACHABLE_NO_WA
455 CONF_CM_CACHABLE_NONCOHERENT
459 CONF_CM_CACHABLE_ACCELERATED
461 CONFIG_SYS_XWAY_EBU_BOOTCFG
463 Special option for Lantiq XWAY SoCs for booting from NOR flash.
464 See also arch/mips/cpu/mips32/start.S.
466 CONFIG_XWAY_SWAP_BYTES
468 Enable compilation of tools/xway-swap-bytes needed for Lantiq
469 XWAY SoCs for booting from NOR flash. The U-Boot image needs to
470 be swapped if a flash programmer is used.
473 CONFIG_SYS_EXCEPTION_VECTORS_HIGH
475 Select high exception vectors of the ARM core, e.g., do not
476 clear the V bit of the c1 register of CP15.
478 CONFIG_SYS_THUMB_BUILD
480 Use this flag to build U-Boot using the Thumb instruction
481 set for ARM architectures. Thumb instruction set provides
482 better code density. For ARM architectures that support
483 Thumb2 this flag will result in Thumb2 code generated by
486 CONFIG_ARM_ERRATA_716044
487 CONFIG_ARM_ERRATA_742230
488 CONFIG_ARM_ERRATA_743622
489 CONFIG_ARM_ERRATA_751472
491 If set, the workarounds for these ARM errata are applied early
492 during U-Boot startup. Note that these options force the
493 workarounds to be applied; no CPU-type/version detection
494 exists, unlike the similar options in the Linux kernel. Do not
495 set these options unless they apply!
500 The frequency of the timer returned by get_timer().
501 get_timer() must operate in milliseconds and this CONFIG
502 option must be set to 1000.
504 - Linux Kernel Interface:
507 U-Boot stores all clock information in Hz
508 internally. For binary compatibility with older Linux
509 kernels (which expect the clocks passed in the
510 bd_info data to be in MHz) the environment variable
511 "clocks_in_mhz" can be defined so that U-Boot
512 converts clock data to MHZ before passing it to the
514 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
515 "clocks_in_mhz=1" is automatically included in the
518 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
520 When transferring memsize parameter to linux, some versions
521 expect it to be in bytes, others in MB.
522 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
526 New kernel versions are expecting firmware settings to be
527 passed using flattened device trees (based on open firmware
531 * New libfdt-based support
532 * Adds the "fdt" command
533 * The bootm command automatically updates the fdt
535 OF_CPU - The proper name of the cpus node (only required for
536 MPC512X and MPC5xxx based boards).
537 OF_SOC - The proper name of the soc node (only required for
538 MPC512X and MPC5xxx based boards).
539 OF_TBCLK - The timebase frequency.
540 OF_STDOUT_PATH - The path to the console device
542 boards with QUICC Engines require OF_QE to set UCC MAC
545 CONFIG_OF_BOARD_SETUP
547 Board code has addition modification that it wants to make
548 to the flat device tree before handing it off to the kernel
552 This define fills in the correct boot CPU in the boot
553 param header, the default value is zero if undefined.
557 U-Boot can detect if an IDE device is present or not.
558 If not, and this new config option is activated, U-Boot
559 removes the ATA node from the DTS before booting Linux,
560 so the Linux IDE driver does not probe the device and
561 crash. This is needed for buggy hardware (uc101) where
562 no pull down resistor is connected to the signal IDE5V_DD7.
564 CONFIG_MACH_TYPE [relevant for ARM only][mandatory]
566 This setting is mandatory for all boards that have only one
567 machine type and must be used to specify the machine type
568 number as it appears in the ARM machine registry
569 (see http://www.arm.linux.org.uk/developer/machines/).
570 Only boards that have multiple machine types supported
571 in a single configuration file and the machine type is
572 runtime discoverable, do not have to use this setting.
574 - vxWorks boot parameters:
576 bootvx constructs a valid bootline using the following
577 environments variables: bootfile, ipaddr, serverip, hostname.
578 It loads the vxWorks image pointed bootfile.
580 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name
581 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address
582 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server
583 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters
585 CONFIG_SYS_VXWORKS_ADD_PARAMS
587 Add it at the end of the bootline. E.g "u=username pw=secret"
589 Note: If a "bootargs" environment is defined, it will overwride
590 the defaults discussed just above.
592 - Cache Configuration:
593 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot
594 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot
595 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot
597 - Cache Configuration for ARM:
598 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache
600 CONFIG_SYS_PL310_BASE - Physical base address of PL310
601 controller register space
606 Define this if you want support for Amba PrimeCell PL010 UARTs.
610 Define this if you want support for Amba PrimeCell PL011 UARTs.
614 If you have Amba PrimeCell PL011 UARTs, set this variable to
615 the clock speed of the UARTs.
619 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
620 define this to a list of base addresses for each (supported)
621 port. See e.g. include/configs/versatile.h
623 CONFIG_PL011_SERIAL_RLCR
625 Some vendor versions of PL011 serial ports (e.g. ST-Ericsson U8500)
626 have separate receive and transmit line control registers. Set
627 this variable to initialize the extra register.
629 CONFIG_PL011_SERIAL_FLUSH_ON_INIT
631 On some platforms (e.g. U8500) U-Boot is loaded by a second stage
632 boot loader that has already initialized the UART. Define this
633 variable to flush the UART at init time.
637 Depending on board, define exactly one serial port
638 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
639 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
640 console by defining CONFIG_8xx_CONS_NONE
642 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
643 port routines must be defined elsewhere
644 (i.e. serial_init(), serial_getc(), ...)
647 Enables console device for a color framebuffer. Needs following
648 defines (cf. smiLynxEM, i8042)
649 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
651 VIDEO_HW_RECTFILL graphic chip supports
654 VIDEO_HW_BITBLT graphic chip supports
655 bit-blit (cf. smiLynxEM)
656 VIDEO_VISIBLE_COLS visible pixel columns
658 VIDEO_VISIBLE_ROWS visible pixel rows
659 VIDEO_PIXEL_SIZE bytes per pixel
660 VIDEO_DATA_FORMAT graphic data format
661 (0-5, cf. cfb_console.c)
662 VIDEO_FB_ADRS framebuffer address
663 VIDEO_KBD_INIT_FCT keyboard int fct
664 (i.e. i8042_kbd_init())
665 VIDEO_TSTC_FCT test char fct
667 VIDEO_GETC_FCT get char fct
669 CONFIG_CONSOLE_CURSOR cursor drawing on/off
670 (requires blink timer
672 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
673 CONFIG_CONSOLE_TIME display time/date info in
675 (requires CONFIG_CMD_DATE)
676 CONFIG_VIDEO_LOGO display Linux logo in
678 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
679 linux_logo.h for logo.
680 Requires CONFIG_VIDEO_LOGO
681 CONFIG_CONSOLE_EXTRA_INFO
682 additional board info beside
685 When CONFIG_CFB_CONSOLE_ANSI is defined, console will support
686 a limited number of ANSI escape sequences (cursor control,
687 erase functions and limited graphics rendition control).
689 When CONFIG_CFB_CONSOLE is defined, video console is
690 default i/o. Serial console can be forced with
691 environment 'console=serial'.
693 When CONFIG_SILENT_CONSOLE is defined, all console
694 messages (by U-Boot and Linux!) can be silenced with
695 the "silent" environment variable. See
696 doc/README.silent for more information.
699 CONFIG_BAUDRATE - in bps
700 Select one of the baudrates listed in
701 CONFIG_SYS_BAUDRATE_TABLE, see below.
702 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale
704 - Console Rx buffer length
705 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define
706 the maximum receive buffer length for the SMC.
707 This option is actual only for 82xx and 8xx possible.
708 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE
709 must be defined, to setup the maximum idle timeout for
712 - Pre-Console Buffer:
713 Prior to the console being initialised (i.e. serial UART
714 initialised etc) all console output is silently discarded.
715 Defining CONFIG_PRE_CONSOLE_BUFFER will cause U-Boot to
716 buffer any console messages prior to the console being
717 initialised to a buffer of size CONFIG_PRE_CON_BUF_SZ
718 bytes located at CONFIG_PRE_CON_BUF_ADDR. The buffer is
719 a circular buffer, so if more than CONFIG_PRE_CON_BUF_SZ
720 bytes are output before the console is initialised, the
721 earlier bytes are discarded.
723 'Sane' compilers will generate smaller code if
724 CONFIG_PRE_CON_BUF_SZ is a power of 2
726 - Safe printf() functions
727 Define CONFIG_SYS_VSNPRINTF to compile in safe versions of
728 the printf() functions. These are defined in
729 include/vsprintf.h and include snprintf(), vsnprintf() and
730 so on. Code size increase is approximately 300-500 bytes.
731 If this option is not given then these functions will
732 silently discard their buffer size argument - this means
733 you are not getting any overflow checking in this case.
735 - Boot Delay: CONFIG_BOOTDELAY - in seconds
736 Delay before automatically booting the default image;
737 set to -1 to disable autoboot.
738 set to -2 to autoboot with no delay and not check for abort
739 (even when CONFIG_ZERO_BOOTDELAY_CHECK is defined).
741 See doc/README.autoboot for these options that
742 work with CONFIG_BOOTDELAY. None are required.
743 CONFIG_BOOT_RETRY_TIME
744 CONFIG_BOOT_RETRY_MIN
745 CONFIG_AUTOBOOT_KEYED
746 CONFIG_AUTOBOOT_PROMPT
747 CONFIG_AUTOBOOT_DELAY_STR
748 CONFIG_AUTOBOOT_STOP_STR
749 CONFIG_AUTOBOOT_DELAY_STR2
750 CONFIG_AUTOBOOT_STOP_STR2
751 CONFIG_ZERO_BOOTDELAY_CHECK
752 CONFIG_RESET_TO_RETRY
756 Only needed when CONFIG_BOOTDELAY is enabled;
757 define a command string that is automatically executed
758 when no character is read on the console interface
759 within "Boot Delay" after reset.
762 This can be used to pass arguments to the bootm
763 command. The value of CONFIG_BOOTARGS goes into the
764 environment value "bootargs".
766 CONFIG_RAMBOOT and CONFIG_NFSBOOT
767 The value of these goes into the environment as
768 "ramboot" and "nfsboot" respectively, and can be used
769 as a convenience, when switching between booting from
775 When this option is #defined, the existence of the
776 environment variable "preboot" will be checked
777 immediately before starting the CONFIG_BOOTDELAY
778 countdown and/or running the auto-boot command resp.
779 entering interactive mode.
781 This feature is especially useful when "preboot" is
782 automatically generated or modified. For an example
783 see the LWMON board specific code: here "preboot" is
784 modified when the user holds down a certain
785 combination of keys on the (special) keyboard when
788 - Serial Download Echo Mode:
790 If defined to 1, all characters received during a
791 serial download (using the "loads" command) are
792 echoed back. This might be needed by some terminal
793 emulations (like "cu"), but may as well just take
794 time on others. This setting #define's the initial
795 value of the "loads_echo" environment variable.
797 - Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
799 Select one of the baudrates listed in
800 CONFIG_SYS_BAUDRATE_TABLE, see below.
803 Monitor commands can be included or excluded
804 from the build by using the #include files
805 <config_cmd_all.h> and #undef'ing unwanted
806 commands, or using <config_cmd_default.h>
807 and augmenting with additional #define's
810 The default command configuration includes all commands
811 except those marked below with a "*".
813 CONFIG_CMD_ASKENV * ask for env variable
814 CONFIG_CMD_BDI bdinfo
815 CONFIG_CMD_BEDBUG * Include BedBug Debugger
816 CONFIG_CMD_BMP * BMP support
817 CONFIG_CMD_BSP * Board specific commands
818 CONFIG_CMD_BOOTD bootd
819 CONFIG_CMD_CACHE * icache, dcache
820 CONFIG_CMD_CONSOLE coninfo
821 CONFIG_CMD_CRC32 * crc32
822 CONFIG_CMD_DATE * support for RTC, date/time...
823 CONFIG_CMD_DHCP * DHCP support
824 CONFIG_CMD_DIAG * Diagnostics
825 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands
826 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command
827 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd
828 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command
829 CONFIG_CMD_DTT * Digital Therm and Thermostat
830 CONFIG_CMD_ECHO echo arguments
831 CONFIG_CMD_EDITENV edit env variable
832 CONFIG_CMD_EEPROM * EEPROM read/write support
833 CONFIG_CMD_ELF * bootelf, bootvx
834 CONFIG_CMD_ENV_CALLBACK * display details about env callbacks
835 CONFIG_CMD_ENV_FLAGS * display details about env flags
836 CONFIG_CMD_EXPORTENV * export the environment
837 CONFIG_CMD_EXT2 * ext2 command support
838 CONFIG_CMD_EXT4 * ext4 command support
839 CONFIG_CMD_SAVEENV saveenv
840 CONFIG_CMD_FDC * Floppy Disk Support
841 CONFIG_CMD_FAT * FAT command support
842 CONFIG_CMD_FDOS * Dos diskette Support
843 CONFIG_CMD_FLASH flinfo, erase, protect
844 CONFIG_CMD_FPGA FPGA device initialization support
845 CONFIG_CMD_FUSE * Device fuse support
846 CONFIG_CMD_GETTIME * Get time since boot
847 CONFIG_CMD_GO * the 'go' command (exec code)
848 CONFIG_CMD_GREPENV * search environment
849 CONFIG_CMD_HASH * calculate hash / digest
850 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control
851 CONFIG_CMD_I2C * I2C serial bus support
852 CONFIG_CMD_IDE * IDE harddisk support
853 CONFIG_CMD_IMI iminfo
854 CONFIG_CMD_IMLS List all images found in NOR flash
855 CONFIG_CMD_IMLS_NAND * List all images found in NAND flash
856 CONFIG_CMD_IMMAP * IMMR dump support
857 CONFIG_CMD_IMPORTENV * import an environment
858 CONFIG_CMD_INI * import data from an ini file into the env
859 CONFIG_CMD_IRQ * irqinfo
860 CONFIG_CMD_ITEST Integer/string test of 2 values
861 CONFIG_CMD_JFFS2 * JFFS2 Support
862 CONFIG_CMD_KGDB * kgdb
863 CONFIG_CMD_LDRINFO * ldrinfo (display Blackfin loader)
864 CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration
866 CONFIG_CMD_LOADB loadb
867 CONFIG_CMD_LOADS loads
868 CONFIG_CMD_MD5SUM * print md5 message digest
869 (requires CONFIG_CMD_MEMORY and CONFIG_MD5)
870 CONFIG_CMD_MEMINFO * Display detailed memory information
871 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
873 CONFIG_CMD_MEMTEST * mtest
874 CONFIG_CMD_MISC Misc functions like sleep etc
875 CONFIG_CMD_MMC * MMC memory mapped support
876 CONFIG_CMD_MII * MII utility commands
877 CONFIG_CMD_MTDPARTS * MTD partition support
878 CONFIG_CMD_NAND * NAND support
879 CONFIG_CMD_NET bootp, tftpboot, rarpboot
880 CONFIG_CMD_NFS NFS support
881 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands
882 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command
883 CONFIG_CMD_PCI * pciinfo
884 CONFIG_CMD_PCMCIA * PCMCIA support
885 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network
887 CONFIG_CMD_PORTIO * Port I/O
888 CONFIG_CMD_READ * Read raw data from partition
889 CONFIG_CMD_REGINFO * Register dump
890 CONFIG_CMD_RUN run command in env variable
891 CONFIG_CMD_SANDBOX * sb command to access sandbox features
892 CONFIG_CMD_SAVES * save S record dump
893 CONFIG_CMD_SCSI * SCSI Support
894 CONFIG_CMD_SDRAM * print SDRAM configuration information
895 (requires CONFIG_CMD_I2C)
896 CONFIG_CMD_SETGETDCR Support for DCR Register access
898 CONFIG_CMD_SF * Read/write/erase SPI NOR flash
899 CONFIG_CMD_SHA1SUM * print sha1 memory digest
900 (requires CONFIG_CMD_MEMORY)
901 CONFIG_CMD_SOFTSWITCH * Soft switch setting command for BF60x
902 CONFIG_CMD_SOURCE "source" command Support
903 CONFIG_CMD_SPI * SPI serial bus support
904 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode
905 CONFIG_CMD_TFTPPUT * TFTP put command (upload)
906 CONFIG_CMD_TIME * run command and report execution time (ARM specific)
907 CONFIG_CMD_TIMER * access to the system tick timer
908 CONFIG_CMD_USB * USB support
909 CONFIG_CMD_CDP * Cisco Discover Protocol support
910 CONFIG_CMD_MFSL * Microblaze FSL support
911 CONFIG_CMD_XIMG Load part of Multi Image
914 EXAMPLE: If you want all functions except of network
915 support you can write:
917 #include "config_cmd_all.h"
918 #undef CONFIG_CMD_NET
921 fdt (flattened device tree) command: CONFIG_OF_LIBFDT
923 Note: Don't enable the "icache" and "dcache" commands
924 (configuration option CONFIG_CMD_CACHE) unless you know
925 what you (and your U-Boot users) are doing. Data
926 cache cannot be enabled on systems like the 8xx or
927 8260 (where accesses to the IMMR region must be
928 uncached), and it cannot be disabled on all other
929 systems where we (mis-) use the data cache to hold an
930 initial stack and some data.
933 XXX - this list needs to get updated!
935 - Regular expression support:
937 If this variable is defined, U-Boot is linked against
938 the SLRE (Super Light Regular Expression) library,
939 which adds regex support to some commands, as for
940 example "env grep" and "setexpr".
944 If this variable is defined, U-Boot will use a device tree
945 to configure its devices, instead of relying on statically
946 compiled #defines in the board file. This option is
947 experimental and only available on a few boards. The device
948 tree is available in the global data as gd->fdt_blob.
950 U-Boot needs to get its device tree from somewhere. This can
951 be done using one of the two options below:
954 If this variable is defined, U-Boot will embed a device tree
955 binary in its image. This device tree file should be in the
956 board directory and called <soc>-<board>.dts. The binary file
957 is then picked up in board_init_f() and made available through
958 the global data structure as gd->blob.
961 If this variable is defined, U-Boot will build a device tree
962 binary. It will be called u-boot.dtb. Architecture-specific
963 code will locate it at run-time. Generally this works by:
965 cat u-boot.bin u-boot.dtb >image.bin
967 and in fact, U-Boot does this for you, creating a file called
968 u-boot-dtb.bin which is useful in the common case. You can
969 still use the individual files if you need something more
974 If this variable is defined, it enables watchdog
975 support for the SoC. There must be support in the SoC
976 specific code for a watchdog. For the 8xx and 8260
977 CPUs, the SIU Watchdog feature is enabled in the SYPCR
978 register. When supported for a specific SoC is
979 available, then no further board specific code should
983 When using a watchdog circuitry external to the used
984 SoC, then define this variable and provide board
985 specific code for the "hw_watchdog_reset" function.
988 CONFIG_VERSION_VARIABLE
989 If this variable is defined, an environment variable
990 named "ver" is created by U-Boot showing the U-Boot
991 version as printed by the "version" command.
992 Any change to this variable will be reverted at the
997 When CONFIG_CMD_DATE is selected, the type of the RTC
998 has to be selected, too. Define exactly one of the
1001 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
1002 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
1003 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC
1004 CONFIG_RTC_MC146818 - use MC146818 RTC
1005 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
1006 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
1007 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
1008 CONFIG_RTC_DS164x - use Dallas DS164x RTC
1009 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
1010 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
1011 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
1012 CONFIG_SYS_RV3029_TCR - enable trickle charger on
1015 Note that if the RTC uses I2C, then the I2C interface
1016 must also be configured. See I2C Support, below.
1019 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
1020 CONFIG_PCA953X_INFO - enable pca953x info command
1022 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
1023 chip-ngpio pairs that tell the PCA953X driver the number of
1024 pins supported by a particular chip.
1026 Note that if the GPIO device uses I2C, then the I2C interface
1027 must also be configured. See I2C Support, below.
1029 - Timestamp Support:
1031 When CONFIG_TIMESTAMP is selected, the timestamp
1032 (date and time) of an image is printed by image
1033 commands like bootm or iminfo. This option is
1034 automatically enabled when you select CONFIG_CMD_DATE .
1036 - Partition Labels (disklabels) Supported:
1037 Zero or more of the following:
1038 CONFIG_MAC_PARTITION Apple's MacOS partition table.
1039 CONFIG_DOS_PARTITION MS Dos partition table, traditional on the
1040 Intel architecture, USB sticks, etc.
1041 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc.
1042 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the
1043 bootloader. Note 2TB partition limit; see
1045 CONFIG_MTD_PARTITIONS Memory Technology Device partition table.
1047 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or
1048 CONFIG_CMD_SCSI) you must configure support for at
1049 least one non-MTD partition type as well.
1052 CONFIG_IDE_RESET_ROUTINE - this is defined in several
1053 board configurations files but used nowhere!
1055 CONFIG_IDE_RESET - is this is defined, IDE Reset will
1056 be performed by calling the function
1057 ide_set_reset(int reset)
1058 which has to be defined in a board specific file
1063 Set this to enable ATAPI support.
1068 Set this to enable support for disks larger than 137GB
1069 Also look at CONFIG_SYS_64BIT_LBA.
1070 Whithout these , LBA48 support uses 32bit variables and will 'only'
1071 support disks up to 2.1TB.
1073 CONFIG_SYS_64BIT_LBA:
1074 When enabled, makes the IDE subsystem use 64bit sector addresses.
1078 At the moment only there is only support for the
1079 SYM53C8XX SCSI controller; define
1080 CONFIG_SCSI_SYM53C8XX to enable it.
1082 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
1083 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
1084 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
1085 maximum numbers of LUNs, SCSI ID's and target
1087 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
1089 The environment variable 'scsidevs' is set to the number of
1090 SCSI devices found during the last scan.
1092 - NETWORK Support (PCI):
1094 Support for Intel 8254x/8257x gigabit chips.
1097 Utility code for direct access to the SPI bus on Intel 8257x.
1098 This does not do anything useful unless you set at least one
1099 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC.
1101 CONFIG_E1000_SPI_GENERIC
1102 Allow generic access to the SPI bus on the Intel 8257x, for
1103 example with the "sspi" command.
1106 Management command for E1000 devices. When used on devices
1107 with SPI support you can reprogram the EEPROM from U-Boot.
1109 CONFIG_E1000_FALLBACK_MAC
1110 default MAC for empty EEPROM after production.
1113 Support for Intel 82557/82559/82559ER chips.
1114 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
1115 write routine for first time initialisation.
1118 Support for Digital 2114x chips.
1119 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
1120 modem chip initialisation (KS8761/QS6611).
1123 Support for National dp83815 chips.
1126 Support for National dp8382[01] gigabit chips.
1128 - NETWORK Support (other):
1130 CONFIG_DRIVER_AT91EMAC
1131 Support for AT91RM9200 EMAC.
1134 Define this to use reduced MII inteface
1136 CONFIG_DRIVER_AT91EMAC_QUIET
1137 If this defined, the driver is quiet.
1138 The driver doen't show link status messages.
1140 CONFIG_CALXEDA_XGMAC
1141 Support for the Calxeda XGMAC device
1144 Support for SMSC's LAN91C96 chips.
1146 CONFIG_LAN91C96_BASE
1147 Define this to hold the physical address
1148 of the LAN91C96's I/O space
1150 CONFIG_LAN91C96_USE_32_BIT
1151 Define this to enable 32 bit addressing
1154 Support for SMSC's LAN91C111 chip
1156 CONFIG_SMC91111_BASE
1157 Define this to hold the physical address
1158 of the device (I/O space)
1160 CONFIG_SMC_USE_32_BIT
1161 Define this if data bus is 32 bits
1163 CONFIG_SMC_USE_IOFUNCS
1164 Define this to use i/o functions instead of macros
1165 (some hardware wont work with macros)
1167 CONFIG_DRIVER_TI_EMAC
1168 Support for davinci emac
1170 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT
1171 Define this if you have more then 3 PHYs.
1174 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
1176 CONFIG_FTGMAC100_EGIGA
1177 Define this to use GE link update with gigabit PHY.
1178 Define this if FTGMAC100 is connected to gigabit PHY.
1179 If your system has 10/100 PHY only, it might not occur
1180 wrong behavior. Because PHY usually return timeout or
1181 useless data when polling gigabit status and gigabit
1182 control registers. This behavior won't affect the
1183 correctnessof 10/100 link speed update.
1186 Support for SMSC's LAN911x and LAN921x chips
1189 Define this to hold the physical address
1190 of the device (I/O space)
1192 CONFIG_SMC911X_32_BIT
1193 Define this if data bus is 32 bits
1195 CONFIG_SMC911X_16_BIT
1196 Define this if data bus is 16 bits. If your processor
1197 automatically converts one 32 bit word to two 16 bit
1198 words you may also try CONFIG_SMC911X_32_BIT.
1201 Support for Renesas on-chip Ethernet controller
1203 CONFIG_SH_ETHER_USE_PORT
1204 Define the number of ports to be used
1206 CONFIG_SH_ETHER_PHY_ADDR
1207 Define the ETH PHY's address
1209 CONFIG_SH_ETHER_CACHE_WRITEBACK
1210 If this option is set, the driver enables cache flush.
1214 Support TPM devices.
1217 Support for i2c bus TPM devices. Only one device
1218 per system is supported at this time.
1220 CONFIG_TPM_TIS_I2C_BUS_NUMBER
1221 Define the the i2c bus number for the TPM device
1223 CONFIG_TPM_TIS_I2C_SLAVE_ADDRESS
1224 Define the TPM's address on the i2c bus
1226 CONFIG_TPM_TIS_I2C_BURST_LIMITATION
1227 Define the burst count bytes upper limit
1229 CONFIG_TPM_ATMEL_TWI
1230 Support for Atmel TWI TPM device. Requires I2C support.
1233 Support for generic parallel port TPM devices. Only one device
1234 per system is supported at this time.
1236 CONFIG_TPM_TIS_BASE_ADDRESS
1237 Base address where the generic TPM device is mapped
1238 to. Contemporary x86 systems usually map it at
1242 Add tpm monitor functions.
1243 Requires CONFIG_TPM. If CONFIG_TPM_AUTH_SESSIONS is set, also
1244 provides monitor access to authorized functions.
1247 Define this to enable the TPM support library which provides
1248 functional interfaces to some TPM commands.
1249 Requires support for a TPM device.
1251 CONFIG_TPM_AUTH_SESSIONS
1252 Define this to enable authorized functions in the TPM library.
1253 Requires CONFIG_TPM and CONFIG_SHA1.
1256 At the moment only the UHCI host controller is
1257 supported (PIP405, MIP405, MPC5200); define
1258 CONFIG_USB_UHCI to enable it.
1259 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
1260 and define CONFIG_USB_STORAGE to enable the USB
1263 Supported are USB Keyboards and USB Floppy drives
1265 MPC5200 USB requires additional defines:
1267 for 528 MHz Clock: 0x0001bbbb
1271 for differential drivers: 0x00001000
1272 for single ended drivers: 0x00005000
1273 for differential drivers on PSC3: 0x00000100
1274 for single ended drivers on PSC3: 0x00004100
1275 CONFIG_SYS_USB_EVENT_POLL
1276 May be defined to allow interrupt polling
1277 instead of using asynchronous interrupts
1279 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the
1280 txfilltuning field in the EHCI controller on reset.
1282 CONFIG_USB_HUB_MIN_POWER_ON_DELAY defines the minimum
1283 interval for usb hub power-on delay.(minimum 100msec)
1286 Define the below if you wish to use the USB console.
1287 Once firmware is rebuilt from a serial console issue the
1288 command "setenv stdin usbtty; setenv stdout usbtty" and
1289 attach your USB cable. The Unix command "dmesg" should print
1290 it has found a new device. The environment variable usbtty
1291 can be set to gserial or cdc_acm to enable your device to
1292 appear to a USB host as a Linux gserial device or a
1293 Common Device Class Abstract Control Model serial device.
1294 If you select usbtty = gserial you should be able to enumerate
1296 # modprobe usbserial vendor=0xVendorID product=0xProductID
1297 else if using cdc_acm, simply setting the environment
1298 variable usbtty to be cdc_acm should suffice. The following
1299 might be defined in YourBoardName.h
1302 Define this to build a UDC device
1305 Define this to have a tty type of device available to
1306 talk to the UDC device
1309 Define this to enable the high speed support for usb
1310 device and usbtty. If this feature is enabled, a routine
1311 int is_usbd_high_speed(void)
1312 also needs to be defined by the driver to dynamically poll
1313 whether the enumeration has succeded at high speed or full
1316 CONFIG_SYS_CONSOLE_IS_IN_ENV
1317 Define this if you want stdin, stdout &/or stderr to
1321 CONFIG_SYS_USB_EXTC_CLK 0xBLAH
1322 Derive USB clock from external clock "blah"
1323 - CONFIG_SYS_USB_EXTC_CLK 0x02
1325 CONFIG_SYS_USB_BRG_CLK 0xBLAH
1326 Derive USB clock from brgclk
1327 - CONFIG_SYS_USB_BRG_CLK 0x04
1329 If you have a USB-IF assigned VendorID then you may wish to
1330 define your own vendor specific values either in BoardName.h
1331 or directly in usbd_vendor_info.h. If you don't define
1332 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
1333 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
1334 should pretend to be a Linux device to it's target host.
1336 CONFIG_USBD_MANUFACTURER
1337 Define this string as the name of your company for
1338 - CONFIG_USBD_MANUFACTURER "my company"
1340 CONFIG_USBD_PRODUCT_NAME
1341 Define this string as the name of your product
1342 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
1344 CONFIG_USBD_VENDORID
1345 Define this as your assigned Vendor ID from the USB
1346 Implementors Forum. This *must* be a genuine Vendor ID
1347 to avoid polluting the USB namespace.
1348 - CONFIG_USBD_VENDORID 0xFFFF
1350 CONFIG_USBD_PRODUCTID
1351 Define this as the unique Product ID
1353 - CONFIG_USBD_PRODUCTID 0xFFFF
1355 - ULPI Layer Support:
1356 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via
1357 the generic ULPI layer. The generic layer accesses the ULPI PHY
1358 via the platform viewport, so you need both the genric layer and
1359 the viewport enabled. Currently only Chipidea/ARC based
1360 viewport is supported.
1361 To enable the ULPI layer support, define CONFIG_USB_ULPI and
1362 CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
1363 If your ULPI phy needs a different reference clock than the
1364 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to
1365 the appropriate value in Hz.
1368 The MMC controller on the Intel PXA is supported. To
1369 enable this define CONFIG_MMC. The MMC can be
1370 accessed from the boot prompt by mapping the device
1371 to physical memory similar to flash. Command line is
1372 enabled with CONFIG_CMD_MMC. The MMC driver also works with
1373 the FAT fs. This is enabled with CONFIG_CMD_FAT.
1376 Support for Renesas on-chip MMCIF controller
1378 CONFIG_SH_MMCIF_ADDR
1379 Define the base address of MMCIF registers
1382 Define the clock frequency for MMCIF
1384 - USB Device Firmware Update (DFU) class support:
1386 This enables the USB portion of the DFU USB class
1389 This enables the command "dfu" which is used to have
1390 U-Boot create a DFU class device via USB. This command
1391 requires that the "dfu_alt_info" environment variable be
1392 set and define the alt settings to expose to the host.
1395 This enables support for exposing (e)MMC devices via DFU.
1398 This enables support for exposing NAND devices via DFU.
1400 CONFIG_SYS_DFU_DATA_BUF_SIZE
1401 Dfu transfer uses a buffer before writing data to the
1402 raw storage device. Make the size (in bytes) of this buffer
1403 configurable. The size of this buffer is also configurable
1404 through the "dfu_bufsiz" environment variable.
1406 CONFIG_SYS_DFU_MAX_FILE_SIZE
1407 When updating files rather than the raw storage device,
1408 we use a static buffer to copy the file into and then write
1409 the buffer once we've been given the whole file. Define
1410 this to the maximum filesize (in bytes) for the buffer.
1411 Default is 4 MiB if undefined.
1413 - Journaling Flash filesystem support:
1414 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
1415 CONFIG_JFFS2_NAND_DEV
1416 Define these for a default partition on a NAND device
1418 CONFIG_SYS_JFFS2_FIRST_SECTOR,
1419 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
1420 Define these for a default partition on a NOR device
1422 CONFIG_SYS_JFFS_CUSTOM_PART
1423 Define this to create an own partition. You have to provide a
1424 function struct part_info* jffs2_part_info(int part_num)
1426 If you define only one JFFS2 partition you may also want to
1427 #define CONFIG_SYS_JFFS_SINGLE_PART 1
1428 to disable the command chpart. This is the default when you
1429 have not defined a custom partition
1431 - FAT(File Allocation Table) filesystem write function support:
1434 Define this to enable support for saving memory data as a
1435 file in FAT formatted partition.
1437 This will also enable the command "fatwrite" enabling the
1438 user to write files to FAT.
1440 CBFS (Coreboot Filesystem) support
1443 Define this to enable support for reading from a Coreboot
1444 filesystem. Available commands are cbfsinit, cbfsinfo, cbfsls
1450 Define this to enable standard (PC-Style) keyboard
1454 Standard PC keyboard driver with US (is default) and
1455 GERMAN key layout (switch via environment 'keymap=de') support.
1456 Export function i8042_kbd_init, i8042_tstc and i8042_getc
1457 for cfb_console. Supports cursor blinking.
1460 Enables a Chrome OS keyboard using the CROS_EC interface.
1461 This uses CROS_EC to communicate with a second microcontroller
1462 which provides key scans on request.
1467 Define this to enable video support (for output to
1470 CONFIG_VIDEO_CT69000
1472 Enable Chips & Technologies 69000 Video chip
1474 CONFIG_VIDEO_SMI_LYNXEM
1475 Enable Silicon Motion SMI 712/710/810 Video chip. The
1476 video output is selected via environment 'videoout'
1477 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
1480 For the CT69000 and SMI_LYNXEM drivers, videomode is
1481 selected via environment 'videomode'. Two different ways
1483 - "videomode=num" 'num' is a standard LiLo mode numbers.
1484 Following standard modes are supported (* is default):
1486 Colors 640x480 800x600 1024x768 1152x864 1280x1024
1487 -------------+---------------------------------------------
1488 8 bits | 0x301* 0x303 0x305 0x161 0x307
1489 15 bits | 0x310 0x313 0x316 0x162 0x319
1490 16 bits | 0x311 0x314 0x317 0x163 0x31A
1491 24 bits | 0x312 0x315 0x318 ? 0x31B
1492 -------------+---------------------------------------------
1493 (i.e. setenv videomode 317; saveenv; reset;)
1495 - "videomode=bootargs" all the video parameters are parsed
1496 from the bootargs. (See drivers/video/videomodes.c)
1499 CONFIG_VIDEO_SED13806
1500 Enable Epson SED13806 driver. This driver supports 8bpp
1501 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
1502 or CONFIG_VIDEO_SED13806_16BPP
1505 Enable the Freescale DIU video driver. Reference boards for
1506 SOCs that have a DIU should define this macro to enable DIU
1507 support, and should also define these other macros:
1513 CONFIG_VIDEO_SW_CURSOR
1514 CONFIG_VGA_AS_SINGLE_DEVICE
1516 CONFIG_VIDEO_BMP_LOGO
1518 The DIU driver will look for the 'video-mode' environment
1519 variable, and if defined, enable the DIU as a console during
1520 boot. See the documentation file README.video for a
1521 description of this variable.
1525 Enable the VGA video / BIOS for x86. The alternative if you
1526 are using coreboot is to use the coreboot frame buffer
1533 Define this to enable a custom keyboard support.
1534 This simply calls drv_keyboard_init() which must be
1535 defined in your board-specific files.
1536 The only board using this so far is RBC823.
1538 - LCD Support: CONFIG_LCD
1540 Define this to enable LCD support (for output to LCD
1541 display); also select one of the supported displays
1542 by defining one of these:
1546 HITACHI TX09D70VM1CCA, 3.5", 240x320.
1548 CONFIG_NEC_NL6448AC33:
1550 NEC NL6448AC33-18. Active, color, single scan.
1552 CONFIG_NEC_NL6448BC20
1554 NEC NL6448BC20-08. 6.5", 640x480.
1555 Active, color, single scan.
1557 CONFIG_NEC_NL6448BC33_54
1559 NEC NL6448BC33-54. 10.4", 640x480.
1560 Active, color, single scan.
1564 Sharp 320x240. Active, color, single scan.
1565 It isn't 16x9, and I am not sure what it is.
1567 CONFIG_SHARP_LQ64D341
1569 Sharp LQ64D341 display, 640x480.
1570 Active, color, single scan.
1574 HLD1045 display, 640x480.
1575 Active, color, single scan.
1579 Optrex CBL50840-2 NF-FW 99 22 M5
1581 Hitachi LMG6912RPFC-00T
1585 320x240. Black & white.
1587 Normally display is black on white background; define
1588 CONFIG_SYS_WHITE_ON_BLACK to get it inverted.
1590 CONFIG_LCD_ALIGNMENT
1592 Normally the LCD is page-aligned (tyically 4KB). If this is
1593 defined then the LCD will be aligned to this value instead.
1594 For ARM it is sometimes useful to use MMU_SECTION_SIZE
1595 here, since it is cheaper to change data cache settings on
1596 a per-section basis.
1598 CONFIG_CONSOLE_SCROLL_LINES
1600 When the console need to be scrolled, this is the number of
1601 lines to scroll by. It defaults to 1. Increasing this makes
1602 the console jump but can help speed up operation when scrolling
1607 Support drawing of RLE8-compressed bitmaps on the LCD.
1611 Enables an 'i2c edid' command which can read EDID
1612 information over I2C from an attached LCD display.
1614 - Splash Screen Support: CONFIG_SPLASH_SCREEN
1616 If this option is set, the environment is checked for
1617 a variable "splashimage". If found, the usual display
1618 of logo, copyright and system information on the LCD
1619 is suppressed and the BMP image at the address
1620 specified in "splashimage" is loaded instead. The
1621 console is redirected to the "nulldev", too. This
1622 allows for a "silent" boot where a splash screen is
1623 loaded very quickly after power-on.
1625 CONFIG_SPLASHIMAGE_GUARD
1627 If this option is set, then U-Boot will prevent the environment
1628 variable "splashimage" from being set to a problematic address
1629 (see README.displaying-bmps and README.arm-unaligned-accesses).
1630 This option is useful for targets where, due to alignment
1631 restrictions, an improperly aligned BMP image will cause a data
1632 abort. If you think you will not have problems with unaligned
1633 accesses (for example because your toolchain prevents them)
1634 there is no need to set this option.
1636 CONFIG_SPLASH_SCREEN_ALIGN
1638 If this option is set the splash image can be freely positioned
1639 on the screen. Environment variable "splashpos" specifies the
1640 position as "x,y". If a positive number is given it is used as
1641 number of pixel from left/top. If a negative number is given it
1642 is used as number of pixel from right/bottom. You can also
1643 specify 'm' for centering the image.
1646 setenv splashpos m,m
1647 => image at center of screen
1649 setenv splashpos 30,20
1650 => image at x = 30 and y = 20
1652 setenv splashpos -10,m
1653 => vertically centered image
1654 at x = dspWidth - bmpWidth - 9
1656 - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
1658 If this option is set, additionally to standard BMP
1659 images, gzipped BMP images can be displayed via the
1660 splashscreen support or the bmp command.
1662 - Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
1664 If this option is set, 8-bit RLE compressed BMP images
1665 can be displayed via the splashscreen support or the
1668 - Do compresssing for memory range:
1671 If this option is set, it would use zlib deflate method
1672 to compress the specified memory at its best effort.
1674 - Compression support:
1677 If this option is set, support for bzip2 compressed
1678 images is included. If not, only uncompressed and gzip
1679 compressed images are supported.
1681 NOTE: the bzip2 algorithm requires a lot of RAM, so
1682 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
1687 If this option is set, support for lzma compressed
1690 Note: The LZMA algorithm adds between 2 and 4KB of code and it
1691 requires an amount of dynamic memory that is given by the
1694 (1846 + 768 << (lc + lp)) * sizeof(uint16)
1696 Where lc and lp stand for, respectively, Literal context bits
1697 and Literal pos bits.
1699 This value is upper-bounded by 14MB in the worst case. Anyway,
1700 for a ~4MB large kernel image, we have lc=3 and lp=0 for a
1701 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is
1702 a very small buffer.
1704 Use the lzmainfo tool to determinate the lc and lp values and
1705 then calculate the amount of needed dynamic memory (ensuring
1706 the appropriate CONFIG_SYS_MALLOC_LEN value).
1711 The address of PHY on MII bus.
1713 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1715 The clock frequency of the MII bus
1719 If this option is set, support for speed/duplex
1720 detection of gigabit PHY is included.
1722 CONFIG_PHY_RESET_DELAY
1724 Some PHY like Intel LXT971A need extra delay after
1725 reset before any MII register access is possible.
1726 For such PHY, set this option to the usec delay
1727 required. (minimum 300usec for LXT971A)
1729 CONFIG_PHY_CMD_DELAY (ppc4xx)
1731 Some PHY like Intel LXT971A need extra delay after
1732 command issued before MII status register can be read
1742 Define a default value for Ethernet address to use
1743 for the respective Ethernet interface, in case this
1744 is not determined automatically.
1749 Define a default value for the IP address to use for
1750 the default Ethernet interface, in case this is not
1751 determined through e.g. bootp.
1752 (Environment variable "ipaddr")
1754 - Server IP address:
1757 Defines a default value for the IP address of a TFTP
1758 server to contact when using the "tftboot" command.
1759 (Environment variable "serverip")
1761 CONFIG_KEEP_SERVERADDR
1763 Keeps the server's MAC address, in the env 'serveraddr'
1764 for passing to bootargs (like Linux's netconsole option)
1766 - Gateway IP address:
1769 Defines a default value for the IP address of the
1770 default router where packets to other networks are
1772 (Environment variable "gatewayip")
1777 Defines a default value for the subnet mask (or
1778 routing prefix) which is used to determine if an IP
1779 address belongs to the local subnet or needs to be
1780 forwarded through a router.
1781 (Environment variable "netmask")
1783 - Multicast TFTP Mode:
1786 Defines whether you want to support multicast TFTP as per
1787 rfc-2090; for example to work with atftp. Lets lots of targets
1788 tftp down the same boot image concurrently. Note: the Ethernet
1789 driver in use must provide a function: mcast() to join/leave a
1792 - BOOTP Recovery Mode:
1793 CONFIG_BOOTP_RANDOM_DELAY
1795 If you have many targets in a network that try to
1796 boot using BOOTP, you may want to avoid that all
1797 systems send out BOOTP requests at precisely the same
1798 moment (which would happen for instance at recovery
1799 from a power failure, when all systems will try to
1800 boot, thus flooding the BOOTP server. Defining
1801 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1802 inserted before sending out BOOTP requests. The
1803 following delays are inserted then:
1805 1st BOOTP request: delay 0 ... 1 sec
1806 2nd BOOTP request: delay 0 ... 2 sec
1807 3rd BOOTP request: delay 0 ... 4 sec
1809 BOOTP requests: delay 0 ... 8 sec
1811 - DHCP Advanced Options:
1812 You can fine tune the DHCP functionality by defining
1813 CONFIG_BOOTP_* symbols:
1815 CONFIG_BOOTP_SUBNETMASK
1816 CONFIG_BOOTP_GATEWAY
1817 CONFIG_BOOTP_HOSTNAME
1818 CONFIG_BOOTP_NISDOMAIN
1819 CONFIG_BOOTP_BOOTPATH
1820 CONFIG_BOOTP_BOOTFILESIZE
1823 CONFIG_BOOTP_SEND_HOSTNAME
1824 CONFIG_BOOTP_NTPSERVER
1825 CONFIG_BOOTP_TIMEOFFSET
1826 CONFIG_BOOTP_VENDOREX
1827 CONFIG_BOOTP_MAY_FAIL
1829 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
1830 environment variable, not the BOOTP server.
1832 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found
1833 after the configured retry count, the call will fail
1834 instead of starting over. This can be used to fail over
1835 to Link-local IP address configuration if the DHCP server
1838 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
1839 serverip from a DHCP server, it is possible that more
1840 than one DNS serverip is offered to the client.
1841 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1842 serverip will be stored in the additional environment
1843 variable "dnsip2". The first DNS serverip is always
1844 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
1847 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1848 to do a dynamic update of a DNS server. To do this, they
1849 need the hostname of the DHCP requester.
1850 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
1851 of the "hostname" environment variable is passed as
1852 option 12 to the DHCP server.
1854 CONFIG_BOOTP_DHCP_REQUEST_DELAY
1856 A 32bit value in microseconds for a delay between
1857 receiving a "DHCP Offer" and sending the "DHCP Request".
1858 This fixes a problem with certain DHCP servers that don't
1859 respond 100% of the time to a "DHCP request". E.g. On an
1860 AT91RM9200 processor running at 180MHz, this delay needed
1861 to be *at least* 15,000 usec before a Windows Server 2003
1862 DHCP server would reply 100% of the time. I recommend at
1863 least 50,000 usec to be safe. The alternative is to hope
1864 that one of the retries will be successful but note that
1865 the DHCP timeout and retry process takes a longer than
1868 - Link-local IP address negotiation:
1869 Negotiate with other link-local clients on the local network
1870 for an address that doesn't require explicit configuration.
1871 This is especially useful if a DHCP server cannot be guaranteed
1872 to exist in all environments that the device must operate.
1874 See doc/README.link-local for more information.
1877 CONFIG_CDP_DEVICE_ID
1879 The device id used in CDP trigger frames.
1881 CONFIG_CDP_DEVICE_ID_PREFIX
1883 A two character string which is prefixed to the MAC address
1888 A printf format string which contains the ascii name of
1889 the port. Normally is set to "eth%d" which sets
1890 eth0 for the first Ethernet, eth1 for the second etc.
1892 CONFIG_CDP_CAPABILITIES
1894 A 32bit integer which indicates the device capabilities;
1895 0x00000010 for a normal host which does not forwards.
1899 An ascii string containing the version of the software.
1903 An ascii string containing the name of the platform.
1907 A 32bit integer sent on the trigger.
1909 CONFIG_CDP_POWER_CONSUMPTION
1911 A 16bit integer containing the power consumption of the
1912 device in .1 of milliwatts.
1914 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1916 A byte containing the id of the VLAN.
1918 - Status LED: CONFIG_STATUS_LED
1920 Several configurations allow to display the current
1921 status using a LED. For instance, the LED will blink
1922 fast while running U-Boot code, stop blinking as
1923 soon as a reply to a BOOTP request was received, and
1924 start blinking slow once the Linux kernel is running
1925 (supported by a status LED driver in the Linux
1926 kernel). Defining CONFIG_STATUS_LED enables this
1929 - CAN Support: CONFIG_CAN_DRIVER
1931 Defining CONFIG_CAN_DRIVER enables CAN driver support
1932 on those systems that support this (optional)
1933 feature, like the TQM8xxL modules.
1935 - I2C Support: CONFIG_SYS_I2C
1937 This enable the NEW i2c subsystem, and will allow you to use
1938 i2c commands at the u-boot command line (as long as you set
1939 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c
1940 based realtime clock chips or other i2c devices. See
1941 common/cmd_i2c.c for a description of the command line
1944 ported i2c driver to the new framework:
1945 - drivers/i2c/soft_i2c.c:
1946 - activate first bus with CONFIG_SYS_I2C_SOFT define
1947 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE
1948 for defining speed and slave address
1949 - activate second bus with I2C_SOFT_DECLARATIONS2 define
1950 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2
1951 for defining speed and slave address
1952 - activate third bus with I2C_SOFT_DECLARATIONS3 define
1953 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3
1954 for defining speed and slave address
1955 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define
1956 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4
1957 for defining speed and slave address
1959 - drivers/i2c/fsl_i2c.c:
1960 - activate i2c driver with CONFIG_SYS_I2C_FSL
1961 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register
1962 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and
1963 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first
1965 - If your board supports a second fsl i2c bus, define
1966 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset
1967 CONFIG_SYS_FSL_I2C2_SPEED for the speed and
1968 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the
1971 - drivers/i2c/tegra_i2c.c:
1972 - activate this driver with CONFIG_SYS_I2C_TEGRA
1973 - This driver adds 4 i2c buses with a fix speed from
1974 100000 and the slave addr 0!
1976 - drivers/i2c/ppc4xx_i2c.c
1977 - activate this driver with CONFIG_SYS_I2C_PPC4XX
1978 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0
1979 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1
1983 CONFIG_SYS_NUM_I2C_BUSES
1984 Hold the number of i2c busses you want to use. If you
1985 don't use/have i2c muxes on your i2c bus, this
1986 is equal to CONFIG_SYS_NUM_I2C_ADAPTERS, and you can
1989 CONFIG_SYS_I2C_DIRECT_BUS
1990 define this, if you don't use i2c muxes on your hardware.
1991 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can
1994 CONFIG_SYS_I2C_MAX_HOPS
1995 define how many muxes are maximal consecutively connected
1996 on one i2c bus. If you not use i2c muxes, omit this
1999 CONFIG_SYS_I2C_BUSES
2000 hold a list of busses you want to use, only used if
2001 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example
2002 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and
2003 CONFIG_SYS_NUM_I2C_BUSES = 9:
2005 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \
2006 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \
2007 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \
2008 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \
2009 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \
2010 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \
2011 {1, {I2C_NULL_HOP}}, \
2012 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \
2013 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \
2017 bus 0 on adapter 0 without a mux
2018 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1
2019 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2
2020 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3
2021 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4
2022 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5
2023 bus 6 on adapter 1 without a mux
2024 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1
2025 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2
2027 If you do not have i2c muxes on your board, omit this define.
2029 - Legacy I2C Support: CONFIG_HARD_I2C
2031 NOTE: It is intended to move drivers to CONFIG_SYS_I2C which
2032 provides the following compelling advantages:
2034 - more than one i2c adapter is usable
2035 - approved multibus support
2036 - better i2c mux support
2038 ** Please consider updating your I2C driver now. **
2040 These enable legacy I2C serial bus commands. Defining
2041 CONFIG_HARD_I2C will include the appropriate I2C driver
2042 for the selected CPU.
2044 This will allow you to use i2c commands at the u-boot
2045 command line (as long as you set CONFIG_CMD_I2C in
2046 CONFIG_COMMANDS) and communicate with i2c based realtime
2047 clock chips. See common/cmd_i2c.c for a description of the
2048 command line interface.
2050 CONFIG_HARD_I2C selects a hardware I2C controller.
2052 There are several other quantities that must also be
2053 defined when you define CONFIG_HARD_I2C.
2055 In both cases you will need to define CONFIG_SYS_I2C_SPEED
2056 to be the frequency (in Hz) at which you wish your i2c bus
2057 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie
2058 the CPU's i2c node address).
2060 Now, the u-boot i2c code for the mpc8xx
2061 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node
2062 and so its address should therefore be cleared to 0 (See,
2063 eg, MPC823e User's Manual p.16-473). So, set
2064 CONFIG_SYS_I2C_SLAVE to 0.
2066 CONFIG_SYS_I2C_INIT_MPC5XXX
2068 When a board is reset during an i2c bus transfer
2069 chips might think that the current transfer is still
2070 in progress. Reset the slave devices by sending start
2071 commands until the slave device responds.
2073 That's all that's required for CONFIG_HARD_I2C.
2075 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT)
2076 then the following macros need to be defined (examples are
2077 from include/configs/lwmon.h):
2081 (Optional). Any commands necessary to enable the I2C
2082 controller or configure ports.
2084 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
2088 (Only for MPC8260 CPU). The I/O port to use (the code
2089 assumes both bits are on the same port). Valid values
2090 are 0..3 for ports A..D.
2094 The code necessary to make the I2C data line active
2095 (driven). If the data line is open collector, this
2098 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
2102 The code necessary to make the I2C data line tri-stated
2103 (inactive). If the data line is open collector, this
2106 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
2110 Code that returns true if the I2C data line is high,
2113 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
2117 If <bit> is true, sets the I2C data line high. If it
2118 is false, it clears it (low).
2120 eg: #define I2C_SDA(bit) \
2121 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
2122 else immr->im_cpm.cp_pbdat &= ~PB_SDA
2126 If <bit> is true, sets the I2C clock line high. If it
2127 is false, it clears it (low).
2129 eg: #define I2C_SCL(bit) \
2130 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
2131 else immr->im_cpm.cp_pbdat &= ~PB_SCL
2135 This delay is invoked four times per clock cycle so this
2136 controls the rate of data transfer. The data rate thus
2137 is 1 / (I2C_DELAY * 4). Often defined to be something
2140 #define I2C_DELAY udelay(2)
2142 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
2144 If your arch supports the generic GPIO framework (asm/gpio.h),
2145 then you may alternatively define the two GPIOs that are to be
2146 used as SCL / SDA. Any of the previous I2C_xxx macros will
2147 have GPIO-based defaults assigned to them as appropriate.
2149 You should define these to the GPIO value as given directly to
2150 the generic GPIO functions.
2152 CONFIG_SYS_I2C_INIT_BOARD
2154 When a board is reset during an i2c bus transfer
2155 chips might think that the current transfer is still
2156 in progress. On some boards it is possible to access
2157 the i2c SCLK line directly, either by using the
2158 processor pin as a GPIO or by having a second pin
2159 connected to the bus. If this option is defined a
2160 custom i2c_init_board() routine in boards/xxx/board.c
2161 is run early in the boot sequence.
2163 CONFIG_SYS_I2C_BOARD_LATE_INIT
2165 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is
2166 defined a custom i2c_board_late_init() routine in
2167 boards/xxx/board.c is run AFTER the operations in i2c_init()
2168 is completed. This callpoint can be used to unreset i2c bus
2169 using CPU i2c controller register accesses for CPUs whose i2c
2170 controller provide such a method. It is called at the end of
2171 i2c_init() to allow i2c_init operations to setup the i2c bus
2172 controller on the CPU (e.g. setting bus speed & slave address).
2174 CONFIG_I2CFAST (PPC405GP|PPC405EP only)
2176 This option enables configuration of bi_iic_fast[] flags
2177 in u-boot bd_info structure based on u-boot environment
2178 variable "i2cfast". (see also i2cfast)
2180 CONFIG_I2C_MULTI_BUS
2182 This option allows the use of multiple I2C buses, each of which
2183 must have a controller. At any point in time, only one bus is
2184 active. To switch to a different bus, use the 'i2c dev' command.
2185 Note that bus numbering is zero-based.
2187 CONFIG_SYS_I2C_NOPROBES
2189 This option specifies a list of I2C devices that will be skipped
2190 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
2191 is set, specify a list of bus-device pairs. Otherwise, specify
2192 a 1D array of device addresses
2195 #undef CONFIG_I2C_MULTI_BUS
2196 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
2198 will skip addresses 0x50 and 0x68 on a board with one I2C bus
2200 #define CONFIG_I2C_MULTI_BUS
2201 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
2203 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
2205 CONFIG_SYS_SPD_BUS_NUM
2207 If defined, then this indicates the I2C bus number for DDR SPD.
2208 If not defined, then U-Boot assumes that SPD is on I2C bus 0.
2210 CONFIG_SYS_RTC_BUS_NUM
2212 If defined, then this indicates the I2C bus number for the RTC.
2213 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
2215 CONFIG_SYS_DTT_BUS_NUM
2217 If defined, then this indicates the I2C bus number for the DTT.
2218 If not defined, then U-Boot assumes that DTT is on I2C bus 0.
2220 CONFIG_SYS_I2C_DTT_ADDR:
2222 If defined, specifies the I2C address of the DTT device.
2223 If not defined, then U-Boot uses predefined value for
2224 specified DTT device.
2226 CONFIG_SOFT_I2C_READ_REPEATED_START
2228 defining this will force the i2c_read() function in
2229 the soft_i2c driver to perform an I2C repeated start
2230 between writing the address pointer and reading the
2231 data. If this define is omitted the default behaviour
2232 of doing a stop-start sequence will be used. Most I2C
2233 devices can use either method, but some require one or
2236 - SPI Support: CONFIG_SPI
2238 Enables SPI driver (so far only tested with
2239 SPI EEPROM, also an instance works with Crystal A/D and
2240 D/As on the SACSng board)
2244 Enables the driver for SPI controller on SuperH. Currently
2245 only SH7757 is supported.
2249 Enables extended (16-bit) SPI EEPROM addressing.
2250 (symmetrical to CONFIG_I2C_X)
2254 Enables a software (bit-bang) SPI driver rather than
2255 using hardware support. This is a general purpose
2256 driver that only requires three general I/O port pins
2257 (two outputs, one input) to function. If this is
2258 defined, the board configuration must define several
2259 SPI configuration items (port pins to use, etc). For
2260 an example, see include/configs/sacsng.h.
2264 Enables a hardware SPI driver for general-purpose reads
2265 and writes. As with CONFIG_SOFT_SPI, the board configuration
2266 must define a list of chip-select function pointers.
2267 Currently supported on some MPC8xxx processors. For an
2268 example, see include/configs/mpc8349emds.h.
2272 Enables the driver for the SPI controllers on i.MX and MXC
2273 SoCs. Currently i.MX31/35/51 are supported.
2275 - FPGA Support: CONFIG_FPGA
2277 Enables FPGA subsystem.
2279 CONFIG_FPGA_<vendor>
2281 Enables support for specific chip vendors.
2284 CONFIG_FPGA_<family>
2286 Enables support for FPGA family.
2287 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
2291 Specify the number of FPGA devices to support.
2293 CONFIG_SYS_FPGA_PROG_FEEDBACK
2295 Enable printing of hash marks during FPGA configuration.
2297 CONFIG_SYS_FPGA_CHECK_BUSY
2299 Enable checks on FPGA configuration interface busy
2300 status by the configuration function. This option
2301 will require a board or device specific function to
2306 If defined, a function that provides delays in the FPGA
2307 configuration driver.
2309 CONFIG_SYS_FPGA_CHECK_CTRLC
2310 Allow Control-C to interrupt FPGA configuration
2312 CONFIG_SYS_FPGA_CHECK_ERROR
2314 Check for configuration errors during FPGA bitfile
2315 loading. For example, abort during Virtex II
2316 configuration if the INIT_B line goes low (which
2317 indicated a CRC error).
2319 CONFIG_SYS_FPGA_WAIT_INIT
2321 Maximum time to wait for the INIT_B line to deassert
2322 after PROB_B has been deasserted during a Virtex II
2323 FPGA configuration sequence. The default time is 500
2326 CONFIG_SYS_FPGA_WAIT_BUSY
2328 Maximum time to wait for BUSY to deassert during
2329 Virtex II FPGA configuration. The default is 5 ms.
2331 CONFIG_SYS_FPGA_WAIT_CONFIG
2333 Time to wait after FPGA configuration. The default is
2336 - Configuration Management:
2339 If defined, this string will be added to the U-Boot
2340 version information (U_BOOT_VERSION)
2342 - Vendor Parameter Protection:
2344 U-Boot considers the values of the environment
2345 variables "serial#" (Board Serial Number) and
2346 "ethaddr" (Ethernet Address) to be parameters that
2347 are set once by the board vendor / manufacturer, and
2348 protects these variables from casual modification by
2349 the user. Once set, these variables are read-only,
2350 and write or delete attempts are rejected. You can
2351 change this behaviour:
2353 If CONFIG_ENV_OVERWRITE is #defined in your config
2354 file, the write protection for vendor parameters is
2355 completely disabled. Anybody can change or delete
2358 Alternatively, if you #define _both_ CONFIG_ETHADDR
2359 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
2360 Ethernet address is installed in the environment,
2361 which can be changed exactly ONCE by the user. [The
2362 serial# is unaffected by this, i. e. it remains
2365 The same can be accomplished in a more flexible way
2366 for any variable by configuring the type of access
2367 to allow for those variables in the ".flags" variable
2368 or define CONFIG_ENV_FLAGS_LIST_STATIC.
2373 Define this variable to enable the reservation of
2374 "protected RAM", i. e. RAM which is not overwritten
2375 by U-Boot. Define CONFIG_PRAM to hold the number of
2376 kB you want to reserve for pRAM. You can overwrite
2377 this default value by defining an environment
2378 variable "pram" to the number of kB you want to
2379 reserve. Note that the board info structure will
2380 still show the full amount of RAM. If pRAM is
2381 reserved, a new environment variable "mem" will
2382 automatically be defined to hold the amount of
2383 remaining RAM in a form that can be passed as boot
2384 argument to Linux, for instance like that:
2386 setenv bootargs ... mem=\${mem}
2389 This way you can tell Linux not to use this memory,
2390 either, which results in a memory region that will
2391 not be affected by reboots.
2393 *WARNING* If your board configuration uses automatic
2394 detection of the RAM size, you must make sure that
2395 this memory test is non-destructive. So far, the
2396 following board configurations are known to be
2399 IVMS8, IVML24, SPD8xx, TQM8xxL,
2400 HERMES, IP860, RPXlite, LWMON,
2403 - Access to physical memory region (> 4GB)
2404 Some basic support is provided for operations on memory not
2405 normally accessible to U-Boot - e.g. some architectures
2406 support access to more than 4GB of memory on 32-bit
2407 machines using physical address extension or similar.
2408 Define CONFIG_PHYSMEM to access this basic support, which
2409 currently only supports clearing the memory.
2414 Define this variable to stop the system in case of a
2415 fatal error, so that you have to reset it manually.
2416 This is probably NOT a good idea for an embedded
2417 system where you want the system to reboot
2418 automatically as fast as possible, but it may be
2419 useful during development since you can try to debug
2420 the conditions that lead to the situation.
2422 CONFIG_NET_RETRY_COUNT
2424 This variable defines the number of retries for
2425 network operations like ARP, RARP, TFTP, or BOOTP
2426 before giving up the operation. If not defined, a
2427 default value of 5 is used.
2431 Timeout waiting for an ARP reply in milliseconds.
2435 Timeout in milliseconds used in NFS protocol.
2436 If you encounter "ERROR: Cannot umount" in nfs command,
2437 try longer timeout such as
2438 #define CONFIG_NFS_TIMEOUT 10000UL
2440 - Command Interpreter:
2441 CONFIG_AUTO_COMPLETE
2443 Enable auto completion of commands using TAB.
2445 Note that this feature has NOT been implemented yet
2446 for the "hush" shell.
2449 CONFIG_SYS_HUSH_PARSER
2451 Define this variable to enable the "hush" shell (from
2452 Busybox) as command line interpreter, thus enabling
2453 powerful command line syntax like
2454 if...then...else...fi conditionals or `&&' and '||'
2455 constructs ("shell scripts").
2457 If undefined, you get the old, much simpler behaviour
2458 with a somewhat smaller memory footprint.
2461 CONFIG_SYS_PROMPT_HUSH_PS2
2463 This defines the secondary prompt string, which is
2464 printed when the command interpreter needs more input
2465 to complete a command. Usually "> ".
2469 In the current implementation, the local variables
2470 space and global environment variables space are
2471 separated. Local variables are those you define by
2472 simply typing `name=value'. To access a local
2473 variable later on, you have write `$name' or
2474 `${name}'; to execute the contents of a variable
2475 directly type `$name' at the command prompt.
2477 Global environment variables are those you use
2478 setenv/printenv to work with. To run a command stored
2479 in such a variable, you need to use the run command,
2480 and you must not use the '$' sign to access them.
2482 To store commands and special characters in a
2483 variable, please use double quotation marks
2484 surrounding the whole text of the variable, instead
2485 of the backslashes before semicolons and special
2488 - Commandline Editing and History:
2489 CONFIG_CMDLINE_EDITING
2491 Enable editing and History functions for interactive
2492 commandline input operations
2494 - Default Environment:
2495 CONFIG_EXTRA_ENV_SETTINGS
2497 Define this to contain any number of null terminated
2498 strings (variable = value pairs) that will be part of
2499 the default environment compiled into the boot image.
2501 For example, place something like this in your
2502 board's config file:
2504 #define CONFIG_EXTRA_ENV_SETTINGS \
2508 Warning: This method is based on knowledge about the
2509 internal format how the environment is stored by the
2510 U-Boot code. This is NOT an official, exported
2511 interface! Although it is unlikely that this format
2512 will change soon, there is no guarantee either.
2513 You better know what you are doing here.
2515 Note: overly (ab)use of the default environment is
2516 discouraged. Make sure to check other ways to preset
2517 the environment like the "source" command or the
2520 CONFIG_ENV_VARS_UBOOT_CONFIG
2522 Define this in order to add variables describing the
2523 U-Boot build configuration to the default environment.
2524 These will be named arch, cpu, board, vendor, and soc.
2526 Enabling this option will cause the following to be defined:
2534 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG
2536 Define this in order to add variables describing certain
2537 run-time determined information about the hardware to the
2538 environment. These will be named board_name, board_rev.
2540 CONFIG_DELAY_ENVIRONMENT
2542 Normally the environment is loaded when the board is
2543 intialised so that it is available to U-Boot. This inhibits
2544 that so that the environment is not available until
2545 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL
2546 this is instead controlled by the value of
2547 /config/load-environment.
2549 - DataFlash Support:
2550 CONFIG_HAS_DATAFLASH
2552 Defining this option enables DataFlash features and
2553 allows to read/write in Dataflash via the standard
2556 - Serial Flash support
2559 Defining this option enables SPI flash commands
2560 'sf probe/read/write/erase/update'.
2562 Usage requires an initial 'probe' to define the serial
2563 flash parameters, followed by read/write/erase/update
2566 The following defaults may be provided by the platform
2567 to handle the common case when only a single serial
2568 flash is present on the system.
2570 CONFIG_SF_DEFAULT_BUS Bus identifier
2571 CONFIG_SF_DEFAULT_CS Chip-select
2572 CONFIG_SF_DEFAULT_MODE (see include/spi.h)
2573 CONFIG_SF_DEFAULT_SPEED in Hz
2577 Define this option to include a destructive SPI flash
2580 CONFIG_SPI_FLASH_BAR Ban/Extended Addr Reg
2582 Define this option to use the Bank addr/Extended addr
2583 support on SPI flashes which has size > 16Mbytes.
2585 - SystemACE Support:
2588 Adding this option adds support for Xilinx SystemACE
2589 chips attached via some sort of local bus. The address
2590 of the chip must also be defined in the
2591 CONFIG_SYS_SYSTEMACE_BASE macro. For example:
2593 #define CONFIG_SYSTEMACE
2594 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000
2596 When SystemACE support is added, the "ace" device type
2597 becomes available to the fat commands, i.e. fatls.
2599 - TFTP Fixed UDP Port:
2602 If this is defined, the environment variable tftpsrcp
2603 is used to supply the TFTP UDP source port value.
2604 If tftpsrcp isn't defined, the normal pseudo-random port
2605 number generator is used.
2607 Also, the environment variable tftpdstp is used to supply
2608 the TFTP UDP destination port value. If tftpdstp isn't
2609 defined, the normal port 69 is used.
2611 The purpose for tftpsrcp is to allow a TFTP server to
2612 blindly start the TFTP transfer using the pre-configured
2613 target IP address and UDP port. This has the effect of
2614 "punching through" the (Windows XP) firewall, allowing
2615 the remainder of the TFTP transfer to proceed normally.
2616 A better solution is to properly configure the firewall,
2617 but sometimes that is not allowed.
2622 This enables a generic 'hash' command which can produce
2623 hashes / digests from a few algorithms (e.g. SHA1, SHA256).
2627 Enable the hash verify command (hash -v). This adds to code
2630 CONFIG_SHA1 - support SHA1 hashing
2631 CONFIG_SHA256 - support SHA256 hashing
2633 Note: There is also a sha1sum command, which should perhaps
2634 be deprecated in favour of 'hash sha1'.
2639 This enables the RSA algorithm used for FIT image verification
2640 in U-Boot. See doc/uImage/signature for more information.
2642 The signing part is build into mkimage regardless of this
2646 - Show boot progress:
2647 CONFIG_SHOW_BOOT_PROGRESS
2649 Defining this option allows to add some board-
2650 specific code (calling a user-provided function
2651 "show_boot_progress(int)") that enables you to show
2652 the system's boot progress on some display (for
2653 example, some LED's) on your board. At the moment,
2654 the following checkpoints are implemented:
2656 - Detailed boot stage timing
2658 Define this option to get detailed timing of each stage
2659 of the boot process.
2661 CONFIG_BOOTSTAGE_USER_COUNT
2662 This is the number of available user bootstage records.
2663 Each time you call bootstage_mark(BOOTSTAGE_ID_ALLOC, ...)
2664 a new ID will be allocated from this stash. If you exceed
2665 the limit, recording will stop.
2667 CONFIG_BOOTSTAGE_REPORT
2668 Define this to print a report before boot, similar to this:
2670 Timer summary in microseconds:
2673 3,575,678 3,575,678 board_init_f start
2674 3,575,695 17 arch_cpu_init A9
2675 3,575,777 82 arch_cpu_init done
2676 3,659,598 83,821 board_init_r start
2677 3,910,375 250,777 main_loop
2678 29,916,167 26,005,792 bootm_start
2679 30,361,327 445,160 start_kernel
2681 CONFIG_CMD_BOOTSTAGE
2682 Add a 'bootstage' command which supports printing a report
2683 and un/stashing of bootstage data.
2685 CONFIG_BOOTSTAGE_FDT
2686 Stash the bootstage information in the FDT. A root 'bootstage'
2687 node is created with each bootstage id as a child. Each child
2688 has a 'name' property and either 'mark' containing the
2689 mark time in microsecond, or 'accum' containing the
2690 accumulated time for that bootstage id in microseconds.
2695 name = "board_init_f";
2704 Code in the Linux kernel can find this in /proc/devicetree.
2706 Legacy uImage format:
2709 1 common/cmd_bootm.c before attempting to boot an image
2710 -1 common/cmd_bootm.c Image header has bad magic number
2711 2 common/cmd_bootm.c Image header has correct magic number
2712 -2 common/cmd_bootm.c Image header has bad checksum
2713 3 common/cmd_bootm.c Image header has correct checksum
2714 -3 common/cmd_bootm.c Image data has bad checksum
2715 4 common/cmd_bootm.c Image data has correct checksum
2716 -4 common/cmd_bootm.c Image is for unsupported architecture
2717 5 common/cmd_bootm.c Architecture check OK
2718 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
2719 6 common/cmd_bootm.c Image Type check OK
2720 -6 common/cmd_bootm.c gunzip uncompression error
2721 -7 common/cmd_bootm.c Unimplemented compression type
2722 7 common/cmd_bootm.c Uncompression OK
2723 8 common/cmd_bootm.c No uncompress/copy overwrite error
2724 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
2726 9 common/image.c Start initial ramdisk verification
2727 -10 common/image.c Ramdisk header has bad magic number
2728 -11 common/image.c Ramdisk header has bad checksum
2729 10 common/image.c Ramdisk header is OK
2730 -12 common/image.c Ramdisk data has bad checksum
2731 11 common/image.c Ramdisk data has correct checksum
2732 12 common/image.c Ramdisk verification complete, start loading
2733 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
2734 13 common/image.c Start multifile image verification
2735 14 common/image.c No initial ramdisk, no multifile, continue.
2737 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
2739 -30 arch/powerpc/lib/board.c Fatal error, hang the system
2740 -31 post/post.c POST test failed, detected by post_output_backlog()
2741 -32 post/post.c POST test failed, detected by post_run_single()
2743 34 common/cmd_doc.c before loading a Image from a DOC device
2744 -35 common/cmd_doc.c Bad usage of "doc" command
2745 35 common/cmd_doc.c correct usage of "doc" command
2746 -36 common/cmd_doc.c No boot device
2747 36 common/cmd_doc.c correct boot device
2748 -37 common/cmd_doc.c Unknown Chip ID on boot device
2749 37 common/cmd_doc.c correct chip ID found, device available
2750 -38 common/cmd_doc.c Read Error on boot device
2751 38 common/cmd_doc.c reading Image header from DOC device OK
2752 -39 common/cmd_doc.c Image header has bad magic number
2753 39 common/cmd_doc.c Image header has correct magic number
2754 -40 common/cmd_doc.c Error reading Image from DOC device
2755 40 common/cmd_doc.c Image header has correct magic number
2756 41 common/cmd_ide.c before loading a Image from a IDE device
2757 -42 common/cmd_ide.c Bad usage of "ide" command
2758 42 common/cmd_ide.c correct usage of "ide" command
2759 -43 common/cmd_ide.c No boot device
2760 43 common/cmd_ide.c boot device found
2761 -44 common/cmd_ide.c Device not available
2762 44 common/cmd_ide.c Device available
2763 -45 common/cmd_ide.c wrong partition selected
2764 45 common/cmd_ide.c partition selected
2765 -46 common/cmd_ide.c Unknown partition table
2766 46 common/cmd_ide.c valid partition table found
2767 -47 common/cmd_ide.c Invalid partition type
2768 47 common/cmd_ide.c correct partition type
2769 -48 common/cmd_ide.c Error reading Image Header on boot device
2770 48 common/cmd_ide.c reading Image Header from IDE device OK
2771 -49 common/cmd_ide.c Image header has bad magic number
2772 49 common/cmd_ide.c Image header has correct magic number
2773 -50 common/cmd_ide.c Image header has bad checksum
2774 50 common/cmd_ide.c Image header has correct checksum
2775 -51 common/cmd_ide.c Error reading Image from IDE device
2776 51 common/cmd_ide.c reading Image from IDE device OK
2777 52 common/cmd_nand.c before loading a Image from a NAND device
2778 -53 common/cmd_nand.c Bad usage of "nand" command
2779 53 common/cmd_nand.c correct usage of "nand" command
2780 -54 common/cmd_nand.c No boot device
2781 54 common/cmd_nand.c boot device found
2782 -55 common/cmd_nand.c Unknown Chip ID on boot device
2783 55 common/cmd_nand.c correct chip ID found, device available
2784 -56 common/cmd_nand.c Error reading Image Header on boot device
2785 56 common/cmd_nand.c reading Image Header from NAND device OK
2786 -57 common/cmd_nand.c Image header has bad magic number
2787 57 common/cmd_nand.c Image header has correct magic number
2788 -58 common/cmd_nand.c Error reading Image from NAND device
2789 58 common/cmd_nand.c reading Image from NAND device OK
2791 -60 common/env_common.c Environment has a bad CRC, using default
2793 64 net/eth.c starting with Ethernet configuration.
2794 -64 net/eth.c no Ethernet found.
2795 65 net/eth.c Ethernet found.
2797 -80 common/cmd_net.c usage wrong
2798 80 common/cmd_net.c before calling NetLoop()
2799 -81 common/cmd_net.c some error in NetLoop() occurred
2800 81 common/cmd_net.c NetLoop() back without error
2801 -82 common/cmd_net.c size == 0 (File with size 0 loaded)
2802 82 common/cmd_net.c trying automatic boot
2803 83 common/cmd_net.c running "source" command
2804 -83 common/cmd_net.c some error in automatic boot or "source" command
2805 84 common/cmd_net.c end without errors
2810 100 common/cmd_bootm.c Kernel FIT Image has correct format
2811 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
2812 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
2813 -101 common/cmd_bootm.c Can't get configuration for kernel subimage
2814 102 common/cmd_bootm.c Kernel unit name specified
2815 -103 common/cmd_bootm.c Can't get kernel subimage node offset
2816 103 common/cmd_bootm.c Found configuration node
2817 104 common/cmd_bootm.c Got kernel subimage node offset
2818 -104 common/cmd_bootm.c Kernel subimage hash verification failed
2819 105 common/cmd_bootm.c Kernel subimage hash verification OK
2820 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
2821 106 common/cmd_bootm.c Architecture check OK
2822 -106 common/cmd_bootm.c Kernel subimage has wrong type
2823 107 common/cmd_bootm.c Kernel subimage type OK
2824 -107 common/cmd_bootm.c Can't get kernel subimage data/size
2825 108 common/cmd_bootm.c Got kernel subimage data/size
2826 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
2827 -109 common/cmd_bootm.c Can't get kernel subimage type
2828 -110 common/cmd_bootm.c Can't get kernel subimage comp
2829 -111 common/cmd_bootm.c Can't get kernel subimage os
2830 -112 common/cmd_bootm.c Can't get kernel subimage load address
2831 -113 common/cmd_bootm.c Image uncompress/copy overwrite error
2833 120 common/image.c Start initial ramdisk verification
2834 -120 common/image.c Ramdisk FIT image has incorrect format
2835 121 common/image.c Ramdisk FIT image has correct format
2836 122 common/image.c No ramdisk subimage unit name, using configuration
2837 -122 common/image.c Can't get configuration for ramdisk subimage
2838 123 common/image.c Ramdisk unit name specified
2839 -124 common/image.c Can't get ramdisk subimage node offset
2840 125 common/image.c Got ramdisk subimage node offset
2841 -125 common/image.c Ramdisk subimage hash verification failed
2842 126 common/image.c Ramdisk subimage hash verification OK
2843 -126 common/image.c Ramdisk subimage for unsupported architecture
2844 127 common/image.c Architecture check OK
2845 -127 common/image.c Can't get ramdisk subimage data/size
2846 128 common/image.c Got ramdisk subimage data/size
2847 129 common/image.c Can't get ramdisk load address
2848 -129 common/image.c Got ramdisk load address
2850 -130 common/cmd_doc.c Incorrect FIT image format
2851 131 common/cmd_doc.c FIT image format OK
2853 -140 common/cmd_ide.c Incorrect FIT image format
2854 141 common/cmd_ide.c FIT image format OK
2856 -150 common/cmd_nand.c Incorrect FIT image format
2857 151 common/cmd_nand.c FIT image format OK
2859 - FIT image support:
2861 Enable support for the FIT uImage format.
2863 CONFIG_FIT_BEST_MATCH
2864 When no configuration is explicitly selected, default to the
2865 one whose fdt's compatibility field best matches that of
2866 U-Boot itself. A match is considered "best" if it matches the
2867 most specific compatibility entry of U-Boot's fdt's root node.
2868 The order of entries in the configuration's fdt is ignored.
2870 CONFIG_FIT_SIGNATURE
2871 This option enables signature verification of FIT uImages,
2872 using a hash signed and verified using RSA. See
2873 doc/uImage.FIT/signature.txt for more details.
2875 - Standalone program support:
2876 CONFIG_STANDALONE_LOAD_ADDR
2878 This option defines a board specific value for the
2879 address where standalone program gets loaded, thus
2880 overwriting the architecture dependent default
2883 - Frame Buffer Address:
2886 Define CONFIG_FB_ADDR if you want to use specific
2887 address for frame buffer. This is typically the case
2888 when using a graphics controller has separate video
2889 memory. U-Boot will then place the frame buffer at
2890 the given address instead of dynamically reserving it
2891 in system RAM by calling lcd_setmem(), which grabs
2892 the memory for the frame buffer depending on the
2893 configured panel size.
2895 Please see board_init_f function.
2897 - Automatic software updates via TFTP server
2899 CONFIG_UPDATE_TFTP_CNT_MAX
2900 CONFIG_UPDATE_TFTP_MSEC_MAX
2902 These options enable and control the auto-update feature;
2903 for a more detailed description refer to doc/README.update.
2905 - MTD Support (mtdparts command, UBI support)
2908 Adds the MTD device infrastructure from the Linux kernel.
2909 Needed for mtdparts command support.
2911 CONFIG_MTD_PARTITIONS
2913 Adds the MTD partitioning infrastructure from the Linux
2914 kernel. Needed for UBI support.
2919 Adds commands for interacting with MTD partitions formatted
2920 with the UBI flash translation layer
2922 Requires also defining CONFIG_RBTREE
2924 CONFIG_UBI_SILENCE_MSG
2926 Make the verbose messages from UBI stop printing. This leaves
2927 warnings and errors enabled.
2932 Adds commands for interacting with UBI volumes formatted as
2933 UBIFS. UBIFS is read-only in u-boot.
2935 Requires UBI support as well as CONFIG_LZO
2937 CONFIG_UBIFS_SILENCE_MSG
2939 Make the verbose messages from UBIFS stop printing. This leaves
2940 warnings and errors enabled.
2944 Enable building of SPL globally.
2947 LDSCRIPT for linking the SPL binary.
2949 CONFIG_SPL_MAX_FOOTPRINT
2950 Maximum size in memory allocated to the SPL, BSS included.
2951 When defined, the linker checks that the actual memory
2952 used by SPL from _start to __bss_end does not exceed it.
2953 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
2954 must not be both defined at the same time.
2957 Maximum size of the SPL image (text, data, rodata, and
2958 linker lists sections), BSS excluded.
2959 When defined, the linker checks that the actual size does
2962 CONFIG_SPL_TEXT_BASE
2963 TEXT_BASE for linking the SPL binary.
2965 CONFIG_SPL_RELOC_TEXT_BASE
2966 Address to relocate to. If unspecified, this is equal to
2967 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done).
2969 CONFIG_SPL_BSS_START_ADDR
2970 Link address for the BSS within the SPL binary.
2972 CONFIG_SPL_BSS_MAX_SIZE
2973 Maximum size in memory allocated to the SPL BSS.
2974 When defined, the linker checks that the actual memory used
2975 by SPL from __bss_start to __bss_end does not exceed it.
2976 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
2977 must not be both defined at the same time.
2980 Adress of the start of the stack SPL will use
2982 CONFIG_SPL_RELOC_STACK
2983 Adress of the start of the stack SPL will use after
2984 relocation. If unspecified, this is equal to
2987 CONFIG_SYS_SPL_MALLOC_START
2988 Starting address of the malloc pool used in SPL.
2990 CONFIG_SYS_SPL_MALLOC_SIZE
2991 The size of the malloc pool used in SPL.
2993 CONFIG_SPL_FRAMEWORK
2994 Enable the SPL framework under common/. This framework
2995 supports MMC, NAND and YMODEM loading of U-Boot and NAND
2996 NAND loading of the Linux Kernel.
2998 CONFIG_SPL_DISPLAY_PRINT
2999 For ARM, enable an optional function to print more information
3000 about the running system.
3002 CONFIG_SPL_INIT_MINIMAL
3003 Arch init code should be built for a very small image
3005 CONFIG_SPL_LIBCOMMON_SUPPORT
3006 Support for common/libcommon.o in SPL binary
3008 CONFIG_SPL_LIBDISK_SUPPORT
3009 Support for disk/libdisk.o in SPL binary
3011 CONFIG_SPL_I2C_SUPPORT
3012 Support for drivers/i2c/libi2c.o in SPL binary
3014 CONFIG_SPL_GPIO_SUPPORT
3015 Support for drivers/gpio/libgpio.o in SPL binary
3017 CONFIG_SPL_MMC_SUPPORT
3018 Support for drivers/mmc/libmmc.o in SPL binary
3020 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR,
3021 CONFIG_SYS_U_BOOT_MAX_SIZE_SECTORS,
3022 CONFIG_SYS_MMC_SD_FAT_BOOT_PARTITION
3023 Address, size and partition on the MMC to load U-Boot from
3024 when the MMC is being used in raw mode.
3026 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR
3027 Sector to load kernel uImage from when MMC is being
3028 used in raw mode (for Falcon mode)
3030 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR,
3031 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS
3032 Sector and number of sectors to load kernel argument
3033 parameters from when MMC is being used in raw mode
3036 CONFIG_SPL_FAT_SUPPORT
3037 Support for fs/fat/libfat.o in SPL binary
3039 CONFIG_SPL_FAT_LOAD_PAYLOAD_NAME
3040 Filename to read to load U-Boot when reading from FAT
3042 CONFIG_SPL_FAT_LOAD_KERNEL_NAME
3043 Filename to read to load kernel uImage when reading
3044 from FAT (for Falcon mode)
3046 CONFIG_SPL_FAT_LOAD_ARGS_NAME
3047 Filename to read to load kernel argument parameters
3048 when reading from FAT (for Falcon mode)
3050 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND
3051 Set this for NAND SPL on PPC mpc83xx targets, so that
3052 start.S waits for the rest of the SPL to load before
3053 continuing (the hardware starts execution after just
3054 loading the first page rather than the full 4K).
3056 CONFIG_SPL_NAND_BASE
3057 Include nand_base.c in the SPL. Requires
3058 CONFIG_SPL_NAND_DRIVERS.
3060 CONFIG_SPL_NAND_DRIVERS
3061 SPL uses normal NAND drivers, not minimal drivers.
3064 Include standard software ECC in the SPL
3066 CONFIG_SPL_NAND_SIMPLE
3067 Support for NAND boot using simple NAND drivers that
3068 expose the cmd_ctrl() interface.
3070 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
3071 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
3072 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
3073 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE,
3074 CONFIG_SYS_NAND_ECCBYTES
3075 Defines the size and behavior of the NAND that SPL uses
3078 CONFIG_SYS_NAND_U_BOOT_OFFS
3079 Location in NAND to read U-Boot from
3081 CONFIG_SYS_NAND_U_BOOT_DST
3082 Location in memory to load U-Boot to
3084 CONFIG_SYS_NAND_U_BOOT_SIZE
3085 Size of image to load
3087 CONFIG_SYS_NAND_U_BOOT_START
3088 Entry point in loaded image to jump to
3090 CONFIG_SYS_NAND_HW_ECC_OOBFIRST
3091 Define this if you need to first read the OOB and then the
3092 data. This is used for example on davinci plattforms.
3094 CONFIG_SPL_OMAP3_ID_NAND
3095 Support for an OMAP3-specific set of functions to return the
3096 ID and MFR of the first attached NAND chip, if present.
3098 CONFIG_SPL_SERIAL_SUPPORT
3099 Support for drivers/serial/libserial.o in SPL binary
3101 CONFIG_SPL_SPI_FLASH_SUPPORT
3102 Support for drivers/mtd/spi/libspi_flash.o in SPL binary
3104 CONFIG_SPL_SPI_SUPPORT
3105 Support for drivers/spi/libspi.o in SPL binary
3107 CONFIG_SPL_RAM_DEVICE
3108 Support for running image already present in ram, in SPL binary
3110 CONFIG_SPL_LIBGENERIC_SUPPORT
3111 Support for lib/libgeneric.o in SPL binary
3113 CONFIG_SPL_ENV_SUPPORT
3114 Support for the environment operating in SPL binary
3116 CONFIG_SPL_NET_SUPPORT
3117 Support for the net/libnet.o in SPL binary.
3118 It conflicts with SPL env from storage medium specified by
3119 CONFIG_ENV_IS_xxx but CONFIG_ENV_IS_NOWHERE
3122 Image offset to which the SPL should be padded before appending
3123 the SPL payload. By default, this is defined as
3124 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
3125 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
3126 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
3129 Final target image containing SPL and payload. Some SPLs
3130 use an arch-specific makefile fragment instead, for
3131 example if more than one image needs to be produced.
3133 CONFIG_FIT_SPL_PRINT
3134 Printing information about a FIT image adds quite a bit of
3135 code to SPL. So this is normally disabled in SPL. Use this
3136 option to re-enable it. This will affect the output of the
3137 bootm command when booting a FIT image.
3142 [so far only for SMDK2400 boards]
3144 - Modem support enable:
3145 CONFIG_MODEM_SUPPORT
3147 - RTS/CTS Flow control enable:
3150 - Modem debug support:
3151 CONFIG_MODEM_SUPPORT_DEBUG
3153 Enables debugging stuff (char screen[1024], dbg())
3154 for modem support. Useful only with BDI2000.
3156 - Interrupt support (PPC):
3158 There are common interrupt_init() and timer_interrupt()
3159 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
3160 for CPU specific initialization. interrupt_init_cpu()
3161 should set decrementer_count to appropriate value. If
3162 CPU resets decrementer automatically after interrupt
3163 (ppc4xx) it should set decrementer_count to zero.
3164 timer_interrupt() calls timer_interrupt_cpu() for CPU
3165 specific handling. If board has watchdog / status_led
3166 / other_activity_monitor it works automatically from
3167 general timer_interrupt().
3171 In the target system modem support is enabled when a
3172 specific key (key combination) is pressed during
3173 power-on. Otherwise U-Boot will boot normally
3174 (autoboot). The key_pressed() function is called from
3175 board_init(). Currently key_pressed() is a dummy
3176 function, returning 1 and thus enabling modem
3179 If there are no modem init strings in the
3180 environment, U-Boot proceed to autoboot; the
3181 previous output (banner, info printfs) will be
3184 See also: doc/README.Modem
3186 Board initialization settings:
3187 ------------------------------
3189 During Initialization u-boot calls a number of board specific functions
3190 to allow the preparation of board specific prerequisites, e.g. pin setup
3191 before drivers are initialized. To enable these callbacks the
3192 following configuration macros have to be defined. Currently this is
3193 architecture specific, so please check arch/your_architecture/lib/board.c
3194 typically in board_init_f() and board_init_r().
3196 - CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
3197 - CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
3198 - CONFIG_BOARD_LATE_INIT: Call board_late_init()
3199 - CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init()
3201 Configuration Settings:
3202 -----------------------
3204 - CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
3205 undefine this when you're short of memory.
3207 - CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
3208 width of the commands listed in the 'help' command output.
3210 - CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
3211 prompt for user input.
3213 - CONFIG_SYS_CBSIZE: Buffer size for input from the Console
3215 - CONFIG_SYS_PBSIZE: Buffer size for Console output
3217 - CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
3219 - CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
3220 the application (usually a Linux kernel) when it is
3223 - CONFIG_SYS_BAUDRATE_TABLE:
3224 List of legal baudrate settings for this board.
3226 - CONFIG_SYS_CONSOLE_INFO_QUIET
3227 Suppress display of console information at boot.
3229 - CONFIG_SYS_CONSOLE_IS_IN_ENV
3230 If the board specific function
3231 extern int overwrite_console (void);
3232 returns 1, the stdin, stderr and stdout are switched to the
3233 serial port, else the settings in the environment are used.
3235 - CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE
3236 Enable the call to overwrite_console().
3238 - CONFIG_SYS_CONSOLE_ENV_OVERWRITE
3239 Enable overwrite of previous console environment settings.
3241 - CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
3242 Begin and End addresses of the area used by the
3245 - CONFIG_SYS_ALT_MEMTEST:
3246 Enable an alternate, more extensive memory test.
3248 - CONFIG_SYS_MEMTEST_SCRATCH:
3249 Scratch address used by the alternate memory test
3250 You only need to set this if address zero isn't writeable
3252 - CONFIG_SYS_MEM_TOP_HIDE (PPC only):
3253 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
3254 this specified memory area will get subtracted from the top
3255 (end) of RAM and won't get "touched" at all by U-Boot. By
3256 fixing up gd->ram_size the Linux kernel should gets passed
3257 the now "corrected" memory size and won't touch it either.
3258 This should work for arch/ppc and arch/powerpc. Only Linux
3259 board ports in arch/powerpc with bootwrapper support that
3260 recalculate the memory size from the SDRAM controller setup
3261 will have to get fixed in Linux additionally.
3263 This option can be used as a workaround for the 440EPx/GRx
3264 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
3267 WARNING: Please make sure that this value is a multiple of
3268 the Linux page size (normally 4k). If this is not the case,
3269 then the end address of the Linux memory will be located at a
3270 non page size aligned address and this could cause major
3273 - CONFIG_SYS_LOADS_BAUD_CHANGE:
3274 Enable temporary baudrate change while serial download
3276 - CONFIG_SYS_SDRAM_BASE:
3277 Physical start address of SDRAM. _Must_ be 0 here.
3279 - CONFIG_SYS_MBIO_BASE:
3280 Physical start address of Motherboard I/O (if using a
3283 - CONFIG_SYS_FLASH_BASE:
3284 Physical start address of Flash memory.
3286 - CONFIG_SYS_MONITOR_BASE:
3287 Physical start address of boot monitor code (set by
3288 make config files to be same as the text base address
3289 (CONFIG_SYS_TEXT_BASE) used when linking) - same as
3290 CONFIG_SYS_FLASH_BASE when booting from flash.
3292 - CONFIG_SYS_MONITOR_LEN:
3293 Size of memory reserved for monitor code, used to
3294 determine _at_compile_time_ (!) if the environment is
3295 embedded within the U-Boot image, or in a separate
3298 - CONFIG_SYS_MALLOC_LEN:
3299 Size of DRAM reserved for malloc() use.
3301 - CONFIG_SYS_BOOTM_LEN:
3302 Normally compressed uImages are limited to an
3303 uncompressed size of 8 MBytes. If this is not enough,
3304 you can define CONFIG_SYS_BOOTM_LEN in your board config file
3305 to adjust this setting to your needs.
3307 - CONFIG_SYS_BOOTMAPSZ:
3308 Maximum size of memory mapped by the startup code of
3309 the Linux kernel; all data that must be processed by
3310 the Linux kernel (bd_info, boot arguments, FDT blob if
3311 used) must be put below this limit, unless "bootm_low"
3312 enviroment variable is defined and non-zero. In such case
3313 all data for the Linux kernel must be between "bootm_low"
3314 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
3315 variable "bootm_mapsize" will override the value of
3316 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
3317 then the value in "bootm_size" will be used instead.
3319 - CONFIG_SYS_BOOT_RAMDISK_HIGH:
3320 Enable initrd_high functionality. If defined then the
3321 initrd_high feature is enabled and the bootm ramdisk subcommand
3324 - CONFIG_SYS_BOOT_GET_CMDLINE:
3325 Enables allocating and saving kernel cmdline in space between
3326 "bootm_low" and "bootm_low" + BOOTMAPSZ.
3328 - CONFIG_SYS_BOOT_GET_KBD:
3329 Enables allocating and saving a kernel copy of the bd_info in
3330 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
3332 - CONFIG_SYS_MAX_FLASH_BANKS:
3333 Max number of Flash memory banks
3335 - CONFIG_SYS_MAX_FLASH_SECT:
3336 Max number of sectors on a Flash chip
3338 - CONFIG_SYS_FLASH_ERASE_TOUT:
3339 Timeout for Flash erase operations (in ms)
3341 - CONFIG_SYS_FLASH_WRITE_TOUT:
3342 Timeout for Flash write operations (in ms)
3344 - CONFIG_SYS_FLASH_LOCK_TOUT
3345 Timeout for Flash set sector lock bit operation (in ms)
3347 - CONFIG_SYS_FLASH_UNLOCK_TOUT
3348 Timeout for Flash clear lock bits operation (in ms)
3350 - CONFIG_SYS_FLASH_PROTECTION
3351 If defined, hardware flash sectors protection is used
3352 instead of U-Boot software protection.
3354 - CONFIG_SYS_DIRECT_FLASH_TFTP:
3356 Enable TFTP transfers directly to flash memory;
3357 without this option such a download has to be
3358 performed in two steps: (1) download to RAM, and (2)
3359 copy from RAM to flash.
3361 The two-step approach is usually more reliable, since
3362 you can check if the download worked before you erase
3363 the flash, but in some situations (when system RAM is
3364 too limited to allow for a temporary copy of the
3365 downloaded image) this option may be very useful.
3367 - CONFIG_SYS_FLASH_CFI:
3368 Define if the flash driver uses extra elements in the
3369 common flash structure for storing flash geometry.
3371 - CONFIG_FLASH_CFI_DRIVER
3372 This option also enables the building of the cfi_flash driver
3373 in the drivers directory
3375 - CONFIG_FLASH_CFI_MTD
3376 This option enables the building of the cfi_mtd driver
3377 in the drivers directory. The driver exports CFI flash
3380 - CONFIG_SYS_FLASH_USE_BUFFER_WRITE
3381 Use buffered writes to flash.
3383 - CONFIG_FLASH_SPANSION_S29WS_N
3384 s29ws-n MirrorBit flash has non-standard addresses for buffered
3387 - CONFIG_SYS_FLASH_QUIET_TEST
3388 If this option is defined, the common CFI flash doesn't
3389 print it's warning upon not recognized FLASH banks. This
3390 is useful, if some of the configured banks are only
3391 optionally available.
3393 - CONFIG_FLASH_SHOW_PROGRESS
3394 If defined (must be an integer), print out countdown
3395 digits and dots. Recommended value: 45 (9..1) for 80
3396 column displays, 15 (3..1) for 40 column displays.
3398 - CONFIG_FLASH_VERIFY
3399 If defined, the content of the flash (destination) is compared
3400 against the source after the write operation. An error message
3401 will be printed when the contents are not identical.
3402 Please note that this option is useless in nearly all cases,
3403 since such flash programming errors usually are detected earlier
3404 while unprotecting/erasing/programming. Please only enable
3405 this option if you really know what you are doing.
3407 - CONFIG_SYS_RX_ETH_BUFFER:
3408 Defines the number of Ethernet receive buffers. On some
3409 Ethernet controllers it is recommended to set this value
3410 to 8 or even higher (EEPRO100 or 405 EMAC), since all
3411 buffers can be full shortly after enabling the interface
3412 on high Ethernet traffic.
3413 Defaults to 4 if not defined.
3415 - CONFIG_ENV_MAX_ENTRIES
3417 Maximum number of entries in the hash table that is used
3418 internally to store the environment settings. The default
3419 setting is supposed to be generous and should work in most
3420 cases. This setting can be used to tune behaviour; see
3421 lib/hashtable.c for details.
3423 - CONFIG_ENV_FLAGS_LIST_DEFAULT
3424 - CONFIG_ENV_FLAGS_LIST_STATIC
3425 Enable validation of the values given to enviroment variables when
3426 calling env set. Variables can be restricted to only decimal,
3427 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined,
3428 the variables can also be restricted to IP address or MAC address.
3430 The format of the list is:
3431 type_attribute = [s|d|x|b|i|m]
3432 access_atribute = [a|r|o|c]
3433 attributes = type_attribute[access_atribute]
3434 entry = variable_name[:attributes]
3437 The type attributes are:
3438 s - String (default)
3441 b - Boolean ([1yYtT|0nNfF])
3445 The access attributes are:
3451 - CONFIG_ENV_FLAGS_LIST_DEFAULT
3452 Define this to a list (string) to define the ".flags"
3453 envirnoment variable in the default or embedded environment.
3455 - CONFIG_ENV_FLAGS_LIST_STATIC
3456 Define this to a list (string) to define validation that
3457 should be done if an entry is not found in the ".flags"
3458 environment variable. To override a setting in the static
3459 list, simply add an entry for the same variable name to the
3462 - CONFIG_ENV_ACCESS_IGNORE_FORCE
3463 If defined, don't allow the -f switch to env set override variable
3466 - CONFIG_SYS_GENERIC_BOARD
3467 This selects the architecture-generic board system instead of the
3468 architecture-specific board files. It is intended to move boards
3469 to this new framework over time. Defining this will disable the
3470 arch/foo/lib/board.c file and use common/board_f.c and
3471 common/board_r.c instead. To use this option your architecture
3472 must support it (i.e. must define __HAVE_ARCH_GENERIC_BOARD in
3473 its config.mk file). If you find problems enabling this option on
3474 your board please report the problem and send patches!
3476 - CONFIG_SYS_SYM_OFFSETS
3477 This is set by architectures that use offsets for link symbols
3478 instead of absolute values. So bss_start is obtained using an
3479 offset _bss_start_ofs from CONFIG_SYS_TEXT_BASE, rather than
3480 directly. You should not need to touch this setting.
3482 - CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC (OMAP only)
3483 This is set by OMAP boards for the max time that reset should
3484 be asserted. See doc/README.omap-reset-time for details on how
3485 the value can be calulated on a given board.
3487 The following definitions that deal with the placement and management
3488 of environment data (variable area); in general, we support the
3489 following configurations:
3491 - CONFIG_BUILD_ENVCRC:
3493 Builds up envcrc with the target environment so that external utils
3494 may easily extract it and embed it in final U-Boot images.
3496 - CONFIG_ENV_IS_IN_FLASH:
3498 Define this if the environment is in flash memory.
3500 a) The environment occupies one whole flash sector, which is
3501 "embedded" in the text segment with the U-Boot code. This
3502 happens usually with "bottom boot sector" or "top boot
3503 sector" type flash chips, which have several smaller
3504 sectors at the start or the end. For instance, such a
3505 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
3506 such a case you would place the environment in one of the
3507 4 kB sectors - with U-Boot code before and after it. With
3508 "top boot sector" type flash chips, you would put the
3509 environment in one of the last sectors, leaving a gap
3510 between U-Boot and the environment.
3512 - CONFIG_ENV_OFFSET:
3514 Offset of environment data (variable area) to the
3515 beginning of flash memory; for instance, with bottom boot
3516 type flash chips the second sector can be used: the offset
3517 for this sector is given here.
3519 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE.
3523 This is just another way to specify the start address of
3524 the flash sector containing the environment (instead of
3527 - CONFIG_ENV_SECT_SIZE:
3529 Size of the sector containing the environment.
3532 b) Sometimes flash chips have few, equal sized, BIG sectors.
3533 In such a case you don't want to spend a whole sector for
3538 If you use this in combination with CONFIG_ENV_IS_IN_FLASH
3539 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part
3540 of this flash sector for the environment. This saves
3541 memory for the RAM copy of the environment.
3543 It may also save flash memory if you decide to use this
3544 when your environment is "embedded" within U-Boot code,
3545 since then the remainder of the flash sector could be used
3546 for U-Boot code. It should be pointed out that this is
3547 STRONGLY DISCOURAGED from a robustness point of view:
3548 updating the environment in flash makes it always
3549 necessary to erase the WHOLE sector. If something goes
3550 wrong before the contents has been restored from a copy in
3551 RAM, your target system will be dead.
3553 - CONFIG_ENV_ADDR_REDUND
3554 CONFIG_ENV_SIZE_REDUND
3556 These settings describe a second storage area used to hold
3557 a redundant copy of the environment data, so that there is
3558 a valid backup copy in case there is a power failure during
3559 a "saveenv" operation.
3561 BE CAREFUL! Any changes to the flash layout, and some changes to the
3562 source code will make it necessary to adapt <board>/u-boot.lds*
3566 - CONFIG_ENV_IS_IN_NVRAM:
3568 Define this if you have some non-volatile memory device
3569 (NVRAM, battery buffered SRAM) which you want to use for the
3575 These two #defines are used to determine the memory area you
3576 want to use for environment. It is assumed that this memory
3577 can just be read and written to, without any special
3580 BE CAREFUL! The first access to the environment happens quite early
3581 in U-Boot initalization (when we try to get the setting of for the
3582 console baudrate). You *MUST* have mapped your NVRAM area then, or
3585 Please note that even with NVRAM we still use a copy of the
3586 environment in RAM: we could work on NVRAM directly, but we want to
3587 keep settings there always unmodified except somebody uses "saveenv"
3588 to save the current settings.
3591 - CONFIG_ENV_IS_IN_EEPROM:
3593 Use this if you have an EEPROM or similar serial access
3594 device and a driver for it.
3596 - CONFIG_ENV_OFFSET:
3599 These two #defines specify the offset and size of the
3600 environment area within the total memory of your EEPROM.
3602 - CONFIG_SYS_I2C_EEPROM_ADDR:
3603 If defined, specified the chip address of the EEPROM device.
3604 The default address is zero.
3606 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS:
3607 If defined, the number of bits used to address bytes in a
3608 single page in the EEPROM device. A 64 byte page, for example
3609 would require six bits.
3611 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS:
3612 If defined, the number of milliseconds to delay between
3613 page writes. The default is zero milliseconds.
3615 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN:
3616 The length in bytes of the EEPROM memory array address. Note
3617 that this is NOT the chip address length!
3619 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW:
3620 EEPROM chips that implement "address overflow" are ones
3621 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
3622 address and the extra bits end up in the "chip address" bit
3623 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
3626 Note that we consider the length of the address field to
3627 still be one byte because the extra address bits are hidden
3628 in the chip address.
3630 - CONFIG_SYS_EEPROM_SIZE:
3631 The size in bytes of the EEPROM device.
3633 - CONFIG_ENV_EEPROM_IS_ON_I2C
3634 define this, if you have I2C and SPI activated, and your
3635 EEPROM, which holds the environment, is on the I2C bus.
3637 - CONFIG_I2C_ENV_EEPROM_BUS
3638 if you have an Environment on an EEPROM reached over
3639 I2C muxes, you can define here, how to reach this
3640 EEPROM. For example:
3642 #define CONFIG_I2C_ENV_EEPROM_BUS 1
3644 EEPROM which holds the environment, is reached over
3645 a pca9547 i2c mux with address 0x70, channel 3.
3647 - CONFIG_ENV_IS_IN_DATAFLASH:
3649 Define this if you have a DataFlash memory device which you
3650 want to use for the environment.
3652 - CONFIG_ENV_OFFSET:
3656 These three #defines specify the offset and size of the
3657 environment area within the total memory of your DataFlash placed
3658 at the specified address.
3660 - CONFIG_ENV_IS_IN_REMOTE:
3662 Define this if you have a remote memory space which you
3663 want to use for the local device's environment.
3668 These two #defines specify the address and size of the
3669 environment area within the remote memory space. The
3670 local device can get the environment from remote memory
3671 space by SRIO or PCIE links.
3673 BE CAREFUL! For some special cases, the local device can not use
3674 "saveenv" command. For example, the local device will get the
3675 environment stored in a remote NOR flash by SRIO or PCIE link,
3676 but it can not erase, write this NOR flash by SRIO or PCIE interface.
3678 - CONFIG_ENV_IS_IN_NAND:
3680 Define this if you have a NAND device which you want to use
3681 for the environment.
3683 - CONFIG_ENV_OFFSET:
3686 These two #defines specify the offset and size of the environment
3687 area within the first NAND device. CONFIG_ENV_OFFSET must be
3688 aligned to an erase block boundary.
3690 - CONFIG_ENV_OFFSET_REDUND (optional):
3692 This setting describes a second storage area of CONFIG_ENV_SIZE
3693 size used to hold a redundant copy of the environment data, so
3694 that there is a valid backup copy in case there is a power failure
3695 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be
3696 aligned to an erase block boundary.
3698 - CONFIG_ENV_RANGE (optional):
3700 Specifies the length of the region in which the environment
3701 can be written. This should be a multiple of the NAND device's
3702 block size. Specifying a range with more erase blocks than
3703 are needed to hold CONFIG_ENV_SIZE allows bad blocks within
3704 the range to be avoided.
3706 - CONFIG_ENV_OFFSET_OOB (optional):
3708 Enables support for dynamically retrieving the offset of the
3709 environment from block zero's out-of-band data. The
3710 "nand env.oob" command can be used to record this offset.
3711 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when
3712 using CONFIG_ENV_OFFSET_OOB.
3714 - CONFIG_NAND_ENV_DST
3716 Defines address in RAM to which the nand_spl code should copy the
3717 environment. If redundant environment is used, it will be copied to
3718 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
3720 - CONFIG_ENV_IS_IN_UBI:
3722 Define this if you have an UBI volume that you want to use for the
3723 environment. This has the benefit of wear-leveling the environment
3724 accesses, which is important on NAND.
3726 - CONFIG_ENV_UBI_PART:
3728 Define this to a string that is the mtd partition containing the UBI.
3730 - CONFIG_ENV_UBI_VOLUME:
3732 Define this to the name of the volume that you want to store the
3735 - CONFIG_ENV_UBI_VOLUME_REDUND:
3737 Define this to the name of another volume to store a second copy of
3738 the environment in. This will enable redundant environments in UBI.
3739 It is assumed that both volumes are in the same MTD partition.
3741 - CONFIG_UBI_SILENCE_MSG
3742 - CONFIG_UBIFS_SILENCE_MSG
3744 You will probably want to define these to avoid a really noisy system
3745 when storing the env in UBI.
3747 - CONFIG_ENV_IS_IN_MMC:
3749 Define this if you have an MMC device which you want to use for the
3752 - CONFIG_SYS_MMC_ENV_DEV:
3754 Specifies which MMC device the environment is stored in.
3756 - CONFIG_SYS_MMC_ENV_PART (optional):
3758 Specifies which MMC partition the environment is stored in. If not
3759 set, defaults to partition 0, the user area. Common values might be
3760 1 (first MMC boot partition), 2 (second MMC boot partition).
3762 - CONFIG_ENV_OFFSET:
3765 These two #defines specify the offset and size of the environment
3766 area within the specified MMC device.
3768 If offset is positive (the usual case), it is treated as relative to
3769 the start of the MMC partition. If offset is negative, it is treated
3770 as relative to the end of the MMC partition. This can be useful if
3771 your board may be fitted with different MMC devices, which have
3772 different sizes for the MMC partitions, and you always want the
3773 environment placed at the very end of the partition, to leave the
3774 maximum possible space before it, to store other data.
3776 These two values are in units of bytes, but must be aligned to an
3777 MMC sector boundary.
3779 - CONFIG_ENV_OFFSET_REDUND (optional):
3781 Specifies a second storage area, of CONFIG_ENV_SIZE size, used to
3782 hold a redundant copy of the environment data. This provides a
3783 valid backup copy in case the other copy is corrupted, e.g. due
3784 to a power failure during a "saveenv" operation.
3786 This value may also be positive or negative; this is handled in the
3787 same way as CONFIG_ENV_OFFSET.
3789 This value is also in units of bytes, but must also be aligned to
3790 an MMC sector boundary.
3792 - CONFIG_ENV_SIZE_REDUND (optional):
3794 This value need not be set, even when CONFIG_ENV_OFFSET_REDUND is
3795 set. If this value is set, it must be set to the same value as
3798 - CONFIG_SYS_SPI_INIT_OFFSET
3800 Defines offset to the initial SPI buffer area in DPRAM. The
3801 area is used at an early stage (ROM part) if the environment
3802 is configured to reside in the SPI EEPROM: We need a 520 byte
3803 scratch DPRAM area. It is used between the two initialization
3804 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
3805 to be a good choice since it makes it far enough from the
3806 start of the data area as well as from the stack pointer.
3808 Please note that the environment is read-only until the monitor
3809 has been relocated to RAM and a RAM copy of the environment has been
3810 created; also, when using EEPROM you will have to use getenv_f()
3811 until then to read environment variables.
3813 The environment is protected by a CRC32 checksum. Before the monitor
3814 is relocated into RAM, as a result of a bad CRC you will be working
3815 with the compiled-in default environment - *silently*!!! [This is
3816 necessary, because the first environment variable we need is the
3817 "baudrate" setting for the console - if we have a bad CRC, we don't
3818 have any device yet where we could complain.]
3820 Note: once the monitor has been relocated, then it will complain if
3821 the default environment is used; a new CRC is computed as soon as you
3822 use the "saveenv" command to store a valid environment.
3824 - CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
3825 Echo the inverted Ethernet link state to the fault LED.
3827 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
3828 also needs to be defined.
3830 - CONFIG_SYS_FAULT_MII_ADDR:
3831 MII address of the PHY to check for the Ethernet link state.
3833 - CONFIG_NS16550_MIN_FUNCTIONS:
3834 Define this if you desire to only have use of the NS16550_init
3835 and NS16550_putc functions for the serial driver located at
3836 drivers/serial/ns16550.c. This option is useful for saving
3837 space for already greatly restricted images, including but not
3838 limited to NAND_SPL configurations.
3840 - CONFIG_DISPLAY_BOARDINFO
3841 Display information about the board that U-Boot is running on
3842 when U-Boot starts up. The board function checkboard() is called
3845 - CONFIG_DISPLAY_BOARDINFO_LATE
3846 Similar to the previous option, but display this information
3847 later, once stdio is running and output goes to the LCD, if
3850 Low Level (hardware related) configuration options:
3851 ---------------------------------------------------
3853 - CONFIG_SYS_CACHELINE_SIZE:
3854 Cache Line Size of the CPU.
3856 - CONFIG_SYS_DEFAULT_IMMR:
3857 Default address of the IMMR after system reset.
3859 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
3860 and RPXsuper) to be able to adjust the position of
3861 the IMMR register after a reset.
3863 - CONFIG_SYS_CCSRBAR_DEFAULT:
3864 Default (power-on reset) physical address of CCSR on Freescale
3867 - CONFIG_SYS_CCSRBAR:
3868 Virtual address of CCSR. On a 32-bit build, this is typically
3869 the same value as CONFIG_SYS_CCSRBAR_DEFAULT.
3871 CONFIG_SYS_DEFAULT_IMMR must also be set to this value,
3872 for cross-platform code that uses that macro instead.
3874 - CONFIG_SYS_CCSRBAR_PHYS:
3875 Physical address of CCSR. CCSR can be relocated to a new
3876 physical address, if desired. In this case, this macro should
3877 be set to that address. Otherwise, it should be set to the
3878 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR
3879 is typically relocated on 36-bit builds. It is recommended
3880 that this macro be defined via the _HIGH and _LOW macros:
3882 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH
3883 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW)
3885 - CONFIG_SYS_CCSRBAR_PHYS_HIGH:
3886 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically
3887 either 0 (32-bit build) or 0xF (36-bit build). This macro is
3888 used in assembly code, so it must not contain typecasts or
3889 integer size suffixes (e.g. "ULL").
3891 - CONFIG_SYS_CCSRBAR_PHYS_LOW:
3892 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is
3893 used in assembly code, so it must not contain typecasts or
3894 integer size suffixes (e.g. "ULL").
3896 - CONFIG_SYS_CCSR_DO_NOT_RELOCATE:
3897 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be
3898 forced to a value that ensures that CCSR is not relocated.
3900 - Floppy Disk Support:
3901 CONFIG_SYS_FDC_DRIVE_NUMBER
3903 the default drive number (default value 0)
3905 CONFIG_SYS_ISA_IO_STRIDE
3907 defines the spacing between FDC chipset registers
3910 CONFIG_SYS_ISA_IO_OFFSET
3912 defines the offset of register from address. It
3913 depends on which part of the data bus is connected to
3914 the FDC chipset. (default value 0)
3916 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
3917 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
3920 if CONFIG_SYS_FDC_HW_INIT is defined, then the function
3921 fdc_hw_init() is called at the beginning of the FDC
3922 setup. fdc_hw_init() must be provided by the board
3923 source code. It is used to make hardware dependant
3927 Most IDE controllers were designed to be connected with PCI
3928 interface. Only few of them were designed for AHB interface.
3929 When software is doing ATA command and data transfer to
3930 IDE devices through IDE-AHB controller, some additional
3931 registers accessing to these kind of IDE-AHB controller
3934 - CONFIG_SYS_IMMR: Physical address of the Internal Memory.
3935 DO NOT CHANGE unless you know exactly what you're
3936 doing! (11-4) [MPC8xx/82xx systems only]
3938 - CONFIG_SYS_INIT_RAM_ADDR:
3940 Start address of memory area that can be used for
3941 initial data and stack; please note that this must be
3942 writable memory that is working WITHOUT special
3943 initialization, i. e. you CANNOT use normal RAM which
3944 will become available only after programming the
3945 memory controller and running certain initialization
3948 U-Boot uses the following memory types:
3949 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
3950 - MPC824X: data cache
3951 - PPC4xx: data cache
3953 - CONFIG_SYS_GBL_DATA_OFFSET:
3955 Offset of the initial data structure in the memory
3956 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
3957 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
3958 data is located at the end of the available space
3959 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
3960 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just
3961 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
3962 CONFIG_SYS_GBL_DATA_OFFSET) downward.
3965 On the MPC824X (or other systems that use the data
3966 cache for initial memory) the address chosen for
3967 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
3968 point to an otherwise UNUSED address space between
3969 the top of RAM and the start of the PCI space.
3971 - CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6)
3973 - CONFIG_SYS_SYPCR: System Protection Control (11-9)
3975 - CONFIG_SYS_TBSCR: Time Base Status and Control (11-26)
3977 - CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31)
3979 - CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
3981 - CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
3983 - CONFIG_SYS_OR_TIMING_SDRAM:
3986 - CONFIG_SYS_MAMR_PTA:
3987 periodic timer for refresh
3989 - CONFIG_SYS_DER: Debug Event Register (37-47)
3991 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
3992 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
3993 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
3994 CONFIG_SYS_BR1_PRELIM:
3995 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
3997 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
3998 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
3999 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
4000 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
4002 - CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K,
4003 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL:
4004 Machine Mode Register and Memory Periodic Timer
4005 Prescaler definitions (SDRAM timing)
4007 - CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]:
4008 enable I2C microcode relocation patch (MPC8xx);
4009 define relocation offset in DPRAM [DSP2]
4011 - CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]:
4012 enable SMC microcode relocation patch (MPC8xx);
4013 define relocation offset in DPRAM [SMC1]
4015 - CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]:
4016 enable SPI microcode relocation patch (MPC8xx);
4017 define relocation offset in DPRAM [SCC4]
4019 - CONFIG_SYS_USE_OSCCLK:
4020 Use OSCM clock mode on MBX8xx board. Be careful,
4021 wrong setting might damage your board. Read
4022 doc/README.MBX before setting this variable!
4024 - CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
4025 Offset of the bootmode word in DPRAM used by post
4026 (Power On Self Tests). This definition overrides
4027 #define'd default value in commproc.h resp.
4030 - CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB,
4031 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL,
4032 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS,
4033 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB,
4034 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
4035 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL,
4036 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE,
4037 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only)
4038 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set.
4040 - CONFIG_PCI_DISABLE_PCIE:
4041 Disable PCI-Express on systems where it is supported but not
4044 - CONFIG_PCI_ENUM_ONLY
4045 Only scan through and get the devices on the busses.
4046 Don't do any setup work, presumably because someone or
4047 something has already done it, and we don't need to do it
4048 a second time. Useful for platforms that are pre-booted
4049 by coreboot or similar.
4051 - CONFIG_PCI_INDIRECT_BRIDGE:
4052 Enable support for indirect PCI bridges.
4055 Chip has SRIO or not
4058 Board has SRIO 1 port available
4061 Board has SRIO 2 port available
4063 - CONFIG_SRIO_PCIE_BOOT_MASTER
4064 Board can support master function for Boot from SRIO and PCIE
4066 - CONFIG_SYS_SRIOn_MEM_VIRT:
4067 Virtual Address of SRIO port 'n' memory region
4069 - CONFIG_SYS_SRIOn_MEM_PHYS:
4070 Physical Address of SRIO port 'n' memory region
4072 - CONFIG_SYS_SRIOn_MEM_SIZE:
4073 Size of SRIO port 'n' memory region
4075 - CONFIG_SYS_NAND_BUSWIDTH_16BIT
4076 Defined to tell the NAND controller that the NAND chip is using
4078 Not all NAND drivers use this symbol.
4079 Example of drivers that use it:
4080 - drivers/mtd/nand/ndfc.c
4081 - drivers/mtd/nand/mxc_nand.c
4083 - CONFIG_SYS_NDFC_EBC0_CFG
4084 Sets the EBC0_CFG register for the NDFC. If not defined
4085 a default value will be used.
4088 Get DDR timing information from an I2C EEPROM. Common
4089 with pluggable memory modules such as SODIMMs
4092 I2C address of the SPD EEPROM
4094 - CONFIG_SYS_SPD_BUS_NUM
4095 If SPD EEPROM is on an I2C bus other than the first
4096 one, specify here. Note that the value must resolve
4097 to something your driver can deal with.
4099 - CONFIG_SYS_DDR_RAW_TIMING
4100 Get DDR timing information from other than SPD. Common with
4101 soldered DDR chips onboard without SPD. DDR raw timing
4102 parameters are extracted from datasheet and hard-coded into
4103 header files or board specific files.
4105 - CONFIG_FSL_DDR_INTERACTIVE
4106 Enable interactive DDR debugging. See doc/README.fsl-ddr.
4108 - CONFIG_SYS_83XX_DDR_USES_CS0
4109 Only for 83xx systems. If specified, then DDR should
4110 be configured using CS0 and CS1 instead of CS2 and CS3.
4112 - CONFIG_ETHER_ON_FEC[12]
4113 Define to enable FEC[12] on a 8xx series processor.
4115 - CONFIG_FEC[12]_PHY
4116 Define to the hardcoded PHY address which corresponds
4117 to the given FEC; i. e.
4118 #define CONFIG_FEC1_PHY 4
4119 means that the PHY with address 4 is connected to FEC1
4121 When set to -1, means to probe for first available.
4123 - CONFIG_FEC[12]_PHY_NORXERR
4124 The PHY does not have a RXERR line (RMII only).
4125 (so program the FEC to ignore it).
4128 Enable RMII mode for all FECs.
4129 Note that this is a global option, we can't
4130 have one FEC in standard MII mode and another in RMII mode.
4132 - CONFIG_CRC32_VERIFY
4133 Add a verify option to the crc32 command.
4136 => crc32 -v <address> <count> <crc32>
4138 Where address/count indicate a memory area
4139 and crc32 is the correct crc32 which the
4143 Add the "loopw" memory command. This only takes effect if
4144 the memory commands are activated globally (CONFIG_CMD_MEM).
4147 Add the "mdc" and "mwc" memory commands. These are cyclic
4152 This command will print 4 bytes (10,11,12,13) each 500 ms.
4154 => mwc.l 100 12345678 10
4155 This command will write 12345678 to address 100 all 10 ms.
4157 This only takes effect if the memory commands are activated
4158 globally (CONFIG_CMD_MEM).
4160 - CONFIG_SKIP_LOWLEVEL_INIT
4161 [ARM, NDS32, MIPS only] If this variable is defined, then certain
4162 low level initializations (like setting up the memory
4163 controller) are omitted and/or U-Boot does not
4164 relocate itself into RAM.
4166 Normally this variable MUST NOT be defined. The only
4167 exception is when U-Boot is loaded (to RAM) by some
4168 other boot loader or by a debugger which performs
4169 these initializations itself.
4172 Modifies the behaviour of start.S when compiling a loader
4173 that is executed before the actual U-Boot. E.g. when
4174 compiling a NAND SPL.
4176 - CONFIG_SYS_MPC85XX_NO_RESETVEC
4177 Only for 85xx systems. If this variable is specified, the section
4178 .resetvec is not kept and the section .bootpg is placed in the
4179 previous 4k of the .text section.
4181 - CONFIG_ARCH_MAP_SYSMEM
4182 Generally U-Boot (and in particular the md command) uses
4183 effective address. It is therefore not necessary to regard
4184 U-Boot address as virtual addresses that need to be translated
4185 to physical addresses. However, sandbox requires this, since
4186 it maintains its own little RAM buffer which contains all
4187 addressable memory. This option causes some memory accesses
4188 to be mapped through map_sysmem() / unmap_sysmem().
4190 - CONFIG_USE_ARCH_MEMCPY
4191 CONFIG_USE_ARCH_MEMSET
4192 If these options are used a optimized version of memcpy/memset will
4193 be used if available. These functions may be faster under some
4194 conditions but may increase the binary size.
4196 - CONFIG_X86_RESET_VECTOR
4197 If defined, the x86 reset vector code is included. This is not
4198 needed when U-Boot is running from Coreboot.
4201 Defines the MPU clock speed (in MHz).
4203 NOTE : currently only supported on AM335x platforms.
4205 Freescale QE/FMAN Firmware Support:
4206 -----------------------------------
4208 The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
4209 loading of "firmware", which is encoded in the QE firmware binary format.
4210 This firmware often needs to be loaded during U-Boot booting, so macros
4211 are used to identify the storage device (NOR flash, SPI, etc) and the address
4214 - CONFIG_SYS_QE_FMAN_FW_ADDR
4215 The address in the storage device where the firmware is located. The
4216 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
4219 - CONFIG_SYS_QE_FMAN_FW_LENGTH
4220 The maximum possible size of the firmware. The firmware binary format
4221 has a field that specifies the actual size of the firmware, but it
4222 might not be possible to read any part of the firmware unless some
4223 local storage is allocated to hold the entire firmware first.
4225 - CONFIG_SYS_QE_FMAN_FW_IN_NOR
4226 Specifies that QE/FMAN firmware is located in NOR flash, mapped as
4227 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the
4228 virtual address in NOR flash.
4230 - CONFIG_SYS_QE_FMAN_FW_IN_NAND
4231 Specifies that QE/FMAN firmware is located in NAND flash.
4232 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.
4234 - CONFIG_SYS_QE_FMAN_FW_IN_MMC
4235 Specifies that QE/FMAN firmware is located on the primary SD/MMC
4236 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
4238 - CONFIG_SYS_QE_FMAN_FW_IN_SPIFLASH
4239 Specifies that QE/FMAN firmware is located on the primary SPI
4240 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
4242 - CONFIG_SYS_QE_FMAN_FW_IN_REMOTE
4243 Specifies that QE/FMAN firmware is located in the remote (master)
4244 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which
4245 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound
4246 window->master inbound window->master LAW->the ucode address in
4247 master's memory space.
4249 Building the Software:
4250 ======================
4252 Building U-Boot has been tested in several native build environments
4253 and in many different cross environments. Of course we cannot support
4254 all possibly existing versions of cross development tools in all
4255 (potentially obsolete) versions. In case of tool chain problems we
4256 recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
4257 which is extensively used to build and test U-Boot.
4259 If you are not using a native environment, it is assumed that you
4260 have GNU cross compiling tools available in your path. In this case,
4261 you must set the environment variable CROSS_COMPILE in your shell.
4262 Note that no changes to the Makefile or any other source files are
4263 necessary. For example using the ELDK on a 4xx CPU, please enter:
4265 $ CROSS_COMPILE=ppc_4xx-
4266 $ export CROSS_COMPILE
4268 Note: If you wish to generate Windows versions of the utilities in
4269 the tools directory you can use the MinGW toolchain
4270 (http://www.mingw.org). Set your HOST tools to the MinGW
4271 toolchain and execute 'make tools'. For example:
4273 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
4275 Binaries such as tools/mkimage.exe will be created which can
4276 be executed on computers running Windows.
4278 U-Boot is intended to be simple to build. After installing the
4279 sources you must configure U-Boot for one specific board type. This
4284 where "NAME_config" is the name of one of the existing configu-
4285 rations; see boards.cfg for supported names.
4287 Note: for some board special configuration names may exist; check if
4288 additional information is available from the board vendor; for
4289 instance, the TQM823L systems are available without (standard)
4290 or with LCD support. You can select such additional "features"
4291 when choosing the configuration, i. e.
4294 - will configure for a plain TQM823L, i. e. no LCD support
4296 make TQM823L_LCD_config
4297 - will configure for a TQM823L with U-Boot console on LCD
4302 Finally, type "make all", and you should get some working U-Boot
4303 images ready for download to / installation on your system:
4305 - "u-boot.bin" is a raw binary image
4306 - "u-boot" is an image in ELF binary format
4307 - "u-boot.srec" is in Motorola S-Record format
4309 By default the build is performed locally and the objects are saved
4310 in the source directory. One of the two methods can be used to change
4311 this behavior and build U-Boot to some external directory:
4313 1. Add O= to the make command line invocations:
4315 make O=/tmp/build distclean
4316 make O=/tmp/build NAME_config
4317 make O=/tmp/build all
4319 2. Set environment variable BUILD_DIR to point to the desired location:
4321 export BUILD_DIR=/tmp/build
4326 Note that the command line "O=" setting overrides the BUILD_DIR environment
4330 Please be aware that the Makefiles assume you are using GNU make, so
4331 for instance on NetBSD you might need to use "gmake" instead of
4335 If the system board that you have is not listed, then you will need
4336 to port U-Boot to your hardware platform. To do this, follow these
4339 1. Add a new configuration option for your board to the toplevel
4340 "boards.cfg" file, using the existing entries as examples.
4341 Follow the instructions there to keep the boards in order.
4342 2. Create a new directory to hold your board specific code. Add any
4343 files you need. In your board directory, you will need at least
4344 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
4345 3. Create a new configuration file "include/configs/<board>.h" for
4347 3. If you're porting U-Boot to a new CPU, then also create a new
4348 directory to hold your CPU specific code. Add any files you need.
4349 4. Run "make <board>_config" with your new name.
4350 5. Type "make", and you should get a working "u-boot.srec" file
4351 to be installed on your target system.
4352 6. Debug and solve any problems that might arise.
4353 [Of course, this last step is much harder than it sounds.]
4356 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
4357 ==============================================================
4359 If you have modified U-Boot sources (for instance added a new board
4360 or support for new devices, a new CPU, etc.) you are expected to
4361 provide feedback to the other developers. The feedback normally takes
4362 the form of a "patch", i. e. a context diff against a certain (latest
4363 official or latest in the git repository) version of U-Boot sources.
4365 But before you submit such a patch, please verify that your modifi-
4366 cation did not break existing code. At least make sure that *ALL* of
4367 the supported boards compile WITHOUT ANY compiler warnings. To do so,
4368 just run the "MAKEALL" script, which will configure and build U-Boot
4369 for ALL supported system. Be warned, this will take a while. You can
4370 select which (cross) compiler to use by passing a `CROSS_COMPILE'
4371 environment variable to the script, i. e. to use the ELDK cross tools
4374 CROSS_COMPILE=ppc_8xx- MAKEALL
4376 or to build on a native PowerPC system you can type
4378 CROSS_COMPILE=' ' MAKEALL
4380 When using the MAKEALL script, the default behaviour is to build
4381 U-Boot in the source directory. This location can be changed by
4382 setting the BUILD_DIR environment variable. Also, for each target
4383 built, the MAKEALL script saves two log files (<target>.ERR and
4384 <target>.MAKEALL) in the <source dir>/LOG directory. This default
4385 location can be changed by setting the MAKEALL_LOGDIR environment
4386 variable. For example:
4388 export BUILD_DIR=/tmp/build
4389 export MAKEALL_LOGDIR=/tmp/log
4390 CROSS_COMPILE=ppc_8xx- MAKEALL
4392 With the above settings build objects are saved in the /tmp/build,
4393 log files are saved in the /tmp/log and the source tree remains clean
4394 during the whole build process.
4397 See also "U-Boot Porting Guide" below.
4400 Monitor Commands - Overview:
4401 ============================
4403 go - start application at address 'addr'
4404 run - run commands in an environment variable
4405 bootm - boot application image from memory
4406 bootp - boot image via network using BootP/TFTP protocol
4407 bootz - boot zImage from memory
4408 tftpboot- boot image via network using TFTP protocol
4409 and env variables "ipaddr" and "serverip"
4410 (and eventually "gatewayip")
4411 tftpput - upload a file via network using TFTP protocol
4412 rarpboot- boot image via network using RARP/TFTP protocol
4413 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
4414 loads - load S-Record file over serial line
4415 loadb - load binary file over serial line (kermit mode)
4417 mm - memory modify (auto-incrementing)
4418 nm - memory modify (constant address)
4419 mw - memory write (fill)
4421 cmp - memory compare
4422 crc32 - checksum calculation
4423 i2c - I2C sub-system
4424 sspi - SPI utility commands
4425 base - print or set address offset
4426 printenv- print environment variables
4427 setenv - set environment variables
4428 saveenv - save environment variables to persistent storage
4429 protect - enable or disable FLASH write protection
4430 erase - erase FLASH memory
4431 flinfo - print FLASH memory information
4432 nand - NAND memory operations (see doc/README.nand)
4433 bdinfo - print Board Info structure
4434 iminfo - print header information for application image
4435 coninfo - print console devices and informations
4436 ide - IDE sub-system
4437 loop - infinite loop on address range
4438 loopw - infinite write loop on address range
4439 mtest - simple RAM test
4440 icache - enable or disable instruction cache
4441 dcache - enable or disable data cache
4442 reset - Perform RESET of the CPU
4443 echo - echo args to console
4444 version - print monitor version
4445 help - print online help
4446 ? - alias for 'help'
4449 Monitor Commands - Detailed Description:
4450 ========================================
4454 For now: just type "help <command>".
4457 Environment Variables:
4458 ======================
4460 U-Boot supports user configuration using Environment Variables which
4461 can be made persistent by saving to Flash memory.
4463 Environment Variables are set using "setenv", printed using
4464 "printenv", and saved to Flash using "saveenv". Using "setenv"
4465 without a value can be used to delete a variable from the
4466 environment. As long as you don't save the environment you are
4467 working with an in-memory copy. In case the Flash area containing the
4468 environment is erased by accident, a default environment is provided.
4470 Some configuration options can be set using Environment Variables.
4472 List of environment variables (most likely not complete):
4474 baudrate - see CONFIG_BAUDRATE
4476 bootdelay - see CONFIG_BOOTDELAY
4478 bootcmd - see CONFIG_BOOTCOMMAND
4480 bootargs - Boot arguments when booting an RTOS image
4482 bootfile - Name of the image to load with TFTP
4484 bootm_low - Memory range available for image processing in the bootm
4485 command can be restricted. This variable is given as
4486 a hexadecimal number and defines lowest address allowed
4487 for use by the bootm command. See also "bootm_size"
4488 environment variable. Address defined by "bootm_low" is
4489 also the base of the initial memory mapping for the Linux
4490 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
4493 bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
4494 This variable is given as a hexadecimal number and it
4495 defines the size of the memory region starting at base
4496 address bootm_low that is accessible by the Linux kernel
4497 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used
4498 as the default value if it is defined, and bootm_size is
4501 bootm_size - Memory range available for image processing in the bootm
4502 command can be restricted. This variable is given as
4503 a hexadecimal number and defines the size of the region
4504 allowed for use by the bootm command. See also "bootm_low"
4505 environment variable.
4507 updatefile - Location of the software update file on a TFTP server, used
4508 by the automatic software update feature. Please refer to
4509 documentation in doc/README.update for more details.
4511 autoload - if set to "no" (any string beginning with 'n'),
4512 "bootp" will just load perform a lookup of the
4513 configuration from the BOOTP server, but not try to
4514 load any image using TFTP
4516 autostart - if set to "yes", an image loaded using the "bootp",
4517 "rarpboot", "tftpboot" or "diskboot" commands will
4518 be automatically started (by internally calling
4521 If set to "no", a standalone image passed to the
4522 "bootm" command will be copied to the load address
4523 (and eventually uncompressed), but NOT be started.
4524 This can be used to load and uncompress arbitrary
4527 fdt_high - if set this restricts the maximum address that the
4528 flattened device tree will be copied into upon boot.
4529 For example, if you have a system with 1 GB memory
4530 at physical address 0x10000000, while Linux kernel
4531 only recognizes the first 704 MB as low memory, you
4532 may need to set fdt_high as 0x3C000000 to have the
4533 device tree blob be copied to the maximum address
4534 of the 704 MB low memory, so that Linux kernel can
4535 access it during the boot procedure.
4537 If this is set to the special value 0xFFFFFFFF then
4538 the fdt will not be copied at all on boot. For this
4539 to work it must reside in writable memory, have
4540 sufficient padding on the end of it for u-boot to
4541 add the information it needs into it, and the memory
4542 must be accessible by the kernel.
4544 fdtcontroladdr- if set this is the address of the control flattened
4545 device tree used by U-Boot when CONFIG_OF_CONTROL is
4548 i2cfast - (PPC405GP|PPC405EP only)
4549 if set to 'y' configures Linux I2C driver for fast
4550 mode (400kHZ). This environment variable is used in
4551 initialization code. So, for changes to be effective
4552 it must be saved and board must be reset.
4554 initrd_high - restrict positioning of initrd images:
4555 If this variable is not set, initrd images will be
4556 copied to the highest possible address in RAM; this
4557 is usually what you want since it allows for
4558 maximum initrd size. If for some reason you want to
4559 make sure that the initrd image is loaded below the
4560 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
4561 variable to a value of "no" or "off" or "0".
4562 Alternatively, you can set it to a maximum upper
4563 address to use (U-Boot will still check that it
4564 does not overwrite the U-Boot stack and data).
4566 For instance, when you have a system with 16 MB
4567 RAM, and want to reserve 4 MB from use by Linux,
4568 you can do this by adding "mem=12M" to the value of
4569 the "bootargs" variable. However, now you must make
4570 sure that the initrd image is placed in the first
4571 12 MB as well - this can be done with
4573 setenv initrd_high 00c00000
4575 If you set initrd_high to 0xFFFFFFFF, this is an
4576 indication to U-Boot that all addresses are legal
4577 for the Linux kernel, including addresses in flash
4578 memory. In this case U-Boot will NOT COPY the
4579 ramdisk at all. This may be useful to reduce the
4580 boot time on your system, but requires that this
4581 feature is supported by your Linux kernel.
4583 ipaddr - IP address; needed for tftpboot command
4585 loadaddr - Default load address for commands like "bootp",
4586 "rarpboot", "tftpboot", "loadb" or "diskboot"
4588 loads_echo - see CONFIG_LOADS_ECHO
4590 serverip - TFTP server IP address; needed for tftpboot command
4592 bootretry - see CONFIG_BOOT_RETRY_TIME
4594 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
4596 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
4598 ethprime - controls which interface is used first.
4600 ethact - controls which interface is currently active.
4601 For example you can do the following
4603 => setenv ethact FEC
4604 => ping 192.168.0.1 # traffic sent on FEC
4605 => setenv ethact SCC
4606 => ping 10.0.0.1 # traffic sent on SCC
4608 ethrotate - When set to "no" U-Boot does not go through all
4609 available network interfaces.
4610 It just stays at the currently selected interface.
4612 netretry - When set to "no" each network operation will
4613 either succeed or fail without retrying.
4614 When set to "once" the network operation will
4615 fail when all the available network interfaces
4616 are tried once without success.
4617 Useful on scripts which control the retry operation
4620 npe_ucode - set load address for the NPE microcode
4622 tftpsrcport - If this is set, the value is used for TFTP's
4625 tftpdstport - If this is set, the value is used for TFTP's UDP
4626 destination port instead of the Well Know Port 69.
4628 tftpblocksize - Block size to use for TFTP transfers; if not set,
4629 we use the TFTP server's default block size
4631 tftptimeout - Retransmission timeout for TFTP packets (in milli-
4632 seconds, minimum value is 1000 = 1 second). Defines
4633 when a packet is considered to be lost so it has to
4634 be retransmitted. The default is 5000 = 5 seconds.
4635 Lowering this value may make downloads succeed
4636 faster in networks with high packet loss rates or
4637 with unreliable TFTP servers.
4639 vlan - When set to a value < 4095 the traffic over
4640 Ethernet is encapsulated/received over 802.1q
4643 The following image location variables contain the location of images
4644 used in booting. The "Image" column gives the role of the image and is
4645 not an environment variable name. The other columns are environment
4646 variable names. "File Name" gives the name of the file on a TFTP
4647 server, "RAM Address" gives the location in RAM the image will be
4648 loaded to, and "Flash Location" gives the image's address in NOR
4649 flash or offset in NAND flash.
4651 *Note* - these variables don't have to be defined for all boards, some
4652 boards currenlty use other variables for these purposes, and some
4653 boards use these variables for other purposes.
4655 Image File Name RAM Address Flash Location
4656 ----- --------- ----------- --------------
4657 u-boot u-boot u-boot_addr_r u-boot_addr
4658 Linux kernel bootfile kernel_addr_r kernel_addr
4659 device tree blob fdtfile fdt_addr_r fdt_addr
4660 ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr
4662 The following environment variables may be used and automatically
4663 updated by the network boot commands ("bootp" and "rarpboot"),
4664 depending the information provided by your boot server:
4666 bootfile - see above
4667 dnsip - IP address of your Domain Name Server
4668 dnsip2 - IP address of your secondary Domain Name Server
4669 gatewayip - IP address of the Gateway (Router) to use
4670 hostname - Target hostname
4672 netmask - Subnet Mask
4673 rootpath - Pathname of the root filesystem on the NFS server
4674 serverip - see above
4677 There are two special Environment Variables:
4679 serial# - contains hardware identification information such
4680 as type string and/or serial number
4681 ethaddr - Ethernet address
4683 These variables can be set only once (usually during manufacturing of
4684 the board). U-Boot refuses to delete or overwrite these variables
4685 once they have been set once.
4688 Further special Environment Variables:
4690 ver - Contains the U-Boot version string as printed
4691 with the "version" command. This variable is
4692 readonly (see CONFIG_VERSION_VARIABLE).
4695 Please note that changes to some configuration parameters may take
4696 only effect after the next boot (yes, that's just like Windoze :-).
4699 Callback functions for environment variables:
4700 ---------------------------------------------
4702 For some environment variables, the behavior of u-boot needs to change
4703 when their values are changed. This functionailty allows functions to
4704 be associated with arbitrary variables. On creation, overwrite, or
4705 deletion, the callback will provide the opportunity for some side
4706 effect to happen or for the change to be rejected.
4708 The callbacks are named and associated with a function using the
4709 U_BOOT_ENV_CALLBACK macro in your board or driver code.
4711 These callbacks are associated with variables in one of two ways. The
4712 static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC
4713 in the board configuration to a string that defines a list of
4714 associations. The list must be in the following format:
4716 entry = variable_name[:callback_name]
4719 If the callback name is not specified, then the callback is deleted.
4720 Spaces are also allowed anywhere in the list.
4722 Callbacks can also be associated by defining the ".callbacks" variable
4723 with the same list format above. Any association in ".callbacks" will
4724 override any association in the static list. You can define
4725 CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the
4726 ".callbacks" envirnoment variable in the default or embedded environment.
4729 Command Line Parsing:
4730 =====================
4732 There are two different command line parsers available with U-Boot:
4733 the old "simple" one, and the much more powerful "hush" shell:
4735 Old, simple command line parser:
4736 --------------------------------
4738 - supports environment variables (through setenv / saveenv commands)
4739 - several commands on one line, separated by ';'
4740 - variable substitution using "... ${name} ..." syntax
4741 - special characters ('$', ';') can be escaped by prefixing with '\',
4743 setenv bootcmd bootm \${address}
4744 - You can also escape text by enclosing in single apostrophes, for example:
4745 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
4750 - similar to Bourne shell, with control structures like
4751 if...then...else...fi, for...do...done; while...do...done,
4752 until...do...done, ...
4753 - supports environment ("global") variables (through setenv / saveenv
4754 commands) and local shell variables (through standard shell syntax
4755 "name=value"); only environment variables can be used with "run"
4761 (1) If a command line (or an environment variable executed by a "run"
4762 command) contains several commands separated by semicolon, and
4763 one of these commands fails, then the remaining commands will be
4766 (2) If you execute several variables with one call to run (i. e.
4767 calling run with a list of variables as arguments), any failing
4768 command will cause "run" to terminate, i. e. the remaining
4769 variables are not executed.
4771 Note for Redundant Ethernet Interfaces:
4772 =======================================
4774 Some boards come with redundant Ethernet interfaces; U-Boot supports
4775 such configurations and is capable of automatic selection of a
4776 "working" interface when needed. MAC assignment works as follows:
4778 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
4779 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
4780 "eth1addr" (=>eth1), "eth2addr", ...
4782 If the network interface stores some valid MAC address (for instance
4783 in SROM), this is used as default address if there is NO correspon-
4784 ding setting in the environment; if the corresponding environment
4785 variable is set, this overrides the settings in the card; that means:
4787 o If the SROM has a valid MAC address, and there is no address in the
4788 environment, the SROM's address is used.
4790 o If there is no valid address in the SROM, and a definition in the
4791 environment exists, then the value from the environment variable is
4794 o If both the SROM and the environment contain a MAC address, and
4795 both addresses are the same, this MAC address is used.
4797 o If both the SROM and the environment contain a MAC address, and the
4798 addresses differ, the value from the environment is used and a
4801 o If neither SROM nor the environment contain a MAC address, an error
4804 If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
4805 will be programmed into hardware as part of the initialization process. This
4806 may be skipped by setting the appropriate 'ethmacskip' environment variable.
4807 The naming convention is as follows:
4808 "ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
4813 U-Boot is capable of booting (and performing other auxiliary operations on)
4814 images in two formats:
4816 New uImage format (FIT)
4817 -----------------------
4819 Flexible and powerful format based on Flattened Image Tree -- FIT (similar
4820 to Flattened Device Tree). It allows the use of images with multiple
4821 components (several kernels, ramdisks, etc.), with contents protected by
4822 SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
4828 Old image format is based on binary files which can be basically anything,
4829 preceded by a special header; see the definitions in include/image.h for
4830 details; basically, the header defines the following image properties:
4832 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
4833 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
4834 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
4835 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
4837 * Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86,
4838 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
4839 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC).
4840 * Compression Type (uncompressed, gzip, bzip2)
4846 The header is marked by a special Magic Number, and both the header
4847 and the data portions of the image are secured against corruption by
4854 Although U-Boot should support any OS or standalone application
4855 easily, the main focus has always been on Linux during the design of
4858 U-Boot includes many features that so far have been part of some
4859 special "boot loader" code within the Linux kernel. Also, any
4860 "initrd" images to be used are no longer part of one big Linux image;
4861 instead, kernel and "initrd" are separate images. This implementation
4862 serves several purposes:
4864 - the same features can be used for other OS or standalone
4865 applications (for instance: using compressed images to reduce the
4866 Flash memory footprint)
4868 - it becomes much easier to port new Linux kernel versions because
4869 lots of low-level, hardware dependent stuff are done by U-Boot
4871 - the same Linux kernel image can now be used with different "initrd"
4872 images; of course this also means that different kernel images can
4873 be run with the same "initrd". This makes testing easier (you don't
4874 have to build a new "zImage.initrd" Linux image when you just
4875 change a file in your "initrd"). Also, a field-upgrade of the
4876 software is easier now.
4882 Porting Linux to U-Boot based systems:
4883 ---------------------------------------
4885 U-Boot cannot save you from doing all the necessary modifications to
4886 configure the Linux device drivers for use with your target hardware
4887 (no, we don't intend to provide a full virtual machine interface to
4890 But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
4892 Just make sure your machine specific header file (for instance
4893 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
4894 Information structure as we define in include/asm-<arch>/u-boot.h,
4895 and make sure that your definition of IMAP_ADDR uses the same value
4896 as your U-Boot configuration in CONFIG_SYS_IMMR.
4899 Configuring the Linux kernel:
4900 -----------------------------
4902 No specific requirements for U-Boot. Make sure you have some root
4903 device (initial ramdisk, NFS) for your target system.
4906 Building a Linux Image:
4907 -----------------------
4909 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
4910 not used. If you use recent kernel source, a new build target
4911 "uImage" will exist which automatically builds an image usable by
4912 U-Boot. Most older kernels also have support for a "pImage" target,
4913 which was introduced for our predecessor project PPCBoot and uses a
4914 100% compatible format.
4923 The "uImage" build target uses a special tool (in 'tools/mkimage') to
4924 encapsulate a compressed Linux kernel image with header information,
4925 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
4927 * build a standard "vmlinux" kernel image (in ELF binary format):
4929 * convert the kernel into a raw binary image:
4931 ${CROSS_COMPILE}-objcopy -O binary \
4932 -R .note -R .comment \
4933 -S vmlinux linux.bin
4935 * compress the binary image:
4939 * package compressed binary image for U-Boot:
4941 mkimage -A ppc -O linux -T kernel -C gzip \
4942 -a 0 -e 0 -n "Linux Kernel Image" \
4943 -d linux.bin.gz uImage
4946 The "mkimage" tool can also be used to create ramdisk images for use
4947 with U-Boot, either separated from the Linux kernel image, or
4948 combined into one file. "mkimage" encapsulates the images with a 64
4949 byte header containing information about target architecture,
4950 operating system, image type, compression method, entry points, time
4951 stamp, CRC32 checksums, etc.
4953 "mkimage" can be called in two ways: to verify existing images and
4954 print the header information, or to build new images.
4956 In the first form (with "-l" option) mkimage lists the information
4957 contained in the header of an existing U-Boot image; this includes
4958 checksum verification:
4960 tools/mkimage -l image
4961 -l ==> list image header information
4963 The second form (with "-d" option) is used to build a U-Boot image
4964 from a "data file" which is used as image payload:
4966 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
4967 -n name -d data_file image
4968 -A ==> set architecture to 'arch'
4969 -O ==> set operating system to 'os'
4970 -T ==> set image type to 'type'
4971 -C ==> set compression type 'comp'
4972 -a ==> set load address to 'addr' (hex)
4973 -e ==> set entry point to 'ep' (hex)
4974 -n ==> set image name to 'name'
4975 -d ==> use image data from 'datafile'
4977 Right now, all Linux kernels for PowerPC systems use the same load
4978 address (0x00000000), but the entry point address depends on the
4981 - 2.2.x kernels have the entry point at 0x0000000C,
4982 - 2.3.x and later kernels have the entry point at 0x00000000.
4984 So a typical call to build a U-Boot image would read:
4986 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
4987 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
4988 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
4989 > examples/uImage.TQM850L
4990 Image Name: 2.4.4 kernel for TQM850L
4991 Created: Wed Jul 19 02:34:59 2000
4992 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4993 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
4994 Load Address: 0x00000000
4995 Entry Point: 0x00000000
4997 To verify the contents of the image (or check for corruption):
4999 -> tools/mkimage -l examples/uImage.TQM850L
5000 Image Name: 2.4.4 kernel for TQM850L
5001 Created: Wed Jul 19 02:34:59 2000
5002 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5003 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
5004 Load Address: 0x00000000
5005 Entry Point: 0x00000000
5007 NOTE: for embedded systems where boot time is critical you can trade
5008 speed for memory and install an UNCOMPRESSED image instead: this
5009 needs more space in Flash, but boots much faster since it does not
5010 need to be uncompressed:
5012 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
5013 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
5014 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
5015 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
5016 > examples/uImage.TQM850L-uncompressed
5017 Image Name: 2.4.4 kernel for TQM850L
5018 Created: Wed Jul 19 02:34:59 2000
5019 Image Type: PowerPC Linux Kernel Image (uncompressed)
5020 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
5021 Load Address: 0x00000000
5022 Entry Point: 0x00000000
5025 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
5026 when your kernel is intended to use an initial ramdisk:
5028 -> tools/mkimage -n 'Simple Ramdisk Image' \
5029 > -A ppc -O linux -T ramdisk -C gzip \
5030 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
5031 Image Name: Simple Ramdisk Image
5032 Created: Wed Jan 12 14:01:50 2000
5033 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5034 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
5035 Load Address: 0x00000000
5036 Entry Point: 0x00000000
5039 Installing a Linux Image:
5040 -------------------------
5042 To downloading a U-Boot image over the serial (console) interface,
5043 you must convert the image to S-Record format:
5045 objcopy -I binary -O srec examples/image examples/image.srec
5047 The 'objcopy' does not understand the information in the U-Boot
5048 image header, so the resulting S-Record file will be relative to
5049 address 0x00000000. To load it to a given address, you need to
5050 specify the target address as 'offset' parameter with the 'loads'
5053 Example: install the image to address 0x40100000 (which on the
5054 TQM8xxL is in the first Flash bank):
5056 => erase 40100000 401FFFFF
5062 ## Ready for S-Record download ...
5063 ~>examples/image.srec
5064 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
5066 15989 15990 15991 15992
5067 [file transfer complete]
5069 ## Start Addr = 0x00000000
5072 You can check the success of the download using the 'iminfo' command;
5073 this includes a checksum verification so you can be sure no data
5074 corruption happened:
5078 ## Checking Image at 40100000 ...
5079 Image Name: 2.2.13 for initrd on TQM850L
5080 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5081 Data Size: 335725 Bytes = 327 kB = 0 MB
5082 Load Address: 00000000
5083 Entry Point: 0000000c
5084 Verifying Checksum ... OK
5090 The "bootm" command is used to boot an application that is stored in
5091 memory (RAM or Flash). In case of a Linux kernel image, the contents
5092 of the "bootargs" environment variable is passed to the kernel as
5093 parameters. You can check and modify this variable using the
5094 "printenv" and "setenv" commands:
5097 => printenv bootargs
5098 bootargs=root=/dev/ram
5100 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5102 => printenv bootargs
5103 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5106 ## Booting Linux kernel at 40020000 ...
5107 Image Name: 2.2.13 for NFS on TQM850L
5108 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5109 Data Size: 381681 Bytes = 372 kB = 0 MB
5110 Load Address: 00000000
5111 Entry Point: 0000000c
5112 Verifying Checksum ... OK
5113 Uncompressing Kernel Image ... OK
5114 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
5115 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5116 time_init: decrementer frequency = 187500000/60
5117 Calibrating delay loop... 49.77 BogoMIPS
5118 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
5121 If you want to boot a Linux kernel with initial RAM disk, you pass
5122 the memory addresses of both the kernel and the initrd image (PPBCOOT
5123 format!) to the "bootm" command:
5125 => imi 40100000 40200000
5127 ## Checking Image at 40100000 ...
5128 Image Name: 2.2.13 for initrd on TQM850L
5129 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5130 Data Size: 335725 Bytes = 327 kB = 0 MB
5131 Load Address: 00000000
5132 Entry Point: 0000000c
5133 Verifying Checksum ... OK
5135 ## Checking Image at 40200000 ...
5136 Image Name: Simple Ramdisk Image
5137 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5138 Data Size: 566530 Bytes = 553 kB = 0 MB
5139 Load Address: 00000000
5140 Entry Point: 00000000
5141 Verifying Checksum ... OK
5143 => bootm 40100000 40200000
5144 ## Booting Linux kernel at 40100000 ...
5145 Image Name: 2.2.13 for initrd on TQM850L
5146 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5147 Data Size: 335725 Bytes = 327 kB = 0 MB
5148 Load Address: 00000000
5149 Entry Point: 0000000c
5150 Verifying Checksum ... OK
5151 Uncompressing Kernel Image ... OK
5152 ## Loading RAMDisk Image at 40200000 ...
5153 Image Name: Simple Ramdisk Image
5154 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5155 Data Size: 566530 Bytes = 553 kB = 0 MB
5156 Load Address: 00000000
5157 Entry Point: 00000000
5158 Verifying Checksum ... OK
5159 Loading Ramdisk ... OK
5160 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
5161 Boot arguments: root=/dev/ram
5162 time_init: decrementer frequency = 187500000/60
5163 Calibrating delay loop... 49.77 BogoMIPS
5165 RAMDISK: Compressed image found at block 0
5166 VFS: Mounted root (ext2 filesystem).
5170 Boot Linux and pass a flat device tree:
5173 First, U-Boot must be compiled with the appropriate defines. See the section
5174 titled "Linux Kernel Interface" above for a more in depth explanation. The
5175 following is an example of how to start a kernel and pass an updated
5181 oft=oftrees/mpc8540ads.dtb
5182 => tftp $oftaddr $oft
5183 Speed: 1000, full duplex
5185 TFTP from server 192.168.1.1; our IP address is 192.168.1.101
5186 Filename 'oftrees/mpc8540ads.dtb'.
5187 Load address: 0x300000
5190 Bytes transferred = 4106 (100a hex)
5191 => tftp $loadaddr $bootfile
5192 Speed: 1000, full duplex
5194 TFTP from server 192.168.1.1; our IP address is 192.168.1.2
5196 Load address: 0x200000
5197 Loading:############
5199 Bytes transferred = 1029407 (fb51f hex)
5204 => bootm $loadaddr - $oftaddr
5205 ## Booting image at 00200000 ...
5206 Image Name: Linux-2.6.17-dirty
5207 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5208 Data Size: 1029343 Bytes = 1005.2 kB
5209 Load Address: 00000000
5210 Entry Point: 00000000
5211 Verifying Checksum ... OK
5212 Uncompressing Kernel Image ... OK
5213 Booting using flat device tree at 0x300000
5214 Using MPC85xx ADS machine description
5215 Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
5219 More About U-Boot Image Types:
5220 ------------------------------
5222 U-Boot supports the following image types:
5224 "Standalone Programs" are directly runnable in the environment
5225 provided by U-Boot; it is expected that (if they behave
5226 well) you can continue to work in U-Boot after return from
5227 the Standalone Program.
5228 "OS Kernel Images" are usually images of some Embedded OS which
5229 will take over control completely. Usually these programs
5230 will install their own set of exception handlers, device
5231 drivers, set up the MMU, etc. - this means, that you cannot
5232 expect to re-enter U-Boot except by resetting the CPU.
5233 "RAMDisk Images" are more or less just data blocks, and their
5234 parameters (address, size) are passed to an OS kernel that is
5236 "Multi-File Images" contain several images, typically an OS
5237 (Linux) kernel image and one or more data images like
5238 RAMDisks. This construct is useful for instance when you want
5239 to boot over the network using BOOTP etc., where the boot
5240 server provides just a single image file, but you want to get
5241 for instance an OS kernel and a RAMDisk image.
5243 "Multi-File Images" start with a list of image sizes, each
5244 image size (in bytes) specified by an "uint32_t" in network
5245 byte order. This list is terminated by an "(uint32_t)0".
5246 Immediately after the terminating 0 follow the images, one by
5247 one, all aligned on "uint32_t" boundaries (size rounded up to
5248 a multiple of 4 bytes).
5250 "Firmware Images" are binary images containing firmware (like
5251 U-Boot or FPGA images) which usually will be programmed to
5254 "Script files" are command sequences that will be executed by
5255 U-Boot's command interpreter; this feature is especially
5256 useful when you configure U-Boot to use a real shell (hush)
5257 as command interpreter.
5259 Booting the Linux zImage:
5260 -------------------------
5262 On some platforms, it's possible to boot Linux zImage. This is done
5263 using the "bootz" command. The syntax of "bootz" command is the same
5264 as the syntax of "bootm" command.
5266 Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply
5267 kernel with raw initrd images. The syntax is slightly different, the
5268 address of the initrd must be augmented by it's size, in the following
5269 format: "<initrd addres>:<initrd size>".
5275 One of the features of U-Boot is that you can dynamically load and
5276 run "standalone" applications, which can use some resources of
5277 U-Boot like console I/O functions or interrupt services.
5279 Two simple examples are included with the sources:
5284 'examples/hello_world.c' contains a small "Hello World" Demo
5285 application; it is automatically compiled when you build U-Boot.
5286 It's configured to run at address 0x00040004, so you can play with it
5290 ## Ready for S-Record download ...
5291 ~>examples/hello_world.srec
5292 1 2 3 4 5 6 7 8 9 10 11 ...
5293 [file transfer complete]
5295 ## Start Addr = 0x00040004
5297 => go 40004 Hello World! This is a test.
5298 ## Starting application at 0x00040004 ...
5309 Hit any key to exit ...
5311 ## Application terminated, rc = 0x0
5313 Another example, which demonstrates how to register a CPM interrupt
5314 handler with the U-Boot code, can be found in 'examples/timer.c'.
5315 Here, a CPM timer is set up to generate an interrupt every second.
5316 The interrupt service routine is trivial, just printing a '.'
5317 character, but this is just a demo program. The application can be
5318 controlled by the following keys:
5320 ? - print current values og the CPM Timer registers
5321 b - enable interrupts and start timer
5322 e - stop timer and disable interrupts
5323 q - quit application
5326 ## Ready for S-Record download ...
5327 ~>examples/timer.srec
5328 1 2 3 4 5 6 7 8 9 10 11 ...
5329 [file transfer complete]
5331 ## Start Addr = 0x00040004
5334 ## Starting application at 0x00040004 ...
5337 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
5340 [q, b, e, ?] Set interval 1000000 us
5343 [q, b, e, ?] ........
5344 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
5347 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
5350 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
5353 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
5355 [q, b, e, ?] ...Stopping timer
5357 [q, b, e, ?] ## Application terminated, rc = 0x0
5363 Over time, many people have reported problems when trying to use the
5364 "minicom" terminal emulation program for serial download. I (wd)
5365 consider minicom to be broken, and recommend not to use it. Under
5366 Unix, I recommend to use C-Kermit for general purpose use (and
5367 especially for kermit binary protocol download ("loadb" command), and
5368 use "cu" for S-Record download ("loads" command). See
5369 http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3.
5370 for help with kermit.
5373 Nevertheless, if you absolutely want to use it try adding this
5374 configuration to your "File transfer protocols" section:
5376 Name Program Name U/D FullScr IO-Red. Multi
5377 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
5378 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
5384 Starting at version 0.9.2, U-Boot supports NetBSD both as host
5385 (build U-Boot) and target system (boots NetBSD/mpc8xx).
5387 Building requires a cross environment; it is known to work on
5388 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
5389 need gmake since the Makefiles are not compatible with BSD make).
5390 Note that the cross-powerpc package does not install include files;
5391 attempting to build U-Boot will fail because <machine/ansi.h> is
5392 missing. This file has to be installed and patched manually:
5394 # cd /usr/pkg/cross/powerpc-netbsd/include
5396 # ln -s powerpc machine
5397 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
5398 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
5400 Native builds *don't* work due to incompatibilities between native
5401 and U-Boot include files.
5403 Booting assumes that (the first part of) the image booted is a
5404 stage-2 loader which in turn loads and then invokes the kernel
5405 proper. Loader sources will eventually appear in the NetBSD source
5406 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
5407 meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
5410 Implementation Internals:
5411 =========================
5413 The following is not intended to be a complete description of every
5414 implementation detail. However, it should help to understand the
5415 inner workings of U-Boot and make it easier to port it to custom
5419 Initial Stack, Global Data:
5420 ---------------------------
5422 The implementation of U-Boot is complicated by the fact that U-Boot
5423 starts running out of ROM (flash memory), usually without access to
5424 system RAM (because the memory controller is not initialized yet).
5425 This means that we don't have writable Data or BSS segments, and BSS
5426 is not initialized as zero. To be able to get a C environment working
5427 at all, we have to allocate at least a minimal stack. Implementation
5428 options for this are defined and restricted by the CPU used: Some CPU
5429 models provide on-chip memory (like the IMMR area on MPC8xx and
5430 MPC826x processors), on others (parts of) the data cache can be
5431 locked as (mis-) used as memory, etc.
5433 Chris Hallinan posted a good summary of these issues to the
5434 U-Boot mailing list:
5436 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
5437 From: "Chris Hallinan" <clh@net1plus.com>
5438 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
5441 Correct me if I'm wrong, folks, but the way I understand it
5442 is this: Using DCACHE as initial RAM for Stack, etc, does not
5443 require any physical RAM backing up the cache. The cleverness
5444 is that the cache is being used as a temporary supply of
5445 necessary storage before the SDRAM controller is setup. It's
5446 beyond the scope of this list to explain the details, but you
5447 can see how this works by studying the cache architecture and
5448 operation in the architecture and processor-specific manuals.
5450 OCM is On Chip Memory, which I believe the 405GP has 4K. It
5451 is another option for the system designer to use as an
5452 initial stack/RAM area prior to SDRAM being available. Either
5453 option should work for you. Using CS 4 should be fine if your
5454 board designers haven't used it for something that would
5455 cause you grief during the initial boot! It is frequently not
5458 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
5459 with your processor/board/system design. The default value
5460 you will find in any recent u-boot distribution in
5461 walnut.h should work for you. I'd set it to a value larger
5462 than your SDRAM module. If you have a 64MB SDRAM module, set
5463 it above 400_0000. Just make sure your board has no resources
5464 that are supposed to respond to that address! That code in
5465 start.S has been around a while and should work as is when
5466 you get the config right.
5471 It is essential to remember this, since it has some impact on the C
5472 code for the initialization procedures:
5474 * Initialized global data (data segment) is read-only. Do not attempt
5477 * Do not use any uninitialized global data (or implicitely initialized
5478 as zero data - BSS segment) at all - this is undefined, initiali-
5479 zation is performed later (when relocating to RAM).
5481 * Stack space is very limited. Avoid big data buffers or things like
5484 Having only the stack as writable memory limits means we cannot use
5485 normal global data to share information beween the code. But it
5486 turned out that the implementation of U-Boot can be greatly
5487 simplified by making a global data structure (gd_t) available to all
5488 functions. We could pass a pointer to this data as argument to _all_
5489 functions, but this would bloat the code. Instead we use a feature of
5490 the GCC compiler (Global Register Variables) to share the data: we
5491 place a pointer (gd) to the global data into a register which we
5492 reserve for this purpose.
5494 When choosing a register for such a purpose we are restricted by the
5495 relevant (E)ABI specifications for the current architecture, and by
5496 GCC's implementation.
5498 For PowerPC, the following registers have specific use:
5500 R2: reserved for system use
5501 R3-R4: parameter passing and return values
5502 R5-R10: parameter passing
5503 R13: small data area pointer
5507 (U-Boot also uses R12 as internal GOT pointer. r12
5508 is a volatile register so r12 needs to be reset when
5509 going back and forth between asm and C)
5511 ==> U-Boot will use R2 to hold a pointer to the global data
5513 Note: on PPC, we could use a static initializer (since the
5514 address of the global data structure is known at compile time),
5515 but it turned out that reserving a register results in somewhat
5516 smaller code - although the code savings are not that big (on
5517 average for all boards 752 bytes for the whole U-Boot image,
5518 624 text + 127 data).
5520 On Blackfin, the normal C ABI (except for P3) is followed as documented here:
5521 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface
5523 ==> U-Boot will use P3 to hold a pointer to the global data
5525 On ARM, the following registers are used:
5527 R0: function argument word/integer result
5528 R1-R3: function argument word
5530 R10: stack limit (used only if stack checking if enabled)
5531 R11: argument (frame) pointer
5532 R12: temporary workspace
5535 R15: program counter
5537 ==> U-Boot will use R8 to hold a pointer to the global data
5539 On Nios II, the ABI is documented here:
5540 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
5542 ==> U-Boot will use gp to hold a pointer to the global data
5544 Note: on Nios II, we give "-G0" option to gcc and don't use gp
5545 to access small data sections, so gp is free.
5547 On NDS32, the following registers are used:
5549 R0-R1: argument/return
5551 R15: temporary register for assembler
5552 R16: trampoline register
5553 R28: frame pointer (FP)
5554 R29: global pointer (GP)
5555 R30: link register (LP)
5556 R31: stack pointer (SP)
5557 PC: program counter (PC)
5559 ==> U-Boot will use R10 to hold a pointer to the global data
5561 NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
5562 or current versions of GCC may "optimize" the code too much.
5567 U-Boot runs in system state and uses physical addresses, i.e. the
5568 MMU is not used either for address mapping nor for memory protection.
5570 The available memory is mapped to fixed addresses using the memory
5571 controller. In this process, a contiguous block is formed for each
5572 memory type (Flash, SDRAM, SRAM), even when it consists of several
5573 physical memory banks.
5575 U-Boot is installed in the first 128 kB of the first Flash bank (on
5576 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
5577 booting and sizing and initializing DRAM, the code relocates itself
5578 to the upper end of DRAM. Immediately below the U-Boot code some
5579 memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
5580 configuration setting]. Below that, a structure with global Board
5581 Info data is placed, followed by the stack (growing downward).
5583 Additionally, some exception handler code is copied to the low 8 kB
5584 of DRAM (0x00000000 ... 0x00001FFF).
5586 So a typical memory configuration with 16 MB of DRAM could look like
5589 0x0000 0000 Exception Vector code
5592 0x0000 2000 Free for Application Use
5598 0x00FB FF20 Monitor Stack (Growing downward)
5599 0x00FB FFAC Board Info Data and permanent copy of global data
5600 0x00FC 0000 Malloc Arena
5603 0x00FE 0000 RAM Copy of Monitor Code
5604 ... eventually: LCD or video framebuffer
5605 ... eventually: pRAM (Protected RAM - unchanged by reset)
5606 0x00FF FFFF [End of RAM]
5609 System Initialization:
5610 ----------------------
5612 In the reset configuration, U-Boot starts at the reset entry point
5613 (on most PowerPC systems at address 0x00000100). Because of the reset
5614 configuration for CS0# this is a mirror of the onboard Flash memory.
5615 To be able to re-map memory U-Boot then jumps to its link address.
5616 To be able to implement the initialization code in C, a (small!)
5617 initial stack is set up in the internal Dual Ported RAM (in case CPUs
5618 which provide such a feature like MPC8xx or MPC8260), or in a locked
5619 part of the data cache. After that, U-Boot initializes the CPU core,
5620 the caches and the SIU.
5622 Next, all (potentially) available memory banks are mapped using a
5623 preliminary mapping. For example, we put them on 512 MB boundaries
5624 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
5625 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
5626 programmed for SDRAM access. Using the temporary configuration, a
5627 simple memory test is run that determines the size of the SDRAM
5630 When there is more than one SDRAM bank, and the banks are of
5631 different size, the largest is mapped first. For equal size, the first
5632 bank (CS2#) is mapped first. The first mapping is always for address
5633 0x00000000, with any additional banks following immediately to create
5634 contiguous memory starting from 0.
5636 Then, the monitor installs itself at the upper end of the SDRAM area
5637 and allocates memory for use by malloc() and for the global Board
5638 Info data; also, the exception vector code is copied to the low RAM
5639 pages, and the final stack is set up.
5641 Only after this relocation will you have a "normal" C environment;
5642 until that you are restricted in several ways, mostly because you are
5643 running from ROM, and because the code will have to be relocated to a
5647 U-Boot Porting Guide:
5648 ----------------------
5650 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
5654 int main(int argc, char *argv[])
5656 sighandler_t no_more_time;
5658 signal(SIGALRM, no_more_time);
5659 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
5661 if (available_money > available_manpower) {
5662 Pay consultant to port U-Boot;
5666 Download latest U-Boot source;
5668 Subscribe to u-boot mailing list;
5671 email("Hi, I am new to U-Boot, how do I get started?");
5674 Read the README file in the top level directory;
5675 Read http://www.denx.de/twiki/bin/view/DULG/Manual;
5676 Read applicable doc/*.README;
5677 Read the source, Luke;
5678 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
5681 if (available_money > toLocalCurrency ($2500))
5684 Add a lot of aggravation and time;
5686 if (a similar board exists) { /* hopefully... */
5687 cp -a board/<similar> board/<myboard>
5688 cp include/configs/<similar>.h include/configs/<myboard>.h
5690 Create your own board support subdirectory;
5691 Create your own board include/configs/<myboard>.h file;
5693 Edit new board/<myboard> files
5694 Edit new include/configs/<myboard>.h
5699 Add / modify source code;
5703 email("Hi, I am having problems...");
5705 Send patch file to the U-Boot email list;
5706 if (reasonable critiques)
5707 Incorporate improvements from email list code review;
5709 Defend code as written;
5715 void no_more_time (int sig)
5724 All contributions to U-Boot should conform to the Linux kernel
5725 coding style; see the file "Documentation/CodingStyle" and the script
5726 "scripts/Lindent" in your Linux kernel source directory.
5728 Source files originating from a different project (for example the
5729 MTD subsystem) are generally exempt from these guidelines and are not
5730 reformated to ease subsequent migration to newer versions of those
5733 Please note that U-Boot is implemented in C (and to some small parts in
5734 Assembler); no C++ is used, so please do not use C++ style comments (//)
5737 Please also stick to the following formatting rules:
5738 - remove any trailing white space
5739 - use TAB characters for indentation and vertical alignment, not spaces
5740 - make sure NOT to use DOS '\r\n' line feeds
5741 - do not add more than 2 consecutive empty lines to source files
5742 - do not add trailing empty lines to source files
5744 Submissions which do not conform to the standards may be returned
5745 with a request to reformat the changes.
5751 Since the number of patches for U-Boot is growing, we need to
5752 establish some rules. Submissions which do not conform to these rules
5753 may be rejected, even when they contain important and valuable stuff.
5755 Please see http://www.denx.de/wiki/U-Boot/Patches for details.
5757 Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
5758 see http://lists.denx.de/mailman/listinfo/u-boot
5760 When you send a patch, please include the following information with
5763 * For bug fixes: a description of the bug and how your patch fixes
5764 this bug. Please try to include a way of demonstrating that the
5765 patch actually fixes something.
5767 * For new features: a description of the feature and your
5770 * A CHANGELOG entry as plaintext (separate from the patch)
5772 * For major contributions, your entry to the CREDITS file
5774 * When you add support for a new board, don't forget to add this
5775 board to the MAINTAINERS file, too.
5777 * If your patch adds new configuration options, don't forget to
5778 document these in the README file.
5780 * The patch itself. If you are using git (which is *strongly*
5781 recommended) you can easily generate the patch using the
5782 "git format-patch". If you then use "git send-email" to send it to
5783 the U-Boot mailing list, you will avoid most of the common problems
5784 with some other mail clients.
5786 If you cannot use git, use "diff -purN OLD NEW". If your version of
5787 diff does not support these options, then get the latest version of
5790 The current directory when running this command shall be the parent
5791 directory of the U-Boot source tree (i. e. please make sure that
5792 your patch includes sufficient directory information for the
5795 We prefer patches as plain text. MIME attachments are discouraged,
5796 and compressed attachments must not be used.
5798 * If one logical set of modifications affects or creates several
5799 files, all these changes shall be submitted in a SINGLE patch file.
5801 * Changesets that contain different, unrelated modifications shall be
5802 submitted as SEPARATE patches, one patch per changeset.
5807 * Before sending the patch, run the MAKEALL script on your patched
5808 source tree and make sure that no errors or warnings are reported
5809 for any of the boards.
5811 * Keep your modifications to the necessary minimum: A patch
5812 containing several unrelated changes or arbitrary reformats will be
5813 returned with a request to re-formatting / split it.
5815 * If you modify existing code, make sure that your new code does not
5816 add to the memory footprint of the code ;-) Small is beautiful!
5817 When adding new features, these should compile conditionally only
5818 (using #ifdef), and the resulting code with the new feature
5819 disabled must not need more memory than the old code without your
5822 * Remember that there is a size limit of 100 kB per message on the
5823 u-boot mailing list. Bigger patches will be moderated. If they are
5824 reasonable and not too big, they will be acknowledged. But patches
5825 bigger than the size limit should be avoided.
projects / kernel / u-boot.git / blob