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 - Generic CPU options:
417 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN
419 Defines the endianess of the CPU. Implementation of those
420 values is arch specific.
422 - Intel Monahans options:
423 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO
425 Defines the Monahans run mode to oscillator
426 ratio. Valid values are 8, 16, 24, 31. The core
427 frequency is this value multiplied by 13 MHz.
429 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO
431 Defines the Monahans turbo mode to oscillator
432 ratio. Valid values are 1 (default if undefined) and
433 2. The core frequency as calculated above is multiplied
437 CONFIG_SYS_INIT_SP_OFFSET
439 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack
440 pointer. This is needed for the temporary stack before
443 CONFIG_SYS_MIPS_CACHE_MODE
445 Cache operation mode for the MIPS CPU.
446 See also arch/mips/include/asm/mipsregs.h.
448 CONF_CM_CACHABLE_NO_WA
451 CONF_CM_CACHABLE_NONCOHERENT
455 CONF_CM_CACHABLE_ACCELERATED
457 CONFIG_SYS_XWAY_EBU_BOOTCFG
459 Special option for Lantiq XWAY SoCs for booting from NOR flash.
460 See also arch/mips/cpu/mips32/start.S.
462 CONFIG_XWAY_SWAP_BYTES
464 Enable compilation of tools/xway-swap-bytes needed for Lantiq
465 XWAY SoCs for booting from NOR flash. The U-Boot image needs to
466 be swapped if a flash programmer is used.
469 CONFIG_SYS_EXCEPTION_VECTORS_HIGH
471 Select high exception vectors of the ARM core, e.g., do not
472 clear the V bit of the c1 register of CP15.
474 CONFIG_SYS_THUMB_BUILD
476 Use this flag to build U-Boot using the Thumb instruction
477 set for ARM architectures. Thumb instruction set provides
478 better code density. For ARM architectures that support
479 Thumb2 this flag will result in Thumb2 code generated by
482 CONFIG_ARM_ERRATA_716044
483 CONFIG_ARM_ERRATA_742230
484 CONFIG_ARM_ERRATA_743622
485 CONFIG_ARM_ERRATA_751472
487 If set, the workarounds for these ARM errata are applied early
488 during U-Boot startup. Note that these options force the
489 workarounds to be applied; no CPU-type/version detection
490 exists, unlike the similar options in the Linux kernel. Do not
491 set these options unless they apply!
496 The frequency of the timer returned by get_timer().
497 get_timer() must operate in milliseconds and this CONFIG
498 option must be set to 1000.
500 - Linux Kernel Interface:
503 U-Boot stores all clock information in Hz
504 internally. For binary compatibility with older Linux
505 kernels (which expect the clocks passed in the
506 bd_info data to be in MHz) the environment variable
507 "clocks_in_mhz" can be defined so that U-Boot
508 converts clock data to MHZ before passing it to the
510 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
511 "clocks_in_mhz=1" is automatically included in the
514 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
516 When transferring memsize parameter to linux, some versions
517 expect it to be in bytes, others in MB.
518 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
522 New kernel versions are expecting firmware settings to be
523 passed using flattened device trees (based on open firmware
527 * New libfdt-based support
528 * Adds the "fdt" command
529 * The bootm command automatically updates the fdt
531 OF_CPU - The proper name of the cpus node (only required for
532 MPC512X and MPC5xxx based boards).
533 OF_SOC - The proper name of the soc node (only required for
534 MPC512X and MPC5xxx based boards).
535 OF_TBCLK - The timebase frequency.
536 OF_STDOUT_PATH - The path to the console device
538 boards with QUICC Engines require OF_QE to set UCC MAC
541 CONFIG_OF_BOARD_SETUP
543 Board code has addition modification that it wants to make
544 to the flat device tree before handing it off to the kernel
548 This define fills in the correct boot CPU in the boot
549 param header, the default value is zero if undefined.
553 U-Boot can detect if an IDE device is present or not.
554 If not, and this new config option is activated, U-Boot
555 removes the ATA node from the DTS before booting Linux,
556 so the Linux IDE driver does not probe the device and
557 crash. This is needed for buggy hardware (uc101) where
558 no pull down resistor is connected to the signal IDE5V_DD7.
560 CONFIG_MACH_TYPE [relevant for ARM only][mandatory]
562 This setting is mandatory for all boards that have only one
563 machine type and must be used to specify the machine type
564 number as it appears in the ARM machine registry
565 (see http://www.arm.linux.org.uk/developer/machines/).
566 Only boards that have multiple machine types supported
567 in a single configuration file and the machine type is
568 runtime discoverable, do not have to use this setting.
570 - vxWorks boot parameters:
572 bootvx constructs a valid bootline using the following
573 environments variables: bootfile, ipaddr, serverip, hostname.
574 It loads the vxWorks image pointed bootfile.
576 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name
577 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address
578 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server
579 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters
581 CONFIG_SYS_VXWORKS_ADD_PARAMS
583 Add it at the end of the bootline. E.g "u=username pw=secret"
585 Note: If a "bootargs" environment is defined, it will overwride
586 the defaults discussed just above.
588 - Cache Configuration:
589 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot
590 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot
591 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot
593 - Cache Configuration for ARM:
594 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache
596 CONFIG_SYS_PL310_BASE - Physical base address of PL310
597 controller register space
602 Define this if you want support for Amba PrimeCell PL010 UARTs.
606 Define this if you want support for Amba PrimeCell PL011 UARTs.
610 If you have Amba PrimeCell PL011 UARTs, set this variable to
611 the clock speed of the UARTs.
615 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
616 define this to a list of base addresses for each (supported)
617 port. See e.g. include/configs/versatile.h
619 CONFIG_PL011_SERIAL_RLCR
621 Some vendor versions of PL011 serial ports (e.g. ST-Ericsson U8500)
622 have separate receive and transmit line control registers. Set
623 this variable to initialize the extra register.
625 CONFIG_PL011_SERIAL_FLUSH_ON_INIT
627 On some platforms (e.g. U8500) U-Boot is loaded by a second stage
628 boot loader that has already initialized the UART. Define this
629 variable to flush the UART at init time.
633 Depending on board, define exactly one serial port
634 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
635 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
636 console by defining CONFIG_8xx_CONS_NONE
638 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
639 port routines must be defined elsewhere
640 (i.e. serial_init(), serial_getc(), ...)
643 Enables console device for a color framebuffer. Needs following
644 defines (cf. smiLynxEM, i8042)
645 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
647 VIDEO_HW_RECTFILL graphic chip supports
650 VIDEO_HW_BITBLT graphic chip supports
651 bit-blit (cf. smiLynxEM)
652 VIDEO_VISIBLE_COLS visible pixel columns
654 VIDEO_VISIBLE_ROWS visible pixel rows
655 VIDEO_PIXEL_SIZE bytes per pixel
656 VIDEO_DATA_FORMAT graphic data format
657 (0-5, cf. cfb_console.c)
658 VIDEO_FB_ADRS framebuffer address
659 VIDEO_KBD_INIT_FCT keyboard int fct
660 (i.e. i8042_kbd_init())
661 VIDEO_TSTC_FCT test char fct
663 VIDEO_GETC_FCT get char fct
665 CONFIG_CONSOLE_CURSOR cursor drawing on/off
666 (requires blink timer
668 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
669 CONFIG_CONSOLE_TIME display time/date info in
671 (requires CONFIG_CMD_DATE)
672 CONFIG_VIDEO_LOGO display Linux logo in
674 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
675 linux_logo.h for logo.
676 Requires CONFIG_VIDEO_LOGO
677 CONFIG_CONSOLE_EXTRA_INFO
678 additional board info beside
681 When CONFIG_CFB_CONSOLE_ANSI is defined, console will support
682 a limited number of ANSI escape sequences (cursor control,
683 erase functions and limited graphics rendition control).
685 When CONFIG_CFB_CONSOLE is defined, video console is
686 default i/o. Serial console can be forced with
687 environment 'console=serial'.
689 When CONFIG_SILENT_CONSOLE is defined, all console
690 messages (by U-Boot and Linux!) can be silenced with
691 the "silent" environment variable. See
692 doc/README.silent for more information.
695 CONFIG_BAUDRATE - in bps
696 Select one of the baudrates listed in
697 CONFIG_SYS_BAUDRATE_TABLE, see below.
698 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale
700 - Console Rx buffer length
701 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define
702 the maximum receive buffer length for the SMC.
703 This option is actual only for 82xx and 8xx possible.
704 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE
705 must be defined, to setup the maximum idle timeout for
708 - Pre-Console Buffer:
709 Prior to the console being initialised (i.e. serial UART
710 initialised etc) all console output is silently discarded.
711 Defining CONFIG_PRE_CONSOLE_BUFFER will cause U-Boot to
712 buffer any console messages prior to the console being
713 initialised to a buffer of size CONFIG_PRE_CON_BUF_SZ
714 bytes located at CONFIG_PRE_CON_BUF_ADDR. The buffer is
715 a circular buffer, so if more than CONFIG_PRE_CON_BUF_SZ
716 bytes are output before the console is initialised, the
717 earlier bytes are discarded.
719 'Sane' compilers will generate smaller code if
720 CONFIG_PRE_CON_BUF_SZ is a power of 2
722 - Safe printf() functions
723 Define CONFIG_SYS_VSNPRINTF to compile in safe versions of
724 the printf() functions. These are defined in
725 include/vsprintf.h and include snprintf(), vsnprintf() and
726 so on. Code size increase is approximately 300-500 bytes.
727 If this option is not given then these functions will
728 silently discard their buffer size argument - this means
729 you are not getting any overflow checking in this case.
731 - Boot Delay: CONFIG_BOOTDELAY - in seconds
732 Delay before automatically booting the default image;
733 set to -1 to disable autoboot.
734 set to -2 to autoboot with no delay and not check for abort
735 (even when CONFIG_ZERO_BOOTDELAY_CHECK is defined).
737 See doc/README.autoboot for these options that
738 work with CONFIG_BOOTDELAY. None are required.
739 CONFIG_BOOT_RETRY_TIME
740 CONFIG_BOOT_RETRY_MIN
741 CONFIG_AUTOBOOT_KEYED
742 CONFIG_AUTOBOOT_PROMPT
743 CONFIG_AUTOBOOT_DELAY_STR
744 CONFIG_AUTOBOOT_STOP_STR
745 CONFIG_AUTOBOOT_DELAY_STR2
746 CONFIG_AUTOBOOT_STOP_STR2
747 CONFIG_ZERO_BOOTDELAY_CHECK
748 CONFIG_RESET_TO_RETRY
752 Only needed when CONFIG_BOOTDELAY is enabled;
753 define a command string that is automatically executed
754 when no character is read on the console interface
755 within "Boot Delay" after reset.
758 This can be used to pass arguments to the bootm
759 command. The value of CONFIG_BOOTARGS goes into the
760 environment value "bootargs".
762 CONFIG_RAMBOOT and CONFIG_NFSBOOT
763 The value of these goes into the environment as
764 "ramboot" and "nfsboot" respectively, and can be used
765 as a convenience, when switching between booting from
771 When this option is #defined, the existence of the
772 environment variable "preboot" will be checked
773 immediately before starting the CONFIG_BOOTDELAY
774 countdown and/or running the auto-boot command resp.
775 entering interactive mode.
777 This feature is especially useful when "preboot" is
778 automatically generated or modified. For an example
779 see the LWMON board specific code: here "preboot" is
780 modified when the user holds down a certain
781 combination of keys on the (special) keyboard when
784 - Serial Download Echo Mode:
786 If defined to 1, all characters received during a
787 serial download (using the "loads" command) are
788 echoed back. This might be needed by some terminal
789 emulations (like "cu"), but may as well just take
790 time on others. This setting #define's the initial
791 value of the "loads_echo" environment variable.
793 - Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
795 Select one of the baudrates listed in
796 CONFIG_SYS_BAUDRATE_TABLE, see below.
799 Monitor commands can be included or excluded
800 from the build by using the #include files
801 <config_cmd_all.h> and #undef'ing unwanted
802 commands, or using <config_cmd_default.h>
803 and augmenting with additional #define's
806 The default command configuration includes all commands
807 except those marked below with a "*".
809 CONFIG_CMD_ASKENV * ask for env variable
810 CONFIG_CMD_BDI bdinfo
811 CONFIG_CMD_BEDBUG * Include BedBug Debugger
812 CONFIG_CMD_BMP * BMP support
813 CONFIG_CMD_BSP * Board specific commands
814 CONFIG_CMD_BOOTD bootd
815 CONFIG_CMD_CACHE * icache, dcache
816 CONFIG_CMD_CONSOLE coninfo
817 CONFIG_CMD_CRC32 * crc32
818 CONFIG_CMD_DATE * support for RTC, date/time...
819 CONFIG_CMD_DHCP * DHCP support
820 CONFIG_CMD_DIAG * Diagnostics
821 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands
822 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command
823 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd
824 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command
825 CONFIG_CMD_DTT * Digital Therm and Thermostat
826 CONFIG_CMD_ECHO echo arguments
827 CONFIG_CMD_EDITENV edit env variable
828 CONFIG_CMD_EEPROM * EEPROM read/write support
829 CONFIG_CMD_ELF * bootelf, bootvx
830 CONFIG_CMD_ENV_CALLBACK * display details about env callbacks
831 CONFIG_CMD_ENV_FLAGS * display details about env flags
832 CONFIG_CMD_EXPORTENV * export the environment
833 CONFIG_CMD_EXT2 * ext2 command support
834 CONFIG_CMD_EXT4 * ext4 command support
835 CONFIG_CMD_SAVEENV saveenv
836 CONFIG_CMD_FDC * Floppy Disk Support
837 CONFIG_CMD_FAT * FAT command support
838 CONFIG_CMD_FDOS * Dos diskette Support
839 CONFIG_CMD_FLASH flinfo, erase, protect
840 CONFIG_CMD_FPGA FPGA device initialization support
841 CONFIG_CMD_FUSE * Device fuse support
842 CONFIG_CMD_GETTIME * Get time since boot
843 CONFIG_CMD_GO * the 'go' command (exec code)
844 CONFIG_CMD_GREPENV * search environment
845 CONFIG_CMD_HASH * calculate hash / digest
846 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control
847 CONFIG_CMD_I2C * I2C serial bus support
848 CONFIG_CMD_IDE * IDE harddisk support
849 CONFIG_CMD_IMI iminfo
850 CONFIG_CMD_IMLS List all images found in NOR flash
851 CONFIG_CMD_IMLS_NAND * List all images found in NAND flash
852 CONFIG_CMD_IMMAP * IMMR dump support
853 CONFIG_CMD_IMPORTENV * import an environment
854 CONFIG_CMD_INI * import data from an ini file into the env
855 CONFIG_CMD_IRQ * irqinfo
856 CONFIG_CMD_ITEST Integer/string test of 2 values
857 CONFIG_CMD_JFFS2 * JFFS2 Support
858 CONFIG_CMD_KGDB * kgdb
859 CONFIG_CMD_LDRINFO * ldrinfo (display Blackfin loader)
860 CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration
862 CONFIG_CMD_LOADB loadb
863 CONFIG_CMD_LOADS loads
864 CONFIG_CMD_MD5SUM * print md5 message digest
865 (requires CONFIG_CMD_MEMORY and CONFIG_MD5)
866 CONFIG_CMD_MEMINFO * Display detailed memory information
867 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
869 CONFIG_CMD_MEMTEST * mtest
870 CONFIG_CMD_MISC Misc functions like sleep etc
871 CONFIG_CMD_MMC * MMC memory mapped support
872 CONFIG_CMD_MII * MII utility commands
873 CONFIG_CMD_MTDPARTS * MTD partition support
874 CONFIG_CMD_NAND * NAND support
875 CONFIG_CMD_NET bootp, tftpboot, rarpboot
876 CONFIG_CMD_NFS NFS support
877 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands
878 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command
879 CONFIG_CMD_PCI * pciinfo
880 CONFIG_CMD_PCMCIA * PCMCIA support
881 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network
883 CONFIG_CMD_PORTIO * Port I/O
884 CONFIG_CMD_READ * Read raw data from partition
885 CONFIG_CMD_REGINFO * Register dump
886 CONFIG_CMD_RUN run command in env variable
887 CONFIG_CMD_SANDBOX * sb command to access sandbox features
888 CONFIG_CMD_SAVES * save S record dump
889 CONFIG_CMD_SCSI * SCSI Support
890 CONFIG_CMD_SDRAM * print SDRAM configuration information
891 (requires CONFIG_CMD_I2C)
892 CONFIG_CMD_SETGETDCR Support for DCR Register access
894 CONFIG_CMD_SF * Read/write/erase SPI NOR flash
895 CONFIG_CMD_SHA1SUM * print sha1 memory digest
896 (requires CONFIG_CMD_MEMORY)
897 CONFIG_CMD_SOFTSWITCH * Soft switch setting command for BF60x
898 CONFIG_CMD_SOURCE "source" command Support
899 CONFIG_CMD_SPI * SPI serial bus support
900 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode
901 CONFIG_CMD_TFTPPUT * TFTP put command (upload)
902 CONFIG_CMD_TIME * run command and report execution time (ARM specific)
903 CONFIG_CMD_TIMER * access to the system tick timer
904 CONFIG_CMD_USB * USB support
905 CONFIG_CMD_CDP * Cisco Discover Protocol support
906 CONFIG_CMD_MFSL * Microblaze FSL support
907 CONFIG_CMD_XIMG Load part of Multi Image
910 EXAMPLE: If you want all functions except of network
911 support you can write:
913 #include "config_cmd_all.h"
914 #undef CONFIG_CMD_NET
917 fdt (flattened device tree) command: CONFIG_OF_LIBFDT
919 Note: Don't enable the "icache" and "dcache" commands
920 (configuration option CONFIG_CMD_CACHE) unless you know
921 what you (and your U-Boot users) are doing. Data
922 cache cannot be enabled on systems like the 8xx or
923 8260 (where accesses to the IMMR region must be
924 uncached), and it cannot be disabled on all other
925 systems where we (mis-) use the data cache to hold an
926 initial stack and some data.
929 XXX - this list needs to get updated!
931 - Regular expression support:
933 If this variable is defined, U-Boot is linked against
934 the SLRE (Super Light Regular Expression) library,
935 which adds regex support to some commands, as for
936 example "env grep" and "setexpr".
940 If this variable is defined, U-Boot will use a device tree
941 to configure its devices, instead of relying on statically
942 compiled #defines in the board file. This option is
943 experimental and only available on a few boards. The device
944 tree is available in the global data as gd->fdt_blob.
946 U-Boot needs to get its device tree from somewhere. This can
947 be done using one of the two options below:
950 If this variable is defined, U-Boot will embed a device tree
951 binary in its image. This device tree file should be in the
952 board directory and called <soc>-<board>.dts. The binary file
953 is then picked up in board_init_f() and made available through
954 the global data structure as gd->blob.
957 If this variable is defined, U-Boot will build a device tree
958 binary. It will be called u-boot.dtb. Architecture-specific
959 code will locate it at run-time. Generally this works by:
961 cat u-boot.bin u-boot.dtb >image.bin
963 and in fact, U-Boot does this for you, creating a file called
964 u-boot-dtb.bin which is useful in the common case. You can
965 still use the individual files if you need something more
970 If this variable is defined, it enables watchdog
971 support for the SoC. There must be support in the SoC
972 specific code for a watchdog. For the 8xx and 8260
973 CPUs, the SIU Watchdog feature is enabled in the SYPCR
974 register. When supported for a specific SoC is
975 available, then no further board specific code should
979 When using a watchdog circuitry external to the used
980 SoC, then define this variable and provide board
981 specific code for the "hw_watchdog_reset" function.
984 CONFIG_VERSION_VARIABLE
985 If this variable is defined, an environment variable
986 named "ver" is created by U-Boot showing the U-Boot
987 version as printed by the "version" command.
988 Any change to this variable will be reverted at the
993 When CONFIG_CMD_DATE is selected, the type of the RTC
994 has to be selected, too. Define exactly one of the
997 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
998 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
999 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC
1000 CONFIG_RTC_MC146818 - use MC146818 RTC
1001 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
1002 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
1003 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
1004 CONFIG_RTC_DS164x - use Dallas DS164x RTC
1005 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
1006 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
1007 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
1008 CONFIG_SYS_RV3029_TCR - enable trickle charger on
1011 Note that if the RTC uses I2C, then the I2C interface
1012 must also be configured. See I2C Support, below.
1015 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
1016 CONFIG_PCA953X_INFO - enable pca953x info command
1018 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
1019 chip-ngpio pairs that tell the PCA953X driver the number of
1020 pins supported by a particular chip.
1022 Note that if the GPIO device uses I2C, then the I2C interface
1023 must also be configured. See I2C Support, below.
1025 - Timestamp Support:
1027 When CONFIG_TIMESTAMP is selected, the timestamp
1028 (date and time) of an image is printed by image
1029 commands like bootm or iminfo. This option is
1030 automatically enabled when you select CONFIG_CMD_DATE .
1032 - Partition Labels (disklabels) Supported:
1033 Zero or more of the following:
1034 CONFIG_MAC_PARTITION Apple's MacOS partition table.
1035 CONFIG_DOS_PARTITION MS Dos partition table, traditional on the
1036 Intel architecture, USB sticks, etc.
1037 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc.
1038 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the
1039 bootloader. Note 2TB partition limit; see
1041 CONFIG_MTD_PARTITIONS Memory Technology Device partition table.
1043 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or
1044 CONFIG_CMD_SCSI) you must configure support for at
1045 least one non-MTD partition type as well.
1048 CONFIG_IDE_RESET_ROUTINE - this is defined in several
1049 board configurations files but used nowhere!
1051 CONFIG_IDE_RESET - is this is defined, IDE Reset will
1052 be performed by calling the function
1053 ide_set_reset(int reset)
1054 which has to be defined in a board specific file
1059 Set this to enable ATAPI support.
1064 Set this to enable support for disks larger than 137GB
1065 Also look at CONFIG_SYS_64BIT_LBA.
1066 Whithout these , LBA48 support uses 32bit variables and will 'only'
1067 support disks up to 2.1TB.
1069 CONFIG_SYS_64BIT_LBA:
1070 When enabled, makes the IDE subsystem use 64bit sector addresses.
1074 At the moment only there is only support for the
1075 SYM53C8XX SCSI controller; define
1076 CONFIG_SCSI_SYM53C8XX to enable it.
1078 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
1079 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
1080 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
1081 maximum numbers of LUNs, SCSI ID's and target
1083 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
1085 The environment variable 'scsidevs' is set to the number of
1086 SCSI devices found during the last scan.
1088 - NETWORK Support (PCI):
1090 Support for Intel 8254x/8257x gigabit chips.
1093 Utility code for direct access to the SPI bus on Intel 8257x.
1094 This does not do anything useful unless you set at least one
1095 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC.
1097 CONFIG_E1000_SPI_GENERIC
1098 Allow generic access to the SPI bus on the Intel 8257x, for
1099 example with the "sspi" command.
1102 Management command for E1000 devices. When used on devices
1103 with SPI support you can reprogram the EEPROM from U-Boot.
1105 CONFIG_E1000_FALLBACK_MAC
1106 default MAC for empty EEPROM after production.
1109 Support for Intel 82557/82559/82559ER chips.
1110 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
1111 write routine for first time initialisation.
1114 Support for Digital 2114x chips.
1115 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
1116 modem chip initialisation (KS8761/QS6611).
1119 Support for National dp83815 chips.
1122 Support for National dp8382[01] gigabit chips.
1124 - NETWORK Support (other):
1126 CONFIG_DRIVER_AT91EMAC
1127 Support for AT91RM9200 EMAC.
1130 Define this to use reduced MII inteface
1132 CONFIG_DRIVER_AT91EMAC_QUIET
1133 If this defined, the driver is quiet.
1134 The driver doen't show link status messages.
1136 CONFIG_CALXEDA_XGMAC
1137 Support for the Calxeda XGMAC device
1140 Support for SMSC's LAN91C96 chips.
1142 CONFIG_LAN91C96_BASE
1143 Define this to hold the physical address
1144 of the LAN91C96's I/O space
1146 CONFIG_LAN91C96_USE_32_BIT
1147 Define this to enable 32 bit addressing
1150 Support for SMSC's LAN91C111 chip
1152 CONFIG_SMC91111_BASE
1153 Define this to hold the physical address
1154 of the device (I/O space)
1156 CONFIG_SMC_USE_32_BIT
1157 Define this if data bus is 32 bits
1159 CONFIG_SMC_USE_IOFUNCS
1160 Define this to use i/o functions instead of macros
1161 (some hardware wont work with macros)
1163 CONFIG_DRIVER_TI_EMAC
1164 Support for davinci emac
1166 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT
1167 Define this if you have more then 3 PHYs.
1170 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
1172 CONFIG_FTGMAC100_EGIGA
1173 Define this to use GE link update with gigabit PHY.
1174 Define this if FTGMAC100 is connected to gigabit PHY.
1175 If your system has 10/100 PHY only, it might not occur
1176 wrong behavior. Because PHY usually return timeout or
1177 useless data when polling gigabit status and gigabit
1178 control registers. This behavior won't affect the
1179 correctnessof 10/100 link speed update.
1182 Support for SMSC's LAN911x and LAN921x chips
1185 Define this to hold the physical address
1186 of the device (I/O space)
1188 CONFIG_SMC911X_32_BIT
1189 Define this if data bus is 32 bits
1191 CONFIG_SMC911X_16_BIT
1192 Define this if data bus is 16 bits. If your processor
1193 automatically converts one 32 bit word to two 16 bit
1194 words you may also try CONFIG_SMC911X_32_BIT.
1197 Support for Renesas on-chip Ethernet controller
1199 CONFIG_SH_ETHER_USE_PORT
1200 Define the number of ports to be used
1202 CONFIG_SH_ETHER_PHY_ADDR
1203 Define the ETH PHY's address
1205 CONFIG_SH_ETHER_CACHE_WRITEBACK
1206 If this option is set, the driver enables cache flush.
1210 Support TPM devices.
1213 Support for i2c bus TPM devices. Only one device
1214 per system is supported at this time.
1216 CONFIG_TPM_TIS_I2C_BUS_NUMBER
1217 Define the the i2c bus number for the TPM device
1219 CONFIG_TPM_TIS_I2C_SLAVE_ADDRESS
1220 Define the TPM's address on the i2c bus
1222 CONFIG_TPM_TIS_I2C_BURST_LIMITATION
1223 Define the burst count bytes upper limit
1225 CONFIG_TPM_ATMEL_TWI
1226 Support for Atmel TWI TPM device. Requires I2C support.
1229 Support for generic parallel port TPM devices. Only one device
1230 per system is supported at this time.
1232 CONFIG_TPM_TIS_BASE_ADDRESS
1233 Base address where the generic TPM device is mapped
1234 to. Contemporary x86 systems usually map it at
1238 Add tpm monitor functions.
1239 Requires CONFIG_TPM. If CONFIG_TPM_AUTH_SESSIONS is set, also
1240 provides monitor access to authorized functions.
1243 Define this to enable the TPM support library which provides
1244 functional interfaces to some TPM commands.
1245 Requires support for a TPM device.
1247 CONFIG_TPM_AUTH_SESSIONS
1248 Define this to enable authorized functions in the TPM library.
1249 Requires CONFIG_TPM and CONFIG_SHA1.
1252 At the moment only the UHCI host controller is
1253 supported (PIP405, MIP405, MPC5200); define
1254 CONFIG_USB_UHCI to enable it.
1255 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
1256 and define CONFIG_USB_STORAGE to enable the USB
1259 Supported are USB Keyboards and USB Floppy drives
1261 MPC5200 USB requires additional defines:
1263 for 528 MHz Clock: 0x0001bbbb
1267 for differential drivers: 0x00001000
1268 for single ended drivers: 0x00005000
1269 for differential drivers on PSC3: 0x00000100
1270 for single ended drivers on PSC3: 0x00004100
1271 CONFIG_SYS_USB_EVENT_POLL
1272 May be defined to allow interrupt polling
1273 instead of using asynchronous interrupts
1275 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the
1276 txfilltuning field in the EHCI controller on reset.
1278 CONFIG_USB_HUB_MIN_POWER_ON_DELAY defines the minimum
1279 interval for usb hub power-on delay.(minimum 100msec)
1282 Define the below if you wish to use the USB console.
1283 Once firmware is rebuilt from a serial console issue the
1284 command "setenv stdin usbtty; setenv stdout usbtty" and
1285 attach your USB cable. The Unix command "dmesg" should print
1286 it has found a new device. The environment variable usbtty
1287 can be set to gserial or cdc_acm to enable your device to
1288 appear to a USB host as a Linux gserial device or a
1289 Common Device Class Abstract Control Model serial device.
1290 If you select usbtty = gserial you should be able to enumerate
1292 # modprobe usbserial vendor=0xVendorID product=0xProductID
1293 else if using cdc_acm, simply setting the environment
1294 variable usbtty to be cdc_acm should suffice. The following
1295 might be defined in YourBoardName.h
1298 Define this to build a UDC device
1301 Define this to have a tty type of device available to
1302 talk to the UDC device
1305 Define this to enable the high speed support for usb
1306 device and usbtty. If this feature is enabled, a routine
1307 int is_usbd_high_speed(void)
1308 also needs to be defined by the driver to dynamically poll
1309 whether the enumeration has succeded at high speed or full
1312 CONFIG_SYS_CONSOLE_IS_IN_ENV
1313 Define this if you want stdin, stdout &/or stderr to
1317 CONFIG_SYS_USB_EXTC_CLK 0xBLAH
1318 Derive USB clock from external clock "blah"
1319 - CONFIG_SYS_USB_EXTC_CLK 0x02
1321 CONFIG_SYS_USB_BRG_CLK 0xBLAH
1322 Derive USB clock from brgclk
1323 - CONFIG_SYS_USB_BRG_CLK 0x04
1325 If you have a USB-IF assigned VendorID then you may wish to
1326 define your own vendor specific values either in BoardName.h
1327 or directly in usbd_vendor_info.h. If you don't define
1328 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
1329 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
1330 should pretend to be a Linux device to it's target host.
1332 CONFIG_USBD_MANUFACTURER
1333 Define this string as the name of your company for
1334 - CONFIG_USBD_MANUFACTURER "my company"
1336 CONFIG_USBD_PRODUCT_NAME
1337 Define this string as the name of your product
1338 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
1340 CONFIG_USBD_VENDORID
1341 Define this as your assigned Vendor ID from the USB
1342 Implementors Forum. This *must* be a genuine Vendor ID
1343 to avoid polluting the USB namespace.
1344 - CONFIG_USBD_VENDORID 0xFFFF
1346 CONFIG_USBD_PRODUCTID
1347 Define this as the unique Product ID
1349 - CONFIG_USBD_PRODUCTID 0xFFFF
1351 - ULPI Layer Support:
1352 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via
1353 the generic ULPI layer. The generic layer accesses the ULPI PHY
1354 via the platform viewport, so you need both the genric layer and
1355 the viewport enabled. Currently only Chipidea/ARC based
1356 viewport is supported.
1357 To enable the ULPI layer support, define CONFIG_USB_ULPI and
1358 CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
1359 If your ULPI phy needs a different reference clock than the
1360 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to
1361 the appropriate value in Hz.
1364 The MMC controller on the Intel PXA is supported. To
1365 enable this define CONFIG_MMC. The MMC can be
1366 accessed from the boot prompt by mapping the device
1367 to physical memory similar to flash. Command line is
1368 enabled with CONFIG_CMD_MMC. The MMC driver also works with
1369 the FAT fs. This is enabled with CONFIG_CMD_FAT.
1372 Support for Renesas on-chip MMCIF controller
1374 CONFIG_SH_MMCIF_ADDR
1375 Define the base address of MMCIF registers
1378 Define the clock frequency for MMCIF
1380 - USB Device Firmware Update (DFU) class support:
1382 This enables the USB portion of the DFU USB class
1385 This enables the command "dfu" which is used to have
1386 U-Boot create a DFU class device via USB. This command
1387 requires that the "dfu_alt_info" environment variable be
1388 set and define the alt settings to expose to the host.
1391 This enables support for exposing (e)MMC devices via DFU.
1394 This enables support for exposing NAND devices via DFU.
1396 CONFIG_SYS_DFU_DATA_BUF_SIZE
1397 Dfu transfer uses a buffer before writing data to the
1398 raw storage device. Make the size (in bytes) of this buffer
1399 configurable. The size of this buffer is also configurable
1400 through the "dfu_bufsiz" environment variable.
1402 CONFIG_SYS_DFU_MAX_FILE_SIZE
1403 When updating files rather than the raw storage device,
1404 we use a static buffer to copy the file into and then write
1405 the buffer once we've been given the whole file. Define
1406 this to the maximum filesize (in bytes) for the buffer.
1407 Default is 4 MiB if undefined.
1409 - Journaling Flash filesystem support:
1410 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
1411 CONFIG_JFFS2_NAND_DEV
1412 Define these for a default partition on a NAND device
1414 CONFIG_SYS_JFFS2_FIRST_SECTOR,
1415 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
1416 Define these for a default partition on a NOR device
1418 CONFIG_SYS_JFFS_CUSTOM_PART
1419 Define this to create an own partition. You have to provide a
1420 function struct part_info* jffs2_part_info(int part_num)
1422 If you define only one JFFS2 partition you may also want to
1423 #define CONFIG_SYS_JFFS_SINGLE_PART 1
1424 to disable the command chpart. This is the default when you
1425 have not defined a custom partition
1427 - FAT(File Allocation Table) filesystem write function support:
1430 Define this to enable support for saving memory data as a
1431 file in FAT formatted partition.
1433 This will also enable the command "fatwrite" enabling the
1434 user to write files to FAT.
1436 CBFS (Coreboot Filesystem) support
1439 Define this to enable support for reading from a Coreboot
1440 filesystem. Available commands are cbfsinit, cbfsinfo, cbfsls
1446 Define this to enable standard (PC-Style) keyboard
1450 Standard PC keyboard driver with US (is default) and
1451 GERMAN key layout (switch via environment 'keymap=de') support.
1452 Export function i8042_kbd_init, i8042_tstc and i8042_getc
1453 for cfb_console. Supports cursor blinking.
1456 Enables a Chrome OS keyboard using the CROS_EC interface.
1457 This uses CROS_EC to communicate with a second microcontroller
1458 which provides key scans on request.
1463 Define this to enable video support (for output to
1466 CONFIG_VIDEO_CT69000
1468 Enable Chips & Technologies 69000 Video chip
1470 CONFIG_VIDEO_SMI_LYNXEM
1471 Enable Silicon Motion SMI 712/710/810 Video chip. The
1472 video output is selected via environment 'videoout'
1473 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
1476 For the CT69000 and SMI_LYNXEM drivers, videomode is
1477 selected via environment 'videomode'. Two different ways
1479 - "videomode=num" 'num' is a standard LiLo mode numbers.
1480 Following standard modes are supported (* is default):
1482 Colors 640x480 800x600 1024x768 1152x864 1280x1024
1483 -------------+---------------------------------------------
1484 8 bits | 0x301* 0x303 0x305 0x161 0x307
1485 15 bits | 0x310 0x313 0x316 0x162 0x319
1486 16 bits | 0x311 0x314 0x317 0x163 0x31A
1487 24 bits | 0x312 0x315 0x318 ? 0x31B
1488 -------------+---------------------------------------------
1489 (i.e. setenv videomode 317; saveenv; reset;)
1491 - "videomode=bootargs" all the video parameters are parsed
1492 from the bootargs. (See drivers/video/videomodes.c)
1495 CONFIG_VIDEO_SED13806
1496 Enable Epson SED13806 driver. This driver supports 8bpp
1497 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
1498 or CONFIG_VIDEO_SED13806_16BPP
1501 Enable the Freescale DIU video driver. Reference boards for
1502 SOCs that have a DIU should define this macro to enable DIU
1503 support, and should also define these other macros:
1509 CONFIG_VIDEO_SW_CURSOR
1510 CONFIG_VGA_AS_SINGLE_DEVICE
1512 CONFIG_VIDEO_BMP_LOGO
1514 The DIU driver will look for the 'video-mode' environment
1515 variable, and if defined, enable the DIU as a console during
1516 boot. See the documentation file README.video for a
1517 description of this variable.
1521 Enable the VGA video / BIOS for x86. The alternative if you
1522 are using coreboot is to use the coreboot frame buffer
1529 Define this to enable a custom keyboard support.
1530 This simply calls drv_keyboard_init() which must be
1531 defined in your board-specific files.
1532 The only board using this so far is RBC823.
1534 - LCD Support: CONFIG_LCD
1536 Define this to enable LCD support (for output to LCD
1537 display); also select one of the supported displays
1538 by defining one of these:
1542 HITACHI TX09D70VM1CCA, 3.5", 240x320.
1544 CONFIG_NEC_NL6448AC33:
1546 NEC NL6448AC33-18. Active, color, single scan.
1548 CONFIG_NEC_NL6448BC20
1550 NEC NL6448BC20-08. 6.5", 640x480.
1551 Active, color, single scan.
1553 CONFIG_NEC_NL6448BC33_54
1555 NEC NL6448BC33-54. 10.4", 640x480.
1556 Active, color, single scan.
1560 Sharp 320x240. Active, color, single scan.
1561 It isn't 16x9, and I am not sure what it is.
1563 CONFIG_SHARP_LQ64D341
1565 Sharp LQ64D341 display, 640x480.
1566 Active, color, single scan.
1570 HLD1045 display, 640x480.
1571 Active, color, single scan.
1575 Optrex CBL50840-2 NF-FW 99 22 M5
1577 Hitachi LMG6912RPFC-00T
1581 320x240. Black & white.
1583 Normally display is black on white background; define
1584 CONFIG_SYS_WHITE_ON_BLACK to get it inverted.
1586 CONFIG_LCD_ALIGNMENT
1588 Normally the LCD is page-aligned (tyically 4KB). If this is
1589 defined then the LCD will be aligned to this value instead.
1590 For ARM it is sometimes useful to use MMU_SECTION_SIZE
1591 here, since it is cheaper to change data cache settings on
1592 a per-section basis.
1594 CONFIG_CONSOLE_SCROLL_LINES
1596 When the console need to be scrolled, this is the number of
1597 lines to scroll by. It defaults to 1. Increasing this makes
1598 the console jump but can help speed up operation when scrolling
1603 Support drawing of RLE8-compressed bitmaps on the LCD.
1607 Enables an 'i2c edid' command which can read EDID
1608 information over I2C from an attached LCD display.
1610 - Splash Screen Support: CONFIG_SPLASH_SCREEN
1612 If this option is set, the environment is checked for
1613 a variable "splashimage". If found, the usual display
1614 of logo, copyright and system information on the LCD
1615 is suppressed and the BMP image at the address
1616 specified in "splashimage" is loaded instead. The
1617 console is redirected to the "nulldev", too. This
1618 allows for a "silent" boot where a splash screen is
1619 loaded very quickly after power-on.
1621 CONFIG_SPLASHIMAGE_GUARD
1623 If this option is set, then U-Boot will prevent the environment
1624 variable "splashimage" from being set to a problematic address
1625 (see README.displaying-bmps and README.arm-unaligned-accesses).
1626 This option is useful for targets where, due to alignment
1627 restrictions, an improperly aligned BMP image will cause a data
1628 abort. If you think you will not have problems with unaligned
1629 accesses (for example because your toolchain prevents them)
1630 there is no need to set this option.
1632 CONFIG_SPLASH_SCREEN_ALIGN
1634 If this option is set the splash image can be freely positioned
1635 on the screen. Environment variable "splashpos" specifies the
1636 position as "x,y". If a positive number is given it is used as
1637 number of pixel from left/top. If a negative number is given it
1638 is used as number of pixel from right/bottom. You can also
1639 specify 'm' for centering the image.
1642 setenv splashpos m,m
1643 => image at center of screen
1645 setenv splashpos 30,20
1646 => image at x = 30 and y = 20
1648 setenv splashpos -10,m
1649 => vertically centered image
1650 at x = dspWidth - bmpWidth - 9
1652 - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
1654 If this option is set, additionally to standard BMP
1655 images, gzipped BMP images can be displayed via the
1656 splashscreen support or the bmp command.
1658 - Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
1660 If this option is set, 8-bit RLE compressed BMP images
1661 can be displayed via the splashscreen support or the
1664 - Do compresssing for memory range:
1667 If this option is set, it would use zlib deflate method
1668 to compress the specified memory at its best effort.
1670 - Compression support:
1673 If this option is set, support for bzip2 compressed
1674 images is included. If not, only uncompressed and gzip
1675 compressed images are supported.
1677 NOTE: the bzip2 algorithm requires a lot of RAM, so
1678 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
1683 If this option is set, support for lzma compressed
1686 Note: The LZMA algorithm adds between 2 and 4KB of code and it
1687 requires an amount of dynamic memory that is given by the
1690 (1846 + 768 << (lc + lp)) * sizeof(uint16)
1692 Where lc and lp stand for, respectively, Literal context bits
1693 and Literal pos bits.
1695 This value is upper-bounded by 14MB in the worst case. Anyway,
1696 for a ~4MB large kernel image, we have lc=3 and lp=0 for a
1697 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is
1698 a very small buffer.
1700 Use the lzmainfo tool to determinate the lc and lp values and
1701 then calculate the amount of needed dynamic memory (ensuring
1702 the appropriate CONFIG_SYS_MALLOC_LEN value).
1707 The address of PHY on MII bus.
1709 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1711 The clock frequency of the MII bus
1715 If this option is set, support for speed/duplex
1716 detection of gigabit PHY is included.
1718 CONFIG_PHY_RESET_DELAY
1720 Some PHY like Intel LXT971A need extra delay after
1721 reset before any MII register access is possible.
1722 For such PHY, set this option to the usec delay
1723 required. (minimum 300usec for LXT971A)
1725 CONFIG_PHY_CMD_DELAY (ppc4xx)
1727 Some PHY like Intel LXT971A need extra delay after
1728 command issued before MII status register can be read
1738 Define a default value for Ethernet address to use
1739 for the respective Ethernet interface, in case this
1740 is not determined automatically.
1745 Define a default value for the IP address to use for
1746 the default Ethernet interface, in case this is not
1747 determined through e.g. bootp.
1748 (Environment variable "ipaddr")
1750 - Server IP address:
1753 Defines a default value for the IP address of a TFTP
1754 server to contact when using the "tftboot" command.
1755 (Environment variable "serverip")
1757 CONFIG_KEEP_SERVERADDR
1759 Keeps the server's MAC address, in the env 'serveraddr'
1760 for passing to bootargs (like Linux's netconsole option)
1762 - Gateway IP address:
1765 Defines a default value for the IP address of the
1766 default router where packets to other networks are
1768 (Environment variable "gatewayip")
1773 Defines a default value for the subnet mask (or
1774 routing prefix) which is used to determine if an IP
1775 address belongs to the local subnet or needs to be
1776 forwarded through a router.
1777 (Environment variable "netmask")
1779 - Multicast TFTP Mode:
1782 Defines whether you want to support multicast TFTP as per
1783 rfc-2090; for example to work with atftp. Lets lots of targets
1784 tftp down the same boot image concurrently. Note: the Ethernet
1785 driver in use must provide a function: mcast() to join/leave a
1788 - BOOTP Recovery Mode:
1789 CONFIG_BOOTP_RANDOM_DELAY
1791 If you have many targets in a network that try to
1792 boot using BOOTP, you may want to avoid that all
1793 systems send out BOOTP requests at precisely the same
1794 moment (which would happen for instance at recovery
1795 from a power failure, when all systems will try to
1796 boot, thus flooding the BOOTP server. Defining
1797 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1798 inserted before sending out BOOTP requests. The
1799 following delays are inserted then:
1801 1st BOOTP request: delay 0 ... 1 sec
1802 2nd BOOTP request: delay 0 ... 2 sec
1803 3rd BOOTP request: delay 0 ... 4 sec
1805 BOOTP requests: delay 0 ... 8 sec
1807 - DHCP Advanced Options:
1808 You can fine tune the DHCP functionality by defining
1809 CONFIG_BOOTP_* symbols:
1811 CONFIG_BOOTP_SUBNETMASK
1812 CONFIG_BOOTP_GATEWAY
1813 CONFIG_BOOTP_HOSTNAME
1814 CONFIG_BOOTP_NISDOMAIN
1815 CONFIG_BOOTP_BOOTPATH
1816 CONFIG_BOOTP_BOOTFILESIZE
1819 CONFIG_BOOTP_SEND_HOSTNAME
1820 CONFIG_BOOTP_NTPSERVER
1821 CONFIG_BOOTP_TIMEOFFSET
1822 CONFIG_BOOTP_VENDOREX
1823 CONFIG_BOOTP_MAY_FAIL
1825 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
1826 environment variable, not the BOOTP server.
1828 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found
1829 after the configured retry count, the call will fail
1830 instead of starting over. This can be used to fail over
1831 to Link-local IP address configuration if the DHCP server
1834 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
1835 serverip from a DHCP server, it is possible that more
1836 than one DNS serverip is offered to the client.
1837 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1838 serverip will be stored in the additional environment
1839 variable "dnsip2". The first DNS serverip is always
1840 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
1843 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1844 to do a dynamic update of a DNS server. To do this, they
1845 need the hostname of the DHCP requester.
1846 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
1847 of the "hostname" environment variable is passed as
1848 option 12 to the DHCP server.
1850 CONFIG_BOOTP_DHCP_REQUEST_DELAY
1852 A 32bit value in microseconds for a delay between
1853 receiving a "DHCP Offer" and sending the "DHCP Request".
1854 This fixes a problem with certain DHCP servers that don't
1855 respond 100% of the time to a "DHCP request". E.g. On an
1856 AT91RM9200 processor running at 180MHz, this delay needed
1857 to be *at least* 15,000 usec before a Windows Server 2003
1858 DHCP server would reply 100% of the time. I recommend at
1859 least 50,000 usec to be safe. The alternative is to hope
1860 that one of the retries will be successful but note that
1861 the DHCP timeout and retry process takes a longer than
1864 - Link-local IP address negotiation:
1865 Negotiate with other link-local clients on the local network
1866 for an address that doesn't require explicit configuration.
1867 This is especially useful if a DHCP server cannot be guaranteed
1868 to exist in all environments that the device must operate.
1870 See doc/README.link-local for more information.
1873 CONFIG_CDP_DEVICE_ID
1875 The device id used in CDP trigger frames.
1877 CONFIG_CDP_DEVICE_ID_PREFIX
1879 A two character string which is prefixed to the MAC address
1884 A printf format string which contains the ascii name of
1885 the port. Normally is set to "eth%d" which sets
1886 eth0 for the first Ethernet, eth1 for the second etc.
1888 CONFIG_CDP_CAPABILITIES
1890 A 32bit integer which indicates the device capabilities;
1891 0x00000010 for a normal host which does not forwards.
1895 An ascii string containing the version of the software.
1899 An ascii string containing the name of the platform.
1903 A 32bit integer sent on the trigger.
1905 CONFIG_CDP_POWER_CONSUMPTION
1907 A 16bit integer containing the power consumption of the
1908 device in .1 of milliwatts.
1910 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1912 A byte containing the id of the VLAN.
1914 - Status LED: CONFIG_STATUS_LED
1916 Several configurations allow to display the current
1917 status using a LED. For instance, the LED will blink
1918 fast while running U-Boot code, stop blinking as
1919 soon as a reply to a BOOTP request was received, and
1920 start blinking slow once the Linux kernel is running
1921 (supported by a status LED driver in the Linux
1922 kernel). Defining CONFIG_STATUS_LED enables this
1925 - CAN Support: CONFIG_CAN_DRIVER
1927 Defining CONFIG_CAN_DRIVER enables CAN driver support
1928 on those systems that support this (optional)
1929 feature, like the TQM8xxL modules.
1931 - I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C
1933 These enable I2C serial bus commands. Defining either of
1934 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will
1935 include the appropriate I2C driver for the selected CPU.
1937 This will allow you to use i2c commands at the u-boot
1938 command line (as long as you set CONFIG_CMD_I2C in
1939 CONFIG_COMMANDS) and communicate with i2c based realtime
1940 clock chips. See common/cmd_i2c.c for a description of the
1941 command line interface.
1943 CONFIG_HARD_I2C selects a hardware I2C controller.
1945 CONFIG_SOFT_I2C configures u-boot to use a software (aka
1946 bit-banging) driver instead of CPM or similar hardware
1949 There are several other quantities that must also be
1950 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C.
1952 In both cases you will need to define CONFIG_SYS_I2C_SPEED
1953 to be the frequency (in Hz) at which you wish your i2c bus
1954 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie
1955 the CPU's i2c node address).
1957 Now, the u-boot i2c code for the mpc8xx
1958 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node
1959 and so its address should therefore be cleared to 0 (See,
1960 eg, MPC823e User's Manual p.16-473). So, set
1961 CONFIG_SYS_I2C_SLAVE to 0.
1963 CONFIG_SYS_I2C_INIT_MPC5XXX
1965 When a board is reset during an i2c bus transfer
1966 chips might think that the current transfer is still
1967 in progress. Reset the slave devices by sending start
1968 commands until the slave device responds.
1970 That's all that's required for CONFIG_HARD_I2C.
1972 If you use the software i2c interface (CONFIG_SOFT_I2C)
1973 then the following macros need to be defined (examples are
1974 from include/configs/lwmon.h):
1978 (Optional). Any commands necessary to enable the I2C
1979 controller or configure ports.
1981 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
1985 (Only for MPC8260 CPU). The I/O port to use (the code
1986 assumes both bits are on the same port). Valid values
1987 are 0..3 for ports A..D.
1991 The code necessary to make the I2C data line active
1992 (driven). If the data line is open collector, this
1995 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
1999 The code necessary to make the I2C data line tri-stated
2000 (inactive). If the data line is open collector, this
2003 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
2007 Code that returns true if the I2C data line is high,
2010 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
2014 If <bit> is true, sets the I2C data line high. If it
2015 is false, it clears it (low).
2017 eg: #define I2C_SDA(bit) \
2018 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
2019 else immr->im_cpm.cp_pbdat &= ~PB_SDA
2023 If <bit> is true, sets the I2C clock line high. If it
2024 is false, it clears it (low).
2026 eg: #define I2C_SCL(bit) \
2027 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
2028 else immr->im_cpm.cp_pbdat &= ~PB_SCL
2032 This delay is invoked four times per clock cycle so this
2033 controls the rate of data transfer. The data rate thus
2034 is 1 / (I2C_DELAY * 4). Often defined to be something
2037 #define I2C_DELAY udelay(2)
2039 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
2041 If your arch supports the generic GPIO framework (asm/gpio.h),
2042 then you may alternatively define the two GPIOs that are to be
2043 used as SCL / SDA. Any of the previous I2C_xxx macros will
2044 have GPIO-based defaults assigned to them as appropriate.
2046 You should define these to the GPIO value as given directly to
2047 the generic GPIO functions.
2049 CONFIG_SYS_I2C_INIT_BOARD
2051 When a board is reset during an i2c bus transfer
2052 chips might think that the current transfer is still
2053 in progress. On some boards it is possible to access
2054 the i2c SCLK line directly, either by using the
2055 processor pin as a GPIO or by having a second pin
2056 connected to the bus. If this option is defined a
2057 custom i2c_init_board() routine in boards/xxx/board.c
2058 is run early in the boot sequence.
2060 CONFIG_SYS_I2C_BOARD_LATE_INIT
2062 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is
2063 defined a custom i2c_board_late_init() routine in
2064 boards/xxx/board.c is run AFTER the operations in i2c_init()
2065 is completed. This callpoint can be used to unreset i2c bus
2066 using CPU i2c controller register accesses for CPUs whose i2c
2067 controller provide such a method. It is called at the end of
2068 i2c_init() to allow i2c_init operations to setup the i2c bus
2069 controller on the CPU (e.g. setting bus speed & slave address).
2071 CONFIG_I2CFAST (PPC405GP|PPC405EP only)
2073 This option enables configuration of bi_iic_fast[] flags
2074 in u-boot bd_info structure based on u-boot environment
2075 variable "i2cfast". (see also i2cfast)
2077 CONFIG_I2C_MULTI_BUS
2079 This option allows the use of multiple I2C buses, each of which
2080 must have a controller. At any point in time, only one bus is
2081 active. To switch to a different bus, use the 'i2c dev' command.
2082 Note that bus numbering is zero-based.
2084 CONFIG_SYS_I2C_NOPROBES
2086 This option specifies a list of I2C devices that will be skipped
2087 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
2088 is set, specify a list of bus-device pairs. Otherwise, specify
2089 a 1D array of device addresses
2092 #undef CONFIG_I2C_MULTI_BUS
2093 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
2095 will skip addresses 0x50 and 0x68 on a board with one I2C bus
2097 #define CONFIG_I2C_MULTI_BUS
2098 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
2100 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
2102 CONFIG_SYS_SPD_BUS_NUM
2104 If defined, then this indicates the I2C bus number for DDR SPD.
2105 If not defined, then U-Boot assumes that SPD is on I2C bus 0.
2107 CONFIG_SYS_RTC_BUS_NUM
2109 If defined, then this indicates the I2C bus number for the RTC.
2110 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
2112 CONFIG_SYS_DTT_BUS_NUM
2114 If defined, then this indicates the I2C bus number for the DTT.
2115 If not defined, then U-Boot assumes that DTT is on I2C bus 0.
2117 CONFIG_SYS_I2C_DTT_ADDR:
2119 If defined, specifies the I2C address of the DTT device.
2120 If not defined, then U-Boot uses predefined value for
2121 specified DTT device.
2125 Define this option if you want to use Freescale's I2C driver in
2126 drivers/i2c/fsl_i2c.c.
2130 Define this option if you have I2C devices reached over 1 .. n
2131 I2C Muxes like the pca9544a. This option addes a new I2C
2132 Command "i2c bus [muxtype:muxaddr:muxchannel]" which adds a
2133 new I2C Bus to the existing I2C Busses. If you select the
2134 new Bus with "i2c dev", u-bbot sends first the commandos for
2135 the muxes to activate this new "bus".
2137 CONFIG_I2C_MULTI_BUS must be also defined, to use this
2141 Adding a new I2C Bus reached over 2 pca9544a muxes
2142 The First mux with address 70 and channel 6
2143 The Second mux with address 71 and channel 4
2145 => i2c bus pca9544a:70:6:pca9544a:71:4
2147 Use the "i2c bus" command without parameter, to get a list
2148 of I2C Busses with muxes:
2151 Busses reached over muxes:
2153 reached over Mux(es):
2156 reached over Mux(es):
2161 If you now switch to the new I2C Bus 3 with "i2c dev 3"
2162 u-boot first sends the command to the mux@70 to enable
2163 channel 6, and then the command to the mux@71 to enable
2166 After that, you can use the "normal" i2c commands as
2167 usual to communicate with your I2C devices behind
2170 This option is actually implemented for the bitbanging
2171 algorithm in common/soft_i2c.c and for the Hardware I2C
2172 Bus on the MPC8260. But it should be not so difficult
2173 to add this option to other architectures.
2175 CONFIG_SOFT_I2C_READ_REPEATED_START
2177 defining this will force the i2c_read() function in
2178 the soft_i2c driver to perform an I2C repeated start
2179 between writing the address pointer and reading the
2180 data. If this define is omitted the default behaviour
2181 of doing a stop-start sequence will be used. Most I2C
2182 devices can use either method, but some require one or
2185 - SPI Support: CONFIG_SPI
2187 Enables SPI driver (so far only tested with
2188 SPI EEPROM, also an instance works with Crystal A/D and
2189 D/As on the SACSng board)
2193 Enables the driver for SPI controller on SuperH. Currently
2194 only SH7757 is supported.
2198 Enables extended (16-bit) SPI EEPROM addressing.
2199 (symmetrical to CONFIG_I2C_X)
2203 Enables a software (bit-bang) SPI driver rather than
2204 using hardware support. This is a general purpose
2205 driver that only requires three general I/O port pins
2206 (two outputs, one input) to function. If this is
2207 defined, the board configuration must define several
2208 SPI configuration items (port pins to use, etc). For
2209 an example, see include/configs/sacsng.h.
2213 Enables a hardware SPI driver for general-purpose reads
2214 and writes. As with CONFIG_SOFT_SPI, the board configuration
2215 must define a list of chip-select function pointers.
2216 Currently supported on some MPC8xxx processors. For an
2217 example, see include/configs/mpc8349emds.h.
2221 Enables the driver for the SPI controllers on i.MX and MXC
2222 SoCs. Currently i.MX31/35/51 are supported.
2224 - FPGA Support: CONFIG_FPGA
2226 Enables FPGA subsystem.
2228 CONFIG_FPGA_<vendor>
2230 Enables support for specific chip vendors.
2233 CONFIG_FPGA_<family>
2235 Enables support for FPGA family.
2236 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
2240 Specify the number of FPGA devices to support.
2242 CONFIG_SYS_FPGA_PROG_FEEDBACK
2244 Enable printing of hash marks during FPGA configuration.
2246 CONFIG_SYS_FPGA_CHECK_BUSY
2248 Enable checks on FPGA configuration interface busy
2249 status by the configuration function. This option
2250 will require a board or device specific function to
2255 If defined, a function that provides delays in the FPGA
2256 configuration driver.
2258 CONFIG_SYS_FPGA_CHECK_CTRLC
2259 Allow Control-C to interrupt FPGA configuration
2261 CONFIG_SYS_FPGA_CHECK_ERROR
2263 Check for configuration errors during FPGA bitfile
2264 loading. For example, abort during Virtex II
2265 configuration if the INIT_B line goes low (which
2266 indicated a CRC error).
2268 CONFIG_SYS_FPGA_WAIT_INIT
2270 Maximum time to wait for the INIT_B line to deassert
2271 after PROB_B has been deasserted during a Virtex II
2272 FPGA configuration sequence. The default time is 500
2275 CONFIG_SYS_FPGA_WAIT_BUSY
2277 Maximum time to wait for BUSY to deassert during
2278 Virtex II FPGA configuration. The default is 5 ms.
2280 CONFIG_SYS_FPGA_WAIT_CONFIG
2282 Time to wait after FPGA configuration. The default is
2285 - Configuration Management:
2288 If defined, this string will be added to the U-Boot
2289 version information (U_BOOT_VERSION)
2291 - Vendor Parameter Protection:
2293 U-Boot considers the values of the environment
2294 variables "serial#" (Board Serial Number) and
2295 "ethaddr" (Ethernet Address) to be parameters that
2296 are set once by the board vendor / manufacturer, and
2297 protects these variables from casual modification by
2298 the user. Once set, these variables are read-only,
2299 and write or delete attempts are rejected. You can
2300 change this behaviour:
2302 If CONFIG_ENV_OVERWRITE is #defined in your config
2303 file, the write protection for vendor parameters is
2304 completely disabled. Anybody can change or delete
2307 Alternatively, if you #define _both_ CONFIG_ETHADDR
2308 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
2309 Ethernet address is installed in the environment,
2310 which can be changed exactly ONCE by the user. [The
2311 serial# is unaffected by this, i. e. it remains
2314 The same can be accomplished in a more flexible way
2315 for any variable by configuring the type of access
2316 to allow for those variables in the ".flags" variable
2317 or define CONFIG_ENV_FLAGS_LIST_STATIC.
2322 Define this variable to enable the reservation of
2323 "protected RAM", i. e. RAM which is not overwritten
2324 by U-Boot. Define CONFIG_PRAM to hold the number of
2325 kB you want to reserve for pRAM. You can overwrite
2326 this default value by defining an environment
2327 variable "pram" to the number of kB you want to
2328 reserve. Note that the board info structure will
2329 still show the full amount of RAM. If pRAM is
2330 reserved, a new environment variable "mem" will
2331 automatically be defined to hold the amount of
2332 remaining RAM in a form that can be passed as boot
2333 argument to Linux, for instance like that:
2335 setenv bootargs ... mem=\${mem}
2338 This way you can tell Linux not to use this memory,
2339 either, which results in a memory region that will
2340 not be affected by reboots.
2342 *WARNING* If your board configuration uses automatic
2343 detection of the RAM size, you must make sure that
2344 this memory test is non-destructive. So far, the
2345 following board configurations are known to be
2348 IVMS8, IVML24, SPD8xx, TQM8xxL,
2349 HERMES, IP860, RPXlite, LWMON,
2352 - Access to physical memory region (> 4GB)
2353 Some basic support is provided for operations on memory not
2354 normally accessible to U-Boot - e.g. some architectures
2355 support access to more than 4GB of memory on 32-bit
2356 machines using physical address extension or similar.
2357 Define CONFIG_PHYSMEM to access this basic support, which
2358 currently only supports clearing the memory.
2363 Define this variable to stop the system in case of a
2364 fatal error, so that you have to reset it manually.
2365 This is probably NOT a good idea for an embedded
2366 system where you want the system to reboot
2367 automatically as fast as possible, but it may be
2368 useful during development since you can try to debug
2369 the conditions that lead to the situation.
2371 CONFIG_NET_RETRY_COUNT
2373 This variable defines the number of retries for
2374 network operations like ARP, RARP, TFTP, or BOOTP
2375 before giving up the operation. If not defined, a
2376 default value of 5 is used.
2380 Timeout waiting for an ARP reply in milliseconds.
2384 Timeout in milliseconds used in NFS protocol.
2385 If you encounter "ERROR: Cannot umount" in nfs command,
2386 try longer timeout such as
2387 #define CONFIG_NFS_TIMEOUT 10000UL
2389 - Command Interpreter:
2390 CONFIG_AUTO_COMPLETE
2392 Enable auto completion of commands using TAB.
2394 Note that this feature has NOT been implemented yet
2395 for the "hush" shell.
2398 CONFIG_SYS_HUSH_PARSER
2400 Define this variable to enable the "hush" shell (from
2401 Busybox) as command line interpreter, thus enabling
2402 powerful command line syntax like
2403 if...then...else...fi conditionals or `&&' and '||'
2404 constructs ("shell scripts").
2406 If undefined, you get the old, much simpler behaviour
2407 with a somewhat smaller memory footprint.
2410 CONFIG_SYS_PROMPT_HUSH_PS2
2412 This defines the secondary prompt string, which is
2413 printed when the command interpreter needs more input
2414 to complete a command. Usually "> ".
2418 In the current implementation, the local variables
2419 space and global environment variables space are
2420 separated. Local variables are those you define by
2421 simply typing `name=value'. To access a local
2422 variable later on, you have write `$name' or
2423 `${name}'; to execute the contents of a variable
2424 directly type `$name' at the command prompt.
2426 Global environment variables are those you use
2427 setenv/printenv to work with. To run a command stored
2428 in such a variable, you need to use the run command,
2429 and you must not use the '$' sign to access them.
2431 To store commands and special characters in a
2432 variable, please use double quotation marks
2433 surrounding the whole text of the variable, instead
2434 of the backslashes before semicolons and special
2437 - Commandline Editing and History:
2438 CONFIG_CMDLINE_EDITING
2440 Enable editing and History functions for interactive
2441 commandline input operations
2443 - Default Environment:
2444 CONFIG_EXTRA_ENV_SETTINGS
2446 Define this to contain any number of null terminated
2447 strings (variable = value pairs) that will be part of
2448 the default environment compiled into the boot image.
2450 For example, place something like this in your
2451 board's config file:
2453 #define CONFIG_EXTRA_ENV_SETTINGS \
2457 Warning: This method is based on knowledge about the
2458 internal format how the environment is stored by the
2459 U-Boot code. This is NOT an official, exported
2460 interface! Although it is unlikely that this format
2461 will change soon, there is no guarantee either.
2462 You better know what you are doing here.
2464 Note: overly (ab)use of the default environment is
2465 discouraged. Make sure to check other ways to preset
2466 the environment like the "source" command or the
2469 CONFIG_ENV_VARS_UBOOT_CONFIG
2471 Define this in order to add variables describing the
2472 U-Boot build configuration to the default environment.
2473 These will be named arch, cpu, board, vendor, and soc.
2475 Enabling this option will cause the following to be defined:
2483 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG
2485 Define this in order to add variables describing certain
2486 run-time determined information about the hardware to the
2487 environment. These will be named board_name, board_rev.
2489 CONFIG_DELAY_ENVIRONMENT
2491 Normally the environment is loaded when the board is
2492 intialised so that it is available to U-Boot. This inhibits
2493 that so that the environment is not available until
2494 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL
2495 this is instead controlled by the value of
2496 /config/load-environment.
2498 - DataFlash Support:
2499 CONFIG_HAS_DATAFLASH
2501 Defining this option enables DataFlash features and
2502 allows to read/write in Dataflash via the standard
2505 - Serial Flash support
2508 Defining this option enables SPI flash commands
2509 'sf probe/read/write/erase/update'.
2511 Usage requires an initial 'probe' to define the serial
2512 flash parameters, followed by read/write/erase/update
2515 The following defaults may be provided by the platform
2516 to handle the common case when only a single serial
2517 flash is present on the system.
2519 CONFIG_SF_DEFAULT_BUS Bus identifier
2520 CONFIG_SF_DEFAULT_CS Chip-select
2521 CONFIG_SF_DEFAULT_MODE (see include/spi.h)
2522 CONFIG_SF_DEFAULT_SPEED in Hz
2526 Define this option to include a destructive SPI flash
2529 CONFIG_SPI_FLASH_BAR Ban/Extended Addr Reg
2531 Define this option to use the Bank addr/Extended addr
2532 support on SPI flashes which has size > 16Mbytes.
2534 - SystemACE Support:
2537 Adding this option adds support for Xilinx SystemACE
2538 chips attached via some sort of local bus. The address
2539 of the chip must also be defined in the
2540 CONFIG_SYS_SYSTEMACE_BASE macro. For example:
2542 #define CONFIG_SYSTEMACE
2543 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000
2545 When SystemACE support is added, the "ace" device type
2546 becomes available to the fat commands, i.e. fatls.
2548 - TFTP Fixed UDP Port:
2551 If this is defined, the environment variable tftpsrcp
2552 is used to supply the TFTP UDP source port value.
2553 If tftpsrcp isn't defined, the normal pseudo-random port
2554 number generator is used.
2556 Also, the environment variable tftpdstp is used to supply
2557 the TFTP UDP destination port value. If tftpdstp isn't
2558 defined, the normal port 69 is used.
2560 The purpose for tftpsrcp is to allow a TFTP server to
2561 blindly start the TFTP transfer using the pre-configured
2562 target IP address and UDP port. This has the effect of
2563 "punching through" the (Windows XP) firewall, allowing
2564 the remainder of the TFTP transfer to proceed normally.
2565 A better solution is to properly configure the firewall,
2566 but sometimes that is not allowed.
2571 This enables a generic 'hash' command which can produce
2572 hashes / digests from a few algorithms (e.g. SHA1, SHA256).
2576 Enable the hash verify command (hash -v). This adds to code
2579 CONFIG_SHA1 - support SHA1 hashing
2580 CONFIG_SHA256 - support SHA256 hashing
2582 Note: There is also a sha1sum command, which should perhaps
2583 be deprecated in favour of 'hash sha1'.
2588 This enables the RSA algorithm used for FIT image verification
2589 in U-Boot. See doc/uImage/signature for more information.
2591 The signing part is build into mkimage regardless of this
2595 - Show boot progress:
2596 CONFIG_SHOW_BOOT_PROGRESS
2598 Defining this option allows to add some board-
2599 specific code (calling a user-provided function
2600 "show_boot_progress(int)") that enables you to show
2601 the system's boot progress on some display (for
2602 example, some LED's) on your board. At the moment,
2603 the following checkpoints are implemented:
2605 - Detailed boot stage timing
2607 Define this option to get detailed timing of each stage
2608 of the boot process.
2610 CONFIG_BOOTSTAGE_USER_COUNT
2611 This is the number of available user bootstage records.
2612 Each time you call bootstage_mark(BOOTSTAGE_ID_ALLOC, ...)
2613 a new ID will be allocated from this stash. If you exceed
2614 the limit, recording will stop.
2616 CONFIG_BOOTSTAGE_REPORT
2617 Define this to print a report before boot, similar to this:
2619 Timer summary in microseconds:
2622 3,575,678 3,575,678 board_init_f start
2623 3,575,695 17 arch_cpu_init A9
2624 3,575,777 82 arch_cpu_init done
2625 3,659,598 83,821 board_init_r start
2626 3,910,375 250,777 main_loop
2627 29,916,167 26,005,792 bootm_start
2628 30,361,327 445,160 start_kernel
2630 CONFIG_CMD_BOOTSTAGE
2631 Add a 'bootstage' command which supports printing a report
2632 and un/stashing of bootstage data.
2634 CONFIG_BOOTSTAGE_FDT
2635 Stash the bootstage information in the FDT. A root 'bootstage'
2636 node is created with each bootstage id as a child. Each child
2637 has a 'name' property and either 'mark' containing the
2638 mark time in microsecond, or 'accum' containing the
2639 accumulated time for that bootstage id in microseconds.
2644 name = "board_init_f";
2653 Code in the Linux kernel can find this in /proc/devicetree.
2655 Legacy uImage format:
2658 1 common/cmd_bootm.c before attempting to boot an image
2659 -1 common/cmd_bootm.c Image header has bad magic number
2660 2 common/cmd_bootm.c Image header has correct magic number
2661 -2 common/cmd_bootm.c Image header has bad checksum
2662 3 common/cmd_bootm.c Image header has correct checksum
2663 -3 common/cmd_bootm.c Image data has bad checksum
2664 4 common/cmd_bootm.c Image data has correct checksum
2665 -4 common/cmd_bootm.c Image is for unsupported architecture
2666 5 common/cmd_bootm.c Architecture check OK
2667 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
2668 6 common/cmd_bootm.c Image Type check OK
2669 -6 common/cmd_bootm.c gunzip uncompression error
2670 -7 common/cmd_bootm.c Unimplemented compression type
2671 7 common/cmd_bootm.c Uncompression OK
2672 8 common/cmd_bootm.c No uncompress/copy overwrite error
2673 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
2675 9 common/image.c Start initial ramdisk verification
2676 -10 common/image.c Ramdisk header has bad magic number
2677 -11 common/image.c Ramdisk header has bad checksum
2678 10 common/image.c Ramdisk header is OK
2679 -12 common/image.c Ramdisk data has bad checksum
2680 11 common/image.c Ramdisk data has correct checksum
2681 12 common/image.c Ramdisk verification complete, start loading
2682 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
2683 13 common/image.c Start multifile image verification
2684 14 common/image.c No initial ramdisk, no multifile, continue.
2686 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
2688 -30 arch/powerpc/lib/board.c Fatal error, hang the system
2689 -31 post/post.c POST test failed, detected by post_output_backlog()
2690 -32 post/post.c POST test failed, detected by post_run_single()
2692 34 common/cmd_doc.c before loading a Image from a DOC device
2693 -35 common/cmd_doc.c Bad usage of "doc" command
2694 35 common/cmd_doc.c correct usage of "doc" command
2695 -36 common/cmd_doc.c No boot device
2696 36 common/cmd_doc.c correct boot device
2697 -37 common/cmd_doc.c Unknown Chip ID on boot device
2698 37 common/cmd_doc.c correct chip ID found, device available
2699 -38 common/cmd_doc.c Read Error on boot device
2700 38 common/cmd_doc.c reading Image header from DOC device OK
2701 -39 common/cmd_doc.c Image header has bad magic number
2702 39 common/cmd_doc.c Image header has correct magic number
2703 -40 common/cmd_doc.c Error reading Image from DOC device
2704 40 common/cmd_doc.c Image header has correct magic number
2705 41 common/cmd_ide.c before loading a Image from a IDE device
2706 -42 common/cmd_ide.c Bad usage of "ide" command
2707 42 common/cmd_ide.c correct usage of "ide" command
2708 -43 common/cmd_ide.c No boot device
2709 43 common/cmd_ide.c boot device found
2710 -44 common/cmd_ide.c Device not available
2711 44 common/cmd_ide.c Device available
2712 -45 common/cmd_ide.c wrong partition selected
2713 45 common/cmd_ide.c partition selected
2714 -46 common/cmd_ide.c Unknown partition table
2715 46 common/cmd_ide.c valid partition table found
2716 -47 common/cmd_ide.c Invalid partition type
2717 47 common/cmd_ide.c correct partition type
2718 -48 common/cmd_ide.c Error reading Image Header on boot device
2719 48 common/cmd_ide.c reading Image Header from IDE device OK
2720 -49 common/cmd_ide.c Image header has bad magic number
2721 49 common/cmd_ide.c Image header has correct magic number
2722 -50 common/cmd_ide.c Image header has bad checksum
2723 50 common/cmd_ide.c Image header has correct checksum
2724 -51 common/cmd_ide.c Error reading Image from IDE device
2725 51 common/cmd_ide.c reading Image from IDE device OK
2726 52 common/cmd_nand.c before loading a Image from a NAND device
2727 -53 common/cmd_nand.c Bad usage of "nand" command
2728 53 common/cmd_nand.c correct usage of "nand" command
2729 -54 common/cmd_nand.c No boot device
2730 54 common/cmd_nand.c boot device found
2731 -55 common/cmd_nand.c Unknown Chip ID on boot device
2732 55 common/cmd_nand.c correct chip ID found, device available
2733 -56 common/cmd_nand.c Error reading Image Header on boot device
2734 56 common/cmd_nand.c reading Image Header from NAND device OK
2735 -57 common/cmd_nand.c Image header has bad magic number
2736 57 common/cmd_nand.c Image header has correct magic number
2737 -58 common/cmd_nand.c Error reading Image from NAND device
2738 58 common/cmd_nand.c reading Image from NAND device OK
2740 -60 common/env_common.c Environment has a bad CRC, using default
2742 64 net/eth.c starting with Ethernet configuration.
2743 -64 net/eth.c no Ethernet found.
2744 65 net/eth.c Ethernet found.
2746 -80 common/cmd_net.c usage wrong
2747 80 common/cmd_net.c before calling NetLoop()
2748 -81 common/cmd_net.c some error in NetLoop() occurred
2749 81 common/cmd_net.c NetLoop() back without error
2750 -82 common/cmd_net.c size == 0 (File with size 0 loaded)
2751 82 common/cmd_net.c trying automatic boot
2752 83 common/cmd_net.c running "source" command
2753 -83 common/cmd_net.c some error in automatic boot or "source" command
2754 84 common/cmd_net.c end without errors
2759 100 common/cmd_bootm.c Kernel FIT Image has correct format
2760 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
2761 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
2762 -101 common/cmd_bootm.c Can't get configuration for kernel subimage
2763 102 common/cmd_bootm.c Kernel unit name specified
2764 -103 common/cmd_bootm.c Can't get kernel subimage node offset
2765 103 common/cmd_bootm.c Found configuration node
2766 104 common/cmd_bootm.c Got kernel subimage node offset
2767 -104 common/cmd_bootm.c Kernel subimage hash verification failed
2768 105 common/cmd_bootm.c Kernel subimage hash verification OK
2769 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
2770 106 common/cmd_bootm.c Architecture check OK
2771 -106 common/cmd_bootm.c Kernel subimage has wrong type
2772 107 common/cmd_bootm.c Kernel subimage type OK
2773 -107 common/cmd_bootm.c Can't get kernel subimage data/size
2774 108 common/cmd_bootm.c Got kernel subimage data/size
2775 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
2776 -109 common/cmd_bootm.c Can't get kernel subimage type
2777 -110 common/cmd_bootm.c Can't get kernel subimage comp
2778 -111 common/cmd_bootm.c Can't get kernel subimage os
2779 -112 common/cmd_bootm.c Can't get kernel subimage load address
2780 -113 common/cmd_bootm.c Image uncompress/copy overwrite error
2782 120 common/image.c Start initial ramdisk verification
2783 -120 common/image.c Ramdisk FIT image has incorrect format
2784 121 common/image.c Ramdisk FIT image has correct format
2785 122 common/image.c No ramdisk subimage unit name, using configuration
2786 -122 common/image.c Can't get configuration for ramdisk subimage
2787 123 common/image.c Ramdisk unit name specified
2788 -124 common/image.c Can't get ramdisk subimage node offset
2789 125 common/image.c Got ramdisk subimage node offset
2790 -125 common/image.c Ramdisk subimage hash verification failed
2791 126 common/image.c Ramdisk subimage hash verification OK
2792 -126 common/image.c Ramdisk subimage for unsupported architecture
2793 127 common/image.c Architecture check OK
2794 -127 common/image.c Can't get ramdisk subimage data/size
2795 128 common/image.c Got ramdisk subimage data/size
2796 129 common/image.c Can't get ramdisk load address
2797 -129 common/image.c Got ramdisk load address
2799 -130 common/cmd_doc.c Incorrect FIT image format
2800 131 common/cmd_doc.c FIT image format OK
2802 -140 common/cmd_ide.c Incorrect FIT image format
2803 141 common/cmd_ide.c FIT image format OK
2805 -150 common/cmd_nand.c Incorrect FIT image format
2806 151 common/cmd_nand.c FIT image format OK
2808 - FIT image support:
2810 Enable support for the FIT uImage format.
2812 CONFIG_FIT_BEST_MATCH
2813 When no configuration is explicitly selected, default to the
2814 one whose fdt's compatibility field best matches that of
2815 U-Boot itself. A match is considered "best" if it matches the
2816 most specific compatibility entry of U-Boot's fdt's root node.
2817 The order of entries in the configuration's fdt is ignored.
2819 CONFIG_FIT_SIGNATURE
2820 This option enables signature verification of FIT uImages,
2821 using a hash signed and verified using RSA. See
2822 doc/uImage.FIT/signature.txt for more details.
2824 - Standalone program support:
2825 CONFIG_STANDALONE_LOAD_ADDR
2827 This option defines a board specific value for the
2828 address where standalone program gets loaded, thus
2829 overwriting the architecture dependent default
2832 - Frame Buffer Address:
2835 Define CONFIG_FB_ADDR if you want to use specific
2836 address for frame buffer. This is typically the case
2837 when using a graphics controller has separate video
2838 memory. U-Boot will then place the frame buffer at
2839 the given address instead of dynamically reserving it
2840 in system RAM by calling lcd_setmem(), which grabs
2841 the memory for the frame buffer depending on the
2842 configured panel size.
2844 Please see board_init_f function.
2846 - Automatic software updates via TFTP server
2848 CONFIG_UPDATE_TFTP_CNT_MAX
2849 CONFIG_UPDATE_TFTP_MSEC_MAX
2851 These options enable and control the auto-update feature;
2852 for a more detailed description refer to doc/README.update.
2854 - MTD Support (mtdparts command, UBI support)
2857 Adds the MTD device infrastructure from the Linux kernel.
2858 Needed for mtdparts command support.
2860 CONFIG_MTD_PARTITIONS
2862 Adds the MTD partitioning infrastructure from the Linux
2863 kernel. Needed for UBI support.
2868 Adds commands for interacting with MTD partitions formatted
2869 with the UBI flash translation layer
2871 Requires also defining CONFIG_RBTREE
2873 CONFIG_UBI_SILENCE_MSG
2875 Make the verbose messages from UBI stop printing. This leaves
2876 warnings and errors enabled.
2881 Adds commands for interacting with UBI volumes formatted as
2882 UBIFS. UBIFS is read-only in u-boot.
2884 Requires UBI support as well as CONFIG_LZO
2886 CONFIG_UBIFS_SILENCE_MSG
2888 Make the verbose messages from UBIFS stop printing. This leaves
2889 warnings and errors enabled.
2893 Enable building of SPL globally.
2896 LDSCRIPT for linking the SPL binary.
2898 CONFIG_SPL_MAX_FOOTPRINT
2899 Maximum size in memory allocated to the SPL, BSS included.
2900 When defined, the linker checks that the actual memory
2901 used by SPL from _start to __bss_end does not exceed it.
2902 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
2903 must not be both defined at the same time.
2906 Maximum size of the SPL image (text, data, rodata, and
2907 linker lists sections), BSS excluded.
2908 When defined, the linker checks that the actual size does
2911 CONFIG_SPL_TEXT_BASE
2912 TEXT_BASE for linking the SPL binary.
2914 CONFIG_SPL_RELOC_TEXT_BASE
2915 Address to relocate to. If unspecified, this is equal to
2916 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done).
2918 CONFIG_SPL_BSS_START_ADDR
2919 Link address for the BSS within the SPL binary.
2921 CONFIG_SPL_BSS_MAX_SIZE
2922 Maximum size in memory allocated to the SPL BSS.
2923 When defined, the linker checks that the actual memory used
2924 by SPL from __bss_start to __bss_end does not exceed it.
2925 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
2926 must not be both defined at the same time.
2929 Adress of the start of the stack SPL will use
2931 CONFIG_SPL_RELOC_STACK
2932 Adress of the start of the stack SPL will use after
2933 relocation. If unspecified, this is equal to
2936 CONFIG_SYS_SPL_MALLOC_START
2937 Starting address of the malloc pool used in SPL.
2939 CONFIG_SYS_SPL_MALLOC_SIZE
2940 The size of the malloc pool used in SPL.
2942 CONFIG_SPL_FRAMEWORK
2943 Enable the SPL framework under common/. This framework
2944 supports MMC, NAND and YMODEM loading of U-Boot and NAND
2945 NAND loading of the Linux Kernel.
2947 CONFIG_SPL_DISPLAY_PRINT
2948 For ARM, enable an optional function to print more information
2949 about the running system.
2951 CONFIG_SPL_INIT_MINIMAL
2952 Arch init code should be built for a very small image
2954 CONFIG_SPL_LIBCOMMON_SUPPORT
2955 Support for common/libcommon.o in SPL binary
2957 CONFIG_SPL_LIBDISK_SUPPORT
2958 Support for disk/libdisk.o in SPL binary
2960 CONFIG_SPL_I2C_SUPPORT
2961 Support for drivers/i2c/libi2c.o in SPL binary
2963 CONFIG_SPL_GPIO_SUPPORT
2964 Support for drivers/gpio/libgpio.o in SPL binary
2966 CONFIG_SPL_MMC_SUPPORT
2967 Support for drivers/mmc/libmmc.o in SPL binary
2969 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR,
2970 CONFIG_SYS_U_BOOT_MAX_SIZE_SECTORS,
2971 CONFIG_SYS_MMC_SD_FAT_BOOT_PARTITION
2972 Address, size and partition on the MMC to load U-Boot from
2973 when the MMC is being used in raw mode.
2975 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR
2976 Sector to load kernel uImage from when MMC is being
2977 used in raw mode (for Falcon mode)
2979 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR,
2980 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS
2981 Sector and number of sectors to load kernel argument
2982 parameters from when MMC is being used in raw mode
2985 CONFIG_SPL_FAT_SUPPORT
2986 Support for fs/fat/libfat.o in SPL binary
2988 CONFIG_SPL_FAT_LOAD_PAYLOAD_NAME
2989 Filename to read to load U-Boot when reading from FAT
2991 CONFIG_SPL_FAT_LOAD_KERNEL_NAME
2992 Filename to read to load kernel uImage when reading
2993 from FAT (for Falcon mode)
2995 CONFIG_SPL_FAT_LOAD_ARGS_NAME
2996 Filename to read to load kernel argument parameters
2997 when reading from FAT (for Falcon mode)
2999 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND
3000 Set this for NAND SPL on PPC mpc83xx targets, so that
3001 start.S waits for the rest of the SPL to load before
3002 continuing (the hardware starts execution after just
3003 loading the first page rather than the full 4K).
3005 CONFIG_SPL_NAND_BASE
3006 Include nand_base.c in the SPL. Requires
3007 CONFIG_SPL_NAND_DRIVERS.
3009 CONFIG_SPL_NAND_DRIVERS
3010 SPL uses normal NAND drivers, not minimal drivers.
3013 Include standard software ECC in the SPL
3015 CONFIG_SPL_NAND_SIMPLE
3016 Support for NAND boot using simple NAND drivers that
3017 expose the cmd_ctrl() interface.
3019 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
3020 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
3021 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
3022 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE,
3023 CONFIG_SYS_NAND_ECCBYTES
3024 Defines the size and behavior of the NAND that SPL uses
3027 CONFIG_SYS_NAND_U_BOOT_OFFS
3028 Location in NAND to read U-Boot from
3030 CONFIG_SYS_NAND_U_BOOT_DST
3031 Location in memory to load U-Boot to
3033 CONFIG_SYS_NAND_U_BOOT_SIZE
3034 Size of image to load
3036 CONFIG_SYS_NAND_U_BOOT_START
3037 Entry point in loaded image to jump to
3039 CONFIG_SYS_NAND_HW_ECC_OOBFIRST
3040 Define this if you need to first read the OOB and then the
3041 data. This is used for example on davinci plattforms.
3043 CONFIG_SPL_OMAP3_ID_NAND
3044 Support for an OMAP3-specific set of functions to return the
3045 ID and MFR of the first attached NAND chip, if present.
3047 CONFIG_SPL_SERIAL_SUPPORT
3048 Support for drivers/serial/libserial.o in SPL binary
3050 CONFIG_SPL_SPI_FLASH_SUPPORT
3051 Support for drivers/mtd/spi/libspi_flash.o in SPL binary
3053 CONFIG_SPL_SPI_SUPPORT
3054 Support for drivers/spi/libspi.o in SPL binary
3056 CONFIG_SPL_RAM_DEVICE
3057 Support for running image already present in ram, in SPL binary
3059 CONFIG_SPL_LIBGENERIC_SUPPORT
3060 Support for lib/libgeneric.o in SPL binary
3062 CONFIG_SPL_ENV_SUPPORT
3063 Support for the environment operating in SPL binary
3065 CONFIG_SPL_NET_SUPPORT
3066 Support for the net/libnet.o in SPL binary.
3067 It conflicts with SPL env from storage medium specified by
3068 CONFIG_ENV_IS_xxx but CONFIG_ENV_IS_NOWHERE
3071 Image offset to which the SPL should be padded before appending
3072 the SPL payload. By default, this is defined as
3073 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
3074 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
3075 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
3078 Final target image containing SPL and payload. Some SPLs
3079 use an arch-specific makefile fragment instead, for
3080 example if more than one image needs to be produced.
3082 CONFIG_FIT_SPL_PRINT
3083 Printing information about a FIT image adds quite a bit of
3084 code to SPL. So this is normally disabled in SPL. Use this
3085 option to re-enable it. This will affect the output of the
3086 bootm command when booting a FIT image.
3091 [so far only for SMDK2400 boards]
3093 - Modem support enable:
3094 CONFIG_MODEM_SUPPORT
3096 - RTS/CTS Flow control enable:
3099 - Modem debug support:
3100 CONFIG_MODEM_SUPPORT_DEBUG
3102 Enables debugging stuff (char screen[1024], dbg())
3103 for modem support. Useful only with BDI2000.
3105 - Interrupt support (PPC):
3107 There are common interrupt_init() and timer_interrupt()
3108 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
3109 for CPU specific initialization. interrupt_init_cpu()
3110 should set decrementer_count to appropriate value. If
3111 CPU resets decrementer automatically after interrupt
3112 (ppc4xx) it should set decrementer_count to zero.
3113 timer_interrupt() calls timer_interrupt_cpu() for CPU
3114 specific handling. If board has watchdog / status_led
3115 / other_activity_monitor it works automatically from
3116 general timer_interrupt().
3120 In the target system modem support is enabled when a
3121 specific key (key combination) is pressed during
3122 power-on. Otherwise U-Boot will boot normally
3123 (autoboot). The key_pressed() function is called from
3124 board_init(). Currently key_pressed() is a dummy
3125 function, returning 1 and thus enabling modem
3128 If there are no modem init strings in the
3129 environment, U-Boot proceed to autoboot; the
3130 previous output (banner, info printfs) will be
3133 See also: doc/README.Modem
3135 Board initialization settings:
3136 ------------------------------
3138 During Initialization u-boot calls a number of board specific functions
3139 to allow the preparation of board specific prerequisites, e.g. pin setup
3140 before drivers are initialized. To enable these callbacks the
3141 following configuration macros have to be defined. Currently this is
3142 architecture specific, so please check arch/your_architecture/lib/board.c
3143 typically in board_init_f() and board_init_r().
3145 - CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
3146 - CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
3147 - CONFIG_BOARD_LATE_INIT: Call board_late_init()
3148 - CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init()
3150 Configuration Settings:
3151 -----------------------
3153 - CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
3154 undefine this when you're short of memory.
3156 - CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
3157 width of the commands listed in the 'help' command output.
3159 - CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
3160 prompt for user input.
3162 - CONFIG_SYS_CBSIZE: Buffer size for input from the Console
3164 - CONFIG_SYS_PBSIZE: Buffer size for Console output
3166 - CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
3168 - CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
3169 the application (usually a Linux kernel) when it is
3172 - CONFIG_SYS_BAUDRATE_TABLE:
3173 List of legal baudrate settings for this board.
3175 - CONFIG_SYS_CONSOLE_INFO_QUIET
3176 Suppress display of console information at boot.
3178 - CONFIG_SYS_CONSOLE_IS_IN_ENV
3179 If the board specific function
3180 extern int overwrite_console (void);
3181 returns 1, the stdin, stderr and stdout are switched to the
3182 serial port, else the settings in the environment are used.
3184 - CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE
3185 Enable the call to overwrite_console().
3187 - CONFIG_SYS_CONSOLE_ENV_OVERWRITE
3188 Enable overwrite of previous console environment settings.
3190 - CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
3191 Begin and End addresses of the area used by the
3194 - CONFIG_SYS_ALT_MEMTEST:
3195 Enable an alternate, more extensive memory test.
3197 - CONFIG_SYS_MEMTEST_SCRATCH:
3198 Scratch address used by the alternate memory test
3199 You only need to set this if address zero isn't writeable
3201 - CONFIG_SYS_MEM_TOP_HIDE (PPC only):
3202 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
3203 this specified memory area will get subtracted from the top
3204 (end) of RAM and won't get "touched" at all by U-Boot. By
3205 fixing up gd->ram_size the Linux kernel should gets passed
3206 the now "corrected" memory size and won't touch it either.
3207 This should work for arch/ppc and arch/powerpc. Only Linux
3208 board ports in arch/powerpc with bootwrapper support that
3209 recalculate the memory size from the SDRAM controller setup
3210 will have to get fixed in Linux additionally.
3212 This option can be used as a workaround for the 440EPx/GRx
3213 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
3216 WARNING: Please make sure that this value is a multiple of
3217 the Linux page size (normally 4k). If this is not the case,
3218 then the end address of the Linux memory will be located at a
3219 non page size aligned address and this could cause major
3222 - CONFIG_SYS_LOADS_BAUD_CHANGE:
3223 Enable temporary baudrate change while serial download
3225 - CONFIG_SYS_SDRAM_BASE:
3226 Physical start address of SDRAM. _Must_ be 0 here.
3228 - CONFIG_SYS_MBIO_BASE:
3229 Physical start address of Motherboard I/O (if using a
3232 - CONFIG_SYS_FLASH_BASE:
3233 Physical start address of Flash memory.
3235 - CONFIG_SYS_MONITOR_BASE:
3236 Physical start address of boot monitor code (set by
3237 make config files to be same as the text base address
3238 (CONFIG_SYS_TEXT_BASE) used when linking) - same as
3239 CONFIG_SYS_FLASH_BASE when booting from flash.
3241 - CONFIG_SYS_MONITOR_LEN:
3242 Size of memory reserved for monitor code, used to
3243 determine _at_compile_time_ (!) if the environment is
3244 embedded within the U-Boot image, or in a separate
3247 - CONFIG_SYS_MALLOC_LEN:
3248 Size of DRAM reserved for malloc() use.
3250 - CONFIG_SYS_BOOTM_LEN:
3251 Normally compressed uImages are limited to an
3252 uncompressed size of 8 MBytes. If this is not enough,
3253 you can define CONFIG_SYS_BOOTM_LEN in your board config file
3254 to adjust this setting to your needs.
3256 - CONFIG_SYS_BOOTMAPSZ:
3257 Maximum size of memory mapped by the startup code of
3258 the Linux kernel; all data that must be processed by
3259 the Linux kernel (bd_info, boot arguments, FDT blob if
3260 used) must be put below this limit, unless "bootm_low"
3261 enviroment variable is defined and non-zero. In such case
3262 all data for the Linux kernel must be between "bootm_low"
3263 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
3264 variable "bootm_mapsize" will override the value of
3265 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
3266 then the value in "bootm_size" will be used instead.
3268 - CONFIG_SYS_BOOT_RAMDISK_HIGH:
3269 Enable initrd_high functionality. If defined then the
3270 initrd_high feature is enabled and the bootm ramdisk subcommand
3273 - CONFIG_SYS_BOOT_GET_CMDLINE:
3274 Enables allocating and saving kernel cmdline in space between
3275 "bootm_low" and "bootm_low" + BOOTMAPSZ.
3277 - CONFIG_SYS_BOOT_GET_KBD:
3278 Enables allocating and saving a kernel copy of the bd_info in
3279 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
3281 - CONFIG_SYS_MAX_FLASH_BANKS:
3282 Max number of Flash memory banks
3284 - CONFIG_SYS_MAX_FLASH_SECT:
3285 Max number of sectors on a Flash chip
3287 - CONFIG_SYS_FLASH_ERASE_TOUT:
3288 Timeout for Flash erase operations (in ms)
3290 - CONFIG_SYS_FLASH_WRITE_TOUT:
3291 Timeout for Flash write operations (in ms)
3293 - CONFIG_SYS_FLASH_LOCK_TOUT
3294 Timeout for Flash set sector lock bit operation (in ms)
3296 - CONFIG_SYS_FLASH_UNLOCK_TOUT
3297 Timeout for Flash clear lock bits operation (in ms)
3299 - CONFIG_SYS_FLASH_PROTECTION
3300 If defined, hardware flash sectors protection is used
3301 instead of U-Boot software protection.
3303 - CONFIG_SYS_DIRECT_FLASH_TFTP:
3305 Enable TFTP transfers directly to flash memory;
3306 without this option such a download has to be
3307 performed in two steps: (1) download to RAM, and (2)
3308 copy from RAM to flash.
3310 The two-step approach is usually more reliable, since
3311 you can check if the download worked before you erase
3312 the flash, but in some situations (when system RAM is
3313 too limited to allow for a temporary copy of the
3314 downloaded image) this option may be very useful.
3316 - CONFIG_SYS_FLASH_CFI:
3317 Define if the flash driver uses extra elements in the
3318 common flash structure for storing flash geometry.
3320 - CONFIG_FLASH_CFI_DRIVER
3321 This option also enables the building of the cfi_flash driver
3322 in the drivers directory
3324 - CONFIG_FLASH_CFI_MTD
3325 This option enables the building of the cfi_mtd driver
3326 in the drivers directory. The driver exports CFI flash
3329 - CONFIG_SYS_FLASH_USE_BUFFER_WRITE
3330 Use buffered writes to flash.
3332 - CONFIG_FLASH_SPANSION_S29WS_N
3333 s29ws-n MirrorBit flash has non-standard addresses for buffered
3336 - CONFIG_SYS_FLASH_QUIET_TEST
3337 If this option is defined, the common CFI flash doesn't
3338 print it's warning upon not recognized FLASH banks. This
3339 is useful, if some of the configured banks are only
3340 optionally available.
3342 - CONFIG_FLASH_SHOW_PROGRESS
3343 If defined (must be an integer), print out countdown
3344 digits and dots. Recommended value: 45 (9..1) for 80
3345 column displays, 15 (3..1) for 40 column displays.
3347 - CONFIG_FLASH_VERIFY
3348 If defined, the content of the flash (destination) is compared
3349 against the source after the write operation. An error message
3350 will be printed when the contents are not identical.
3351 Please note that this option is useless in nearly all cases,
3352 since such flash programming errors usually are detected earlier
3353 while unprotecting/erasing/programming. Please only enable
3354 this option if you really know what you are doing.
3356 - CONFIG_SYS_RX_ETH_BUFFER:
3357 Defines the number of Ethernet receive buffers. On some
3358 Ethernet controllers it is recommended to set this value
3359 to 8 or even higher (EEPRO100 or 405 EMAC), since all
3360 buffers can be full shortly after enabling the interface
3361 on high Ethernet traffic.
3362 Defaults to 4 if not defined.
3364 - CONFIG_ENV_MAX_ENTRIES
3366 Maximum number of entries in the hash table that is used
3367 internally to store the environment settings. The default
3368 setting is supposed to be generous and should work in most
3369 cases. This setting can be used to tune behaviour; see
3370 lib/hashtable.c for details.
3372 - CONFIG_ENV_FLAGS_LIST_DEFAULT
3373 - CONFIG_ENV_FLAGS_LIST_STATIC
3374 Enable validation of the values given to enviroment variables when
3375 calling env set. Variables can be restricted to only decimal,
3376 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined,
3377 the variables can also be restricted to IP address or MAC address.
3379 The format of the list is:
3380 type_attribute = [s|d|x|b|i|m]
3381 access_atribute = [a|r|o|c]
3382 attributes = type_attribute[access_atribute]
3383 entry = variable_name[:attributes]
3386 The type attributes are:
3387 s - String (default)
3390 b - Boolean ([1yYtT|0nNfF])
3394 The access attributes are:
3400 - CONFIG_ENV_FLAGS_LIST_DEFAULT
3401 Define this to a list (string) to define the ".flags"
3402 envirnoment variable in the default or embedded environment.
3404 - CONFIG_ENV_FLAGS_LIST_STATIC
3405 Define this to a list (string) to define validation that
3406 should be done if an entry is not found in the ".flags"
3407 environment variable. To override a setting in the static
3408 list, simply add an entry for the same variable name to the
3411 - CONFIG_ENV_ACCESS_IGNORE_FORCE
3412 If defined, don't allow the -f switch to env set override variable
3415 - CONFIG_SYS_GENERIC_BOARD
3416 This selects the architecture-generic board system instead of the
3417 architecture-specific board files. It is intended to move boards
3418 to this new framework over time. Defining this will disable the
3419 arch/foo/lib/board.c file and use common/board_f.c and
3420 common/board_r.c instead. To use this option your architecture
3421 must support it (i.e. must define __HAVE_ARCH_GENERIC_BOARD in
3422 its config.mk file). If you find problems enabling this option on
3423 your board please report the problem and send patches!
3425 - CONFIG_SYS_SYM_OFFSETS
3426 This is set by architectures that use offsets for link symbols
3427 instead of absolute values. So bss_start is obtained using an
3428 offset _bss_start_ofs from CONFIG_SYS_TEXT_BASE, rather than
3429 directly. You should not need to touch this setting.
3431 - CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC (OMAP only)
3432 This is set by OMAP boards for the max time that reset should
3433 be asserted. See doc/README.omap-reset-time for details on how
3434 the value can be calulated on a given board.
3436 The following definitions that deal with the placement and management
3437 of environment data (variable area); in general, we support the
3438 following configurations:
3440 - CONFIG_BUILD_ENVCRC:
3442 Builds up envcrc with the target environment so that external utils
3443 may easily extract it and embed it in final U-Boot images.
3445 - CONFIG_ENV_IS_IN_FLASH:
3447 Define this if the environment is in flash memory.
3449 a) The environment occupies one whole flash sector, which is
3450 "embedded" in the text segment with the U-Boot code. This
3451 happens usually with "bottom boot sector" or "top boot
3452 sector" type flash chips, which have several smaller
3453 sectors at the start or the end. For instance, such a
3454 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
3455 such a case you would place the environment in one of the
3456 4 kB sectors - with U-Boot code before and after it. With
3457 "top boot sector" type flash chips, you would put the
3458 environment in one of the last sectors, leaving a gap
3459 between U-Boot and the environment.
3461 - CONFIG_ENV_OFFSET:
3463 Offset of environment data (variable area) to the
3464 beginning of flash memory; for instance, with bottom boot
3465 type flash chips the second sector can be used: the offset
3466 for this sector is given here.
3468 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE.
3472 This is just another way to specify the start address of
3473 the flash sector containing the environment (instead of
3476 - CONFIG_ENV_SECT_SIZE:
3478 Size of the sector containing the environment.
3481 b) Sometimes flash chips have few, equal sized, BIG sectors.
3482 In such a case you don't want to spend a whole sector for
3487 If you use this in combination with CONFIG_ENV_IS_IN_FLASH
3488 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part
3489 of this flash sector for the environment. This saves
3490 memory for the RAM copy of the environment.
3492 It may also save flash memory if you decide to use this
3493 when your environment is "embedded" within U-Boot code,
3494 since then the remainder of the flash sector could be used
3495 for U-Boot code. It should be pointed out that this is
3496 STRONGLY DISCOURAGED from a robustness point of view:
3497 updating the environment in flash makes it always
3498 necessary to erase the WHOLE sector. If something goes
3499 wrong before the contents has been restored from a copy in
3500 RAM, your target system will be dead.
3502 - CONFIG_ENV_ADDR_REDUND
3503 CONFIG_ENV_SIZE_REDUND
3505 These settings describe a second storage area used to hold
3506 a redundant copy of the environment data, so that there is
3507 a valid backup copy in case there is a power failure during
3508 a "saveenv" operation.
3510 BE CAREFUL! Any changes to the flash layout, and some changes to the
3511 source code will make it necessary to adapt <board>/u-boot.lds*
3515 - CONFIG_ENV_IS_IN_NVRAM:
3517 Define this if you have some non-volatile memory device
3518 (NVRAM, battery buffered SRAM) which you want to use for the
3524 These two #defines are used to determine the memory area you
3525 want to use for environment. It is assumed that this memory
3526 can just be read and written to, without any special
3529 BE CAREFUL! The first access to the environment happens quite early
3530 in U-Boot initalization (when we try to get the setting of for the
3531 console baudrate). You *MUST* have mapped your NVRAM area then, or
3534 Please note that even with NVRAM we still use a copy of the
3535 environment in RAM: we could work on NVRAM directly, but we want to
3536 keep settings there always unmodified except somebody uses "saveenv"
3537 to save the current settings.
3540 - CONFIG_ENV_IS_IN_EEPROM:
3542 Use this if you have an EEPROM or similar serial access
3543 device and a driver for it.
3545 - CONFIG_ENV_OFFSET:
3548 These two #defines specify the offset and size of the
3549 environment area within the total memory of your EEPROM.
3551 - CONFIG_SYS_I2C_EEPROM_ADDR:
3552 If defined, specified the chip address of the EEPROM device.
3553 The default address is zero.
3555 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS:
3556 If defined, the number of bits used to address bytes in a
3557 single page in the EEPROM device. A 64 byte page, for example
3558 would require six bits.
3560 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS:
3561 If defined, the number of milliseconds to delay between
3562 page writes. The default is zero milliseconds.
3564 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN:
3565 The length in bytes of the EEPROM memory array address. Note
3566 that this is NOT the chip address length!
3568 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW:
3569 EEPROM chips that implement "address overflow" are ones
3570 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
3571 address and the extra bits end up in the "chip address" bit
3572 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
3575 Note that we consider the length of the address field to
3576 still be one byte because the extra address bits are hidden
3577 in the chip address.
3579 - CONFIG_SYS_EEPROM_SIZE:
3580 The size in bytes of the EEPROM device.
3582 - CONFIG_ENV_EEPROM_IS_ON_I2C
3583 define this, if you have I2C and SPI activated, and your
3584 EEPROM, which holds the environment, is on the I2C bus.
3586 - CONFIG_I2C_ENV_EEPROM_BUS
3587 if you have an Environment on an EEPROM reached over
3588 I2C muxes, you can define here, how to reach this
3589 EEPROM. For example:
3591 #define CONFIG_I2C_ENV_EEPROM_BUS "pca9547:70:d\0"
3593 EEPROM which holds the environment, is reached over
3594 a pca9547 i2c mux with address 0x70, channel 3.
3596 - CONFIG_ENV_IS_IN_DATAFLASH:
3598 Define this if you have a DataFlash memory device which you
3599 want to use for the environment.
3601 - CONFIG_ENV_OFFSET:
3605 These three #defines specify the offset and size of the
3606 environment area within the total memory of your DataFlash placed
3607 at the specified address.
3609 - CONFIG_ENV_IS_IN_REMOTE:
3611 Define this if you have a remote memory space which you
3612 want to use for the local device's environment.
3617 These two #defines specify the address and size of the
3618 environment area within the remote memory space. The
3619 local device can get the environment from remote memory
3620 space by SRIO or PCIE links.
3622 BE CAREFUL! For some special cases, the local device can not use
3623 "saveenv" command. For example, the local device will get the
3624 environment stored in a remote NOR flash by SRIO or PCIE link,
3625 but it can not erase, write this NOR flash by SRIO or PCIE interface.
3627 - CONFIG_ENV_IS_IN_NAND:
3629 Define this if you have a NAND device which you want to use
3630 for the environment.
3632 - CONFIG_ENV_OFFSET:
3635 These two #defines specify the offset and size of the environment
3636 area within the first NAND device. CONFIG_ENV_OFFSET must be
3637 aligned to an erase block boundary.
3639 - CONFIG_ENV_OFFSET_REDUND (optional):
3641 This setting describes a second storage area of CONFIG_ENV_SIZE
3642 size used to hold a redundant copy of the environment data, so
3643 that there is a valid backup copy in case there is a power failure
3644 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be
3645 aligned to an erase block boundary.
3647 - CONFIG_ENV_RANGE (optional):
3649 Specifies the length of the region in which the environment
3650 can be written. This should be a multiple of the NAND device's
3651 block size. Specifying a range with more erase blocks than
3652 are needed to hold CONFIG_ENV_SIZE allows bad blocks within
3653 the range to be avoided.
3655 - CONFIG_ENV_OFFSET_OOB (optional):
3657 Enables support for dynamically retrieving the offset of the
3658 environment from block zero's out-of-band data. The
3659 "nand env.oob" command can be used to record this offset.
3660 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when
3661 using CONFIG_ENV_OFFSET_OOB.
3663 - CONFIG_NAND_ENV_DST
3665 Defines address in RAM to which the nand_spl code should copy the
3666 environment. If redundant environment is used, it will be copied to
3667 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
3669 - CONFIG_ENV_IS_IN_UBI:
3671 Define this if you have an UBI volume that you want to use for the
3672 environment. This has the benefit of wear-leveling the environment
3673 accesses, which is important on NAND.
3675 - CONFIG_ENV_UBI_PART:
3677 Define this to a string that is the mtd partition containing the UBI.
3679 - CONFIG_ENV_UBI_VOLUME:
3681 Define this to the name of the volume that you want to store the
3684 - CONFIG_ENV_UBI_VOLUME_REDUND:
3686 Define this to the name of another volume to store a second copy of
3687 the environment in. This will enable redundant environments in UBI.
3688 It is assumed that both volumes are in the same MTD partition.
3690 - CONFIG_UBI_SILENCE_MSG
3691 - CONFIG_UBIFS_SILENCE_MSG
3693 You will probably want to define these to avoid a really noisy system
3694 when storing the env in UBI.
3696 - CONFIG_ENV_IS_IN_MMC:
3698 Define this if you have an MMC device which you want to use for the
3701 - CONFIG_SYS_MMC_ENV_DEV:
3703 Specifies which MMC device the environment is stored in.
3705 - CONFIG_SYS_MMC_ENV_PART (optional):
3707 Specifies which MMC partition the environment is stored in. If not
3708 set, defaults to partition 0, the user area. Common values might be
3709 1 (first MMC boot partition), 2 (second MMC boot partition).
3711 - CONFIG_ENV_OFFSET:
3714 These two #defines specify the offset and size of the environment
3715 area within the specified MMC device.
3717 If offset is positive (the usual case), it is treated as relative to
3718 the start of the MMC partition. If offset is negative, it is treated
3719 as relative to the end of the MMC partition. This can be useful if
3720 your board may be fitted with different MMC devices, which have
3721 different sizes for the MMC partitions, and you always want the
3722 environment placed at the very end of the partition, to leave the
3723 maximum possible space before it, to store other data.
3725 These two values are in units of bytes, but must be aligned to an
3726 MMC sector boundary.
3728 - CONFIG_ENV_OFFSET_REDUND (optional):
3730 Specifies a second storage area, of CONFIG_ENV_SIZE size, used to
3731 hold a redundant copy of the environment data. This provides a
3732 valid backup copy in case the other copy is corrupted, e.g. due
3733 to a power failure during a "saveenv" operation.
3735 This value may also be positive or negative; this is handled in the
3736 same way as CONFIG_ENV_OFFSET.
3738 This value is also in units of bytes, but must also be aligned to
3739 an MMC sector boundary.
3741 - CONFIG_ENV_SIZE_REDUND (optional):
3743 This value need not be set, even when CONFIG_ENV_OFFSET_REDUND is
3744 set. If this value is set, it must be set to the same value as
3747 - CONFIG_SYS_SPI_INIT_OFFSET
3749 Defines offset to the initial SPI buffer area in DPRAM. The
3750 area is used at an early stage (ROM part) if the environment
3751 is configured to reside in the SPI EEPROM: We need a 520 byte
3752 scratch DPRAM area. It is used between the two initialization
3753 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
3754 to be a good choice since it makes it far enough from the
3755 start of the data area as well as from the stack pointer.
3757 Please note that the environment is read-only until the monitor
3758 has been relocated to RAM and a RAM copy of the environment has been
3759 created; also, when using EEPROM you will have to use getenv_f()
3760 until then to read environment variables.
3762 The environment is protected by a CRC32 checksum. Before the monitor
3763 is relocated into RAM, as a result of a bad CRC you will be working
3764 with the compiled-in default environment - *silently*!!! [This is
3765 necessary, because the first environment variable we need is the
3766 "baudrate" setting for the console - if we have a bad CRC, we don't
3767 have any device yet where we could complain.]
3769 Note: once the monitor has been relocated, then it will complain if
3770 the default environment is used; a new CRC is computed as soon as you
3771 use the "saveenv" command to store a valid environment.
3773 - CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
3774 Echo the inverted Ethernet link state to the fault LED.
3776 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
3777 also needs to be defined.
3779 - CONFIG_SYS_FAULT_MII_ADDR:
3780 MII address of the PHY to check for the Ethernet link state.
3782 - CONFIG_NS16550_MIN_FUNCTIONS:
3783 Define this if you desire to only have use of the NS16550_init
3784 and NS16550_putc functions for the serial driver located at
3785 drivers/serial/ns16550.c. This option is useful for saving
3786 space for already greatly restricted images, including but not
3787 limited to NAND_SPL configurations.
3789 - CONFIG_DISPLAY_BOARDINFO
3790 Display information about the board that U-Boot is running on
3791 when U-Boot starts up. The board function checkboard() is called
3794 - CONFIG_DISPLAY_BOARDINFO_LATE
3795 Similar to the previous option, but display this information
3796 later, once stdio is running and output goes to the LCD, if
3799 Low Level (hardware related) configuration options:
3800 ---------------------------------------------------
3802 - CONFIG_SYS_CACHELINE_SIZE:
3803 Cache Line Size of the CPU.
3805 - CONFIG_SYS_DEFAULT_IMMR:
3806 Default address of the IMMR after system reset.
3808 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
3809 and RPXsuper) to be able to adjust the position of
3810 the IMMR register after a reset.
3812 - CONFIG_SYS_CCSRBAR_DEFAULT:
3813 Default (power-on reset) physical address of CCSR on Freescale
3816 - CONFIG_SYS_CCSRBAR:
3817 Virtual address of CCSR. On a 32-bit build, this is typically
3818 the same value as CONFIG_SYS_CCSRBAR_DEFAULT.
3820 CONFIG_SYS_DEFAULT_IMMR must also be set to this value,
3821 for cross-platform code that uses that macro instead.
3823 - CONFIG_SYS_CCSRBAR_PHYS:
3824 Physical address of CCSR. CCSR can be relocated to a new
3825 physical address, if desired. In this case, this macro should
3826 be set to that address. Otherwise, it should be set to the
3827 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR
3828 is typically relocated on 36-bit builds. It is recommended
3829 that this macro be defined via the _HIGH and _LOW macros:
3831 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH
3832 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW)
3834 - CONFIG_SYS_CCSRBAR_PHYS_HIGH:
3835 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically
3836 either 0 (32-bit build) or 0xF (36-bit build). This macro is
3837 used in assembly code, so it must not contain typecasts or
3838 integer size suffixes (e.g. "ULL").
3840 - CONFIG_SYS_CCSRBAR_PHYS_LOW:
3841 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is
3842 used in assembly code, so it must not contain typecasts or
3843 integer size suffixes (e.g. "ULL").
3845 - CONFIG_SYS_CCSR_DO_NOT_RELOCATE:
3846 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be
3847 forced to a value that ensures that CCSR is not relocated.
3849 - Floppy Disk Support:
3850 CONFIG_SYS_FDC_DRIVE_NUMBER
3852 the default drive number (default value 0)
3854 CONFIG_SYS_ISA_IO_STRIDE
3856 defines the spacing between FDC chipset registers
3859 CONFIG_SYS_ISA_IO_OFFSET
3861 defines the offset of register from address. It
3862 depends on which part of the data bus is connected to
3863 the FDC chipset. (default value 0)
3865 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
3866 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
3869 if CONFIG_SYS_FDC_HW_INIT is defined, then the function
3870 fdc_hw_init() is called at the beginning of the FDC
3871 setup. fdc_hw_init() must be provided by the board
3872 source code. It is used to make hardware dependant
3876 Most IDE controllers were designed to be connected with PCI
3877 interface. Only few of them were designed for AHB interface.
3878 When software is doing ATA command and data transfer to
3879 IDE devices through IDE-AHB controller, some additional
3880 registers accessing to these kind of IDE-AHB controller
3883 - CONFIG_SYS_IMMR: Physical address of the Internal Memory.
3884 DO NOT CHANGE unless you know exactly what you're
3885 doing! (11-4) [MPC8xx/82xx systems only]
3887 - CONFIG_SYS_INIT_RAM_ADDR:
3889 Start address of memory area that can be used for
3890 initial data and stack; please note that this must be
3891 writable memory that is working WITHOUT special
3892 initialization, i. e. you CANNOT use normal RAM which
3893 will become available only after programming the
3894 memory controller and running certain initialization
3897 U-Boot uses the following memory types:
3898 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
3899 - MPC824X: data cache
3900 - PPC4xx: data cache
3902 - CONFIG_SYS_GBL_DATA_OFFSET:
3904 Offset of the initial data structure in the memory
3905 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
3906 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
3907 data is located at the end of the available space
3908 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
3909 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just
3910 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
3911 CONFIG_SYS_GBL_DATA_OFFSET) downward.
3914 On the MPC824X (or other systems that use the data
3915 cache for initial memory) the address chosen for
3916 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
3917 point to an otherwise UNUSED address space between
3918 the top of RAM and the start of the PCI space.
3920 - CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6)
3922 - CONFIG_SYS_SYPCR: System Protection Control (11-9)
3924 - CONFIG_SYS_TBSCR: Time Base Status and Control (11-26)
3926 - CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31)
3928 - CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
3930 - CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
3932 - CONFIG_SYS_OR_TIMING_SDRAM:
3935 - CONFIG_SYS_MAMR_PTA:
3936 periodic timer for refresh
3938 - CONFIG_SYS_DER: Debug Event Register (37-47)
3940 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
3941 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
3942 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
3943 CONFIG_SYS_BR1_PRELIM:
3944 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
3946 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
3947 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
3948 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
3949 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
3951 - CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K,
3952 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL:
3953 Machine Mode Register and Memory Periodic Timer
3954 Prescaler definitions (SDRAM timing)
3956 - CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]:
3957 enable I2C microcode relocation patch (MPC8xx);
3958 define relocation offset in DPRAM [DSP2]
3960 - CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]:
3961 enable SMC microcode relocation patch (MPC8xx);
3962 define relocation offset in DPRAM [SMC1]
3964 - CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]:
3965 enable SPI microcode relocation patch (MPC8xx);
3966 define relocation offset in DPRAM [SCC4]
3968 - CONFIG_SYS_USE_OSCCLK:
3969 Use OSCM clock mode on MBX8xx board. Be careful,
3970 wrong setting might damage your board. Read
3971 doc/README.MBX before setting this variable!
3973 - CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
3974 Offset of the bootmode word in DPRAM used by post
3975 (Power On Self Tests). This definition overrides
3976 #define'd default value in commproc.h resp.
3979 - CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB,
3980 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL,
3981 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS,
3982 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB,
3983 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
3984 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL,
3985 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE,
3986 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only)
3987 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set.
3989 - CONFIG_PCI_DISABLE_PCIE:
3990 Disable PCI-Express on systems where it is supported but not
3993 - CONFIG_PCI_ENUM_ONLY
3994 Only scan through and get the devices on the busses.
3995 Don't do any setup work, presumably because someone or
3996 something has already done it, and we don't need to do it
3997 a second time. Useful for platforms that are pre-booted
3998 by coreboot or similar.
4000 - CONFIG_PCI_INDIRECT_BRIDGE:
4001 Enable support for indirect PCI bridges.
4004 Chip has SRIO or not
4007 Board has SRIO 1 port available
4010 Board has SRIO 2 port available
4012 - CONFIG_SRIO_PCIE_BOOT_MASTER
4013 Board can support master function for Boot from SRIO and PCIE
4015 - CONFIG_SYS_SRIOn_MEM_VIRT:
4016 Virtual Address of SRIO port 'n' memory region
4018 - CONFIG_SYS_SRIOn_MEM_PHYS:
4019 Physical Address of SRIO port 'n' memory region
4021 - CONFIG_SYS_SRIOn_MEM_SIZE:
4022 Size of SRIO port 'n' memory region
4024 - CONFIG_SYS_NAND_BUSWIDTH_16BIT
4025 Defined to tell the NAND controller that the NAND chip is using
4027 Not all NAND drivers use this symbol.
4028 Example of drivers that use it:
4029 - drivers/mtd/nand/ndfc.c
4030 - drivers/mtd/nand/mxc_nand.c
4032 - CONFIG_SYS_NDFC_EBC0_CFG
4033 Sets the EBC0_CFG register for the NDFC. If not defined
4034 a default value will be used.
4037 Get DDR timing information from an I2C EEPROM. Common
4038 with pluggable memory modules such as SODIMMs
4041 I2C address of the SPD EEPROM
4043 - CONFIG_SYS_SPD_BUS_NUM
4044 If SPD EEPROM is on an I2C bus other than the first
4045 one, specify here. Note that the value must resolve
4046 to something your driver can deal with.
4048 - CONFIG_SYS_DDR_RAW_TIMING
4049 Get DDR timing information from other than SPD. Common with
4050 soldered DDR chips onboard without SPD. DDR raw timing
4051 parameters are extracted from datasheet and hard-coded into
4052 header files or board specific files.
4054 - CONFIG_FSL_DDR_INTERACTIVE
4055 Enable interactive DDR debugging. See doc/README.fsl-ddr.
4057 - CONFIG_SYS_83XX_DDR_USES_CS0
4058 Only for 83xx systems. If specified, then DDR should
4059 be configured using CS0 and CS1 instead of CS2 and CS3.
4061 - CONFIG_ETHER_ON_FEC[12]
4062 Define to enable FEC[12] on a 8xx series processor.
4064 - CONFIG_FEC[12]_PHY
4065 Define to the hardcoded PHY address which corresponds
4066 to the given FEC; i. e.
4067 #define CONFIG_FEC1_PHY 4
4068 means that the PHY with address 4 is connected to FEC1
4070 When set to -1, means to probe for first available.
4072 - CONFIG_FEC[12]_PHY_NORXERR
4073 The PHY does not have a RXERR line (RMII only).
4074 (so program the FEC to ignore it).
4077 Enable RMII mode for all FECs.
4078 Note that this is a global option, we can't
4079 have one FEC in standard MII mode and another in RMII mode.
4081 - CONFIG_CRC32_VERIFY
4082 Add a verify option to the crc32 command.
4085 => crc32 -v <address> <count> <crc32>
4087 Where address/count indicate a memory area
4088 and crc32 is the correct crc32 which the
4092 Add the "loopw" memory command. This only takes effect if
4093 the memory commands are activated globally (CONFIG_CMD_MEM).
4096 Add the "mdc" and "mwc" memory commands. These are cyclic
4101 This command will print 4 bytes (10,11,12,13) each 500 ms.
4103 => mwc.l 100 12345678 10
4104 This command will write 12345678 to address 100 all 10 ms.
4106 This only takes effect if the memory commands are activated
4107 globally (CONFIG_CMD_MEM).
4109 - CONFIG_SKIP_LOWLEVEL_INIT
4110 [ARM, NDS32, MIPS only] If this variable is defined, then certain
4111 low level initializations (like setting up the memory
4112 controller) are omitted and/or U-Boot does not
4113 relocate itself into RAM.
4115 Normally this variable MUST NOT be defined. The only
4116 exception is when U-Boot is loaded (to RAM) by some
4117 other boot loader or by a debugger which performs
4118 these initializations itself.
4121 Modifies the behaviour of start.S when compiling a loader
4122 that is executed before the actual U-Boot. E.g. when
4123 compiling a NAND SPL.
4125 - CONFIG_SYS_MPC85XX_NO_RESETVEC
4126 Only for 85xx systems. If this variable is specified, the section
4127 .resetvec is not kept and the section .bootpg is placed in the
4128 previous 4k of the .text section.
4130 - CONFIG_ARCH_MAP_SYSMEM
4131 Generally U-Boot (and in particular the md command) uses
4132 effective address. It is therefore not necessary to regard
4133 U-Boot address as virtual addresses that need to be translated
4134 to physical addresses. However, sandbox requires this, since
4135 it maintains its own little RAM buffer which contains all
4136 addressable memory. This option causes some memory accesses
4137 to be mapped through map_sysmem() / unmap_sysmem().
4139 - CONFIG_USE_ARCH_MEMCPY
4140 CONFIG_USE_ARCH_MEMSET
4141 If these options are used a optimized version of memcpy/memset will
4142 be used if available. These functions may be faster under some
4143 conditions but may increase the binary size.
4145 - CONFIG_X86_RESET_VECTOR
4146 If defined, the x86 reset vector code is included. This is not
4147 needed when U-Boot is running from Coreboot.
4150 Defines the MPU clock speed (in MHz).
4152 NOTE : currently only supported on AM335x platforms.
4154 Freescale QE/FMAN Firmware Support:
4155 -----------------------------------
4157 The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
4158 loading of "firmware", which is encoded in the QE firmware binary format.
4159 This firmware often needs to be loaded during U-Boot booting, so macros
4160 are used to identify the storage device (NOR flash, SPI, etc) and the address
4163 - CONFIG_SYS_QE_FMAN_FW_ADDR
4164 The address in the storage device where the firmware is located. The
4165 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
4168 - CONFIG_SYS_QE_FMAN_FW_LENGTH
4169 The maximum possible size of the firmware. The firmware binary format
4170 has a field that specifies the actual size of the firmware, but it
4171 might not be possible to read any part of the firmware unless some
4172 local storage is allocated to hold the entire firmware first.
4174 - CONFIG_SYS_QE_FMAN_FW_IN_NOR
4175 Specifies that QE/FMAN firmware is located in NOR flash, mapped as
4176 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the
4177 virtual address in NOR flash.
4179 - CONFIG_SYS_QE_FMAN_FW_IN_NAND
4180 Specifies that QE/FMAN firmware is located in NAND flash.
4181 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.
4183 - CONFIG_SYS_QE_FMAN_FW_IN_MMC
4184 Specifies that QE/FMAN firmware is located on the primary SD/MMC
4185 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
4187 - CONFIG_SYS_QE_FMAN_FW_IN_SPIFLASH
4188 Specifies that QE/FMAN firmware is located on the primary SPI
4189 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
4191 - CONFIG_SYS_QE_FMAN_FW_IN_REMOTE
4192 Specifies that QE/FMAN firmware is located in the remote (master)
4193 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which
4194 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound
4195 window->master inbound window->master LAW->the ucode address in
4196 master's memory space.
4198 Building the Software:
4199 ======================
4201 Building U-Boot has been tested in several native build environments
4202 and in many different cross environments. Of course we cannot support
4203 all possibly existing versions of cross development tools in all
4204 (potentially obsolete) versions. In case of tool chain problems we
4205 recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
4206 which is extensively used to build and test U-Boot.
4208 If you are not using a native environment, it is assumed that you
4209 have GNU cross compiling tools available in your path. In this case,
4210 you must set the environment variable CROSS_COMPILE in your shell.
4211 Note that no changes to the Makefile or any other source files are
4212 necessary. For example using the ELDK on a 4xx CPU, please enter:
4214 $ CROSS_COMPILE=ppc_4xx-
4215 $ export CROSS_COMPILE
4217 Note: If you wish to generate Windows versions of the utilities in
4218 the tools directory you can use the MinGW toolchain
4219 (http://www.mingw.org). Set your HOST tools to the MinGW
4220 toolchain and execute 'make tools'. For example:
4222 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
4224 Binaries such as tools/mkimage.exe will be created which can
4225 be executed on computers running Windows.
4227 U-Boot is intended to be simple to build. After installing the
4228 sources you must configure U-Boot for one specific board type. This
4233 where "NAME_config" is the name of one of the existing configu-
4234 rations; see boards.cfg for supported names.
4236 Note: for some board special configuration names may exist; check if
4237 additional information is available from the board vendor; for
4238 instance, the TQM823L systems are available without (standard)
4239 or with LCD support. You can select such additional "features"
4240 when choosing the configuration, i. e.
4243 - will configure for a plain TQM823L, i. e. no LCD support
4245 make TQM823L_LCD_config
4246 - will configure for a TQM823L with U-Boot console on LCD
4251 Finally, type "make all", and you should get some working U-Boot
4252 images ready for download to / installation on your system:
4254 - "u-boot.bin" is a raw binary image
4255 - "u-boot" is an image in ELF binary format
4256 - "u-boot.srec" is in Motorola S-Record format
4258 By default the build is performed locally and the objects are saved
4259 in the source directory. One of the two methods can be used to change
4260 this behavior and build U-Boot to some external directory:
4262 1. Add O= to the make command line invocations:
4264 make O=/tmp/build distclean
4265 make O=/tmp/build NAME_config
4266 make O=/tmp/build all
4268 2. Set environment variable BUILD_DIR to point to the desired location:
4270 export BUILD_DIR=/tmp/build
4275 Note that the command line "O=" setting overrides the BUILD_DIR environment
4279 Please be aware that the Makefiles assume you are using GNU make, so
4280 for instance on NetBSD you might need to use "gmake" instead of
4284 If the system board that you have is not listed, then you will need
4285 to port U-Boot to your hardware platform. To do this, follow these
4288 1. Add a new configuration option for your board to the toplevel
4289 "boards.cfg" file, using the existing entries as examples.
4290 Follow the instructions there to keep the boards in order.
4291 2. Create a new directory to hold your board specific code. Add any
4292 files you need. In your board directory, you will need at least
4293 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
4294 3. Create a new configuration file "include/configs/<board>.h" for
4296 3. If you're porting U-Boot to a new CPU, then also create a new
4297 directory to hold your CPU specific code. Add any files you need.
4298 4. Run "make <board>_config" with your new name.
4299 5. Type "make", and you should get a working "u-boot.srec" file
4300 to be installed on your target system.
4301 6. Debug and solve any problems that might arise.
4302 [Of course, this last step is much harder than it sounds.]
4305 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
4306 ==============================================================
4308 If you have modified U-Boot sources (for instance added a new board
4309 or support for new devices, a new CPU, etc.) you are expected to
4310 provide feedback to the other developers. The feedback normally takes
4311 the form of a "patch", i. e. a context diff against a certain (latest
4312 official or latest in the git repository) version of U-Boot sources.
4314 But before you submit such a patch, please verify that your modifi-
4315 cation did not break existing code. At least make sure that *ALL* of
4316 the supported boards compile WITHOUT ANY compiler warnings. To do so,
4317 just run the "MAKEALL" script, which will configure and build U-Boot
4318 for ALL supported system. Be warned, this will take a while. You can
4319 select which (cross) compiler to use by passing a `CROSS_COMPILE'
4320 environment variable to the script, i. e. to use the ELDK cross tools
4323 CROSS_COMPILE=ppc_8xx- MAKEALL
4325 or to build on a native PowerPC system you can type
4327 CROSS_COMPILE=' ' MAKEALL
4329 When using the MAKEALL script, the default behaviour is to build
4330 U-Boot in the source directory. This location can be changed by
4331 setting the BUILD_DIR environment variable. Also, for each target
4332 built, the MAKEALL script saves two log files (<target>.ERR and
4333 <target>.MAKEALL) in the <source dir>/LOG directory. This default
4334 location can be changed by setting the MAKEALL_LOGDIR environment
4335 variable. For example:
4337 export BUILD_DIR=/tmp/build
4338 export MAKEALL_LOGDIR=/tmp/log
4339 CROSS_COMPILE=ppc_8xx- MAKEALL
4341 With the above settings build objects are saved in the /tmp/build,
4342 log files are saved in the /tmp/log and the source tree remains clean
4343 during the whole build process.
4346 See also "U-Boot Porting Guide" below.
4349 Monitor Commands - Overview:
4350 ============================
4352 go - start application at address 'addr'
4353 run - run commands in an environment variable
4354 bootm - boot application image from memory
4355 bootp - boot image via network using BootP/TFTP protocol
4356 bootz - boot zImage from memory
4357 tftpboot- boot image via network using TFTP protocol
4358 and env variables "ipaddr" and "serverip"
4359 (and eventually "gatewayip")
4360 tftpput - upload a file via network using TFTP protocol
4361 rarpboot- boot image via network using RARP/TFTP protocol
4362 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
4363 loads - load S-Record file over serial line
4364 loadb - load binary file over serial line (kermit mode)
4366 mm - memory modify (auto-incrementing)
4367 nm - memory modify (constant address)
4368 mw - memory write (fill)
4370 cmp - memory compare
4371 crc32 - checksum calculation
4372 i2c - I2C sub-system
4373 sspi - SPI utility commands
4374 base - print or set address offset
4375 printenv- print environment variables
4376 setenv - set environment variables
4377 saveenv - save environment variables to persistent storage
4378 protect - enable or disable FLASH write protection
4379 erase - erase FLASH memory
4380 flinfo - print FLASH memory information
4381 nand - NAND memory operations (see doc/README.nand)
4382 bdinfo - print Board Info structure
4383 iminfo - print header information for application image
4384 coninfo - print console devices and informations
4385 ide - IDE sub-system
4386 loop - infinite loop on address range
4387 loopw - infinite write loop on address range
4388 mtest - simple RAM test
4389 icache - enable or disable instruction cache
4390 dcache - enable or disable data cache
4391 reset - Perform RESET of the CPU
4392 echo - echo args to console
4393 version - print monitor version
4394 help - print online help
4395 ? - alias for 'help'
4398 Monitor Commands - Detailed Description:
4399 ========================================
4403 For now: just type "help <command>".
4406 Environment Variables:
4407 ======================
4409 U-Boot supports user configuration using Environment Variables which
4410 can be made persistent by saving to Flash memory.
4412 Environment Variables are set using "setenv", printed using
4413 "printenv", and saved to Flash using "saveenv". Using "setenv"
4414 without a value can be used to delete a variable from the
4415 environment. As long as you don't save the environment you are
4416 working with an in-memory copy. In case the Flash area containing the
4417 environment is erased by accident, a default environment is provided.
4419 Some configuration options can be set using Environment Variables.
4421 List of environment variables (most likely not complete):
4423 baudrate - see CONFIG_BAUDRATE
4425 bootdelay - see CONFIG_BOOTDELAY
4427 bootcmd - see CONFIG_BOOTCOMMAND
4429 bootargs - Boot arguments when booting an RTOS image
4431 bootfile - Name of the image to load with TFTP
4433 bootm_low - Memory range available for image processing in the bootm
4434 command can be restricted. This variable is given as
4435 a hexadecimal number and defines lowest address allowed
4436 for use by the bootm command. See also "bootm_size"
4437 environment variable. Address defined by "bootm_low" is
4438 also the base of the initial memory mapping for the Linux
4439 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
4442 bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
4443 This variable is given as a hexadecimal number and it
4444 defines the size of the memory region starting at base
4445 address bootm_low that is accessible by the Linux kernel
4446 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used
4447 as the default value if it is defined, and bootm_size is
4450 bootm_size - Memory range available for image processing in the bootm
4451 command can be restricted. This variable is given as
4452 a hexadecimal number and defines the size of the region
4453 allowed for use by the bootm command. See also "bootm_low"
4454 environment variable.
4456 updatefile - Location of the software update file on a TFTP server, used
4457 by the automatic software update feature. Please refer to
4458 documentation in doc/README.update for more details.
4460 autoload - if set to "no" (any string beginning with 'n'),
4461 "bootp" will just load perform a lookup of the
4462 configuration from the BOOTP server, but not try to
4463 load any image using TFTP
4465 autostart - if set to "yes", an image loaded using the "bootp",
4466 "rarpboot", "tftpboot" or "diskboot" commands will
4467 be automatically started (by internally calling
4470 If set to "no", a standalone image passed to the
4471 "bootm" command will be copied to the load address
4472 (and eventually uncompressed), but NOT be started.
4473 This can be used to load and uncompress arbitrary
4476 fdt_high - if set this restricts the maximum address that the
4477 flattened device tree will be copied into upon boot.
4478 For example, if you have a system with 1 GB memory
4479 at physical address 0x10000000, while Linux kernel
4480 only recognizes the first 704 MB as low memory, you
4481 may need to set fdt_high as 0x3C000000 to have the
4482 device tree blob be copied to the maximum address
4483 of the 704 MB low memory, so that Linux kernel can
4484 access it during the boot procedure.
4486 If this is set to the special value 0xFFFFFFFF then
4487 the fdt will not be copied at all on boot. For this
4488 to work it must reside in writable memory, have
4489 sufficient padding on the end of it for u-boot to
4490 add the information it needs into it, and the memory
4491 must be accessible by the kernel.
4493 fdtcontroladdr- if set this is the address of the control flattened
4494 device tree used by U-Boot when CONFIG_OF_CONTROL is
4497 i2cfast - (PPC405GP|PPC405EP only)
4498 if set to 'y' configures Linux I2C driver for fast
4499 mode (400kHZ). This environment variable is used in
4500 initialization code. So, for changes to be effective
4501 it must be saved and board must be reset.
4503 initrd_high - restrict positioning of initrd images:
4504 If this variable is not set, initrd images will be
4505 copied to the highest possible address in RAM; this
4506 is usually what you want since it allows for
4507 maximum initrd size. If for some reason you want to
4508 make sure that the initrd image is loaded below the
4509 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
4510 variable to a value of "no" or "off" or "0".
4511 Alternatively, you can set it to a maximum upper
4512 address to use (U-Boot will still check that it
4513 does not overwrite the U-Boot stack and data).
4515 For instance, when you have a system with 16 MB
4516 RAM, and want to reserve 4 MB from use by Linux,
4517 you can do this by adding "mem=12M" to the value of
4518 the "bootargs" variable. However, now you must make
4519 sure that the initrd image is placed in the first
4520 12 MB as well - this can be done with
4522 setenv initrd_high 00c00000
4524 If you set initrd_high to 0xFFFFFFFF, this is an
4525 indication to U-Boot that all addresses are legal
4526 for the Linux kernel, including addresses in flash
4527 memory. In this case U-Boot will NOT COPY the
4528 ramdisk at all. This may be useful to reduce the
4529 boot time on your system, but requires that this
4530 feature is supported by your Linux kernel.
4532 ipaddr - IP address; needed for tftpboot command
4534 loadaddr - Default load address for commands like "bootp",
4535 "rarpboot", "tftpboot", "loadb" or "diskboot"
4537 loads_echo - see CONFIG_LOADS_ECHO
4539 serverip - TFTP server IP address; needed for tftpboot command
4541 bootretry - see CONFIG_BOOT_RETRY_TIME
4543 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
4545 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
4547 ethprime - controls which interface is used first.
4549 ethact - controls which interface is currently active.
4550 For example you can do the following
4552 => setenv ethact FEC
4553 => ping 192.168.0.1 # traffic sent on FEC
4554 => setenv ethact SCC
4555 => ping 10.0.0.1 # traffic sent on SCC
4557 ethrotate - When set to "no" U-Boot does not go through all
4558 available network interfaces.
4559 It just stays at the currently selected interface.
4561 netretry - When set to "no" each network operation will
4562 either succeed or fail without retrying.
4563 When set to "once" the network operation will
4564 fail when all the available network interfaces
4565 are tried once without success.
4566 Useful on scripts which control the retry operation
4569 npe_ucode - set load address for the NPE microcode
4571 tftpsrcport - If this is set, the value is used for TFTP's
4574 tftpdstport - If this is set, the value is used for TFTP's UDP
4575 destination port instead of the Well Know Port 69.
4577 tftpblocksize - Block size to use for TFTP transfers; if not set,
4578 we use the TFTP server's default block size
4580 tftptimeout - Retransmission timeout for TFTP packets (in milli-
4581 seconds, minimum value is 1000 = 1 second). Defines
4582 when a packet is considered to be lost so it has to
4583 be retransmitted. The default is 5000 = 5 seconds.
4584 Lowering this value may make downloads succeed
4585 faster in networks with high packet loss rates or
4586 with unreliable TFTP servers.
4588 vlan - When set to a value < 4095 the traffic over
4589 Ethernet is encapsulated/received over 802.1q
4592 The following image location variables contain the location of images
4593 used in booting. The "Image" column gives the role of the image and is
4594 not an environment variable name. The other columns are environment
4595 variable names. "File Name" gives the name of the file on a TFTP
4596 server, "RAM Address" gives the location in RAM the image will be
4597 loaded to, and "Flash Location" gives the image's address in NOR
4598 flash or offset in NAND flash.
4600 *Note* - these variables don't have to be defined for all boards, some
4601 boards currenlty use other variables for these purposes, and some
4602 boards use these variables for other purposes.
4604 Image File Name RAM Address Flash Location
4605 ----- --------- ----------- --------------
4606 u-boot u-boot u-boot_addr_r u-boot_addr
4607 Linux kernel bootfile kernel_addr_r kernel_addr
4608 device tree blob fdtfile fdt_addr_r fdt_addr
4609 ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr
4611 The following environment variables may be used and automatically
4612 updated by the network boot commands ("bootp" and "rarpboot"),
4613 depending the information provided by your boot server:
4615 bootfile - see above
4616 dnsip - IP address of your Domain Name Server
4617 dnsip2 - IP address of your secondary Domain Name Server
4618 gatewayip - IP address of the Gateway (Router) to use
4619 hostname - Target hostname
4621 netmask - Subnet Mask
4622 rootpath - Pathname of the root filesystem on the NFS server
4623 serverip - see above
4626 There are two special Environment Variables:
4628 serial# - contains hardware identification information such
4629 as type string and/or serial number
4630 ethaddr - Ethernet address
4632 These variables can be set only once (usually during manufacturing of
4633 the board). U-Boot refuses to delete or overwrite these variables
4634 once they have been set once.
4637 Further special Environment Variables:
4639 ver - Contains the U-Boot version string as printed
4640 with the "version" command. This variable is
4641 readonly (see CONFIG_VERSION_VARIABLE).
4644 Please note that changes to some configuration parameters may take
4645 only effect after the next boot (yes, that's just like Windoze :-).
4648 Callback functions for environment variables:
4649 ---------------------------------------------
4651 For some environment variables, the behavior of u-boot needs to change
4652 when their values are changed. This functionailty allows functions to
4653 be associated with arbitrary variables. On creation, overwrite, or
4654 deletion, the callback will provide the opportunity for some side
4655 effect to happen or for the change to be rejected.
4657 The callbacks are named and associated with a function using the
4658 U_BOOT_ENV_CALLBACK macro in your board or driver code.
4660 These callbacks are associated with variables in one of two ways. The
4661 static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC
4662 in the board configuration to a string that defines a list of
4663 associations. The list must be in the following format:
4665 entry = variable_name[:callback_name]
4668 If the callback name is not specified, then the callback is deleted.
4669 Spaces are also allowed anywhere in the list.
4671 Callbacks can also be associated by defining the ".callbacks" variable
4672 with the same list format above. Any association in ".callbacks" will
4673 override any association in the static list. You can define
4674 CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the
4675 ".callbacks" envirnoment variable in the default or embedded environment.
4678 Command Line Parsing:
4679 =====================
4681 There are two different command line parsers available with U-Boot:
4682 the old "simple" one, and the much more powerful "hush" shell:
4684 Old, simple command line parser:
4685 --------------------------------
4687 - supports environment variables (through setenv / saveenv commands)
4688 - several commands on one line, separated by ';'
4689 - variable substitution using "... ${name} ..." syntax
4690 - special characters ('$', ';') can be escaped by prefixing with '\',
4692 setenv bootcmd bootm \${address}
4693 - You can also escape text by enclosing in single apostrophes, for example:
4694 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
4699 - similar to Bourne shell, with control structures like
4700 if...then...else...fi, for...do...done; while...do...done,
4701 until...do...done, ...
4702 - supports environment ("global") variables (through setenv / saveenv
4703 commands) and local shell variables (through standard shell syntax
4704 "name=value"); only environment variables can be used with "run"
4710 (1) If a command line (or an environment variable executed by a "run"
4711 command) contains several commands separated by semicolon, and
4712 one of these commands fails, then the remaining commands will be
4715 (2) If you execute several variables with one call to run (i. e.
4716 calling run with a list of variables as arguments), any failing
4717 command will cause "run" to terminate, i. e. the remaining
4718 variables are not executed.
4720 Note for Redundant Ethernet Interfaces:
4721 =======================================
4723 Some boards come with redundant Ethernet interfaces; U-Boot supports
4724 such configurations and is capable of automatic selection of a
4725 "working" interface when needed. MAC assignment works as follows:
4727 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
4728 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
4729 "eth1addr" (=>eth1), "eth2addr", ...
4731 If the network interface stores some valid MAC address (for instance
4732 in SROM), this is used as default address if there is NO correspon-
4733 ding setting in the environment; if the corresponding environment
4734 variable is set, this overrides the settings in the card; that means:
4736 o If the SROM has a valid MAC address, and there is no address in the
4737 environment, the SROM's address is used.
4739 o If there is no valid address in the SROM, and a definition in the
4740 environment exists, then the value from the environment variable is
4743 o If both the SROM and the environment contain a MAC address, and
4744 both addresses are the same, this MAC address is used.
4746 o If both the SROM and the environment contain a MAC address, and the
4747 addresses differ, the value from the environment is used and a
4750 o If neither SROM nor the environment contain a MAC address, an error
4753 If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
4754 will be programmed into hardware as part of the initialization process. This
4755 may be skipped by setting the appropriate 'ethmacskip' environment variable.
4756 The naming convention is as follows:
4757 "ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
4762 U-Boot is capable of booting (and performing other auxiliary operations on)
4763 images in two formats:
4765 New uImage format (FIT)
4766 -----------------------
4768 Flexible and powerful format based on Flattened Image Tree -- FIT (similar
4769 to Flattened Device Tree). It allows the use of images with multiple
4770 components (several kernels, ramdisks, etc.), with contents protected by
4771 SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
4777 Old image format is based on binary files which can be basically anything,
4778 preceded by a special header; see the definitions in include/image.h for
4779 details; basically, the header defines the following image properties:
4781 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
4782 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
4783 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
4784 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
4786 * Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86,
4787 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
4788 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC).
4789 * Compression Type (uncompressed, gzip, bzip2)
4795 The header is marked by a special Magic Number, and both the header
4796 and the data portions of the image are secured against corruption by
4803 Although U-Boot should support any OS or standalone application
4804 easily, the main focus has always been on Linux during the design of
4807 U-Boot includes many features that so far have been part of some
4808 special "boot loader" code within the Linux kernel. Also, any
4809 "initrd" images to be used are no longer part of one big Linux image;
4810 instead, kernel and "initrd" are separate images. This implementation
4811 serves several purposes:
4813 - the same features can be used for other OS or standalone
4814 applications (for instance: using compressed images to reduce the
4815 Flash memory footprint)
4817 - it becomes much easier to port new Linux kernel versions because
4818 lots of low-level, hardware dependent stuff are done by U-Boot
4820 - the same Linux kernel image can now be used with different "initrd"
4821 images; of course this also means that different kernel images can
4822 be run with the same "initrd". This makes testing easier (you don't
4823 have to build a new "zImage.initrd" Linux image when you just
4824 change a file in your "initrd"). Also, a field-upgrade of the
4825 software is easier now.
4831 Porting Linux to U-Boot based systems:
4832 ---------------------------------------
4834 U-Boot cannot save you from doing all the necessary modifications to
4835 configure the Linux device drivers for use with your target hardware
4836 (no, we don't intend to provide a full virtual machine interface to
4839 But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
4841 Just make sure your machine specific header file (for instance
4842 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
4843 Information structure as we define in include/asm-<arch>/u-boot.h,
4844 and make sure that your definition of IMAP_ADDR uses the same value
4845 as your U-Boot configuration in CONFIG_SYS_IMMR.
4848 Configuring the Linux kernel:
4849 -----------------------------
4851 No specific requirements for U-Boot. Make sure you have some root
4852 device (initial ramdisk, NFS) for your target system.
4855 Building a Linux Image:
4856 -----------------------
4858 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
4859 not used. If you use recent kernel source, a new build target
4860 "uImage" will exist which automatically builds an image usable by
4861 U-Boot. Most older kernels also have support for a "pImage" target,
4862 which was introduced for our predecessor project PPCBoot and uses a
4863 100% compatible format.
4872 The "uImage" build target uses a special tool (in 'tools/mkimage') to
4873 encapsulate a compressed Linux kernel image with header information,
4874 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
4876 * build a standard "vmlinux" kernel image (in ELF binary format):
4878 * convert the kernel into a raw binary image:
4880 ${CROSS_COMPILE}-objcopy -O binary \
4881 -R .note -R .comment \
4882 -S vmlinux linux.bin
4884 * compress the binary image:
4888 * package compressed binary image for U-Boot:
4890 mkimage -A ppc -O linux -T kernel -C gzip \
4891 -a 0 -e 0 -n "Linux Kernel Image" \
4892 -d linux.bin.gz uImage
4895 The "mkimage" tool can also be used to create ramdisk images for use
4896 with U-Boot, either separated from the Linux kernel image, or
4897 combined into one file. "mkimage" encapsulates the images with a 64
4898 byte header containing information about target architecture,
4899 operating system, image type, compression method, entry points, time
4900 stamp, CRC32 checksums, etc.
4902 "mkimage" can be called in two ways: to verify existing images and
4903 print the header information, or to build new images.
4905 In the first form (with "-l" option) mkimage lists the information
4906 contained in the header of an existing U-Boot image; this includes
4907 checksum verification:
4909 tools/mkimage -l image
4910 -l ==> list image header information
4912 The second form (with "-d" option) is used to build a U-Boot image
4913 from a "data file" which is used as image payload:
4915 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
4916 -n name -d data_file image
4917 -A ==> set architecture to 'arch'
4918 -O ==> set operating system to 'os'
4919 -T ==> set image type to 'type'
4920 -C ==> set compression type 'comp'
4921 -a ==> set load address to 'addr' (hex)
4922 -e ==> set entry point to 'ep' (hex)
4923 -n ==> set image name to 'name'
4924 -d ==> use image data from 'datafile'
4926 Right now, all Linux kernels for PowerPC systems use the same load
4927 address (0x00000000), but the entry point address depends on the
4930 - 2.2.x kernels have the entry point at 0x0000000C,
4931 - 2.3.x and later kernels have the entry point at 0x00000000.
4933 So a typical call to build a U-Boot image would read:
4935 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
4936 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
4937 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
4938 > examples/uImage.TQM850L
4939 Image Name: 2.4.4 kernel for TQM850L
4940 Created: Wed Jul 19 02:34:59 2000
4941 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4942 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
4943 Load Address: 0x00000000
4944 Entry Point: 0x00000000
4946 To verify the contents of the image (or check for corruption):
4948 -> tools/mkimage -l examples/uImage.TQM850L
4949 Image Name: 2.4.4 kernel for TQM850L
4950 Created: Wed Jul 19 02:34:59 2000
4951 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4952 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
4953 Load Address: 0x00000000
4954 Entry Point: 0x00000000
4956 NOTE: for embedded systems where boot time is critical you can trade
4957 speed for memory and install an UNCOMPRESSED image instead: this
4958 needs more space in Flash, but boots much faster since it does not
4959 need to be uncompressed:
4961 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
4962 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
4963 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
4964 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
4965 > examples/uImage.TQM850L-uncompressed
4966 Image Name: 2.4.4 kernel for TQM850L
4967 Created: Wed Jul 19 02:34:59 2000
4968 Image Type: PowerPC Linux Kernel Image (uncompressed)
4969 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
4970 Load Address: 0x00000000
4971 Entry Point: 0x00000000
4974 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
4975 when your kernel is intended to use an initial ramdisk:
4977 -> tools/mkimage -n 'Simple Ramdisk Image' \
4978 > -A ppc -O linux -T ramdisk -C gzip \
4979 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
4980 Image Name: Simple Ramdisk Image
4981 Created: Wed Jan 12 14:01:50 2000
4982 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
4983 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
4984 Load Address: 0x00000000
4985 Entry Point: 0x00000000
4988 Installing a Linux Image:
4989 -------------------------
4991 To downloading a U-Boot image over the serial (console) interface,
4992 you must convert the image to S-Record format:
4994 objcopy -I binary -O srec examples/image examples/image.srec
4996 The 'objcopy' does not understand the information in the U-Boot
4997 image header, so the resulting S-Record file will be relative to
4998 address 0x00000000. To load it to a given address, you need to
4999 specify the target address as 'offset' parameter with the 'loads'
5002 Example: install the image to address 0x40100000 (which on the
5003 TQM8xxL is in the first Flash bank):
5005 => erase 40100000 401FFFFF
5011 ## Ready for S-Record download ...
5012 ~>examples/image.srec
5013 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
5015 15989 15990 15991 15992
5016 [file transfer complete]
5018 ## Start Addr = 0x00000000
5021 You can check the success of the download using the 'iminfo' command;
5022 this includes a checksum verification so you can be sure no data
5023 corruption happened:
5027 ## Checking Image at 40100000 ...
5028 Image Name: 2.2.13 for initrd on TQM850L
5029 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5030 Data Size: 335725 Bytes = 327 kB = 0 MB
5031 Load Address: 00000000
5032 Entry Point: 0000000c
5033 Verifying Checksum ... OK
5039 The "bootm" command is used to boot an application that is stored in
5040 memory (RAM or Flash). In case of a Linux kernel image, the contents
5041 of the "bootargs" environment variable is passed to the kernel as
5042 parameters. You can check and modify this variable using the
5043 "printenv" and "setenv" commands:
5046 => printenv bootargs
5047 bootargs=root=/dev/ram
5049 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5051 => printenv bootargs
5052 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5055 ## Booting Linux kernel at 40020000 ...
5056 Image Name: 2.2.13 for NFS on TQM850L
5057 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5058 Data Size: 381681 Bytes = 372 kB = 0 MB
5059 Load Address: 00000000
5060 Entry Point: 0000000c
5061 Verifying Checksum ... OK
5062 Uncompressing Kernel Image ... OK
5063 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
5064 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5065 time_init: decrementer frequency = 187500000/60
5066 Calibrating delay loop... 49.77 BogoMIPS
5067 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
5070 If you want to boot a Linux kernel with initial RAM disk, you pass
5071 the memory addresses of both the kernel and the initrd image (PPBCOOT
5072 format!) to the "bootm" command:
5074 => imi 40100000 40200000
5076 ## Checking Image at 40100000 ...
5077 Image Name: 2.2.13 for initrd on TQM850L
5078 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5079 Data Size: 335725 Bytes = 327 kB = 0 MB
5080 Load Address: 00000000
5081 Entry Point: 0000000c
5082 Verifying Checksum ... OK
5084 ## Checking Image at 40200000 ...
5085 Image Name: Simple Ramdisk Image
5086 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5087 Data Size: 566530 Bytes = 553 kB = 0 MB
5088 Load Address: 00000000
5089 Entry Point: 00000000
5090 Verifying Checksum ... OK
5092 => bootm 40100000 40200000
5093 ## Booting Linux kernel at 40100000 ...
5094 Image Name: 2.2.13 for initrd on TQM850L
5095 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5096 Data Size: 335725 Bytes = 327 kB = 0 MB
5097 Load Address: 00000000
5098 Entry Point: 0000000c
5099 Verifying Checksum ... OK
5100 Uncompressing Kernel Image ... OK
5101 ## Loading RAMDisk Image at 40200000 ...
5102 Image Name: Simple Ramdisk Image
5103 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5104 Data Size: 566530 Bytes = 553 kB = 0 MB
5105 Load Address: 00000000
5106 Entry Point: 00000000
5107 Verifying Checksum ... OK
5108 Loading Ramdisk ... OK
5109 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
5110 Boot arguments: root=/dev/ram
5111 time_init: decrementer frequency = 187500000/60
5112 Calibrating delay loop... 49.77 BogoMIPS
5114 RAMDISK: Compressed image found at block 0
5115 VFS: Mounted root (ext2 filesystem).
5119 Boot Linux and pass a flat device tree:
5122 First, U-Boot must be compiled with the appropriate defines. See the section
5123 titled "Linux Kernel Interface" above for a more in depth explanation. The
5124 following is an example of how to start a kernel and pass an updated
5130 oft=oftrees/mpc8540ads.dtb
5131 => tftp $oftaddr $oft
5132 Speed: 1000, full duplex
5134 TFTP from server 192.168.1.1; our IP address is 192.168.1.101
5135 Filename 'oftrees/mpc8540ads.dtb'.
5136 Load address: 0x300000
5139 Bytes transferred = 4106 (100a hex)
5140 => tftp $loadaddr $bootfile
5141 Speed: 1000, full duplex
5143 TFTP from server 192.168.1.1; our IP address is 192.168.1.2
5145 Load address: 0x200000
5146 Loading:############
5148 Bytes transferred = 1029407 (fb51f hex)
5153 => bootm $loadaddr - $oftaddr
5154 ## Booting image at 00200000 ...
5155 Image Name: Linux-2.6.17-dirty
5156 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5157 Data Size: 1029343 Bytes = 1005.2 kB
5158 Load Address: 00000000
5159 Entry Point: 00000000
5160 Verifying Checksum ... OK
5161 Uncompressing Kernel Image ... OK
5162 Booting using flat device tree at 0x300000
5163 Using MPC85xx ADS machine description
5164 Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
5168 More About U-Boot Image Types:
5169 ------------------------------
5171 U-Boot supports the following image types:
5173 "Standalone Programs" are directly runnable in the environment
5174 provided by U-Boot; it is expected that (if they behave
5175 well) you can continue to work in U-Boot after return from
5176 the Standalone Program.
5177 "OS Kernel Images" are usually images of some Embedded OS which
5178 will take over control completely. Usually these programs
5179 will install their own set of exception handlers, device
5180 drivers, set up the MMU, etc. - this means, that you cannot
5181 expect to re-enter U-Boot except by resetting the CPU.
5182 "RAMDisk Images" are more or less just data blocks, and their
5183 parameters (address, size) are passed to an OS kernel that is
5185 "Multi-File Images" contain several images, typically an OS
5186 (Linux) kernel image and one or more data images like
5187 RAMDisks. This construct is useful for instance when you want
5188 to boot over the network using BOOTP etc., where the boot
5189 server provides just a single image file, but you want to get
5190 for instance an OS kernel and a RAMDisk image.
5192 "Multi-File Images" start with a list of image sizes, each
5193 image size (in bytes) specified by an "uint32_t" in network
5194 byte order. This list is terminated by an "(uint32_t)0".
5195 Immediately after the terminating 0 follow the images, one by
5196 one, all aligned on "uint32_t" boundaries (size rounded up to
5197 a multiple of 4 bytes).
5199 "Firmware Images" are binary images containing firmware (like
5200 U-Boot or FPGA images) which usually will be programmed to
5203 "Script files" are command sequences that will be executed by
5204 U-Boot's command interpreter; this feature is especially
5205 useful when you configure U-Boot to use a real shell (hush)
5206 as command interpreter.
5208 Booting the Linux zImage:
5209 -------------------------
5211 On some platforms, it's possible to boot Linux zImage. This is done
5212 using the "bootz" command. The syntax of "bootz" command is the same
5213 as the syntax of "bootm" command.
5215 Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply
5216 kernel with raw initrd images. The syntax is slightly different, the
5217 address of the initrd must be augmented by it's size, in the following
5218 format: "<initrd addres>:<initrd size>".
5224 One of the features of U-Boot is that you can dynamically load and
5225 run "standalone" applications, which can use some resources of
5226 U-Boot like console I/O functions or interrupt services.
5228 Two simple examples are included with the sources:
5233 'examples/hello_world.c' contains a small "Hello World" Demo
5234 application; it is automatically compiled when you build U-Boot.
5235 It's configured to run at address 0x00040004, so you can play with it
5239 ## Ready for S-Record download ...
5240 ~>examples/hello_world.srec
5241 1 2 3 4 5 6 7 8 9 10 11 ...
5242 [file transfer complete]
5244 ## Start Addr = 0x00040004
5246 => go 40004 Hello World! This is a test.
5247 ## Starting application at 0x00040004 ...
5258 Hit any key to exit ...
5260 ## Application terminated, rc = 0x0
5262 Another example, which demonstrates how to register a CPM interrupt
5263 handler with the U-Boot code, can be found in 'examples/timer.c'.
5264 Here, a CPM timer is set up to generate an interrupt every second.
5265 The interrupt service routine is trivial, just printing a '.'
5266 character, but this is just a demo program. The application can be
5267 controlled by the following keys:
5269 ? - print current values og the CPM Timer registers
5270 b - enable interrupts and start timer
5271 e - stop timer and disable interrupts
5272 q - quit application
5275 ## Ready for S-Record download ...
5276 ~>examples/timer.srec
5277 1 2 3 4 5 6 7 8 9 10 11 ...
5278 [file transfer complete]
5280 ## Start Addr = 0x00040004
5283 ## Starting application at 0x00040004 ...
5286 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
5289 [q, b, e, ?] Set interval 1000000 us
5292 [q, b, e, ?] ........
5293 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
5296 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
5299 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
5302 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
5304 [q, b, e, ?] ...Stopping timer
5306 [q, b, e, ?] ## Application terminated, rc = 0x0
5312 Over time, many people have reported problems when trying to use the
5313 "minicom" terminal emulation program for serial download. I (wd)
5314 consider minicom to be broken, and recommend not to use it. Under
5315 Unix, I recommend to use C-Kermit for general purpose use (and
5316 especially for kermit binary protocol download ("loadb" command), and
5317 use "cu" for S-Record download ("loads" command). See
5318 http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3.
5319 for help with kermit.
5322 Nevertheless, if you absolutely want to use it try adding this
5323 configuration to your "File transfer protocols" section:
5325 Name Program Name U/D FullScr IO-Red. Multi
5326 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
5327 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
5333 Starting at version 0.9.2, U-Boot supports NetBSD both as host
5334 (build U-Boot) and target system (boots NetBSD/mpc8xx).
5336 Building requires a cross environment; it is known to work on
5337 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
5338 need gmake since the Makefiles are not compatible with BSD make).
5339 Note that the cross-powerpc package does not install include files;
5340 attempting to build U-Boot will fail because <machine/ansi.h> is
5341 missing. This file has to be installed and patched manually:
5343 # cd /usr/pkg/cross/powerpc-netbsd/include
5345 # ln -s powerpc machine
5346 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
5347 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
5349 Native builds *don't* work due to incompatibilities between native
5350 and U-Boot include files.
5352 Booting assumes that (the first part of) the image booted is a
5353 stage-2 loader which in turn loads and then invokes the kernel
5354 proper. Loader sources will eventually appear in the NetBSD source
5355 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
5356 meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
5359 Implementation Internals:
5360 =========================
5362 The following is not intended to be a complete description of every
5363 implementation detail. However, it should help to understand the
5364 inner workings of U-Boot and make it easier to port it to custom
5368 Initial Stack, Global Data:
5369 ---------------------------
5371 The implementation of U-Boot is complicated by the fact that U-Boot
5372 starts running out of ROM (flash memory), usually without access to
5373 system RAM (because the memory controller is not initialized yet).
5374 This means that we don't have writable Data or BSS segments, and BSS
5375 is not initialized as zero. To be able to get a C environment working
5376 at all, we have to allocate at least a minimal stack. Implementation
5377 options for this are defined and restricted by the CPU used: Some CPU
5378 models provide on-chip memory (like the IMMR area on MPC8xx and
5379 MPC826x processors), on others (parts of) the data cache can be
5380 locked as (mis-) used as memory, etc.
5382 Chris Hallinan posted a good summary of these issues to the
5383 U-Boot mailing list:
5385 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
5386 From: "Chris Hallinan" <clh@net1plus.com>
5387 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
5390 Correct me if I'm wrong, folks, but the way I understand it
5391 is this: Using DCACHE as initial RAM for Stack, etc, does not
5392 require any physical RAM backing up the cache. The cleverness
5393 is that the cache is being used as a temporary supply of
5394 necessary storage before the SDRAM controller is setup. It's
5395 beyond the scope of this list to explain the details, but you
5396 can see how this works by studying the cache architecture and
5397 operation in the architecture and processor-specific manuals.
5399 OCM is On Chip Memory, which I believe the 405GP has 4K. It
5400 is another option for the system designer to use as an
5401 initial stack/RAM area prior to SDRAM being available. Either
5402 option should work for you. Using CS 4 should be fine if your
5403 board designers haven't used it for something that would
5404 cause you grief during the initial boot! It is frequently not
5407 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
5408 with your processor/board/system design. The default value
5409 you will find in any recent u-boot distribution in
5410 walnut.h should work for you. I'd set it to a value larger
5411 than your SDRAM module. If you have a 64MB SDRAM module, set
5412 it above 400_0000. Just make sure your board has no resources
5413 that are supposed to respond to that address! That code in
5414 start.S has been around a while and should work as is when
5415 you get the config right.
5420 It is essential to remember this, since it has some impact on the C
5421 code for the initialization procedures:
5423 * Initialized global data (data segment) is read-only. Do not attempt
5426 * Do not use any uninitialized global data (or implicitely initialized
5427 as zero data - BSS segment) at all - this is undefined, initiali-
5428 zation is performed later (when relocating to RAM).
5430 * Stack space is very limited. Avoid big data buffers or things like
5433 Having only the stack as writable memory limits means we cannot use
5434 normal global data to share information beween the code. But it
5435 turned out that the implementation of U-Boot can be greatly
5436 simplified by making a global data structure (gd_t) available to all
5437 functions. We could pass a pointer to this data as argument to _all_
5438 functions, but this would bloat the code. Instead we use a feature of
5439 the GCC compiler (Global Register Variables) to share the data: we
5440 place a pointer (gd) to the global data into a register which we
5441 reserve for this purpose.
5443 When choosing a register for such a purpose we are restricted by the
5444 relevant (E)ABI specifications for the current architecture, and by
5445 GCC's implementation.
5447 For PowerPC, the following registers have specific use:
5449 R2: reserved for system use
5450 R3-R4: parameter passing and return values
5451 R5-R10: parameter passing
5452 R13: small data area pointer
5456 (U-Boot also uses R12 as internal GOT pointer. r12
5457 is a volatile register so r12 needs to be reset when
5458 going back and forth between asm and C)
5460 ==> U-Boot will use R2 to hold a pointer to the global data
5462 Note: on PPC, we could use a static initializer (since the
5463 address of the global data structure is known at compile time),
5464 but it turned out that reserving a register results in somewhat
5465 smaller code - although the code savings are not that big (on
5466 average for all boards 752 bytes for the whole U-Boot image,
5467 624 text + 127 data).
5469 On Blackfin, the normal C ABI (except for P3) is followed as documented here:
5470 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface
5472 ==> U-Boot will use P3 to hold a pointer to the global data
5474 On ARM, the following registers are used:
5476 R0: function argument word/integer result
5477 R1-R3: function argument word
5479 R10: stack limit (used only if stack checking if enabled)
5480 R11: argument (frame) pointer
5481 R12: temporary workspace
5484 R15: program counter
5486 ==> U-Boot will use R8 to hold a pointer to the global data
5488 On Nios II, the ABI is documented here:
5489 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
5491 ==> U-Boot will use gp to hold a pointer to the global data
5493 Note: on Nios II, we give "-G0" option to gcc and don't use gp
5494 to access small data sections, so gp is free.
5496 On NDS32, the following registers are used:
5498 R0-R1: argument/return
5500 R15: temporary register for assembler
5501 R16: trampoline register
5502 R28: frame pointer (FP)
5503 R29: global pointer (GP)
5504 R30: link register (LP)
5505 R31: stack pointer (SP)
5506 PC: program counter (PC)
5508 ==> U-Boot will use R10 to hold a pointer to the global data
5510 NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
5511 or current versions of GCC may "optimize" the code too much.
5516 U-Boot runs in system state and uses physical addresses, i.e. the
5517 MMU is not used either for address mapping nor for memory protection.
5519 The available memory is mapped to fixed addresses using the memory
5520 controller. In this process, a contiguous block is formed for each
5521 memory type (Flash, SDRAM, SRAM), even when it consists of several
5522 physical memory banks.
5524 U-Boot is installed in the first 128 kB of the first Flash bank (on
5525 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
5526 booting and sizing and initializing DRAM, the code relocates itself
5527 to the upper end of DRAM. Immediately below the U-Boot code some
5528 memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
5529 configuration setting]. Below that, a structure with global Board
5530 Info data is placed, followed by the stack (growing downward).
5532 Additionally, some exception handler code is copied to the low 8 kB
5533 of DRAM (0x00000000 ... 0x00001FFF).
5535 So a typical memory configuration with 16 MB of DRAM could look like
5538 0x0000 0000 Exception Vector code
5541 0x0000 2000 Free for Application Use
5547 0x00FB FF20 Monitor Stack (Growing downward)
5548 0x00FB FFAC Board Info Data and permanent copy of global data
5549 0x00FC 0000 Malloc Arena
5552 0x00FE 0000 RAM Copy of Monitor Code
5553 ... eventually: LCD or video framebuffer
5554 ... eventually: pRAM (Protected RAM - unchanged by reset)
5555 0x00FF FFFF [End of RAM]
5558 System Initialization:
5559 ----------------------
5561 In the reset configuration, U-Boot starts at the reset entry point
5562 (on most PowerPC systems at address 0x00000100). Because of the reset
5563 configuration for CS0# this is a mirror of the onboard Flash memory.
5564 To be able to re-map memory U-Boot then jumps to its link address.
5565 To be able to implement the initialization code in C, a (small!)
5566 initial stack is set up in the internal Dual Ported RAM (in case CPUs
5567 which provide such a feature like MPC8xx or MPC8260), or in a locked
5568 part of the data cache. After that, U-Boot initializes the CPU core,
5569 the caches and the SIU.
5571 Next, all (potentially) available memory banks are mapped using a
5572 preliminary mapping. For example, we put them on 512 MB boundaries
5573 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
5574 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
5575 programmed for SDRAM access. Using the temporary configuration, a
5576 simple memory test is run that determines the size of the SDRAM
5579 When there is more than one SDRAM bank, and the banks are of
5580 different size, the largest is mapped first. For equal size, the first
5581 bank (CS2#) is mapped first. The first mapping is always for address
5582 0x00000000, with any additional banks following immediately to create
5583 contiguous memory starting from 0.
5585 Then, the monitor installs itself at the upper end of the SDRAM area
5586 and allocates memory for use by malloc() and for the global Board
5587 Info data; also, the exception vector code is copied to the low RAM
5588 pages, and the final stack is set up.
5590 Only after this relocation will you have a "normal" C environment;
5591 until that you are restricted in several ways, mostly because you are
5592 running from ROM, and because the code will have to be relocated to a
5596 U-Boot Porting Guide:
5597 ----------------------
5599 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
5603 int main(int argc, char *argv[])
5605 sighandler_t no_more_time;
5607 signal(SIGALRM, no_more_time);
5608 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
5610 if (available_money > available_manpower) {
5611 Pay consultant to port U-Boot;
5615 Download latest U-Boot source;
5617 Subscribe to u-boot mailing list;
5620 email("Hi, I am new to U-Boot, how do I get started?");
5623 Read the README file in the top level directory;
5624 Read http://www.denx.de/twiki/bin/view/DULG/Manual;
5625 Read applicable doc/*.README;
5626 Read the source, Luke;
5627 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
5630 if (available_money > toLocalCurrency ($2500))
5633 Add a lot of aggravation and time;
5635 if (a similar board exists) { /* hopefully... */
5636 cp -a board/<similar> board/<myboard>
5637 cp include/configs/<similar>.h include/configs/<myboard>.h
5639 Create your own board support subdirectory;
5640 Create your own board include/configs/<myboard>.h file;
5642 Edit new board/<myboard> files
5643 Edit new include/configs/<myboard>.h
5648 Add / modify source code;
5652 email("Hi, I am having problems...");
5654 Send patch file to the U-Boot email list;
5655 if (reasonable critiques)
5656 Incorporate improvements from email list code review;
5658 Defend code as written;
5664 void no_more_time (int sig)
5673 All contributions to U-Boot should conform to the Linux kernel
5674 coding style; see the file "Documentation/CodingStyle" and the script
5675 "scripts/Lindent" in your Linux kernel source directory.
5677 Source files originating from a different project (for example the
5678 MTD subsystem) are generally exempt from these guidelines and are not
5679 reformated to ease subsequent migration to newer versions of those
5682 Please note that U-Boot is implemented in C (and to some small parts in
5683 Assembler); no C++ is used, so please do not use C++ style comments (//)
5686 Please also stick to the following formatting rules:
5687 - remove any trailing white space
5688 - use TAB characters for indentation and vertical alignment, not spaces
5689 - make sure NOT to use DOS '\r\n' line feeds
5690 - do not add more than 2 consecutive empty lines to source files
5691 - do not add trailing empty lines to source files
5693 Submissions which do not conform to the standards may be returned
5694 with a request to reformat the changes.
5700 Since the number of patches for U-Boot is growing, we need to
5701 establish some rules. Submissions which do not conform to these rules
5702 may be rejected, even when they contain important and valuable stuff.
5704 Please see http://www.denx.de/wiki/U-Boot/Patches for details.
5706 Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
5707 see http://lists.denx.de/mailman/listinfo/u-boot
5709 When you send a patch, please include the following information with
5712 * For bug fixes: a description of the bug and how your patch fixes
5713 this bug. Please try to include a way of demonstrating that the
5714 patch actually fixes something.
5716 * For new features: a description of the feature and your
5719 * A CHANGELOG entry as plaintext (separate from the patch)
5721 * For major contributions, your entry to the CREDITS file
5723 * When you add support for a new board, don't forget to add this
5724 board to the MAINTAINERS file, too.
5726 * If your patch adds new configuration options, don't forget to
5727 document these in the README file.
5729 * The patch itself. If you are using git (which is *strongly*
5730 recommended) you can easily generate the patch using the
5731 "git format-patch". If you then use "git send-email" to send it to
5732 the U-Boot mailing list, you will avoid most of the common problems
5733 with some other mail clients.
5735 If you cannot use git, use "diff -purN OLD NEW". If your version of
5736 diff does not support these options, then get the latest version of
5739 The current directory when running this command shall be the parent
5740 directory of the U-Boot source tree (i. e. please make sure that
5741 your patch includes sufficient directory information for the
5744 We prefer patches as plain text. MIME attachments are discouraged,
5745 and compressed attachments must not be used.
5747 * If one logical set of modifications affects or creates several
5748 files, all these changes shall be submitted in a SINGLE patch file.
5750 * Changesets that contain different, unrelated modifications shall be
5751 submitted as SEPARATE patches, one patch per changeset.
5756 * Before sending the patch, run the MAKEALL script on your patched
5757 source tree and make sure that no errors or warnings are reported
5758 for any of the boards.
5760 * Keep your modifications to the necessary minimum: A patch
5761 containing several unrelated changes or arbitrary reformats will be
5762 returned with a request to re-formatting / split it.
5764 * If you modify existing code, make sure that your new code does not
5765 add to the memory footprint of the code ;-) Small is beautiful!
5766 When adding new features, these should compile conditionally only
5767 (using #ifdef), and the resulting code with the new feature
5768 disabled must not need more memory than the old code without your
5771 * Remember that there is a size limit of 100 kB per message on the
5772 u-boot mailing list. Bigger patches will be moderated. If they are
5773 reasonable and not too big, they will be acknowledged. But patches
5774 bigger than the size limit should be avoided.
projects / karo-tx-uboot.git / blob