2 # (C) Copyright 2000 - 2013
3 # Wolfgang Denk, DENX Software Engineering, wd@denx.de.
5 # SPDX-License-Identifier: GPL-2.0+
11 This directory contains the source code for U-Boot, a boot loader for
12 Embedded boards based on PowerPC, ARM, MIPS and several other
13 processors, which can be installed in a boot ROM and used to
14 initialize and test the hardware or to download and run application
17 The development of U-Boot is closely related to Linux: some parts of
18 the source code originate in the Linux source tree, we have some
19 header files in common, and special provision has been made to
20 support booting of Linux images.
22 Some attention has been paid to make this software easily
23 configurable and extendable. For instance, all monitor commands are
24 implemented with the same call interface, so that it's very easy to
25 add new commands. Also, instead of permanently adding rarely used
26 code (for instance hardware test utilities) to the monitor, you can
27 load and run it dynamically.
33 In general, all boards for which a configuration option exists in the
34 Makefile have been tested to some extent and can be considered
35 "working". In fact, many of them are used in production systems.
37 In case of problems see the CHANGELOG and CREDITS files to find out
38 who contributed the specific port. The boards.cfg file lists board
41 Note: There is no CHANGELOG file in the actual U-Boot source tree;
42 it can be created dynamically from the Git log using:
50 In case you have questions about, problems with or contributions for
51 U-Boot you should send a message to the U-Boot mailing list at
52 <u-boot@lists.denx.de>. There is also an archive of previous traffic
53 on the mailing list - please search the archive before asking FAQ's.
54 Please see http://lists.denx.de/pipermail/u-boot and
55 http://dir.gmane.org/gmane.comp.boot-loaders.u-boot
58 Where to get source code:
59 =========================
61 The U-Boot source code is maintained in the git repository at
62 git://www.denx.de/git/u-boot.git ; you can browse it online at
63 http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary
65 The "snapshot" links on this page allow you to download tarballs of
66 any version you might be interested in. Official releases are also
67 available for FTP download from the ftp://ftp.denx.de/pub/u-boot/
70 Pre-built (and tested) images are available from
71 ftp://ftp.denx.de/pub/u-boot/images/
77 - start from 8xxrom sources
78 - create PPCBoot project (http://sourceforge.net/projects/ppcboot)
80 - make it easier to add custom boards
81 - make it possible to add other [PowerPC] CPUs
82 - extend functions, especially:
83 * Provide extended interface to Linux boot loader
86 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot
87 - create ARMBoot project (http://sourceforge.net/projects/armboot)
88 - add other CPU families (starting with ARM)
89 - create U-Boot project (http://sourceforge.net/projects/u-boot)
90 - current project page: see http://www.denx.de/wiki/U-Boot
96 The "official" name of this project is "Das U-Boot". The spelling
97 "U-Boot" shall be used in all written text (documentation, comments
98 in source files etc.). Example:
100 This is the README file for the U-Boot project.
102 File names etc. shall be based on the string "u-boot". Examples:
104 include/asm-ppc/u-boot.h
106 #include <asm/u-boot.h>
108 Variable names, preprocessor constants etc. shall be either based on
109 the string "u_boot" or on "U_BOOT". Example:
111 U_BOOT_VERSION u_boot_logo
112 IH_OS_U_BOOT u_boot_hush_start
118 Starting with the release in October 2008, the names of the releases
119 were changed from numerical release numbers without deeper meaning
120 into a time stamp based numbering. Regular releases are identified by
121 names consisting of the calendar year and month of the release date.
122 Additional fields (if present) indicate release candidates or bug fix
123 releases in "stable" maintenance trees.
126 U-Boot v2009.11 - Release November 2009
127 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree
128 U-Boot v2010.09-rc1 - Release candiate 1 for September 2010 release
134 /arch Architecture specific files
135 /arm Files generic to ARM architecture
136 /cpu CPU specific files
137 /arm720t Files specific to ARM 720 CPUs
138 /arm920t Files specific to ARM 920 CPUs
139 /at91 Files specific to Atmel AT91RM9200 CPU
140 /imx Files specific to Freescale MC9328 i.MX CPUs
141 /s3c24x0 Files specific to Samsung S3C24X0 CPUs
142 /arm926ejs Files specific to ARM 926 CPUs
143 /arm1136 Files specific to ARM 1136 CPUs
144 /ixp Files specific to Intel XScale IXP CPUs
145 /pxa Files specific to Intel XScale PXA CPUs
146 /sa1100 Files specific to Intel StrongARM SA1100 CPUs
147 /lib Architecture specific library files
148 /avr32 Files generic to AVR32 architecture
149 /cpu CPU specific files
150 /lib Architecture specific library files
151 /blackfin Files generic to Analog Devices Blackfin architecture
152 /cpu CPU specific files
153 /lib Architecture specific library files
154 /m68k Files generic to m68k architecture
155 /cpu CPU specific files
156 /mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs
157 /mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs
158 /mcf532x Files specific to Freescale ColdFire MCF5329 CPUs
159 /mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs
160 /mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs
161 /lib Architecture specific library files
162 /microblaze Files generic to microblaze architecture
163 /cpu CPU specific files
164 /lib Architecture specific library files
165 /mips Files generic to MIPS architecture
166 /cpu CPU specific files
167 /mips32 Files specific to MIPS32 CPUs
168 /xburst Files specific to Ingenic XBurst CPUs
169 /lib Architecture specific library files
170 /nds32 Files generic to NDS32 architecture
171 /cpu CPU specific files
172 /n1213 Files specific to Andes Technology N1213 CPUs
173 /lib Architecture specific library files
174 /nios2 Files generic to Altera NIOS2 architecture
175 /cpu CPU specific files
176 /lib Architecture specific library files
177 /openrisc Files generic to OpenRISC architecture
178 /cpu CPU specific files
179 /lib Architecture specific library files
180 /powerpc Files generic to PowerPC architecture
181 /cpu CPU specific files
182 /74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs
183 /mpc5xx Files specific to Freescale MPC5xx CPUs
184 /mpc5xxx Files specific to Freescale MPC5xxx CPUs
185 /mpc8xx Files specific to Freescale MPC8xx CPUs
186 /mpc824x Files specific to Freescale MPC824x CPUs
187 /mpc8260 Files specific to Freescale MPC8260 CPUs
188 /mpc85xx Files specific to Freescale MPC85xx CPUs
189 /ppc4xx Files specific to AMCC PowerPC 4xx CPUs
190 /lib Architecture specific library files
191 /sh Files generic to SH architecture
192 /cpu CPU specific files
193 /sh2 Files specific to sh2 CPUs
194 /sh3 Files specific to sh3 CPUs
195 /sh4 Files specific to sh4 CPUs
196 /lib Architecture specific library files
197 /sparc Files generic to SPARC architecture
198 /cpu CPU specific files
199 /leon2 Files specific to Gaisler LEON2 SPARC CPU
200 /leon3 Files specific to Gaisler LEON3 SPARC CPU
201 /lib Architecture specific library files
202 /x86 Files generic to x86 architecture
203 /cpu CPU specific files
204 /lib Architecture specific library files
205 /api Machine/arch independent API for external apps
206 /board Board dependent files
207 /common Misc architecture independent functions
208 /disk Code for disk drive partition handling
209 /doc Documentation (don't expect too much)
210 /drivers Commonly used device drivers
211 /dts Contains Makefile for building internal U-Boot fdt.
212 /examples Example code for standalone applications, etc.
213 /fs Filesystem code (cramfs, ext2, jffs2, etc.)
214 /include Header Files
215 /lib Files generic to all architectures
216 /libfdt Library files to support flattened device trees
217 /lzma Library files to support LZMA decompression
218 /lzo Library files to support LZO decompression
220 /post Power On Self Test
221 /spl Secondary Program Loader framework
222 /tools Tools to build S-Record or U-Boot images, etc.
224 Software Configuration:
225 =======================
227 Configuration is usually done using C preprocessor defines; the
228 rationale behind that is to avoid dead code whenever possible.
230 There are two classes of configuration variables:
232 * Configuration _OPTIONS_:
233 These are selectable by the user and have names beginning with
236 * Configuration _SETTINGS_:
237 These depend on the hardware etc. and should not be meddled with if
238 you don't know what you're doing; they have names beginning with
241 Later we will add a configuration tool - probably similar to or even
242 identical to what's used for the Linux kernel. Right now, we have to
243 do the configuration by hand, which means creating some symbolic
244 links and editing some configuration files. We use the TQM8xxL boards
248 Selection of Processor Architecture and Board Type:
249 ---------------------------------------------------
251 For all supported boards there are ready-to-use default
252 configurations available; just type "make <board_name>_config".
254 Example: For a TQM823L module type:
259 For the Cogent platform, you need to specify the CPU type as well;
260 e.g. "make cogent_mpc8xx_config". And also configure the cogent
261 directory according to the instructions in cogent/README.
264 Configuration Options:
265 ----------------------
267 Configuration depends on the combination of board and CPU type; all
268 such information is kept in a configuration file
269 "include/configs/<board_name>.h".
271 Example: For a TQM823L module, all configuration settings are in
272 "include/configs/TQM823L.h".
275 Many of the options are named exactly as the corresponding Linux
276 kernel configuration options. The intention is to make it easier to
277 build a config tool - later.
280 The following options need to be configured:
282 - CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
284 - Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
286 - CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined)
287 Define exactly one, e.g. CONFIG_ATSTK1002
289 - CPU Module Type: (if CONFIG_COGENT is defined)
290 Define exactly one of
292 --- FIXME --- not tested yet:
293 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
294 CONFIG_CMA287_23, CONFIG_CMA287_50
296 - Motherboard Type: (if CONFIG_COGENT is defined)
297 Define exactly one of
298 CONFIG_CMA101, CONFIG_CMA102
300 - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
301 Define one or more of
304 - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
305 Define one or more of
306 CONFIG_LCD_HEARTBEAT - update a character position on
307 the LCD display every second with
310 - Board flavour: (if CONFIG_MPC8260ADS is defined)
313 CONFIG_SYS_8260ADS - original MPC8260ADS
314 CONFIG_SYS_8266ADS - MPC8266ADS
315 CONFIG_SYS_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR
316 CONFIG_SYS_8272ADS - MPC8272ADS
318 - Marvell Family Member
319 CONFIG_SYS_MVFS - define it if you want to enable
320 multiple fs option at one time
321 for marvell soc family
323 - MPC824X Family Member (if CONFIG_MPC824X is defined)
324 Define exactly one of
325 CONFIG_MPC8240, CONFIG_MPC8245
327 - 8xx CPU Options: (if using an MPC8xx CPU)
328 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if
329 get_gclk_freq() cannot work
330 e.g. if there is no 32KHz
331 reference PIT/RTC clock
332 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK
335 - 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
336 CONFIG_SYS_8xx_CPUCLK_MIN
337 CONFIG_SYS_8xx_CPUCLK_MAX
338 CONFIG_8xx_CPUCLK_DEFAULT
339 See doc/README.MPC866
341 CONFIG_SYS_MEASURE_CPUCLK
343 Define this to measure the actual CPU clock instead
344 of relying on the correctness of the configured
345 values. Mostly useful for board bringup to make sure
346 the PLL is locked at the intended frequency. Note
347 that this requires a (stable) reference clock (32 kHz
348 RTC clock or CONFIG_SYS_8XX_XIN)
350 CONFIG_SYS_DELAYED_ICACHE
352 Define this option if you want to enable the
353 ICache only when Code runs from RAM.
358 Specifies that the core is a 64-bit PowerPC implementation (implements
359 the "64" category of the Power ISA). This is necessary for ePAPR
360 compliance, among other possible reasons.
362 CONFIG_SYS_FSL_TBCLK_DIV
364 Defines the core time base clock divider ratio compared to the
365 system clock. On most PQ3 devices this is 8, on newer QorIQ
366 devices it can be 16 or 32. The ratio varies from SoC to Soc.
368 CONFIG_SYS_FSL_PCIE_COMPAT
370 Defines the string to utilize when trying to match PCIe device
371 tree nodes for the given platform.
373 CONFIG_SYS_PPC_E500_DEBUG_TLB
375 Enables a temporary TLB entry to be used during boot to work
376 around limitations in e500v1 and e500v2 external debugger
377 support. This reduces the portions of the boot code where
378 breakpoints and single stepping do not work. The value of this
379 symbol should be set to the TLB1 entry to be used for this
382 CONFIG_SYS_FSL_ERRATUM_A004510
384 Enables a workaround for erratum A004510. If set,
385 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and
386 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set.
388 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV
389 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional)
391 Defines one or two SoC revisions (low 8 bits of SVR)
392 for which the A004510 workaround should be applied.
394 The rest of SVR is either not relevant to the decision
395 of whether the erratum is present (e.g. p2040 versus
396 p2041) or is implied by the build target, which controls
397 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set.
399 See Freescale App Note 4493 for more information about
402 CONFIG_A003399_NOR_WORKAROUND
403 Enables a workaround for IFC erratum A003399. It is only
404 requred during NOR boot.
406 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY
408 This is the value to write into CCSR offset 0x18600
409 according to the A004510 workaround.
411 CONFIG_SYS_FSL_DSP_DDR_ADDR
412 This value denotes start offset of DDR memory which is
413 connected exclusively to the DSP cores.
415 CONFIG_SYS_FSL_DSP_M2_RAM_ADDR
416 This value denotes start offset of M2 memory
417 which is directly connected to the DSP core.
419 CONFIG_SYS_FSL_DSP_M3_RAM_ADDR
420 This value denotes start offset of M3 memory which is directly
421 connected to the DSP core.
423 CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT
424 This value denotes start offset of DSP CCSR space.
426 CONFIG_SYS_FSL_DDR_EMU
427 Specify emulator support for DDR. Some DDR features such as
428 deskew training are not available.
430 - Generic CPU options:
431 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN
433 Defines the endianess of the CPU. Implementation of those
434 values is arch specific.
436 - Intel Monahans options:
437 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO
439 Defines the Monahans run mode to oscillator
440 ratio. Valid values are 8, 16, 24, 31. The core
441 frequency is this value multiplied by 13 MHz.
443 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO
445 Defines the Monahans turbo mode to oscillator
446 ratio. Valid values are 1 (default if undefined) and
447 2. The core frequency as calculated above is multiplied
451 CONFIG_SYS_INIT_SP_OFFSET
453 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack
454 pointer. This is needed for the temporary stack before
457 CONFIG_SYS_MIPS_CACHE_MODE
459 Cache operation mode for the MIPS CPU.
460 See also arch/mips/include/asm/mipsregs.h.
462 CONF_CM_CACHABLE_NO_WA
465 CONF_CM_CACHABLE_NONCOHERENT
469 CONF_CM_CACHABLE_ACCELERATED
471 CONFIG_SYS_XWAY_EBU_BOOTCFG
473 Special option for Lantiq XWAY SoCs for booting from NOR flash.
474 See also arch/mips/cpu/mips32/start.S.
476 CONFIG_XWAY_SWAP_BYTES
478 Enable compilation of tools/xway-swap-bytes needed for Lantiq
479 XWAY SoCs for booting from NOR flash. The U-Boot image needs to
480 be swapped if a flash programmer is used.
483 CONFIG_SYS_EXCEPTION_VECTORS_HIGH
485 Select high exception vectors of the ARM core, e.g., do not
486 clear the V bit of the c1 register of CP15.
488 CONFIG_SYS_THUMB_BUILD
490 Use this flag to build U-Boot using the Thumb instruction
491 set for ARM architectures. Thumb instruction set provides
492 better code density. For ARM architectures that support
493 Thumb2 this flag will result in Thumb2 code generated by
496 CONFIG_ARM_ERRATA_716044
497 CONFIG_ARM_ERRATA_742230
498 CONFIG_ARM_ERRATA_743622
499 CONFIG_ARM_ERRATA_751472
501 If set, the workarounds for these ARM errata are applied early
502 during U-Boot startup. Note that these options force the
503 workarounds to be applied; no CPU-type/version detection
504 exists, unlike the similar options in the Linux kernel. Do not
505 set these options unless they apply!
510 The frequency of the timer returned by get_timer().
511 get_timer() must operate in milliseconds and this CONFIG
512 option must be set to 1000.
514 - Linux Kernel Interface:
517 U-Boot stores all clock information in Hz
518 internally. For binary compatibility with older Linux
519 kernels (which expect the clocks passed in the
520 bd_info data to be in MHz) the environment variable
521 "clocks_in_mhz" can be defined so that U-Boot
522 converts clock data to MHZ before passing it to the
524 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
525 "clocks_in_mhz=1" is automatically included in the
528 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
530 When transferring memsize parameter to linux, some versions
531 expect it to be in bytes, others in MB.
532 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
536 New kernel versions are expecting firmware settings to be
537 passed using flattened device trees (based on open firmware
541 * New libfdt-based support
542 * Adds the "fdt" command
543 * The bootm command automatically updates the fdt
545 OF_CPU - The proper name of the cpus node (only required for
546 MPC512X and MPC5xxx based boards).
547 OF_SOC - The proper name of the soc node (only required for
548 MPC512X and MPC5xxx based boards).
549 OF_TBCLK - The timebase frequency.
550 OF_STDOUT_PATH - The path to the console device
552 boards with QUICC Engines require OF_QE to set UCC MAC
555 CONFIG_OF_BOARD_SETUP
557 Board code has addition modification that it wants to make
558 to the flat device tree before handing it off to the kernel
562 This define fills in the correct boot CPU in the boot
563 param header, the default value is zero if undefined.
567 U-Boot can detect if an IDE device is present or not.
568 If not, and this new config option is activated, U-Boot
569 removes the ATA node from the DTS before booting Linux,
570 so the Linux IDE driver does not probe the device and
571 crash. This is needed for buggy hardware (uc101) where
572 no pull down resistor is connected to the signal IDE5V_DD7.
574 CONFIG_MACH_TYPE [relevant for ARM only][mandatory]
576 This setting is mandatory for all boards that have only one
577 machine type and must be used to specify the machine type
578 number as it appears in the ARM machine registry
579 (see http://www.arm.linux.org.uk/developer/machines/).
580 Only boards that have multiple machine types supported
581 in a single configuration file and the machine type is
582 runtime discoverable, do not have to use this setting.
584 - vxWorks boot parameters:
586 bootvx constructs a valid bootline using the following
587 environments variables: bootfile, ipaddr, serverip, hostname.
588 It loads the vxWorks image pointed bootfile.
590 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name
591 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address
592 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server
593 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters
595 CONFIG_SYS_VXWORKS_ADD_PARAMS
597 Add it at the end of the bootline. E.g "u=username pw=secret"
599 Note: If a "bootargs" environment is defined, it will overwride
600 the defaults discussed just above.
602 - Cache Configuration:
603 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot
604 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot
605 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot
607 - Cache Configuration for ARM:
608 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache
610 CONFIG_SYS_PL310_BASE - Physical base address of PL310
611 controller register space
616 Define this if you want support for Amba PrimeCell PL010 UARTs.
620 Define this if you want support for Amba PrimeCell PL011 UARTs.
624 If you have Amba PrimeCell PL011 UARTs, set this variable to
625 the clock speed of the UARTs.
629 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
630 define this to a list of base addresses for each (supported)
631 port. See e.g. include/configs/versatile.h
633 CONFIG_PL011_SERIAL_RLCR
635 Some vendor versions of PL011 serial ports (e.g. ST-Ericsson U8500)
636 have separate receive and transmit line control registers. Set
637 this variable to initialize the extra register.
639 CONFIG_PL011_SERIAL_FLUSH_ON_INIT
641 On some platforms (e.g. U8500) U-Boot is loaded by a second stage
642 boot loader that has already initialized the UART. Define this
643 variable to flush the UART at init time.
647 Depending on board, define exactly one serial port
648 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
649 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
650 console by defining CONFIG_8xx_CONS_NONE
652 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
653 port routines must be defined elsewhere
654 (i.e. serial_init(), serial_getc(), ...)
657 Enables console device for a color framebuffer. Needs following
658 defines (cf. smiLynxEM, i8042)
659 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
661 VIDEO_HW_RECTFILL graphic chip supports
664 VIDEO_HW_BITBLT graphic chip supports
665 bit-blit (cf. smiLynxEM)
666 VIDEO_VISIBLE_COLS visible pixel columns
668 VIDEO_VISIBLE_ROWS visible pixel rows
669 VIDEO_PIXEL_SIZE bytes per pixel
670 VIDEO_DATA_FORMAT graphic data format
671 (0-5, cf. cfb_console.c)
672 VIDEO_FB_ADRS framebuffer address
673 VIDEO_KBD_INIT_FCT keyboard int fct
674 (i.e. i8042_kbd_init())
675 VIDEO_TSTC_FCT test char fct
677 VIDEO_GETC_FCT get char fct
679 CONFIG_CONSOLE_CURSOR cursor drawing on/off
680 (requires blink timer
682 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
683 CONFIG_CONSOLE_TIME display time/date info in
685 (requires CONFIG_CMD_DATE)
686 CONFIG_VIDEO_LOGO display Linux logo in
688 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
689 linux_logo.h for logo.
690 Requires CONFIG_VIDEO_LOGO
691 CONFIG_CONSOLE_EXTRA_INFO
692 additional board info beside
695 When CONFIG_CFB_CONSOLE_ANSI is defined, console will support
696 a limited number of ANSI escape sequences (cursor control,
697 erase functions and limited graphics rendition control).
699 When CONFIG_CFB_CONSOLE is defined, video console is
700 default i/o. Serial console can be forced with
701 environment 'console=serial'.
703 When CONFIG_SILENT_CONSOLE is defined, all console
704 messages (by U-Boot and Linux!) can be silenced with
705 the "silent" environment variable. See
706 doc/README.silent for more information.
709 CONFIG_BAUDRATE - in bps
710 Select one of the baudrates listed in
711 CONFIG_SYS_BAUDRATE_TABLE, see below.
712 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale
714 - Console Rx buffer length
715 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define
716 the maximum receive buffer length for the SMC.
717 This option is actual only for 82xx and 8xx possible.
718 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE
719 must be defined, to setup the maximum idle timeout for
722 - Pre-Console Buffer:
723 Prior to the console being initialised (i.e. serial UART
724 initialised etc) all console output is silently discarded.
725 Defining CONFIG_PRE_CONSOLE_BUFFER will cause U-Boot to
726 buffer any console messages prior to the console being
727 initialised to a buffer of size CONFIG_PRE_CON_BUF_SZ
728 bytes located at CONFIG_PRE_CON_BUF_ADDR. The buffer is
729 a circular buffer, so if more than CONFIG_PRE_CON_BUF_SZ
730 bytes are output before the console is initialised, the
731 earlier bytes are discarded.
733 'Sane' compilers will generate smaller code if
734 CONFIG_PRE_CON_BUF_SZ is a power of 2
736 - Safe printf() functions
737 Define CONFIG_SYS_VSNPRINTF to compile in safe versions of
738 the printf() functions. These are defined in
739 include/vsprintf.h and include snprintf(), vsnprintf() and
740 so on. Code size increase is approximately 300-500 bytes.
741 If this option is not given then these functions will
742 silently discard their buffer size argument - this means
743 you are not getting any overflow checking in this case.
745 - Boot Delay: CONFIG_BOOTDELAY - in seconds
746 Delay before automatically booting the default image;
747 set to -1 to disable autoboot.
748 set to -2 to autoboot with no delay and not check for abort
749 (even when CONFIG_ZERO_BOOTDELAY_CHECK is defined).
751 See doc/README.autoboot for these options that
752 work with CONFIG_BOOTDELAY. None are required.
753 CONFIG_BOOT_RETRY_TIME
754 CONFIG_BOOT_RETRY_MIN
755 CONFIG_AUTOBOOT_KEYED
756 CONFIG_AUTOBOOT_PROMPT
757 CONFIG_AUTOBOOT_DELAY_STR
758 CONFIG_AUTOBOOT_STOP_STR
759 CONFIG_AUTOBOOT_DELAY_STR2
760 CONFIG_AUTOBOOT_STOP_STR2
761 CONFIG_ZERO_BOOTDELAY_CHECK
762 CONFIG_RESET_TO_RETRY
766 Only needed when CONFIG_BOOTDELAY is enabled;
767 define a command string that is automatically executed
768 when no character is read on the console interface
769 within "Boot Delay" after reset.
772 This can be used to pass arguments to the bootm
773 command. The value of CONFIG_BOOTARGS goes into the
774 environment value "bootargs".
776 CONFIG_RAMBOOT and CONFIG_NFSBOOT
777 The value of these goes into the environment as
778 "ramboot" and "nfsboot" respectively, and can be used
779 as a convenience, when switching between booting from
785 When this option is #defined, the existence of the
786 environment variable "preboot" will be checked
787 immediately before starting the CONFIG_BOOTDELAY
788 countdown and/or running the auto-boot command resp.
789 entering interactive mode.
791 This feature is especially useful when "preboot" is
792 automatically generated or modified. For an example
793 see the LWMON board specific code: here "preboot" is
794 modified when the user holds down a certain
795 combination of keys on the (special) keyboard when
798 - Serial Download Echo Mode:
800 If defined to 1, all characters received during a
801 serial download (using the "loads" command) are
802 echoed back. This might be needed by some terminal
803 emulations (like "cu"), but may as well just take
804 time on others. This setting #define's the initial
805 value of the "loads_echo" environment variable.
807 - Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
809 Select one of the baudrates listed in
810 CONFIG_SYS_BAUDRATE_TABLE, see below.
813 Monitor commands can be included or excluded
814 from the build by using the #include files
815 <config_cmd_all.h> and #undef'ing unwanted
816 commands, or using <config_cmd_default.h>
817 and augmenting with additional #define's
820 The default command configuration includes all commands
821 except those marked below with a "*".
823 CONFIG_CMD_ASKENV * ask for env variable
824 CONFIG_CMD_BDI bdinfo
825 CONFIG_CMD_BEDBUG * Include BedBug Debugger
826 CONFIG_CMD_BMP * BMP support
827 CONFIG_CMD_BSP * Board specific commands
828 CONFIG_CMD_BOOTD bootd
829 CONFIG_CMD_CACHE * icache, dcache
830 CONFIG_CMD_CONSOLE coninfo
831 CONFIG_CMD_CRC32 * crc32
832 CONFIG_CMD_DATE * support for RTC, date/time...
833 CONFIG_CMD_DHCP * DHCP support
834 CONFIG_CMD_DIAG * Diagnostics
835 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands
836 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command
837 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd
838 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command
839 CONFIG_CMD_DTT * Digital Therm and Thermostat
840 CONFIG_CMD_ECHO echo arguments
841 CONFIG_CMD_EDITENV edit env variable
842 CONFIG_CMD_EEPROM * EEPROM read/write support
843 CONFIG_CMD_ELF * bootelf, bootvx
844 CONFIG_CMD_ENV_CALLBACK * display details about env callbacks
845 CONFIG_CMD_ENV_FLAGS * display details about env flags
846 CONFIG_CMD_EXPORTENV * export the environment
847 CONFIG_CMD_EXT2 * ext2 command support
848 CONFIG_CMD_EXT4 * ext4 command support
849 CONFIG_CMD_SAVEENV saveenv
850 CONFIG_CMD_FDC * Floppy Disk Support
851 CONFIG_CMD_FAT * FAT command support
852 CONFIG_CMD_FDOS * Dos diskette Support
853 CONFIG_CMD_FLASH flinfo, erase, protect
854 CONFIG_CMD_FPGA FPGA device initialization support
855 CONFIG_CMD_FUSE * Device fuse support
856 CONFIG_CMD_GETTIME * Get time since boot
857 CONFIG_CMD_GO * the 'go' command (exec code)
858 CONFIG_CMD_GREPENV * search environment
859 CONFIG_CMD_HASH * calculate hash / digest
860 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control
861 CONFIG_CMD_I2C * I2C serial bus support
862 CONFIG_CMD_IDE * IDE harddisk support
863 CONFIG_CMD_IMI iminfo
864 CONFIG_CMD_IMLS List all images found in NOR flash
865 CONFIG_CMD_IMLS_NAND * List all images found in NAND flash
866 CONFIG_CMD_IMMAP * IMMR dump support
867 CONFIG_CMD_IMPORTENV * import an environment
868 CONFIG_CMD_INI * import data from an ini file into the env
869 CONFIG_CMD_IRQ * irqinfo
870 CONFIG_CMD_ITEST Integer/string test of 2 values
871 CONFIG_CMD_JFFS2 * JFFS2 Support
872 CONFIG_CMD_KGDB * kgdb
873 CONFIG_CMD_LDRINFO * ldrinfo (display Blackfin loader)
874 CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration
876 CONFIG_CMD_LOADB loadb
877 CONFIG_CMD_LOADS loads
878 CONFIG_CMD_MD5SUM * print md5 message digest
879 (requires CONFIG_CMD_MEMORY and CONFIG_MD5)
880 CONFIG_CMD_MEMINFO * Display detailed memory information
881 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
883 CONFIG_CMD_MEMTEST * mtest
884 CONFIG_CMD_MISC Misc functions like sleep etc
885 CONFIG_CMD_MMC * MMC memory mapped support
886 CONFIG_CMD_MII * MII utility commands
887 CONFIG_CMD_MTDPARTS * MTD partition support
888 CONFIG_CMD_NAND * NAND support
889 CONFIG_CMD_NET bootp, tftpboot, rarpboot
890 CONFIG_CMD_NFS NFS support
891 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands
892 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command
893 CONFIG_CMD_PCI * pciinfo
894 CONFIG_CMD_PCMCIA * PCMCIA support
895 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network
897 CONFIG_CMD_PORTIO * Port I/O
898 CONFIG_CMD_READ * Read raw data from partition
899 CONFIG_CMD_REGINFO * Register dump
900 CONFIG_CMD_RUN run command in env variable
901 CONFIG_CMD_SANDBOX * sb command to access sandbox features
902 CONFIG_CMD_SAVES * save S record dump
903 CONFIG_CMD_SCSI * SCSI Support
904 CONFIG_CMD_SDRAM * print SDRAM configuration information
905 (requires CONFIG_CMD_I2C)
906 CONFIG_CMD_SETGETDCR Support for DCR Register access
908 CONFIG_CMD_SF * Read/write/erase SPI NOR flash
909 CONFIG_CMD_SHA1SUM * print sha1 memory digest
910 (requires CONFIG_CMD_MEMORY)
911 CONFIG_CMD_SOFTSWITCH * Soft switch setting command for BF60x
912 CONFIG_CMD_SOURCE "source" command Support
913 CONFIG_CMD_SPI * SPI serial bus support
914 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode
915 CONFIG_CMD_TFTPPUT * TFTP put command (upload)
916 CONFIG_CMD_TIME * run command and report execution time (ARM specific)
917 CONFIG_CMD_TIMER * access to the system tick timer
918 CONFIG_CMD_USB * USB support
919 CONFIG_CMD_CDP * Cisco Discover Protocol support
920 CONFIG_CMD_MFSL * Microblaze FSL support
921 CONFIG_CMD_XIMG Load part of Multi Image
924 EXAMPLE: If you want all functions except of network
925 support you can write:
927 #include "config_cmd_all.h"
928 #undef CONFIG_CMD_NET
931 fdt (flattened device tree) command: CONFIG_OF_LIBFDT
933 Note: Don't enable the "icache" and "dcache" commands
934 (configuration option CONFIG_CMD_CACHE) unless you know
935 what you (and your U-Boot users) are doing. Data
936 cache cannot be enabled on systems like the 8xx or
937 8260 (where accesses to the IMMR region must be
938 uncached), and it cannot be disabled on all other
939 systems where we (mis-) use the data cache to hold an
940 initial stack and some data.
943 XXX - this list needs to get updated!
945 - Regular expression support:
947 If this variable is defined, U-Boot is linked against
948 the SLRE (Super Light Regular Expression) library,
949 which adds regex support to some commands, as for
950 example "env grep" and "setexpr".
954 If this variable is defined, U-Boot will use a device tree
955 to configure its devices, instead of relying on statically
956 compiled #defines in the board file. This option is
957 experimental and only available on a few boards. The device
958 tree is available in the global data as gd->fdt_blob.
960 U-Boot needs to get its device tree from somewhere. This can
961 be done using one of the two options below:
964 If this variable is defined, U-Boot will embed a device tree
965 binary in its image. This device tree file should be in the
966 board directory and called <soc>-<board>.dts. The binary file
967 is then picked up in board_init_f() and made available through
968 the global data structure as gd->blob.
971 If this variable is defined, U-Boot will build a device tree
972 binary. It will be called u-boot.dtb. Architecture-specific
973 code will locate it at run-time. Generally this works by:
975 cat u-boot.bin u-boot.dtb >image.bin
977 and in fact, U-Boot does this for you, creating a file called
978 u-boot-dtb.bin which is useful in the common case. You can
979 still use the individual files if you need something more
984 If this variable is defined, it enables watchdog
985 support for the SoC. There must be support in the SoC
986 specific code for a watchdog. For the 8xx and 8260
987 CPUs, the SIU Watchdog feature is enabled in the SYPCR
988 register. When supported for a specific SoC is
989 available, then no further board specific code should
993 When using a watchdog circuitry external to the used
994 SoC, then define this variable and provide board
995 specific code for the "hw_watchdog_reset" function.
998 CONFIG_VERSION_VARIABLE
999 If this variable is defined, an environment variable
1000 named "ver" is created by U-Boot showing the U-Boot
1001 version as printed by the "version" command.
1002 Any change to this variable will be reverted at the
1007 When CONFIG_CMD_DATE is selected, the type of the RTC
1008 has to be selected, too. Define exactly one of the
1011 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
1012 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
1013 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC
1014 CONFIG_RTC_MC146818 - use MC146818 RTC
1015 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
1016 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
1017 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
1018 CONFIG_RTC_DS164x - use Dallas DS164x RTC
1019 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
1020 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
1021 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
1022 CONFIG_SYS_RV3029_TCR - enable trickle charger on
1025 Note that if the RTC uses I2C, then the I2C interface
1026 must also be configured. See I2C Support, below.
1029 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
1030 CONFIG_PCA953X_INFO - enable pca953x info command
1032 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
1033 chip-ngpio pairs that tell the PCA953X driver the number of
1034 pins supported by a particular chip.
1036 Note that if the GPIO device uses I2C, then the I2C interface
1037 must also be configured. See I2C Support, below.
1039 - Timestamp Support:
1041 When CONFIG_TIMESTAMP is selected, the timestamp
1042 (date and time) of an image is printed by image
1043 commands like bootm or iminfo. This option is
1044 automatically enabled when you select CONFIG_CMD_DATE .
1046 - Partition Labels (disklabels) Supported:
1047 Zero or more of the following:
1048 CONFIG_MAC_PARTITION Apple's MacOS partition table.
1049 CONFIG_DOS_PARTITION MS Dos partition table, traditional on the
1050 Intel architecture, USB sticks, etc.
1051 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc.
1052 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the
1053 bootloader. Note 2TB partition limit; see
1055 CONFIG_MTD_PARTITIONS Memory Technology Device partition table.
1057 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or
1058 CONFIG_CMD_SCSI) you must configure support for at
1059 least one non-MTD partition type as well.
1062 CONFIG_IDE_RESET_ROUTINE - this is defined in several
1063 board configurations files but used nowhere!
1065 CONFIG_IDE_RESET - is this is defined, IDE Reset will
1066 be performed by calling the function
1067 ide_set_reset(int reset)
1068 which has to be defined in a board specific file
1073 Set this to enable ATAPI support.
1078 Set this to enable support for disks larger than 137GB
1079 Also look at CONFIG_SYS_64BIT_LBA.
1080 Whithout these , LBA48 support uses 32bit variables and will 'only'
1081 support disks up to 2.1TB.
1083 CONFIG_SYS_64BIT_LBA:
1084 When enabled, makes the IDE subsystem use 64bit sector addresses.
1088 At the moment only there is only support for the
1089 SYM53C8XX SCSI controller; define
1090 CONFIG_SCSI_SYM53C8XX to enable it.
1092 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
1093 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
1094 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
1095 maximum numbers of LUNs, SCSI ID's and target
1097 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
1099 The environment variable 'scsidevs' is set to the number of
1100 SCSI devices found during the last scan.
1102 - NETWORK Support (PCI):
1104 Support for Intel 8254x/8257x gigabit chips.
1107 Utility code for direct access to the SPI bus on Intel 8257x.
1108 This does not do anything useful unless you set at least one
1109 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC.
1111 CONFIG_E1000_SPI_GENERIC
1112 Allow generic access to the SPI bus on the Intel 8257x, for
1113 example with the "sspi" command.
1116 Management command for E1000 devices. When used on devices
1117 with SPI support you can reprogram the EEPROM from U-Boot.
1119 CONFIG_E1000_FALLBACK_MAC
1120 default MAC for empty EEPROM after production.
1123 Support for Intel 82557/82559/82559ER chips.
1124 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
1125 write routine for first time initialisation.
1128 Support for Digital 2114x chips.
1129 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
1130 modem chip initialisation (KS8761/QS6611).
1133 Support for National dp83815 chips.
1136 Support for National dp8382[01] gigabit chips.
1138 - NETWORK Support (other):
1140 CONFIG_DRIVER_AT91EMAC
1141 Support for AT91RM9200 EMAC.
1144 Define this to use reduced MII inteface
1146 CONFIG_DRIVER_AT91EMAC_QUIET
1147 If this defined, the driver is quiet.
1148 The driver doen't show link status messages.
1150 CONFIG_CALXEDA_XGMAC
1151 Support for the Calxeda XGMAC device
1154 Support for SMSC's LAN91C96 chips.
1156 CONFIG_LAN91C96_BASE
1157 Define this to hold the physical address
1158 of the LAN91C96's I/O space
1160 CONFIG_LAN91C96_USE_32_BIT
1161 Define this to enable 32 bit addressing
1164 Support for SMSC's LAN91C111 chip
1166 CONFIG_SMC91111_BASE
1167 Define this to hold the physical address
1168 of the device (I/O space)
1170 CONFIG_SMC_USE_32_BIT
1171 Define this if data bus is 32 bits
1173 CONFIG_SMC_USE_IOFUNCS
1174 Define this to use i/o functions instead of macros
1175 (some hardware wont work with macros)
1177 CONFIG_DRIVER_TI_EMAC
1178 Support for davinci emac
1180 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT
1181 Define this if you have more then 3 PHYs.
1184 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
1186 CONFIG_FTGMAC100_EGIGA
1187 Define this to use GE link update with gigabit PHY.
1188 Define this if FTGMAC100 is connected to gigabit PHY.
1189 If your system has 10/100 PHY only, it might not occur
1190 wrong behavior. Because PHY usually return timeout or
1191 useless data when polling gigabit status and gigabit
1192 control registers. This behavior won't affect the
1193 correctnessof 10/100 link speed update.
1196 Support for SMSC's LAN911x and LAN921x chips
1199 Define this to hold the physical address
1200 of the device (I/O space)
1202 CONFIG_SMC911X_32_BIT
1203 Define this if data bus is 32 bits
1205 CONFIG_SMC911X_16_BIT
1206 Define this if data bus is 16 bits. If your processor
1207 automatically converts one 32 bit word to two 16 bit
1208 words you may also try CONFIG_SMC911X_32_BIT.
1211 Support for Renesas on-chip Ethernet controller
1213 CONFIG_SH_ETHER_USE_PORT
1214 Define the number of ports to be used
1216 CONFIG_SH_ETHER_PHY_ADDR
1217 Define the ETH PHY's address
1219 CONFIG_SH_ETHER_CACHE_WRITEBACK
1220 If this option is set, the driver enables cache flush.
1224 Support TPM devices.
1227 Support for i2c bus TPM devices. Only one device
1228 per system is supported at this time.
1230 CONFIG_TPM_TIS_I2C_BUS_NUMBER
1231 Define the the i2c bus number for the TPM device
1233 CONFIG_TPM_TIS_I2C_SLAVE_ADDRESS
1234 Define the TPM's address on the i2c bus
1236 CONFIG_TPM_TIS_I2C_BURST_LIMITATION
1237 Define the burst count bytes upper limit
1239 CONFIG_TPM_ATMEL_TWI
1240 Support for Atmel TWI TPM device. Requires I2C support.
1243 Support for generic parallel port TPM devices. Only one device
1244 per system is supported at this time.
1246 CONFIG_TPM_TIS_BASE_ADDRESS
1247 Base address where the generic TPM device is mapped
1248 to. Contemporary x86 systems usually map it at
1252 Add tpm monitor functions.
1253 Requires CONFIG_TPM. If CONFIG_TPM_AUTH_SESSIONS is set, also
1254 provides monitor access to authorized functions.
1257 Define this to enable the TPM support library which provides
1258 functional interfaces to some TPM commands.
1259 Requires support for a TPM device.
1261 CONFIG_TPM_AUTH_SESSIONS
1262 Define this to enable authorized functions in the TPM library.
1263 Requires CONFIG_TPM and CONFIG_SHA1.
1266 At the moment only the UHCI host controller is
1267 supported (PIP405, MIP405, MPC5200); define
1268 CONFIG_USB_UHCI to enable it.
1269 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
1270 and define CONFIG_USB_STORAGE to enable the USB
1273 Supported are USB Keyboards and USB Floppy drives
1275 MPC5200 USB requires additional defines:
1277 for 528 MHz Clock: 0x0001bbbb
1281 for differential drivers: 0x00001000
1282 for single ended drivers: 0x00005000
1283 for differential drivers on PSC3: 0x00000100
1284 for single ended drivers on PSC3: 0x00004100
1285 CONFIG_SYS_USB_EVENT_POLL
1286 May be defined to allow interrupt polling
1287 instead of using asynchronous interrupts
1289 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the
1290 txfilltuning field in the EHCI controller on reset.
1292 CONFIG_USB_HUB_MIN_POWER_ON_DELAY defines the minimum
1293 interval for usb hub power-on delay.(minimum 100msec)
1296 Define the below if you wish to use the USB console.
1297 Once firmware is rebuilt from a serial console issue the
1298 command "setenv stdin usbtty; setenv stdout usbtty" and
1299 attach your USB cable. The Unix command "dmesg" should print
1300 it has found a new device. The environment variable usbtty
1301 can be set to gserial or cdc_acm to enable your device to
1302 appear to a USB host as a Linux gserial device or a
1303 Common Device Class Abstract Control Model serial device.
1304 If you select usbtty = gserial you should be able to enumerate
1306 # modprobe usbserial vendor=0xVendorID product=0xProductID
1307 else if using cdc_acm, simply setting the environment
1308 variable usbtty to be cdc_acm should suffice. The following
1309 might be defined in YourBoardName.h
1312 Define this to build a UDC device
1315 Define this to have a tty type of device available to
1316 talk to the UDC device
1319 Define this to enable the high speed support for usb
1320 device and usbtty. If this feature is enabled, a routine
1321 int is_usbd_high_speed(void)
1322 also needs to be defined by the driver to dynamically poll
1323 whether the enumeration has succeded at high speed or full
1326 CONFIG_SYS_CONSOLE_IS_IN_ENV
1327 Define this if you want stdin, stdout &/or stderr to
1331 CONFIG_SYS_USB_EXTC_CLK 0xBLAH
1332 Derive USB clock from external clock "blah"
1333 - CONFIG_SYS_USB_EXTC_CLK 0x02
1335 CONFIG_SYS_USB_BRG_CLK 0xBLAH
1336 Derive USB clock from brgclk
1337 - CONFIG_SYS_USB_BRG_CLK 0x04
1339 If you have a USB-IF assigned VendorID then you may wish to
1340 define your own vendor specific values either in BoardName.h
1341 or directly in usbd_vendor_info.h. If you don't define
1342 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
1343 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
1344 should pretend to be a Linux device to it's target host.
1346 CONFIG_USBD_MANUFACTURER
1347 Define this string as the name of your company for
1348 - CONFIG_USBD_MANUFACTURER "my company"
1350 CONFIG_USBD_PRODUCT_NAME
1351 Define this string as the name of your product
1352 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
1354 CONFIG_USBD_VENDORID
1355 Define this as your assigned Vendor ID from the USB
1356 Implementors Forum. This *must* be a genuine Vendor ID
1357 to avoid polluting the USB namespace.
1358 - CONFIG_USBD_VENDORID 0xFFFF
1360 CONFIG_USBD_PRODUCTID
1361 Define this as the unique Product ID
1363 - CONFIG_USBD_PRODUCTID 0xFFFF
1365 - ULPI Layer Support:
1366 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via
1367 the generic ULPI layer. The generic layer accesses the ULPI PHY
1368 via the platform viewport, so you need both the genric layer and
1369 the viewport enabled. Currently only Chipidea/ARC based
1370 viewport is supported.
1371 To enable the ULPI layer support, define CONFIG_USB_ULPI and
1372 CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
1373 If your ULPI phy needs a different reference clock than the
1374 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to
1375 the appropriate value in Hz.
1378 The MMC controller on the Intel PXA is supported. To
1379 enable this define CONFIG_MMC. The MMC can be
1380 accessed from the boot prompt by mapping the device
1381 to physical memory similar to flash. Command line is
1382 enabled with CONFIG_CMD_MMC. The MMC driver also works with
1383 the FAT fs. This is enabled with CONFIG_CMD_FAT.
1386 Support for Renesas on-chip MMCIF controller
1388 CONFIG_SH_MMCIF_ADDR
1389 Define the base address of MMCIF registers
1392 Define the clock frequency for MMCIF
1394 - USB Device Firmware Update (DFU) class support:
1396 This enables the USB portion of the DFU USB class
1399 This enables the command "dfu" which is used to have
1400 U-Boot create a DFU class device via USB. This command
1401 requires that the "dfu_alt_info" environment variable be
1402 set and define the alt settings to expose to the host.
1405 This enables support for exposing (e)MMC devices via DFU.
1408 This enables support for exposing NAND devices via DFU.
1411 This enables support for exposing RAM via DFU.
1412 Note: DFU spec refer to non-volatile memory usage, but
1413 allow usages beyond the scope of spec - here RAM usage,
1414 one that would help mostly the developer.
1416 CONFIG_SYS_DFU_DATA_BUF_SIZE
1417 Dfu transfer uses a buffer before writing data to the
1418 raw storage device. Make the size (in bytes) of this buffer
1419 configurable. The size of this buffer is also configurable
1420 through the "dfu_bufsiz" environment variable.
1422 CONFIG_SYS_DFU_MAX_FILE_SIZE
1423 When updating files rather than the raw storage device,
1424 we use a static buffer to copy the file into and then write
1425 the buffer once we've been given the whole file. Define
1426 this to the maximum filesize (in bytes) for the buffer.
1427 Default is 4 MiB if undefined.
1429 - Journaling Flash filesystem support:
1430 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
1431 CONFIG_JFFS2_NAND_DEV
1432 Define these for a default partition on a NAND device
1434 CONFIG_SYS_JFFS2_FIRST_SECTOR,
1435 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
1436 Define these for a default partition on a NOR device
1438 CONFIG_SYS_JFFS_CUSTOM_PART
1439 Define this to create an own partition. You have to provide a
1440 function struct part_info* jffs2_part_info(int part_num)
1442 If you define only one JFFS2 partition you may also want to
1443 #define CONFIG_SYS_JFFS_SINGLE_PART 1
1444 to disable the command chpart. This is the default when you
1445 have not defined a custom partition
1447 - FAT(File Allocation Table) filesystem write function support:
1450 Define this to enable support for saving memory data as a
1451 file in FAT formatted partition.
1453 This will also enable the command "fatwrite" enabling the
1454 user to write files to FAT.
1456 CBFS (Coreboot Filesystem) support
1459 Define this to enable support for reading from a Coreboot
1460 filesystem. Available commands are cbfsinit, cbfsinfo, cbfsls
1466 Define this to enable standard (PC-Style) keyboard
1470 Standard PC keyboard driver with US (is default) and
1471 GERMAN key layout (switch via environment 'keymap=de') support.
1472 Export function i8042_kbd_init, i8042_tstc and i8042_getc
1473 for cfb_console. Supports cursor blinking.
1476 Enables a Chrome OS keyboard using the CROS_EC interface.
1477 This uses CROS_EC to communicate with a second microcontroller
1478 which provides key scans on request.
1483 Define this to enable video support (for output to
1486 CONFIG_VIDEO_CT69000
1488 Enable Chips & Technologies 69000 Video chip
1490 CONFIG_VIDEO_SMI_LYNXEM
1491 Enable Silicon Motion SMI 712/710/810 Video chip. The
1492 video output is selected via environment 'videoout'
1493 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
1496 For the CT69000 and SMI_LYNXEM drivers, videomode is
1497 selected via environment 'videomode'. Two different ways
1499 - "videomode=num" 'num' is a standard LiLo mode numbers.
1500 Following standard modes are supported (* is default):
1502 Colors 640x480 800x600 1024x768 1152x864 1280x1024
1503 -------------+---------------------------------------------
1504 8 bits | 0x301* 0x303 0x305 0x161 0x307
1505 15 bits | 0x310 0x313 0x316 0x162 0x319
1506 16 bits | 0x311 0x314 0x317 0x163 0x31A
1507 24 bits | 0x312 0x315 0x318 ? 0x31B
1508 -------------+---------------------------------------------
1509 (i.e. setenv videomode 317; saveenv; reset;)
1511 - "videomode=bootargs" all the video parameters are parsed
1512 from the bootargs. (See drivers/video/videomodes.c)
1515 CONFIG_VIDEO_SED13806
1516 Enable Epson SED13806 driver. This driver supports 8bpp
1517 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
1518 or CONFIG_VIDEO_SED13806_16BPP
1521 Enable the Freescale DIU video driver. Reference boards for
1522 SOCs that have a DIU should define this macro to enable DIU
1523 support, and should also define these other macros:
1529 CONFIG_VIDEO_SW_CURSOR
1530 CONFIG_VGA_AS_SINGLE_DEVICE
1532 CONFIG_VIDEO_BMP_LOGO
1534 The DIU driver will look for the 'video-mode' environment
1535 variable, and if defined, enable the DIU as a console during
1536 boot. See the documentation file README.video for a
1537 description of this variable.
1541 Enable the VGA video / BIOS for x86. The alternative if you
1542 are using coreboot is to use the coreboot frame buffer
1549 Define this to enable a custom keyboard support.
1550 This simply calls drv_keyboard_init() which must be
1551 defined in your board-specific files.
1552 The only board using this so far is RBC823.
1554 - LCD Support: CONFIG_LCD
1556 Define this to enable LCD support (for output to LCD
1557 display); also select one of the supported displays
1558 by defining one of these:
1562 HITACHI TX09D70VM1CCA, 3.5", 240x320.
1564 CONFIG_NEC_NL6448AC33:
1566 NEC NL6448AC33-18. Active, color, single scan.
1568 CONFIG_NEC_NL6448BC20
1570 NEC NL6448BC20-08. 6.5", 640x480.
1571 Active, color, single scan.
1573 CONFIG_NEC_NL6448BC33_54
1575 NEC NL6448BC33-54. 10.4", 640x480.
1576 Active, color, single scan.
1580 Sharp 320x240. Active, color, single scan.
1581 It isn't 16x9, and I am not sure what it is.
1583 CONFIG_SHARP_LQ64D341
1585 Sharp LQ64D341 display, 640x480.
1586 Active, color, single scan.
1590 HLD1045 display, 640x480.
1591 Active, color, single scan.
1595 Optrex CBL50840-2 NF-FW 99 22 M5
1597 Hitachi LMG6912RPFC-00T
1601 320x240. Black & white.
1603 Normally display is black on white background; define
1604 CONFIG_SYS_WHITE_ON_BLACK to get it inverted.
1606 CONFIG_LCD_ALIGNMENT
1608 Normally the LCD is page-aligned (tyically 4KB). If this is
1609 defined then the LCD will be aligned to this value instead.
1610 For ARM it is sometimes useful to use MMU_SECTION_SIZE
1611 here, since it is cheaper to change data cache settings on
1612 a per-section basis.
1614 CONFIG_CONSOLE_SCROLL_LINES
1616 When the console need to be scrolled, this is the number of
1617 lines to scroll by. It defaults to 1. Increasing this makes
1618 the console jump but can help speed up operation when scrolling
1623 Support drawing of RLE8-compressed bitmaps on the LCD.
1627 Enables an 'i2c edid' command which can read EDID
1628 information over I2C from an attached LCD display.
1630 - Splash Screen Support: CONFIG_SPLASH_SCREEN
1632 If this option is set, the environment is checked for
1633 a variable "splashimage". If found, the usual display
1634 of logo, copyright and system information on the LCD
1635 is suppressed and the BMP image at the address
1636 specified in "splashimage" is loaded instead. The
1637 console is redirected to the "nulldev", too. This
1638 allows for a "silent" boot where a splash screen is
1639 loaded very quickly after power-on.
1641 CONFIG_SPLASHIMAGE_GUARD
1643 If this option is set, then U-Boot will prevent the environment
1644 variable "splashimage" from being set to a problematic address
1645 (see README.displaying-bmps and README.arm-unaligned-accesses).
1646 This option is useful for targets where, due to alignment
1647 restrictions, an improperly aligned BMP image will cause a data
1648 abort. If you think you will not have problems with unaligned
1649 accesses (for example because your toolchain prevents them)
1650 there is no need to set this option.
1652 CONFIG_SPLASH_SCREEN_ALIGN
1654 If this option is set the splash image can be freely positioned
1655 on the screen. Environment variable "splashpos" specifies the
1656 position as "x,y". If a positive number is given it is used as
1657 number of pixel from left/top. If a negative number is given it
1658 is used as number of pixel from right/bottom. You can also
1659 specify 'm' for centering the image.
1662 setenv splashpos m,m
1663 => image at center of screen
1665 setenv splashpos 30,20
1666 => image at x = 30 and y = 20
1668 setenv splashpos -10,m
1669 => vertically centered image
1670 at x = dspWidth - bmpWidth - 9
1672 - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
1674 If this option is set, additionally to standard BMP
1675 images, gzipped BMP images can be displayed via the
1676 splashscreen support or the bmp command.
1678 - Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
1680 If this option is set, 8-bit RLE compressed BMP images
1681 can be displayed via the splashscreen support or the
1684 - Do compresssing for memory range:
1687 If this option is set, it would use zlib deflate method
1688 to compress the specified memory at its best effort.
1690 - Compression support:
1693 Enabled by default to support gzip compressed images.
1697 If this option is set, support for bzip2 compressed
1698 images is included. If not, only uncompressed and gzip
1699 compressed images are supported.
1701 NOTE: the bzip2 algorithm requires a lot of RAM, so
1702 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
1707 If this option is set, support for lzma compressed
1710 Note: The LZMA algorithm adds between 2 and 4KB of code and it
1711 requires an amount of dynamic memory that is given by the
1714 (1846 + 768 << (lc + lp)) * sizeof(uint16)
1716 Where lc and lp stand for, respectively, Literal context bits
1717 and Literal pos bits.
1719 This value is upper-bounded by 14MB in the worst case. Anyway,
1720 for a ~4MB large kernel image, we have lc=3 and lp=0 for a
1721 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is
1722 a very small buffer.
1724 Use the lzmainfo tool to determinate the lc and lp values and
1725 then calculate the amount of needed dynamic memory (ensuring
1726 the appropriate CONFIG_SYS_MALLOC_LEN value).
1730 If this option is set, support for LZO compressed images
1736 The address of PHY on MII bus.
1738 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1740 The clock frequency of the MII bus
1744 If this option is set, support for speed/duplex
1745 detection of gigabit PHY is included.
1747 CONFIG_PHY_RESET_DELAY
1749 Some PHY like Intel LXT971A need extra delay after
1750 reset before any MII register access is possible.
1751 For such PHY, set this option to the usec delay
1752 required. (minimum 300usec for LXT971A)
1754 CONFIG_PHY_CMD_DELAY (ppc4xx)
1756 Some PHY like Intel LXT971A need extra delay after
1757 command issued before MII status register can be read
1767 Define a default value for Ethernet address to use
1768 for the respective Ethernet interface, in case this
1769 is not determined automatically.
1774 Define a default value for the IP address to use for
1775 the default Ethernet interface, in case this is not
1776 determined through e.g. bootp.
1777 (Environment variable "ipaddr")
1779 - Server IP address:
1782 Defines a default value for the IP address of a TFTP
1783 server to contact when using the "tftboot" command.
1784 (Environment variable "serverip")
1786 CONFIG_KEEP_SERVERADDR
1788 Keeps the server's MAC address, in the env 'serveraddr'
1789 for passing to bootargs (like Linux's netconsole option)
1791 - Gateway IP address:
1794 Defines a default value for the IP address of the
1795 default router where packets to other networks are
1797 (Environment variable "gatewayip")
1802 Defines a default value for the subnet mask (or
1803 routing prefix) which is used to determine if an IP
1804 address belongs to the local subnet or needs to be
1805 forwarded through a router.
1806 (Environment variable "netmask")
1808 - Multicast TFTP Mode:
1811 Defines whether you want to support multicast TFTP as per
1812 rfc-2090; for example to work with atftp. Lets lots of targets
1813 tftp down the same boot image concurrently. Note: the Ethernet
1814 driver in use must provide a function: mcast() to join/leave a
1817 - BOOTP Recovery Mode:
1818 CONFIG_BOOTP_RANDOM_DELAY
1820 If you have many targets in a network that try to
1821 boot using BOOTP, you may want to avoid that all
1822 systems send out BOOTP requests at precisely the same
1823 moment (which would happen for instance at recovery
1824 from a power failure, when all systems will try to
1825 boot, thus flooding the BOOTP server. Defining
1826 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1827 inserted before sending out BOOTP requests. The
1828 following delays are inserted then:
1830 1st BOOTP request: delay 0 ... 1 sec
1831 2nd BOOTP request: delay 0 ... 2 sec
1832 3rd BOOTP request: delay 0 ... 4 sec
1834 BOOTP requests: delay 0 ... 8 sec
1836 - DHCP Advanced Options:
1837 You can fine tune the DHCP functionality by defining
1838 CONFIG_BOOTP_* symbols:
1840 CONFIG_BOOTP_SUBNETMASK
1841 CONFIG_BOOTP_GATEWAY
1842 CONFIG_BOOTP_HOSTNAME
1843 CONFIG_BOOTP_NISDOMAIN
1844 CONFIG_BOOTP_BOOTPATH
1845 CONFIG_BOOTP_BOOTFILESIZE
1848 CONFIG_BOOTP_SEND_HOSTNAME
1849 CONFIG_BOOTP_NTPSERVER
1850 CONFIG_BOOTP_TIMEOFFSET
1851 CONFIG_BOOTP_VENDOREX
1852 CONFIG_BOOTP_MAY_FAIL
1854 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
1855 environment variable, not the BOOTP server.
1857 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found
1858 after the configured retry count, the call will fail
1859 instead of starting over. This can be used to fail over
1860 to Link-local IP address configuration if the DHCP server
1863 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
1864 serverip from a DHCP server, it is possible that more
1865 than one DNS serverip is offered to the client.
1866 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1867 serverip will be stored in the additional environment
1868 variable "dnsip2". The first DNS serverip is always
1869 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
1872 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1873 to do a dynamic update of a DNS server. To do this, they
1874 need the hostname of the DHCP requester.
1875 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
1876 of the "hostname" environment variable is passed as
1877 option 12 to the DHCP server.
1879 CONFIG_BOOTP_DHCP_REQUEST_DELAY
1881 A 32bit value in microseconds for a delay between
1882 receiving a "DHCP Offer" and sending the "DHCP Request".
1883 This fixes a problem with certain DHCP servers that don't
1884 respond 100% of the time to a "DHCP request". E.g. On an
1885 AT91RM9200 processor running at 180MHz, this delay needed
1886 to be *at least* 15,000 usec before a Windows Server 2003
1887 DHCP server would reply 100% of the time. I recommend at
1888 least 50,000 usec to be safe. The alternative is to hope
1889 that one of the retries will be successful but note that
1890 the DHCP timeout and retry process takes a longer than
1893 - Link-local IP address negotiation:
1894 Negotiate with other link-local clients on the local network
1895 for an address that doesn't require explicit configuration.
1896 This is especially useful if a DHCP server cannot be guaranteed
1897 to exist in all environments that the device must operate.
1899 See doc/README.link-local for more information.
1902 CONFIG_CDP_DEVICE_ID
1904 The device id used in CDP trigger frames.
1906 CONFIG_CDP_DEVICE_ID_PREFIX
1908 A two character string which is prefixed to the MAC address
1913 A printf format string which contains the ascii name of
1914 the port. Normally is set to "eth%d" which sets
1915 eth0 for the first Ethernet, eth1 for the second etc.
1917 CONFIG_CDP_CAPABILITIES
1919 A 32bit integer which indicates the device capabilities;
1920 0x00000010 for a normal host which does not forwards.
1924 An ascii string containing the version of the software.
1928 An ascii string containing the name of the platform.
1932 A 32bit integer sent on the trigger.
1934 CONFIG_CDP_POWER_CONSUMPTION
1936 A 16bit integer containing the power consumption of the
1937 device in .1 of milliwatts.
1939 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1941 A byte containing the id of the VLAN.
1943 - Status LED: CONFIG_STATUS_LED
1945 Several configurations allow to display the current
1946 status using a LED. For instance, the LED will blink
1947 fast while running U-Boot code, stop blinking as
1948 soon as a reply to a BOOTP request was received, and
1949 start blinking slow once the Linux kernel is running
1950 (supported by a status LED driver in the Linux
1951 kernel). Defining CONFIG_STATUS_LED enables this
1954 - CAN Support: CONFIG_CAN_DRIVER
1956 Defining CONFIG_CAN_DRIVER enables CAN driver support
1957 on those systems that support this (optional)
1958 feature, like the TQM8xxL modules.
1960 - I2C Support: CONFIG_SYS_I2C
1962 This enable the NEW i2c subsystem, and will allow you to use
1963 i2c commands at the u-boot command line (as long as you set
1964 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c
1965 based realtime clock chips or other i2c devices. See
1966 common/cmd_i2c.c for a description of the command line
1969 ported i2c driver to the new framework:
1970 - drivers/i2c/soft_i2c.c:
1971 - activate first bus with CONFIG_SYS_I2C_SOFT define
1972 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE
1973 for defining speed and slave address
1974 - activate second bus with I2C_SOFT_DECLARATIONS2 define
1975 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2
1976 for defining speed and slave address
1977 - activate third bus with I2C_SOFT_DECLARATIONS3 define
1978 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3
1979 for defining speed and slave address
1980 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define
1981 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4
1982 for defining speed and slave address
1984 - drivers/i2c/fsl_i2c.c:
1985 - activate i2c driver with CONFIG_SYS_I2C_FSL
1986 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register
1987 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and
1988 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first
1990 - If your board supports a second fsl i2c bus, define
1991 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset
1992 CONFIG_SYS_FSL_I2C2_SPEED for the speed and
1993 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the
1996 - drivers/i2c/tegra_i2c.c:
1997 - activate this driver with CONFIG_SYS_I2C_TEGRA
1998 - This driver adds 4 i2c buses with a fix speed from
1999 100000 and the slave addr 0!
2001 - drivers/i2c/ppc4xx_i2c.c
2002 - activate this driver with CONFIG_SYS_I2C_PPC4XX
2003 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0
2004 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1
2006 - drivers/i2c/i2c_mxc.c
2007 - activate this driver with CONFIG_SYS_I2C_MXC
2008 - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED
2009 - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE
2010 - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED
2011 - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE
2012 - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED
2013 - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE
2014 If thoses defines are not set, default value is 100000
2015 for speed, and 0 for slave.
2019 CONFIG_SYS_NUM_I2C_BUSES
2020 Hold the number of i2c busses you want to use. If you
2021 don't use/have i2c muxes on your i2c bus, this
2022 is equal to CONFIG_SYS_NUM_I2C_ADAPTERS, and you can
2025 CONFIG_SYS_I2C_DIRECT_BUS
2026 define this, if you don't use i2c muxes on your hardware.
2027 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can
2030 CONFIG_SYS_I2C_MAX_HOPS
2031 define how many muxes are maximal consecutively connected
2032 on one i2c bus. If you not use i2c muxes, omit this
2035 CONFIG_SYS_I2C_BUSES
2036 hold a list of busses you want to use, only used if
2037 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example
2038 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and
2039 CONFIG_SYS_NUM_I2C_BUSES = 9:
2041 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \
2042 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \
2043 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \
2044 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \
2045 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \
2046 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \
2047 {1, {I2C_NULL_HOP}}, \
2048 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \
2049 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \
2053 bus 0 on adapter 0 without a mux
2054 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1
2055 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2
2056 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3
2057 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4
2058 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5
2059 bus 6 on adapter 1 without a mux
2060 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1
2061 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2
2063 If you do not have i2c muxes on your board, omit this define.
2065 - Legacy I2C Support: CONFIG_HARD_I2C
2067 NOTE: It is intended to move drivers to CONFIG_SYS_I2C which
2068 provides the following compelling advantages:
2070 - more than one i2c adapter is usable
2071 - approved multibus support
2072 - better i2c mux support
2074 ** Please consider updating your I2C driver now. **
2076 These enable legacy I2C serial bus commands. Defining
2077 CONFIG_HARD_I2C will include the appropriate I2C driver
2078 for the selected CPU.
2080 This will allow you to use i2c commands at the u-boot
2081 command line (as long as you set CONFIG_CMD_I2C in
2082 CONFIG_COMMANDS) and communicate with i2c based realtime
2083 clock chips. See common/cmd_i2c.c for a description of the
2084 command line interface.
2086 CONFIG_HARD_I2C selects a hardware I2C controller.
2088 There are several other quantities that must also be
2089 defined when you define CONFIG_HARD_I2C.
2091 In both cases you will need to define CONFIG_SYS_I2C_SPEED
2092 to be the frequency (in Hz) at which you wish your i2c bus
2093 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie
2094 the CPU's i2c node address).
2096 Now, the u-boot i2c code for the mpc8xx
2097 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node
2098 and so its address should therefore be cleared to 0 (See,
2099 eg, MPC823e User's Manual p.16-473). So, set
2100 CONFIG_SYS_I2C_SLAVE to 0.
2102 CONFIG_SYS_I2C_INIT_MPC5XXX
2104 When a board is reset during an i2c bus transfer
2105 chips might think that the current transfer is still
2106 in progress. Reset the slave devices by sending start
2107 commands until the slave device responds.
2109 That's all that's required for CONFIG_HARD_I2C.
2111 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT)
2112 then the following macros need to be defined (examples are
2113 from include/configs/lwmon.h):
2117 (Optional). Any commands necessary to enable the I2C
2118 controller or configure ports.
2120 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
2124 (Only for MPC8260 CPU). The I/O port to use (the code
2125 assumes both bits are on the same port). Valid values
2126 are 0..3 for ports A..D.
2130 The code necessary to make the I2C data line active
2131 (driven). If the data line is open collector, this
2134 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
2138 The code necessary to make the I2C data line tri-stated
2139 (inactive). If the data line is open collector, this
2142 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
2146 Code that returns true if the I2C data line is high,
2149 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
2153 If <bit> is true, sets the I2C data line high. If it
2154 is false, it clears it (low).
2156 eg: #define I2C_SDA(bit) \
2157 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
2158 else immr->im_cpm.cp_pbdat &= ~PB_SDA
2162 If <bit> is true, sets the I2C clock line high. If it
2163 is false, it clears it (low).
2165 eg: #define I2C_SCL(bit) \
2166 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
2167 else immr->im_cpm.cp_pbdat &= ~PB_SCL
2171 This delay is invoked four times per clock cycle so this
2172 controls the rate of data transfer. The data rate thus
2173 is 1 / (I2C_DELAY * 4). Often defined to be something
2176 #define I2C_DELAY udelay(2)
2178 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
2180 If your arch supports the generic GPIO framework (asm/gpio.h),
2181 then you may alternatively define the two GPIOs that are to be
2182 used as SCL / SDA. Any of the previous I2C_xxx macros will
2183 have GPIO-based defaults assigned to them as appropriate.
2185 You should define these to the GPIO value as given directly to
2186 the generic GPIO functions.
2188 CONFIG_SYS_I2C_INIT_BOARD
2190 When a board is reset during an i2c bus transfer
2191 chips might think that the current transfer is still
2192 in progress. On some boards it is possible to access
2193 the i2c SCLK line directly, either by using the
2194 processor pin as a GPIO or by having a second pin
2195 connected to the bus. If this option is defined a
2196 custom i2c_init_board() routine in boards/xxx/board.c
2197 is run early in the boot sequence.
2199 CONFIG_SYS_I2C_BOARD_LATE_INIT
2201 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is
2202 defined a custom i2c_board_late_init() routine in
2203 boards/xxx/board.c is run AFTER the operations in i2c_init()
2204 is completed. This callpoint can be used to unreset i2c bus
2205 using CPU i2c controller register accesses for CPUs whose i2c
2206 controller provide such a method. It is called at the end of
2207 i2c_init() to allow i2c_init operations to setup the i2c bus
2208 controller on the CPU (e.g. setting bus speed & slave address).
2210 CONFIG_I2CFAST (PPC405GP|PPC405EP only)
2212 This option enables configuration of bi_iic_fast[] flags
2213 in u-boot bd_info structure based on u-boot environment
2214 variable "i2cfast". (see also i2cfast)
2216 CONFIG_I2C_MULTI_BUS
2218 This option allows the use of multiple I2C buses, each of which
2219 must have a controller. At any point in time, only one bus is
2220 active. To switch to a different bus, use the 'i2c dev' command.
2221 Note that bus numbering is zero-based.
2223 CONFIG_SYS_I2C_NOPROBES
2225 This option specifies a list of I2C devices that will be skipped
2226 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
2227 is set, specify a list of bus-device pairs. Otherwise, specify
2228 a 1D array of device addresses
2231 #undef CONFIG_I2C_MULTI_BUS
2232 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
2234 will skip addresses 0x50 and 0x68 on a board with one I2C bus
2236 #define CONFIG_I2C_MULTI_BUS
2237 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
2239 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
2241 CONFIG_SYS_SPD_BUS_NUM
2243 If defined, then this indicates the I2C bus number for DDR SPD.
2244 If not defined, then U-Boot assumes that SPD is on I2C bus 0.
2246 CONFIG_SYS_RTC_BUS_NUM
2248 If defined, then this indicates the I2C bus number for the RTC.
2249 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
2251 CONFIG_SYS_DTT_BUS_NUM
2253 If defined, then this indicates the I2C bus number for the DTT.
2254 If not defined, then U-Boot assumes that DTT is on I2C bus 0.
2256 CONFIG_SYS_I2C_DTT_ADDR:
2258 If defined, specifies the I2C address of the DTT device.
2259 If not defined, then U-Boot uses predefined value for
2260 specified DTT device.
2262 CONFIG_SOFT_I2C_READ_REPEATED_START
2264 defining this will force the i2c_read() function in
2265 the soft_i2c driver to perform an I2C repeated start
2266 between writing the address pointer and reading the
2267 data. If this define is omitted the default behaviour
2268 of doing a stop-start sequence will be used. Most I2C
2269 devices can use either method, but some require one or
2272 - SPI Support: CONFIG_SPI
2274 Enables SPI driver (so far only tested with
2275 SPI EEPROM, also an instance works with Crystal A/D and
2276 D/As on the SACSng board)
2280 Enables the driver for SPI controller on SuperH. Currently
2281 only SH7757 is supported.
2285 Enables extended (16-bit) SPI EEPROM addressing.
2286 (symmetrical to CONFIG_I2C_X)
2290 Enables a software (bit-bang) SPI driver rather than
2291 using hardware support. This is a general purpose
2292 driver that only requires three general I/O port pins
2293 (two outputs, one input) to function. If this is
2294 defined, the board configuration must define several
2295 SPI configuration items (port pins to use, etc). For
2296 an example, see include/configs/sacsng.h.
2300 Enables a hardware SPI driver for general-purpose reads
2301 and writes. As with CONFIG_SOFT_SPI, the board configuration
2302 must define a list of chip-select function pointers.
2303 Currently supported on some MPC8xxx processors. For an
2304 example, see include/configs/mpc8349emds.h.
2308 Enables the driver for the SPI controllers on i.MX and MXC
2309 SoCs. Currently i.MX31/35/51 are supported.
2311 - FPGA Support: CONFIG_FPGA
2313 Enables FPGA subsystem.
2315 CONFIG_FPGA_<vendor>
2317 Enables support for specific chip vendors.
2320 CONFIG_FPGA_<family>
2322 Enables support for FPGA family.
2323 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
2327 Specify the number of FPGA devices to support.
2329 CONFIG_SYS_FPGA_PROG_FEEDBACK
2331 Enable printing of hash marks during FPGA configuration.
2333 CONFIG_SYS_FPGA_CHECK_BUSY
2335 Enable checks on FPGA configuration interface busy
2336 status by the configuration function. This option
2337 will require a board or device specific function to
2342 If defined, a function that provides delays in the FPGA
2343 configuration driver.
2345 CONFIG_SYS_FPGA_CHECK_CTRLC
2346 Allow Control-C to interrupt FPGA configuration
2348 CONFIG_SYS_FPGA_CHECK_ERROR
2350 Check for configuration errors during FPGA bitfile
2351 loading. For example, abort during Virtex II
2352 configuration if the INIT_B line goes low (which
2353 indicated a CRC error).
2355 CONFIG_SYS_FPGA_WAIT_INIT
2357 Maximum time to wait for the INIT_B line to deassert
2358 after PROB_B has been deasserted during a Virtex II
2359 FPGA configuration sequence. The default time is 500
2362 CONFIG_SYS_FPGA_WAIT_BUSY
2364 Maximum time to wait for BUSY to deassert during
2365 Virtex II FPGA configuration. The default is 5 ms.
2367 CONFIG_SYS_FPGA_WAIT_CONFIG
2369 Time to wait after FPGA configuration. The default is
2372 - Configuration Management:
2375 If defined, this string will be added to the U-Boot
2376 version information (U_BOOT_VERSION)
2378 - Vendor Parameter Protection:
2380 U-Boot considers the values of the environment
2381 variables "serial#" (Board Serial Number) and
2382 "ethaddr" (Ethernet Address) to be parameters that
2383 are set once by the board vendor / manufacturer, and
2384 protects these variables from casual modification by
2385 the user. Once set, these variables are read-only,
2386 and write or delete attempts are rejected. You can
2387 change this behaviour:
2389 If CONFIG_ENV_OVERWRITE is #defined in your config
2390 file, the write protection for vendor parameters is
2391 completely disabled. Anybody can change or delete
2394 Alternatively, if you #define _both_ CONFIG_ETHADDR
2395 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
2396 Ethernet address is installed in the environment,
2397 which can be changed exactly ONCE by the user. [The
2398 serial# is unaffected by this, i. e. it remains
2401 The same can be accomplished in a more flexible way
2402 for any variable by configuring the type of access
2403 to allow for those variables in the ".flags" variable
2404 or define CONFIG_ENV_FLAGS_LIST_STATIC.
2409 Define this variable to enable the reservation of
2410 "protected RAM", i. e. RAM which is not overwritten
2411 by U-Boot. Define CONFIG_PRAM to hold the number of
2412 kB you want to reserve for pRAM. You can overwrite
2413 this default value by defining an environment
2414 variable "pram" to the number of kB you want to
2415 reserve. Note that the board info structure will
2416 still show the full amount of RAM. If pRAM is
2417 reserved, a new environment variable "mem" will
2418 automatically be defined to hold the amount of
2419 remaining RAM in a form that can be passed as boot
2420 argument to Linux, for instance like that:
2422 setenv bootargs ... mem=\${mem}
2425 This way you can tell Linux not to use this memory,
2426 either, which results in a memory region that will
2427 not be affected by reboots.
2429 *WARNING* If your board configuration uses automatic
2430 detection of the RAM size, you must make sure that
2431 this memory test is non-destructive. So far, the
2432 following board configurations are known to be
2435 IVMS8, IVML24, SPD8xx, TQM8xxL,
2436 HERMES, IP860, RPXlite, LWMON,
2439 - Access to physical memory region (> 4GB)
2440 Some basic support is provided for operations on memory not
2441 normally accessible to U-Boot - e.g. some architectures
2442 support access to more than 4GB of memory on 32-bit
2443 machines using physical address extension or similar.
2444 Define CONFIG_PHYSMEM to access this basic support, which
2445 currently only supports clearing the memory.
2450 Define this variable to stop the system in case of a
2451 fatal error, so that you have to reset it manually.
2452 This is probably NOT a good idea for an embedded
2453 system where you want the system to reboot
2454 automatically as fast as possible, but it may be
2455 useful during development since you can try to debug
2456 the conditions that lead to the situation.
2458 CONFIG_NET_RETRY_COUNT
2460 This variable defines the number of retries for
2461 network operations like ARP, RARP, TFTP, or BOOTP
2462 before giving up the operation. If not defined, a
2463 default value of 5 is used.
2467 Timeout waiting for an ARP reply in milliseconds.
2471 Timeout in milliseconds used in NFS protocol.
2472 If you encounter "ERROR: Cannot umount" in nfs command,
2473 try longer timeout such as
2474 #define CONFIG_NFS_TIMEOUT 10000UL
2476 - Command Interpreter:
2477 CONFIG_AUTO_COMPLETE
2479 Enable auto completion of commands using TAB.
2481 Note that this feature has NOT been implemented yet
2482 for the "hush" shell.
2485 CONFIG_SYS_HUSH_PARSER
2487 Define this variable to enable the "hush" shell (from
2488 Busybox) as command line interpreter, thus enabling
2489 powerful command line syntax like
2490 if...then...else...fi conditionals or `&&' and '||'
2491 constructs ("shell scripts").
2493 If undefined, you get the old, much simpler behaviour
2494 with a somewhat smaller memory footprint.
2497 CONFIG_SYS_PROMPT_HUSH_PS2
2499 This defines the secondary prompt string, which is
2500 printed when the command interpreter needs more input
2501 to complete a command. Usually "> ".
2505 In the current implementation, the local variables
2506 space and global environment variables space are
2507 separated. Local variables are those you define by
2508 simply typing `name=value'. To access a local
2509 variable later on, you have write `$name' or
2510 `${name}'; to execute the contents of a variable
2511 directly type `$name' at the command prompt.
2513 Global environment variables are those you use
2514 setenv/printenv to work with. To run a command stored
2515 in such a variable, you need to use the run command,
2516 and you must not use the '$' sign to access them.
2518 To store commands and special characters in a
2519 variable, please use double quotation marks
2520 surrounding the whole text of the variable, instead
2521 of the backslashes before semicolons and special
2524 - Commandline Editing and History:
2525 CONFIG_CMDLINE_EDITING
2527 Enable editing and History functions for interactive
2528 commandline input operations
2530 - Default Environment:
2531 CONFIG_EXTRA_ENV_SETTINGS
2533 Define this to contain any number of null terminated
2534 strings (variable = value pairs) that will be part of
2535 the default environment compiled into the boot image.
2537 For example, place something like this in your
2538 board's config file:
2540 #define CONFIG_EXTRA_ENV_SETTINGS \
2544 Warning: This method is based on knowledge about the
2545 internal format how the environment is stored by the
2546 U-Boot code. This is NOT an official, exported
2547 interface! Although it is unlikely that this format
2548 will change soon, there is no guarantee either.
2549 You better know what you are doing here.
2551 Note: overly (ab)use of the default environment is
2552 discouraged. Make sure to check other ways to preset
2553 the environment like the "source" command or the
2556 CONFIG_ENV_VARS_UBOOT_CONFIG
2558 Define this in order to add variables describing the
2559 U-Boot build configuration to the default environment.
2560 These will be named arch, cpu, board, vendor, and soc.
2562 Enabling this option will cause the following to be defined:
2570 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG
2572 Define this in order to add variables describing certain
2573 run-time determined information about the hardware to the
2574 environment. These will be named board_name, board_rev.
2576 CONFIG_DELAY_ENVIRONMENT
2578 Normally the environment is loaded when the board is
2579 intialised so that it is available to U-Boot. This inhibits
2580 that so that the environment is not available until
2581 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL
2582 this is instead controlled by the value of
2583 /config/load-environment.
2585 - DataFlash Support:
2586 CONFIG_HAS_DATAFLASH
2588 Defining this option enables DataFlash features and
2589 allows to read/write in Dataflash via the standard
2592 - Serial Flash support
2595 Defining this option enables SPI flash commands
2596 'sf probe/read/write/erase/update'.
2598 Usage requires an initial 'probe' to define the serial
2599 flash parameters, followed by read/write/erase/update
2602 The following defaults may be provided by the platform
2603 to handle the common case when only a single serial
2604 flash is present on the system.
2606 CONFIG_SF_DEFAULT_BUS Bus identifier
2607 CONFIG_SF_DEFAULT_CS Chip-select
2608 CONFIG_SF_DEFAULT_MODE (see include/spi.h)
2609 CONFIG_SF_DEFAULT_SPEED in Hz
2613 Define this option to include a destructive SPI flash
2616 CONFIG_SPI_FLASH_BAR Ban/Extended Addr Reg
2618 Define this option to use the Bank addr/Extended addr
2619 support on SPI flashes which has size > 16Mbytes.
2621 - SystemACE Support:
2624 Adding this option adds support for Xilinx SystemACE
2625 chips attached via some sort of local bus. The address
2626 of the chip must also be defined in the
2627 CONFIG_SYS_SYSTEMACE_BASE macro. For example:
2629 #define CONFIG_SYSTEMACE
2630 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000
2632 When SystemACE support is added, the "ace" device type
2633 becomes available to the fat commands, i.e. fatls.
2635 - TFTP Fixed UDP Port:
2638 If this is defined, the environment variable tftpsrcp
2639 is used to supply the TFTP UDP source port value.
2640 If tftpsrcp isn't defined, the normal pseudo-random port
2641 number generator is used.
2643 Also, the environment variable tftpdstp is used to supply
2644 the TFTP UDP destination port value. If tftpdstp isn't
2645 defined, the normal port 69 is used.
2647 The purpose for tftpsrcp is to allow a TFTP server to
2648 blindly start the TFTP transfer using the pre-configured
2649 target IP address and UDP port. This has the effect of
2650 "punching through" the (Windows XP) firewall, allowing
2651 the remainder of the TFTP transfer to proceed normally.
2652 A better solution is to properly configure the firewall,
2653 but sometimes that is not allowed.
2658 This enables a generic 'hash' command which can produce
2659 hashes / digests from a few algorithms (e.g. SHA1, SHA256).
2663 Enable the hash verify command (hash -v). This adds to code
2666 CONFIG_SHA1 - support SHA1 hashing
2667 CONFIG_SHA256 - support SHA256 hashing
2669 Note: There is also a sha1sum command, which should perhaps
2670 be deprecated in favour of 'hash sha1'.
2672 - Freescale i.MX specific commands:
2673 CONFIG_CMD_HDMIDETECT
2674 This enables 'hdmidet' command which returns true if an
2675 HDMI monitor is detected. This command is i.MX 6 specific.
2678 This enables the 'bmode' (bootmode) command for forcing
2679 a boot from specific media.
2681 This is useful for forcing the ROM's usb downloader to
2682 activate upon a watchdog reset which is nice when iterating
2683 on U-Boot. Using the reset button or running bmode normal
2684 will set it back to normal. This command currently
2685 supports i.MX53 and i.MX6.
2690 This enables the RSA algorithm used for FIT image verification
2691 in U-Boot. See doc/uImage/signature for more information.
2693 The signing part is build into mkimage regardless of this
2697 - Show boot progress:
2698 CONFIG_SHOW_BOOT_PROGRESS
2700 Defining this option allows to add some board-
2701 specific code (calling a user-provided function
2702 "show_boot_progress(int)") that enables you to show
2703 the system's boot progress on some display (for
2704 example, some LED's) on your board. At the moment,
2705 the following checkpoints are implemented:
2707 - Detailed boot stage timing
2709 Define this option to get detailed timing of each stage
2710 of the boot process.
2712 CONFIG_BOOTSTAGE_USER_COUNT
2713 This is the number of available user bootstage records.
2714 Each time you call bootstage_mark(BOOTSTAGE_ID_ALLOC, ...)
2715 a new ID will be allocated from this stash. If you exceed
2716 the limit, recording will stop.
2718 CONFIG_BOOTSTAGE_REPORT
2719 Define this to print a report before boot, similar to this:
2721 Timer summary in microseconds:
2724 3,575,678 3,575,678 board_init_f start
2725 3,575,695 17 arch_cpu_init A9
2726 3,575,777 82 arch_cpu_init done
2727 3,659,598 83,821 board_init_r start
2728 3,910,375 250,777 main_loop
2729 29,916,167 26,005,792 bootm_start
2730 30,361,327 445,160 start_kernel
2732 CONFIG_CMD_BOOTSTAGE
2733 Add a 'bootstage' command which supports printing a report
2734 and un/stashing of bootstage data.
2736 CONFIG_BOOTSTAGE_FDT
2737 Stash the bootstage information in the FDT. A root 'bootstage'
2738 node is created with each bootstage id as a child. Each child
2739 has a 'name' property and either 'mark' containing the
2740 mark time in microsecond, or 'accum' containing the
2741 accumulated time for that bootstage id in microseconds.
2746 name = "board_init_f";
2755 Code in the Linux kernel can find this in /proc/devicetree.
2757 Legacy uImage format:
2760 1 common/cmd_bootm.c before attempting to boot an image
2761 -1 common/cmd_bootm.c Image header has bad magic number
2762 2 common/cmd_bootm.c Image header has correct magic number
2763 -2 common/cmd_bootm.c Image header has bad checksum
2764 3 common/cmd_bootm.c Image header has correct checksum
2765 -3 common/cmd_bootm.c Image data has bad checksum
2766 4 common/cmd_bootm.c Image data has correct checksum
2767 -4 common/cmd_bootm.c Image is for unsupported architecture
2768 5 common/cmd_bootm.c Architecture check OK
2769 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
2770 6 common/cmd_bootm.c Image Type check OK
2771 -6 common/cmd_bootm.c gunzip uncompression error
2772 -7 common/cmd_bootm.c Unimplemented compression type
2773 7 common/cmd_bootm.c Uncompression OK
2774 8 common/cmd_bootm.c No uncompress/copy overwrite error
2775 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
2777 9 common/image.c Start initial ramdisk verification
2778 -10 common/image.c Ramdisk header has bad magic number
2779 -11 common/image.c Ramdisk header has bad checksum
2780 10 common/image.c Ramdisk header is OK
2781 -12 common/image.c Ramdisk data has bad checksum
2782 11 common/image.c Ramdisk data has correct checksum
2783 12 common/image.c Ramdisk verification complete, start loading
2784 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
2785 13 common/image.c Start multifile image verification
2786 14 common/image.c No initial ramdisk, no multifile, continue.
2788 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
2790 -30 arch/powerpc/lib/board.c Fatal error, hang the system
2791 -31 post/post.c POST test failed, detected by post_output_backlog()
2792 -32 post/post.c POST test failed, detected by post_run_single()
2794 34 common/cmd_doc.c before loading a Image from a DOC device
2795 -35 common/cmd_doc.c Bad usage of "doc" command
2796 35 common/cmd_doc.c correct usage of "doc" command
2797 -36 common/cmd_doc.c No boot device
2798 36 common/cmd_doc.c correct boot device
2799 -37 common/cmd_doc.c Unknown Chip ID on boot device
2800 37 common/cmd_doc.c correct chip ID found, device available
2801 -38 common/cmd_doc.c Read Error on boot device
2802 38 common/cmd_doc.c reading Image header from DOC device OK
2803 -39 common/cmd_doc.c Image header has bad magic number
2804 39 common/cmd_doc.c Image header has correct magic number
2805 -40 common/cmd_doc.c Error reading Image from DOC device
2806 40 common/cmd_doc.c Image header has correct magic number
2807 41 common/cmd_ide.c before loading a Image from a IDE device
2808 -42 common/cmd_ide.c Bad usage of "ide" command
2809 42 common/cmd_ide.c correct usage of "ide" command
2810 -43 common/cmd_ide.c No boot device
2811 43 common/cmd_ide.c boot device found
2812 -44 common/cmd_ide.c Device not available
2813 44 common/cmd_ide.c Device available
2814 -45 common/cmd_ide.c wrong partition selected
2815 45 common/cmd_ide.c partition selected
2816 -46 common/cmd_ide.c Unknown partition table
2817 46 common/cmd_ide.c valid partition table found
2818 -47 common/cmd_ide.c Invalid partition type
2819 47 common/cmd_ide.c correct partition type
2820 -48 common/cmd_ide.c Error reading Image Header on boot device
2821 48 common/cmd_ide.c reading Image Header from IDE device OK
2822 -49 common/cmd_ide.c Image header has bad magic number
2823 49 common/cmd_ide.c Image header has correct magic number
2824 -50 common/cmd_ide.c Image header has bad checksum
2825 50 common/cmd_ide.c Image header has correct checksum
2826 -51 common/cmd_ide.c Error reading Image from IDE device
2827 51 common/cmd_ide.c reading Image from IDE device OK
2828 52 common/cmd_nand.c before loading a Image from a NAND device
2829 -53 common/cmd_nand.c Bad usage of "nand" command
2830 53 common/cmd_nand.c correct usage of "nand" command
2831 -54 common/cmd_nand.c No boot device
2832 54 common/cmd_nand.c boot device found
2833 -55 common/cmd_nand.c Unknown Chip ID on boot device
2834 55 common/cmd_nand.c correct chip ID found, device available
2835 -56 common/cmd_nand.c Error reading Image Header on boot device
2836 56 common/cmd_nand.c reading Image Header from NAND device OK
2837 -57 common/cmd_nand.c Image header has bad magic number
2838 57 common/cmd_nand.c Image header has correct magic number
2839 -58 common/cmd_nand.c Error reading Image from NAND device
2840 58 common/cmd_nand.c reading Image from NAND device OK
2842 -60 common/env_common.c Environment has a bad CRC, using default
2844 64 net/eth.c starting with Ethernet configuration.
2845 -64 net/eth.c no Ethernet found.
2846 65 net/eth.c Ethernet found.
2848 -80 common/cmd_net.c usage wrong
2849 80 common/cmd_net.c before calling NetLoop()
2850 -81 common/cmd_net.c some error in NetLoop() occurred
2851 81 common/cmd_net.c NetLoop() back without error
2852 -82 common/cmd_net.c size == 0 (File with size 0 loaded)
2853 82 common/cmd_net.c trying automatic boot
2854 83 common/cmd_net.c running "source" command
2855 -83 common/cmd_net.c some error in automatic boot or "source" command
2856 84 common/cmd_net.c end without errors
2861 100 common/cmd_bootm.c Kernel FIT Image has correct format
2862 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
2863 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
2864 -101 common/cmd_bootm.c Can't get configuration for kernel subimage
2865 102 common/cmd_bootm.c Kernel unit name specified
2866 -103 common/cmd_bootm.c Can't get kernel subimage node offset
2867 103 common/cmd_bootm.c Found configuration node
2868 104 common/cmd_bootm.c Got kernel subimage node offset
2869 -104 common/cmd_bootm.c Kernel subimage hash verification failed
2870 105 common/cmd_bootm.c Kernel subimage hash verification OK
2871 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
2872 106 common/cmd_bootm.c Architecture check OK
2873 -106 common/cmd_bootm.c Kernel subimage has wrong type
2874 107 common/cmd_bootm.c Kernel subimage type OK
2875 -107 common/cmd_bootm.c Can't get kernel subimage data/size
2876 108 common/cmd_bootm.c Got kernel subimage data/size
2877 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
2878 -109 common/cmd_bootm.c Can't get kernel subimage type
2879 -110 common/cmd_bootm.c Can't get kernel subimage comp
2880 -111 common/cmd_bootm.c Can't get kernel subimage os
2881 -112 common/cmd_bootm.c Can't get kernel subimage load address
2882 -113 common/cmd_bootm.c Image uncompress/copy overwrite error
2884 120 common/image.c Start initial ramdisk verification
2885 -120 common/image.c Ramdisk FIT image has incorrect format
2886 121 common/image.c Ramdisk FIT image has correct format
2887 122 common/image.c No ramdisk subimage unit name, using configuration
2888 -122 common/image.c Can't get configuration for ramdisk subimage
2889 123 common/image.c Ramdisk unit name specified
2890 -124 common/image.c Can't get ramdisk subimage node offset
2891 125 common/image.c Got ramdisk subimage node offset
2892 -125 common/image.c Ramdisk subimage hash verification failed
2893 126 common/image.c Ramdisk subimage hash verification OK
2894 -126 common/image.c Ramdisk subimage for unsupported architecture
2895 127 common/image.c Architecture check OK
2896 -127 common/image.c Can't get ramdisk subimage data/size
2897 128 common/image.c Got ramdisk subimage data/size
2898 129 common/image.c Can't get ramdisk load address
2899 -129 common/image.c Got ramdisk load address
2901 -130 common/cmd_doc.c Incorrect FIT image format
2902 131 common/cmd_doc.c FIT image format OK
2904 -140 common/cmd_ide.c Incorrect FIT image format
2905 141 common/cmd_ide.c FIT image format OK
2907 -150 common/cmd_nand.c Incorrect FIT image format
2908 151 common/cmd_nand.c FIT image format OK
2910 - FIT image support:
2912 Enable support for the FIT uImage format.
2914 CONFIG_FIT_BEST_MATCH
2915 When no configuration is explicitly selected, default to the
2916 one whose fdt's compatibility field best matches that of
2917 U-Boot itself. A match is considered "best" if it matches the
2918 most specific compatibility entry of U-Boot's fdt's root node.
2919 The order of entries in the configuration's fdt is ignored.
2921 CONFIG_FIT_SIGNATURE
2922 This option enables signature verification of FIT uImages,
2923 using a hash signed and verified using RSA. See
2924 doc/uImage.FIT/signature.txt for more details.
2926 - Standalone program support:
2927 CONFIG_STANDALONE_LOAD_ADDR
2929 This option defines a board specific value for the
2930 address where standalone program gets loaded, thus
2931 overwriting the architecture dependent default
2934 - Frame Buffer Address:
2937 Define CONFIG_FB_ADDR if you want to use specific
2938 address for frame buffer. This is typically the case
2939 when using a graphics controller has separate video
2940 memory. U-Boot will then place the frame buffer at
2941 the given address instead of dynamically reserving it
2942 in system RAM by calling lcd_setmem(), which grabs
2943 the memory for the frame buffer depending on the
2944 configured panel size.
2946 Please see board_init_f function.
2948 - Automatic software updates via TFTP server
2950 CONFIG_UPDATE_TFTP_CNT_MAX
2951 CONFIG_UPDATE_TFTP_MSEC_MAX
2953 These options enable and control the auto-update feature;
2954 for a more detailed description refer to doc/README.update.
2956 - MTD Support (mtdparts command, UBI support)
2959 Adds the MTD device infrastructure from the Linux kernel.
2960 Needed for mtdparts command support.
2962 CONFIG_MTD_PARTITIONS
2964 Adds the MTD partitioning infrastructure from the Linux
2965 kernel. Needed for UBI support.
2970 Adds commands for interacting with MTD partitions formatted
2971 with the UBI flash translation layer
2973 Requires also defining CONFIG_RBTREE
2975 CONFIG_UBI_SILENCE_MSG
2977 Make the verbose messages from UBI stop printing. This leaves
2978 warnings and errors enabled.
2983 Adds commands for interacting with UBI volumes formatted as
2984 UBIFS. UBIFS is read-only in u-boot.
2986 Requires UBI support as well as CONFIG_LZO
2988 CONFIG_UBIFS_SILENCE_MSG
2990 Make the verbose messages from UBIFS stop printing. This leaves
2991 warnings and errors enabled.
2995 Enable building of SPL globally.
2998 LDSCRIPT for linking the SPL binary.
3000 CONFIG_SPL_MAX_FOOTPRINT
3001 Maximum size in memory allocated to the SPL, BSS included.
3002 When defined, the linker checks that the actual memory
3003 used by SPL from _start to __bss_end does not exceed it.
3004 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
3005 must not be both defined at the same time.
3008 Maximum size of the SPL image (text, data, rodata, and
3009 linker lists sections), BSS excluded.
3010 When defined, the linker checks that the actual size does
3013 CONFIG_SPL_TEXT_BASE
3014 TEXT_BASE for linking the SPL binary.
3016 CONFIG_SPL_RELOC_TEXT_BASE
3017 Address to relocate to. If unspecified, this is equal to
3018 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done).
3020 CONFIG_SPL_BSS_START_ADDR
3021 Link address for the BSS within the SPL binary.
3023 CONFIG_SPL_BSS_MAX_SIZE
3024 Maximum size in memory allocated to the SPL BSS.
3025 When defined, the linker checks that the actual memory used
3026 by SPL from __bss_start to __bss_end does not exceed it.
3027 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
3028 must not be both defined at the same time.
3031 Adress of the start of the stack SPL will use
3033 CONFIG_SPL_RELOC_STACK
3034 Adress of the start of the stack SPL will use after
3035 relocation. If unspecified, this is equal to
3038 CONFIG_SYS_SPL_MALLOC_START
3039 Starting address of the malloc pool used in SPL.
3041 CONFIG_SYS_SPL_MALLOC_SIZE
3042 The size of the malloc pool used in SPL.
3044 CONFIG_SPL_FRAMEWORK
3045 Enable the SPL framework under common/. This framework
3046 supports MMC, NAND and YMODEM loading of U-Boot and NAND
3047 NAND loading of the Linux Kernel.
3049 CONFIG_SPL_DISPLAY_PRINT
3050 For ARM, enable an optional function to print more information
3051 about the running system.
3053 CONFIG_SPL_INIT_MINIMAL
3054 Arch init code should be built for a very small image
3056 CONFIG_SPL_LIBCOMMON_SUPPORT
3057 Support for common/libcommon.o in SPL binary
3059 CONFIG_SPL_LIBDISK_SUPPORT
3060 Support for disk/libdisk.o in SPL binary
3062 CONFIG_SPL_I2C_SUPPORT
3063 Support for drivers/i2c/libi2c.o in SPL binary
3065 CONFIG_SPL_GPIO_SUPPORT
3066 Support for drivers/gpio/libgpio.o in SPL binary
3068 CONFIG_SPL_MMC_SUPPORT
3069 Support for drivers/mmc/libmmc.o in SPL binary
3071 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR,
3072 CONFIG_SYS_U_BOOT_MAX_SIZE_SECTORS,
3073 CONFIG_SYS_MMC_SD_FAT_BOOT_PARTITION
3074 Address, size and partition on the MMC to load U-Boot from
3075 when the MMC is being used in raw mode.
3077 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR
3078 Sector to load kernel uImage from when MMC is being
3079 used in raw mode (for Falcon mode)
3081 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR,
3082 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS
3083 Sector and number of sectors to load kernel argument
3084 parameters from when MMC is being used in raw mode
3087 CONFIG_SPL_FAT_SUPPORT
3088 Support for fs/fat/libfat.o in SPL binary
3090 CONFIG_SPL_FAT_LOAD_PAYLOAD_NAME
3091 Filename to read to load U-Boot when reading from FAT
3093 CONFIG_SPL_FAT_LOAD_KERNEL_NAME
3094 Filename to read to load kernel uImage when reading
3095 from FAT (for Falcon mode)
3097 CONFIG_SPL_FAT_LOAD_ARGS_NAME
3098 Filename to read to load kernel argument parameters
3099 when reading from FAT (for Falcon mode)
3101 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND
3102 Set this for NAND SPL on PPC mpc83xx targets, so that
3103 start.S waits for the rest of the SPL to load before
3104 continuing (the hardware starts execution after just
3105 loading the first page rather than the full 4K).
3107 CONFIG_SPL_NAND_BASE
3108 Include nand_base.c in the SPL. Requires
3109 CONFIG_SPL_NAND_DRIVERS.
3111 CONFIG_SPL_NAND_DRIVERS
3112 SPL uses normal NAND drivers, not minimal drivers.
3115 Include standard software ECC in the SPL
3117 CONFIG_SPL_NAND_SIMPLE
3118 Support for NAND boot using simple NAND drivers that
3119 expose the cmd_ctrl() interface.
3121 CONFIG_SPL_MPC8XXX_INIT_DDR_SUPPORT
3122 Set for the SPL on PPC mpc8xxx targets, support for
3123 arch/powerpc/cpu/mpc8xxx/ddr/libddr.o in SPL binary.
3125 CONFIG_SPL_COMMON_INIT_DDR
3126 Set for common ddr init with serial presence detect in
3129 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
3130 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
3131 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
3132 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE,
3133 CONFIG_SYS_NAND_ECCBYTES
3134 Defines the size and behavior of the NAND that SPL uses
3137 CONFIG_SYS_NAND_U_BOOT_OFFS
3138 Location in NAND to read U-Boot from
3140 CONFIG_SYS_NAND_U_BOOT_DST
3141 Location in memory to load U-Boot to
3143 CONFIG_SYS_NAND_U_BOOT_SIZE
3144 Size of image to load
3146 CONFIG_SYS_NAND_U_BOOT_START
3147 Entry point in loaded image to jump to
3149 CONFIG_SYS_NAND_HW_ECC_OOBFIRST
3150 Define this if you need to first read the OOB and then the
3151 data. This is used for example on davinci plattforms.
3153 CONFIG_SPL_OMAP3_ID_NAND
3154 Support for an OMAP3-specific set of functions to return the
3155 ID and MFR of the first attached NAND chip, if present.
3157 CONFIG_SPL_SERIAL_SUPPORT
3158 Support for drivers/serial/libserial.o in SPL binary
3160 CONFIG_SPL_SPI_FLASH_SUPPORT
3161 Support for drivers/mtd/spi/libspi_flash.o in SPL binary
3163 CONFIG_SPL_SPI_SUPPORT
3164 Support for drivers/spi/libspi.o in SPL binary
3166 CONFIG_SPL_RAM_DEVICE
3167 Support for running image already present in ram, in SPL binary
3169 CONFIG_SPL_LIBGENERIC_SUPPORT
3170 Support for lib/libgeneric.o in SPL binary
3172 CONFIG_SPL_ENV_SUPPORT
3173 Support for the environment operating in SPL binary
3175 CONFIG_SPL_NET_SUPPORT
3176 Support for the net/libnet.o in SPL binary.
3177 It conflicts with SPL env from storage medium specified by
3178 CONFIG_ENV_IS_xxx but CONFIG_ENV_IS_NOWHERE
3181 Image offset to which the SPL should be padded before appending
3182 the SPL payload. By default, this is defined as
3183 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
3184 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
3185 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
3188 Final target image containing SPL and payload. Some SPLs
3189 use an arch-specific makefile fragment instead, for
3190 example if more than one image needs to be produced.
3192 CONFIG_FIT_SPL_PRINT
3193 Printing information about a FIT image adds quite a bit of
3194 code to SPL. So this is normally disabled in SPL. Use this
3195 option to re-enable it. This will affect the output of the
3196 bootm command when booting a FIT image.
3200 Enable building of TPL globally.
3203 Image offset to which the TPL should be padded before appending
3204 the TPL payload. By default, this is defined as
3205 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
3206 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
3207 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
3212 [so far only for SMDK2400 boards]
3214 - Modem support enable:
3215 CONFIG_MODEM_SUPPORT
3217 - RTS/CTS Flow control enable:
3220 - Modem debug support:
3221 CONFIG_MODEM_SUPPORT_DEBUG
3223 Enables debugging stuff (char screen[1024], dbg())
3224 for modem support. Useful only with BDI2000.
3226 - Interrupt support (PPC):
3228 There are common interrupt_init() and timer_interrupt()
3229 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
3230 for CPU specific initialization. interrupt_init_cpu()
3231 should set decrementer_count to appropriate value. If
3232 CPU resets decrementer automatically after interrupt
3233 (ppc4xx) it should set decrementer_count to zero.
3234 timer_interrupt() calls timer_interrupt_cpu() for CPU
3235 specific handling. If board has watchdog / status_led
3236 / other_activity_monitor it works automatically from
3237 general timer_interrupt().
3241 In the target system modem support is enabled when a
3242 specific key (key combination) is pressed during
3243 power-on. Otherwise U-Boot will boot normally
3244 (autoboot). The key_pressed() function is called from
3245 board_init(). Currently key_pressed() is a dummy
3246 function, returning 1 and thus enabling modem
3249 If there are no modem init strings in the
3250 environment, U-Boot proceed to autoboot; the
3251 previous output (banner, info printfs) will be
3254 See also: doc/README.Modem
3256 Board initialization settings:
3257 ------------------------------
3259 During Initialization u-boot calls a number of board specific functions
3260 to allow the preparation of board specific prerequisites, e.g. pin setup
3261 before drivers are initialized. To enable these callbacks the
3262 following configuration macros have to be defined. Currently this is
3263 architecture specific, so please check arch/your_architecture/lib/board.c
3264 typically in board_init_f() and board_init_r().
3266 - CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
3267 - CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
3268 - CONFIG_BOARD_LATE_INIT: Call board_late_init()
3269 - CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init()
3271 Configuration Settings:
3272 -----------------------
3274 - CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
3275 undefine this when you're short of memory.
3277 - CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
3278 width of the commands listed in the 'help' command output.
3280 - CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
3281 prompt for user input.
3283 - CONFIG_SYS_CBSIZE: Buffer size for input from the Console
3285 - CONFIG_SYS_PBSIZE: Buffer size for Console output
3287 - CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
3289 - CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
3290 the application (usually a Linux kernel) when it is
3293 - CONFIG_SYS_BAUDRATE_TABLE:
3294 List of legal baudrate settings for this board.
3296 - CONFIG_SYS_CONSOLE_INFO_QUIET
3297 Suppress display of console information at boot.
3299 - CONFIG_SYS_CONSOLE_IS_IN_ENV
3300 If the board specific function
3301 extern int overwrite_console (void);
3302 returns 1, the stdin, stderr and stdout are switched to the
3303 serial port, else the settings in the environment are used.
3305 - CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE
3306 Enable the call to overwrite_console().
3308 - CONFIG_SYS_CONSOLE_ENV_OVERWRITE
3309 Enable overwrite of previous console environment settings.
3311 - CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
3312 Begin and End addresses of the area used by the
3315 - CONFIG_SYS_ALT_MEMTEST:
3316 Enable an alternate, more extensive memory test.
3318 - CONFIG_SYS_MEMTEST_SCRATCH:
3319 Scratch address used by the alternate memory test
3320 You only need to set this if address zero isn't writeable
3322 - CONFIG_SYS_MEM_TOP_HIDE (PPC only):
3323 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
3324 this specified memory area will get subtracted from the top
3325 (end) of RAM and won't get "touched" at all by U-Boot. By
3326 fixing up gd->ram_size the Linux kernel should gets passed
3327 the now "corrected" memory size and won't touch it either.
3328 This should work for arch/ppc and arch/powerpc. Only Linux
3329 board ports in arch/powerpc with bootwrapper support that
3330 recalculate the memory size from the SDRAM controller setup
3331 will have to get fixed in Linux additionally.
3333 This option can be used as a workaround for the 440EPx/GRx
3334 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
3337 WARNING: Please make sure that this value is a multiple of
3338 the Linux page size (normally 4k). If this is not the case,
3339 then the end address of the Linux memory will be located at a
3340 non page size aligned address and this could cause major
3343 - CONFIG_SYS_LOADS_BAUD_CHANGE:
3344 Enable temporary baudrate change while serial download
3346 - CONFIG_SYS_SDRAM_BASE:
3347 Physical start address of SDRAM. _Must_ be 0 here.
3349 - CONFIG_SYS_MBIO_BASE:
3350 Physical start address of Motherboard I/O (if using a
3353 - CONFIG_SYS_FLASH_BASE:
3354 Physical start address of Flash memory.
3356 - CONFIG_SYS_MONITOR_BASE:
3357 Physical start address of boot monitor code (set by
3358 make config files to be same as the text base address
3359 (CONFIG_SYS_TEXT_BASE) used when linking) - same as
3360 CONFIG_SYS_FLASH_BASE when booting from flash.
3362 - CONFIG_SYS_MONITOR_LEN:
3363 Size of memory reserved for monitor code, used to
3364 determine _at_compile_time_ (!) if the environment is
3365 embedded within the U-Boot image, or in a separate
3368 - CONFIG_SYS_MALLOC_LEN:
3369 Size of DRAM reserved for malloc() use.
3371 - CONFIG_SYS_BOOTM_LEN:
3372 Normally compressed uImages are limited to an
3373 uncompressed size of 8 MBytes. If this is not enough,
3374 you can define CONFIG_SYS_BOOTM_LEN in your board config file
3375 to adjust this setting to your needs.
3377 - CONFIG_SYS_BOOTMAPSZ:
3378 Maximum size of memory mapped by the startup code of
3379 the Linux kernel; all data that must be processed by
3380 the Linux kernel (bd_info, boot arguments, FDT blob if
3381 used) must be put below this limit, unless "bootm_low"
3382 environment variable is defined and non-zero. In such case
3383 all data for the Linux kernel must be between "bootm_low"
3384 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
3385 variable "bootm_mapsize" will override the value of
3386 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
3387 then the value in "bootm_size" will be used instead.
3389 - CONFIG_SYS_BOOT_RAMDISK_HIGH:
3390 Enable initrd_high functionality. If defined then the
3391 initrd_high feature is enabled and the bootm ramdisk subcommand
3394 - CONFIG_SYS_BOOT_GET_CMDLINE:
3395 Enables allocating and saving kernel cmdline in space between
3396 "bootm_low" and "bootm_low" + BOOTMAPSZ.
3398 - CONFIG_SYS_BOOT_GET_KBD:
3399 Enables allocating and saving a kernel copy of the bd_info in
3400 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
3402 - CONFIG_SYS_MAX_FLASH_BANKS:
3403 Max number of Flash memory banks
3405 - CONFIG_SYS_MAX_FLASH_SECT:
3406 Max number of sectors on a Flash chip
3408 - CONFIG_SYS_FLASH_ERASE_TOUT:
3409 Timeout for Flash erase operations (in ms)
3411 - CONFIG_SYS_FLASH_WRITE_TOUT:
3412 Timeout for Flash write operations (in ms)
3414 - CONFIG_SYS_FLASH_LOCK_TOUT
3415 Timeout for Flash set sector lock bit operation (in ms)
3417 - CONFIG_SYS_FLASH_UNLOCK_TOUT
3418 Timeout for Flash clear lock bits operation (in ms)
3420 - CONFIG_SYS_FLASH_PROTECTION
3421 If defined, hardware flash sectors protection is used
3422 instead of U-Boot software protection.
3424 - CONFIG_SYS_DIRECT_FLASH_TFTP:
3426 Enable TFTP transfers directly to flash memory;
3427 without this option such a download has to be
3428 performed in two steps: (1) download to RAM, and (2)
3429 copy from RAM to flash.
3431 The two-step approach is usually more reliable, since
3432 you can check if the download worked before you erase
3433 the flash, but in some situations (when system RAM is
3434 too limited to allow for a temporary copy of the
3435 downloaded image) this option may be very useful.
3437 - CONFIG_SYS_FLASH_CFI:
3438 Define if the flash driver uses extra elements in the
3439 common flash structure for storing flash geometry.
3441 - CONFIG_FLASH_CFI_DRIVER
3442 This option also enables the building of the cfi_flash driver
3443 in the drivers directory
3445 - CONFIG_FLASH_CFI_MTD
3446 This option enables the building of the cfi_mtd driver
3447 in the drivers directory. The driver exports CFI flash
3450 - CONFIG_SYS_FLASH_USE_BUFFER_WRITE
3451 Use buffered writes to flash.
3453 - CONFIG_FLASH_SPANSION_S29WS_N
3454 s29ws-n MirrorBit flash has non-standard addresses for buffered
3457 - CONFIG_SYS_FLASH_QUIET_TEST
3458 If this option is defined, the common CFI flash doesn't
3459 print it's warning upon not recognized FLASH banks. This
3460 is useful, if some of the configured banks are only
3461 optionally available.
3463 - CONFIG_FLASH_SHOW_PROGRESS
3464 If defined (must be an integer), print out countdown
3465 digits and dots. Recommended value: 45 (9..1) for 80
3466 column displays, 15 (3..1) for 40 column displays.
3468 - CONFIG_FLASH_VERIFY
3469 If defined, the content of the flash (destination) is compared
3470 against the source after the write operation. An error message
3471 will be printed when the contents are not identical.
3472 Please note that this option is useless in nearly all cases,
3473 since such flash programming errors usually are detected earlier
3474 while unprotecting/erasing/programming. Please only enable
3475 this option if you really know what you are doing.
3477 - CONFIG_SYS_RX_ETH_BUFFER:
3478 Defines the number of Ethernet receive buffers. On some
3479 Ethernet controllers it is recommended to set this value
3480 to 8 or even higher (EEPRO100 or 405 EMAC), since all
3481 buffers can be full shortly after enabling the interface
3482 on high Ethernet traffic.
3483 Defaults to 4 if not defined.
3485 - CONFIG_ENV_MAX_ENTRIES
3487 Maximum number of entries in the hash table that is used
3488 internally to store the environment settings. The default
3489 setting is supposed to be generous and should work in most
3490 cases. This setting can be used to tune behaviour; see
3491 lib/hashtable.c for details.
3493 - CONFIG_ENV_FLAGS_LIST_DEFAULT
3494 - CONFIG_ENV_FLAGS_LIST_STATIC
3495 Enable validation of the values given to environment variables when
3496 calling env set. Variables can be restricted to only decimal,
3497 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined,
3498 the variables can also be restricted to IP address or MAC address.
3500 The format of the list is:
3501 type_attribute = [s|d|x|b|i|m]
3502 access_atribute = [a|r|o|c]
3503 attributes = type_attribute[access_atribute]
3504 entry = variable_name[:attributes]
3507 The type attributes are:
3508 s - String (default)
3511 b - Boolean ([1yYtT|0nNfF])
3515 The access attributes are:
3521 - CONFIG_ENV_FLAGS_LIST_DEFAULT
3522 Define this to a list (string) to define the ".flags"
3523 envirnoment variable in the default or embedded environment.
3525 - CONFIG_ENV_FLAGS_LIST_STATIC
3526 Define this to a list (string) to define validation that
3527 should be done if an entry is not found in the ".flags"
3528 environment variable. To override a setting in the static
3529 list, simply add an entry for the same variable name to the
3532 - CONFIG_ENV_ACCESS_IGNORE_FORCE
3533 If defined, don't allow the -f switch to env set override variable
3536 - CONFIG_SYS_GENERIC_BOARD
3537 This selects the architecture-generic board system instead of the
3538 architecture-specific board files. It is intended to move boards
3539 to this new framework over time. Defining this will disable the
3540 arch/foo/lib/board.c file and use common/board_f.c and
3541 common/board_r.c instead. To use this option your architecture
3542 must support it (i.e. must define __HAVE_ARCH_GENERIC_BOARD in
3543 its config.mk file). If you find problems enabling this option on
3544 your board please report the problem and send patches!
3546 - CONFIG_SYS_SYM_OFFSETS
3547 This is set by architectures that use offsets for link symbols
3548 instead of absolute values. So bss_start is obtained using an
3549 offset _bss_start_ofs from CONFIG_SYS_TEXT_BASE, rather than
3550 directly. You should not need to touch this setting.
3552 - CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC (OMAP only)
3553 This is set by OMAP boards for the max time that reset should
3554 be asserted. See doc/README.omap-reset-time for details on how
3555 the value can be calulated on a given board.
3557 The following definitions that deal with the placement and management
3558 of environment data (variable area); in general, we support the
3559 following configurations:
3561 - CONFIG_BUILD_ENVCRC:
3563 Builds up envcrc with the target environment so that external utils
3564 may easily extract it and embed it in final U-Boot images.
3566 - CONFIG_ENV_IS_IN_FLASH:
3568 Define this if the environment is in flash memory.
3570 a) The environment occupies one whole flash sector, which is
3571 "embedded" in the text segment with the U-Boot code. This
3572 happens usually with "bottom boot sector" or "top boot
3573 sector" type flash chips, which have several smaller
3574 sectors at the start or the end. For instance, such a
3575 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
3576 such a case you would place the environment in one of the
3577 4 kB sectors - with U-Boot code before and after it. With
3578 "top boot sector" type flash chips, you would put the
3579 environment in one of the last sectors, leaving a gap
3580 between U-Boot and the environment.
3582 - CONFIG_ENV_OFFSET:
3584 Offset of environment data (variable area) to the
3585 beginning of flash memory; for instance, with bottom boot
3586 type flash chips the second sector can be used: the offset
3587 for this sector is given here.
3589 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE.
3593 This is just another way to specify the start address of
3594 the flash sector containing the environment (instead of
3597 - CONFIG_ENV_SECT_SIZE:
3599 Size of the sector containing the environment.
3602 b) Sometimes flash chips have few, equal sized, BIG sectors.
3603 In such a case you don't want to spend a whole sector for
3608 If you use this in combination with CONFIG_ENV_IS_IN_FLASH
3609 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part
3610 of this flash sector for the environment. This saves
3611 memory for the RAM copy of the environment.
3613 It may also save flash memory if you decide to use this
3614 when your environment is "embedded" within U-Boot code,
3615 since then the remainder of the flash sector could be used
3616 for U-Boot code. It should be pointed out that this is
3617 STRONGLY DISCOURAGED from a robustness point of view:
3618 updating the environment in flash makes it always
3619 necessary to erase the WHOLE sector. If something goes
3620 wrong before the contents has been restored from a copy in
3621 RAM, your target system will be dead.
3623 - CONFIG_ENV_ADDR_REDUND
3624 CONFIG_ENV_SIZE_REDUND
3626 These settings describe a second storage area used to hold
3627 a redundant copy of the environment data, so that there is
3628 a valid backup copy in case there is a power failure during
3629 a "saveenv" operation.
3631 BE CAREFUL! Any changes to the flash layout, and some changes to the
3632 source code will make it necessary to adapt <board>/u-boot.lds*
3636 - CONFIG_ENV_IS_IN_NVRAM:
3638 Define this if you have some non-volatile memory device
3639 (NVRAM, battery buffered SRAM) which you want to use for the
3645 These two #defines are used to determine the memory area you
3646 want to use for environment. It is assumed that this memory
3647 can just be read and written to, without any special
3650 BE CAREFUL! The first access to the environment happens quite early
3651 in U-Boot initalization (when we try to get the setting of for the
3652 console baudrate). You *MUST* have mapped your NVRAM area then, or
3655 Please note that even with NVRAM we still use a copy of the
3656 environment in RAM: we could work on NVRAM directly, but we want to
3657 keep settings there always unmodified except somebody uses "saveenv"
3658 to save the current settings.
3661 - CONFIG_ENV_IS_IN_EEPROM:
3663 Use this if you have an EEPROM or similar serial access
3664 device and a driver for it.
3666 - CONFIG_ENV_OFFSET:
3669 These two #defines specify the offset and size of the
3670 environment area within the total memory of your EEPROM.
3672 - CONFIG_SYS_I2C_EEPROM_ADDR:
3673 If defined, specified the chip address of the EEPROM device.
3674 The default address is zero.
3676 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS:
3677 If defined, the number of bits used to address bytes in a
3678 single page in the EEPROM device. A 64 byte page, for example
3679 would require six bits.
3681 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS:
3682 If defined, the number of milliseconds to delay between
3683 page writes. The default is zero milliseconds.
3685 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN:
3686 The length in bytes of the EEPROM memory array address. Note
3687 that this is NOT the chip address length!
3689 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW:
3690 EEPROM chips that implement "address overflow" are ones
3691 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
3692 address and the extra bits end up in the "chip address" bit
3693 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
3696 Note that we consider the length of the address field to
3697 still be one byte because the extra address bits are hidden
3698 in the chip address.
3700 - CONFIG_SYS_EEPROM_SIZE:
3701 The size in bytes of the EEPROM device.
3703 - CONFIG_ENV_EEPROM_IS_ON_I2C
3704 define this, if you have I2C and SPI activated, and your
3705 EEPROM, which holds the environment, is on the I2C bus.
3707 - CONFIG_I2C_ENV_EEPROM_BUS
3708 if you have an Environment on an EEPROM reached over
3709 I2C muxes, you can define here, how to reach this
3710 EEPROM. For example:
3712 #define CONFIG_I2C_ENV_EEPROM_BUS 1
3714 EEPROM which holds the environment, is reached over
3715 a pca9547 i2c mux with address 0x70, channel 3.
3717 - CONFIG_ENV_IS_IN_DATAFLASH:
3719 Define this if you have a DataFlash memory device which you
3720 want to use for the environment.
3722 - CONFIG_ENV_OFFSET:
3726 These three #defines specify the offset and size of the
3727 environment area within the total memory of your DataFlash placed
3728 at the specified address.
3730 - CONFIG_ENV_IS_IN_REMOTE:
3732 Define this if you have a remote memory space which you
3733 want to use for the local device's environment.
3738 These two #defines specify the address and size of the
3739 environment area within the remote memory space. The
3740 local device can get the environment from remote memory
3741 space by SRIO or PCIE links.
3743 BE CAREFUL! For some special cases, the local device can not use
3744 "saveenv" command. For example, the local device will get the
3745 environment stored in a remote NOR flash by SRIO or PCIE link,
3746 but it can not erase, write this NOR flash by SRIO or PCIE interface.
3748 - CONFIG_ENV_IS_IN_NAND:
3750 Define this if you have a NAND device which you want to use
3751 for the environment.
3753 - CONFIG_ENV_OFFSET:
3756 These two #defines specify the offset and size of the environment
3757 area within the first NAND device. CONFIG_ENV_OFFSET must be
3758 aligned to an erase block boundary.
3760 - CONFIG_ENV_OFFSET_REDUND (optional):
3762 This setting describes a second storage area of CONFIG_ENV_SIZE
3763 size used to hold a redundant copy of the environment data, so
3764 that there is a valid backup copy in case there is a power failure
3765 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be
3766 aligned to an erase block boundary.
3768 - CONFIG_ENV_RANGE (optional):
3770 Specifies the length of the region in which the environment
3771 can be written. This should be a multiple of the NAND device's
3772 block size. Specifying a range with more erase blocks than
3773 are needed to hold CONFIG_ENV_SIZE allows bad blocks within
3774 the range to be avoided.
3776 - CONFIG_ENV_OFFSET_OOB (optional):
3778 Enables support for dynamically retrieving the offset of the
3779 environment from block zero's out-of-band data. The
3780 "nand env.oob" command can be used to record this offset.
3781 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when
3782 using CONFIG_ENV_OFFSET_OOB.
3784 - CONFIG_NAND_ENV_DST
3786 Defines address in RAM to which the nand_spl code should copy the
3787 environment. If redundant environment is used, it will be copied to
3788 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
3790 - CONFIG_ENV_IS_IN_UBI:
3792 Define this if you have an UBI volume that you want to use for the
3793 environment. This has the benefit of wear-leveling the environment
3794 accesses, which is important on NAND.
3796 - CONFIG_ENV_UBI_PART:
3798 Define this to a string that is the mtd partition containing the UBI.
3800 - CONFIG_ENV_UBI_VOLUME:
3802 Define this to the name of the volume that you want to store the
3805 - CONFIG_ENV_UBI_VOLUME_REDUND:
3807 Define this to the name of another volume to store a second copy of
3808 the environment in. This will enable redundant environments in UBI.
3809 It is assumed that both volumes are in the same MTD partition.
3811 - CONFIG_UBI_SILENCE_MSG
3812 - CONFIG_UBIFS_SILENCE_MSG
3814 You will probably want to define these to avoid a really noisy system
3815 when storing the env in UBI.
3817 - CONFIG_ENV_IS_IN_MMC:
3819 Define this if you have an MMC device which you want to use for the
3822 - CONFIG_SYS_MMC_ENV_DEV:
3824 Specifies which MMC device the environment is stored in.
3826 - CONFIG_SYS_MMC_ENV_PART (optional):
3828 Specifies which MMC partition the environment is stored in. If not
3829 set, defaults to partition 0, the user area. Common values might be
3830 1 (first MMC boot partition), 2 (second MMC boot partition).
3832 - CONFIG_ENV_OFFSET:
3835 These two #defines specify the offset and size of the environment
3836 area within the specified MMC device.
3838 If offset is positive (the usual case), it is treated as relative to
3839 the start of the MMC partition. If offset is negative, it is treated
3840 as relative to the end of the MMC partition. This can be useful if
3841 your board may be fitted with different MMC devices, which have
3842 different sizes for the MMC partitions, and you always want the
3843 environment placed at the very end of the partition, to leave the
3844 maximum possible space before it, to store other data.
3846 These two values are in units of bytes, but must be aligned to an
3847 MMC sector boundary.
3849 - CONFIG_ENV_OFFSET_REDUND (optional):
3851 Specifies a second storage area, of CONFIG_ENV_SIZE size, used to
3852 hold a redundant copy of the environment data. This provides a
3853 valid backup copy in case the other copy is corrupted, e.g. due
3854 to a power failure during a "saveenv" operation.
3856 This value may also be positive or negative; this is handled in the
3857 same way as CONFIG_ENV_OFFSET.
3859 This value is also in units of bytes, but must also be aligned to
3860 an MMC sector boundary.
3862 - CONFIG_ENV_SIZE_REDUND (optional):
3864 This value need not be set, even when CONFIG_ENV_OFFSET_REDUND is
3865 set. If this value is set, it must be set to the same value as
3868 - CONFIG_SYS_SPI_INIT_OFFSET
3870 Defines offset to the initial SPI buffer area in DPRAM. The
3871 area is used at an early stage (ROM part) if the environment
3872 is configured to reside in the SPI EEPROM: We need a 520 byte
3873 scratch DPRAM area. It is used between the two initialization
3874 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
3875 to be a good choice since it makes it far enough from the
3876 start of the data area as well as from the stack pointer.
3878 Please note that the environment is read-only until the monitor
3879 has been relocated to RAM and a RAM copy of the environment has been
3880 created; also, when using EEPROM you will have to use getenv_f()
3881 until then to read environment variables.
3883 The environment is protected by a CRC32 checksum. Before the monitor
3884 is relocated into RAM, as a result of a bad CRC you will be working
3885 with the compiled-in default environment - *silently*!!! [This is
3886 necessary, because the first environment variable we need is the
3887 "baudrate" setting for the console - if we have a bad CRC, we don't
3888 have any device yet where we could complain.]
3890 Note: once the monitor has been relocated, then it will complain if
3891 the default environment is used; a new CRC is computed as soon as you
3892 use the "saveenv" command to store a valid environment.
3894 - CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
3895 Echo the inverted Ethernet link state to the fault LED.
3897 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
3898 also needs to be defined.
3900 - CONFIG_SYS_FAULT_MII_ADDR:
3901 MII address of the PHY to check for the Ethernet link state.
3903 - CONFIG_NS16550_MIN_FUNCTIONS:
3904 Define this if you desire to only have use of the NS16550_init
3905 and NS16550_putc functions for the serial driver located at
3906 drivers/serial/ns16550.c. This option is useful for saving
3907 space for already greatly restricted images, including but not
3908 limited to NAND_SPL configurations.
3910 - CONFIG_DISPLAY_BOARDINFO
3911 Display information about the board that U-Boot is running on
3912 when U-Boot starts up. The board function checkboard() is called
3915 - CONFIG_DISPLAY_BOARDINFO_LATE
3916 Similar to the previous option, but display this information
3917 later, once stdio is running and output goes to the LCD, if
3920 Low Level (hardware related) configuration options:
3921 ---------------------------------------------------
3923 - CONFIG_SYS_CACHELINE_SIZE:
3924 Cache Line Size of the CPU.
3926 - CONFIG_SYS_DEFAULT_IMMR:
3927 Default address of the IMMR after system reset.
3929 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
3930 and RPXsuper) to be able to adjust the position of
3931 the IMMR register after a reset.
3933 - CONFIG_SYS_CCSRBAR_DEFAULT:
3934 Default (power-on reset) physical address of CCSR on Freescale
3937 - CONFIG_SYS_CCSRBAR:
3938 Virtual address of CCSR. On a 32-bit build, this is typically
3939 the same value as CONFIG_SYS_CCSRBAR_DEFAULT.
3941 CONFIG_SYS_DEFAULT_IMMR must also be set to this value,
3942 for cross-platform code that uses that macro instead.
3944 - CONFIG_SYS_CCSRBAR_PHYS:
3945 Physical address of CCSR. CCSR can be relocated to a new
3946 physical address, if desired. In this case, this macro should
3947 be set to that address. Otherwise, it should be set to the
3948 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR
3949 is typically relocated on 36-bit builds. It is recommended
3950 that this macro be defined via the _HIGH and _LOW macros:
3952 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH
3953 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW)
3955 - CONFIG_SYS_CCSRBAR_PHYS_HIGH:
3956 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically
3957 either 0 (32-bit build) or 0xF (36-bit build). This macro is
3958 used in assembly code, so it must not contain typecasts or
3959 integer size suffixes (e.g. "ULL").
3961 - CONFIG_SYS_CCSRBAR_PHYS_LOW:
3962 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is
3963 used in assembly code, so it must not contain typecasts or
3964 integer size suffixes (e.g. "ULL").
3966 - CONFIG_SYS_CCSR_DO_NOT_RELOCATE:
3967 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be
3968 forced to a value that ensures that CCSR is not relocated.
3970 - Floppy Disk Support:
3971 CONFIG_SYS_FDC_DRIVE_NUMBER
3973 the default drive number (default value 0)
3975 CONFIG_SYS_ISA_IO_STRIDE
3977 defines the spacing between FDC chipset registers
3980 CONFIG_SYS_ISA_IO_OFFSET
3982 defines the offset of register from address. It
3983 depends on which part of the data bus is connected to
3984 the FDC chipset. (default value 0)
3986 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
3987 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
3990 if CONFIG_SYS_FDC_HW_INIT is defined, then the function
3991 fdc_hw_init() is called at the beginning of the FDC
3992 setup. fdc_hw_init() must be provided by the board
3993 source code. It is used to make hardware dependant
3997 Most IDE controllers were designed to be connected with PCI
3998 interface. Only few of them were designed for AHB interface.
3999 When software is doing ATA command and data transfer to
4000 IDE devices through IDE-AHB controller, some additional
4001 registers accessing to these kind of IDE-AHB controller
4004 - CONFIG_SYS_IMMR: Physical address of the Internal Memory.
4005 DO NOT CHANGE unless you know exactly what you're
4006 doing! (11-4) [MPC8xx/82xx systems only]
4008 - CONFIG_SYS_INIT_RAM_ADDR:
4010 Start address of memory area that can be used for
4011 initial data and stack; please note that this must be
4012 writable memory that is working WITHOUT special
4013 initialization, i. e. you CANNOT use normal RAM which
4014 will become available only after programming the
4015 memory controller and running certain initialization
4018 U-Boot uses the following memory types:
4019 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
4020 - MPC824X: data cache
4021 - PPC4xx: data cache
4023 - CONFIG_SYS_GBL_DATA_OFFSET:
4025 Offset of the initial data structure in the memory
4026 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
4027 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
4028 data is located at the end of the available space
4029 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
4030 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just
4031 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
4032 CONFIG_SYS_GBL_DATA_OFFSET) downward.
4035 On the MPC824X (or other systems that use the data
4036 cache for initial memory) the address chosen for
4037 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
4038 point to an otherwise UNUSED address space between
4039 the top of RAM and the start of the PCI space.
4041 - CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6)
4043 - CONFIG_SYS_SYPCR: System Protection Control (11-9)
4045 - CONFIG_SYS_TBSCR: Time Base Status and Control (11-26)
4047 - CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31)
4049 - CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
4051 - CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
4053 - CONFIG_SYS_OR_TIMING_SDRAM:
4056 - CONFIG_SYS_MAMR_PTA:
4057 periodic timer for refresh
4059 - CONFIG_SYS_DER: Debug Event Register (37-47)
4061 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
4062 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
4063 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
4064 CONFIG_SYS_BR1_PRELIM:
4065 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
4067 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
4068 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
4069 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
4070 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
4072 - CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K,
4073 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL:
4074 Machine Mode Register and Memory Periodic Timer
4075 Prescaler definitions (SDRAM timing)
4077 - CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]:
4078 enable I2C microcode relocation patch (MPC8xx);
4079 define relocation offset in DPRAM [DSP2]
4081 - CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]:
4082 enable SMC microcode relocation patch (MPC8xx);
4083 define relocation offset in DPRAM [SMC1]
4085 - CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]:
4086 enable SPI microcode relocation patch (MPC8xx);
4087 define relocation offset in DPRAM [SCC4]
4089 - CONFIG_SYS_USE_OSCCLK:
4090 Use OSCM clock mode on MBX8xx board. Be careful,
4091 wrong setting might damage your board. Read
4092 doc/README.MBX before setting this variable!
4094 - CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
4095 Offset of the bootmode word in DPRAM used by post
4096 (Power On Self Tests). This definition overrides
4097 #define'd default value in commproc.h resp.
4100 - CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB,
4101 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL,
4102 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS,
4103 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB,
4104 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
4105 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL,
4106 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE,
4107 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only)
4108 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set.
4110 - CONFIG_PCI_DISABLE_PCIE:
4111 Disable PCI-Express on systems where it is supported but not
4114 - CONFIG_PCI_ENUM_ONLY
4115 Only scan through and get the devices on the busses.
4116 Don't do any setup work, presumably because someone or
4117 something has already done it, and we don't need to do it
4118 a second time. Useful for platforms that are pre-booted
4119 by coreboot or similar.
4121 - CONFIG_PCI_INDIRECT_BRIDGE:
4122 Enable support for indirect PCI bridges.
4125 Chip has SRIO or not
4128 Board has SRIO 1 port available
4131 Board has SRIO 2 port available
4133 - CONFIG_SRIO_PCIE_BOOT_MASTER
4134 Board can support master function for Boot from SRIO and PCIE
4136 - CONFIG_SYS_SRIOn_MEM_VIRT:
4137 Virtual Address of SRIO port 'n' memory region
4139 - CONFIG_SYS_SRIOn_MEM_PHYS:
4140 Physical Address of SRIO port 'n' memory region
4142 - CONFIG_SYS_SRIOn_MEM_SIZE:
4143 Size of SRIO port 'n' memory region
4145 - CONFIG_SYS_NAND_BUSWIDTH_16BIT
4146 Defined to tell the NAND controller that the NAND chip is using
4148 Not all NAND drivers use this symbol.
4149 Example of drivers that use it:
4150 - drivers/mtd/nand/ndfc.c
4151 - drivers/mtd/nand/mxc_nand.c
4153 - CONFIG_SYS_NDFC_EBC0_CFG
4154 Sets the EBC0_CFG register for the NDFC. If not defined
4155 a default value will be used.
4158 Get DDR timing information from an I2C EEPROM. Common
4159 with pluggable memory modules such as SODIMMs
4162 I2C address of the SPD EEPROM
4164 - CONFIG_SYS_SPD_BUS_NUM
4165 If SPD EEPROM is on an I2C bus other than the first
4166 one, specify here. Note that the value must resolve
4167 to something your driver can deal with.
4169 - CONFIG_SYS_DDR_RAW_TIMING
4170 Get DDR timing information from other than SPD. Common with
4171 soldered DDR chips onboard without SPD. DDR raw timing
4172 parameters are extracted from datasheet and hard-coded into
4173 header files or board specific files.
4175 - CONFIG_FSL_DDR_INTERACTIVE
4176 Enable interactive DDR debugging. See doc/README.fsl-ddr.
4178 - CONFIG_SYS_83XX_DDR_USES_CS0
4179 Only for 83xx systems. If specified, then DDR should
4180 be configured using CS0 and CS1 instead of CS2 and CS3.
4182 - CONFIG_ETHER_ON_FEC[12]
4183 Define to enable FEC[12] on a 8xx series processor.
4185 - CONFIG_FEC[12]_PHY
4186 Define to the hardcoded PHY address which corresponds
4187 to the given FEC; i. e.
4188 #define CONFIG_FEC1_PHY 4
4189 means that the PHY with address 4 is connected to FEC1
4191 When set to -1, means to probe for first available.
4193 - CONFIG_FEC[12]_PHY_NORXERR
4194 The PHY does not have a RXERR line (RMII only).
4195 (so program the FEC to ignore it).
4198 Enable RMII mode for all FECs.
4199 Note that this is a global option, we can't
4200 have one FEC in standard MII mode and another in RMII mode.
4202 - CONFIG_CRC32_VERIFY
4203 Add a verify option to the crc32 command.
4206 => crc32 -v <address> <count> <crc32>
4208 Where address/count indicate a memory area
4209 and crc32 is the correct crc32 which the
4213 Add the "loopw" memory command. This only takes effect if
4214 the memory commands are activated globally (CONFIG_CMD_MEM).
4217 Add the "mdc" and "mwc" memory commands. These are cyclic
4222 This command will print 4 bytes (10,11,12,13) each 500 ms.
4224 => mwc.l 100 12345678 10
4225 This command will write 12345678 to address 100 all 10 ms.
4227 This only takes effect if the memory commands are activated
4228 globally (CONFIG_CMD_MEM).
4230 - CONFIG_SKIP_LOWLEVEL_INIT
4231 [ARM, NDS32, MIPS only] If this variable is defined, then certain
4232 low level initializations (like setting up the memory
4233 controller) are omitted and/or U-Boot does not
4234 relocate itself into RAM.
4236 Normally this variable MUST NOT be defined. The only
4237 exception is when U-Boot is loaded (to RAM) by some
4238 other boot loader or by a debugger which performs
4239 these initializations itself.
4242 Modifies the behaviour of start.S when compiling a loader
4243 that is executed before the actual U-Boot. E.g. when
4244 compiling a NAND SPL.
4247 Modifies the behaviour of start.S when compiling a loader
4248 that is executed after the SPL and before the actual U-Boot.
4249 It is loaded by the SPL.
4251 - CONFIG_SYS_MPC85XX_NO_RESETVEC
4252 Only for 85xx systems. If this variable is specified, the section
4253 .resetvec is not kept and the section .bootpg is placed in the
4254 previous 4k of the .text section.
4256 - CONFIG_ARCH_MAP_SYSMEM
4257 Generally U-Boot (and in particular the md command) uses
4258 effective address. It is therefore not necessary to regard
4259 U-Boot address as virtual addresses that need to be translated
4260 to physical addresses. However, sandbox requires this, since
4261 it maintains its own little RAM buffer which contains all
4262 addressable memory. This option causes some memory accesses
4263 to be mapped through map_sysmem() / unmap_sysmem().
4265 - CONFIG_USE_ARCH_MEMCPY
4266 CONFIG_USE_ARCH_MEMSET
4267 If these options are used a optimized version of memcpy/memset will
4268 be used if available. These functions may be faster under some
4269 conditions but may increase the binary size.
4271 - CONFIG_X86_RESET_VECTOR
4272 If defined, the x86 reset vector code is included. This is not
4273 needed when U-Boot is running from Coreboot.
4276 Defines the MPU clock speed (in MHz).
4278 NOTE : currently only supported on AM335x platforms.
4280 Freescale QE/FMAN Firmware Support:
4281 -----------------------------------
4283 The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
4284 loading of "firmware", which is encoded in the QE firmware binary format.
4285 This firmware often needs to be loaded during U-Boot booting, so macros
4286 are used to identify the storage device (NOR flash, SPI, etc) and the address
4289 - CONFIG_SYS_QE_FMAN_FW_ADDR
4290 The address in the storage device where the firmware is located. The
4291 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
4294 - CONFIG_SYS_QE_FMAN_FW_LENGTH
4295 The maximum possible size of the firmware. The firmware binary format
4296 has a field that specifies the actual size of the firmware, but it
4297 might not be possible to read any part of the firmware unless some
4298 local storage is allocated to hold the entire firmware first.
4300 - CONFIG_SYS_QE_FMAN_FW_IN_NOR
4301 Specifies that QE/FMAN firmware is located in NOR flash, mapped as
4302 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the
4303 virtual address in NOR flash.
4305 - CONFIG_SYS_QE_FMAN_FW_IN_NAND
4306 Specifies that QE/FMAN firmware is located in NAND flash.
4307 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.
4309 - CONFIG_SYS_QE_FMAN_FW_IN_MMC
4310 Specifies that QE/FMAN firmware is located on the primary SD/MMC
4311 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
4313 - CONFIG_SYS_QE_FMAN_FW_IN_SPIFLASH
4314 Specifies that QE/FMAN firmware is located on the primary SPI
4315 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
4317 - CONFIG_SYS_QE_FMAN_FW_IN_REMOTE
4318 Specifies that QE/FMAN firmware is located in the remote (master)
4319 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which
4320 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound
4321 window->master inbound window->master LAW->the ucode address in
4322 master's memory space.
4324 Building the Software:
4325 ======================
4327 Building U-Boot has been tested in several native build environments
4328 and in many different cross environments. Of course we cannot support
4329 all possibly existing versions of cross development tools in all
4330 (potentially obsolete) versions. In case of tool chain problems we
4331 recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
4332 which is extensively used to build and test U-Boot.
4334 If you are not using a native environment, it is assumed that you
4335 have GNU cross compiling tools available in your path. In this case,
4336 you must set the environment variable CROSS_COMPILE in your shell.
4337 Note that no changes to the Makefile or any other source files are
4338 necessary. For example using the ELDK on a 4xx CPU, please enter:
4340 $ CROSS_COMPILE=ppc_4xx-
4341 $ export CROSS_COMPILE
4343 Note: If you wish to generate Windows versions of the utilities in
4344 the tools directory you can use the MinGW toolchain
4345 (http://www.mingw.org). Set your HOST tools to the MinGW
4346 toolchain and execute 'make tools'. For example:
4348 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
4350 Binaries such as tools/mkimage.exe will be created which can
4351 be executed on computers running Windows.
4353 U-Boot is intended to be simple to build. After installing the
4354 sources you must configure U-Boot for one specific board type. This
4359 where "NAME_config" is the name of one of the existing configu-
4360 rations; see boards.cfg for supported names.
4362 Note: for some board special configuration names may exist; check if
4363 additional information is available from the board vendor; for
4364 instance, the TQM823L systems are available without (standard)
4365 or with LCD support. You can select such additional "features"
4366 when choosing the configuration, i. e.
4369 - will configure for a plain TQM823L, i. e. no LCD support
4371 make TQM823L_LCD_config
4372 - will configure for a TQM823L with U-Boot console on LCD
4377 Finally, type "make all", and you should get some working U-Boot
4378 images ready for download to / installation on your system:
4380 - "u-boot.bin" is a raw binary image
4381 - "u-boot" is an image in ELF binary format
4382 - "u-boot.srec" is in Motorola S-Record format
4384 By default the build is performed locally and the objects are saved
4385 in the source directory. One of the two methods can be used to change
4386 this behavior and build U-Boot to some external directory:
4388 1. Add O= to the make command line invocations:
4390 make O=/tmp/build distclean
4391 make O=/tmp/build NAME_config
4392 make O=/tmp/build all
4394 2. Set environment variable BUILD_DIR to point to the desired location:
4396 export BUILD_DIR=/tmp/build
4401 Note that the command line "O=" setting overrides the BUILD_DIR environment
4405 Please be aware that the Makefiles assume you are using GNU make, so
4406 for instance on NetBSD you might need to use "gmake" instead of
4410 If the system board that you have is not listed, then you will need
4411 to port U-Boot to your hardware platform. To do this, follow these
4414 1. Add a new configuration option for your board to the toplevel
4415 "boards.cfg" file, using the existing entries as examples.
4416 Follow the instructions there to keep the boards in order.
4417 2. Create a new directory to hold your board specific code. Add any
4418 files you need. In your board directory, you will need at least
4419 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
4420 3. Create a new configuration file "include/configs/<board>.h" for
4422 3. If you're porting U-Boot to a new CPU, then also create a new
4423 directory to hold your CPU specific code. Add any files you need.
4424 4. Run "make <board>_config" with your new name.
4425 5. Type "make", and you should get a working "u-boot.srec" file
4426 to be installed on your target system.
4427 6. Debug and solve any problems that might arise.
4428 [Of course, this last step is much harder than it sounds.]
4431 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
4432 ==============================================================
4434 If you have modified U-Boot sources (for instance added a new board
4435 or support for new devices, a new CPU, etc.) you are expected to
4436 provide feedback to the other developers. The feedback normally takes
4437 the form of a "patch", i. e. a context diff against a certain (latest
4438 official or latest in the git repository) version of U-Boot sources.
4440 But before you submit such a patch, please verify that your modifi-
4441 cation did not break existing code. At least make sure that *ALL* of
4442 the supported boards compile WITHOUT ANY compiler warnings. To do so,
4443 just run the "MAKEALL" script, which will configure and build U-Boot
4444 for ALL supported system. Be warned, this will take a while. You can
4445 select which (cross) compiler to use by passing a `CROSS_COMPILE'
4446 environment variable to the script, i. e. to use the ELDK cross tools
4449 CROSS_COMPILE=ppc_8xx- MAKEALL
4451 or to build on a native PowerPC system you can type
4453 CROSS_COMPILE=' ' MAKEALL
4455 When using the MAKEALL script, the default behaviour is to build
4456 U-Boot in the source directory. This location can be changed by
4457 setting the BUILD_DIR environment variable. Also, for each target
4458 built, the MAKEALL script saves two log files (<target>.ERR and
4459 <target>.MAKEALL) in the <source dir>/LOG directory. This default
4460 location can be changed by setting the MAKEALL_LOGDIR environment
4461 variable. For example:
4463 export BUILD_DIR=/tmp/build
4464 export MAKEALL_LOGDIR=/tmp/log
4465 CROSS_COMPILE=ppc_8xx- MAKEALL
4467 With the above settings build objects are saved in the /tmp/build,
4468 log files are saved in the /tmp/log and the source tree remains clean
4469 during the whole build process.
4472 See also "U-Boot Porting Guide" below.
4475 Monitor Commands - Overview:
4476 ============================
4478 go - start application at address 'addr'
4479 run - run commands in an environment variable
4480 bootm - boot application image from memory
4481 bootp - boot image via network using BootP/TFTP protocol
4482 bootz - boot zImage from memory
4483 tftpboot- boot image via network using TFTP protocol
4484 and env variables "ipaddr" and "serverip"
4485 (and eventually "gatewayip")
4486 tftpput - upload a file via network using TFTP protocol
4487 rarpboot- boot image via network using RARP/TFTP protocol
4488 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
4489 loads - load S-Record file over serial line
4490 loadb - load binary file over serial line (kermit mode)
4492 mm - memory modify (auto-incrementing)
4493 nm - memory modify (constant address)
4494 mw - memory write (fill)
4496 cmp - memory compare
4497 crc32 - checksum calculation
4498 i2c - I2C sub-system
4499 sspi - SPI utility commands
4500 base - print or set address offset
4501 printenv- print environment variables
4502 setenv - set environment variables
4503 saveenv - save environment variables to persistent storage
4504 protect - enable or disable FLASH write protection
4505 erase - erase FLASH memory
4506 flinfo - print FLASH memory information
4507 nand - NAND memory operations (see doc/README.nand)
4508 bdinfo - print Board Info structure
4509 iminfo - print header information for application image
4510 coninfo - print console devices and informations
4511 ide - IDE sub-system
4512 loop - infinite loop on address range
4513 loopw - infinite write loop on address range
4514 mtest - simple RAM test
4515 icache - enable or disable instruction cache
4516 dcache - enable or disable data cache
4517 reset - Perform RESET of the CPU
4518 echo - echo args to console
4519 version - print monitor version
4520 help - print online help
4521 ? - alias for 'help'
4524 Monitor Commands - Detailed Description:
4525 ========================================
4529 For now: just type "help <command>".
4532 Environment Variables:
4533 ======================
4535 U-Boot supports user configuration using Environment Variables which
4536 can be made persistent by saving to Flash memory.
4538 Environment Variables are set using "setenv", printed using
4539 "printenv", and saved to Flash using "saveenv". Using "setenv"
4540 without a value can be used to delete a variable from the
4541 environment. As long as you don't save the environment you are
4542 working with an in-memory copy. In case the Flash area containing the
4543 environment is erased by accident, a default environment is provided.
4545 Some configuration options can be set using Environment Variables.
4547 List of environment variables (most likely not complete):
4549 baudrate - see CONFIG_BAUDRATE
4551 bootdelay - see CONFIG_BOOTDELAY
4553 bootcmd - see CONFIG_BOOTCOMMAND
4555 bootargs - Boot arguments when booting an RTOS image
4557 bootfile - Name of the image to load with TFTP
4559 bootm_low - Memory range available for image processing in the bootm
4560 command can be restricted. This variable is given as
4561 a hexadecimal number and defines lowest address allowed
4562 for use by the bootm command. See also "bootm_size"
4563 environment variable. Address defined by "bootm_low" is
4564 also the base of the initial memory mapping for the Linux
4565 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
4568 bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
4569 This variable is given as a hexadecimal number and it
4570 defines the size of the memory region starting at base
4571 address bootm_low that is accessible by the Linux kernel
4572 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used
4573 as the default value if it is defined, and bootm_size is
4576 bootm_size - Memory range available for image processing in the bootm
4577 command can be restricted. This variable is given as
4578 a hexadecimal number and defines the size of the region
4579 allowed for use by the bootm command. See also "bootm_low"
4580 environment variable.
4582 updatefile - Location of the software update file on a TFTP server, used
4583 by the automatic software update feature. Please refer to
4584 documentation in doc/README.update for more details.
4586 autoload - if set to "no" (any string beginning with 'n'),
4587 "bootp" will just load perform a lookup of the
4588 configuration from the BOOTP server, but not try to
4589 load any image using TFTP
4591 autostart - if set to "yes", an image loaded using the "bootp",
4592 "rarpboot", "tftpboot" or "diskboot" commands will
4593 be automatically started (by internally calling
4596 If set to "no", a standalone image passed to the
4597 "bootm" command will be copied to the load address
4598 (and eventually uncompressed), but NOT be started.
4599 This can be used to load and uncompress arbitrary
4602 fdt_high - if set this restricts the maximum address that the
4603 flattened device tree will be copied into upon boot.
4604 For example, if you have a system with 1 GB memory
4605 at physical address 0x10000000, while Linux kernel
4606 only recognizes the first 704 MB as low memory, you
4607 may need to set fdt_high as 0x3C000000 to have the
4608 device tree blob be copied to the maximum address
4609 of the 704 MB low memory, so that Linux kernel can
4610 access it during the boot procedure.
4612 If this is set to the special value 0xFFFFFFFF then
4613 the fdt will not be copied at all on boot. For this
4614 to work it must reside in writable memory, have
4615 sufficient padding on the end of it for u-boot to
4616 add the information it needs into it, and the memory
4617 must be accessible by the kernel.
4619 fdtcontroladdr- if set this is the address of the control flattened
4620 device tree used by U-Boot when CONFIG_OF_CONTROL is
4623 i2cfast - (PPC405GP|PPC405EP only)
4624 if set to 'y' configures Linux I2C driver for fast
4625 mode (400kHZ). This environment variable is used in
4626 initialization code. So, for changes to be effective
4627 it must be saved and board must be reset.
4629 initrd_high - restrict positioning of initrd images:
4630 If this variable is not set, initrd images will be
4631 copied to the highest possible address in RAM; this
4632 is usually what you want since it allows for
4633 maximum initrd size. If for some reason you want to
4634 make sure that the initrd image is loaded below the
4635 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
4636 variable to a value of "no" or "off" or "0".
4637 Alternatively, you can set it to a maximum upper
4638 address to use (U-Boot will still check that it
4639 does not overwrite the U-Boot stack and data).
4641 For instance, when you have a system with 16 MB
4642 RAM, and want to reserve 4 MB from use by Linux,
4643 you can do this by adding "mem=12M" to the value of
4644 the "bootargs" variable. However, now you must make
4645 sure that the initrd image is placed in the first
4646 12 MB as well - this can be done with
4648 setenv initrd_high 00c00000
4650 If you set initrd_high to 0xFFFFFFFF, this is an
4651 indication to U-Boot that all addresses are legal
4652 for the Linux kernel, including addresses in flash
4653 memory. In this case U-Boot will NOT COPY the
4654 ramdisk at all. This may be useful to reduce the
4655 boot time on your system, but requires that this
4656 feature is supported by your Linux kernel.
4658 ipaddr - IP address; needed for tftpboot command
4660 loadaddr - Default load address for commands like "bootp",
4661 "rarpboot", "tftpboot", "loadb" or "diskboot"
4663 loads_echo - see CONFIG_LOADS_ECHO
4665 serverip - TFTP server IP address; needed for tftpboot command
4667 bootretry - see CONFIG_BOOT_RETRY_TIME
4669 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
4671 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
4673 ethprime - controls which interface is used first.
4675 ethact - controls which interface is currently active.
4676 For example you can do the following
4678 => setenv ethact FEC
4679 => ping 192.168.0.1 # traffic sent on FEC
4680 => setenv ethact SCC
4681 => ping 10.0.0.1 # traffic sent on SCC
4683 ethrotate - When set to "no" U-Boot does not go through all
4684 available network interfaces.
4685 It just stays at the currently selected interface.
4687 netretry - When set to "no" each network operation will
4688 either succeed or fail without retrying.
4689 When set to "once" the network operation will
4690 fail when all the available network interfaces
4691 are tried once without success.
4692 Useful on scripts which control the retry operation
4695 npe_ucode - set load address for the NPE microcode
4697 silent_linux - If set then linux will be told to boot silently, by
4698 changing the console to be empty. If "yes" it will be
4699 made silent. If "no" it will not be made silent. If
4700 unset, then it will be made silent if the U-Boot console
4703 tftpsrcport - If this is set, the value is used for TFTP's
4706 tftpdstport - If this is set, the value is used for TFTP's UDP
4707 destination port instead of the Well Know Port 69.
4709 tftpblocksize - Block size to use for TFTP transfers; if not set,
4710 we use the TFTP server's default block size
4712 tftptimeout - Retransmission timeout for TFTP packets (in milli-
4713 seconds, minimum value is 1000 = 1 second). Defines
4714 when a packet is considered to be lost so it has to
4715 be retransmitted. The default is 5000 = 5 seconds.
4716 Lowering this value may make downloads succeed
4717 faster in networks with high packet loss rates or
4718 with unreliable TFTP servers.
4720 vlan - When set to a value < 4095 the traffic over
4721 Ethernet is encapsulated/received over 802.1q
4724 The following image location variables contain the location of images
4725 used in booting. The "Image" column gives the role of the image and is
4726 not an environment variable name. The other columns are environment
4727 variable names. "File Name" gives the name of the file on a TFTP
4728 server, "RAM Address" gives the location in RAM the image will be
4729 loaded to, and "Flash Location" gives the image's address in NOR
4730 flash or offset in NAND flash.
4732 *Note* - these variables don't have to be defined for all boards, some
4733 boards currenlty use other variables for these purposes, and some
4734 boards use these variables for other purposes.
4736 Image File Name RAM Address Flash Location
4737 ----- --------- ----------- --------------
4738 u-boot u-boot u-boot_addr_r u-boot_addr
4739 Linux kernel bootfile kernel_addr_r kernel_addr
4740 device tree blob fdtfile fdt_addr_r fdt_addr
4741 ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr
4743 The following environment variables may be used and automatically
4744 updated by the network boot commands ("bootp" and "rarpboot"),
4745 depending the information provided by your boot server:
4747 bootfile - see above
4748 dnsip - IP address of your Domain Name Server
4749 dnsip2 - IP address of your secondary Domain Name Server
4750 gatewayip - IP address of the Gateway (Router) to use
4751 hostname - Target hostname
4753 netmask - Subnet Mask
4754 rootpath - Pathname of the root filesystem on the NFS server
4755 serverip - see above
4758 There are two special Environment Variables:
4760 serial# - contains hardware identification information such
4761 as type string and/or serial number
4762 ethaddr - Ethernet address
4764 These variables can be set only once (usually during manufacturing of
4765 the board). U-Boot refuses to delete or overwrite these variables
4766 once they have been set once.
4769 Further special Environment Variables:
4771 ver - Contains the U-Boot version string as printed
4772 with the "version" command. This variable is
4773 readonly (see CONFIG_VERSION_VARIABLE).
4776 Please note that changes to some configuration parameters may take
4777 only effect after the next boot (yes, that's just like Windoze :-).
4780 Callback functions for environment variables:
4781 ---------------------------------------------
4783 For some environment variables, the behavior of u-boot needs to change
4784 when their values are changed. This functionailty allows functions to
4785 be associated with arbitrary variables. On creation, overwrite, or
4786 deletion, the callback will provide the opportunity for some side
4787 effect to happen or for the change to be rejected.
4789 The callbacks are named and associated with a function using the
4790 U_BOOT_ENV_CALLBACK macro in your board or driver code.
4792 These callbacks are associated with variables in one of two ways. The
4793 static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC
4794 in the board configuration to a string that defines a list of
4795 associations. The list must be in the following format:
4797 entry = variable_name[:callback_name]
4800 If the callback name is not specified, then the callback is deleted.
4801 Spaces are also allowed anywhere in the list.
4803 Callbacks can also be associated by defining the ".callbacks" variable
4804 with the same list format above. Any association in ".callbacks" will
4805 override any association in the static list. You can define
4806 CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the
4807 ".callbacks" envirnoment variable in the default or embedded environment.
4810 Command Line Parsing:
4811 =====================
4813 There are two different command line parsers available with U-Boot:
4814 the old "simple" one, and the much more powerful "hush" shell:
4816 Old, simple command line parser:
4817 --------------------------------
4819 - supports environment variables (through setenv / saveenv commands)
4820 - several commands on one line, separated by ';'
4821 - variable substitution using "... ${name} ..." syntax
4822 - special characters ('$', ';') can be escaped by prefixing with '\',
4824 setenv bootcmd bootm \${address}
4825 - You can also escape text by enclosing in single apostrophes, for example:
4826 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
4831 - similar to Bourne shell, with control structures like
4832 if...then...else...fi, for...do...done; while...do...done,
4833 until...do...done, ...
4834 - supports environment ("global") variables (through setenv / saveenv
4835 commands) and local shell variables (through standard shell syntax
4836 "name=value"); only environment variables can be used with "run"
4842 (1) If a command line (or an environment variable executed by a "run"
4843 command) contains several commands separated by semicolon, and
4844 one of these commands fails, then the remaining commands will be
4847 (2) If you execute several variables with one call to run (i. e.
4848 calling run with a list of variables as arguments), any failing
4849 command will cause "run" to terminate, i. e. the remaining
4850 variables are not executed.
4852 Note for Redundant Ethernet Interfaces:
4853 =======================================
4855 Some boards come with redundant Ethernet interfaces; U-Boot supports
4856 such configurations and is capable of automatic selection of a
4857 "working" interface when needed. MAC assignment works as follows:
4859 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
4860 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
4861 "eth1addr" (=>eth1), "eth2addr", ...
4863 If the network interface stores some valid MAC address (for instance
4864 in SROM), this is used as default address if there is NO correspon-
4865 ding setting in the environment; if the corresponding environment
4866 variable is set, this overrides the settings in the card; that means:
4868 o If the SROM has a valid MAC address, and there is no address in the
4869 environment, the SROM's address is used.
4871 o If there is no valid address in the SROM, and a definition in the
4872 environment exists, then the value from the environment variable is
4875 o If both the SROM and the environment contain a MAC address, and
4876 both addresses are the same, this MAC address is used.
4878 o If both the SROM and the environment contain a MAC address, and the
4879 addresses differ, the value from the environment is used and a
4882 o If neither SROM nor the environment contain a MAC address, an error
4885 If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
4886 will be programmed into hardware as part of the initialization process. This
4887 may be skipped by setting the appropriate 'ethmacskip' environment variable.
4888 The naming convention is as follows:
4889 "ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
4894 U-Boot is capable of booting (and performing other auxiliary operations on)
4895 images in two formats:
4897 New uImage format (FIT)
4898 -----------------------
4900 Flexible and powerful format based on Flattened Image Tree -- FIT (similar
4901 to Flattened Device Tree). It allows the use of images with multiple
4902 components (several kernels, ramdisks, etc.), with contents protected by
4903 SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
4909 Old image format is based on binary files which can be basically anything,
4910 preceded by a special header; see the definitions in include/image.h for
4911 details; basically, the header defines the following image properties:
4913 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
4914 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
4915 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
4916 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
4918 * Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86,
4919 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
4920 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC).
4921 * Compression Type (uncompressed, gzip, bzip2)
4927 The header is marked by a special Magic Number, and both the header
4928 and the data portions of the image are secured against corruption by
4935 Although U-Boot should support any OS or standalone application
4936 easily, the main focus has always been on Linux during the design of
4939 U-Boot includes many features that so far have been part of some
4940 special "boot loader" code within the Linux kernel. Also, any
4941 "initrd" images to be used are no longer part of one big Linux image;
4942 instead, kernel and "initrd" are separate images. This implementation
4943 serves several purposes:
4945 - the same features can be used for other OS or standalone
4946 applications (for instance: using compressed images to reduce the
4947 Flash memory footprint)
4949 - it becomes much easier to port new Linux kernel versions because
4950 lots of low-level, hardware dependent stuff are done by U-Boot
4952 - the same Linux kernel image can now be used with different "initrd"
4953 images; of course this also means that different kernel images can
4954 be run with the same "initrd". This makes testing easier (you don't
4955 have to build a new "zImage.initrd" Linux image when you just
4956 change a file in your "initrd"). Also, a field-upgrade of the
4957 software is easier now.
4963 Porting Linux to U-Boot based systems:
4964 ---------------------------------------
4966 U-Boot cannot save you from doing all the necessary modifications to
4967 configure the Linux device drivers for use with your target hardware
4968 (no, we don't intend to provide a full virtual machine interface to
4971 But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
4973 Just make sure your machine specific header file (for instance
4974 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
4975 Information structure as we define in include/asm-<arch>/u-boot.h,
4976 and make sure that your definition of IMAP_ADDR uses the same value
4977 as your U-Boot configuration in CONFIG_SYS_IMMR.
4980 Configuring the Linux kernel:
4981 -----------------------------
4983 No specific requirements for U-Boot. Make sure you have some root
4984 device (initial ramdisk, NFS) for your target system.
4987 Building a Linux Image:
4988 -----------------------
4990 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
4991 not used. If you use recent kernel source, a new build target
4992 "uImage" will exist which automatically builds an image usable by
4993 U-Boot. Most older kernels also have support for a "pImage" target,
4994 which was introduced for our predecessor project PPCBoot and uses a
4995 100% compatible format.
5004 The "uImage" build target uses a special tool (in 'tools/mkimage') to
5005 encapsulate a compressed Linux kernel image with header information,
5006 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
5008 * build a standard "vmlinux" kernel image (in ELF binary format):
5010 * convert the kernel into a raw binary image:
5012 ${CROSS_COMPILE}-objcopy -O binary \
5013 -R .note -R .comment \
5014 -S vmlinux linux.bin
5016 * compress the binary image:
5020 * package compressed binary image for U-Boot:
5022 mkimage -A ppc -O linux -T kernel -C gzip \
5023 -a 0 -e 0 -n "Linux Kernel Image" \
5024 -d linux.bin.gz uImage
5027 The "mkimage" tool can also be used to create ramdisk images for use
5028 with U-Boot, either separated from the Linux kernel image, or
5029 combined into one file. "mkimage" encapsulates the images with a 64
5030 byte header containing information about target architecture,
5031 operating system, image type, compression method, entry points, time
5032 stamp, CRC32 checksums, etc.
5034 "mkimage" can be called in two ways: to verify existing images and
5035 print the header information, or to build new images.
5037 In the first form (with "-l" option) mkimage lists the information
5038 contained in the header of an existing U-Boot image; this includes
5039 checksum verification:
5041 tools/mkimage -l image
5042 -l ==> list image header information
5044 The second form (with "-d" option) is used to build a U-Boot image
5045 from a "data file" which is used as image payload:
5047 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
5048 -n name -d data_file image
5049 -A ==> set architecture to 'arch'
5050 -O ==> set operating system to 'os'
5051 -T ==> set image type to 'type'
5052 -C ==> set compression type 'comp'
5053 -a ==> set load address to 'addr' (hex)
5054 -e ==> set entry point to 'ep' (hex)
5055 -n ==> set image name to 'name'
5056 -d ==> use image data from 'datafile'
5058 Right now, all Linux kernels for PowerPC systems use the same load
5059 address (0x00000000), but the entry point address depends on the
5062 - 2.2.x kernels have the entry point at 0x0000000C,
5063 - 2.3.x and later kernels have the entry point at 0x00000000.
5065 So a typical call to build a U-Boot image would read:
5067 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
5068 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
5069 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
5070 > examples/uImage.TQM850L
5071 Image Name: 2.4.4 kernel for TQM850L
5072 Created: Wed Jul 19 02:34:59 2000
5073 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5074 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
5075 Load Address: 0x00000000
5076 Entry Point: 0x00000000
5078 To verify the contents of the image (or check for corruption):
5080 -> tools/mkimage -l examples/uImage.TQM850L
5081 Image Name: 2.4.4 kernel for TQM850L
5082 Created: Wed Jul 19 02:34:59 2000
5083 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5084 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
5085 Load Address: 0x00000000
5086 Entry Point: 0x00000000
5088 NOTE: for embedded systems where boot time is critical you can trade
5089 speed for memory and install an UNCOMPRESSED image instead: this
5090 needs more space in Flash, but boots much faster since it does not
5091 need to be uncompressed:
5093 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
5094 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
5095 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
5096 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
5097 > examples/uImage.TQM850L-uncompressed
5098 Image Name: 2.4.4 kernel for TQM850L
5099 Created: Wed Jul 19 02:34:59 2000
5100 Image Type: PowerPC Linux Kernel Image (uncompressed)
5101 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
5102 Load Address: 0x00000000
5103 Entry Point: 0x00000000
5106 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
5107 when your kernel is intended to use an initial ramdisk:
5109 -> tools/mkimage -n 'Simple Ramdisk Image' \
5110 > -A ppc -O linux -T ramdisk -C gzip \
5111 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
5112 Image Name: Simple Ramdisk Image
5113 Created: Wed Jan 12 14:01:50 2000
5114 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5115 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
5116 Load Address: 0x00000000
5117 Entry Point: 0x00000000
5120 Installing a Linux Image:
5121 -------------------------
5123 To downloading a U-Boot image over the serial (console) interface,
5124 you must convert the image to S-Record format:
5126 objcopy -I binary -O srec examples/image examples/image.srec
5128 The 'objcopy' does not understand the information in the U-Boot
5129 image header, so the resulting S-Record file will be relative to
5130 address 0x00000000. To load it to a given address, you need to
5131 specify the target address as 'offset' parameter with the 'loads'
5134 Example: install the image to address 0x40100000 (which on the
5135 TQM8xxL is in the first Flash bank):
5137 => erase 40100000 401FFFFF
5143 ## Ready for S-Record download ...
5144 ~>examples/image.srec
5145 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
5147 15989 15990 15991 15992
5148 [file transfer complete]
5150 ## Start Addr = 0x00000000
5153 You can check the success of the download using the 'iminfo' command;
5154 this includes a checksum verification so you can be sure no data
5155 corruption happened:
5159 ## Checking Image at 40100000 ...
5160 Image Name: 2.2.13 for initrd on TQM850L
5161 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5162 Data Size: 335725 Bytes = 327 kB = 0 MB
5163 Load Address: 00000000
5164 Entry Point: 0000000c
5165 Verifying Checksum ... OK
5171 The "bootm" command is used to boot an application that is stored in
5172 memory (RAM or Flash). In case of a Linux kernel image, the contents
5173 of the "bootargs" environment variable is passed to the kernel as
5174 parameters. You can check and modify this variable using the
5175 "printenv" and "setenv" commands:
5178 => printenv bootargs
5179 bootargs=root=/dev/ram
5181 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5183 => printenv bootargs
5184 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5187 ## Booting Linux kernel at 40020000 ...
5188 Image Name: 2.2.13 for NFS on TQM850L
5189 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5190 Data Size: 381681 Bytes = 372 kB = 0 MB
5191 Load Address: 00000000
5192 Entry Point: 0000000c
5193 Verifying Checksum ... OK
5194 Uncompressing Kernel Image ... OK
5195 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
5196 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5197 time_init: decrementer frequency = 187500000/60
5198 Calibrating delay loop... 49.77 BogoMIPS
5199 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
5202 If you want to boot a Linux kernel with initial RAM disk, you pass
5203 the memory addresses of both the kernel and the initrd image (PPBCOOT
5204 format!) to the "bootm" command:
5206 => imi 40100000 40200000
5208 ## Checking Image at 40100000 ...
5209 Image Name: 2.2.13 for initrd on TQM850L
5210 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5211 Data Size: 335725 Bytes = 327 kB = 0 MB
5212 Load Address: 00000000
5213 Entry Point: 0000000c
5214 Verifying Checksum ... OK
5216 ## Checking Image at 40200000 ...
5217 Image Name: Simple Ramdisk Image
5218 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5219 Data Size: 566530 Bytes = 553 kB = 0 MB
5220 Load Address: 00000000
5221 Entry Point: 00000000
5222 Verifying Checksum ... OK
5224 => bootm 40100000 40200000
5225 ## Booting Linux kernel at 40100000 ...
5226 Image Name: 2.2.13 for initrd on TQM850L
5227 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5228 Data Size: 335725 Bytes = 327 kB = 0 MB
5229 Load Address: 00000000
5230 Entry Point: 0000000c
5231 Verifying Checksum ... OK
5232 Uncompressing Kernel Image ... OK
5233 ## Loading RAMDisk Image at 40200000 ...
5234 Image Name: Simple Ramdisk Image
5235 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5236 Data Size: 566530 Bytes = 553 kB = 0 MB
5237 Load Address: 00000000
5238 Entry Point: 00000000
5239 Verifying Checksum ... OK
5240 Loading Ramdisk ... OK
5241 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
5242 Boot arguments: root=/dev/ram
5243 time_init: decrementer frequency = 187500000/60
5244 Calibrating delay loop... 49.77 BogoMIPS
5246 RAMDISK: Compressed image found at block 0
5247 VFS: Mounted root (ext2 filesystem).
5251 Boot Linux and pass a flat device tree:
5254 First, U-Boot must be compiled with the appropriate defines. See the section
5255 titled "Linux Kernel Interface" above for a more in depth explanation. The
5256 following is an example of how to start a kernel and pass an updated
5262 oft=oftrees/mpc8540ads.dtb
5263 => tftp $oftaddr $oft
5264 Speed: 1000, full duplex
5266 TFTP from server 192.168.1.1; our IP address is 192.168.1.101
5267 Filename 'oftrees/mpc8540ads.dtb'.
5268 Load address: 0x300000
5271 Bytes transferred = 4106 (100a hex)
5272 => tftp $loadaddr $bootfile
5273 Speed: 1000, full duplex
5275 TFTP from server 192.168.1.1; our IP address is 192.168.1.2
5277 Load address: 0x200000
5278 Loading:############
5280 Bytes transferred = 1029407 (fb51f hex)
5285 => bootm $loadaddr - $oftaddr
5286 ## Booting image at 00200000 ...
5287 Image Name: Linux-2.6.17-dirty
5288 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5289 Data Size: 1029343 Bytes = 1005.2 kB
5290 Load Address: 00000000
5291 Entry Point: 00000000
5292 Verifying Checksum ... OK
5293 Uncompressing Kernel Image ... OK
5294 Booting using flat device tree at 0x300000
5295 Using MPC85xx ADS machine description
5296 Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
5300 More About U-Boot Image Types:
5301 ------------------------------
5303 U-Boot supports the following image types:
5305 "Standalone Programs" are directly runnable in the environment
5306 provided by U-Boot; it is expected that (if they behave
5307 well) you can continue to work in U-Boot after return from
5308 the Standalone Program.
5309 "OS Kernel Images" are usually images of some Embedded OS which
5310 will take over control completely. Usually these programs
5311 will install their own set of exception handlers, device
5312 drivers, set up the MMU, etc. - this means, that you cannot
5313 expect to re-enter U-Boot except by resetting the CPU.
5314 "RAMDisk Images" are more or less just data blocks, and their
5315 parameters (address, size) are passed to an OS kernel that is
5317 "Multi-File Images" contain several images, typically an OS
5318 (Linux) kernel image and one or more data images like
5319 RAMDisks. This construct is useful for instance when you want
5320 to boot over the network using BOOTP etc., where the boot
5321 server provides just a single image file, but you want to get
5322 for instance an OS kernel and a RAMDisk image.
5324 "Multi-File Images" start with a list of image sizes, each
5325 image size (in bytes) specified by an "uint32_t" in network
5326 byte order. This list is terminated by an "(uint32_t)0".
5327 Immediately after the terminating 0 follow the images, one by
5328 one, all aligned on "uint32_t" boundaries (size rounded up to
5329 a multiple of 4 bytes).
5331 "Firmware Images" are binary images containing firmware (like
5332 U-Boot or FPGA images) which usually will be programmed to
5335 "Script files" are command sequences that will be executed by
5336 U-Boot's command interpreter; this feature is especially
5337 useful when you configure U-Boot to use a real shell (hush)
5338 as command interpreter.
5340 Booting the Linux zImage:
5341 -------------------------
5343 On some platforms, it's possible to boot Linux zImage. This is done
5344 using the "bootz" command. The syntax of "bootz" command is the same
5345 as the syntax of "bootm" command.
5347 Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply
5348 kernel with raw initrd images. The syntax is slightly different, the
5349 address of the initrd must be augmented by it's size, in the following
5350 format: "<initrd addres>:<initrd size>".
5356 One of the features of U-Boot is that you can dynamically load and
5357 run "standalone" applications, which can use some resources of
5358 U-Boot like console I/O functions or interrupt services.
5360 Two simple examples are included with the sources:
5365 'examples/hello_world.c' contains a small "Hello World" Demo
5366 application; it is automatically compiled when you build U-Boot.
5367 It's configured to run at address 0x00040004, so you can play with it
5371 ## Ready for S-Record download ...
5372 ~>examples/hello_world.srec
5373 1 2 3 4 5 6 7 8 9 10 11 ...
5374 [file transfer complete]
5376 ## Start Addr = 0x00040004
5378 => go 40004 Hello World! This is a test.
5379 ## Starting application at 0x00040004 ...
5390 Hit any key to exit ...
5392 ## Application terminated, rc = 0x0
5394 Another example, which demonstrates how to register a CPM interrupt
5395 handler with the U-Boot code, can be found in 'examples/timer.c'.
5396 Here, a CPM timer is set up to generate an interrupt every second.
5397 The interrupt service routine is trivial, just printing a '.'
5398 character, but this is just a demo program. The application can be
5399 controlled by the following keys:
5401 ? - print current values og the CPM Timer registers
5402 b - enable interrupts and start timer
5403 e - stop timer and disable interrupts
5404 q - quit application
5407 ## Ready for S-Record download ...
5408 ~>examples/timer.srec
5409 1 2 3 4 5 6 7 8 9 10 11 ...
5410 [file transfer complete]
5412 ## Start Addr = 0x00040004
5415 ## Starting application at 0x00040004 ...
5418 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
5421 [q, b, e, ?] Set interval 1000000 us
5424 [q, b, e, ?] ........
5425 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
5428 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
5431 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
5434 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
5436 [q, b, e, ?] ...Stopping timer
5438 [q, b, e, ?] ## Application terminated, rc = 0x0
5444 Over time, many people have reported problems when trying to use the
5445 "minicom" terminal emulation program for serial download. I (wd)
5446 consider minicom to be broken, and recommend not to use it. Under
5447 Unix, I recommend to use C-Kermit for general purpose use (and
5448 especially for kermit binary protocol download ("loadb" command), and
5449 use "cu" for S-Record download ("loads" command). See
5450 http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3.
5451 for help with kermit.
5454 Nevertheless, if you absolutely want to use it try adding this
5455 configuration to your "File transfer protocols" section:
5457 Name Program Name U/D FullScr IO-Red. Multi
5458 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
5459 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
5465 Starting at version 0.9.2, U-Boot supports NetBSD both as host
5466 (build U-Boot) and target system (boots NetBSD/mpc8xx).
5468 Building requires a cross environment; it is known to work on
5469 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
5470 need gmake since the Makefiles are not compatible with BSD make).
5471 Note that the cross-powerpc package does not install include files;
5472 attempting to build U-Boot will fail because <machine/ansi.h> is
5473 missing. This file has to be installed and patched manually:
5475 # cd /usr/pkg/cross/powerpc-netbsd/include
5477 # ln -s powerpc machine
5478 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
5479 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
5481 Native builds *don't* work due to incompatibilities between native
5482 and U-Boot include files.
5484 Booting assumes that (the first part of) the image booted is a
5485 stage-2 loader which in turn loads and then invokes the kernel
5486 proper. Loader sources will eventually appear in the NetBSD source
5487 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
5488 meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
5491 Implementation Internals:
5492 =========================
5494 The following is not intended to be a complete description of every
5495 implementation detail. However, it should help to understand the
5496 inner workings of U-Boot and make it easier to port it to custom
5500 Initial Stack, Global Data:
5501 ---------------------------
5503 The implementation of U-Boot is complicated by the fact that U-Boot
5504 starts running out of ROM (flash memory), usually without access to
5505 system RAM (because the memory controller is not initialized yet).
5506 This means that we don't have writable Data or BSS segments, and BSS
5507 is not initialized as zero. To be able to get a C environment working
5508 at all, we have to allocate at least a minimal stack. Implementation
5509 options for this are defined and restricted by the CPU used: Some CPU
5510 models provide on-chip memory (like the IMMR area on MPC8xx and
5511 MPC826x processors), on others (parts of) the data cache can be
5512 locked as (mis-) used as memory, etc.
5514 Chris Hallinan posted a good summary of these issues to the
5515 U-Boot mailing list:
5517 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
5518 From: "Chris Hallinan" <clh@net1plus.com>
5519 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
5522 Correct me if I'm wrong, folks, but the way I understand it
5523 is this: Using DCACHE as initial RAM for Stack, etc, does not
5524 require any physical RAM backing up the cache. The cleverness
5525 is that the cache is being used as a temporary supply of
5526 necessary storage before the SDRAM controller is setup. It's
5527 beyond the scope of this list to explain the details, but you
5528 can see how this works by studying the cache architecture and
5529 operation in the architecture and processor-specific manuals.
5531 OCM is On Chip Memory, which I believe the 405GP has 4K. It
5532 is another option for the system designer to use as an
5533 initial stack/RAM area prior to SDRAM being available. Either
5534 option should work for you. Using CS 4 should be fine if your
5535 board designers haven't used it for something that would
5536 cause you grief during the initial boot! It is frequently not
5539 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
5540 with your processor/board/system design. The default value
5541 you will find in any recent u-boot distribution in
5542 walnut.h should work for you. I'd set it to a value larger
5543 than your SDRAM module. If you have a 64MB SDRAM module, set
5544 it above 400_0000. Just make sure your board has no resources
5545 that are supposed to respond to that address! That code in
5546 start.S has been around a while and should work as is when
5547 you get the config right.
5552 It is essential to remember this, since it has some impact on the C
5553 code for the initialization procedures:
5555 * Initialized global data (data segment) is read-only. Do not attempt
5558 * Do not use any uninitialized global data (or implicitely initialized
5559 as zero data - BSS segment) at all - this is undefined, initiali-
5560 zation is performed later (when relocating to RAM).
5562 * Stack space is very limited. Avoid big data buffers or things like
5565 Having only the stack as writable memory limits means we cannot use
5566 normal global data to share information beween the code. But it
5567 turned out that the implementation of U-Boot can be greatly
5568 simplified by making a global data structure (gd_t) available to all
5569 functions. We could pass a pointer to this data as argument to _all_
5570 functions, but this would bloat the code. Instead we use a feature of
5571 the GCC compiler (Global Register Variables) to share the data: we
5572 place a pointer (gd) to the global data into a register which we
5573 reserve for this purpose.
5575 When choosing a register for such a purpose we are restricted by the
5576 relevant (E)ABI specifications for the current architecture, and by
5577 GCC's implementation.
5579 For PowerPC, the following registers have specific use:
5581 R2: reserved for system use
5582 R3-R4: parameter passing and return values
5583 R5-R10: parameter passing
5584 R13: small data area pointer
5588 (U-Boot also uses R12 as internal GOT pointer. r12
5589 is a volatile register so r12 needs to be reset when
5590 going back and forth between asm and C)
5592 ==> U-Boot will use R2 to hold a pointer to the global data
5594 Note: on PPC, we could use a static initializer (since the
5595 address of the global data structure is known at compile time),
5596 but it turned out that reserving a register results in somewhat
5597 smaller code - although the code savings are not that big (on
5598 average for all boards 752 bytes for the whole U-Boot image,
5599 624 text + 127 data).
5601 On Blackfin, the normal C ABI (except for P3) is followed as documented here:
5602 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface
5604 ==> U-Boot will use P3 to hold a pointer to the global data
5606 On ARM, the following registers are used:
5608 R0: function argument word/integer result
5609 R1-R3: function argument word
5610 R9: platform specific
5611 R10: stack limit (used only if stack checking is enabled)
5612 R11: argument (frame) pointer
5613 R12: temporary workspace
5616 R15: program counter
5618 ==> U-Boot will use R9 to hold a pointer to the global data
5620 Note: on ARM, only R_ARM_RELATIVE relocations are supported.
5622 On Nios II, the ABI is documented here:
5623 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
5625 ==> U-Boot will use gp to hold a pointer to the global data
5627 Note: on Nios II, we give "-G0" option to gcc and don't use gp
5628 to access small data sections, so gp is free.
5630 On NDS32, the following registers are used:
5632 R0-R1: argument/return
5634 R15: temporary register for assembler
5635 R16: trampoline register
5636 R28: frame pointer (FP)
5637 R29: global pointer (GP)
5638 R30: link register (LP)
5639 R31: stack pointer (SP)
5640 PC: program counter (PC)
5642 ==> U-Boot will use R10 to hold a pointer to the global data
5644 NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
5645 or current versions of GCC may "optimize" the code too much.
5650 U-Boot runs in system state and uses physical addresses, i.e. the
5651 MMU is not used either for address mapping nor for memory protection.
5653 The available memory is mapped to fixed addresses using the memory
5654 controller. In this process, a contiguous block is formed for each
5655 memory type (Flash, SDRAM, SRAM), even when it consists of several
5656 physical memory banks.
5658 U-Boot is installed in the first 128 kB of the first Flash bank (on
5659 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
5660 booting and sizing and initializing DRAM, the code relocates itself
5661 to the upper end of DRAM. Immediately below the U-Boot code some
5662 memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
5663 configuration setting]. Below that, a structure with global Board
5664 Info data is placed, followed by the stack (growing downward).
5666 Additionally, some exception handler code is copied to the low 8 kB
5667 of DRAM (0x00000000 ... 0x00001FFF).
5669 So a typical memory configuration with 16 MB of DRAM could look like
5672 0x0000 0000 Exception Vector code
5675 0x0000 2000 Free for Application Use
5681 0x00FB FF20 Monitor Stack (Growing downward)
5682 0x00FB FFAC Board Info Data and permanent copy of global data
5683 0x00FC 0000 Malloc Arena
5686 0x00FE 0000 RAM Copy of Monitor Code
5687 ... eventually: LCD or video framebuffer
5688 ... eventually: pRAM (Protected RAM - unchanged by reset)
5689 0x00FF FFFF [End of RAM]
5692 System Initialization:
5693 ----------------------
5695 In the reset configuration, U-Boot starts at the reset entry point
5696 (on most PowerPC systems at address 0x00000100). Because of the reset
5697 configuration for CS0# this is a mirror of the onboard Flash memory.
5698 To be able to re-map memory U-Boot then jumps to its link address.
5699 To be able to implement the initialization code in C, a (small!)
5700 initial stack is set up in the internal Dual Ported RAM (in case CPUs
5701 which provide such a feature like MPC8xx or MPC8260), or in a locked
5702 part of the data cache. After that, U-Boot initializes the CPU core,
5703 the caches and the SIU.
5705 Next, all (potentially) available memory banks are mapped using a
5706 preliminary mapping. For example, we put them on 512 MB boundaries
5707 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
5708 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
5709 programmed for SDRAM access. Using the temporary configuration, a
5710 simple memory test is run that determines the size of the SDRAM
5713 When there is more than one SDRAM bank, and the banks are of
5714 different size, the largest is mapped first. For equal size, the first
5715 bank (CS2#) is mapped first. The first mapping is always for address
5716 0x00000000, with any additional banks following immediately to create
5717 contiguous memory starting from 0.
5719 Then, the monitor installs itself at the upper end of the SDRAM area
5720 and allocates memory for use by malloc() and for the global Board
5721 Info data; also, the exception vector code is copied to the low RAM
5722 pages, and the final stack is set up.
5724 Only after this relocation will you have a "normal" C environment;
5725 until that you are restricted in several ways, mostly because you are
5726 running from ROM, and because the code will have to be relocated to a
5730 U-Boot Porting Guide:
5731 ----------------------
5733 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
5737 int main(int argc, char *argv[])
5739 sighandler_t no_more_time;
5741 signal(SIGALRM, no_more_time);
5742 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
5744 if (available_money > available_manpower) {
5745 Pay consultant to port U-Boot;
5749 Download latest U-Boot source;
5751 Subscribe to u-boot mailing list;
5754 email("Hi, I am new to U-Boot, how do I get started?");
5757 Read the README file in the top level directory;
5758 Read http://www.denx.de/twiki/bin/view/DULG/Manual;
5759 Read applicable doc/*.README;
5760 Read the source, Luke;
5761 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
5764 if (available_money > toLocalCurrency ($2500))
5767 Add a lot of aggravation and time;
5769 if (a similar board exists) { /* hopefully... */
5770 cp -a board/<similar> board/<myboard>
5771 cp include/configs/<similar>.h include/configs/<myboard>.h
5773 Create your own board support subdirectory;
5774 Create your own board include/configs/<myboard>.h file;
5776 Edit new board/<myboard> files
5777 Edit new include/configs/<myboard>.h
5782 Add / modify source code;
5786 email("Hi, I am having problems...");
5788 Send patch file to the U-Boot email list;
5789 if (reasonable critiques)
5790 Incorporate improvements from email list code review;
5792 Defend code as written;
5798 void no_more_time (int sig)
5807 All contributions to U-Boot should conform to the Linux kernel
5808 coding style; see the file "Documentation/CodingStyle" and the script
5809 "scripts/Lindent" in your Linux kernel source directory.
5811 Source files originating from a different project (for example the
5812 MTD subsystem) are generally exempt from these guidelines and are not
5813 reformated to ease subsequent migration to newer versions of those
5816 Please note that U-Boot is implemented in C (and to some small parts in
5817 Assembler); no C++ is used, so please do not use C++ style comments (//)
5820 Please also stick to the following formatting rules:
5821 - remove any trailing white space
5822 - use TAB characters for indentation and vertical alignment, not spaces
5823 - make sure NOT to use DOS '\r\n' line feeds
5824 - do not add more than 2 consecutive empty lines to source files
5825 - do not add trailing empty lines to source files
5827 Submissions which do not conform to the standards may be returned
5828 with a request to reformat the changes.
5834 Since the number of patches for U-Boot is growing, we need to
5835 establish some rules. Submissions which do not conform to these rules
5836 may be rejected, even when they contain important and valuable stuff.
5838 Please see http://www.denx.de/wiki/U-Boot/Patches for details.
5840 Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
5841 see http://lists.denx.de/mailman/listinfo/u-boot
5843 When you send a patch, please include the following information with
5846 * For bug fixes: a description of the bug and how your patch fixes
5847 this bug. Please try to include a way of demonstrating that the
5848 patch actually fixes something.
5850 * For new features: a description of the feature and your
5853 * A CHANGELOG entry as plaintext (separate from the patch)
5855 * For major contributions, your entry to the CREDITS file
5857 * When you add support for a new board, don't forget to add a
5858 maintainer e-mail address to the boards.cfg file, too.
5860 * If your patch adds new configuration options, don't forget to
5861 document these in the README file.
5863 * The patch itself. If you are using git (which is *strongly*
5864 recommended) you can easily generate the patch using the
5865 "git format-patch". If you then use "git send-email" to send it to
5866 the U-Boot mailing list, you will avoid most of the common problems
5867 with some other mail clients.
5869 If you cannot use git, use "diff -purN OLD NEW". If your version of
5870 diff does not support these options, then get the latest version of
5873 The current directory when running this command shall be the parent
5874 directory of the U-Boot source tree (i. e. please make sure that
5875 your patch includes sufficient directory information for the
5878 We prefer patches as plain text. MIME attachments are discouraged,
5879 and compressed attachments must not be used.
5881 * If one logical set of modifications affects or creates several
5882 files, all these changes shall be submitted in a SINGLE patch file.
5884 * Changesets that contain different, unrelated modifications shall be
5885 submitted as SEPARATE patches, one patch per changeset.
5890 * Before sending the patch, run the MAKEALL script on your patched
5891 source tree and make sure that no errors or warnings are reported
5892 for any of the boards.
5894 * Keep your modifications to the necessary minimum: A patch
5895 containing several unrelated changes or arbitrary reformats will be
5896 returned with a request to re-formatting / split it.
5898 * If you modify existing code, make sure that your new code does not
5899 add to the memory footprint of the code ;-) Small is beautiful!
5900 When adding new features, these should compile conditionally only
5901 (using #ifdef), and the resulting code with the new feature
5902 disabled must not need more memory than the old code without your
5905 * Remember that there is a size limit of 100 kB per message on the
5906 u-boot mailing list. Bigger patches will be moderated. If they are
5907 reasonable and not too big, they will be acknowledged. But patches
5908 bigger than the size limit should be avoided.
projects / platform / kernel / u-boot.git / blob