2 # (C) Copyright 2000 - 2011
3 # Wolfgang Denk, DENX Software Engineering, wd@denx.de.
5 # See file CREDITS for list of people who contributed to this
8 # This program is free software; you can redistribute it and/or
9 # modify it under the terms of the GNU General Public License as
10 # published by the Free Software Foundation; either version 2 of
11 # the License, or (at your option) any later version.
13 # This program is distributed in the hope that it will be useful,
14 # but WITHOUT ANY WARRANTY; without even the implied warranty of
15 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 # GNU General Public License for more details.
18 # You should have received a copy of the GNU General Public License
19 # along with this program; if not, write to the Free Software
20 # Foundation, Inc., 59 Temple Place, Suite 330, Boston,
27 This directory contains the source code for U-Boot, a boot loader for
28 Embedded boards based on PowerPC, ARM, MIPS and several other
29 processors, which can be installed in a boot ROM and used to
30 initialize and test the hardware or to download and run application
33 The development of U-Boot is closely related to Linux: some parts of
34 the source code originate in the Linux source tree, we have some
35 header files in common, and special provision has been made to
36 support booting of Linux images.
38 Some attention has been paid to make this software easily
39 configurable and extendable. For instance, all monitor commands are
40 implemented with the same call interface, so that it's very easy to
41 add new commands. Also, instead of permanently adding rarely used
42 code (for instance hardware test utilities) to the monitor, you can
43 load and run it dynamically.
49 In general, all boards for which a configuration option exists in the
50 Makefile have been tested to some extent and can be considered
51 "working". In fact, many of them are used in production systems.
53 In case of problems see the CHANGELOG and CREDITS files to find out
54 who contributed the specific port. The MAINTAINERS file lists board
61 In case you have questions about, problems with or contributions for
62 U-Boot you should send a message to the U-Boot mailing list at
63 <u-boot@lists.denx.de>. There is also an archive of previous traffic
64 on the mailing list - please search the archive before asking FAQ's.
65 Please see http://lists.denx.de/pipermail/u-boot and
66 http://dir.gmane.org/gmane.comp.boot-loaders.u-boot
69 Where to get source code:
70 =========================
72 The U-Boot source code is maintained in the git repository at
73 git://www.denx.de/git/u-boot.git ; you can browse it online at
74 http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary
76 The "snapshot" links on this page allow you to download tarballs of
77 any version you might be interested in. Official releases are also
78 available for FTP download from the ftp://ftp.denx.de/pub/u-boot/
81 Pre-built (and tested) images are available from
82 ftp://ftp.denx.de/pub/u-boot/images/
88 - start from 8xxrom sources
89 - create PPCBoot project (http://sourceforge.net/projects/ppcboot)
91 - make it easier to add custom boards
92 - make it possible to add other [PowerPC] CPUs
93 - extend functions, especially:
94 * Provide extended interface to Linux boot loader
97 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot
98 - create ARMBoot project (http://sourceforge.net/projects/armboot)
99 - add other CPU families (starting with ARM)
100 - create U-Boot project (http://sourceforge.net/projects/u-boot)
101 - current project page: see http://www.denx.de/wiki/U-Boot
107 The "official" name of this project is "Das U-Boot". The spelling
108 "U-Boot" shall be used in all written text (documentation, comments
109 in source files etc.). Example:
111 This is the README file for the U-Boot project.
113 File names etc. shall be based on the string "u-boot". Examples:
115 include/asm-ppc/u-boot.h
117 #include <asm/u-boot.h>
119 Variable names, preprocessor constants etc. shall be either based on
120 the string "u_boot" or on "U_BOOT". Example:
122 U_BOOT_VERSION u_boot_logo
123 IH_OS_U_BOOT u_boot_hush_start
129 Starting with the release in October 2008, the names of the releases
130 were changed from numerical release numbers without deeper meaning
131 into a time stamp based numbering. Regular releases are identified by
132 names consisting of the calendar year and month of the release date.
133 Additional fields (if present) indicate release candidates or bug fix
134 releases in "stable" maintenance trees.
137 U-Boot v2009.11 - Release November 2009
138 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree
139 U-Boot v2010.09-rc1 - Release candiate 1 for September 2010 release
145 /arch Architecture specific files
146 /arm Files generic to ARM architecture
147 /cpu CPU specific files
148 /arm720t Files specific to ARM 720 CPUs
149 /arm920t Files specific to ARM 920 CPUs
150 /at91rm9200 Files specific to Atmel AT91RM9200 CPU
151 /imx Files specific to Freescale MC9328 i.MX CPUs
152 /s3c24x0 Files specific to Samsung S3C24X0 CPUs
153 /arm925t Files specific to ARM 925 CPUs
154 /arm926ejs Files specific to ARM 926 CPUs
155 /arm1136 Files specific to ARM 1136 CPUs
156 /ixp Files specific to Intel XScale IXP CPUs
157 /pxa Files specific to Intel XScale PXA CPUs
158 /s3c44b0 Files specific to Samsung S3C44B0 CPUs
159 /sa1100 Files specific to Intel StrongARM SA1100 CPUs
160 /lib Architecture specific library files
161 /avr32 Files generic to AVR32 architecture
162 /cpu CPU specific files
163 /lib Architecture specific library files
164 /blackfin Files generic to Analog Devices Blackfin architecture
165 /cpu CPU specific files
166 /lib Architecture specific library files
167 /x86 Files generic to x86 architecture
168 /cpu CPU specific files
169 /lib Architecture specific library files
170 /m68k Files generic to m68k architecture
171 /cpu CPU specific files
172 /mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs
173 /mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs
174 /mcf532x Files specific to Freescale ColdFire MCF5329 CPUs
175 /mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs
176 /mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs
177 /lib Architecture specific library files
178 /microblaze Files generic to microblaze architecture
179 /cpu CPU specific files
180 /lib Architecture specific library files
181 /mips Files generic to MIPS architecture
182 /cpu CPU specific files
183 /lib Architecture specific library files
184 /nios2 Files generic to Altera NIOS2 architecture
185 /cpu CPU specific files
186 /lib Architecture specific library files
187 /powerpc Files generic to PowerPC architecture
188 /cpu CPU specific files
189 /74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs
190 /mpc5xx Files specific to Freescale MPC5xx CPUs
191 /mpc5xxx Files specific to Freescale MPC5xxx CPUs
192 /mpc8xx Files specific to Freescale MPC8xx CPUs
193 /mpc8220 Files specific to Freescale MPC8220 CPUs
194 /mpc824x Files specific to Freescale MPC824x CPUs
195 /mpc8260 Files specific to Freescale MPC8260 CPUs
196 /mpc85xx Files specific to Freescale MPC85xx CPUs
197 /ppc4xx Files specific to AMCC PowerPC 4xx CPUs
198 /lib Architecture specific library files
199 /sh Files generic to SH architecture
200 /cpu CPU specific files
201 /sh2 Files specific to sh2 CPUs
202 /sh3 Files specific to sh3 CPUs
203 /sh4 Files specific to sh4 CPUs
204 /lib Architecture specific library files
205 /sparc Files generic to SPARC architecture
206 /cpu CPU specific files
207 /leon2 Files specific to Gaisler LEON2 SPARC CPU
208 /leon3 Files specific to Gaisler LEON3 SPARC CPU
209 /lib Architecture specific library files
210 /api Machine/arch independent API for external apps
211 /board Board dependent files
212 /common Misc architecture independent functions
213 /disk Code for disk drive partition handling
214 /doc Documentation (don't expect too much)
215 /drivers Commonly used device drivers
216 /examples Example code for standalone applications, etc.
217 /fs Filesystem code (cramfs, ext2, jffs2, etc.)
218 /include Header Files
219 /lib Files generic to all architectures
220 /libfdt Library files to support flattened device trees
221 /lzma Library files to support LZMA decompression
222 /lzo Library files to support LZO decompression
224 /post Power On Self Test
225 /rtc Real Time Clock drivers
226 /tools Tools to build S-Record or U-Boot images, etc.
228 Software Configuration:
229 =======================
231 Configuration is usually done using C preprocessor defines; the
232 rationale behind that is to avoid dead code whenever possible.
234 There are two classes of configuration variables:
236 * Configuration _OPTIONS_:
237 These are selectable by the user and have names beginning with
240 * Configuration _SETTINGS_:
241 These depend on the hardware etc. and should not be meddled with if
242 you don't know what you're doing; they have names beginning with
245 Later we will add a configuration tool - probably similar to or even
246 identical to what's used for the Linux kernel. Right now, we have to
247 do the configuration by hand, which means creating some symbolic
248 links and editing some configuration files. We use the TQM8xxL boards
252 Selection of Processor Architecture and Board Type:
253 ---------------------------------------------------
255 For all supported boards there are ready-to-use default
256 configurations available; just type "make <board_name>_config".
258 Example: For a TQM823L module type:
263 For the Cogent platform, you need to specify the CPU type as well;
264 e.g. "make cogent_mpc8xx_config". And also configure the cogent
265 directory according to the instructions in cogent/README.
268 Configuration Options:
269 ----------------------
271 Configuration depends on the combination of board and CPU type; all
272 such information is kept in a configuration file
273 "include/configs/<board_name>.h".
275 Example: For a TQM823L module, all configuration settings are in
276 "include/configs/TQM823L.h".
279 Many of the options are named exactly as the corresponding Linux
280 kernel configuration options. The intention is to make it easier to
281 build a config tool - later.
284 The following options need to be configured:
286 - CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
288 - Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
290 - CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined)
291 Define exactly one, e.g. CONFIG_ATSTK1002
293 - CPU Module Type: (if CONFIG_COGENT is defined)
294 Define exactly one of
296 --- FIXME --- not tested yet:
297 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
298 CONFIG_CMA287_23, CONFIG_CMA287_50
300 - Motherboard Type: (if CONFIG_COGENT is defined)
301 Define exactly one of
302 CONFIG_CMA101, CONFIG_CMA102
304 - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
305 Define one or more of
308 - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
309 Define one or more of
310 CONFIG_LCD_HEARTBEAT - update a character position on
311 the LCD display every second with
314 - Board flavour: (if CONFIG_MPC8260ADS is defined)
317 CONFIG_SYS_8260ADS - original MPC8260ADS
318 CONFIG_SYS_8266ADS - MPC8266ADS
319 CONFIG_SYS_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR
320 CONFIG_SYS_8272ADS - MPC8272ADS
322 - Marvell Family Member
323 CONFIG_SYS_MVFS - define it if you want to enable
324 multiple fs option at one time
325 for marvell soc family
327 - MPC824X Family Member (if CONFIG_MPC824X is defined)
328 Define exactly one of
329 CONFIG_MPC8240, CONFIG_MPC8245
331 - 8xx CPU Options: (if using an MPC8xx CPU)
332 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if
333 get_gclk_freq() cannot work
334 e.g. if there is no 32KHz
335 reference PIT/RTC clock
336 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK
339 - 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
340 CONFIG_SYS_8xx_CPUCLK_MIN
341 CONFIG_SYS_8xx_CPUCLK_MAX
342 CONFIG_8xx_CPUCLK_DEFAULT
343 See doc/README.MPC866
345 CONFIG_SYS_MEASURE_CPUCLK
347 Define this to measure the actual CPU clock instead
348 of relying on the correctness of the configured
349 values. Mostly useful for board bringup to make sure
350 the PLL is locked at the intended frequency. Note
351 that this requires a (stable) reference clock (32 kHz
352 RTC clock or CONFIG_SYS_8XX_XIN)
354 CONFIG_SYS_DELAYED_ICACHE
356 Define this option if you want to enable the
357 ICache only when Code runs from RAM.
360 CONFIG_SYS_FSL_TBCLK_DIV
362 Defines the core time base clock divider ratio compared to the
363 system clock. On most PQ3 devices this is 8, on newer QorIQ
364 devices it can be 16 or 32. The ratio varies from SoC to Soc.
366 CONFIG_SYS_FSL_PCIE_COMPAT
368 Defines the string to utilize when trying to match PCIe device
369 tree nodes for the given platform.
371 - Intel Monahans options:
372 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO
374 Defines the Monahans run mode to oscillator
375 ratio. Valid values are 8, 16, 24, 31. The core
376 frequency is this value multiplied by 13 MHz.
378 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO
380 Defines the Monahans turbo mode to oscillator
381 ratio. Valid values are 1 (default if undefined) and
382 2. The core frequency as calculated above is multiplied
385 - Linux Kernel Interface:
388 U-Boot stores all clock information in Hz
389 internally. For binary compatibility with older Linux
390 kernels (which expect the clocks passed in the
391 bd_info data to be in MHz) the environment variable
392 "clocks_in_mhz" can be defined so that U-Boot
393 converts clock data to MHZ before passing it to the
395 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
396 "clocks_in_mhz=1" is automatically included in the
399 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
401 When transferring memsize parameter to linux, some versions
402 expect it to be in bytes, others in MB.
403 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
407 New kernel versions are expecting firmware settings to be
408 passed using flattened device trees (based on open firmware
412 * New libfdt-based support
413 * Adds the "fdt" command
414 * The bootm command automatically updates the fdt
416 OF_CPU - The proper name of the cpus node (only required for
417 MPC512X and MPC5xxx based boards).
418 OF_SOC - The proper name of the soc node (only required for
419 MPC512X and MPC5xxx based boards).
420 OF_TBCLK - The timebase frequency.
421 OF_STDOUT_PATH - The path to the console device
423 boards with QUICC Engines require OF_QE to set UCC MAC
426 CONFIG_OF_BOARD_SETUP
428 Board code has addition modification that it wants to make
429 to the flat device tree before handing it off to the kernel
433 This define fills in the correct boot CPU in the boot
434 param header, the default value is zero if undefined.
438 U-Boot can detect if an IDE device is present or not.
439 If not, and this new config option is activated, U-Boot
440 removes the ATA node from the DTS before booting Linux,
441 so the Linux IDE driver does not probe the device and
442 crash. This is needed for buggy hardware (uc101) where
443 no pull down resistor is connected to the signal IDE5V_DD7.
445 - vxWorks boot parameters:
447 bootvx constructs a valid bootline using the following
448 environments variables: bootfile, ipaddr, serverip, hostname.
449 It loads the vxWorks image pointed bootfile.
451 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name
452 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address
453 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server
454 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters
456 CONFIG_SYS_VXWORKS_ADD_PARAMS
458 Add it at the end of the bootline. E.g "u=username pw=secret"
460 Note: If a "bootargs" environment is defined, it will overwride
461 the defaults discussed just above.
466 Define this if you want support for Amba PrimeCell PL010 UARTs.
470 Define this if you want support for Amba PrimeCell PL011 UARTs.
474 If you have Amba PrimeCell PL011 UARTs, set this variable to
475 the clock speed of the UARTs.
479 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
480 define this to a list of base addresses for each (supported)
481 port. See e.g. include/configs/versatile.h
483 CONFIG_PL011_SERIAL_RLCR
485 Some vendor versions of PL011 serial ports (e.g. ST-Ericsson U8500)
486 have separate receive and transmit line control registers. Set
487 this variable to initialize the extra register.
489 CONFIG_PL011_SERIAL_FLUSH_ON_INIT
491 On some platforms (e.g. U8500) U-Boot is loaded by a second stage
492 boot loader that has already initialized the UART. Define this
493 variable to flush the UART at init time.
497 Depending on board, define exactly one serial port
498 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
499 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
500 console by defining CONFIG_8xx_CONS_NONE
502 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
503 port routines must be defined elsewhere
504 (i.e. serial_init(), serial_getc(), ...)
507 Enables console device for a color framebuffer. Needs following
508 defines (cf. smiLynxEM, i8042, board/eltec/bab7xx)
509 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
511 VIDEO_HW_RECTFILL graphic chip supports
514 VIDEO_HW_BITBLT graphic chip supports
515 bit-blit (cf. smiLynxEM)
516 VIDEO_VISIBLE_COLS visible pixel columns
518 VIDEO_VISIBLE_ROWS visible pixel rows
519 VIDEO_PIXEL_SIZE bytes per pixel
520 VIDEO_DATA_FORMAT graphic data format
521 (0-5, cf. cfb_console.c)
522 VIDEO_FB_ADRS framebuffer address
523 VIDEO_KBD_INIT_FCT keyboard int fct
524 (i.e. i8042_kbd_init())
525 VIDEO_TSTC_FCT test char fct
527 VIDEO_GETC_FCT get char fct
529 CONFIG_CONSOLE_CURSOR cursor drawing on/off
530 (requires blink timer
532 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
533 CONFIG_CONSOLE_TIME display time/date info in
535 (requires CONFIG_CMD_DATE)
536 CONFIG_VIDEO_LOGO display Linux logo in
538 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
539 linux_logo.h for logo.
540 Requires CONFIG_VIDEO_LOGO
541 CONFIG_CONSOLE_EXTRA_INFO
542 additional board info beside
545 When CONFIG_CFB_CONSOLE is defined, video console is
546 default i/o. Serial console can be forced with
547 environment 'console=serial'.
549 When CONFIG_SILENT_CONSOLE is defined, all console
550 messages (by U-Boot and Linux!) can be silenced with
551 the "silent" environment variable. See
552 doc/README.silent for more information.
555 CONFIG_BAUDRATE - in bps
556 Select one of the baudrates listed in
557 CONFIG_SYS_BAUDRATE_TABLE, see below.
558 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale
560 - Console Rx buffer length
561 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define
562 the maximum receive buffer length for the SMC.
563 This option is actual only for 82xx and 8xx possible.
564 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE
565 must be defined, to setup the maximum idle timeout for
568 - Boot Delay: CONFIG_BOOTDELAY - in seconds
569 Delay before automatically booting the default image;
570 set to -1 to disable autoboot.
572 See doc/README.autoboot for these options that
573 work with CONFIG_BOOTDELAY. None are required.
574 CONFIG_BOOT_RETRY_TIME
575 CONFIG_BOOT_RETRY_MIN
576 CONFIG_AUTOBOOT_KEYED
577 CONFIG_AUTOBOOT_PROMPT
578 CONFIG_AUTOBOOT_DELAY_STR
579 CONFIG_AUTOBOOT_STOP_STR
580 CONFIG_AUTOBOOT_DELAY_STR2
581 CONFIG_AUTOBOOT_STOP_STR2
582 CONFIG_ZERO_BOOTDELAY_CHECK
583 CONFIG_RESET_TO_RETRY
587 Only needed when CONFIG_BOOTDELAY is enabled;
588 define a command string that is automatically executed
589 when no character is read on the console interface
590 within "Boot Delay" after reset.
593 This can be used to pass arguments to the bootm
594 command. The value of CONFIG_BOOTARGS goes into the
595 environment value "bootargs".
597 CONFIG_RAMBOOT and CONFIG_NFSBOOT
598 The value of these goes into the environment as
599 "ramboot" and "nfsboot" respectively, and can be used
600 as a convenience, when switching between booting from
606 When this option is #defined, the existence of the
607 environment variable "preboot" will be checked
608 immediately before starting the CONFIG_BOOTDELAY
609 countdown and/or running the auto-boot command resp.
610 entering interactive mode.
612 This feature is especially useful when "preboot" is
613 automatically generated or modified. For an example
614 see the LWMON board specific code: here "preboot" is
615 modified when the user holds down a certain
616 combination of keys on the (special) keyboard when
619 - Serial Download Echo Mode:
621 If defined to 1, all characters received during a
622 serial download (using the "loads" command) are
623 echoed back. This might be needed by some terminal
624 emulations (like "cu"), but may as well just take
625 time on others. This setting #define's the initial
626 value of the "loads_echo" environment variable.
628 - Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
630 Select one of the baudrates listed in
631 CONFIG_SYS_BAUDRATE_TABLE, see below.
634 Monitor commands can be included or excluded
635 from the build by using the #include files
636 "config_cmd_all.h" and #undef'ing unwanted
637 commands, or using "config_cmd_default.h"
638 and augmenting with additional #define's
641 The default command configuration includes all commands
642 except those marked below with a "*".
644 CONFIG_CMD_ASKENV * ask for env variable
645 CONFIG_CMD_BDI bdinfo
646 CONFIG_CMD_BEDBUG * Include BedBug Debugger
647 CONFIG_CMD_BMP * BMP support
648 CONFIG_CMD_BSP * Board specific commands
649 CONFIG_CMD_BOOTD bootd
650 CONFIG_CMD_CACHE * icache, dcache
651 CONFIG_CMD_CONSOLE coninfo
652 CONFIG_CMD_CRC32 * crc32
653 CONFIG_CMD_DATE * support for RTC, date/time...
654 CONFIG_CMD_DHCP * DHCP support
655 CONFIG_CMD_DIAG * Diagnostics
656 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands
657 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command
658 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd
659 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command
660 CONFIG_CMD_DTT * Digital Therm and Thermostat
661 CONFIG_CMD_ECHO echo arguments
662 CONFIG_CMD_EDITENV edit env variable
663 CONFIG_CMD_EEPROM * EEPROM read/write support
664 CONFIG_CMD_ELF * bootelf, bootvx
665 CONFIG_CMD_EXPORTENV * export the environment
666 CONFIG_CMD_SAVEENV saveenv
667 CONFIG_CMD_FDC * Floppy Disk Support
668 CONFIG_CMD_FAT * FAT partition support
669 CONFIG_CMD_FDOS * Dos diskette Support
670 CONFIG_CMD_FLASH flinfo, erase, protect
671 CONFIG_CMD_FPGA FPGA device initialization support
672 CONFIG_CMD_GO * the 'go' command (exec code)
673 CONFIG_CMD_GREPENV * search environment
674 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control
675 CONFIG_CMD_I2C * I2C serial bus support
676 CONFIG_CMD_IDE * IDE harddisk support
677 CONFIG_CMD_IMI iminfo
678 CONFIG_CMD_IMLS List all found images
679 CONFIG_CMD_IMMAP * IMMR dump support
680 CONFIG_CMD_IMPORTENV * import an environment
681 CONFIG_CMD_IRQ * irqinfo
682 CONFIG_CMD_ITEST Integer/string test of 2 values
683 CONFIG_CMD_JFFS2 * JFFS2 Support
684 CONFIG_CMD_KGDB * kgdb
685 CONFIG_CMD_LDRINFO ldrinfo (display Blackfin loader)
686 CONFIG_CMD_LOADB loadb
687 CONFIG_CMD_LOADS loads
688 CONFIG_CMD_MD5SUM print md5 message digest
689 (requires CONFIG_CMD_MEMORY and CONFIG_MD5)
690 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
692 CONFIG_CMD_MISC Misc functions like sleep etc
693 CONFIG_CMD_MMC * MMC memory mapped support
694 CONFIG_CMD_MII * MII utility commands
695 CONFIG_CMD_MTDPARTS * MTD partition support
696 CONFIG_CMD_NAND * NAND support
697 CONFIG_CMD_NET bootp, tftpboot, rarpboot
698 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands
699 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command
700 CONFIG_CMD_PCI * pciinfo
701 CONFIG_CMD_PCMCIA * PCMCIA support
702 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network
704 CONFIG_CMD_PORTIO * Port I/O
705 CONFIG_CMD_REGINFO * Register dump
706 CONFIG_CMD_RUN run command in env variable
707 CONFIG_CMD_SAVES * save S record dump
708 CONFIG_CMD_SCSI * SCSI Support
709 CONFIG_CMD_SDRAM * print SDRAM configuration information
710 (requires CONFIG_CMD_I2C)
711 CONFIG_CMD_SETGETDCR Support for DCR Register access
713 CONFIG_CMD_SHA1SUM print sha1 memory digest
714 (requires CONFIG_CMD_MEMORY)
715 CONFIG_CMD_SOURCE "source" command Support
716 CONFIG_CMD_SPI * SPI serial bus support
717 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode
718 CONFIG_CMD_USB * USB support
719 CONFIG_CMD_VFD * VFD support (TRAB)
720 CONFIG_CMD_CDP * Cisco Discover Protocol support
721 CONFIG_CMD_FSL * Microblaze FSL support
724 EXAMPLE: If you want all functions except of network
725 support you can write:
727 #include "config_cmd_all.h"
728 #undef CONFIG_CMD_NET
731 fdt (flattened device tree) command: CONFIG_OF_LIBFDT
733 Note: Don't enable the "icache" and "dcache" commands
734 (configuration option CONFIG_CMD_CACHE) unless you know
735 what you (and your U-Boot users) are doing. Data
736 cache cannot be enabled on systems like the 8xx or
737 8260 (where accesses to the IMMR region must be
738 uncached), and it cannot be disabled on all other
739 systems where we (mis-) use the data cache to hold an
740 initial stack and some data.
743 XXX - this list needs to get updated!
747 If this variable is defined, it enables watchdog
748 support for the SoC. There must be support in the SoC
749 specific code for a watchdog. For the 8xx and 8260
750 CPUs, the SIU Watchdog feature is enabled in the SYPCR
751 register. When supported for a specific SoC is
752 available, then no further board specific code should
756 When using a watchdog circuitry external to the used
757 SoC, then define this variable and provide board
758 specific code for the "hw_watchdog_reset" function.
761 CONFIG_VERSION_VARIABLE
762 If this variable is defined, an environment variable
763 named "ver" is created by U-Boot showing the U-Boot
764 version as printed by the "version" command.
765 This variable is readonly.
769 When CONFIG_CMD_DATE is selected, the type of the RTC
770 has to be selected, too. Define exactly one of the
773 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
774 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
775 CONFIG_RTC_MC13783 - use MC13783 RTC
776 CONFIG_RTC_MC146818 - use MC146818 RTC
777 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
778 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
779 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
780 CONFIG_RTC_DS164x - use Dallas DS164x RTC
781 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
782 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
783 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
784 CONFIG_SYS_RV3029_TCR - enable trickle charger on
787 Note that if the RTC uses I2C, then the I2C interface
788 must also be configured. See I2C Support, below.
791 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
792 CONFIG_PCA953X_INFO - enable pca953x info command
794 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
795 chip-ngpio pairs that tell the PCA953X driver the number of
796 pins supported by a particular chip.
798 Note that if the GPIO device uses I2C, then the I2C interface
799 must also be configured. See I2C Support, below.
803 When CONFIG_TIMESTAMP is selected, the timestamp
804 (date and time) of an image is printed by image
805 commands like bootm or iminfo. This option is
806 automatically enabled when you select CONFIG_CMD_DATE .
809 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION
810 and/or CONFIG_ISO_PARTITION and/or CONFIG_EFI_PARTITION
812 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or
813 CONFIG_CMD_SCSI) you must configure support for at
814 least one partition type as well.
817 CONFIG_IDE_RESET_ROUTINE - this is defined in several
818 board configurations files but used nowhere!
820 CONFIG_IDE_RESET - is this is defined, IDE Reset will
821 be performed by calling the function
822 ide_set_reset(int reset)
823 which has to be defined in a board specific file
828 Set this to enable ATAPI support.
833 Set this to enable support for disks larger than 137GB
834 Also look at CONFIG_SYS_64BIT_LBA.
835 Whithout these , LBA48 support uses 32bit variables and will 'only'
836 support disks up to 2.1TB.
838 CONFIG_SYS_64BIT_LBA:
839 When enabled, makes the IDE subsystem use 64bit sector addresses.
843 At the moment only there is only support for the
844 SYM53C8XX SCSI controller; define
845 CONFIG_SCSI_SYM53C8XX to enable it.
847 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
848 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
849 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
850 maximum numbers of LUNs, SCSI ID's and target
852 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
854 - NETWORK Support (PCI):
856 Support for Intel 8254x gigabit chips.
858 CONFIG_E1000_FALLBACK_MAC
859 default MAC for empty EEPROM after production.
862 Support for Intel 82557/82559/82559ER chips.
863 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
864 write routine for first time initialisation.
867 Support for Digital 2114x chips.
868 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
869 modem chip initialisation (KS8761/QS6611).
872 Support for National dp83815 chips.
875 Support for National dp8382[01] gigabit chips.
877 - NETWORK Support (other):
879 CONFIG_DRIVER_AT91EMAC
880 Support for AT91RM9200 EMAC.
883 Define this to use reduced MII inteface
885 CONFIG_DRIVER_AT91EMAC_QUIET
886 If this defined, the driver is quiet.
887 The driver doen't show link status messages.
889 CONFIG_DRIVER_LAN91C96
890 Support for SMSC's LAN91C96 chips.
893 Define this to hold the physical address
894 of the LAN91C96's I/O space
896 CONFIG_LAN91C96_USE_32_BIT
897 Define this to enable 32 bit addressing
899 CONFIG_DRIVER_SMC91111
900 Support for SMSC's LAN91C111 chip
903 Define this to hold the physical address
904 of the device (I/O space)
906 CONFIG_SMC_USE_32_BIT
907 Define this if data bus is 32 bits
909 CONFIG_SMC_USE_IOFUNCS
910 Define this to use i/o functions instead of macros
911 (some hardware wont work with macros)
914 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
916 CONFIG_FTGMAC100_EGIGA
917 Define this to use GE link update with gigabit PHY.
918 Define this if FTGMAC100 is connected to gigabit PHY.
919 If your system has 10/100 PHY only, it might not occur
920 wrong behavior. Because PHY usually return timeout or
921 useless data when polling gigabit status and gigabit
922 control registers. This behavior won't affect the
923 correctnessof 10/100 link speed update.
926 Support for SMSC's LAN911x and LAN921x chips
929 Define this to hold the physical address
930 of the device (I/O space)
932 CONFIG_SMC911X_32_BIT
933 Define this if data bus is 32 bits
935 CONFIG_SMC911X_16_BIT
936 Define this if data bus is 16 bits. If your processor
937 automatically converts one 32 bit word to two 16 bit
938 words you may also try CONFIG_SMC911X_32_BIT.
941 Support for Renesas on-chip Ethernet controller
943 CONFIG_SH_ETHER_USE_PORT
944 Define the number of ports to be used
946 CONFIG_SH_ETHER_PHY_ADDR
947 Define the ETH PHY's address
949 CONFIG_SH_ETHER_CACHE_WRITEBACK
950 If this option is set, the driver enables cache flush.
953 At the moment only the UHCI host controller is
954 supported (PIP405, MIP405, MPC5200); define
955 CONFIG_USB_UHCI to enable it.
956 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
957 and define CONFIG_USB_STORAGE to enable the USB
960 Supported are USB Keyboards and USB Floppy drives
962 MPC5200 USB requires additional defines:
964 for 528 MHz Clock: 0x0001bbbb
968 for differential drivers: 0x00001000
969 for single ended drivers: 0x00005000
970 for differential drivers on PSC3: 0x00000100
971 for single ended drivers on PSC3: 0x00004100
972 CONFIG_SYS_USB_EVENT_POLL
973 May be defined to allow interrupt polling
974 instead of using asynchronous interrupts
977 Define the below if you wish to use the USB console.
978 Once firmware is rebuilt from a serial console issue the
979 command "setenv stdin usbtty; setenv stdout usbtty" and
980 attach your USB cable. The Unix command "dmesg" should print
981 it has found a new device. The environment variable usbtty
982 can be set to gserial or cdc_acm to enable your device to
983 appear to a USB host as a Linux gserial device or a
984 Common Device Class Abstract Control Model serial device.
985 If you select usbtty = gserial you should be able to enumerate
987 # modprobe usbserial vendor=0xVendorID product=0xProductID
988 else if using cdc_acm, simply setting the environment
989 variable usbtty to be cdc_acm should suffice. The following
990 might be defined in YourBoardName.h
993 Define this to build a UDC device
996 Define this to have a tty type of device available to
997 talk to the UDC device
999 CONFIG_SYS_CONSOLE_IS_IN_ENV
1000 Define this if you want stdin, stdout &/or stderr to
1004 CONFIG_SYS_USB_EXTC_CLK 0xBLAH
1005 Derive USB clock from external clock "blah"
1006 - CONFIG_SYS_USB_EXTC_CLK 0x02
1008 CONFIG_SYS_USB_BRG_CLK 0xBLAH
1009 Derive USB clock from brgclk
1010 - CONFIG_SYS_USB_BRG_CLK 0x04
1012 If you have a USB-IF assigned VendorID then you may wish to
1013 define your own vendor specific values either in BoardName.h
1014 or directly in usbd_vendor_info.h. If you don't define
1015 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
1016 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
1017 should pretend to be a Linux device to it's target host.
1019 CONFIG_USBD_MANUFACTURER
1020 Define this string as the name of your company for
1021 - CONFIG_USBD_MANUFACTURER "my company"
1023 CONFIG_USBD_PRODUCT_NAME
1024 Define this string as the name of your product
1025 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
1027 CONFIG_USBD_VENDORID
1028 Define this as your assigned Vendor ID from the USB
1029 Implementors Forum. This *must* be a genuine Vendor ID
1030 to avoid polluting the USB namespace.
1031 - CONFIG_USBD_VENDORID 0xFFFF
1033 CONFIG_USBD_PRODUCTID
1034 Define this as the unique Product ID
1036 - CONFIG_USBD_PRODUCTID 0xFFFF
1040 The MMC controller on the Intel PXA is supported. To
1041 enable this define CONFIG_MMC. The MMC can be
1042 accessed from the boot prompt by mapping the device
1043 to physical memory similar to flash. Command line is
1044 enabled with CONFIG_CMD_MMC. The MMC driver also works with
1045 the FAT fs. This is enabled with CONFIG_CMD_FAT.
1047 - Journaling Flash filesystem support:
1048 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
1049 CONFIG_JFFS2_NAND_DEV
1050 Define these for a default partition on a NAND device
1052 CONFIG_SYS_JFFS2_FIRST_SECTOR,
1053 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
1054 Define these for a default partition on a NOR device
1056 CONFIG_SYS_JFFS_CUSTOM_PART
1057 Define this to create an own partition. You have to provide a
1058 function struct part_info* jffs2_part_info(int part_num)
1060 If you define only one JFFS2 partition you may also want to
1061 #define CONFIG_SYS_JFFS_SINGLE_PART 1
1062 to disable the command chpart. This is the default when you
1063 have not defined a custom partition
1068 Define this to enable standard (PC-Style) keyboard
1072 Standard PC keyboard driver with US (is default) and
1073 GERMAN key layout (switch via environment 'keymap=de') support.
1074 Export function i8042_kbd_init, i8042_tstc and i8042_getc
1075 for cfb_console. Supports cursor blinking.
1080 Define this to enable video support (for output to
1083 CONFIG_VIDEO_CT69000
1085 Enable Chips & Technologies 69000 Video chip
1087 CONFIG_VIDEO_SMI_LYNXEM
1088 Enable Silicon Motion SMI 712/710/810 Video chip. The
1089 video output is selected via environment 'videoout'
1090 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
1093 For the CT69000 and SMI_LYNXEM drivers, videomode is
1094 selected via environment 'videomode'. Two different ways
1096 - "videomode=num" 'num' is a standard LiLo mode numbers.
1097 Following standard modes are supported (* is default):
1099 Colors 640x480 800x600 1024x768 1152x864 1280x1024
1100 -------------+---------------------------------------------
1101 8 bits | 0x301* 0x303 0x305 0x161 0x307
1102 15 bits | 0x310 0x313 0x316 0x162 0x319
1103 16 bits | 0x311 0x314 0x317 0x163 0x31A
1104 24 bits | 0x312 0x315 0x318 ? 0x31B
1105 -------------+---------------------------------------------
1106 (i.e. setenv videomode 317; saveenv; reset;)
1108 - "videomode=bootargs" all the video parameters are parsed
1109 from the bootargs. (See drivers/video/videomodes.c)
1112 CONFIG_VIDEO_SED13806
1113 Enable Epson SED13806 driver. This driver supports 8bpp
1114 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
1115 or CONFIG_VIDEO_SED13806_16BPP
1118 Enable the Freescale DIU video driver. Reference boards for
1119 SOCs that have a DIU should define this macro to enable DIU
1120 support, and should also define these other macros:
1126 CONFIG_VIDEO_SW_CURSOR
1127 CONFIG_VGA_AS_SINGLE_DEVICE
1129 CONFIG_VIDEO_BMP_LOGO
1131 The DIU driver will look for the 'video-mode' environment
1132 variable, and if defined, enable the DIU as a console during
1133 boot. See the documentation file README.video for a
1134 description of this variable.
1139 Define this to enable a custom keyboard support.
1140 This simply calls drv_keyboard_init() which must be
1141 defined in your board-specific files.
1142 The only board using this so far is RBC823.
1144 - LCD Support: CONFIG_LCD
1146 Define this to enable LCD support (for output to LCD
1147 display); also select one of the supported displays
1148 by defining one of these:
1152 HITACHI TX09D70VM1CCA, 3.5", 240x320.
1154 CONFIG_NEC_NL6448AC33:
1156 NEC NL6448AC33-18. Active, color, single scan.
1158 CONFIG_NEC_NL6448BC20
1160 NEC NL6448BC20-08. 6.5", 640x480.
1161 Active, color, single scan.
1163 CONFIG_NEC_NL6448BC33_54
1165 NEC NL6448BC33-54. 10.4", 640x480.
1166 Active, color, single scan.
1170 Sharp 320x240. Active, color, single scan.
1171 It isn't 16x9, and I am not sure what it is.
1173 CONFIG_SHARP_LQ64D341
1175 Sharp LQ64D341 display, 640x480.
1176 Active, color, single scan.
1180 HLD1045 display, 640x480.
1181 Active, color, single scan.
1185 Optrex CBL50840-2 NF-FW 99 22 M5
1187 Hitachi LMG6912RPFC-00T
1191 320x240. Black & white.
1193 Normally display is black on white background; define
1194 CONFIG_SYS_WHITE_ON_BLACK to get it inverted.
1196 - Splash Screen Support: CONFIG_SPLASH_SCREEN
1198 If this option is set, the environment is checked for
1199 a variable "splashimage". If found, the usual display
1200 of logo, copyright and system information on the LCD
1201 is suppressed and the BMP image at the address
1202 specified in "splashimage" is loaded instead. The
1203 console is redirected to the "nulldev", too. This
1204 allows for a "silent" boot where a splash screen is
1205 loaded very quickly after power-on.
1207 CONFIG_SPLASH_SCREEN_ALIGN
1209 If this option is set the splash image can be freely positioned
1210 on the screen. Environment variable "splashpos" specifies the
1211 position as "x,y". If a positive number is given it is used as
1212 number of pixel from left/top. If a negative number is given it
1213 is used as number of pixel from right/bottom. You can also
1214 specify 'm' for centering the image.
1217 setenv splashpos m,m
1218 => image at center of screen
1220 setenv splashpos 30,20
1221 => image at x = 30 and y = 20
1223 setenv splashpos -10,m
1224 => vertically centered image
1225 at x = dspWidth - bmpWidth - 9
1227 - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
1229 If this option is set, additionally to standard BMP
1230 images, gzipped BMP images can be displayed via the
1231 splashscreen support or the bmp command.
1233 - Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
1235 If this option is set, 8-bit RLE compressed BMP images
1236 can be displayed via the splashscreen support or the
1239 - Compression support:
1242 If this option is set, support for bzip2 compressed
1243 images is included. If not, only uncompressed and gzip
1244 compressed images are supported.
1246 NOTE: the bzip2 algorithm requires a lot of RAM, so
1247 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
1252 If this option is set, support for lzma compressed
1255 Note: The LZMA algorithm adds between 2 and 4KB of code and it
1256 requires an amount of dynamic memory that is given by the
1259 (1846 + 768 << (lc + lp)) * sizeof(uint16)
1261 Where lc and lp stand for, respectively, Literal context bits
1262 and Literal pos bits.
1264 This value is upper-bounded by 14MB in the worst case. Anyway,
1265 for a ~4MB large kernel image, we have lc=3 and lp=0 for a
1266 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is
1267 a very small buffer.
1269 Use the lzmainfo tool to determinate the lc and lp values and
1270 then calculate the amount of needed dynamic memory (ensuring
1271 the appropriate CONFIG_SYS_MALLOC_LEN value).
1276 The address of PHY on MII bus.
1278 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1280 The clock frequency of the MII bus
1284 If this option is set, support for speed/duplex
1285 detection of gigabit PHY is included.
1287 CONFIG_PHY_RESET_DELAY
1289 Some PHY like Intel LXT971A need extra delay after
1290 reset before any MII register access is possible.
1291 For such PHY, set this option to the usec delay
1292 required. (minimum 300usec for LXT971A)
1294 CONFIG_PHY_CMD_DELAY (ppc4xx)
1296 Some PHY like Intel LXT971A need extra delay after
1297 command issued before MII status register can be read
1307 Define a default value for Ethernet address to use
1308 for the respective Ethernet interface, in case this
1309 is not determined automatically.
1314 Define a default value for the IP address to use for
1315 the default Ethernet interface, in case this is not
1316 determined through e.g. bootp.
1318 - Server IP address:
1321 Defines a default value for the IP address of a TFTP
1322 server to contact when using the "tftboot" command.
1324 CONFIG_KEEP_SERVERADDR
1326 Keeps the server's MAC address, in the env 'serveraddr'
1327 for passing to bootargs (like Linux's netconsole option)
1329 - Multicast TFTP Mode:
1332 Defines whether you want to support multicast TFTP as per
1333 rfc-2090; for example to work with atftp. Lets lots of targets
1334 tftp down the same boot image concurrently. Note: the Ethernet
1335 driver in use must provide a function: mcast() to join/leave a
1338 - BOOTP Recovery Mode:
1339 CONFIG_BOOTP_RANDOM_DELAY
1341 If you have many targets in a network that try to
1342 boot using BOOTP, you may want to avoid that all
1343 systems send out BOOTP requests at precisely the same
1344 moment (which would happen for instance at recovery
1345 from a power failure, when all systems will try to
1346 boot, thus flooding the BOOTP server. Defining
1347 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1348 inserted before sending out BOOTP requests. The
1349 following delays are inserted then:
1351 1st BOOTP request: delay 0 ... 1 sec
1352 2nd BOOTP request: delay 0 ... 2 sec
1353 3rd BOOTP request: delay 0 ... 4 sec
1355 BOOTP requests: delay 0 ... 8 sec
1357 - DHCP Advanced Options:
1358 You can fine tune the DHCP functionality by defining
1359 CONFIG_BOOTP_* symbols:
1361 CONFIG_BOOTP_SUBNETMASK
1362 CONFIG_BOOTP_GATEWAY
1363 CONFIG_BOOTP_HOSTNAME
1364 CONFIG_BOOTP_NISDOMAIN
1365 CONFIG_BOOTP_BOOTPATH
1366 CONFIG_BOOTP_BOOTFILESIZE
1369 CONFIG_BOOTP_SEND_HOSTNAME
1370 CONFIG_BOOTP_NTPSERVER
1371 CONFIG_BOOTP_TIMEOFFSET
1372 CONFIG_BOOTP_VENDOREX
1374 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
1375 environment variable, not the BOOTP server.
1377 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
1378 serverip from a DHCP server, it is possible that more
1379 than one DNS serverip is offered to the client.
1380 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1381 serverip will be stored in the additional environment
1382 variable "dnsip2". The first DNS serverip is always
1383 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
1386 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1387 to do a dynamic update of a DNS server. To do this, they
1388 need the hostname of the DHCP requester.
1389 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
1390 of the "hostname" environment variable is passed as
1391 option 12 to the DHCP server.
1393 CONFIG_BOOTP_DHCP_REQUEST_DELAY
1395 A 32bit value in microseconds for a delay between
1396 receiving a "DHCP Offer" and sending the "DHCP Request".
1397 This fixes a problem with certain DHCP servers that don't
1398 respond 100% of the time to a "DHCP request". E.g. On an
1399 AT91RM9200 processor running at 180MHz, this delay needed
1400 to be *at least* 15,000 usec before a Windows Server 2003
1401 DHCP server would reply 100% of the time. I recommend at
1402 least 50,000 usec to be safe. The alternative is to hope
1403 that one of the retries will be successful but note that
1404 the DHCP timeout and retry process takes a longer than
1408 CONFIG_CDP_DEVICE_ID
1410 The device id used in CDP trigger frames.
1412 CONFIG_CDP_DEVICE_ID_PREFIX
1414 A two character string which is prefixed to the MAC address
1419 A printf format string which contains the ascii name of
1420 the port. Normally is set to "eth%d" which sets
1421 eth0 for the first Ethernet, eth1 for the second etc.
1423 CONFIG_CDP_CAPABILITIES
1425 A 32bit integer which indicates the device capabilities;
1426 0x00000010 for a normal host which does not forwards.
1430 An ascii string containing the version of the software.
1434 An ascii string containing the name of the platform.
1438 A 32bit integer sent on the trigger.
1440 CONFIG_CDP_POWER_CONSUMPTION
1442 A 16bit integer containing the power consumption of the
1443 device in .1 of milliwatts.
1445 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1447 A byte containing the id of the VLAN.
1449 - Status LED: CONFIG_STATUS_LED
1451 Several configurations allow to display the current
1452 status using a LED. For instance, the LED will blink
1453 fast while running U-Boot code, stop blinking as
1454 soon as a reply to a BOOTP request was received, and
1455 start blinking slow once the Linux kernel is running
1456 (supported by a status LED driver in the Linux
1457 kernel). Defining CONFIG_STATUS_LED enables this
1460 - CAN Support: CONFIG_CAN_DRIVER
1462 Defining CONFIG_CAN_DRIVER enables CAN driver support
1463 on those systems that support this (optional)
1464 feature, like the TQM8xxL modules.
1466 - I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C
1468 These enable I2C serial bus commands. Defining either of
1469 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will
1470 include the appropriate I2C driver for the selected CPU.
1472 This will allow you to use i2c commands at the u-boot
1473 command line (as long as you set CONFIG_CMD_I2C in
1474 CONFIG_COMMANDS) and communicate with i2c based realtime
1475 clock chips. See common/cmd_i2c.c for a description of the
1476 command line interface.
1478 CONFIG_HARD_I2C selects a hardware I2C controller.
1480 CONFIG_SOFT_I2C configures u-boot to use a software (aka
1481 bit-banging) driver instead of CPM or similar hardware
1484 There are several other quantities that must also be
1485 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C.
1487 In both cases you will need to define CONFIG_SYS_I2C_SPEED
1488 to be the frequency (in Hz) at which you wish your i2c bus
1489 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie
1490 the CPU's i2c node address).
1492 Now, the u-boot i2c code for the mpc8xx
1493 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node
1494 and so its address should therefore be cleared to 0 (See,
1495 eg, MPC823e User's Manual p.16-473). So, set
1496 CONFIG_SYS_I2C_SLAVE to 0.
1498 CONFIG_SYS_I2C_INIT_MPC5XXX
1500 When a board is reset during an i2c bus transfer
1501 chips might think that the current transfer is still
1502 in progress. Reset the slave devices by sending start
1503 commands until the slave device responds.
1505 That's all that's required for CONFIG_HARD_I2C.
1507 If you use the software i2c interface (CONFIG_SOFT_I2C)
1508 then the following macros need to be defined (examples are
1509 from include/configs/lwmon.h):
1513 (Optional). Any commands necessary to enable the I2C
1514 controller or configure ports.
1516 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
1520 (Only for MPC8260 CPU). The I/O port to use (the code
1521 assumes both bits are on the same port). Valid values
1522 are 0..3 for ports A..D.
1526 The code necessary to make the I2C data line active
1527 (driven). If the data line is open collector, this
1530 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
1534 The code necessary to make the I2C data line tri-stated
1535 (inactive). If the data line is open collector, this
1538 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1542 Code that returns TRUE if the I2C data line is high,
1545 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1549 If <bit> is TRUE, sets the I2C data line high. If it
1550 is FALSE, it clears it (low).
1552 eg: #define I2C_SDA(bit) \
1553 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
1554 else immr->im_cpm.cp_pbdat &= ~PB_SDA
1558 If <bit> is TRUE, sets the I2C clock line high. If it
1559 is FALSE, it clears it (low).
1561 eg: #define I2C_SCL(bit) \
1562 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
1563 else immr->im_cpm.cp_pbdat &= ~PB_SCL
1567 This delay is invoked four times per clock cycle so this
1568 controls the rate of data transfer. The data rate thus
1569 is 1 / (I2C_DELAY * 4). Often defined to be something
1572 #define I2C_DELAY udelay(2)
1574 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
1576 If your arch supports the generic GPIO framework (asm/gpio.h),
1577 then you may alternatively define the two GPIOs that are to be
1578 used as SCL / SDA. Any of the previous I2C_xxx macros will
1579 have GPIO-based defaults assigned to them as appropriate.
1581 You should define these to the GPIO value as given directly to
1582 the generic GPIO functions.
1584 CONFIG_SYS_I2C_INIT_BOARD
1586 When a board is reset during an i2c bus transfer
1587 chips might think that the current transfer is still
1588 in progress. On some boards it is possible to access
1589 the i2c SCLK line directly, either by using the
1590 processor pin as a GPIO or by having a second pin
1591 connected to the bus. If this option is defined a
1592 custom i2c_init_board() routine in boards/xxx/board.c
1593 is run early in the boot sequence.
1595 CONFIG_SYS_I2C_BOARD_LATE_INIT
1597 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is
1598 defined a custom i2c_board_late_init() routine in
1599 boards/xxx/board.c is run AFTER the operations in i2c_init()
1600 is completed. This callpoint can be used to unreset i2c bus
1601 using CPU i2c controller register accesses for CPUs whose i2c
1602 controller provide such a method. It is called at the end of
1603 i2c_init() to allow i2c_init operations to setup the i2c bus
1604 controller on the CPU (e.g. setting bus speed & slave address).
1606 CONFIG_I2CFAST (PPC405GP|PPC405EP only)
1608 This option enables configuration of bi_iic_fast[] flags
1609 in u-boot bd_info structure based on u-boot environment
1610 variable "i2cfast". (see also i2cfast)
1612 CONFIG_I2C_MULTI_BUS
1614 This option allows the use of multiple I2C buses, each of which
1615 must have a controller. At any point in time, only one bus is
1616 active. To switch to a different bus, use the 'i2c dev' command.
1617 Note that bus numbering is zero-based.
1619 CONFIG_SYS_I2C_NOPROBES
1621 This option specifies a list of I2C devices that will be skipped
1622 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
1623 is set, specify a list of bus-device pairs. Otherwise, specify
1624 a 1D array of device addresses
1627 #undef CONFIG_I2C_MULTI_BUS
1628 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
1630 will skip addresses 0x50 and 0x68 on a board with one I2C bus
1632 #define CONFIG_I2C_MULTI_BUS
1633 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
1635 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
1637 CONFIG_SYS_SPD_BUS_NUM
1639 If defined, then this indicates the I2C bus number for DDR SPD.
1640 If not defined, then U-Boot assumes that SPD is on I2C bus 0.
1642 CONFIG_SYS_RTC_BUS_NUM
1644 If defined, then this indicates the I2C bus number for the RTC.
1645 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
1647 CONFIG_SYS_DTT_BUS_NUM
1649 If defined, then this indicates the I2C bus number for the DTT.
1650 If not defined, then U-Boot assumes that DTT is on I2C bus 0.
1652 CONFIG_SYS_I2C_DTT_ADDR:
1654 If defined, specifies the I2C address of the DTT device.
1655 If not defined, then U-Boot uses predefined value for
1656 specified DTT device.
1660 Define this option if you want to use Freescale's I2C driver in
1661 drivers/i2c/fsl_i2c.c.
1665 Define this option if you have I2C devices reached over 1 .. n
1666 I2C Muxes like the pca9544a. This option addes a new I2C
1667 Command "i2c bus [muxtype:muxaddr:muxchannel]" which adds a
1668 new I2C Bus to the existing I2C Busses. If you select the
1669 new Bus with "i2c dev", u-bbot sends first the commandos for
1670 the muxes to activate this new "bus".
1672 CONFIG_I2C_MULTI_BUS must be also defined, to use this
1676 Adding a new I2C Bus reached over 2 pca9544a muxes
1677 The First mux with address 70 and channel 6
1678 The Second mux with address 71 and channel 4
1680 => i2c bus pca9544a:70:6:pca9544a:71:4
1682 Use the "i2c bus" command without parameter, to get a list
1683 of I2C Busses with muxes:
1686 Busses reached over muxes:
1688 reached over Mux(es):
1691 reached over Mux(es):
1696 If you now switch to the new I2C Bus 3 with "i2c dev 3"
1697 u-boot sends First the Commando to the mux@70 to enable
1698 channel 6, and then the Commando to the mux@71 to enable
1701 After that, you can use the "normal" i2c commands as
1702 usual, to communicate with your I2C devices behind
1705 This option is actually implemented for the bitbanging
1706 algorithm in common/soft_i2c.c and for the Hardware I2C
1707 Bus on the MPC8260. But it should be not so difficult
1708 to add this option to other architectures.
1710 CONFIG_SOFT_I2C_READ_REPEATED_START
1712 defining this will force the i2c_read() function in
1713 the soft_i2c driver to perform an I2C repeated start
1714 between writing the address pointer and reading the
1715 data. If this define is omitted the default behaviour
1716 of doing a stop-start sequence will be used. Most I2C
1717 devices can use either method, but some require one or
1720 - SPI Support: CONFIG_SPI
1722 Enables SPI driver (so far only tested with
1723 SPI EEPROM, also an instance works with Crystal A/D and
1724 D/As on the SACSng board)
1728 Enables the driver for SPI controller on SuperH. Currently
1729 only SH7757 is supported.
1733 Enables extended (16-bit) SPI EEPROM addressing.
1734 (symmetrical to CONFIG_I2C_X)
1738 Enables a software (bit-bang) SPI driver rather than
1739 using hardware support. This is a general purpose
1740 driver that only requires three general I/O port pins
1741 (two outputs, one input) to function. If this is
1742 defined, the board configuration must define several
1743 SPI configuration items (port pins to use, etc). For
1744 an example, see include/configs/sacsng.h.
1748 Enables a hardware SPI driver for general-purpose reads
1749 and writes. As with CONFIG_SOFT_SPI, the board configuration
1750 must define a list of chip-select function pointers.
1751 Currently supported on some MPC8xxx processors. For an
1752 example, see include/configs/mpc8349emds.h.
1756 Enables the driver for the SPI controllers on i.MX and MXC
1757 SoCs. Currently only i.MX31 is supported.
1759 - FPGA Support: CONFIG_FPGA
1761 Enables FPGA subsystem.
1763 CONFIG_FPGA_<vendor>
1765 Enables support for specific chip vendors.
1768 CONFIG_FPGA_<family>
1770 Enables support for FPGA family.
1771 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
1775 Specify the number of FPGA devices to support.
1777 CONFIG_SYS_FPGA_PROG_FEEDBACK
1779 Enable printing of hash marks during FPGA configuration.
1781 CONFIG_SYS_FPGA_CHECK_BUSY
1783 Enable checks on FPGA configuration interface busy
1784 status by the configuration function. This option
1785 will require a board or device specific function to
1790 If defined, a function that provides delays in the FPGA
1791 configuration driver.
1793 CONFIG_SYS_FPGA_CHECK_CTRLC
1794 Allow Control-C to interrupt FPGA configuration
1796 CONFIG_SYS_FPGA_CHECK_ERROR
1798 Check for configuration errors during FPGA bitfile
1799 loading. For example, abort during Virtex II
1800 configuration if the INIT_B line goes low (which
1801 indicated a CRC error).
1803 CONFIG_SYS_FPGA_WAIT_INIT
1805 Maximum time to wait for the INIT_B line to deassert
1806 after PROB_B has been deasserted during a Virtex II
1807 FPGA configuration sequence. The default time is 500
1810 CONFIG_SYS_FPGA_WAIT_BUSY
1812 Maximum time to wait for BUSY to deassert during
1813 Virtex II FPGA configuration. The default is 5 ms.
1815 CONFIG_SYS_FPGA_WAIT_CONFIG
1817 Time to wait after FPGA configuration. The default is
1820 - Configuration Management:
1823 If defined, this string will be added to the U-Boot
1824 version information (U_BOOT_VERSION)
1826 - Vendor Parameter Protection:
1828 U-Boot considers the values of the environment
1829 variables "serial#" (Board Serial Number) and
1830 "ethaddr" (Ethernet Address) to be parameters that
1831 are set once by the board vendor / manufacturer, and
1832 protects these variables from casual modification by
1833 the user. Once set, these variables are read-only,
1834 and write or delete attempts are rejected. You can
1835 change this behaviour:
1837 If CONFIG_ENV_OVERWRITE is #defined in your config
1838 file, the write protection for vendor parameters is
1839 completely disabled. Anybody can change or delete
1842 Alternatively, if you #define _both_ CONFIG_ETHADDR
1843 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
1844 Ethernet address is installed in the environment,
1845 which can be changed exactly ONCE by the user. [The
1846 serial# is unaffected by this, i. e. it remains
1852 Define this variable to enable the reservation of
1853 "protected RAM", i. e. RAM which is not overwritten
1854 by U-Boot. Define CONFIG_PRAM to hold the number of
1855 kB you want to reserve for pRAM. You can overwrite
1856 this default value by defining an environment
1857 variable "pram" to the number of kB you want to
1858 reserve. Note that the board info structure will
1859 still show the full amount of RAM. If pRAM is
1860 reserved, a new environment variable "mem" will
1861 automatically be defined to hold the amount of
1862 remaining RAM in a form that can be passed as boot
1863 argument to Linux, for instance like that:
1865 setenv bootargs ... mem=\${mem}
1868 This way you can tell Linux not to use this memory,
1869 either, which results in a memory region that will
1870 not be affected by reboots.
1872 *WARNING* If your board configuration uses automatic
1873 detection of the RAM size, you must make sure that
1874 this memory test is non-destructive. So far, the
1875 following board configurations are known to be
1878 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL,
1879 HERMES, IP860, RPXlite, LWMON, LANTEC,
1885 Define this variable to stop the system in case of a
1886 fatal error, so that you have to reset it manually.
1887 This is probably NOT a good idea for an embedded
1888 system where you want the system to reboot
1889 automatically as fast as possible, but it may be
1890 useful during development since you can try to debug
1891 the conditions that lead to the situation.
1893 CONFIG_NET_RETRY_COUNT
1895 This variable defines the number of retries for
1896 network operations like ARP, RARP, TFTP, or BOOTP
1897 before giving up the operation. If not defined, a
1898 default value of 5 is used.
1902 Timeout waiting for an ARP reply in milliseconds.
1904 - Command Interpreter:
1905 CONFIG_AUTO_COMPLETE
1907 Enable auto completion of commands using TAB.
1909 Note that this feature has NOT been implemented yet
1910 for the "hush" shell.
1913 CONFIG_SYS_HUSH_PARSER
1915 Define this variable to enable the "hush" shell (from
1916 Busybox) as command line interpreter, thus enabling
1917 powerful command line syntax like
1918 if...then...else...fi conditionals or `&&' and '||'
1919 constructs ("shell scripts").
1921 If undefined, you get the old, much simpler behaviour
1922 with a somewhat smaller memory footprint.
1925 CONFIG_SYS_PROMPT_HUSH_PS2
1927 This defines the secondary prompt string, which is
1928 printed when the command interpreter needs more input
1929 to complete a command. Usually "> ".
1933 In the current implementation, the local variables
1934 space and global environment variables space are
1935 separated. Local variables are those you define by
1936 simply typing `name=value'. To access a local
1937 variable later on, you have write `$name' or
1938 `${name}'; to execute the contents of a variable
1939 directly type `$name' at the command prompt.
1941 Global environment variables are those you use
1942 setenv/printenv to work with. To run a command stored
1943 in such a variable, you need to use the run command,
1944 and you must not use the '$' sign to access them.
1946 To store commands and special characters in a
1947 variable, please use double quotation marks
1948 surrounding the whole text of the variable, instead
1949 of the backslashes before semicolons and special
1952 - Commandline Editing and History:
1953 CONFIG_CMDLINE_EDITING
1955 Enable editing and History functions for interactive
1956 commandline input operations
1958 - Default Environment:
1959 CONFIG_EXTRA_ENV_SETTINGS
1961 Define this to contain any number of null terminated
1962 strings (variable = value pairs) that will be part of
1963 the default environment compiled into the boot image.
1965 For example, place something like this in your
1966 board's config file:
1968 #define CONFIG_EXTRA_ENV_SETTINGS \
1972 Warning: This method is based on knowledge about the
1973 internal format how the environment is stored by the
1974 U-Boot code. This is NOT an official, exported
1975 interface! Although it is unlikely that this format
1976 will change soon, there is no guarantee either.
1977 You better know what you are doing here.
1979 Note: overly (ab)use of the default environment is
1980 discouraged. Make sure to check other ways to preset
1981 the environment like the "source" command or the
1984 - DataFlash Support:
1985 CONFIG_HAS_DATAFLASH
1987 Defining this option enables DataFlash features and
1988 allows to read/write in Dataflash via the standard
1991 - SystemACE Support:
1994 Adding this option adds support for Xilinx SystemACE
1995 chips attached via some sort of local bus. The address
1996 of the chip must also be defined in the
1997 CONFIG_SYS_SYSTEMACE_BASE macro. For example:
1999 #define CONFIG_SYSTEMACE
2000 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000
2002 When SystemACE support is added, the "ace" device type
2003 becomes available to the fat commands, i.e. fatls.
2005 - TFTP Fixed UDP Port:
2008 If this is defined, the environment variable tftpsrcp
2009 is used to supply the TFTP UDP source port value.
2010 If tftpsrcp isn't defined, the normal pseudo-random port
2011 number generator is used.
2013 Also, the environment variable tftpdstp is used to supply
2014 the TFTP UDP destination port value. If tftpdstp isn't
2015 defined, the normal port 69 is used.
2017 The purpose for tftpsrcp is to allow a TFTP server to
2018 blindly start the TFTP transfer using the pre-configured
2019 target IP address and UDP port. This has the effect of
2020 "punching through" the (Windows XP) firewall, allowing
2021 the remainder of the TFTP transfer to proceed normally.
2022 A better solution is to properly configure the firewall,
2023 but sometimes that is not allowed.
2025 - Show boot progress:
2026 CONFIG_SHOW_BOOT_PROGRESS
2028 Defining this option allows to add some board-
2029 specific code (calling a user-provided function
2030 "show_boot_progress(int)") that enables you to show
2031 the system's boot progress on some display (for
2032 example, some LED's) on your board. At the moment,
2033 the following checkpoints are implemented:
2035 - Standalone program support:
2036 CONFIG_STANDALONE_LOAD_ADDR
2038 This option allows to define board specific values
2039 for the address where standalone program gets loaded,
2040 thus overwriting the architecutre dependent default
2043 - Frame Buffer Address:
2046 Define CONFIG_FB_ADDR if you want to use specific address for
2048 Then system will reserve the frame buffer address to defined address
2049 instead of lcd_setmem (this function grab the memory for frame buffer
2052 Please see board_init_f function.
2054 If you want this config option then,
2055 please define it at your board config file
2057 Legacy uImage format:
2060 1 common/cmd_bootm.c before attempting to boot an image
2061 -1 common/cmd_bootm.c Image header has bad magic number
2062 2 common/cmd_bootm.c Image header has correct magic number
2063 -2 common/cmd_bootm.c Image header has bad checksum
2064 3 common/cmd_bootm.c Image header has correct checksum
2065 -3 common/cmd_bootm.c Image data has bad checksum
2066 4 common/cmd_bootm.c Image data has correct checksum
2067 -4 common/cmd_bootm.c Image is for unsupported architecture
2068 5 common/cmd_bootm.c Architecture check OK
2069 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
2070 6 common/cmd_bootm.c Image Type check OK
2071 -6 common/cmd_bootm.c gunzip uncompression error
2072 -7 common/cmd_bootm.c Unimplemented compression type
2073 7 common/cmd_bootm.c Uncompression OK
2074 8 common/cmd_bootm.c No uncompress/copy overwrite error
2075 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
2077 9 common/image.c Start initial ramdisk verification
2078 -10 common/image.c Ramdisk header has bad magic number
2079 -11 common/image.c Ramdisk header has bad checksum
2080 10 common/image.c Ramdisk header is OK
2081 -12 common/image.c Ramdisk data has bad checksum
2082 11 common/image.c Ramdisk data has correct checksum
2083 12 common/image.c Ramdisk verification complete, start loading
2084 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
2085 13 common/image.c Start multifile image verification
2086 14 common/image.c No initial ramdisk, no multifile, continue.
2088 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
2090 -30 arch/powerpc/lib/board.c Fatal error, hang the system
2091 -31 post/post.c POST test failed, detected by post_output_backlog()
2092 -32 post/post.c POST test failed, detected by post_run_single()
2094 34 common/cmd_doc.c before loading a Image from a DOC device
2095 -35 common/cmd_doc.c Bad usage of "doc" command
2096 35 common/cmd_doc.c correct usage of "doc" command
2097 -36 common/cmd_doc.c No boot device
2098 36 common/cmd_doc.c correct boot device
2099 -37 common/cmd_doc.c Unknown Chip ID on boot device
2100 37 common/cmd_doc.c correct chip ID found, device available
2101 -38 common/cmd_doc.c Read Error on boot device
2102 38 common/cmd_doc.c reading Image header from DOC device OK
2103 -39 common/cmd_doc.c Image header has bad magic number
2104 39 common/cmd_doc.c Image header has correct magic number
2105 -40 common/cmd_doc.c Error reading Image from DOC device
2106 40 common/cmd_doc.c Image header has correct magic number
2107 41 common/cmd_ide.c before loading a Image from a IDE device
2108 -42 common/cmd_ide.c Bad usage of "ide" command
2109 42 common/cmd_ide.c correct usage of "ide" command
2110 -43 common/cmd_ide.c No boot device
2111 43 common/cmd_ide.c boot device found
2112 -44 common/cmd_ide.c Device not available
2113 44 common/cmd_ide.c Device available
2114 -45 common/cmd_ide.c wrong partition selected
2115 45 common/cmd_ide.c partition selected
2116 -46 common/cmd_ide.c Unknown partition table
2117 46 common/cmd_ide.c valid partition table found
2118 -47 common/cmd_ide.c Invalid partition type
2119 47 common/cmd_ide.c correct partition type
2120 -48 common/cmd_ide.c Error reading Image Header on boot device
2121 48 common/cmd_ide.c reading Image Header from IDE device OK
2122 -49 common/cmd_ide.c Image header has bad magic number
2123 49 common/cmd_ide.c Image header has correct magic number
2124 -50 common/cmd_ide.c Image header has bad checksum
2125 50 common/cmd_ide.c Image header has correct checksum
2126 -51 common/cmd_ide.c Error reading Image from IDE device
2127 51 common/cmd_ide.c reading Image from IDE device OK
2128 52 common/cmd_nand.c before loading a Image from a NAND device
2129 -53 common/cmd_nand.c Bad usage of "nand" command
2130 53 common/cmd_nand.c correct usage of "nand" command
2131 -54 common/cmd_nand.c No boot device
2132 54 common/cmd_nand.c boot device found
2133 -55 common/cmd_nand.c Unknown Chip ID on boot device
2134 55 common/cmd_nand.c correct chip ID found, device available
2135 -56 common/cmd_nand.c Error reading Image Header on boot device
2136 56 common/cmd_nand.c reading Image Header from NAND device OK
2137 -57 common/cmd_nand.c Image header has bad magic number
2138 57 common/cmd_nand.c Image header has correct magic number
2139 -58 common/cmd_nand.c Error reading Image from NAND device
2140 58 common/cmd_nand.c reading Image from NAND device OK
2142 -60 common/env_common.c Environment has a bad CRC, using default
2144 64 net/eth.c starting with Ethernet configuration.
2145 -64 net/eth.c no Ethernet found.
2146 65 net/eth.c Ethernet found.
2148 -80 common/cmd_net.c usage wrong
2149 80 common/cmd_net.c before calling NetLoop()
2150 -81 common/cmd_net.c some error in NetLoop() occurred
2151 81 common/cmd_net.c NetLoop() back without error
2152 -82 common/cmd_net.c size == 0 (File with size 0 loaded)
2153 82 common/cmd_net.c trying automatic boot
2154 83 common/cmd_net.c running "source" command
2155 -83 common/cmd_net.c some error in automatic boot or "source" command
2156 84 common/cmd_net.c end without errors
2161 100 common/cmd_bootm.c Kernel FIT Image has correct format
2162 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
2163 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
2164 -101 common/cmd_bootm.c Can't get configuration for kernel subimage
2165 102 common/cmd_bootm.c Kernel unit name specified
2166 -103 common/cmd_bootm.c Can't get kernel subimage node offset
2167 103 common/cmd_bootm.c Found configuration node
2168 104 common/cmd_bootm.c Got kernel subimage node offset
2169 -104 common/cmd_bootm.c Kernel subimage hash verification failed
2170 105 common/cmd_bootm.c Kernel subimage hash verification OK
2171 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
2172 106 common/cmd_bootm.c Architecture check OK
2173 -106 common/cmd_bootm.c Kernel subimage has wrong type
2174 107 common/cmd_bootm.c Kernel subimage type OK
2175 -107 common/cmd_bootm.c Can't get kernel subimage data/size
2176 108 common/cmd_bootm.c Got kernel subimage data/size
2177 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
2178 -109 common/cmd_bootm.c Can't get kernel subimage type
2179 -110 common/cmd_bootm.c Can't get kernel subimage comp
2180 -111 common/cmd_bootm.c Can't get kernel subimage os
2181 -112 common/cmd_bootm.c Can't get kernel subimage load address
2182 -113 common/cmd_bootm.c Image uncompress/copy overwrite error
2184 120 common/image.c Start initial ramdisk verification
2185 -120 common/image.c Ramdisk FIT image has incorrect format
2186 121 common/image.c Ramdisk FIT image has correct format
2187 122 common/image.c No ramdisk subimage unit name, using configuration
2188 -122 common/image.c Can't get configuration for ramdisk subimage
2189 123 common/image.c Ramdisk unit name specified
2190 -124 common/image.c Can't get ramdisk subimage node offset
2191 125 common/image.c Got ramdisk subimage node offset
2192 -125 common/image.c Ramdisk subimage hash verification failed
2193 126 common/image.c Ramdisk subimage hash verification OK
2194 -126 common/image.c Ramdisk subimage for unsupported architecture
2195 127 common/image.c Architecture check OK
2196 -127 common/image.c Can't get ramdisk subimage data/size
2197 128 common/image.c Got ramdisk subimage data/size
2198 129 common/image.c Can't get ramdisk load address
2199 -129 common/image.c Got ramdisk load address
2201 -130 common/cmd_doc.c Incorrect FIT image format
2202 131 common/cmd_doc.c FIT image format OK
2204 -140 common/cmd_ide.c Incorrect FIT image format
2205 141 common/cmd_ide.c FIT image format OK
2207 -150 common/cmd_nand.c Incorrect FIT image format
2208 151 common/cmd_nand.c FIT image format OK
2210 - Automatic software updates via TFTP server
2212 CONFIG_UPDATE_TFTP_CNT_MAX
2213 CONFIG_UPDATE_TFTP_MSEC_MAX
2215 These options enable and control the auto-update feature;
2216 for a more detailed description refer to doc/README.update.
2218 - MTD Support (mtdparts command, UBI support)
2221 Adds the MTD device infrastructure from the Linux kernel.
2222 Needed for mtdparts command support.
2224 CONFIG_MTD_PARTITIONS
2226 Adds the MTD partitioning infrastructure from the Linux
2227 kernel. Needed for UBI support.
2233 [so far only for SMDK2400 and TRAB boards]
2235 - Modem support enable:
2236 CONFIG_MODEM_SUPPORT
2238 - RTS/CTS Flow control enable:
2241 - Modem debug support:
2242 CONFIG_MODEM_SUPPORT_DEBUG
2244 Enables debugging stuff (char screen[1024], dbg())
2245 for modem support. Useful only with BDI2000.
2247 - Interrupt support (PPC):
2249 There are common interrupt_init() and timer_interrupt()
2250 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
2251 for CPU specific initialization. interrupt_init_cpu()
2252 should set decrementer_count to appropriate value. If
2253 CPU resets decrementer automatically after interrupt
2254 (ppc4xx) it should set decrementer_count to zero.
2255 timer_interrupt() calls timer_interrupt_cpu() for CPU
2256 specific handling. If board has watchdog / status_led
2257 / other_activity_monitor it works automatically from
2258 general timer_interrupt().
2262 In the target system modem support is enabled when a
2263 specific key (key combination) is pressed during
2264 power-on. Otherwise U-Boot will boot normally
2265 (autoboot). The key_pressed() function is called from
2266 board_init(). Currently key_pressed() is a dummy
2267 function, returning 1 and thus enabling modem
2270 If there are no modem init strings in the
2271 environment, U-Boot proceed to autoboot; the
2272 previous output (banner, info printfs) will be
2275 See also: doc/README.Modem
2278 Configuration Settings:
2279 -----------------------
2281 - CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
2282 undefine this when you're short of memory.
2284 - CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
2285 width of the commands listed in the 'help' command output.
2287 - CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
2288 prompt for user input.
2290 - CONFIG_SYS_CBSIZE: Buffer size for input from the Console
2292 - CONFIG_SYS_PBSIZE: Buffer size for Console output
2294 - CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
2296 - CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
2297 the application (usually a Linux kernel) when it is
2300 - CONFIG_SYS_BAUDRATE_TABLE:
2301 List of legal baudrate settings for this board.
2303 - CONFIG_SYS_CONSOLE_INFO_QUIET
2304 Suppress display of console information at boot.
2306 - CONFIG_SYS_CONSOLE_IS_IN_ENV
2307 If the board specific function
2308 extern int overwrite_console (void);
2309 returns 1, the stdin, stderr and stdout are switched to the
2310 serial port, else the settings in the environment are used.
2312 - CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE
2313 Enable the call to overwrite_console().
2315 - CONFIG_SYS_CONSOLE_ENV_OVERWRITE
2316 Enable overwrite of previous console environment settings.
2318 - CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
2319 Begin and End addresses of the area used by the
2322 - CONFIG_SYS_ALT_MEMTEST:
2323 Enable an alternate, more extensive memory test.
2325 - CONFIG_SYS_MEMTEST_SCRATCH:
2326 Scratch address used by the alternate memory test
2327 You only need to set this if address zero isn't writeable
2329 - CONFIG_SYS_MEM_TOP_HIDE (PPC only):
2330 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
2331 this specified memory area will get subtracted from the top
2332 (end) of RAM and won't get "touched" at all by U-Boot. By
2333 fixing up gd->ram_size the Linux kernel should gets passed
2334 the now "corrected" memory size and won't touch it either.
2335 This should work for arch/ppc and arch/powerpc. Only Linux
2336 board ports in arch/powerpc with bootwrapper support that
2337 recalculate the memory size from the SDRAM controller setup
2338 will have to get fixed in Linux additionally.
2340 This option can be used as a workaround for the 440EPx/GRx
2341 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
2344 WARNING: Please make sure that this value is a multiple of
2345 the Linux page size (normally 4k). If this is not the case,
2346 then the end address of the Linux memory will be located at a
2347 non page size aligned address and this could cause major
2350 - CONFIG_SYS_TFTP_LOADADDR:
2351 Default load address for network file downloads
2353 - CONFIG_SYS_LOADS_BAUD_CHANGE:
2354 Enable temporary baudrate change while serial download
2356 - CONFIG_SYS_SDRAM_BASE:
2357 Physical start address of SDRAM. _Must_ be 0 here.
2359 - CONFIG_SYS_MBIO_BASE:
2360 Physical start address of Motherboard I/O (if using a
2363 - CONFIG_SYS_FLASH_BASE:
2364 Physical start address of Flash memory.
2366 - CONFIG_SYS_MONITOR_BASE:
2367 Physical start address of boot monitor code (set by
2368 make config files to be same as the text base address
2369 (CONFIG_SYS_TEXT_BASE) used when linking) - same as
2370 CONFIG_SYS_FLASH_BASE when booting from flash.
2372 - CONFIG_SYS_MONITOR_LEN:
2373 Size of memory reserved for monitor code, used to
2374 determine _at_compile_time_ (!) if the environment is
2375 embedded within the U-Boot image, or in a separate
2378 - CONFIG_SYS_MALLOC_LEN:
2379 Size of DRAM reserved for malloc() use.
2381 - CONFIG_SYS_BOOTM_LEN:
2382 Normally compressed uImages are limited to an
2383 uncompressed size of 8 MBytes. If this is not enough,
2384 you can define CONFIG_SYS_BOOTM_LEN in your board config file
2385 to adjust this setting to your needs.
2387 - CONFIG_SYS_BOOTMAPSZ:
2388 Maximum size of memory mapped by the startup code of
2389 the Linux kernel; all data that must be processed by
2390 the Linux kernel (bd_info, boot arguments, FDT blob if
2391 used) must be put below this limit, unless "bootm_low"
2392 enviroment variable is defined and non-zero. In such case
2393 all data for the Linux kernel must be between "bootm_low"
2394 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
2395 variable "bootm_mapsize" will override the value of
2396 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
2397 then the value in "bootm_size" will be used instead.
2399 - CONFIG_SYS_BOOT_RAMDISK_HIGH:
2400 Enable initrd_high functionality. If defined then the
2401 initrd_high feature is enabled and the bootm ramdisk subcommand
2404 - CONFIG_SYS_BOOT_GET_CMDLINE:
2405 Enables allocating and saving kernel cmdline in space between
2406 "bootm_low" and "bootm_low" + BOOTMAPSZ.
2408 - CONFIG_SYS_BOOT_GET_KBD:
2409 Enables allocating and saving a kernel copy of the bd_info in
2410 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
2412 - CONFIG_SYS_MAX_FLASH_BANKS:
2413 Max number of Flash memory banks
2415 - CONFIG_SYS_MAX_FLASH_SECT:
2416 Max number of sectors on a Flash chip
2418 - CONFIG_SYS_FLASH_ERASE_TOUT:
2419 Timeout for Flash erase operations (in ms)
2421 - CONFIG_SYS_FLASH_WRITE_TOUT:
2422 Timeout for Flash write operations (in ms)
2424 - CONFIG_SYS_FLASH_LOCK_TOUT
2425 Timeout for Flash set sector lock bit operation (in ms)
2427 - CONFIG_SYS_FLASH_UNLOCK_TOUT
2428 Timeout for Flash clear lock bits operation (in ms)
2430 - CONFIG_SYS_FLASH_PROTECTION
2431 If defined, hardware flash sectors protection is used
2432 instead of U-Boot software protection.
2434 - CONFIG_SYS_DIRECT_FLASH_TFTP:
2436 Enable TFTP transfers directly to flash memory;
2437 without this option such a download has to be
2438 performed in two steps: (1) download to RAM, and (2)
2439 copy from RAM to flash.
2441 The two-step approach is usually more reliable, since
2442 you can check if the download worked before you erase
2443 the flash, but in some situations (when system RAM is
2444 too limited to allow for a temporary copy of the
2445 downloaded image) this option may be very useful.
2447 - CONFIG_SYS_FLASH_CFI:
2448 Define if the flash driver uses extra elements in the
2449 common flash structure for storing flash geometry.
2451 - CONFIG_FLASH_CFI_DRIVER
2452 This option also enables the building of the cfi_flash driver
2453 in the drivers directory
2455 - CONFIG_FLASH_CFI_MTD
2456 This option enables the building of the cfi_mtd driver
2457 in the drivers directory. The driver exports CFI flash
2460 - CONFIG_SYS_FLASH_USE_BUFFER_WRITE
2461 Use buffered writes to flash.
2463 - CONFIG_FLASH_SPANSION_S29WS_N
2464 s29ws-n MirrorBit flash has non-standard addresses for buffered
2467 - CONFIG_SYS_FLASH_QUIET_TEST
2468 If this option is defined, the common CFI flash doesn't
2469 print it's warning upon not recognized FLASH banks. This
2470 is useful, if some of the configured banks are only
2471 optionally available.
2473 - CONFIG_FLASH_SHOW_PROGRESS
2474 If defined (must be an integer), print out countdown
2475 digits and dots. Recommended value: 45 (9..1) for 80
2476 column displays, 15 (3..1) for 40 column displays.
2478 - CONFIG_SYS_RX_ETH_BUFFER:
2479 Defines the number of Ethernet receive buffers. On some
2480 Ethernet controllers it is recommended to set this value
2481 to 8 or even higher (EEPRO100 or 405 EMAC), since all
2482 buffers can be full shortly after enabling the interface
2483 on high Ethernet traffic.
2484 Defaults to 4 if not defined.
2486 - CONFIG_ENV_MAX_ENTRIES
2488 Maximum number of entries in the hash table that is used
2489 internally to store the environment settings. The default
2490 setting is supposed to be generous and should work in most
2491 cases. This setting can be used to tune behaviour; see
2492 lib/hashtable.c for details.
2494 The following definitions that deal with the placement and management
2495 of environment data (variable area); in general, we support the
2496 following configurations:
2498 - CONFIG_ENV_IS_IN_FLASH:
2500 Define this if the environment is in flash memory.
2502 a) The environment occupies one whole flash sector, which is
2503 "embedded" in the text segment with the U-Boot code. This
2504 happens usually with "bottom boot sector" or "top boot
2505 sector" type flash chips, which have several smaller
2506 sectors at the start or the end. For instance, such a
2507 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
2508 such a case you would place the environment in one of the
2509 4 kB sectors - with U-Boot code before and after it. With
2510 "top boot sector" type flash chips, you would put the
2511 environment in one of the last sectors, leaving a gap
2512 between U-Boot and the environment.
2514 - CONFIG_ENV_OFFSET:
2516 Offset of environment data (variable area) to the
2517 beginning of flash memory; for instance, with bottom boot
2518 type flash chips the second sector can be used: the offset
2519 for this sector is given here.
2521 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE.
2525 This is just another way to specify the start address of
2526 the flash sector containing the environment (instead of
2529 - CONFIG_ENV_SECT_SIZE:
2531 Size of the sector containing the environment.
2534 b) Sometimes flash chips have few, equal sized, BIG sectors.
2535 In such a case you don't want to spend a whole sector for
2540 If you use this in combination with CONFIG_ENV_IS_IN_FLASH
2541 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part
2542 of this flash sector for the environment. This saves
2543 memory for the RAM copy of the environment.
2545 It may also save flash memory if you decide to use this
2546 when your environment is "embedded" within U-Boot code,
2547 since then the remainder of the flash sector could be used
2548 for U-Boot code. It should be pointed out that this is
2549 STRONGLY DISCOURAGED from a robustness point of view:
2550 updating the environment in flash makes it always
2551 necessary to erase the WHOLE sector. If something goes
2552 wrong before the contents has been restored from a copy in
2553 RAM, your target system will be dead.
2555 - CONFIG_ENV_ADDR_REDUND
2556 CONFIG_ENV_SIZE_REDUND
2558 These settings describe a second storage area used to hold
2559 a redundant copy of the environment data, so that there is
2560 a valid backup copy in case there is a power failure during
2561 a "saveenv" operation.
2563 BE CAREFUL! Any changes to the flash layout, and some changes to the
2564 source code will make it necessary to adapt <board>/u-boot.lds*
2568 - CONFIG_ENV_IS_IN_NVRAM:
2570 Define this if you have some non-volatile memory device
2571 (NVRAM, battery buffered SRAM) which you want to use for the
2577 These two #defines are used to determine the memory area you
2578 want to use for environment. It is assumed that this memory
2579 can just be read and written to, without any special
2582 BE CAREFUL! The first access to the environment happens quite early
2583 in U-Boot initalization (when we try to get the setting of for the
2584 console baudrate). You *MUST* have mapped your NVRAM area then, or
2587 Please note that even with NVRAM we still use a copy of the
2588 environment in RAM: we could work on NVRAM directly, but we want to
2589 keep settings there always unmodified except somebody uses "saveenv"
2590 to save the current settings.
2593 - CONFIG_ENV_IS_IN_EEPROM:
2595 Use this if you have an EEPROM or similar serial access
2596 device and a driver for it.
2598 - CONFIG_ENV_OFFSET:
2601 These two #defines specify the offset and size of the
2602 environment area within the total memory of your EEPROM.
2604 - CONFIG_SYS_I2C_EEPROM_ADDR:
2605 If defined, specified the chip address of the EEPROM device.
2606 The default address is zero.
2608 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS:
2609 If defined, the number of bits used to address bytes in a
2610 single page in the EEPROM device. A 64 byte page, for example
2611 would require six bits.
2613 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS:
2614 If defined, the number of milliseconds to delay between
2615 page writes. The default is zero milliseconds.
2617 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN:
2618 The length in bytes of the EEPROM memory array address. Note
2619 that this is NOT the chip address length!
2621 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW:
2622 EEPROM chips that implement "address overflow" are ones
2623 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
2624 address and the extra bits end up in the "chip address" bit
2625 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
2628 Note that we consider the length of the address field to
2629 still be one byte because the extra address bits are hidden
2630 in the chip address.
2632 - CONFIG_SYS_EEPROM_SIZE:
2633 The size in bytes of the EEPROM device.
2635 - CONFIG_ENV_EEPROM_IS_ON_I2C
2636 define this, if you have I2C and SPI activated, and your
2637 EEPROM, which holds the environment, is on the I2C bus.
2639 - CONFIG_I2C_ENV_EEPROM_BUS
2640 if you have an Environment on an EEPROM reached over
2641 I2C muxes, you can define here, how to reach this
2642 EEPROM. For example:
2644 #define CONFIG_I2C_ENV_EEPROM_BUS "pca9547:70:d\0"
2646 EEPROM which holds the environment, is reached over
2647 a pca9547 i2c mux with address 0x70, channel 3.
2649 - CONFIG_ENV_IS_IN_DATAFLASH:
2651 Define this if you have a DataFlash memory device which you
2652 want to use for the environment.
2654 - CONFIG_ENV_OFFSET:
2658 These three #defines specify the offset and size of the
2659 environment area within the total memory of your DataFlash placed
2660 at the specified address.
2662 - CONFIG_ENV_IS_IN_NAND:
2664 Define this if you have a NAND device which you want to use
2665 for the environment.
2667 - CONFIG_ENV_OFFSET:
2670 These two #defines specify the offset and size of the environment
2671 area within the first NAND device. CONFIG_ENV_OFFSET must be
2672 aligned to an erase block boundary.
2674 - CONFIG_ENV_OFFSET_REDUND (optional):
2676 This setting describes a second storage area of CONFIG_ENV_SIZE
2677 size used to hold a redundant copy of the environment data, so
2678 that there is a valid backup copy in case there is a power failure
2679 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be
2680 aligned to an erase block boundary.
2682 - CONFIG_ENV_RANGE (optional):
2684 Specifies the length of the region in which the environment
2685 can be written. This should be a multiple of the NAND device's
2686 block size. Specifying a range with more erase blocks than
2687 are needed to hold CONFIG_ENV_SIZE allows bad blocks within
2688 the range to be avoided.
2690 - CONFIG_ENV_OFFSET_OOB (optional):
2692 Enables support for dynamically retrieving the offset of the
2693 environment from block zero's out-of-band data. The
2694 "nand env.oob" command can be used to record this offset.
2695 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when
2696 using CONFIG_ENV_OFFSET_OOB.
2698 - CONFIG_NAND_ENV_DST
2700 Defines address in RAM to which the nand_spl code should copy the
2701 environment. If redundant environment is used, it will be copied to
2702 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
2704 - CONFIG_SYS_SPI_INIT_OFFSET
2706 Defines offset to the initial SPI buffer area in DPRAM. The
2707 area is used at an early stage (ROM part) if the environment
2708 is configured to reside in the SPI EEPROM: We need a 520 byte
2709 scratch DPRAM area. It is used between the two initialization
2710 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
2711 to be a good choice since it makes it far enough from the
2712 start of the data area as well as from the stack pointer.
2714 Please note that the environment is read-only until the monitor
2715 has been relocated to RAM and a RAM copy of the environment has been
2716 created; also, when using EEPROM you will have to use getenv_f()
2717 until then to read environment variables.
2719 The environment is protected by a CRC32 checksum. Before the monitor
2720 is relocated into RAM, as a result of a bad CRC you will be working
2721 with the compiled-in default environment - *silently*!!! [This is
2722 necessary, because the first environment variable we need is the
2723 "baudrate" setting for the console - if we have a bad CRC, we don't
2724 have any device yet where we could complain.]
2726 Note: once the monitor has been relocated, then it will complain if
2727 the default environment is used; a new CRC is computed as soon as you
2728 use the "saveenv" command to store a valid environment.
2730 - CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
2731 Echo the inverted Ethernet link state to the fault LED.
2733 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
2734 also needs to be defined.
2736 - CONFIG_SYS_FAULT_MII_ADDR:
2737 MII address of the PHY to check for the Ethernet link state.
2739 - CONFIG_NS16550_MIN_FUNCTIONS:
2740 Define this if you desire to only have use of the NS16550_init
2741 and NS16550_putc functions for the serial driver located at
2742 drivers/serial/ns16550.c. This option is useful for saving
2743 space for already greatly restricted images, including but not
2744 limited to NAND_SPL configurations.
2746 Low Level (hardware related) configuration options:
2747 ---------------------------------------------------
2749 - CONFIG_SYS_CACHELINE_SIZE:
2750 Cache Line Size of the CPU.
2752 - CONFIG_SYS_DEFAULT_IMMR:
2753 Default address of the IMMR after system reset.
2755 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
2756 and RPXsuper) to be able to adjust the position of
2757 the IMMR register after a reset.
2759 - Floppy Disk Support:
2760 CONFIG_SYS_FDC_DRIVE_NUMBER
2762 the default drive number (default value 0)
2764 CONFIG_SYS_ISA_IO_STRIDE
2766 defines the spacing between FDC chipset registers
2769 CONFIG_SYS_ISA_IO_OFFSET
2771 defines the offset of register from address. It
2772 depends on which part of the data bus is connected to
2773 the FDC chipset. (default value 0)
2775 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
2776 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
2779 if CONFIG_SYS_FDC_HW_INIT is defined, then the function
2780 fdc_hw_init() is called at the beginning of the FDC
2781 setup. fdc_hw_init() must be provided by the board
2782 source code. It is used to make hardware dependant
2786 Most IDE controllers were designed to be connected with PCI
2787 interface. Only few of them were designed for AHB interface.
2788 When software is doing ATA command and data transfer to
2789 IDE devices through IDE-AHB controller, some additional
2790 registers accessing to these kind of IDE-AHB controller
2793 - CONFIG_SYS_IMMR: Physical address of the Internal Memory.
2794 DO NOT CHANGE unless you know exactly what you're
2795 doing! (11-4) [MPC8xx/82xx systems only]
2797 - CONFIG_SYS_INIT_RAM_ADDR:
2799 Start address of memory area that can be used for
2800 initial data and stack; please note that this must be
2801 writable memory that is working WITHOUT special
2802 initialization, i. e. you CANNOT use normal RAM which
2803 will become available only after programming the
2804 memory controller and running certain initialization
2807 U-Boot uses the following memory types:
2808 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
2809 - MPC824X: data cache
2810 - PPC4xx: data cache
2812 - CONFIG_SYS_GBL_DATA_OFFSET:
2814 Offset of the initial data structure in the memory
2815 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
2816 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
2817 data is located at the end of the available space
2818 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
2819 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just
2820 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
2821 CONFIG_SYS_GBL_DATA_OFFSET) downward.
2824 On the MPC824X (or other systems that use the data
2825 cache for initial memory) the address chosen for
2826 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
2827 point to an otherwise UNUSED address space between
2828 the top of RAM and the start of the PCI space.
2830 - CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6)
2832 - CONFIG_SYS_SYPCR: System Protection Control (11-9)
2834 - CONFIG_SYS_TBSCR: Time Base Status and Control (11-26)
2836 - CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31)
2838 - CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
2840 - CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
2842 - CONFIG_SYS_OR_TIMING_SDRAM:
2845 - CONFIG_SYS_MAMR_PTA:
2846 periodic timer for refresh
2848 - CONFIG_SYS_DER: Debug Event Register (37-47)
2850 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
2851 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
2852 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
2853 CONFIG_SYS_BR1_PRELIM:
2854 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
2856 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
2857 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
2858 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
2859 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
2861 - CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K,
2862 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL:
2863 Machine Mode Register and Memory Periodic Timer
2864 Prescaler definitions (SDRAM timing)
2866 - CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]:
2867 enable I2C microcode relocation patch (MPC8xx);
2868 define relocation offset in DPRAM [DSP2]
2870 - CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]:
2871 enable SMC microcode relocation patch (MPC8xx);
2872 define relocation offset in DPRAM [SMC1]
2874 - CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]:
2875 enable SPI microcode relocation patch (MPC8xx);
2876 define relocation offset in DPRAM [SCC4]
2878 - CONFIG_SYS_USE_OSCCLK:
2879 Use OSCM clock mode on MBX8xx board. Be careful,
2880 wrong setting might damage your board. Read
2881 doc/README.MBX before setting this variable!
2883 - CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
2884 Offset of the bootmode word in DPRAM used by post
2885 (Power On Self Tests). This definition overrides
2886 #define'd default value in commproc.h resp.
2889 - CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB,
2890 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL,
2891 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS,
2892 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB,
2893 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
2894 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL,
2895 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE,
2896 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only)
2897 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set.
2899 - CONFIG_PCI_DISABLE_PCIE:
2900 Disable PCI-Express on systems where it is supported but not
2904 Chip has SRIO or not
2907 Board has SRIO 1 port available
2910 Board has SRIO 2 port available
2912 - CONFIG_SYS_SRIOn_MEM_VIRT:
2913 Virtual Address of SRIO port 'n' memory region
2915 - CONFIG_SYS_SRIOn_MEM_PHYS:
2916 Physical Address of SRIO port 'n' memory region
2918 - CONFIG_SYS_SRIOn_MEM_SIZE:
2919 Size of SRIO port 'n' memory region
2922 Get DDR timing information from an I2C EEPROM. Common
2923 with pluggable memory modules such as SODIMMs
2926 I2C address of the SPD EEPROM
2928 - CONFIG_SYS_SPD_BUS_NUM
2929 If SPD EEPROM is on an I2C bus other than the first
2930 one, specify here. Note that the value must resolve
2931 to something your driver can deal with.
2933 - CONFIG_SYS_83XX_DDR_USES_CS0
2934 Only for 83xx systems. If specified, then DDR should
2935 be configured using CS0 and CS1 instead of CS2 and CS3.
2937 - CONFIG_ETHER_ON_FEC[12]
2938 Define to enable FEC[12] on a 8xx series processor.
2940 - CONFIG_FEC[12]_PHY
2941 Define to the hardcoded PHY address which corresponds
2942 to the given FEC; i. e.
2943 #define CONFIG_FEC1_PHY 4
2944 means that the PHY with address 4 is connected to FEC1
2946 When set to -1, means to probe for first available.
2948 - CONFIG_FEC[12]_PHY_NORXERR
2949 The PHY does not have a RXERR line (RMII only).
2950 (so program the FEC to ignore it).
2953 Enable RMII mode for all FECs.
2954 Note that this is a global option, we can't
2955 have one FEC in standard MII mode and another in RMII mode.
2957 - CONFIG_CRC32_VERIFY
2958 Add a verify option to the crc32 command.
2961 => crc32 -v <address> <count> <crc32>
2963 Where address/count indicate a memory area
2964 and crc32 is the correct crc32 which the
2968 Add the "loopw" memory command. This only takes effect if
2969 the memory commands are activated globally (CONFIG_CMD_MEM).
2972 Add the "mdc" and "mwc" memory commands. These are cyclic
2977 This command will print 4 bytes (10,11,12,13) each 500 ms.
2979 => mwc.l 100 12345678 10
2980 This command will write 12345678 to address 100 all 10 ms.
2982 This only takes effect if the memory commands are activated
2983 globally (CONFIG_CMD_MEM).
2985 - CONFIG_SKIP_LOWLEVEL_INIT
2986 [ARM only] If this variable is defined, then certain
2987 low level initializations (like setting up the memory
2988 controller) are omitted and/or U-Boot does not
2989 relocate itself into RAM.
2991 Normally this variable MUST NOT be defined. The only
2992 exception is when U-Boot is loaded (to RAM) by some
2993 other boot loader or by a debugger which performs
2994 these initializations itself.
2997 Modifies the behaviour of start.S when compiling a loader
2998 that is executed before the actual U-Boot. E.g. when
2999 compiling a NAND SPL.
3001 - CONFIG_USE_ARCH_MEMCPY
3002 CONFIG_USE_ARCH_MEMSET
3003 If these options are used a optimized version of memcpy/memset will
3004 be used if available. These functions may be faster under some
3005 conditions but may increase the binary size.
3007 Building the Software:
3008 ======================
3010 Building U-Boot has been tested in several native build environments
3011 and in many different cross environments. Of course we cannot support
3012 all possibly existing versions of cross development tools in all
3013 (potentially obsolete) versions. In case of tool chain problems we
3014 recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
3015 which is extensively used to build and test U-Boot.
3017 If you are not using a native environment, it is assumed that you
3018 have GNU cross compiling tools available in your path. In this case,
3019 you must set the environment variable CROSS_COMPILE in your shell.
3020 Note that no changes to the Makefile or any other source files are
3021 necessary. For example using the ELDK on a 4xx CPU, please enter:
3023 $ CROSS_COMPILE=ppc_4xx-
3024 $ export CROSS_COMPILE
3026 Note: If you wish to generate Windows versions of the utilities in
3027 the tools directory you can use the MinGW toolchain
3028 (http://www.mingw.org). Set your HOST tools to the MinGW
3029 toolchain and execute 'make tools'. For example:
3031 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
3033 Binaries such as tools/mkimage.exe will be created which can
3034 be executed on computers running Windows.
3036 U-Boot is intended to be simple to build. After installing the
3037 sources you must configure U-Boot for one specific board type. This
3042 where "NAME_config" is the name of one of the existing configu-
3043 rations; see the main Makefile for supported names.
3045 Note: for some board special configuration names may exist; check if
3046 additional information is available from the board vendor; for
3047 instance, the TQM823L systems are available without (standard)
3048 or with LCD support. You can select such additional "features"
3049 when choosing the configuration, i. e.
3052 - will configure for a plain TQM823L, i. e. no LCD support
3054 make TQM823L_LCD_config
3055 - will configure for a TQM823L with U-Boot console on LCD
3060 Finally, type "make all", and you should get some working U-Boot
3061 images ready for download to / installation on your system:
3063 - "u-boot.bin" is a raw binary image
3064 - "u-boot" is an image in ELF binary format
3065 - "u-boot.srec" is in Motorola S-Record format
3067 By default the build is performed locally and the objects are saved
3068 in the source directory. One of the two methods can be used to change
3069 this behavior and build U-Boot to some external directory:
3071 1. Add O= to the make command line invocations:
3073 make O=/tmp/build distclean
3074 make O=/tmp/build NAME_config
3075 make O=/tmp/build all
3077 2. Set environment variable BUILD_DIR to point to the desired location:
3079 export BUILD_DIR=/tmp/build
3084 Note that the command line "O=" setting overrides the BUILD_DIR environment
3088 Please be aware that the Makefiles assume you are using GNU make, so
3089 for instance on NetBSD you might need to use "gmake" instead of
3093 If the system board that you have is not listed, then you will need
3094 to port U-Boot to your hardware platform. To do this, follow these
3097 1. Add a new configuration option for your board to the toplevel
3098 "Makefile" and to the "MAKEALL" script, using the existing
3099 entries as examples. Note that here and at many other places
3100 boards and other names are listed in alphabetical sort order. Please
3102 2. Create a new directory to hold your board specific code. Add any
3103 files you need. In your board directory, you will need at least
3104 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
3105 3. Create a new configuration file "include/configs/<board>.h" for
3107 3. If you're porting U-Boot to a new CPU, then also create a new
3108 directory to hold your CPU specific code. Add any files you need.
3109 4. Run "make <board>_config" with your new name.
3110 5. Type "make", and you should get a working "u-boot.srec" file
3111 to be installed on your target system.
3112 6. Debug and solve any problems that might arise.
3113 [Of course, this last step is much harder than it sounds.]
3116 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
3117 ==============================================================
3119 If you have modified U-Boot sources (for instance added a new board
3120 or support for new devices, a new CPU, etc.) you are expected to
3121 provide feedback to the other developers. The feedback normally takes
3122 the form of a "patch", i. e. a context diff against a certain (latest
3123 official or latest in the git repository) version of U-Boot sources.
3125 But before you submit such a patch, please verify that your modifi-
3126 cation did not break existing code. At least make sure that *ALL* of
3127 the supported boards compile WITHOUT ANY compiler warnings. To do so,
3128 just run the "MAKEALL" script, which will configure and build U-Boot
3129 for ALL supported system. Be warned, this will take a while. You can
3130 select which (cross) compiler to use by passing a `CROSS_COMPILE'
3131 environment variable to the script, i. e. to use the ELDK cross tools
3134 CROSS_COMPILE=ppc_8xx- MAKEALL
3136 or to build on a native PowerPC system you can type
3138 CROSS_COMPILE=' ' MAKEALL
3140 When using the MAKEALL script, the default behaviour is to build
3141 U-Boot in the source directory. This location can be changed by
3142 setting the BUILD_DIR environment variable. Also, for each target
3143 built, the MAKEALL script saves two log files (<target>.ERR and
3144 <target>.MAKEALL) in the <source dir>/LOG directory. This default
3145 location can be changed by setting the MAKEALL_LOGDIR environment
3146 variable. For example:
3148 export BUILD_DIR=/tmp/build
3149 export MAKEALL_LOGDIR=/tmp/log
3150 CROSS_COMPILE=ppc_8xx- MAKEALL
3152 With the above settings build objects are saved in the /tmp/build,
3153 log files are saved in the /tmp/log and the source tree remains clean
3154 during the whole build process.
3157 See also "U-Boot Porting Guide" below.
3160 Monitor Commands - Overview:
3161 ============================
3163 go - start application at address 'addr'
3164 run - run commands in an environment variable
3165 bootm - boot application image from memory
3166 bootp - boot image via network using BootP/TFTP protocol
3167 tftpboot- boot image via network using TFTP protocol
3168 and env variables "ipaddr" and "serverip"
3169 (and eventually "gatewayip")
3170 rarpboot- boot image via network using RARP/TFTP protocol
3171 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
3172 loads - load S-Record file over serial line
3173 loadb - load binary file over serial line (kermit mode)
3175 mm - memory modify (auto-incrementing)
3176 nm - memory modify (constant address)
3177 mw - memory write (fill)
3179 cmp - memory compare
3180 crc32 - checksum calculation
3181 i2c - I2C sub-system
3182 sspi - SPI utility commands
3183 base - print or set address offset
3184 printenv- print environment variables
3185 setenv - set environment variables
3186 saveenv - save environment variables to persistent storage
3187 protect - enable or disable FLASH write protection
3188 erase - erase FLASH memory
3189 flinfo - print FLASH memory information
3190 bdinfo - print Board Info structure
3191 iminfo - print header information for application image
3192 coninfo - print console devices and informations
3193 ide - IDE sub-system
3194 loop - infinite loop on address range
3195 loopw - infinite write loop on address range
3196 mtest - simple RAM test
3197 icache - enable or disable instruction cache
3198 dcache - enable or disable data cache
3199 reset - Perform RESET of the CPU
3200 echo - echo args to console
3201 version - print monitor version
3202 help - print online help
3203 ? - alias for 'help'
3206 Monitor Commands - Detailed Description:
3207 ========================================
3211 For now: just type "help <command>".
3214 Environment Variables:
3215 ======================
3217 U-Boot supports user configuration using Environment Variables which
3218 can be made persistent by saving to Flash memory.
3220 Environment Variables are set using "setenv", printed using
3221 "printenv", and saved to Flash using "saveenv". Using "setenv"
3222 without a value can be used to delete a variable from the
3223 environment. As long as you don't save the environment you are
3224 working with an in-memory copy. In case the Flash area containing the
3225 environment is erased by accident, a default environment is provided.
3227 Some configuration options can be set using Environment Variables.
3229 List of environment variables (most likely not complete):
3231 baudrate - see CONFIG_BAUDRATE
3233 bootdelay - see CONFIG_BOOTDELAY
3235 bootcmd - see CONFIG_BOOTCOMMAND
3237 bootargs - Boot arguments when booting an RTOS image
3239 bootfile - Name of the image to load with TFTP
3241 bootm_low - Memory range available for image processing in the bootm
3242 command can be restricted. This variable is given as
3243 a hexadecimal number and defines lowest address allowed
3244 for use by the bootm command. See also "bootm_size"
3245 environment variable. Address defined by "bootm_low" is
3246 also the base of the initial memory mapping for the Linux
3247 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
3250 bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
3251 This variable is given as a hexadecimal number and it
3252 defines the size of the memory region starting at base
3253 address bootm_low that is accessible by the Linux kernel
3254 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used
3255 as the default value if it is defined, and bootm_size is
3258 bootm_size - Memory range available for image processing in the bootm
3259 command can be restricted. This variable is given as
3260 a hexadecimal number and defines the size of the region
3261 allowed for use by the bootm command. See also "bootm_low"
3262 environment variable.
3264 updatefile - Location of the software update file on a TFTP server, used
3265 by the automatic software update feature. Please refer to
3266 documentation in doc/README.update for more details.
3268 autoload - if set to "no" (any string beginning with 'n'),
3269 "bootp" will just load perform a lookup of the
3270 configuration from the BOOTP server, but not try to
3271 load any image using TFTP
3273 autostart - if set to "yes", an image loaded using the "bootp",
3274 "rarpboot", "tftpboot" or "diskboot" commands will
3275 be automatically started (by internally calling
3278 If set to "no", a standalone image passed to the
3279 "bootm" command will be copied to the load address
3280 (and eventually uncompressed), but NOT be started.
3281 This can be used to load and uncompress arbitrary
3284 i2cfast - (PPC405GP|PPC405EP only)
3285 if set to 'y' configures Linux I2C driver for fast
3286 mode (400kHZ). This environment variable is used in
3287 initialization code. So, for changes to be effective
3288 it must be saved and board must be reset.
3290 initrd_high - restrict positioning of initrd images:
3291 If this variable is not set, initrd images will be
3292 copied to the highest possible address in RAM; this
3293 is usually what you want since it allows for
3294 maximum initrd size. If for some reason you want to
3295 make sure that the initrd image is loaded below the
3296 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
3297 variable to a value of "no" or "off" or "0".
3298 Alternatively, you can set it to a maximum upper
3299 address to use (U-Boot will still check that it
3300 does not overwrite the U-Boot stack and data).
3302 For instance, when you have a system with 16 MB
3303 RAM, and want to reserve 4 MB from use by Linux,
3304 you can do this by adding "mem=12M" to the value of
3305 the "bootargs" variable. However, now you must make
3306 sure that the initrd image is placed in the first
3307 12 MB as well - this can be done with
3309 setenv initrd_high 00c00000
3311 If you set initrd_high to 0xFFFFFFFF, this is an
3312 indication to U-Boot that all addresses are legal
3313 for the Linux kernel, including addresses in flash
3314 memory. In this case U-Boot will NOT COPY the
3315 ramdisk at all. This may be useful to reduce the
3316 boot time on your system, but requires that this
3317 feature is supported by your Linux kernel.
3319 ipaddr - IP address; needed for tftpboot command
3321 loadaddr - Default load address for commands like "bootp",
3322 "rarpboot", "tftpboot", "loadb" or "diskboot"
3324 loads_echo - see CONFIG_LOADS_ECHO
3326 serverip - TFTP server IP address; needed for tftpboot command
3328 bootretry - see CONFIG_BOOT_RETRY_TIME
3330 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
3332 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
3334 ethprime - When CONFIG_NET_MULTI is enabled controls which
3335 interface is used first.
3337 ethact - When CONFIG_NET_MULTI is enabled controls which
3338 interface is currently active. For example you
3339 can do the following
3341 => setenv ethact FEC
3342 => ping 192.168.0.1 # traffic sent on FEC
3343 => setenv ethact SCC
3344 => ping 10.0.0.1 # traffic sent on SCC
3346 ethrotate - When set to "no" U-Boot does not go through all
3347 available network interfaces.
3348 It just stays at the currently selected interface.
3350 netretry - When set to "no" each network operation will
3351 either succeed or fail without retrying.
3352 When set to "once" the network operation will
3353 fail when all the available network interfaces
3354 are tried once without success.
3355 Useful on scripts which control the retry operation
3358 npe_ucode - set load address for the NPE microcode
3360 tftpsrcport - If this is set, the value is used for TFTP's
3363 tftpdstport - If this is set, the value is used for TFTP's UDP
3364 destination port instead of the Well Know Port 69.
3366 tftpblocksize - Block size to use for TFTP transfers; if not set,
3367 we use the TFTP server's default block size
3369 tftptimeout - Retransmission timeout for TFTP packets (in milli-
3370 seconds, minimum value is 1000 = 1 second). Defines
3371 when a packet is considered to be lost so it has to
3372 be retransmitted. The default is 5000 = 5 seconds.
3373 Lowering this value may make downloads succeed
3374 faster in networks with high packet loss rates or
3375 with unreliable TFTP servers.
3377 vlan - When set to a value < 4095 the traffic over
3378 Ethernet is encapsulated/received over 802.1q
3381 The following environment variables may be used and automatically
3382 updated by the network boot commands ("bootp" and "rarpboot"),
3383 depending the information provided by your boot server:
3385 bootfile - see above
3386 dnsip - IP address of your Domain Name Server
3387 dnsip2 - IP address of your secondary Domain Name Server
3388 gatewayip - IP address of the Gateway (Router) to use
3389 hostname - Target hostname
3391 netmask - Subnet Mask
3392 rootpath - Pathname of the root filesystem on the NFS server
3393 serverip - see above
3396 There are two special Environment Variables:
3398 serial# - contains hardware identification information such
3399 as type string and/or serial number
3400 ethaddr - Ethernet address
3402 These variables can be set only once (usually during manufacturing of
3403 the board). U-Boot refuses to delete or overwrite these variables
3404 once they have been set once.
3407 Further special Environment Variables:
3409 ver - Contains the U-Boot version string as printed
3410 with the "version" command. This variable is
3411 readonly (see CONFIG_VERSION_VARIABLE).
3414 Please note that changes to some configuration parameters may take
3415 only effect after the next boot (yes, that's just like Windoze :-).
3418 Command Line Parsing:
3419 =====================
3421 There are two different command line parsers available with U-Boot:
3422 the old "simple" one, and the much more powerful "hush" shell:
3424 Old, simple command line parser:
3425 --------------------------------
3427 - supports environment variables (through setenv / saveenv commands)
3428 - several commands on one line, separated by ';'
3429 - variable substitution using "... ${name} ..." syntax
3430 - special characters ('$', ';') can be escaped by prefixing with '\',
3432 setenv bootcmd bootm \${address}
3433 - You can also escape text by enclosing in single apostrophes, for example:
3434 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
3439 - similar to Bourne shell, with control structures like
3440 if...then...else...fi, for...do...done; while...do...done,
3441 until...do...done, ...
3442 - supports environment ("global") variables (through setenv / saveenv
3443 commands) and local shell variables (through standard shell syntax
3444 "name=value"); only environment variables can be used with "run"
3450 (1) If a command line (or an environment variable executed by a "run"
3451 command) contains several commands separated by semicolon, and
3452 one of these commands fails, then the remaining commands will be
3455 (2) If you execute several variables with one call to run (i. e.
3456 calling run with a list of variables as arguments), any failing
3457 command will cause "run" to terminate, i. e. the remaining
3458 variables are not executed.
3460 Note for Redundant Ethernet Interfaces:
3461 =======================================
3463 Some boards come with redundant Ethernet interfaces; U-Boot supports
3464 such configurations and is capable of automatic selection of a
3465 "working" interface when needed. MAC assignment works as follows:
3467 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
3468 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
3469 "eth1addr" (=>eth1), "eth2addr", ...
3471 If the network interface stores some valid MAC address (for instance
3472 in SROM), this is used as default address if there is NO correspon-
3473 ding setting in the environment; if the corresponding environment
3474 variable is set, this overrides the settings in the card; that means:
3476 o If the SROM has a valid MAC address, and there is no address in the
3477 environment, the SROM's address is used.
3479 o If there is no valid address in the SROM, and a definition in the
3480 environment exists, then the value from the environment variable is
3483 o If both the SROM and the environment contain a MAC address, and
3484 both addresses are the same, this MAC address is used.
3486 o If both the SROM and the environment contain a MAC address, and the
3487 addresses differ, the value from the environment is used and a
3490 o If neither SROM nor the environment contain a MAC address, an error
3493 If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
3494 will be programmed into hardware as part of the initialization process. This
3495 may be skipped by setting the appropriate 'ethmacskip' environment variable.
3496 The naming convention is as follows:
3497 "ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
3502 U-Boot is capable of booting (and performing other auxiliary operations on)
3503 images in two formats:
3505 New uImage format (FIT)
3506 -----------------------
3508 Flexible and powerful format based on Flattened Image Tree -- FIT (similar
3509 to Flattened Device Tree). It allows the use of images with multiple
3510 components (several kernels, ramdisks, etc.), with contents protected by
3511 SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
3517 Old image format is based on binary files which can be basically anything,
3518 preceded by a special header; see the definitions in include/image.h for
3519 details; basically, the header defines the following image properties:
3521 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
3522 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
3523 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
3524 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
3526 * Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86,
3527 IA64, MIPS, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
3528 Currently supported: ARM, AVR32, Intel x86, MIPS, Nios II, PowerPC).
3529 * Compression Type (uncompressed, gzip, bzip2)
3535 The header is marked by a special Magic Number, and both the header
3536 and the data portions of the image are secured against corruption by
3543 Although U-Boot should support any OS or standalone application
3544 easily, the main focus has always been on Linux during the design of
3547 U-Boot includes many features that so far have been part of some
3548 special "boot loader" code within the Linux kernel. Also, any
3549 "initrd" images to be used are no longer part of one big Linux image;
3550 instead, kernel and "initrd" are separate images. This implementation
3551 serves several purposes:
3553 - the same features can be used for other OS or standalone
3554 applications (for instance: using compressed images to reduce the
3555 Flash memory footprint)
3557 - it becomes much easier to port new Linux kernel versions because
3558 lots of low-level, hardware dependent stuff are done by U-Boot
3560 - the same Linux kernel image can now be used with different "initrd"
3561 images; of course this also means that different kernel images can
3562 be run with the same "initrd". This makes testing easier (you don't
3563 have to build a new "zImage.initrd" Linux image when you just
3564 change a file in your "initrd"). Also, a field-upgrade of the
3565 software is easier now.
3571 Porting Linux to U-Boot based systems:
3572 ---------------------------------------
3574 U-Boot cannot save you from doing all the necessary modifications to
3575 configure the Linux device drivers for use with your target hardware
3576 (no, we don't intend to provide a full virtual machine interface to
3579 But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
3581 Just make sure your machine specific header file (for instance
3582 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
3583 Information structure as we define in include/asm-<arch>/u-boot.h,
3584 and make sure that your definition of IMAP_ADDR uses the same value
3585 as your U-Boot configuration in CONFIG_SYS_IMMR.
3588 Configuring the Linux kernel:
3589 -----------------------------
3591 No specific requirements for U-Boot. Make sure you have some root
3592 device (initial ramdisk, NFS) for your target system.
3595 Building a Linux Image:
3596 -----------------------
3598 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
3599 not used. If you use recent kernel source, a new build target
3600 "uImage" will exist which automatically builds an image usable by
3601 U-Boot. Most older kernels also have support for a "pImage" target,
3602 which was introduced for our predecessor project PPCBoot and uses a
3603 100% compatible format.
3612 The "uImage" build target uses a special tool (in 'tools/mkimage') to
3613 encapsulate a compressed Linux kernel image with header information,
3614 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
3616 * build a standard "vmlinux" kernel image (in ELF binary format):
3618 * convert the kernel into a raw binary image:
3620 ${CROSS_COMPILE}-objcopy -O binary \
3621 -R .note -R .comment \
3622 -S vmlinux linux.bin
3624 * compress the binary image:
3628 * package compressed binary image for U-Boot:
3630 mkimage -A ppc -O linux -T kernel -C gzip \
3631 -a 0 -e 0 -n "Linux Kernel Image" \
3632 -d linux.bin.gz uImage
3635 The "mkimage" tool can also be used to create ramdisk images for use
3636 with U-Boot, either separated from the Linux kernel image, or
3637 combined into one file. "mkimage" encapsulates the images with a 64
3638 byte header containing information about target architecture,
3639 operating system, image type, compression method, entry points, time
3640 stamp, CRC32 checksums, etc.
3642 "mkimage" can be called in two ways: to verify existing images and
3643 print the header information, or to build new images.
3645 In the first form (with "-l" option) mkimage lists the information
3646 contained in the header of an existing U-Boot image; this includes
3647 checksum verification:
3649 tools/mkimage -l image
3650 -l ==> list image header information
3652 The second form (with "-d" option) is used to build a U-Boot image
3653 from a "data file" which is used as image payload:
3655 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
3656 -n name -d data_file image
3657 -A ==> set architecture to 'arch'
3658 -O ==> set operating system to 'os'
3659 -T ==> set image type to 'type'
3660 -C ==> set compression type 'comp'
3661 -a ==> set load address to 'addr' (hex)
3662 -e ==> set entry point to 'ep' (hex)
3663 -n ==> set image name to 'name'
3664 -d ==> use image data from 'datafile'
3666 Right now, all Linux kernels for PowerPC systems use the same load
3667 address (0x00000000), but the entry point address depends on the
3670 - 2.2.x kernels have the entry point at 0x0000000C,
3671 - 2.3.x and later kernels have the entry point at 0x00000000.
3673 So a typical call to build a U-Boot image would read:
3675 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
3676 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
3677 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
3678 > examples/uImage.TQM850L
3679 Image Name: 2.4.4 kernel for TQM850L
3680 Created: Wed Jul 19 02:34:59 2000
3681 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3682 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
3683 Load Address: 0x00000000
3684 Entry Point: 0x00000000
3686 To verify the contents of the image (or check for corruption):
3688 -> tools/mkimage -l examples/uImage.TQM850L
3689 Image Name: 2.4.4 kernel for TQM850L
3690 Created: Wed Jul 19 02:34:59 2000
3691 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3692 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
3693 Load Address: 0x00000000
3694 Entry Point: 0x00000000
3696 NOTE: for embedded systems where boot time is critical you can trade
3697 speed for memory and install an UNCOMPRESSED image instead: this
3698 needs more space in Flash, but boots much faster since it does not
3699 need to be uncompressed:
3701 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
3702 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
3703 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
3704 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
3705 > examples/uImage.TQM850L-uncompressed
3706 Image Name: 2.4.4 kernel for TQM850L
3707 Created: Wed Jul 19 02:34:59 2000
3708 Image Type: PowerPC Linux Kernel Image (uncompressed)
3709 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
3710 Load Address: 0x00000000
3711 Entry Point: 0x00000000
3714 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
3715 when your kernel is intended to use an initial ramdisk:
3717 -> tools/mkimage -n 'Simple Ramdisk Image' \
3718 > -A ppc -O linux -T ramdisk -C gzip \
3719 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
3720 Image Name: Simple Ramdisk Image
3721 Created: Wed Jan 12 14:01:50 2000
3722 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3723 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
3724 Load Address: 0x00000000
3725 Entry Point: 0x00000000
3728 Installing a Linux Image:
3729 -------------------------
3731 To downloading a U-Boot image over the serial (console) interface,
3732 you must convert the image to S-Record format:
3734 objcopy -I binary -O srec examples/image examples/image.srec
3736 The 'objcopy' does not understand the information in the U-Boot
3737 image header, so the resulting S-Record file will be relative to
3738 address 0x00000000. To load it to a given address, you need to
3739 specify the target address as 'offset' parameter with the 'loads'
3742 Example: install the image to address 0x40100000 (which on the
3743 TQM8xxL is in the first Flash bank):
3745 => erase 40100000 401FFFFF
3751 ## Ready for S-Record download ...
3752 ~>examples/image.srec
3753 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
3755 15989 15990 15991 15992
3756 [file transfer complete]
3758 ## Start Addr = 0x00000000
3761 You can check the success of the download using the 'iminfo' command;
3762 this includes a checksum verification so you can be sure no data
3763 corruption happened:
3767 ## Checking Image at 40100000 ...
3768 Image Name: 2.2.13 for initrd on TQM850L
3769 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3770 Data Size: 335725 Bytes = 327 kB = 0 MB
3771 Load Address: 00000000
3772 Entry Point: 0000000c
3773 Verifying Checksum ... OK
3779 The "bootm" command is used to boot an application that is stored in
3780 memory (RAM or Flash). In case of a Linux kernel image, the contents
3781 of the "bootargs" environment variable is passed to the kernel as
3782 parameters. You can check and modify this variable using the
3783 "printenv" and "setenv" commands:
3786 => printenv bootargs
3787 bootargs=root=/dev/ram
3789 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3791 => printenv bootargs
3792 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3795 ## Booting Linux kernel at 40020000 ...
3796 Image Name: 2.2.13 for NFS on TQM850L
3797 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3798 Data Size: 381681 Bytes = 372 kB = 0 MB
3799 Load Address: 00000000
3800 Entry Point: 0000000c
3801 Verifying Checksum ... OK
3802 Uncompressing Kernel Image ... OK
3803 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
3804 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3805 time_init: decrementer frequency = 187500000/60
3806 Calibrating delay loop... 49.77 BogoMIPS
3807 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
3810 If you want to boot a Linux kernel with initial RAM disk, you pass
3811 the memory addresses of both the kernel and the initrd image (PPBCOOT
3812 format!) to the "bootm" command:
3814 => imi 40100000 40200000
3816 ## Checking Image at 40100000 ...
3817 Image Name: 2.2.13 for initrd on TQM850L
3818 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3819 Data Size: 335725 Bytes = 327 kB = 0 MB
3820 Load Address: 00000000
3821 Entry Point: 0000000c
3822 Verifying Checksum ... OK
3824 ## Checking Image at 40200000 ...
3825 Image Name: Simple Ramdisk Image
3826 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3827 Data Size: 566530 Bytes = 553 kB = 0 MB
3828 Load Address: 00000000
3829 Entry Point: 00000000
3830 Verifying Checksum ... OK
3832 => bootm 40100000 40200000
3833 ## Booting Linux kernel at 40100000 ...
3834 Image Name: 2.2.13 for initrd on TQM850L
3835 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3836 Data Size: 335725 Bytes = 327 kB = 0 MB
3837 Load Address: 00000000
3838 Entry Point: 0000000c
3839 Verifying Checksum ... OK
3840 Uncompressing Kernel Image ... OK
3841 ## Loading RAMDisk Image at 40200000 ...
3842 Image Name: Simple Ramdisk Image
3843 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3844 Data Size: 566530 Bytes = 553 kB = 0 MB
3845 Load Address: 00000000
3846 Entry Point: 00000000
3847 Verifying Checksum ... OK
3848 Loading Ramdisk ... OK
3849 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
3850 Boot arguments: root=/dev/ram
3851 time_init: decrementer frequency = 187500000/60
3852 Calibrating delay loop... 49.77 BogoMIPS
3854 RAMDISK: Compressed image found at block 0
3855 VFS: Mounted root (ext2 filesystem).
3859 Boot Linux and pass a flat device tree:
3862 First, U-Boot must be compiled with the appropriate defines. See the section
3863 titled "Linux Kernel Interface" above for a more in depth explanation. The
3864 following is an example of how to start a kernel and pass an updated
3870 oft=oftrees/mpc8540ads.dtb
3871 => tftp $oftaddr $oft
3872 Speed: 1000, full duplex
3874 TFTP from server 192.168.1.1; our IP address is 192.168.1.101
3875 Filename 'oftrees/mpc8540ads.dtb'.
3876 Load address: 0x300000
3879 Bytes transferred = 4106 (100a hex)
3880 => tftp $loadaddr $bootfile
3881 Speed: 1000, full duplex
3883 TFTP from server 192.168.1.1; our IP address is 192.168.1.2
3885 Load address: 0x200000
3886 Loading:############
3888 Bytes transferred = 1029407 (fb51f hex)
3893 => bootm $loadaddr - $oftaddr
3894 ## Booting image at 00200000 ...
3895 Image Name: Linux-2.6.17-dirty
3896 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3897 Data Size: 1029343 Bytes = 1005.2 kB
3898 Load Address: 00000000
3899 Entry Point: 00000000
3900 Verifying Checksum ... OK
3901 Uncompressing Kernel Image ... OK
3902 Booting using flat device tree at 0x300000
3903 Using MPC85xx ADS machine description
3904 Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
3908 More About U-Boot Image Types:
3909 ------------------------------
3911 U-Boot supports the following image types:
3913 "Standalone Programs" are directly runnable in the environment
3914 provided by U-Boot; it is expected that (if they behave
3915 well) you can continue to work in U-Boot after return from
3916 the Standalone Program.
3917 "OS Kernel Images" are usually images of some Embedded OS which
3918 will take over control completely. Usually these programs
3919 will install their own set of exception handlers, device
3920 drivers, set up the MMU, etc. - this means, that you cannot
3921 expect to re-enter U-Boot except by resetting the CPU.
3922 "RAMDisk Images" are more or less just data blocks, and their
3923 parameters (address, size) are passed to an OS kernel that is
3925 "Multi-File Images" contain several images, typically an OS
3926 (Linux) kernel image and one or more data images like
3927 RAMDisks. This construct is useful for instance when you want
3928 to boot over the network using BOOTP etc., where the boot
3929 server provides just a single image file, but you want to get
3930 for instance an OS kernel and a RAMDisk image.
3932 "Multi-File Images" start with a list of image sizes, each
3933 image size (in bytes) specified by an "uint32_t" in network
3934 byte order. This list is terminated by an "(uint32_t)0".
3935 Immediately after the terminating 0 follow the images, one by
3936 one, all aligned on "uint32_t" boundaries (size rounded up to
3937 a multiple of 4 bytes).
3939 "Firmware Images" are binary images containing firmware (like
3940 U-Boot or FPGA images) which usually will be programmed to
3943 "Script files" are command sequences that will be executed by
3944 U-Boot's command interpreter; this feature is especially
3945 useful when you configure U-Boot to use a real shell (hush)
3946 as command interpreter.
3952 One of the features of U-Boot is that you can dynamically load and
3953 run "standalone" applications, which can use some resources of
3954 U-Boot like console I/O functions or interrupt services.
3956 Two simple examples are included with the sources:
3961 'examples/hello_world.c' contains a small "Hello World" Demo
3962 application; it is automatically compiled when you build U-Boot.
3963 It's configured to run at address 0x00040004, so you can play with it
3967 ## Ready for S-Record download ...
3968 ~>examples/hello_world.srec
3969 1 2 3 4 5 6 7 8 9 10 11 ...
3970 [file transfer complete]
3972 ## Start Addr = 0x00040004
3974 => go 40004 Hello World! This is a test.
3975 ## Starting application at 0x00040004 ...
3986 Hit any key to exit ...
3988 ## Application terminated, rc = 0x0
3990 Another example, which demonstrates how to register a CPM interrupt
3991 handler with the U-Boot code, can be found in 'examples/timer.c'.
3992 Here, a CPM timer is set up to generate an interrupt every second.
3993 The interrupt service routine is trivial, just printing a '.'
3994 character, but this is just a demo program. The application can be
3995 controlled by the following keys:
3997 ? - print current values og the CPM Timer registers
3998 b - enable interrupts and start timer
3999 e - stop timer and disable interrupts
4000 q - quit application
4003 ## Ready for S-Record download ...
4004 ~>examples/timer.srec
4005 1 2 3 4 5 6 7 8 9 10 11 ...
4006 [file transfer complete]
4008 ## Start Addr = 0x00040004
4011 ## Starting application at 0x00040004 ...
4014 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
4017 [q, b, e, ?] Set interval 1000000 us
4020 [q, b, e, ?] ........
4021 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
4024 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
4027 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
4030 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
4032 [q, b, e, ?] ...Stopping timer
4034 [q, b, e, ?] ## Application terminated, rc = 0x0
4040 Over time, many people have reported problems when trying to use the
4041 "minicom" terminal emulation program for serial download. I (wd)
4042 consider minicom to be broken, and recommend not to use it. Under
4043 Unix, I recommend to use C-Kermit for general purpose use (and
4044 especially for kermit binary protocol download ("loadb" command), and
4045 use "cu" for S-Record download ("loads" command).
4047 Nevertheless, if you absolutely want to use it try adding this
4048 configuration to your "File transfer protocols" section:
4050 Name Program Name U/D FullScr IO-Red. Multi
4051 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
4052 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
4058 Starting at version 0.9.2, U-Boot supports NetBSD both as host
4059 (build U-Boot) and target system (boots NetBSD/mpc8xx).
4061 Building requires a cross environment; it is known to work on
4062 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
4063 need gmake since the Makefiles are not compatible with BSD make).
4064 Note that the cross-powerpc package does not install include files;
4065 attempting to build U-Boot will fail because <machine/ansi.h> is
4066 missing. This file has to be installed and patched manually:
4068 # cd /usr/pkg/cross/powerpc-netbsd/include
4070 # ln -s powerpc machine
4071 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
4072 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
4074 Native builds *don't* work due to incompatibilities between native
4075 and U-Boot include files.
4077 Booting assumes that (the first part of) the image booted is a
4078 stage-2 loader which in turn loads and then invokes the kernel
4079 proper. Loader sources will eventually appear in the NetBSD source
4080 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
4081 meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
4084 Implementation Internals:
4085 =========================
4087 The following is not intended to be a complete description of every
4088 implementation detail. However, it should help to understand the
4089 inner workings of U-Boot and make it easier to port it to custom
4093 Initial Stack, Global Data:
4094 ---------------------------
4096 The implementation of U-Boot is complicated by the fact that U-Boot
4097 starts running out of ROM (flash memory), usually without access to
4098 system RAM (because the memory controller is not initialized yet).
4099 This means that we don't have writable Data or BSS segments, and BSS
4100 is not initialized as zero. To be able to get a C environment working
4101 at all, we have to allocate at least a minimal stack. Implementation
4102 options for this are defined and restricted by the CPU used: Some CPU
4103 models provide on-chip memory (like the IMMR area on MPC8xx and
4104 MPC826x processors), on others (parts of) the data cache can be
4105 locked as (mis-) used as memory, etc.
4107 Chris Hallinan posted a good summary of these issues to the
4108 U-Boot mailing list:
4110 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
4111 From: "Chris Hallinan" <clh@net1plus.com>
4112 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
4115 Correct me if I'm wrong, folks, but the way I understand it
4116 is this: Using DCACHE as initial RAM for Stack, etc, does not
4117 require any physical RAM backing up the cache. The cleverness
4118 is that the cache is being used as a temporary supply of
4119 necessary storage before the SDRAM controller is setup. It's
4120 beyond the scope of this list to explain the details, but you
4121 can see how this works by studying the cache architecture and
4122 operation in the architecture and processor-specific manuals.
4124 OCM is On Chip Memory, which I believe the 405GP has 4K. It
4125 is another option for the system designer to use as an
4126 initial stack/RAM area prior to SDRAM being available. Either
4127 option should work for you. Using CS 4 should be fine if your
4128 board designers haven't used it for something that would
4129 cause you grief during the initial boot! It is frequently not
4132 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
4133 with your processor/board/system design. The default value
4134 you will find in any recent u-boot distribution in
4135 walnut.h should work for you. I'd set it to a value larger
4136 than your SDRAM module. If you have a 64MB SDRAM module, set
4137 it above 400_0000. Just make sure your board has no resources
4138 that are supposed to respond to that address! That code in
4139 start.S has been around a while and should work as is when
4140 you get the config right.
4145 It is essential to remember this, since it has some impact on the C
4146 code for the initialization procedures:
4148 * Initialized global data (data segment) is read-only. Do not attempt
4151 * Do not use any uninitialized global data (or implicitely initialized
4152 as zero data - BSS segment) at all - this is undefined, initiali-
4153 zation is performed later (when relocating to RAM).
4155 * Stack space is very limited. Avoid big data buffers or things like
4158 Having only the stack as writable memory limits means we cannot use
4159 normal global data to share information beween the code. But it
4160 turned out that the implementation of U-Boot can be greatly
4161 simplified by making a global data structure (gd_t) available to all
4162 functions. We could pass a pointer to this data as argument to _all_
4163 functions, but this would bloat the code. Instead we use a feature of
4164 the GCC compiler (Global Register Variables) to share the data: we
4165 place a pointer (gd) to the global data into a register which we
4166 reserve for this purpose.
4168 When choosing a register for such a purpose we are restricted by the
4169 relevant (E)ABI specifications for the current architecture, and by
4170 GCC's implementation.
4172 For PowerPC, the following registers have specific use:
4174 R2: reserved for system use
4175 R3-R4: parameter passing and return values
4176 R5-R10: parameter passing
4177 R13: small data area pointer
4181 (U-Boot also uses R12 as internal GOT pointer. r12
4182 is a volatile register so r12 needs to be reset when
4183 going back and forth between asm and C)
4185 ==> U-Boot will use R2 to hold a pointer to the global data
4187 Note: on PPC, we could use a static initializer (since the
4188 address of the global data structure is known at compile time),
4189 but it turned out that reserving a register results in somewhat
4190 smaller code - although the code savings are not that big (on
4191 average for all boards 752 bytes for the whole U-Boot image,
4192 624 text + 127 data).
4194 On Blackfin, the normal C ABI (except for P3) is followed as documented here:
4195 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface
4197 ==> U-Boot will use P3 to hold a pointer to the global data
4199 On ARM, the following registers are used:
4201 R0: function argument word/integer result
4202 R1-R3: function argument word
4204 R10: stack limit (used only if stack checking if enabled)
4205 R11: argument (frame) pointer
4206 R12: temporary workspace
4209 R15: program counter
4211 ==> U-Boot will use R8 to hold a pointer to the global data
4213 On Nios II, the ABI is documented here:
4214 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
4216 ==> U-Boot will use gp to hold a pointer to the global data
4218 Note: on Nios II, we give "-G0" option to gcc and don't use gp
4219 to access small data sections, so gp is free.
4221 NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
4222 or current versions of GCC may "optimize" the code too much.
4227 U-Boot runs in system state and uses physical addresses, i.e. the
4228 MMU is not used either for address mapping nor for memory protection.
4230 The available memory is mapped to fixed addresses using the memory
4231 controller. In this process, a contiguous block is formed for each
4232 memory type (Flash, SDRAM, SRAM), even when it consists of several
4233 physical memory banks.
4235 U-Boot is installed in the first 128 kB of the first Flash bank (on
4236 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
4237 booting and sizing and initializing DRAM, the code relocates itself
4238 to the upper end of DRAM. Immediately below the U-Boot code some
4239 memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
4240 configuration setting]. Below that, a structure with global Board
4241 Info data is placed, followed by the stack (growing downward).
4243 Additionally, some exception handler code is copied to the low 8 kB
4244 of DRAM (0x00000000 ... 0x00001FFF).
4246 So a typical memory configuration with 16 MB of DRAM could look like
4249 0x0000 0000 Exception Vector code
4252 0x0000 2000 Free for Application Use
4258 0x00FB FF20 Monitor Stack (Growing downward)
4259 0x00FB FFAC Board Info Data and permanent copy of global data
4260 0x00FC 0000 Malloc Arena
4263 0x00FE 0000 RAM Copy of Monitor Code
4264 ... eventually: LCD or video framebuffer
4265 ... eventually: pRAM (Protected RAM - unchanged by reset)
4266 0x00FF FFFF [End of RAM]
4269 System Initialization:
4270 ----------------------
4272 In the reset configuration, U-Boot starts at the reset entry point
4273 (on most PowerPC systems at address 0x00000100). Because of the reset
4274 configuration for CS0# this is a mirror of the onboard Flash memory.
4275 To be able to re-map memory U-Boot then jumps to its link address.
4276 To be able to implement the initialization code in C, a (small!)
4277 initial stack is set up in the internal Dual Ported RAM (in case CPUs
4278 which provide such a feature like MPC8xx or MPC8260), or in a locked
4279 part of the data cache. After that, U-Boot initializes the CPU core,
4280 the caches and the SIU.
4282 Next, all (potentially) available memory banks are mapped using a
4283 preliminary mapping. For example, we put them on 512 MB boundaries
4284 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
4285 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
4286 programmed for SDRAM access. Using the temporary configuration, a
4287 simple memory test is run that determines the size of the SDRAM
4290 When there is more than one SDRAM bank, and the banks are of
4291 different size, the largest is mapped first. For equal size, the first
4292 bank (CS2#) is mapped first. The first mapping is always for address
4293 0x00000000, with any additional banks following immediately to create
4294 contiguous memory starting from 0.
4296 Then, the monitor installs itself at the upper end of the SDRAM area
4297 and allocates memory for use by malloc() and for the global Board
4298 Info data; also, the exception vector code is copied to the low RAM
4299 pages, and the final stack is set up.
4301 Only after this relocation will you have a "normal" C environment;
4302 until that you are restricted in several ways, mostly because you are
4303 running from ROM, and because the code will have to be relocated to a
4307 U-Boot Porting Guide:
4308 ----------------------
4310 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
4314 int main(int argc, char *argv[])
4316 sighandler_t no_more_time;
4318 signal(SIGALRM, no_more_time);
4319 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
4321 if (available_money > available_manpower) {
4322 Pay consultant to port U-Boot;
4326 Download latest U-Boot source;
4328 Subscribe to u-boot mailing list;
4331 email("Hi, I am new to U-Boot, how do I get started?");
4334 Read the README file in the top level directory;
4335 Read http://www.denx.de/twiki/bin/view/DULG/Manual;
4336 Read applicable doc/*.README;
4337 Read the source, Luke;
4338 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
4341 if (available_money > toLocalCurrency ($2500))
4344 Add a lot of aggravation and time;
4346 if (a similar board exists) { /* hopefully... */
4347 cp -a board/<similar> board/<myboard>
4348 cp include/configs/<similar>.h include/configs/<myboard>.h
4350 Create your own board support subdirectory;
4351 Create your own board include/configs/<myboard>.h file;
4353 Edit new board/<myboard> files
4354 Edit new include/configs/<myboard>.h
4359 Add / modify source code;
4363 email("Hi, I am having problems...");
4365 Send patch file to the U-Boot email list;
4366 if (reasonable critiques)
4367 Incorporate improvements from email list code review;
4369 Defend code as written;
4375 void no_more_time (int sig)
4384 All contributions to U-Boot should conform to the Linux kernel
4385 coding style; see the file "Documentation/CodingStyle" and the script
4386 "scripts/Lindent" in your Linux kernel source directory. In sources
4387 originating from U-Boot a style corresponding to "Lindent -pcs" (adding
4388 spaces before parameters to function calls) is actually used.
4390 Source files originating from a different project (for example the
4391 MTD subsystem) are generally exempt from these guidelines and are not
4392 reformated to ease subsequent migration to newer versions of those
4395 Please note that U-Boot is implemented in C (and to some small parts in
4396 Assembler); no C++ is used, so please do not use C++ style comments (//)
4399 Please also stick to the following formatting rules:
4400 - remove any trailing white space
4401 - use TAB characters for indentation, not spaces
4402 - make sure NOT to use DOS '\r\n' line feeds
4403 - do not add more than 2 empty lines to source files
4404 - do not add trailing empty lines to source files
4406 Submissions which do not conform to the standards may be returned
4407 with a request to reformat the changes.
4413 Since the number of patches for U-Boot is growing, we need to
4414 establish some rules. Submissions which do not conform to these rules
4415 may be rejected, even when they contain important and valuable stuff.
4417 Please see http://www.denx.de/wiki/U-Boot/Patches for details.
4419 Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
4420 see http://lists.denx.de/mailman/listinfo/u-boot
4422 When you send a patch, please include the following information with
4425 * For bug fixes: a description of the bug and how your patch fixes
4426 this bug. Please try to include a way of demonstrating that the
4427 patch actually fixes something.
4429 * For new features: a description of the feature and your
4432 * A CHANGELOG entry as plaintext (separate from the patch)
4434 * For major contributions, your entry to the CREDITS file
4436 * When you add support for a new board, don't forget to add this
4437 board to the MAKEALL script, too.
4439 * If your patch adds new configuration options, don't forget to
4440 document these in the README file.
4442 * The patch itself. If you are using git (which is *strongly*
4443 recommended) you can easily generate the patch using the
4444 "git-format-patch". If you then use "git-send-email" to send it to
4445 the U-Boot mailing list, you will avoid most of the common problems
4446 with some other mail clients.
4448 If you cannot use git, use "diff -purN OLD NEW". If your version of
4449 diff does not support these options, then get the latest version of
4452 The current directory when running this command shall be the parent
4453 directory of the U-Boot source tree (i. e. please make sure that
4454 your patch includes sufficient directory information for the
4457 We prefer patches as plain text. MIME attachments are discouraged,
4458 and compressed attachments must not be used.
4460 * If one logical set of modifications affects or creates several
4461 files, all these changes shall be submitted in a SINGLE patch file.
4463 * Changesets that contain different, unrelated modifications shall be
4464 submitted as SEPARATE patches, one patch per changeset.
4469 * Before sending the patch, run the MAKEALL script on your patched
4470 source tree and make sure that no errors or warnings are reported
4471 for any of the boards.
4473 * Keep your modifications to the necessary minimum: A patch
4474 containing several unrelated changes or arbitrary reformats will be
4475 returned with a request to re-formatting / split it.
4477 * If you modify existing code, make sure that your new code does not
4478 add to the memory footprint of the code ;-) Small is beautiful!
4479 When adding new features, these should compile conditionally only
4480 (using #ifdef), and the resulting code with the new feature
4481 disabled must not need more memory than the old code without your
4484 * Remember that there is a size limit of 100 kB per message on the
4485 u-boot mailing list. Bigger patches will be moderated. If they are
4486 reasonable and not too big, they will be acknowledged. But patches
4487 bigger than the size limit should be avoided.
projects / karo-tx-uboot.git / blob