2 # (C) Copyright 2000 - 2004
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 and ARM processors, which can be
29 installed in a boot ROM and used to initialize and test the hardware
30 or to download and run application code.
32 The development of U-Boot is closely related to Linux: some parts of
33 the source code originate in the Linux source tree, we have some
34 header files in common, and special provision has been made to
35 support booting of Linux images.
37 Some attention has been paid to make this software easily
38 configurable and extendable. For instance, all monitor commands are
39 implemented with the same call interface, so that it's very easy to
40 add new commands. Also, instead of permanently adding rarely used
41 code (for instance hardware test utilities) to the monitor, you can
42 load and run it dynamically.
48 In general, all boards for which a configuration option exists in the
49 Makefile have been tested to some extent and can be considered
50 "working". In fact, many of them are used in production systems.
52 In case of problems see the CHANGELOG and CREDITS files to find out
53 who contributed the specific port.
59 In case you have questions about, problems with or contributions for
60 U-Boot you should send a message to the U-Boot mailing list at
61 <u-boot-users@lists.sourceforge.net>. There is also an archive of
62 previous traffic on the mailing list - please search the archive
63 before asking FAQ's. Please see
64 http://lists.sourceforge.net/lists/listinfo/u-boot-users/
70 - start from 8xxrom sources
71 - create PPCBoot project (http://sourceforge.net/projects/ppcboot)
73 - make it easier to add custom boards
74 - make it possible to add other [PowerPC] CPUs
75 - extend functions, especially:
76 * Provide extended interface to Linux boot loader
79 * PCMCIA / CompactFLash / ATA disk / SCSI ... boot
80 - create ARMBoot project (http://sourceforge.net/projects/armboot)
81 - add other CPU families (starting with ARM)
82 - create U-Boot project (http://sourceforge.net/projects/u-boot)
88 The "official" name of this project is "Das U-Boot". The spelling
89 "U-Boot" shall be used in all written text (documentation, comments
90 in source files etc.). Example:
92 This is the README file for the U-Boot project.
94 File names etc. shall be based on the string "u-boot". Examples:
96 include/asm-ppc/u-boot.h
98 #include <asm/u-boot.h>
100 Variable names, preprocessor constants etc. shall be either based on
101 the string "u_boot" or on "U_BOOT". Example:
103 U_BOOT_VERSION u_boot_logo
104 IH_OS_U_BOOT u_boot_hush_start
110 U-Boot uses a 3 level version number containing a version, a
111 sub-version, and a patchlevel: "U-Boot-2.34.5" means version "2",
112 sub-version "34", and patchlevel "4".
114 The patchlevel is used to indicate certain stages of development
115 between released versions, i. e. officially released versions of
116 U-Boot will always have a patchlevel of "0".
122 - board Board dependent files
123 - common Misc architecture independent functions
124 - cpu CPU specific files
125 - disk Code for disk drive partition handling
126 - doc Documentation (don't expect too much)
127 - drivers Commonly used device drivers
128 - dtt Digital Thermometer and Thermostat drivers
129 - examples Example code for standalone applications, etc.
130 - include Header Files
131 - disk Harddisk interface code
132 - net Networking code
133 - ppc Files generic to PowerPC architecture
134 - post Power On Self Test
135 - post/arch Symlink to architecture specific Power On Self Test
136 - post/arch-ppc PowerPC architecture specific Power On Self Test
137 - post/cpu/mpc8260 MPC8260 CPU specific Power On Self Test
138 - post/cpu/mpc8xx MPC8xx CPU specific Power On Self Test
139 - rtc Real Time Clock drivers
140 - tools Tools to build S-Record or U-Boot images, etc.
142 - cpu/74xx_7xx Files specific to Motorola MPC74xx and 7xx CPUs
143 - cpu/arm925t Files specific to ARM 925 CPUs
144 - cpu/arm926ejs Files specific to ARM 926 CPUs
145 - cpu/mpc5xx Files specific to Motorola MPC5xx CPUs
146 - cpu/mpc8xx Files specific to Motorola MPC8xx CPUs
147 - cpu/mpc824x Files specific to Motorola MPC824x CPUs
148 - cpu/mpc8260 Files specific to Motorola MPC8260 CPU
149 - cpu/mpc85xx Files specific to Motorola MPC85xx CPUs
150 - cpu/ppc4xx Files specific to IBM 4xx CPUs
153 - board/LEOX/ Files specific to boards manufactured by The LEOX team
154 - board/LEOX/elpt860 Files specific to ELPT860 boards
156 Files specific to RPXClassic boards
157 - board/RPXlite Files specific to RPXlite boards
158 - board/at91rm9200dk Files specific to AT91RM9200DK boards
159 - board/c2mon Files specific to c2mon boards
160 - board/cmi Files specific to cmi boards
161 - board/cogent Files specific to Cogent boards
162 (need further configuration)
163 Files specific to CPCIISER4 boards
164 - board/cpu86 Files specific to CPU86 boards
165 - board/cray/ Files specific to boards manufactured by Cray
166 - board/cray/L1 Files specific to L1 boards
167 - board/cu824 Files specific to CU824 boards
168 - board/ebony Files specific to IBM Ebony board
169 - board/eric Files specific to ERIC boards
170 - board/esd/ Files specific to boards manufactured by ESD
171 - board/esd/adciop Files specific to ADCIOP boards
172 - board/esd/ar405 Files specific to AR405 boards
173 - board/esd/canbt Files specific to CANBT boards
174 - board/esd/cpci405 Files specific to CPCI405 boards
175 - board/esd/cpciiser4 Files specific to CPCIISER4 boards
176 - board/esd/common Common files for ESD boards
177 - board/esd/dasa_sim Files specific to DASA_SIM boards
178 - board/esd/du405 Files specific to DU405 boards
179 - board/esd/ocrtc Files specific to OCRTC boards
180 - board/esd/pci405 Files specific to PCI405 boards
182 Files specific to ESTEEM192E boards
183 - board/etx094 Files specific to ETX_094 boards
185 Files specific to EVB64260 boards
186 - board/fads Files specific to FADS boards
187 - board/flagadm Files specific to FLAGADM boards
188 - board/gen860t Files specific to GEN860T and GEN860T_SC boards
189 - board/genietv Files specific to GENIETV boards
190 - board/gth Files specific to GTH boards
191 - board/hermes Files specific to HERMES boards
192 - board/hymod Files specific to HYMOD boards
193 - board/icu862 Files specific to ICU862 boards
194 - board/ip860 Files specific to IP860 boards
196 Files specific to Interphase4539 boards
197 - board/ivm Files specific to IVMS8/IVML24 boards
198 - board/lantec Files specific to LANTEC boards
199 - board/lwmon Files specific to LWMON boards
200 - board/Marvell Files specific to Marvell development boards
201 - board/Marvell/db64360 Files specific to db64360 board
202 - board/Marvell/db64460 Files specific to db64460 board
203 - board/mbx8xx Files specific to MBX boards
205 Files specific to MPC826xADS and PQ2FADS-ZU/VR boards
207 Files specific to MPC8540ADS boards
209 Files specific to MPC8560ADS boards
210 - board/mpl/ Files specific to boards manufactured by MPL
211 - board/mpl/common Common files for MPL boards
212 - board/mpl/pip405 Files specific to PIP405 boards
213 - board/mpl/mip405 Files specific to MIP405 boards
214 - board/mpl/vcma9 Files specific to VCMA9 boards
215 - board/musenki Files specific to MUSEKNI boards
216 - board/mvs1 Files specific to MVS1 boards
217 - board/nx823 Files specific to NX823 boards
218 - board/oxc Files specific to OXC boards
220 Files specific to OMAP 1510 Innovator boards
222 Files specific to OMAP 1610 Innovator and H2 boards
223 - board/pcippc2 Files specific to PCIPPC2/PCIPPC6 boards
224 - board/pm826 Files specific to PM826 boards
226 Files specific to PPMC8260 boards
227 - board/snmc/qs850 Files specific to QS850/823 boards
228 - board/snmc/qs860t Files specific to QS860T boards
230 Files specific to RPXsuper boards
232 Files specific to RSDproto boards
234 Files specific to Sandpoint boards
235 - board/sbc8260 Files specific to SBC8260 boards
236 - board/sacsng Files specific to SACSng boards
237 - board/siemens Files specific to boards manufactured by Siemens AG
238 - board/siemens/CCM Files specific to CCM boards
239 - board/siemens/IAD210 Files specific to IAD210 boards
240 - board/siemens/SCM Files specific to SCM boards
241 - board/siemens/pcu_e Files specific to PCU_E boards
242 - board/sixnet Files specific to SIXNET boards
243 - board/spd8xx Files specific to SPD8xxTS boards
244 - board/tqm8260 Files specific to TQM8260 boards
245 - board/tqm8xx Files specific to TQM8xxL boards
246 - board/w7o Files specific to W7O boards
248 Files specific to Walnut405 boards
249 - board/westel/ Files specific to boards manufactured by Westel Wireless
250 - board/westel/amx860 Files specific to AMX860 boards
251 - board/utx8245 Files specific to UTX8245 boards
252 - board/zpc1900 Files specific to Zephyr Engineering ZPC.1900 board
254 Software Configuration:
255 =======================
257 Configuration is usually done using C preprocessor defines; the
258 rationale behind that is to avoid dead code whenever possible.
260 There are two classes of configuration variables:
262 * Configuration _OPTIONS_:
263 These are selectable by the user and have names beginning with
266 * Configuration _SETTINGS_:
267 These depend on the hardware etc. and should not be meddled with if
268 you don't know what you're doing; they have names beginning with
271 Later we will add a configuration tool - probably similar to or even
272 identical to what's used for the Linux kernel. Right now, we have to
273 do the configuration by hand, which means creating some symbolic
274 links and editing some configuration files. We use the TQM8xxL boards
278 Selection of Processor Architecture and Board Type:
279 ---------------------------------------------------
281 For all supported boards there are ready-to-use default
282 configurations available; just type "make <board_name>_config".
284 Example: For a TQM823L module type:
289 For the Cogent platform, you need to specify the cpu type as well;
290 e.g. "make cogent_mpc8xx_config". And also configure the cogent
291 directory according to the instructions in cogent/README.
294 Configuration Options:
295 ----------------------
297 Configuration depends on the combination of board and CPU type; all
298 such information is kept in a configuration file
299 "include/configs/<board_name>.h".
301 Example: For a TQM823L module, all configuration settings are in
302 "include/configs/TQM823L.h".
305 Many of the options are named exactly as the corresponding Linux
306 kernel configuration options. The intention is to make it easier to
307 build a config tool - later.
310 The following options need to be configured:
312 - CPU Type: Define exactly one of
316 CONFIG_MPC823, CONFIG_MPC850, CONFIG_MPC855, CONFIG_MPC860
318 or CONFIG_MPC824X, CONFIG_MPC8260
334 - Board Type: Define exactly one of
336 PowerPC based boards:
337 ---------------------
339 CONFIG_ADCIOP, CONFIG_ICU862 CONFIG_RPXsuper,
340 CONFIG_ADS860, CONFIG_IP860, CONFIG_SM850,
341 CONFIG_AMX860, CONFIG_IPHASE4539, CONFIG_SPD823TS,
342 CONFIG_AR405, CONFIG_IVML24, CONFIG_SXNI855T,
343 CONFIG_BAB7xx, CONFIG_IVML24_128, CONFIG_Sandpoint8240,
344 CONFIG_CANBT, CONFIG_IVML24_256, CONFIG_Sandpoint8245,
345 CONFIG_CCM, CONFIG_IVMS8, CONFIG_TQM823L,
346 CONFIG_CPCI405, CONFIG_IVMS8_128, CONFIG_TQM850L,
347 CONFIG_CPCI4052, CONFIG_IVMS8_256, CONFIG_TQM855L,
348 CONFIG_CPCIISER4, CONFIG_LANTEC, CONFIG_TQM860L,
349 CONFIG_CPU86, CONFIG_MBX, CONFIG_TQM8260,
350 CONFIG_CRAYL1, CONFIG_MBX860T, CONFIG_TTTech,
351 CONFIG_CU824, CONFIG_MHPC, CONFIG_UTX8245,
352 CONFIG_DASA_SIM, CONFIG_MIP405, CONFIG_W7OLMC,
353 CONFIG_DU405, CONFIG_MOUSSE, CONFIG_W7OLMG,
354 CONFIG_ELPPC, CONFIG_MPC8260ADS, CONFIG_WALNUT405,
355 CONFIG_ERIC, CONFIG_MUSENKI, CONFIG_ZUMA,
356 CONFIG_ESTEEM192E, CONFIG_MVS1, CONFIG_c2mon,
357 CONFIG_ETX094, CONFIG_NX823, CONFIG_cogent_mpc8260,
358 CONFIG_EVB64260, CONFIG_OCRTC, CONFIG_cogent_mpc8xx,
359 CONFIG_FADS823, CONFIG_ORSG, CONFIG_ep8260,
360 CONFIG_FADS850SAR, CONFIG_OXC, CONFIG_gw8260,
361 CONFIG_FADS860T, CONFIG_PCI405, CONFIG_hermes,
362 CONFIG_FLAGADM, CONFIG_PCIPPC2, CONFIG_hymod,
363 CONFIG_FPS850L, CONFIG_PCIPPC6, CONFIG_lwmon,
364 CONFIG_GEN860T, CONFIG_PIP405, CONFIG_pcu_e,
365 CONFIG_GENIETV, CONFIG_PM826, CONFIG_ppmc8260,
366 CONFIG_GTH, CONFIG_RPXClassic, CONFIG_rsdproto,
367 CONFIG_IAD210, CONFIG_RPXlite, CONFIG_sbc8260,
368 CONFIG_EBONY, CONFIG_sacsng, CONFIG_FPS860L,
369 CONFIG_V37, CONFIG_ELPT860, CONFIG_CMI,
370 CONFIG_NETVIA, CONFIG_RBC823, CONFIG_ZPC1900,
371 CONFIG_MPC8540ADS, CONFIG_MPC8560ADS, CONFIG_QS850,
372 CONFIG_QS823, CONFIG_QS860T, CONFIG_DB64360,
373 CONFIG_DB64460, CONFIG_DUET_ADS
378 CONFIG_HHP_CRADLE, CONFIG_DNP1110, CONFIG_EP7312,
379 CONFIG_IMPA7, CONFIG_LART, CONFIG_LUBBOCK,
380 CONFIG_INNOVATOROMAP1510, CONFIG_INNOVATOROMAP1610,
381 CONFIG_H2_OMAP1610, CONFIG_SHANNON, CONFIG_SMDK2400,
382 CONFIG_SMDK2410, CONFIG_TRAB, CONFIG_VCMA9,
386 - CPU Module Type: (if CONFIG_COGENT is defined)
387 Define exactly one of
389 --- FIXME --- not tested yet:
390 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
391 CONFIG_CMA287_23, CONFIG_CMA287_50
393 - Motherboard Type: (if CONFIG_COGENT is defined)
394 Define exactly one of
395 CONFIG_CMA101, CONFIG_CMA102
397 - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
398 Define one or more of
401 - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
402 Define one or more of
403 CONFIG_LCD_HEARTBEAT - update a character position on
404 the lcd display every second with
407 - Board flavour: (if CONFIG_MPC8260ADS is defined)
410 CFG_8260ADS - original MPC8260ADS
411 CFG_8266ADS - MPC8266ADS
412 CFG_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR
415 - MPC824X Family Member (if CONFIG_MPC824X is defined)
416 Define exactly one of
417 CONFIG_MPC8240, CONFIG_MPC8245
419 - 8xx CPU Options: (if using an MPC8xx cpu)
420 Define one or more of
421 CONFIG_8xx_GCLK_FREQ - if get_gclk_freq() cannot work
422 e.g. if there is no 32KHz
423 reference PIT/RTC clock
425 - 859/866 CPU options: (if using a MPC859 or MPC866 CPU):
429 CFG_866_CPUCLK_DEFAULT
430 See doc/README.MPC866
434 Define this to measure the actual CPU clock instead
435 of relying on the correctness of the configured
436 values. Mostly useful for board bringup to make sure
437 the PLL is locked at the intended frequency. Note
438 that this requires a (stable) reference clock (32 kHz
441 - Linux Kernel Interface:
444 U-Boot stores all clock information in Hz
445 internally. For binary compatibility with older Linux
446 kernels (which expect the clocks passed in the
447 bd_info data to be in MHz) the environment variable
448 "clocks_in_mhz" can be defined so that U-Boot
449 converts clock data to MHZ before passing it to the
451 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
452 "clocks_in_mhz=1" is automatically included in the
455 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
457 When transfering memsize parameter to linux, some versions
458 expect it to be in bytes, others in MB.
459 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
462 Depending on board, define exactly one serial port
463 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
464 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
465 console by defining CONFIG_8xx_CONS_NONE
467 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
468 port routines must be defined elsewhere
469 (i.e. serial_init(), serial_getc(), ...)
472 Enables console device for a color framebuffer. Needs following
473 defines (cf. smiLynxEM, i8042, board/eltec/bab7xx)
474 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
476 VIDEO_HW_RECTFILL graphic chip supports
479 VIDEO_HW_BITBLT graphic chip supports
480 bit-blit (cf. smiLynxEM)
481 VIDEO_VISIBLE_COLS visible pixel columns
483 VIDEO_VISIBLE_ROWS visible pixel rows
484 VIDEO_PIXEL_SIZE bytes per pixel
485 VIDEO_DATA_FORMAT graphic data format
486 (0-5, cf. cfb_console.c)
487 VIDEO_FB_ADRS framebuffer address
488 VIDEO_KBD_INIT_FCT keyboard int fct
489 (i.e. i8042_kbd_init())
490 VIDEO_TSTC_FCT test char fct
492 VIDEO_GETC_FCT get char fct
494 CONFIG_CONSOLE_CURSOR cursor drawing on/off
495 (requires blink timer
497 CFG_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
498 CONFIG_CONSOLE_TIME display time/date info in
500 (requires CFG_CMD_DATE)
501 CONFIG_VIDEO_LOGO display Linux logo in
503 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
504 linux_logo.h for logo.
505 Requires CONFIG_VIDEO_LOGO
506 CONFIG_CONSOLE_EXTRA_INFO
507 addional board info beside
510 When CONFIG_CFB_CONSOLE is defined, video console is
511 default i/o. Serial console can be forced with
512 environment 'console=serial'.
514 When CONFIG_SILENT_CONSOLE is defined, all console
515 messages (by U-Boot and Linux!) can be silenced with
516 the "silent" environment variable. See
517 doc/README.silent for more information.
520 CONFIG_BAUDRATE - in bps
521 Select one of the baudrates listed in
522 CFG_BAUDRATE_TABLE, see below.
523 CFG_BRGCLK_PRESCALE, baudrate prescale
525 - Interrupt driven serial port input:
526 CONFIG_SERIAL_SOFTWARE_FIFO
529 Use an interrupt handler for receiving data on the
530 serial port. It also enables using hardware handshake
531 (RTS/CTS) and UART's built-in FIFO. Set the number of
532 bytes the interrupt driven input buffer should have.
534 Set to 0 to disable this feature (this is the default).
535 This will also disable hardware handshake.
537 - Console UART Number:
541 If defined internal UART1 (and not UART0) is used
542 as default U-Boot console.
544 - Boot Delay: CONFIG_BOOTDELAY - in seconds
545 Delay before automatically booting the default image;
546 set to -1 to disable autoboot.
548 See doc/README.autoboot for these options that
549 work with CONFIG_BOOTDELAY. None are required.
550 CONFIG_BOOT_RETRY_TIME
551 CONFIG_BOOT_RETRY_MIN
552 CONFIG_AUTOBOOT_KEYED
553 CONFIG_AUTOBOOT_PROMPT
554 CONFIG_AUTOBOOT_DELAY_STR
555 CONFIG_AUTOBOOT_STOP_STR
556 CONFIG_AUTOBOOT_DELAY_STR2
557 CONFIG_AUTOBOOT_STOP_STR2
558 CONFIG_ZERO_BOOTDELAY_CHECK
559 CONFIG_RESET_TO_RETRY
563 Only needed when CONFIG_BOOTDELAY is enabled;
564 define a command string that is automatically executed
565 when no character is read on the console interface
566 within "Boot Delay" after reset.
569 This can be used to pass arguments to the bootm
570 command. The value of CONFIG_BOOTARGS goes into the
571 environment value "bootargs".
573 CONFIG_RAMBOOT and CONFIG_NFSBOOT
574 The value of these goes into the environment as
575 "ramboot" and "nfsboot" respectively, and can be used
576 as a convenience, when switching between booting from
582 When this option is #defined, the existence of the
583 environment variable "preboot" will be checked
584 immediately before starting the CONFIG_BOOTDELAY
585 countdown and/or running the auto-boot command resp.
586 entering interactive mode.
588 This feature is especially useful when "preboot" is
589 automatically generated or modified. For an example
590 see the LWMON board specific code: here "preboot" is
591 modified when the user holds down a certain
592 combination of keys on the (special) keyboard when
595 - Serial Download Echo Mode:
597 If defined to 1, all characters received during a
598 serial download (using the "loads" command) are
599 echoed back. This might be needed by some terminal
600 emulations (like "cu"), but may as well just take
601 time on others. This setting #define's the initial
602 value of the "loads_echo" environment variable.
604 - Kgdb Serial Baudrate: (if CFG_CMD_KGDB is defined)
606 Select one of the baudrates listed in
607 CFG_BAUDRATE_TABLE, see below.
611 Most monitor functions can be selected (or
612 de-selected) by adjusting the definition of
613 CONFIG_COMMANDS; to select individual functions,
614 #define CONFIG_COMMANDS by "OR"ing any of the
617 #define enables commands:
618 -------------------------
619 CFG_CMD_ASKENV * ask for env variable
620 CFG_CMD_AUTOSCRIPT Autoscript Support
622 CFG_CMD_BEDBUG Include BedBug Debugger
623 CFG_CMD_BMP * BMP support
625 CFG_CMD_CACHE icache, dcache
626 CFG_CMD_CONSOLE coninfo
627 CFG_CMD_DATE * support for RTC, date/time...
628 CFG_CMD_DHCP DHCP support
629 CFG_CMD_DIAG * Diagnostics
630 CFG_CMD_DOC * Disk-On-Chip Support
631 CFG_CMD_DTT Digital Therm and Thermostat
632 CFG_CMD_ECHO * echo arguments
633 CFG_CMD_EEPROM * EEPROM read/write support
634 CFG_CMD_ELF bootelf, bootvx
636 CFG_CMD_FDC * Floppy Disk Support
637 CFG_CMD_FAT FAT partition support
638 CFG_CMD_FDOS * Dos diskette Support
639 CFG_CMD_FLASH flinfo, erase, protect
640 CFG_CMD_FPGA FPGA device initialization support
641 CFG_CMD_HWFLOW * RTS/CTS hw flow control
642 CFG_CMD_I2C * I2C serial bus support
643 CFG_CMD_IDE * IDE harddisk support
645 CFG_CMD_IMLS List all found images
646 CFG_CMD_IMMAP * IMMR dump support
647 CFG_CMD_IRQ * irqinfo
648 CFG_CMD_ITEST * Integer/string test of 2 values
649 CFG_CMD_JFFS2 * JFFS2 Support
653 CFG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
655 CFG_CMD_MISC Misc functions like sleep etc
656 CFG_CMD_MMC MMC memory mapped support
657 CFG_CMD_MII MII utility commands
658 CFG_CMD_NAND * NAND support
659 CFG_CMD_NET bootp, tftpboot, rarpboot
660 CFG_CMD_PCI * pciinfo
661 CFG_CMD_PCMCIA * PCMCIA support
662 CFG_CMD_PING * send ICMP ECHO_REQUEST to network host
663 CFG_CMD_PORTIO * Port I/O
664 CFG_CMD_REGINFO * Register dump
665 CFG_CMD_RUN run command in env variable
666 CFG_CMD_SAVES save S record dump
667 CFG_CMD_SCSI * SCSI Support
668 CFG_CMD_SDRAM * print SDRAM configuration information
669 CFG_CMD_SETGETDCR Support for DCR Register access (4xx only)
670 CFG_CMD_SPI * SPI serial bus support
671 CFG_CMD_USB * USB support
672 CFG_CMD_VFD * VFD support (TRAB)
673 CFG_CMD_BSP * Board SPecific functions
674 -----------------------------------------------
677 CFG_CMD_DFL Default configuration; at the moment
678 this is includes all commands, except
679 the ones marked with "*" in the list
682 If you don't define CONFIG_COMMANDS it defaults to
683 CFG_CMD_DFL in include/cmd_confdefs.h. A board can
684 override the default settings in the respective
687 EXAMPLE: If you want all functions except of network
688 support you can write:
690 #define CONFIG_COMMANDS (CFG_CMD_ALL & ~CFG_CMD_NET)
693 Note: Don't enable the "icache" and "dcache" commands
694 (configuration option CFG_CMD_CACHE) unless you know
695 what you (and your U-Boot users) are doing. Data
696 cache cannot be enabled on systems like the 8xx or
697 8260 (where accesses to the IMMR region must be
698 uncached), and it cannot be disabled on all other
699 systems where we (mis-) use the data cache to hold an
700 initial stack and some data.
703 XXX - this list needs to get updated!
707 If this variable is defined, it enables watchdog
708 support. There must be support in the platform specific
709 code for a watchdog. For the 8xx and 8260 CPUs, the
710 SIU Watchdog feature is enabled in the SYPCR
714 CONFIG_VERSION_VARIABLE
715 If this variable is defined, an environment variable
716 named "ver" is created by U-Boot showing the U-Boot
717 version as printed by the "version" command.
718 This variable is readonly.
722 When CFG_CMD_DATE is selected, the type of the RTC
723 has to be selected, too. Define exactly one of the
726 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
727 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
728 CONFIG_RTC_MC146818 - use MC146818 RTC
729 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
730 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
731 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
732 CONFIG_RTC_DS164x - use Dallas DS164x RTC
734 Note that if the RTC uses I2C, then the I2C interface
735 must also be configured. See I2C Support, below.
739 When CONFIG_TIMESTAMP is selected, the timestamp
740 (date and time) of an image is printed by image
741 commands like bootm or iminfo. This option is
742 automatically enabled when you select CFG_CMD_DATE .
745 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION
746 and/or CONFIG_ISO_PARTITION
748 If IDE or SCSI support is enabled (CFG_CMD_IDE or
749 CFG_CMD_SCSI) you must configure support for at least
750 one partition type as well.
753 CONFIG_IDE_RESET_ROUTINE
755 Set this to define that instead of a reset Pin, the
756 routine ide_set_reset(int idereset) will be used.
761 Set this to enable ATAPI support.
764 At the moment only there is only support for the
765 SYM53C8XX SCSI controller; define
766 CONFIG_SCSI_SYM53C8XX to enable it.
768 CFG_SCSI_MAX_LUN [8], CFG_SCSI_MAX_SCSI_ID [7] and
769 CFG_SCSI_MAX_DEVICE [CFG_SCSI_MAX_SCSI_ID *
770 CFG_SCSI_MAX_LUN] can be adjusted to define the
771 maximum numbers of LUNs, SCSI ID's and target
773 CFG_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
775 - NETWORK Support (PCI):
777 Support for Intel 8254x gigabit chips.
780 Support for Intel 82557/82559/82559ER chips.
781 Optional CONFIG_EEPRO100_SROM_WRITE enables eeprom
782 write routine for first time initialisation.
785 Support for Digital 2114x chips.
786 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
787 modem chip initialisation (KS8761/QS6611).
790 Support for National dp83815 chips.
793 Support for National dp8382[01] gigabit chips.
795 - NETWORK Support (other):
797 CONFIG_DRIVER_LAN91C96
798 Support for SMSC's LAN91C96 chips.
801 Define this to hold the physical address
802 of the LAN91C96's I/O space
804 CONFIG_LAN91C96_USE_32_BIT
805 Define this to enable 32 bit addressing
808 At the moment only the UHCI host controller is
809 supported (PIP405, MIP405); define
810 CONFIG_USB_UHCI to enable it.
811 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
812 end define CONFIG_USB_STORAGE to enable the USB
815 Supported are USB Keyboards and USB Floppy drives
819 The MMC controller on the Intel PXA is supported. To
820 enable this define CONFIG_MMC. The MMC can be
821 accessed from the boot prompt by mapping the device
822 to physical memory similar to flash. Command line is
823 enabled with CFG_CMD_MMC. The MMC driver also works with
824 the FAT fs. This is enabled with CFG_CMD_FAT.
829 Define this to enable standard (PC-Style) keyboard
833 Standard PC keyboard driver with US (is default) and
834 GERMAN key layout (switch via environment 'keymap=de') support.
835 Export function i8042_kbd_init, i8042_tstc and i8042_getc
836 for cfb_console. Supports cursor blinking.
841 Define this to enable video support (for output to
846 Enable Chips & Technologies 69000 Video chip
848 CONFIG_VIDEO_SMI_LYNXEM
849 Enable Silicon Motion SMI 712/710/810 Video chip
850 Videomode are selected via environment 'videomode' with
851 standard LiLo mode numbers.
852 Following modes are supported (* is default):
854 800x600 1024x768 1280x1024
855 256 (8bit) 303* 305 307
856 65536 (16bit) 314 317 31a
857 16,7 Mill (24bit) 315 318 31b
858 (i.e. setenv videomode 317; saveenv; reset;)
860 CONFIG_VIDEO_SED13806
861 Enable Epson SED13806 driver. This driver supports 8bpp
862 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
863 or CONFIG_VIDEO_SED13806_16BPP
868 Define this to enable a custom keyboard support.
869 This simply calls drv_keyboard_init() which must be
870 defined in your board-specific files.
871 The only board using this so far is RBC823.
873 - LCD Support: CONFIG_LCD
875 Define this to enable LCD support (for output to LCD
876 display); also select one of the supported displays
877 by defining one of these:
879 CONFIG_NEC_NL6448AC33:
881 NEC NL6448AC33-18. Active, color, single scan.
883 CONFIG_NEC_NL6448BC20
885 NEC NL6448BC20-08. 6.5", 640x480.
886 Active, color, single scan.
888 CONFIG_NEC_NL6448BC33_54
890 NEC NL6448BC33-54. 10.4", 640x480.
891 Active, color, single scan.
895 Sharp 320x240. Active, color, single scan.
896 It isn't 16x9, and I am not sure what it is.
898 CONFIG_SHARP_LQ64D341
900 Sharp LQ64D341 display, 640x480.
901 Active, color, single scan.
905 HLD1045 display, 640x480.
906 Active, color, single scan.
910 Optrex CBL50840-2 NF-FW 99 22 M5
912 Hitachi LMG6912RPFC-00T
916 320x240. Black & white.
918 Normally display is black on white background; define
919 CFG_WHITE_ON_BLACK to get it inverted.
921 - Splash Screen Support: CONFIG_SPLASH_SCREEN
923 If this option is set, the environment is checked for
924 a variable "splashimage". If found, the usual display
925 of logo, copyright and system information on the LCD
926 is supressed and the BMP image at the address
927 specified in "splashimage" is loaded instead. The
928 console is redirected to the "nulldev", too. This
929 allows for a "silent" boot where a splash screen is
930 loaded very quickly after power-on.
932 - Compression support:
935 If this option is set, support for bzip2 compressed
936 images is included. If not, only uncompressed and gzip
937 compressed images are supported.
939 NOTE: the bzip2 algorithm requires a lot of RAM, so
940 the malloc area (as defined by CFG_MALLOC_LEN) should
948 Define a default value for ethernet address to use
949 for the respective ethernet interface, in case this
950 is not determined automatically.
955 Define a default value for the IP address to use for
956 the default ethernet interface, in case this is not
957 determined through e.g. bootp.
962 Defines a default value for theIP address of a TFTP
963 server to contact when using the "tftboot" command.
965 - BOOTP Recovery Mode:
966 CONFIG_BOOTP_RANDOM_DELAY
968 If you have many targets in a network that try to
969 boot using BOOTP, you may want to avoid that all
970 systems send out BOOTP requests at precisely the same
971 moment (which would happen for instance at recovery
972 from a power failure, when all systems will try to
973 boot, thus flooding the BOOTP server. Defining
974 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
975 inserted before sending out BOOTP requests. The
976 following delays are insterted then:
978 1st BOOTP request: delay 0 ... 1 sec
979 2nd BOOTP request: delay 0 ... 2 sec
980 3rd BOOTP request: delay 0 ... 4 sec
982 BOOTP requests: delay 0 ... 8 sec
984 - DHCP Advanced Options:
987 You can fine tune the DHCP functionality by adding
988 these flags to the CONFIG_BOOTP_MASK define:
990 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
991 serverip from a DHCP server, it is possible that more
992 than one DNS serverip is offered to the client.
993 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
994 serverip will be stored in the additional environment
995 variable "dnsip2". The first DNS serverip is always
996 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
997 is added to the CONFIG_BOOTP_MASK.
999 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1000 to do a dynamic update of a DNS server. To do this, they
1001 need the hostname of the DHCP requester.
1002 If CONFIG_BOOP_SEND_HOSTNAME is added to the
1003 CONFIG_BOOTP_MASK, the content of the "hostname"
1004 environment variable is passed as option 12 to
1007 - Status LED: CONFIG_STATUS_LED
1009 Several configurations allow to display the current
1010 status using a LED. For instance, the LED will blink
1011 fast while running U-Boot code, stop blinking as
1012 soon as a reply to a BOOTP request was received, and
1013 start blinking slow once the Linux kernel is running
1014 (supported by a status LED driver in the Linux
1015 kernel). Defining CONFIG_STATUS_LED enables this
1018 - CAN Support: CONFIG_CAN_DRIVER
1020 Defining CONFIG_CAN_DRIVER enables CAN driver support
1021 on those systems that support this (optional)
1022 feature, like the TQM8xxL modules.
1024 - I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C
1026 These enable I2C serial bus commands. Defining either of
1027 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will
1028 include the appropriate I2C driver for the selected cpu.
1030 This will allow you to use i2c commands at the u-boot
1031 command line (as long as you set CFG_CMD_I2C in
1032 CONFIG_COMMANDS) and communicate with i2c based realtime
1033 clock chips. See common/cmd_i2c.c for a description of the
1034 command line interface.
1036 CONFIG_HARD_I2C selects the CPM hardware driver for I2C.
1038 CONFIG_SOFT_I2C configures u-boot to use a software (aka
1039 bit-banging) driver instead of CPM or similar hardware
1042 There are several other quantities that must also be
1043 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C.
1045 In both cases you will need to define CFG_I2C_SPEED
1046 to be the frequency (in Hz) at which you wish your i2c bus
1047 to run and CFG_I2C_SLAVE to be the address of this node (ie
1048 the cpu's i2c node address).
1050 Now, the u-boot i2c code for the mpc8xx (cpu/mpc8xx/i2c.c)
1051 sets the cpu up as a master node and so its address should
1052 therefore be cleared to 0 (See, eg, MPC823e User's Manual
1053 p.16-473). So, set CFG_I2C_SLAVE to 0.
1055 That's all that's required for CONFIG_HARD_I2C.
1057 If you use the software i2c interface (CONFIG_SOFT_I2C)
1058 then the following macros need to be defined (examples are
1059 from include/configs/lwmon.h):
1063 (Optional). Any commands necessary to enable the I2C
1064 controller or configure ports.
1066 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
1070 (Only for MPC8260 CPU). The I/O port to use (the code
1071 assumes both bits are on the same port). Valid values
1072 are 0..3 for ports A..D.
1076 The code necessary to make the I2C data line active
1077 (driven). If the data line is open collector, this
1080 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
1084 The code necessary to make the I2C data line tri-stated
1085 (inactive). If the data line is open collector, this
1088 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1092 Code that returns TRUE if the I2C data line is high,
1095 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1099 If <bit> is TRUE, sets the I2C data line high. If it
1100 is FALSE, it clears it (low).
1102 eg: #define I2C_SDA(bit) \
1103 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
1104 else immr->im_cpm.cp_pbdat &= ~PB_SDA
1108 If <bit> is TRUE, sets the I2C clock line high. If it
1109 is FALSE, it clears it (low).
1111 eg: #define I2C_SCL(bit) \
1112 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
1113 else immr->im_cpm.cp_pbdat &= ~PB_SCL
1117 This delay is invoked four times per clock cycle so this
1118 controls the rate of data transfer. The data rate thus
1119 is 1 / (I2C_DELAY * 4). Often defined to be something
1122 #define I2C_DELAY udelay(2)
1126 When a board is reset during an i2c bus transfer
1127 chips might think that the current transfer is still
1128 in progress. On some boards it is possible to access
1129 the i2c SCLK line directly, either by using the
1130 processor pin as a GPIO or by having a second pin
1131 connected to the bus. If this option is defined a
1132 custom i2c_init_board() routine in boards/xxx/board.c
1133 is run early in the boot sequence.
1135 - SPI Support: CONFIG_SPI
1137 Enables SPI driver (so far only tested with
1138 SPI EEPROM, also an instance works with Crystal A/D and
1139 D/As on the SACSng board)
1143 Enables extended (16-bit) SPI EEPROM addressing.
1144 (symmetrical to CONFIG_I2C_X)
1148 Enables a software (bit-bang) SPI driver rather than
1149 using hardware support. This is a general purpose
1150 driver that only requires three general I/O port pins
1151 (two outputs, one input) to function. If this is
1152 defined, the board configuration must define several
1153 SPI configuration items (port pins to use, etc). For
1154 an example, see include/configs/sacsng.h.
1156 - FPGA Support: CONFIG_FPGA_COUNT
1158 Specify the number of FPGA devices to support.
1162 Used to specify the types of FPGA devices. For example,
1163 #define CONFIG_FPGA CFG_XILINX_VIRTEX2
1165 CFG_FPGA_PROG_FEEDBACK
1167 Enable printing of hash marks during FPGA configuration.
1171 Enable checks on FPGA configuration interface busy
1172 status by the configuration function. This option
1173 will require a board or device specific function to
1178 If defined, a function that provides delays in the FPGA
1179 configuration driver.
1181 CFG_FPGA_CHECK_CTRLC
1182 Allow Control-C to interrupt FPGA configuration
1184 CFG_FPGA_CHECK_ERROR
1186 Check for configuration errors during FPGA bitfile
1187 loading. For example, abort during Virtex II
1188 configuration if the INIT_B line goes low (which
1189 indicated a CRC error).
1193 Maximum time to wait for the INIT_B line to deassert
1194 after PROB_B has been deasserted during a Virtex II
1195 FPGA configuration sequence. The default time is 500
1200 Maximum time to wait for BUSY to deassert during
1201 Virtex II FPGA configuration. The default is 5 mS.
1203 CFG_FPGA_WAIT_CONFIG
1205 Time to wait after FPGA configuration. The default is
1208 - Configuration Management:
1211 If defined, this string will be added to the U-Boot
1212 version information (U_BOOT_VERSION)
1214 - Vendor Parameter Protection:
1216 U-Boot considers the values of the environment
1217 variables "serial#" (Board Serial Number) and
1218 "ethaddr" (Ethernet Address) to be parameters that
1219 are set once by the board vendor / manufacturer, and
1220 protects these variables from casual modification by
1221 the user. Once set, these variables are read-only,
1222 and write or delete attempts are rejected. You can
1223 change this behviour:
1225 If CONFIG_ENV_OVERWRITE is #defined in your config
1226 file, the write protection for vendor parameters is
1227 completely disabled. Anybody can change or delete
1230 Alternatively, if you #define _both_ CONFIG_ETHADDR
1231 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
1232 ethernet address is installed in the environment,
1233 which can be changed exactly ONCE by the user. [The
1234 serial# is unaffected by this, i. e. it remains
1240 Define this variable to enable the reservation of
1241 "protected RAM", i. e. RAM which is not overwritten
1242 by U-Boot. Define CONFIG_PRAM to hold the number of
1243 kB you want to reserve for pRAM. You can overwrite
1244 this default value by defining an environment
1245 variable "pram" to the number of kB you want to
1246 reserve. Note that the board info structure will
1247 still show the full amount of RAM. If pRAM is
1248 reserved, a new environment variable "mem" will
1249 automatically be defined to hold the amount of
1250 remaining RAM in a form that can be passed as boot
1251 argument to Linux, for instance like that:
1253 setenv bootargs ... mem=\$(mem)
1256 This way you can tell Linux not to use this memory,
1257 either, which results in a memory region that will
1258 not be affected by reboots.
1260 *WARNING* If your board configuration uses automatic
1261 detection of the RAM size, you must make sure that
1262 this memory test is non-destructive. So far, the
1263 following board configurations are known to be
1266 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL,
1267 HERMES, IP860, RPXlite, LWMON, LANTEC,
1268 PCU_E, FLAGADM, TQM8260
1273 Define this variable to stop the system in case of a
1274 fatal error, so that you have to reset it manually.
1275 This is probably NOT a good idea for an embedded
1276 system where you want to system to reboot
1277 automatically as fast as possible, but it may be
1278 useful during development since you can try to debug
1279 the conditions that lead to the situation.
1281 CONFIG_NET_RETRY_COUNT
1283 This variable defines the number of retries for
1284 network operations like ARP, RARP, TFTP, or BOOTP
1285 before giving up the operation. If not defined, a
1286 default value of 5 is used.
1288 - Command Interpreter:
1291 Define this variable to enable the "hush" shell (from
1292 Busybox) as command line interpreter, thus enabling
1293 powerful command line syntax like
1294 if...then...else...fi conditionals or `&&' and '||'
1295 constructs ("shell scripts").
1297 If undefined, you get the old, much simpler behaviour
1298 with a somewhat smaller memory footprint.
1303 This defines the secondary prompt string, which is
1304 printed when the command interpreter needs more input
1305 to complete a command. Usually "> ".
1309 In the current implementation, the local variables
1310 space and global environment variables space are
1311 separated. Local variables are those you define by
1312 simply typing `name=value'. To access a local
1313 variable later on, you have write `$name' or
1314 `${name}'; to execute the contents of a variable
1315 directly type `$name' at the command prompt.
1317 Global environment variables are those you use
1318 setenv/printenv to work with. To run a command stored
1319 in such a variable, you need to use the run command,
1320 and you must not use the '$' sign to access them.
1322 To store commands and special characters in a
1323 variable, please use double quotation marks
1324 surrounding the whole text of the variable, instead
1325 of the backslashes before semicolons and special
1328 - Default Environment:
1329 CONFIG_EXTRA_ENV_SETTINGS
1331 Define this to contain any number of null terminated
1332 strings (variable = value pairs) that will be part of
1333 the default environment compiled into the boot image.
1335 For example, place something like this in your
1336 board's config file:
1338 #define CONFIG_EXTRA_ENV_SETTINGS \
1342 Warning: This method is based on knowledge about the
1343 internal format how the environment is stored by the
1344 U-Boot code. This is NOT an official, exported
1345 interface! Although it is unlikely that this format
1346 will change soon, there is no guarantee either.
1347 You better know what you are doing here.
1349 Note: overly (ab)use of the default environment is
1350 discouraged. Make sure to check other ways to preset
1351 the environment like the autoscript function or the
1354 - DataFlash Support:
1355 CONFIG_HAS_DATAFLASH
1357 Defining this option enables DataFlash features and
1358 allows to read/write in Dataflash via the standard
1361 - SystemACE Support:
1364 Adding this option adds support for Xilinx SystemACE
1365 chips attached via some sort of local bus. The address
1366 of the chip must alsh be defined in the
1367 CFG_SYSTEMACE_BASE macro. For example:
1369 #define CONFIG_SYSTEMACE
1370 #define CFG_SYSTEMACE_BASE 0xf0000000
1372 When SystemACE support is added, the "ace" device type
1373 becomes available to the fat commands, i.e. fatls.
1375 - Show boot progress:
1376 CONFIG_SHOW_BOOT_PROGRESS
1378 Defining this option allows to add some board-
1379 specific code (calling a user-provided function
1380 "show_boot_progress(int)") that enables you to show
1381 the system's boot progress on some display (for
1382 example, some LED's) on your board. At the moment,
1383 the following checkpoints are implemented:
1386 1 common/cmd_bootm.c before attempting to boot an image
1387 -1 common/cmd_bootm.c Image header has bad magic number
1388 2 common/cmd_bootm.c Image header has correct magic number
1389 -2 common/cmd_bootm.c Image header has bad checksum
1390 3 common/cmd_bootm.c Image header has correct checksum
1391 -3 common/cmd_bootm.c Image data has bad checksum
1392 4 common/cmd_bootm.c Image data has correct checksum
1393 -4 common/cmd_bootm.c Image is for unsupported architecture
1394 5 common/cmd_bootm.c Architecture check OK
1395 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone)
1396 6 common/cmd_bootm.c Image Type check OK
1397 -6 common/cmd_bootm.c gunzip uncompression error
1398 -7 common/cmd_bootm.c Unimplemented compression type
1399 7 common/cmd_bootm.c Uncompression OK
1400 -8 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone)
1401 8 common/cmd_bootm.c Image Type check OK
1402 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
1403 9 common/cmd_bootm.c Start initial ramdisk verification
1404 -10 common/cmd_bootm.c Ramdisk header has bad magic number
1405 -11 common/cmd_bootm.c Ramdisk header has bad checksum
1406 10 common/cmd_bootm.c Ramdisk header is OK
1407 -12 common/cmd_bootm.c Ramdisk data has bad checksum
1408 11 common/cmd_bootm.c Ramdisk data has correct checksum
1409 12 common/cmd_bootm.c Ramdisk verification complete, start loading
1410 -13 common/cmd_bootm.c Wrong Image Type (not PPC Linux Ramdisk)
1411 13 common/cmd_bootm.c Start multifile image verification
1412 14 common/cmd_bootm.c No initial ramdisk, no multifile, continue.
1413 15 common/cmd_bootm.c All preparation done, transferring control to OS
1415 -30 lib_ppc/board.c Fatal error, hang the system
1416 -31 post/post.c POST test failed, detected by post_output_backlog()
1417 -32 post/post.c POST test failed, detected by post_run_single()
1419 -1 common/cmd_doc.c Bad usage of "doc" command
1420 -1 common/cmd_doc.c No boot device
1421 -1 common/cmd_doc.c Unknown Chip ID on boot device
1422 -1 common/cmd_doc.c Read Error on boot device
1423 -1 common/cmd_doc.c Image header has bad magic number
1425 -1 common/cmd_ide.c Bad usage of "ide" command
1426 -1 common/cmd_ide.c No boot device
1427 -1 common/cmd_ide.c Unknown boot device
1428 -1 common/cmd_ide.c Unknown partition table
1429 -1 common/cmd_ide.c Invalid partition type
1430 -1 common/cmd_ide.c Read Error on boot device
1431 -1 common/cmd_ide.c Image header has bad magic number
1433 -1 common/cmd_nand.c Bad usage of "nand" command
1434 -1 common/cmd_nand.c No boot device
1435 -1 common/cmd_nand.c Unknown Chip ID on boot device
1436 -1 common/cmd_nand.c Read Error on boot device
1437 -1 common/cmd_nand.c Image header has bad magic number
1439 -1 common/env_common.c Environment has a bad CRC, using default
1445 [so far only for SMDK2400 and TRAB boards]
1447 - Modem support endable:
1448 CONFIG_MODEM_SUPPORT
1450 - RTS/CTS Flow control enable:
1453 - Modem debug support:
1454 CONFIG_MODEM_SUPPORT_DEBUG
1456 Enables debugging stuff (char screen[1024], dbg())
1457 for modem support. Useful only with BDI2000.
1459 - Interrupt support (PPC):
1461 There are common interrupt_init() and timer_interrupt()
1462 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
1463 for cpu specific initialization. interrupt_init_cpu()
1464 should set decrementer_count to appropriate value. If
1465 cpu resets decrementer automatically after interrupt
1466 (ppc4xx) it should set decrementer_count to zero.
1467 timer_interrupt() calls timer_interrupt_cpu() for cpu
1468 specific handling. If board has watchdog / status_led
1469 / other_activity_monitor it works automatically from
1470 general timer_interrupt().
1474 In the target system modem support is enabled when a
1475 specific key (key combination) is pressed during
1476 power-on. Otherwise U-Boot will boot normally
1477 (autoboot). The key_pressed() fuction is called from
1478 board_init(). Currently key_pressed() is a dummy
1479 function, returning 1 and thus enabling modem
1482 If there are no modem init strings in the
1483 environment, U-Boot proceed to autoboot; the
1484 previous output (banner, info printfs) will be
1487 See also: doc/README.Modem
1490 Configuration Settings:
1491 -----------------------
1493 - CFG_LONGHELP: Defined when you want long help messages included;
1494 undefine this when you're short of memory.
1496 - CFG_PROMPT: This is what U-Boot prints on the console to
1497 prompt for user input.
1499 - CFG_CBSIZE: Buffer size for input from the Console
1501 - CFG_PBSIZE: Buffer size for Console output
1503 - CFG_MAXARGS: max. Number of arguments accepted for monitor commands
1505 - CFG_BARGSIZE: Buffer size for Boot Arguments which are passed to
1506 the application (usually a Linux kernel) when it is
1509 - CFG_BAUDRATE_TABLE:
1510 List of legal baudrate settings for this board.
1512 - CFG_CONSOLE_INFO_QUIET
1513 Suppress display of console information at boot.
1515 - CFG_CONSOLE_IS_IN_ENV
1516 If the board specific function
1517 extern int overwrite_console (void);
1518 returns 1, the stdin, stderr and stdout are switched to the
1519 serial port, else the settings in the environment are used.
1521 - CFG_CONSOLE_OVERWRITE_ROUTINE
1522 Enable the call to overwrite_console().
1524 - CFG_CONSOLE_ENV_OVERWRITE
1525 Enable overwrite of previous console environment settings.
1527 - CFG_MEMTEST_START, CFG_MEMTEST_END:
1528 Begin and End addresses of the area used by the
1532 Enable an alternate, more extensive memory test.
1534 - CFG_MEMTEST_SCRATCH:
1535 Scratch address used by the alternate memory test
1536 You only need to set this if address zero isn't writeable
1538 - CFG_TFTP_LOADADDR:
1539 Default load address for network file downloads
1541 - CFG_LOADS_BAUD_CHANGE:
1542 Enable temporary baudrate change while serial download
1545 Physical start address of SDRAM. _Must_ be 0 here.
1548 Physical start address of Motherboard I/O (if using a
1552 Physical start address of Flash memory.
1555 Physical start address of boot monitor code (set by
1556 make config files to be same as the text base address
1557 (TEXT_BASE) used when linking) - same as
1558 CFG_FLASH_BASE when booting from flash.
1561 Size of memory reserved for monitor code, used to
1562 determine _at_compile_time_ (!) if the environment is
1563 embedded within the U-Boot image, or in a separate
1567 Size of DRAM reserved for malloc() use.
1570 Maximum size of memory mapped by the startup code of
1571 the Linux kernel; all data that must be processed by
1572 the Linux kernel (bd_info, boot arguments, eventually
1573 initrd image) must be put below this limit.
1575 - CFG_MAX_FLASH_BANKS:
1576 Max number of Flash memory banks
1578 - CFG_MAX_FLASH_SECT:
1579 Max number of sectors on a Flash chip
1581 - CFG_FLASH_ERASE_TOUT:
1582 Timeout for Flash erase operations (in ms)
1584 - CFG_FLASH_WRITE_TOUT:
1585 Timeout for Flash write operations (in ms)
1587 - CFG_FLASH_LOCK_TOUT
1588 Timeout for Flash set sector lock bit operation (in ms)
1590 - CFG_FLASH_UNLOCK_TOUT
1591 Timeout for Flash clear lock bits operation (in ms)
1593 - CFG_FLASH_PROTECTION
1594 If defined, hardware flash sectors protection is used
1595 instead of U-Boot software protection.
1597 - CFG_DIRECT_FLASH_TFTP:
1599 Enable TFTP transfers directly to flash memory;
1600 without this option such a download has to be
1601 performed in two steps: (1) download to RAM, and (2)
1602 copy from RAM to flash.
1604 The two-step approach is usually more reliable, since
1605 you can check if the download worked before you erase
1606 the flash, but in some situations (when sytem RAM is
1607 too limited to allow for a tempory copy of the
1608 downloaded image) this option may be very useful.
1611 Define if the flash driver uses extra elements in the
1612 common flash structure for storing flash geometry.
1614 - CFG_FLASH_CFI_DRIVER
1615 This option also enables the building of the cfi_flash driver
1616 in the drivers directory
1618 - CFG_RX_ETH_BUFFER:
1619 Defines the number of ethernet receive buffers. On some
1620 ethernet controllers it is recommended to set this value
1621 to 8 or even higher (EEPRO100 or 405 EMAC), since all
1622 buffers can be full shortly after enabling the interface
1623 on high ethernet traffic.
1624 Defaults to 4 if not defined.
1626 The following definitions that deal with the placement and management
1627 of environment data (variable area); in general, we support the
1628 following configurations:
1630 - CFG_ENV_IS_IN_FLASH:
1632 Define this if the environment is in flash memory.
1634 a) The environment occupies one whole flash sector, which is
1635 "embedded" in the text segment with the U-Boot code. This
1636 happens usually with "bottom boot sector" or "top boot
1637 sector" type flash chips, which have several smaller
1638 sectors at the start or the end. For instance, such a
1639 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
1640 such a case you would place the environment in one of the
1641 4 kB sectors - with U-Boot code before and after it. With
1642 "top boot sector" type flash chips, you would put the
1643 environment in one of the last sectors, leaving a gap
1644 between U-Boot and the environment.
1648 Offset of environment data (variable area) to the
1649 beginning of flash memory; for instance, with bottom boot
1650 type flash chips the second sector can be used: the offset
1651 for this sector is given here.
1653 CFG_ENV_OFFSET is used relative to CFG_FLASH_BASE.
1657 This is just another way to specify the start address of
1658 the flash sector containing the environment (instead of
1661 - CFG_ENV_SECT_SIZE:
1663 Size of the sector containing the environment.
1666 b) Sometimes flash chips have few, equal sized, BIG sectors.
1667 In such a case you don't want to spend a whole sector for
1672 If you use this in combination with CFG_ENV_IS_IN_FLASH
1673 and CFG_ENV_SECT_SIZE, you can specify to use only a part
1674 of this flash sector for the environment. This saves
1675 memory for the RAM copy of the environment.
1677 It may also save flash memory if you decide to use this
1678 when your environment is "embedded" within U-Boot code,
1679 since then the remainder of the flash sector could be used
1680 for U-Boot code. It should be pointed out that this is
1681 STRONGLY DISCOURAGED from a robustness point of view:
1682 updating the environment in flash makes it always
1683 necessary to erase the WHOLE sector. If something goes
1684 wrong before the contents has been restored from a copy in
1685 RAM, your target system will be dead.
1687 - CFG_ENV_ADDR_REDUND
1690 These settings describe a second storage area used to hold
1691 a redundand copy of the environment data, so that there is
1692 a valid backup copy in case there is a power failure during
1693 a "saveenv" operation.
1695 BE CAREFUL! Any changes to the flash layout, and some changes to the
1696 source code will make it necessary to adapt <board>/u-boot.lds*
1700 - CFG_ENV_IS_IN_NVRAM:
1702 Define this if you have some non-volatile memory device
1703 (NVRAM, battery buffered SRAM) which you want to use for the
1709 These two #defines are used to determin the memory area you
1710 want to use for environment. It is assumed that this memory
1711 can just be read and written to, without any special
1714 BE CAREFUL! The first access to the environment happens quite early
1715 in U-Boot initalization (when we try to get the setting of for the
1716 console baudrate). You *MUST* have mappend your NVRAM area then, or
1719 Please note that even with NVRAM we still use a copy of the
1720 environment in RAM: we could work on NVRAM directly, but we want to
1721 keep settings there always unmodified except somebody uses "saveenv"
1722 to save the current settings.
1725 - CFG_ENV_IS_IN_EEPROM:
1727 Use this if you have an EEPROM or similar serial access
1728 device and a driver for it.
1733 These two #defines specify the offset and size of the
1734 environment area within the total memory of your EEPROM.
1736 - CFG_I2C_EEPROM_ADDR:
1737 If defined, specified the chip address of the EEPROM device.
1738 The default address is zero.
1740 - CFG_EEPROM_PAGE_WRITE_BITS:
1741 If defined, the number of bits used to address bytes in a
1742 single page in the EEPROM device. A 64 byte page, for example
1743 would require six bits.
1745 - CFG_EEPROM_PAGE_WRITE_DELAY_MS:
1746 If defined, the number of milliseconds to delay between
1747 page writes. The default is zero milliseconds.
1749 - CFG_I2C_EEPROM_ADDR_LEN:
1750 The length in bytes of the EEPROM memory array address. Note
1751 that this is NOT the chip address length!
1754 The size in bytes of the EEPROM device.
1757 - CFG_ENV_IS_IN_DATAFLASH:
1759 Define this if you have a DataFlash memory device which you
1760 want to use for the environment.
1766 These three #defines specify the offset and size of the
1767 environment area within the total memory of your DataFlash placed
1768 at the specified address.
1771 - CFG_SPI_INIT_OFFSET
1773 Defines offset to the initial SPI buffer area in DPRAM. The
1774 area is used at an early stage (ROM part) if the environment
1775 is configured to reside in the SPI EEPROM: We need a 520 byte
1776 scratch DPRAM area. It is used between the two initialization
1777 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
1778 to be a good choice since it makes it far enough from the
1779 start of the data area as well as from the stack pointer.
1781 Please note that the environment is read-only as long as the monitor
1782 has been relocated to RAM and a RAM copy of the environment has been
1783 created; also, when using EEPROM you will have to use getenv_r()
1784 until then to read environment variables.
1786 The environment is protected by a CRC32 checksum. Before the monitor
1787 is relocated into RAM, as a result of a bad CRC you will be working
1788 with the compiled-in default environment - *silently*!!! [This is
1789 necessary, because the first environment variable we need is the
1790 "baudrate" setting for the console - if we have a bad CRC, we don't
1791 have any device yet where we could complain.]
1793 Note: once the monitor has been relocated, then it will complain if
1794 the default environment is used; a new CRC is computed as soon as you
1795 use the "saveenv" command to store a valid environment.
1797 - CFG_FAULT_ECHO_LINK_DOWN:
1798 Echo the inverted Ethernet link state to the fault LED.
1800 Note: If this option is active, then CFG_FAULT_MII_ADDR
1801 also needs to be defined.
1803 - CFG_FAULT_MII_ADDR:
1804 MII address of the PHY to check for the Ethernet link state.
1806 Low Level (hardware related) configuration options:
1807 ---------------------------------------------------
1809 - CFG_CACHELINE_SIZE:
1810 Cache Line Size of the CPU.
1813 Default address of the IMMR after system reset.
1815 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
1816 and RPXsuper) to be able to adjust the position of
1817 the IMMR register after a reset.
1819 - Floppy Disk Support:
1820 CFG_FDC_DRIVE_NUMBER
1822 the default drive number (default value 0)
1826 defines the spacing between fdc chipset registers
1831 defines the offset of register from address. It
1832 depends on which part of the data bus is connected to
1833 the fdc chipset. (default value 0)
1835 If CFG_ISA_IO_STRIDE CFG_ISA_IO_OFFSET and
1836 CFG_FDC_DRIVE_NUMBER are undefined, they take their
1839 if CFG_FDC_HW_INIT is defined, then the function
1840 fdc_hw_init() is called at the beginning of the FDC
1841 setup. fdc_hw_init() must be provided by the board
1842 source code. It is used to make hardware dependant
1845 - CFG_IMMR: Physical address of the Internal Memory Mapped
1846 Register; DO NOT CHANGE! (11-4)
1847 [MPC8xx systems only]
1849 - CFG_INIT_RAM_ADDR:
1851 Start address of memory area that can be used for
1852 initial data and stack; please note that this must be
1853 writable memory that is working WITHOUT special
1854 initialization, i. e. you CANNOT use normal RAM which
1855 will become available only after programming the
1856 memory controller and running certain initialization
1859 U-Boot uses the following memory types:
1860 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
1861 - MPC824X: data cache
1862 - PPC4xx: data cache
1864 - CFG_GBL_DATA_OFFSET:
1866 Offset of the initial data structure in the memory
1867 area defined by CFG_INIT_RAM_ADDR. Usually
1868 CFG_GBL_DATA_OFFSET is chosen such that the initial
1869 data is located at the end of the available space
1870 (sometimes written as (CFG_INIT_RAM_END -
1871 CFG_INIT_DATA_SIZE), and the initial stack is just
1872 below that area (growing from (CFG_INIT_RAM_ADDR +
1873 CFG_GBL_DATA_OFFSET) downward.
1876 On the MPC824X (or other systems that use the data
1877 cache for initial memory) the address chosen for
1878 CFG_INIT_RAM_ADDR is basically arbitrary - it must
1879 point to an otherwise UNUSED address space between
1880 the top of RAM and the start of the PCI space.
1882 - CFG_SIUMCR: SIU Module Configuration (11-6)
1884 - CFG_SYPCR: System Protection Control (11-9)
1886 - CFG_TBSCR: Time Base Status and Control (11-26)
1888 - CFG_PISCR: Periodic Interrupt Status and Control (11-31)
1890 - CFG_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
1892 - CFG_SCCR: System Clock and reset Control Register (15-27)
1894 - CFG_OR_TIMING_SDRAM:
1898 periodic timer for refresh
1900 - CFG_DER: Debug Event Register (37-47)
1902 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CFG_REMAP_OR_AM,
1903 CFG_PRELIM_OR_AM, CFG_OR_TIMING_FLASH, CFG_OR0_REMAP,
1904 CFG_OR0_PRELIM, CFG_BR0_PRELIM, CFG_OR1_REMAP, CFG_OR1_PRELIM,
1906 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
1908 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
1909 CFG_OR_TIMING_SDRAM, CFG_OR2_PRELIM, CFG_BR2_PRELIM,
1910 CFG_OR3_PRELIM, CFG_BR3_PRELIM:
1911 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
1913 - CFG_MAMR_PTA, CFG_MPTPR_2BK_4K, CFG_MPTPR_1BK_4K, CFG_MPTPR_2BK_8K,
1914 CFG_MPTPR_1BK_8K, CFG_MAMR_8COL, CFG_MAMR_9COL:
1915 Machine Mode Register and Memory Periodic Timer
1916 Prescaler definitions (SDRAM timing)
1918 - CFG_I2C_UCODE_PATCH, CFG_I2C_DPMEM_OFFSET [0x1FC0]:
1919 enable I2C microcode relocation patch (MPC8xx);
1920 define relocation offset in DPRAM [DSP2]
1922 - CFG_SPI_UCODE_PATCH, CFG_SPI_DPMEM_OFFSET [0x1FC0]:
1923 enable SPI microcode relocation patch (MPC8xx);
1924 define relocation offset in DPRAM [SCC4]
1927 Use OSCM clock mode on MBX8xx board. Be careful,
1928 wrong setting might damage your board. Read
1929 doc/README.MBX before setting this variable!
1931 - CFG_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
1932 Offset of the bootmode word in DPRAM used by post
1933 (Power On Self Tests). This definition overrides
1934 #define'd default value in commproc.h resp.
1937 - CFG_PCI_SLV_MEM_LOCAL, CFG_PCI_SLV_MEM_BUS, CFG_PICMR0_MASK_ATTRIB,
1938 CFG_PCI_MSTR0_LOCAL, CFG_PCIMSK0_MASK, CFG_PCI_MSTR1_LOCAL,
1939 CFG_PCIMSK1_MASK, CFG_PCI_MSTR_MEM_LOCAL, CFG_PCI_MSTR_MEM_BUS,
1940 CFG_CPU_PCI_MEM_START, CFG_PCI_MSTR_MEM_SIZE, CFG_POCMR0_MASK_ATTRIB,
1941 CFG_PCI_MSTR_MEMIO_LOCAL, CFG_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
1942 CFG_PCI_MSTR_MEMIO_SIZE, CFG_POCMR1_MASK_ATTRIB, CFG_PCI_MSTR_IO_LOCAL,
1943 CFG_PCI_MSTR_IO_BUS, CFG_CPU_PCI_IO_START, CFG_PCI_MSTR_IO_SIZE,
1944 CFG_POCMR2_MASK_ATTRIB: (MPC826x only)
1945 Overrides the default PCI memory map in cpu/mpc8260/pci.c if set.
1947 Building the Software:
1948 ======================
1950 Building U-Boot has been tested in native PPC environments (on a
1951 PowerBook G3 running LinuxPPC 2000) and in cross environments
1952 (running RedHat 6.x and 7.x Linux on x86, Solaris 2.6 on a SPARC, and
1955 If you are not using a native PPC environment, it is assumed that you
1956 have the GNU cross compiling tools available in your path and named
1957 with a prefix of "powerpc-linux-". If this is not the case, (e.g. if
1958 you are using Monta Vista's Hard Hat Linux CDK 1.2) you must change
1959 the definition of CROSS_COMPILE in Makefile. For HHL on a 4xx CPU,
1962 CROSS_COMPILE = ppc_4xx-
1965 U-Boot is intended to be simple to build. After installing the
1966 sources you must configure U-Boot for one specific board type. This
1971 where "NAME_config" is the name of one of the existing
1972 configurations; the following names are supported:
1974 ADCIOP_config GTH_config TQM850L_config
1975 ADS860_config IP860_config TQM855L_config
1976 AR405_config IVML24_config TQM860L_config
1977 CANBT_config IVMS8_config WALNUT405_config
1978 CPCI405_config LANTEC_config cogent_common_config
1979 CPCIISER4_config MBX_config cogent_mpc8260_config
1980 CU824_config MBX860T_config cogent_mpc8xx_config
1981 ESTEEM192E_config RPXlite_config hermes_config
1982 ETX094_config RPXsuper_config hymod_config
1983 FADS823_config SM850_config lwmon_config
1984 FADS850SAR_config SPD823TS_config pcu_e_config
1985 FADS860T_config SXNI855T_config rsdproto_config
1986 FPS850L_config Sandpoint8240_config sbc8260_config
1987 GENIETV_config TQM823L_config PIP405_config
1988 GEN860T_config EBONY_config FPS860L_config
1989 ELPT860_config cmi_mpc5xx_config NETVIA_config
1990 at91rm9200dk_config omap1510inn_config MPC8260ADS_config
1991 omap1610inn_config ZPC1900_config MPC8540ADS_config
1992 MPC8560ADS_config QS850_config QS823_config
1993 QS860T_config DUET_ADS_config omap1610h2_config
1995 Note: for some board special configuration names may exist; check if
1996 additional information is available from the board vendor; for
1997 instance, the TQM8xxL systems run normally at 50 MHz and use a
1998 SCC for 10baseT ethernet; there are also systems with 80 MHz
1999 CPU clock, and an optional Fast Ethernet module is available
2000 for CPU's with FEC. You can select such additional "features"
2001 when chosing the configuration, i. e.
2004 - will configure for a plain TQM860L, i. e. 50MHz, no FEC
2006 make TQM860L_FEC_config
2007 - will configure for a TQM860L at 50MHz with FEC for ethernet
2009 make TQM860L_80MHz_config
2010 - will configure for a TQM860L at 80 MHz, with normal 10baseT
2013 make TQM860L_FEC_80MHz_config
2014 - will configure for a TQM860L at 80 MHz with FEC for ethernet
2016 make TQM823L_LCD_config
2017 - will configure for a TQM823L with U-Boot console on LCD
2019 make TQM823L_LCD_80MHz_config
2020 - will configure for a TQM823L at 80 MHz with U-Boot console on LCD
2025 Finally, type "make all", and you should get some working U-Boot
2026 images ready for download to / installation on your system:
2028 - "u-boot.bin" is a raw binary image
2029 - "u-boot" is an image in ELF binary format
2030 - "u-boot.srec" is in Motorola S-Record format
2033 Please be aware that the Makefiles assume you are using GNU make, so
2034 for instance on NetBSD you might need to use "gmake" instead of
2038 If the system board that you have is not listed, then you will need
2039 to port U-Boot to your hardware platform. To do this, follow these
2042 1. Add a new configuration option for your board to the toplevel
2043 "Makefile" and to the "MAKEALL" script, using the existing
2044 entries as examples. Note that here and at many other places
2045 boards and other names are listed in alphabetical sort order. Please
2047 2. Create a new directory to hold your board specific code. Add any
2048 files you need. In your board directory, you will need at least
2049 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
2050 3. Create a new configuration file "include/configs/<board>.h" for
2052 3. If you're porting U-Boot to a new CPU, then also create a new
2053 directory to hold your CPU specific code. Add any files you need.
2054 4. Run "make <board>_config" with your new name.
2055 5. Type "make", and you should get a working "u-boot.srec" file
2056 to be installed on your target system.
2057 6. Debug and solve any problems that might arise.
2058 [Of course, this last step is much harder than it sounds.]
2061 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
2062 ==============================================================
2064 If you have modified U-Boot sources (for instance added a new board
2065 or support for new devices, a new CPU, etc.) you are expected to
2066 provide feedback to the other developers. The feedback normally takes
2067 the form of a "patch", i. e. a context diff against a certain (latest
2068 official or latest in CVS) version of U-Boot sources.
2070 But before you submit such a patch, please verify that your modifi-
2071 cation did not break existing code. At least make sure that *ALL* of
2072 the supported boards compile WITHOUT ANY compiler warnings. To do so,
2073 just run the "MAKEALL" script, which will configure and build U-Boot
2074 for ALL supported system. Be warned, this will take a while. You can
2075 select which (cross) compiler to use by passing a `CROSS_COMPILE'
2076 environment variable to the script, i. e. to use the cross tools from
2077 MontaVista's Hard Hat Linux you can type
2079 CROSS_COMPILE=ppc_8xx- MAKEALL
2081 or to build on a native PowerPC system you can type
2083 CROSS_COMPILE=' ' MAKEALL
2085 See also "U-Boot Porting Guide" below.
2088 Monitor Commands - Overview:
2089 ============================
2091 go - start application at address 'addr'
2092 run - run commands in an environment variable
2093 bootm - boot application image from memory
2094 bootp - boot image via network using BootP/TFTP protocol
2095 tftpboot- boot image via network using TFTP protocol
2096 and env variables "ipaddr" and "serverip"
2097 (and eventually "gatewayip")
2098 rarpboot- boot image via network using RARP/TFTP protocol
2099 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
2100 loads - load S-Record file over serial line
2101 loadb - load binary file over serial line (kermit mode)
2103 mm - memory modify (auto-incrementing)
2104 nm - memory modify (constant address)
2105 mw - memory write (fill)
2107 cmp - memory compare
2108 crc32 - checksum calculation
2109 imd - i2c memory display
2110 imm - i2c memory modify (auto-incrementing)
2111 inm - i2c memory modify (constant address)
2112 imw - i2c memory write (fill)
2113 icrc32 - i2c checksum calculation
2114 iprobe - probe to discover valid I2C chip addresses
2115 iloop - infinite loop on address range
2116 isdram - print SDRAM configuration information
2117 sspi - SPI utility commands
2118 base - print or set address offset
2119 printenv- print environment variables
2120 setenv - set environment variables
2121 saveenv - save environment variables to persistent storage
2122 protect - enable or disable FLASH write protection
2123 erase - erase FLASH memory
2124 flinfo - print FLASH memory information
2125 bdinfo - print Board Info structure
2126 iminfo - print header information for application image
2127 coninfo - print console devices and informations
2128 ide - IDE sub-system
2129 loop - infinite loop on address range
2130 mtest - simple RAM test
2131 icache - enable or disable instruction cache
2132 dcache - enable or disable data cache
2133 reset - Perform RESET of the CPU
2134 echo - echo args to console
2135 version - print monitor version
2136 help - print online help
2137 ? - alias for 'help'
2140 Monitor Commands - Detailed Description:
2141 ========================================
2145 For now: just type "help <command>".
2148 Environment Variables:
2149 ======================
2151 U-Boot supports user configuration using Environment Variables which
2152 can be made persistent by saving to Flash memory.
2154 Environment Variables are set using "setenv", printed using
2155 "printenv", and saved to Flash using "saveenv". Using "setenv"
2156 without a value can be used to delete a variable from the
2157 environment. As long as you don't save the environment you are
2158 working with an in-memory copy. In case the Flash area containing the
2159 environment is erased by accident, a default environment is provided.
2161 Some configuration options can be set using Environment Variables:
2163 baudrate - see CONFIG_BAUDRATE
2165 bootdelay - see CONFIG_BOOTDELAY
2167 bootcmd - see CONFIG_BOOTCOMMAND
2169 bootargs - Boot arguments when booting an RTOS image
2171 bootfile - Name of the image to load with TFTP
2173 autoload - if set to "no" (any string beginning with 'n'),
2174 "bootp" will just load perform a lookup of the
2175 configuration from the BOOTP server, but not try to
2176 load any image using TFTP
2178 autostart - if set to "yes", an image loaded using the "bootp",
2179 "rarpboot", "tftpboot" or "diskboot" commands will
2180 be automatically started (by internally calling
2183 If set to "no", a standalone image passed to the
2184 "bootm" command will be copied to the load address
2185 (and eventually uncompressed), but NOT be started.
2186 This can be used to load and uncompress arbitrary
2189 initrd_high - restrict positioning of initrd images:
2190 If this variable is not set, initrd images will be
2191 copied to the highest possible address in RAM; this
2192 is usually what you want since it allows for
2193 maximum initrd size. If for some reason you want to
2194 make sure that the initrd image is loaded below the
2195 CFG_BOOTMAPSZ limit, you can set this environment
2196 variable to a value of "no" or "off" or "0".
2197 Alternatively, you can set it to a maximum upper
2198 address to use (U-Boot will still check that it
2199 does not overwrite the U-Boot stack and data).
2201 For instance, when you have a system with 16 MB
2202 RAM, and want to reserve 4 MB from use by Linux,
2203 you can do this by adding "mem=12M" to the value of
2204 the "bootargs" variable. However, now you must make
2205 sure that the initrd image is placed in the first
2206 12 MB as well - this can be done with
2208 setenv initrd_high 00c00000
2210 If you set initrd_high to 0xFFFFFFFF, this is an
2211 indication to U-Boot that all addresses are legal
2212 for the Linux kernel, including addresses in flash
2213 memory. In this case U-Boot will NOT COPY the
2214 ramdisk at all. This may be useful to reduce the
2215 boot time on your system, but requires that this
2216 feature is supported by your Linux kernel.
2218 ipaddr - IP address; needed for tftpboot command
2220 loadaddr - Default load address for commands like "bootp",
2221 "rarpboot", "tftpboot", "loadb" or "diskboot"
2223 loads_echo - see CONFIG_LOADS_ECHO
2225 serverip - TFTP server IP address; needed for tftpboot command
2227 bootretry - see CONFIG_BOOT_RETRY_TIME
2229 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
2231 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
2234 The following environment variables may be used and automatically
2235 updated by the network boot commands ("bootp" and "rarpboot"),
2236 depending the information provided by your boot server:
2238 bootfile - see above
2239 dnsip - IP address of your Domain Name Server
2240 dnsip2 - IP address of your secondary Domain Name Server
2241 gatewayip - IP address of the Gateway (Router) to use
2242 hostname - Target hostname
2244 netmask - Subnet Mask
2245 rootpath - Pathname of the root filesystem on the NFS server
2246 serverip - see above
2249 There are two special Environment Variables:
2251 serial# - contains hardware identification information such
2252 as type string and/or serial number
2253 ethaddr - Ethernet address
2255 These variables can be set only once (usually during manufacturing of
2256 the board). U-Boot refuses to delete or overwrite these variables
2257 once they have been set once.
2260 Further special Environment Variables:
2262 ver - Contains the U-Boot version string as printed
2263 with the "version" command. This variable is
2264 readonly (see CONFIG_VERSION_VARIABLE).
2267 Please note that changes to some configuration parameters may take
2268 only effect after the next boot (yes, that's just like Windoze :-).
2271 Command Line Parsing:
2272 =====================
2274 There are two different command line parsers available with U-Boot:
2275 the old "simple" one, and the much more powerful "hush" shell:
2277 Old, simple command line parser:
2278 --------------------------------
2280 - supports environment variables (through setenv / saveenv commands)
2281 - several commands on one line, separated by ';'
2282 - variable substitution using "... $(name) ..." syntax
2283 - special characters ('$', ';') can be escaped by prefixing with '\',
2285 setenv bootcmd bootm \$(address)
2286 - You can also escape text by enclosing in single apostrophes, for example:
2287 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
2292 - similar to Bourne shell, with control structures like
2293 if...then...else...fi, for...do...done; while...do...done,
2294 until...do...done, ...
2295 - supports environment ("global") variables (through setenv / saveenv
2296 commands) and local shell variables (through standard shell syntax
2297 "name=value"); only environment variables can be used with "run"
2303 (1) If a command line (or an environment variable executed by a "run"
2304 command) contains several commands separated by semicolon, and
2305 one of these commands fails, then the remaining commands will be
2308 (2) If you execute several variables with one call to run (i. e.
2309 calling run with a list af variables as arguments), any failing
2310 command will cause "run" to terminate, i. e. the remaining
2311 variables are not executed.
2313 Note for Redundant Ethernet Interfaces:
2314 =======================================
2316 Some boards come with redundant ethernet interfaces; U-Boot supports
2317 such configurations and is capable of automatic selection of a
2318 "working" interface when needed. MAC assignment works as follows:
2320 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
2321 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
2322 "eth1addr" (=>eth1), "eth2addr", ...
2324 If the network interface stores some valid MAC address (for instance
2325 in SROM), this is used as default address if there is NO correspon-
2326 ding setting in the environment; if the corresponding environment
2327 variable is set, this overrides the settings in the card; that means:
2329 o If the SROM has a valid MAC address, and there is no address in the
2330 environment, the SROM's address is used.
2332 o If there is no valid address in the SROM, and a definition in the
2333 environment exists, then the value from the environment variable is
2336 o If both the SROM and the environment contain a MAC address, and
2337 both addresses are the same, this MAC address is used.
2339 o If both the SROM and the environment contain a MAC address, and the
2340 addresses differ, the value from the environment is used and a
2343 o If neither SROM nor the environment contain a MAC address, an error
2350 The "boot" commands of this monitor operate on "image" files which
2351 can be basicly anything, preceeded by a special header; see the
2352 definitions in include/image.h for details; basicly, the header
2353 defines the following image properties:
2355 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
2356 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
2357 LynxOS, pSOS, QNX, RTEMS, ARTOS;
2358 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, ARTOS, LynxOS).
2359 * Target CPU Architecture (Provisions for Alpha, ARM, Intel x86,
2360 IA64, MIPS, NIOS, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
2361 Currently supported: ARM, Intel x86, MIPS, NIOS, PowerPC).
2362 * Compression Type (uncompressed, gzip, bzip2)
2368 The header is marked by a special Magic Number, and both the header
2369 and the data portions of the image are secured against corruption by
2376 Although U-Boot should support any OS or standalone application
2377 easily, the main focus has always been on Linux during the design of
2380 U-Boot includes many features that so far have been part of some
2381 special "boot loader" code within the Linux kernel. Also, any
2382 "initrd" images to be used are no longer part of one big Linux image;
2383 instead, kernel and "initrd" are separate images. This implementation
2384 serves several purposes:
2386 - the same features can be used for other OS or standalone
2387 applications (for instance: using compressed images to reduce the
2388 Flash memory footprint)
2390 - it becomes much easier to port new Linux kernel versions because
2391 lots of low-level, hardware dependent stuff are done by U-Boot
2393 - the same Linux kernel image can now be used with different "initrd"
2394 images; of course this also means that different kernel images can
2395 be run with the same "initrd". This makes testing easier (you don't
2396 have to build a new "zImage.initrd" Linux image when you just
2397 change a file in your "initrd"). Also, a field-upgrade of the
2398 software is easier now.
2404 Porting Linux to U-Boot based systems:
2405 ---------------------------------------
2407 U-Boot cannot save you from doing all the necessary modifications to
2408 configure the Linux device drivers for use with your target hardware
2409 (no, we don't intend to provide a full virtual machine interface to
2412 But now you can ignore ALL boot loader code (in arch/ppc/mbxboot).
2414 Just make sure your machine specific header file (for instance
2415 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
2416 Information structure as we define in include/u-boot.h, and make
2417 sure that your definition of IMAP_ADDR uses the same value as your
2418 U-Boot configuration in CFG_IMMR.
2421 Configuring the Linux kernel:
2422 -----------------------------
2424 No specific requirements for U-Boot. Make sure you have some root
2425 device (initial ramdisk, NFS) for your target system.
2428 Building a Linux Image:
2429 -----------------------
2431 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
2432 not used. If you use recent kernel source, a new build target
2433 "uImage" will exist which automatically builds an image usable by
2434 U-Boot. Most older kernels also have support for a "pImage" target,
2435 which was introduced for our predecessor project PPCBoot and uses a
2436 100% compatible format.
2445 The "uImage" build target uses a special tool (in 'tools/mkimage') to
2446 encapsulate a compressed Linux kernel image with header information,
2447 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
2449 * build a standard "vmlinux" kernel image (in ELF binary format):
2451 * convert the kernel into a raw binary image:
2453 ${CROSS_COMPILE}-objcopy -O binary \
2454 -R .note -R .comment \
2455 -S vmlinux linux.bin
2457 * compress the binary image:
2461 * package compressed binary image for U-Boot:
2463 mkimage -A ppc -O linux -T kernel -C gzip \
2464 -a 0 -e 0 -n "Linux Kernel Image" \
2465 -d linux.bin.gz uImage
2468 The "mkimage" tool can also be used to create ramdisk images for use
2469 with U-Boot, either separated from the Linux kernel image, or
2470 combined into one file. "mkimage" encapsulates the images with a 64
2471 byte header containing information about target architecture,
2472 operating system, image type, compression method, entry points, time
2473 stamp, CRC32 checksums, etc.
2475 "mkimage" can be called in two ways: to verify existing images and
2476 print the header information, or to build new images.
2478 In the first form (with "-l" option) mkimage lists the information
2479 contained in the header of an existing U-Boot image; this includes
2480 checksum verification:
2482 tools/mkimage -l image
2483 -l ==> list image header information
2485 The second form (with "-d" option) is used to build a U-Boot image
2486 from a "data file" which is used as image payload:
2488 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
2489 -n name -d data_file image
2490 -A ==> set architecture to 'arch'
2491 -O ==> set operating system to 'os'
2492 -T ==> set image type to 'type'
2493 -C ==> set compression type 'comp'
2494 -a ==> set load address to 'addr' (hex)
2495 -e ==> set entry point to 'ep' (hex)
2496 -n ==> set image name to 'name'
2497 -d ==> use image data from 'datafile'
2499 Right now, all Linux kernels use the same load address (0x00000000),
2500 but the entry point address depends on the kernel version:
2502 - 2.2.x kernels have the entry point at 0x0000000C,
2503 - 2.3.x and later kernels have the entry point at 0x00000000.
2505 So a typical call to build a U-Boot image would read:
2507 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
2508 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
2509 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz \
2510 > examples/uImage.TQM850L
2511 Image Name: 2.4.4 kernel for TQM850L
2512 Created: Wed Jul 19 02:34:59 2000
2513 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2514 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
2515 Load Address: 0x00000000
2516 Entry Point: 0x00000000
2518 To verify the contents of the image (or check for corruption):
2520 -> tools/mkimage -l examples/uImage.TQM850L
2521 Image Name: 2.4.4 kernel for TQM850L
2522 Created: Wed Jul 19 02:34:59 2000
2523 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2524 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
2525 Load Address: 0x00000000
2526 Entry Point: 0x00000000
2528 NOTE: for embedded systems where boot time is critical you can trade
2529 speed for memory and install an UNCOMPRESSED image instead: this
2530 needs more space in Flash, but boots much faster since it does not
2531 need to be uncompressed:
2533 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz
2534 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
2535 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
2536 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux \
2537 > examples/uImage.TQM850L-uncompressed
2538 Image Name: 2.4.4 kernel for TQM850L
2539 Created: Wed Jul 19 02:34:59 2000
2540 Image Type: PowerPC Linux Kernel Image (uncompressed)
2541 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
2542 Load Address: 0x00000000
2543 Entry Point: 0x00000000
2546 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
2547 when your kernel is intended to use an initial ramdisk:
2549 -> tools/mkimage -n 'Simple Ramdisk Image' \
2550 > -A ppc -O linux -T ramdisk -C gzip \
2551 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
2552 Image Name: Simple Ramdisk Image
2553 Created: Wed Jan 12 14:01:50 2000
2554 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2555 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
2556 Load Address: 0x00000000
2557 Entry Point: 0x00000000
2560 Installing a Linux Image:
2561 -------------------------
2563 To downloading a U-Boot image over the serial (console) interface,
2564 you must convert the image to S-Record format:
2566 objcopy -I binary -O srec examples/image examples/image.srec
2568 The 'objcopy' does not understand the information in the U-Boot
2569 image header, so the resulting S-Record file will be relative to
2570 address 0x00000000. To load it to a given address, you need to
2571 specify the target address as 'offset' parameter with the 'loads'
2574 Example: install the image to address 0x40100000 (which on the
2575 TQM8xxL is in the first Flash bank):
2577 => erase 40100000 401FFFFF
2583 ## Ready for S-Record download ...
2584 ~>examples/image.srec
2585 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
2587 15989 15990 15991 15992
2588 [file transfer complete]
2590 ## Start Addr = 0x00000000
2593 You can check the success of the download using the 'iminfo' command;
2594 this includes a checksum verification so you can be sure no data
2595 corruption happened:
2599 ## Checking Image at 40100000 ...
2600 Image Name: 2.2.13 for initrd on TQM850L
2601 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2602 Data Size: 335725 Bytes = 327 kB = 0 MB
2603 Load Address: 00000000
2604 Entry Point: 0000000c
2605 Verifying Checksum ... OK
2611 The "bootm" command is used to boot an application that is stored in
2612 memory (RAM or Flash). In case of a Linux kernel image, the contents
2613 of the "bootargs" environment variable is passed to the kernel as
2614 parameters. You can check and modify this variable using the
2615 "printenv" and "setenv" commands:
2618 => printenv bootargs
2619 bootargs=root=/dev/ram
2621 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2623 => printenv bootargs
2624 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2627 ## Booting Linux kernel at 40020000 ...
2628 Image Name: 2.2.13 for NFS on TQM850L
2629 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2630 Data Size: 381681 Bytes = 372 kB = 0 MB
2631 Load Address: 00000000
2632 Entry Point: 0000000c
2633 Verifying Checksum ... OK
2634 Uncompressing Kernel Image ... OK
2635 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
2636 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2637 time_init: decrementer frequency = 187500000/60
2638 Calibrating delay loop... 49.77 BogoMIPS
2639 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
2642 If you want to boot a Linux kernel with initial ram disk, you pass
2643 the memory addresses of both the kernel and the initrd image (PPBCOOT
2644 format!) to the "bootm" command:
2646 => imi 40100000 40200000
2648 ## Checking Image at 40100000 ...
2649 Image Name: 2.2.13 for initrd on TQM850L
2650 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2651 Data Size: 335725 Bytes = 327 kB = 0 MB
2652 Load Address: 00000000
2653 Entry Point: 0000000c
2654 Verifying Checksum ... OK
2656 ## Checking Image at 40200000 ...
2657 Image Name: Simple Ramdisk Image
2658 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2659 Data Size: 566530 Bytes = 553 kB = 0 MB
2660 Load Address: 00000000
2661 Entry Point: 00000000
2662 Verifying Checksum ... OK
2664 => bootm 40100000 40200000
2665 ## Booting Linux kernel at 40100000 ...
2666 Image Name: 2.2.13 for initrd on TQM850L
2667 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2668 Data Size: 335725 Bytes = 327 kB = 0 MB
2669 Load Address: 00000000
2670 Entry Point: 0000000c
2671 Verifying Checksum ... OK
2672 Uncompressing Kernel Image ... OK
2673 ## Loading RAMDisk Image at 40200000 ...
2674 Image Name: Simple Ramdisk Image
2675 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2676 Data Size: 566530 Bytes = 553 kB = 0 MB
2677 Load Address: 00000000
2678 Entry Point: 00000000
2679 Verifying Checksum ... OK
2680 Loading Ramdisk ... OK
2681 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
2682 Boot arguments: root=/dev/ram
2683 time_init: decrementer frequency = 187500000/60
2684 Calibrating delay loop... 49.77 BogoMIPS
2686 RAMDISK: Compressed image found at block 0
2687 VFS: Mounted root (ext2 filesystem).
2691 More About U-Boot Image Types:
2692 ------------------------------
2694 U-Boot supports the following image types:
2696 "Standalone Programs" are directly runnable in the environment
2697 provided by U-Boot; it is expected that (if they behave
2698 well) you can continue to work in U-Boot after return from
2699 the Standalone Program.
2700 "OS Kernel Images" are usually images of some Embedded OS which
2701 will take over control completely. Usually these programs
2702 will install their own set of exception handlers, device
2703 drivers, set up the MMU, etc. - this means, that you cannot
2704 expect to re-enter U-Boot except by resetting the CPU.
2705 "RAMDisk Images" are more or less just data blocks, and their
2706 parameters (address, size) are passed to an OS kernel that is
2708 "Multi-File Images" contain several images, typically an OS
2709 (Linux) kernel image and one or more data images like
2710 RAMDisks. This construct is useful for instance when you want
2711 to boot over the network using BOOTP etc., where the boot
2712 server provides just a single image file, but you want to get
2713 for instance an OS kernel and a RAMDisk image.
2715 "Multi-File Images" start with a list of image sizes, each
2716 image size (in bytes) specified by an "uint32_t" in network
2717 byte order. This list is terminated by an "(uint32_t)0".
2718 Immediately after the terminating 0 follow the images, one by
2719 one, all aligned on "uint32_t" boundaries (size rounded up to
2720 a multiple of 4 bytes).
2722 "Firmware Images" are binary images containing firmware (like
2723 U-Boot or FPGA images) which usually will be programmed to
2726 "Script files" are command sequences that will be executed by
2727 U-Boot's command interpreter; this feature is especially
2728 useful when you configure U-Boot to use a real shell (hush)
2729 as command interpreter.
2735 One of the features of U-Boot is that you can dynamically load and
2736 run "standalone" applications, which can use some resources of
2737 U-Boot like console I/O functions or interrupt services.
2739 Two simple examples are included with the sources:
2744 'examples/hello_world.c' contains a small "Hello World" Demo
2745 application; it is automatically compiled when you build U-Boot.
2746 It's configured to run at address 0x00040004, so you can play with it
2750 ## Ready for S-Record download ...
2751 ~>examples/hello_world.srec
2752 1 2 3 4 5 6 7 8 9 10 11 ...
2753 [file transfer complete]
2755 ## Start Addr = 0x00040004
2757 => go 40004 Hello World! This is a test.
2758 ## Starting application at 0x00040004 ...
2769 Hit any key to exit ...
2771 ## Application terminated, rc = 0x0
2773 Another example, which demonstrates how to register a CPM interrupt
2774 handler with the U-Boot code, can be found in 'examples/timer.c'.
2775 Here, a CPM timer is set up to generate an interrupt every second.
2776 The interrupt service routine is trivial, just printing a '.'
2777 character, but this is just a demo program. The application can be
2778 controlled by the following keys:
2780 ? - print current values og the CPM Timer registers
2781 b - enable interrupts and start timer
2782 e - stop timer and disable interrupts
2783 q - quit application
2786 ## Ready for S-Record download ...
2787 ~>examples/timer.srec
2788 1 2 3 4 5 6 7 8 9 10 11 ...
2789 [file transfer complete]
2791 ## Start Addr = 0x00040004
2794 ## Starting application at 0x00040004 ...
2797 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
2800 [q, b, e, ?] Set interval 1000000 us
2803 [q, b, e, ?] ........
2804 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
2807 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
2810 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
2813 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
2815 [q, b, e, ?] ...Stopping timer
2817 [q, b, e, ?] ## Application terminated, rc = 0x0
2823 Over time, many people have reported problems when trying to use the
2824 "minicom" terminal emulation program for serial download. I (wd)
2825 consider minicom to be broken, and recommend not to use it. Under
2826 Unix, I recommend to use C-Kermit for general purpose use (and
2827 especially for kermit binary protocol download ("loadb" command), and
2828 use "cu" for S-Record download ("loads" command).
2830 Nevertheless, if you absolutely want to use it try adding this
2831 configuration to your "File transfer protocols" section:
2833 Name Program Name U/D FullScr IO-Red. Multi
2834 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
2835 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
2841 Starting at version 0.9.2, U-Boot supports NetBSD both as host
2842 (build U-Boot) and target system (boots NetBSD/mpc8xx).
2844 Building requires a cross environment; it is known to work on
2845 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
2846 need gmake since the Makefiles are not compatible with BSD make).
2847 Note that the cross-powerpc package does not install include files;
2848 attempting to build U-Boot will fail because <machine/ansi.h> is
2849 missing. This file has to be installed and patched manually:
2851 # cd /usr/pkg/cross/powerpc-netbsd/include
2853 # ln -s powerpc machine
2854 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
2855 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
2857 Native builds *don't* work due to incompatibilities between native
2858 and U-Boot include files.
2860 Booting assumes that (the first part of) the image booted is a
2861 stage-2 loader which in turn loads and then invokes the kernel
2862 proper. Loader sources will eventually appear in the NetBSD source
2863 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
2864 meantime, send mail to bruno@exet-ag.de and/or wd@denx.de for
2868 Implementation Internals:
2869 =========================
2871 The following is not intended to be a complete description of every
2872 implementation detail. However, it should help to understand the
2873 inner workings of U-Boot and make it easier to port it to custom
2877 Initial Stack, Global Data:
2878 ---------------------------
2880 The implementation of U-Boot is complicated by the fact that U-Boot
2881 starts running out of ROM (flash memory), usually without access to
2882 system RAM (because the memory controller is not initialized yet).
2883 This means that we don't have writable Data or BSS segments, and BSS
2884 is not initialized as zero. To be able to get a C environment working
2885 at all, we have to allocate at least a minimal stack. Implementation
2886 options for this are defined and restricted by the CPU used: Some CPU
2887 models provide on-chip memory (like the IMMR area on MPC8xx and
2888 MPC826x processors), on others (parts of) the data cache can be
2889 locked as (mis-) used as memory, etc.
2891 Chris Hallinan posted a good summary of these issues to the
2892 u-boot-users mailing list:
2894 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
2895 From: "Chris Hallinan" <clh@net1plus.com>
2896 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
2899 Correct me if I'm wrong, folks, but the way I understand it
2900 is this: Using DCACHE as initial RAM for Stack, etc, does not
2901 require any physical RAM backing up the cache. The cleverness
2902 is that the cache is being used as a temporary supply of
2903 necessary storage before the SDRAM controller is setup. It's
2904 beyond the scope of this list to expain the details, but you
2905 can see how this works by studying the cache architecture and
2906 operation in the architecture and processor-specific manuals.
2908 OCM is On Chip Memory, which I believe the 405GP has 4K. It
2909 is another option for the system designer to use as an
2910 initial stack/ram area prior to SDRAM being available. Either
2911 option should work for you. Using CS 4 should be fine if your
2912 board designers haven't used it for something that would
2913 cause you grief during the initial boot! It is frequently not
2916 CFG_INIT_RAM_ADDR should be somewhere that won't interfere
2917 with your processor/board/system design. The default value
2918 you will find in any recent u-boot distribution in
2919 Walnut405.h should work for you. I'd set it to a value larger
2920 than your SDRAM module. If you have a 64MB SDRAM module, set
2921 it above 400_0000. Just make sure your board has no resources
2922 that are supposed to respond to that address! That code in
2923 start.S has been around a while and should work as is when
2924 you get the config right.
2929 It is essential to remember this, since it has some impact on the C
2930 code for the initialization procedures:
2932 * Initialized global data (data segment) is read-only. Do not attempt
2935 * Do not use any unitialized global data (or implicitely initialized
2936 as zero data - BSS segment) at all - this is undefined, initiali-
2937 zation is performed later (when relocating to RAM).
2939 * Stack space is very limited. Avoid big data buffers or things like
2942 Having only the stack as writable memory limits means we cannot use
2943 normal global data to share information beween the code. But it
2944 turned out that the implementation of U-Boot can be greatly
2945 simplified by making a global data structure (gd_t) available to all
2946 functions. We could pass a pointer to this data as argument to _all_
2947 functions, but this would bloat the code. Instead we use a feature of
2948 the GCC compiler (Global Register Variables) to share the data: we
2949 place a pointer (gd) to the global data into a register which we
2950 reserve for this purpose.
2952 When choosing a register for such a purpose we are restricted by the
2953 relevant (E)ABI specifications for the current architecture, and by
2954 GCC's implementation.
2956 For PowerPC, the following registers have specific use:
2959 R3-R4: parameter passing and return values
2960 R5-R10: parameter passing
2961 R13: small data area pointer
2965 (U-Boot also uses R14 as internal GOT pointer.)
2967 ==> U-Boot will use R29 to hold a pointer to the global data
2969 Note: on PPC, we could use a static initializer (since the
2970 address of the global data structure is known at compile time),
2971 but it turned out that reserving a register results in somewhat
2972 smaller code - although the code savings are not that big (on
2973 average for all boards 752 bytes for the whole U-Boot image,
2974 624 text + 127 data).
2976 On ARM, the following registers are used:
2978 R0: function argument word/integer result
2979 R1-R3: function argument word
2981 R10: stack limit (used only if stack checking if enabled)
2982 R11: argument (frame) pointer
2983 R12: temporary workspace
2986 R15: program counter
2988 ==> U-Boot will use R8 to hold a pointer to the global data
2994 U-Boot runs in system state and uses physical addresses, i.e. the
2995 MMU is not used either for address mapping nor for memory protection.
2997 The available memory is mapped to fixed addresses using the memory
2998 controller. In this process, a contiguous block is formed for each
2999 memory type (Flash, SDRAM, SRAM), even when it consists of several
3000 physical memory banks.
3002 U-Boot is installed in the first 128 kB of the first Flash bank (on
3003 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
3004 booting and sizing and initializing DRAM, the code relocates itself
3005 to the upper end of DRAM. Immediately below the U-Boot code some
3006 memory is reserved for use by malloc() [see CFG_MALLOC_LEN
3007 configuration setting]. Below that, a structure with global Board
3008 Info data is placed, followed by the stack (growing downward).
3010 Additionally, some exception handler code is copied to the low 8 kB
3011 of DRAM (0x00000000 ... 0x00001FFF).
3013 So a typical memory configuration with 16 MB of DRAM could look like
3016 0x0000 0000 Exception Vector code
3019 0x0000 2000 Free for Application Use
3025 0x00FB FF20 Monitor Stack (Growing downward)
3026 0x00FB FFAC Board Info Data and permanent copy of global data
3027 0x00FC 0000 Malloc Arena
3030 0x00FE 0000 RAM Copy of Monitor Code
3031 ... eventually: LCD or video framebuffer
3032 ... eventually: pRAM (Protected RAM - unchanged by reset)
3033 0x00FF FFFF [End of RAM]
3036 System Initialization:
3037 ----------------------
3039 In the reset configuration, U-Boot starts at the reset entry point
3040 (on most PowerPC systens at address 0x00000100). Because of the reset
3041 configuration for CS0# this is a mirror of the onboard Flash memory.
3042 To be able to re-map memory U-Boot then jumps to its link address.
3043 To be able to implement the initialization code in C, a (small!)
3044 initial stack is set up in the internal Dual Ported RAM (in case CPUs
3045 which provide such a feature like MPC8xx or MPC8260), or in a locked
3046 part of the data cache. After that, U-Boot initializes the CPU core,
3047 the caches and the SIU.
3049 Next, all (potentially) available memory banks are mapped using a
3050 preliminary mapping. For example, we put them on 512 MB boundaries
3051 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
3052 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
3053 programmed for SDRAM access. Using the temporary configuration, a
3054 simple memory test is run that determines the size of the SDRAM
3057 When there is more than one SDRAM bank, and the banks are of
3058 different size, the largest is mapped first. For equal size, the first
3059 bank (CS2#) is mapped first. The first mapping is always for address
3060 0x00000000, with any additional banks following immediately to create
3061 contiguous memory starting from 0.
3063 Then, the monitor installs itself at the upper end of the SDRAM area
3064 and allocates memory for use by malloc() and for the global Board
3065 Info data; also, the exception vector code is copied to the low RAM
3066 pages, and the final stack is set up.
3068 Only after this relocation will you have a "normal" C environment;
3069 until that you are restricted in several ways, mostly because you are
3070 running from ROM, and because the code will have to be relocated to a
3074 U-Boot Porting Guide:
3075 ----------------------
3077 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
3081 int main (int argc, char *argv[])
3083 sighandler_t no_more_time;
3085 signal (SIGALRM, no_more_time);
3086 alarm (PROJECT_DEADLINE - toSec (3 * WEEK));
3088 if (available_money > available_manpower) {
3089 pay consultant to port U-Boot;
3093 Download latest U-Boot source;
3095 Subscribe to u-boot-users mailing list;
3098 email ("Hi, I am new to U-Boot, how do I get started?");
3102 Read the README file in the top level directory;
3103 Read http://www.denx.de/twiki/bin/view/DULG/Manual ;
3104 Read the source, Luke;
3107 if (available_money > toLocalCurrency ($2500)) {
3110 Add a lot of aggravation and time;
3113 Create your own board support subdirectory;
3115 Create your own board config file;
3119 Add / modify source code;
3123 email ("Hi, I am having problems...");
3125 Send patch file to Wolfgang;
3130 void no_more_time (int sig)
3139 All contributions to U-Boot should conform to the Linux kernel
3140 coding style; see the file "Documentation/CodingStyle" in your Linux
3141 kernel source directory.
3143 Please note that U-Boot is implemented in C (and to some small parts
3144 in Assembler); no C++ is used, so please do not use C++ style
3145 comments (//) in your code.
3147 Please also stick to the following formatting rules:
3148 - remove any trailing white space
3149 - use TAB characters for indentation, not spaces
3150 - make sure NOT to use DOS '\r\n' line feeds
3151 - do not add more than 2 empty lines to source files
3152 - do not add trailing empty lines to source files
3154 Submissions which do not conform to the standards may be returned
3155 with a request to reformat the changes.
3161 Since the number of patches for U-Boot is growing, we need to
3162 establish some rules. Submissions which do not conform to these rules
3163 may be rejected, even when they contain important and valuable stuff.
3166 When you send a patch, please include the following information with
3169 * For bug fixes: a description of the bug and how your patch fixes
3170 this bug. Please try to include a way of demonstrating that the
3171 patch actually fixes something.
3173 * For new features: a description of the feature and your
3176 * A CHANGELOG entry as plaintext (separate from the patch)
3178 * For major contributions, your entry to the CREDITS file
3180 * When you add support for a new board, don't forget to add this
3181 board to the MAKEALL script, too.
3183 * If your patch adds new configuration options, don't forget to
3184 document these in the README file.
3186 * The patch itself. If you are accessing the CVS repository use "cvs
3187 update; cvs diff -puRN"; else, use "diff -purN OLD NEW". If your
3188 version of diff does not support these options, then get the latest
3189 version of GNU diff.
3191 The current directory when running this command shall be the top
3192 level directory of the U-Boot source tree, or it's parent directory
3193 (i. e. please make sure that your patch includes sufficient
3194 directory information for the affected files).
3196 We accept patches as plain text, MIME attachments or as uuencoded
3199 * If one logical set of modifications affects or creates several
3200 files, all these changes shall be submitted in a SINGLE patch file.
3202 * Changesets that contain different, unrelated modifications shall be
3203 submitted as SEPARATE patches, one patch per changeset.
3208 * Before sending the patch, run the MAKEALL script on your patched
3209 source tree and make sure that no errors or warnings are reported
3210 for any of the boards.
3212 * Keep your modifications to the necessary minimum: A patch
3213 containing several unrelated changes or arbitrary reformats will be
3214 returned with a request to re-formatting / split it.
3216 * If you modify existing code, make sure that your new code does not
3217 add to the memory footprint of the code ;-) Small is beautiful!
3218 When adding new features, these should compile conditionally only
3219 (using #ifdef), and the resulting code with the new feature
3220 disabled must not need more memory than the old code without your
projects / platform / kernel / u-boot.git / blob