2 # (C) Copyright 2000 - 2002
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/mbx8xx Files specific to MBX boards
202 Files specific to MPC8260ADS and PQ2FADS-ZU boards
204 Files specific to MPC8540ADS boards
206 Files specific to MPC8560ADS boards
207 - board/mpl/ Files specific to boards manufactured by MPL
208 - board/mpl/common Common files for MPL boards
209 - board/mpl/pip405 Files specific to PIP405 boards
210 - board/mpl/mip405 Files specific to MIP405 boards
211 - board/mpl/vcma9 Files specific to VCMA9 boards
212 - board/musenki Files specific to MUSEKNI boards
213 - board/mvs1 Files specific to MVS1 boards
214 - board/nx823 Files specific to NX823 boards
215 - board/oxc Files specific to OXC boards
217 Files specific to OMAP 1510 Innovator boards
219 Files specific to OMAP 1610 Innovator boards
220 - board/pcippc2 Files specific to PCIPPC2/PCIPPC6 boards
221 - board/pm826 Files specific to PM826 boards
223 Files specific to PPMC8260 boards
224 - board/snmc/qs850 Files specific to QS850/823 boards
225 - board/snmc/qs860t Files specific to QS860T boards
227 Files specific to RPXsuper boards
229 Files specific to RSDproto boards
231 Files specific to Sandpoint boards
232 - board/sbc8260 Files specific to SBC8260 boards
233 - board/sacsng Files specific to SACSng boards
234 - board/siemens Files specific to boards manufactured by Siemens AG
235 - board/siemens/CCM Files specific to CCM boards
236 - board/siemens/IAD210 Files specific to IAD210 boards
237 - board/siemens/SCM Files specific to SCM boards
238 - board/siemens/pcu_e Files specific to PCU_E boards
239 - board/sixnet Files specific to SIXNET boards
240 - board/spd8xx Files specific to SPD8xxTS boards
241 - board/tqm8260 Files specific to TQM8260 boards
242 - board/tqm8xx Files specific to TQM8xxL boards
243 - board/w7o Files specific to W7O boards
245 Files specific to Walnut405 boards
246 - board/westel/ Files specific to boards manufactured by Westel Wireless
247 - board/westel/amx860 Files specific to AMX860 boards
248 - board/utx8245 Files specific to UTX8245 boards
249 - board/zpc1900 Files specific to Zephyr Engineering ZPC.1900 board
251 Software Configuration:
252 =======================
254 Configuration is usually done using C preprocessor defines; the
255 rationale behind that is to avoid dead code whenever possible.
257 There are two classes of configuration variables:
259 * Configuration _OPTIONS_:
260 These are selectable by the user and have names beginning with
263 * Configuration _SETTINGS_:
264 These depend on the hardware etc. and should not be meddled with if
265 you don't know what you're doing; they have names beginning with
268 Later we will add a configuration tool - probably similar to or even
269 identical to what's used for the Linux kernel. Right now, we have to
270 do the configuration by hand, which means creating some symbolic
271 links and editing some configuration files. We use the TQM8xxL boards
275 Selection of Processor Architecture and Board Type:
276 ---------------------------------------------------
278 For all supported boards there are ready-to-use default
279 configurations available; just type "make <board_name>_config".
281 Example: For a TQM823L module type:
286 For the Cogent platform, you need to specify the cpu type as well;
287 e.g. "make cogent_mpc8xx_config". And also configure the cogent
288 directory according to the instructions in cogent/README.
291 Configuration Options:
292 ----------------------
294 Configuration depends on the combination of board and CPU type; all
295 such information is kept in a configuration file
296 "include/configs/<board_name>.h".
298 Example: For a TQM823L module, all configuration settings are in
299 "include/configs/TQM823L.h".
302 Many of the options are named exactly as the corresponding Linux
303 kernel configuration options. The intention is to make it easier to
304 build a config tool - later.
307 The following options need to be configured:
309 - CPU Type: Define exactly one of
313 CONFIG_MPC823, CONFIG_MPC850, CONFIG_MPC855, CONFIG_MPC860
315 or CONFIG_MPC824X, CONFIG_MPC8260
331 - Board Type: Define exactly one of
333 PowerPC based boards:
334 ---------------------
336 CONFIG_ADCIOP, CONFIG_ICU862 CONFIG_RPXsuper,
337 CONFIG_ADS860, CONFIG_IP860, CONFIG_SM850,
338 CONFIG_AMX860, CONFIG_IPHASE4539, CONFIG_SPD823TS,
339 CONFIG_AR405, CONFIG_IVML24, CONFIG_SXNI855T,
340 CONFIG_BAB7xx, CONFIG_IVML24_128, CONFIG_Sandpoint8240,
341 CONFIG_CANBT, CONFIG_IVML24_256, CONFIG_Sandpoint8245,
342 CONFIG_CCM, CONFIG_IVMS8, CONFIG_TQM823L,
343 CONFIG_CPCI405, CONFIG_IVMS8_128, CONFIG_TQM850L,
344 CONFIG_CPCI4052, CONFIG_IVMS8_256, CONFIG_TQM855L,
345 CONFIG_CPCIISER4, CONFIG_LANTEC, CONFIG_TQM860L,
346 CONFIG_CPU86, CONFIG_MBX, CONFIG_TQM8260,
347 CONFIG_CRAYL1, CONFIG_MBX860T, CONFIG_TTTech,
348 CONFIG_CU824, CONFIG_MHPC, CONFIG_UTX8245,
349 CONFIG_DASA_SIM, CONFIG_MIP405, CONFIG_W7OLMC,
350 CONFIG_DU405, CONFIG_MOUSSE, CONFIG_W7OLMG,
351 CONFIG_ELPPC, CONFIG_MPC8260ADS, CONFIG_WALNUT405,
352 CONFIG_ERIC, CONFIG_MUSENKI, CONFIG_ZUMA,
353 CONFIG_ESTEEM192E, CONFIG_MVS1, CONFIG_c2mon,
354 CONFIG_ETX094, CONFIG_NX823, CONFIG_cogent_mpc8260,
355 CONFIG_EVB64260, CONFIG_OCRTC, CONFIG_cogent_mpc8xx,
356 CONFIG_FADS823, CONFIG_ORSG, CONFIG_ep8260,
357 CONFIG_FADS850SAR, CONFIG_OXC, CONFIG_gw8260,
358 CONFIG_FADS860T, CONFIG_PCI405, CONFIG_hermes,
359 CONFIG_FLAGADM, CONFIG_PCIPPC2, CONFIG_hymod,
360 CONFIG_FPS850L, CONFIG_PCIPPC6, CONFIG_lwmon,
361 CONFIG_GEN860T, CONFIG_PIP405, CONFIG_pcu_e,
362 CONFIG_GENIETV, CONFIG_PM826, CONFIG_ppmc8260,
363 CONFIG_GTH, CONFIG_RPXClassic, CONFIG_rsdproto,
364 CONFIG_IAD210, CONFIG_RPXlite, CONFIG_sbc8260,
365 CONFIG_EBONY, CONFIG_sacsng, CONFIG_FPS860L,
366 CONFIG_V37, CONFIG_ELPT860, CONFIG_CMI,
367 CONFIG_NETVIA, CONFIG_RBC823, CONFIG_ZPC1900,
368 CONFIG_MPC8540ADS, CONFIG_MPC8560ADS, CONFIG_QS850
369 CONFIG_QS823, CONFIG_QS860T
374 CONFIG_HHP_CRADLE, CONFIG_DNP1110, CONFIG_EP7312,
375 CONFIG_IMPA7, CONFIG_LART, CONFIG_LUBBOCK,
376 CONFIG_INNOVATOROMAP1510, CONFIG_INNOVATOROMAP1610
377 CONFIG_SHANNON, CONFIG_SMDK2400, CONFIG_SMDK2410,
378 CONFIG_TRAB, CONFIG_VCMA9, CONFIG_AT91RM9200DK
381 - CPU Module Type: (if CONFIG_COGENT is defined)
382 Define exactly one of
384 --- FIXME --- not tested yet:
385 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
386 CONFIG_CMA287_23, CONFIG_CMA287_50
388 - Motherboard Type: (if CONFIG_COGENT is defined)
389 Define exactly one of
390 CONFIG_CMA101, CONFIG_CMA102
392 - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
393 Define one or more of
396 - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
397 Define one or more of
398 CONFIG_LCD_HEARTBEAT - update a character position on
399 the lcd display every second with
402 - Board flavour: (if CONFIG_MPC8260ADS is defined)
405 CFG_8260ADS - original MPC8260ADS
406 CFG_8266ADS - MPC8266ADS (untested)
407 CFG_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR
410 - MPC824X Family Member (if CONFIG_MPC824X is defined)
411 Define exactly one of
412 CONFIG_MPC8240, CONFIG_MPC8245
414 - 8xx CPU Options: (if using an 8xx cpu)
415 Define one or more of
416 CONFIG_8xx_GCLK_FREQ - if get_gclk_freq() cannot work
417 e.g. if there is no 32KHz
418 reference PIT/RTC clock
420 - Linux Kernel Interface:
423 U-Boot stores all clock information in Hz
424 internally. For binary compatibility with older Linux
425 kernels (which expect the clocks passed in the
426 bd_info data to be in MHz) the environment variable
427 "clocks_in_mhz" can be defined so that U-Boot
428 converts clock data to MHZ before passing it to the
430 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
431 "clocks_in_mhz=1" is automatically included in the
434 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
436 When transfering memsize parameter to linux, some versions
437 expect it to be in bytes, others in MB.
438 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
441 Depending on board, define exactly one serial port
442 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
443 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
444 console by defining CONFIG_8xx_CONS_NONE
446 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
447 port routines must be defined elsewhere
448 (i.e. serial_init(), serial_getc(), ...)
451 Enables console device for a color framebuffer. Needs following
452 defines (cf. smiLynxEM, i8042, board/eltec/bab7xx)
453 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
455 VIDEO_HW_RECTFILL graphic chip supports
458 VIDEO_HW_BITBLT graphic chip supports
459 bit-blit (cf. smiLynxEM)
460 VIDEO_VISIBLE_COLS visible pixel columns
462 VIDEO_VISIBLE_ROWS visible pixel rows
463 VIDEO_PIXEL_SIZE bytes per pixel
464 VIDEO_DATA_FORMAT graphic data format
465 (0-5, cf. cfb_console.c)
466 VIDEO_FB_ADRS framebuffer address
467 VIDEO_KBD_INIT_FCT keyboard int fct
468 (i.e. i8042_kbd_init())
469 VIDEO_TSTC_FCT test char fct
471 VIDEO_GETC_FCT get char fct
473 CONFIG_CONSOLE_CURSOR cursor drawing on/off
474 (requires blink timer
476 CFG_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
477 CONFIG_CONSOLE_TIME display time/date info in
479 (requires CFG_CMD_DATE)
480 CONFIG_VIDEO_LOGO display Linux logo in
482 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
483 linux_logo.h for logo.
484 Requires CONFIG_VIDEO_LOGO
485 CONFIG_CONSOLE_EXTRA_INFO
486 addional board info beside
489 When CONFIG_CFB_CONSOLE is defined, video console is
490 default i/o. Serial console can be forced with
491 environment 'console=serial'.
493 When CONFIG_SILENT_CONSOLE is defined, all console
494 messages (by U-Boot and Linux!) can be silenced with
495 the "silent" environment variable. See
496 doc/README.silent for more information.
499 CONFIG_BAUDRATE - in bps
500 Select one of the baudrates listed in
501 CFG_BAUDRATE_TABLE, see below.
502 CFG_BRGCLK_PRESCALE, baudrate prescale
504 - Interrupt driven serial port input:
505 CONFIG_SERIAL_SOFTWARE_FIFO
508 Use an interrupt handler for receiving data on the
509 serial port. It also enables using hardware handshake
510 (RTS/CTS) and UART's built-in FIFO. Set the number of
511 bytes the interrupt driven input buffer should have.
513 Set to 0 to disable this feature (this is the default).
514 This will also disable hardware handshake.
516 - Console UART Number:
520 If defined internal UART1 (and not UART0) is used
521 as default U-Boot console.
523 - Boot Delay: CONFIG_BOOTDELAY - in seconds
524 Delay before automatically booting the default image;
525 set to -1 to disable autoboot.
527 See doc/README.autoboot for these options that
528 work with CONFIG_BOOTDELAY. None are required.
529 CONFIG_BOOT_RETRY_TIME
530 CONFIG_BOOT_RETRY_MIN
531 CONFIG_AUTOBOOT_KEYED
532 CONFIG_AUTOBOOT_PROMPT
533 CONFIG_AUTOBOOT_DELAY_STR
534 CONFIG_AUTOBOOT_STOP_STR
535 CONFIG_AUTOBOOT_DELAY_STR2
536 CONFIG_AUTOBOOT_STOP_STR2
537 CONFIG_ZERO_BOOTDELAY_CHECK
538 CONFIG_RESET_TO_RETRY
542 Only needed when CONFIG_BOOTDELAY is enabled;
543 define a command string that is automatically executed
544 when no character is read on the console interface
545 within "Boot Delay" after reset.
548 This can be used to pass arguments to the bootm
549 command. The value of CONFIG_BOOTARGS goes into the
550 environment value "bootargs".
552 CONFIG_RAMBOOT and CONFIG_NFSBOOT
553 The value of these goes into the environment as
554 "ramboot" and "nfsboot" respectively, and can be used
555 as a convenience, when switching between booting from
561 When this option is #defined, the existence of the
562 environment variable "preboot" will be checked
563 immediately before starting the CONFIG_BOOTDELAY
564 countdown and/or running the auto-boot command resp.
565 entering interactive mode.
567 This feature is especially useful when "preboot" is
568 automatically generated or modified. For an example
569 see the LWMON board specific code: here "preboot" is
570 modified when the user holds down a certain
571 combination of keys on the (special) keyboard when
574 - Serial Download Echo Mode:
576 If defined to 1, all characters received during a
577 serial download (using the "loads" command) are
578 echoed back. This might be needed by some terminal
579 emulations (like "cu"), but may as well just take
580 time on others. This setting #define's the initial
581 value of the "loads_echo" environment variable.
583 - Kgdb Serial Baudrate: (if CFG_CMD_KGDB is defined)
585 Select one of the baudrates listed in
586 CFG_BAUDRATE_TABLE, see below.
590 Most monitor functions can be selected (or
591 de-selected) by adjusting the definition of
592 CONFIG_COMMANDS; to select individual functions,
593 #define CONFIG_COMMANDS by "OR"ing any of the
596 #define enables commands:
597 -------------------------
598 CFG_CMD_ASKENV * ask for env variable
599 CFG_CMD_AUTOSCRIPT Autoscript Support
601 CFG_CMD_BEDBUG Include BedBug Debugger
602 CFG_CMD_BMP * BMP support
604 CFG_CMD_CACHE icache, dcache
605 CFG_CMD_CONSOLE coninfo
606 CFG_CMD_DATE * support for RTC, date/time...
607 CFG_CMD_DHCP DHCP support
608 CFG_CMD_DIAG * Diagnostics
609 CFG_CMD_DOC * Disk-On-Chip Support
610 CFG_CMD_DTT Digital Therm and Thermostat
611 CFG_CMD_ECHO * echo arguments
612 CFG_CMD_EEPROM * EEPROM read/write support
613 CFG_CMD_ELF bootelf, bootvx
615 CFG_CMD_FDC * Floppy Disk Support
616 CFG_CMD_FAT FAT partition support
617 CFG_CMD_FDOS * Dos diskette Support
618 CFG_CMD_FLASH flinfo, erase, protect
619 CFG_CMD_FPGA FPGA device initialization support
620 CFG_CMD_HWFLOW * RTS/CTS hw flow control
621 CFG_CMD_I2C * I2C serial bus support
622 CFG_CMD_IDE * IDE harddisk support
624 CFG_CMD_IMLS List all found images
625 CFG_CMD_IMMAP * IMMR dump support
626 CFG_CMD_IRQ * irqinfo
627 CFG_CMD_JFFS2 * JFFS2 Support
631 CFG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
633 CFG_CMD_MISC Misc functions like sleep etc
634 CFG_CMD_MMC MMC memory mapped support
635 CFG_CMD_MII MII utility commands
636 CFG_CMD_NAND * NAND support
637 CFG_CMD_NET bootp, tftpboot, rarpboot
638 CFG_CMD_PCI * pciinfo
639 CFG_CMD_PCMCIA * PCMCIA support
640 CFG_CMD_PING * send ICMP ECHO_REQUEST to network host
641 CFG_CMD_PORTIO * Port I/O
642 CFG_CMD_REGINFO * Register dump
643 CFG_CMD_RUN run command in env variable
644 CFG_CMD_SAVES save S record dump
645 CFG_CMD_SCSI * SCSI Support
646 CFG_CMD_SDRAM * print SDRAM configuration information
647 CFG_CMD_SETGETDCR Support for DCR Register access (4xx only)
648 CFG_CMD_SPI * SPI serial bus support
649 CFG_CMD_USB * USB support
650 CFG_CMD_VFD * VFD support (TRAB)
651 CFG_CMD_BSP * Board SPecific functions
652 -----------------------------------------------
655 CFG_CMD_DFL Default configuration; at the moment
656 this is includes all commands, except
657 the ones marked with "*" in the list
660 If you don't define CONFIG_COMMANDS it defaults to
661 CFG_CMD_DFL in include/cmd_confdefs.h. A board can
662 override the default settings in the respective
665 EXAMPLE: If you want all functions except of network
666 support you can write:
668 #define CONFIG_COMMANDS (CFG_CMD_ALL & ~CFG_CMD_NET)
671 Note: Don't enable the "icache" and "dcache" commands
672 (configuration option CFG_CMD_CACHE) unless you know
673 what you (and your U-Boot users) are doing. Data
674 cache cannot be enabled on systems like the 8xx or
675 8260 (where accesses to the IMMR region must be
676 uncached), and it cannot be disabled on all other
677 systems where we (mis-) use the data cache to hold an
678 initial stack and some data.
681 XXX - this list needs to get updated!
685 If this variable is defined, it enables watchdog
686 support. There must be support in the platform specific
687 code for a watchdog. For the 8xx and 8260 CPUs, the
688 SIU Watchdog feature is enabled in the SYPCR
692 CONFIG_VERSION_VARIABLE
693 If this variable is defined, an environment variable
694 named "ver" is created by U-Boot showing the U-Boot
695 version as printed by the "version" command.
696 This variable is readonly.
700 When CFG_CMD_DATE is selected, the type of the RTC
701 has to be selected, too. Define exactly one of the
704 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
705 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
706 CONFIG_RTC_MC146818 - use MC146818 RTC
707 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
708 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
709 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
710 CONFIG_RTC_DS164x - use Dallas DS164x RTC
712 Note that if the RTC uses I2C, then the I2C interface
713 must also be configured. See I2C Support, below.
717 When CONFIG_TIMESTAMP is selected, the timestamp
718 (date and time) of an image is printed by image
719 commands like bootm or iminfo. This option is
720 automatically enabled when you select CFG_CMD_DATE .
723 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION
724 and/or CONFIG_ISO_PARTITION
726 If IDE or SCSI support is enabled (CFG_CMD_IDE or
727 CFG_CMD_SCSI) you must configure support for at least
728 one partition type as well.
731 CONFIG_IDE_RESET_ROUTINE
733 Set this to define that instead of a reset Pin, the
734 routine ide_set_reset(int idereset) will be used.
739 Set this to enable ATAPI support.
742 At the moment only there is only support for the
743 SYM53C8XX SCSI controller; define
744 CONFIG_SCSI_SYM53C8XX to enable it.
746 CFG_SCSI_MAX_LUN [8], CFG_SCSI_MAX_SCSI_ID [7] and
747 CFG_SCSI_MAX_DEVICE [CFG_SCSI_MAX_SCSI_ID *
748 CFG_SCSI_MAX_LUN] can be adjusted to define the
749 maximum numbers of LUNs, SCSI ID's and target
751 CFG_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
753 - NETWORK Support (PCI):
755 Support for Intel 8254x gigabit chips.
758 Support for Intel 82557/82559/82559ER chips.
759 Optional CONFIG_EEPRO100_SROM_WRITE enables eeprom
760 write routine for first time initialisation.
763 Support for Digital 2114x chips.
764 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
765 modem chip initialisation (KS8761/QS6611).
768 Support for National dp83815 chips.
771 Support for National dp8382[01] gigabit chips.
773 - NETWORK Support (other):
775 CONFIG_DRIVER_LAN91C96
776 Support for SMSC's LAN91C96 chips.
779 Define this to hold the physical address
780 of the LAN91C96's I/O space
782 CONFIG_LAN91C96_USE_32_BIT
783 Define this to enable 32 bit addressing
786 At the moment only the UHCI host controller is
787 supported (PIP405, MIP405); define
788 CONFIG_USB_UHCI to enable it.
789 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
790 end define CONFIG_USB_STORAGE to enable the USB
793 Supported are USB Keyboards and USB Floppy drives
797 The MMC controller on the Intel PXA is supported. To
798 enable this define CONFIG_MMC. The MMC can be
799 accessed from the boot prompt by mapping the device
800 to physical memory similar to flash. Command line is
801 enabled with CFG_CMD_MMC. The MMC driver also works with
802 the FAT fs. This is enabled with CFG_CMD_FAT.
807 Define this to enable standard (PC-Style) keyboard
811 Standard PC keyboard driver with US (is default) and
812 GERMAN key layout (switch via environment 'keymap=de') support.
813 Export function i8042_kbd_init, i8042_tstc and i8042_getc
814 for cfb_console. Supports cursor blinking.
819 Define this to enable video support (for output to
824 Enable Chips & Technologies 69000 Video chip
826 CONFIG_VIDEO_SMI_LYNXEM
827 Enable Silicon Motion SMI 712/710/810 Video chip
828 Videomode are selected via environment 'videomode' with
829 standard LiLo mode numbers.
830 Following modes are supported (* is default):
832 800x600 1024x768 1280x1024
833 256 (8bit) 303* 305 307
834 65536 (16bit) 314 317 31a
835 16,7 Mill (24bit) 315 318 31b
836 (i.e. setenv videomode 317; saveenv; reset;)
838 CONFIG_VIDEO_SED13806
839 Enable Epson SED13806 driver. This driver supports 8bpp
840 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
841 or CONFIG_VIDEO_SED13806_16BPP
846 Define this to enable a custom keyboard support.
847 This simply calls drv_keyboard_init() which must be
848 defined in your board-specific files.
849 The only board using this so far is RBC823.
851 - LCD Support: CONFIG_LCD
853 Define this to enable LCD support (for output to LCD
854 display); also select one of the supported displays
855 by defining one of these:
857 CONFIG_NEC_NL6448AC33:
859 NEC NL6448AC33-18. Active, color, single scan.
861 CONFIG_NEC_NL6448BC20
863 NEC NL6448BC20-08. 6.5", 640x480.
864 Active, color, single scan.
866 CONFIG_NEC_NL6448BC33_54
868 NEC NL6448BC33-54. 10.4", 640x480.
869 Active, color, single scan.
873 Sharp 320x240. Active, color, single scan.
874 It isn't 16x9, and I am not sure what it is.
876 CONFIG_SHARP_LQ64D341
878 Sharp LQ64D341 display, 640x480.
879 Active, color, single scan.
883 HLD1045 display, 640x480.
884 Active, color, single scan.
888 Optrex CBL50840-2 NF-FW 99 22 M5
890 Hitachi LMG6912RPFC-00T
894 320x240. Black & white.
896 Normally display is black on white background; define
897 CFG_WHITE_ON_BLACK to get it inverted.
899 - Splash Screen Support: CONFIG_SPLASH_SCREEN
901 If this option is set, the environment is checked for
902 a variable "splashimage". If found, the usual display
903 of logo, copyright and system information on the LCD
904 is supressed and the BMP image at the address
905 specified in "splashimage" is loaded instead. The
906 console is redirected to the "nulldev", too. This
907 allows for a "silent" boot where a splash screen is
908 loaded very quickly after power-on.
910 - Compression support:
913 If this option is set, support for bzip2 compressed
914 images is included. If not, only uncompressed and gzip
915 compressed images are supported.
917 NOTE: the bzip2 algorithm requires a lot of RAM, so
918 the malloc area (as defined by CFG_MALLOC_LEN) should
926 Define a default value for ethernet address to use
927 for the respective ethernet interface, in case this
928 is not determined automatically.
933 Define a default value for the IP address to use for
934 the default ethernet interface, in case this is not
935 determined through e.g. bootp.
940 Defines a default value for theIP address of a TFTP
941 server to contact when using the "tftboot" command.
943 - BOOTP Recovery Mode:
944 CONFIG_BOOTP_RANDOM_DELAY
946 If you have many targets in a network that try to
947 boot using BOOTP, you may want to avoid that all
948 systems send out BOOTP requests at precisely the same
949 moment (which would happen for instance at recovery
950 from a power failure, when all systems will try to
951 boot, thus flooding the BOOTP server. Defining
952 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
953 inserted before sending out BOOTP requests. The
954 following delays are insterted then:
956 1st BOOTP request: delay 0 ... 1 sec
957 2nd BOOTP request: delay 0 ... 2 sec
958 3rd BOOTP request: delay 0 ... 4 sec
960 BOOTP requests: delay 0 ... 8 sec
962 - DHCP Advanced Options:
965 You can fine tune the DHCP functionality by adding
966 these flags to the CONFIG_BOOTP_MASK define:
968 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
969 serverip from a DHCP server, it is possible that more
970 than one DNS serverip is offered to the client.
971 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
972 serverip will be stored in the additional environment
973 variable "dnsip2". The first DNS serverip is always
974 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
975 is added to the CONFIG_BOOTP_MASK.
977 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
978 to do a dynamic update of a DNS server. To do this, they
979 need the hostname of the DHCP requester.
980 If CONFIG_BOOP_SEND_HOSTNAME is added to the
981 CONFIG_BOOTP_MASK, the content of the "hostname"
982 environment variable is passed as option 12 to
985 - Status LED: CONFIG_STATUS_LED
987 Several configurations allow to display the current
988 status using a LED. For instance, the LED will blink
989 fast while running U-Boot code, stop blinking as
990 soon as a reply to a BOOTP request was received, and
991 start blinking slow once the Linux kernel is running
992 (supported by a status LED driver in the Linux
993 kernel). Defining CONFIG_STATUS_LED enables this
996 - CAN Support: CONFIG_CAN_DRIVER
998 Defining CONFIG_CAN_DRIVER enables CAN driver support
999 on those systems that support this (optional)
1000 feature, like the TQM8xxL modules.
1002 - I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C
1004 These enable I2C serial bus commands. Defining either of
1005 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will
1006 include the appropriate I2C driver for the selected cpu.
1008 This will allow you to use i2c commands at the u-boot
1009 command line (as long as you set CFG_CMD_I2C in
1010 CONFIG_COMMANDS) and communicate with i2c based realtime
1011 clock chips. See common/cmd_i2c.c for a description of the
1012 command line interface.
1014 CONFIG_HARD_I2C selects the CPM hardware driver for I2C.
1016 CONFIG_SOFT_I2C configures u-boot to use a software (aka
1017 bit-banging) driver instead of CPM or similar hardware
1020 There are several other quantities that must also be
1021 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C.
1023 In both cases you will need to define CFG_I2C_SPEED
1024 to be the frequency (in Hz) at which you wish your i2c bus
1025 to run and CFG_I2C_SLAVE to be the address of this node (ie
1026 the cpu's i2c node address).
1028 Now, the u-boot i2c code for the mpc8xx (cpu/mpc8xx/i2c.c)
1029 sets the cpu up as a master node and so its address should
1030 therefore be cleared to 0 (See, eg, MPC823e User's Manual
1031 p.16-473). So, set CFG_I2C_SLAVE to 0.
1033 That's all that's required for CONFIG_HARD_I2C.
1035 If you use the software i2c interface (CONFIG_SOFT_I2C)
1036 then the following macros need to be defined (examples are
1037 from include/configs/lwmon.h):
1041 (Optional). Any commands necessary to enable the I2C
1042 controller or configure ports.
1044 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
1048 (Only for MPC8260 CPU). The I/O port to use (the code
1049 assumes both bits are on the same port). Valid values
1050 are 0..3 for ports A..D.
1054 The code necessary to make the I2C data line active
1055 (driven). If the data line is open collector, this
1058 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
1062 The code necessary to make the I2C data line tri-stated
1063 (inactive). If the data line is open collector, this
1066 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1070 Code that returns TRUE if the I2C data line is high,
1073 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1077 If <bit> is TRUE, sets the I2C data line high. If it
1078 is FALSE, it clears it (low).
1080 eg: #define I2C_SDA(bit) \
1081 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
1082 else immr->im_cpm.cp_pbdat &= ~PB_SDA
1086 If <bit> is TRUE, sets the I2C clock line high. If it
1087 is FALSE, it clears it (low).
1089 eg: #define I2C_SCL(bit) \
1090 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
1091 else immr->im_cpm.cp_pbdat &= ~PB_SCL
1095 This delay is invoked four times per clock cycle so this
1096 controls the rate of data transfer. The data rate thus
1097 is 1 / (I2C_DELAY * 4). Often defined to be something
1100 #define I2C_DELAY udelay(2)
1104 When a board is reset during an i2c bus transfer
1105 chips might think that the current transfer is still
1106 in progress. On some boards it is possible to access
1107 the i2c SCLK line directly, either by using the
1108 processor pin as a GPIO or by having a second pin
1109 connected to the bus. If this option is defined a
1110 custom i2c_init_board() routine in boards/xxx/board.c
1111 is run early in the boot sequence.
1113 - SPI Support: CONFIG_SPI
1115 Enables SPI driver (so far only tested with
1116 SPI EEPROM, also an instance works with Crystal A/D and
1117 D/As on the SACSng board)
1121 Enables extended (16-bit) SPI EEPROM addressing.
1122 (symmetrical to CONFIG_I2C_X)
1126 Enables a software (bit-bang) SPI driver rather than
1127 using hardware support. This is a general purpose
1128 driver that only requires three general I/O port pins
1129 (two outputs, one input) to function. If this is
1130 defined, the board configuration must define several
1131 SPI configuration items (port pins to use, etc). For
1132 an example, see include/configs/sacsng.h.
1134 - FPGA Support: CONFIG_FPGA_COUNT
1136 Specify the number of FPGA devices to support.
1140 Used to specify the types of FPGA devices. For
1142 #define CONFIG_FPGA CFG_XILINX_VIRTEX2
1144 CFG_FPGA_PROG_FEEDBACK
1146 Enable printing of hash marks during FPGA
1151 Enable checks on FPGA configuration interface busy
1152 status by the configuration function. This option
1153 will require a board or device specific function to
1158 If defined, a function that provides delays in the
1159 FPGA configuration driver.
1161 CFG_FPGA_CHECK_CTRLC
1163 Allow Control-C to interrupt FPGA configuration
1165 CFG_FPGA_CHECK_ERROR
1167 Check for configuration errors during FPGA bitfile
1168 loading. For example, abort during Virtex II
1169 configuration if the INIT_B line goes low (which
1170 indicated a CRC error).
1174 Maximum time to wait for the INIT_B line to deassert
1175 after PROB_B has been deasserted during a Virtex II
1176 FPGA configuration sequence. The default time is 500 mS.
1180 Maximum time to wait for BUSY to deassert during
1181 Virtex II FPGA configuration. The default is 5 mS.
1183 CFG_FPGA_WAIT_CONFIG
1185 Time to wait after FPGA configuration. The default is
1188 - FPGA Support: CONFIG_FPGA_COUNT
1190 Specify the number of FPGA devices to support.
1194 Used to specify the types of FPGA devices. For example,
1195 #define CONFIG_FPGA CFG_XILINX_VIRTEX2
1197 CFG_FPGA_PROG_FEEDBACK
1199 Enable printing of hash marks during FPGA configuration.
1203 Enable checks on FPGA configuration interface busy
1204 status by the configuration function. This option
1205 will require a board or device specific function to
1210 If defined, a function that provides delays in the FPGA
1211 configuration driver.
1213 CFG_FPGA_CHECK_CTRLC
1214 Allow Control-C to interrupt FPGA configuration
1216 CFG_FPGA_CHECK_ERROR
1218 Check for configuration errors during FPGA bitfile
1219 loading. For example, abort during Virtex II
1220 configuration if the INIT_B line goes low (which
1221 indicated a CRC error).
1225 Maximum time to wait for the INIT_B line to deassert
1226 after PROB_B has been deasserted during a Virtex II
1227 FPGA configuration sequence. The default time is 500
1232 Maximum time to wait for BUSY to deassert during
1233 Virtex II FPGA configuration. The default is 5 mS.
1235 CFG_FPGA_WAIT_CONFIG
1237 Time to wait after FPGA configuration. The default is
1240 - Configuration Management:
1243 If defined, this string will be added to the U-Boot
1244 version information (U_BOOT_VERSION)
1246 - Vendor Parameter Protection:
1248 U-Boot considers the values of the environment
1249 variables "serial#" (Board Serial Number) and
1250 "ethaddr" (Ethernet Address) to be parameters that
1251 are set once by the board vendor / manufacturer, and
1252 protects these variables from casual modification by
1253 the user. Once set, these variables are read-only,
1254 and write or delete attempts are rejected. You can
1255 change this behviour:
1257 If CONFIG_ENV_OVERWRITE is #defined in your config
1258 file, the write protection for vendor parameters is
1259 completely disabled. Anybody can change or delete
1262 Alternatively, if you #define _both_ CONFIG_ETHADDR
1263 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
1264 ethernet address is installed in the environment,
1265 which can be changed exactly ONCE by the user. [The
1266 serial# is unaffected by this, i. e. it remains
1272 Define this variable to enable the reservation of
1273 "protected RAM", i. e. RAM which is not overwritten
1274 by U-Boot. Define CONFIG_PRAM to hold the number of
1275 kB you want to reserve for pRAM. You can overwrite
1276 this default value by defining an environment
1277 variable "pram" to the number of kB you want to
1278 reserve. Note that the board info structure will
1279 still show the full amount of RAM. If pRAM is
1280 reserved, a new environment variable "mem" will
1281 automatically be defined to hold the amount of
1282 remaining RAM in a form that can be passed as boot
1283 argument to Linux, for instance like that:
1285 setenv bootargs ... mem=\$(mem)
1288 This way you can tell Linux not to use this memory,
1289 either, which results in a memory region that will
1290 not be affected by reboots.
1292 *WARNING* If your board configuration uses automatic
1293 detection of the RAM size, you must make sure that
1294 this memory test is non-destructive. So far, the
1295 following board configurations are known to be
1298 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL,
1299 HERMES, IP860, RPXlite, LWMON, LANTEC,
1300 PCU_E, FLAGADM, TQM8260
1305 Define this variable to stop the system in case of a
1306 fatal error, so that you have to reset it manually.
1307 This is probably NOT a good idea for an embedded
1308 system where you want to system to reboot
1309 automatically as fast as possible, but it may be
1310 useful during development since you can try to debug
1311 the conditions that lead to the situation.
1313 CONFIG_NET_RETRY_COUNT
1315 This variable defines the number of retries for
1316 network operations like ARP, RARP, TFTP, or BOOTP
1317 before giving up the operation. If not defined, a
1318 default value of 5 is used.
1320 - Command Interpreter:
1323 Define this variable to enable the "hush" shell (from
1324 Busybox) as command line interpreter, thus enabling
1325 powerful command line syntax like
1326 if...then...else...fi conditionals or `&&' and '||'
1327 constructs ("shell scripts").
1329 If undefined, you get the old, much simpler behaviour
1330 with a somewhat smaller memory footprint.
1335 This defines the secondary prompt string, which is
1336 printed when the command interpreter needs more input
1337 to complete a command. Usually "> ".
1341 In the current implementation, the local variables
1342 space and global environment variables space are
1343 separated. Local variables are those you define by
1344 simply typing `name=value'. To access a local
1345 variable later on, you have write `$name' or
1346 `${name}'; to execute the contents of a variable
1347 directly type `$name' at the command prompt.
1349 Global environment variables are those you use
1350 setenv/printenv to work with. To run a command stored
1351 in such a variable, you need to use the run command,
1352 and you must not use the '$' sign to access them.
1354 To store commands and special characters in a
1355 variable, please use double quotation marks
1356 surrounding the whole text of the variable, instead
1357 of the backslashes before semicolons and special
1360 - Default Environment:
1361 CONFIG_EXTRA_ENV_SETTINGS
1363 Define this to contain any number of null terminated
1364 strings (variable = value pairs) that will be part of
1365 the default environment compiled into the boot image.
1367 For example, place something like this in your
1368 board's config file:
1370 #define CONFIG_EXTRA_ENV_SETTINGS \
1374 Warning: This method is based on knowledge about the
1375 internal format how the environment is stored by the
1376 U-Boot code. This is NOT an official, exported
1377 interface! Although it is unlikely that this format
1378 will change soon, there is no guarantee either.
1379 You better know what you are doing here.
1381 Note: overly (ab)use of the default environment is
1382 discouraged. Make sure to check other ways to preset
1383 the environment like the autoscript function or the
1386 - DataFlash Support:
1387 CONFIG_HAS_DATAFLASH
1389 Defining this option enables DataFlash features and
1390 allows to read/write in Dataflash via the standard
1393 - Show boot progress:
1394 CONFIG_SHOW_BOOT_PROGRESS
1396 Defining this option allows to add some board-
1397 specific code (calling a user-provided function
1398 "show_boot_progress(int)") that enables you to show
1399 the system's boot progress on some display (for
1400 example, some LED's) on your board. At the moment,
1401 the following checkpoints are implemented:
1404 1 common/cmd_bootm.c before attempting to boot an image
1405 -1 common/cmd_bootm.c Image header has bad magic number
1406 2 common/cmd_bootm.c Image header has correct magic number
1407 -2 common/cmd_bootm.c Image header has bad checksum
1408 3 common/cmd_bootm.c Image header has correct checksum
1409 -3 common/cmd_bootm.c Image data has bad checksum
1410 4 common/cmd_bootm.c Image data has correct checksum
1411 -4 common/cmd_bootm.c Image is for unsupported architecture
1412 5 common/cmd_bootm.c Architecture check OK
1413 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone)
1414 6 common/cmd_bootm.c Image Type check OK
1415 -6 common/cmd_bootm.c gunzip uncompression error
1416 -7 common/cmd_bootm.c Unimplemented compression type
1417 7 common/cmd_bootm.c Uncompression OK
1418 -8 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone)
1419 8 common/cmd_bootm.c Image Type check OK
1420 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
1421 9 common/cmd_bootm.c Start initial ramdisk verification
1422 -10 common/cmd_bootm.c Ramdisk header has bad magic number
1423 -11 common/cmd_bootm.c Ramdisk header has bad checksum
1424 10 common/cmd_bootm.c Ramdisk header is OK
1425 -12 common/cmd_bootm.c Ramdisk data has bad checksum
1426 11 common/cmd_bootm.c Ramdisk data has correct checksum
1427 12 common/cmd_bootm.c Ramdisk verification complete, start loading
1428 -13 common/cmd_bootm.c Wrong Image Type (not PPC Linux Ramdisk)
1429 13 common/cmd_bootm.c Start multifile image verification
1430 14 common/cmd_bootm.c No initial ramdisk, no multifile, continue.
1431 15 common/cmd_bootm.c All preparation done, transferring control to OS
1433 -1 common/cmd_doc.c Bad usage of "doc" command
1434 -1 common/cmd_doc.c No boot device
1435 -1 common/cmd_doc.c Unknown Chip ID on boot device
1436 -1 common/cmd_doc.c Read Error on boot device
1437 -1 common/cmd_doc.c Image header has bad magic number
1439 -1 common/cmd_ide.c Bad usage of "ide" command
1440 -1 common/cmd_ide.c No boot device
1441 -1 common/cmd_ide.c Unknown boot device
1442 -1 common/cmd_ide.c Unknown partition table
1443 -1 common/cmd_ide.c Invalid partition type
1444 -1 common/cmd_ide.c Read Error on boot device
1445 -1 common/cmd_ide.c Image header has bad magic number
1447 -1 common/cmd_nand.c Bad usage of "nand" command
1448 -1 common/cmd_nand.c No boot device
1449 -1 common/cmd_nand.c Unknown Chip ID on boot device
1450 -1 common/cmd_nand.c Read Error on boot device
1451 -1 common/cmd_nand.c Image header has bad magic number
1453 -1 common/env_common.c Environment has a bad CRC, using default
1459 [so far only for SMDK2400 and TRAB boards]
1461 - Modem support endable:
1462 CONFIG_MODEM_SUPPORT
1464 - RTS/CTS Flow control enable:
1467 - Modem debug support:
1468 CONFIG_MODEM_SUPPORT_DEBUG
1470 Enables debugging stuff (char screen[1024], dbg())
1471 for modem support. Useful only with BDI2000.
1473 - Interrupt support (PPC):
1475 There are common interrupt_init() and timer_interrupt()
1476 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
1477 for cpu specific initialization. interrupt_init_cpu()
1478 should set decrementer_count to appropriate value. If
1479 cpu resets decrementer automatically after interrupt
1480 (ppc4xx) it should set decrementer_count to zero.
1481 timer_interrupt() calls timer_interrupt_cpu() for cpu
1482 specific handling. If board has watchdog / status_led
1483 / other_activity_monitor it works automatically from
1484 general timer_interrupt().
1488 In the target system modem support is enabled when a
1489 specific key (key combination) is pressed during
1490 power-on. Otherwise U-Boot will boot normally
1491 (autoboot). The key_pressed() fuction is called from
1492 board_init(). Currently key_pressed() is a dummy
1493 function, returning 1 and thus enabling modem
1496 If there are no modem init strings in the
1497 environment, U-Boot proceed to autoboot; the
1498 previous output (banner, info printfs) will be
1501 See also: doc/README.Modem
1504 Configuration Settings:
1505 -----------------------
1507 - CFG_LONGHELP: Defined when you want long help messages included;
1508 undefine this when you're short of memory.
1510 - CFG_PROMPT: This is what U-Boot prints on the console to
1511 prompt for user input.
1513 - CFG_CBSIZE: Buffer size for input from the Console
1515 - CFG_PBSIZE: Buffer size for Console output
1517 - CFG_MAXARGS: max. Number of arguments accepted for monitor commands
1519 - CFG_BARGSIZE: Buffer size for Boot Arguments which are passed to
1520 the application (usually a Linux kernel) when it is
1523 - CFG_BAUDRATE_TABLE:
1524 List of legal baudrate settings for this board.
1526 - CFG_CONSOLE_INFO_QUIET
1527 Suppress display of console information at boot.
1529 - CFG_CONSOLE_IS_IN_ENV
1530 If the board specific function
1531 extern int overwrite_console (void);
1532 returns 1, the stdin, stderr and stdout are switched to the
1533 serial port, else the settings in the environment are used.
1535 - CFG_CONSOLE_OVERWRITE_ROUTINE
1536 Enable the call to overwrite_console().
1538 - CFG_CONSOLE_ENV_OVERWRITE
1539 Enable overwrite of previous console environment settings.
1541 - CFG_MEMTEST_START, CFG_MEMTEST_END:
1542 Begin and End addresses of the area used by the
1546 Enable an alternate, more extensive memory test.
1548 - CFG_MEMTEST_SCRATCH:
1549 Scratch address used by the alternate memory test
1550 You only need to set this if address zero isn't writeable
1552 - CFG_TFTP_LOADADDR:
1553 Default load address for network file downloads
1555 - CFG_LOADS_BAUD_CHANGE:
1556 Enable temporary baudrate change while serial download
1559 Physical start address of SDRAM. _Must_ be 0 here.
1562 Physical start address of Motherboard I/O (if using a
1566 Physical start address of Flash memory.
1569 Physical start address of boot monitor code (set by
1570 make config files to be same as the text base address
1571 (TEXT_BASE) used when linking) - same as
1572 CFG_FLASH_BASE when booting from flash.
1575 Size of memory reserved for monitor code, used to
1576 determine _at_compile_time_ (!) if the environment is
1577 embedded within the U-Boot image, or in a separate
1581 Size of DRAM reserved for malloc() use.
1584 Maximum size of memory mapped by the startup code of
1585 the Linux kernel; all data that must be processed by
1586 the Linux kernel (bd_info, boot arguments, eventually
1587 initrd image) must be put below this limit.
1589 - CFG_MAX_FLASH_BANKS:
1590 Max number of Flash memory banks
1592 - CFG_MAX_FLASH_SECT:
1593 Max number of sectors on a Flash chip
1595 - CFG_FLASH_ERASE_TOUT:
1596 Timeout for Flash erase operations (in ms)
1598 - CFG_FLASH_WRITE_TOUT:
1599 Timeout for Flash write operations (in ms)
1601 - CFG_FLASH_LOCK_TOUT
1602 Timeout for Flash set sector lock bit operation (in ms)
1604 - CFG_FLASH_UNLOCK_TOUT
1605 Timeout for Flash clear lock bits operation (in ms)
1607 - CFG_FLASH_PROTECTION
1608 If defined, hardware flash sectors protection is used
1609 instead of U-Boot software protection.
1611 - CFG_DIRECT_FLASH_TFTP:
1613 Enable TFTP transfers directly to flash memory;
1614 without this option such a download has to be
1615 performed in two steps: (1) download to RAM, and (2)
1616 copy from RAM to flash.
1618 The two-step approach is usually more reliable, since
1619 you can check if the download worked before you erase
1620 the flash, but in some situations (when sytem RAM is
1621 too limited to allow for a tempory copy of the
1622 downloaded image) this option may be very useful.
1625 Define if the flash driver uses extra elements in the
1626 common flash structure for storing flash geometry
1628 - CFG_RX_ETH_BUFFER:
1629 Defines the number of ethernet receive buffers. On some
1630 ethernet controllers it is recommended to set this value
1631 to 8 or even higher (EEPRO100 or 405 EMAC), since all
1632 buffers can be full shortly after enabling the interface
1633 on high ethernet traffic.
1634 Defaults to 4 if not defined.
1636 The following definitions that deal with the placement and management
1637 of environment data (variable area); in general, we support the
1638 following configurations:
1640 - CFG_ENV_IS_IN_FLASH:
1642 Define this if the environment is in flash memory.
1644 a) The environment occupies one whole flash sector, which is
1645 "embedded" in the text segment with the U-Boot code. This
1646 happens usually with "bottom boot sector" or "top boot
1647 sector" type flash chips, which have several smaller
1648 sectors at the start or the end. For instance, such a
1649 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
1650 such a case you would place the environment in one of the
1651 4 kB sectors - with U-Boot code before and after it. With
1652 "top boot sector" type flash chips, you would put the
1653 environment in one of the last sectors, leaving a gap
1654 between U-Boot and the environment.
1658 Offset of environment data (variable area) to the
1659 beginning of flash memory; for instance, with bottom boot
1660 type flash chips the second sector can be used: the offset
1661 for this sector is given here.
1663 CFG_ENV_OFFSET is used relative to CFG_FLASH_BASE.
1667 This is just another way to specify the start address of
1668 the flash sector containing the environment (instead of
1671 - CFG_ENV_SECT_SIZE:
1673 Size of the sector containing the environment.
1676 b) Sometimes flash chips have few, equal sized, BIG sectors.
1677 In such a case you don't want to spend a whole sector for
1682 If you use this in combination with CFG_ENV_IS_IN_FLASH
1683 and CFG_ENV_SECT_SIZE, you can specify to use only a part
1684 of this flash sector for the environment. This saves
1685 memory for the RAM copy of the environment.
1687 It may also save flash memory if you decide to use this
1688 when your environment is "embedded" within U-Boot code,
1689 since then the remainder of the flash sector could be used
1690 for U-Boot code. It should be pointed out that this is
1691 STRONGLY DISCOURAGED from a robustness point of view:
1692 updating the environment in flash makes it always
1693 necessary to erase the WHOLE sector. If something goes
1694 wrong before the contents has been restored from a copy in
1695 RAM, your target system will be dead.
1697 - CFG_ENV_ADDR_REDUND
1700 These settings describe a second storage area used to hold
1701 a redundand copy of the environment data, so that there is
1702 a valid backup copy in case there is a power failure during
1703 a "saveenv" operation.
1705 BE CAREFUL! Any changes to the flash layout, and some changes to the
1706 source code will make it necessary to adapt <board>/u-boot.lds*
1710 - CFG_ENV_IS_IN_NVRAM:
1712 Define this if you have some non-volatile memory device
1713 (NVRAM, battery buffered SRAM) which you want to use for the
1719 These two #defines are used to determin the memory area you
1720 want to use for environment. It is assumed that this memory
1721 can just be read and written to, without any special
1724 BE CAREFUL! The first access to the environment happens quite early
1725 in U-Boot initalization (when we try to get the setting of for the
1726 console baudrate). You *MUST* have mappend your NVRAM area then, or
1729 Please note that even with NVRAM we still use a copy of the
1730 environment in RAM: we could work on NVRAM directly, but we want to
1731 keep settings there always unmodified except somebody uses "saveenv"
1732 to save the current settings.
1735 - CFG_ENV_IS_IN_EEPROM:
1737 Use this if you have an EEPROM or similar serial access
1738 device and a driver for it.
1743 These two #defines specify the offset and size of the
1744 environment area within the total memory of your EEPROM.
1746 - CFG_I2C_EEPROM_ADDR:
1747 If defined, specified the chip address of the EEPROM device.
1748 The default address is zero.
1750 - CFG_EEPROM_PAGE_WRITE_BITS:
1751 If defined, the number of bits used to address bytes in a
1752 single page in the EEPROM device. A 64 byte page, for example
1753 would require six bits.
1755 - CFG_EEPROM_PAGE_WRITE_DELAY_MS:
1756 If defined, the number of milliseconds to delay between
1757 page writes. The default is zero milliseconds.
1759 - CFG_I2C_EEPROM_ADDR_LEN:
1760 The length in bytes of the EEPROM memory array address. Note
1761 that this is NOT the chip address length!
1764 The size in bytes of the EEPROM device.
1767 - CFG_ENV_IS_IN_DATAFLASH:
1769 Define this if you have a DataFlash memory device which you
1770 want to use for the environment.
1776 These three #defines specify the offset and size of the
1777 environment area within the total memory of your DataFlash placed
1778 at the specified address.
1781 - CFG_SPI_INIT_OFFSET
1783 Defines offset to the initial SPI buffer area in DPRAM. The
1784 area is used at an early stage (ROM part) if the environment
1785 is configured to reside in the SPI EEPROM: We need a 520 byte
1786 scratch DPRAM area. It is used between the two initialization
1787 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
1788 to be a good choice since it makes it far enough from the
1789 start of the data area as well as from the stack pointer.
1791 Please note that the environment is read-only as long as the monitor
1792 has been relocated to RAM and a RAM copy of the environment has been
1793 created; also, when using EEPROM you will have to use getenv_r()
1794 until then to read environment variables.
1796 The environment is protected by a CRC32 checksum. Before the monitor
1797 is relocated into RAM, as a result of a bad CRC you will be working
1798 with the compiled-in default environment - *silently*!!! [This is
1799 necessary, because the first environment variable we need is the
1800 "baudrate" setting for the console - if we have a bad CRC, we don't
1801 have any device yet where we could complain.]
1803 Note: once the monitor has been relocated, then it will complain if
1804 the default environment is used; a new CRC is computed as soon as you
1805 use the "saveenv" command to store a valid environment.
1807 - CFG_FAULT_ECHO_LINK_DOWN:
1808 Echo the inverted Ethernet link state to the fault LED.
1810 Note: If this option is active, then CFG_FAULT_MII_ADDR
1811 also needs to be defined.
1813 - CFG_FAULT_MII_ADDR:
1814 MII address of the PHY to check for the Ethernet link state.
1816 Low Level (hardware related) configuration options:
1817 ---------------------------------------------------
1819 - CFG_CACHELINE_SIZE:
1820 Cache Line Size of the CPU.
1823 Default address of the IMMR after system reset.
1825 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
1826 and RPXsuper) to be able to adjust the position of
1827 the IMMR register after a reset.
1829 - Floppy Disk Support:
1830 CFG_FDC_DRIVE_NUMBER
1832 the default drive number (default value 0)
1836 defines the spacing between fdc chipset registers
1841 defines the offset of register from address. It
1842 depends on which part of the data bus is connected to
1843 the fdc chipset. (default value 0)
1845 If CFG_ISA_IO_STRIDE CFG_ISA_IO_OFFSET and
1846 CFG_FDC_DRIVE_NUMBER are undefined, they take their
1849 if CFG_FDC_HW_INIT is defined, then the function
1850 fdc_hw_init() is called at the beginning of the FDC
1851 setup. fdc_hw_init() must be provided by the board
1852 source code. It is used to make hardware dependant
1855 - CFG_IMMR: Physical address of the Internal Memory Mapped
1856 Register; DO NOT CHANGE! (11-4)
1857 [MPC8xx systems only]
1859 - CFG_INIT_RAM_ADDR:
1861 Start address of memory area that can be used for
1862 initial data and stack; please note that this must be
1863 writable memory that is working WITHOUT special
1864 initialization, i. e. you CANNOT use normal RAM which
1865 will become available only after programming the
1866 memory controller and running certain initialization
1869 U-Boot uses the following memory types:
1870 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
1871 - MPC824X: data cache
1872 - PPC4xx: data cache
1874 - CFG_GBL_DATA_OFFSET:
1876 Offset of the initial data structure in the memory
1877 area defined by CFG_INIT_RAM_ADDR. Usually
1878 CFG_GBL_DATA_OFFSET is chosen such that the initial
1879 data is located at the end of the available space
1880 (sometimes written as (CFG_INIT_RAM_END -
1881 CFG_INIT_DATA_SIZE), and the initial stack is just
1882 below that area (growing from (CFG_INIT_RAM_ADDR +
1883 CFG_GBL_DATA_OFFSET) downward.
1886 On the MPC824X (or other systems that use the data
1887 cache for initial memory) the address chosen for
1888 CFG_INIT_RAM_ADDR is basically arbitrary - it must
1889 point to an otherwise UNUSED address space between
1890 the top of RAM and the start of the PCI space.
1892 - CFG_SIUMCR: SIU Module Configuration (11-6)
1894 - CFG_SYPCR: System Protection Control (11-9)
1896 - CFG_TBSCR: Time Base Status and Control (11-26)
1898 - CFG_PISCR: Periodic Interrupt Status and Control (11-31)
1900 - CFG_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
1902 - CFG_SCCR: System Clock and reset Control Register (15-27)
1904 - CFG_OR_TIMING_SDRAM:
1908 periodic timer for refresh
1910 - CFG_DER: Debug Event Register (37-47)
1912 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CFG_REMAP_OR_AM,
1913 CFG_PRELIM_OR_AM, CFG_OR_TIMING_FLASH, CFG_OR0_REMAP,
1914 CFG_OR0_PRELIM, CFG_BR0_PRELIM, CFG_OR1_REMAP, CFG_OR1_PRELIM,
1916 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
1918 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
1919 CFG_OR_TIMING_SDRAM, CFG_OR2_PRELIM, CFG_BR2_PRELIM,
1920 CFG_OR3_PRELIM, CFG_BR3_PRELIM:
1921 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
1923 - CFG_MAMR_PTA, CFG_MPTPR_2BK_4K, CFG_MPTPR_1BK_4K, CFG_MPTPR_2BK_8K,
1924 CFG_MPTPR_1BK_8K, CFG_MAMR_8COL, CFG_MAMR_9COL:
1925 Machine Mode Register and Memory Periodic Timer
1926 Prescaler definitions (SDRAM timing)
1928 - CFG_I2C_UCODE_PATCH, CFG_I2C_DPMEM_OFFSET [0x1FC0]:
1929 enable I2C microcode relocation patch (MPC8xx);
1930 define relocation offset in DPRAM [DSP2]
1932 - CFG_SPI_UCODE_PATCH, CFG_SPI_DPMEM_OFFSET [0x1FC0]:
1933 enable SPI microcode relocation patch (MPC8xx);
1934 define relocation offset in DPRAM [SCC4]
1937 Use OSCM clock mode on MBX8xx board. Be careful,
1938 wrong setting might damage your board. Read
1939 doc/README.MBX before setting this variable!
1941 - CFG_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
1942 Offset of the bootmode word in DPRAM used by post
1943 (Power On Self Tests). This definition overrides
1944 #define'd default value in commproc.h resp.
1947 - CFG_PCI_SLV_MEM_LOCAL, CFG_PCI_SLV_MEM_BUS, CFG_PICMR0_MASK_ATTRIB,
1948 CFG_PCI_MSTR0_LOCAL, CFG_PCIMSK0_MASK, CFG_PCI_MSTR1_LOCAL,
1949 CFG_PCIMSK1_MASK, CFG_PCI_MSTR_MEM_LOCAL, CFG_PCI_MSTR_MEM_BUS,
1950 CFG_CPU_PCI_MEM_START, CFG_PCI_MSTR_MEM_SIZE, CFG_POCMR0_MASK_ATTRIB,
1951 CFG_PCI_MSTR_MEMIO_LOCAL, CFG_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
1952 CFG_PCI_MSTR_MEMIO_SIZE, CFG_POCMR1_MASK_ATTRIB, CFG_PCI_MSTR_IO_LOCAL,
1953 CFG_PCI_MSTR_IO_BUS, CFG_CPU_PCI_IO_START, CFG_PCI_MSTR_IO_SIZE,
1954 CFG_POCMR2_MASK_ATTRIB: (MPC826x only)
1955 Overrides the default PCI memory map in cpu/mpc8260/pci.c if set.
1957 Building the Software:
1958 ======================
1960 Building U-Boot has been tested in native PPC environments (on a
1961 PowerBook G3 running LinuxPPC 2000) and in cross environments
1962 (running RedHat 6.x and 7.x Linux on x86, Solaris 2.6 on a SPARC, and
1965 If you are not using a native PPC environment, it is assumed that you
1966 have the GNU cross compiling tools available in your path and named
1967 with a prefix of "powerpc-linux-". If this is not the case, (e.g. if
1968 you are using Monta Vista's Hard Hat Linux CDK 1.2) you must change
1969 the definition of CROSS_COMPILE in Makefile. For HHL on a 4xx CPU,
1972 CROSS_COMPILE = ppc_4xx-
1975 U-Boot is intended to be simple to build. After installing the
1976 sources you must configure U-Boot for one specific board type. This
1981 where "NAME_config" is the name of one of the existing
1982 configurations; the following names are supported:
1984 ADCIOP_config GTH_config TQM850L_config
1985 ADS860_config IP860_config TQM855L_config
1986 AR405_config IVML24_config TQM860L_config
1987 CANBT_config IVMS8_config WALNUT405_config
1988 CPCI405_config LANTEC_config cogent_common_config
1989 CPCIISER4_config MBX_config cogent_mpc8260_config
1990 CU824_config MBX860T_config cogent_mpc8xx_config
1991 ESTEEM192E_config RPXlite_config hermes_config
1992 ETX094_config RPXsuper_config hymod_config
1993 FADS823_config SM850_config lwmon_config
1994 FADS850SAR_config SPD823TS_config pcu_e_config
1995 FADS860T_config SXNI855T_config rsdproto_config
1996 FPS850L_config Sandpoint8240_config sbc8260_config
1997 GENIETV_config TQM823L_config PIP405_config
1998 GEN860T_config EBONY_config FPS860L_config
1999 ELPT860_config cmi_mpc5xx_config NETVIA_config
2000 at91rm9200dk_config omap1510inn_config MPC8260ADS_config
2001 omap1610inn_config ZPC1900_config MPC8540ADS_config
2002 MPC8560ADS_config QS850_config QS823_config
2005 Note: for some board special configuration names may exist; check if
2006 additional information is available from the board vendor; for
2007 instance, the TQM8xxL systems run normally at 50 MHz and use a
2008 SCC for 10baseT ethernet; there are also systems with 80 MHz
2009 CPU clock, and an optional Fast Ethernet module is available
2010 for CPU's with FEC. You can select such additional "features"
2011 when chosing the configuration, i. e.
2014 - will configure for a plain TQM860L, i. e. 50MHz, no FEC
2016 make TQM860L_FEC_config
2017 - will configure for a TQM860L at 50MHz with FEC for ethernet
2019 make TQM860L_80MHz_config
2020 - will configure for a TQM860L at 80 MHz, with normal 10baseT
2023 make TQM860L_FEC_80MHz_config
2024 - will configure for a TQM860L at 80 MHz with FEC for ethernet
2026 make TQM823L_LCD_config
2027 - will configure for a TQM823L with U-Boot console on LCD
2029 make TQM823L_LCD_80MHz_config
2030 - will configure for a TQM823L at 80 MHz with U-Boot console on LCD
2035 Finally, type "make all", and you should get some working U-Boot
2036 images ready for download to / installation on your system:
2038 - "u-boot.bin" is a raw binary image
2039 - "u-boot" is an image in ELF binary format
2040 - "u-boot.srec" is in Motorola S-Record format
2043 Please be aware that the Makefiles assume you are using GNU make, so
2044 for instance on NetBSD you might need to use "gmake" instead of
2048 If the system board that you have is not listed, then you will need
2049 to port U-Boot to your hardware platform. To do this, follow these
2052 1. Add a new configuration option for your board to the toplevel
2053 "Makefile" and to the "MAKEALL" script, using the existing
2054 entries as examples. Note that here and at many other places
2055 boards and other names are listed in alphabetical sort order. Please
2057 2. Create a new directory to hold your board specific code. Add any
2058 files you need. In your board directory, you will need at least
2059 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
2060 3. Create a new configuration file "include/configs/<board>.h" for
2062 3. If you're porting U-Boot to a new CPU, then also create a new
2063 directory to hold your CPU specific code. Add any files you need.
2064 4. Run "make <board>_config" with your new name.
2065 5. Type "make", and you should get a working "u-boot.srec" file
2066 to be installed on your target system.
2067 6. Debug and solve any problems that might arise.
2068 [Of course, this last step is much harder than it sounds.]
2071 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
2072 ==============================================================
2074 If you have modified U-Boot sources (for instance added a new board
2075 or support for new devices, a new CPU, etc.) you are expected to
2076 provide feedback to the other developers. The feedback normally takes
2077 the form of a "patch", i. e. a context diff against a certain (latest
2078 official or latest in CVS) version of U-Boot sources.
2080 But before you submit such a patch, please verify that your modifi-
2081 cation did not break existing code. At least make sure that *ALL* of
2082 the supported boards compile WITHOUT ANY compiler warnings. To do so,
2083 just run the "MAKEALL" script, which will configure and build U-Boot
2084 for ALL supported system. Be warned, this will take a while. You can
2085 select which (cross) compiler to use by passing a `CROSS_COMPILE'
2086 environment variable to the script, i. e. to use the cross tools from
2087 MontaVista's Hard Hat Linux you can type
2089 CROSS_COMPILE=ppc_8xx- MAKEALL
2091 or to build on a native PowerPC system you can type
2093 CROSS_COMPILE=' ' MAKEALL
2095 See also "U-Boot Porting Guide" below.
2098 Monitor Commands - Overview:
2099 ============================
2101 go - start application at address 'addr'
2102 run - run commands in an environment variable
2103 bootm - boot application image from memory
2104 bootp - boot image via network using BootP/TFTP protocol
2105 tftpboot- boot image via network using TFTP protocol
2106 and env variables "ipaddr" and "serverip"
2107 (and eventually "gatewayip")
2108 rarpboot- boot image via network using RARP/TFTP protocol
2109 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
2110 loads - load S-Record file over serial line
2111 loadb - load binary file over serial line (kermit mode)
2113 mm - memory modify (auto-incrementing)
2114 nm - memory modify (constant address)
2115 mw - memory write (fill)
2117 cmp - memory compare
2118 crc32 - checksum calculation
2119 imd - i2c memory display
2120 imm - i2c memory modify (auto-incrementing)
2121 inm - i2c memory modify (constant address)
2122 imw - i2c memory write (fill)
2123 icrc32 - i2c checksum calculation
2124 iprobe - probe to discover valid I2C chip addresses
2125 iloop - infinite loop on address range
2126 isdram - print SDRAM configuration information
2127 sspi - SPI utility commands
2128 base - print or set address offset
2129 printenv- print environment variables
2130 setenv - set environment variables
2131 saveenv - save environment variables to persistent storage
2132 protect - enable or disable FLASH write protection
2133 erase - erase FLASH memory
2134 flinfo - print FLASH memory information
2135 bdinfo - print Board Info structure
2136 iminfo - print header information for application image
2137 coninfo - print console devices and informations
2138 ide - IDE sub-system
2139 loop - infinite loop on address range
2140 mtest - simple RAM test
2141 icache - enable or disable instruction cache
2142 dcache - enable or disable data cache
2143 reset - Perform RESET of the CPU
2144 echo - echo args to console
2145 version - print monitor version
2146 help - print online help
2147 ? - alias for 'help'
2150 Monitor Commands - Detailed Description:
2151 ========================================
2155 For now: just type "help <command>".
2158 Environment Variables:
2159 ======================
2161 U-Boot supports user configuration using Environment Variables which
2162 can be made persistent by saving to Flash memory.
2164 Environment Variables are set using "setenv", printed using
2165 "printenv", and saved to Flash using "saveenv". Using "setenv"
2166 without a value can be used to delete a variable from the
2167 environment. As long as you don't save the environment you are
2168 working with an in-memory copy. In case the Flash area containing the
2169 environment is erased by accident, a default environment is provided.
2171 Some configuration options can be set using Environment Variables:
2173 baudrate - see CONFIG_BAUDRATE
2175 bootdelay - see CONFIG_BOOTDELAY
2177 bootcmd - see CONFIG_BOOTCOMMAND
2179 bootargs - Boot arguments when booting an RTOS image
2181 bootfile - Name of the image to load with TFTP
2183 autoload - if set to "no" (any string beginning with 'n'),
2184 "bootp" will just load perform a lookup of the
2185 configuration from the BOOTP server, but not try to
2186 load any image using TFTP
2188 autostart - if set to "yes", an image loaded using the "bootp",
2189 "rarpboot", "tftpboot" or "diskboot" commands will
2190 be automatically started (by internally calling
2193 If set to "no", a standalone image passed to the
2194 "bootm" command will be copied to the load address
2195 (and eventually uncompressed), but NOT be started.
2196 This can be used to load and uncompress arbitrary
2199 initrd_high - restrict positioning of initrd images:
2200 If this variable is not set, initrd images will be
2201 copied to the highest possible address in RAM; this
2202 is usually what you want since it allows for
2203 maximum initrd size. If for some reason you want to
2204 make sure that the initrd image is loaded below the
2205 CFG_BOOTMAPSZ limit, you can set this environment
2206 variable to a value of "no" or "off" or "0".
2207 Alternatively, you can set it to a maximum upper
2208 address to use (U-Boot will still check that it
2209 does not overwrite the U-Boot stack and data).
2211 For instance, when you have a system with 16 MB
2212 RAM, and want to reserve 4 MB from use by Linux,
2213 you can do this by adding "mem=12M" to the value of
2214 the "bootargs" variable. However, now you must make
2215 sure that the initrd image is placed in the first
2216 12 MB as well - this can be done with
2218 setenv initrd_high 00c00000
2220 If you set initrd_high to 0xFFFFFFFF, this is an
2221 indication to U-Boot that all addresses are legal
2222 for the Linux kernel, including addresses in flash
2223 memory. In this case U-Boot will NOT COPY the
2224 ramdisk at all. This may be useful to reduce the
2225 boot time on your system, but requires that this
2226 feature is supported by your Linux kernel.
2228 ipaddr - IP address; needed for tftpboot command
2230 loadaddr - Default load address for commands like "bootp",
2231 "rarpboot", "tftpboot", "loadb" or "diskboot"
2233 loads_echo - see CONFIG_LOADS_ECHO
2235 serverip - TFTP server IP address; needed for tftpboot command
2237 bootretry - see CONFIG_BOOT_RETRY_TIME
2239 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
2241 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
2244 The following environment variables may be used and automatically
2245 updated by the network boot commands ("bootp" and "rarpboot"),
2246 depending the information provided by your boot server:
2248 bootfile - see above
2249 dnsip - IP address of your Domain Name Server
2250 dnsip2 - IP address of your secondary Domain Name Server
2251 gatewayip - IP address of the Gateway (Router) to use
2252 hostname - Target hostname
2254 netmask - Subnet Mask
2255 rootpath - Pathname of the root filesystem on the NFS server
2256 serverip - see above
2259 There are two special Environment Variables:
2261 serial# - contains hardware identification information such
2262 as type string and/or serial number
2263 ethaddr - Ethernet address
2265 These variables can be set only once (usually during manufacturing of
2266 the board). U-Boot refuses to delete or overwrite these variables
2267 once they have been set once.
2270 Further special Environment Variables:
2272 ver - Contains the U-Boot version string as printed
2273 with the "version" command. This variable is
2274 readonly (see CONFIG_VERSION_VARIABLE).
2277 Please note that changes to some configuration parameters may take
2278 only effect after the next boot (yes, that's just like Windoze :-).
2281 Command Line Parsing:
2282 =====================
2284 There are two different command line parsers available with U-Boot:
2285 the old "simple" one, and the much more powerful "hush" shell:
2287 Old, simple command line parser:
2288 --------------------------------
2290 - supports environment variables (through setenv / saveenv commands)
2291 - several commands on one line, separated by ';'
2292 - variable substitution using "... $(name) ..." syntax
2293 - special characters ('$', ';') can be escaped by prefixing with '\',
2295 setenv bootcmd bootm \$(address)
2296 - You can also escape text by enclosing in single apostrophes, for example:
2297 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
2302 - similar to Bourne shell, with control structures like
2303 if...then...else...fi, for...do...done; while...do...done,
2304 until...do...done, ...
2305 - supports environment ("global") variables (through setenv / saveenv
2306 commands) and local shell variables (through standard shell syntax
2307 "name=value"); only environment variables can be used with "run"
2313 (1) If a command line (or an environment variable executed by a "run"
2314 command) contains several commands separated by semicolon, and
2315 one of these commands fails, then the remaining commands will be
2318 (2) If you execute several variables with one call to run (i. e.
2319 calling run with a list af variables as arguments), any failing
2320 command will cause "run" to terminate, i. e. the remaining
2321 variables are not executed.
2323 Note for Redundant Ethernet Interfaces:
2324 =======================================
2326 Some boards come with redundant ethernet interfaces; U-Boot supports
2327 such configurations and is capable of automatic selection of a
2328 "working" interface when needed. MAC assignment works as follows:
2330 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
2331 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
2332 "eth1addr" (=>eth1), "eth2addr", ...
2334 If the network interface stores some valid MAC address (for instance
2335 in SROM), this is used as default address if there is NO correspon-
2336 ding setting in the environment; if the corresponding environment
2337 variable is set, this overrides the settings in the card; that means:
2339 o If the SROM has a valid MAC address, and there is no address in the
2340 environment, the SROM's address is used.
2342 o If there is no valid address in the SROM, and a definition in the
2343 environment exists, then the value from the environment variable is
2346 o If both the SROM and the environment contain a MAC address, and
2347 both addresses are the same, this MAC address is used.
2349 o If both the SROM and the environment contain a MAC address, and the
2350 addresses differ, the value from the environment is used and a
2353 o If neither SROM nor the environment contain a MAC address, an error
2360 The "boot" commands of this monitor operate on "image" files which
2361 can be basicly anything, preceeded by a special header; see the
2362 definitions in include/image.h for details; basicly, the header
2363 defines the following image properties:
2365 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
2366 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
2367 LynxOS, pSOS, QNX, RTEMS, ARTOS;
2368 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, ARTOS, LynxOS).
2369 * Target CPU Architecture (Provisions for Alpha, ARM, Intel x86,
2370 IA64, MIPS, NIOS, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
2371 Currently supported: ARM, Intel x86, MIPS, NIOS, PowerPC).
2372 * Compression Type (uncompressed, gzip, bzip2)
2378 The header is marked by a special Magic Number, and both the header
2379 and the data portions of the image are secured against corruption by
2386 Although U-Boot should support any OS or standalone application
2387 easily, the main focus has always been on Linux during the design of
2390 U-Boot includes many features that so far have been part of some
2391 special "boot loader" code within the Linux kernel. Also, any
2392 "initrd" images to be used are no longer part of one big Linux image;
2393 instead, kernel and "initrd" are separate images. This implementation
2394 serves several purposes:
2396 - the same features can be used for other OS or standalone
2397 applications (for instance: using compressed images to reduce the
2398 Flash memory footprint)
2400 - it becomes much easier to port new Linux kernel versions because
2401 lots of low-level, hardware dependent stuff are done by U-Boot
2403 - the same Linux kernel image can now be used with different "initrd"
2404 images; of course this also means that different kernel images can
2405 be run with the same "initrd". This makes testing easier (you don't
2406 have to build a new "zImage.initrd" Linux image when you just
2407 change a file in your "initrd"). Also, a field-upgrade of the
2408 software is easier now.
2414 Porting Linux to U-Boot based systems:
2415 ---------------------------------------
2417 U-Boot cannot save you from doing all the necessary modifications to
2418 configure the Linux device drivers for use with your target hardware
2419 (no, we don't intend to provide a full virtual machine interface to
2422 But now you can ignore ALL boot loader code (in arch/ppc/mbxboot).
2424 Just make sure your machine specific header file (for instance
2425 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
2426 Information structure as we define in include/u-boot.h, and make
2427 sure that your definition of IMAP_ADDR uses the same value as your
2428 U-Boot configuration in CFG_IMMR.
2431 Configuring the Linux kernel:
2432 -----------------------------
2434 No specific requirements for U-Boot. Make sure you have some root
2435 device (initial ramdisk, NFS) for your target system.
2438 Building a Linux Image:
2439 -----------------------
2441 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
2442 not used. If you use recent kernel source, a new build target
2443 "uImage" will exist which automatically builds an image usable by
2444 U-Boot. Most older kernels also have support for a "pImage" target,
2445 which was introduced for our predecessor project PPCBoot and uses a
2446 100% compatible format.
2455 The "uImage" build target uses a special tool (in 'tools/mkimage') to
2456 encapsulate a compressed Linux kernel image with header information,
2457 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
2459 * build a standard "vmlinux" kernel image (in ELF binary format):
2461 * convert the kernel into a raw binary image:
2463 ${CROSS_COMPILE}-objcopy -O binary \
2464 -R .note -R .comment \
2465 -S vmlinux linux.bin
2467 * compress the binary image:
2471 * package compressed binary image for U-Boot:
2473 mkimage -A ppc -O linux -T kernel -C gzip \
2474 -a 0 -e 0 -n "Linux Kernel Image" \
2475 -d linux.bin.gz uImage
2478 The "mkimage" tool can also be used to create ramdisk images for use
2479 with U-Boot, either separated from the Linux kernel image, or
2480 combined into one file. "mkimage" encapsulates the images with a 64
2481 byte header containing information about target architecture,
2482 operating system, image type, compression method, entry points, time
2483 stamp, CRC32 checksums, etc.
2485 "mkimage" can be called in two ways: to verify existing images and
2486 print the header information, or to build new images.
2488 In the first form (with "-l" option) mkimage lists the information
2489 contained in the header of an existing U-Boot image; this includes
2490 checksum verification:
2492 tools/mkimage -l image
2493 -l ==> list image header information
2495 The second form (with "-d" option) is used to build a U-Boot image
2496 from a "data file" which is used as image payload:
2498 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
2499 -n name -d data_file image
2500 -A ==> set architecture to 'arch'
2501 -O ==> set operating system to 'os'
2502 -T ==> set image type to 'type'
2503 -C ==> set compression type 'comp'
2504 -a ==> set load address to 'addr' (hex)
2505 -e ==> set entry point to 'ep' (hex)
2506 -n ==> set image name to 'name'
2507 -d ==> use image data from 'datafile'
2509 Right now, all Linux kernels use the same load address (0x00000000),
2510 but the entry point address depends on the kernel version:
2512 - 2.2.x kernels have the entry point at 0x0000000C,
2513 - 2.3.x and later kernels have the entry point at 0x00000000.
2515 So a typical call to build a U-Boot image would read:
2517 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
2518 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
2519 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz \
2520 > 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 To verify the contents of the image (or check for corruption):
2530 -> tools/mkimage -l examples/uImage.TQM850L
2531 Image Name: 2.4.4 kernel for TQM850L
2532 Created: Wed Jul 19 02:34:59 2000
2533 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2534 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
2535 Load Address: 0x00000000
2536 Entry Point: 0x00000000
2538 NOTE: for embedded systems where boot time is critical you can trade
2539 speed for memory and install an UNCOMPRESSED image instead: this
2540 needs more space in Flash, but boots much faster since it does not
2541 need to be uncompressed:
2543 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz
2544 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
2545 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
2546 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux \
2547 > examples/uImage.TQM850L-uncompressed
2548 Image Name: 2.4.4 kernel for TQM850L
2549 Created: Wed Jul 19 02:34:59 2000
2550 Image Type: PowerPC Linux Kernel Image (uncompressed)
2551 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
2552 Load Address: 0x00000000
2553 Entry Point: 0x00000000
2556 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
2557 when your kernel is intended to use an initial ramdisk:
2559 -> tools/mkimage -n 'Simple Ramdisk Image' \
2560 > -A ppc -O linux -T ramdisk -C gzip \
2561 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
2562 Image Name: Simple Ramdisk Image
2563 Created: Wed Jan 12 14:01:50 2000
2564 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2565 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
2566 Load Address: 0x00000000
2567 Entry Point: 0x00000000
2570 Installing a Linux Image:
2571 -------------------------
2573 To downloading a U-Boot image over the serial (console) interface,
2574 you must convert the image to S-Record format:
2576 objcopy -I binary -O srec examples/image examples/image.srec
2578 The 'objcopy' does not understand the information in the U-Boot
2579 image header, so the resulting S-Record file will be relative to
2580 address 0x00000000. To load it to a given address, you need to
2581 specify the target address as 'offset' parameter with the 'loads'
2584 Example: install the image to address 0x40100000 (which on the
2585 TQM8xxL is in the first Flash bank):
2587 => erase 40100000 401FFFFF
2593 ## Ready for S-Record download ...
2594 ~>examples/image.srec
2595 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
2597 15989 15990 15991 15992
2598 [file transfer complete]
2600 ## Start Addr = 0x00000000
2603 You can check the success of the download using the 'iminfo' command;
2604 this includes a checksum verification so you can be sure no data
2605 corruption happened:
2609 ## Checking Image at 40100000 ...
2610 Image Name: 2.2.13 for initrd on TQM850L
2611 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2612 Data Size: 335725 Bytes = 327 kB = 0 MB
2613 Load Address: 00000000
2614 Entry Point: 0000000c
2615 Verifying Checksum ... OK
2621 The "bootm" command is used to boot an application that is stored in
2622 memory (RAM or Flash). In case of a Linux kernel image, the contents
2623 of the "bootargs" environment variable is passed to the kernel as
2624 parameters. You can check and modify this variable using the
2625 "printenv" and "setenv" commands:
2628 => printenv bootargs
2629 bootargs=root=/dev/ram
2631 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2633 => printenv bootargs
2634 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2637 ## Booting Linux kernel at 40020000 ...
2638 Image Name: 2.2.13 for NFS on TQM850L
2639 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2640 Data Size: 381681 Bytes = 372 kB = 0 MB
2641 Load Address: 00000000
2642 Entry Point: 0000000c
2643 Verifying Checksum ... OK
2644 Uncompressing Kernel Image ... OK
2645 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
2646 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2647 time_init: decrementer frequency = 187500000/60
2648 Calibrating delay loop... 49.77 BogoMIPS
2649 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
2652 If you want to boot a Linux kernel with initial ram disk, you pass
2653 the memory addresses of both the kernel and the initrd image (PPBCOOT
2654 format!) to the "bootm" command:
2656 => imi 40100000 40200000
2658 ## Checking Image at 40100000 ...
2659 Image Name: 2.2.13 for initrd on TQM850L
2660 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2661 Data Size: 335725 Bytes = 327 kB = 0 MB
2662 Load Address: 00000000
2663 Entry Point: 0000000c
2664 Verifying Checksum ... OK
2666 ## Checking Image at 40200000 ...
2667 Image Name: Simple Ramdisk Image
2668 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2669 Data Size: 566530 Bytes = 553 kB = 0 MB
2670 Load Address: 00000000
2671 Entry Point: 00000000
2672 Verifying Checksum ... OK
2674 => bootm 40100000 40200000
2675 ## Booting Linux kernel at 40100000 ...
2676 Image Name: 2.2.13 for initrd on TQM850L
2677 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2678 Data Size: 335725 Bytes = 327 kB = 0 MB
2679 Load Address: 00000000
2680 Entry Point: 0000000c
2681 Verifying Checksum ... OK
2682 Uncompressing Kernel Image ... OK
2683 ## Loading RAMDisk Image at 40200000 ...
2684 Image Name: Simple Ramdisk Image
2685 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2686 Data Size: 566530 Bytes = 553 kB = 0 MB
2687 Load Address: 00000000
2688 Entry Point: 00000000
2689 Verifying Checksum ... OK
2690 Loading Ramdisk ... OK
2691 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
2692 Boot arguments: root=/dev/ram
2693 time_init: decrementer frequency = 187500000/60
2694 Calibrating delay loop... 49.77 BogoMIPS
2696 RAMDISK: Compressed image found at block 0
2697 VFS: Mounted root (ext2 filesystem).
2701 More About U-Boot Image Types:
2702 ------------------------------
2704 U-Boot supports the following image types:
2706 "Standalone Programs" are directly runnable in the environment
2707 provided by U-Boot; it is expected that (if they behave
2708 well) you can continue to work in U-Boot after return from
2709 the Standalone Program.
2710 "OS Kernel Images" are usually images of some Embedded OS which
2711 will take over control completely. Usually these programs
2712 will install their own set of exception handlers, device
2713 drivers, set up the MMU, etc. - this means, that you cannot
2714 expect to re-enter U-Boot except by resetting the CPU.
2715 "RAMDisk Images" are more or less just data blocks, and their
2716 parameters (address, size) are passed to an OS kernel that is
2718 "Multi-File Images" contain several images, typically an OS
2719 (Linux) kernel image and one or more data images like
2720 RAMDisks. This construct is useful for instance when you want
2721 to boot over the network using BOOTP etc., where the boot
2722 server provides just a single image file, but you want to get
2723 for instance an OS kernel and a RAMDisk image.
2725 "Multi-File Images" start with a list of image sizes, each
2726 image size (in bytes) specified by an "uint32_t" in network
2727 byte order. This list is terminated by an "(uint32_t)0".
2728 Immediately after the terminating 0 follow the images, one by
2729 one, all aligned on "uint32_t" boundaries (size rounded up to
2730 a multiple of 4 bytes).
2732 "Firmware Images" are binary images containing firmware (like
2733 U-Boot or FPGA images) which usually will be programmed to
2736 "Script files" are command sequences that will be executed by
2737 U-Boot's command interpreter; this feature is especially
2738 useful when you configure U-Boot to use a real shell (hush)
2739 as command interpreter.
2745 One of the features of U-Boot is that you can dynamically load and
2746 run "standalone" applications, which can use some resources of
2747 U-Boot like console I/O functions or interrupt services.
2749 Two simple examples are included with the sources:
2754 'examples/hello_world.c' contains a small "Hello World" Demo
2755 application; it is automatically compiled when you build U-Boot.
2756 It's configured to run at address 0x00040004, so you can play with it
2760 ## Ready for S-Record download ...
2761 ~>examples/hello_world.srec
2762 1 2 3 4 5 6 7 8 9 10 11 ...
2763 [file transfer complete]
2765 ## Start Addr = 0x00040004
2767 => go 40004 Hello World! This is a test.
2768 ## Starting application at 0x00040004 ...
2779 Hit any key to exit ...
2781 ## Application terminated, rc = 0x0
2783 Another example, which demonstrates how to register a CPM interrupt
2784 handler with the U-Boot code, can be found in 'examples/timer.c'.
2785 Here, a CPM timer is set up to generate an interrupt every second.
2786 The interrupt service routine is trivial, just printing a '.'
2787 character, but this is just a demo program. The application can be
2788 controlled by the following keys:
2790 ? - print current values og the CPM Timer registers
2791 b - enable interrupts and start timer
2792 e - stop timer and disable interrupts
2793 q - quit application
2796 ## Ready for S-Record download ...
2797 ~>examples/timer.srec
2798 1 2 3 4 5 6 7 8 9 10 11 ...
2799 [file transfer complete]
2801 ## Start Addr = 0x00040004
2804 ## Starting application at 0x00040004 ...
2807 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
2810 [q, b, e, ?] Set interval 1000000 us
2813 [q, b, e, ?] ........
2814 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
2817 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
2820 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
2823 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
2825 [q, b, e, ?] ...Stopping timer
2827 [q, b, e, ?] ## Application terminated, rc = 0x0
2833 Over time, many people have reported problems when trying to use the
2834 "minicom" terminal emulation program for serial download. I (wd)
2835 consider minicom to be broken, and recommend not to use it. Under
2836 Unix, I recommend to use C-Kermit for general purpose use (and
2837 especially for kermit binary protocol download ("loadb" command), and
2838 use "cu" for S-Record download ("loads" command).
2840 Nevertheless, if you absolutely want to use it try adding this
2841 configuration to your "File transfer protocols" section:
2843 Name Program Name U/D FullScr IO-Red. Multi
2844 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
2845 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
2851 Starting at version 0.9.2, U-Boot supports NetBSD both as host
2852 (build U-Boot) and target system (boots NetBSD/mpc8xx).
2854 Building requires a cross environment; it is known to work on
2855 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
2856 need gmake since the Makefiles are not compatible with BSD make).
2857 Note that the cross-powerpc package does not install include files;
2858 attempting to build U-Boot will fail because <machine/ansi.h> is
2859 missing. This file has to be installed and patched manually:
2861 # cd /usr/pkg/cross/powerpc-netbsd/include
2863 # ln -s powerpc machine
2864 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
2865 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
2867 Native builds *don't* work due to incompatibilities between native
2868 and U-Boot include files.
2870 Booting assumes that (the first part of) the image booted is a
2871 stage-2 loader which in turn loads and then invokes the kernel
2872 proper. Loader sources will eventually appear in the NetBSD source
2873 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
2874 meantime, send mail to bruno@exet-ag.de and/or wd@denx.de for
2878 Implementation Internals:
2879 =========================
2881 The following is not intended to be a complete description of every
2882 implementation detail. However, it should help to understand the
2883 inner workings of U-Boot and make it easier to port it to custom
2887 Initial Stack, Global Data:
2888 ---------------------------
2890 The implementation of U-Boot is complicated by the fact that U-Boot
2891 starts running out of ROM (flash memory), usually without access to
2892 system RAM (because the memory controller is not initialized yet).
2893 This means that we don't have writable Data or BSS segments, and BSS
2894 is not initialized as zero. To be able to get a C environment working
2895 at all, we have to allocate at least a minimal stack. Implementation
2896 options for this are defined and restricted by the CPU used: Some CPU
2897 models provide on-chip memory (like the IMMR area on MPC8xx and
2898 MPC826x processors), on others (parts of) the data cache can be
2899 locked as (mis-) used as memory, etc.
2901 Chris Hallinan posted a good summary of these issues to the
2902 u-boot-users mailing list:
2904 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
2905 From: "Chris Hallinan" <clh@net1plus.com>
2906 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
2909 Correct me if I'm wrong, folks, but the way I understand it
2910 is this: Using DCACHE as initial RAM for Stack, etc, does not
2911 require any physical RAM backing up the cache. The cleverness
2912 is that the cache is being used as a temporary supply of
2913 necessary storage before the SDRAM controller is setup. It's
2914 beyond the scope of this list to expain the details, but you
2915 can see how this works by studying the cache architecture and
2916 operation in the architecture and processor-specific manuals.
2918 OCM is On Chip Memory, which I believe the 405GP has 4K. It
2919 is another option for the system designer to use as an
2920 initial stack/ram area prior to SDRAM being available. Either
2921 option should work for you. Using CS 4 should be fine if your
2922 board designers haven't used it for something that would
2923 cause you grief during the initial boot! It is frequently not
2926 CFG_INIT_RAM_ADDR should be somewhere that won't interfere
2927 with your processor/board/system design. The default value
2928 you will find in any recent u-boot distribution in
2929 Walnut405.h should work for you. I'd set it to a value larger
2930 than your SDRAM module. If you have a 64MB SDRAM module, set
2931 it above 400_0000. Just make sure your board has no resources
2932 that are supposed to respond to that address! That code in
2933 start.S has been around a while and should work as is when
2934 you get the config right.
2939 It is essential to remember this, since it has some impact on the C
2940 code for the initialization procedures:
2942 * Initialized global data (data segment) is read-only. Do not attempt
2945 * Do not use any unitialized global data (or implicitely initialized
2946 as zero data - BSS segment) at all - this is undefined, initiali-
2947 zation is performed later (when relocating to RAM).
2949 * Stack space is very limited. Avoid big data buffers or things like
2952 Having only the stack as writable memory limits means we cannot use
2953 normal global data to share information beween the code. But it
2954 turned out that the implementation of U-Boot can be greatly
2955 simplified by making a global data structure (gd_t) available to all
2956 functions. We could pass a pointer to this data as argument to _all_
2957 functions, but this would bloat the code. Instead we use a feature of
2958 the GCC compiler (Global Register Variables) to share the data: we
2959 place a pointer (gd) to the global data into a register which we
2960 reserve for this purpose.
2962 When choosing a register for such a purpose we are restricted by the
2963 relevant (E)ABI specifications for the current architecture, and by
2964 GCC's implementation.
2966 For PowerPC, the following registers have specific use:
2969 R3-R4: parameter passing and return values
2970 R5-R10: parameter passing
2971 R13: small data area pointer
2975 (U-Boot also uses R14 as internal GOT pointer.)
2977 ==> U-Boot will use R29 to hold a pointer to the global data
2979 Note: on PPC, we could use a static initializer (since the
2980 address of the global data structure is known at compile time),
2981 but it turned out that reserving a register results in somewhat
2982 smaller code - although the code savings are not that big (on
2983 average for all boards 752 bytes for the whole U-Boot image,
2984 624 text + 127 data).
2986 On ARM, the following registers are used:
2988 R0: function argument word/integer result
2989 R1-R3: function argument word
2991 R10: stack limit (used only if stack checking if enabled)
2992 R11: argument (frame) pointer
2993 R12: temporary workspace
2996 R15: program counter
2998 ==> U-Boot will use R8 to hold a pointer to the global data
3004 U-Boot runs in system state and uses physical addresses, i.e. the
3005 MMU is not used either for address mapping nor for memory protection.
3007 The available memory is mapped to fixed addresses using the memory
3008 controller. In this process, a contiguous block is formed for each
3009 memory type (Flash, SDRAM, SRAM), even when it consists of several
3010 physical memory banks.
3012 U-Boot is installed in the first 128 kB of the first Flash bank (on
3013 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
3014 booting and sizing and initializing DRAM, the code relocates itself
3015 to the upper end of DRAM. Immediately below the U-Boot code some
3016 memory is reserved for use by malloc() [see CFG_MALLOC_LEN
3017 configuration setting]. Below that, a structure with global Board
3018 Info data is placed, followed by the stack (growing downward).
3020 Additionally, some exception handler code is copied to the low 8 kB
3021 of DRAM (0x00000000 ... 0x00001FFF).
3023 So a typical memory configuration with 16 MB of DRAM could look like
3026 0x0000 0000 Exception Vector code
3029 0x0000 2000 Free for Application Use
3035 0x00FB FF20 Monitor Stack (Growing downward)
3036 0x00FB FFAC Board Info Data and permanent copy of global data
3037 0x00FC 0000 Malloc Arena
3040 0x00FE 0000 RAM Copy of Monitor Code
3041 ... eventually: LCD or video framebuffer
3042 ... eventually: pRAM (Protected RAM - unchanged by reset)
3043 0x00FF FFFF [End of RAM]
3046 System Initialization:
3047 ----------------------
3049 In the reset configuration, U-Boot starts at the reset entry point
3050 (on most PowerPC systens at address 0x00000100). Because of the reset
3051 configuration for CS0# this is a mirror of the onboard Flash memory.
3052 To be able to re-map memory U-Boot then jumps to its link address.
3053 To be able to implement the initialization code in C, a (small!)
3054 initial stack is set up in the internal Dual Ported RAM (in case CPUs
3055 which provide such a feature like MPC8xx or MPC8260), or in a locked
3056 part of the data cache. After that, U-Boot initializes the CPU core,
3057 the caches and the SIU.
3059 Next, all (potentially) available memory banks are mapped using a
3060 preliminary mapping. For example, we put them on 512 MB boundaries
3061 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
3062 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
3063 programmed for SDRAM access. Using the temporary configuration, a
3064 simple memory test is run that determines the size of the SDRAM
3067 When there is more than one SDRAM bank, and the banks are of
3068 different size, the largest is mapped first. For equal size, the first
3069 bank (CS2#) is mapped first. The first mapping is always for address
3070 0x00000000, with any additional banks following immediately to create
3071 contiguous memory starting from 0.
3073 Then, the monitor installs itself at the upper end of the SDRAM area
3074 and allocates memory for use by malloc() and for the global Board
3075 Info data; also, the exception vector code is copied to the low RAM
3076 pages, and the final stack is set up.
3078 Only after this relocation will you have a "normal" C environment;
3079 until that you are restricted in several ways, mostly because you are
3080 running from ROM, and because the code will have to be relocated to a
3084 U-Boot Porting Guide:
3085 ----------------------
3087 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
3091 int main (int argc, char *argv[])
3093 sighandler_t no_more_time;
3095 signal (SIGALRM, no_more_time);
3096 alarm (PROJECT_DEADLINE - toSec (3 * WEEK));
3098 if (available_money > available_manpower) {
3099 pay consultant to port U-Boot;
3103 Download latest U-Boot source;
3105 Subscribe to u-boot-users mailing list;
3108 email ("Hi, I am new to U-Boot, how do I get started?");
3112 Read the README file in the top level directory;
3113 Read http://www.denx.de/twiki/bin/view/DULG/Manual ;
3114 Read the source, Luke;
3117 if (available_money > toLocalCurrency ($2500)) {
3120 Add a lot of aggravation and time;
3123 Create your own board support subdirectory;
3125 Create your own board config file;
3129 Add / modify source code;
3133 email ("Hi, I am having problems...");
3135 Send patch file to Wolfgang;
3140 void no_more_time (int sig)
3149 All contributions to U-Boot should conform to the Linux kernel
3150 coding style; see the file "Documentation/CodingStyle" in your Linux
3151 kernel source directory.
3153 Please note that U-Boot is implemented in C (and to some small parts
3154 in Assembler); no C++ is used, so please do not use C++ style
3155 comments (//) in your code.
3157 Submissions which do not conform to the standards may be returned
3158 with a request to reformat the changes.
3164 Since the number of patches for U-Boot is growing, we need to
3165 establish some rules. Submissions which do not conform to these rules
3166 may be rejected, even when they contain important and valuable stuff.
3169 When you send a patch, please include the following information with
3172 * For bug fixes: a description of the bug and how your patch fixes
3173 this bug. Please try to include a way of demonstrating that the
3174 patch actually fixes something.
3176 * For new features: a description of the feature and your
3179 * A CHANGELOG entry as plaintext (separate from the patch)
3181 * For major contributions, your entry to the CREDITS file
3183 * When you add support for a new board, don't forget to add this
3184 board to the MAKEALL script, too.
3186 * If your patch adds new configuration options, don't forget to
3187 document these in the README file.
3189 * The patch itself. If you are accessing the CVS repository use "cvs
3190 update; cvs diff -puRN"; else, use "diff -purN OLD NEW". If your
3191 version of diff does not support these options, then get the latest
3192 version of GNU diff.
3194 The current directory when running this command shall be the top
3195 level directory of the U-Boot source tree, or it's parent directory
3196 (i. e. please make sure that your patch includes sufficient
3197 directory information for the affected files).
3199 We accept patches as plain text, MIME attachments or as uuencoded
3202 * If one logical set of modifications affects or creates several
3203 files, all these changes shall be submitted in a SINGLE patch file.
3205 * Changesets that contain different, unrelated modifications shall be
3206 submitted as SEPARATE patches, one patch per changeset.
3211 * Before sending the patch, run the MAKEALL script on your patched
3212 source tree and make sure that no errors or warnings are reported
3213 for any of the boards.
3215 * Keep your modifications to the necessary minimum: A patch
3216 containing several unrelated changes or arbitrary reformats will be
3217 returned with a request to re-formatting / split it.
3219 * If you modify existing code, make sure that your new code does not
3220 add to the memory footprint of the code ;-) Small is beautiful!
3221 When adding new features, these should compile conditionally only
3222 (using #ifdef), and the resulting code with the new feature
3223 disabled must not need more memory than the old code without your
projects / platform / kernel / u-boot.git / blob