1# 2# (C) Copyright 2000 - 2002 3# Wolfgang Denk, DENX Software Engineering, wd@denx.de. 4# 5# See file CREDITS for list of people who contributed to this 6# project. 7# 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. 12# 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. 17# 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, 21# MA 02111-1307 USA 22# 23 24Summary: 25======== 26 27This directory contains the source code for U-Boot, a boot loader for 28Embedded boards based on PowerPC and ARM processors, which can be 29installed in a boot ROM and used to initialize and test the hardware 30or to download and run application code. 31 32The development of U-Boot is closely related to Linux: some parts of 33the source code originate in the Linux source tree, we have some 34header files in common, and special provision has been made to 35support booting of Linux images. 36 37Some attention has been paid to make this software easily 38configurable and extendable. For instance, all monitor commands are 39implemented with the same call interface, so that it's very easy to 40add new commands. Also, instead of permanently adding rarely used 41code (for instance hardware test utilities) to the monitor, you can 42load and run it dynamically. 43 44 45Status: 46======= 47 48In general, all boards for which a configuration option exists in the 49Makefile have been tested to some extent and can be considered 50"working". In fact, many of them are used in production systems. 51 52In case of problems see the CHANGELOG and CREDITS files to find out 53who contributed the specific port. 54 55 56Where to get help: 57================== 58 59In case you have questions about, problems with or contributions for 60U-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 62previous traffic on the mailing list - please search the archive 63before asking FAQ's. Please see 64http://lists.sourceforge.net/lists/listinfo/u-boot-users/ 65 66 67Where we come from: 68=================== 69 70- start from 8xxrom sources 71- create PPCBoot project (http://sourceforge.net/projects/ppcboot) 72- clean up code 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 77 * S-Record download 78 * network boot 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) 83 84 85Names and Spelling: 86=================== 87 88The "official" name of this project is "Das U-Boot". The spelling 89"U-Boot" shall be used in all written text (documentation, comments 90in source files etc.). Example: 91 92 This is the README file for the U-Boot project. 93 94File names etc. shall be based on the string "u-boot". Examples: 95 96 include/asm-ppc/u-boot.h 97 98 #include <asm/u-boot.h> 99 100Variable names, preprocessor constants etc. shall be either based on 101the string "u_boot" or on "U_BOOT". Example: 102 103 U_BOOT_VERSION u_boot_logo 104 IH_OS_U_BOOT u_boot_hush_start 105 106 107Versioning: 108=========== 109 110U-Boot uses a 3 level version number containing a version, a 111sub-version, and a patchlevel: "U-Boot-2.34.5" means version "2", 112sub-version "34", and patchlevel "4". 113 114The patchlevel is used to indicate certain stages of development 115between released versions, i. e. officially released versions of 116U-Boot will always have a patchlevel of "0". 117 118 119Directory Hierarchy: 120==================== 121 122- 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. 141 142- 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/ppc4xx Files specific to IBM 4xx CPUs 150 151 152- board/LEOX/ Files specific to boards manufactured by The LEOX team 153- board/LEOX/elpt860 Files specific to ELPT860 boards 154- board/RPXClassic 155 Files specific to RPXClassic boards 156- board/RPXlite Files specific to RPXlite boards 157- board/at91rm9200dk Files specific to AT91RM9200DK boards 158- board/c2mon Files specific to c2mon boards 159- board/cmi Files specific to cmi boards 160- board/cogent Files specific to Cogent boards 161 (need further configuration) 162 Files specific to CPCIISER4 boards 163- board/cpu86 Files specific to CPU86 boards 164- board/cray/ Files specific to boards manufactured by Cray 165- board/cray/L1 Files specific to L1 boards 166- board/cu824 Files specific to CU824 boards 167- board/ebony Files specific to IBM Ebony board 168- board/eric Files specific to ERIC boards 169- board/esd/ Files specific to boards manufactured by ESD 170- board/esd/adciop Files specific to ADCIOP boards 171- board/esd/ar405 Files specific to AR405 boards 172- board/esd/canbt Files specific to CANBT boards 173- board/esd/cpci405 Files specific to CPCI405 boards 174- board/esd/cpciiser4 Files specific to CPCIISER4 boards 175- board/esd/common Common files for ESD boards 176- board/esd/dasa_sim Files specific to DASA_SIM boards 177- board/esd/du405 Files specific to DU405 boards 178- board/esd/ocrtc Files specific to OCRTC boards 179- board/esd/pci405 Files specific to PCI405 boards 180- board/esteem192e 181 Files specific to ESTEEM192E boards 182- board/etx094 Files specific to ETX_094 boards 183- board/evb64260 184 Files specific to EVB64260 boards 185- board/fads Files specific to FADS boards 186- board/flagadm Files specific to FLAGADM boards 187- board/gen860t Files specific to GEN860T and GEN860T_SC boards 188- board/genietv Files specific to GENIETV boards 189- board/gth Files specific to GTH boards 190- board/hermes Files specific to HERMES boards 191- board/hymod Files specific to HYMOD boards 192- board/icu862 Files specific to ICU862 boards 193- board/ip860 Files specific to IP860 boards 194- board/iphase4539 195 Files specific to Interphase4539 boards 196- board/ivm Files specific to IVMS8/IVML24 boards 197- board/lantec Files specific to LANTEC boards 198- board/lwmon Files specific to LWMON boards 199- board/mbx8xx Files specific to MBX boards 200- board/mpc8260ads 201 Files specific to MPC8260ADS and PQ2FADS-ZU boards 202- board/mpl/ Files specific to boards manufactured by MPL 203- board/mpl/common Common files for MPL boards 204- board/mpl/pip405 Files specific to PIP405 boards 205- board/mpl/mip405 Files specific to MIP405 boards 206- board/mpl/vcma9 Files specific to VCMA9 boards 207- board/musenki Files specific to MUSEKNI boards 208- board/mvs1 Files specific to MVS1 boards 209- board/nx823 Files specific to NX823 boards 210- board/oxc Files specific to OXC boards 211- board/omap1510inn 212 Files specific to OMAP 1510 Innovator boards 213- board/omap1610inn 214 Files specific to OMAP 1610 Innovator boards 215- board/pcippc2 Files specific to PCIPPC2/PCIPPC6 boards 216- board/pm826 Files specific to PM826 boards 217- board/ppmc8260 218 Files specific to PPMC8260 boards 219- board/rpxsuper 220 Files specific to RPXsuper boards 221- board/rsdproto 222 Files specific to RSDproto boards 223- board/sandpoint 224 Files specific to Sandpoint boards 225- board/sbc8260 Files specific to SBC8260 boards 226- board/sacsng Files specific to SACSng boards 227- board/siemens Files specific to boards manufactured by Siemens AG 228- board/siemens/CCM Files specific to CCM boards 229- board/siemens/IAD210 Files specific to IAD210 boards 230- board/siemens/SCM Files specific to SCM boards 231- board/siemens/pcu_e Files specific to PCU_E boards 232- board/sixnet Files specific to SIXNET boards 233- board/spd8xx Files specific to SPD8xxTS boards 234- board/tqm8260 Files specific to TQM8260 boards 235- board/tqm8xx Files specific to TQM8xxL boards 236- board/w7o Files specific to W7O boards 237- board/walnut405 238 Files specific to Walnut405 boards 239- board/westel/ Files specific to boards manufactured by Westel Wireless 240- board/westel/amx860 Files specific to AMX860 boards 241- board/utx8245 Files specific to UTX8245 boards 242- board/zpc1900 Files specific to Zephyr Engineering ZPC.1900 board 243 244Software Configuration: 245======================= 246 247Configuration is usually done using C preprocessor defines; the 248rationale behind that is to avoid dead code whenever possible. 249 250There are two classes of configuration variables: 251 252* Configuration _OPTIONS_: 253 These are selectable by the user and have names beginning with 254 "CONFIG_". 255 256* Configuration _SETTINGS_: 257 These depend on the hardware etc. and should not be meddled with if 258 you don't know what you're doing; they have names beginning with 259 "CFG_". 260 261Later we will add a configuration tool - probably similar to or even 262identical to what's used for the Linux kernel. Right now, we have to 263do the configuration by hand, which means creating some symbolic 264links and editing some configuration files. We use the TQM8xxL boards 265as an example here. 266 267 268Selection of Processor Architecture and Board Type: 269--------------------------------------------------- 270 271For all supported boards there are ready-to-use default 272configurations available; just type "make <board_name>_config". 273 274Example: For a TQM823L module type: 275 276 cd u-boot 277 make TQM823L_config 278 279For the Cogent platform, you need to specify the cpu type as well; 280e.g. "make cogent_mpc8xx_config". And also configure the cogent 281directory according to the instructions in cogent/README. 282 283 284Configuration Options: 285---------------------- 286 287Configuration depends on the combination of board and CPU type; all 288such information is kept in a configuration file 289"include/configs/<board_name>.h". 290 291Example: For a TQM823L module, all configuration settings are in 292"include/configs/TQM823L.h". 293 294 295Many of the options are named exactly as the corresponding Linux 296kernel configuration options. The intention is to make it easier to 297build a config tool - later. 298 299 300The following options need to be configured: 301 302- CPU Type: Define exactly one of 303 304 PowerPC based CPUs: 305 ------------------- 306 CONFIG_MPC823, CONFIG_MPC850, CONFIG_MPC855, CONFIG_MPC860 307 or CONFIG_MPC5xx 308 or CONFIG_MPC824X, CONFIG_MPC8260 309 or CONFIG_IOP480 310 or CONFIG_405GP 311 or CONFIG_405EP 312 or CONFIG_440 313 or CONFIG_MPC74xx 314 or CONFIG_750FX 315 316 ARM based CPUs: 317 --------------- 318 CONFIG_SA1110 319 CONFIG_ARM7 320 CONFIG_PXA250 321 322 323- Board Type: Define exactly one of 324 325 PowerPC based boards: 326 --------------------- 327 328 CONFIG_ADCIOP, CONFIG_ICU862 CONFIG_RPXsuper, 329 CONFIG_ADS860, CONFIG_IP860, CONFIG_SM850, 330 CONFIG_AMX860, CONFIG_IPHASE4539, CONFIG_SPD823TS, 331 CONFIG_AR405, CONFIG_IVML24, CONFIG_SXNI855T, 332 CONFIG_BAB7xx, CONFIG_IVML24_128, CONFIG_Sandpoint8240, 333 CONFIG_CANBT, CONFIG_IVML24_256, CONFIG_Sandpoint8245, 334 CONFIG_CCM, CONFIG_IVMS8, CONFIG_TQM823L, 335 CONFIG_CPCI405, CONFIG_IVMS8_128, CONFIG_TQM850L, 336 CONFIG_CPCI4052, CONFIG_IVMS8_256, CONFIG_TQM855L, 337 CONFIG_CPCIISER4, CONFIG_LANTEC, CONFIG_TQM860L, 338 CONFIG_CPU86, CONFIG_MBX, CONFIG_TQM8260, 339 CONFIG_CRAYL1, CONFIG_MBX860T, CONFIG_TTTech, 340 CONFIG_CU824, CONFIG_MHPC, CONFIG_UTX8245, 341 CONFIG_DASA_SIM, CONFIG_MIP405, CONFIG_W7OLMC, 342 CONFIG_DU405, CONFIG_MOUSSE, CONFIG_W7OLMG, 343 CONFIG_ELPPC, CONFIG_MPC8260ADS, CONFIG_WALNUT405, 344 CONFIG_ERIC, CONFIG_MUSENKI, CONFIG_ZUMA, 345 CONFIG_ESTEEM192E, CONFIG_MVS1, CONFIG_c2mon, 346 CONFIG_ETX094, CONFIG_NX823, CONFIG_cogent_mpc8260, 347 CONFIG_EVB64260, CONFIG_OCRTC, CONFIG_cogent_mpc8xx, 348 CONFIG_FADS823, CONFIG_ORSG, CONFIG_ep8260, 349 CONFIG_FADS850SAR, CONFIG_OXC, CONFIG_gw8260, 350 CONFIG_FADS860T, CONFIG_PCI405, CONFIG_hermes, 351 CONFIG_FLAGADM, CONFIG_PCIPPC2, CONFIG_hymod, 352 CONFIG_FPS850L, CONFIG_PCIPPC6, CONFIG_lwmon, 353 CONFIG_GEN860T, CONFIG_PIP405, CONFIG_pcu_e, 354 CONFIG_GENIETV, CONFIG_PM826, CONFIG_ppmc8260, 355 CONFIG_GTH, CONFIG_RPXClassic, CONFIG_rsdproto, 356 CONFIG_IAD210, CONFIG_RPXlite, CONFIG_sbc8260, 357 CONFIG_EBONY, CONFIG_sacsng, CONFIG_FPS860L, 358 CONFIG_V37, CONFIG_ELPT860, CONFIG_CMI, 359 CONFIG_NETVIA, CONFIG_RBC823, CONFIG_ZPC1900 360 361 ARM based boards: 362 ----------------- 363 364 CONFIG_HHP_CRADLE, CONFIG_DNP1110, CONFIG_EP7312, 365 CONFIG_IMPA7, CONFIG_LART, CONFIG_LUBBOCK, 366 CONFIG_INNOVATOROMAP1510, CONFIG_INNOVATOROMAP1610 367 CONFIG_SHANNON, CONFIG_SMDK2400, CONFIG_SMDK2410, 368 CONFIG_TRAB, CONFIG_VCMA9, CONFIG_AT91RM9200DK 369 370 371- CPU Module Type: (if CONFIG_COGENT is defined) 372 Define exactly one of 373 CONFIG_CMA286_60_OLD 374--- FIXME --- not tested yet: 375 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P, 376 CONFIG_CMA287_23, CONFIG_CMA287_50 377 378- Motherboard Type: (if CONFIG_COGENT is defined) 379 Define exactly one of 380 CONFIG_CMA101, CONFIG_CMA102 381 382- Motherboard I/O Modules: (if CONFIG_COGENT is defined) 383 Define one or more of 384 CONFIG_CMA302 385 386- Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined) 387 Define one or more of 388 CONFIG_LCD_HEARTBEAT - update a character position on 389 the lcd display every second with 390 a "rotator" |\-/|\-/ 391 392- Board flavour: (if CONFIG_MPC8260ADS is defined) 393 CONFIG_ADSTYPE 394 Possible values are: 395 CFG_8260ADS - original MPC8260ADS 396 CFG_8266ADS - MPC8266ADS (untested) 397 CFG_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR 398 399 400- MPC824X Family Member (if CONFIG_MPC824X is defined) 401 Define exactly one of 402 CONFIG_MPC8240, CONFIG_MPC8245 403 404- 8xx CPU Options: (if using an 8xx cpu) 405 Define one or more of 406 CONFIG_8xx_GCLK_FREQ - if get_gclk_freq() cannot work 407 e.g. if there is no 32KHz 408 reference PIT/RTC clock 409 410- Linux Kernel Interface: 411 CONFIG_CLOCKS_IN_MHZ 412 413 U-Boot stores all clock information in Hz 414 internally. For binary compatibility with older Linux 415 kernels (which expect the clocks passed in the 416 bd_info data to be in MHz) the environment variable 417 "clocks_in_mhz" can be defined so that U-Boot 418 converts clock data to MHZ before passing it to the 419 Linux kernel. 420 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of 421 "clocks_in_mhz=1" is automatically included in the 422 default environment. 423 424 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only] 425 426 When transfering memsize parameter to linux, some versions 427 expect it to be in bytes, others in MB. 428 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes. 429 430- Console Interface: 431 Depending on board, define exactly one serial port 432 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2, 433 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial 434 console by defining CONFIG_8xx_CONS_NONE 435 436 Note: if CONFIG_8xx_CONS_NONE is defined, the serial 437 port routines must be defined elsewhere 438 (i.e. serial_init(), serial_getc(), ...) 439 440 CONFIG_CFB_CONSOLE 441 Enables console device for a color framebuffer. Needs following 442 defines (cf. smiLynxEM, i8042, board/eltec/bab7xx) 443 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation 444 (default big endian) 445 VIDEO_HW_RECTFILL graphic chip supports 446 rectangle fill 447 (cf. smiLynxEM) 448 VIDEO_HW_BITBLT graphic chip supports 449 bit-blit (cf. smiLynxEM) 450 VIDEO_VISIBLE_COLS visible pixel columns 451 (cols=pitch) 452 VIDEO_VISIBLE_ROWS visible pixel rows 453 VIDEO_PIXEL_SIZE bytes per pixel 454 VIDEO_DATA_FORMAT graphic data format 455 (0-5, cf. cfb_console.c) 456 VIDEO_FB_ADRS framebuffer address 457 VIDEO_KBD_INIT_FCT keyboard int fct 458 (i.e. i8042_kbd_init()) 459 VIDEO_TSTC_FCT test char fct 460 (i.e. i8042_tstc) 461 VIDEO_GETC_FCT get char fct 462 (i.e. i8042_getc) 463 CONFIG_CONSOLE_CURSOR cursor drawing on/off 464 (requires blink timer 465 cf. i8042.c) 466 CFG_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c) 467 CONFIG_CONSOLE_TIME display time/date info in 468 upper right corner 469 (requires CFG_CMD_DATE) 470 CONFIG_VIDEO_LOGO display Linux logo in 471 upper left corner 472 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of 473 linux_logo.h for logo. 474 Requires CONFIG_VIDEO_LOGO 475 CONFIG_CONSOLE_EXTRA_INFO 476 addional board info beside 477 the logo 478 479 When CONFIG_CFB_CONSOLE is defined, video console is 480 default i/o. Serial console can be forced with 481 environment 'console=serial'. 482 483- Console Baudrate: 484 CONFIG_BAUDRATE - in bps 485 Select one of the baudrates listed in 486 CFG_BAUDRATE_TABLE, see below. 487 488- Interrupt driven serial port input: 489 CONFIG_SERIAL_SOFTWARE_FIFO 490 491 PPC405GP only. 492 Use an interrupt handler for receiving data on the 493 serial port. It also enables using hardware handshake 494 (RTS/CTS) and UART's built-in FIFO. Set the number of 495 bytes the interrupt driven input buffer should have. 496 497 Set to 0 to disable this feature (this is the default). 498 This will also disable hardware handshake. 499 500- Console UART Number: 501 CONFIG_UART1_CONSOLE 502 503 IBM PPC4xx only. 504 If defined internal UART1 (and not UART0) is used 505 as default U-Boot console. 506 507- Boot Delay: CONFIG_BOOTDELAY - in seconds 508 Delay before automatically booting the default image; 509 set to -1 to disable autoboot. 510 511 See doc/README.autoboot for these options that 512 work with CONFIG_BOOTDELAY. None are required. 513 CONFIG_BOOT_RETRY_TIME 514 CONFIG_BOOT_RETRY_MIN 515 CONFIG_AUTOBOOT_KEYED 516 CONFIG_AUTOBOOT_PROMPT 517 CONFIG_AUTOBOOT_DELAY_STR 518 CONFIG_AUTOBOOT_STOP_STR 519 CONFIG_AUTOBOOT_DELAY_STR2 520 CONFIG_AUTOBOOT_STOP_STR2 521 CONFIG_ZERO_BOOTDELAY_CHECK 522 CONFIG_RESET_TO_RETRY 523 524- Autoboot Command: 525 CONFIG_BOOTCOMMAND 526 Only needed when CONFIG_BOOTDELAY is enabled; 527 define a command string that is automatically executed 528 when no character is read on the console interface 529 within "Boot Delay" after reset. 530 531 CONFIG_BOOTARGS 532 This can be used to pass arguments to the bootm 533 command. The value of CONFIG_BOOTARGS goes into the 534 environment value "bootargs". 535 536 CONFIG_RAMBOOT and CONFIG_NFSBOOT 537 The value of these goes into the environment as 538 "ramboot" and "nfsboot" respectively, and can be used 539 as a convenience, when switching between booting from 540 ram and nfs. 541 542- Pre-Boot Commands: 543 CONFIG_PREBOOT 544 545 When this option is #defined, the existence of the 546 environment variable "preboot" will be checked 547 immediately before starting the CONFIG_BOOTDELAY 548 countdown and/or running the auto-boot command resp. 549 entering interactive mode. 550 551 This feature is especially useful when "preboot" is 552 automatically generated or modified. For an example 553 see the LWMON board specific code: here "preboot" is 554 modified when the user holds down a certain 555 combination of keys on the (special) keyboard when 556 booting the systems 557 558- Serial Download Echo Mode: 559 CONFIG_LOADS_ECHO 560 If defined to 1, all characters received during a 561 serial download (using the "loads" command) are 562 echoed back. This might be needed by some terminal 563 emulations (like "cu"), but may as well just take 564 time on others. This setting #define's the initial 565 value of the "loads_echo" environment variable. 566 567- Kgdb Serial Baudrate: (if CFG_CMD_KGDB is defined) 568 CONFIG_KGDB_BAUDRATE 569 Select one of the baudrates listed in 570 CFG_BAUDRATE_TABLE, see below. 571 572- Monitor Functions: 573 CONFIG_COMMANDS 574 Most monitor functions can be selected (or 575 de-selected) by adjusting the definition of 576 CONFIG_COMMANDS; to select individual functions, 577 #define CONFIG_COMMANDS by "OR"ing any of the 578 following values: 579 580 #define enables commands: 581 ------------------------- 582 CFG_CMD_ASKENV * ask for env variable 583 CFG_CMD_AUTOSCRIPT Autoscript Support 584 CFG_CMD_BDI bdinfo 585 CFG_CMD_BEDBUG Include BedBug Debugger 586 CFG_CMD_BMP * BMP support 587 CFG_CMD_BOOTD bootd 588 CFG_CMD_CACHE icache, dcache 589 CFG_CMD_CONSOLE coninfo 590 CFG_CMD_DATE * support for RTC, date/time... 591 CFG_CMD_DHCP DHCP support 592 CFG_CMD_DIAG * Diagnostics 593 CFG_CMD_DOC * Disk-On-Chip Support 594 CFG_CMD_DTT Digital Therm and Thermostat 595 CFG_CMD_ECHO * echo arguments 596 CFG_CMD_EEPROM * EEPROM read/write support 597 CFG_CMD_ELF bootelf, bootvx 598 CFG_CMD_ENV saveenv 599 CFG_CMD_FDC * Floppy Disk Support 600 CFG_CMD_FAT FAT partition support 601 CFG_CMD_FDOS * Dos diskette Support 602 CFG_CMD_FLASH flinfo, erase, protect 603 CFG_CMD_FPGA FPGA device initialization support 604 CFG_CMD_HWFLOW * RTS/CTS hw flow control 605 CFG_CMD_I2C * I2C serial bus support 606 CFG_CMD_IDE * IDE harddisk support 607 CFG_CMD_IMI iminfo 608 CFG_CMD_IMLS List all found images 609 CFG_CMD_IMMAP * IMMR dump support 610 CFG_CMD_IRQ * irqinfo 611 CFG_CMD_JFFS2 * JFFS2 Support 612 CFG_CMD_KGDB * kgdb 613 CFG_CMD_LOADB loadb 614 CFG_CMD_LOADS loads 615 CFG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base, 616 loop, mtest 617 CFG_CMD_MISC Misc functions like sleep etc 618 CFG_CMD_MMC MMC memory mapped support 619 CFG_CMD_MII MII utility commands 620 CFG_CMD_NAND * NAND support 621 CFG_CMD_NET bootp, tftpboot, rarpboot 622 CFG_CMD_PCI * pciinfo 623 CFG_CMD_PCMCIA * PCMCIA support 624 CFG_CMD_PING * send ICMP ECHO_REQUEST to network host 625 CFG_CMD_PORTIO Port I/O 626 CFG_CMD_REGINFO * Register dump 627 CFG_CMD_RUN run command in env variable 628 CFG_CMD_SAVES save S record dump 629 CFG_CMD_SCSI * SCSI Support 630 CFG_CMD_SDRAM * print SDRAM configuration information 631 CFG_CMD_SETGETDCR Support for DCR Register access (4xx only) 632 CFG_CMD_SPI * SPI serial bus support 633 CFG_CMD_USB * USB support 634 CFG_CMD_VFD * VFD support (TRAB) 635 CFG_CMD_BSP * Board SPecific functions 636 ----------------------------------------------- 637 CFG_CMD_ALL all 638 639 CFG_CMD_DFL Default configuration; at the moment 640 this is includes all commands, except 641 the ones marked with "*" in the list 642 above. 643 644 If you don't define CONFIG_COMMANDS it defaults to 645 CFG_CMD_DFL in include/cmd_confdefs.h. A board can 646 override the default settings in the respective 647 include file. 648 649 EXAMPLE: If you want all functions except of network 650 support you can write: 651 652 #define CONFIG_COMMANDS (CFG_CMD_ALL & ~CFG_CMD_NET) 653 654 655 Note: Don't enable the "icache" and "dcache" commands 656 (configuration option CFG_CMD_CACHE) unless you know 657 what you (and your U-Boot users) are doing. Data 658 cache cannot be enabled on systems like the 8xx or 659 8260 (where accesses to the IMMR region must be 660 uncached), and it cannot be disabled on all other 661 systems where we (mis-) use the data cache to hold an 662 initial stack and some data. 663 664 665 XXX - this list needs to get updated! 666 667- Watchdog: 668 CONFIG_WATCHDOG 669 If this variable is defined, it enables watchdog 670 support. There must be support in the platform specific 671 code for a watchdog. For the 8xx and 8260 CPUs, the 672 SIU Watchdog feature is enabled in the SYPCR 673 register. 674 675- U-Boot Version: 676 CONFIG_VERSION_VARIABLE 677 If this variable is defined, an environment variable 678 named "ver" is created by U-Boot showing the U-Boot 679 version as printed by the "version" command. 680 This variable is readonly. 681 682- Real-Time Clock: 683 684 When CFG_CMD_DATE is selected, the type of the RTC 685 has to be selected, too. Define exactly one of the 686 following options: 687 688 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx 689 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC 690 CONFIG_RTC_MC146818 - use MC146818 RTC 691 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC 692 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC 693 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC 694 CONFIG_RTC_DS164x - use Dallas DS164x RTC 695 696 Note that if the RTC uses I2C, then the I2C interface 697 must also be configured. See I2C Support, below. 698 699- Timestamp Support: 700 701 When CONFIG_TIMESTAMP is selected, the timestamp 702 (date and time) of an image is printed by image 703 commands like bootm or iminfo. This option is 704 automatically enabled when you select CFG_CMD_DATE . 705 706- Partition Support: 707 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION 708 and/or CONFIG_ISO_PARTITION 709 710 If IDE or SCSI support is enabled (CFG_CMD_IDE or 711 CFG_CMD_SCSI) you must configure support for at least 712 one partition type as well. 713 714- IDE Reset method: 715 CONFIG_IDE_RESET_ROUTINE 716 717 Set this to define that instead of a reset Pin, the 718 routine ide_set_reset(int idereset) will be used. 719 720- ATAPI Support: 721 CONFIG_ATAPI 722 723 Set this to enable ATAPI support. 724 725- SCSI Support: 726 At the moment only there is only support for the 727 SYM53C8XX SCSI controller; define 728 CONFIG_SCSI_SYM53C8XX to enable it. 729 730 CFG_SCSI_MAX_LUN [8], CFG_SCSI_MAX_SCSI_ID [7] and 731 CFG_SCSI_MAX_DEVICE [CFG_SCSI_MAX_SCSI_ID * 732 CFG_SCSI_MAX_LUN] can be adjusted to define the 733 maximum numbers of LUNs, SCSI ID's and target 734 devices. 735 CFG_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz) 736 737- NETWORK Support (PCI): 738 CONFIG_E1000 739 Support for Intel 8254x gigabit chips. 740 741 CONFIG_EEPRO100 742 Support for Intel 82557/82559/82559ER chips. 743 Optional CONFIG_EEPRO100_SROM_WRITE enables eeprom 744 write routine for first time initialisation. 745 746 CONFIG_TULIP 747 Support for Digital 2114x chips. 748 Optional CONFIG_TULIP_SELECT_MEDIA for board specific 749 modem chip initialisation (KS8761/QS6611). 750 751 CONFIG_NATSEMI 752 Support for National dp83815 chips. 753 754 CONFIG_NS8382X 755 Support for National dp8382[01] gigabit chips. 756 757- NETWORK Support (other): 758 759 CONFIG_DRIVER_LAN91C96 760 Support for SMSC's LAN91C96 chips. 761 762 CONFIG_LAN91C96_BASE 763 Define this to hold the physical address 764 of the LAN91C96's I/O space 765 766 CONFIG_LAN91C96_USE_32_BIT 767 Define this to enable 32 bit addressing 768 769- USB Support: 770 At the moment only the UHCI host controller is 771 supported (PIP405, MIP405); define 772 CONFIG_USB_UHCI to enable it. 773 define CONFIG_USB_KEYBOARD to enable the USB Keyboard 774 end define CONFIG_USB_STORAGE to enable the USB 775 storage devices. 776 Note: 777 Supported are USB Keyboards and USB Floppy drives 778 (TEAC FD-05PUB). 779 780- MMC Support: 781 The MMC controller on the Intel PXA is supported. To 782 enable this define CONFIG_MMC. The MMC can be 783 accessed from the boot prompt by mapping the device 784 to physical memory similar to flash. Command line is 785 enabled with CFG_CMD_MMC. The MMC driver also works with 786 the FAT fs. This is enabled with CFG_CMD_FAT. 787 788- Keyboard Support: 789 CONFIG_ISA_KEYBOARD 790 791 Define this to enable standard (PC-Style) keyboard 792 support 793 794 CONFIG_I8042_KBD 795 Standard PC keyboard driver with US (is default) and 796 GERMAN key layout (switch via environment 'keymap=de') support. 797 Export function i8042_kbd_init, i8042_tstc and i8042_getc 798 for cfb_console. Supports cursor blinking. 799 800- Video support: 801 CONFIG_VIDEO 802 803 Define this to enable video support (for output to 804 video). 805 806 CONFIG_VIDEO_CT69000 807 808 Enable Chips & Technologies 69000 Video chip 809 810 CONFIG_VIDEO_SMI_LYNXEM 811 Enable Silicon Motion SMI 712/710/810 Video chip 812 Videomode are selected via environment 'videomode' with 813 standard LiLo mode numbers. 814 Following modes are supported (* is default): 815 816 800x600 1024x768 1280x1024 817 256 (8bit) 303* 305 307 818 65536 (16bit) 314 317 31a 819 16,7 Mill (24bit) 315 318 31b 820 (i.e. setenv videomode 317; saveenv; reset;) 821 822 CONFIG_VIDEO_SED13806 823 Enable Epson SED13806 driver. This driver supports 8bpp 824 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP 825 or CONFIG_VIDEO_SED13806_16BPP 826 827- Keyboard Support: 828 CONFIG_KEYBOARD 829 830 Define this to enable a custom keyboard support. 831 This simply calls drv_keyboard_init() which must be 832 defined in your board-specific files. 833 The only board using this so far is RBC823. 834 835- LCD Support: CONFIG_LCD 836 837 Define this to enable LCD support (for output to LCD 838 display); also select one of the supported displays 839 by defining one of these: 840 841 CONFIG_NEC_NL6648AC33: 842 843 NEC NL6648AC33-18. Active, color, single scan. 844 845 CONFIG_NEC_NL6648BC20 846 847 NEC NL6648BC20-08. 6.5", 640x480. 848 Active, color, single scan. 849 850 CONFIG_SHARP_16x9 851 852 Sharp 320x240. Active, color, single scan. 853 It isn't 16x9, and I am not sure what it is. 854 855 CONFIG_SHARP_LQ64D341 856 857 Sharp LQ64D341 display, 640x480. 858 Active, color, single scan. 859 860 CONFIG_HLD1045 861 862 HLD1045 display, 640x480. 863 Active, color, single scan. 864 865 CONFIG_OPTREX_BW 866 867 Optrex CBL50840-2 NF-FW 99 22 M5 868 or 869 Hitachi LMG6912RPFC-00T 870 or 871 Hitachi SP14Q002 872 873 320x240. Black & white. 874 875 Normally display is black on white background; define 876 CFG_WHITE_ON_BLACK to get it inverted. 877 878- Splash Screen Support: CONFIG_SPLASH_SCREEN 879 880 If this option is set, the environment is checked for 881 a variable "splashimage". If found, the usual display 882 of logo, copyright and system information on the LCD 883 is supressed and the BMP image at the address 884 specified in "splashimage" is loaded instead. The 885 console is redirected to the "nulldev", too. This 886 allows for a "silent" boot where a splash screen is 887 loaded very quickly after power-on. 888 889- Compression support: 890 CONFIG_BZIP2 891 892 If this option is set, support for bzip2 compressed 893 images is included. If not, only uncompressed and gzip 894 compressed images are supported. 895 896 NOTE: the bzip2 algorithm requires a lot of RAM, so 897 the malloc area (as defined by CFG_MALLOC_LEN) should 898 be at least 4MB. 899 900- Ethernet address: 901 CONFIG_ETHADDR 902 CONFIG_ETH2ADDR 903 CONFIG_ETH3ADDR 904 905 Define a default value for ethernet address to use 906 for the respective ethernet interface, in case this 907 is not determined automatically. 908 909- IP address: 910 CONFIG_IPADDR 911 912 Define a default value for the IP address to use for 913 the default ethernet interface, in case this is not 914 determined through e.g. bootp. 915 916- Server IP address: 917 CONFIG_SERVERIP 918 919 Defines a default value for theIP address of a TFTP 920 server to contact when using the "tftboot" command. 921 922- BOOTP Recovery Mode: 923 CONFIG_BOOTP_RANDOM_DELAY 924 925 If you have many targets in a network that try to 926 boot using BOOTP, you may want to avoid that all 927 systems send out BOOTP requests at precisely the same 928 moment (which would happen for instance at recovery 929 from a power failure, when all systems will try to 930 boot, thus flooding the BOOTP server. Defining 931 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 932 inserted before sending out BOOTP requests. The 933 following delays are insterted then: 934 935 1st BOOTP request: delay 0 ... 1 sec 936 2nd BOOTP request: delay 0 ... 2 sec 937 3rd BOOTP request: delay 0 ... 4 sec 938 4th and following 939 BOOTP requests: delay 0 ... 8 sec 940 941- DHCP Advanced Options: 942 CONFIG_BOOTP_MASK 943 944 You can fine tune the DHCP functionality by adding 945 these flags to the CONFIG_BOOTP_MASK define: 946 947 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS 948 serverip from a DHCP server, it is possible that more 949 than one DNS serverip is offered to the client. 950 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS 951 serverip will be stored in the additional environment 952 variable "dnsip2". The first DNS serverip is always 953 stored in the variable "dnsip", when CONFIG_BOOTP_DNS 954 is added to the CONFIG_BOOTP_MASK. 955 956 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable 957 to do a dynamic update of a DNS server. To do this, they 958 need the hostname of the DHCP requester. 959 If CONFIG_BOOP_SEND_HOSTNAME is added to the 960 CONFIG_BOOTP_MASK, the content of the "hostname" 961 environment variable is passed as option 12 to 962 the DHCP server. 963 964- Status LED: CONFIG_STATUS_LED 965 966 Several configurations allow to display the current 967 status using a LED. For instance, the LED will blink 968 fast while running U-Boot code, stop blinking as 969 soon as a reply to a BOOTP request was received, and 970 start blinking slow once the Linux kernel is running 971 (supported by a status LED driver in the Linux 972 kernel). Defining CONFIG_STATUS_LED enables this 973 feature in U-Boot. 974 975- CAN Support: CONFIG_CAN_DRIVER 976 977 Defining CONFIG_CAN_DRIVER enables CAN driver support 978 on those systems that support this (optional) 979 feature, like the TQM8xxL modules. 980 981- I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C 982 983 These enable I2C serial bus commands. Defining either of 984 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will 985 include the appropriate I2C driver for the selected cpu. 986 987 This will allow you to use i2c commands at the u-boot 988 command line (as long as you set CFG_CMD_I2C in 989 CONFIG_COMMANDS) and communicate with i2c based realtime 990 clock chips. See common/cmd_i2c.c for a description of the 991 command line interface. 992 993 CONFIG_HARD_I2C selects the CPM hardware driver for I2C. 994 995 CONFIG_SOFT_I2C configures u-boot to use a software (aka 996 bit-banging) driver instead of CPM or similar hardware 997 support for I2C. 998 999 There are several other quantities that must also be 1000 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C. 1001 1002 In both cases you will need to define CFG_I2C_SPEED 1003 to be the frequency (in Hz) at which you wish your i2c bus 1004 to run and CFG_I2C_SLAVE to be the address of this node (ie 1005 the cpu's i2c node address). 1006 1007 Now, the u-boot i2c code for the mpc8xx (cpu/mpc8xx/i2c.c) 1008 sets the cpu up as a master node and so its address should 1009 therefore be cleared to 0 (See, eg, MPC823e User's Manual 1010 p.16-473). So, set CFG_I2C_SLAVE to 0. 1011 1012 That's all that's required for CONFIG_HARD_I2C. 1013 1014 If you use the software i2c interface (CONFIG_SOFT_I2C) 1015 then the following macros need to be defined (examples are 1016 from include/configs/lwmon.h): 1017 1018 I2C_INIT 1019 1020 (Optional). Any commands necessary to enable the I2C 1021 controller or configure ports. 1022 1023 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) 1024 1025 I2C_PORT 1026 1027 (Only for MPC8260 CPU). The I/O port to use (the code 1028 assumes both bits are on the same port). Valid values 1029 are 0..3 for ports A..D. 1030 1031 I2C_ACTIVE 1032 1033 The code necessary to make the I2C data line active 1034 (driven). If the data line is open collector, this 1035 define can be null. 1036 1037 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) 1038 1039 I2C_TRISTATE 1040 1041 The code necessary to make the I2C data line tri-stated 1042 (inactive). If the data line is open collector, this 1043 define can be null. 1044 1045 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) 1046 1047 I2C_READ 1048 1049 Code that returns TRUE if the I2C data line is high, 1050 FALSE if it is low. 1051 1052 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) 1053 1054 I2C_SDA(bit) 1055 1056 If <bit> is TRUE, sets the I2C data line high. If it 1057 is FALSE, it clears it (low). 1058 1059 eg: #define I2C_SDA(bit) \ 1060 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ 1061 else immr->im_cpm.cp_pbdat &= ~PB_SDA 1062 1063 I2C_SCL(bit) 1064 1065 If <bit> is TRUE, sets the I2C clock line high. If it 1066 is FALSE, it clears it (low). 1067 1068 eg: #define I2C_SCL(bit) \ 1069 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ 1070 else immr->im_cpm.cp_pbdat &= ~PB_SCL 1071 1072 I2C_DELAY 1073 1074 This delay is invoked four times per clock cycle so this 1075 controls the rate of data transfer. The data rate thus 1076 is 1 / (I2C_DELAY * 4). Often defined to be something 1077 like: 1078 1079 #define I2C_DELAY udelay(2) 1080 1081 CFG_I2C_INIT_BOARD 1082 1083 When a board is reset during an i2c bus transfer 1084 chips might think that the current transfer is still 1085 in progress. On some boards it is possible to access 1086 the i2c SCLK line directly, either by using the 1087 processor pin as a GPIO or by having a second pin 1088 connected to the bus. If this option is defined a 1089 custom i2c_init_board() routine in boards/xxx/board.c 1090 is run early in the boot sequence. 1091 1092- SPI Support: CONFIG_SPI 1093 1094 Enables SPI driver (so far only tested with 1095 SPI EEPROM, also an instance works with Crystal A/D and 1096 D/As on the SACSng board) 1097 1098 CONFIG_SPI_X 1099 1100 Enables extended (16-bit) SPI EEPROM addressing. 1101 (symmetrical to CONFIG_I2C_X) 1102 1103 CONFIG_SOFT_SPI 1104 1105 Enables a software (bit-bang) SPI driver rather than 1106 using hardware support. This is a general purpose 1107 driver that only requires three general I/O port pins 1108 (two outputs, one input) to function. If this is 1109 defined, the board configuration must define several 1110 SPI configuration items (port pins to use, etc). For 1111 an example, see include/configs/sacsng.h. 1112 1113- FPGA Support: CONFIG_FPGA_COUNT 1114 1115 Specify the number of FPGA devices to support. 1116 1117 CONFIG_FPGA 1118 1119 Used to specify the types of FPGA devices. For 1120 example, 1121 #define CONFIG_FPGA CFG_XILINX_VIRTEX2 1122 1123 CFG_FPGA_PROG_FEEDBACK 1124 1125 Enable printing of hash marks during FPGA 1126 configuration. 1127 1128 CFG_FPGA_CHECK_BUSY 1129 1130 Enable checks on FPGA configuration interface busy 1131 status by the configuration function. This option 1132 will require a board or device specific function to 1133 be written. 1134 1135 CONFIG_FPGA_DELAY 1136 1137 If defined, a function that provides delays in the 1138 FPGA configuration driver. 1139 1140 CFG_FPGA_CHECK_CTRLC 1141 1142 Allow Control-C to interrupt FPGA configuration 1143 1144 CFG_FPGA_CHECK_ERROR 1145 1146 Check for configuration errors during FPGA bitfile 1147 loading. For example, abort during Virtex II 1148 configuration if the INIT_B line goes low (which 1149 indicated a CRC error). 1150 1151 CFG_FPGA_WAIT_INIT 1152 1153 Maximum time to wait for the INIT_B line to deassert 1154 after PROB_B has been deasserted during a Virtex II 1155 FPGA configuration sequence. The default time is 500 mS. 1156 1157 CFG_FPGA_WAIT_BUSY 1158 1159 Maximum time to wait for BUSY to deassert during 1160 Virtex II FPGA configuration. The default is 5 mS. 1161 1162 CFG_FPGA_WAIT_CONFIG 1163 1164 Time to wait after FPGA configuration. The default is 1165 200 mS. 1166 1167- FPGA Support: CONFIG_FPGA_COUNT 1168 1169 Specify the number of FPGA devices to support. 1170 1171 CONFIG_FPGA 1172 1173 Used to specify the types of FPGA devices. For example, 1174 #define CONFIG_FPGA CFG_XILINX_VIRTEX2 1175 1176 CFG_FPGA_PROG_FEEDBACK 1177 1178 Enable printing of hash marks during FPGA configuration. 1179 1180 CFG_FPGA_CHECK_BUSY 1181 1182 Enable checks on FPGA configuration interface busy 1183 status by the configuration function. This option 1184 will require a board or device specific function to 1185 be written. 1186 1187 CONFIG_FPGA_DELAY 1188 1189 If defined, a function that provides delays in the FPGA 1190 configuration driver. 1191 1192 CFG_FPGA_CHECK_CTRLC 1193 Allow Control-C to interrupt FPGA configuration 1194 1195 CFG_FPGA_CHECK_ERROR 1196 1197 Check for configuration errors during FPGA bitfile 1198 loading. For example, abort during Virtex II 1199 configuration if the INIT_B line goes low (which 1200 indicated a CRC error). 1201 1202 CFG_FPGA_WAIT_INIT 1203 1204 Maximum time to wait for the INIT_B line to deassert 1205 after PROB_B has been deasserted during a Virtex II 1206 FPGA configuration sequence. The default time is 500 1207 mS. 1208 1209 CFG_FPGA_WAIT_BUSY 1210 1211 Maximum time to wait for BUSY to deassert during 1212 Virtex II FPGA configuration. The default is 5 mS. 1213 1214 CFG_FPGA_WAIT_CONFIG 1215 1216 Time to wait after FPGA configuration. The default is 1217 200 mS. 1218 1219- Configuration Management: 1220 CONFIG_IDENT_STRING 1221 1222 If defined, this string will be added to the U-Boot 1223 version information (U_BOOT_VERSION) 1224 1225- Vendor Parameter Protection: 1226 1227 U-Boot considers the values of the environment 1228 variables "serial#" (Board Serial Number) and 1229 "ethaddr" (Ethernet Address) to be parameters that 1230 are set once by the board vendor / manufacturer, and 1231 protects these variables from casual modification by 1232 the user. Once set, these variables are read-only, 1233 and write or delete attempts are rejected. You can 1234 change this behviour: 1235 1236 If CONFIG_ENV_OVERWRITE is #defined in your config 1237 file, the write protection for vendor parameters is 1238 completely disabled. Anybody can change or delete 1239 these parameters. 1240 1241 Alternatively, if you #define _both_ CONFIG_ETHADDR 1242 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 1243 ethernet address is installed in the environment, 1244 which can be changed exactly ONCE by the user. [The 1245 serial# is unaffected by this, i. e. it remains 1246 read-only.] 1247 1248- Protected RAM: 1249 CONFIG_PRAM 1250 1251 Define this variable to enable the reservation of 1252 "protected RAM", i. e. RAM which is not overwritten 1253 by U-Boot. Define CONFIG_PRAM to hold the number of 1254 kB you want to reserve for pRAM. You can overwrite 1255 this default value by defining an environment 1256 variable "pram" to the number of kB you want to 1257 reserve. Note that the board info structure will 1258 still show the full amount of RAM. If pRAM is 1259 reserved, a new environment variable "mem" will 1260 automatically be defined to hold the amount of 1261 remaining RAM in a form that can be passed as boot 1262 argument to Linux, for instance like that: 1263 1264 setenv bootargs ... mem=\$(mem) 1265 saveenv 1266 1267 This way you can tell Linux not to use this memory, 1268 either, which results in a memory region that will 1269 not be affected by reboots. 1270 1271 *WARNING* If your board configuration uses automatic 1272 detection of the RAM size, you must make sure that 1273 this memory test is non-destructive. So far, the 1274 following board configurations are known to be 1275 "pRAM-clean": 1276 1277 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL, 1278 HERMES, IP860, RPXlite, LWMON, LANTEC, 1279 PCU_E, FLAGADM, TQM8260 1280 1281- Error Recovery: 1282 CONFIG_PANIC_HANG 1283 1284 Define this variable to stop the system in case of a 1285 fatal error, so that you have to reset it manually. 1286 This is probably NOT a good idea for an embedded 1287 system where you want to system to reboot 1288 automatically as fast as possible, but it may be 1289 useful during development since you can try to debug 1290 the conditions that lead to the situation. 1291 1292 CONFIG_NET_RETRY_COUNT 1293 1294 This variable defines the number of retries for 1295 network operations like ARP, RARP, TFTP, or BOOTP 1296 before giving up the operation. If not defined, a 1297 default value of 5 is used. 1298 1299- Command Interpreter: 1300 CFG_HUSH_PARSER 1301 1302 Define this variable to enable the "hush" shell (from 1303 Busybox) as command line interpreter, thus enabling 1304 powerful command line syntax like 1305 if...then...else...fi conditionals or `&&' and '||' 1306 constructs ("shell scripts"). 1307 1308 If undefined, you get the old, much simpler behaviour 1309 with a somewhat smaller memory footprint. 1310 1311 1312 CFG_PROMPT_HUSH_PS2 1313 1314 This defines the secondary prompt string, which is 1315 printed when the command interpreter needs more input 1316 to complete a command. Usually "> ". 1317 1318 Note: 1319 1320 In the current implementation, the local variables 1321 space and global environment variables space are 1322 separated. Local variables are those you define by 1323 simply typing `name=value'. To access a local 1324 variable later on, you have write `$name' or 1325 `${name}'; to execute the contents of a variable 1326 directly type `$name' at the command prompt. 1327 1328 Global environment variables are those you use 1329 setenv/printenv to work with. To run a command stored 1330 in such a variable, you need to use the run command, 1331 and you must not use the '$' sign to access them. 1332 1333 To store commands and special characters in a 1334 variable, please use double quotation marks 1335 surrounding the whole text of the variable, instead 1336 of the backslashes before semicolons and special 1337 symbols. 1338 1339- Default Environment 1340 CONFIG_EXTRA_ENV_SETTINGS 1341 1342 Define this to contain any number of null terminated 1343 strings (variable = value pairs) that will be part of 1344 the default environment compiled into the boot image. 1345 1346 For example, place something like this in your 1347 board's config file: 1348 1349 #define CONFIG_EXTRA_ENV_SETTINGS \ 1350 "myvar1=value1\0" \ 1351 "myvar2=value2\0" 1352 1353 Warning: This method is based on knowledge about the 1354 internal format how the environment is stored by the 1355 U-Boot code. This is NOT an official, exported 1356 interface! Although it is unlikely that this format 1357 will change soon, there is no guarantee either. 1358 You better know what you are doing here. 1359 1360 Note: overly (ab)use of the default environment is 1361 discouraged. Make sure to check other ways to preset 1362 the environment like the autoscript function or the 1363 boot command first. 1364 1365- DataFlash Support 1366 CONFIG_HAS_DATAFLASH 1367 1368 Defining this option enables DataFlash features and 1369 allows to read/write in Dataflash via the standard 1370 commands cp, md... 1371 1372- Show boot progress 1373 CONFIG_SHOW_BOOT_PROGRESS 1374 1375 Defining this option allows to add some board- 1376 specific code (calling a user-provided function 1377 "show_boot_progress(int)") that enables you to show 1378 the system's boot progress on some display (for 1379 example, some LED's) on your board. At the moment, 1380 the following checkpoints are implemented: 1381 1382 Arg Where When 1383 1 common/cmd_bootm.c before attempting to boot an image 1384 -1 common/cmd_bootm.c Image header has bad magic number 1385 2 common/cmd_bootm.c Image header has correct magic number 1386 -2 common/cmd_bootm.c Image header has bad checksum 1387 3 common/cmd_bootm.c Image header has correct checksum 1388 -3 common/cmd_bootm.c Image data has bad checksum 1389 4 common/cmd_bootm.c Image data has correct checksum 1390 -4 common/cmd_bootm.c Image is for unsupported architecture 1391 5 common/cmd_bootm.c Architecture check OK 1392 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone) 1393 6 common/cmd_bootm.c Image Type check OK 1394 -6 common/cmd_bootm.c gunzip uncompression error 1395 -7 common/cmd_bootm.c Unimplemented compression type 1396 7 common/cmd_bootm.c Uncompression OK 1397 -8 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone) 1398 8 common/cmd_bootm.c Image Type check OK 1399 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 1400 9 common/cmd_bootm.c Start initial ramdisk verification 1401 -10 common/cmd_bootm.c Ramdisk header has bad magic number 1402 -11 common/cmd_bootm.c Ramdisk header has bad checksum 1403 10 common/cmd_bootm.c Ramdisk header is OK 1404 -12 common/cmd_bootm.c Ramdisk data has bad checksum 1405 11 common/cmd_bootm.c Ramdisk data has correct checksum 1406 12 common/cmd_bootm.c Ramdisk verification complete, start loading 1407 -13 common/cmd_bootm.c Wrong Image Type (not PPC Linux Ramdisk) 1408 13 common/cmd_bootm.c Start multifile image verification 1409 14 common/cmd_bootm.c No initial ramdisk, no multifile, continue. 1410 15 common/cmd_bootm.c All preparation done, transferring control to OS 1411 1412 -1 common/cmd_doc.c Bad usage of "doc" command 1413 -1 common/cmd_doc.c No boot device 1414 -1 common/cmd_doc.c Unknown Chip ID on boot device 1415 -1 common/cmd_doc.c Read Error on boot device 1416 -1 common/cmd_doc.c Image header has bad magic number 1417 1418 -1 common/cmd_ide.c Bad usage of "ide" command 1419 -1 common/cmd_ide.c No boot device 1420 -1 common/cmd_ide.c Unknown boot device 1421 -1 common/cmd_ide.c Unknown partition table 1422 -1 common/cmd_ide.c Invalid partition type 1423 -1 common/cmd_ide.c Read Error on boot device 1424 -1 common/cmd_ide.c Image header has bad magic number 1425 1426 -1 common/cmd_nand.c Bad usage of "nand" command 1427 -1 common/cmd_nand.c No boot device 1428 -1 common/cmd_nand.c Unknown Chip ID on boot device 1429 -1 common/cmd_nand.c Read Error on boot device 1430 -1 common/cmd_nand.c Image header has bad magic number 1431 1432 -1 common/env_common.c Environment has a bad CRC, using default 1433 1434 1435Modem Support: 1436-------------- 1437 1438[so far only for SMDK2400 and TRAB boards] 1439 1440- Modem support endable: 1441 CONFIG_MODEM_SUPPORT 1442 1443- RTS/CTS Flow control enable: 1444 CONFIG_HWFLOW 1445 1446- Modem debug support: 1447 CONFIG_MODEM_SUPPORT_DEBUG 1448 1449 Enables debugging stuff (char screen[1024], dbg()) 1450 for modem support. Useful only with BDI2000. 1451 1452- General: 1453 1454 In the target system modem support is enabled when a 1455 specific key (key combination) is pressed during 1456 power-on. Otherwise U-Boot will boot normally 1457 (autoboot). The key_pressed() fuction is called from 1458 board_init(). Currently key_pressed() is a dummy 1459 function, returning 1 and thus enabling modem 1460 initialization. 1461 1462 If there are no modem init strings in the 1463 environment, U-Boot proceed to autoboot; the 1464 previous output (banner, info printfs) will be 1465 supressed, though. 1466 1467 See also: doc/README.Modem 1468 1469 1470Configuration Settings: 1471----------------------- 1472 1473- CFG_LONGHELP: Defined when you want long help messages included; 1474 undefine this when you're short of memory. 1475 1476- CFG_PROMPT: This is what U-Boot prints on the console to 1477 prompt for user input. 1478 1479- CFG_CBSIZE: Buffer size for input from the Console 1480 1481- CFG_PBSIZE: Buffer size for Console output 1482 1483- CFG_MAXARGS: max. Number of arguments accepted for monitor commands 1484 1485- CFG_BARGSIZE: Buffer size for Boot Arguments which are passed to 1486 the application (usually a Linux kernel) when it is 1487 booted 1488 1489- CFG_BAUDRATE_TABLE: 1490 List of legal baudrate settings for this board. 1491 1492- CFG_CONSOLE_INFO_QUIET 1493 Suppress display of console information at boot. 1494 1495- CFG_CONSOLE_IS_IN_ENV 1496 If the board specific function 1497 extern int overwrite_console (void); 1498 returns 1, the stdin, stderr and stdout are switched to the 1499 serial port, else the settings in the environment are used. 1500 1501- CFG_CONSOLE_OVERWRITE_ROUTINE 1502 Enable the call to overwrite_console(). 1503 1504- CFG_CONSOLE_ENV_OVERWRITE 1505 Enable overwrite of previous console environment settings. 1506 1507- CFG_MEMTEST_START, CFG_MEMTEST_END: 1508 Begin and End addresses of the area used by the 1509 simple memory test. 1510 1511- CFG_ALT_MEMTEST: 1512 Enable an alternate, more extensive memory test. 1513 1514- CFG_MEMTEST_SCRATCH: 1515 Scratch address used by the alternate memory test 1516 You only need to set this if address zero isn't writeable 1517 1518- CFG_TFTP_LOADADDR: 1519 Default load address for network file downloads 1520 1521- CFG_LOADS_BAUD_CHANGE: 1522 Enable temporary baudrate change while serial download 1523 1524- CFG_SDRAM_BASE: 1525 Physical start address of SDRAM. _Must_ be 0 here. 1526 1527- CFG_MBIO_BASE: 1528 Physical start address of Motherboard I/O (if using a 1529 Cogent motherboard) 1530 1531- CFG_FLASH_BASE: 1532 Physical start address of Flash memory. 1533 1534- CFG_MONITOR_BASE: 1535 Physical start address of boot monitor code (set by 1536 make config files to be same as the text base address 1537 (TEXT_BASE) used when linking) - same as 1538 CFG_FLASH_BASE when booting from flash. 1539 1540- CFG_MONITOR_LEN: 1541 Size of memory reserved for monitor code, used to 1542 determine _at_compile_time_ (!) if the environment is 1543 embedded within the U-Boot image, or in a separate 1544 flash sector. 1545 1546- CFG_MALLOC_LEN: 1547 Size of DRAM reserved for malloc() use. 1548 1549- CFG_BOOTMAPSZ: 1550 Maximum size of memory mapped by the startup code of 1551 the Linux kernel; all data that must be processed by 1552 the Linux kernel (bd_info, boot arguments, eventually 1553 initrd image) must be put below this limit. 1554 1555- CFG_MAX_FLASH_BANKS: 1556 Max number of Flash memory banks 1557 1558- CFG_MAX_FLASH_SECT: 1559 Max number of sectors on a Flash chip 1560 1561- CFG_FLASH_ERASE_TOUT: 1562 Timeout for Flash erase operations (in ms) 1563 1564- CFG_FLASH_WRITE_TOUT: 1565 Timeout for Flash write operations (in ms) 1566 1567- CFG_FLASH_LOCK_TOUT 1568 Timeout for Flash set sector lock bit operation (in ms) 1569 1570- CFG_FLASH_UNLOCK_TOUT 1571 Timeout for Flash clear lock bits operation (in ms) 1572 1573- CFG_FLASH_PROTECTION 1574 If defined, hardware flash sectors protection is used 1575 instead of U-Boot software protection. 1576 1577- CFG_DIRECT_FLASH_TFTP: 1578 1579 Enable TFTP transfers directly to flash memory; 1580 without this option such a download has to be 1581 performed in two steps: (1) download to RAM, and (2) 1582 copy from RAM to flash. 1583 1584 The two-step approach is usually more reliable, since 1585 you can check if the download worked before you erase 1586 the flash, but in some situations (when sytem RAM is 1587 too limited to allow for a tempory copy of the 1588 downloaded image) this option may be very useful. 1589 1590- CFG_FLASH_CFI: 1591 Define if the flash driver uses extra elements in the 1592 common flash structure for storing flash geometry 1593 1594- CFG_RX_ETH_BUFFER: 1595 Defines the number of ethernet receive buffers. On some 1596 ethernet controllers it is recommended to set this value 1597 to 8 or even higher (EEPRO100 or 405 EMAC), since all 1598 buffers can be full shortly after enabling the interface 1599 on high ethernet traffic. 1600 Defaults to 4 if not defined. 1601 1602The following definitions that deal with the placement and management 1603of environment data (variable area); in general, we support the 1604following configurations: 1605 1606- CFG_ENV_IS_IN_FLASH: 1607 1608 Define this if the environment is in flash memory. 1609 1610 a) The environment occupies one whole flash sector, which is 1611 "embedded" in the text segment with the U-Boot code. This 1612 happens usually with "bottom boot sector" or "top boot 1613 sector" type flash chips, which have several smaller 1614 sectors at the start or the end. For instance, such a 1615 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In 1616 such a case you would place the environment in one of the 1617 4 kB sectors - with U-Boot code before and after it. With 1618 "top boot sector" type flash chips, you would put the 1619 environment in one of the last sectors, leaving a gap 1620 between U-Boot and the environment. 1621 1622 - CFG_ENV_OFFSET: 1623 1624 Offset of environment data (variable area) to the 1625 beginning of flash memory; for instance, with bottom boot 1626 type flash chips the second sector can be used: the offset 1627 for this sector is given here. 1628 1629 CFG_ENV_OFFSET is used relative to CFG_FLASH_BASE. 1630 1631 - CFG_ENV_ADDR: 1632 1633 This is just another way to specify the start address of 1634 the flash sector containing the environment (instead of 1635 CFG_ENV_OFFSET). 1636 1637 - CFG_ENV_SECT_SIZE: 1638 1639 Size of the sector containing the environment. 1640 1641 1642 b) Sometimes flash chips have few, equal sized, BIG sectors. 1643 In such a case you don't want to spend a whole sector for 1644 the environment. 1645 1646 - CFG_ENV_SIZE: 1647 1648 If you use this in combination with CFG_ENV_IS_IN_FLASH 1649 and CFG_ENV_SECT_SIZE, you can specify to use only a part 1650 of this flash sector for the environment. This saves 1651 memory for the RAM copy of the environment. 1652 1653 It may also save flash memory if you decide to use this 1654 when your environment is "embedded" within U-Boot code, 1655 since then the remainder of the flash sector could be used 1656 for U-Boot code. It should be pointed out that this is 1657 STRONGLY DISCOURAGED from a robustness point of view: 1658 updating the environment in flash makes it always 1659 necessary to erase the WHOLE sector. If something goes 1660 wrong before the contents has been restored from a copy in 1661 RAM, your target system will be dead. 1662 1663 - CFG_ENV_ADDR_REDUND 1664 CFG_ENV_SIZE_REDUND 1665 1666 These settings describe a second storage area used to hold 1667 a redundand copy of the environment data, so that there is 1668 a valid backup copy in case there is a power failure during 1669 a "saveenv" operation. 1670 1671BE CAREFUL! Any changes to the flash layout, and some changes to the 1672source code will make it necessary to adapt <board>/u-boot.lds* 1673accordingly! 1674 1675 1676- CFG_ENV_IS_IN_NVRAM: 1677 1678 Define this if you have some non-volatile memory device 1679 (NVRAM, battery buffered SRAM) which you want to use for the 1680 environment. 1681 1682 - CFG_ENV_ADDR: 1683 - CFG_ENV_SIZE: 1684 1685 These two #defines are used to determin the memory area you 1686 want to use for environment. It is assumed that this memory 1687 can just be read and written to, without any special 1688 provision. 1689 1690BE CAREFUL! The first access to the environment happens quite early 1691in U-Boot initalization (when we try to get the setting of for the 1692console baudrate). You *MUST* have mappend your NVRAM area then, or 1693U-Boot will hang. 1694 1695Please note that even with NVRAM we still use a copy of the 1696environment in RAM: we could work on NVRAM directly, but we want to 1697keep settings there always unmodified except somebody uses "saveenv" 1698to save the current settings. 1699 1700 1701- CFG_ENV_IS_IN_EEPROM: 1702 1703 Use this if you have an EEPROM or similar serial access 1704 device and a driver for it. 1705 1706 - CFG_ENV_OFFSET: 1707 - CFG_ENV_SIZE: 1708 1709 These two #defines specify the offset and size of the 1710 environment area within the total memory of your EEPROM. 1711 1712 - CFG_I2C_EEPROM_ADDR: 1713 If defined, specified the chip address of the EEPROM device. 1714 The default address is zero. 1715 1716 - CFG_EEPROM_PAGE_WRITE_BITS: 1717 If defined, the number of bits used to address bytes in a 1718 single page in the EEPROM device. A 64 byte page, for example 1719 would require six bits. 1720 1721 - CFG_EEPROM_PAGE_WRITE_DELAY_MS: 1722 If defined, the number of milliseconds to delay between 1723 page writes. The default is zero milliseconds. 1724 1725 - CFG_I2C_EEPROM_ADDR_LEN: 1726 The length in bytes of the EEPROM memory array address. Note 1727 that this is NOT the chip address length! 1728 1729 - CFG_EEPROM_SIZE: 1730 The size in bytes of the EEPROM device. 1731 1732 1733- CFG_SPI_INIT_OFFSET 1734 1735 Defines offset to the initial SPI buffer area in DPRAM. The 1736 area is used at an early stage (ROM part) if the environment 1737 is configured to reside in the SPI EEPROM: We need a 520 byte 1738 scratch DPRAM area. It is used between the two initialization 1739 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems 1740 to be a good choice since it makes it far enough from the 1741 start of the data area as well as from the stack pointer. 1742 1743Please note that the environment is read-only as long as the monitor 1744has been relocated to RAM and a RAM copy of the environment has been 1745created; also, when using EEPROM you will have to use getenv_r() 1746until then to read environment variables. 1747 1748The environment is protected by a CRC32 checksum. Before the monitor 1749is relocated into RAM, as a result of a bad CRC you will be working 1750with the compiled-in default environment - *silently*!!! [This is 1751necessary, because the first environment variable we need is the 1752"baudrate" setting for the console - if we have a bad CRC, we don't 1753have any device yet where we could complain.] 1754 1755Note: once the monitor has been relocated, then it will complain if 1756the default environment is used; a new CRC is computed as soon as you 1757use the "saveenv" command to store a valid environment. 1758 1759- CFG_FAULT_ECHO_LINK_DOWN: 1760 Echo the inverted Ethernet link state to the fault LED. 1761 1762 Note: If this option is active, then CFG_FAULT_MII_ADDR 1763 also needs to be defined. 1764 1765- CFG_FAULT_MII_ADDR: 1766 MII address of the PHY to check for the Ethernet link state. 1767 1768Low Level (hardware related) configuration options: 1769--------------------------------------------------- 1770 1771- CFG_CACHELINE_SIZE: 1772 Cache Line Size of the CPU. 1773 1774- CFG_DEFAULT_IMMR: 1775 Default address of the IMMR after system reset. 1776 1777 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU, 1778 and RPXsuper) to be able to adjust the position of 1779 the IMMR register after a reset. 1780 1781- Floppy Disk Support: 1782 CFG_FDC_DRIVE_NUMBER 1783 1784 the default drive number (default value 0) 1785 1786 CFG_ISA_IO_STRIDE 1787 1788 defines the spacing between fdc chipset registers 1789 (default value 1) 1790 1791 CFG_ISA_IO_OFFSET 1792 1793 defines the offset of register from address. It 1794 depends on which part of the data bus is connected to 1795 the fdc chipset. (default value 0) 1796 1797 If CFG_ISA_IO_STRIDE CFG_ISA_IO_OFFSET and 1798 CFG_FDC_DRIVE_NUMBER are undefined, they take their 1799 default value. 1800 1801 if CFG_FDC_HW_INIT is defined, then the function 1802 fdc_hw_init() is called at the beginning of the FDC 1803 setup. fdc_hw_init() must be provided by the board 1804 source code. It is used to make hardware dependant 1805 initializations. 1806 1807- CFG_IMMR: Physical address of the Internal Memory Mapped 1808 Register; DO NOT CHANGE! (11-4) 1809 [MPC8xx systems only] 1810 1811- CFG_INIT_RAM_ADDR: 1812 1813 Start address of memory area that can be used for 1814 initial data and stack; please note that this must be 1815 writable memory that is working WITHOUT special 1816 initialization, i. e. you CANNOT use normal RAM which 1817 will become available only after programming the 1818 memory controller and running certain initialization 1819 sequences. 1820 1821 U-Boot uses the following memory types: 1822 - MPC8xx and MPC8260: IMMR (internal memory of the CPU) 1823 - MPC824X: data cache 1824 - PPC4xx: data cache 1825 1826- CFG_GBL_DATA_OFFSET: 1827 1828 Offset of the initial data structure in the memory 1829 area defined by CFG_INIT_RAM_ADDR. Usually 1830 CFG_GBL_DATA_OFFSET is chosen such that the initial 1831 data is located at the end of the available space 1832 (sometimes written as (CFG_INIT_RAM_END - 1833 CFG_INIT_DATA_SIZE), and the initial stack is just 1834 below that area (growing from (CFG_INIT_RAM_ADDR + 1835 CFG_GBL_DATA_OFFSET) downward. 1836 1837 Note: 1838 On the MPC824X (or other systems that use the data 1839 cache for initial memory) the address chosen for 1840 CFG_INIT_RAM_ADDR is basically arbitrary - it must 1841 point to an otherwise UNUSED address space between 1842 the top of RAM and the start of the PCI space. 1843 1844- CFG_SIUMCR: SIU Module Configuration (11-6) 1845 1846- CFG_SYPCR: System Protection Control (11-9) 1847 1848- CFG_TBSCR: Time Base Status and Control (11-26) 1849 1850- CFG_PISCR: Periodic Interrupt Status and Control (11-31) 1851 1852- CFG_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30) 1853 1854- CFG_SCCR: System Clock and reset Control Register (15-27) 1855 1856- CFG_OR_TIMING_SDRAM: 1857 SDRAM timing 1858 1859- CFG_MAMR_PTA: 1860 periodic timer for refresh 1861 1862- CFG_DER: Debug Event Register (37-47) 1863 1864- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CFG_REMAP_OR_AM, 1865 CFG_PRELIM_OR_AM, CFG_OR_TIMING_FLASH, CFG_OR0_REMAP, 1866 CFG_OR0_PRELIM, CFG_BR0_PRELIM, CFG_OR1_REMAP, CFG_OR1_PRELIM, 1867 CFG_BR1_PRELIM: 1868 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 1869 1870- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 1871 CFG_OR_TIMING_SDRAM, CFG_OR2_PRELIM, CFG_BR2_PRELIM, 1872 CFG_OR3_PRELIM, CFG_BR3_PRELIM: 1873 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 1874 1875- CFG_MAMR_PTA, CFG_MPTPR_2BK_4K, CFG_MPTPR_1BK_4K, CFG_MPTPR_2BK_8K, 1876 CFG_MPTPR_1BK_8K, CFG_MAMR_8COL, CFG_MAMR_9COL: 1877 Machine Mode Register and Memory Periodic Timer 1878 Prescaler definitions (SDRAM timing) 1879 1880- CFG_I2C_UCODE_PATCH, CFG_I2C_DPMEM_OFFSET [0x1FC0]: 1881 enable I2C microcode relocation patch (MPC8xx); 1882 define relocation offset in DPRAM [DSP2] 1883 1884- CFG_SPI_UCODE_PATCH, CFG_SPI_DPMEM_OFFSET [0x1FC0]: 1885 enable SPI microcode relocation patch (MPC8xx); 1886 define relocation offset in DPRAM [SCC4] 1887 1888- CFG_USE_OSCCLK: 1889 Use OSCM clock mode on MBX8xx board. Be careful, 1890 wrong setting might damage your board. Read 1891 doc/README.MBX before setting this variable! 1892 1893- CFG_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only) 1894 Offset of the bootmode word in DPRAM used by post 1895 (Power On Self Tests). This definition overrides 1896 #define'd default value in commproc.h resp. 1897 cpm_8260.h. 1898 1899- CFG_PCI_SLV_MEM_LOCAL, CFG_PCI_SLV_MEM_BUS, CFG_PICMR0_MASK_ATTRIB, 1900 CFG_PCI_MSTR0_LOCAL, CFG_PCIMSK0_MASK, CFG_PCI_MSTR1_LOCAL, 1901 CFG_PCIMSK1_MASK, CFG_PCI_MSTR_MEM_LOCAL, CFG_PCI_MSTR_MEM_BUS, 1902 CFG_CPU_PCI_MEM_START, CFG_PCI_MSTR_MEM_SIZE, CFG_POCMR0_MASK_ATTRIB, 1903 CFG_PCI_MSTR_MEMIO_LOCAL, CFG_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START, 1904 CFG_PCI_MSTR_MEMIO_SIZE, CFG_POCMR1_MASK_ATTRIB, CFG_PCI_MSTR_IO_LOCAL, 1905 CFG_PCI_MSTR_IO_BUS, CFG_CPU_PCI_IO_START, CFG_PCI_MSTR_IO_SIZE, 1906 CFG_POCMR2_MASK_ATTRIB: (MPC826x only) 1907 Overrides the default PCI memory map in cpu/mpc8260/pci.c if set. 1908 1909Building the Software: 1910====================== 1911 1912Building U-Boot has been tested in native PPC environments (on a 1913PowerBook G3 running LinuxPPC 2000) and in cross environments 1914(running RedHat 6.x and 7.x Linux on x86, Solaris 2.6 on a SPARC, and 1915NetBSD 1.5 on x86). 1916 1917If you are not using a native PPC environment, it is assumed that you 1918have the GNU cross compiling tools available in your path and named 1919with a prefix of "powerpc-linux-". If this is not the case, (e.g. if 1920you are using Monta Vista's Hard Hat Linux CDK 1.2) you must change 1921the definition of CROSS_COMPILE in Makefile. For HHL on a 4xx CPU, 1922change it to: 1923 1924 CROSS_COMPILE = ppc_4xx- 1925 1926 1927U-Boot is intended to be simple to build. After installing the 1928sources you must configure U-Boot for one specific board type. This 1929is done by typing: 1930 1931 make NAME_config 1932 1933where "NAME_config" is the name of one of the existing 1934configurations; the following names are supported: 1935 1936 ADCIOP_config GTH_config TQM850L_config 1937 ADS860_config IP860_config TQM855L_config 1938 AR405_config IVML24_config TQM860L_config 1939 CANBT_config IVMS8_config WALNUT405_config 1940 CPCI405_config LANTEC_config cogent_common_config 1941 CPCIISER4_config MBX_config cogent_mpc8260_config 1942 CU824_config MBX860T_config cogent_mpc8xx_config 1943 ESTEEM192E_config RPXlite_config hermes_config 1944 ETX094_config RPXsuper_config hymod_config 1945 FADS823_config SM850_config lwmon_config 1946 FADS850SAR_config SPD823TS_config pcu_e_config 1947 FADS860T_config SXNI855T_config rsdproto_config 1948 FPS850L_config Sandpoint8240_config sbc8260_config 1949 GENIETV_config TQM823L_config PIP405_config 1950 GEN860T_config EBONY_config FPS860L_config 1951 ELPT860_config cmi_mpc5xx_config NETVIA_config 1952 at91rm9200dk_config omap1510inn_config MPC8260ADS_config 1953 omap1610inn_config ZPC1900_config 1954 1955Note: for some board special configuration names may exist; check if 1956 additional information is available from the board vendor; for 1957 instance, the TQM8xxL systems run normally at 50 MHz and use a 1958 SCC for 10baseT ethernet; there are also systems with 80 MHz 1959 CPU clock, and an optional Fast Ethernet module is available 1960 for CPU's with FEC. You can select such additional "features" 1961 when chosing the configuration, i. e. 1962 1963 make TQM860L_config 1964 - will configure for a plain TQM860L, i. e. 50MHz, no FEC 1965 1966 make TQM860L_FEC_config 1967 - will configure for a TQM860L at 50MHz with FEC for ethernet 1968 1969 make TQM860L_80MHz_config 1970 - will configure for a TQM860L at 80 MHz, with normal 10baseT 1971 interface 1972 1973 make TQM860L_FEC_80MHz_config 1974 - will configure for a TQM860L at 80 MHz with FEC for ethernet 1975 1976 make TQM823L_LCD_config 1977 - will configure for a TQM823L with U-Boot console on LCD 1978 1979 make TQM823L_LCD_80MHz_config 1980 - will configure for a TQM823L at 80 MHz with U-Boot console on LCD 1981 1982 etc. 1983 1984 1985Finally, type "make all", and you should get some working U-Boot 1986images ready for download to / installation on your system: 1987 1988- "u-boot.bin" is a raw binary image 1989- "u-boot" is an image in ELF binary format 1990- "u-boot.srec" is in Motorola S-Record format 1991 1992 1993Please be aware that the Makefiles assume you are using GNU make, so 1994for instance on NetBSD you might need to use "gmake" instead of 1995native "make". 1996 1997 1998If the system board that you have is not listed, then you will need 1999to port U-Boot to your hardware platform. To do this, follow these 2000steps: 2001 20021. Add a new configuration option for your board to the toplevel 2003 "Makefile" and to the "MAKEALL" script, using the existing 2004 entries as examples. Note that here and at many other places 2005 boards and other names are listed in alphabetical sort order. Please 2006 keep this order. 20072. Create a new directory to hold your board specific code. Add any 2008 files you need. In your board directory, you will need at least 2009 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds". 20103. Create a new configuration file "include/configs/<board>.h" for 2011 your board 20123. If you're porting U-Boot to a new CPU, then also create a new 2013 directory to hold your CPU specific code. Add any files you need. 20144. Run "make <board>_config" with your new name. 20155. Type "make", and you should get a working "u-boot.srec" file 2016 to be installed on your target system. 20176. Debug and solve any problems that might arise. 2018 [Of course, this last step is much harder than it sounds.] 2019 2020 2021Testing of U-Boot Modifications, Ports to New Hardware, etc.: 2022============================================================== 2023 2024If you have modified U-Boot sources (for instance added a new board 2025or support for new devices, a new CPU, etc.) you are expected to 2026provide feedback to the other developers. The feedback normally takes 2027the form of a "patch", i. e. a context diff against a certain (latest 2028official or latest in CVS) version of U-Boot sources. 2029 2030But before you submit such a patch, please verify that your modifi- 2031cation did not break existing code. At least make sure that *ALL* of 2032the supported boards compile WITHOUT ANY compiler warnings. To do so, 2033just run the "MAKEALL" script, which will configure and build U-Boot 2034for ALL supported system. Be warned, this will take a while. You can 2035select which (cross) compiler to use by passing a `CROSS_COMPILE' 2036environment variable to the script, i. e. to use the cross tools from 2037MontaVista's Hard Hat Linux you can type 2038 2039 CROSS_COMPILE=ppc_8xx- MAKEALL 2040 2041or to build on a native PowerPC system you can type 2042 2043 CROSS_COMPILE=' ' MAKEALL 2044 2045See also "U-Boot Porting Guide" below. 2046 2047 2048Monitor Commands - Overview: 2049============================ 2050 2051go - start application at address 'addr' 2052run - run commands in an environment variable 2053bootm - boot application image from memory 2054bootp - boot image via network using BootP/TFTP protocol 2055tftpboot- boot image via network using TFTP protocol 2056 and env variables "ipaddr" and "serverip" 2057 (and eventually "gatewayip") 2058rarpboot- boot image via network using RARP/TFTP protocol 2059diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 2060loads - load S-Record file over serial line 2061loadb - load binary file over serial line (kermit mode) 2062md - memory display 2063mm - memory modify (auto-incrementing) 2064nm - memory modify (constant address) 2065mw - memory write (fill) 2066cp - memory copy 2067cmp - memory compare 2068crc32 - checksum calculation 2069imd - i2c memory display 2070imm - i2c memory modify (auto-incrementing) 2071inm - i2c memory modify (constant address) 2072imw - i2c memory write (fill) 2073icrc32 - i2c checksum calculation 2074iprobe - probe to discover valid I2C chip addresses 2075iloop - infinite loop on address range 2076isdram - print SDRAM configuration information 2077sspi - SPI utility commands 2078base - print or set address offset 2079printenv- print environment variables 2080setenv - set environment variables 2081saveenv - save environment variables to persistent storage 2082protect - enable or disable FLASH write protection 2083erase - erase FLASH memory 2084flinfo - print FLASH memory information 2085bdinfo - print Board Info structure 2086iminfo - print header information for application image 2087coninfo - print console devices and informations 2088ide - IDE sub-system 2089loop - infinite loop on address range 2090mtest - simple RAM test 2091icache - enable or disable instruction cache 2092dcache - enable or disable data cache 2093reset - Perform RESET of the CPU 2094echo - echo args to console 2095version - print monitor version 2096help - print online help 2097? - alias for 'help' 2098 2099 2100Monitor Commands - Detailed Description: 2101======================================== 2102 2103TODO. 2104 2105For now: just type "help <command>". 2106 2107 2108Environment Variables: 2109====================== 2110 2111U-Boot supports user configuration using Environment Variables which 2112can be made persistent by saving to Flash memory. 2113 2114Environment Variables are set using "setenv", printed using 2115"printenv", and saved to Flash using "saveenv". Using "setenv" 2116without a value can be used to delete a variable from the 2117environment. As long as you don't save the environment you are 2118working with an in-memory copy. In case the Flash area containing the 2119environment is erased by accident, a default environment is provided. 2120 2121Some configuration options can be set using Environment Variables: 2122 2123 baudrate - see CONFIG_BAUDRATE 2124 2125 bootdelay - see CONFIG_BOOTDELAY 2126 2127 bootcmd - see CONFIG_BOOTCOMMAND 2128 2129 bootargs - Boot arguments when booting an RTOS image 2130 2131 bootfile - Name of the image to load with TFTP 2132 2133 autoload - if set to "no" (any string beginning with 'n'), 2134 "bootp" will just load perform a lookup of the 2135 configuration from the BOOTP server, but not try to 2136 load any image using TFTP 2137 2138 autostart - if set to "yes", an image loaded using the "bootp", 2139 "rarpboot", "tftpboot" or "diskboot" commands will 2140 be automatically started (by internally calling 2141 "bootm") 2142 2143 If set to "no", a standalone image passed to the 2144 "bootm" command will be copied to the load address 2145 (and eventually uncompressed), but NOT be started. 2146 This can be used to load and uncompress arbitrary 2147 data. 2148 2149 initrd_high - restrict positioning of initrd images: 2150 If this variable is not set, initrd images will be 2151 copied to the highest possible address in RAM; this 2152 is usually what you want since it allows for 2153 maximum initrd size. If for some reason you want to 2154 make sure that the initrd image is loaded below the 2155 CFG_BOOTMAPSZ limit, you can set this environment 2156 variable to a value of "no" or "off" or "0". 2157 Alternatively, you can set it to a maximum upper 2158 address to use (U-Boot will still check that it 2159 does not overwrite the U-Boot stack and data). 2160 2161 For instance, when you have a system with 16 MB 2162 RAM, and want to reserve 4 MB from use by Linux, 2163 you can do this by adding "mem=12M" to the value of 2164 the "bootargs" variable. However, now you must make 2165 sure that the initrd image is placed in the first 2166 12 MB as well - this can be done with 2167 2168 setenv initrd_high 00c00000 2169 2170 If you set initrd_high to 0xFFFFFFFF, this is an 2171 indication to U-Boot that all addresses are legal 2172 for the Linux kernel, including addresses in flash 2173 memory. In this case U-Boot will NOT COPY the 2174 ramdisk at all. This may be useful to reduce the 2175 boot time on your system, but requires that this 2176 feature is supported by your Linux kernel. 2177 2178 ipaddr - IP address; needed for tftpboot command 2179 2180 loadaddr - Default load address for commands like "bootp", 2181 "rarpboot", "tftpboot", "loadb" or "diskboot" 2182 2183 loads_echo - see CONFIG_LOADS_ECHO 2184 2185 serverip - TFTP server IP address; needed for tftpboot command 2186 2187 bootretry - see CONFIG_BOOT_RETRY_TIME 2188 2189 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 2190 2191 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 2192 2193 2194The following environment variables may be used and automatically 2195updated by the network boot commands ("bootp" and "rarpboot"), 2196depending the information provided by your boot server: 2197 2198 bootfile - see above 2199 dnsip - IP address of your Domain Name Server 2200 dnsip2 - IP address of your secondary Domain Name Server 2201 gatewayip - IP address of the Gateway (Router) to use 2202 hostname - Target hostname 2203 ipaddr - see above 2204 netmask - Subnet Mask 2205 rootpath - Pathname of the root filesystem on the NFS server 2206 serverip - see above 2207 2208 2209There are two special Environment Variables: 2210 2211 serial# - contains hardware identification information such 2212 as type string and/or serial number 2213 ethaddr - Ethernet address 2214 2215These variables can be set only once (usually during manufacturing of 2216the board). U-Boot refuses to delete or overwrite these variables 2217once they have been set once. 2218 2219 2220Further special Environment Variables: 2221 2222 ver - Contains the U-Boot version string as printed 2223 with the "version" command. This variable is 2224 readonly (see CONFIG_VERSION_VARIABLE). 2225 2226 2227Please note that changes to some configuration parameters may take 2228only effect after the next boot (yes, that's just like Windoze :-). 2229 2230 2231Command Line Parsing: 2232===================== 2233 2234There are two different command line parsers available with U-Boot: 2235the old "simple" one, and the much more powerful "hush" shell: 2236 2237Old, simple command line parser: 2238-------------------------------- 2239 2240- supports environment variables (through setenv / saveenv commands) 2241- several commands on one line, separated by ';' 2242- variable substitution using "... $(name) ..." syntax 2243- special characters ('$', ';') can be escaped by prefixing with '\', 2244 for example: 2245 setenv bootcmd bootm \$(address) 2246- You can also escape text by enclosing in single apostrophes, for example: 2247 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off' 2248 2249Hush shell: 2250----------- 2251 2252- similar to Bourne shell, with control structures like 2253 if...then...else...fi, for...do...done; while...do...done, 2254 until...do...done, ... 2255- supports environment ("global") variables (through setenv / saveenv 2256 commands) and local shell variables (through standard shell syntax 2257 "name=value"); only environment variables can be used with "run" 2258 command 2259 2260General rules: 2261-------------- 2262 2263(1) If a command line (or an environment variable executed by a "run" 2264 command) contains several commands separated by semicolon, and 2265 one of these commands fails, then the remaining commands will be 2266 executed anyway. 2267 2268(2) If you execute several variables with one call to run (i. e. 2269 calling run with a list af variables as arguments), any failing 2270 command will cause "run" to terminate, i. e. the remaining 2271 variables are not executed. 2272 2273Note for Redundant Ethernet Interfaces: 2274======================================= 2275 2276Some boards come with redundant ethernet interfaces; U-Boot supports 2277such configurations and is capable of automatic selection of a 2278"working" interface when needed. MAC assignment works as follows: 2279 2280Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 2281MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 2282"eth1addr" (=>eth1), "eth2addr", ... 2283 2284If the network interface stores some valid MAC address (for instance 2285in SROM), this is used as default address if there is NO correspon- 2286ding setting in the environment; if the corresponding environment 2287variable is set, this overrides the settings in the card; that means: 2288 2289o If the SROM has a valid MAC address, and there is no address in the 2290 environment, the SROM's address is used. 2291 2292o If there is no valid address in the SROM, and a definition in the 2293 environment exists, then the value from the environment variable is 2294 used. 2295 2296o If both the SROM and the environment contain a MAC address, and 2297 both addresses are the same, this MAC address is used. 2298 2299o If both the SROM and the environment contain a MAC address, and the 2300 addresses differ, the value from the environment is used and a 2301 warning is printed. 2302 2303o If neither SROM nor the environment contain a MAC address, an error 2304 is raised. 2305 2306 2307Image Formats: 2308============== 2309 2310The "boot" commands of this monitor operate on "image" files which 2311can be basicly anything, preceeded by a special header; see the 2312definitions in include/image.h for details; basicly, the header 2313defines the following image properties: 2314 2315* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 2316 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 2317 LynxOS, pSOS, QNX, RTEMS, ARTOS; 2318 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, ARTOS, LynxOS). 2319* Target CPU Architecture (Provisions for Alpha, ARM, Intel x86, 2320 IA64, MIPS, MIPS, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 2321 Currently supported: PowerPC). 2322* Compression Type (uncompressed, gzip, bzip2) 2323* Load Address 2324* Entry Point 2325* Image Name 2326* Image Timestamp 2327 2328The header is marked by a special Magic Number, and both the header 2329and the data portions of the image are secured against corruption by 2330CRC32 checksums. 2331 2332 2333Linux Support: 2334============== 2335 2336Although U-Boot should support any OS or standalone application 2337easily, the main focus has always been on Linux during the design of 2338U-Boot. 2339 2340U-Boot includes many features that so far have been part of some 2341special "boot loader" code within the Linux kernel. Also, any 2342"initrd" images to be used are no longer part of one big Linux image; 2343instead, kernel and "initrd" are separate images. This implementation 2344serves several purposes: 2345 2346- the same features can be used for other OS or standalone 2347 applications (for instance: using compressed images to reduce the 2348 Flash memory footprint) 2349 2350- it becomes much easier to port new Linux kernel versions because 2351 lots of low-level, hardware dependent stuff are done by U-Boot 2352 2353- the same Linux kernel image can now be used with different "initrd" 2354 images; of course this also means that different kernel images can 2355 be run with the same "initrd". This makes testing easier (you don't 2356 have to build a new "zImage.initrd" Linux image when you just 2357 change a file in your "initrd"). Also, a field-upgrade of the 2358 software is easier now. 2359 2360 2361Linux HOWTO: 2362============ 2363 2364Porting Linux to U-Boot based systems: 2365--------------------------------------- 2366 2367U-Boot cannot save you from doing all the necessary modifications to 2368configure the Linux device drivers for use with your target hardware 2369(no, we don't intend to provide a full virtual machine interface to 2370Linux :-). 2371 2372But now you can ignore ALL boot loader code (in arch/ppc/mbxboot). 2373 2374Just make sure your machine specific header file (for instance 2375include/asm-ppc/tqm8xx.h) includes the same definition of the Board 2376Information structure as we define in include/u-boot.h, and make 2377sure that your definition of IMAP_ADDR uses the same value as your 2378U-Boot configuration in CFG_IMMR. 2379 2380 2381Configuring the Linux kernel: 2382----------------------------- 2383 2384No specific requirements for U-Boot. Make sure you have some root 2385device (initial ramdisk, NFS) for your target system. 2386 2387 2388Building a Linux Image: 2389----------------------- 2390 2391With U-Boot, "normal" build targets like "zImage" or "bzImage" are 2392not used. If you use recent kernel source, a new build target 2393"uImage" will exist which automatically builds an image usable by 2394U-Boot. Most older kernels also have support for a "pImage" target, 2395which was introduced for our predecessor project PPCBoot and uses a 2396100% compatible format. 2397 2398Example: 2399 2400 make TQM850L_config 2401 make oldconfig 2402 make dep 2403 make uImage 2404 2405The "uImage" build target uses a special tool (in 'tools/mkimage') to 2406encapsulate a compressed Linux kernel image with header information, 2407CRC32 checksum etc. for use with U-Boot. This is what we are doing: 2408 2409* build a standard "vmlinux" kernel image (in ELF binary format): 2410 2411* convert the kernel into a raw binary image: 2412 2413 ${CROSS_COMPILE}-objcopy -O binary \ 2414 -R .note -R .comment \ 2415 -S vmlinux linux.bin 2416 2417* compress the binary image: 2418 2419 gzip -9 linux.bin 2420 2421* package compressed binary image for U-Boot: 2422 2423 mkimage -A ppc -O linux -T kernel -C gzip \ 2424 -a 0 -e 0 -n "Linux Kernel Image" \ 2425 -d linux.bin.gz uImage 2426 2427 2428The "mkimage" tool can also be used to create ramdisk images for use 2429with U-Boot, either separated from the Linux kernel image, or 2430combined into one file. "mkimage" encapsulates the images with a 64 2431byte header containing information about target architecture, 2432operating system, image type, compression method, entry points, time 2433stamp, CRC32 checksums, etc. 2434 2435"mkimage" can be called in two ways: to verify existing images and 2436print the header information, or to build new images. 2437 2438In the first form (with "-l" option) mkimage lists the information 2439contained in the header of an existing U-Boot image; this includes 2440checksum verification: 2441 2442 tools/mkimage -l image 2443 -l ==> list image header information 2444 2445The second form (with "-d" option) is used to build a U-Boot image 2446from a "data file" which is used as image payload: 2447 2448 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 2449 -n name -d data_file image 2450 -A ==> set architecture to 'arch' 2451 -O ==> set operating system to 'os' 2452 -T ==> set image type to 'type' 2453 -C ==> set compression type 'comp' 2454 -a ==> set load address to 'addr' (hex) 2455 -e ==> set entry point to 'ep' (hex) 2456 -n ==> set image name to 'name' 2457 -d ==> use image data from 'datafile' 2458 2459Right now, all Linux kernels use the same load address (0x00000000), 2460but the entry point address depends on the kernel version: 2461 2462- 2.2.x kernels have the entry point at 0x0000000C, 2463- 2.3.x and later kernels have the entry point at 0x00000000. 2464 2465So a typical call to build a U-Boot image would read: 2466 2467 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 2468 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 2469 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz \ 2470 > examples/uImage.TQM850L 2471 Image Name: 2.4.4 kernel for TQM850L 2472 Created: Wed Jul 19 02:34:59 2000 2473 Image Type: PowerPC Linux Kernel Image (gzip compressed) 2474 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 2475 Load Address: 0x00000000 2476 Entry Point: 0x00000000 2477 2478To verify the contents of the image (or check for corruption): 2479 2480 -> tools/mkimage -l examples/uImage.TQM850L 2481 Image Name: 2.4.4 kernel for TQM850L 2482 Created: Wed Jul 19 02:34:59 2000 2483 Image Type: PowerPC Linux Kernel Image (gzip compressed) 2484 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 2485 Load Address: 0x00000000 2486 Entry Point: 0x00000000 2487 2488NOTE: for embedded systems where boot time is critical you can trade 2489speed for memory and install an UNCOMPRESSED image instead: this 2490needs more space in Flash, but boots much faster since it does not 2491need to be uncompressed: 2492 2493 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz 2494 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 2495 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 2496 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux \ 2497 > examples/uImage.TQM850L-uncompressed 2498 Image Name: 2.4.4 kernel for TQM850L 2499 Created: Wed Jul 19 02:34:59 2000 2500 Image Type: PowerPC Linux Kernel Image (uncompressed) 2501 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 2502 Load Address: 0x00000000 2503 Entry Point: 0x00000000 2504 2505 2506Similar you can build U-Boot images from a 'ramdisk.image.gz' file 2507when your kernel is intended to use an initial ramdisk: 2508 2509 -> tools/mkimage -n 'Simple Ramdisk Image' \ 2510 > -A ppc -O linux -T ramdisk -C gzip \ 2511 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 2512 Image Name: Simple Ramdisk Image 2513 Created: Wed Jan 12 14:01:50 2000 2514 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 2515 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 2516 Load Address: 0x00000000 2517 Entry Point: 0x00000000 2518 2519 2520Installing a Linux Image: 2521------------------------- 2522 2523To downloading a U-Boot image over the serial (console) interface, 2524you must convert the image to S-Record format: 2525 2526 objcopy -I binary -O srec examples/image examples/image.srec 2527 2528The 'objcopy' does not understand the information in the U-Boot 2529image header, so the resulting S-Record file will be relative to 2530address 0x00000000. To load it to a given address, you need to 2531specify the target address as 'offset' parameter with the 'loads' 2532command. 2533 2534Example: install the image to address 0x40100000 (which on the 2535TQM8xxL is in the first Flash bank): 2536 2537 => erase 40100000 401FFFFF 2538 2539 .......... done 2540 Erased 8 sectors 2541 2542 => loads 40100000 2543 ## Ready for S-Record download ... 2544 ~>examples/image.srec 2545 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 2546 ... 2547 15989 15990 15991 15992 2548 [file transfer complete] 2549 [connected] 2550 ## Start Addr = 0x00000000 2551 2552 2553You can check the success of the download using the 'iminfo' command; 2554this includes a checksum verification so you can be sure no data 2555corruption happened: 2556 2557 => imi 40100000 2558 2559 ## Checking Image at 40100000 ... 2560 Image Name: 2.2.13 for initrd on TQM850L 2561 Image Type: PowerPC Linux Kernel Image (gzip compressed) 2562 Data Size: 335725 Bytes = 327 kB = 0 MB 2563 Load Address: 00000000 2564 Entry Point: 0000000c 2565 Verifying Checksum ... OK 2566 2567 2568Boot Linux: 2569----------- 2570 2571The "bootm" command is used to boot an application that is stored in 2572memory (RAM or Flash). In case of a Linux kernel image, the contents 2573of the "bootargs" environment variable is passed to the kernel as 2574parameters. You can check and modify this variable using the 2575"printenv" and "setenv" commands: 2576 2577 2578 => printenv bootargs 2579 bootargs=root=/dev/ram 2580 2581 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 2582 2583 => printenv bootargs 2584 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 2585 2586 => bootm 40020000 2587 ## Booting Linux kernel at 40020000 ... 2588 Image Name: 2.2.13 for NFS on TQM850L 2589 Image Type: PowerPC Linux Kernel Image (gzip compressed) 2590 Data Size: 381681 Bytes = 372 kB = 0 MB 2591 Load Address: 00000000 2592 Entry Point: 0000000c 2593 Verifying Checksum ... OK 2594 Uncompressing Kernel Image ... OK 2595 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 2596 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 2597 time_init: decrementer frequency = 187500000/60 2598 Calibrating delay loop... 49.77 BogoMIPS 2599 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 2600 ... 2601 2602If you want to boot a Linux kernel with initial ram disk, you pass 2603the memory addresses of both the kernel and the initrd image (PPBCOOT 2604format!) to the "bootm" command: 2605 2606 => imi 40100000 40200000 2607 2608 ## Checking Image at 40100000 ... 2609 Image Name: 2.2.13 for initrd on TQM850L 2610 Image Type: PowerPC Linux Kernel Image (gzip compressed) 2611 Data Size: 335725 Bytes = 327 kB = 0 MB 2612 Load Address: 00000000 2613 Entry Point: 0000000c 2614 Verifying Checksum ... OK 2615 2616 ## Checking Image at 40200000 ... 2617 Image Name: Simple Ramdisk Image 2618 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 2619 Data Size: 566530 Bytes = 553 kB = 0 MB 2620 Load Address: 00000000 2621 Entry Point: 00000000 2622 Verifying Checksum ... OK 2623 2624 => bootm 40100000 40200000 2625 ## Booting Linux kernel at 40100000 ... 2626 Image Name: 2.2.13 for initrd on TQM850L 2627 Image Type: PowerPC Linux Kernel Image (gzip compressed) 2628 Data Size: 335725 Bytes = 327 kB = 0 MB 2629 Load Address: 00000000 2630 Entry Point: 0000000c 2631 Verifying Checksum ... OK 2632 Uncompressing Kernel Image ... OK 2633 ## Loading RAMDisk Image at 40200000 ... 2634 Image Name: Simple Ramdisk Image 2635 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 2636 Data Size: 566530 Bytes = 553 kB = 0 MB 2637 Load Address: 00000000 2638 Entry Point: 00000000 2639 Verifying Checksum ... OK 2640 Loading Ramdisk ... OK 2641 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 2642 Boot arguments: root=/dev/ram 2643 time_init: decrementer frequency = 187500000/60 2644 Calibrating delay loop... 49.77 BogoMIPS 2645 ... 2646 RAMDISK: Compressed image found at block 0 2647 VFS: Mounted root (ext2 filesystem). 2648 2649 bash# 2650 2651More About U-Boot Image Types: 2652------------------------------ 2653 2654U-Boot supports the following image types: 2655 2656 "Standalone Programs" are directly runnable in the environment 2657 provided by U-Boot; it is expected that (if they behave 2658 well) you can continue to work in U-Boot after return from 2659 the Standalone Program. 2660 "OS Kernel Images" are usually images of some Embedded OS which 2661 will take over control completely. Usually these programs 2662 will install their own set of exception handlers, device 2663 drivers, set up the MMU, etc. - this means, that you cannot 2664 expect to re-enter U-Boot except by resetting the CPU. 2665 "RAMDisk Images" are more or less just data blocks, and their 2666 parameters (address, size) are passed to an OS kernel that is 2667 being started. 2668 "Multi-File Images" contain several images, typically an OS 2669 (Linux) kernel image and one or more data images like 2670 RAMDisks. This construct is useful for instance when you want 2671 to boot over the network using BOOTP etc., where the boot 2672 server provides just a single image file, but you want to get 2673 for instance an OS kernel and a RAMDisk image. 2674 2675 "Multi-File Images" start with a list of image sizes, each 2676 image size (in bytes) specified by an "uint32_t" in network 2677 byte order. This list is terminated by an "(uint32_t)0". 2678 Immediately after the terminating 0 follow the images, one by 2679 one, all aligned on "uint32_t" boundaries (size rounded up to 2680 a multiple of 4 bytes). 2681 2682 "Firmware Images" are binary images containing firmware (like 2683 U-Boot or FPGA images) which usually will be programmed to 2684 flash memory. 2685 2686 "Script files" are command sequences that will be executed by 2687 U-Boot's command interpreter; this feature is especially 2688 useful when you configure U-Boot to use a real shell (hush) 2689 as command interpreter. 2690 2691 2692Standalone HOWTO: 2693================= 2694 2695One of the features of U-Boot is that you can dynamically load and 2696run "standalone" applications, which can use some resources of 2697U-Boot like console I/O functions or interrupt services. 2698 2699Two simple examples are included with the sources: 2700 2701"Hello World" Demo: 2702------------------- 2703 2704'examples/hello_world.c' contains a small "Hello World" Demo 2705application; it is automatically compiled when you build U-Boot. 2706It's configured to run at address 0x00040004, so you can play with it 2707like that: 2708 2709 => loads 2710 ## Ready for S-Record download ... 2711 ~>examples/hello_world.srec 2712 1 2 3 4 5 6 7 8 9 10 11 ... 2713 [file transfer complete] 2714 [connected] 2715 ## Start Addr = 0x00040004 2716 2717 => go 40004 Hello World! This is a test. 2718 ## Starting application at 0x00040004 ... 2719 Hello World 2720 argc = 7 2721 argv[0] = "40004" 2722 argv[1] = "Hello" 2723 argv[2] = "World!" 2724 argv[3] = "This" 2725 argv[4] = "is" 2726 argv[5] = "a" 2727 argv[6] = "test." 2728 argv[7] = "<NULL>" 2729 Hit any key to exit ... 2730 2731 ## Application terminated, rc = 0x0 2732 2733Another example, which demonstrates how to register a CPM interrupt 2734handler with the U-Boot code, can be found in 'examples/timer.c'. 2735Here, a CPM timer is set up to generate an interrupt every second. 2736The interrupt service routine is trivial, just printing a '.' 2737character, but this is just a demo program. The application can be 2738controlled by the following keys: 2739 2740 ? - print current values og the CPM Timer registers 2741 b - enable interrupts and start timer 2742 e - stop timer and disable interrupts 2743 q - quit application 2744 2745 => loads 2746 ## Ready for S-Record download ... 2747 ~>examples/timer.srec 2748 1 2 3 4 5 6 7 8 9 10 11 ... 2749 [file transfer complete] 2750 [connected] 2751 ## Start Addr = 0x00040004 2752 2753 => go 40004 2754 ## Starting application at 0x00040004 ... 2755 TIMERS=0xfff00980 2756 Using timer 1 2757 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 2758 2759Hit 'b': 2760 [q, b, e, ?] Set interval 1000000 us 2761 Enabling timer 2762Hit '?': 2763 [q, b, e, ?] ........ 2764 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 2765Hit '?': 2766 [q, b, e, ?] . 2767 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 2768Hit '?': 2769 [q, b, e, ?] . 2770 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 2771Hit '?': 2772 [q, b, e, ?] . 2773 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 2774Hit 'e': 2775 [q, b, e, ?] ...Stopping timer 2776Hit 'q': 2777 [q, b, e, ?] ## Application terminated, rc = 0x0 2778 2779 2780Minicom warning: 2781================ 2782 2783Over time, many people have reported problems when trying to use the 2784"minicom" terminal emulation program for serial download. I (wd) 2785consider minicom to be broken, and recommend not to use it. Under 2786Unix, I recommend to use C-Kermit for general purpose use (and 2787especially for kermit binary protocol download ("loadb" command), and 2788use "cu" for S-Record download ("loads" command). 2789 2790Nevertheless, if you absolutely want to use it try adding this 2791configuration to your "File transfer protocols" section: 2792 2793 Name Program Name U/D FullScr IO-Red. Multi 2794 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N 2795 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N 2796 2797 2798NetBSD Notes: 2799============= 2800 2801Starting at version 0.9.2, U-Boot supports NetBSD both as host 2802(build U-Boot) and target system (boots NetBSD/mpc8xx). 2803 2804Building requires a cross environment; it is known to work on 2805NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 2806need gmake since the Makefiles are not compatible with BSD make). 2807Note that the cross-powerpc package does not install include files; 2808attempting to build U-Boot will fail because <machine/ansi.h> is 2809missing. This file has to be installed and patched manually: 2810 2811 # cd /usr/pkg/cross/powerpc-netbsd/include 2812 # mkdir powerpc 2813 # ln -s powerpc machine 2814 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 2815 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 2816 2817Native builds *don't* work due to incompatibilities between native 2818and U-Boot include files. 2819 2820Booting assumes that (the first part of) the image booted is a 2821stage-2 loader which in turn loads and then invokes the kernel 2822proper. Loader sources will eventually appear in the NetBSD source 2823tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 2824meantime, send mail to bruno@exet-ag.de and/or wd@denx.de for 2825details. 2826 2827 2828Implementation Internals: 2829========================= 2830 2831The following is not intended to be a complete description of every 2832implementation detail. However, it should help to understand the 2833inner workings of U-Boot and make it easier to port it to custom 2834hardware. 2835 2836 2837Initial Stack, Global Data: 2838--------------------------- 2839 2840The implementation of U-Boot is complicated by the fact that U-Boot 2841starts running out of ROM (flash memory), usually without access to 2842system RAM (because the memory controller is not initialized yet). 2843This means that we don't have writable Data or BSS segments, and BSS 2844is not initialized as zero. To be able to get a C environment working 2845at all, we have to allocate at least a minimal stack. Implementation 2846options for this are defined and restricted by the CPU used: Some CPU 2847models provide on-chip memory (like the IMMR area on MPC8xx and 2848MPC826x processors), on others (parts of) the data cache can be 2849locked as (mis-) used as memory, etc. 2850 2851 Chris Hallinan posted a good summary of these issues to the 2852 u-boot-users mailing list: 2853 2854 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 2855 From: "Chris Hallinan" <clh@net1plus.com> 2856 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 2857 ... 2858 2859 Correct me if I'm wrong, folks, but the way I understand it 2860 is this: Using DCACHE as initial RAM for Stack, etc, does not 2861 require any physical RAM backing up the cache. The cleverness 2862 is that the cache is being used as a temporary supply of 2863 necessary storage before the SDRAM controller is setup. It's 2864 beyond the scope of this list to expain the details, but you 2865 can see how this works by studying the cache architecture and 2866 operation in the architecture and processor-specific manuals. 2867 2868 OCM is On Chip Memory, which I believe the 405GP has 4K. It 2869 is another option for the system designer to use as an 2870 initial stack/ram area prior to SDRAM being available. Either 2871 option should work for you. Using CS 4 should be fine if your 2872 board designers haven't used it for something that would 2873 cause you grief during the initial boot! It is frequently not 2874 used. 2875 2876 CFG_INIT_RAM_ADDR should be somewhere that won't interfere 2877 with your processor/board/system design. The default value 2878 you will find in any recent u-boot distribution in 2879 Walnut405.h should work for you. I'd set it to a value larger 2880 than your SDRAM module. If you have a 64MB SDRAM module, set 2881 it above 400_0000. Just make sure your board has no resources 2882 that are supposed to respond to that address! That code in 2883 start.S has been around a while and should work as is when 2884 you get the config right. 2885 2886 -Chris Hallinan 2887 DS4.COM, Inc. 2888 2889It is essential to remember this, since it has some impact on the C 2890code for the initialization procedures: 2891 2892* Initialized global data (data segment) is read-only. Do not attempt 2893 to write it. 2894 2895* Do not use any unitialized global data (or implicitely initialized 2896 as zero data - BSS segment) at all - this is undefined, initiali- 2897 zation is performed later (when relocating to RAM). 2898 2899* Stack space is very limited. Avoid big data buffers or things like 2900 that. 2901 2902Having only the stack as writable memory limits means we cannot use 2903normal global data to share information beween the code. But it 2904turned out that the implementation of U-Boot can be greatly 2905simplified by making a global data structure (gd_t) available to all 2906functions. We could pass a pointer to this data as argument to _all_ 2907functions, but this would bloat the code. Instead we use a feature of 2908the GCC compiler (Global Register Variables) to share the data: we 2909place a pointer (gd) to the global data into a register which we 2910reserve for this purpose. 2911 2912When choosing a register for such a purpose we are restricted by the 2913relevant (E)ABI specifications for the current architecture, and by 2914GCC's implementation. 2915 2916For PowerPC, the following registers have specific use: 2917 R1: stack pointer 2918 R2: TOC pointer 2919 R3-R4: parameter passing and return values 2920 R5-R10: parameter passing 2921 R13: small data area pointer 2922 R30: GOT pointer 2923 R31: frame pointer 2924 2925 (U-Boot also uses R14 as internal GOT pointer.) 2926 2927 ==> U-Boot will use R29 to hold a pointer to the global data 2928 2929 Note: on PPC, we could use a static initializer (since the 2930 address of the global data structure is known at compile time), 2931 but it turned out that reserving a register results in somewhat 2932 smaller code - although the code savings are not that big (on 2933 average for all boards 752 bytes for the whole U-Boot image, 2934 624 text + 127 data). 2935 2936On ARM, the following registers are used: 2937 2938 R0: function argument word/integer result 2939 R1-R3: function argument word 2940 R9: GOT pointer 2941 R10: stack limit (used only if stack checking if enabled) 2942 R11: argument (frame) pointer 2943 R12: temporary workspace 2944 R13: stack pointer 2945 R14: link register 2946 R15: program counter 2947 2948 ==> U-Boot will use R8 to hold a pointer to the global data 2949 2950 2951Memory Management: 2952------------------ 2953 2954U-Boot runs in system state and uses physical addresses, i.e. the 2955MMU is not used either for address mapping nor for memory protection. 2956 2957The available memory is mapped to fixed addresses using the memory 2958controller. In this process, a contiguous block is formed for each 2959memory type (Flash, SDRAM, SRAM), even when it consists of several 2960physical memory banks. 2961 2962U-Boot is installed in the first 128 kB of the first Flash bank (on 2963TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 2964booting and sizing and initializing DRAM, the code relocates itself 2965to the upper end of DRAM. Immediately below the U-Boot code some 2966memory is reserved for use by malloc() [see CFG_MALLOC_LEN 2967configuration setting]. Below that, a structure with global Board 2968Info data is placed, followed by the stack (growing downward). 2969 2970Additionally, some exception handler code is copied to the low 8 kB 2971of DRAM (0x00000000 ... 0x00001FFF). 2972 2973So a typical memory configuration with 16 MB of DRAM could look like 2974this: 2975 2976 0x0000 0000 Exception Vector code 2977 : 2978 0x0000 1FFF 2979 0x0000 2000 Free for Application Use 2980 : 2981 : 2982 2983 : 2984 : 2985 0x00FB FF20 Monitor Stack (Growing downward) 2986 0x00FB FFAC Board Info Data and permanent copy of global data 2987 0x00FC 0000 Malloc Arena 2988 : 2989 0x00FD FFFF 2990 0x00FE 0000 RAM Copy of Monitor Code 2991 ... eventually: LCD or video framebuffer 2992 ... eventually: pRAM (Protected RAM - unchanged by reset) 2993 0x00FF FFFF [End of RAM] 2994 2995 2996System Initialization: 2997---------------------- 2998 2999In the reset configuration, U-Boot starts at the reset entry point 3000(on most PowerPC systens at address 0x00000100). Because of the reset 3001configuration for CS0# this is a mirror of the onboard Flash memory. 3002To be able to re-map memory U-Boot then jumps to its link address. 3003To be able to implement the initialization code in C, a (small!) 3004initial stack is set up in the internal Dual Ported RAM (in case CPUs 3005which provide such a feature like MPC8xx or MPC8260), or in a locked 3006part of the data cache. After that, U-Boot initializes the CPU core, 3007the caches and the SIU. 3008 3009Next, all (potentially) available memory banks are mapped using a 3010preliminary mapping. For example, we put them on 512 MB boundaries 3011(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 3012on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 3013programmed for SDRAM access. Using the temporary configuration, a 3014simple memory test is run that determines the size of the SDRAM 3015banks. 3016 3017When there is more than one SDRAM bank, and the banks are of 3018different size, the largest is mapped first. For equal size, the first 3019bank (CS2#) is mapped first. The first mapping is always for address 30200x00000000, with any additional banks following immediately to create 3021contiguous memory starting from 0. 3022 3023Then, the monitor installs itself at the upper end of the SDRAM area 3024and allocates memory for use by malloc() and for the global Board 3025Info data; also, the exception vector code is copied to the low RAM 3026pages, and the final stack is set up. 3027 3028Only after this relocation will you have a "normal" C environment; 3029until that you are restricted in several ways, mostly because you are 3030running from ROM, and because the code will have to be relocated to a 3031new address in RAM. 3032 3033 3034U-Boot Porting Guide: 3035---------------------- 3036 3037[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 3038list, October 2002] 3039 3040 3041int main (int argc, char *argv[]) 3042{ 3043 sighandler_t no_more_time; 3044 3045 signal (SIGALRM, no_more_time); 3046 alarm (PROJECT_DEADLINE - toSec (3 * WEEK)); 3047 3048 if (available_money > available_manpower) { 3049 pay consultant to port U-Boot; 3050 return 0; 3051 } 3052 3053 Download latest U-Boot source; 3054 3055 Subscribe to u-boot-users mailing list; 3056 3057 if (clueless) { 3058 email ("Hi, I am new to U-Boot, how do I get started?"); 3059 } 3060 3061 while (learning) { 3062 Read the README file in the top level directory; 3063 Read http://www.denx.de/re/DPLG.html 3064 Read the source, Luke; 3065 } 3066 3067 if (available_money > toLocalCurrency ($2500)) { 3068 Buy a BDI2000; 3069 } else { 3070 Add a lot of aggravation and time; 3071 } 3072 3073 Create your own board support subdirectory; 3074 3075 Create your own board config file; 3076 3077 while (!running) { 3078 do { 3079 Add / modify source code; 3080 } until (compiles); 3081 Debug; 3082 if (clueless) 3083 email ("Hi, I am having problems..."); 3084 } 3085 Send patch file to Wolfgang; 3086 3087 return 0; 3088} 3089 3090void no_more_time (int sig) 3091{ 3092 hire_a_guru(); 3093} 3094 3095 3096Coding Standards: 3097----------------- 3098 3099All contributions to U-Boot should conform to the Linux kernel 3100coding style; see the file "Documentation/CodingStyle" in your Linux 3101kernel source directory. 3102 3103Please note that U-Boot is implemented in C (and to some small parts 3104in Assembler); no C++ is used, so please do not use C++ style 3105comments (//) in your code. 3106 3107Submissions which do not conform to the standards may be returned 3108with a request to reformat the changes. 3109 3110 3111Submitting Patches: 3112------------------- 3113 3114Since the number of patches for U-Boot is growing, we need to 3115establish some rules. Submissions which do not conform to these rules 3116may be rejected, even when they contain important and valuable stuff. 3117 3118 3119When you send a patch, please include the following information with 3120it: 3121 3122* For bug fixes: a description of the bug and how your patch fixes 3123 this bug. Please try to include a way of demonstrating that the 3124 patch actually fixes something. 3125 3126* For new features: a description of the feature and your 3127 implementation. 3128 3129* A CHANGELOG entry as plaintext (separate from the patch) 3130 3131* For major contributions, your entry to the CREDITS file 3132 3133* When you add support for a new board, don't forget to add this 3134 board to the MAKEALL script, too. 3135 3136* If your patch adds new configuration options, don't forget to 3137 document these in the README file. 3138 3139* The patch itself. If you are accessing the CVS repository use "cvs 3140 update; cvs diff -puRN"; else, use "diff -purN OLD NEW". If your 3141 version of diff does not support these options, then get the latest 3142 version of GNU diff. 3143 3144 The current directory when running this command shall be the top 3145 level directory of the U-Boot source tree, or it's parent directory 3146 (i. e. please make sure that your patch includes sufficient 3147 directory information for the affected files). 3148 3149 We accept patches as plain text, MIME attachments or as uuencoded 3150 gzipped text. 3151 3152* If one logical set of modifications affects or creates several 3153 files, all these changes shall be submitted in a SINGLE patch file. 3154 3155* Changesets that contain different, unrelated modifications shall be 3156 submitted as SEPARATE patches, one patch per changeset. 3157 3158 3159Notes: 3160 3161* Before sending the patch, run the MAKEALL script on your patched 3162 source tree and make sure that no errors or warnings are reported 3163 for any of the boards. 3164 3165* Keep your modifications to the necessary minimum: A patch 3166 containing several unrelated changes or arbitrary reformats will be 3167 returned with a request to re-formatting / split it. 3168 3169* If you modify existing code, make sure that your new code does not 3170 add to the memory footprint of the code ;-) Small is beautiful! 3171 When adding new features, these should compile conditionally only 3172 (using #ifdef), and the resulting code with the new feature 3173 disabled must not need more memory than the old code without your 3174 modification. 3175