1# 2# (C) Copyright 2000 - 2012 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, ARM, MIPS and several other 29processors, which can be installed in a boot ROM and used to 30initialize and test the hardware or to download and run application 31code. 32 33The development of U-Boot is closely related to Linux: some parts of 34the source code originate in the Linux source tree, we have some 35header files in common, and special provision has been made to 36support booting of Linux images. 37 38Some attention has been paid to make this software easily 39configurable and extendable. For instance, all monitor commands are 40implemented with the same call interface, so that it's very easy to 41add new commands. Also, instead of permanently adding rarely used 42code (for instance hardware test utilities) to the monitor, you can 43load and run it dynamically. 44 45 46Status: 47======= 48 49In general, all boards for which a configuration option exists in the 50Makefile have been tested to some extent and can be considered 51"working". In fact, many of them are used in production systems. 52 53In case of problems see the CHANGELOG and CREDITS files to find out 54who contributed the specific port. The MAINTAINERS file lists board 55maintainers. 56 57 58Where to get help: 59================== 60 61In case you have questions about, problems with or contributions for 62U-Boot you should send a message to the U-Boot mailing list at 63<u-boot@lists.denx.de>. There is also an archive of previous traffic 64on the mailing list - please search the archive before asking FAQ's. 65Please see http://lists.denx.de/pipermail/u-boot and 66http://dir.gmane.org/gmane.comp.boot-loaders.u-boot 67 68 69Where to get source code: 70========================= 71 72The U-Boot source code is maintained in the git repository at 73git://www.denx.de/git/u-boot.git ; you can browse it online at 74http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary 75 76The "snapshot" links on this page allow you to download tarballs of 77any version you might be interested in. Official releases are also 78available for FTP download from the ftp://ftp.denx.de/pub/u-boot/ 79directory. 80 81Pre-built (and tested) images are available from 82ftp://ftp.denx.de/pub/u-boot/images/ 83 84 85Where we come from: 86=================== 87 88- start from 8xxrom sources 89- create PPCBoot project (http://sourceforge.net/projects/ppcboot) 90- clean up code 91- make it easier to add custom boards 92- make it possible to add other [PowerPC] CPUs 93- extend functions, especially: 94 * Provide extended interface to Linux boot loader 95 * S-Record download 96 * network boot 97 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot 98- create ARMBoot project (http://sourceforge.net/projects/armboot) 99- add other CPU families (starting with ARM) 100- create U-Boot project (http://sourceforge.net/projects/u-boot) 101- current project page: see http://www.denx.de/wiki/U-Boot 102 103 104Names and Spelling: 105=================== 106 107The "official" name of this project is "Das U-Boot". The spelling 108"U-Boot" shall be used in all written text (documentation, comments 109in source files etc.). Example: 110 111 This is the README file for the U-Boot project. 112 113File names etc. shall be based on the string "u-boot". Examples: 114 115 include/asm-ppc/u-boot.h 116 117 #include <asm/u-boot.h> 118 119Variable names, preprocessor constants etc. shall be either based on 120the string "u_boot" or on "U_BOOT". Example: 121 122 U_BOOT_VERSION u_boot_logo 123 IH_OS_U_BOOT u_boot_hush_start 124 125 126Versioning: 127=========== 128 129Starting with the release in October 2008, the names of the releases 130were changed from numerical release numbers without deeper meaning 131into a time stamp based numbering. Regular releases are identified by 132names consisting of the calendar year and month of the release date. 133Additional fields (if present) indicate release candidates or bug fix 134releases in "stable" maintenance trees. 135 136Examples: 137 U-Boot v2009.11 - Release November 2009 138 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree 139 U-Boot v2010.09-rc1 - Release candiate 1 for September 2010 release 140 141 142Directory Hierarchy: 143==================== 144 145/arch Architecture specific files 146 /arm Files generic to ARM architecture 147 /cpu CPU specific files 148 /arm720t Files specific to ARM 720 CPUs 149 /arm920t Files specific to ARM 920 CPUs 150 /at91 Files specific to Atmel AT91RM9200 CPU 151 /imx Files specific to Freescale MC9328 i.MX CPUs 152 /s3c24x0 Files specific to Samsung S3C24X0 CPUs 153 /arm925t Files specific to ARM 925 CPUs 154 /arm926ejs Files specific to ARM 926 CPUs 155 /arm1136 Files specific to ARM 1136 CPUs 156 /ixp Files specific to Intel XScale IXP CPUs 157 /pxa Files specific to Intel XScale PXA CPUs 158 /s3c44b0 Files specific to Samsung S3C44B0 CPUs 159 /sa1100 Files specific to Intel StrongARM SA1100 CPUs 160 /lib Architecture specific library files 161 /avr32 Files generic to AVR32 architecture 162 /cpu CPU specific files 163 /lib Architecture specific library files 164 /blackfin Files generic to Analog Devices Blackfin architecture 165 /cpu CPU specific files 166 /lib Architecture specific library files 167 /x86 Files generic to x86 architecture 168 /cpu CPU specific files 169 /lib Architecture specific library files 170 /m68k Files generic to m68k architecture 171 /cpu CPU specific files 172 /mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs 173 /mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs 174 /mcf532x Files specific to Freescale ColdFire MCF5329 CPUs 175 /mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs 176 /mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs 177 /lib Architecture specific library files 178 /microblaze Files generic to microblaze architecture 179 /cpu CPU specific files 180 /lib Architecture specific library files 181 /mips Files generic to MIPS architecture 182 /cpu CPU specific files 183 /mips32 Files specific to MIPS32 CPUs 184 /xburst Files specific to Ingenic XBurst CPUs 185 /lib Architecture specific library files 186 /nds32 Files generic to NDS32 architecture 187 /cpu CPU specific files 188 /n1213 Files specific to Andes Technology N1213 CPUs 189 /lib Architecture specific library files 190 /nios2 Files generic to Altera NIOS2 architecture 191 /cpu CPU specific files 192 /lib Architecture specific library files 193 /powerpc Files generic to PowerPC architecture 194 /cpu CPU specific files 195 /74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs 196 /mpc5xx Files specific to Freescale MPC5xx CPUs 197 /mpc5xxx Files specific to Freescale MPC5xxx CPUs 198 /mpc8xx Files specific to Freescale MPC8xx CPUs 199 /mpc8220 Files specific to Freescale MPC8220 CPUs 200 /mpc824x Files specific to Freescale MPC824x CPUs 201 /mpc8260 Files specific to Freescale MPC8260 CPUs 202 /mpc85xx Files specific to Freescale MPC85xx CPUs 203 /ppc4xx Files specific to AMCC PowerPC 4xx CPUs 204 /lib Architecture specific library files 205 /sh Files generic to SH architecture 206 /cpu CPU specific files 207 /sh2 Files specific to sh2 CPUs 208 /sh3 Files specific to sh3 CPUs 209 /sh4 Files specific to sh4 CPUs 210 /lib Architecture specific library files 211 /sparc Files generic to SPARC architecture 212 /cpu CPU specific files 213 /leon2 Files specific to Gaisler LEON2 SPARC CPU 214 /leon3 Files specific to Gaisler LEON3 SPARC CPU 215 /lib Architecture specific library files 216/api Machine/arch independent API for external apps 217/board Board dependent files 218/common Misc architecture independent functions 219/disk Code for disk drive partition handling 220/doc Documentation (don't expect too much) 221/drivers Commonly used device drivers 222/examples Example code for standalone applications, etc. 223/fs Filesystem code (cramfs, ext2, jffs2, etc.) 224/include Header Files 225/lib Files generic to all architectures 226 /libfdt Library files to support flattened device trees 227 /lzma Library files to support LZMA decompression 228 /lzo Library files to support LZO decompression 229/net Networking code 230/post Power On Self Test 231/rtc Real Time Clock drivers 232/tools Tools to build S-Record or U-Boot images, etc. 233 234Software Configuration: 235======================= 236 237Configuration is usually done using C preprocessor defines; the 238rationale behind that is to avoid dead code whenever possible. 239 240There are two classes of configuration variables: 241 242* Configuration _OPTIONS_: 243 These are selectable by the user and have names beginning with 244 "CONFIG_". 245 246* Configuration _SETTINGS_: 247 These depend on the hardware etc. and should not be meddled with if 248 you don't know what you're doing; they have names beginning with 249 "CONFIG_SYS_". 250 251Later we will add a configuration tool - probably similar to or even 252identical to what's used for the Linux kernel. Right now, we have to 253do the configuration by hand, which means creating some symbolic 254links and editing some configuration files. We use the TQM8xxL boards 255as an example here. 256 257 258Selection of Processor Architecture and Board Type: 259--------------------------------------------------- 260 261For all supported boards there are ready-to-use default 262configurations available; just type "make <board_name>_config". 263 264Example: For a TQM823L module type: 265 266 cd u-boot 267 make TQM823L_config 268 269For the Cogent platform, you need to specify the CPU type as well; 270e.g. "make cogent_mpc8xx_config". And also configure the cogent 271directory according to the instructions in cogent/README. 272 273 274Configuration Options: 275---------------------- 276 277Configuration depends on the combination of board and CPU type; all 278such information is kept in a configuration file 279"include/configs/<board_name>.h". 280 281Example: For a TQM823L module, all configuration settings are in 282"include/configs/TQM823L.h". 283 284 285Many of the options are named exactly as the corresponding Linux 286kernel configuration options. The intention is to make it easier to 287build a config tool - later. 288 289 290The following options need to be configured: 291 292- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX. 293 294- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS. 295 296- CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined) 297 Define exactly one, e.g. CONFIG_ATSTK1002 298 299- CPU Module Type: (if CONFIG_COGENT is defined) 300 Define exactly one of 301 CONFIG_CMA286_60_OLD 302--- FIXME --- not tested yet: 303 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P, 304 CONFIG_CMA287_23, CONFIG_CMA287_50 305 306- Motherboard Type: (if CONFIG_COGENT is defined) 307 Define exactly one of 308 CONFIG_CMA101, CONFIG_CMA102 309 310- Motherboard I/O Modules: (if CONFIG_COGENT is defined) 311 Define one or more of 312 CONFIG_CMA302 313 314- Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined) 315 Define one or more of 316 CONFIG_LCD_HEARTBEAT - update a character position on 317 the LCD display every second with 318 a "rotator" |\-/|\-/ 319 320- Board flavour: (if CONFIG_MPC8260ADS is defined) 321 CONFIG_ADSTYPE 322 Possible values are: 323 CONFIG_SYS_8260ADS - original MPC8260ADS 324 CONFIG_SYS_8266ADS - MPC8266ADS 325 CONFIG_SYS_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR 326 CONFIG_SYS_8272ADS - MPC8272ADS 327 328- Marvell Family Member 329 CONFIG_SYS_MVFS - define it if you want to enable 330 multiple fs option at one time 331 for marvell soc family 332 333- MPC824X Family Member (if CONFIG_MPC824X is defined) 334 Define exactly one of 335 CONFIG_MPC8240, CONFIG_MPC8245 336 337- 8xx CPU Options: (if using an MPC8xx CPU) 338 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if 339 get_gclk_freq() cannot work 340 e.g. if there is no 32KHz 341 reference PIT/RTC clock 342 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK 343 or XTAL/EXTAL) 344 345- 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU): 346 CONFIG_SYS_8xx_CPUCLK_MIN 347 CONFIG_SYS_8xx_CPUCLK_MAX 348 CONFIG_8xx_CPUCLK_DEFAULT 349 See doc/README.MPC866 350 351 CONFIG_SYS_MEASURE_CPUCLK 352 353 Define this to measure the actual CPU clock instead 354 of relying on the correctness of the configured 355 values. Mostly useful for board bringup to make sure 356 the PLL is locked at the intended frequency. Note 357 that this requires a (stable) reference clock (32 kHz 358 RTC clock or CONFIG_SYS_8XX_XIN) 359 360 CONFIG_SYS_DELAYED_ICACHE 361 362 Define this option if you want to enable the 363 ICache only when Code runs from RAM. 364 365- 85xx CPU Options: 366 CONFIG_SYS_FSL_TBCLK_DIV 367 368 Defines the core time base clock divider ratio compared to the 369 system clock. On most PQ3 devices this is 8, on newer QorIQ 370 devices it can be 16 or 32. The ratio varies from SoC to Soc. 371 372 CONFIG_SYS_FSL_PCIE_COMPAT 373 374 Defines the string to utilize when trying to match PCIe device 375 tree nodes for the given platform. 376 377- Intel Monahans options: 378 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO 379 380 Defines the Monahans run mode to oscillator 381 ratio. Valid values are 8, 16, 24, 31. The core 382 frequency is this value multiplied by 13 MHz. 383 384 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO 385 386 Defines the Monahans turbo mode to oscillator 387 ratio. Valid values are 1 (default if undefined) and 388 2. The core frequency as calculated above is multiplied 389 by this value. 390 391- MIPS CPU options: 392 CONFIG_SYS_INIT_SP_OFFSET 393 394 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack 395 pointer. This is needed for the temporary stack before 396 relocation. 397 398 CONFIG_SYS_MIPS_CACHE_MODE 399 400 Cache operation mode for the MIPS CPU. 401 See also arch/mips/include/asm/mipsregs.h. 402 Possible values are: 403 CONF_CM_CACHABLE_NO_WA 404 CONF_CM_CACHABLE_WA 405 CONF_CM_UNCACHED 406 CONF_CM_CACHABLE_NONCOHERENT 407 CONF_CM_CACHABLE_CE 408 CONF_CM_CACHABLE_COW 409 CONF_CM_CACHABLE_CUW 410 CONF_CM_CACHABLE_ACCELERATED 411 412 CONFIG_SYS_XWAY_EBU_BOOTCFG 413 414 Special option for Lantiq XWAY SoCs for booting from NOR flash. 415 See also arch/mips/cpu/mips32/start.S. 416 417 CONFIG_XWAY_SWAP_BYTES 418 419 Enable compilation of tools/xway-swap-bytes needed for Lantiq 420 XWAY SoCs for booting from NOR flash. The U-Boot image needs to 421 be swapped if a flash programmer is used. 422 423- ARM options: 424 CONFIG_SYS_EXCEPTION_VECTORS_HIGH 425 426 Select high exception vectors of the ARM core, e.g., do not 427 clear the V bit of the c1 register of CP15. 428 429- Linux Kernel Interface: 430 CONFIG_CLOCKS_IN_MHZ 431 432 U-Boot stores all clock information in Hz 433 internally. For binary compatibility with older Linux 434 kernels (which expect the clocks passed in the 435 bd_info data to be in MHz) the environment variable 436 "clocks_in_mhz" can be defined so that U-Boot 437 converts clock data to MHZ before passing it to the 438 Linux kernel. 439 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of 440 "clocks_in_mhz=1" is automatically included in the 441 default environment. 442 443 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only] 444 445 When transferring memsize parameter to linux, some versions 446 expect it to be in bytes, others in MB. 447 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes. 448 449 CONFIG_OF_LIBFDT 450 451 New kernel versions are expecting firmware settings to be 452 passed using flattened device trees (based on open firmware 453 concepts). 454 455 CONFIG_OF_LIBFDT 456 * New libfdt-based support 457 * Adds the "fdt" command 458 * The bootm command automatically updates the fdt 459 460 OF_CPU - The proper name of the cpus node (only required for 461 MPC512X and MPC5xxx based boards). 462 OF_SOC - The proper name of the soc node (only required for 463 MPC512X and MPC5xxx based boards). 464 OF_TBCLK - The timebase frequency. 465 OF_STDOUT_PATH - The path to the console device 466 467 boards with QUICC Engines require OF_QE to set UCC MAC 468 addresses 469 470 CONFIG_OF_BOARD_SETUP 471 472 Board code has addition modification that it wants to make 473 to the flat device tree before handing it off to the kernel 474 475 CONFIG_OF_BOOT_CPU 476 477 This define fills in the correct boot CPU in the boot 478 param header, the default value is zero if undefined. 479 480 CONFIG_OF_IDE_FIXUP 481 482 U-Boot can detect if an IDE device is present or not. 483 If not, and this new config option is activated, U-Boot 484 removes the ATA node from the DTS before booting Linux, 485 so the Linux IDE driver does not probe the device and 486 crash. This is needed for buggy hardware (uc101) where 487 no pull down resistor is connected to the signal IDE5V_DD7. 488 489 CONFIG_MACH_TYPE [relevant for ARM only][mandatory] 490 491 This setting is mandatory for all boards that have only one 492 machine type and must be used to specify the machine type 493 number as it appears in the ARM machine registry 494 (see http://www.arm.linux.org.uk/developer/machines/). 495 Only boards that have multiple machine types supported 496 in a single configuration file and the machine type is 497 runtime discoverable, do not have to use this setting. 498 499- vxWorks boot parameters: 500 501 bootvx constructs a valid bootline using the following 502 environments variables: bootfile, ipaddr, serverip, hostname. 503 It loads the vxWorks image pointed bootfile. 504 505 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name 506 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address 507 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server 508 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters 509 510 CONFIG_SYS_VXWORKS_ADD_PARAMS 511 512 Add it at the end of the bootline. E.g "u=username pw=secret" 513 514 Note: If a "bootargs" environment is defined, it will overwride 515 the defaults discussed just above. 516 517- Cache Configuration: 518 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot 519 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot 520 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot 521 522- Cache Configuration for ARM: 523 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache 524 controller 525 CONFIG_SYS_PL310_BASE - Physical base address of PL310 526 controller register space 527 528- Serial Ports: 529 CONFIG_PL010_SERIAL 530 531 Define this if you want support for Amba PrimeCell PL010 UARTs. 532 533 CONFIG_PL011_SERIAL 534 535 Define this if you want support for Amba PrimeCell PL011 UARTs. 536 537 CONFIG_PL011_CLOCK 538 539 If you have Amba PrimeCell PL011 UARTs, set this variable to 540 the clock speed of the UARTs. 541 542 CONFIG_PL01x_PORTS 543 544 If you have Amba PrimeCell PL010 or PL011 UARTs on your board, 545 define this to a list of base addresses for each (supported) 546 port. See e.g. include/configs/versatile.h 547 548 CONFIG_PL011_SERIAL_RLCR 549 550 Some vendor versions of PL011 serial ports (e.g. ST-Ericsson U8500) 551 have separate receive and transmit line control registers. Set 552 this variable to initialize the extra register. 553 554 CONFIG_PL011_SERIAL_FLUSH_ON_INIT 555 556 On some platforms (e.g. U8500) U-Boot is loaded by a second stage 557 boot loader that has already initialized the UART. Define this 558 variable to flush the UART at init time. 559 560 561- Console Interface: 562 Depending on board, define exactly one serial port 563 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2, 564 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial 565 console by defining CONFIG_8xx_CONS_NONE 566 567 Note: if CONFIG_8xx_CONS_NONE is defined, the serial 568 port routines must be defined elsewhere 569 (i.e. serial_init(), serial_getc(), ...) 570 571 CONFIG_CFB_CONSOLE 572 Enables console device for a color framebuffer. Needs following 573 defines (cf. smiLynxEM, i8042) 574 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation 575 (default big endian) 576 VIDEO_HW_RECTFILL graphic chip supports 577 rectangle fill 578 (cf. smiLynxEM) 579 VIDEO_HW_BITBLT graphic chip supports 580 bit-blit (cf. smiLynxEM) 581 VIDEO_VISIBLE_COLS visible pixel columns 582 (cols=pitch) 583 VIDEO_VISIBLE_ROWS visible pixel rows 584 VIDEO_PIXEL_SIZE bytes per pixel 585 VIDEO_DATA_FORMAT graphic data format 586 (0-5, cf. cfb_console.c) 587 VIDEO_FB_ADRS framebuffer address 588 VIDEO_KBD_INIT_FCT keyboard int fct 589 (i.e. i8042_kbd_init()) 590 VIDEO_TSTC_FCT test char fct 591 (i.e. i8042_tstc) 592 VIDEO_GETC_FCT get char fct 593 (i.e. i8042_getc) 594 CONFIG_CONSOLE_CURSOR cursor drawing on/off 595 (requires blink timer 596 cf. i8042.c) 597 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c) 598 CONFIG_CONSOLE_TIME display time/date info in 599 upper right corner 600 (requires CONFIG_CMD_DATE) 601 CONFIG_VIDEO_LOGO display Linux logo in 602 upper left corner 603 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of 604 linux_logo.h for logo. 605 Requires CONFIG_VIDEO_LOGO 606 CONFIG_CONSOLE_EXTRA_INFO 607 additional board info beside 608 the logo 609 610 When CONFIG_CFB_CONSOLE is defined, video console is 611 default i/o. Serial console can be forced with 612 environment 'console=serial'. 613 614 When CONFIG_SILENT_CONSOLE is defined, all console 615 messages (by U-Boot and Linux!) can be silenced with 616 the "silent" environment variable. See 617 doc/README.silent for more information. 618 619- Console Baudrate: 620 CONFIG_BAUDRATE - in bps 621 Select one of the baudrates listed in 622 CONFIG_SYS_BAUDRATE_TABLE, see below. 623 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale 624 625- Console Rx buffer length 626 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define 627 the maximum receive buffer length for the SMC. 628 This option is actual only for 82xx and 8xx possible. 629 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE 630 must be defined, to setup the maximum idle timeout for 631 the SMC. 632 633- Pre-Console Buffer: 634 Prior to the console being initialised (i.e. serial UART 635 initialised etc) all console output is silently discarded. 636 Defining CONFIG_PRE_CONSOLE_BUFFER will cause U-Boot to 637 buffer any console messages prior to the console being 638 initialised to a buffer of size CONFIG_PRE_CON_BUF_SZ 639 bytes located at CONFIG_PRE_CON_BUF_ADDR. The buffer is 640 a circular buffer, so if more than CONFIG_PRE_CON_BUF_SZ 641 bytes are output before the console is initialised, the 642 earlier bytes are discarded. 643 644 'Sane' compilers will generate smaller code if 645 CONFIG_PRE_CON_BUF_SZ is a power of 2 646 647- Pre-console putc(): 648 Prior to the console being initialised, console output is 649 normally silently discarded. This can be annoying if a 650 panic() happens in this time. 651 652 If the CONFIG_PRE_CONSOLE_PUTC option is defined, then 653 U-Boot will call board_pre_console_putc() for each output 654 character in this case, This function should try to output 655 the character if possible, perhaps on all available UARTs 656 (it will need to do this directly, since the console code 657 is not functional yet). Note that if the panic happens 658 early enough, then it is possible that board_init_f() 659 (or even arch_cpu_init() on ARM) has not been called yet. 660 You should init all clocks, GPIOs, etc. that are needed 661 to get the character out. Baud rates will need to default 662 to something sensible. 663 664- Safe printf() functions 665 Define CONFIG_SYS_VSNPRINTF to compile in safe versions of 666 the printf() functions. These are defined in 667 include/vsprintf.h and include snprintf(), vsnprintf() and 668 so on. Code size increase is approximately 300-500 bytes. 669 If this option is not given then these functions will 670 silently discard their buffer size argument - this means 671 you are not getting any overflow checking in this case. 672 673- Boot Delay: CONFIG_BOOTDELAY - in seconds 674 Delay before automatically booting the default image; 675 set to -1 to disable autoboot. 676 677 See doc/README.autoboot for these options that 678 work with CONFIG_BOOTDELAY. None are required. 679 CONFIG_BOOT_RETRY_TIME 680 CONFIG_BOOT_RETRY_MIN 681 CONFIG_AUTOBOOT_KEYED 682 CONFIG_AUTOBOOT_PROMPT 683 CONFIG_AUTOBOOT_DELAY_STR 684 CONFIG_AUTOBOOT_STOP_STR 685 CONFIG_AUTOBOOT_DELAY_STR2 686 CONFIG_AUTOBOOT_STOP_STR2 687 CONFIG_ZERO_BOOTDELAY_CHECK 688 CONFIG_RESET_TO_RETRY 689 690- Autoboot Command: 691 CONFIG_BOOTCOMMAND 692 Only needed when CONFIG_BOOTDELAY is enabled; 693 define a command string that is automatically executed 694 when no character is read on the console interface 695 within "Boot Delay" after reset. 696 697 CONFIG_BOOTARGS 698 This can be used to pass arguments to the bootm 699 command. The value of CONFIG_BOOTARGS goes into the 700 environment value "bootargs". 701 702 CONFIG_RAMBOOT and CONFIG_NFSBOOT 703 The value of these goes into the environment as 704 "ramboot" and "nfsboot" respectively, and can be used 705 as a convenience, when switching between booting from 706 RAM and NFS. 707 708- Pre-Boot Commands: 709 CONFIG_PREBOOT 710 711 When this option is #defined, the existence of the 712 environment variable "preboot" will be checked 713 immediately before starting the CONFIG_BOOTDELAY 714 countdown and/or running the auto-boot command resp. 715 entering interactive mode. 716 717 This feature is especially useful when "preboot" is 718 automatically generated or modified. For an example 719 see the LWMON board specific code: here "preboot" is 720 modified when the user holds down a certain 721 combination of keys on the (special) keyboard when 722 booting the systems 723 724- Serial Download Echo Mode: 725 CONFIG_LOADS_ECHO 726 If defined to 1, all characters received during a 727 serial download (using the "loads" command) are 728 echoed back. This might be needed by some terminal 729 emulations (like "cu"), but may as well just take 730 time on others. This setting #define's the initial 731 value of the "loads_echo" environment variable. 732 733- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined) 734 CONFIG_KGDB_BAUDRATE 735 Select one of the baudrates listed in 736 CONFIG_SYS_BAUDRATE_TABLE, see below. 737 738- Monitor Functions: 739 Monitor commands can be included or excluded 740 from the build by using the #include files 741 "config_cmd_all.h" and #undef'ing unwanted 742 commands, or using "config_cmd_default.h" 743 and augmenting with additional #define's 744 for wanted commands. 745 746 The default command configuration includes all commands 747 except those marked below with a "*". 748 749 CONFIG_CMD_ASKENV * ask for env variable 750 CONFIG_CMD_BDI bdinfo 751 CONFIG_CMD_BEDBUG * Include BedBug Debugger 752 CONFIG_CMD_BMP * BMP support 753 CONFIG_CMD_BSP * Board specific commands 754 CONFIG_CMD_BOOTD bootd 755 CONFIG_CMD_CACHE * icache, dcache 756 CONFIG_CMD_CONSOLE coninfo 757 CONFIG_CMD_CRC32 * crc32 758 CONFIG_CMD_DATE * support for RTC, date/time... 759 CONFIG_CMD_DHCP * DHCP support 760 CONFIG_CMD_DIAG * Diagnostics 761 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands 762 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command 763 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd 764 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command 765 CONFIG_CMD_DTT * Digital Therm and Thermostat 766 CONFIG_CMD_ECHO echo arguments 767 CONFIG_CMD_EDITENV edit env variable 768 CONFIG_CMD_EEPROM * EEPROM read/write support 769 CONFIG_CMD_ELF * bootelf, bootvx 770 CONFIG_CMD_EXPORTENV * export the environment 771 CONFIG_CMD_SAVEENV saveenv 772 CONFIG_CMD_FDC * Floppy Disk Support 773 CONFIG_CMD_FAT * FAT partition support 774 CONFIG_CMD_FDOS * Dos diskette Support 775 CONFIG_CMD_FLASH flinfo, erase, protect 776 CONFIG_CMD_FPGA FPGA device initialization support 777 CONFIG_CMD_GO * the 'go' command (exec code) 778 CONFIG_CMD_GREPENV * search environment 779 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control 780 CONFIG_CMD_I2C * I2C serial bus support 781 CONFIG_CMD_IDE * IDE harddisk support 782 CONFIG_CMD_IMI iminfo 783 CONFIG_CMD_IMLS List all found images 784 CONFIG_CMD_IMMAP * IMMR dump support 785 CONFIG_CMD_IMPORTENV * import an environment 786 CONFIG_CMD_IRQ * irqinfo 787 CONFIG_CMD_ITEST Integer/string test of 2 values 788 CONFIG_CMD_JFFS2 * JFFS2 Support 789 CONFIG_CMD_KGDB * kgdb 790 CONFIG_CMD_LDRINFO ldrinfo (display Blackfin loader) 791 CONFIG_CMD_LOADB loadb 792 CONFIG_CMD_LOADS loads 793 CONFIG_CMD_MD5SUM print md5 message digest 794 (requires CONFIG_CMD_MEMORY and CONFIG_MD5) 795 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base, 796 loop, loopw, mtest 797 CONFIG_CMD_MISC Misc functions like sleep etc 798 CONFIG_CMD_MMC * MMC memory mapped support 799 CONFIG_CMD_MII * MII utility commands 800 CONFIG_CMD_MTDPARTS * MTD partition support 801 CONFIG_CMD_NAND * NAND support 802 CONFIG_CMD_NET bootp, tftpboot, rarpboot 803 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands 804 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command 805 CONFIG_CMD_PCI * pciinfo 806 CONFIG_CMD_PCMCIA * PCMCIA support 807 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network 808 host 809 CONFIG_CMD_PORTIO * Port I/O 810 CONFIG_CMD_REGINFO * Register dump 811 CONFIG_CMD_RUN run command in env variable 812 CONFIG_CMD_SAVES * save S record dump 813 CONFIG_CMD_SCSI * SCSI Support 814 CONFIG_CMD_SDRAM * print SDRAM configuration information 815 (requires CONFIG_CMD_I2C) 816 CONFIG_CMD_SETGETDCR Support for DCR Register access 817 (4xx only) 818 CONFIG_CMD_SHA1SUM print sha1 memory digest 819 (requires CONFIG_CMD_MEMORY) 820 CONFIG_CMD_SOURCE "source" command Support 821 CONFIG_CMD_SPI * SPI serial bus support 822 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode 823 CONFIG_CMD_TFTPPUT * TFTP put command (upload) 824 CONFIG_CMD_TIME * run command and report execution time 825 CONFIG_CMD_USB * USB support 826 CONFIG_CMD_CDP * Cisco Discover Protocol support 827 CONFIG_CMD_FSL * Microblaze FSL support 828 829 830 EXAMPLE: If you want all functions except of network 831 support you can write: 832 833 #include "config_cmd_all.h" 834 #undef CONFIG_CMD_NET 835 836 Other Commands: 837 fdt (flattened device tree) command: CONFIG_OF_LIBFDT 838 839 Note: Don't enable the "icache" and "dcache" commands 840 (configuration option CONFIG_CMD_CACHE) unless you know 841 what you (and your U-Boot users) are doing. Data 842 cache cannot be enabled on systems like the 8xx or 843 8260 (where accesses to the IMMR region must be 844 uncached), and it cannot be disabled on all other 845 systems where we (mis-) use the data cache to hold an 846 initial stack and some data. 847 848 849 XXX - this list needs to get updated! 850 851- Device tree: 852 CONFIG_OF_CONTROL 853 If this variable is defined, U-Boot will use a device tree 854 to configure its devices, instead of relying on statically 855 compiled #defines in the board file. This option is 856 experimental and only available on a few boards. The device 857 tree is available in the global data as gd->fdt_blob. 858 859 U-Boot needs to get its device tree from somewhere. This can 860 be done using one of the two options below: 861 862 CONFIG_OF_EMBED 863 If this variable is defined, U-Boot will embed a device tree 864 binary in its image. This device tree file should be in the 865 board directory and called <soc>-<board>.dts. The binary file 866 is then picked up in board_init_f() and made available through 867 the global data structure as gd->blob. 868 869 CONFIG_OF_SEPARATE 870 If this variable is defined, U-Boot will build a device tree 871 binary. It will be called u-boot.dtb. Architecture-specific 872 code will locate it at run-time. Generally this works by: 873 874 cat u-boot.bin u-boot.dtb >image.bin 875 876 and in fact, U-Boot does this for you, creating a file called 877 u-boot-dtb.bin which is useful in the common case. You can 878 still use the individual files if you need something more 879 exotic. 880 881- Watchdog: 882 CONFIG_WATCHDOG 883 If this variable is defined, it enables watchdog 884 support for the SoC. There must be support in the SoC 885 specific code for a watchdog. For the 8xx and 8260 886 CPUs, the SIU Watchdog feature is enabled in the SYPCR 887 register. When supported for a specific SoC is 888 available, then no further board specific code should 889 be needed to use it. 890 891 CONFIG_HW_WATCHDOG 892 When using a watchdog circuitry external to the used 893 SoC, then define this variable and provide board 894 specific code for the "hw_watchdog_reset" function. 895 896- U-Boot Version: 897 CONFIG_VERSION_VARIABLE 898 If this variable is defined, an environment variable 899 named "ver" is created by U-Boot showing the U-Boot 900 version as printed by the "version" command. 901 This variable is readonly. 902 903- Real-Time Clock: 904 905 When CONFIG_CMD_DATE is selected, the type of the RTC 906 has to be selected, too. Define exactly one of the 907 following options: 908 909 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx 910 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC 911 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC 912 CONFIG_RTC_MC146818 - use MC146818 RTC 913 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC 914 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC 915 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC 916 CONFIG_RTC_DS164x - use Dallas DS164x RTC 917 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC 918 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC 919 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337 920 CONFIG_SYS_RV3029_TCR - enable trickle charger on 921 RV3029 RTC. 922 923 Note that if the RTC uses I2C, then the I2C interface 924 must also be configured. See I2C Support, below. 925 926- GPIO Support: 927 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO 928 CONFIG_PCA953X_INFO - enable pca953x info command 929 930 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of 931 chip-ngpio pairs that tell the PCA953X driver the number of 932 pins supported by a particular chip. 933 934 Note that if the GPIO device uses I2C, then the I2C interface 935 must also be configured. See I2C Support, below. 936 937- Timestamp Support: 938 939 When CONFIG_TIMESTAMP is selected, the timestamp 940 (date and time) of an image is printed by image 941 commands like bootm or iminfo. This option is 942 automatically enabled when you select CONFIG_CMD_DATE . 943 944- Partition Support: 945 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION 946 and/or CONFIG_ISO_PARTITION and/or CONFIG_EFI_PARTITION 947 948 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or 949 CONFIG_CMD_SCSI) you must configure support for at 950 least one partition type as well. 951 952- IDE Reset method: 953 CONFIG_IDE_RESET_ROUTINE - this is defined in several 954 board configurations files but used nowhere! 955 956 CONFIG_IDE_RESET - is this is defined, IDE Reset will 957 be performed by calling the function 958 ide_set_reset(int reset) 959 which has to be defined in a board specific file 960 961- ATAPI Support: 962 CONFIG_ATAPI 963 964 Set this to enable ATAPI support. 965 966- LBA48 Support 967 CONFIG_LBA48 968 969 Set this to enable support for disks larger than 137GB 970 Also look at CONFIG_SYS_64BIT_LBA. 971 Whithout these , LBA48 support uses 32bit variables and will 'only' 972 support disks up to 2.1TB. 973 974 CONFIG_SYS_64BIT_LBA: 975 When enabled, makes the IDE subsystem use 64bit sector addresses. 976 Default is 32bit. 977 978- SCSI Support: 979 At the moment only there is only support for the 980 SYM53C8XX SCSI controller; define 981 CONFIG_SCSI_SYM53C8XX to enable it. 982 983 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and 984 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID * 985 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the 986 maximum numbers of LUNs, SCSI ID's and target 987 devices. 988 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz) 989 990- NETWORK Support (PCI): 991 CONFIG_E1000 992 Support for Intel 8254x/8257x gigabit chips. 993 994 CONFIG_E1000_SPI 995 Utility code for direct access to the SPI bus on Intel 8257x. 996 This does not do anything useful unless you set at least one 997 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC. 998 999 CONFIG_E1000_SPI_GENERIC 1000 Allow generic access to the SPI bus on the Intel 8257x, for 1001 example with the "sspi" command. 1002 1003 CONFIG_CMD_E1000 1004 Management command for E1000 devices. When used on devices 1005 with SPI support you can reprogram the EEPROM from U-Boot. 1006 1007 CONFIG_E1000_FALLBACK_MAC 1008 default MAC for empty EEPROM after production. 1009 1010 CONFIG_EEPRO100 1011 Support for Intel 82557/82559/82559ER chips. 1012 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM 1013 write routine for first time initialisation. 1014 1015 CONFIG_TULIP 1016 Support for Digital 2114x chips. 1017 Optional CONFIG_TULIP_SELECT_MEDIA for board specific 1018 modem chip initialisation (KS8761/QS6611). 1019 1020 CONFIG_NATSEMI 1021 Support for National dp83815 chips. 1022 1023 CONFIG_NS8382X 1024 Support for National dp8382[01] gigabit chips. 1025 1026- NETWORK Support (other): 1027 1028 CONFIG_DRIVER_AT91EMAC 1029 Support for AT91RM9200 EMAC. 1030 1031 CONFIG_RMII 1032 Define this to use reduced MII inteface 1033 1034 CONFIG_DRIVER_AT91EMAC_QUIET 1035 If this defined, the driver is quiet. 1036 The driver doen't show link status messages. 1037 1038 CONFIG_CALXEDA_XGMAC 1039 Support for the Calxeda XGMAC device 1040 1041 CONFIG_DRIVER_LAN91C96 1042 Support for SMSC's LAN91C96 chips. 1043 1044 CONFIG_LAN91C96_BASE 1045 Define this to hold the physical address 1046 of the LAN91C96's I/O space 1047 1048 CONFIG_LAN91C96_USE_32_BIT 1049 Define this to enable 32 bit addressing 1050 1051 CONFIG_DRIVER_SMC91111 1052 Support for SMSC's LAN91C111 chip 1053 1054 CONFIG_SMC91111_BASE 1055 Define this to hold the physical address 1056 of the device (I/O space) 1057 1058 CONFIG_SMC_USE_32_BIT 1059 Define this if data bus is 32 bits 1060 1061 CONFIG_SMC_USE_IOFUNCS 1062 Define this to use i/o functions instead of macros 1063 (some hardware wont work with macros) 1064 1065 CONFIG_DRIVER_TI_EMAC 1066 Support for davinci emac 1067 1068 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT 1069 Define this if you have more then 3 PHYs. 1070 1071 CONFIG_FTGMAC100 1072 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet 1073 1074 CONFIG_FTGMAC100_EGIGA 1075 Define this to use GE link update with gigabit PHY. 1076 Define this if FTGMAC100 is connected to gigabit PHY. 1077 If your system has 10/100 PHY only, it might not occur 1078 wrong behavior. Because PHY usually return timeout or 1079 useless data when polling gigabit status and gigabit 1080 control registers. This behavior won't affect the 1081 correctnessof 10/100 link speed update. 1082 1083 CONFIG_SMC911X 1084 Support for SMSC's LAN911x and LAN921x chips 1085 1086 CONFIG_SMC911X_BASE 1087 Define this to hold the physical address 1088 of the device (I/O space) 1089 1090 CONFIG_SMC911X_32_BIT 1091 Define this if data bus is 32 bits 1092 1093 CONFIG_SMC911X_16_BIT 1094 Define this if data bus is 16 bits. If your processor 1095 automatically converts one 32 bit word to two 16 bit 1096 words you may also try CONFIG_SMC911X_32_BIT. 1097 1098 CONFIG_SH_ETHER 1099 Support for Renesas on-chip Ethernet controller 1100 1101 CONFIG_SH_ETHER_USE_PORT 1102 Define the number of ports to be used 1103 1104 CONFIG_SH_ETHER_PHY_ADDR 1105 Define the ETH PHY's address 1106 1107 CONFIG_SH_ETHER_CACHE_WRITEBACK 1108 If this option is set, the driver enables cache flush. 1109 1110- TPM Support: 1111 CONFIG_GENERIC_LPC_TPM 1112 Support for generic parallel port TPM devices. Only one device 1113 per system is supported at this time. 1114 1115 CONFIG_TPM_TIS_BASE_ADDRESS 1116 Base address where the generic TPM device is mapped 1117 to. Contemporary x86 systems usually map it at 1118 0xfed40000. 1119 1120- USB Support: 1121 At the moment only the UHCI host controller is 1122 supported (PIP405, MIP405, MPC5200); define 1123 CONFIG_USB_UHCI to enable it. 1124 define CONFIG_USB_KEYBOARD to enable the USB Keyboard 1125 and define CONFIG_USB_STORAGE to enable the USB 1126 storage devices. 1127 Note: 1128 Supported are USB Keyboards and USB Floppy drives 1129 (TEAC FD-05PUB). 1130 MPC5200 USB requires additional defines: 1131 CONFIG_USB_CLOCK 1132 for 528 MHz Clock: 0x0001bbbb 1133 CONFIG_PSC3_USB 1134 for USB on PSC3 1135 CONFIG_USB_CONFIG 1136 for differential drivers: 0x00001000 1137 for single ended drivers: 0x00005000 1138 for differential drivers on PSC3: 0x00000100 1139 for single ended drivers on PSC3: 0x00004100 1140 CONFIG_SYS_USB_EVENT_POLL 1141 May be defined to allow interrupt polling 1142 instead of using asynchronous interrupts 1143 1144- USB Device: 1145 Define the below if you wish to use the USB console. 1146 Once firmware is rebuilt from a serial console issue the 1147 command "setenv stdin usbtty; setenv stdout usbtty" and 1148 attach your USB cable. The Unix command "dmesg" should print 1149 it has found a new device. The environment variable usbtty 1150 can be set to gserial or cdc_acm to enable your device to 1151 appear to a USB host as a Linux gserial device or a 1152 Common Device Class Abstract Control Model serial device. 1153 If you select usbtty = gserial you should be able to enumerate 1154 a Linux host by 1155 # modprobe usbserial vendor=0xVendorID product=0xProductID 1156 else if using cdc_acm, simply setting the environment 1157 variable usbtty to be cdc_acm should suffice. The following 1158 might be defined in YourBoardName.h 1159 1160 CONFIG_USB_DEVICE 1161 Define this to build a UDC device 1162 1163 CONFIG_USB_TTY 1164 Define this to have a tty type of device available to 1165 talk to the UDC device 1166 1167 CONFIG_SYS_CONSOLE_IS_IN_ENV 1168 Define this if you want stdin, stdout &/or stderr to 1169 be set to usbtty. 1170 1171 mpc8xx: 1172 CONFIG_SYS_USB_EXTC_CLK 0xBLAH 1173 Derive USB clock from external clock "blah" 1174 - CONFIG_SYS_USB_EXTC_CLK 0x02 1175 1176 CONFIG_SYS_USB_BRG_CLK 0xBLAH 1177 Derive USB clock from brgclk 1178 - CONFIG_SYS_USB_BRG_CLK 0x04 1179 1180 If you have a USB-IF assigned VendorID then you may wish to 1181 define your own vendor specific values either in BoardName.h 1182 or directly in usbd_vendor_info.h. If you don't define 1183 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME, 1184 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot 1185 should pretend to be a Linux device to it's target host. 1186 1187 CONFIG_USBD_MANUFACTURER 1188 Define this string as the name of your company for 1189 - CONFIG_USBD_MANUFACTURER "my company" 1190 1191 CONFIG_USBD_PRODUCT_NAME 1192 Define this string as the name of your product 1193 - CONFIG_USBD_PRODUCT_NAME "acme usb device" 1194 1195 CONFIG_USBD_VENDORID 1196 Define this as your assigned Vendor ID from the USB 1197 Implementors Forum. This *must* be a genuine Vendor ID 1198 to avoid polluting the USB namespace. 1199 - CONFIG_USBD_VENDORID 0xFFFF 1200 1201 CONFIG_USBD_PRODUCTID 1202 Define this as the unique Product ID 1203 for your device 1204 - CONFIG_USBD_PRODUCTID 0xFFFF 1205 1206- ULPI Layer Support: 1207 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via 1208 the generic ULPI layer. The generic layer accesses the ULPI PHY 1209 via the platform viewport, so you need both the genric layer and 1210 the viewport enabled. Currently only Chipidea/ARC based 1211 viewport is supported. 1212 To enable the ULPI layer support, define CONFIG_USB_ULPI and 1213 CONFIG_USB_ULPI_VIEWPORT in your board configuration file. 1214 1215- MMC Support: 1216 The MMC controller on the Intel PXA is supported. To 1217 enable this define CONFIG_MMC. The MMC can be 1218 accessed from the boot prompt by mapping the device 1219 to physical memory similar to flash. Command line is 1220 enabled with CONFIG_CMD_MMC. The MMC driver also works with 1221 the FAT fs. This is enabled with CONFIG_CMD_FAT. 1222 1223 CONFIG_SH_MMCIF 1224 Support for Renesas on-chip MMCIF controller 1225 1226 CONFIG_SH_MMCIF_ADDR 1227 Define the base address of MMCIF registers 1228 1229 CONFIG_SH_MMCIF_CLK 1230 Define the clock frequency for MMCIF 1231 1232- Journaling Flash filesystem support: 1233 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE, 1234 CONFIG_JFFS2_NAND_DEV 1235 Define these for a default partition on a NAND device 1236 1237 CONFIG_SYS_JFFS2_FIRST_SECTOR, 1238 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS 1239 Define these for a default partition on a NOR device 1240 1241 CONFIG_SYS_JFFS_CUSTOM_PART 1242 Define this to create an own partition. You have to provide a 1243 function struct part_info* jffs2_part_info(int part_num) 1244 1245 If you define only one JFFS2 partition you may also want to 1246 #define CONFIG_SYS_JFFS_SINGLE_PART 1 1247 to disable the command chpart. This is the default when you 1248 have not defined a custom partition 1249 1250- FAT(File Allocation Table) filesystem write function support: 1251 CONFIG_FAT_WRITE 1252 Support for saving memory data as a file 1253 in FAT formatted partition 1254 1255- Keyboard Support: 1256 CONFIG_ISA_KEYBOARD 1257 1258 Define this to enable standard (PC-Style) keyboard 1259 support 1260 1261 CONFIG_I8042_KBD 1262 Standard PC keyboard driver with US (is default) and 1263 GERMAN key layout (switch via environment 'keymap=de') support. 1264 Export function i8042_kbd_init, i8042_tstc and i8042_getc 1265 for cfb_console. Supports cursor blinking. 1266 1267- Video support: 1268 CONFIG_VIDEO 1269 1270 Define this to enable video support (for output to 1271 video). 1272 1273 CONFIG_VIDEO_CT69000 1274 1275 Enable Chips & Technologies 69000 Video chip 1276 1277 CONFIG_VIDEO_SMI_LYNXEM 1278 Enable Silicon Motion SMI 712/710/810 Video chip. The 1279 video output is selected via environment 'videoout' 1280 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is 1281 assumed. 1282 1283 For the CT69000 and SMI_LYNXEM drivers, videomode is 1284 selected via environment 'videomode'. Two different ways 1285 are possible: 1286 - "videomode=num" 'num' is a standard LiLo mode numbers. 1287 Following standard modes are supported (* is default): 1288 1289 Colors 640x480 800x600 1024x768 1152x864 1280x1024 1290 -------------+--------------------------------------------- 1291 8 bits | 0x301* 0x303 0x305 0x161 0x307 1292 15 bits | 0x310 0x313 0x316 0x162 0x319 1293 16 bits | 0x311 0x314 0x317 0x163 0x31A 1294 24 bits | 0x312 0x315 0x318 ? 0x31B 1295 -------------+--------------------------------------------- 1296 (i.e. setenv videomode 317; saveenv; reset;) 1297 1298 - "videomode=bootargs" all the video parameters are parsed 1299 from the bootargs. (See drivers/video/videomodes.c) 1300 1301 1302 CONFIG_VIDEO_SED13806 1303 Enable Epson SED13806 driver. This driver supports 8bpp 1304 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP 1305 or CONFIG_VIDEO_SED13806_16BPP 1306 1307 CONFIG_FSL_DIU_FB 1308 Enable the Freescale DIU video driver. Reference boards for 1309 SOCs that have a DIU should define this macro to enable DIU 1310 support, and should also define these other macros: 1311 1312 CONFIG_SYS_DIU_ADDR 1313 CONFIG_VIDEO 1314 CONFIG_CMD_BMP 1315 CONFIG_CFB_CONSOLE 1316 CONFIG_VIDEO_SW_CURSOR 1317 CONFIG_VGA_AS_SINGLE_DEVICE 1318 CONFIG_VIDEO_LOGO 1319 CONFIG_VIDEO_BMP_LOGO 1320 1321 The DIU driver will look for the 'video-mode' environment 1322 variable, and if defined, enable the DIU as a console during 1323 boot. See the documentation file README.video for a 1324 description of this variable. 1325 1326- Keyboard Support: 1327 CONFIG_KEYBOARD 1328 1329 Define this to enable a custom keyboard support. 1330 This simply calls drv_keyboard_init() which must be 1331 defined in your board-specific files. 1332 The only board using this so far is RBC823. 1333 1334- LCD Support: CONFIG_LCD 1335 1336 Define this to enable LCD support (for output to LCD 1337 display); also select one of the supported displays 1338 by defining one of these: 1339 1340 CONFIG_ATMEL_LCD: 1341 1342 HITACHI TX09D70VM1CCA, 3.5", 240x320. 1343 1344 CONFIG_NEC_NL6448AC33: 1345 1346 NEC NL6448AC33-18. Active, color, single scan. 1347 1348 CONFIG_NEC_NL6448BC20 1349 1350 NEC NL6448BC20-08. 6.5", 640x480. 1351 Active, color, single scan. 1352 1353 CONFIG_NEC_NL6448BC33_54 1354 1355 NEC NL6448BC33-54. 10.4", 640x480. 1356 Active, color, single scan. 1357 1358 CONFIG_SHARP_16x9 1359 1360 Sharp 320x240. Active, color, single scan. 1361 It isn't 16x9, and I am not sure what it is. 1362 1363 CONFIG_SHARP_LQ64D341 1364 1365 Sharp LQ64D341 display, 640x480. 1366 Active, color, single scan. 1367 1368 CONFIG_HLD1045 1369 1370 HLD1045 display, 640x480. 1371 Active, color, single scan. 1372 1373 CONFIG_OPTREX_BW 1374 1375 Optrex CBL50840-2 NF-FW 99 22 M5 1376 or 1377 Hitachi LMG6912RPFC-00T 1378 or 1379 Hitachi SP14Q002 1380 1381 320x240. Black & white. 1382 1383 Normally display is black on white background; define 1384 CONFIG_SYS_WHITE_ON_BLACK to get it inverted. 1385 1386- Splash Screen Support: CONFIG_SPLASH_SCREEN 1387 1388 If this option is set, the environment is checked for 1389 a variable "splashimage". If found, the usual display 1390 of logo, copyright and system information on the LCD 1391 is suppressed and the BMP image at the address 1392 specified in "splashimage" is loaded instead. The 1393 console is redirected to the "nulldev", too. This 1394 allows for a "silent" boot where a splash screen is 1395 loaded very quickly after power-on. 1396 1397 CONFIG_SPLASH_SCREEN_ALIGN 1398 1399 If this option is set the splash image can be freely positioned 1400 on the screen. Environment variable "splashpos" specifies the 1401 position as "x,y". If a positive number is given it is used as 1402 number of pixel from left/top. If a negative number is given it 1403 is used as number of pixel from right/bottom. You can also 1404 specify 'm' for centering the image. 1405 1406 Example: 1407 setenv splashpos m,m 1408 => image at center of screen 1409 1410 setenv splashpos 30,20 1411 => image at x = 30 and y = 20 1412 1413 setenv splashpos -10,m 1414 => vertically centered image 1415 at x = dspWidth - bmpWidth - 9 1416 1417- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP 1418 1419 If this option is set, additionally to standard BMP 1420 images, gzipped BMP images can be displayed via the 1421 splashscreen support or the bmp command. 1422 1423- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8 1424 1425 If this option is set, 8-bit RLE compressed BMP images 1426 can be displayed via the splashscreen support or the 1427 bmp command. 1428 1429- Compression support: 1430 CONFIG_BZIP2 1431 1432 If this option is set, support for bzip2 compressed 1433 images is included. If not, only uncompressed and gzip 1434 compressed images are supported. 1435 1436 NOTE: the bzip2 algorithm requires a lot of RAM, so 1437 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should 1438 be at least 4MB. 1439 1440 CONFIG_LZMA 1441 1442 If this option is set, support for lzma compressed 1443 images is included. 1444 1445 Note: The LZMA algorithm adds between 2 and 4KB of code and it 1446 requires an amount of dynamic memory that is given by the 1447 formula: 1448 1449 (1846 + 768 << (lc + lp)) * sizeof(uint16) 1450 1451 Where lc and lp stand for, respectively, Literal context bits 1452 and Literal pos bits. 1453 1454 This value is upper-bounded by 14MB in the worst case. Anyway, 1455 for a ~4MB large kernel image, we have lc=3 and lp=0 for a 1456 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is 1457 a very small buffer. 1458 1459 Use the lzmainfo tool to determinate the lc and lp values and 1460 then calculate the amount of needed dynamic memory (ensuring 1461 the appropriate CONFIG_SYS_MALLOC_LEN value). 1462 1463- MII/PHY support: 1464 CONFIG_PHY_ADDR 1465 1466 The address of PHY on MII bus. 1467 1468 CONFIG_PHY_CLOCK_FREQ (ppc4xx) 1469 1470 The clock frequency of the MII bus 1471 1472 CONFIG_PHY_GIGE 1473 1474 If this option is set, support for speed/duplex 1475 detection of gigabit PHY is included. 1476 1477 CONFIG_PHY_RESET_DELAY 1478 1479 Some PHY like Intel LXT971A need extra delay after 1480 reset before any MII register access is possible. 1481 For such PHY, set this option to the usec delay 1482 required. (minimum 300usec for LXT971A) 1483 1484 CONFIG_PHY_CMD_DELAY (ppc4xx) 1485 1486 Some PHY like Intel LXT971A need extra delay after 1487 command issued before MII status register can be read 1488 1489- Ethernet address: 1490 CONFIG_ETHADDR 1491 CONFIG_ETH1ADDR 1492 CONFIG_ETH2ADDR 1493 CONFIG_ETH3ADDR 1494 CONFIG_ETH4ADDR 1495 CONFIG_ETH5ADDR 1496 1497 Define a default value for Ethernet address to use 1498 for the respective Ethernet interface, in case this 1499 is not determined automatically. 1500 1501- IP address: 1502 CONFIG_IPADDR 1503 1504 Define a default value for the IP address to use for 1505 the default Ethernet interface, in case this is not 1506 determined through e.g. bootp. 1507 (Environment variable "ipaddr") 1508 1509- Server IP address: 1510 CONFIG_SERVERIP 1511 1512 Defines a default value for the IP address of a TFTP 1513 server to contact when using the "tftboot" command. 1514 (Environment variable "serverip") 1515 1516 CONFIG_KEEP_SERVERADDR 1517 1518 Keeps the server's MAC address, in the env 'serveraddr' 1519 for passing to bootargs (like Linux's netconsole option) 1520 1521- Gateway IP address: 1522 CONFIG_GATEWAYIP 1523 1524 Defines a default value for the IP address of the 1525 default router where packets to other networks are 1526 sent to. 1527 (Environment variable "gatewayip") 1528 1529- Subnet mask: 1530 CONFIG_NETMASK 1531 1532 Defines a default value for the subnet mask (or 1533 routing prefix) which is used to determine if an IP 1534 address belongs to the local subnet or needs to be 1535 forwarded through a router. 1536 (Environment variable "netmask") 1537 1538- Multicast TFTP Mode: 1539 CONFIG_MCAST_TFTP 1540 1541 Defines whether you want to support multicast TFTP as per 1542 rfc-2090; for example to work with atftp. Lets lots of targets 1543 tftp down the same boot image concurrently. Note: the Ethernet 1544 driver in use must provide a function: mcast() to join/leave a 1545 multicast group. 1546 1547- BOOTP Recovery Mode: 1548 CONFIG_BOOTP_RANDOM_DELAY 1549 1550 If you have many targets in a network that try to 1551 boot using BOOTP, you may want to avoid that all 1552 systems send out BOOTP requests at precisely the same 1553 moment (which would happen for instance at recovery 1554 from a power failure, when all systems will try to 1555 boot, thus flooding the BOOTP server. Defining 1556 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 1557 inserted before sending out BOOTP requests. The 1558 following delays are inserted then: 1559 1560 1st BOOTP request: delay 0 ... 1 sec 1561 2nd BOOTP request: delay 0 ... 2 sec 1562 3rd BOOTP request: delay 0 ... 4 sec 1563 4th and following 1564 BOOTP requests: delay 0 ... 8 sec 1565 1566- DHCP Advanced Options: 1567 You can fine tune the DHCP functionality by defining 1568 CONFIG_BOOTP_* symbols: 1569 1570 CONFIG_BOOTP_SUBNETMASK 1571 CONFIG_BOOTP_GATEWAY 1572 CONFIG_BOOTP_HOSTNAME 1573 CONFIG_BOOTP_NISDOMAIN 1574 CONFIG_BOOTP_BOOTPATH 1575 CONFIG_BOOTP_BOOTFILESIZE 1576 CONFIG_BOOTP_DNS 1577 CONFIG_BOOTP_DNS2 1578 CONFIG_BOOTP_SEND_HOSTNAME 1579 CONFIG_BOOTP_NTPSERVER 1580 CONFIG_BOOTP_TIMEOFFSET 1581 CONFIG_BOOTP_VENDOREX 1582 1583 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip 1584 environment variable, not the BOOTP server. 1585 1586 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS 1587 serverip from a DHCP server, it is possible that more 1588 than one DNS serverip is offered to the client. 1589 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS 1590 serverip will be stored in the additional environment 1591 variable "dnsip2". The first DNS serverip is always 1592 stored in the variable "dnsip", when CONFIG_BOOTP_DNS 1593 is defined. 1594 1595 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable 1596 to do a dynamic update of a DNS server. To do this, they 1597 need the hostname of the DHCP requester. 1598 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content 1599 of the "hostname" environment variable is passed as 1600 option 12 to the DHCP server. 1601 1602 CONFIG_BOOTP_DHCP_REQUEST_DELAY 1603 1604 A 32bit value in microseconds for a delay between 1605 receiving a "DHCP Offer" and sending the "DHCP Request". 1606 This fixes a problem with certain DHCP servers that don't 1607 respond 100% of the time to a "DHCP request". E.g. On an 1608 AT91RM9200 processor running at 180MHz, this delay needed 1609 to be *at least* 15,000 usec before a Windows Server 2003 1610 DHCP server would reply 100% of the time. I recommend at 1611 least 50,000 usec to be safe. The alternative is to hope 1612 that one of the retries will be successful but note that 1613 the DHCP timeout and retry process takes a longer than 1614 this delay. 1615 1616 - CDP Options: 1617 CONFIG_CDP_DEVICE_ID 1618 1619 The device id used in CDP trigger frames. 1620 1621 CONFIG_CDP_DEVICE_ID_PREFIX 1622 1623 A two character string which is prefixed to the MAC address 1624 of the device. 1625 1626 CONFIG_CDP_PORT_ID 1627 1628 A printf format string which contains the ascii name of 1629 the port. Normally is set to "eth%d" which sets 1630 eth0 for the first Ethernet, eth1 for the second etc. 1631 1632 CONFIG_CDP_CAPABILITIES 1633 1634 A 32bit integer which indicates the device capabilities; 1635 0x00000010 for a normal host which does not forwards. 1636 1637 CONFIG_CDP_VERSION 1638 1639 An ascii string containing the version of the software. 1640 1641 CONFIG_CDP_PLATFORM 1642 1643 An ascii string containing the name of the platform. 1644 1645 CONFIG_CDP_TRIGGER 1646 1647 A 32bit integer sent on the trigger. 1648 1649 CONFIG_CDP_POWER_CONSUMPTION 1650 1651 A 16bit integer containing the power consumption of the 1652 device in .1 of milliwatts. 1653 1654 CONFIG_CDP_APPLIANCE_VLAN_TYPE 1655 1656 A byte containing the id of the VLAN. 1657 1658- Status LED: CONFIG_STATUS_LED 1659 1660 Several configurations allow to display the current 1661 status using a LED. For instance, the LED will blink 1662 fast while running U-Boot code, stop blinking as 1663 soon as a reply to a BOOTP request was received, and 1664 start blinking slow once the Linux kernel is running 1665 (supported by a status LED driver in the Linux 1666 kernel). Defining CONFIG_STATUS_LED enables this 1667 feature in U-Boot. 1668 1669- CAN Support: CONFIG_CAN_DRIVER 1670 1671 Defining CONFIG_CAN_DRIVER enables CAN driver support 1672 on those systems that support this (optional) 1673 feature, like the TQM8xxL modules. 1674 1675- I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C 1676 1677 These enable I2C serial bus commands. Defining either of 1678 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will 1679 include the appropriate I2C driver for the selected CPU. 1680 1681 This will allow you to use i2c commands at the u-boot 1682 command line (as long as you set CONFIG_CMD_I2C in 1683 CONFIG_COMMANDS) and communicate with i2c based realtime 1684 clock chips. See common/cmd_i2c.c for a description of the 1685 command line interface. 1686 1687 CONFIG_HARD_I2C selects a hardware I2C controller. 1688 1689 CONFIG_SOFT_I2C configures u-boot to use a software (aka 1690 bit-banging) driver instead of CPM or similar hardware 1691 support for I2C. 1692 1693 There are several other quantities that must also be 1694 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C. 1695 1696 In both cases you will need to define CONFIG_SYS_I2C_SPEED 1697 to be the frequency (in Hz) at which you wish your i2c bus 1698 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie 1699 the CPU's i2c node address). 1700 1701 Now, the u-boot i2c code for the mpc8xx 1702 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node 1703 and so its address should therefore be cleared to 0 (See, 1704 eg, MPC823e User's Manual p.16-473). So, set 1705 CONFIG_SYS_I2C_SLAVE to 0. 1706 1707 CONFIG_SYS_I2C_INIT_MPC5XXX 1708 1709 When a board is reset during an i2c bus transfer 1710 chips might think that the current transfer is still 1711 in progress. Reset the slave devices by sending start 1712 commands until the slave device responds. 1713 1714 That's all that's required for CONFIG_HARD_I2C. 1715 1716 If you use the software i2c interface (CONFIG_SOFT_I2C) 1717 then the following macros need to be defined (examples are 1718 from include/configs/lwmon.h): 1719 1720 I2C_INIT 1721 1722 (Optional). Any commands necessary to enable the I2C 1723 controller or configure ports. 1724 1725 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) 1726 1727 I2C_PORT 1728 1729 (Only for MPC8260 CPU). The I/O port to use (the code 1730 assumes both bits are on the same port). Valid values 1731 are 0..3 for ports A..D. 1732 1733 I2C_ACTIVE 1734 1735 The code necessary to make the I2C data line active 1736 (driven). If the data line is open collector, this 1737 define can be null. 1738 1739 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) 1740 1741 I2C_TRISTATE 1742 1743 The code necessary to make the I2C data line tri-stated 1744 (inactive). If the data line is open collector, this 1745 define can be null. 1746 1747 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) 1748 1749 I2C_READ 1750 1751 Code that returns TRUE if the I2C data line is high, 1752 FALSE if it is low. 1753 1754 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) 1755 1756 I2C_SDA(bit) 1757 1758 If <bit> is TRUE, sets the I2C data line high. If it 1759 is FALSE, it clears it (low). 1760 1761 eg: #define I2C_SDA(bit) \ 1762 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ 1763 else immr->im_cpm.cp_pbdat &= ~PB_SDA 1764 1765 I2C_SCL(bit) 1766 1767 If <bit> is TRUE, sets the I2C clock line high. If it 1768 is FALSE, it clears it (low). 1769 1770 eg: #define I2C_SCL(bit) \ 1771 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ 1772 else immr->im_cpm.cp_pbdat &= ~PB_SCL 1773 1774 I2C_DELAY 1775 1776 This delay is invoked four times per clock cycle so this 1777 controls the rate of data transfer. The data rate thus 1778 is 1 / (I2C_DELAY * 4). Often defined to be something 1779 like: 1780 1781 #define I2C_DELAY udelay(2) 1782 1783 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA 1784 1785 If your arch supports the generic GPIO framework (asm/gpio.h), 1786 then you may alternatively define the two GPIOs that are to be 1787 used as SCL / SDA. Any of the previous I2C_xxx macros will 1788 have GPIO-based defaults assigned to them as appropriate. 1789 1790 You should define these to the GPIO value as given directly to 1791 the generic GPIO functions. 1792 1793 CONFIG_SYS_I2C_INIT_BOARD 1794 1795 When a board is reset during an i2c bus transfer 1796 chips might think that the current transfer is still 1797 in progress. On some boards it is possible to access 1798 the i2c SCLK line directly, either by using the 1799 processor pin as a GPIO or by having a second pin 1800 connected to the bus. If this option is defined a 1801 custom i2c_init_board() routine in boards/xxx/board.c 1802 is run early in the boot sequence. 1803 1804 CONFIG_SYS_I2C_BOARD_LATE_INIT 1805 1806 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is 1807 defined a custom i2c_board_late_init() routine in 1808 boards/xxx/board.c is run AFTER the operations in i2c_init() 1809 is completed. This callpoint can be used to unreset i2c bus 1810 using CPU i2c controller register accesses for CPUs whose i2c 1811 controller provide such a method. It is called at the end of 1812 i2c_init() to allow i2c_init operations to setup the i2c bus 1813 controller on the CPU (e.g. setting bus speed & slave address). 1814 1815 CONFIG_I2CFAST (PPC405GP|PPC405EP only) 1816 1817 This option enables configuration of bi_iic_fast[] flags 1818 in u-boot bd_info structure based on u-boot environment 1819 variable "i2cfast". (see also i2cfast) 1820 1821 CONFIG_I2C_MULTI_BUS 1822 1823 This option allows the use of multiple I2C buses, each of which 1824 must have a controller. At any point in time, only one bus is 1825 active. To switch to a different bus, use the 'i2c dev' command. 1826 Note that bus numbering is zero-based. 1827 1828 CONFIG_SYS_I2C_NOPROBES 1829 1830 This option specifies a list of I2C devices that will be skipped 1831 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS 1832 is set, specify a list of bus-device pairs. Otherwise, specify 1833 a 1D array of device addresses 1834 1835 e.g. 1836 #undef CONFIG_I2C_MULTI_BUS 1837 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68} 1838 1839 will skip addresses 0x50 and 0x68 on a board with one I2C bus 1840 1841 #define CONFIG_I2C_MULTI_BUS 1842 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}} 1843 1844 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1 1845 1846 CONFIG_SYS_SPD_BUS_NUM 1847 1848 If defined, then this indicates the I2C bus number for DDR SPD. 1849 If not defined, then U-Boot assumes that SPD is on I2C bus 0. 1850 1851 CONFIG_SYS_RTC_BUS_NUM 1852 1853 If defined, then this indicates the I2C bus number for the RTC. 1854 If not defined, then U-Boot assumes that RTC is on I2C bus 0. 1855 1856 CONFIG_SYS_DTT_BUS_NUM 1857 1858 If defined, then this indicates the I2C bus number for the DTT. 1859 If not defined, then U-Boot assumes that DTT is on I2C bus 0. 1860 1861 CONFIG_SYS_I2C_DTT_ADDR: 1862 1863 If defined, specifies the I2C address of the DTT device. 1864 If not defined, then U-Boot uses predefined value for 1865 specified DTT device. 1866 1867 CONFIG_FSL_I2C 1868 1869 Define this option if you want to use Freescale's I2C driver in 1870 drivers/i2c/fsl_i2c.c. 1871 1872 CONFIG_I2C_MUX 1873 1874 Define this option if you have I2C devices reached over 1 .. n 1875 I2C Muxes like the pca9544a. This option addes a new I2C 1876 Command "i2c bus [muxtype:muxaddr:muxchannel]" which adds a 1877 new I2C Bus to the existing I2C Busses. If you select the 1878 new Bus with "i2c dev", u-bbot sends first the commandos for 1879 the muxes to activate this new "bus". 1880 1881 CONFIG_I2C_MULTI_BUS must be also defined, to use this 1882 feature! 1883 1884 Example: 1885 Adding a new I2C Bus reached over 2 pca9544a muxes 1886 The First mux with address 70 and channel 6 1887 The Second mux with address 71 and channel 4 1888 1889 => i2c bus pca9544a:70:6:pca9544a:71:4 1890 1891 Use the "i2c bus" command without parameter, to get a list 1892 of I2C Busses with muxes: 1893 1894 => i2c bus 1895 Busses reached over muxes: 1896 Bus ID: 2 1897 reached over Mux(es): 1898 pca9544a@70 ch: 4 1899 Bus ID: 3 1900 reached over Mux(es): 1901 pca9544a@70 ch: 6 1902 pca9544a@71 ch: 4 1903 => 1904 1905 If you now switch to the new I2C Bus 3 with "i2c dev 3" 1906 u-boot first sends the command to the mux@70 to enable 1907 channel 6, and then the command to the mux@71 to enable 1908 the channel 4. 1909 1910 After that, you can use the "normal" i2c commands as 1911 usual to communicate with your I2C devices behind 1912 the 2 muxes. 1913 1914 This option is actually implemented for the bitbanging 1915 algorithm in common/soft_i2c.c and for the Hardware I2C 1916 Bus on the MPC8260. But it should be not so difficult 1917 to add this option to other architectures. 1918 1919 CONFIG_SOFT_I2C_READ_REPEATED_START 1920 1921 defining this will force the i2c_read() function in 1922 the soft_i2c driver to perform an I2C repeated start 1923 between writing the address pointer and reading the 1924 data. If this define is omitted the default behaviour 1925 of doing a stop-start sequence will be used. Most I2C 1926 devices can use either method, but some require one or 1927 the other. 1928 1929- SPI Support: CONFIG_SPI 1930 1931 Enables SPI driver (so far only tested with 1932 SPI EEPROM, also an instance works with Crystal A/D and 1933 D/As on the SACSng board) 1934 1935 CONFIG_SH_SPI 1936 1937 Enables the driver for SPI controller on SuperH. Currently 1938 only SH7757 is supported. 1939 1940 CONFIG_SPI_X 1941 1942 Enables extended (16-bit) SPI EEPROM addressing. 1943 (symmetrical to CONFIG_I2C_X) 1944 1945 CONFIG_SOFT_SPI 1946 1947 Enables a software (bit-bang) SPI driver rather than 1948 using hardware support. This is a general purpose 1949 driver that only requires three general I/O port pins 1950 (two outputs, one input) to function. If this is 1951 defined, the board configuration must define several 1952 SPI configuration items (port pins to use, etc). For 1953 an example, see include/configs/sacsng.h. 1954 1955 CONFIG_HARD_SPI 1956 1957 Enables a hardware SPI driver for general-purpose reads 1958 and writes. As with CONFIG_SOFT_SPI, the board configuration 1959 must define a list of chip-select function pointers. 1960 Currently supported on some MPC8xxx processors. For an 1961 example, see include/configs/mpc8349emds.h. 1962 1963 CONFIG_MXC_SPI 1964 1965 Enables the driver for the SPI controllers on i.MX and MXC 1966 SoCs. Currently i.MX31/35/51 are supported. 1967 1968- FPGA Support: CONFIG_FPGA 1969 1970 Enables FPGA subsystem. 1971 1972 CONFIG_FPGA_<vendor> 1973 1974 Enables support for specific chip vendors. 1975 (ALTERA, XILINX) 1976 1977 CONFIG_FPGA_<family> 1978 1979 Enables support for FPGA family. 1980 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX) 1981 1982 CONFIG_FPGA_COUNT 1983 1984 Specify the number of FPGA devices to support. 1985 1986 CONFIG_SYS_FPGA_PROG_FEEDBACK 1987 1988 Enable printing of hash marks during FPGA configuration. 1989 1990 CONFIG_SYS_FPGA_CHECK_BUSY 1991 1992 Enable checks on FPGA configuration interface busy 1993 status by the configuration function. This option 1994 will require a board or device specific function to 1995 be written. 1996 1997 CONFIG_FPGA_DELAY 1998 1999 If defined, a function that provides delays in the FPGA 2000 configuration driver. 2001 2002 CONFIG_SYS_FPGA_CHECK_CTRLC 2003 Allow Control-C to interrupt FPGA configuration 2004 2005 CONFIG_SYS_FPGA_CHECK_ERROR 2006 2007 Check for configuration errors during FPGA bitfile 2008 loading. For example, abort during Virtex II 2009 configuration if the INIT_B line goes low (which 2010 indicated a CRC error). 2011 2012 CONFIG_SYS_FPGA_WAIT_INIT 2013 2014 Maximum time to wait for the INIT_B line to deassert 2015 after PROB_B has been deasserted during a Virtex II 2016 FPGA configuration sequence. The default time is 500 2017 ms. 2018 2019 CONFIG_SYS_FPGA_WAIT_BUSY 2020 2021 Maximum time to wait for BUSY to deassert during 2022 Virtex II FPGA configuration. The default is 5 ms. 2023 2024 CONFIG_SYS_FPGA_WAIT_CONFIG 2025 2026 Time to wait after FPGA configuration. The default is 2027 200 ms. 2028 2029- Configuration Management: 2030 CONFIG_IDENT_STRING 2031 2032 If defined, this string will be added to the U-Boot 2033 version information (U_BOOT_VERSION) 2034 2035- Vendor Parameter Protection: 2036 2037 U-Boot considers the values of the environment 2038 variables "serial#" (Board Serial Number) and 2039 "ethaddr" (Ethernet Address) to be parameters that 2040 are set once by the board vendor / manufacturer, and 2041 protects these variables from casual modification by 2042 the user. Once set, these variables are read-only, 2043 and write or delete attempts are rejected. You can 2044 change this behaviour: 2045 2046 If CONFIG_ENV_OVERWRITE is #defined in your config 2047 file, the write protection for vendor parameters is 2048 completely disabled. Anybody can change or delete 2049 these parameters. 2050 2051 Alternatively, if you #define _both_ CONFIG_ETHADDR 2052 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 2053 Ethernet address is installed in the environment, 2054 which can be changed exactly ONCE by the user. [The 2055 serial# is unaffected by this, i. e. it remains 2056 read-only.] 2057 2058- Protected RAM: 2059 CONFIG_PRAM 2060 2061 Define this variable to enable the reservation of 2062 "protected RAM", i. e. RAM which is not overwritten 2063 by U-Boot. Define CONFIG_PRAM to hold the number of 2064 kB you want to reserve for pRAM. You can overwrite 2065 this default value by defining an environment 2066 variable "pram" to the number of kB you want to 2067 reserve. Note that the board info structure will 2068 still show the full amount of RAM. If pRAM is 2069 reserved, a new environment variable "mem" will 2070 automatically be defined to hold the amount of 2071 remaining RAM in a form that can be passed as boot 2072 argument to Linux, for instance like that: 2073 2074 setenv bootargs ... mem=\${mem} 2075 saveenv 2076 2077 This way you can tell Linux not to use this memory, 2078 either, which results in a memory region that will 2079 not be affected by reboots. 2080 2081 *WARNING* If your board configuration uses automatic 2082 detection of the RAM size, you must make sure that 2083 this memory test is non-destructive. So far, the 2084 following board configurations are known to be 2085 "pRAM-clean": 2086 2087 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL, 2088 HERMES, IP860, RPXlite, LWMON, LANTEC, 2089 FLAGADM, TQM8260 2090 2091- Error Recovery: 2092 CONFIG_PANIC_HANG 2093 2094 Define this variable to stop the system in case of a 2095 fatal error, so that you have to reset it manually. 2096 This is probably NOT a good idea for an embedded 2097 system where you want the system to reboot 2098 automatically as fast as possible, but it may be 2099 useful during development since you can try to debug 2100 the conditions that lead to the situation. 2101 2102 CONFIG_NET_RETRY_COUNT 2103 2104 This variable defines the number of retries for 2105 network operations like ARP, RARP, TFTP, or BOOTP 2106 before giving up the operation. If not defined, a 2107 default value of 5 is used. 2108 2109 CONFIG_ARP_TIMEOUT 2110 2111 Timeout waiting for an ARP reply in milliseconds. 2112 2113- Command Interpreter: 2114 CONFIG_AUTO_COMPLETE 2115 2116 Enable auto completion of commands using TAB. 2117 2118 Note that this feature has NOT been implemented yet 2119 for the "hush" shell. 2120 2121 2122 CONFIG_SYS_HUSH_PARSER 2123 2124 Define this variable to enable the "hush" shell (from 2125 Busybox) as command line interpreter, thus enabling 2126 powerful command line syntax like 2127 if...then...else...fi conditionals or `&&' and '||' 2128 constructs ("shell scripts"). 2129 2130 If undefined, you get the old, much simpler behaviour 2131 with a somewhat smaller memory footprint. 2132 2133 2134 CONFIG_SYS_PROMPT_HUSH_PS2 2135 2136 This defines the secondary prompt string, which is 2137 printed when the command interpreter needs more input 2138 to complete a command. Usually "> ". 2139 2140 Note: 2141 2142 In the current implementation, the local variables 2143 space and global environment variables space are 2144 separated. Local variables are those you define by 2145 simply typing `name=value'. To access a local 2146 variable later on, you have write `$name' or 2147 `${name}'; to execute the contents of a variable 2148 directly type `$name' at the command prompt. 2149 2150 Global environment variables are those you use 2151 setenv/printenv to work with. To run a command stored 2152 in such a variable, you need to use the run command, 2153 and you must not use the '$' sign to access them. 2154 2155 To store commands and special characters in a 2156 variable, please use double quotation marks 2157 surrounding the whole text of the variable, instead 2158 of the backslashes before semicolons and special 2159 symbols. 2160 2161- Commandline Editing and History: 2162 CONFIG_CMDLINE_EDITING 2163 2164 Enable editing and History functions for interactive 2165 commandline input operations 2166 2167- Default Environment: 2168 CONFIG_EXTRA_ENV_SETTINGS 2169 2170 Define this to contain any number of null terminated 2171 strings (variable = value pairs) that will be part of 2172 the default environment compiled into the boot image. 2173 2174 For example, place something like this in your 2175 board's config file: 2176 2177 #define CONFIG_EXTRA_ENV_SETTINGS \ 2178 "myvar1=value1\0" \ 2179 "myvar2=value2\0" 2180 2181 Warning: This method is based on knowledge about the 2182 internal format how the environment is stored by the 2183 U-Boot code. This is NOT an official, exported 2184 interface! Although it is unlikely that this format 2185 will change soon, there is no guarantee either. 2186 You better know what you are doing here. 2187 2188 Note: overly (ab)use of the default environment is 2189 discouraged. Make sure to check other ways to preset 2190 the environment like the "source" command or the 2191 boot command first. 2192 2193- DataFlash Support: 2194 CONFIG_HAS_DATAFLASH 2195 2196 Defining this option enables DataFlash features and 2197 allows to read/write in Dataflash via the standard 2198 commands cp, md... 2199 2200- SystemACE Support: 2201 CONFIG_SYSTEMACE 2202 2203 Adding this option adds support for Xilinx SystemACE 2204 chips attached via some sort of local bus. The address 2205 of the chip must also be defined in the 2206 CONFIG_SYS_SYSTEMACE_BASE macro. For example: 2207 2208 #define CONFIG_SYSTEMACE 2209 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000 2210 2211 When SystemACE support is added, the "ace" device type 2212 becomes available to the fat commands, i.e. fatls. 2213 2214- TFTP Fixed UDP Port: 2215 CONFIG_TFTP_PORT 2216 2217 If this is defined, the environment variable tftpsrcp 2218 is used to supply the TFTP UDP source port value. 2219 If tftpsrcp isn't defined, the normal pseudo-random port 2220 number generator is used. 2221 2222 Also, the environment variable tftpdstp is used to supply 2223 the TFTP UDP destination port value. If tftpdstp isn't 2224 defined, the normal port 69 is used. 2225 2226 The purpose for tftpsrcp is to allow a TFTP server to 2227 blindly start the TFTP transfer using the pre-configured 2228 target IP address and UDP port. This has the effect of 2229 "punching through" the (Windows XP) firewall, allowing 2230 the remainder of the TFTP transfer to proceed normally. 2231 A better solution is to properly configure the firewall, 2232 but sometimes that is not allowed. 2233 2234- Show boot progress: 2235 CONFIG_SHOW_BOOT_PROGRESS 2236 2237 Defining this option allows to add some board- 2238 specific code (calling a user-provided function 2239 "show_boot_progress(int)") that enables you to show 2240 the system's boot progress on some display (for 2241 example, some LED's) on your board. At the moment, 2242 the following checkpoints are implemented: 2243 2244Legacy uImage format: 2245 2246 Arg Where When 2247 1 common/cmd_bootm.c before attempting to boot an image 2248 -1 common/cmd_bootm.c Image header has bad magic number 2249 2 common/cmd_bootm.c Image header has correct magic number 2250 -2 common/cmd_bootm.c Image header has bad checksum 2251 3 common/cmd_bootm.c Image header has correct checksum 2252 -3 common/cmd_bootm.c Image data has bad checksum 2253 4 common/cmd_bootm.c Image data has correct checksum 2254 -4 common/cmd_bootm.c Image is for unsupported architecture 2255 5 common/cmd_bootm.c Architecture check OK 2256 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi) 2257 6 common/cmd_bootm.c Image Type check OK 2258 -6 common/cmd_bootm.c gunzip uncompression error 2259 -7 common/cmd_bootm.c Unimplemented compression type 2260 7 common/cmd_bootm.c Uncompression OK 2261 8 common/cmd_bootm.c No uncompress/copy overwrite error 2262 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 2263 2264 9 common/image.c Start initial ramdisk verification 2265 -10 common/image.c Ramdisk header has bad magic number 2266 -11 common/image.c Ramdisk header has bad checksum 2267 10 common/image.c Ramdisk header is OK 2268 -12 common/image.c Ramdisk data has bad checksum 2269 11 common/image.c Ramdisk data has correct checksum 2270 12 common/image.c Ramdisk verification complete, start loading 2271 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk) 2272 13 common/image.c Start multifile image verification 2273 14 common/image.c No initial ramdisk, no multifile, continue. 2274 2275 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS 2276 2277 -30 arch/powerpc/lib/board.c Fatal error, hang the system 2278 -31 post/post.c POST test failed, detected by post_output_backlog() 2279 -32 post/post.c POST test failed, detected by post_run_single() 2280 2281 34 common/cmd_doc.c before loading a Image from a DOC device 2282 -35 common/cmd_doc.c Bad usage of "doc" command 2283 35 common/cmd_doc.c correct usage of "doc" command 2284 -36 common/cmd_doc.c No boot device 2285 36 common/cmd_doc.c correct boot device 2286 -37 common/cmd_doc.c Unknown Chip ID on boot device 2287 37 common/cmd_doc.c correct chip ID found, device available 2288 -38 common/cmd_doc.c Read Error on boot device 2289 38 common/cmd_doc.c reading Image header from DOC device OK 2290 -39 common/cmd_doc.c Image header has bad magic number 2291 39 common/cmd_doc.c Image header has correct magic number 2292 -40 common/cmd_doc.c Error reading Image from DOC device 2293 40 common/cmd_doc.c Image header has correct magic number 2294 41 common/cmd_ide.c before loading a Image from a IDE device 2295 -42 common/cmd_ide.c Bad usage of "ide" command 2296 42 common/cmd_ide.c correct usage of "ide" command 2297 -43 common/cmd_ide.c No boot device 2298 43 common/cmd_ide.c boot device found 2299 -44 common/cmd_ide.c Device not available 2300 44 common/cmd_ide.c Device available 2301 -45 common/cmd_ide.c wrong partition selected 2302 45 common/cmd_ide.c partition selected 2303 -46 common/cmd_ide.c Unknown partition table 2304 46 common/cmd_ide.c valid partition table found 2305 -47 common/cmd_ide.c Invalid partition type 2306 47 common/cmd_ide.c correct partition type 2307 -48 common/cmd_ide.c Error reading Image Header on boot device 2308 48 common/cmd_ide.c reading Image Header from IDE device OK 2309 -49 common/cmd_ide.c Image header has bad magic number 2310 49 common/cmd_ide.c Image header has correct magic number 2311 -50 common/cmd_ide.c Image header has bad checksum 2312 50 common/cmd_ide.c Image header has correct checksum 2313 -51 common/cmd_ide.c Error reading Image from IDE device 2314 51 common/cmd_ide.c reading Image from IDE device OK 2315 52 common/cmd_nand.c before loading a Image from a NAND device 2316 -53 common/cmd_nand.c Bad usage of "nand" command 2317 53 common/cmd_nand.c correct usage of "nand" command 2318 -54 common/cmd_nand.c No boot device 2319 54 common/cmd_nand.c boot device found 2320 -55 common/cmd_nand.c Unknown Chip ID on boot device 2321 55 common/cmd_nand.c correct chip ID found, device available 2322 -56 common/cmd_nand.c Error reading Image Header on boot device 2323 56 common/cmd_nand.c reading Image Header from NAND device OK 2324 -57 common/cmd_nand.c Image header has bad magic number 2325 57 common/cmd_nand.c Image header has correct magic number 2326 -58 common/cmd_nand.c Error reading Image from NAND device 2327 58 common/cmd_nand.c reading Image from NAND device OK 2328 2329 -60 common/env_common.c Environment has a bad CRC, using default 2330 2331 64 net/eth.c starting with Ethernet configuration. 2332 -64 net/eth.c no Ethernet found. 2333 65 net/eth.c Ethernet found. 2334 2335 -80 common/cmd_net.c usage wrong 2336 80 common/cmd_net.c before calling NetLoop() 2337 -81 common/cmd_net.c some error in NetLoop() occurred 2338 81 common/cmd_net.c NetLoop() back without error 2339 -82 common/cmd_net.c size == 0 (File with size 0 loaded) 2340 82 common/cmd_net.c trying automatic boot 2341 83 common/cmd_net.c running "source" command 2342 -83 common/cmd_net.c some error in automatic boot or "source" command 2343 84 common/cmd_net.c end without errors 2344 2345FIT uImage format: 2346 2347 Arg Where When 2348 100 common/cmd_bootm.c Kernel FIT Image has correct format 2349 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format 2350 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration 2351 -101 common/cmd_bootm.c Can't get configuration for kernel subimage 2352 102 common/cmd_bootm.c Kernel unit name specified 2353 -103 common/cmd_bootm.c Can't get kernel subimage node offset 2354 103 common/cmd_bootm.c Found configuration node 2355 104 common/cmd_bootm.c Got kernel subimage node offset 2356 -104 common/cmd_bootm.c Kernel subimage hash verification failed 2357 105 common/cmd_bootm.c Kernel subimage hash verification OK 2358 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture 2359 106 common/cmd_bootm.c Architecture check OK 2360 -106 common/cmd_bootm.c Kernel subimage has wrong type 2361 107 common/cmd_bootm.c Kernel subimage type OK 2362 -107 common/cmd_bootm.c Can't get kernel subimage data/size 2363 108 common/cmd_bootm.c Got kernel subimage data/size 2364 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT) 2365 -109 common/cmd_bootm.c Can't get kernel subimage type 2366 -110 common/cmd_bootm.c Can't get kernel subimage comp 2367 -111 common/cmd_bootm.c Can't get kernel subimage os 2368 -112 common/cmd_bootm.c Can't get kernel subimage load address 2369 -113 common/cmd_bootm.c Image uncompress/copy overwrite error 2370 2371 120 common/image.c Start initial ramdisk verification 2372 -120 common/image.c Ramdisk FIT image has incorrect format 2373 121 common/image.c Ramdisk FIT image has correct format 2374 122 common/image.c No ramdisk subimage unit name, using configuration 2375 -122 common/image.c Can't get configuration for ramdisk subimage 2376 123 common/image.c Ramdisk unit name specified 2377 -124 common/image.c Can't get ramdisk subimage node offset 2378 125 common/image.c Got ramdisk subimage node offset 2379 -125 common/image.c Ramdisk subimage hash verification failed 2380 126 common/image.c Ramdisk subimage hash verification OK 2381 -126 common/image.c Ramdisk subimage for unsupported architecture 2382 127 common/image.c Architecture check OK 2383 -127 common/image.c Can't get ramdisk subimage data/size 2384 128 common/image.c Got ramdisk subimage data/size 2385 129 common/image.c Can't get ramdisk load address 2386 -129 common/image.c Got ramdisk load address 2387 2388 -130 common/cmd_doc.c Incorrect FIT image format 2389 131 common/cmd_doc.c FIT image format OK 2390 2391 -140 common/cmd_ide.c Incorrect FIT image format 2392 141 common/cmd_ide.c FIT image format OK 2393 2394 -150 common/cmd_nand.c Incorrect FIT image format 2395 151 common/cmd_nand.c FIT image format OK 2396 2397- Standalone program support: 2398 CONFIG_STANDALONE_LOAD_ADDR 2399 2400 This option defines a board specific value for the 2401 address where standalone program gets loaded, thus 2402 overwriting the architecture dependent default 2403 settings. 2404 2405- Frame Buffer Address: 2406 CONFIG_FB_ADDR 2407 2408 Define CONFIG_FB_ADDR if you want to use specific 2409 address for frame buffer. 2410 Then system will reserve the frame buffer address to 2411 defined address instead of lcd_setmem (this function 2412 grabs the memory for frame buffer by panel's size). 2413 2414 Please see board_init_f function. 2415 2416- Automatic software updates via TFTP server 2417 CONFIG_UPDATE_TFTP 2418 CONFIG_UPDATE_TFTP_CNT_MAX 2419 CONFIG_UPDATE_TFTP_MSEC_MAX 2420 2421 These options enable and control the auto-update feature; 2422 for a more detailed description refer to doc/README.update. 2423 2424- MTD Support (mtdparts command, UBI support) 2425 CONFIG_MTD_DEVICE 2426 2427 Adds the MTD device infrastructure from the Linux kernel. 2428 Needed for mtdparts command support. 2429 2430 CONFIG_MTD_PARTITIONS 2431 2432 Adds the MTD partitioning infrastructure from the Linux 2433 kernel. Needed for UBI support. 2434 2435- SPL framework 2436 CONFIG_SPL 2437 Enable building of SPL globally. 2438 2439 CONFIG_SPL_TEXT_BASE 2440 TEXT_BASE for linking the SPL binary. 2441 2442 CONFIG_SPL_LDSCRIPT 2443 LDSCRIPT for linking the SPL binary. 2444 2445 CONFIG_SPL_LIBCOMMON_SUPPORT 2446 Support for common/libcommon.o in SPL binary 2447 2448 CONFIG_SPL_LIBDISK_SUPPORT 2449 Support for disk/libdisk.o in SPL binary 2450 2451 CONFIG_SPL_I2C_SUPPORT 2452 Support for drivers/i2c/libi2c.o in SPL binary 2453 2454 CONFIG_SPL_GPIO_SUPPORT 2455 Support for drivers/gpio/libgpio.o in SPL binary 2456 2457 CONFIG_SPL_MMC_SUPPORT 2458 Support for drivers/mmc/libmmc.o in SPL binary 2459 2460 CONFIG_SPL_SERIAL_SUPPORT 2461 Support for drivers/serial/libserial.o in SPL binary 2462 2463 CONFIG_SPL_SPI_FLASH_SUPPORT 2464 Support for drivers/mtd/spi/libspi_flash.o in SPL binary 2465 2466 CONFIG_SPL_SPI_SUPPORT 2467 Support for drivers/spi/libspi.o in SPL binary 2468 2469 CONFIG_SPL_FAT_SUPPORT 2470 Support for fs/fat/libfat.o in SPL binary 2471 2472 CONFIG_SPL_LIBGENERIC_SUPPORT 2473 Support for lib/libgeneric.o in SPL binary 2474 2475Modem Support: 2476-------------- 2477 2478[so far only for SMDK2400 boards] 2479 2480- Modem support enable: 2481 CONFIG_MODEM_SUPPORT 2482 2483- RTS/CTS Flow control enable: 2484 CONFIG_HWFLOW 2485 2486- Modem debug support: 2487 CONFIG_MODEM_SUPPORT_DEBUG 2488 2489 Enables debugging stuff (char screen[1024], dbg()) 2490 for modem support. Useful only with BDI2000. 2491 2492- Interrupt support (PPC): 2493 2494 There are common interrupt_init() and timer_interrupt() 2495 for all PPC archs. interrupt_init() calls interrupt_init_cpu() 2496 for CPU specific initialization. interrupt_init_cpu() 2497 should set decrementer_count to appropriate value. If 2498 CPU resets decrementer automatically after interrupt 2499 (ppc4xx) it should set decrementer_count to zero. 2500 timer_interrupt() calls timer_interrupt_cpu() for CPU 2501 specific handling. If board has watchdog / status_led 2502 / other_activity_monitor it works automatically from 2503 general timer_interrupt(). 2504 2505- General: 2506 2507 In the target system modem support is enabled when a 2508 specific key (key combination) is pressed during 2509 power-on. Otherwise U-Boot will boot normally 2510 (autoboot). The key_pressed() function is called from 2511 board_init(). Currently key_pressed() is a dummy 2512 function, returning 1 and thus enabling modem 2513 initialization. 2514 2515 If there are no modem init strings in the 2516 environment, U-Boot proceed to autoboot; the 2517 previous output (banner, info printfs) will be 2518 suppressed, though. 2519 2520 See also: doc/README.Modem 2521 2522Board initialization settings: 2523------------------------------ 2524 2525During Initialization u-boot calls a number of board specific functions 2526to allow the preparation of board specific prerequisites, e.g. pin setup 2527before drivers are initialized. To enable these callbacks the 2528following configuration macros have to be defined. Currently this is 2529architecture specific, so please check arch/your_architecture/lib/board.c 2530typically in board_init_f() and board_init_r(). 2531 2532- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f() 2533- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r() 2534- CONFIG_BOARD_LATE_INIT: Call board_late_init() 2535- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init() 2536 2537Configuration Settings: 2538----------------------- 2539 2540- CONFIG_SYS_LONGHELP: Defined when you want long help messages included; 2541 undefine this when you're short of memory. 2542 2543- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default 2544 width of the commands listed in the 'help' command output. 2545 2546- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to 2547 prompt for user input. 2548 2549- CONFIG_SYS_CBSIZE: Buffer size for input from the Console 2550 2551- CONFIG_SYS_PBSIZE: Buffer size for Console output 2552 2553- CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands 2554 2555- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to 2556 the application (usually a Linux kernel) when it is 2557 booted 2558 2559- CONFIG_SYS_BAUDRATE_TABLE: 2560 List of legal baudrate settings for this board. 2561 2562- CONFIG_SYS_CONSOLE_INFO_QUIET 2563 Suppress display of console information at boot. 2564 2565- CONFIG_SYS_CONSOLE_IS_IN_ENV 2566 If the board specific function 2567 extern int overwrite_console (void); 2568 returns 1, the stdin, stderr and stdout are switched to the 2569 serial port, else the settings in the environment are used. 2570 2571- CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE 2572 Enable the call to overwrite_console(). 2573 2574- CONFIG_SYS_CONSOLE_ENV_OVERWRITE 2575 Enable overwrite of previous console environment settings. 2576 2577- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END: 2578 Begin and End addresses of the area used by the 2579 simple memory test. 2580 2581- CONFIG_SYS_ALT_MEMTEST: 2582 Enable an alternate, more extensive memory test. 2583 2584- CONFIG_SYS_MEMTEST_SCRATCH: 2585 Scratch address used by the alternate memory test 2586 You only need to set this if address zero isn't writeable 2587 2588- CONFIG_SYS_MEM_TOP_HIDE (PPC only): 2589 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header, 2590 this specified memory area will get subtracted from the top 2591 (end) of RAM and won't get "touched" at all by U-Boot. By 2592 fixing up gd->ram_size the Linux kernel should gets passed 2593 the now "corrected" memory size and won't touch it either. 2594 This should work for arch/ppc and arch/powerpc. Only Linux 2595 board ports in arch/powerpc with bootwrapper support that 2596 recalculate the memory size from the SDRAM controller setup 2597 will have to get fixed in Linux additionally. 2598 2599 This option can be used as a workaround for the 440EPx/GRx 2600 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't 2601 be touched. 2602 2603 WARNING: Please make sure that this value is a multiple of 2604 the Linux page size (normally 4k). If this is not the case, 2605 then the end address of the Linux memory will be located at a 2606 non page size aligned address and this could cause major 2607 problems. 2608 2609- CONFIG_SYS_TFTP_LOADADDR: 2610 Default load address for network file downloads 2611 2612- CONFIG_SYS_LOADS_BAUD_CHANGE: 2613 Enable temporary baudrate change while serial download 2614 2615- CONFIG_SYS_SDRAM_BASE: 2616 Physical start address of SDRAM. _Must_ be 0 here. 2617 2618- CONFIG_SYS_MBIO_BASE: 2619 Physical start address of Motherboard I/O (if using a 2620 Cogent motherboard) 2621 2622- CONFIG_SYS_FLASH_BASE: 2623 Physical start address of Flash memory. 2624 2625- CONFIG_SYS_MONITOR_BASE: 2626 Physical start address of boot monitor code (set by 2627 make config files to be same as the text base address 2628 (CONFIG_SYS_TEXT_BASE) used when linking) - same as 2629 CONFIG_SYS_FLASH_BASE when booting from flash. 2630 2631- CONFIG_SYS_MONITOR_LEN: 2632 Size of memory reserved for monitor code, used to 2633 determine _at_compile_time_ (!) if the environment is 2634 embedded within the U-Boot image, or in a separate 2635 flash sector. 2636 2637- CONFIG_SYS_MALLOC_LEN: 2638 Size of DRAM reserved for malloc() use. 2639 2640- CONFIG_SYS_BOOTM_LEN: 2641 Normally compressed uImages are limited to an 2642 uncompressed size of 8 MBytes. If this is not enough, 2643 you can define CONFIG_SYS_BOOTM_LEN in your board config file 2644 to adjust this setting to your needs. 2645 2646- CONFIG_SYS_BOOTMAPSZ: 2647 Maximum size of memory mapped by the startup code of 2648 the Linux kernel; all data that must be processed by 2649 the Linux kernel (bd_info, boot arguments, FDT blob if 2650 used) must be put below this limit, unless "bootm_low" 2651 enviroment variable is defined and non-zero. In such case 2652 all data for the Linux kernel must be between "bootm_low" 2653 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment 2654 variable "bootm_mapsize" will override the value of 2655 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined, 2656 then the value in "bootm_size" will be used instead. 2657 2658- CONFIG_SYS_BOOT_RAMDISK_HIGH: 2659 Enable initrd_high functionality. If defined then the 2660 initrd_high feature is enabled and the bootm ramdisk subcommand 2661 is enabled. 2662 2663- CONFIG_SYS_BOOT_GET_CMDLINE: 2664 Enables allocating and saving kernel cmdline in space between 2665 "bootm_low" and "bootm_low" + BOOTMAPSZ. 2666 2667- CONFIG_SYS_BOOT_GET_KBD: 2668 Enables allocating and saving a kernel copy of the bd_info in 2669 space between "bootm_low" and "bootm_low" + BOOTMAPSZ. 2670 2671- CONFIG_SYS_MAX_FLASH_BANKS: 2672 Max number of Flash memory banks 2673 2674- CONFIG_SYS_MAX_FLASH_SECT: 2675 Max number of sectors on a Flash chip 2676 2677- CONFIG_SYS_FLASH_ERASE_TOUT: 2678 Timeout for Flash erase operations (in ms) 2679 2680- CONFIG_SYS_FLASH_WRITE_TOUT: 2681 Timeout for Flash write operations (in ms) 2682 2683- CONFIG_SYS_FLASH_LOCK_TOUT 2684 Timeout for Flash set sector lock bit operation (in ms) 2685 2686- CONFIG_SYS_FLASH_UNLOCK_TOUT 2687 Timeout for Flash clear lock bits operation (in ms) 2688 2689- CONFIG_SYS_FLASH_PROTECTION 2690 If defined, hardware flash sectors protection is used 2691 instead of U-Boot software protection. 2692 2693- CONFIG_SYS_DIRECT_FLASH_TFTP: 2694 2695 Enable TFTP transfers directly to flash memory; 2696 without this option such a download has to be 2697 performed in two steps: (1) download to RAM, and (2) 2698 copy from RAM to flash. 2699 2700 The two-step approach is usually more reliable, since 2701 you can check if the download worked before you erase 2702 the flash, but in some situations (when system RAM is 2703 too limited to allow for a temporary copy of the 2704 downloaded image) this option may be very useful. 2705 2706- CONFIG_SYS_FLASH_CFI: 2707 Define if the flash driver uses extra elements in the 2708 common flash structure for storing flash geometry. 2709 2710- CONFIG_FLASH_CFI_DRIVER 2711 This option also enables the building of the cfi_flash driver 2712 in the drivers directory 2713 2714- CONFIG_FLASH_CFI_MTD 2715 This option enables the building of the cfi_mtd driver 2716 in the drivers directory. The driver exports CFI flash 2717 to the MTD layer. 2718 2719- CONFIG_SYS_FLASH_USE_BUFFER_WRITE 2720 Use buffered writes to flash. 2721 2722- CONFIG_FLASH_SPANSION_S29WS_N 2723 s29ws-n MirrorBit flash has non-standard addresses for buffered 2724 write commands. 2725 2726- CONFIG_SYS_FLASH_QUIET_TEST 2727 If this option is defined, the common CFI flash doesn't 2728 print it's warning upon not recognized FLASH banks. This 2729 is useful, if some of the configured banks are only 2730 optionally available. 2731 2732- CONFIG_FLASH_SHOW_PROGRESS 2733 If defined (must be an integer), print out countdown 2734 digits and dots. Recommended value: 45 (9..1) for 80 2735 column displays, 15 (3..1) for 40 column displays. 2736 2737- CONFIG_SYS_RX_ETH_BUFFER: 2738 Defines the number of Ethernet receive buffers. On some 2739 Ethernet controllers it is recommended to set this value 2740 to 8 or even higher (EEPRO100 or 405 EMAC), since all 2741 buffers can be full shortly after enabling the interface 2742 on high Ethernet traffic. 2743 Defaults to 4 if not defined. 2744 2745- CONFIG_ENV_MAX_ENTRIES 2746 2747 Maximum number of entries in the hash table that is used 2748 internally to store the environment settings. The default 2749 setting is supposed to be generous and should work in most 2750 cases. This setting can be used to tune behaviour; see 2751 lib/hashtable.c for details. 2752 2753The following definitions that deal with the placement and management 2754of environment data (variable area); in general, we support the 2755following configurations: 2756 2757- CONFIG_BUILD_ENVCRC: 2758 2759 Builds up envcrc with the target environment so that external utils 2760 may easily extract it and embed it in final U-Boot images. 2761 2762- CONFIG_ENV_IS_IN_FLASH: 2763 2764 Define this if the environment is in flash memory. 2765 2766 a) The environment occupies one whole flash sector, which is 2767 "embedded" in the text segment with the U-Boot code. This 2768 happens usually with "bottom boot sector" or "top boot 2769 sector" type flash chips, which have several smaller 2770 sectors at the start or the end. For instance, such a 2771 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In 2772 such a case you would place the environment in one of the 2773 4 kB sectors - with U-Boot code before and after it. With 2774 "top boot sector" type flash chips, you would put the 2775 environment in one of the last sectors, leaving a gap 2776 between U-Boot and the environment. 2777 2778 - CONFIG_ENV_OFFSET: 2779 2780 Offset of environment data (variable area) to the 2781 beginning of flash memory; for instance, with bottom boot 2782 type flash chips the second sector can be used: the offset 2783 for this sector is given here. 2784 2785 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE. 2786 2787 - CONFIG_ENV_ADDR: 2788 2789 This is just another way to specify the start address of 2790 the flash sector containing the environment (instead of 2791 CONFIG_ENV_OFFSET). 2792 2793 - CONFIG_ENV_SECT_SIZE: 2794 2795 Size of the sector containing the environment. 2796 2797 2798 b) Sometimes flash chips have few, equal sized, BIG sectors. 2799 In such a case you don't want to spend a whole sector for 2800 the environment. 2801 2802 - CONFIG_ENV_SIZE: 2803 2804 If you use this in combination with CONFIG_ENV_IS_IN_FLASH 2805 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part 2806 of this flash sector for the environment. This saves 2807 memory for the RAM copy of the environment. 2808 2809 It may also save flash memory if you decide to use this 2810 when your environment is "embedded" within U-Boot code, 2811 since then the remainder of the flash sector could be used 2812 for U-Boot code. It should be pointed out that this is 2813 STRONGLY DISCOURAGED from a robustness point of view: 2814 updating the environment in flash makes it always 2815 necessary to erase the WHOLE sector. If something goes 2816 wrong before the contents has been restored from a copy in 2817 RAM, your target system will be dead. 2818 2819 - CONFIG_ENV_ADDR_REDUND 2820 CONFIG_ENV_SIZE_REDUND 2821 2822 These settings describe a second storage area used to hold 2823 a redundant copy of the environment data, so that there is 2824 a valid backup copy in case there is a power failure during 2825 a "saveenv" operation. 2826 2827BE CAREFUL! Any changes to the flash layout, and some changes to the 2828source code will make it necessary to adapt <board>/u-boot.lds* 2829accordingly! 2830 2831 2832- CONFIG_ENV_IS_IN_NVRAM: 2833 2834 Define this if you have some non-volatile memory device 2835 (NVRAM, battery buffered SRAM) which you want to use for the 2836 environment. 2837 2838 - CONFIG_ENV_ADDR: 2839 - CONFIG_ENV_SIZE: 2840 2841 These two #defines are used to determine the memory area you 2842 want to use for environment. It is assumed that this memory 2843 can just be read and written to, without any special 2844 provision. 2845 2846BE CAREFUL! The first access to the environment happens quite early 2847in U-Boot initalization (when we try to get the setting of for the 2848console baudrate). You *MUST* have mapped your NVRAM area then, or 2849U-Boot will hang. 2850 2851Please note that even with NVRAM we still use a copy of the 2852environment in RAM: we could work on NVRAM directly, but we want to 2853keep settings there always unmodified except somebody uses "saveenv" 2854to save the current settings. 2855 2856 2857- CONFIG_ENV_IS_IN_EEPROM: 2858 2859 Use this if you have an EEPROM or similar serial access 2860 device and a driver for it. 2861 2862 - CONFIG_ENV_OFFSET: 2863 - CONFIG_ENV_SIZE: 2864 2865 These two #defines specify the offset and size of the 2866 environment area within the total memory of your EEPROM. 2867 2868 - CONFIG_SYS_I2C_EEPROM_ADDR: 2869 If defined, specified the chip address of the EEPROM device. 2870 The default address is zero. 2871 2872 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS: 2873 If defined, the number of bits used to address bytes in a 2874 single page in the EEPROM device. A 64 byte page, for example 2875 would require six bits. 2876 2877 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS: 2878 If defined, the number of milliseconds to delay between 2879 page writes. The default is zero milliseconds. 2880 2881 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN: 2882 The length in bytes of the EEPROM memory array address. Note 2883 that this is NOT the chip address length! 2884 2885 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW: 2886 EEPROM chips that implement "address overflow" are ones 2887 like Catalyst 24WC04/08/16 which has 9/10/11 bits of 2888 address and the extra bits end up in the "chip address" bit 2889 slots. This makes a 24WC08 (1Kbyte) chip look like four 256 2890 byte chips. 2891 2892 Note that we consider the length of the address field to 2893 still be one byte because the extra address bits are hidden 2894 in the chip address. 2895 2896 - CONFIG_SYS_EEPROM_SIZE: 2897 The size in bytes of the EEPROM device. 2898 2899 - CONFIG_ENV_EEPROM_IS_ON_I2C 2900 define this, if you have I2C and SPI activated, and your 2901 EEPROM, which holds the environment, is on the I2C bus. 2902 2903 - CONFIG_I2C_ENV_EEPROM_BUS 2904 if you have an Environment on an EEPROM reached over 2905 I2C muxes, you can define here, how to reach this 2906 EEPROM. For example: 2907 2908 #define CONFIG_I2C_ENV_EEPROM_BUS "pca9547:70:d\0" 2909 2910 EEPROM which holds the environment, is reached over 2911 a pca9547 i2c mux with address 0x70, channel 3. 2912 2913- CONFIG_ENV_IS_IN_DATAFLASH: 2914 2915 Define this if you have a DataFlash memory device which you 2916 want to use for the environment. 2917 2918 - CONFIG_ENV_OFFSET: 2919 - CONFIG_ENV_ADDR: 2920 - CONFIG_ENV_SIZE: 2921 2922 These three #defines specify the offset and size of the 2923 environment area within the total memory of your DataFlash placed 2924 at the specified address. 2925 2926- CONFIG_ENV_IS_IN_NAND: 2927 2928 Define this if you have a NAND device which you want to use 2929 for the environment. 2930 2931 - CONFIG_ENV_OFFSET: 2932 - CONFIG_ENV_SIZE: 2933 2934 These two #defines specify the offset and size of the environment 2935 area within the first NAND device. CONFIG_ENV_OFFSET must be 2936 aligned to an erase block boundary. 2937 2938 - CONFIG_ENV_OFFSET_REDUND (optional): 2939 2940 This setting describes a second storage area of CONFIG_ENV_SIZE 2941 size used to hold a redundant copy of the environment data, so 2942 that there is a valid backup copy in case there is a power failure 2943 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be 2944 aligned to an erase block boundary. 2945 2946 - CONFIG_ENV_RANGE (optional): 2947 2948 Specifies the length of the region in which the environment 2949 can be written. This should be a multiple of the NAND device's 2950 block size. Specifying a range with more erase blocks than 2951 are needed to hold CONFIG_ENV_SIZE allows bad blocks within 2952 the range to be avoided. 2953 2954 - CONFIG_ENV_OFFSET_OOB (optional): 2955 2956 Enables support for dynamically retrieving the offset of the 2957 environment from block zero's out-of-band data. The 2958 "nand env.oob" command can be used to record this offset. 2959 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when 2960 using CONFIG_ENV_OFFSET_OOB. 2961 2962- CONFIG_NAND_ENV_DST 2963 2964 Defines address in RAM to which the nand_spl code should copy the 2965 environment. If redundant environment is used, it will be copied to 2966 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE. 2967 2968- CONFIG_SYS_SPI_INIT_OFFSET 2969 2970 Defines offset to the initial SPI buffer area in DPRAM. The 2971 area is used at an early stage (ROM part) if the environment 2972 is configured to reside in the SPI EEPROM: We need a 520 byte 2973 scratch DPRAM area. It is used between the two initialization 2974 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems 2975 to be a good choice since it makes it far enough from the 2976 start of the data area as well as from the stack pointer. 2977 2978Please note that the environment is read-only until the monitor 2979has been relocated to RAM and a RAM copy of the environment has been 2980created; also, when using EEPROM you will have to use getenv_f() 2981until then to read environment variables. 2982 2983The environment is protected by a CRC32 checksum. Before the monitor 2984is relocated into RAM, as a result of a bad CRC you will be working 2985with the compiled-in default environment - *silently*!!! [This is 2986necessary, because the first environment variable we need is the 2987"baudrate" setting for the console - if we have a bad CRC, we don't 2988have any device yet where we could complain.] 2989 2990Note: once the monitor has been relocated, then it will complain if 2991the default environment is used; a new CRC is computed as soon as you 2992use the "saveenv" command to store a valid environment. 2993 2994- CONFIG_SYS_FAULT_ECHO_LINK_DOWN: 2995 Echo the inverted Ethernet link state to the fault LED. 2996 2997 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR 2998 also needs to be defined. 2999 3000- CONFIG_SYS_FAULT_MII_ADDR: 3001 MII address of the PHY to check for the Ethernet link state. 3002 3003- CONFIG_NS16550_MIN_FUNCTIONS: 3004 Define this if you desire to only have use of the NS16550_init 3005 and NS16550_putc functions for the serial driver located at 3006 drivers/serial/ns16550.c. This option is useful for saving 3007 space for already greatly restricted images, including but not 3008 limited to NAND_SPL configurations. 3009 3010Low Level (hardware related) configuration options: 3011--------------------------------------------------- 3012 3013- CONFIG_SYS_CACHELINE_SIZE: 3014 Cache Line Size of the CPU. 3015 3016- CONFIG_SYS_DEFAULT_IMMR: 3017 Default address of the IMMR after system reset. 3018 3019 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU, 3020 and RPXsuper) to be able to adjust the position of 3021 the IMMR register after a reset. 3022 3023- CONFIG_SYS_CCSRBAR_DEFAULT: 3024 Default (power-on reset) physical address of CCSR on Freescale 3025 PowerPC SOCs. 3026 3027- CONFIG_SYS_CCSRBAR: 3028 Virtual address of CCSR. On a 32-bit build, this is typically 3029 the same value as CONFIG_SYS_CCSRBAR_DEFAULT. 3030 3031 CONFIG_SYS_DEFAULT_IMMR must also be set to this value, 3032 for cross-platform code that uses that macro instead. 3033 3034- CONFIG_SYS_CCSRBAR_PHYS: 3035 Physical address of CCSR. CCSR can be relocated to a new 3036 physical address, if desired. In this case, this macro should 3037 be set to that address. Otherwise, it should be set to the 3038 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR 3039 is typically relocated on 36-bit builds. It is recommended 3040 that this macro be defined via the _HIGH and _LOW macros: 3041 3042 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH 3043 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW) 3044 3045- CONFIG_SYS_CCSRBAR_PHYS_HIGH: 3046 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically 3047 either 0 (32-bit build) or 0xF (36-bit build). This macro is 3048 used in assembly code, so it must not contain typecasts or 3049 integer size suffixes (e.g. "ULL"). 3050 3051- CONFIG_SYS_CCSRBAR_PHYS_LOW: 3052 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is 3053 used in assembly code, so it must not contain typecasts or 3054 integer size suffixes (e.g. "ULL"). 3055 3056- CONFIG_SYS_CCSR_DO_NOT_RELOCATE: 3057 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be 3058 forced to a value that ensures that CCSR is not relocated. 3059 3060- Floppy Disk Support: 3061 CONFIG_SYS_FDC_DRIVE_NUMBER 3062 3063 the default drive number (default value 0) 3064 3065 CONFIG_SYS_ISA_IO_STRIDE 3066 3067 defines the spacing between FDC chipset registers 3068 (default value 1) 3069 3070 CONFIG_SYS_ISA_IO_OFFSET 3071 3072 defines the offset of register from address. It 3073 depends on which part of the data bus is connected to 3074 the FDC chipset. (default value 0) 3075 3076 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and 3077 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their 3078 default value. 3079 3080 if CONFIG_SYS_FDC_HW_INIT is defined, then the function 3081 fdc_hw_init() is called at the beginning of the FDC 3082 setup. fdc_hw_init() must be provided by the board 3083 source code. It is used to make hardware dependant 3084 initializations. 3085 3086- CONFIG_IDE_AHB: 3087 Most IDE controllers were designed to be connected with PCI 3088 interface. Only few of them were designed for AHB interface. 3089 When software is doing ATA command and data transfer to 3090 IDE devices through IDE-AHB controller, some additional 3091 registers accessing to these kind of IDE-AHB controller 3092 is requierd. 3093 3094- CONFIG_SYS_IMMR: Physical address of the Internal Memory. 3095 DO NOT CHANGE unless you know exactly what you're 3096 doing! (11-4) [MPC8xx/82xx systems only] 3097 3098- CONFIG_SYS_INIT_RAM_ADDR: 3099 3100 Start address of memory area that can be used for 3101 initial data and stack; please note that this must be 3102 writable memory that is working WITHOUT special 3103 initialization, i. e. you CANNOT use normal RAM which 3104 will become available only after programming the 3105 memory controller and running certain initialization 3106 sequences. 3107 3108 U-Boot uses the following memory types: 3109 - MPC8xx and MPC8260: IMMR (internal memory of the CPU) 3110 - MPC824X: data cache 3111 - PPC4xx: data cache 3112 3113- CONFIG_SYS_GBL_DATA_OFFSET: 3114 3115 Offset of the initial data structure in the memory 3116 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually 3117 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial 3118 data is located at the end of the available space 3119 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE - 3120 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just 3121 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR + 3122 CONFIG_SYS_GBL_DATA_OFFSET) downward. 3123 3124 Note: 3125 On the MPC824X (or other systems that use the data 3126 cache for initial memory) the address chosen for 3127 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must 3128 point to an otherwise UNUSED address space between 3129 the top of RAM and the start of the PCI space. 3130 3131- CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6) 3132 3133- CONFIG_SYS_SYPCR: System Protection Control (11-9) 3134 3135- CONFIG_SYS_TBSCR: Time Base Status and Control (11-26) 3136 3137- CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31) 3138 3139- CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30) 3140 3141- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27) 3142 3143- CONFIG_SYS_OR_TIMING_SDRAM: 3144 SDRAM timing 3145 3146- CONFIG_SYS_MAMR_PTA: 3147 periodic timer for refresh 3148 3149- CONFIG_SYS_DER: Debug Event Register (37-47) 3150 3151- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM, 3152 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP, 3153 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM, 3154 CONFIG_SYS_BR1_PRELIM: 3155 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 3156 3157- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 3158 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM, 3159 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM: 3160 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 3161 3162- CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K, 3163 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL: 3164 Machine Mode Register and Memory Periodic Timer 3165 Prescaler definitions (SDRAM timing) 3166 3167- CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]: 3168 enable I2C microcode relocation patch (MPC8xx); 3169 define relocation offset in DPRAM [DSP2] 3170 3171- CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]: 3172 enable SMC microcode relocation patch (MPC8xx); 3173 define relocation offset in DPRAM [SMC1] 3174 3175- CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]: 3176 enable SPI microcode relocation patch (MPC8xx); 3177 define relocation offset in DPRAM [SCC4] 3178 3179- CONFIG_SYS_USE_OSCCLK: 3180 Use OSCM clock mode on MBX8xx board. Be careful, 3181 wrong setting might damage your board. Read 3182 doc/README.MBX before setting this variable! 3183 3184- CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only) 3185 Offset of the bootmode word in DPRAM used by post 3186 (Power On Self Tests). This definition overrides 3187 #define'd default value in commproc.h resp. 3188 cpm_8260.h. 3189 3190- CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB, 3191 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL, 3192 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS, 3193 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB, 3194 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START, 3195 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL, 3196 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE, 3197 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only) 3198 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set. 3199 3200- CONFIG_PCI_DISABLE_PCIE: 3201 Disable PCI-Express on systems where it is supported but not 3202 required. 3203 3204- CONFIG_SYS_SRIO: 3205 Chip has SRIO or not 3206 3207- CONFIG_SRIO1: 3208 Board has SRIO 1 port available 3209 3210- CONFIG_SRIO2: 3211 Board has SRIO 2 port available 3212 3213- CONFIG_SYS_SRIOn_MEM_VIRT: 3214 Virtual Address of SRIO port 'n' memory region 3215 3216- CONFIG_SYS_SRIOn_MEM_PHYS: 3217 Physical Address of SRIO port 'n' memory region 3218 3219- CONFIG_SYS_SRIOn_MEM_SIZE: 3220 Size of SRIO port 'n' memory region 3221 3222- CONFIG_SYS_NDFC_16 3223 Defined to tell the NDFC that the NAND chip is using a 3224 16 bit bus. 3225 3226- CONFIG_SYS_NDFC_EBC0_CFG 3227 Sets the EBC0_CFG register for the NDFC. If not defined 3228 a default value will be used. 3229 3230- CONFIG_SPD_EEPROM 3231 Get DDR timing information from an I2C EEPROM. Common 3232 with pluggable memory modules such as SODIMMs 3233 3234 SPD_EEPROM_ADDRESS 3235 I2C address of the SPD EEPROM 3236 3237- CONFIG_SYS_SPD_BUS_NUM 3238 If SPD EEPROM is on an I2C bus other than the first 3239 one, specify here. Note that the value must resolve 3240 to something your driver can deal with. 3241 3242- CONFIG_SYS_DDR_RAW_TIMING 3243 Get DDR timing information from other than SPD. Common with 3244 soldered DDR chips onboard without SPD. DDR raw timing 3245 parameters are extracted from datasheet and hard-coded into 3246 header files or board specific files. 3247 3248- CONFIG_FSL_DDR_INTERACTIVE 3249 Enable interactive DDR debugging. See doc/README.fsl-ddr. 3250 3251- CONFIG_SYS_83XX_DDR_USES_CS0 3252 Only for 83xx systems. If specified, then DDR should 3253 be configured using CS0 and CS1 instead of CS2 and CS3. 3254 3255- CONFIG_ETHER_ON_FEC[12] 3256 Define to enable FEC[12] on a 8xx series processor. 3257 3258- CONFIG_FEC[12]_PHY 3259 Define to the hardcoded PHY address which corresponds 3260 to the given FEC; i. e. 3261 #define CONFIG_FEC1_PHY 4 3262 means that the PHY with address 4 is connected to FEC1 3263 3264 When set to -1, means to probe for first available. 3265 3266- CONFIG_FEC[12]_PHY_NORXERR 3267 The PHY does not have a RXERR line (RMII only). 3268 (so program the FEC to ignore it). 3269 3270- CONFIG_RMII 3271 Enable RMII mode for all FECs. 3272 Note that this is a global option, we can't 3273 have one FEC in standard MII mode and another in RMII mode. 3274 3275- CONFIG_CRC32_VERIFY 3276 Add a verify option to the crc32 command. 3277 The syntax is: 3278 3279 => crc32 -v <address> <count> <crc32> 3280 3281 Where address/count indicate a memory area 3282 and crc32 is the correct crc32 which the 3283 area should have. 3284 3285- CONFIG_LOOPW 3286 Add the "loopw" memory command. This only takes effect if 3287 the memory commands are activated globally (CONFIG_CMD_MEM). 3288 3289- CONFIG_MX_CYCLIC 3290 Add the "mdc" and "mwc" memory commands. These are cyclic 3291 "md/mw" commands. 3292 Examples: 3293 3294 => mdc.b 10 4 500 3295 This command will print 4 bytes (10,11,12,13) each 500 ms. 3296 3297 => mwc.l 100 12345678 10 3298 This command will write 12345678 to address 100 all 10 ms. 3299 3300 This only takes effect if the memory commands are activated 3301 globally (CONFIG_CMD_MEM). 3302 3303- CONFIG_SKIP_LOWLEVEL_INIT 3304 [ARM, NDS32, MIPS only] If this variable is defined, then certain 3305 low level initializations (like setting up the memory 3306 controller) are omitted and/or U-Boot does not 3307 relocate itself into RAM. 3308 3309 Normally this variable MUST NOT be defined. The only 3310 exception is when U-Boot is loaded (to RAM) by some 3311 other boot loader or by a debugger which performs 3312 these initializations itself. 3313 3314- CONFIG_SPL_BUILD 3315 Modifies the behaviour of start.S when compiling a loader 3316 that is executed before the actual U-Boot. E.g. when 3317 compiling a NAND SPL. 3318 3319- CONFIG_SYS_NAND_HW_ECC_OOBFIRST 3320 define this, if you want to read first the oob data 3321 and then the data. This is used for example on 3322 davinci plattforms. 3323 3324- CONFIG_USE_ARCH_MEMCPY 3325 CONFIG_USE_ARCH_MEMSET 3326 If these options are used a optimized version of memcpy/memset will 3327 be used if available. These functions may be faster under some 3328 conditions but may increase the binary size. 3329 3330Freescale QE/FMAN Firmware Support: 3331----------------------------------- 3332 3333The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the 3334loading of "firmware", which is encoded in the QE firmware binary format. 3335This firmware often needs to be loaded during U-Boot booting, so macros 3336are used to identify the storage device (NOR flash, SPI, etc) and the address 3337within that device. 3338 3339- CONFIG_SYS_QE_FMAN_FW_ADDR 3340 The address in the storage device where the firmware is located. The 3341 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 3342 is also specified. 3343 3344- CONFIG_SYS_QE_FMAN_FW_LENGTH 3345 The maximum possible size of the firmware. The firmware binary format 3346 has a field that specifies the actual size of the firmware, but it 3347 might not be possible to read any part of the firmware unless some 3348 local storage is allocated to hold the entire firmware first. 3349 3350- CONFIG_SYS_QE_FMAN_FW_IN_NOR 3351 Specifies that QE/FMAN firmware is located in NOR flash, mapped as 3352 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the 3353 virtual address in NOR flash. 3354 3355- CONFIG_SYS_QE_FMAN_FW_IN_NAND 3356 Specifies that QE/FMAN firmware is located in NAND flash. 3357 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash. 3358 3359- CONFIG_SYS_QE_FMAN_FW_IN_MMC 3360 Specifies that QE/FMAN firmware is located on the primary SD/MMC 3361 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 3362 3363- CONFIG_SYS_QE_FMAN_FW_IN_SPIFLASH 3364 Specifies that QE/FMAN firmware is located on the primary SPI 3365 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 3366 3367 3368Building the Software: 3369====================== 3370 3371Building U-Boot has been tested in several native build environments 3372and in many different cross environments. Of course we cannot support 3373all possibly existing versions of cross development tools in all 3374(potentially obsolete) versions. In case of tool chain problems we 3375recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK) 3376which is extensively used to build and test U-Boot. 3377 3378If you are not using a native environment, it is assumed that you 3379have GNU cross compiling tools available in your path. In this case, 3380you must set the environment variable CROSS_COMPILE in your shell. 3381Note that no changes to the Makefile or any other source files are 3382necessary. For example using the ELDK on a 4xx CPU, please enter: 3383 3384 $ CROSS_COMPILE=ppc_4xx- 3385 $ export CROSS_COMPILE 3386 3387Note: If you wish to generate Windows versions of the utilities in 3388 the tools directory you can use the MinGW toolchain 3389 (http://www.mingw.org). Set your HOST tools to the MinGW 3390 toolchain and execute 'make tools'. For example: 3391 3392 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools 3393 3394 Binaries such as tools/mkimage.exe will be created which can 3395 be executed on computers running Windows. 3396 3397U-Boot is intended to be simple to build. After installing the 3398sources you must configure U-Boot for one specific board type. This 3399is done by typing: 3400 3401 make NAME_config 3402 3403where "NAME_config" is the name of one of the existing configu- 3404rations; see the main Makefile for supported names. 3405 3406Note: for some board special configuration names may exist; check if 3407 additional information is available from the board vendor; for 3408 instance, the TQM823L systems are available without (standard) 3409 or with LCD support. You can select such additional "features" 3410 when choosing the configuration, i. e. 3411 3412 make TQM823L_config 3413 - will configure for a plain TQM823L, i. e. no LCD support 3414 3415 make TQM823L_LCD_config 3416 - will configure for a TQM823L with U-Boot console on LCD 3417 3418 etc. 3419 3420 3421Finally, type "make all", and you should get some working U-Boot 3422images ready for download to / installation on your system: 3423 3424- "u-boot.bin" is a raw binary image 3425- "u-boot" is an image in ELF binary format 3426- "u-boot.srec" is in Motorola S-Record format 3427 3428By default the build is performed locally and the objects are saved 3429in the source directory. One of the two methods can be used to change 3430this behavior and build U-Boot to some external directory: 3431 34321. Add O= to the make command line invocations: 3433 3434 make O=/tmp/build distclean 3435 make O=/tmp/build NAME_config 3436 make O=/tmp/build all 3437 34382. Set environment variable BUILD_DIR to point to the desired location: 3439 3440 export BUILD_DIR=/tmp/build 3441 make distclean 3442 make NAME_config 3443 make all 3444 3445Note that the command line "O=" setting overrides the BUILD_DIR environment 3446variable. 3447 3448 3449Please be aware that the Makefiles assume you are using GNU make, so 3450for instance on NetBSD you might need to use "gmake" instead of 3451native "make". 3452 3453 3454If the system board that you have is not listed, then you will need 3455to port U-Boot to your hardware platform. To do this, follow these 3456steps: 3457 34581. Add a new configuration option for your board to the toplevel 3459 "Makefile" and to the "MAKEALL" script, using the existing 3460 entries as examples. Note that here and at many other places 3461 boards and other names are listed in alphabetical sort order. Please 3462 keep this order. 34632. Create a new directory to hold your board specific code. Add any 3464 files you need. In your board directory, you will need at least 3465 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds". 34663. Create a new configuration file "include/configs/<board>.h" for 3467 your board 34683. If you're porting U-Boot to a new CPU, then also create a new 3469 directory to hold your CPU specific code. Add any files you need. 34704. Run "make <board>_config" with your new name. 34715. Type "make", and you should get a working "u-boot.srec" file 3472 to be installed on your target system. 34736. Debug and solve any problems that might arise. 3474 [Of course, this last step is much harder than it sounds.] 3475 3476 3477Testing of U-Boot Modifications, Ports to New Hardware, etc.: 3478============================================================== 3479 3480If you have modified U-Boot sources (for instance added a new board 3481or support for new devices, a new CPU, etc.) you are expected to 3482provide feedback to the other developers. The feedback normally takes 3483the form of a "patch", i. e. a context diff against a certain (latest 3484official or latest in the git repository) version of U-Boot sources. 3485 3486But before you submit such a patch, please verify that your modifi- 3487cation did not break existing code. At least make sure that *ALL* of 3488the supported boards compile WITHOUT ANY compiler warnings. To do so, 3489just run the "MAKEALL" script, which will configure and build U-Boot 3490for ALL supported system. Be warned, this will take a while. You can 3491select which (cross) compiler to use by passing a `CROSS_COMPILE' 3492environment variable to the script, i. e. to use the ELDK cross tools 3493you can type 3494 3495 CROSS_COMPILE=ppc_8xx- MAKEALL 3496 3497or to build on a native PowerPC system you can type 3498 3499 CROSS_COMPILE=' ' MAKEALL 3500 3501When using the MAKEALL script, the default behaviour is to build 3502U-Boot in the source directory. This location can be changed by 3503setting the BUILD_DIR environment variable. Also, for each target 3504built, the MAKEALL script saves two log files (<target>.ERR and 3505<target>.MAKEALL) in the <source dir>/LOG directory. This default 3506location can be changed by setting the MAKEALL_LOGDIR environment 3507variable. For example: 3508 3509 export BUILD_DIR=/tmp/build 3510 export MAKEALL_LOGDIR=/tmp/log 3511 CROSS_COMPILE=ppc_8xx- MAKEALL 3512 3513With the above settings build objects are saved in the /tmp/build, 3514log files are saved in the /tmp/log and the source tree remains clean 3515during the whole build process. 3516 3517 3518See also "U-Boot Porting Guide" below. 3519 3520 3521Monitor Commands - Overview: 3522============================ 3523 3524go - start application at address 'addr' 3525run - run commands in an environment variable 3526bootm - boot application image from memory 3527bootp - boot image via network using BootP/TFTP protocol 3528tftpboot- boot image via network using TFTP protocol 3529 and env variables "ipaddr" and "serverip" 3530 (and eventually "gatewayip") 3531tftpput - upload a file via network using TFTP protocol 3532rarpboot- boot image via network using RARP/TFTP protocol 3533diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 3534loads - load S-Record file over serial line 3535loadb - load binary file over serial line (kermit mode) 3536md - memory display 3537mm - memory modify (auto-incrementing) 3538nm - memory modify (constant address) 3539mw - memory write (fill) 3540cp - memory copy 3541cmp - memory compare 3542crc32 - checksum calculation 3543i2c - I2C sub-system 3544sspi - SPI utility commands 3545base - print or set address offset 3546printenv- print environment variables 3547setenv - set environment variables 3548saveenv - save environment variables to persistent storage 3549protect - enable or disable FLASH write protection 3550erase - erase FLASH memory 3551flinfo - print FLASH memory information 3552bdinfo - print Board Info structure 3553iminfo - print header information for application image 3554coninfo - print console devices and informations 3555ide - IDE sub-system 3556loop - infinite loop on address range 3557loopw - infinite write loop on address range 3558mtest - simple RAM test 3559icache - enable or disable instruction cache 3560dcache - enable or disable data cache 3561reset - Perform RESET of the CPU 3562echo - echo args to console 3563version - print monitor version 3564help - print online help 3565? - alias for 'help' 3566 3567 3568Monitor Commands - Detailed Description: 3569======================================== 3570 3571TODO. 3572 3573For now: just type "help <command>". 3574 3575 3576Environment Variables: 3577====================== 3578 3579U-Boot supports user configuration using Environment Variables which 3580can be made persistent by saving to Flash memory. 3581 3582Environment Variables are set using "setenv", printed using 3583"printenv", and saved to Flash using "saveenv". Using "setenv" 3584without a value can be used to delete a variable from the 3585environment. As long as you don't save the environment you are 3586working with an in-memory copy. In case the Flash area containing the 3587environment is erased by accident, a default environment is provided. 3588 3589Some configuration options can be set using Environment Variables. 3590 3591List of environment variables (most likely not complete): 3592 3593 baudrate - see CONFIG_BAUDRATE 3594 3595 bootdelay - see CONFIG_BOOTDELAY 3596 3597 bootcmd - see CONFIG_BOOTCOMMAND 3598 3599 bootargs - Boot arguments when booting an RTOS image 3600 3601 bootfile - Name of the image to load with TFTP 3602 3603 bootm_low - Memory range available for image processing in the bootm 3604 command can be restricted. This variable is given as 3605 a hexadecimal number and defines lowest address allowed 3606 for use by the bootm command. See also "bootm_size" 3607 environment variable. Address defined by "bootm_low" is 3608 also the base of the initial memory mapping for the Linux 3609 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and 3610 bootm_mapsize. 3611 3612 bootm_mapsize - Size of the initial memory mapping for the Linux kernel. 3613 This variable is given as a hexadecimal number and it 3614 defines the size of the memory region starting at base 3615 address bootm_low that is accessible by the Linux kernel 3616 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used 3617 as the default value if it is defined, and bootm_size is 3618 used otherwise. 3619 3620 bootm_size - Memory range available for image processing in the bootm 3621 command can be restricted. This variable is given as 3622 a hexadecimal number and defines the size of the region 3623 allowed for use by the bootm command. See also "bootm_low" 3624 environment variable. 3625 3626 updatefile - Location of the software update file on a TFTP server, used 3627 by the automatic software update feature. Please refer to 3628 documentation in doc/README.update for more details. 3629 3630 autoload - if set to "no" (any string beginning with 'n'), 3631 "bootp" will just load perform a lookup of the 3632 configuration from the BOOTP server, but not try to 3633 load any image using TFTP 3634 3635 autostart - if set to "yes", an image loaded using the "bootp", 3636 "rarpboot", "tftpboot" or "diskboot" commands will 3637 be automatically started (by internally calling 3638 "bootm") 3639 3640 If set to "no", a standalone image passed to the 3641 "bootm" command will be copied to the load address 3642 (and eventually uncompressed), but NOT be started. 3643 This can be used to load and uncompress arbitrary 3644 data. 3645 3646 fdt_high - if set this restricts the maximum address that the 3647 flattened device tree will be copied into upon boot. 3648 If this is set to the special value 0xFFFFFFFF then 3649 the fdt will not be copied at all on boot. For this 3650 to work it must reside in writable memory, have 3651 sufficient padding on the end of it for u-boot to 3652 add the information it needs into it, and the memory 3653 must be accessible by the kernel. 3654 3655 fdtcontroladdr- if set this is the address of the control flattened 3656 device tree used by U-Boot when CONFIG_OF_CONTROL is 3657 defined. 3658 3659 i2cfast - (PPC405GP|PPC405EP only) 3660 if set to 'y' configures Linux I2C driver for fast 3661 mode (400kHZ). This environment variable is used in 3662 initialization code. So, for changes to be effective 3663 it must be saved and board must be reset. 3664 3665 initrd_high - restrict positioning of initrd images: 3666 If this variable is not set, initrd images will be 3667 copied to the highest possible address in RAM; this 3668 is usually what you want since it allows for 3669 maximum initrd size. If for some reason you want to 3670 make sure that the initrd image is loaded below the 3671 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment 3672 variable to a value of "no" or "off" or "0". 3673 Alternatively, you can set it to a maximum upper 3674 address to use (U-Boot will still check that it 3675 does not overwrite the U-Boot stack and data). 3676 3677 For instance, when you have a system with 16 MB 3678 RAM, and want to reserve 4 MB from use by Linux, 3679 you can do this by adding "mem=12M" to the value of 3680 the "bootargs" variable. However, now you must make 3681 sure that the initrd image is placed in the first 3682 12 MB as well - this can be done with 3683 3684 setenv initrd_high 00c00000 3685 3686 If you set initrd_high to 0xFFFFFFFF, this is an 3687 indication to U-Boot that all addresses are legal 3688 for the Linux kernel, including addresses in flash 3689 memory. In this case U-Boot will NOT COPY the 3690 ramdisk at all. This may be useful to reduce the 3691 boot time on your system, but requires that this 3692 feature is supported by your Linux kernel. 3693 3694 ipaddr - IP address; needed for tftpboot command 3695 3696 loadaddr - Default load address for commands like "bootp", 3697 "rarpboot", "tftpboot", "loadb" or "diskboot" 3698 3699 loads_echo - see CONFIG_LOADS_ECHO 3700 3701 serverip - TFTP server IP address; needed for tftpboot command 3702 3703 bootretry - see CONFIG_BOOT_RETRY_TIME 3704 3705 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 3706 3707 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 3708 3709 ethprime - controls which interface is used first. 3710 3711 ethact - controls which interface is currently active. 3712 For example you can do the following 3713 3714 => setenv ethact FEC 3715 => ping 192.168.0.1 # traffic sent on FEC 3716 => setenv ethact SCC 3717 => ping 10.0.0.1 # traffic sent on SCC 3718 3719 ethrotate - When set to "no" U-Boot does not go through all 3720 available network interfaces. 3721 It just stays at the currently selected interface. 3722 3723 netretry - When set to "no" each network operation will 3724 either succeed or fail without retrying. 3725 When set to "once" the network operation will 3726 fail when all the available network interfaces 3727 are tried once without success. 3728 Useful on scripts which control the retry operation 3729 themselves. 3730 3731 npe_ucode - set load address for the NPE microcode 3732 3733 tftpsrcport - If this is set, the value is used for TFTP's 3734 UDP source port. 3735 3736 tftpdstport - If this is set, the value is used for TFTP's UDP 3737 destination port instead of the Well Know Port 69. 3738 3739 tftpblocksize - Block size to use for TFTP transfers; if not set, 3740 we use the TFTP server's default block size 3741 3742 tftptimeout - Retransmission timeout for TFTP packets (in milli- 3743 seconds, minimum value is 1000 = 1 second). Defines 3744 when a packet is considered to be lost so it has to 3745 be retransmitted. The default is 5000 = 5 seconds. 3746 Lowering this value may make downloads succeed 3747 faster in networks with high packet loss rates or 3748 with unreliable TFTP servers. 3749 3750 vlan - When set to a value < 4095 the traffic over 3751 Ethernet is encapsulated/received over 802.1q 3752 VLAN tagged frames. 3753 3754The following image location variables contain the location of images 3755used in booting. The "Image" column gives the role of the image and is 3756not an environment variable name. The other columns are environment 3757variable names. "File Name" gives the name of the file on a TFTP 3758server, "RAM Address" gives the location in RAM the image will be 3759loaded to, and "Flash Location" gives the image's address in NOR 3760flash or offset in NAND flash. 3761 3762*Note* - these variables don't have to be defined for all boards, some 3763boards currenlty use other variables for these purposes, and some 3764boards use these variables for other purposes. 3765 3766Image File Name RAM Address Flash Location 3767----- --------- ----------- -------------- 3768u-boot u-boot u-boot_addr_r u-boot_addr 3769Linux kernel bootfile kernel_addr_r kernel_addr 3770device tree blob fdtfile fdt_addr_r fdt_addr 3771ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr 3772 3773The following environment variables may be used and automatically 3774updated by the network boot commands ("bootp" and "rarpboot"), 3775depending the information provided by your boot server: 3776 3777 bootfile - see above 3778 dnsip - IP address of your Domain Name Server 3779 dnsip2 - IP address of your secondary Domain Name Server 3780 gatewayip - IP address of the Gateway (Router) to use 3781 hostname - Target hostname 3782 ipaddr - see above 3783 netmask - Subnet Mask 3784 rootpath - Pathname of the root filesystem on the NFS server 3785 serverip - see above 3786 3787 3788There are two special Environment Variables: 3789 3790 serial# - contains hardware identification information such 3791 as type string and/or serial number 3792 ethaddr - Ethernet address 3793 3794These variables can be set only once (usually during manufacturing of 3795the board). U-Boot refuses to delete or overwrite these variables 3796once they have been set once. 3797 3798 3799Further special Environment Variables: 3800 3801 ver - Contains the U-Boot version string as printed 3802 with the "version" command. This variable is 3803 readonly (see CONFIG_VERSION_VARIABLE). 3804 3805 3806Please note that changes to some configuration parameters may take 3807only effect after the next boot (yes, that's just like Windoze :-). 3808 3809 3810Command Line Parsing: 3811===================== 3812 3813There are two different command line parsers available with U-Boot: 3814the old "simple" one, and the much more powerful "hush" shell: 3815 3816Old, simple command line parser: 3817-------------------------------- 3818 3819- supports environment variables (through setenv / saveenv commands) 3820- several commands on one line, separated by ';' 3821- variable substitution using "... ${name} ..." syntax 3822- special characters ('$', ';') can be escaped by prefixing with '\', 3823 for example: 3824 setenv bootcmd bootm \${address} 3825- You can also escape text by enclosing in single apostrophes, for example: 3826 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off' 3827 3828Hush shell: 3829----------- 3830 3831- similar to Bourne shell, with control structures like 3832 if...then...else...fi, for...do...done; while...do...done, 3833 until...do...done, ... 3834- supports environment ("global") variables (through setenv / saveenv 3835 commands) and local shell variables (through standard shell syntax 3836 "name=value"); only environment variables can be used with "run" 3837 command 3838 3839General rules: 3840-------------- 3841 3842(1) If a command line (or an environment variable executed by a "run" 3843 command) contains several commands separated by semicolon, and 3844 one of these commands fails, then the remaining commands will be 3845 executed anyway. 3846 3847(2) If you execute several variables with one call to run (i. e. 3848 calling run with a list of variables as arguments), any failing 3849 command will cause "run" to terminate, i. e. the remaining 3850 variables are not executed. 3851 3852Note for Redundant Ethernet Interfaces: 3853======================================= 3854 3855Some boards come with redundant Ethernet interfaces; U-Boot supports 3856such configurations and is capable of automatic selection of a 3857"working" interface when needed. MAC assignment works as follows: 3858 3859Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 3860MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 3861"eth1addr" (=>eth1), "eth2addr", ... 3862 3863If the network interface stores some valid MAC address (for instance 3864in SROM), this is used as default address if there is NO correspon- 3865ding setting in the environment; if the corresponding environment 3866variable is set, this overrides the settings in the card; that means: 3867 3868o If the SROM has a valid MAC address, and there is no address in the 3869 environment, the SROM's address is used. 3870 3871o If there is no valid address in the SROM, and a definition in the 3872 environment exists, then the value from the environment variable is 3873 used. 3874 3875o If both the SROM and the environment contain a MAC address, and 3876 both addresses are the same, this MAC address is used. 3877 3878o If both the SROM and the environment contain a MAC address, and the 3879 addresses differ, the value from the environment is used and a 3880 warning is printed. 3881 3882o If neither SROM nor the environment contain a MAC address, an error 3883 is raised. 3884 3885If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses 3886will be programmed into hardware as part of the initialization process. This 3887may be skipped by setting the appropriate 'ethmacskip' environment variable. 3888The naming convention is as follows: 3889"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc. 3890 3891Image Formats: 3892============== 3893 3894U-Boot is capable of booting (and performing other auxiliary operations on) 3895images in two formats: 3896 3897New uImage format (FIT) 3898----------------------- 3899 3900Flexible and powerful format based on Flattened Image Tree -- FIT (similar 3901to Flattened Device Tree). It allows the use of images with multiple 3902components (several kernels, ramdisks, etc.), with contents protected by 3903SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory. 3904 3905 3906Old uImage format 3907----------------- 3908 3909Old image format is based on binary files which can be basically anything, 3910preceded by a special header; see the definitions in include/image.h for 3911details; basically, the header defines the following image properties: 3912 3913* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 3914 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 3915 LynxOS, pSOS, QNX, RTEMS, INTEGRITY; 3916 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS, 3917 INTEGRITY). 3918* Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86, 3919 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 3920 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC). 3921* Compression Type (uncompressed, gzip, bzip2) 3922* Load Address 3923* Entry Point 3924* Image Name 3925* Image Timestamp 3926 3927The header is marked by a special Magic Number, and both the header 3928and the data portions of the image are secured against corruption by 3929CRC32 checksums. 3930 3931 3932Linux Support: 3933============== 3934 3935Although U-Boot should support any OS or standalone application 3936easily, the main focus has always been on Linux during the design of 3937U-Boot. 3938 3939U-Boot includes many features that so far have been part of some 3940special "boot loader" code within the Linux kernel. Also, any 3941"initrd" images to be used are no longer part of one big Linux image; 3942instead, kernel and "initrd" are separate images. This implementation 3943serves several purposes: 3944 3945- the same features can be used for other OS or standalone 3946 applications (for instance: using compressed images to reduce the 3947 Flash memory footprint) 3948 3949- it becomes much easier to port new Linux kernel versions because 3950 lots of low-level, hardware dependent stuff are done by U-Boot 3951 3952- the same Linux kernel image can now be used with different "initrd" 3953 images; of course this also means that different kernel images can 3954 be run with the same "initrd". This makes testing easier (you don't 3955 have to build a new "zImage.initrd" Linux image when you just 3956 change a file in your "initrd"). Also, a field-upgrade of the 3957 software is easier now. 3958 3959 3960Linux HOWTO: 3961============ 3962 3963Porting Linux to U-Boot based systems: 3964--------------------------------------- 3965 3966U-Boot cannot save you from doing all the necessary modifications to 3967configure the Linux device drivers for use with your target hardware 3968(no, we don't intend to provide a full virtual machine interface to 3969Linux :-). 3970 3971But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot). 3972 3973Just make sure your machine specific header file (for instance 3974include/asm-ppc/tqm8xx.h) includes the same definition of the Board 3975Information structure as we define in include/asm-<arch>/u-boot.h, 3976and make sure that your definition of IMAP_ADDR uses the same value 3977as your U-Boot configuration in CONFIG_SYS_IMMR. 3978 3979 3980Configuring the Linux kernel: 3981----------------------------- 3982 3983No specific requirements for U-Boot. Make sure you have some root 3984device (initial ramdisk, NFS) for your target system. 3985 3986 3987Building a Linux Image: 3988----------------------- 3989 3990With U-Boot, "normal" build targets like "zImage" or "bzImage" are 3991not used. If you use recent kernel source, a new build target 3992"uImage" will exist which automatically builds an image usable by 3993U-Boot. Most older kernels also have support for a "pImage" target, 3994which was introduced for our predecessor project PPCBoot and uses a 3995100% compatible format. 3996 3997Example: 3998 3999 make TQM850L_config 4000 make oldconfig 4001 make dep 4002 make uImage 4003 4004The "uImage" build target uses a special tool (in 'tools/mkimage') to 4005encapsulate a compressed Linux kernel image with header information, 4006CRC32 checksum etc. for use with U-Boot. This is what we are doing: 4007 4008* build a standard "vmlinux" kernel image (in ELF binary format): 4009 4010* convert the kernel into a raw binary image: 4011 4012 ${CROSS_COMPILE}-objcopy -O binary \ 4013 -R .note -R .comment \ 4014 -S vmlinux linux.bin 4015 4016* compress the binary image: 4017 4018 gzip -9 linux.bin 4019 4020* package compressed binary image for U-Boot: 4021 4022 mkimage -A ppc -O linux -T kernel -C gzip \ 4023 -a 0 -e 0 -n "Linux Kernel Image" \ 4024 -d linux.bin.gz uImage 4025 4026 4027The "mkimage" tool can also be used to create ramdisk images for use 4028with U-Boot, either separated from the Linux kernel image, or 4029combined into one file. "mkimage" encapsulates the images with a 64 4030byte header containing information about target architecture, 4031operating system, image type, compression method, entry points, time 4032stamp, CRC32 checksums, etc. 4033 4034"mkimage" can be called in two ways: to verify existing images and 4035print the header information, or to build new images. 4036 4037In the first form (with "-l" option) mkimage lists the information 4038contained in the header of an existing U-Boot image; this includes 4039checksum verification: 4040 4041 tools/mkimage -l image 4042 -l ==> list image header information 4043 4044The second form (with "-d" option) is used to build a U-Boot image 4045from a "data file" which is used as image payload: 4046 4047 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 4048 -n name -d data_file image 4049 -A ==> set architecture to 'arch' 4050 -O ==> set operating system to 'os' 4051 -T ==> set image type to 'type' 4052 -C ==> set compression type 'comp' 4053 -a ==> set load address to 'addr' (hex) 4054 -e ==> set entry point to 'ep' (hex) 4055 -n ==> set image name to 'name' 4056 -d ==> use image data from 'datafile' 4057 4058Right now, all Linux kernels for PowerPC systems use the same load 4059address (0x00000000), but the entry point address depends on the 4060kernel version: 4061 4062- 2.2.x kernels have the entry point at 0x0000000C, 4063- 2.3.x and later kernels have the entry point at 0x00000000. 4064 4065So a typical call to build a U-Boot image would read: 4066 4067 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 4068 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 4069 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \ 4070 > examples/uImage.TQM850L 4071 Image Name: 2.4.4 kernel for TQM850L 4072 Created: Wed Jul 19 02:34:59 2000 4073 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4074 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 4075 Load Address: 0x00000000 4076 Entry Point: 0x00000000 4077 4078To verify the contents of the image (or check for corruption): 4079 4080 -> tools/mkimage -l examples/uImage.TQM850L 4081 Image Name: 2.4.4 kernel for TQM850L 4082 Created: Wed Jul 19 02:34:59 2000 4083 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4084 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 4085 Load Address: 0x00000000 4086 Entry Point: 0x00000000 4087 4088NOTE: for embedded systems where boot time is critical you can trade 4089speed for memory and install an UNCOMPRESSED image instead: this 4090needs more space in Flash, but boots much faster since it does not 4091need to be uncompressed: 4092 4093 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz 4094 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 4095 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 4096 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \ 4097 > examples/uImage.TQM850L-uncompressed 4098 Image Name: 2.4.4 kernel for TQM850L 4099 Created: Wed Jul 19 02:34:59 2000 4100 Image Type: PowerPC Linux Kernel Image (uncompressed) 4101 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 4102 Load Address: 0x00000000 4103 Entry Point: 0x00000000 4104 4105 4106Similar you can build U-Boot images from a 'ramdisk.image.gz' file 4107when your kernel is intended to use an initial ramdisk: 4108 4109 -> tools/mkimage -n 'Simple Ramdisk Image' \ 4110 > -A ppc -O linux -T ramdisk -C gzip \ 4111 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 4112 Image Name: Simple Ramdisk Image 4113 Created: Wed Jan 12 14:01:50 2000 4114 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 4115 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 4116 Load Address: 0x00000000 4117 Entry Point: 0x00000000 4118 4119 4120Installing a Linux Image: 4121------------------------- 4122 4123To downloading a U-Boot image over the serial (console) interface, 4124you must convert the image to S-Record format: 4125 4126 objcopy -I binary -O srec examples/image examples/image.srec 4127 4128The 'objcopy' does not understand the information in the U-Boot 4129image header, so the resulting S-Record file will be relative to 4130address 0x00000000. To load it to a given address, you need to 4131specify the target address as 'offset' parameter with the 'loads' 4132command. 4133 4134Example: install the image to address 0x40100000 (which on the 4135TQM8xxL is in the first Flash bank): 4136 4137 => erase 40100000 401FFFFF 4138 4139 .......... done 4140 Erased 8 sectors 4141 4142 => loads 40100000 4143 ## Ready for S-Record download ... 4144 ~>examples/image.srec 4145 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 4146 ... 4147 15989 15990 15991 15992 4148 [file transfer complete] 4149 [connected] 4150 ## Start Addr = 0x00000000 4151 4152 4153You can check the success of the download using the 'iminfo' command; 4154this includes a checksum verification so you can be sure no data 4155corruption happened: 4156 4157 => imi 40100000 4158 4159 ## Checking Image at 40100000 ... 4160 Image Name: 2.2.13 for initrd on TQM850L 4161 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4162 Data Size: 335725 Bytes = 327 kB = 0 MB 4163 Load Address: 00000000 4164 Entry Point: 0000000c 4165 Verifying Checksum ... OK 4166 4167 4168Boot Linux: 4169----------- 4170 4171The "bootm" command is used to boot an application that is stored in 4172memory (RAM or Flash). In case of a Linux kernel image, the contents 4173of the "bootargs" environment variable is passed to the kernel as 4174parameters. You can check and modify this variable using the 4175"printenv" and "setenv" commands: 4176 4177 4178 => printenv bootargs 4179 bootargs=root=/dev/ram 4180 4181 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 4182 4183 => printenv bootargs 4184 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 4185 4186 => bootm 40020000 4187 ## Booting Linux kernel at 40020000 ... 4188 Image Name: 2.2.13 for NFS on TQM850L 4189 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4190 Data Size: 381681 Bytes = 372 kB = 0 MB 4191 Load Address: 00000000 4192 Entry Point: 0000000c 4193 Verifying Checksum ... OK 4194 Uncompressing Kernel Image ... OK 4195 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 4196 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 4197 time_init: decrementer frequency = 187500000/60 4198 Calibrating delay loop... 49.77 BogoMIPS 4199 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 4200 ... 4201 4202If you want to boot a Linux kernel with initial RAM disk, you pass 4203the memory addresses of both the kernel and the initrd image (PPBCOOT 4204format!) to the "bootm" command: 4205 4206 => imi 40100000 40200000 4207 4208 ## Checking Image at 40100000 ... 4209 Image Name: 2.2.13 for initrd on TQM850L 4210 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4211 Data Size: 335725 Bytes = 327 kB = 0 MB 4212 Load Address: 00000000 4213 Entry Point: 0000000c 4214 Verifying Checksum ... OK 4215 4216 ## Checking Image at 40200000 ... 4217 Image Name: Simple Ramdisk Image 4218 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 4219 Data Size: 566530 Bytes = 553 kB = 0 MB 4220 Load Address: 00000000 4221 Entry Point: 00000000 4222 Verifying Checksum ... OK 4223 4224 => bootm 40100000 40200000 4225 ## Booting Linux kernel at 40100000 ... 4226 Image Name: 2.2.13 for initrd on TQM850L 4227 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4228 Data Size: 335725 Bytes = 327 kB = 0 MB 4229 Load Address: 00000000 4230 Entry Point: 0000000c 4231 Verifying Checksum ... OK 4232 Uncompressing Kernel Image ... OK 4233 ## Loading RAMDisk Image at 40200000 ... 4234 Image Name: Simple Ramdisk Image 4235 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 4236 Data Size: 566530 Bytes = 553 kB = 0 MB 4237 Load Address: 00000000 4238 Entry Point: 00000000 4239 Verifying Checksum ... OK 4240 Loading Ramdisk ... OK 4241 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 4242 Boot arguments: root=/dev/ram 4243 time_init: decrementer frequency = 187500000/60 4244 Calibrating delay loop... 49.77 BogoMIPS 4245 ... 4246 RAMDISK: Compressed image found at block 0 4247 VFS: Mounted root (ext2 filesystem). 4248 4249 bash# 4250 4251Boot Linux and pass a flat device tree: 4252----------- 4253 4254First, U-Boot must be compiled with the appropriate defines. See the section 4255titled "Linux Kernel Interface" above for a more in depth explanation. The 4256following is an example of how to start a kernel and pass an updated 4257flat device tree: 4258 4259=> print oftaddr 4260oftaddr=0x300000 4261=> print oft 4262oft=oftrees/mpc8540ads.dtb 4263=> tftp $oftaddr $oft 4264Speed: 1000, full duplex 4265Using TSEC0 device 4266TFTP from server 192.168.1.1; our IP address is 192.168.1.101 4267Filename 'oftrees/mpc8540ads.dtb'. 4268Load address: 0x300000 4269Loading: # 4270done 4271Bytes transferred = 4106 (100a hex) 4272=> tftp $loadaddr $bootfile 4273Speed: 1000, full duplex 4274Using TSEC0 device 4275TFTP from server 192.168.1.1; our IP address is 192.168.1.2 4276Filename 'uImage'. 4277Load address: 0x200000 4278Loading:############ 4279done 4280Bytes transferred = 1029407 (fb51f hex) 4281=> print loadaddr 4282loadaddr=200000 4283=> print oftaddr 4284oftaddr=0x300000 4285=> bootm $loadaddr - $oftaddr 4286## Booting image at 00200000 ... 4287 Image Name: Linux-2.6.17-dirty 4288 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4289 Data Size: 1029343 Bytes = 1005.2 kB 4290 Load Address: 00000000 4291 Entry Point: 00000000 4292 Verifying Checksum ... OK 4293 Uncompressing Kernel Image ... OK 4294Booting using flat device tree at 0x300000 4295Using MPC85xx ADS machine description 4296Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb 4297[snip] 4298 4299 4300More About U-Boot Image Types: 4301------------------------------ 4302 4303U-Boot supports the following image types: 4304 4305 "Standalone Programs" are directly runnable in the environment 4306 provided by U-Boot; it is expected that (if they behave 4307 well) you can continue to work in U-Boot after return from 4308 the Standalone Program. 4309 "OS Kernel Images" are usually images of some Embedded OS which 4310 will take over control completely. Usually these programs 4311 will install their own set of exception handlers, device 4312 drivers, set up the MMU, etc. - this means, that you cannot 4313 expect to re-enter U-Boot except by resetting the CPU. 4314 "RAMDisk Images" are more or less just data blocks, and their 4315 parameters (address, size) are passed to an OS kernel that is 4316 being started. 4317 "Multi-File Images" contain several images, typically an OS 4318 (Linux) kernel image and one or more data images like 4319 RAMDisks. This construct is useful for instance when you want 4320 to boot over the network using BOOTP etc., where the boot 4321 server provides just a single image file, but you want to get 4322 for instance an OS kernel and a RAMDisk image. 4323 4324 "Multi-File Images" start with a list of image sizes, each 4325 image size (in bytes) specified by an "uint32_t" in network 4326 byte order. This list is terminated by an "(uint32_t)0". 4327 Immediately after the terminating 0 follow the images, one by 4328 one, all aligned on "uint32_t" boundaries (size rounded up to 4329 a multiple of 4 bytes). 4330 4331 "Firmware Images" are binary images containing firmware (like 4332 U-Boot or FPGA images) which usually will be programmed to 4333 flash memory. 4334 4335 "Script files" are command sequences that will be executed by 4336 U-Boot's command interpreter; this feature is especially 4337 useful when you configure U-Boot to use a real shell (hush) 4338 as command interpreter. 4339 4340 4341Standalone HOWTO: 4342================= 4343 4344One of the features of U-Boot is that you can dynamically load and 4345run "standalone" applications, which can use some resources of 4346U-Boot like console I/O functions or interrupt services. 4347 4348Two simple examples are included with the sources: 4349 4350"Hello World" Demo: 4351------------------- 4352 4353'examples/hello_world.c' contains a small "Hello World" Demo 4354application; it is automatically compiled when you build U-Boot. 4355It's configured to run at address 0x00040004, so you can play with it 4356like that: 4357 4358 => loads 4359 ## Ready for S-Record download ... 4360 ~>examples/hello_world.srec 4361 1 2 3 4 5 6 7 8 9 10 11 ... 4362 [file transfer complete] 4363 [connected] 4364 ## Start Addr = 0x00040004 4365 4366 => go 40004 Hello World! This is a test. 4367 ## Starting application at 0x00040004 ... 4368 Hello World 4369 argc = 7 4370 argv[0] = "40004" 4371 argv[1] = "Hello" 4372 argv[2] = "World!" 4373 argv[3] = "This" 4374 argv[4] = "is" 4375 argv[5] = "a" 4376 argv[6] = "test." 4377 argv[7] = "<NULL>" 4378 Hit any key to exit ... 4379 4380 ## Application terminated, rc = 0x0 4381 4382Another example, which demonstrates how to register a CPM interrupt 4383handler with the U-Boot code, can be found in 'examples/timer.c'. 4384Here, a CPM timer is set up to generate an interrupt every second. 4385The interrupt service routine is trivial, just printing a '.' 4386character, but this is just a demo program. The application can be 4387controlled by the following keys: 4388 4389 ? - print current values og the CPM Timer registers 4390 b - enable interrupts and start timer 4391 e - stop timer and disable interrupts 4392 q - quit application 4393 4394 => loads 4395 ## Ready for S-Record download ... 4396 ~>examples/timer.srec 4397 1 2 3 4 5 6 7 8 9 10 11 ... 4398 [file transfer complete] 4399 [connected] 4400 ## Start Addr = 0x00040004 4401 4402 => go 40004 4403 ## Starting application at 0x00040004 ... 4404 TIMERS=0xfff00980 4405 Using timer 1 4406 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 4407 4408Hit 'b': 4409 [q, b, e, ?] Set interval 1000000 us 4410 Enabling timer 4411Hit '?': 4412 [q, b, e, ?] ........ 4413 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 4414Hit '?': 4415 [q, b, e, ?] . 4416 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 4417Hit '?': 4418 [q, b, e, ?] . 4419 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 4420Hit '?': 4421 [q, b, e, ?] . 4422 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 4423Hit 'e': 4424 [q, b, e, ?] ...Stopping timer 4425Hit 'q': 4426 [q, b, e, ?] ## Application terminated, rc = 0x0 4427 4428 4429Minicom warning: 4430================ 4431 4432Over time, many people have reported problems when trying to use the 4433"minicom" terminal emulation program for serial download. I (wd) 4434consider minicom to be broken, and recommend not to use it. Under 4435Unix, I recommend to use C-Kermit for general purpose use (and 4436especially for kermit binary protocol download ("loadb" command), and 4437use "cu" for S-Record download ("loads" command). 4438 4439Nevertheless, if you absolutely want to use it try adding this 4440configuration to your "File transfer protocols" section: 4441 4442 Name Program Name U/D FullScr IO-Red. Multi 4443 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N 4444 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N 4445 4446 4447NetBSD Notes: 4448============= 4449 4450Starting at version 0.9.2, U-Boot supports NetBSD both as host 4451(build U-Boot) and target system (boots NetBSD/mpc8xx). 4452 4453Building requires a cross environment; it is known to work on 4454NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 4455need gmake since the Makefiles are not compatible with BSD make). 4456Note that the cross-powerpc package does not install include files; 4457attempting to build U-Boot will fail because <machine/ansi.h> is 4458missing. This file has to be installed and patched manually: 4459 4460 # cd /usr/pkg/cross/powerpc-netbsd/include 4461 # mkdir powerpc 4462 # ln -s powerpc machine 4463 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 4464 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 4465 4466Native builds *don't* work due to incompatibilities between native 4467and U-Boot include files. 4468 4469Booting assumes that (the first part of) the image booted is a 4470stage-2 loader which in turn loads and then invokes the kernel 4471proper. Loader sources will eventually appear in the NetBSD source 4472tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 4473meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz 4474 4475 4476Implementation Internals: 4477========================= 4478 4479The following is not intended to be a complete description of every 4480implementation detail. However, it should help to understand the 4481inner workings of U-Boot and make it easier to port it to custom 4482hardware. 4483 4484 4485Initial Stack, Global Data: 4486--------------------------- 4487 4488The implementation of U-Boot is complicated by the fact that U-Boot 4489starts running out of ROM (flash memory), usually without access to 4490system RAM (because the memory controller is not initialized yet). 4491This means that we don't have writable Data or BSS segments, and BSS 4492is not initialized as zero. To be able to get a C environment working 4493at all, we have to allocate at least a minimal stack. Implementation 4494options for this are defined and restricted by the CPU used: Some CPU 4495models provide on-chip memory (like the IMMR area on MPC8xx and 4496MPC826x processors), on others (parts of) the data cache can be 4497locked as (mis-) used as memory, etc. 4498 4499 Chris Hallinan posted a good summary of these issues to the 4500 U-Boot mailing list: 4501 4502 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 4503 From: "Chris Hallinan" <clh@net1plus.com> 4504 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 4505 ... 4506 4507 Correct me if I'm wrong, folks, but the way I understand it 4508 is this: Using DCACHE as initial RAM for Stack, etc, does not 4509 require any physical RAM backing up the cache. The cleverness 4510 is that the cache is being used as a temporary supply of 4511 necessary storage before the SDRAM controller is setup. It's 4512 beyond the scope of this list to explain the details, but you 4513 can see how this works by studying the cache architecture and 4514 operation in the architecture and processor-specific manuals. 4515 4516 OCM is On Chip Memory, which I believe the 405GP has 4K. It 4517 is another option for the system designer to use as an 4518 initial stack/RAM area prior to SDRAM being available. Either 4519 option should work for you. Using CS 4 should be fine if your 4520 board designers haven't used it for something that would 4521 cause you grief during the initial boot! It is frequently not 4522 used. 4523 4524 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere 4525 with your processor/board/system design. The default value 4526 you will find in any recent u-boot distribution in 4527 walnut.h should work for you. I'd set it to a value larger 4528 than your SDRAM module. If you have a 64MB SDRAM module, set 4529 it above 400_0000. Just make sure your board has no resources 4530 that are supposed to respond to that address! That code in 4531 start.S has been around a while and should work as is when 4532 you get the config right. 4533 4534 -Chris Hallinan 4535 DS4.COM, Inc. 4536 4537It is essential to remember this, since it has some impact on the C 4538code for the initialization procedures: 4539 4540* Initialized global data (data segment) is read-only. Do not attempt 4541 to write it. 4542 4543* Do not use any uninitialized global data (or implicitely initialized 4544 as zero data - BSS segment) at all - this is undefined, initiali- 4545 zation is performed later (when relocating to RAM). 4546 4547* Stack space is very limited. Avoid big data buffers or things like 4548 that. 4549 4550Having only the stack as writable memory limits means we cannot use 4551normal global data to share information beween the code. But it 4552turned out that the implementation of U-Boot can be greatly 4553simplified by making a global data structure (gd_t) available to all 4554functions. We could pass a pointer to this data as argument to _all_ 4555functions, but this would bloat the code. Instead we use a feature of 4556the GCC compiler (Global Register Variables) to share the data: we 4557place a pointer (gd) to the global data into a register which we 4558reserve for this purpose. 4559 4560When choosing a register for such a purpose we are restricted by the 4561relevant (E)ABI specifications for the current architecture, and by 4562GCC's implementation. 4563 4564For PowerPC, the following registers have specific use: 4565 R1: stack pointer 4566 R2: reserved for system use 4567 R3-R4: parameter passing and return values 4568 R5-R10: parameter passing 4569 R13: small data area pointer 4570 R30: GOT pointer 4571 R31: frame pointer 4572 4573 (U-Boot also uses R12 as internal GOT pointer. r12 4574 is a volatile register so r12 needs to be reset when 4575 going back and forth between asm and C) 4576 4577 ==> U-Boot will use R2 to hold a pointer to the global data 4578 4579 Note: on PPC, we could use a static initializer (since the 4580 address of the global data structure is known at compile time), 4581 but it turned out that reserving a register results in somewhat 4582 smaller code - although the code savings are not that big (on 4583 average for all boards 752 bytes for the whole U-Boot image, 4584 624 text + 127 data). 4585 4586On Blackfin, the normal C ABI (except for P3) is followed as documented here: 4587 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface 4588 4589 ==> U-Boot will use P3 to hold a pointer to the global data 4590 4591On ARM, the following registers are used: 4592 4593 R0: function argument word/integer result 4594 R1-R3: function argument word 4595 R9: GOT pointer 4596 R10: stack limit (used only if stack checking if enabled) 4597 R11: argument (frame) pointer 4598 R12: temporary workspace 4599 R13: stack pointer 4600 R14: link register 4601 R15: program counter 4602 4603 ==> U-Boot will use R8 to hold a pointer to the global data 4604 4605On Nios II, the ABI is documented here: 4606 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf 4607 4608 ==> U-Boot will use gp to hold a pointer to the global data 4609 4610 Note: on Nios II, we give "-G0" option to gcc and don't use gp 4611 to access small data sections, so gp is free. 4612 4613On NDS32, the following registers are used: 4614 4615 R0-R1: argument/return 4616 R2-R5: argument 4617 R15: temporary register for assembler 4618 R16: trampoline register 4619 R28: frame pointer (FP) 4620 R29: global pointer (GP) 4621 R30: link register (LP) 4622 R31: stack pointer (SP) 4623 PC: program counter (PC) 4624 4625 ==> U-Boot will use R10 to hold a pointer to the global data 4626 4627NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope, 4628or current versions of GCC may "optimize" the code too much. 4629 4630Memory Management: 4631------------------ 4632 4633U-Boot runs in system state and uses physical addresses, i.e. the 4634MMU is not used either for address mapping nor for memory protection. 4635 4636The available memory is mapped to fixed addresses using the memory 4637controller. In this process, a contiguous block is formed for each 4638memory type (Flash, SDRAM, SRAM), even when it consists of several 4639physical memory banks. 4640 4641U-Boot is installed in the first 128 kB of the first Flash bank (on 4642TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 4643booting and sizing and initializing DRAM, the code relocates itself 4644to the upper end of DRAM. Immediately below the U-Boot code some 4645memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN 4646configuration setting]. Below that, a structure with global Board 4647Info data is placed, followed by the stack (growing downward). 4648 4649Additionally, some exception handler code is copied to the low 8 kB 4650of DRAM (0x00000000 ... 0x00001FFF). 4651 4652So a typical memory configuration with 16 MB of DRAM could look like 4653this: 4654 4655 0x0000 0000 Exception Vector code 4656 : 4657 0x0000 1FFF 4658 0x0000 2000 Free for Application Use 4659 : 4660 : 4661 4662 : 4663 : 4664 0x00FB FF20 Monitor Stack (Growing downward) 4665 0x00FB FFAC Board Info Data and permanent copy of global data 4666 0x00FC 0000 Malloc Arena 4667 : 4668 0x00FD FFFF 4669 0x00FE 0000 RAM Copy of Monitor Code 4670 ... eventually: LCD or video framebuffer 4671 ... eventually: pRAM (Protected RAM - unchanged by reset) 4672 0x00FF FFFF [End of RAM] 4673 4674 4675System Initialization: 4676---------------------- 4677 4678In the reset configuration, U-Boot starts at the reset entry point 4679(on most PowerPC systems at address 0x00000100). Because of the reset 4680configuration for CS0# this is a mirror of the onboard Flash memory. 4681To be able to re-map memory U-Boot then jumps to its link address. 4682To be able to implement the initialization code in C, a (small!) 4683initial stack is set up in the internal Dual Ported RAM (in case CPUs 4684which provide such a feature like MPC8xx or MPC8260), or in a locked 4685part of the data cache. After that, U-Boot initializes the CPU core, 4686the caches and the SIU. 4687 4688Next, all (potentially) available memory banks are mapped using a 4689preliminary mapping. For example, we put them on 512 MB boundaries 4690(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 4691on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 4692programmed for SDRAM access. Using the temporary configuration, a 4693simple memory test is run that determines the size of the SDRAM 4694banks. 4695 4696When there is more than one SDRAM bank, and the banks are of 4697different size, the largest is mapped first. For equal size, the first 4698bank (CS2#) is mapped first. The first mapping is always for address 46990x00000000, with any additional banks following immediately to create 4700contiguous memory starting from 0. 4701 4702Then, the monitor installs itself at the upper end of the SDRAM area 4703and allocates memory for use by malloc() and for the global Board 4704Info data; also, the exception vector code is copied to the low RAM 4705pages, and the final stack is set up. 4706 4707Only after this relocation will you have a "normal" C environment; 4708until that you are restricted in several ways, mostly because you are 4709running from ROM, and because the code will have to be relocated to a 4710new address in RAM. 4711 4712 4713U-Boot Porting Guide: 4714---------------------- 4715 4716[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 4717list, October 2002] 4718 4719 4720int main(int argc, char *argv[]) 4721{ 4722 sighandler_t no_more_time; 4723 4724 signal(SIGALRM, no_more_time); 4725 alarm(PROJECT_DEADLINE - toSec (3 * WEEK)); 4726 4727 if (available_money > available_manpower) { 4728 Pay consultant to port U-Boot; 4729 return 0; 4730 } 4731 4732 Download latest U-Boot source; 4733 4734 Subscribe to u-boot mailing list; 4735 4736 if (clueless) 4737 email("Hi, I am new to U-Boot, how do I get started?"); 4738 4739 while (learning) { 4740 Read the README file in the top level directory; 4741 Read http://www.denx.de/twiki/bin/view/DULG/Manual; 4742 Read applicable doc/*.README; 4743 Read the source, Luke; 4744 /* find . -name "*.[chS]" | xargs grep -i <keyword> */ 4745 } 4746 4747 if (available_money > toLocalCurrency ($2500)) 4748 Buy a BDI3000; 4749 else 4750 Add a lot of aggravation and time; 4751 4752 if (a similar board exists) { /* hopefully... */ 4753 cp -a board/<similar> board/<myboard> 4754 cp include/configs/<similar>.h include/configs/<myboard>.h 4755 } else { 4756 Create your own board support subdirectory; 4757 Create your own board include/configs/<myboard>.h file; 4758 } 4759 Edit new board/<myboard> files 4760 Edit new include/configs/<myboard>.h 4761 4762 while (!accepted) { 4763 while (!running) { 4764 do { 4765 Add / modify source code; 4766 } until (compiles); 4767 Debug; 4768 if (clueless) 4769 email("Hi, I am having problems..."); 4770 } 4771 Send patch file to the U-Boot email list; 4772 if (reasonable critiques) 4773 Incorporate improvements from email list code review; 4774 else 4775 Defend code as written; 4776 } 4777 4778 return 0; 4779} 4780 4781void no_more_time (int sig) 4782{ 4783 hire_a_guru(); 4784} 4785 4786 4787Coding Standards: 4788----------------- 4789 4790All contributions to U-Boot should conform to the Linux kernel 4791coding style; see the file "Documentation/CodingStyle" and the script 4792"scripts/Lindent" in your Linux kernel source directory. 4793 4794Source files originating from a different project (for example the 4795MTD subsystem) are generally exempt from these guidelines and are not 4796reformated to ease subsequent migration to newer versions of those 4797sources. 4798 4799Please note that U-Boot is implemented in C (and to some small parts in 4800Assembler); no C++ is used, so please do not use C++ style comments (//) 4801in your code. 4802 4803Please also stick to the following formatting rules: 4804- remove any trailing white space 4805- use TAB characters for indentation and vertical alignment, not spaces 4806- make sure NOT to use DOS '\r\n' line feeds 4807- do not add more than 2 consecutive empty lines to source files 4808- do not add trailing empty lines to source files 4809 4810Submissions which do not conform to the standards may be returned 4811with a request to reformat the changes. 4812 4813 4814Submitting Patches: 4815------------------- 4816 4817Since the number of patches for U-Boot is growing, we need to 4818establish some rules. Submissions which do not conform to these rules 4819may be rejected, even when they contain important and valuable stuff. 4820 4821Please see http://www.denx.de/wiki/U-Boot/Patches for details. 4822 4823Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>; 4824see http://lists.denx.de/mailman/listinfo/u-boot 4825 4826When you send a patch, please include the following information with 4827it: 4828 4829* For bug fixes: a description of the bug and how your patch fixes 4830 this bug. Please try to include a way of demonstrating that the 4831 patch actually fixes something. 4832 4833* For new features: a description of the feature and your 4834 implementation. 4835 4836* A CHANGELOG entry as plaintext (separate from the patch) 4837 4838* For major contributions, your entry to the CREDITS file 4839 4840* When you add support for a new board, don't forget to add this 4841 board to the MAINTAINERS file, too. 4842 4843* If your patch adds new configuration options, don't forget to 4844 document these in the README file. 4845 4846* The patch itself. If you are using git (which is *strongly* 4847 recommended) you can easily generate the patch using the 4848 "git format-patch". If you then use "git send-email" to send it to 4849 the U-Boot mailing list, you will avoid most of the common problems 4850 with some other mail clients. 4851 4852 If you cannot use git, use "diff -purN OLD NEW". If your version of 4853 diff does not support these options, then get the latest version of 4854 GNU diff. 4855 4856 The current directory when running this command shall be the parent 4857 directory of the U-Boot source tree (i. e. please make sure that 4858 your patch includes sufficient directory information for the 4859 affected files). 4860 4861 We prefer patches as plain text. MIME attachments are discouraged, 4862 and compressed attachments must not be used. 4863 4864* If one logical set of modifications affects or creates several 4865 files, all these changes shall be submitted in a SINGLE patch file. 4866 4867* Changesets that contain different, unrelated modifications shall be 4868 submitted as SEPARATE patches, one patch per changeset. 4869 4870 4871Notes: 4872 4873* Before sending the patch, run the MAKEALL script on your patched 4874 source tree and make sure that no errors or warnings are reported 4875 for any of the boards. 4876 4877* Keep your modifications to the necessary minimum: A patch 4878 containing several unrelated changes or arbitrary reformats will be 4879 returned with a request to re-formatting / split it. 4880 4881* If you modify existing code, make sure that your new code does not 4882 add to the memory footprint of the code ;-) Small is beautiful! 4883 When adding new features, these should compile conditionally only 4884 (using #ifdef), and the resulting code with the new feature 4885 disabled must not need more memory than the old code without your 4886 modification. 4887 4888* Remember that there is a size limit of 100 kB per message on the 4889 u-boot mailing list. Bigger patches will be moderated. If they are 4890 reasonable and not too big, they will be acknowledged. But patches 4891 bigger than the size limit should be avoided. 4892