1# 2# (C) Copyright 2000 - 2013 3# Wolfgang Denk, DENX Software Engineering, wd@denx.de. 4# 5# SPDX-License-Identifier: GPL-2.0+ 6# 7 8Summary: 9======== 10 11This directory contains the source code for U-Boot, a boot loader for 12Embedded boards based on PowerPC, ARM, MIPS and several other 13processors, which can be installed in a boot ROM and used to 14initialize and test the hardware or to download and run application 15code. 16 17The development of U-Boot is closely related to Linux: some parts of 18the source code originate in the Linux source tree, we have some 19header files in common, and special provision has been made to 20support booting of Linux images. 21 22Some attention has been paid to make this software easily 23configurable and extendable. For instance, all monitor commands are 24implemented with the same call interface, so that it's very easy to 25add new commands. Also, instead of permanently adding rarely used 26code (for instance hardware test utilities) to the monitor, you can 27load and run it dynamically. 28 29 30Status: 31======= 32 33In general, all boards for which a configuration option exists in the 34Makefile have been tested to some extent and can be considered 35"working". In fact, many of them are used in production systems. 36 37In case of problems see the CHANGELOG and CREDITS files to find out 38who contributed the specific port. The boards.cfg file lists board 39maintainers. 40 41Note: There is no CHANGELOG file in the actual U-Boot source tree; 42it can be created dynamically from the Git log using: 43 44 make CHANGELOG 45 46 47Where to get help: 48================== 49 50In case you have questions about, problems with or contributions for 51U-Boot you should send a message to the U-Boot mailing list at 52<u-boot@lists.denx.de>. There is also an archive of previous traffic 53on the mailing list - please search the archive before asking FAQ's. 54Please see http://lists.denx.de/pipermail/u-boot and 55http://dir.gmane.org/gmane.comp.boot-loaders.u-boot 56 57 58Where to get source code: 59========================= 60 61The U-Boot source code is maintained in the git repository at 62git://www.denx.de/git/u-boot.git ; you can browse it online at 63http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary 64 65The "snapshot" links on this page allow you to download tarballs of 66any version you might be interested in. Official releases are also 67available for FTP download from the ftp://ftp.denx.de/pub/u-boot/ 68directory. 69 70Pre-built (and tested) images are available from 71ftp://ftp.denx.de/pub/u-boot/images/ 72 73 74Where we come from: 75=================== 76 77- start from 8xxrom sources 78- create PPCBoot project (http://sourceforge.net/projects/ppcboot) 79- clean up code 80- make it easier to add custom boards 81- make it possible to add other [PowerPC] CPUs 82- extend functions, especially: 83 * Provide extended interface to Linux boot loader 84 * S-Record download 85 * network boot 86 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot 87- create ARMBoot project (http://sourceforge.net/projects/armboot) 88- add other CPU families (starting with ARM) 89- create U-Boot project (http://sourceforge.net/projects/u-boot) 90- current project page: see http://www.denx.de/wiki/U-Boot 91 92 93Names and Spelling: 94=================== 95 96The "official" name of this project is "Das U-Boot". The spelling 97"U-Boot" shall be used in all written text (documentation, comments 98in source files etc.). Example: 99 100 This is the README file for the U-Boot project. 101 102File names etc. shall be based on the string "u-boot". Examples: 103 104 include/asm-ppc/u-boot.h 105 106 #include <asm/u-boot.h> 107 108Variable names, preprocessor constants etc. shall be either based on 109the string "u_boot" or on "U_BOOT". Example: 110 111 U_BOOT_VERSION u_boot_logo 112 IH_OS_U_BOOT u_boot_hush_start 113 114 115Versioning: 116=========== 117 118Starting with the release in October 2008, the names of the releases 119were changed from numerical release numbers without deeper meaning 120into a time stamp based numbering. Regular releases are identified by 121names consisting of the calendar year and month of the release date. 122Additional fields (if present) indicate release candidates or bug fix 123releases in "stable" maintenance trees. 124 125Examples: 126 U-Boot v2009.11 - Release November 2009 127 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree 128 U-Boot v2010.09-rc1 - Release candiate 1 for September 2010 release 129 130 131Directory Hierarchy: 132==================== 133 134/arch Architecture specific files 135 /arm Files generic to ARM architecture 136 /cpu CPU specific files 137 /arm720t Files specific to ARM 720 CPUs 138 /arm920t Files specific to ARM 920 CPUs 139 /at91 Files specific to Atmel AT91RM9200 CPU 140 /imx Files specific to Freescale MC9328 i.MX CPUs 141 /s3c24x0 Files specific to Samsung S3C24X0 CPUs 142 /arm926ejs Files specific to ARM 926 CPUs 143 /arm1136 Files specific to ARM 1136 CPUs 144 /ixp Files specific to Intel XScale IXP CPUs 145 /pxa Files specific to Intel XScale PXA CPUs 146 /sa1100 Files specific to Intel StrongARM SA1100 CPUs 147 /lib Architecture specific library files 148 /avr32 Files generic to AVR32 architecture 149 /cpu CPU specific files 150 /lib Architecture specific library files 151 /blackfin Files generic to Analog Devices Blackfin architecture 152 /cpu CPU specific files 153 /lib Architecture specific library files 154 /x86 Files generic to x86 architecture 155 /cpu CPU specific files 156 /lib Architecture specific library files 157 /m68k Files generic to m68k architecture 158 /cpu CPU specific files 159 /mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs 160 /mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs 161 /mcf532x Files specific to Freescale ColdFire MCF5329 CPUs 162 /mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs 163 /mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs 164 /lib Architecture specific library files 165 /microblaze Files generic to microblaze architecture 166 /cpu CPU specific files 167 /lib Architecture specific library files 168 /mips Files generic to MIPS architecture 169 /cpu CPU specific files 170 /mips32 Files specific to MIPS32 CPUs 171 /xburst Files specific to Ingenic XBurst CPUs 172 /lib Architecture specific library files 173 /nds32 Files generic to NDS32 architecture 174 /cpu CPU specific files 175 /n1213 Files specific to Andes Technology N1213 CPUs 176 /lib Architecture specific library files 177 /nios2 Files generic to Altera NIOS2 architecture 178 /cpu CPU specific files 179 /lib Architecture specific library files 180 /powerpc Files generic to PowerPC architecture 181 /cpu CPU specific files 182 /74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs 183 /mpc5xx Files specific to Freescale MPC5xx CPUs 184 /mpc5xxx Files specific to Freescale MPC5xxx CPUs 185 /mpc8xx Files specific to Freescale MPC8xx CPUs 186 /mpc824x Files specific to Freescale MPC824x CPUs 187 /mpc8260 Files specific to Freescale MPC8260 CPUs 188 /mpc85xx Files specific to Freescale MPC85xx CPUs 189 /ppc4xx Files specific to AMCC PowerPC 4xx CPUs 190 /lib Architecture specific library files 191 /sh Files generic to SH architecture 192 /cpu CPU specific files 193 /sh2 Files specific to sh2 CPUs 194 /sh3 Files specific to sh3 CPUs 195 /sh4 Files specific to sh4 CPUs 196 /lib Architecture specific library files 197 /sparc Files generic to SPARC architecture 198 /cpu CPU specific files 199 /leon2 Files specific to Gaisler LEON2 SPARC CPU 200 /leon3 Files specific to Gaisler LEON3 SPARC CPU 201 /lib Architecture specific library files 202/api Machine/arch independent API for external apps 203/board Board dependent files 204/common Misc architecture independent functions 205/disk Code for disk drive partition handling 206/doc Documentation (don't expect too much) 207/drivers Commonly used device drivers 208/examples Example code for standalone applications, etc. 209/fs Filesystem code (cramfs, ext2, jffs2, etc.) 210/include Header Files 211/lib Files generic to all architectures 212 /libfdt Library files to support flattened device trees 213 /lzma Library files to support LZMA decompression 214 /lzo Library files to support LZO decompression 215/net Networking code 216/post Power On Self Test 217/rtc Real Time Clock drivers 218/tools Tools to build S-Record or U-Boot images, etc. 219 220Software Configuration: 221======================= 222 223Configuration is usually done using C preprocessor defines; the 224rationale behind that is to avoid dead code whenever possible. 225 226There are two classes of configuration variables: 227 228* Configuration _OPTIONS_: 229 These are selectable by the user and have names beginning with 230 "CONFIG_". 231 232* Configuration _SETTINGS_: 233 These depend on the hardware etc. and should not be meddled with if 234 you don't know what you're doing; they have names beginning with 235 "CONFIG_SYS_". 236 237Later we will add a configuration tool - probably similar to or even 238identical to what's used for the Linux kernel. Right now, we have to 239do the configuration by hand, which means creating some symbolic 240links and editing some configuration files. We use the TQM8xxL boards 241as an example here. 242 243 244Selection of Processor Architecture and Board Type: 245--------------------------------------------------- 246 247For all supported boards there are ready-to-use default 248configurations available; just type "make <board_name>_config". 249 250Example: For a TQM823L module type: 251 252 cd u-boot 253 make TQM823L_config 254 255For the Cogent platform, you need to specify the CPU type as well; 256e.g. "make cogent_mpc8xx_config". And also configure the cogent 257directory according to the instructions in cogent/README. 258 259 260Configuration Options: 261---------------------- 262 263Configuration depends on the combination of board and CPU type; all 264such information is kept in a configuration file 265"include/configs/<board_name>.h". 266 267Example: For a TQM823L module, all configuration settings are in 268"include/configs/TQM823L.h". 269 270 271Many of the options are named exactly as the corresponding Linux 272kernel configuration options. The intention is to make it easier to 273build a config tool - later. 274 275 276The following options need to be configured: 277 278- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX. 279 280- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS. 281 282- CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined) 283 Define exactly one, e.g. CONFIG_ATSTK1002 284 285- CPU Module Type: (if CONFIG_COGENT is defined) 286 Define exactly one of 287 CONFIG_CMA286_60_OLD 288--- FIXME --- not tested yet: 289 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P, 290 CONFIG_CMA287_23, CONFIG_CMA287_50 291 292- Motherboard Type: (if CONFIG_COGENT is defined) 293 Define exactly one of 294 CONFIG_CMA101, CONFIG_CMA102 295 296- Motherboard I/O Modules: (if CONFIG_COGENT is defined) 297 Define one or more of 298 CONFIG_CMA302 299 300- Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined) 301 Define one or more of 302 CONFIG_LCD_HEARTBEAT - update a character position on 303 the LCD display every second with 304 a "rotator" |\-/|\-/ 305 306- Board flavour: (if CONFIG_MPC8260ADS is defined) 307 CONFIG_ADSTYPE 308 Possible values are: 309 CONFIG_SYS_8260ADS - original MPC8260ADS 310 CONFIG_SYS_8266ADS - MPC8266ADS 311 CONFIG_SYS_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR 312 CONFIG_SYS_8272ADS - MPC8272ADS 313 314- Marvell Family Member 315 CONFIG_SYS_MVFS - define it if you want to enable 316 multiple fs option at one time 317 for marvell soc family 318 319- MPC824X Family Member (if CONFIG_MPC824X is defined) 320 Define exactly one of 321 CONFIG_MPC8240, CONFIG_MPC8245 322 323- 8xx CPU Options: (if using an MPC8xx CPU) 324 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if 325 get_gclk_freq() cannot work 326 e.g. if there is no 32KHz 327 reference PIT/RTC clock 328 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK 329 or XTAL/EXTAL) 330 331- 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU): 332 CONFIG_SYS_8xx_CPUCLK_MIN 333 CONFIG_SYS_8xx_CPUCLK_MAX 334 CONFIG_8xx_CPUCLK_DEFAULT 335 See doc/README.MPC866 336 337 CONFIG_SYS_MEASURE_CPUCLK 338 339 Define this to measure the actual CPU clock instead 340 of relying on the correctness of the configured 341 values. Mostly useful for board bringup to make sure 342 the PLL is locked at the intended frequency. Note 343 that this requires a (stable) reference clock (32 kHz 344 RTC clock or CONFIG_SYS_8XX_XIN) 345 346 CONFIG_SYS_DELAYED_ICACHE 347 348 Define this option if you want to enable the 349 ICache only when Code runs from RAM. 350 351- 85xx CPU Options: 352 CONFIG_SYS_PPC64 353 354 Specifies that the core is a 64-bit PowerPC implementation (implements 355 the "64" category of the Power ISA). This is necessary for ePAPR 356 compliance, among other possible reasons. 357 358 CONFIG_SYS_FSL_TBCLK_DIV 359 360 Defines the core time base clock divider ratio compared to the 361 system clock. On most PQ3 devices this is 8, on newer QorIQ 362 devices it can be 16 or 32. The ratio varies from SoC to Soc. 363 364 CONFIG_SYS_FSL_PCIE_COMPAT 365 366 Defines the string to utilize when trying to match PCIe device 367 tree nodes for the given platform. 368 369 CONFIG_SYS_PPC_E500_DEBUG_TLB 370 371 Enables a temporary TLB entry to be used during boot to work 372 around limitations in e500v1 and e500v2 external debugger 373 support. This reduces the portions of the boot code where 374 breakpoints and single stepping do not work. The value of this 375 symbol should be set to the TLB1 entry to be used for this 376 purpose. 377 378 CONFIG_SYS_FSL_ERRATUM_A004510 379 380 Enables a workaround for erratum A004510. If set, 381 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and 382 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set. 383 384 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV 385 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional) 386 387 Defines one or two SoC revisions (low 8 bits of SVR) 388 for which the A004510 workaround should be applied. 389 390 The rest of SVR is either not relevant to the decision 391 of whether the erratum is present (e.g. p2040 versus 392 p2041) or is implied by the build target, which controls 393 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set. 394 395 See Freescale App Note 4493 for more information about 396 this erratum. 397 398 CONFIG_A003399_NOR_WORKAROUND 399 Enables a workaround for IFC erratum A003399. It is only 400 requred during NOR boot. 401 402 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY 403 404 This is the value to write into CCSR offset 0x18600 405 according to the A004510 workaround. 406 407 CONFIG_SYS_FSL_DSP_DDR_ADDR 408 This value denotes start offset of DDR memory which is 409 connected exclusively to the DSP cores. 410 411 CONFIG_SYS_FSL_DSP_M2_RAM_ADDR 412 This value denotes start offset of M2 memory 413 which is directly connected to the DSP core. 414 415 CONFIG_SYS_FSL_DSP_M3_RAM_ADDR 416 This value denotes start offset of M3 memory which is directly 417 connected to the DSP core. 418 419 CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT 420 This value denotes start offset of DSP CCSR space. 421 422 CONFIG_SYS_FSL_DDR_EMU 423 Specify emulator support for DDR. Some DDR features such as 424 deskew training are not available. 425 426- Generic CPU options: 427 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN 428 429 Defines the endianess of the CPU. Implementation of those 430 values is arch specific. 431 432- Intel Monahans options: 433 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO 434 435 Defines the Monahans run mode to oscillator 436 ratio. Valid values are 8, 16, 24, 31. The core 437 frequency is this value multiplied by 13 MHz. 438 439 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO 440 441 Defines the Monahans turbo mode to oscillator 442 ratio. Valid values are 1 (default if undefined) and 443 2. The core frequency as calculated above is multiplied 444 by this value. 445 446- MIPS CPU options: 447 CONFIG_SYS_INIT_SP_OFFSET 448 449 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack 450 pointer. This is needed for the temporary stack before 451 relocation. 452 453 CONFIG_SYS_MIPS_CACHE_MODE 454 455 Cache operation mode for the MIPS CPU. 456 See also arch/mips/include/asm/mipsregs.h. 457 Possible values are: 458 CONF_CM_CACHABLE_NO_WA 459 CONF_CM_CACHABLE_WA 460 CONF_CM_UNCACHED 461 CONF_CM_CACHABLE_NONCOHERENT 462 CONF_CM_CACHABLE_CE 463 CONF_CM_CACHABLE_COW 464 CONF_CM_CACHABLE_CUW 465 CONF_CM_CACHABLE_ACCELERATED 466 467 CONFIG_SYS_XWAY_EBU_BOOTCFG 468 469 Special option for Lantiq XWAY SoCs for booting from NOR flash. 470 See also arch/mips/cpu/mips32/start.S. 471 472 CONFIG_XWAY_SWAP_BYTES 473 474 Enable compilation of tools/xway-swap-bytes needed for Lantiq 475 XWAY SoCs for booting from NOR flash. The U-Boot image needs to 476 be swapped if a flash programmer is used. 477 478- ARM options: 479 CONFIG_SYS_EXCEPTION_VECTORS_HIGH 480 481 Select high exception vectors of the ARM core, e.g., do not 482 clear the V bit of the c1 register of CP15. 483 484 CONFIG_SYS_THUMB_BUILD 485 486 Use this flag to build U-Boot using the Thumb instruction 487 set for ARM architectures. Thumb instruction set provides 488 better code density. For ARM architectures that support 489 Thumb2 this flag will result in Thumb2 code generated by 490 GCC. 491 492 CONFIG_ARM_ERRATA_716044 493 CONFIG_ARM_ERRATA_742230 494 CONFIG_ARM_ERRATA_743622 495 CONFIG_ARM_ERRATA_751472 496 497 If set, the workarounds for these ARM errata are applied early 498 during U-Boot startup. Note that these options force the 499 workarounds to be applied; no CPU-type/version detection 500 exists, unlike the similar options in the Linux kernel. Do not 501 set these options unless they apply! 502 503- CPU timer options: 504 CONFIG_SYS_HZ 505 506 The frequency of the timer returned by get_timer(). 507 get_timer() must operate in milliseconds and this CONFIG 508 option must be set to 1000. 509 510- Linux Kernel Interface: 511 CONFIG_CLOCKS_IN_MHZ 512 513 U-Boot stores all clock information in Hz 514 internally. For binary compatibility with older Linux 515 kernels (which expect the clocks passed in the 516 bd_info data to be in MHz) the environment variable 517 "clocks_in_mhz" can be defined so that U-Boot 518 converts clock data to MHZ before passing it to the 519 Linux kernel. 520 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of 521 "clocks_in_mhz=1" is automatically included in the 522 default environment. 523 524 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only] 525 526 When transferring memsize parameter to linux, some versions 527 expect it to be in bytes, others in MB. 528 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes. 529 530 CONFIG_OF_LIBFDT 531 532 New kernel versions are expecting firmware settings to be 533 passed using flattened device trees (based on open firmware 534 concepts). 535 536 CONFIG_OF_LIBFDT 537 * New libfdt-based support 538 * Adds the "fdt" command 539 * The bootm command automatically updates the fdt 540 541 OF_CPU - The proper name of the cpus node (only required for 542 MPC512X and MPC5xxx based boards). 543 OF_SOC - The proper name of the soc node (only required for 544 MPC512X and MPC5xxx based boards). 545 OF_TBCLK - The timebase frequency. 546 OF_STDOUT_PATH - The path to the console device 547 548 boards with QUICC Engines require OF_QE to set UCC MAC 549 addresses 550 551 CONFIG_OF_BOARD_SETUP 552 553 Board code has addition modification that it wants to make 554 to the flat device tree before handing it off to the kernel 555 556 CONFIG_OF_BOOT_CPU 557 558 This define fills in the correct boot CPU in the boot 559 param header, the default value is zero if undefined. 560 561 CONFIG_OF_IDE_FIXUP 562 563 U-Boot can detect if an IDE device is present or not. 564 If not, and this new config option is activated, U-Boot 565 removes the ATA node from the DTS before booting Linux, 566 so the Linux IDE driver does not probe the device and 567 crash. This is needed for buggy hardware (uc101) where 568 no pull down resistor is connected to the signal IDE5V_DD7. 569 570 CONFIG_MACH_TYPE [relevant for ARM only][mandatory] 571 572 This setting is mandatory for all boards that have only one 573 machine type and must be used to specify the machine type 574 number as it appears in the ARM machine registry 575 (see http://www.arm.linux.org.uk/developer/machines/). 576 Only boards that have multiple machine types supported 577 in a single configuration file and the machine type is 578 runtime discoverable, do not have to use this setting. 579 580- vxWorks boot parameters: 581 582 bootvx constructs a valid bootline using the following 583 environments variables: bootfile, ipaddr, serverip, hostname. 584 It loads the vxWorks image pointed bootfile. 585 586 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name 587 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address 588 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server 589 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters 590 591 CONFIG_SYS_VXWORKS_ADD_PARAMS 592 593 Add it at the end of the bootline. E.g "u=username pw=secret" 594 595 Note: If a "bootargs" environment is defined, it will overwride 596 the defaults discussed just above. 597 598- Cache Configuration: 599 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot 600 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot 601 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot 602 603- Cache Configuration for ARM: 604 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache 605 controller 606 CONFIG_SYS_PL310_BASE - Physical base address of PL310 607 controller register space 608 609- Serial Ports: 610 CONFIG_PL010_SERIAL 611 612 Define this if you want support for Amba PrimeCell PL010 UARTs. 613 614 CONFIG_PL011_SERIAL 615 616 Define this if you want support for Amba PrimeCell PL011 UARTs. 617 618 CONFIG_PL011_CLOCK 619 620 If you have Amba PrimeCell PL011 UARTs, set this variable to 621 the clock speed of the UARTs. 622 623 CONFIG_PL01x_PORTS 624 625 If you have Amba PrimeCell PL010 or PL011 UARTs on your board, 626 define this to a list of base addresses for each (supported) 627 port. See e.g. include/configs/versatile.h 628 629 CONFIG_PL011_SERIAL_RLCR 630 631 Some vendor versions of PL011 serial ports (e.g. ST-Ericsson U8500) 632 have separate receive and transmit line control registers. Set 633 this variable to initialize the extra register. 634 635 CONFIG_PL011_SERIAL_FLUSH_ON_INIT 636 637 On some platforms (e.g. U8500) U-Boot is loaded by a second stage 638 boot loader that has already initialized the UART. Define this 639 variable to flush the UART at init time. 640 641 642- Console Interface: 643 Depending on board, define exactly one serial port 644 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2, 645 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial 646 console by defining CONFIG_8xx_CONS_NONE 647 648 Note: if CONFIG_8xx_CONS_NONE is defined, the serial 649 port routines must be defined elsewhere 650 (i.e. serial_init(), serial_getc(), ...) 651 652 CONFIG_CFB_CONSOLE 653 Enables console device for a color framebuffer. Needs following 654 defines (cf. smiLynxEM, i8042) 655 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation 656 (default big endian) 657 VIDEO_HW_RECTFILL graphic chip supports 658 rectangle fill 659 (cf. smiLynxEM) 660 VIDEO_HW_BITBLT graphic chip supports 661 bit-blit (cf. smiLynxEM) 662 VIDEO_VISIBLE_COLS visible pixel columns 663 (cols=pitch) 664 VIDEO_VISIBLE_ROWS visible pixel rows 665 VIDEO_PIXEL_SIZE bytes per pixel 666 VIDEO_DATA_FORMAT graphic data format 667 (0-5, cf. cfb_console.c) 668 VIDEO_FB_ADRS framebuffer address 669 VIDEO_KBD_INIT_FCT keyboard int fct 670 (i.e. i8042_kbd_init()) 671 VIDEO_TSTC_FCT test char fct 672 (i.e. i8042_tstc) 673 VIDEO_GETC_FCT get char fct 674 (i.e. i8042_getc) 675 CONFIG_CONSOLE_CURSOR cursor drawing on/off 676 (requires blink timer 677 cf. i8042.c) 678 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c) 679 CONFIG_CONSOLE_TIME display time/date info in 680 upper right corner 681 (requires CONFIG_CMD_DATE) 682 CONFIG_VIDEO_LOGO display Linux logo in 683 upper left corner 684 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of 685 linux_logo.h for logo. 686 Requires CONFIG_VIDEO_LOGO 687 CONFIG_CONSOLE_EXTRA_INFO 688 additional board info beside 689 the logo 690 691 When CONFIG_CFB_CONSOLE_ANSI is defined, console will support 692 a limited number of ANSI escape sequences (cursor control, 693 erase functions and limited graphics rendition control). 694 695 When CONFIG_CFB_CONSOLE is defined, video console is 696 default i/o. Serial console can be forced with 697 environment 'console=serial'. 698 699 When CONFIG_SILENT_CONSOLE is defined, all console 700 messages (by U-Boot and Linux!) can be silenced with 701 the "silent" environment variable. See 702 doc/README.silent for more information. 703 704- Console Baudrate: 705 CONFIG_BAUDRATE - in bps 706 Select one of the baudrates listed in 707 CONFIG_SYS_BAUDRATE_TABLE, see below. 708 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale 709 710- Console Rx buffer length 711 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define 712 the maximum receive buffer length for the SMC. 713 This option is actual only for 82xx and 8xx possible. 714 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE 715 must be defined, to setup the maximum idle timeout for 716 the SMC. 717 718- Pre-Console Buffer: 719 Prior to the console being initialised (i.e. serial UART 720 initialised etc) all console output is silently discarded. 721 Defining CONFIG_PRE_CONSOLE_BUFFER will cause U-Boot to 722 buffer any console messages prior to the console being 723 initialised to a buffer of size CONFIG_PRE_CON_BUF_SZ 724 bytes located at CONFIG_PRE_CON_BUF_ADDR. The buffer is 725 a circular buffer, so if more than CONFIG_PRE_CON_BUF_SZ 726 bytes are output before the console is initialised, the 727 earlier bytes are discarded. 728 729 'Sane' compilers will generate smaller code if 730 CONFIG_PRE_CON_BUF_SZ is a power of 2 731 732- Safe printf() functions 733 Define CONFIG_SYS_VSNPRINTF to compile in safe versions of 734 the printf() functions. These are defined in 735 include/vsprintf.h and include snprintf(), vsnprintf() and 736 so on. Code size increase is approximately 300-500 bytes. 737 If this option is not given then these functions will 738 silently discard their buffer size argument - this means 739 you are not getting any overflow checking in this case. 740 741- Boot Delay: CONFIG_BOOTDELAY - in seconds 742 Delay before automatically booting the default image; 743 set to -1 to disable autoboot. 744 set to -2 to autoboot with no delay and not check for abort 745 (even when CONFIG_ZERO_BOOTDELAY_CHECK is defined). 746 747 See doc/README.autoboot for these options that 748 work with CONFIG_BOOTDELAY. None are required. 749 CONFIG_BOOT_RETRY_TIME 750 CONFIG_BOOT_RETRY_MIN 751 CONFIG_AUTOBOOT_KEYED 752 CONFIG_AUTOBOOT_PROMPT 753 CONFIG_AUTOBOOT_DELAY_STR 754 CONFIG_AUTOBOOT_STOP_STR 755 CONFIG_AUTOBOOT_DELAY_STR2 756 CONFIG_AUTOBOOT_STOP_STR2 757 CONFIG_ZERO_BOOTDELAY_CHECK 758 CONFIG_RESET_TO_RETRY 759 760- Autoboot Command: 761 CONFIG_BOOTCOMMAND 762 Only needed when CONFIG_BOOTDELAY is enabled; 763 define a command string that is automatically executed 764 when no character is read on the console interface 765 within "Boot Delay" after reset. 766 767 CONFIG_BOOTARGS 768 This can be used to pass arguments to the bootm 769 command. The value of CONFIG_BOOTARGS goes into the 770 environment value "bootargs". 771 772 CONFIG_RAMBOOT and CONFIG_NFSBOOT 773 The value of these goes into the environment as 774 "ramboot" and "nfsboot" respectively, and can be used 775 as a convenience, when switching between booting from 776 RAM and NFS. 777 778- Pre-Boot Commands: 779 CONFIG_PREBOOT 780 781 When this option is #defined, the existence of the 782 environment variable "preboot" will be checked 783 immediately before starting the CONFIG_BOOTDELAY 784 countdown and/or running the auto-boot command resp. 785 entering interactive mode. 786 787 This feature is especially useful when "preboot" is 788 automatically generated or modified. For an example 789 see the LWMON board specific code: here "preboot" is 790 modified when the user holds down a certain 791 combination of keys on the (special) keyboard when 792 booting the systems 793 794- Serial Download Echo Mode: 795 CONFIG_LOADS_ECHO 796 If defined to 1, all characters received during a 797 serial download (using the "loads" command) are 798 echoed back. This might be needed by some terminal 799 emulations (like "cu"), but may as well just take 800 time on others. This setting #define's the initial 801 value of the "loads_echo" environment variable. 802 803- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined) 804 CONFIG_KGDB_BAUDRATE 805 Select one of the baudrates listed in 806 CONFIG_SYS_BAUDRATE_TABLE, see below. 807 808- Monitor Functions: 809 Monitor commands can be included or excluded 810 from the build by using the #include files 811 <config_cmd_all.h> and #undef'ing unwanted 812 commands, or using <config_cmd_default.h> 813 and augmenting with additional #define's 814 for wanted commands. 815 816 The default command configuration includes all commands 817 except those marked below with a "*". 818 819 CONFIG_CMD_ASKENV * ask for env variable 820 CONFIG_CMD_BDI bdinfo 821 CONFIG_CMD_BEDBUG * Include BedBug Debugger 822 CONFIG_CMD_BMP * BMP support 823 CONFIG_CMD_BSP * Board specific commands 824 CONFIG_CMD_BOOTD bootd 825 CONFIG_CMD_CACHE * icache, dcache 826 CONFIG_CMD_CONSOLE coninfo 827 CONFIG_CMD_CRC32 * crc32 828 CONFIG_CMD_DATE * support for RTC, date/time... 829 CONFIG_CMD_DHCP * DHCP support 830 CONFIG_CMD_DIAG * Diagnostics 831 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands 832 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command 833 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd 834 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command 835 CONFIG_CMD_DTT * Digital Therm and Thermostat 836 CONFIG_CMD_ECHO echo arguments 837 CONFIG_CMD_EDITENV edit env variable 838 CONFIG_CMD_EEPROM * EEPROM read/write support 839 CONFIG_CMD_ELF * bootelf, bootvx 840 CONFIG_CMD_ENV_CALLBACK * display details about env callbacks 841 CONFIG_CMD_ENV_FLAGS * display details about env flags 842 CONFIG_CMD_EXPORTENV * export the environment 843 CONFIG_CMD_EXT2 * ext2 command support 844 CONFIG_CMD_EXT4 * ext4 command support 845 CONFIG_CMD_SAVEENV saveenv 846 CONFIG_CMD_FDC * Floppy Disk Support 847 CONFIG_CMD_FAT * FAT command support 848 CONFIG_CMD_FDOS * Dos diskette Support 849 CONFIG_CMD_FLASH flinfo, erase, protect 850 CONFIG_CMD_FPGA FPGA device initialization support 851 CONFIG_CMD_FUSE * Device fuse support 852 CONFIG_CMD_GETTIME * Get time since boot 853 CONFIG_CMD_GO * the 'go' command (exec code) 854 CONFIG_CMD_GREPENV * search environment 855 CONFIG_CMD_HASH * calculate hash / digest 856 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control 857 CONFIG_CMD_I2C * I2C serial bus support 858 CONFIG_CMD_IDE * IDE harddisk support 859 CONFIG_CMD_IMI iminfo 860 CONFIG_CMD_IMLS List all images found in NOR flash 861 CONFIG_CMD_IMLS_NAND * List all images found in NAND flash 862 CONFIG_CMD_IMMAP * IMMR dump support 863 CONFIG_CMD_IMPORTENV * import an environment 864 CONFIG_CMD_INI * import data from an ini file into the env 865 CONFIG_CMD_IRQ * irqinfo 866 CONFIG_CMD_ITEST Integer/string test of 2 values 867 CONFIG_CMD_JFFS2 * JFFS2 Support 868 CONFIG_CMD_KGDB * kgdb 869 CONFIG_CMD_LDRINFO * ldrinfo (display Blackfin loader) 870 CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration 871 (169.254.*.*) 872 CONFIG_CMD_LOADB loadb 873 CONFIG_CMD_LOADS loads 874 CONFIG_CMD_MD5SUM * print md5 message digest 875 (requires CONFIG_CMD_MEMORY and CONFIG_MD5) 876 CONFIG_CMD_MEMINFO * Display detailed memory information 877 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base, 878 loop, loopw 879 CONFIG_CMD_MEMTEST * mtest 880 CONFIG_CMD_MISC Misc functions like sleep etc 881 CONFIG_CMD_MMC * MMC memory mapped support 882 CONFIG_CMD_MII * MII utility commands 883 CONFIG_CMD_MTDPARTS * MTD partition support 884 CONFIG_CMD_NAND * NAND support 885 CONFIG_CMD_NET bootp, tftpboot, rarpboot 886 CONFIG_CMD_NFS NFS support 887 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands 888 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command 889 CONFIG_CMD_PCI * pciinfo 890 CONFIG_CMD_PCMCIA * PCMCIA support 891 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network 892 host 893 CONFIG_CMD_PORTIO * Port I/O 894 CONFIG_CMD_READ * Read raw data from partition 895 CONFIG_CMD_REGINFO * Register dump 896 CONFIG_CMD_RUN run command in env variable 897 CONFIG_CMD_SANDBOX * sb command to access sandbox features 898 CONFIG_CMD_SAVES * save S record dump 899 CONFIG_CMD_SCSI * SCSI Support 900 CONFIG_CMD_SDRAM * print SDRAM configuration information 901 (requires CONFIG_CMD_I2C) 902 CONFIG_CMD_SETGETDCR Support for DCR Register access 903 (4xx only) 904 CONFIG_CMD_SF * Read/write/erase SPI NOR flash 905 CONFIG_CMD_SHA1SUM * print sha1 memory digest 906 (requires CONFIG_CMD_MEMORY) 907 CONFIG_CMD_SOFTSWITCH * Soft switch setting command for BF60x 908 CONFIG_CMD_SOURCE "source" command Support 909 CONFIG_CMD_SPI * SPI serial bus support 910 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode 911 CONFIG_CMD_TFTPPUT * TFTP put command (upload) 912 CONFIG_CMD_TIME * run command and report execution time (ARM specific) 913 CONFIG_CMD_TIMER * access to the system tick timer 914 CONFIG_CMD_USB * USB support 915 CONFIG_CMD_CDP * Cisco Discover Protocol support 916 CONFIG_CMD_MFSL * Microblaze FSL support 917 CONFIG_CMD_XIMG Load part of Multi Image 918 919 920 EXAMPLE: If you want all functions except of network 921 support you can write: 922 923 #include "config_cmd_all.h" 924 #undef CONFIG_CMD_NET 925 926 Other Commands: 927 fdt (flattened device tree) command: CONFIG_OF_LIBFDT 928 929 Note: Don't enable the "icache" and "dcache" commands 930 (configuration option CONFIG_CMD_CACHE) unless you know 931 what you (and your U-Boot users) are doing. Data 932 cache cannot be enabled on systems like the 8xx or 933 8260 (where accesses to the IMMR region must be 934 uncached), and it cannot be disabled on all other 935 systems where we (mis-) use the data cache to hold an 936 initial stack and some data. 937 938 939 XXX - this list needs to get updated! 940 941- Regular expression support: 942 CONFIG_REGEX 943 If this variable is defined, U-Boot is linked against 944 the SLRE (Super Light Regular Expression) library, 945 which adds regex support to some commands, as for 946 example "env grep" and "setexpr". 947 948- Device tree: 949 CONFIG_OF_CONTROL 950 If this variable is defined, U-Boot will use a device tree 951 to configure its devices, instead of relying on statically 952 compiled #defines in the board file. This option is 953 experimental and only available on a few boards. The device 954 tree is available in the global data as gd->fdt_blob. 955 956 U-Boot needs to get its device tree from somewhere. This can 957 be done using one of the two options below: 958 959 CONFIG_OF_EMBED 960 If this variable is defined, U-Boot will embed a device tree 961 binary in its image. This device tree file should be in the 962 board directory and called <soc>-<board>.dts. The binary file 963 is then picked up in board_init_f() and made available through 964 the global data structure as gd->blob. 965 966 CONFIG_OF_SEPARATE 967 If this variable is defined, U-Boot will build a device tree 968 binary. It will be called u-boot.dtb. Architecture-specific 969 code will locate it at run-time. Generally this works by: 970 971 cat u-boot.bin u-boot.dtb >image.bin 972 973 and in fact, U-Boot does this for you, creating a file called 974 u-boot-dtb.bin which is useful in the common case. You can 975 still use the individual files if you need something more 976 exotic. 977 978- Watchdog: 979 CONFIG_WATCHDOG 980 If this variable is defined, it enables watchdog 981 support for the SoC. There must be support in the SoC 982 specific code for a watchdog. For the 8xx and 8260 983 CPUs, the SIU Watchdog feature is enabled in the SYPCR 984 register. When supported for a specific SoC is 985 available, then no further board specific code should 986 be needed to use it. 987 988 CONFIG_HW_WATCHDOG 989 When using a watchdog circuitry external to the used 990 SoC, then define this variable and provide board 991 specific code for the "hw_watchdog_reset" function. 992 993- U-Boot Version: 994 CONFIG_VERSION_VARIABLE 995 If this variable is defined, an environment variable 996 named "ver" is created by U-Boot showing the U-Boot 997 version as printed by the "version" command. 998 Any change to this variable will be reverted at the 999 next reset. 1000 1001- Real-Time Clock: 1002 1003 When CONFIG_CMD_DATE is selected, the type of the RTC 1004 has to be selected, too. Define exactly one of the 1005 following options: 1006 1007 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx 1008 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC 1009 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC 1010 CONFIG_RTC_MC146818 - use MC146818 RTC 1011 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC 1012 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC 1013 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC 1014 CONFIG_RTC_DS164x - use Dallas DS164x RTC 1015 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC 1016 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC 1017 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337 1018 CONFIG_SYS_RV3029_TCR - enable trickle charger on 1019 RV3029 RTC. 1020 1021 Note that if the RTC uses I2C, then the I2C interface 1022 must also be configured. See I2C Support, below. 1023 1024- GPIO Support: 1025 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO 1026 CONFIG_PCA953X_INFO - enable pca953x info command 1027 1028 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of 1029 chip-ngpio pairs that tell the PCA953X driver the number of 1030 pins supported by a particular chip. 1031 1032 Note that if the GPIO device uses I2C, then the I2C interface 1033 must also be configured. See I2C Support, below. 1034 1035- Timestamp Support: 1036 1037 When CONFIG_TIMESTAMP is selected, the timestamp 1038 (date and time) of an image is printed by image 1039 commands like bootm or iminfo. This option is 1040 automatically enabled when you select CONFIG_CMD_DATE . 1041 1042- Partition Labels (disklabels) Supported: 1043 Zero or more of the following: 1044 CONFIG_MAC_PARTITION Apple's MacOS partition table. 1045 CONFIG_DOS_PARTITION MS Dos partition table, traditional on the 1046 Intel architecture, USB sticks, etc. 1047 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc. 1048 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the 1049 bootloader. Note 2TB partition limit; see 1050 disk/part_efi.c 1051 CONFIG_MTD_PARTITIONS Memory Technology Device partition table. 1052 1053 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or 1054 CONFIG_CMD_SCSI) you must configure support for at 1055 least one non-MTD partition type as well. 1056 1057- IDE Reset method: 1058 CONFIG_IDE_RESET_ROUTINE - this is defined in several 1059 board configurations files but used nowhere! 1060 1061 CONFIG_IDE_RESET - is this is defined, IDE Reset will 1062 be performed by calling the function 1063 ide_set_reset(int reset) 1064 which has to be defined in a board specific file 1065 1066- ATAPI Support: 1067 CONFIG_ATAPI 1068 1069 Set this to enable ATAPI support. 1070 1071- LBA48 Support 1072 CONFIG_LBA48 1073 1074 Set this to enable support for disks larger than 137GB 1075 Also look at CONFIG_SYS_64BIT_LBA. 1076 Whithout these , LBA48 support uses 32bit variables and will 'only' 1077 support disks up to 2.1TB. 1078 1079 CONFIG_SYS_64BIT_LBA: 1080 When enabled, makes the IDE subsystem use 64bit sector addresses. 1081 Default is 32bit. 1082 1083- SCSI Support: 1084 At the moment only there is only support for the 1085 SYM53C8XX SCSI controller; define 1086 CONFIG_SCSI_SYM53C8XX to enable it. 1087 1088 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and 1089 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID * 1090 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the 1091 maximum numbers of LUNs, SCSI ID's and target 1092 devices. 1093 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz) 1094 1095 The environment variable 'scsidevs' is set to the number of 1096 SCSI devices found during the last scan. 1097 1098- NETWORK Support (PCI): 1099 CONFIG_E1000 1100 Support for Intel 8254x/8257x gigabit chips. 1101 1102 CONFIG_E1000_SPI 1103 Utility code for direct access to the SPI bus on Intel 8257x. 1104 This does not do anything useful unless you set at least one 1105 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC. 1106 1107 CONFIG_E1000_SPI_GENERIC 1108 Allow generic access to the SPI bus on the Intel 8257x, for 1109 example with the "sspi" command. 1110 1111 CONFIG_CMD_E1000 1112 Management command for E1000 devices. When used on devices 1113 with SPI support you can reprogram the EEPROM from U-Boot. 1114 1115 CONFIG_E1000_FALLBACK_MAC 1116 default MAC for empty EEPROM after production. 1117 1118 CONFIG_EEPRO100 1119 Support for Intel 82557/82559/82559ER chips. 1120 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM 1121 write routine for first time initialisation. 1122 1123 CONFIG_TULIP 1124 Support for Digital 2114x chips. 1125 Optional CONFIG_TULIP_SELECT_MEDIA for board specific 1126 modem chip initialisation (KS8761/QS6611). 1127 1128 CONFIG_NATSEMI 1129 Support for National dp83815 chips. 1130 1131 CONFIG_NS8382X 1132 Support for National dp8382[01] gigabit chips. 1133 1134- NETWORK Support (other): 1135 1136 CONFIG_DRIVER_AT91EMAC 1137 Support for AT91RM9200 EMAC. 1138 1139 CONFIG_RMII 1140 Define this to use reduced MII inteface 1141 1142 CONFIG_DRIVER_AT91EMAC_QUIET 1143 If this defined, the driver is quiet. 1144 The driver doen't show link status messages. 1145 1146 CONFIG_CALXEDA_XGMAC 1147 Support for the Calxeda XGMAC device 1148 1149 CONFIG_LAN91C96 1150 Support for SMSC's LAN91C96 chips. 1151 1152 CONFIG_LAN91C96_BASE 1153 Define this to hold the physical address 1154 of the LAN91C96's I/O space 1155 1156 CONFIG_LAN91C96_USE_32_BIT 1157 Define this to enable 32 bit addressing 1158 1159 CONFIG_SMC91111 1160 Support for SMSC's LAN91C111 chip 1161 1162 CONFIG_SMC91111_BASE 1163 Define this to hold the physical address 1164 of the device (I/O space) 1165 1166 CONFIG_SMC_USE_32_BIT 1167 Define this if data bus is 32 bits 1168 1169 CONFIG_SMC_USE_IOFUNCS 1170 Define this to use i/o functions instead of macros 1171 (some hardware wont work with macros) 1172 1173 CONFIG_DRIVER_TI_EMAC 1174 Support for davinci emac 1175 1176 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT 1177 Define this if you have more then 3 PHYs. 1178 1179 CONFIG_FTGMAC100 1180 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet 1181 1182 CONFIG_FTGMAC100_EGIGA 1183 Define this to use GE link update with gigabit PHY. 1184 Define this if FTGMAC100 is connected to gigabit PHY. 1185 If your system has 10/100 PHY only, it might not occur 1186 wrong behavior. Because PHY usually return timeout or 1187 useless data when polling gigabit status and gigabit 1188 control registers. This behavior won't affect the 1189 correctnessof 10/100 link speed update. 1190 1191 CONFIG_SMC911X 1192 Support for SMSC's LAN911x and LAN921x chips 1193 1194 CONFIG_SMC911X_BASE 1195 Define this to hold the physical address 1196 of the device (I/O space) 1197 1198 CONFIG_SMC911X_32_BIT 1199 Define this if data bus is 32 bits 1200 1201 CONFIG_SMC911X_16_BIT 1202 Define this if data bus is 16 bits. If your processor 1203 automatically converts one 32 bit word to two 16 bit 1204 words you may also try CONFIG_SMC911X_32_BIT. 1205 1206 CONFIG_SH_ETHER 1207 Support for Renesas on-chip Ethernet controller 1208 1209 CONFIG_SH_ETHER_USE_PORT 1210 Define the number of ports to be used 1211 1212 CONFIG_SH_ETHER_PHY_ADDR 1213 Define the ETH PHY's address 1214 1215 CONFIG_SH_ETHER_CACHE_WRITEBACK 1216 If this option is set, the driver enables cache flush. 1217 1218- TPM Support: 1219 CONFIG_TPM 1220 Support TPM devices. 1221 1222 CONFIG_TPM_TIS_I2C 1223 Support for i2c bus TPM devices. Only one device 1224 per system is supported at this time. 1225 1226 CONFIG_TPM_TIS_I2C_BUS_NUMBER 1227 Define the the i2c bus number for the TPM device 1228 1229 CONFIG_TPM_TIS_I2C_SLAVE_ADDRESS 1230 Define the TPM's address on the i2c bus 1231 1232 CONFIG_TPM_TIS_I2C_BURST_LIMITATION 1233 Define the burst count bytes upper limit 1234 1235 CONFIG_TPM_ATMEL_TWI 1236 Support for Atmel TWI TPM device. Requires I2C support. 1237 1238 CONFIG_TPM_TIS_LPC 1239 Support for generic parallel port TPM devices. Only one device 1240 per system is supported at this time. 1241 1242 CONFIG_TPM_TIS_BASE_ADDRESS 1243 Base address where the generic TPM device is mapped 1244 to. Contemporary x86 systems usually map it at 1245 0xfed40000. 1246 1247 CONFIG_CMD_TPM 1248 Add tpm monitor functions. 1249 Requires CONFIG_TPM. If CONFIG_TPM_AUTH_SESSIONS is set, also 1250 provides monitor access to authorized functions. 1251 1252 CONFIG_TPM 1253 Define this to enable the TPM support library which provides 1254 functional interfaces to some TPM commands. 1255 Requires support for a TPM device. 1256 1257 CONFIG_TPM_AUTH_SESSIONS 1258 Define this to enable authorized functions in the TPM library. 1259 Requires CONFIG_TPM and CONFIG_SHA1. 1260 1261- USB Support: 1262 At the moment only the UHCI host controller is 1263 supported (PIP405, MIP405, MPC5200); define 1264 CONFIG_USB_UHCI to enable it. 1265 define CONFIG_USB_KEYBOARD to enable the USB Keyboard 1266 and define CONFIG_USB_STORAGE to enable the USB 1267 storage devices. 1268 Note: 1269 Supported are USB Keyboards and USB Floppy drives 1270 (TEAC FD-05PUB). 1271 MPC5200 USB requires additional defines: 1272 CONFIG_USB_CLOCK 1273 for 528 MHz Clock: 0x0001bbbb 1274 CONFIG_PSC3_USB 1275 for USB on PSC3 1276 CONFIG_USB_CONFIG 1277 for differential drivers: 0x00001000 1278 for single ended drivers: 0x00005000 1279 for differential drivers on PSC3: 0x00000100 1280 for single ended drivers on PSC3: 0x00004100 1281 CONFIG_SYS_USB_EVENT_POLL 1282 May be defined to allow interrupt polling 1283 instead of using asynchronous interrupts 1284 1285 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the 1286 txfilltuning field in the EHCI controller on reset. 1287 1288 CONFIG_USB_HUB_MIN_POWER_ON_DELAY defines the minimum 1289 interval for usb hub power-on delay.(minimum 100msec) 1290 1291- USB Device: 1292 Define the below if you wish to use the USB console. 1293 Once firmware is rebuilt from a serial console issue the 1294 command "setenv stdin usbtty; setenv stdout usbtty" and 1295 attach your USB cable. The Unix command "dmesg" should print 1296 it has found a new device. The environment variable usbtty 1297 can be set to gserial or cdc_acm to enable your device to 1298 appear to a USB host as a Linux gserial device or a 1299 Common Device Class Abstract Control Model serial device. 1300 If you select usbtty = gserial you should be able to enumerate 1301 a Linux host by 1302 # modprobe usbserial vendor=0xVendorID product=0xProductID 1303 else if using cdc_acm, simply setting the environment 1304 variable usbtty to be cdc_acm should suffice. The following 1305 might be defined in YourBoardName.h 1306 1307 CONFIG_USB_DEVICE 1308 Define this to build a UDC device 1309 1310 CONFIG_USB_TTY 1311 Define this to have a tty type of device available to 1312 talk to the UDC device 1313 1314 CONFIG_USBD_HS 1315 Define this to enable the high speed support for usb 1316 device and usbtty. If this feature is enabled, a routine 1317 int is_usbd_high_speed(void) 1318 also needs to be defined by the driver to dynamically poll 1319 whether the enumeration has succeded at high speed or full 1320 speed. 1321 1322 CONFIG_SYS_CONSOLE_IS_IN_ENV 1323 Define this if you want stdin, stdout &/or stderr to 1324 be set to usbtty. 1325 1326 mpc8xx: 1327 CONFIG_SYS_USB_EXTC_CLK 0xBLAH 1328 Derive USB clock from external clock "blah" 1329 - CONFIG_SYS_USB_EXTC_CLK 0x02 1330 1331 CONFIG_SYS_USB_BRG_CLK 0xBLAH 1332 Derive USB clock from brgclk 1333 - CONFIG_SYS_USB_BRG_CLK 0x04 1334 1335 If you have a USB-IF assigned VendorID then you may wish to 1336 define your own vendor specific values either in BoardName.h 1337 or directly in usbd_vendor_info.h. If you don't define 1338 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME, 1339 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot 1340 should pretend to be a Linux device to it's target host. 1341 1342 CONFIG_USBD_MANUFACTURER 1343 Define this string as the name of your company for 1344 - CONFIG_USBD_MANUFACTURER "my company" 1345 1346 CONFIG_USBD_PRODUCT_NAME 1347 Define this string as the name of your product 1348 - CONFIG_USBD_PRODUCT_NAME "acme usb device" 1349 1350 CONFIG_USBD_VENDORID 1351 Define this as your assigned Vendor ID from the USB 1352 Implementors Forum. This *must* be a genuine Vendor ID 1353 to avoid polluting the USB namespace. 1354 - CONFIG_USBD_VENDORID 0xFFFF 1355 1356 CONFIG_USBD_PRODUCTID 1357 Define this as the unique Product ID 1358 for your device 1359 - CONFIG_USBD_PRODUCTID 0xFFFF 1360 1361- ULPI Layer Support: 1362 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via 1363 the generic ULPI layer. The generic layer accesses the ULPI PHY 1364 via the platform viewport, so you need both the genric layer and 1365 the viewport enabled. Currently only Chipidea/ARC based 1366 viewport is supported. 1367 To enable the ULPI layer support, define CONFIG_USB_ULPI and 1368 CONFIG_USB_ULPI_VIEWPORT in your board configuration file. 1369 If your ULPI phy needs a different reference clock than the 1370 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to 1371 the appropriate value in Hz. 1372 1373- MMC Support: 1374 The MMC controller on the Intel PXA is supported. To 1375 enable this define CONFIG_MMC. The MMC can be 1376 accessed from the boot prompt by mapping the device 1377 to physical memory similar to flash. Command line is 1378 enabled with CONFIG_CMD_MMC. The MMC driver also works with 1379 the FAT fs. This is enabled with CONFIG_CMD_FAT. 1380 1381 CONFIG_SH_MMCIF 1382 Support for Renesas on-chip MMCIF controller 1383 1384 CONFIG_SH_MMCIF_ADDR 1385 Define the base address of MMCIF registers 1386 1387 CONFIG_SH_MMCIF_CLK 1388 Define the clock frequency for MMCIF 1389 1390- USB Device Firmware Update (DFU) class support: 1391 CONFIG_DFU_FUNCTION 1392 This enables the USB portion of the DFU USB class 1393 1394 CONFIG_CMD_DFU 1395 This enables the command "dfu" which is used to have 1396 U-Boot create a DFU class device via USB. This command 1397 requires that the "dfu_alt_info" environment variable be 1398 set and define the alt settings to expose to the host. 1399 1400 CONFIG_DFU_MMC 1401 This enables support for exposing (e)MMC devices via DFU. 1402 1403 CONFIG_DFU_NAND 1404 This enables support for exposing NAND devices via DFU. 1405 1406 CONFIG_SYS_DFU_DATA_BUF_SIZE 1407 Dfu transfer uses a buffer before writing data to the 1408 raw storage device. Make the size (in bytes) of this buffer 1409 configurable. The size of this buffer is also configurable 1410 through the "dfu_bufsiz" environment variable. 1411 1412 CONFIG_SYS_DFU_MAX_FILE_SIZE 1413 When updating files rather than the raw storage device, 1414 we use a static buffer to copy the file into and then write 1415 the buffer once we've been given the whole file. Define 1416 this to the maximum filesize (in bytes) for the buffer. 1417 Default is 4 MiB if undefined. 1418 1419- Journaling Flash filesystem support: 1420 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE, 1421 CONFIG_JFFS2_NAND_DEV 1422 Define these for a default partition on a NAND device 1423 1424 CONFIG_SYS_JFFS2_FIRST_SECTOR, 1425 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS 1426 Define these for a default partition on a NOR device 1427 1428 CONFIG_SYS_JFFS_CUSTOM_PART 1429 Define this to create an own partition. You have to provide a 1430 function struct part_info* jffs2_part_info(int part_num) 1431 1432 If you define only one JFFS2 partition you may also want to 1433 #define CONFIG_SYS_JFFS_SINGLE_PART 1 1434 to disable the command chpart. This is the default when you 1435 have not defined a custom partition 1436 1437- FAT(File Allocation Table) filesystem write function support: 1438 CONFIG_FAT_WRITE 1439 1440 Define this to enable support for saving memory data as a 1441 file in FAT formatted partition. 1442 1443 This will also enable the command "fatwrite" enabling the 1444 user to write files to FAT. 1445 1446CBFS (Coreboot Filesystem) support 1447 CONFIG_CMD_CBFS 1448 1449 Define this to enable support for reading from a Coreboot 1450 filesystem. Available commands are cbfsinit, cbfsinfo, cbfsls 1451 and cbfsload. 1452 1453- Keyboard Support: 1454 CONFIG_ISA_KEYBOARD 1455 1456 Define this to enable standard (PC-Style) keyboard 1457 support 1458 1459 CONFIG_I8042_KBD 1460 Standard PC keyboard driver with US (is default) and 1461 GERMAN key layout (switch via environment 'keymap=de') support. 1462 Export function i8042_kbd_init, i8042_tstc and i8042_getc 1463 for cfb_console. Supports cursor blinking. 1464 1465 CONFIG_CROS_EC_KEYB 1466 Enables a Chrome OS keyboard using the CROS_EC interface. 1467 This uses CROS_EC to communicate with a second microcontroller 1468 which provides key scans on request. 1469 1470- Video support: 1471 CONFIG_VIDEO 1472 1473 Define this to enable video support (for output to 1474 video). 1475 1476 CONFIG_VIDEO_CT69000 1477 1478 Enable Chips & Technologies 69000 Video chip 1479 1480 CONFIG_VIDEO_SMI_LYNXEM 1481 Enable Silicon Motion SMI 712/710/810 Video chip. The 1482 video output is selected via environment 'videoout' 1483 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is 1484 assumed. 1485 1486 For the CT69000 and SMI_LYNXEM drivers, videomode is 1487 selected via environment 'videomode'. Two different ways 1488 are possible: 1489 - "videomode=num" 'num' is a standard LiLo mode numbers. 1490 Following standard modes are supported (* is default): 1491 1492 Colors 640x480 800x600 1024x768 1152x864 1280x1024 1493 -------------+--------------------------------------------- 1494 8 bits | 0x301* 0x303 0x305 0x161 0x307 1495 15 bits | 0x310 0x313 0x316 0x162 0x319 1496 16 bits | 0x311 0x314 0x317 0x163 0x31A 1497 24 bits | 0x312 0x315 0x318 ? 0x31B 1498 -------------+--------------------------------------------- 1499 (i.e. setenv videomode 317; saveenv; reset;) 1500 1501 - "videomode=bootargs" all the video parameters are parsed 1502 from the bootargs. (See drivers/video/videomodes.c) 1503 1504 1505 CONFIG_VIDEO_SED13806 1506 Enable Epson SED13806 driver. This driver supports 8bpp 1507 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP 1508 or CONFIG_VIDEO_SED13806_16BPP 1509 1510 CONFIG_FSL_DIU_FB 1511 Enable the Freescale DIU video driver. Reference boards for 1512 SOCs that have a DIU should define this macro to enable DIU 1513 support, and should also define these other macros: 1514 1515 CONFIG_SYS_DIU_ADDR 1516 CONFIG_VIDEO 1517 CONFIG_CMD_BMP 1518 CONFIG_CFB_CONSOLE 1519 CONFIG_VIDEO_SW_CURSOR 1520 CONFIG_VGA_AS_SINGLE_DEVICE 1521 CONFIG_VIDEO_LOGO 1522 CONFIG_VIDEO_BMP_LOGO 1523 1524 The DIU driver will look for the 'video-mode' environment 1525 variable, and if defined, enable the DIU as a console during 1526 boot. See the documentation file README.video for a 1527 description of this variable. 1528 1529 CONFIG_VIDEO_VGA 1530 1531 Enable the VGA video / BIOS for x86. The alternative if you 1532 are using coreboot is to use the coreboot frame buffer 1533 driver. 1534 1535 1536- Keyboard Support: 1537 CONFIG_KEYBOARD 1538 1539 Define this to enable a custom keyboard support. 1540 This simply calls drv_keyboard_init() which must be 1541 defined in your board-specific files. 1542 The only board using this so far is RBC823. 1543 1544- LCD Support: CONFIG_LCD 1545 1546 Define this to enable LCD support (for output to LCD 1547 display); also select one of the supported displays 1548 by defining one of these: 1549 1550 CONFIG_ATMEL_LCD: 1551 1552 HITACHI TX09D70VM1CCA, 3.5", 240x320. 1553 1554 CONFIG_NEC_NL6448AC33: 1555 1556 NEC NL6448AC33-18. Active, color, single scan. 1557 1558 CONFIG_NEC_NL6448BC20 1559 1560 NEC NL6448BC20-08. 6.5", 640x480. 1561 Active, color, single scan. 1562 1563 CONFIG_NEC_NL6448BC33_54 1564 1565 NEC NL6448BC33-54. 10.4", 640x480. 1566 Active, color, single scan. 1567 1568 CONFIG_SHARP_16x9 1569 1570 Sharp 320x240. Active, color, single scan. 1571 It isn't 16x9, and I am not sure what it is. 1572 1573 CONFIG_SHARP_LQ64D341 1574 1575 Sharp LQ64D341 display, 640x480. 1576 Active, color, single scan. 1577 1578 CONFIG_HLD1045 1579 1580 HLD1045 display, 640x480. 1581 Active, color, single scan. 1582 1583 CONFIG_OPTREX_BW 1584 1585 Optrex CBL50840-2 NF-FW 99 22 M5 1586 or 1587 Hitachi LMG6912RPFC-00T 1588 or 1589 Hitachi SP14Q002 1590 1591 320x240. Black & white. 1592 1593 Normally display is black on white background; define 1594 CONFIG_SYS_WHITE_ON_BLACK to get it inverted. 1595 1596 CONFIG_LCD_ALIGNMENT 1597 1598 Normally the LCD is page-aligned (tyically 4KB). If this is 1599 defined then the LCD will be aligned to this value instead. 1600 For ARM it is sometimes useful to use MMU_SECTION_SIZE 1601 here, since it is cheaper to change data cache settings on 1602 a per-section basis. 1603 1604 CONFIG_CONSOLE_SCROLL_LINES 1605 1606 When the console need to be scrolled, this is the number of 1607 lines to scroll by. It defaults to 1. Increasing this makes 1608 the console jump but can help speed up operation when scrolling 1609 is slow. 1610 1611 CONFIG_LCD_BMP_RLE8 1612 1613 Support drawing of RLE8-compressed bitmaps on the LCD. 1614 1615 CONFIG_I2C_EDID 1616 1617 Enables an 'i2c edid' command which can read EDID 1618 information over I2C from an attached LCD display. 1619 1620- Splash Screen Support: CONFIG_SPLASH_SCREEN 1621 1622 If this option is set, the environment is checked for 1623 a variable "splashimage". If found, the usual display 1624 of logo, copyright and system information on the LCD 1625 is suppressed and the BMP image at the address 1626 specified in "splashimage" is loaded instead. The 1627 console is redirected to the "nulldev", too. This 1628 allows for a "silent" boot where a splash screen is 1629 loaded very quickly after power-on. 1630 1631 CONFIG_SPLASHIMAGE_GUARD 1632 1633 If this option is set, then U-Boot will prevent the environment 1634 variable "splashimage" from being set to a problematic address 1635 (see README.displaying-bmps and README.arm-unaligned-accesses). 1636 This option is useful for targets where, due to alignment 1637 restrictions, an improperly aligned BMP image will cause a data 1638 abort. If you think you will not have problems with unaligned 1639 accesses (for example because your toolchain prevents them) 1640 there is no need to set this option. 1641 1642 CONFIG_SPLASH_SCREEN_ALIGN 1643 1644 If this option is set the splash image can be freely positioned 1645 on the screen. Environment variable "splashpos" specifies the 1646 position as "x,y". If a positive number is given it is used as 1647 number of pixel from left/top. If a negative number is given it 1648 is used as number of pixel from right/bottom. You can also 1649 specify 'm' for centering the image. 1650 1651 Example: 1652 setenv splashpos m,m 1653 => image at center of screen 1654 1655 setenv splashpos 30,20 1656 => image at x = 30 and y = 20 1657 1658 setenv splashpos -10,m 1659 => vertically centered image 1660 at x = dspWidth - bmpWidth - 9 1661 1662- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP 1663 1664 If this option is set, additionally to standard BMP 1665 images, gzipped BMP images can be displayed via the 1666 splashscreen support or the bmp command. 1667 1668- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8 1669 1670 If this option is set, 8-bit RLE compressed BMP images 1671 can be displayed via the splashscreen support or the 1672 bmp command. 1673 1674- Do compresssing for memory range: 1675 CONFIG_CMD_ZIP 1676 1677 If this option is set, it would use zlib deflate method 1678 to compress the specified memory at its best effort. 1679 1680- Compression support: 1681 CONFIG_GZIP 1682 1683 Enabled by default to support gzip compressed images. 1684 1685 CONFIG_BZIP2 1686 1687 If this option is set, support for bzip2 compressed 1688 images is included. If not, only uncompressed and gzip 1689 compressed images are supported. 1690 1691 NOTE: the bzip2 algorithm requires a lot of RAM, so 1692 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should 1693 be at least 4MB. 1694 1695 CONFIG_LZMA 1696 1697 If this option is set, support for lzma compressed 1698 images is included. 1699 1700 Note: The LZMA algorithm adds between 2 and 4KB of code and it 1701 requires an amount of dynamic memory that is given by the 1702 formula: 1703 1704 (1846 + 768 << (lc + lp)) * sizeof(uint16) 1705 1706 Where lc and lp stand for, respectively, Literal context bits 1707 and Literal pos bits. 1708 1709 This value is upper-bounded by 14MB in the worst case. Anyway, 1710 for a ~4MB large kernel image, we have lc=3 and lp=0 for a 1711 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is 1712 a very small buffer. 1713 1714 Use the lzmainfo tool to determinate the lc and lp values and 1715 then calculate the amount of needed dynamic memory (ensuring 1716 the appropriate CONFIG_SYS_MALLOC_LEN value). 1717 1718 CONFIG_LZO 1719 1720 If this option is set, support for LZO compressed images 1721 is included. 1722 1723- MII/PHY support: 1724 CONFIG_PHY_ADDR 1725 1726 The address of PHY on MII bus. 1727 1728 CONFIG_PHY_CLOCK_FREQ (ppc4xx) 1729 1730 The clock frequency of the MII bus 1731 1732 CONFIG_PHY_GIGE 1733 1734 If this option is set, support for speed/duplex 1735 detection of gigabit PHY is included. 1736 1737 CONFIG_PHY_RESET_DELAY 1738 1739 Some PHY like Intel LXT971A need extra delay after 1740 reset before any MII register access is possible. 1741 For such PHY, set this option to the usec delay 1742 required. (minimum 300usec for LXT971A) 1743 1744 CONFIG_PHY_CMD_DELAY (ppc4xx) 1745 1746 Some PHY like Intel LXT971A need extra delay after 1747 command issued before MII status register can be read 1748 1749- Ethernet address: 1750 CONFIG_ETHADDR 1751 CONFIG_ETH1ADDR 1752 CONFIG_ETH2ADDR 1753 CONFIG_ETH3ADDR 1754 CONFIG_ETH4ADDR 1755 CONFIG_ETH5ADDR 1756 1757 Define a default value for Ethernet address to use 1758 for the respective Ethernet interface, in case this 1759 is not determined automatically. 1760 1761- IP address: 1762 CONFIG_IPADDR 1763 1764 Define a default value for the IP address to use for 1765 the default Ethernet interface, in case this is not 1766 determined through e.g. bootp. 1767 (Environment variable "ipaddr") 1768 1769- Server IP address: 1770 CONFIG_SERVERIP 1771 1772 Defines a default value for the IP address of a TFTP 1773 server to contact when using the "tftboot" command. 1774 (Environment variable "serverip") 1775 1776 CONFIG_KEEP_SERVERADDR 1777 1778 Keeps the server's MAC address, in the env 'serveraddr' 1779 for passing to bootargs (like Linux's netconsole option) 1780 1781- Gateway IP address: 1782 CONFIG_GATEWAYIP 1783 1784 Defines a default value for the IP address of the 1785 default router where packets to other networks are 1786 sent to. 1787 (Environment variable "gatewayip") 1788 1789- Subnet mask: 1790 CONFIG_NETMASK 1791 1792 Defines a default value for the subnet mask (or 1793 routing prefix) which is used to determine if an IP 1794 address belongs to the local subnet or needs to be 1795 forwarded through a router. 1796 (Environment variable "netmask") 1797 1798- Multicast TFTP Mode: 1799 CONFIG_MCAST_TFTP 1800 1801 Defines whether you want to support multicast TFTP as per 1802 rfc-2090; for example to work with atftp. Lets lots of targets 1803 tftp down the same boot image concurrently. Note: the Ethernet 1804 driver in use must provide a function: mcast() to join/leave a 1805 multicast group. 1806 1807- BOOTP Recovery Mode: 1808 CONFIG_BOOTP_RANDOM_DELAY 1809 1810 If you have many targets in a network that try to 1811 boot using BOOTP, you may want to avoid that all 1812 systems send out BOOTP requests at precisely the same 1813 moment (which would happen for instance at recovery 1814 from a power failure, when all systems will try to 1815 boot, thus flooding the BOOTP server. Defining 1816 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 1817 inserted before sending out BOOTP requests. The 1818 following delays are inserted then: 1819 1820 1st BOOTP request: delay 0 ... 1 sec 1821 2nd BOOTP request: delay 0 ... 2 sec 1822 3rd BOOTP request: delay 0 ... 4 sec 1823 4th and following 1824 BOOTP requests: delay 0 ... 8 sec 1825 1826- DHCP Advanced Options: 1827 You can fine tune the DHCP functionality by defining 1828 CONFIG_BOOTP_* symbols: 1829 1830 CONFIG_BOOTP_SUBNETMASK 1831 CONFIG_BOOTP_GATEWAY 1832 CONFIG_BOOTP_HOSTNAME 1833 CONFIG_BOOTP_NISDOMAIN 1834 CONFIG_BOOTP_BOOTPATH 1835 CONFIG_BOOTP_BOOTFILESIZE 1836 CONFIG_BOOTP_DNS 1837 CONFIG_BOOTP_DNS2 1838 CONFIG_BOOTP_SEND_HOSTNAME 1839 CONFIG_BOOTP_NTPSERVER 1840 CONFIG_BOOTP_TIMEOFFSET 1841 CONFIG_BOOTP_VENDOREX 1842 CONFIG_BOOTP_MAY_FAIL 1843 1844 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip 1845 environment variable, not the BOOTP server. 1846 1847 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found 1848 after the configured retry count, the call will fail 1849 instead of starting over. This can be used to fail over 1850 to Link-local IP address configuration if the DHCP server 1851 is not available. 1852 1853 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS 1854 serverip from a DHCP server, it is possible that more 1855 than one DNS serverip is offered to the client. 1856 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS 1857 serverip will be stored in the additional environment 1858 variable "dnsip2". The first DNS serverip is always 1859 stored in the variable "dnsip", when CONFIG_BOOTP_DNS 1860 is defined. 1861 1862 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable 1863 to do a dynamic update of a DNS server. To do this, they 1864 need the hostname of the DHCP requester. 1865 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content 1866 of the "hostname" environment variable is passed as 1867 option 12 to the DHCP server. 1868 1869 CONFIG_BOOTP_DHCP_REQUEST_DELAY 1870 1871 A 32bit value in microseconds for a delay between 1872 receiving a "DHCP Offer" and sending the "DHCP Request". 1873 This fixes a problem with certain DHCP servers that don't 1874 respond 100% of the time to a "DHCP request". E.g. On an 1875 AT91RM9200 processor running at 180MHz, this delay needed 1876 to be *at least* 15,000 usec before a Windows Server 2003 1877 DHCP server would reply 100% of the time. I recommend at 1878 least 50,000 usec to be safe. The alternative is to hope 1879 that one of the retries will be successful but note that 1880 the DHCP timeout and retry process takes a longer than 1881 this delay. 1882 1883 - Link-local IP address negotiation: 1884 Negotiate with other link-local clients on the local network 1885 for an address that doesn't require explicit configuration. 1886 This is especially useful if a DHCP server cannot be guaranteed 1887 to exist in all environments that the device must operate. 1888 1889 See doc/README.link-local for more information. 1890 1891 - CDP Options: 1892 CONFIG_CDP_DEVICE_ID 1893 1894 The device id used in CDP trigger frames. 1895 1896 CONFIG_CDP_DEVICE_ID_PREFIX 1897 1898 A two character string which is prefixed to the MAC address 1899 of the device. 1900 1901 CONFIG_CDP_PORT_ID 1902 1903 A printf format string which contains the ascii name of 1904 the port. Normally is set to "eth%d" which sets 1905 eth0 for the first Ethernet, eth1 for the second etc. 1906 1907 CONFIG_CDP_CAPABILITIES 1908 1909 A 32bit integer which indicates the device capabilities; 1910 0x00000010 for a normal host which does not forwards. 1911 1912 CONFIG_CDP_VERSION 1913 1914 An ascii string containing the version of the software. 1915 1916 CONFIG_CDP_PLATFORM 1917 1918 An ascii string containing the name of the platform. 1919 1920 CONFIG_CDP_TRIGGER 1921 1922 A 32bit integer sent on the trigger. 1923 1924 CONFIG_CDP_POWER_CONSUMPTION 1925 1926 A 16bit integer containing the power consumption of the 1927 device in .1 of milliwatts. 1928 1929 CONFIG_CDP_APPLIANCE_VLAN_TYPE 1930 1931 A byte containing the id of the VLAN. 1932 1933- Status LED: CONFIG_STATUS_LED 1934 1935 Several configurations allow to display the current 1936 status using a LED. For instance, the LED will blink 1937 fast while running U-Boot code, stop blinking as 1938 soon as a reply to a BOOTP request was received, and 1939 start blinking slow once the Linux kernel is running 1940 (supported by a status LED driver in the Linux 1941 kernel). Defining CONFIG_STATUS_LED enables this 1942 feature in U-Boot. 1943 1944- CAN Support: CONFIG_CAN_DRIVER 1945 1946 Defining CONFIG_CAN_DRIVER enables CAN driver support 1947 on those systems that support this (optional) 1948 feature, like the TQM8xxL modules. 1949 1950- I2C Support: CONFIG_SYS_I2C 1951 1952 This enable the NEW i2c subsystem, and will allow you to use 1953 i2c commands at the u-boot command line (as long as you set 1954 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c 1955 based realtime clock chips or other i2c devices. See 1956 common/cmd_i2c.c for a description of the command line 1957 interface. 1958 1959 ported i2c driver to the new framework: 1960 - drivers/i2c/soft_i2c.c: 1961 - activate first bus with CONFIG_SYS_I2C_SOFT define 1962 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE 1963 for defining speed and slave address 1964 - activate second bus with I2C_SOFT_DECLARATIONS2 define 1965 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2 1966 for defining speed and slave address 1967 - activate third bus with I2C_SOFT_DECLARATIONS3 define 1968 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3 1969 for defining speed and slave address 1970 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define 1971 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4 1972 for defining speed and slave address 1973 1974 - drivers/i2c/fsl_i2c.c: 1975 - activate i2c driver with CONFIG_SYS_I2C_FSL 1976 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register 1977 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and 1978 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first 1979 bus. 1980 - If your board supports a second fsl i2c bus, define 1981 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset 1982 CONFIG_SYS_FSL_I2C2_SPEED for the speed and 1983 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the 1984 second bus. 1985 1986 - drivers/i2c/tegra_i2c.c: 1987 - activate this driver with CONFIG_SYS_I2C_TEGRA 1988 - This driver adds 4 i2c buses with a fix speed from 1989 100000 and the slave addr 0! 1990 1991 - drivers/i2c/ppc4xx_i2c.c 1992 - activate this driver with CONFIG_SYS_I2C_PPC4XX 1993 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0 1994 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1 1995 1996 additional defines: 1997 1998 CONFIG_SYS_NUM_I2C_BUSES 1999 Hold the number of i2c busses you want to use. If you 2000 don't use/have i2c muxes on your i2c bus, this 2001 is equal to CONFIG_SYS_NUM_I2C_ADAPTERS, and you can 2002 omit this define. 2003 2004 CONFIG_SYS_I2C_DIRECT_BUS 2005 define this, if you don't use i2c muxes on your hardware. 2006 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can 2007 omit this define. 2008 2009 CONFIG_SYS_I2C_MAX_HOPS 2010 define how many muxes are maximal consecutively connected 2011 on one i2c bus. If you not use i2c muxes, omit this 2012 define. 2013 2014 CONFIG_SYS_I2C_BUSES 2015 hold a list of busses you want to use, only used if 2016 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example 2017 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and 2018 CONFIG_SYS_NUM_I2C_BUSES = 9: 2019 2020 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \ 2021 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \ 2022 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \ 2023 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \ 2024 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \ 2025 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \ 2026 {1, {I2C_NULL_HOP}}, \ 2027 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \ 2028 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \ 2029 } 2030 2031 which defines 2032 bus 0 on adapter 0 without a mux 2033 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1 2034 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2 2035 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3 2036 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4 2037 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5 2038 bus 6 on adapter 1 without a mux 2039 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1 2040 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2 2041 2042 If you do not have i2c muxes on your board, omit this define. 2043 2044- Legacy I2C Support: CONFIG_HARD_I2C 2045 2046 NOTE: It is intended to move drivers to CONFIG_SYS_I2C which 2047 provides the following compelling advantages: 2048 2049 - more than one i2c adapter is usable 2050 - approved multibus support 2051 - better i2c mux support 2052 2053 ** Please consider updating your I2C driver now. ** 2054 2055 These enable legacy I2C serial bus commands. Defining 2056 CONFIG_HARD_I2C will include the appropriate I2C driver 2057 for the selected CPU. 2058 2059 This will allow you to use i2c commands at the u-boot 2060 command line (as long as you set CONFIG_CMD_I2C in 2061 CONFIG_COMMANDS) and communicate with i2c based realtime 2062 clock chips. See common/cmd_i2c.c for a description of the 2063 command line interface. 2064 2065 CONFIG_HARD_I2C selects a hardware I2C controller. 2066 2067 There are several other quantities that must also be 2068 defined when you define CONFIG_HARD_I2C. 2069 2070 In both cases you will need to define CONFIG_SYS_I2C_SPEED 2071 to be the frequency (in Hz) at which you wish your i2c bus 2072 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie 2073 the CPU's i2c node address). 2074 2075 Now, the u-boot i2c code for the mpc8xx 2076 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node 2077 and so its address should therefore be cleared to 0 (See, 2078 eg, MPC823e User's Manual p.16-473). So, set 2079 CONFIG_SYS_I2C_SLAVE to 0. 2080 2081 CONFIG_SYS_I2C_INIT_MPC5XXX 2082 2083 When a board is reset during an i2c bus transfer 2084 chips might think that the current transfer is still 2085 in progress. Reset the slave devices by sending start 2086 commands until the slave device responds. 2087 2088 That's all that's required for CONFIG_HARD_I2C. 2089 2090 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT) 2091 then the following macros need to be defined (examples are 2092 from include/configs/lwmon.h): 2093 2094 I2C_INIT 2095 2096 (Optional). Any commands necessary to enable the I2C 2097 controller or configure ports. 2098 2099 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) 2100 2101 I2C_PORT 2102 2103 (Only for MPC8260 CPU). The I/O port to use (the code 2104 assumes both bits are on the same port). Valid values 2105 are 0..3 for ports A..D. 2106 2107 I2C_ACTIVE 2108 2109 The code necessary to make the I2C data line active 2110 (driven). If the data line is open collector, this 2111 define can be null. 2112 2113 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) 2114 2115 I2C_TRISTATE 2116 2117 The code necessary to make the I2C data line tri-stated 2118 (inactive). If the data line is open collector, this 2119 define can be null. 2120 2121 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) 2122 2123 I2C_READ 2124 2125 Code that returns true if the I2C data line is high, 2126 false if it is low. 2127 2128 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) 2129 2130 I2C_SDA(bit) 2131 2132 If <bit> is true, sets the I2C data line high. If it 2133 is false, it clears it (low). 2134 2135 eg: #define I2C_SDA(bit) \ 2136 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ 2137 else immr->im_cpm.cp_pbdat &= ~PB_SDA 2138 2139 I2C_SCL(bit) 2140 2141 If <bit> is true, sets the I2C clock line high. If it 2142 is false, it clears it (low). 2143 2144 eg: #define I2C_SCL(bit) \ 2145 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ 2146 else immr->im_cpm.cp_pbdat &= ~PB_SCL 2147 2148 I2C_DELAY 2149 2150 This delay is invoked four times per clock cycle so this 2151 controls the rate of data transfer. The data rate thus 2152 is 1 / (I2C_DELAY * 4). Often defined to be something 2153 like: 2154 2155 #define I2C_DELAY udelay(2) 2156 2157 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA 2158 2159 If your arch supports the generic GPIO framework (asm/gpio.h), 2160 then you may alternatively define the two GPIOs that are to be 2161 used as SCL / SDA. Any of the previous I2C_xxx macros will 2162 have GPIO-based defaults assigned to them as appropriate. 2163 2164 You should define these to the GPIO value as given directly to 2165 the generic GPIO functions. 2166 2167 CONFIG_SYS_I2C_INIT_BOARD 2168 2169 When a board is reset during an i2c bus transfer 2170 chips might think that the current transfer is still 2171 in progress. On some boards it is possible to access 2172 the i2c SCLK line directly, either by using the 2173 processor pin as a GPIO or by having a second pin 2174 connected to the bus. If this option is defined a 2175 custom i2c_init_board() routine in boards/xxx/board.c 2176 is run early in the boot sequence. 2177 2178 CONFIG_SYS_I2C_BOARD_LATE_INIT 2179 2180 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is 2181 defined a custom i2c_board_late_init() routine in 2182 boards/xxx/board.c is run AFTER the operations in i2c_init() 2183 is completed. This callpoint can be used to unreset i2c bus 2184 using CPU i2c controller register accesses for CPUs whose i2c 2185 controller provide such a method. It is called at the end of 2186 i2c_init() to allow i2c_init operations to setup the i2c bus 2187 controller on the CPU (e.g. setting bus speed & slave address). 2188 2189 CONFIG_I2CFAST (PPC405GP|PPC405EP only) 2190 2191 This option enables configuration of bi_iic_fast[] flags 2192 in u-boot bd_info structure based on u-boot environment 2193 variable "i2cfast". (see also i2cfast) 2194 2195 CONFIG_I2C_MULTI_BUS 2196 2197 This option allows the use of multiple I2C buses, each of which 2198 must have a controller. At any point in time, only one bus is 2199 active. To switch to a different bus, use the 'i2c dev' command. 2200 Note that bus numbering is zero-based. 2201 2202 CONFIG_SYS_I2C_NOPROBES 2203 2204 This option specifies a list of I2C devices that will be skipped 2205 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS 2206 is set, specify a list of bus-device pairs. Otherwise, specify 2207 a 1D array of device addresses 2208 2209 e.g. 2210 #undef CONFIG_I2C_MULTI_BUS 2211 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68} 2212 2213 will skip addresses 0x50 and 0x68 on a board with one I2C bus 2214 2215 #define CONFIG_I2C_MULTI_BUS 2216 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}} 2217 2218 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1 2219 2220 CONFIG_SYS_SPD_BUS_NUM 2221 2222 If defined, then this indicates the I2C bus number for DDR SPD. 2223 If not defined, then U-Boot assumes that SPD is on I2C bus 0. 2224 2225 CONFIG_SYS_RTC_BUS_NUM 2226 2227 If defined, then this indicates the I2C bus number for the RTC. 2228 If not defined, then U-Boot assumes that RTC is on I2C bus 0. 2229 2230 CONFIG_SYS_DTT_BUS_NUM 2231 2232 If defined, then this indicates the I2C bus number for the DTT. 2233 If not defined, then U-Boot assumes that DTT is on I2C bus 0. 2234 2235 CONFIG_SYS_I2C_DTT_ADDR: 2236 2237 If defined, specifies the I2C address of the DTT device. 2238 If not defined, then U-Boot uses predefined value for 2239 specified DTT device. 2240 2241 CONFIG_SOFT_I2C_READ_REPEATED_START 2242 2243 defining this will force the i2c_read() function in 2244 the soft_i2c driver to perform an I2C repeated start 2245 between writing the address pointer and reading the 2246 data. If this define is omitted the default behaviour 2247 of doing a stop-start sequence will be used. Most I2C 2248 devices can use either method, but some require one or 2249 the other. 2250 2251- SPI Support: CONFIG_SPI 2252 2253 Enables SPI driver (so far only tested with 2254 SPI EEPROM, also an instance works with Crystal A/D and 2255 D/As on the SACSng board) 2256 2257 CONFIG_SH_SPI 2258 2259 Enables the driver for SPI controller on SuperH. Currently 2260 only SH7757 is supported. 2261 2262 CONFIG_SPI_X 2263 2264 Enables extended (16-bit) SPI EEPROM addressing. 2265 (symmetrical to CONFIG_I2C_X) 2266 2267 CONFIG_SOFT_SPI 2268 2269 Enables a software (bit-bang) SPI driver rather than 2270 using hardware support. This is a general purpose 2271 driver that only requires three general I/O port pins 2272 (two outputs, one input) to function. If this is 2273 defined, the board configuration must define several 2274 SPI configuration items (port pins to use, etc). For 2275 an example, see include/configs/sacsng.h. 2276 2277 CONFIG_HARD_SPI 2278 2279 Enables a hardware SPI driver for general-purpose reads 2280 and writes. As with CONFIG_SOFT_SPI, the board configuration 2281 must define a list of chip-select function pointers. 2282 Currently supported on some MPC8xxx processors. For an 2283 example, see include/configs/mpc8349emds.h. 2284 2285 CONFIG_MXC_SPI 2286 2287 Enables the driver for the SPI controllers on i.MX and MXC 2288 SoCs. Currently i.MX31/35/51 are supported. 2289 2290- FPGA Support: CONFIG_FPGA 2291 2292 Enables FPGA subsystem. 2293 2294 CONFIG_FPGA_<vendor> 2295 2296 Enables support for specific chip vendors. 2297 (ALTERA, XILINX) 2298 2299 CONFIG_FPGA_<family> 2300 2301 Enables support for FPGA family. 2302 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX) 2303 2304 CONFIG_FPGA_COUNT 2305 2306 Specify the number of FPGA devices to support. 2307 2308 CONFIG_SYS_FPGA_PROG_FEEDBACK 2309 2310 Enable printing of hash marks during FPGA configuration. 2311 2312 CONFIG_SYS_FPGA_CHECK_BUSY 2313 2314 Enable checks on FPGA configuration interface busy 2315 status by the configuration function. This option 2316 will require a board or device specific function to 2317 be written. 2318 2319 CONFIG_FPGA_DELAY 2320 2321 If defined, a function that provides delays in the FPGA 2322 configuration driver. 2323 2324 CONFIG_SYS_FPGA_CHECK_CTRLC 2325 Allow Control-C to interrupt FPGA configuration 2326 2327 CONFIG_SYS_FPGA_CHECK_ERROR 2328 2329 Check for configuration errors during FPGA bitfile 2330 loading. For example, abort during Virtex II 2331 configuration if the INIT_B line goes low (which 2332 indicated a CRC error). 2333 2334 CONFIG_SYS_FPGA_WAIT_INIT 2335 2336 Maximum time to wait for the INIT_B line to deassert 2337 after PROB_B has been deasserted during a Virtex II 2338 FPGA configuration sequence. The default time is 500 2339 ms. 2340 2341 CONFIG_SYS_FPGA_WAIT_BUSY 2342 2343 Maximum time to wait for BUSY to deassert during 2344 Virtex II FPGA configuration. The default is 5 ms. 2345 2346 CONFIG_SYS_FPGA_WAIT_CONFIG 2347 2348 Time to wait after FPGA configuration. The default is 2349 200 ms. 2350 2351- Configuration Management: 2352 CONFIG_IDENT_STRING 2353 2354 If defined, this string will be added to the U-Boot 2355 version information (U_BOOT_VERSION) 2356 2357- Vendor Parameter Protection: 2358 2359 U-Boot considers the values of the environment 2360 variables "serial#" (Board Serial Number) and 2361 "ethaddr" (Ethernet Address) to be parameters that 2362 are set once by the board vendor / manufacturer, and 2363 protects these variables from casual modification by 2364 the user. Once set, these variables are read-only, 2365 and write or delete attempts are rejected. You can 2366 change this behaviour: 2367 2368 If CONFIG_ENV_OVERWRITE is #defined in your config 2369 file, the write protection for vendor parameters is 2370 completely disabled. Anybody can change or delete 2371 these parameters. 2372 2373 Alternatively, if you #define _both_ CONFIG_ETHADDR 2374 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 2375 Ethernet address is installed in the environment, 2376 which can be changed exactly ONCE by the user. [The 2377 serial# is unaffected by this, i. e. it remains 2378 read-only.] 2379 2380 The same can be accomplished in a more flexible way 2381 for any variable by configuring the type of access 2382 to allow for those variables in the ".flags" variable 2383 or define CONFIG_ENV_FLAGS_LIST_STATIC. 2384 2385- Protected RAM: 2386 CONFIG_PRAM 2387 2388 Define this variable to enable the reservation of 2389 "protected RAM", i. e. RAM which is not overwritten 2390 by U-Boot. Define CONFIG_PRAM to hold the number of 2391 kB you want to reserve for pRAM. You can overwrite 2392 this default value by defining an environment 2393 variable "pram" to the number of kB you want to 2394 reserve. Note that the board info structure will 2395 still show the full amount of RAM. If pRAM is 2396 reserved, a new environment variable "mem" will 2397 automatically be defined to hold the amount of 2398 remaining RAM in a form that can be passed as boot 2399 argument to Linux, for instance like that: 2400 2401 setenv bootargs ... mem=\${mem} 2402 saveenv 2403 2404 This way you can tell Linux not to use this memory, 2405 either, which results in a memory region that will 2406 not be affected by reboots. 2407 2408 *WARNING* If your board configuration uses automatic 2409 detection of the RAM size, you must make sure that 2410 this memory test is non-destructive. So far, the 2411 following board configurations are known to be 2412 "pRAM-clean": 2413 2414 IVMS8, IVML24, SPD8xx, TQM8xxL, 2415 HERMES, IP860, RPXlite, LWMON, 2416 FLAGADM, TQM8260 2417 2418- Access to physical memory region (> 4GB) 2419 Some basic support is provided for operations on memory not 2420 normally accessible to U-Boot - e.g. some architectures 2421 support access to more than 4GB of memory on 32-bit 2422 machines using physical address extension or similar. 2423 Define CONFIG_PHYSMEM to access this basic support, which 2424 currently only supports clearing the memory. 2425 2426- Error Recovery: 2427 CONFIG_PANIC_HANG 2428 2429 Define this variable to stop the system in case of a 2430 fatal error, so that you have to reset it manually. 2431 This is probably NOT a good idea for an embedded 2432 system where you want the system to reboot 2433 automatically as fast as possible, but it may be 2434 useful during development since you can try to debug 2435 the conditions that lead to the situation. 2436 2437 CONFIG_NET_RETRY_COUNT 2438 2439 This variable defines the number of retries for 2440 network operations like ARP, RARP, TFTP, or BOOTP 2441 before giving up the operation. If not defined, a 2442 default value of 5 is used. 2443 2444 CONFIG_ARP_TIMEOUT 2445 2446 Timeout waiting for an ARP reply in milliseconds. 2447 2448 CONFIG_NFS_TIMEOUT 2449 2450 Timeout in milliseconds used in NFS protocol. 2451 If you encounter "ERROR: Cannot umount" in nfs command, 2452 try longer timeout such as 2453 #define CONFIG_NFS_TIMEOUT 10000UL 2454 2455- Command Interpreter: 2456 CONFIG_AUTO_COMPLETE 2457 2458 Enable auto completion of commands using TAB. 2459 2460 Note that this feature has NOT been implemented yet 2461 for the "hush" shell. 2462 2463 2464 CONFIG_SYS_HUSH_PARSER 2465 2466 Define this variable to enable the "hush" shell (from 2467 Busybox) as command line interpreter, thus enabling 2468 powerful command line syntax like 2469 if...then...else...fi conditionals or `&&' and '||' 2470 constructs ("shell scripts"). 2471 2472 If undefined, you get the old, much simpler behaviour 2473 with a somewhat smaller memory footprint. 2474 2475 2476 CONFIG_SYS_PROMPT_HUSH_PS2 2477 2478 This defines the secondary prompt string, which is 2479 printed when the command interpreter needs more input 2480 to complete a command. Usually "> ". 2481 2482 Note: 2483 2484 In the current implementation, the local variables 2485 space and global environment variables space are 2486 separated. Local variables are those you define by 2487 simply typing `name=value'. To access a local 2488 variable later on, you have write `$name' or 2489 `${name}'; to execute the contents of a variable 2490 directly type `$name' at the command prompt. 2491 2492 Global environment variables are those you use 2493 setenv/printenv to work with. To run a command stored 2494 in such a variable, you need to use the run command, 2495 and you must not use the '$' sign to access them. 2496 2497 To store commands and special characters in a 2498 variable, please use double quotation marks 2499 surrounding the whole text of the variable, instead 2500 of the backslashes before semicolons and special 2501 symbols. 2502 2503- Commandline Editing and History: 2504 CONFIG_CMDLINE_EDITING 2505 2506 Enable editing and History functions for interactive 2507 commandline input operations 2508 2509- Default Environment: 2510 CONFIG_EXTRA_ENV_SETTINGS 2511 2512 Define this to contain any number of null terminated 2513 strings (variable = value pairs) that will be part of 2514 the default environment compiled into the boot image. 2515 2516 For example, place something like this in your 2517 board's config file: 2518 2519 #define CONFIG_EXTRA_ENV_SETTINGS \ 2520 "myvar1=value1\0" \ 2521 "myvar2=value2\0" 2522 2523 Warning: This method is based on knowledge about the 2524 internal format how the environment is stored by the 2525 U-Boot code. This is NOT an official, exported 2526 interface! Although it is unlikely that this format 2527 will change soon, there is no guarantee either. 2528 You better know what you are doing here. 2529 2530 Note: overly (ab)use of the default environment is 2531 discouraged. Make sure to check other ways to preset 2532 the environment like the "source" command or the 2533 boot command first. 2534 2535 CONFIG_ENV_VARS_UBOOT_CONFIG 2536 2537 Define this in order to add variables describing the 2538 U-Boot build configuration to the default environment. 2539 These will be named arch, cpu, board, vendor, and soc. 2540 2541 Enabling this option will cause the following to be defined: 2542 2543 - CONFIG_SYS_ARCH 2544 - CONFIG_SYS_CPU 2545 - CONFIG_SYS_BOARD 2546 - CONFIG_SYS_VENDOR 2547 - CONFIG_SYS_SOC 2548 2549 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG 2550 2551 Define this in order to add variables describing certain 2552 run-time determined information about the hardware to the 2553 environment. These will be named board_name, board_rev. 2554 2555 CONFIG_DELAY_ENVIRONMENT 2556 2557 Normally the environment is loaded when the board is 2558 intialised so that it is available to U-Boot. This inhibits 2559 that so that the environment is not available until 2560 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL 2561 this is instead controlled by the value of 2562 /config/load-environment. 2563 2564- DataFlash Support: 2565 CONFIG_HAS_DATAFLASH 2566 2567 Defining this option enables DataFlash features and 2568 allows to read/write in Dataflash via the standard 2569 commands cp, md... 2570 2571- Serial Flash support 2572 CONFIG_CMD_SF 2573 2574 Defining this option enables SPI flash commands 2575 'sf probe/read/write/erase/update'. 2576 2577 Usage requires an initial 'probe' to define the serial 2578 flash parameters, followed by read/write/erase/update 2579 commands. 2580 2581 The following defaults may be provided by the platform 2582 to handle the common case when only a single serial 2583 flash is present on the system. 2584 2585 CONFIG_SF_DEFAULT_BUS Bus identifier 2586 CONFIG_SF_DEFAULT_CS Chip-select 2587 CONFIG_SF_DEFAULT_MODE (see include/spi.h) 2588 CONFIG_SF_DEFAULT_SPEED in Hz 2589 2590 CONFIG_CMD_SF_TEST 2591 2592 Define this option to include a destructive SPI flash 2593 test ('sf test'). 2594 2595 CONFIG_SPI_FLASH_BAR Ban/Extended Addr Reg 2596 2597 Define this option to use the Bank addr/Extended addr 2598 support on SPI flashes which has size > 16Mbytes. 2599 2600- SystemACE Support: 2601 CONFIG_SYSTEMACE 2602 2603 Adding this option adds support for Xilinx SystemACE 2604 chips attached via some sort of local bus. The address 2605 of the chip must also be defined in the 2606 CONFIG_SYS_SYSTEMACE_BASE macro. For example: 2607 2608 #define CONFIG_SYSTEMACE 2609 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000 2610 2611 When SystemACE support is added, the "ace" device type 2612 becomes available to the fat commands, i.e. fatls. 2613 2614- TFTP Fixed UDP Port: 2615 CONFIG_TFTP_PORT 2616 2617 If this is defined, the environment variable tftpsrcp 2618 is used to supply the TFTP UDP source port value. 2619 If tftpsrcp isn't defined, the normal pseudo-random port 2620 number generator is used. 2621 2622 Also, the environment variable tftpdstp is used to supply 2623 the TFTP UDP destination port value. If tftpdstp isn't 2624 defined, the normal port 69 is used. 2625 2626 The purpose for tftpsrcp is to allow a TFTP server to 2627 blindly start the TFTP transfer using the pre-configured 2628 target IP address and UDP port. This has the effect of 2629 "punching through" the (Windows XP) firewall, allowing 2630 the remainder of the TFTP transfer to proceed normally. 2631 A better solution is to properly configure the firewall, 2632 but sometimes that is not allowed. 2633 2634- Hashing support: 2635 CONFIG_CMD_HASH 2636 2637 This enables a generic 'hash' command which can produce 2638 hashes / digests from a few algorithms (e.g. SHA1, SHA256). 2639 2640 CONFIG_HASH_VERIFY 2641 2642 Enable the hash verify command (hash -v). This adds to code 2643 size a little. 2644 2645 CONFIG_SHA1 - support SHA1 hashing 2646 CONFIG_SHA256 - support SHA256 hashing 2647 2648 Note: There is also a sha1sum command, which should perhaps 2649 be deprecated in favour of 'hash sha1'. 2650 2651- Freescale i.MX specific commands: 2652 CONFIG_CMD_HDMIDETECT 2653 This enables 'hdmidet' command which returns true if an 2654 HDMI monitor is detected. This command is i.MX 6 specific. 2655 2656 CONFIG_CMD_BMODE 2657 This enables the 'bmode' (bootmode) command for forcing 2658 a boot from specific media. 2659 2660 This is useful for forcing the ROM's usb downloader to 2661 activate upon a watchdog reset which is nice when iterating 2662 on U-Boot. Using the reset button or running bmode normal 2663 will set it back to normal. This command currently 2664 supports i.MX53 and i.MX6. 2665 2666- Signing support: 2667 CONFIG_RSA 2668 2669 This enables the RSA algorithm used for FIT image verification 2670 in U-Boot. See doc/uImage/signature for more information. 2671 2672 The signing part is build into mkimage regardless of this 2673 option. 2674 2675 2676- Show boot progress: 2677 CONFIG_SHOW_BOOT_PROGRESS 2678 2679 Defining this option allows to add some board- 2680 specific code (calling a user-provided function 2681 "show_boot_progress(int)") that enables you to show 2682 the system's boot progress on some display (for 2683 example, some LED's) on your board. At the moment, 2684 the following checkpoints are implemented: 2685 2686- Detailed boot stage timing 2687 CONFIG_BOOTSTAGE 2688 Define this option to get detailed timing of each stage 2689 of the boot process. 2690 2691 CONFIG_BOOTSTAGE_USER_COUNT 2692 This is the number of available user bootstage records. 2693 Each time you call bootstage_mark(BOOTSTAGE_ID_ALLOC, ...) 2694 a new ID will be allocated from this stash. If you exceed 2695 the limit, recording will stop. 2696 2697 CONFIG_BOOTSTAGE_REPORT 2698 Define this to print a report before boot, similar to this: 2699 2700 Timer summary in microseconds: 2701 Mark Elapsed Stage 2702 0 0 reset 2703 3,575,678 3,575,678 board_init_f start 2704 3,575,695 17 arch_cpu_init A9 2705 3,575,777 82 arch_cpu_init done 2706 3,659,598 83,821 board_init_r start 2707 3,910,375 250,777 main_loop 2708 29,916,167 26,005,792 bootm_start 2709 30,361,327 445,160 start_kernel 2710 2711 CONFIG_CMD_BOOTSTAGE 2712 Add a 'bootstage' command which supports printing a report 2713 and un/stashing of bootstage data. 2714 2715 CONFIG_BOOTSTAGE_FDT 2716 Stash the bootstage information in the FDT. A root 'bootstage' 2717 node is created with each bootstage id as a child. Each child 2718 has a 'name' property and either 'mark' containing the 2719 mark time in microsecond, or 'accum' containing the 2720 accumulated time for that bootstage id in microseconds. 2721 For example: 2722 2723 bootstage { 2724 154 { 2725 name = "board_init_f"; 2726 mark = <3575678>; 2727 }; 2728 170 { 2729 name = "lcd"; 2730 accum = <33482>; 2731 }; 2732 }; 2733 2734 Code in the Linux kernel can find this in /proc/devicetree. 2735 2736Legacy uImage format: 2737 2738 Arg Where When 2739 1 common/cmd_bootm.c before attempting to boot an image 2740 -1 common/cmd_bootm.c Image header has bad magic number 2741 2 common/cmd_bootm.c Image header has correct magic number 2742 -2 common/cmd_bootm.c Image header has bad checksum 2743 3 common/cmd_bootm.c Image header has correct checksum 2744 -3 common/cmd_bootm.c Image data has bad checksum 2745 4 common/cmd_bootm.c Image data has correct checksum 2746 -4 common/cmd_bootm.c Image is for unsupported architecture 2747 5 common/cmd_bootm.c Architecture check OK 2748 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi) 2749 6 common/cmd_bootm.c Image Type check OK 2750 -6 common/cmd_bootm.c gunzip uncompression error 2751 -7 common/cmd_bootm.c Unimplemented compression type 2752 7 common/cmd_bootm.c Uncompression OK 2753 8 common/cmd_bootm.c No uncompress/copy overwrite error 2754 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 2755 2756 9 common/image.c Start initial ramdisk verification 2757 -10 common/image.c Ramdisk header has bad magic number 2758 -11 common/image.c Ramdisk header has bad checksum 2759 10 common/image.c Ramdisk header is OK 2760 -12 common/image.c Ramdisk data has bad checksum 2761 11 common/image.c Ramdisk data has correct checksum 2762 12 common/image.c Ramdisk verification complete, start loading 2763 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk) 2764 13 common/image.c Start multifile image verification 2765 14 common/image.c No initial ramdisk, no multifile, continue. 2766 2767 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS 2768 2769 -30 arch/powerpc/lib/board.c Fatal error, hang the system 2770 -31 post/post.c POST test failed, detected by post_output_backlog() 2771 -32 post/post.c POST test failed, detected by post_run_single() 2772 2773 34 common/cmd_doc.c before loading a Image from a DOC device 2774 -35 common/cmd_doc.c Bad usage of "doc" command 2775 35 common/cmd_doc.c correct usage of "doc" command 2776 -36 common/cmd_doc.c No boot device 2777 36 common/cmd_doc.c correct boot device 2778 -37 common/cmd_doc.c Unknown Chip ID on boot device 2779 37 common/cmd_doc.c correct chip ID found, device available 2780 -38 common/cmd_doc.c Read Error on boot device 2781 38 common/cmd_doc.c reading Image header from DOC device OK 2782 -39 common/cmd_doc.c Image header has bad magic number 2783 39 common/cmd_doc.c Image header has correct magic number 2784 -40 common/cmd_doc.c Error reading Image from DOC device 2785 40 common/cmd_doc.c Image header has correct magic number 2786 41 common/cmd_ide.c before loading a Image from a IDE device 2787 -42 common/cmd_ide.c Bad usage of "ide" command 2788 42 common/cmd_ide.c correct usage of "ide" command 2789 -43 common/cmd_ide.c No boot device 2790 43 common/cmd_ide.c boot device found 2791 -44 common/cmd_ide.c Device not available 2792 44 common/cmd_ide.c Device available 2793 -45 common/cmd_ide.c wrong partition selected 2794 45 common/cmd_ide.c partition selected 2795 -46 common/cmd_ide.c Unknown partition table 2796 46 common/cmd_ide.c valid partition table found 2797 -47 common/cmd_ide.c Invalid partition type 2798 47 common/cmd_ide.c correct partition type 2799 -48 common/cmd_ide.c Error reading Image Header on boot device 2800 48 common/cmd_ide.c reading Image Header from IDE device OK 2801 -49 common/cmd_ide.c Image header has bad magic number 2802 49 common/cmd_ide.c Image header has correct magic number 2803 -50 common/cmd_ide.c Image header has bad checksum 2804 50 common/cmd_ide.c Image header has correct checksum 2805 -51 common/cmd_ide.c Error reading Image from IDE device 2806 51 common/cmd_ide.c reading Image from IDE device OK 2807 52 common/cmd_nand.c before loading a Image from a NAND device 2808 -53 common/cmd_nand.c Bad usage of "nand" command 2809 53 common/cmd_nand.c correct usage of "nand" command 2810 -54 common/cmd_nand.c No boot device 2811 54 common/cmd_nand.c boot device found 2812 -55 common/cmd_nand.c Unknown Chip ID on boot device 2813 55 common/cmd_nand.c correct chip ID found, device available 2814 -56 common/cmd_nand.c Error reading Image Header on boot device 2815 56 common/cmd_nand.c reading Image Header from NAND device OK 2816 -57 common/cmd_nand.c Image header has bad magic number 2817 57 common/cmd_nand.c Image header has correct magic number 2818 -58 common/cmd_nand.c Error reading Image from NAND device 2819 58 common/cmd_nand.c reading Image from NAND device OK 2820 2821 -60 common/env_common.c Environment has a bad CRC, using default 2822 2823 64 net/eth.c starting with Ethernet configuration. 2824 -64 net/eth.c no Ethernet found. 2825 65 net/eth.c Ethernet found. 2826 2827 -80 common/cmd_net.c usage wrong 2828 80 common/cmd_net.c before calling NetLoop() 2829 -81 common/cmd_net.c some error in NetLoop() occurred 2830 81 common/cmd_net.c NetLoop() back without error 2831 -82 common/cmd_net.c size == 0 (File with size 0 loaded) 2832 82 common/cmd_net.c trying automatic boot 2833 83 common/cmd_net.c running "source" command 2834 -83 common/cmd_net.c some error in automatic boot or "source" command 2835 84 common/cmd_net.c end without errors 2836 2837FIT uImage format: 2838 2839 Arg Where When 2840 100 common/cmd_bootm.c Kernel FIT Image has correct format 2841 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format 2842 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration 2843 -101 common/cmd_bootm.c Can't get configuration for kernel subimage 2844 102 common/cmd_bootm.c Kernel unit name specified 2845 -103 common/cmd_bootm.c Can't get kernel subimage node offset 2846 103 common/cmd_bootm.c Found configuration node 2847 104 common/cmd_bootm.c Got kernel subimage node offset 2848 -104 common/cmd_bootm.c Kernel subimage hash verification failed 2849 105 common/cmd_bootm.c Kernel subimage hash verification OK 2850 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture 2851 106 common/cmd_bootm.c Architecture check OK 2852 -106 common/cmd_bootm.c Kernel subimage has wrong type 2853 107 common/cmd_bootm.c Kernel subimage type OK 2854 -107 common/cmd_bootm.c Can't get kernel subimage data/size 2855 108 common/cmd_bootm.c Got kernel subimage data/size 2856 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT) 2857 -109 common/cmd_bootm.c Can't get kernel subimage type 2858 -110 common/cmd_bootm.c Can't get kernel subimage comp 2859 -111 common/cmd_bootm.c Can't get kernel subimage os 2860 -112 common/cmd_bootm.c Can't get kernel subimage load address 2861 -113 common/cmd_bootm.c Image uncompress/copy overwrite error 2862 2863 120 common/image.c Start initial ramdisk verification 2864 -120 common/image.c Ramdisk FIT image has incorrect format 2865 121 common/image.c Ramdisk FIT image has correct format 2866 122 common/image.c No ramdisk subimage unit name, using configuration 2867 -122 common/image.c Can't get configuration for ramdisk subimage 2868 123 common/image.c Ramdisk unit name specified 2869 -124 common/image.c Can't get ramdisk subimage node offset 2870 125 common/image.c Got ramdisk subimage node offset 2871 -125 common/image.c Ramdisk subimage hash verification failed 2872 126 common/image.c Ramdisk subimage hash verification OK 2873 -126 common/image.c Ramdisk subimage for unsupported architecture 2874 127 common/image.c Architecture check OK 2875 -127 common/image.c Can't get ramdisk subimage data/size 2876 128 common/image.c Got ramdisk subimage data/size 2877 129 common/image.c Can't get ramdisk load address 2878 -129 common/image.c Got ramdisk load address 2879 2880 -130 common/cmd_doc.c Incorrect FIT image format 2881 131 common/cmd_doc.c FIT image format OK 2882 2883 -140 common/cmd_ide.c Incorrect FIT image format 2884 141 common/cmd_ide.c FIT image format OK 2885 2886 -150 common/cmd_nand.c Incorrect FIT image format 2887 151 common/cmd_nand.c FIT image format OK 2888 2889- FIT image support: 2890 CONFIG_FIT 2891 Enable support for the FIT uImage format. 2892 2893 CONFIG_FIT_BEST_MATCH 2894 When no configuration is explicitly selected, default to the 2895 one whose fdt's compatibility field best matches that of 2896 U-Boot itself. A match is considered "best" if it matches the 2897 most specific compatibility entry of U-Boot's fdt's root node. 2898 The order of entries in the configuration's fdt is ignored. 2899 2900 CONFIG_FIT_SIGNATURE 2901 This option enables signature verification of FIT uImages, 2902 using a hash signed and verified using RSA. See 2903 doc/uImage.FIT/signature.txt for more details. 2904 2905- Standalone program support: 2906 CONFIG_STANDALONE_LOAD_ADDR 2907 2908 This option defines a board specific value for the 2909 address where standalone program gets loaded, thus 2910 overwriting the architecture dependent default 2911 settings. 2912 2913- Frame Buffer Address: 2914 CONFIG_FB_ADDR 2915 2916 Define CONFIG_FB_ADDR if you want to use specific 2917 address for frame buffer. This is typically the case 2918 when using a graphics controller has separate video 2919 memory. U-Boot will then place the frame buffer at 2920 the given address instead of dynamically reserving it 2921 in system RAM by calling lcd_setmem(), which grabs 2922 the memory for the frame buffer depending on the 2923 configured panel size. 2924 2925 Please see board_init_f function. 2926 2927- Automatic software updates via TFTP server 2928 CONFIG_UPDATE_TFTP 2929 CONFIG_UPDATE_TFTP_CNT_MAX 2930 CONFIG_UPDATE_TFTP_MSEC_MAX 2931 2932 These options enable and control the auto-update feature; 2933 for a more detailed description refer to doc/README.update. 2934 2935- MTD Support (mtdparts command, UBI support) 2936 CONFIG_MTD_DEVICE 2937 2938 Adds the MTD device infrastructure from the Linux kernel. 2939 Needed for mtdparts command support. 2940 2941 CONFIG_MTD_PARTITIONS 2942 2943 Adds the MTD partitioning infrastructure from the Linux 2944 kernel. Needed for UBI support. 2945 2946- UBI support 2947 CONFIG_CMD_UBI 2948 2949 Adds commands for interacting with MTD partitions formatted 2950 with the UBI flash translation layer 2951 2952 Requires also defining CONFIG_RBTREE 2953 2954 CONFIG_UBI_SILENCE_MSG 2955 2956 Make the verbose messages from UBI stop printing. This leaves 2957 warnings and errors enabled. 2958 2959- UBIFS support 2960 CONFIG_CMD_UBIFS 2961 2962 Adds commands for interacting with UBI volumes formatted as 2963 UBIFS. UBIFS is read-only in u-boot. 2964 2965 Requires UBI support as well as CONFIG_LZO 2966 2967 CONFIG_UBIFS_SILENCE_MSG 2968 2969 Make the verbose messages from UBIFS stop printing. This leaves 2970 warnings and errors enabled. 2971 2972- SPL framework 2973 CONFIG_SPL 2974 Enable building of SPL globally. 2975 2976 CONFIG_SPL_LDSCRIPT 2977 LDSCRIPT for linking the SPL binary. 2978 2979 CONFIG_SPL_MAX_FOOTPRINT 2980 Maximum size in memory allocated to the SPL, BSS included. 2981 When defined, the linker checks that the actual memory 2982 used by SPL from _start to __bss_end does not exceed it. 2983 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 2984 must not be both defined at the same time. 2985 2986 CONFIG_SPL_MAX_SIZE 2987 Maximum size of the SPL image (text, data, rodata, and 2988 linker lists sections), BSS excluded. 2989 When defined, the linker checks that the actual size does 2990 not exceed it. 2991 2992 CONFIG_SPL_TEXT_BASE 2993 TEXT_BASE for linking the SPL binary. 2994 2995 CONFIG_SPL_RELOC_TEXT_BASE 2996 Address to relocate to. If unspecified, this is equal to 2997 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done). 2998 2999 CONFIG_SPL_BSS_START_ADDR 3000 Link address for the BSS within the SPL binary. 3001 3002 CONFIG_SPL_BSS_MAX_SIZE 3003 Maximum size in memory allocated to the SPL BSS. 3004 When defined, the linker checks that the actual memory used 3005 by SPL from __bss_start to __bss_end does not exceed it. 3006 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 3007 must not be both defined at the same time. 3008 3009 CONFIG_SPL_STACK 3010 Adress of the start of the stack SPL will use 3011 3012 CONFIG_SPL_RELOC_STACK 3013 Adress of the start of the stack SPL will use after 3014 relocation. If unspecified, this is equal to 3015 CONFIG_SPL_STACK. 3016 3017 CONFIG_SYS_SPL_MALLOC_START 3018 Starting address of the malloc pool used in SPL. 3019 3020 CONFIG_SYS_SPL_MALLOC_SIZE 3021 The size of the malloc pool used in SPL. 3022 3023 CONFIG_SPL_FRAMEWORK 3024 Enable the SPL framework under common/. This framework 3025 supports MMC, NAND and YMODEM loading of U-Boot and NAND 3026 NAND loading of the Linux Kernel. 3027 3028 CONFIG_SPL_DISPLAY_PRINT 3029 For ARM, enable an optional function to print more information 3030 about the running system. 3031 3032 CONFIG_SPL_INIT_MINIMAL 3033 Arch init code should be built for a very small image 3034 3035 CONFIG_SPL_LIBCOMMON_SUPPORT 3036 Support for common/libcommon.o in SPL binary 3037 3038 CONFIG_SPL_LIBDISK_SUPPORT 3039 Support for disk/libdisk.o in SPL binary 3040 3041 CONFIG_SPL_I2C_SUPPORT 3042 Support for drivers/i2c/libi2c.o in SPL binary 3043 3044 CONFIG_SPL_GPIO_SUPPORT 3045 Support for drivers/gpio/libgpio.o in SPL binary 3046 3047 CONFIG_SPL_MMC_SUPPORT 3048 Support for drivers/mmc/libmmc.o in SPL binary 3049 3050 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR, 3051 CONFIG_SYS_U_BOOT_MAX_SIZE_SECTORS, 3052 CONFIG_SYS_MMC_SD_FAT_BOOT_PARTITION 3053 Address, size and partition on the MMC to load U-Boot from 3054 when the MMC is being used in raw mode. 3055 3056 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR 3057 Sector to load kernel uImage from when MMC is being 3058 used in raw mode (for Falcon mode) 3059 3060 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR, 3061 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS 3062 Sector and number of sectors to load kernel argument 3063 parameters from when MMC is being used in raw mode 3064 (for falcon mode) 3065 3066 CONFIG_SPL_FAT_SUPPORT 3067 Support for fs/fat/libfat.o in SPL binary 3068 3069 CONFIG_SPL_FAT_LOAD_PAYLOAD_NAME 3070 Filename to read to load U-Boot when reading from FAT 3071 3072 CONFIG_SPL_FAT_LOAD_KERNEL_NAME 3073 Filename to read to load kernel uImage when reading 3074 from FAT (for Falcon mode) 3075 3076 CONFIG_SPL_FAT_LOAD_ARGS_NAME 3077 Filename to read to load kernel argument parameters 3078 when reading from FAT (for Falcon mode) 3079 3080 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND 3081 Set this for NAND SPL on PPC mpc83xx targets, so that 3082 start.S waits for the rest of the SPL to load before 3083 continuing (the hardware starts execution after just 3084 loading the first page rather than the full 4K). 3085 3086 CONFIG_SPL_NAND_BASE 3087 Include nand_base.c in the SPL. Requires 3088 CONFIG_SPL_NAND_DRIVERS. 3089 3090 CONFIG_SPL_NAND_DRIVERS 3091 SPL uses normal NAND drivers, not minimal drivers. 3092 3093 CONFIG_SPL_NAND_ECC 3094 Include standard software ECC in the SPL 3095 3096 CONFIG_SPL_NAND_SIMPLE 3097 Support for NAND boot using simple NAND drivers that 3098 expose the cmd_ctrl() interface. 3099 3100 CONFIG_SPL_MPC8XXX_INIT_DDR_SUPPORT 3101 Set for the SPL on PPC mpc8xxx targets, support for 3102 arch/powerpc/cpu/mpc8xxx/ddr/libddr.o in SPL binary. 3103 3104 CONFIG_SPL_COMMON_INIT_DDR 3105 Set for common ddr init with serial presence detect in 3106 SPL binary. 3107 3108 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT, 3109 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE, 3110 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS, 3111 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE, 3112 CONFIG_SYS_NAND_ECCBYTES 3113 Defines the size and behavior of the NAND that SPL uses 3114 to read U-Boot 3115 3116 CONFIG_SYS_NAND_U_BOOT_OFFS 3117 Location in NAND to read U-Boot from 3118 3119 CONFIG_SYS_NAND_U_BOOT_DST 3120 Location in memory to load U-Boot to 3121 3122 CONFIG_SYS_NAND_U_BOOT_SIZE 3123 Size of image to load 3124 3125 CONFIG_SYS_NAND_U_BOOT_START 3126 Entry point in loaded image to jump to 3127 3128 CONFIG_SYS_NAND_HW_ECC_OOBFIRST 3129 Define this if you need to first read the OOB and then the 3130 data. This is used for example on davinci plattforms. 3131 3132 CONFIG_SPL_OMAP3_ID_NAND 3133 Support for an OMAP3-specific set of functions to return the 3134 ID and MFR of the first attached NAND chip, if present. 3135 3136 CONFIG_SPL_SERIAL_SUPPORT 3137 Support for drivers/serial/libserial.o in SPL binary 3138 3139 CONFIG_SPL_SPI_FLASH_SUPPORT 3140 Support for drivers/mtd/spi/libspi_flash.o in SPL binary 3141 3142 CONFIG_SPL_SPI_SUPPORT 3143 Support for drivers/spi/libspi.o in SPL binary 3144 3145 CONFIG_SPL_RAM_DEVICE 3146 Support for running image already present in ram, in SPL binary 3147 3148 CONFIG_SPL_LIBGENERIC_SUPPORT 3149 Support for lib/libgeneric.o in SPL binary 3150 3151 CONFIG_SPL_ENV_SUPPORT 3152 Support for the environment operating in SPL binary 3153 3154 CONFIG_SPL_NET_SUPPORT 3155 Support for the net/libnet.o in SPL binary. 3156 It conflicts with SPL env from storage medium specified by 3157 CONFIG_ENV_IS_xxx but CONFIG_ENV_IS_NOWHERE 3158 3159 CONFIG_SPL_PAD_TO 3160 Image offset to which the SPL should be padded before appending 3161 the SPL payload. By default, this is defined as 3162 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 3163 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 3164 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 3165 3166 CONFIG_SPL_TARGET 3167 Final target image containing SPL and payload. Some SPLs 3168 use an arch-specific makefile fragment instead, for 3169 example if more than one image needs to be produced. 3170 3171 CONFIG_FIT_SPL_PRINT 3172 Printing information about a FIT image adds quite a bit of 3173 code to SPL. So this is normally disabled in SPL. Use this 3174 option to re-enable it. This will affect the output of the 3175 bootm command when booting a FIT image. 3176 3177- TPL framework 3178 CONFIG_TPL 3179 Enable building of TPL globally. 3180 3181 CONFIG_TPL_PAD_TO 3182 Image offset to which the TPL should be padded before appending 3183 the TPL payload. By default, this is defined as 3184 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 3185 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 3186 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 3187 3188Modem Support: 3189-------------- 3190 3191[so far only for SMDK2400 boards] 3192 3193- Modem support enable: 3194 CONFIG_MODEM_SUPPORT 3195 3196- RTS/CTS Flow control enable: 3197 CONFIG_HWFLOW 3198 3199- Modem debug support: 3200 CONFIG_MODEM_SUPPORT_DEBUG 3201 3202 Enables debugging stuff (char screen[1024], dbg()) 3203 for modem support. Useful only with BDI2000. 3204 3205- Interrupt support (PPC): 3206 3207 There are common interrupt_init() and timer_interrupt() 3208 for all PPC archs. interrupt_init() calls interrupt_init_cpu() 3209 for CPU specific initialization. interrupt_init_cpu() 3210 should set decrementer_count to appropriate value. If 3211 CPU resets decrementer automatically after interrupt 3212 (ppc4xx) it should set decrementer_count to zero. 3213 timer_interrupt() calls timer_interrupt_cpu() for CPU 3214 specific handling. If board has watchdog / status_led 3215 / other_activity_monitor it works automatically from 3216 general timer_interrupt(). 3217 3218- General: 3219 3220 In the target system modem support is enabled when a 3221 specific key (key combination) is pressed during 3222 power-on. Otherwise U-Boot will boot normally 3223 (autoboot). The key_pressed() function is called from 3224 board_init(). Currently key_pressed() is a dummy 3225 function, returning 1 and thus enabling modem 3226 initialization. 3227 3228 If there are no modem init strings in the 3229 environment, U-Boot proceed to autoboot; the 3230 previous output (banner, info printfs) will be 3231 suppressed, though. 3232 3233 See also: doc/README.Modem 3234 3235Board initialization settings: 3236------------------------------ 3237 3238During Initialization u-boot calls a number of board specific functions 3239to allow the preparation of board specific prerequisites, e.g. pin setup 3240before drivers are initialized. To enable these callbacks the 3241following configuration macros have to be defined. Currently this is 3242architecture specific, so please check arch/your_architecture/lib/board.c 3243typically in board_init_f() and board_init_r(). 3244 3245- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f() 3246- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r() 3247- CONFIG_BOARD_LATE_INIT: Call board_late_init() 3248- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init() 3249 3250Configuration Settings: 3251----------------------- 3252 3253- CONFIG_SYS_LONGHELP: Defined when you want long help messages included; 3254 undefine this when you're short of memory. 3255 3256- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default 3257 width of the commands listed in the 'help' command output. 3258 3259- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to 3260 prompt for user input. 3261 3262- CONFIG_SYS_CBSIZE: Buffer size for input from the Console 3263 3264- CONFIG_SYS_PBSIZE: Buffer size for Console output 3265 3266- CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands 3267 3268- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to 3269 the application (usually a Linux kernel) when it is 3270 booted 3271 3272- CONFIG_SYS_BAUDRATE_TABLE: 3273 List of legal baudrate settings for this board. 3274 3275- CONFIG_SYS_CONSOLE_INFO_QUIET 3276 Suppress display of console information at boot. 3277 3278- CONFIG_SYS_CONSOLE_IS_IN_ENV 3279 If the board specific function 3280 extern int overwrite_console (void); 3281 returns 1, the stdin, stderr and stdout are switched to the 3282 serial port, else the settings in the environment are used. 3283 3284- CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE 3285 Enable the call to overwrite_console(). 3286 3287- CONFIG_SYS_CONSOLE_ENV_OVERWRITE 3288 Enable overwrite of previous console environment settings. 3289 3290- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END: 3291 Begin and End addresses of the area used by the 3292 simple memory test. 3293 3294- CONFIG_SYS_ALT_MEMTEST: 3295 Enable an alternate, more extensive memory test. 3296 3297- CONFIG_SYS_MEMTEST_SCRATCH: 3298 Scratch address used by the alternate memory test 3299 You only need to set this if address zero isn't writeable 3300 3301- CONFIG_SYS_MEM_TOP_HIDE (PPC only): 3302 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header, 3303 this specified memory area will get subtracted from the top 3304 (end) of RAM and won't get "touched" at all by U-Boot. By 3305 fixing up gd->ram_size the Linux kernel should gets passed 3306 the now "corrected" memory size and won't touch it either. 3307 This should work for arch/ppc and arch/powerpc. Only Linux 3308 board ports in arch/powerpc with bootwrapper support that 3309 recalculate the memory size from the SDRAM controller setup 3310 will have to get fixed in Linux additionally. 3311 3312 This option can be used as a workaround for the 440EPx/GRx 3313 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't 3314 be touched. 3315 3316 WARNING: Please make sure that this value is a multiple of 3317 the Linux page size (normally 4k). If this is not the case, 3318 then the end address of the Linux memory will be located at a 3319 non page size aligned address and this could cause major 3320 problems. 3321 3322- CONFIG_SYS_LOADS_BAUD_CHANGE: 3323 Enable temporary baudrate change while serial download 3324 3325- CONFIG_SYS_SDRAM_BASE: 3326 Physical start address of SDRAM. _Must_ be 0 here. 3327 3328- CONFIG_SYS_MBIO_BASE: 3329 Physical start address of Motherboard I/O (if using a 3330 Cogent motherboard) 3331 3332- CONFIG_SYS_FLASH_BASE: 3333 Physical start address of Flash memory. 3334 3335- CONFIG_SYS_MONITOR_BASE: 3336 Physical start address of boot monitor code (set by 3337 make config files to be same as the text base address 3338 (CONFIG_SYS_TEXT_BASE) used when linking) - same as 3339 CONFIG_SYS_FLASH_BASE when booting from flash. 3340 3341- CONFIG_SYS_MONITOR_LEN: 3342 Size of memory reserved for monitor code, used to 3343 determine _at_compile_time_ (!) if the environment is 3344 embedded within the U-Boot image, or in a separate 3345 flash sector. 3346 3347- CONFIG_SYS_MALLOC_LEN: 3348 Size of DRAM reserved for malloc() use. 3349 3350- CONFIG_SYS_BOOTM_LEN: 3351 Normally compressed uImages are limited to an 3352 uncompressed size of 8 MBytes. If this is not enough, 3353 you can define CONFIG_SYS_BOOTM_LEN in your board config file 3354 to adjust this setting to your needs. 3355 3356- CONFIG_SYS_BOOTMAPSZ: 3357 Maximum size of memory mapped by the startup code of 3358 the Linux kernel; all data that must be processed by 3359 the Linux kernel (bd_info, boot arguments, FDT blob if 3360 used) must be put below this limit, unless "bootm_low" 3361 enviroment variable is defined and non-zero. In such case 3362 all data for the Linux kernel must be between "bootm_low" 3363 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment 3364 variable "bootm_mapsize" will override the value of 3365 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined, 3366 then the value in "bootm_size" will be used instead. 3367 3368- CONFIG_SYS_BOOT_RAMDISK_HIGH: 3369 Enable initrd_high functionality. If defined then the 3370 initrd_high feature is enabled and the bootm ramdisk subcommand 3371 is enabled. 3372 3373- CONFIG_SYS_BOOT_GET_CMDLINE: 3374 Enables allocating and saving kernel cmdline in space between 3375 "bootm_low" and "bootm_low" + BOOTMAPSZ. 3376 3377- CONFIG_SYS_BOOT_GET_KBD: 3378 Enables allocating and saving a kernel copy of the bd_info in 3379 space between "bootm_low" and "bootm_low" + BOOTMAPSZ. 3380 3381- CONFIG_SYS_MAX_FLASH_BANKS: 3382 Max number of Flash memory banks 3383 3384- CONFIG_SYS_MAX_FLASH_SECT: 3385 Max number of sectors on a Flash chip 3386 3387- CONFIG_SYS_FLASH_ERASE_TOUT: 3388 Timeout for Flash erase operations (in ms) 3389 3390- CONFIG_SYS_FLASH_WRITE_TOUT: 3391 Timeout for Flash write operations (in ms) 3392 3393- CONFIG_SYS_FLASH_LOCK_TOUT 3394 Timeout for Flash set sector lock bit operation (in ms) 3395 3396- CONFIG_SYS_FLASH_UNLOCK_TOUT 3397 Timeout for Flash clear lock bits operation (in ms) 3398 3399- CONFIG_SYS_FLASH_PROTECTION 3400 If defined, hardware flash sectors protection is used 3401 instead of U-Boot software protection. 3402 3403- CONFIG_SYS_DIRECT_FLASH_TFTP: 3404 3405 Enable TFTP transfers directly to flash memory; 3406 without this option such a download has to be 3407 performed in two steps: (1) download to RAM, and (2) 3408 copy from RAM to flash. 3409 3410 The two-step approach is usually more reliable, since 3411 you can check if the download worked before you erase 3412 the flash, but in some situations (when system RAM is 3413 too limited to allow for a temporary copy of the 3414 downloaded image) this option may be very useful. 3415 3416- CONFIG_SYS_FLASH_CFI: 3417 Define if the flash driver uses extra elements in the 3418 common flash structure for storing flash geometry. 3419 3420- CONFIG_FLASH_CFI_DRIVER 3421 This option also enables the building of the cfi_flash driver 3422 in the drivers directory 3423 3424- CONFIG_FLASH_CFI_MTD 3425 This option enables the building of the cfi_mtd driver 3426 in the drivers directory. The driver exports CFI flash 3427 to the MTD layer. 3428 3429- CONFIG_SYS_FLASH_USE_BUFFER_WRITE 3430 Use buffered writes to flash. 3431 3432- CONFIG_FLASH_SPANSION_S29WS_N 3433 s29ws-n MirrorBit flash has non-standard addresses for buffered 3434 write commands. 3435 3436- CONFIG_SYS_FLASH_QUIET_TEST 3437 If this option is defined, the common CFI flash doesn't 3438 print it's warning upon not recognized FLASH banks. This 3439 is useful, if some of the configured banks are only 3440 optionally available. 3441 3442- CONFIG_FLASH_SHOW_PROGRESS 3443 If defined (must be an integer), print out countdown 3444 digits and dots. Recommended value: 45 (9..1) for 80 3445 column displays, 15 (3..1) for 40 column displays. 3446 3447- CONFIG_FLASH_VERIFY 3448 If defined, the content of the flash (destination) is compared 3449 against the source after the write operation. An error message 3450 will be printed when the contents are not identical. 3451 Please note that this option is useless in nearly all cases, 3452 since such flash programming errors usually are detected earlier 3453 while unprotecting/erasing/programming. Please only enable 3454 this option if you really know what you are doing. 3455 3456- CONFIG_SYS_RX_ETH_BUFFER: 3457 Defines the number of Ethernet receive buffers. On some 3458 Ethernet controllers it is recommended to set this value 3459 to 8 or even higher (EEPRO100 or 405 EMAC), since all 3460 buffers can be full shortly after enabling the interface 3461 on high Ethernet traffic. 3462 Defaults to 4 if not defined. 3463 3464- CONFIG_ENV_MAX_ENTRIES 3465 3466 Maximum number of entries in the hash table that is used 3467 internally to store the environment settings. The default 3468 setting is supposed to be generous and should work in most 3469 cases. This setting can be used to tune behaviour; see 3470 lib/hashtable.c for details. 3471 3472- CONFIG_ENV_FLAGS_LIST_DEFAULT 3473- CONFIG_ENV_FLAGS_LIST_STATIC 3474 Enable validation of the values given to enviroment variables when 3475 calling env set. Variables can be restricted to only decimal, 3476 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined, 3477 the variables can also be restricted to IP address or MAC address. 3478 3479 The format of the list is: 3480 type_attribute = [s|d|x|b|i|m] 3481 access_atribute = [a|r|o|c] 3482 attributes = type_attribute[access_atribute] 3483 entry = variable_name[:attributes] 3484 list = entry[,list] 3485 3486 The type attributes are: 3487 s - String (default) 3488 d - Decimal 3489 x - Hexadecimal 3490 b - Boolean ([1yYtT|0nNfF]) 3491 i - IP address 3492 m - MAC address 3493 3494 The access attributes are: 3495 a - Any (default) 3496 r - Read-only 3497 o - Write-once 3498 c - Change-default 3499 3500 - CONFIG_ENV_FLAGS_LIST_DEFAULT 3501 Define this to a list (string) to define the ".flags" 3502 envirnoment variable in the default or embedded environment. 3503 3504 - CONFIG_ENV_FLAGS_LIST_STATIC 3505 Define this to a list (string) to define validation that 3506 should be done if an entry is not found in the ".flags" 3507 environment variable. To override a setting in the static 3508 list, simply add an entry for the same variable name to the 3509 ".flags" variable. 3510 3511- CONFIG_ENV_ACCESS_IGNORE_FORCE 3512 If defined, don't allow the -f switch to env set override variable 3513 access flags. 3514 3515- CONFIG_SYS_GENERIC_BOARD 3516 This selects the architecture-generic board system instead of the 3517 architecture-specific board files. It is intended to move boards 3518 to this new framework over time. Defining this will disable the 3519 arch/foo/lib/board.c file and use common/board_f.c and 3520 common/board_r.c instead. To use this option your architecture 3521 must support it (i.e. must define __HAVE_ARCH_GENERIC_BOARD in 3522 its config.mk file). If you find problems enabling this option on 3523 your board please report the problem and send patches! 3524 3525- CONFIG_SYS_SYM_OFFSETS 3526 This is set by architectures that use offsets for link symbols 3527 instead of absolute values. So bss_start is obtained using an 3528 offset _bss_start_ofs from CONFIG_SYS_TEXT_BASE, rather than 3529 directly. You should not need to touch this setting. 3530 3531- CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC (OMAP only) 3532 This is set by OMAP boards for the max time that reset should 3533 be asserted. See doc/README.omap-reset-time for details on how 3534 the value can be calulated on a given board. 3535 3536The following definitions that deal with the placement and management 3537of environment data (variable area); in general, we support the 3538following configurations: 3539 3540- CONFIG_BUILD_ENVCRC: 3541 3542 Builds up envcrc with the target environment so that external utils 3543 may easily extract it and embed it in final U-Boot images. 3544 3545- CONFIG_ENV_IS_IN_FLASH: 3546 3547 Define this if the environment is in flash memory. 3548 3549 a) The environment occupies one whole flash sector, which is 3550 "embedded" in the text segment with the U-Boot code. This 3551 happens usually with "bottom boot sector" or "top boot 3552 sector" type flash chips, which have several smaller 3553 sectors at the start or the end. For instance, such a 3554 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In 3555 such a case you would place the environment in one of the 3556 4 kB sectors - with U-Boot code before and after it. With 3557 "top boot sector" type flash chips, you would put the 3558 environment in one of the last sectors, leaving a gap 3559 between U-Boot and the environment. 3560 3561 - CONFIG_ENV_OFFSET: 3562 3563 Offset of environment data (variable area) to the 3564 beginning of flash memory; for instance, with bottom boot 3565 type flash chips the second sector can be used: the offset 3566 for this sector is given here. 3567 3568 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE. 3569 3570 - CONFIG_ENV_ADDR: 3571 3572 This is just another way to specify the start address of 3573 the flash sector containing the environment (instead of 3574 CONFIG_ENV_OFFSET). 3575 3576 - CONFIG_ENV_SECT_SIZE: 3577 3578 Size of the sector containing the environment. 3579 3580 3581 b) Sometimes flash chips have few, equal sized, BIG sectors. 3582 In such a case you don't want to spend a whole sector for 3583 the environment. 3584 3585 - CONFIG_ENV_SIZE: 3586 3587 If you use this in combination with CONFIG_ENV_IS_IN_FLASH 3588 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part 3589 of this flash sector for the environment. This saves 3590 memory for the RAM copy of the environment. 3591 3592 It may also save flash memory if you decide to use this 3593 when your environment is "embedded" within U-Boot code, 3594 since then the remainder of the flash sector could be used 3595 for U-Boot code. It should be pointed out that this is 3596 STRONGLY DISCOURAGED from a robustness point of view: 3597 updating the environment in flash makes it always 3598 necessary to erase the WHOLE sector. If something goes 3599 wrong before the contents has been restored from a copy in 3600 RAM, your target system will be dead. 3601 3602 - CONFIG_ENV_ADDR_REDUND 3603 CONFIG_ENV_SIZE_REDUND 3604 3605 These settings describe a second storage area used to hold 3606 a redundant copy of the environment data, so that there is 3607 a valid backup copy in case there is a power failure during 3608 a "saveenv" operation. 3609 3610BE CAREFUL! Any changes to the flash layout, and some changes to the 3611source code will make it necessary to adapt <board>/u-boot.lds* 3612accordingly! 3613 3614 3615- CONFIG_ENV_IS_IN_NVRAM: 3616 3617 Define this if you have some non-volatile memory device 3618 (NVRAM, battery buffered SRAM) which you want to use for the 3619 environment. 3620 3621 - CONFIG_ENV_ADDR: 3622 - CONFIG_ENV_SIZE: 3623 3624 These two #defines are used to determine the memory area you 3625 want to use for environment. It is assumed that this memory 3626 can just be read and written to, without any special 3627 provision. 3628 3629BE CAREFUL! The first access to the environment happens quite early 3630in U-Boot initalization (when we try to get the setting of for the 3631console baudrate). You *MUST* have mapped your NVRAM area then, or 3632U-Boot will hang. 3633 3634Please note that even with NVRAM we still use a copy of the 3635environment in RAM: we could work on NVRAM directly, but we want to 3636keep settings there always unmodified except somebody uses "saveenv" 3637to save the current settings. 3638 3639 3640- CONFIG_ENV_IS_IN_EEPROM: 3641 3642 Use this if you have an EEPROM or similar serial access 3643 device and a driver for it. 3644 3645 - CONFIG_ENV_OFFSET: 3646 - CONFIG_ENV_SIZE: 3647 3648 These two #defines specify the offset and size of the 3649 environment area within the total memory of your EEPROM. 3650 3651 - CONFIG_SYS_I2C_EEPROM_ADDR: 3652 If defined, specified the chip address of the EEPROM device. 3653 The default address is zero. 3654 3655 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS: 3656 If defined, the number of bits used to address bytes in a 3657 single page in the EEPROM device. A 64 byte page, for example 3658 would require six bits. 3659 3660 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS: 3661 If defined, the number of milliseconds to delay between 3662 page writes. The default is zero milliseconds. 3663 3664 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN: 3665 The length in bytes of the EEPROM memory array address. Note 3666 that this is NOT the chip address length! 3667 3668 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW: 3669 EEPROM chips that implement "address overflow" are ones 3670 like Catalyst 24WC04/08/16 which has 9/10/11 bits of 3671 address and the extra bits end up in the "chip address" bit 3672 slots. This makes a 24WC08 (1Kbyte) chip look like four 256 3673 byte chips. 3674 3675 Note that we consider the length of the address field to 3676 still be one byte because the extra address bits are hidden 3677 in the chip address. 3678 3679 - CONFIG_SYS_EEPROM_SIZE: 3680 The size in bytes of the EEPROM device. 3681 3682 - CONFIG_ENV_EEPROM_IS_ON_I2C 3683 define this, if you have I2C and SPI activated, and your 3684 EEPROM, which holds the environment, is on the I2C bus. 3685 3686 - CONFIG_I2C_ENV_EEPROM_BUS 3687 if you have an Environment on an EEPROM reached over 3688 I2C muxes, you can define here, how to reach this 3689 EEPROM. For example: 3690 3691 #define CONFIG_I2C_ENV_EEPROM_BUS 1 3692 3693 EEPROM which holds the environment, is reached over 3694 a pca9547 i2c mux with address 0x70, channel 3. 3695 3696- CONFIG_ENV_IS_IN_DATAFLASH: 3697 3698 Define this if you have a DataFlash memory device which you 3699 want to use for the environment. 3700 3701 - CONFIG_ENV_OFFSET: 3702 - CONFIG_ENV_ADDR: 3703 - CONFIG_ENV_SIZE: 3704 3705 These three #defines specify the offset and size of the 3706 environment area within the total memory of your DataFlash placed 3707 at the specified address. 3708 3709- CONFIG_ENV_IS_IN_REMOTE: 3710 3711 Define this if you have a remote memory space which you 3712 want to use for the local device's environment. 3713 3714 - CONFIG_ENV_ADDR: 3715 - CONFIG_ENV_SIZE: 3716 3717 These two #defines specify the address and size of the 3718 environment area within the remote memory space. The 3719 local device can get the environment from remote memory 3720 space by SRIO or PCIE links. 3721 3722BE CAREFUL! For some special cases, the local device can not use 3723"saveenv" command. For example, the local device will get the 3724environment stored in a remote NOR flash by SRIO or PCIE link, 3725but it can not erase, write this NOR flash by SRIO or PCIE interface. 3726 3727- CONFIG_ENV_IS_IN_NAND: 3728 3729 Define this if you have a NAND device which you want to use 3730 for the environment. 3731 3732 - CONFIG_ENV_OFFSET: 3733 - CONFIG_ENV_SIZE: 3734 3735 These two #defines specify the offset and size of the environment 3736 area within the first NAND device. CONFIG_ENV_OFFSET must be 3737 aligned to an erase block boundary. 3738 3739 - CONFIG_ENV_OFFSET_REDUND (optional): 3740 3741 This setting describes a second storage area of CONFIG_ENV_SIZE 3742 size used to hold a redundant copy of the environment data, so 3743 that there is a valid backup copy in case there is a power failure 3744 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be 3745 aligned to an erase block boundary. 3746 3747 - CONFIG_ENV_RANGE (optional): 3748 3749 Specifies the length of the region in which the environment 3750 can be written. This should be a multiple of the NAND device's 3751 block size. Specifying a range with more erase blocks than 3752 are needed to hold CONFIG_ENV_SIZE allows bad blocks within 3753 the range to be avoided. 3754 3755 - CONFIG_ENV_OFFSET_OOB (optional): 3756 3757 Enables support for dynamically retrieving the offset of the 3758 environment from block zero's out-of-band data. The 3759 "nand env.oob" command can be used to record this offset. 3760 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when 3761 using CONFIG_ENV_OFFSET_OOB. 3762 3763- CONFIG_NAND_ENV_DST 3764 3765 Defines address in RAM to which the nand_spl code should copy the 3766 environment. If redundant environment is used, it will be copied to 3767 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE. 3768 3769- CONFIG_ENV_IS_IN_UBI: 3770 3771 Define this if you have an UBI volume that you want to use for the 3772 environment. This has the benefit of wear-leveling the environment 3773 accesses, which is important on NAND. 3774 3775 - CONFIG_ENV_UBI_PART: 3776 3777 Define this to a string that is the mtd partition containing the UBI. 3778 3779 - CONFIG_ENV_UBI_VOLUME: 3780 3781 Define this to the name of the volume that you want to store the 3782 environment in. 3783 3784 - CONFIG_ENV_UBI_VOLUME_REDUND: 3785 3786 Define this to the name of another volume to store a second copy of 3787 the environment in. This will enable redundant environments in UBI. 3788 It is assumed that both volumes are in the same MTD partition. 3789 3790 - CONFIG_UBI_SILENCE_MSG 3791 - CONFIG_UBIFS_SILENCE_MSG 3792 3793 You will probably want to define these to avoid a really noisy system 3794 when storing the env in UBI. 3795 3796- CONFIG_ENV_IS_IN_MMC: 3797 3798 Define this if you have an MMC device which you want to use for the 3799 environment. 3800 3801 - CONFIG_SYS_MMC_ENV_DEV: 3802 3803 Specifies which MMC device the environment is stored in. 3804 3805 - CONFIG_SYS_MMC_ENV_PART (optional): 3806 3807 Specifies which MMC partition the environment is stored in. If not 3808 set, defaults to partition 0, the user area. Common values might be 3809 1 (first MMC boot partition), 2 (second MMC boot partition). 3810 3811 - CONFIG_ENV_OFFSET: 3812 - CONFIG_ENV_SIZE: 3813 3814 These two #defines specify the offset and size of the environment 3815 area within the specified MMC device. 3816 3817 If offset is positive (the usual case), it is treated as relative to 3818 the start of the MMC partition. If offset is negative, it is treated 3819 as relative to the end of the MMC partition. This can be useful if 3820 your board may be fitted with different MMC devices, which have 3821 different sizes for the MMC partitions, and you always want the 3822 environment placed at the very end of the partition, to leave the 3823 maximum possible space before it, to store other data. 3824 3825 These two values are in units of bytes, but must be aligned to an 3826 MMC sector boundary. 3827 3828 - CONFIG_ENV_OFFSET_REDUND (optional): 3829 3830 Specifies a second storage area, of CONFIG_ENV_SIZE size, used to 3831 hold a redundant copy of the environment data. This provides a 3832 valid backup copy in case the other copy is corrupted, e.g. due 3833 to a power failure during a "saveenv" operation. 3834 3835 This value may also be positive or negative; this is handled in the 3836 same way as CONFIG_ENV_OFFSET. 3837 3838 This value is also in units of bytes, but must also be aligned to 3839 an MMC sector boundary. 3840 3841 - CONFIG_ENV_SIZE_REDUND (optional): 3842 3843 This value need not be set, even when CONFIG_ENV_OFFSET_REDUND is 3844 set. If this value is set, it must be set to the same value as 3845 CONFIG_ENV_SIZE. 3846 3847- CONFIG_SYS_SPI_INIT_OFFSET 3848 3849 Defines offset to the initial SPI buffer area in DPRAM. The 3850 area is used at an early stage (ROM part) if the environment 3851 is configured to reside in the SPI EEPROM: We need a 520 byte 3852 scratch DPRAM area. It is used between the two initialization 3853 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems 3854 to be a good choice since it makes it far enough from the 3855 start of the data area as well as from the stack pointer. 3856 3857Please note that the environment is read-only until the monitor 3858has been relocated to RAM and a RAM copy of the environment has been 3859created; also, when using EEPROM you will have to use getenv_f() 3860until then to read environment variables. 3861 3862The environment is protected by a CRC32 checksum. Before the monitor 3863is relocated into RAM, as a result of a bad CRC you will be working 3864with the compiled-in default environment - *silently*!!! [This is 3865necessary, because the first environment variable we need is the 3866"baudrate" setting for the console - if we have a bad CRC, we don't 3867have any device yet where we could complain.] 3868 3869Note: once the monitor has been relocated, then it will complain if 3870the default environment is used; a new CRC is computed as soon as you 3871use the "saveenv" command to store a valid environment. 3872 3873- CONFIG_SYS_FAULT_ECHO_LINK_DOWN: 3874 Echo the inverted Ethernet link state to the fault LED. 3875 3876 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR 3877 also needs to be defined. 3878 3879- CONFIG_SYS_FAULT_MII_ADDR: 3880 MII address of the PHY to check for the Ethernet link state. 3881 3882- CONFIG_NS16550_MIN_FUNCTIONS: 3883 Define this if you desire to only have use of the NS16550_init 3884 and NS16550_putc functions for the serial driver located at 3885 drivers/serial/ns16550.c. This option is useful for saving 3886 space for already greatly restricted images, including but not 3887 limited to NAND_SPL configurations. 3888 3889- CONFIG_DISPLAY_BOARDINFO 3890 Display information about the board that U-Boot is running on 3891 when U-Boot starts up. The board function checkboard() is called 3892 to do this. 3893 3894- CONFIG_DISPLAY_BOARDINFO_LATE 3895 Similar to the previous option, but display this information 3896 later, once stdio is running and output goes to the LCD, if 3897 present. 3898 3899Low Level (hardware related) configuration options: 3900--------------------------------------------------- 3901 3902- CONFIG_SYS_CACHELINE_SIZE: 3903 Cache Line Size of the CPU. 3904 3905- CONFIG_SYS_DEFAULT_IMMR: 3906 Default address of the IMMR after system reset. 3907 3908 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU, 3909 and RPXsuper) to be able to adjust the position of 3910 the IMMR register after a reset. 3911 3912- CONFIG_SYS_CCSRBAR_DEFAULT: 3913 Default (power-on reset) physical address of CCSR on Freescale 3914 PowerPC SOCs. 3915 3916- CONFIG_SYS_CCSRBAR: 3917 Virtual address of CCSR. On a 32-bit build, this is typically 3918 the same value as CONFIG_SYS_CCSRBAR_DEFAULT. 3919 3920 CONFIG_SYS_DEFAULT_IMMR must also be set to this value, 3921 for cross-platform code that uses that macro instead. 3922 3923- CONFIG_SYS_CCSRBAR_PHYS: 3924 Physical address of CCSR. CCSR can be relocated to a new 3925 physical address, if desired. In this case, this macro should 3926 be set to that address. Otherwise, it should be set to the 3927 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR 3928 is typically relocated on 36-bit builds. It is recommended 3929 that this macro be defined via the _HIGH and _LOW macros: 3930 3931 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH 3932 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW) 3933 3934- CONFIG_SYS_CCSRBAR_PHYS_HIGH: 3935 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically 3936 either 0 (32-bit build) or 0xF (36-bit build). This macro is 3937 used in assembly code, so it must not contain typecasts or 3938 integer size suffixes (e.g. "ULL"). 3939 3940- CONFIG_SYS_CCSRBAR_PHYS_LOW: 3941 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is 3942 used in assembly code, so it must not contain typecasts or 3943 integer size suffixes (e.g. "ULL"). 3944 3945- CONFIG_SYS_CCSR_DO_NOT_RELOCATE: 3946 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be 3947 forced to a value that ensures that CCSR is not relocated. 3948 3949- Floppy Disk Support: 3950 CONFIG_SYS_FDC_DRIVE_NUMBER 3951 3952 the default drive number (default value 0) 3953 3954 CONFIG_SYS_ISA_IO_STRIDE 3955 3956 defines the spacing between FDC chipset registers 3957 (default value 1) 3958 3959 CONFIG_SYS_ISA_IO_OFFSET 3960 3961 defines the offset of register from address. It 3962 depends on which part of the data bus is connected to 3963 the FDC chipset. (default value 0) 3964 3965 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and 3966 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their 3967 default value. 3968 3969 if CONFIG_SYS_FDC_HW_INIT is defined, then the function 3970 fdc_hw_init() is called at the beginning of the FDC 3971 setup. fdc_hw_init() must be provided by the board 3972 source code. It is used to make hardware dependant 3973 initializations. 3974 3975- CONFIG_IDE_AHB: 3976 Most IDE controllers were designed to be connected with PCI 3977 interface. Only few of them were designed for AHB interface. 3978 When software is doing ATA command and data transfer to 3979 IDE devices through IDE-AHB controller, some additional 3980 registers accessing to these kind of IDE-AHB controller 3981 is requierd. 3982 3983- CONFIG_SYS_IMMR: Physical address of the Internal Memory. 3984 DO NOT CHANGE unless you know exactly what you're 3985 doing! (11-4) [MPC8xx/82xx systems only] 3986 3987- CONFIG_SYS_INIT_RAM_ADDR: 3988 3989 Start address of memory area that can be used for 3990 initial data and stack; please note that this must be 3991 writable memory that is working WITHOUT special 3992 initialization, i. e. you CANNOT use normal RAM which 3993 will become available only after programming the 3994 memory controller and running certain initialization 3995 sequences. 3996 3997 U-Boot uses the following memory types: 3998 - MPC8xx and MPC8260: IMMR (internal memory of the CPU) 3999 - MPC824X: data cache 4000 - PPC4xx: data cache 4001 4002- CONFIG_SYS_GBL_DATA_OFFSET: 4003 4004 Offset of the initial data structure in the memory 4005 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually 4006 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial 4007 data is located at the end of the available space 4008 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE - 4009 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just 4010 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR + 4011 CONFIG_SYS_GBL_DATA_OFFSET) downward. 4012 4013 Note: 4014 On the MPC824X (or other systems that use the data 4015 cache for initial memory) the address chosen for 4016 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must 4017 point to an otherwise UNUSED address space between 4018 the top of RAM and the start of the PCI space. 4019 4020- CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6) 4021 4022- CONFIG_SYS_SYPCR: System Protection Control (11-9) 4023 4024- CONFIG_SYS_TBSCR: Time Base Status and Control (11-26) 4025 4026- CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31) 4027 4028- CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30) 4029 4030- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27) 4031 4032- CONFIG_SYS_OR_TIMING_SDRAM: 4033 SDRAM timing 4034 4035- CONFIG_SYS_MAMR_PTA: 4036 periodic timer for refresh 4037 4038- CONFIG_SYS_DER: Debug Event Register (37-47) 4039 4040- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM, 4041 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP, 4042 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM, 4043 CONFIG_SYS_BR1_PRELIM: 4044 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 4045 4046- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 4047 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM, 4048 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM: 4049 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 4050 4051- CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K, 4052 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL: 4053 Machine Mode Register and Memory Periodic Timer 4054 Prescaler definitions (SDRAM timing) 4055 4056- CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]: 4057 enable I2C microcode relocation patch (MPC8xx); 4058 define relocation offset in DPRAM [DSP2] 4059 4060- CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]: 4061 enable SMC microcode relocation patch (MPC8xx); 4062 define relocation offset in DPRAM [SMC1] 4063 4064- CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]: 4065 enable SPI microcode relocation patch (MPC8xx); 4066 define relocation offset in DPRAM [SCC4] 4067 4068- CONFIG_SYS_USE_OSCCLK: 4069 Use OSCM clock mode on MBX8xx board. Be careful, 4070 wrong setting might damage your board. Read 4071 doc/README.MBX before setting this variable! 4072 4073- CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only) 4074 Offset of the bootmode word in DPRAM used by post 4075 (Power On Self Tests). This definition overrides 4076 #define'd default value in commproc.h resp. 4077 cpm_8260.h. 4078 4079- CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB, 4080 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL, 4081 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS, 4082 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB, 4083 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START, 4084 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL, 4085 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE, 4086 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only) 4087 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set. 4088 4089- CONFIG_PCI_DISABLE_PCIE: 4090 Disable PCI-Express on systems where it is supported but not 4091 required. 4092 4093- CONFIG_PCI_ENUM_ONLY 4094 Only scan through and get the devices on the busses. 4095 Don't do any setup work, presumably because someone or 4096 something has already done it, and we don't need to do it 4097 a second time. Useful for platforms that are pre-booted 4098 by coreboot or similar. 4099 4100- CONFIG_PCI_INDIRECT_BRIDGE: 4101 Enable support for indirect PCI bridges. 4102 4103- CONFIG_SYS_SRIO: 4104 Chip has SRIO or not 4105 4106- CONFIG_SRIO1: 4107 Board has SRIO 1 port available 4108 4109- CONFIG_SRIO2: 4110 Board has SRIO 2 port available 4111 4112- CONFIG_SRIO_PCIE_BOOT_MASTER 4113 Board can support master function for Boot from SRIO and PCIE 4114 4115- CONFIG_SYS_SRIOn_MEM_VIRT: 4116 Virtual Address of SRIO port 'n' memory region 4117 4118- CONFIG_SYS_SRIOn_MEM_PHYS: 4119 Physical Address of SRIO port 'n' memory region 4120 4121- CONFIG_SYS_SRIOn_MEM_SIZE: 4122 Size of SRIO port 'n' memory region 4123 4124- CONFIG_SYS_NAND_BUSWIDTH_16BIT 4125 Defined to tell the NAND controller that the NAND chip is using 4126 a 16 bit bus. 4127 Not all NAND drivers use this symbol. 4128 Example of drivers that use it: 4129 - drivers/mtd/nand/ndfc.c 4130 - drivers/mtd/nand/mxc_nand.c 4131 4132- CONFIG_SYS_NDFC_EBC0_CFG 4133 Sets the EBC0_CFG register for the NDFC. If not defined 4134 a default value will be used. 4135 4136- CONFIG_SPD_EEPROM 4137 Get DDR timing information from an I2C EEPROM. Common 4138 with pluggable memory modules such as SODIMMs 4139 4140 SPD_EEPROM_ADDRESS 4141 I2C address of the SPD EEPROM 4142 4143- CONFIG_SYS_SPD_BUS_NUM 4144 If SPD EEPROM is on an I2C bus other than the first 4145 one, specify here. Note that the value must resolve 4146 to something your driver can deal with. 4147 4148- CONFIG_SYS_DDR_RAW_TIMING 4149 Get DDR timing information from other than SPD. Common with 4150 soldered DDR chips onboard without SPD. DDR raw timing 4151 parameters are extracted from datasheet and hard-coded into 4152 header files or board specific files. 4153 4154- CONFIG_FSL_DDR_INTERACTIVE 4155 Enable interactive DDR debugging. See doc/README.fsl-ddr. 4156 4157- CONFIG_SYS_83XX_DDR_USES_CS0 4158 Only for 83xx systems. If specified, then DDR should 4159 be configured using CS0 and CS1 instead of CS2 and CS3. 4160 4161- CONFIG_ETHER_ON_FEC[12] 4162 Define to enable FEC[12] on a 8xx series processor. 4163 4164- CONFIG_FEC[12]_PHY 4165 Define to the hardcoded PHY address which corresponds 4166 to the given FEC; i. e. 4167 #define CONFIG_FEC1_PHY 4 4168 means that the PHY with address 4 is connected to FEC1 4169 4170 When set to -1, means to probe for first available. 4171 4172- CONFIG_FEC[12]_PHY_NORXERR 4173 The PHY does not have a RXERR line (RMII only). 4174 (so program the FEC to ignore it). 4175 4176- CONFIG_RMII 4177 Enable RMII mode for all FECs. 4178 Note that this is a global option, we can't 4179 have one FEC in standard MII mode and another in RMII mode. 4180 4181- CONFIG_CRC32_VERIFY 4182 Add a verify option to the crc32 command. 4183 The syntax is: 4184 4185 => crc32 -v <address> <count> <crc32> 4186 4187 Where address/count indicate a memory area 4188 and crc32 is the correct crc32 which the 4189 area should have. 4190 4191- CONFIG_LOOPW 4192 Add the "loopw" memory command. This only takes effect if 4193 the memory commands are activated globally (CONFIG_CMD_MEM). 4194 4195- CONFIG_MX_CYCLIC 4196 Add the "mdc" and "mwc" memory commands. These are cyclic 4197 "md/mw" commands. 4198 Examples: 4199 4200 => mdc.b 10 4 500 4201 This command will print 4 bytes (10,11,12,13) each 500 ms. 4202 4203 => mwc.l 100 12345678 10 4204 This command will write 12345678 to address 100 all 10 ms. 4205 4206 This only takes effect if the memory commands are activated 4207 globally (CONFIG_CMD_MEM). 4208 4209- CONFIG_SKIP_LOWLEVEL_INIT 4210 [ARM, NDS32, MIPS only] If this variable is defined, then certain 4211 low level initializations (like setting up the memory 4212 controller) are omitted and/or U-Boot does not 4213 relocate itself into RAM. 4214 4215 Normally this variable MUST NOT be defined. The only 4216 exception is when U-Boot is loaded (to RAM) by some 4217 other boot loader or by a debugger which performs 4218 these initializations itself. 4219 4220- CONFIG_SPL_BUILD 4221 Modifies the behaviour of start.S when compiling a loader 4222 that is executed before the actual U-Boot. E.g. when 4223 compiling a NAND SPL. 4224 4225- CONFIG_TPL_BUILD 4226 Modifies the behaviour of start.S when compiling a loader 4227 that is executed after the SPL and before the actual U-Boot. 4228 It is loaded by the SPL. 4229 4230- CONFIG_SYS_MPC85XX_NO_RESETVEC 4231 Only for 85xx systems. If this variable is specified, the section 4232 .resetvec is not kept and the section .bootpg is placed in the 4233 previous 4k of the .text section. 4234 4235- CONFIG_ARCH_MAP_SYSMEM 4236 Generally U-Boot (and in particular the md command) uses 4237 effective address. It is therefore not necessary to regard 4238 U-Boot address as virtual addresses that need to be translated 4239 to physical addresses. However, sandbox requires this, since 4240 it maintains its own little RAM buffer which contains all 4241 addressable memory. This option causes some memory accesses 4242 to be mapped through map_sysmem() / unmap_sysmem(). 4243 4244- CONFIG_USE_ARCH_MEMCPY 4245 CONFIG_USE_ARCH_MEMSET 4246 If these options are used a optimized version of memcpy/memset will 4247 be used if available. These functions may be faster under some 4248 conditions but may increase the binary size. 4249 4250- CONFIG_X86_RESET_VECTOR 4251 If defined, the x86 reset vector code is included. This is not 4252 needed when U-Boot is running from Coreboot. 4253 4254- CONFIG_SYS_MPUCLK 4255 Defines the MPU clock speed (in MHz). 4256 4257 NOTE : currently only supported on AM335x platforms. 4258 4259Freescale QE/FMAN Firmware Support: 4260----------------------------------- 4261 4262The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the 4263loading of "firmware", which is encoded in the QE firmware binary format. 4264This firmware often needs to be loaded during U-Boot booting, so macros 4265are used to identify the storage device (NOR flash, SPI, etc) and the address 4266within that device. 4267 4268- CONFIG_SYS_QE_FMAN_FW_ADDR 4269 The address in the storage device where the firmware is located. The 4270 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 4271 is also specified. 4272 4273- CONFIG_SYS_QE_FMAN_FW_LENGTH 4274 The maximum possible size of the firmware. The firmware binary format 4275 has a field that specifies the actual size of the firmware, but it 4276 might not be possible to read any part of the firmware unless some 4277 local storage is allocated to hold the entire firmware first. 4278 4279- CONFIG_SYS_QE_FMAN_FW_IN_NOR 4280 Specifies that QE/FMAN firmware is located in NOR flash, mapped as 4281 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the 4282 virtual address in NOR flash. 4283 4284- CONFIG_SYS_QE_FMAN_FW_IN_NAND 4285 Specifies that QE/FMAN firmware is located in NAND flash. 4286 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash. 4287 4288- CONFIG_SYS_QE_FMAN_FW_IN_MMC 4289 Specifies that QE/FMAN firmware is located on the primary SD/MMC 4290 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 4291 4292- CONFIG_SYS_QE_FMAN_FW_IN_SPIFLASH 4293 Specifies that QE/FMAN firmware is located on the primary SPI 4294 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 4295 4296- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE 4297 Specifies that QE/FMAN firmware is located in the remote (master) 4298 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which 4299 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound 4300 window->master inbound window->master LAW->the ucode address in 4301 master's memory space. 4302 4303Building the Software: 4304====================== 4305 4306Building U-Boot has been tested in several native build environments 4307and in many different cross environments. Of course we cannot support 4308all possibly existing versions of cross development tools in all 4309(potentially obsolete) versions. In case of tool chain problems we 4310recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK) 4311which is extensively used to build and test U-Boot. 4312 4313If you are not using a native environment, it is assumed that you 4314have GNU cross compiling tools available in your path. In this case, 4315you must set the environment variable CROSS_COMPILE in your shell. 4316Note that no changes to the Makefile or any other source files are 4317necessary. For example using the ELDK on a 4xx CPU, please enter: 4318 4319 $ CROSS_COMPILE=ppc_4xx- 4320 $ export CROSS_COMPILE 4321 4322Note: If you wish to generate Windows versions of the utilities in 4323 the tools directory you can use the MinGW toolchain 4324 (http://www.mingw.org). Set your HOST tools to the MinGW 4325 toolchain and execute 'make tools'. For example: 4326 4327 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools 4328 4329 Binaries such as tools/mkimage.exe will be created which can 4330 be executed on computers running Windows. 4331 4332U-Boot is intended to be simple to build. After installing the 4333sources you must configure U-Boot for one specific board type. This 4334is done by typing: 4335 4336 make NAME_config 4337 4338where "NAME_config" is the name of one of the existing configu- 4339rations; see boards.cfg for supported names. 4340 4341Note: for some board special configuration names may exist; check if 4342 additional information is available from the board vendor; for 4343 instance, the TQM823L systems are available without (standard) 4344 or with LCD support. You can select such additional "features" 4345 when choosing the configuration, i. e. 4346 4347 make TQM823L_config 4348 - will configure for a plain TQM823L, i. e. no LCD support 4349 4350 make TQM823L_LCD_config 4351 - will configure for a TQM823L with U-Boot console on LCD 4352 4353 etc. 4354 4355 4356Finally, type "make all", and you should get some working U-Boot 4357images ready for download to / installation on your system: 4358 4359- "u-boot.bin" is a raw binary image 4360- "u-boot" is an image in ELF binary format 4361- "u-boot.srec" is in Motorola S-Record format 4362 4363By default the build is performed locally and the objects are saved 4364in the source directory. One of the two methods can be used to change 4365this behavior and build U-Boot to some external directory: 4366 43671. Add O= to the make command line invocations: 4368 4369 make O=/tmp/build distclean 4370 make O=/tmp/build NAME_config 4371 make O=/tmp/build all 4372 43732. Set environment variable BUILD_DIR to point to the desired location: 4374 4375 export BUILD_DIR=/tmp/build 4376 make distclean 4377 make NAME_config 4378 make all 4379 4380Note that the command line "O=" setting overrides the BUILD_DIR environment 4381variable. 4382 4383 4384Please be aware that the Makefiles assume you are using GNU make, so 4385for instance on NetBSD you might need to use "gmake" instead of 4386native "make". 4387 4388 4389If the system board that you have is not listed, then you will need 4390to port U-Boot to your hardware platform. To do this, follow these 4391steps: 4392 43931. Add a new configuration option for your board to the toplevel 4394 "boards.cfg" file, using the existing entries as examples. 4395 Follow the instructions there to keep the boards in order. 43962. Create a new directory to hold your board specific code. Add any 4397 files you need. In your board directory, you will need at least 4398 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds". 43993. Create a new configuration file "include/configs/<board>.h" for 4400 your board 44013. If you're porting U-Boot to a new CPU, then also create a new 4402 directory to hold your CPU specific code. Add any files you need. 44034. Run "make <board>_config" with your new name. 44045. Type "make", and you should get a working "u-boot.srec" file 4405 to be installed on your target system. 44066. Debug and solve any problems that might arise. 4407 [Of course, this last step is much harder than it sounds.] 4408 4409 4410Testing of U-Boot Modifications, Ports to New Hardware, etc.: 4411============================================================== 4412 4413If you have modified U-Boot sources (for instance added a new board 4414or support for new devices, a new CPU, etc.) you are expected to 4415provide feedback to the other developers. The feedback normally takes 4416the form of a "patch", i. e. a context diff against a certain (latest 4417official or latest in the git repository) version of U-Boot sources. 4418 4419But before you submit such a patch, please verify that your modifi- 4420cation did not break existing code. At least make sure that *ALL* of 4421the supported boards compile WITHOUT ANY compiler warnings. To do so, 4422just run the "MAKEALL" script, which will configure and build U-Boot 4423for ALL supported system. Be warned, this will take a while. You can 4424select which (cross) compiler to use by passing a `CROSS_COMPILE' 4425environment variable to the script, i. e. to use the ELDK cross tools 4426you can type 4427 4428 CROSS_COMPILE=ppc_8xx- MAKEALL 4429 4430or to build on a native PowerPC system you can type 4431 4432 CROSS_COMPILE=' ' MAKEALL 4433 4434When using the MAKEALL script, the default behaviour is to build 4435U-Boot in the source directory. This location can be changed by 4436setting the BUILD_DIR environment variable. Also, for each target 4437built, the MAKEALL script saves two log files (<target>.ERR and 4438<target>.MAKEALL) in the <source dir>/LOG directory. This default 4439location can be changed by setting the MAKEALL_LOGDIR environment 4440variable. For example: 4441 4442 export BUILD_DIR=/tmp/build 4443 export MAKEALL_LOGDIR=/tmp/log 4444 CROSS_COMPILE=ppc_8xx- MAKEALL 4445 4446With the above settings build objects are saved in the /tmp/build, 4447log files are saved in the /tmp/log and the source tree remains clean 4448during the whole build process. 4449 4450 4451See also "U-Boot Porting Guide" below. 4452 4453 4454Monitor Commands - Overview: 4455============================ 4456 4457go - start application at address 'addr' 4458run - run commands in an environment variable 4459bootm - boot application image from memory 4460bootp - boot image via network using BootP/TFTP protocol 4461bootz - boot zImage from memory 4462tftpboot- boot image via network using TFTP protocol 4463 and env variables "ipaddr" and "serverip" 4464 (and eventually "gatewayip") 4465tftpput - upload a file via network using TFTP protocol 4466rarpboot- boot image via network using RARP/TFTP protocol 4467diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 4468loads - load S-Record file over serial line 4469loadb - load binary file over serial line (kermit mode) 4470md - memory display 4471mm - memory modify (auto-incrementing) 4472nm - memory modify (constant address) 4473mw - memory write (fill) 4474cp - memory copy 4475cmp - memory compare 4476crc32 - checksum calculation 4477i2c - I2C sub-system 4478sspi - SPI utility commands 4479base - print or set address offset 4480printenv- print environment variables 4481setenv - set environment variables 4482saveenv - save environment variables to persistent storage 4483protect - enable or disable FLASH write protection 4484erase - erase FLASH memory 4485flinfo - print FLASH memory information 4486nand - NAND memory operations (see doc/README.nand) 4487bdinfo - print Board Info structure 4488iminfo - print header information for application image 4489coninfo - print console devices and informations 4490ide - IDE sub-system 4491loop - infinite loop on address range 4492loopw - infinite write loop on address range 4493mtest - simple RAM test 4494icache - enable or disable instruction cache 4495dcache - enable or disable data cache 4496reset - Perform RESET of the CPU 4497echo - echo args to console 4498version - print monitor version 4499help - print online help 4500? - alias for 'help' 4501 4502 4503Monitor Commands - Detailed Description: 4504======================================== 4505 4506TODO. 4507 4508For now: just type "help <command>". 4509 4510 4511Environment Variables: 4512====================== 4513 4514U-Boot supports user configuration using Environment Variables which 4515can be made persistent by saving to Flash memory. 4516 4517Environment Variables are set using "setenv", printed using 4518"printenv", and saved to Flash using "saveenv". Using "setenv" 4519without a value can be used to delete a variable from the 4520environment. As long as you don't save the environment you are 4521working with an in-memory copy. In case the Flash area containing the 4522environment is erased by accident, a default environment is provided. 4523 4524Some configuration options can be set using Environment Variables. 4525 4526List of environment variables (most likely not complete): 4527 4528 baudrate - see CONFIG_BAUDRATE 4529 4530 bootdelay - see CONFIG_BOOTDELAY 4531 4532 bootcmd - see CONFIG_BOOTCOMMAND 4533 4534 bootargs - Boot arguments when booting an RTOS image 4535 4536 bootfile - Name of the image to load with TFTP 4537 4538 bootm_low - Memory range available for image processing in the bootm 4539 command can be restricted. This variable is given as 4540 a hexadecimal number and defines lowest address allowed 4541 for use by the bootm command. See also "bootm_size" 4542 environment variable. Address defined by "bootm_low" is 4543 also the base of the initial memory mapping for the Linux 4544 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and 4545 bootm_mapsize. 4546 4547 bootm_mapsize - Size of the initial memory mapping for the Linux kernel. 4548 This variable is given as a hexadecimal number and it 4549 defines the size of the memory region starting at base 4550 address bootm_low that is accessible by the Linux kernel 4551 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used 4552 as the default value if it is defined, and bootm_size is 4553 used otherwise. 4554 4555 bootm_size - Memory range available for image processing in the bootm 4556 command can be restricted. This variable is given as 4557 a hexadecimal number and defines the size of the region 4558 allowed for use by the bootm command. See also "bootm_low" 4559 environment variable. 4560 4561 updatefile - Location of the software update file on a TFTP server, used 4562 by the automatic software update feature. Please refer to 4563 documentation in doc/README.update for more details. 4564 4565 autoload - if set to "no" (any string beginning with 'n'), 4566 "bootp" will just load perform a lookup of the 4567 configuration from the BOOTP server, but not try to 4568 load any image using TFTP 4569 4570 autostart - if set to "yes", an image loaded using the "bootp", 4571 "rarpboot", "tftpboot" or "diskboot" commands will 4572 be automatically started (by internally calling 4573 "bootm") 4574 4575 If set to "no", a standalone image passed to the 4576 "bootm" command will be copied to the load address 4577 (and eventually uncompressed), but NOT be started. 4578 This can be used to load and uncompress arbitrary 4579 data. 4580 4581 fdt_high - if set this restricts the maximum address that the 4582 flattened device tree will be copied into upon boot. 4583 For example, if you have a system with 1 GB memory 4584 at physical address 0x10000000, while Linux kernel 4585 only recognizes the first 704 MB as low memory, you 4586 may need to set fdt_high as 0x3C000000 to have the 4587 device tree blob be copied to the maximum address 4588 of the 704 MB low memory, so that Linux kernel can 4589 access it during the boot procedure. 4590 4591 If this is set to the special value 0xFFFFFFFF then 4592 the fdt will not be copied at all on boot. For this 4593 to work it must reside in writable memory, have 4594 sufficient padding on the end of it for u-boot to 4595 add the information it needs into it, and the memory 4596 must be accessible by the kernel. 4597 4598 fdtcontroladdr- if set this is the address of the control flattened 4599 device tree used by U-Boot when CONFIG_OF_CONTROL is 4600 defined. 4601 4602 i2cfast - (PPC405GP|PPC405EP only) 4603 if set to 'y' configures Linux I2C driver for fast 4604 mode (400kHZ). This environment variable is used in 4605 initialization code. So, for changes to be effective 4606 it must be saved and board must be reset. 4607 4608 initrd_high - restrict positioning of initrd images: 4609 If this variable is not set, initrd images will be 4610 copied to the highest possible address in RAM; this 4611 is usually what you want since it allows for 4612 maximum initrd size. If for some reason you want to 4613 make sure that the initrd image is loaded below the 4614 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment 4615 variable to a value of "no" or "off" or "0". 4616 Alternatively, you can set it to a maximum upper 4617 address to use (U-Boot will still check that it 4618 does not overwrite the U-Boot stack and data). 4619 4620 For instance, when you have a system with 16 MB 4621 RAM, and want to reserve 4 MB from use by Linux, 4622 you can do this by adding "mem=12M" to the value of 4623 the "bootargs" variable. However, now you must make 4624 sure that the initrd image is placed in the first 4625 12 MB as well - this can be done with 4626 4627 setenv initrd_high 00c00000 4628 4629 If you set initrd_high to 0xFFFFFFFF, this is an 4630 indication to U-Boot that all addresses are legal 4631 for the Linux kernel, including addresses in flash 4632 memory. In this case U-Boot will NOT COPY the 4633 ramdisk at all. This may be useful to reduce the 4634 boot time on your system, but requires that this 4635 feature is supported by your Linux kernel. 4636 4637 ipaddr - IP address; needed for tftpboot command 4638 4639 loadaddr - Default load address for commands like "bootp", 4640 "rarpboot", "tftpboot", "loadb" or "diskboot" 4641 4642 loads_echo - see CONFIG_LOADS_ECHO 4643 4644 serverip - TFTP server IP address; needed for tftpboot command 4645 4646 bootretry - see CONFIG_BOOT_RETRY_TIME 4647 4648 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 4649 4650 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 4651 4652 ethprime - controls which interface is used first. 4653 4654 ethact - controls which interface is currently active. 4655 For example you can do the following 4656 4657 => setenv ethact FEC 4658 => ping 192.168.0.1 # traffic sent on FEC 4659 => setenv ethact SCC 4660 => ping 10.0.0.1 # traffic sent on SCC 4661 4662 ethrotate - When set to "no" U-Boot does not go through all 4663 available network interfaces. 4664 It just stays at the currently selected interface. 4665 4666 netretry - When set to "no" each network operation will 4667 either succeed or fail without retrying. 4668 When set to "once" the network operation will 4669 fail when all the available network interfaces 4670 are tried once without success. 4671 Useful on scripts which control the retry operation 4672 themselves. 4673 4674 npe_ucode - set load address for the NPE microcode 4675 4676 silent_linux - If set then linux will be told to boot silently, by 4677 changing the console to be empty. If "yes" it will be 4678 made silent. If "no" it will not be made silent. If 4679 unset, then it will be made silent if the U-Boot console 4680 is silent. 4681 4682 tftpsrcport - If this is set, the value is used for TFTP's 4683 UDP source port. 4684 4685 tftpdstport - If this is set, the value is used for TFTP's UDP 4686 destination port instead of the Well Know Port 69. 4687 4688 tftpblocksize - Block size to use for TFTP transfers; if not set, 4689 we use the TFTP server's default block size 4690 4691 tftptimeout - Retransmission timeout for TFTP packets (in milli- 4692 seconds, minimum value is 1000 = 1 second). Defines 4693 when a packet is considered to be lost so it has to 4694 be retransmitted. The default is 5000 = 5 seconds. 4695 Lowering this value may make downloads succeed 4696 faster in networks with high packet loss rates or 4697 with unreliable TFTP servers. 4698 4699 vlan - When set to a value < 4095 the traffic over 4700 Ethernet is encapsulated/received over 802.1q 4701 VLAN tagged frames. 4702 4703The following image location variables contain the location of images 4704used in booting. The "Image" column gives the role of the image and is 4705not an environment variable name. The other columns are environment 4706variable names. "File Name" gives the name of the file on a TFTP 4707server, "RAM Address" gives the location in RAM the image will be 4708loaded to, and "Flash Location" gives the image's address in NOR 4709flash or offset in NAND flash. 4710 4711*Note* - these variables don't have to be defined for all boards, some 4712boards currenlty use other variables for these purposes, and some 4713boards use these variables for other purposes. 4714 4715Image File Name RAM Address Flash Location 4716----- --------- ----------- -------------- 4717u-boot u-boot u-boot_addr_r u-boot_addr 4718Linux kernel bootfile kernel_addr_r kernel_addr 4719device tree blob fdtfile fdt_addr_r fdt_addr 4720ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr 4721 4722The following environment variables may be used and automatically 4723updated by the network boot commands ("bootp" and "rarpboot"), 4724depending the information provided by your boot server: 4725 4726 bootfile - see above 4727 dnsip - IP address of your Domain Name Server 4728 dnsip2 - IP address of your secondary Domain Name Server 4729 gatewayip - IP address of the Gateway (Router) to use 4730 hostname - Target hostname 4731 ipaddr - see above 4732 netmask - Subnet Mask 4733 rootpath - Pathname of the root filesystem on the NFS server 4734 serverip - see above 4735 4736 4737There are two special Environment Variables: 4738 4739 serial# - contains hardware identification information such 4740 as type string and/or serial number 4741 ethaddr - Ethernet address 4742 4743These variables can be set only once (usually during manufacturing of 4744the board). U-Boot refuses to delete or overwrite these variables 4745once they have been set once. 4746 4747 4748Further special Environment Variables: 4749 4750 ver - Contains the U-Boot version string as printed 4751 with the "version" command. This variable is 4752 readonly (see CONFIG_VERSION_VARIABLE). 4753 4754 4755Please note that changes to some configuration parameters may take 4756only effect after the next boot (yes, that's just like Windoze :-). 4757 4758 4759Callback functions for environment variables: 4760--------------------------------------------- 4761 4762For some environment variables, the behavior of u-boot needs to change 4763when their values are changed. This functionailty allows functions to 4764be associated with arbitrary variables. On creation, overwrite, or 4765deletion, the callback will provide the opportunity for some side 4766effect to happen or for the change to be rejected. 4767 4768The callbacks are named and associated with a function using the 4769U_BOOT_ENV_CALLBACK macro in your board or driver code. 4770 4771These callbacks are associated with variables in one of two ways. The 4772static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC 4773in the board configuration to a string that defines a list of 4774associations. The list must be in the following format: 4775 4776 entry = variable_name[:callback_name] 4777 list = entry[,list] 4778 4779If the callback name is not specified, then the callback is deleted. 4780Spaces are also allowed anywhere in the list. 4781 4782Callbacks can also be associated by defining the ".callbacks" variable 4783with the same list format above. Any association in ".callbacks" will 4784override any association in the static list. You can define 4785CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the 4786".callbacks" envirnoment variable in the default or embedded environment. 4787 4788 4789Command Line Parsing: 4790===================== 4791 4792There are two different command line parsers available with U-Boot: 4793the old "simple" one, and the much more powerful "hush" shell: 4794 4795Old, simple command line parser: 4796-------------------------------- 4797 4798- supports environment variables (through setenv / saveenv commands) 4799- several commands on one line, separated by ';' 4800- variable substitution using "... ${name} ..." syntax 4801- special characters ('$', ';') can be escaped by prefixing with '\', 4802 for example: 4803 setenv bootcmd bootm \${address} 4804- You can also escape text by enclosing in single apostrophes, for example: 4805 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off' 4806 4807Hush shell: 4808----------- 4809 4810- similar to Bourne shell, with control structures like 4811 if...then...else...fi, for...do...done; while...do...done, 4812 until...do...done, ... 4813- supports environment ("global") variables (through setenv / saveenv 4814 commands) and local shell variables (through standard shell syntax 4815 "name=value"); only environment variables can be used with "run" 4816 command 4817 4818General rules: 4819-------------- 4820 4821(1) If a command line (or an environment variable executed by a "run" 4822 command) contains several commands separated by semicolon, and 4823 one of these commands fails, then the remaining commands will be 4824 executed anyway. 4825 4826(2) If you execute several variables with one call to run (i. e. 4827 calling run with a list of variables as arguments), any failing 4828 command will cause "run" to terminate, i. e. the remaining 4829 variables are not executed. 4830 4831Note for Redundant Ethernet Interfaces: 4832======================================= 4833 4834Some boards come with redundant Ethernet interfaces; U-Boot supports 4835such configurations and is capable of automatic selection of a 4836"working" interface when needed. MAC assignment works as follows: 4837 4838Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 4839MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 4840"eth1addr" (=>eth1), "eth2addr", ... 4841 4842If the network interface stores some valid MAC address (for instance 4843in SROM), this is used as default address if there is NO correspon- 4844ding setting in the environment; if the corresponding environment 4845variable is set, this overrides the settings in the card; that means: 4846 4847o If the SROM has a valid MAC address, and there is no address in the 4848 environment, the SROM's address is used. 4849 4850o If there is no valid address in the SROM, and a definition in the 4851 environment exists, then the value from the environment variable is 4852 used. 4853 4854o If both the SROM and the environment contain a MAC address, and 4855 both addresses are the same, this MAC address is used. 4856 4857o If both the SROM and the environment contain a MAC address, and the 4858 addresses differ, the value from the environment is used and a 4859 warning is printed. 4860 4861o If neither SROM nor the environment contain a MAC address, an error 4862 is raised. 4863 4864If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses 4865will be programmed into hardware as part of the initialization process. This 4866may be skipped by setting the appropriate 'ethmacskip' environment variable. 4867The naming convention is as follows: 4868"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc. 4869 4870Image Formats: 4871============== 4872 4873U-Boot is capable of booting (and performing other auxiliary operations on) 4874images in two formats: 4875 4876New uImage format (FIT) 4877----------------------- 4878 4879Flexible and powerful format based on Flattened Image Tree -- FIT (similar 4880to Flattened Device Tree). It allows the use of images with multiple 4881components (several kernels, ramdisks, etc.), with contents protected by 4882SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory. 4883 4884 4885Old uImage format 4886----------------- 4887 4888Old image format is based on binary files which can be basically anything, 4889preceded by a special header; see the definitions in include/image.h for 4890details; basically, the header defines the following image properties: 4891 4892* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 4893 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 4894 LynxOS, pSOS, QNX, RTEMS, INTEGRITY; 4895 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS, 4896 INTEGRITY). 4897* Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86, 4898 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 4899 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC). 4900* Compression Type (uncompressed, gzip, bzip2) 4901* Load Address 4902* Entry Point 4903* Image Name 4904* Image Timestamp 4905 4906The header is marked by a special Magic Number, and both the header 4907and the data portions of the image are secured against corruption by 4908CRC32 checksums. 4909 4910 4911Linux Support: 4912============== 4913 4914Although U-Boot should support any OS or standalone application 4915easily, the main focus has always been on Linux during the design of 4916U-Boot. 4917 4918U-Boot includes many features that so far have been part of some 4919special "boot loader" code within the Linux kernel. Also, any 4920"initrd" images to be used are no longer part of one big Linux image; 4921instead, kernel and "initrd" are separate images. This implementation 4922serves several purposes: 4923 4924- the same features can be used for other OS or standalone 4925 applications (for instance: using compressed images to reduce the 4926 Flash memory footprint) 4927 4928- it becomes much easier to port new Linux kernel versions because 4929 lots of low-level, hardware dependent stuff are done by U-Boot 4930 4931- the same Linux kernel image can now be used with different "initrd" 4932 images; of course this also means that different kernel images can 4933 be run with the same "initrd". This makes testing easier (you don't 4934 have to build a new "zImage.initrd" Linux image when you just 4935 change a file in your "initrd"). Also, a field-upgrade of the 4936 software is easier now. 4937 4938 4939Linux HOWTO: 4940============ 4941 4942Porting Linux to U-Boot based systems: 4943--------------------------------------- 4944 4945U-Boot cannot save you from doing all the necessary modifications to 4946configure the Linux device drivers for use with your target hardware 4947(no, we don't intend to provide a full virtual machine interface to 4948Linux :-). 4949 4950But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot). 4951 4952Just make sure your machine specific header file (for instance 4953include/asm-ppc/tqm8xx.h) includes the same definition of the Board 4954Information structure as we define in include/asm-<arch>/u-boot.h, 4955and make sure that your definition of IMAP_ADDR uses the same value 4956as your U-Boot configuration in CONFIG_SYS_IMMR. 4957 4958 4959Configuring the Linux kernel: 4960----------------------------- 4961 4962No specific requirements for U-Boot. Make sure you have some root 4963device (initial ramdisk, NFS) for your target system. 4964 4965 4966Building a Linux Image: 4967----------------------- 4968 4969With U-Boot, "normal" build targets like "zImage" or "bzImage" are 4970not used. If you use recent kernel source, a new build target 4971"uImage" will exist which automatically builds an image usable by 4972U-Boot. Most older kernels also have support for a "pImage" target, 4973which was introduced for our predecessor project PPCBoot and uses a 4974100% compatible format. 4975 4976Example: 4977 4978 make TQM850L_config 4979 make oldconfig 4980 make dep 4981 make uImage 4982 4983The "uImage" build target uses a special tool (in 'tools/mkimage') to 4984encapsulate a compressed Linux kernel image with header information, 4985CRC32 checksum etc. for use with U-Boot. This is what we are doing: 4986 4987* build a standard "vmlinux" kernel image (in ELF binary format): 4988 4989* convert the kernel into a raw binary image: 4990 4991 ${CROSS_COMPILE}-objcopy -O binary \ 4992 -R .note -R .comment \ 4993 -S vmlinux linux.bin 4994 4995* compress the binary image: 4996 4997 gzip -9 linux.bin 4998 4999* package compressed binary image for U-Boot: 5000 5001 mkimage -A ppc -O linux -T kernel -C gzip \ 5002 -a 0 -e 0 -n "Linux Kernel Image" \ 5003 -d linux.bin.gz uImage 5004 5005 5006The "mkimage" tool can also be used to create ramdisk images for use 5007with U-Boot, either separated from the Linux kernel image, or 5008combined into one file. "mkimage" encapsulates the images with a 64 5009byte header containing information about target architecture, 5010operating system, image type, compression method, entry points, time 5011stamp, CRC32 checksums, etc. 5012 5013"mkimage" can be called in two ways: to verify existing images and 5014print the header information, or to build new images. 5015 5016In the first form (with "-l" option) mkimage lists the information 5017contained in the header of an existing U-Boot image; this includes 5018checksum verification: 5019 5020 tools/mkimage -l image 5021 -l ==> list image header information 5022 5023The second form (with "-d" option) is used to build a U-Boot image 5024from a "data file" which is used as image payload: 5025 5026 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 5027 -n name -d data_file image 5028 -A ==> set architecture to 'arch' 5029 -O ==> set operating system to 'os' 5030 -T ==> set image type to 'type' 5031 -C ==> set compression type 'comp' 5032 -a ==> set load address to 'addr' (hex) 5033 -e ==> set entry point to 'ep' (hex) 5034 -n ==> set image name to 'name' 5035 -d ==> use image data from 'datafile' 5036 5037Right now, all Linux kernels for PowerPC systems use the same load 5038address (0x00000000), but the entry point address depends on the 5039kernel version: 5040 5041- 2.2.x kernels have the entry point at 0x0000000C, 5042- 2.3.x and later kernels have the entry point at 0x00000000. 5043 5044So a typical call to build a U-Boot image would read: 5045 5046 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 5047 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 5048 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \ 5049 > examples/uImage.TQM850L 5050 Image Name: 2.4.4 kernel for TQM850L 5051 Created: Wed Jul 19 02:34:59 2000 5052 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5053 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 5054 Load Address: 0x00000000 5055 Entry Point: 0x00000000 5056 5057To verify the contents of the image (or check for corruption): 5058 5059 -> tools/mkimage -l examples/uImage.TQM850L 5060 Image Name: 2.4.4 kernel for TQM850L 5061 Created: Wed Jul 19 02:34:59 2000 5062 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5063 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 5064 Load Address: 0x00000000 5065 Entry Point: 0x00000000 5066 5067NOTE: for embedded systems where boot time is critical you can trade 5068speed for memory and install an UNCOMPRESSED image instead: this 5069needs more space in Flash, but boots much faster since it does not 5070need to be uncompressed: 5071 5072 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz 5073 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 5074 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 5075 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \ 5076 > examples/uImage.TQM850L-uncompressed 5077 Image Name: 2.4.4 kernel for TQM850L 5078 Created: Wed Jul 19 02:34:59 2000 5079 Image Type: PowerPC Linux Kernel Image (uncompressed) 5080 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 5081 Load Address: 0x00000000 5082 Entry Point: 0x00000000 5083 5084 5085Similar you can build U-Boot images from a 'ramdisk.image.gz' file 5086when your kernel is intended to use an initial ramdisk: 5087 5088 -> tools/mkimage -n 'Simple Ramdisk Image' \ 5089 > -A ppc -O linux -T ramdisk -C gzip \ 5090 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 5091 Image Name: Simple Ramdisk Image 5092 Created: Wed Jan 12 14:01:50 2000 5093 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5094 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 5095 Load Address: 0x00000000 5096 Entry Point: 0x00000000 5097 5098 5099Installing a Linux Image: 5100------------------------- 5101 5102To downloading a U-Boot image over the serial (console) interface, 5103you must convert the image to S-Record format: 5104 5105 objcopy -I binary -O srec examples/image examples/image.srec 5106 5107The 'objcopy' does not understand the information in the U-Boot 5108image header, so the resulting S-Record file will be relative to 5109address 0x00000000. To load it to a given address, you need to 5110specify the target address as 'offset' parameter with the 'loads' 5111command. 5112 5113Example: install the image to address 0x40100000 (which on the 5114TQM8xxL is in the first Flash bank): 5115 5116 => erase 40100000 401FFFFF 5117 5118 .......... done 5119 Erased 8 sectors 5120 5121 => loads 40100000 5122 ## Ready for S-Record download ... 5123 ~>examples/image.srec 5124 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 5125 ... 5126 15989 15990 15991 15992 5127 [file transfer complete] 5128 [connected] 5129 ## Start Addr = 0x00000000 5130 5131 5132You can check the success of the download using the 'iminfo' command; 5133this includes a checksum verification so you can be sure no data 5134corruption happened: 5135 5136 => imi 40100000 5137 5138 ## Checking Image at 40100000 ... 5139 Image Name: 2.2.13 for initrd on TQM850L 5140 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5141 Data Size: 335725 Bytes = 327 kB = 0 MB 5142 Load Address: 00000000 5143 Entry Point: 0000000c 5144 Verifying Checksum ... OK 5145 5146 5147Boot Linux: 5148----------- 5149 5150The "bootm" command is used to boot an application that is stored in 5151memory (RAM or Flash). In case of a Linux kernel image, the contents 5152of the "bootargs" environment variable is passed to the kernel as 5153parameters. You can check and modify this variable using the 5154"printenv" and "setenv" commands: 5155 5156 5157 => printenv bootargs 5158 bootargs=root=/dev/ram 5159 5160 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5161 5162 => printenv bootargs 5163 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5164 5165 => bootm 40020000 5166 ## Booting Linux kernel at 40020000 ... 5167 Image Name: 2.2.13 for NFS on TQM850L 5168 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5169 Data Size: 381681 Bytes = 372 kB = 0 MB 5170 Load Address: 00000000 5171 Entry Point: 0000000c 5172 Verifying Checksum ... OK 5173 Uncompressing Kernel Image ... OK 5174 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 5175 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5176 time_init: decrementer frequency = 187500000/60 5177 Calibrating delay loop... 49.77 BogoMIPS 5178 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 5179 ... 5180 5181If you want to boot a Linux kernel with initial RAM disk, you pass 5182the memory addresses of both the kernel and the initrd image (PPBCOOT 5183format!) to the "bootm" command: 5184 5185 => imi 40100000 40200000 5186 5187 ## Checking Image at 40100000 ... 5188 Image Name: 2.2.13 for initrd on TQM850L 5189 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5190 Data Size: 335725 Bytes = 327 kB = 0 MB 5191 Load Address: 00000000 5192 Entry Point: 0000000c 5193 Verifying Checksum ... OK 5194 5195 ## Checking Image at 40200000 ... 5196 Image Name: Simple Ramdisk Image 5197 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5198 Data Size: 566530 Bytes = 553 kB = 0 MB 5199 Load Address: 00000000 5200 Entry Point: 00000000 5201 Verifying Checksum ... OK 5202 5203 => bootm 40100000 40200000 5204 ## Booting Linux kernel at 40100000 ... 5205 Image Name: 2.2.13 for initrd on TQM850L 5206 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5207 Data Size: 335725 Bytes = 327 kB = 0 MB 5208 Load Address: 00000000 5209 Entry Point: 0000000c 5210 Verifying Checksum ... OK 5211 Uncompressing Kernel Image ... OK 5212 ## Loading RAMDisk Image at 40200000 ... 5213 Image Name: Simple Ramdisk Image 5214 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5215 Data Size: 566530 Bytes = 553 kB = 0 MB 5216 Load Address: 00000000 5217 Entry Point: 00000000 5218 Verifying Checksum ... OK 5219 Loading Ramdisk ... OK 5220 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 5221 Boot arguments: root=/dev/ram 5222 time_init: decrementer frequency = 187500000/60 5223 Calibrating delay loop... 49.77 BogoMIPS 5224 ... 5225 RAMDISK: Compressed image found at block 0 5226 VFS: Mounted root (ext2 filesystem). 5227 5228 bash# 5229 5230Boot Linux and pass a flat device tree: 5231----------- 5232 5233First, U-Boot must be compiled with the appropriate defines. See the section 5234titled "Linux Kernel Interface" above for a more in depth explanation. The 5235following is an example of how to start a kernel and pass an updated 5236flat device tree: 5237 5238=> print oftaddr 5239oftaddr=0x300000 5240=> print oft 5241oft=oftrees/mpc8540ads.dtb 5242=> tftp $oftaddr $oft 5243Speed: 1000, full duplex 5244Using TSEC0 device 5245TFTP from server 192.168.1.1; our IP address is 192.168.1.101 5246Filename 'oftrees/mpc8540ads.dtb'. 5247Load address: 0x300000 5248Loading: # 5249done 5250Bytes transferred = 4106 (100a hex) 5251=> tftp $loadaddr $bootfile 5252Speed: 1000, full duplex 5253Using TSEC0 device 5254TFTP from server 192.168.1.1; our IP address is 192.168.1.2 5255Filename 'uImage'. 5256Load address: 0x200000 5257Loading:############ 5258done 5259Bytes transferred = 1029407 (fb51f hex) 5260=> print loadaddr 5261loadaddr=200000 5262=> print oftaddr 5263oftaddr=0x300000 5264=> bootm $loadaddr - $oftaddr 5265## Booting image at 00200000 ... 5266 Image Name: Linux-2.6.17-dirty 5267 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5268 Data Size: 1029343 Bytes = 1005.2 kB 5269 Load Address: 00000000 5270 Entry Point: 00000000 5271 Verifying Checksum ... OK 5272 Uncompressing Kernel Image ... OK 5273Booting using flat device tree at 0x300000 5274Using MPC85xx ADS machine description 5275Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb 5276[snip] 5277 5278 5279More About U-Boot Image Types: 5280------------------------------ 5281 5282U-Boot supports the following image types: 5283 5284 "Standalone Programs" are directly runnable in the environment 5285 provided by U-Boot; it is expected that (if they behave 5286 well) you can continue to work in U-Boot after return from 5287 the Standalone Program. 5288 "OS Kernel Images" are usually images of some Embedded OS which 5289 will take over control completely. Usually these programs 5290 will install their own set of exception handlers, device 5291 drivers, set up the MMU, etc. - this means, that you cannot 5292 expect to re-enter U-Boot except by resetting the CPU. 5293 "RAMDisk Images" are more or less just data blocks, and their 5294 parameters (address, size) are passed to an OS kernel that is 5295 being started. 5296 "Multi-File Images" contain several images, typically an OS 5297 (Linux) kernel image and one or more data images like 5298 RAMDisks. This construct is useful for instance when you want 5299 to boot over the network using BOOTP etc., where the boot 5300 server provides just a single image file, but you want to get 5301 for instance an OS kernel and a RAMDisk image. 5302 5303 "Multi-File Images" start with a list of image sizes, each 5304 image size (in bytes) specified by an "uint32_t" in network 5305 byte order. This list is terminated by an "(uint32_t)0". 5306 Immediately after the terminating 0 follow the images, one by 5307 one, all aligned on "uint32_t" boundaries (size rounded up to 5308 a multiple of 4 bytes). 5309 5310 "Firmware Images" are binary images containing firmware (like 5311 U-Boot or FPGA images) which usually will be programmed to 5312 flash memory. 5313 5314 "Script files" are command sequences that will be executed by 5315 U-Boot's command interpreter; this feature is especially 5316 useful when you configure U-Boot to use a real shell (hush) 5317 as command interpreter. 5318 5319Booting the Linux zImage: 5320------------------------- 5321 5322On some platforms, it's possible to boot Linux zImage. This is done 5323using the "bootz" command. The syntax of "bootz" command is the same 5324as the syntax of "bootm" command. 5325 5326Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply 5327kernel with raw initrd images. The syntax is slightly different, the 5328address of the initrd must be augmented by it's size, in the following 5329format: "<initrd addres>:<initrd size>". 5330 5331 5332Standalone HOWTO: 5333================= 5334 5335One of the features of U-Boot is that you can dynamically load and 5336run "standalone" applications, which can use some resources of 5337U-Boot like console I/O functions or interrupt services. 5338 5339Two simple examples are included with the sources: 5340 5341"Hello World" Demo: 5342------------------- 5343 5344'examples/hello_world.c' contains a small "Hello World" Demo 5345application; it is automatically compiled when you build U-Boot. 5346It's configured to run at address 0x00040004, so you can play with it 5347like that: 5348 5349 => loads 5350 ## Ready for S-Record download ... 5351 ~>examples/hello_world.srec 5352 1 2 3 4 5 6 7 8 9 10 11 ... 5353 [file transfer complete] 5354 [connected] 5355 ## Start Addr = 0x00040004 5356 5357 => go 40004 Hello World! This is a test. 5358 ## Starting application at 0x00040004 ... 5359 Hello World 5360 argc = 7 5361 argv[0] = "40004" 5362 argv[1] = "Hello" 5363 argv[2] = "World!" 5364 argv[3] = "This" 5365 argv[4] = "is" 5366 argv[5] = "a" 5367 argv[6] = "test." 5368 argv[7] = "<NULL>" 5369 Hit any key to exit ... 5370 5371 ## Application terminated, rc = 0x0 5372 5373Another example, which demonstrates how to register a CPM interrupt 5374handler with the U-Boot code, can be found in 'examples/timer.c'. 5375Here, a CPM timer is set up to generate an interrupt every second. 5376The interrupt service routine is trivial, just printing a '.' 5377character, but this is just a demo program. The application can be 5378controlled by the following keys: 5379 5380 ? - print current values og the CPM Timer registers 5381 b - enable interrupts and start timer 5382 e - stop timer and disable interrupts 5383 q - quit application 5384 5385 => loads 5386 ## Ready for S-Record download ... 5387 ~>examples/timer.srec 5388 1 2 3 4 5 6 7 8 9 10 11 ... 5389 [file transfer complete] 5390 [connected] 5391 ## Start Addr = 0x00040004 5392 5393 => go 40004 5394 ## Starting application at 0x00040004 ... 5395 TIMERS=0xfff00980 5396 Using timer 1 5397 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 5398 5399Hit 'b': 5400 [q, b, e, ?] Set interval 1000000 us 5401 Enabling timer 5402Hit '?': 5403 [q, b, e, ?] ........ 5404 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 5405Hit '?': 5406 [q, b, e, ?] . 5407 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 5408Hit '?': 5409 [q, b, e, ?] . 5410 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 5411Hit '?': 5412 [q, b, e, ?] . 5413 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 5414Hit 'e': 5415 [q, b, e, ?] ...Stopping timer 5416Hit 'q': 5417 [q, b, e, ?] ## Application terminated, rc = 0x0 5418 5419 5420Minicom warning: 5421================ 5422 5423Over time, many people have reported problems when trying to use the 5424"minicom" terminal emulation program for serial download. I (wd) 5425consider minicom to be broken, and recommend not to use it. Under 5426Unix, I recommend to use C-Kermit for general purpose use (and 5427especially for kermit binary protocol download ("loadb" command), and 5428use "cu" for S-Record download ("loads" command). See 5429http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3. 5430for help with kermit. 5431 5432 5433Nevertheless, if you absolutely want to use it try adding this 5434configuration to your "File transfer protocols" section: 5435 5436 Name Program Name U/D FullScr IO-Red. Multi 5437 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N 5438 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N 5439 5440 5441NetBSD Notes: 5442============= 5443 5444Starting at version 0.9.2, U-Boot supports NetBSD both as host 5445(build U-Boot) and target system (boots NetBSD/mpc8xx). 5446 5447Building requires a cross environment; it is known to work on 5448NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 5449need gmake since the Makefiles are not compatible with BSD make). 5450Note that the cross-powerpc package does not install include files; 5451attempting to build U-Boot will fail because <machine/ansi.h> is 5452missing. This file has to be installed and patched manually: 5453 5454 # cd /usr/pkg/cross/powerpc-netbsd/include 5455 # mkdir powerpc 5456 # ln -s powerpc machine 5457 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 5458 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 5459 5460Native builds *don't* work due to incompatibilities between native 5461and U-Boot include files. 5462 5463Booting assumes that (the first part of) the image booted is a 5464stage-2 loader which in turn loads and then invokes the kernel 5465proper. Loader sources will eventually appear in the NetBSD source 5466tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 5467meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz 5468 5469 5470Implementation Internals: 5471========================= 5472 5473The following is not intended to be a complete description of every 5474implementation detail. However, it should help to understand the 5475inner workings of U-Boot and make it easier to port it to custom 5476hardware. 5477 5478 5479Initial Stack, Global Data: 5480--------------------------- 5481 5482The implementation of U-Boot is complicated by the fact that U-Boot 5483starts running out of ROM (flash memory), usually without access to 5484system RAM (because the memory controller is not initialized yet). 5485This means that we don't have writable Data or BSS segments, and BSS 5486is not initialized as zero. To be able to get a C environment working 5487at all, we have to allocate at least a minimal stack. Implementation 5488options for this are defined and restricted by the CPU used: Some CPU 5489models provide on-chip memory (like the IMMR area on MPC8xx and 5490MPC826x processors), on others (parts of) the data cache can be 5491locked as (mis-) used as memory, etc. 5492 5493 Chris Hallinan posted a good summary of these issues to the 5494 U-Boot mailing list: 5495 5496 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 5497 From: "Chris Hallinan" <clh@net1plus.com> 5498 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 5499 ... 5500 5501 Correct me if I'm wrong, folks, but the way I understand it 5502 is this: Using DCACHE as initial RAM for Stack, etc, does not 5503 require any physical RAM backing up the cache. The cleverness 5504 is that the cache is being used as a temporary supply of 5505 necessary storage before the SDRAM controller is setup. It's 5506 beyond the scope of this list to explain the details, but you 5507 can see how this works by studying the cache architecture and 5508 operation in the architecture and processor-specific manuals. 5509 5510 OCM is On Chip Memory, which I believe the 405GP has 4K. It 5511 is another option for the system designer to use as an 5512 initial stack/RAM area prior to SDRAM being available. Either 5513 option should work for you. Using CS 4 should be fine if your 5514 board designers haven't used it for something that would 5515 cause you grief during the initial boot! It is frequently not 5516 used. 5517 5518 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere 5519 with your processor/board/system design. The default value 5520 you will find in any recent u-boot distribution in 5521 walnut.h should work for you. I'd set it to a value larger 5522 than your SDRAM module. If you have a 64MB SDRAM module, set 5523 it above 400_0000. Just make sure your board has no resources 5524 that are supposed to respond to that address! That code in 5525 start.S has been around a while and should work as is when 5526 you get the config right. 5527 5528 -Chris Hallinan 5529 DS4.COM, Inc. 5530 5531It is essential to remember this, since it has some impact on the C 5532code for the initialization procedures: 5533 5534* Initialized global data (data segment) is read-only. Do not attempt 5535 to write it. 5536 5537* Do not use any uninitialized global data (or implicitely initialized 5538 as zero data - BSS segment) at all - this is undefined, initiali- 5539 zation is performed later (when relocating to RAM). 5540 5541* Stack space is very limited. Avoid big data buffers or things like 5542 that. 5543 5544Having only the stack as writable memory limits means we cannot use 5545normal global data to share information beween the code. But it 5546turned out that the implementation of U-Boot can be greatly 5547simplified by making a global data structure (gd_t) available to all 5548functions. We could pass a pointer to this data as argument to _all_ 5549functions, but this would bloat the code. Instead we use a feature of 5550the GCC compiler (Global Register Variables) to share the data: we 5551place a pointer (gd) to the global data into a register which we 5552reserve for this purpose. 5553 5554When choosing a register for such a purpose we are restricted by the 5555relevant (E)ABI specifications for the current architecture, and by 5556GCC's implementation. 5557 5558For PowerPC, the following registers have specific use: 5559 R1: stack pointer 5560 R2: reserved for system use 5561 R3-R4: parameter passing and return values 5562 R5-R10: parameter passing 5563 R13: small data area pointer 5564 R30: GOT pointer 5565 R31: frame pointer 5566 5567 (U-Boot also uses R12 as internal GOT pointer. r12 5568 is a volatile register so r12 needs to be reset when 5569 going back and forth between asm and C) 5570 5571 ==> U-Boot will use R2 to hold a pointer to the global data 5572 5573 Note: on PPC, we could use a static initializer (since the 5574 address of the global data structure is known at compile time), 5575 but it turned out that reserving a register results in somewhat 5576 smaller code - although the code savings are not that big (on 5577 average for all boards 752 bytes for the whole U-Boot image, 5578 624 text + 127 data). 5579 5580On Blackfin, the normal C ABI (except for P3) is followed as documented here: 5581 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface 5582 5583 ==> U-Boot will use P3 to hold a pointer to the global data 5584 5585On ARM, the following registers are used: 5586 5587 R0: function argument word/integer result 5588 R1-R3: function argument word 5589 R9: platform specific 5590 R10: stack limit (used only if stack checking is enabled) 5591 R11: argument (frame) pointer 5592 R12: temporary workspace 5593 R13: stack pointer 5594 R14: link register 5595 R15: program counter 5596 5597 ==> U-Boot will use R9 to hold a pointer to the global data 5598 5599 Note: on ARM, only R_ARM_RELATIVE relocations are supported. 5600 5601On Nios II, the ABI is documented here: 5602 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf 5603 5604 ==> U-Boot will use gp to hold a pointer to the global data 5605 5606 Note: on Nios II, we give "-G0" option to gcc and don't use gp 5607 to access small data sections, so gp is free. 5608 5609On NDS32, the following registers are used: 5610 5611 R0-R1: argument/return 5612 R2-R5: argument 5613 R15: temporary register for assembler 5614 R16: trampoline register 5615 R28: frame pointer (FP) 5616 R29: global pointer (GP) 5617 R30: link register (LP) 5618 R31: stack pointer (SP) 5619 PC: program counter (PC) 5620 5621 ==> U-Boot will use R10 to hold a pointer to the global data 5622 5623NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope, 5624or current versions of GCC may "optimize" the code too much. 5625 5626Memory Management: 5627------------------ 5628 5629U-Boot runs in system state and uses physical addresses, i.e. the 5630MMU is not used either for address mapping nor for memory protection. 5631 5632The available memory is mapped to fixed addresses using the memory 5633controller. In this process, a contiguous block is formed for each 5634memory type (Flash, SDRAM, SRAM), even when it consists of several 5635physical memory banks. 5636 5637U-Boot is installed in the first 128 kB of the first Flash bank (on 5638TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 5639booting and sizing and initializing DRAM, the code relocates itself 5640to the upper end of DRAM. Immediately below the U-Boot code some 5641memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN 5642configuration setting]. Below that, a structure with global Board 5643Info data is placed, followed by the stack (growing downward). 5644 5645Additionally, some exception handler code is copied to the low 8 kB 5646of DRAM (0x00000000 ... 0x00001FFF). 5647 5648So a typical memory configuration with 16 MB of DRAM could look like 5649this: 5650 5651 0x0000 0000 Exception Vector code 5652 : 5653 0x0000 1FFF 5654 0x0000 2000 Free for Application Use 5655 : 5656 : 5657 5658 : 5659 : 5660 0x00FB FF20 Monitor Stack (Growing downward) 5661 0x00FB FFAC Board Info Data and permanent copy of global data 5662 0x00FC 0000 Malloc Arena 5663 : 5664 0x00FD FFFF 5665 0x00FE 0000 RAM Copy of Monitor Code 5666 ... eventually: LCD or video framebuffer 5667 ... eventually: pRAM (Protected RAM - unchanged by reset) 5668 0x00FF FFFF [End of RAM] 5669 5670 5671System Initialization: 5672---------------------- 5673 5674In the reset configuration, U-Boot starts at the reset entry point 5675(on most PowerPC systems at address 0x00000100). Because of the reset 5676configuration for CS0# this is a mirror of the onboard Flash memory. 5677To be able to re-map memory U-Boot then jumps to its link address. 5678To be able to implement the initialization code in C, a (small!) 5679initial stack is set up in the internal Dual Ported RAM (in case CPUs 5680which provide such a feature like MPC8xx or MPC8260), or in a locked 5681part of the data cache. After that, U-Boot initializes the CPU core, 5682the caches and the SIU. 5683 5684Next, all (potentially) available memory banks are mapped using a 5685preliminary mapping. For example, we put them on 512 MB boundaries 5686(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 5687on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 5688programmed for SDRAM access. Using the temporary configuration, a 5689simple memory test is run that determines the size of the SDRAM 5690banks. 5691 5692When there is more than one SDRAM bank, and the banks are of 5693different size, the largest is mapped first. For equal size, the first 5694bank (CS2#) is mapped first. The first mapping is always for address 56950x00000000, with any additional banks following immediately to create 5696contiguous memory starting from 0. 5697 5698Then, the monitor installs itself at the upper end of the SDRAM area 5699and allocates memory for use by malloc() and for the global Board 5700Info data; also, the exception vector code is copied to the low RAM 5701pages, and the final stack is set up. 5702 5703Only after this relocation will you have a "normal" C environment; 5704until that you are restricted in several ways, mostly because you are 5705running from ROM, and because the code will have to be relocated to a 5706new address in RAM. 5707 5708 5709U-Boot Porting Guide: 5710---------------------- 5711 5712[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 5713list, October 2002] 5714 5715 5716int main(int argc, char *argv[]) 5717{ 5718 sighandler_t no_more_time; 5719 5720 signal(SIGALRM, no_more_time); 5721 alarm(PROJECT_DEADLINE - toSec (3 * WEEK)); 5722 5723 if (available_money > available_manpower) { 5724 Pay consultant to port U-Boot; 5725 return 0; 5726 } 5727 5728 Download latest U-Boot source; 5729 5730 Subscribe to u-boot mailing list; 5731 5732 if (clueless) 5733 email("Hi, I am new to U-Boot, how do I get started?"); 5734 5735 while (learning) { 5736 Read the README file in the top level directory; 5737 Read http://www.denx.de/twiki/bin/view/DULG/Manual; 5738 Read applicable doc/*.README; 5739 Read the source, Luke; 5740 /* find . -name "*.[chS]" | xargs grep -i <keyword> */ 5741 } 5742 5743 if (available_money > toLocalCurrency ($2500)) 5744 Buy a BDI3000; 5745 else 5746 Add a lot of aggravation and time; 5747 5748 if (a similar board exists) { /* hopefully... */ 5749 cp -a board/<similar> board/<myboard> 5750 cp include/configs/<similar>.h include/configs/<myboard>.h 5751 } else { 5752 Create your own board support subdirectory; 5753 Create your own board include/configs/<myboard>.h file; 5754 } 5755 Edit new board/<myboard> files 5756 Edit new include/configs/<myboard>.h 5757 5758 while (!accepted) { 5759 while (!running) { 5760 do { 5761 Add / modify source code; 5762 } until (compiles); 5763 Debug; 5764 if (clueless) 5765 email("Hi, I am having problems..."); 5766 } 5767 Send patch file to the U-Boot email list; 5768 if (reasonable critiques) 5769 Incorporate improvements from email list code review; 5770 else 5771 Defend code as written; 5772 } 5773 5774 return 0; 5775} 5776 5777void no_more_time (int sig) 5778{ 5779 hire_a_guru(); 5780} 5781 5782 5783Coding Standards: 5784----------------- 5785 5786All contributions to U-Boot should conform to the Linux kernel 5787coding style; see the file "Documentation/CodingStyle" and the script 5788"scripts/Lindent" in your Linux kernel source directory. 5789 5790Source files originating from a different project (for example the 5791MTD subsystem) are generally exempt from these guidelines and are not 5792reformated to ease subsequent migration to newer versions of those 5793sources. 5794 5795Please note that U-Boot is implemented in C (and to some small parts in 5796Assembler); no C++ is used, so please do not use C++ style comments (//) 5797in your code. 5798 5799Please also stick to the following formatting rules: 5800- remove any trailing white space 5801- use TAB characters for indentation and vertical alignment, not spaces 5802- make sure NOT to use DOS '\r\n' line feeds 5803- do not add more than 2 consecutive empty lines to source files 5804- do not add trailing empty lines to source files 5805 5806Submissions which do not conform to the standards may be returned 5807with a request to reformat the changes. 5808 5809 5810Submitting Patches: 5811------------------- 5812 5813Since the number of patches for U-Boot is growing, we need to 5814establish some rules. Submissions which do not conform to these rules 5815may be rejected, even when they contain important and valuable stuff. 5816 5817Please see http://www.denx.de/wiki/U-Boot/Patches for details. 5818 5819Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>; 5820see http://lists.denx.de/mailman/listinfo/u-boot 5821 5822When you send a patch, please include the following information with 5823it: 5824 5825* For bug fixes: a description of the bug and how your patch fixes 5826 this bug. Please try to include a way of demonstrating that the 5827 patch actually fixes something. 5828 5829* For new features: a description of the feature and your 5830 implementation. 5831 5832* A CHANGELOG entry as plaintext (separate from the patch) 5833 5834* For major contributions, your entry to the CREDITS file 5835 5836* When you add support for a new board, don't forget to add a 5837 maintainer e-mail address to the boards.cfg file, too. 5838 5839* If your patch adds new configuration options, don't forget to 5840 document these in the README file. 5841 5842* The patch itself. If you are using git (which is *strongly* 5843 recommended) you can easily generate the patch using the 5844 "git format-patch". If you then use "git send-email" to send it to 5845 the U-Boot mailing list, you will avoid most of the common problems 5846 with some other mail clients. 5847 5848 If you cannot use git, use "diff -purN OLD NEW". If your version of 5849 diff does not support these options, then get the latest version of 5850 GNU diff. 5851 5852 The current directory when running this command shall be the parent 5853 directory of the U-Boot source tree (i. e. please make sure that 5854 your patch includes sufficient directory information for the 5855 affected files). 5856 5857 We prefer patches as plain text. MIME attachments are discouraged, 5858 and compressed attachments must not be used. 5859 5860* If one logical set of modifications affects or creates several 5861 files, all these changes shall be submitted in a SINGLE patch file. 5862 5863* Changesets that contain different, unrelated modifications shall be 5864 submitted as SEPARATE patches, one patch per changeset. 5865 5866 5867Notes: 5868 5869* Before sending the patch, run the MAKEALL script on your patched 5870 source tree and make sure that no errors or warnings are reported 5871 for any of the boards. 5872 5873* Keep your modifications to the necessary minimum: A patch 5874 containing several unrelated changes or arbitrary reformats will be 5875 returned with a request to re-formatting / split it. 5876 5877* If you modify existing code, make sure that your new code does not 5878 add to the memory footprint of the code ;-) Small is beautiful! 5879 When adding new features, these should compile conditionally only 5880 (using #ifdef), and the resulting code with the new feature 5881 disabled must not need more memory than the old code without your 5882 modification. 5883 5884* Remember that there is a size limit of 100 kB per message on the 5885 u-boot mailing list. Bigger patches will be moderated. If they are 5886 reasonable and not too big, they will be acknowledged. But patches 5887 bigger than the size limit should be avoided. 5888