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 file to find out who contributed 38the specific port. In addition, there are various MAINTAINERS files 39scattered throughout the U-Boot source identifying the people or 40companies responsible for various boards and subsystems. 41 42Note: As of August, 2010, there is no longer a CHANGELOG file in the 43actual U-Boot source tree; however, it can be created dynamically 44from the Git log using: 45 46 make CHANGELOG 47 48 49Where to get help: 50================== 51 52In case you have questions about, problems with or contributions for 53U-Boot, you should send a message to the U-Boot mailing list at 54<u-boot@lists.denx.de>. There is also an archive of previous traffic 55on the mailing list - please search the archive before asking FAQ's. 56Please see http://lists.denx.de/pipermail/u-boot and 57http://dir.gmane.org/gmane.comp.boot-loaders.u-boot 58 59 60Where to get source code: 61========================= 62 63The U-Boot source code is maintained in the Git repository at 64git://www.denx.de/git/u-boot.git ; you can browse it online at 65http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary 66 67The "snapshot" links on this page allow you to download tarballs of 68any version you might be interested in. Official releases are also 69available for FTP download from the ftp://ftp.denx.de/pub/u-boot/ 70directory. 71 72Pre-built (and tested) images are available from 73ftp://ftp.denx.de/pub/u-boot/images/ 74 75 76Where we come from: 77=================== 78 79- start from 8xxrom sources 80- create PPCBoot project (http://sourceforge.net/projects/ppcboot) 81- clean up code 82- make it easier to add custom boards 83- make it possible to add other [PowerPC] CPUs 84- extend functions, especially: 85 * Provide extended interface to Linux boot loader 86 * S-Record download 87 * network boot 88 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot 89- create ARMBoot project (http://sourceforge.net/projects/armboot) 90- add other CPU families (starting with ARM) 91- create U-Boot project (http://sourceforge.net/projects/u-boot) 92- current project page: see http://www.denx.de/wiki/U-Boot 93 94 95Names and Spelling: 96=================== 97 98The "official" name of this project is "Das U-Boot". The spelling 99"U-Boot" shall be used in all written text (documentation, comments 100in source files etc.). Example: 101 102 This is the README file for the U-Boot project. 103 104File names etc. shall be based on the string "u-boot". Examples: 105 106 include/asm-ppc/u-boot.h 107 108 #include <asm/u-boot.h> 109 110Variable names, preprocessor constants etc. shall be either based on 111the string "u_boot" or on "U_BOOT". Example: 112 113 U_BOOT_VERSION u_boot_logo 114 IH_OS_U_BOOT u_boot_hush_start 115 116 117Versioning: 118=========== 119 120Starting with the release in October 2008, the names of the releases 121were changed from numerical release numbers without deeper meaning 122into a time stamp based numbering. Regular releases are identified by 123names consisting of the calendar year and month of the release date. 124Additional fields (if present) indicate release candidates or bug fix 125releases in "stable" maintenance trees. 126 127Examples: 128 U-Boot v2009.11 - Release November 2009 129 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree 130 U-Boot v2010.09-rc1 - Release candidate 1 for September 2010 release 131 132 133Directory Hierarchy: 134==================== 135 136/arch Architecture specific files 137 /arc Files generic to ARC architecture 138 /arm Files generic to ARM architecture 139 /avr32 Files generic to AVR32 architecture 140 /m68k Files generic to m68k architecture 141 /microblaze Files generic to microblaze architecture 142 /mips Files generic to MIPS architecture 143 /nds32 Files generic to NDS32 architecture 144 /nios2 Files generic to Altera NIOS2 architecture 145 /openrisc Files generic to OpenRISC architecture 146 /powerpc Files generic to PowerPC architecture 147 /sandbox Files generic to HW-independent "sandbox" 148 /sh Files generic to SH architecture 149 /sparc Files generic to SPARC architecture 150 /x86 Files generic to x86 architecture 151/api Machine/arch independent API for external apps 152/board Board dependent files 153/cmd U-Boot commands functions 154/common Misc architecture independent functions 155/configs Board default configuration files 156/disk Code for disk drive partition handling 157/doc Documentation (don't expect too much) 158/drivers Commonly used device drivers 159/dts Contains Makefile for building internal U-Boot fdt. 160/examples Example code for standalone applications, etc. 161/fs Filesystem code (cramfs, ext2, jffs2, etc.) 162/include Header Files 163/lib Library routines generic to all architectures 164/Licenses Various license files 165/net Networking code 166/post Power On Self Test 167/scripts Various build scripts and Makefiles 168/test Various unit test files 169/tools Tools to build S-Record or U-Boot images, etc. 170 171Software Configuration: 172======================= 173 174Configuration is usually done using C preprocessor defines; the 175rationale behind that is to avoid dead code whenever possible. 176 177There are two classes of configuration variables: 178 179* Configuration _OPTIONS_: 180 These are selectable by the user and have names beginning with 181 "CONFIG_". 182 183* Configuration _SETTINGS_: 184 These depend on the hardware etc. and should not be meddled with if 185 you don't know what you're doing; they have names beginning with 186 "CONFIG_SYS_". 187 188Previously, all configuration was done by hand, which involved creating 189symbolic links and editing configuration files manually. More recently, 190U-Boot has added the Kbuild infrastructure used by the Linux kernel, 191allowing you to use the "make menuconfig" command to configure your 192build. 193 194 195Selection of Processor Architecture and Board Type: 196--------------------------------------------------- 197 198For all supported boards there are ready-to-use default 199configurations available; just type "make <board_name>_defconfig". 200 201Example: For a TQM823L module type: 202 203 cd u-boot 204 make TQM823L_defconfig 205 206Note: If you're looking for the default configuration file for a board 207you're sure used to be there but is now missing, check the file 208doc/README.scrapyard for a list of no longer supported boards. 209 210Sandbox Environment: 211-------------------- 212 213U-Boot can be built natively to run on a Linux host using the 'sandbox' 214board. This allows feature development which is not board- or architecture- 215specific to be undertaken on a native platform. The sandbox is also used to 216run some of U-Boot's tests. 217 218See board/sandbox/README.sandbox for more details. 219 220 221Board Initialisation Flow: 222-------------------------- 223 224This is the intended start-up flow for boards. This should apply for both 225SPL and U-Boot proper (i.e. they both follow the same rules). 226 227Note: "SPL" stands for "Secondary Program Loader," which is explained in 228more detail later in this file. 229 230At present, SPL mostly uses a separate code path, but the function names 231and roles of each function are the same. Some boards or architectures 232may not conform to this. At least most ARM boards which use 233CONFIG_SPL_FRAMEWORK conform to this. 234 235Execution typically starts with an architecture-specific (and possibly 236CPU-specific) start.S file, such as: 237 238 - arch/arm/cpu/armv7/start.S 239 - arch/powerpc/cpu/mpc83xx/start.S 240 - arch/mips/cpu/start.S 241 242and so on. From there, three functions are called; the purpose and 243limitations of each of these functions are described below. 244 245lowlevel_init(): 246 - purpose: essential init to permit execution to reach board_init_f() 247 - no global_data or BSS 248 - there is no stack (ARMv7 may have one but it will soon be removed) 249 - must not set up SDRAM or use console 250 - must only do the bare minimum to allow execution to continue to 251 board_init_f() 252 - this is almost never needed 253 - return normally from this function 254 255board_init_f(): 256 - purpose: set up the machine ready for running board_init_r(): 257 i.e. SDRAM and serial UART 258 - global_data is available 259 - stack is in SRAM 260 - BSS is not available, so you cannot use global/static variables, 261 only stack variables and global_data 262 263 Non-SPL-specific notes: 264 - dram_init() is called to set up DRAM. If already done in SPL this 265 can do nothing 266 267 SPL-specific notes: 268 - you can override the entire board_init_f() function with your own 269 version as needed. 270 - preloader_console_init() can be called here in extremis 271 - should set up SDRAM, and anything needed to make the UART work 272 - these is no need to clear BSS, it will be done by crt0.S 273 - must return normally from this function (don't call board_init_r() 274 directly) 275 276Here the BSS is cleared. For SPL, if CONFIG_SPL_STACK_R is defined, then at 277this point the stack and global_data are relocated to below 278CONFIG_SPL_STACK_R_ADDR. For non-SPL, U-Boot is relocated to run at the top of 279memory. 280 281board_init_r(): 282 - purpose: main execution, common code 283 - global_data is available 284 - SDRAM is available 285 - BSS is available, all static/global variables can be used 286 - execution eventually continues to main_loop() 287 288 Non-SPL-specific notes: 289 - U-Boot is relocated to the top of memory and is now running from 290 there. 291 292 SPL-specific notes: 293 - stack is optionally in SDRAM, if CONFIG_SPL_STACK_R is defined and 294 CONFIG_SPL_STACK_R_ADDR points into SDRAM 295 - preloader_console_init() can be called here - typically this is 296 done by defining CONFIG_SPL_BOARD_INIT and then supplying a 297 spl_board_init() function containing this call 298 - loads U-Boot or (in falcon mode) Linux 299 300 301 302Configuration Options: 303---------------------- 304 305Configuration depends on the combination of board and CPU type; all 306such information is kept in a configuration file 307"include/configs/<board_name>.h". 308 309Example: For a TQM823L module, all configuration settings are in 310"include/configs/TQM823L.h". 311 312 313Many of the options are named exactly as the corresponding Linux 314kernel configuration options. The intention is to make it easier to 315build a config tool - later. 316 317 318The following options need to be configured: 319 320- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX. 321 322- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS. 323 324- CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined) 325 Define exactly one, e.g. CONFIG_ATSTK1002 326 327- Marvell Family Member 328 CONFIG_SYS_MVFS - define it if you want to enable 329 multiple fs option at one time 330 for marvell soc family 331 332- 8xx CPU Options: (if using an MPC8xx CPU) 333 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if 334 get_gclk_freq() cannot work 335 e.g. if there is no 32KHz 336 reference PIT/RTC clock 337 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK 338 or XTAL/EXTAL) 339 340- 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU): 341 CONFIG_SYS_8xx_CPUCLK_MIN 342 CONFIG_SYS_8xx_CPUCLK_MAX 343 CONFIG_8xx_CPUCLK_DEFAULT 344 See doc/README.MPC866 345 346 CONFIG_SYS_MEASURE_CPUCLK 347 348 Define this to measure the actual CPU clock instead 349 of relying on the correctness of the configured 350 values. Mostly useful for board bringup to make sure 351 the PLL is locked at the intended frequency. Note 352 that this requires a (stable) reference clock (32 kHz 353 RTC clock or CONFIG_SYS_8XX_XIN) 354 355 CONFIG_SYS_DELAYED_ICACHE 356 357 Define this option if you want to enable the 358 ICache only when Code runs from RAM. 359 360- 85xx CPU Options: 361 CONFIG_SYS_PPC64 362 363 Specifies that the core is a 64-bit PowerPC implementation (implements 364 the "64" category of the Power ISA). This is necessary for ePAPR 365 compliance, among other possible reasons. 366 367 CONFIG_SYS_FSL_TBCLK_DIV 368 369 Defines the core time base clock divider ratio compared to the 370 system clock. On most PQ3 devices this is 8, on newer QorIQ 371 devices it can be 16 or 32. The ratio varies from SoC to Soc. 372 373 CONFIG_SYS_FSL_PCIE_COMPAT 374 375 Defines the string to utilize when trying to match PCIe device 376 tree nodes for the given platform. 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 required during NOR boot. 401 402 CONFIG_A008044_WORKAROUND 403 Enables a workaround for T1040/T1042 erratum A008044. It is only 404 required during NAND boot and valid for Rev 1.0 SoC revision 405 406 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY 407 408 This is the value to write into CCSR offset 0x18600 409 according to the A004510 workaround. 410 411 CONFIG_SYS_FSL_DSP_DDR_ADDR 412 This value denotes start offset of DDR memory which is 413 connected exclusively to the DSP cores. 414 415 CONFIG_SYS_FSL_DSP_M2_RAM_ADDR 416 This value denotes start offset of M2 memory 417 which is directly connected to the DSP core. 418 419 CONFIG_SYS_FSL_DSP_M3_RAM_ADDR 420 This value denotes start offset of M3 memory which is directly 421 connected to the DSP core. 422 423 CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT 424 This value denotes start offset of DSP CCSR space. 425 426 CONFIG_SYS_FSL_SINGLE_SOURCE_CLK 427 Single Source Clock is clocking mode present in some of FSL SoC's. 428 In this mode, a single differential clock is used to supply 429 clocks to the sysclock, ddrclock and usbclock. 430 431 CONFIG_SYS_CPC_REINIT_F 432 This CONFIG is defined when the CPC is configured as SRAM at the 433 time of U-Boot entry and is required to be re-initialized. 434 435 CONFIG_DEEP_SLEEP 436 Indicates this SoC supports deep sleep feature. If deep sleep is 437 supported, core will start to execute uboot when wakes up. 438 439- Generic CPU options: 440 CONFIG_SYS_GENERIC_GLOBAL_DATA 441 Defines global data is initialized in generic board board_init_f(). 442 If this macro is defined, global data is created and cleared in 443 generic board board_init_f(). Without this macro, architecture/board 444 should initialize global data before calling board_init_f(). 445 446 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN 447 448 Defines the endianess of the CPU. Implementation of those 449 values is arch specific. 450 451 CONFIG_SYS_FSL_DDR 452 Freescale DDR driver in use. This type of DDR controller is 453 found in mpc83xx, mpc85xx, mpc86xx as well as some ARM core 454 SoCs. 455 456 CONFIG_SYS_FSL_DDR_ADDR 457 Freescale DDR memory-mapped register base. 458 459 CONFIG_SYS_FSL_DDR_EMU 460 Specify emulator support for DDR. Some DDR features such as 461 deskew training are not available. 462 463 CONFIG_SYS_FSL_DDRC_GEN1 464 Freescale DDR1 controller. 465 466 CONFIG_SYS_FSL_DDRC_GEN2 467 Freescale DDR2 controller. 468 469 CONFIG_SYS_FSL_DDRC_GEN3 470 Freescale DDR3 controller. 471 472 CONFIG_SYS_FSL_DDRC_GEN4 473 Freescale DDR4 controller. 474 475 CONFIG_SYS_FSL_DDRC_ARM_GEN3 476 Freescale DDR3 controller for ARM-based SoCs. 477 478 CONFIG_SYS_FSL_DDR1 479 Board config to use DDR1. It can be enabled for SoCs with 480 Freescale DDR1 or DDR2 controllers, depending on the board 481 implemetation. 482 483 CONFIG_SYS_FSL_DDR2 484 Board config to use DDR2. It can be enabled for SoCs with 485 Freescale DDR2 or DDR3 controllers, depending on the board 486 implementation. 487 488 CONFIG_SYS_FSL_DDR3 489 Board config to use DDR3. It can be enabled for SoCs with 490 Freescale DDR3 or DDR3L controllers. 491 492 CONFIG_SYS_FSL_DDR3L 493 Board config to use DDR3L. It can be enabled for SoCs with 494 DDR3L controllers. 495 496 CONFIG_SYS_FSL_DDR4 497 Board config to use DDR4. It can be enabled for SoCs with 498 DDR4 controllers. 499 500 CONFIG_SYS_FSL_IFC_BE 501 Defines the IFC controller register space as Big Endian 502 503 CONFIG_SYS_FSL_IFC_LE 504 Defines the IFC controller register space as Little Endian 505 506 CONFIG_SYS_FSL_IFC_CLK_DIV 507 Defines divider of platform clock(clock input to IFC controller). 508 509 CONFIG_SYS_FSL_LBC_CLK_DIV 510 Defines divider of platform clock(clock input to eLBC controller). 511 512 CONFIG_SYS_FSL_PBL_PBI 513 It enables addition of RCW (Power on reset configuration) in built image. 514 Please refer doc/README.pblimage for more details 515 516 CONFIG_SYS_FSL_PBL_RCW 517 It adds PBI(pre-boot instructions) commands in u-boot build image. 518 PBI commands can be used to configure SoC before it starts the execution. 519 Please refer doc/README.pblimage for more details 520 521 CONFIG_SPL_FSL_PBL 522 It adds a target to create boot binary having SPL binary in PBI format 523 concatenated with u-boot binary. 524 525 CONFIG_SYS_FSL_DDR_BE 526 Defines the DDR controller register space as Big Endian 527 528 CONFIG_SYS_FSL_DDR_LE 529 Defines the DDR controller register space as Little Endian 530 531 CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY 532 Physical address from the view of DDR controllers. It is the 533 same as CONFIG_SYS_DDR_SDRAM_BASE for all Power SoCs. But 534 it could be different for ARM SoCs. 535 536 CONFIG_SYS_FSL_DDR_INTLV_256B 537 DDR controller interleaving on 256-byte. This is a special 538 interleaving mode, handled by Dickens for Freescale layerscape 539 SoCs with ARM core. 540 541 CONFIG_SYS_FSL_DDR_MAIN_NUM_CTRLS 542 Number of controllers used as main memory. 543 544 CONFIG_SYS_FSL_OTHER_DDR_NUM_CTRLS 545 Number of controllers used for other than main memory. 546 547 CONFIG_SYS_FSL_HAS_DP_DDR 548 Defines the SoC has DP-DDR used for DPAA. 549 550 CONFIG_SYS_FSL_SEC_BE 551 Defines the SEC controller register space as Big Endian 552 553 CONFIG_SYS_FSL_SEC_LE 554 Defines the SEC controller register space as Little Endian 555 556- MIPS CPU options: 557 CONFIG_SYS_INIT_SP_OFFSET 558 559 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack 560 pointer. This is needed for the temporary stack before 561 relocation. 562 563 CONFIG_SYS_MIPS_CACHE_MODE 564 565 Cache operation mode for the MIPS CPU. 566 See also arch/mips/include/asm/mipsregs.h. 567 Possible values are: 568 CONF_CM_CACHABLE_NO_WA 569 CONF_CM_CACHABLE_WA 570 CONF_CM_UNCACHED 571 CONF_CM_CACHABLE_NONCOHERENT 572 CONF_CM_CACHABLE_CE 573 CONF_CM_CACHABLE_COW 574 CONF_CM_CACHABLE_CUW 575 CONF_CM_CACHABLE_ACCELERATED 576 577 CONFIG_SYS_XWAY_EBU_BOOTCFG 578 579 Special option for Lantiq XWAY SoCs for booting from NOR flash. 580 See also arch/mips/cpu/mips32/start.S. 581 582 CONFIG_XWAY_SWAP_BYTES 583 584 Enable compilation of tools/xway-swap-bytes needed for Lantiq 585 XWAY SoCs for booting from NOR flash. The U-Boot image needs to 586 be swapped if a flash programmer is used. 587 588- ARM options: 589 CONFIG_SYS_EXCEPTION_VECTORS_HIGH 590 591 Select high exception vectors of the ARM core, e.g., do not 592 clear the V bit of the c1 register of CP15. 593 594 COUNTER_FREQUENCY 595 Generic timer clock source frequency. 596 597 COUNTER_FREQUENCY_REAL 598 Generic timer clock source frequency if the real clock is 599 different from COUNTER_FREQUENCY, and can only be determined 600 at run time. 601 602- Tegra SoC options: 603 CONFIG_TEGRA_SUPPORT_NON_SECURE 604 605 Support executing U-Boot in non-secure (NS) mode. Certain 606 impossible actions will be skipped if the CPU is in NS mode, 607 such as ARM architectural timer initialization. 608 609- Linux Kernel Interface: 610 CONFIG_CLOCKS_IN_MHZ 611 612 U-Boot stores all clock information in Hz 613 internally. For binary compatibility with older Linux 614 kernels (which expect the clocks passed in the 615 bd_info data to be in MHz) the environment variable 616 "clocks_in_mhz" can be defined so that U-Boot 617 converts clock data to MHZ before passing it to the 618 Linux kernel. 619 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of 620 "clocks_in_mhz=1" is automatically included in the 621 default environment. 622 623 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only] 624 625 When transferring memsize parameter to Linux, some versions 626 expect it to be in bytes, others in MB. 627 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes. 628 629 CONFIG_OF_LIBFDT 630 631 New kernel versions are expecting firmware settings to be 632 passed using flattened device trees (based on open firmware 633 concepts). 634 635 CONFIG_OF_LIBFDT 636 * New libfdt-based support 637 * Adds the "fdt" command 638 * The bootm command automatically updates the fdt 639 640 OF_CPU - The proper name of the cpus node (only required for 641 MPC512X and MPC5xxx based boards). 642 OF_SOC - The proper name of the soc node (only required for 643 MPC512X and MPC5xxx based boards). 644 OF_TBCLK - The timebase frequency. 645 OF_STDOUT_PATH - The path to the console device 646 647 boards with QUICC Engines require OF_QE to set UCC MAC 648 addresses 649 650 CONFIG_OF_BOARD_SETUP 651 652 Board code has addition modification that it wants to make 653 to the flat device tree before handing it off to the kernel 654 655 CONFIG_OF_SYSTEM_SETUP 656 657 Other code has addition modification that it wants to make 658 to the flat device tree before handing it off to the kernel. 659 This causes ft_system_setup() to be called before booting 660 the kernel. 661 662 CONFIG_OF_IDE_FIXUP 663 664 U-Boot can detect if an IDE device is present or not. 665 If not, and this new config option is activated, U-Boot 666 removes the ATA node from the DTS before booting Linux, 667 so the Linux IDE driver does not probe the device and 668 crash. This is needed for buggy hardware (uc101) where 669 no pull down resistor is connected to the signal IDE5V_DD7. 670 671 CONFIG_MACH_TYPE [relevant for ARM only][mandatory] 672 673 This setting is mandatory for all boards that have only one 674 machine type and must be used to specify the machine type 675 number as it appears in the ARM machine registry 676 (see http://www.arm.linux.org.uk/developer/machines/). 677 Only boards that have multiple machine types supported 678 in a single configuration file and the machine type is 679 runtime discoverable, do not have to use this setting. 680 681- vxWorks boot parameters: 682 683 bootvx constructs a valid bootline using the following 684 environments variables: bootdev, bootfile, ipaddr, netmask, 685 serverip, gatewayip, hostname, othbootargs. 686 It loads the vxWorks image pointed bootfile. 687 688 Note: If a "bootargs" environment is defined, it will overwride 689 the defaults discussed just above. 690 691- Cache Configuration: 692 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot 693 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot 694 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot 695 696- Cache Configuration for ARM: 697 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache 698 controller 699 CONFIG_SYS_PL310_BASE - Physical base address of PL310 700 controller register space 701 702- Serial Ports: 703 CONFIG_PL010_SERIAL 704 705 Define this if you want support for Amba PrimeCell PL010 UARTs. 706 707 CONFIG_PL011_SERIAL 708 709 Define this if you want support for Amba PrimeCell PL011 UARTs. 710 711 CONFIG_PL011_CLOCK 712 713 If you have Amba PrimeCell PL011 UARTs, set this variable to 714 the clock speed of the UARTs. 715 716 CONFIG_PL01x_PORTS 717 718 If you have Amba PrimeCell PL010 or PL011 UARTs on your board, 719 define this to a list of base addresses for each (supported) 720 port. See e.g. include/configs/versatile.h 721 722 CONFIG_SERIAL_HW_FLOW_CONTROL 723 724 Define this variable to enable hw flow control in serial driver. 725 Current user of this option is drivers/serial/nsl16550.c driver 726 727- Console Interface: 728 Depending on board, define exactly one serial port 729 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2, 730 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial 731 console by defining CONFIG_8xx_CONS_NONE 732 733 Note: if CONFIG_8xx_CONS_NONE is defined, the serial 734 port routines must be defined elsewhere 735 (i.e. serial_init(), serial_getc(), ...) 736 737- Console Baudrate: 738 CONFIG_BAUDRATE - in bps 739 Select one of the baudrates listed in 740 CONFIG_SYS_BAUDRATE_TABLE, see below. 741 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale 742 743- Console Rx buffer length 744 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define 745 the maximum receive buffer length for the SMC. 746 This option is actual only for 82xx and 8xx possible. 747 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE 748 must be defined, to setup the maximum idle timeout for 749 the SMC. 750 751- Autoboot Command: 752 CONFIG_BOOTCOMMAND 753 Only needed when CONFIG_BOOTDELAY is enabled; 754 define a command string that is automatically executed 755 when no character is read on the console interface 756 within "Boot Delay" after reset. 757 758 CONFIG_BOOTARGS 759 This can be used to pass arguments to the bootm 760 command. The value of CONFIG_BOOTARGS goes into the 761 environment value "bootargs". 762 763 CONFIG_RAMBOOT and CONFIG_NFSBOOT 764 The value of these goes into the environment as 765 "ramboot" and "nfsboot" respectively, and can be used 766 as a convenience, when switching between booting from 767 RAM and NFS. 768 769- Bootcount: 770 CONFIG_BOOTCOUNT_LIMIT 771 Implements a mechanism for detecting a repeating reboot 772 cycle, see: 773 http://www.denx.de/wiki/view/DULG/UBootBootCountLimit 774 775 CONFIG_BOOTCOUNT_ENV 776 If no softreset save registers are found on the hardware 777 "bootcount" is stored in the environment. To prevent a 778 saveenv on all reboots, the environment variable 779 "upgrade_available" is used. If "upgrade_available" is 780 0, "bootcount" is always 0, if "upgrade_available" is 781 1 "bootcount" is incremented in the environment. 782 So the Userspace Applikation must set the "upgrade_available" 783 and "bootcount" variable to 0, if a boot was successfully. 784 785- Pre-Boot Commands: 786 CONFIG_PREBOOT 787 788 When this option is #defined, the existence of the 789 environment variable "preboot" will be checked 790 immediately before starting the CONFIG_BOOTDELAY 791 countdown and/or running the auto-boot command resp. 792 entering interactive mode. 793 794 This feature is especially useful when "preboot" is 795 automatically generated or modified. For an example 796 see the LWMON board specific code: here "preboot" is 797 modified when the user holds down a certain 798 combination of keys on the (special) keyboard when 799 booting the systems 800 801- Serial Download Echo Mode: 802 CONFIG_LOADS_ECHO 803 If defined to 1, all characters received during a 804 serial download (using the "loads" command) are 805 echoed back. This might be needed by some terminal 806 emulations (like "cu"), but may as well just take 807 time on others. This setting #define's the initial 808 value of the "loads_echo" environment variable. 809 810- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined) 811 CONFIG_KGDB_BAUDRATE 812 Select one of the baudrates listed in 813 CONFIG_SYS_BAUDRATE_TABLE, see below. 814 815- Monitor Functions: 816 Monitor commands can be included or excluded 817 from the build by using the #include files 818 <config_cmd_all.h> and #undef'ing unwanted 819 commands, or adding #define's for wanted commands. 820 821 The default command configuration includes all commands 822 except those marked below with a "*". 823 824 CONFIG_CMD_AES AES 128 CBC encrypt/decrypt 825 CONFIG_CMD_ASKENV * ask for env variable 826 CONFIG_CMD_BDI bdinfo 827 CONFIG_CMD_BEDBUG * Include BedBug Debugger 828 CONFIG_CMD_BMP * BMP support 829 CONFIG_CMD_BSP * Board specific commands 830 CONFIG_CMD_BOOTD bootd 831 CONFIG_CMD_BOOTI * ARM64 Linux kernel Image support 832 CONFIG_CMD_CACHE * icache, dcache 833 CONFIG_CMD_CLK * clock command support 834 CONFIG_CMD_CONSOLE coninfo 835 CONFIG_CMD_CRC32 * crc32 836 CONFIG_CMD_DATE * support for RTC, date/time... 837 CONFIG_CMD_DHCP * DHCP support 838 CONFIG_CMD_DIAG * Diagnostics 839 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands 840 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command 841 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd 842 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command 843 CONFIG_CMD_DTT * Digital Therm and Thermostat 844 CONFIG_CMD_ECHO echo arguments 845 CONFIG_CMD_EDITENV edit env variable 846 CONFIG_CMD_EEPROM * EEPROM read/write support 847 CONFIG_CMD_EEPROM_LAYOUT* EEPROM layout aware commands 848 CONFIG_CMD_ELF * bootelf, bootvx 849 CONFIG_CMD_ENV_CALLBACK * display details about env callbacks 850 CONFIG_CMD_ENV_FLAGS * display details about env flags 851 CONFIG_CMD_ENV_EXISTS * check existence of env variable 852 CONFIG_CMD_EXPORTENV * export the environment 853 CONFIG_CMD_EXT2 * ext2 command support 854 CONFIG_CMD_EXT4 * ext4 command support 855 CONFIG_CMD_FS_GENERIC * filesystem commands (e.g. load, ls) 856 that work for multiple fs types 857 CONFIG_CMD_FS_UUID * Look up a filesystem UUID 858 CONFIG_CMD_SAVEENV saveenv 859 CONFIG_CMD_FDC * Floppy Disk Support 860 CONFIG_CMD_FAT * FAT command support 861 CONFIG_CMD_FLASH flinfo, erase, protect 862 CONFIG_CMD_FPGA FPGA device initialization support 863 CONFIG_CMD_FUSE * Device fuse support 864 CONFIG_CMD_GETTIME * Get time since boot 865 CONFIG_CMD_GO * the 'go' command (exec code) 866 CONFIG_CMD_GREPENV * search environment 867 CONFIG_CMD_HASH * calculate hash / digest 868 CONFIG_CMD_I2C * I2C serial bus support 869 CONFIG_CMD_IDE * IDE harddisk support 870 CONFIG_CMD_IMI iminfo 871 CONFIG_CMD_IMLS List all images found in NOR flash 872 CONFIG_CMD_IMLS_NAND * List all images found in NAND flash 873 CONFIG_CMD_IMMAP * IMMR dump support 874 CONFIG_CMD_IOTRACE * I/O tracing for debugging 875 CONFIG_CMD_IMPORTENV * import an environment 876 CONFIG_CMD_INI * import data from an ini file into the env 877 CONFIG_CMD_IRQ * irqinfo 878 CONFIG_CMD_ITEST Integer/string test of 2 values 879 CONFIG_CMD_JFFS2 * JFFS2 Support 880 CONFIG_CMD_KGDB * kgdb 881 CONFIG_CMD_LDRINFO * ldrinfo (display Blackfin loader) 882 CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration 883 (169.254.*.*) 884 CONFIG_CMD_LOADB loadb 885 CONFIG_CMD_LOADS loads 886 CONFIG_CMD_MD5SUM * print md5 message digest 887 (requires CONFIG_CMD_MEMORY and CONFIG_MD5) 888 CONFIG_CMD_MEMINFO * Display detailed memory information 889 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base, 890 loop, loopw 891 CONFIG_CMD_MEMTEST * mtest 892 CONFIG_CMD_MISC Misc functions like sleep etc 893 CONFIG_CMD_MMC * MMC memory mapped support 894 CONFIG_CMD_MII * MII utility commands 895 CONFIG_CMD_MTDPARTS * MTD partition support 896 CONFIG_CMD_NAND * NAND support 897 CONFIG_CMD_NET bootp, tftpboot, rarpboot 898 CONFIG_CMD_NFS NFS support 899 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands 900 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command 901 CONFIG_CMD_PCI * pciinfo 902 CONFIG_CMD_PCMCIA * PCMCIA support 903 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network 904 host 905 CONFIG_CMD_PORTIO * Port I/O 906 CONFIG_CMD_READ * Read raw data from partition 907 CONFIG_CMD_REGINFO * Register dump 908 CONFIG_CMD_RUN run command in env variable 909 CONFIG_CMD_SANDBOX * sb command to access sandbox features 910 CONFIG_CMD_SAVES * save S record dump 911 CONFIG_SCSI * SCSI Support 912 CONFIG_CMD_SDRAM * print SDRAM configuration information 913 (requires CONFIG_CMD_I2C) 914 CONFIG_CMD_SETGETDCR Support for DCR Register access 915 (4xx only) 916 CONFIG_CMD_SF * Read/write/erase SPI NOR flash 917 CONFIG_CMD_SHA1SUM * print sha1 memory digest 918 (requires CONFIG_CMD_MEMORY) 919 CONFIG_CMD_SOFTSWITCH * Soft switch setting command for BF60x 920 CONFIG_CMD_SOURCE "source" command Support 921 CONFIG_CMD_SPI * SPI serial bus support 922 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode 923 CONFIG_CMD_TFTPPUT * TFTP put command (upload) 924 CONFIG_CMD_TIME * run command and report execution time (ARM specific) 925 CONFIG_CMD_TIMER * access to the system tick timer 926 CONFIG_CMD_USB * USB support 927 CONFIG_CMD_CDP * Cisco Discover Protocol support 928 CONFIG_CMD_MFSL * Microblaze FSL support 929 CONFIG_CMD_XIMG Load part of Multi Image 930 CONFIG_CMD_UUID * Generate random UUID or GUID string 931 932 EXAMPLE: If you want all functions except of network 933 support you can write: 934 935 #include "config_cmd_all.h" 936 #undef CONFIG_CMD_NET 937 938 Other Commands: 939 fdt (flattened device tree) command: CONFIG_OF_LIBFDT 940 941 Note: Don't enable the "icache" and "dcache" commands 942 (configuration option CONFIG_CMD_CACHE) unless you know 943 what you (and your U-Boot users) are doing. Data 944 cache cannot be enabled on systems like the 8xx or 945 8260 (where accesses to the IMMR region must be 946 uncached), and it cannot be disabled on all other 947 systems where we (mis-) use the data cache to hold an 948 initial stack and some data. 949 950 951 XXX - this list needs to get updated! 952 953- Removal of commands 954 If no commands are needed to boot, you can disable 955 CONFIG_CMDLINE to remove them. In this case, the command line 956 will not be available, and when U-Boot wants to execute the 957 boot command (on start-up) it will call board_run_command() 958 instead. This can reduce image size significantly for very 959 simple boot procedures. 960 961- Regular expression support: 962 CONFIG_REGEX 963 If this variable is defined, U-Boot is linked against 964 the SLRE (Super Light Regular Expression) library, 965 which adds regex support to some commands, as for 966 example "env grep" and "setexpr". 967 968- Device tree: 969 CONFIG_OF_CONTROL 970 If this variable is defined, U-Boot will use a device tree 971 to configure its devices, instead of relying on statically 972 compiled #defines in the board file. This option is 973 experimental and only available on a few boards. The device 974 tree is available in the global data as gd->fdt_blob. 975 976 U-Boot needs to get its device tree from somewhere. This can 977 be done using one of the two options below: 978 979 CONFIG_OF_EMBED 980 If this variable is defined, U-Boot will embed a device tree 981 binary in its image. This device tree file should be in the 982 board directory and called <soc>-<board>.dts. The binary file 983 is then picked up in board_init_f() and made available through 984 the global data structure as gd->blob. 985 986 CONFIG_OF_SEPARATE 987 If this variable is defined, U-Boot will build a device tree 988 binary. It will be called u-boot.dtb. Architecture-specific 989 code will locate it at run-time. Generally this works by: 990 991 cat u-boot.bin u-boot.dtb >image.bin 992 993 and in fact, U-Boot does this for you, creating a file called 994 u-boot-dtb.bin which is useful in the common case. You can 995 still use the individual files if you need something more 996 exotic. 997 998- Watchdog: 999 CONFIG_WATCHDOG 1000 If this variable is defined, it enables watchdog 1001 support for the SoC. There must be support in the SoC 1002 specific code for a watchdog. For the 8xx and 8260 1003 CPUs, the SIU Watchdog feature is enabled in the SYPCR 1004 register. When supported for a specific SoC is 1005 available, then no further board specific code should 1006 be needed to use it. 1007 1008 CONFIG_HW_WATCHDOG 1009 When using a watchdog circuitry external to the used 1010 SoC, then define this variable and provide board 1011 specific code for the "hw_watchdog_reset" function. 1012 1013 CONFIG_AT91_HW_WDT_TIMEOUT 1014 specify the timeout in seconds. default 2 seconds. 1015 1016- U-Boot Version: 1017 CONFIG_VERSION_VARIABLE 1018 If this variable is defined, an environment variable 1019 named "ver" is created by U-Boot showing the U-Boot 1020 version as printed by the "version" command. 1021 Any change to this variable will be reverted at the 1022 next reset. 1023 1024- Real-Time Clock: 1025 1026 When CONFIG_CMD_DATE is selected, the type of the RTC 1027 has to be selected, too. Define exactly one of the 1028 following options: 1029 1030 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx 1031 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC 1032 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC 1033 CONFIG_RTC_MC146818 - use MC146818 RTC 1034 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC 1035 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC 1036 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC 1037 CONFIG_RTC_DS1339 - use Maxim, Inc. DS1339 RTC 1038 CONFIG_RTC_DS164x - use Dallas DS164x RTC 1039 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC 1040 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC 1041 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337 1042 CONFIG_SYS_RV3029_TCR - enable trickle charger on 1043 RV3029 RTC. 1044 1045 Note that if the RTC uses I2C, then the I2C interface 1046 must also be configured. See I2C Support, below. 1047 1048- GPIO Support: 1049 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO 1050 1051 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of 1052 chip-ngpio pairs that tell the PCA953X driver the number of 1053 pins supported by a particular chip. 1054 1055 Note that if the GPIO device uses I2C, then the I2C interface 1056 must also be configured. See I2C Support, below. 1057 1058- I/O tracing: 1059 When CONFIG_IO_TRACE is selected, U-Boot intercepts all I/O 1060 accesses and can checksum them or write a list of them out 1061 to memory. See the 'iotrace' command for details. This is 1062 useful for testing device drivers since it can confirm that 1063 the driver behaves the same way before and after a code 1064 change. Currently this is supported on sandbox and arm. To 1065 add support for your architecture, add '#include <iotrace.h>' 1066 to the bottom of arch/<arch>/include/asm/io.h and test. 1067 1068 Example output from the 'iotrace stats' command is below. 1069 Note that if the trace buffer is exhausted, the checksum will 1070 still continue to operate. 1071 1072 iotrace is enabled 1073 Start: 10000000 (buffer start address) 1074 Size: 00010000 (buffer size) 1075 Offset: 00000120 (current buffer offset) 1076 Output: 10000120 (start + offset) 1077 Count: 00000018 (number of trace records) 1078 CRC32: 9526fb66 (CRC32 of all trace records) 1079 1080- Timestamp Support: 1081 1082 When CONFIG_TIMESTAMP is selected, the timestamp 1083 (date and time) of an image is printed by image 1084 commands like bootm or iminfo. This option is 1085 automatically enabled when you select CONFIG_CMD_DATE . 1086 1087- Partition Labels (disklabels) Supported: 1088 Zero or more of the following: 1089 CONFIG_MAC_PARTITION Apple's MacOS partition table. 1090 CONFIG_DOS_PARTITION MS Dos partition table, traditional on the 1091 Intel architecture, USB sticks, etc. 1092 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc. 1093 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the 1094 bootloader. Note 2TB partition limit; see 1095 disk/part_efi.c 1096 CONFIG_MTD_PARTITIONS Memory Technology Device partition table. 1097 1098 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or 1099 CONFIG_SCSI) you must configure support for at 1100 least one non-MTD partition type as well. 1101 1102- IDE Reset method: 1103 CONFIG_IDE_RESET_ROUTINE - this is defined in several 1104 board configurations files but used nowhere! 1105 1106 CONFIG_IDE_RESET - is this is defined, IDE Reset will 1107 be performed by calling the function 1108 ide_set_reset(int reset) 1109 which has to be defined in a board specific file 1110 1111- ATAPI Support: 1112 CONFIG_ATAPI 1113 1114 Set this to enable ATAPI support. 1115 1116- LBA48 Support 1117 CONFIG_LBA48 1118 1119 Set this to enable support for disks larger than 137GB 1120 Also look at CONFIG_SYS_64BIT_LBA. 1121 Whithout these , LBA48 support uses 32bit variables and will 'only' 1122 support disks up to 2.1TB. 1123 1124 CONFIG_SYS_64BIT_LBA: 1125 When enabled, makes the IDE subsystem use 64bit sector addresses. 1126 Default is 32bit. 1127 1128- SCSI Support: 1129 At the moment only there is only support for the 1130 SYM53C8XX SCSI controller; define 1131 CONFIG_SCSI_SYM53C8XX to enable it. 1132 1133 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and 1134 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID * 1135 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the 1136 maximum numbers of LUNs, SCSI ID's and target 1137 devices. 1138 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz) 1139 1140 The environment variable 'scsidevs' is set to the number of 1141 SCSI devices found during the last scan. 1142 1143- NETWORK Support (PCI): 1144 CONFIG_E1000 1145 Support for Intel 8254x/8257x gigabit chips. 1146 1147 CONFIG_E1000_SPI 1148 Utility code for direct access to the SPI bus on Intel 8257x. 1149 This does not do anything useful unless you set at least one 1150 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC. 1151 1152 CONFIG_E1000_SPI_GENERIC 1153 Allow generic access to the SPI bus on the Intel 8257x, for 1154 example with the "sspi" command. 1155 1156 CONFIG_CMD_E1000 1157 Management command for E1000 devices. When used on devices 1158 with SPI support you can reprogram the EEPROM from U-Boot. 1159 1160 CONFIG_EEPRO100 1161 Support for Intel 82557/82559/82559ER chips. 1162 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM 1163 write routine for first time initialisation. 1164 1165 CONFIG_TULIP 1166 Support for Digital 2114x chips. 1167 Optional CONFIG_TULIP_SELECT_MEDIA for board specific 1168 modem chip initialisation (KS8761/QS6611). 1169 1170 CONFIG_NATSEMI 1171 Support for National dp83815 chips. 1172 1173 CONFIG_NS8382X 1174 Support for National dp8382[01] gigabit chips. 1175 1176- NETWORK Support (other): 1177 1178 CONFIG_DRIVER_AT91EMAC 1179 Support for AT91RM9200 EMAC. 1180 1181 CONFIG_RMII 1182 Define this to use reduced MII inteface 1183 1184 CONFIG_DRIVER_AT91EMAC_QUIET 1185 If this defined, the driver is quiet. 1186 The driver doen't show link status messages. 1187 1188 CONFIG_CALXEDA_XGMAC 1189 Support for the Calxeda XGMAC device 1190 1191 CONFIG_LAN91C96 1192 Support for SMSC's LAN91C96 chips. 1193 1194 CONFIG_LAN91C96_USE_32_BIT 1195 Define this to enable 32 bit addressing 1196 1197 CONFIG_SMC91111 1198 Support for SMSC's LAN91C111 chip 1199 1200 CONFIG_SMC91111_BASE 1201 Define this to hold the physical address 1202 of the device (I/O space) 1203 1204 CONFIG_SMC_USE_32_BIT 1205 Define this if data bus is 32 bits 1206 1207 CONFIG_SMC_USE_IOFUNCS 1208 Define this to use i/o functions instead of macros 1209 (some hardware wont work with macros) 1210 1211 CONFIG_DRIVER_TI_EMAC 1212 Support for davinci emac 1213 1214 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT 1215 Define this if you have more then 3 PHYs. 1216 1217 CONFIG_FTGMAC100 1218 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet 1219 1220 CONFIG_FTGMAC100_EGIGA 1221 Define this to use GE link update with gigabit PHY. 1222 Define this if FTGMAC100 is connected to gigabit PHY. 1223 If your system has 10/100 PHY only, it might not occur 1224 wrong behavior. Because PHY usually return timeout or 1225 useless data when polling gigabit status and gigabit 1226 control registers. This behavior won't affect the 1227 correctnessof 10/100 link speed update. 1228 1229 CONFIG_SMC911X 1230 Support for SMSC's LAN911x and LAN921x chips 1231 1232 CONFIG_SMC911X_BASE 1233 Define this to hold the physical address 1234 of the device (I/O space) 1235 1236 CONFIG_SMC911X_32_BIT 1237 Define this if data bus is 32 bits 1238 1239 CONFIG_SMC911X_16_BIT 1240 Define this if data bus is 16 bits. If your processor 1241 automatically converts one 32 bit word to two 16 bit 1242 words you may also try CONFIG_SMC911X_32_BIT. 1243 1244 CONFIG_SH_ETHER 1245 Support for Renesas on-chip Ethernet controller 1246 1247 CONFIG_SH_ETHER_USE_PORT 1248 Define the number of ports to be used 1249 1250 CONFIG_SH_ETHER_PHY_ADDR 1251 Define the ETH PHY's address 1252 1253 CONFIG_SH_ETHER_CACHE_WRITEBACK 1254 If this option is set, the driver enables cache flush. 1255 1256- PWM Support: 1257 CONFIG_PWM_IMX 1258 Support for PWM module on the imx6. 1259 1260- TPM Support: 1261 CONFIG_TPM 1262 Support TPM devices. 1263 1264 CONFIG_TPM_TIS_INFINEON 1265 Support for Infineon i2c bus TPM devices. Only one device 1266 per system is supported at this time. 1267 1268 CONFIG_TPM_TIS_I2C_BURST_LIMITATION 1269 Define the burst count bytes upper limit 1270 1271 CONFIG_TPM_ST33ZP24 1272 Support for STMicroelectronics TPM devices. Requires DM_TPM support. 1273 1274 CONFIG_TPM_ST33ZP24_I2C 1275 Support for STMicroelectronics ST33ZP24 I2C devices. 1276 Requires TPM_ST33ZP24 and I2C. 1277 1278 CONFIG_TPM_ST33ZP24_SPI 1279 Support for STMicroelectronics ST33ZP24 SPI devices. 1280 Requires TPM_ST33ZP24 and SPI. 1281 1282 CONFIG_TPM_ATMEL_TWI 1283 Support for Atmel TWI TPM device. Requires I2C support. 1284 1285 CONFIG_TPM_TIS_LPC 1286 Support for generic parallel port TPM devices. Only one device 1287 per system is supported at this time. 1288 1289 CONFIG_TPM_TIS_BASE_ADDRESS 1290 Base address where the generic TPM device is mapped 1291 to. Contemporary x86 systems usually map it at 1292 0xfed40000. 1293 1294 CONFIG_CMD_TPM 1295 Add tpm monitor functions. 1296 Requires CONFIG_TPM. If CONFIG_TPM_AUTH_SESSIONS is set, also 1297 provides monitor access to authorized functions. 1298 1299 CONFIG_TPM 1300 Define this to enable the TPM support library which provides 1301 functional interfaces to some TPM commands. 1302 Requires support for a TPM device. 1303 1304 CONFIG_TPM_AUTH_SESSIONS 1305 Define this to enable authorized functions in the TPM library. 1306 Requires CONFIG_TPM and CONFIG_SHA1. 1307 1308- USB Support: 1309 At the moment only the UHCI host controller is 1310 supported (PIP405, MIP405, MPC5200); define 1311 CONFIG_USB_UHCI to enable it. 1312 define CONFIG_USB_KEYBOARD to enable the USB Keyboard 1313 and define CONFIG_USB_STORAGE to enable the USB 1314 storage devices. 1315 Note: 1316 Supported are USB Keyboards and USB Floppy drives 1317 (TEAC FD-05PUB). 1318 MPC5200 USB requires additional defines: 1319 CONFIG_USB_CLOCK 1320 for 528 MHz Clock: 0x0001bbbb 1321 CONFIG_PSC3_USB 1322 for USB on PSC3 1323 CONFIG_USB_CONFIG 1324 for differential drivers: 0x00001000 1325 for single ended drivers: 0x00005000 1326 for differential drivers on PSC3: 0x00000100 1327 for single ended drivers on PSC3: 0x00004100 1328 CONFIG_SYS_USB_EVENT_POLL 1329 May be defined to allow interrupt polling 1330 instead of using asynchronous interrupts 1331 1332 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the 1333 txfilltuning field in the EHCI controller on reset. 1334 1335 CONFIG_USB_DWC2_REG_ADDR the physical CPU address of the DWC2 1336 HW module registers. 1337 1338- USB Device: 1339 Define the below if you wish to use the USB console. 1340 Once firmware is rebuilt from a serial console issue the 1341 command "setenv stdin usbtty; setenv stdout usbtty" and 1342 attach your USB cable. The Unix command "dmesg" should print 1343 it has found a new device. The environment variable usbtty 1344 can be set to gserial or cdc_acm to enable your device to 1345 appear to a USB host as a Linux gserial device or a 1346 Common Device Class Abstract Control Model serial device. 1347 If you select usbtty = gserial you should be able to enumerate 1348 a Linux host by 1349 # modprobe usbserial vendor=0xVendorID product=0xProductID 1350 else if using cdc_acm, simply setting the environment 1351 variable usbtty to be cdc_acm should suffice. The following 1352 might be defined in YourBoardName.h 1353 1354 CONFIG_USB_DEVICE 1355 Define this to build a UDC device 1356 1357 CONFIG_USB_TTY 1358 Define this to have a tty type of device available to 1359 talk to the UDC device 1360 1361 CONFIG_USBD_HS 1362 Define this to enable the high speed support for usb 1363 device and usbtty. If this feature is enabled, a routine 1364 int is_usbd_high_speed(void) 1365 also needs to be defined by the driver to dynamically poll 1366 whether the enumeration has succeded at high speed or full 1367 speed. 1368 1369 CONFIG_SYS_CONSOLE_IS_IN_ENV 1370 Define this if you want stdin, stdout &/or stderr to 1371 be set to usbtty. 1372 1373 mpc8xx: 1374 CONFIG_SYS_USB_EXTC_CLK 0xBLAH 1375 Derive USB clock from external clock "blah" 1376 - CONFIG_SYS_USB_EXTC_CLK 0x02 1377 1378 If you have a USB-IF assigned VendorID then you may wish to 1379 define your own vendor specific values either in BoardName.h 1380 or directly in usbd_vendor_info.h. If you don't define 1381 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME, 1382 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot 1383 should pretend to be a Linux device to it's target host. 1384 1385 CONFIG_USBD_MANUFACTURER 1386 Define this string as the name of your company for 1387 - CONFIG_USBD_MANUFACTURER "my company" 1388 1389 CONFIG_USBD_PRODUCT_NAME 1390 Define this string as the name of your product 1391 - CONFIG_USBD_PRODUCT_NAME "acme usb device" 1392 1393 CONFIG_USBD_VENDORID 1394 Define this as your assigned Vendor ID from the USB 1395 Implementors Forum. This *must* be a genuine Vendor ID 1396 to avoid polluting the USB namespace. 1397 - CONFIG_USBD_VENDORID 0xFFFF 1398 1399 CONFIG_USBD_PRODUCTID 1400 Define this as the unique Product ID 1401 for your device 1402 - CONFIG_USBD_PRODUCTID 0xFFFF 1403 1404- ULPI Layer Support: 1405 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via 1406 the generic ULPI layer. The generic layer accesses the ULPI PHY 1407 via the platform viewport, so you need both the genric layer and 1408 the viewport enabled. Currently only Chipidea/ARC based 1409 viewport is supported. 1410 To enable the ULPI layer support, define CONFIG_USB_ULPI and 1411 CONFIG_USB_ULPI_VIEWPORT in your board configuration file. 1412 If your ULPI phy needs a different reference clock than the 1413 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to 1414 the appropriate value in Hz. 1415 1416- MMC Support: 1417 The MMC controller on the Intel PXA is supported. To 1418 enable this define CONFIG_MMC. The MMC can be 1419 accessed from the boot prompt by mapping the device 1420 to physical memory similar to flash. Command line is 1421 enabled with CONFIG_CMD_MMC. The MMC driver also works with 1422 the FAT fs. This is enabled with CONFIG_CMD_FAT. 1423 1424 CONFIG_SH_MMCIF 1425 Support for Renesas on-chip MMCIF controller 1426 1427 CONFIG_SH_MMCIF_ADDR 1428 Define the base address of MMCIF registers 1429 1430 CONFIG_SH_MMCIF_CLK 1431 Define the clock frequency for MMCIF 1432 1433 CONFIG_SUPPORT_EMMC_BOOT 1434 Enable some additional features of the eMMC boot partitions. 1435 1436 CONFIG_SUPPORT_EMMC_RPMB 1437 Enable the commands for reading, writing and programming the 1438 key for the Replay Protection Memory Block partition in eMMC. 1439 1440- USB Device Firmware Update (DFU) class support: 1441 CONFIG_USB_FUNCTION_DFU 1442 This enables the USB portion of the DFU USB class 1443 1444 CONFIG_CMD_DFU 1445 This enables the command "dfu" which is used to have 1446 U-Boot create a DFU class device via USB. This command 1447 requires that the "dfu_alt_info" environment variable be 1448 set and define the alt settings to expose to the host. 1449 1450 CONFIG_DFU_MMC 1451 This enables support for exposing (e)MMC devices via DFU. 1452 1453 CONFIG_DFU_NAND 1454 This enables support for exposing NAND devices via DFU. 1455 1456 CONFIG_DFU_RAM 1457 This enables support for exposing RAM via DFU. 1458 Note: DFU spec refer to non-volatile memory usage, but 1459 allow usages beyond the scope of spec - here RAM usage, 1460 one that would help mostly the developer. 1461 1462 CONFIG_SYS_DFU_DATA_BUF_SIZE 1463 Dfu transfer uses a buffer before writing data to the 1464 raw storage device. Make the size (in bytes) of this buffer 1465 configurable. The size of this buffer is also configurable 1466 through the "dfu_bufsiz" environment variable. 1467 1468 CONFIG_SYS_DFU_MAX_FILE_SIZE 1469 When updating files rather than the raw storage device, 1470 we use a static buffer to copy the file into and then write 1471 the buffer once we've been given the whole file. Define 1472 this to the maximum filesize (in bytes) for the buffer. 1473 Default is 4 MiB if undefined. 1474 1475 DFU_DEFAULT_POLL_TIMEOUT 1476 Poll timeout [ms], is the timeout a device can send to the 1477 host. The host must wait for this timeout before sending 1478 a subsequent DFU_GET_STATUS request to the device. 1479 1480 DFU_MANIFEST_POLL_TIMEOUT 1481 Poll timeout [ms], which the device sends to the host when 1482 entering dfuMANIFEST state. Host waits this timeout, before 1483 sending again an USB request to the device. 1484 1485- USB Device Android Fastboot support: 1486 CONFIG_USB_FUNCTION_FASTBOOT 1487 This enables the USB part of the fastboot gadget 1488 1489 CONFIG_CMD_FASTBOOT 1490 This enables the command "fastboot" which enables the Android 1491 fastboot mode for the platform's USB device. Fastboot is a USB 1492 protocol for downloading images, flashing and device control 1493 used on Android devices. 1494 See doc/README.android-fastboot for more information. 1495 1496 CONFIG_ANDROID_BOOT_IMAGE 1497 This enables support for booting images which use the Android 1498 image format header. 1499 1500 CONFIG_FASTBOOT_BUF_ADDR 1501 The fastboot protocol requires a large memory buffer for 1502 downloads. Define this to the starting RAM address to use for 1503 downloaded images. 1504 1505 CONFIG_FASTBOOT_BUF_SIZE 1506 The fastboot protocol requires a large memory buffer for 1507 downloads. This buffer should be as large as possible for a 1508 platform. Define this to the size available RAM for fastboot. 1509 1510 CONFIG_FASTBOOT_FLASH 1511 The fastboot protocol includes a "flash" command for writing 1512 the downloaded image to a non-volatile storage device. Define 1513 this to enable the "fastboot flash" command. 1514 1515 CONFIG_FASTBOOT_FLASH_MMC_DEV 1516 The fastboot "flash" command requires additional information 1517 regarding the non-volatile storage device. Define this to 1518 the eMMC device that fastboot should use to store the image. 1519 1520 CONFIG_FASTBOOT_GPT_NAME 1521 The fastboot "flash" command supports writing the downloaded 1522 image to the Protective MBR and the Primary GUID Partition 1523 Table. (Additionally, this downloaded image is post-processed 1524 to generate and write the Backup GUID Partition Table.) 1525 This occurs when the specified "partition name" on the 1526 "fastboot flash" command line matches this value. 1527 The default is "gpt" if undefined. 1528 1529 CONFIG_FASTBOOT_MBR_NAME 1530 The fastboot "flash" command supports writing the downloaded 1531 image to DOS MBR. 1532 This occurs when the "partition name" specified on the 1533 "fastboot flash" command line matches this value. 1534 If not defined the default value "mbr" is used. 1535 1536- Journaling Flash filesystem support: 1537 CONFIG_JFFS2_NAND 1538 Define these for a default partition on a NAND device 1539 1540 CONFIG_SYS_JFFS2_FIRST_SECTOR, 1541 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS 1542 Define these for a default partition on a NOR device 1543 1544- FAT(File Allocation Table) filesystem write function support: 1545 CONFIG_FAT_WRITE 1546 1547 Define this to enable support for saving memory data as a 1548 file in FAT formatted partition. 1549 1550 This will also enable the command "fatwrite" enabling the 1551 user to write files to FAT. 1552 1553- CBFS (Coreboot Filesystem) support: 1554 CONFIG_CMD_CBFS 1555 1556 Define this to enable support for reading from a Coreboot 1557 filesystem. Available commands are cbfsinit, cbfsinfo, cbfsls 1558 and cbfsload. 1559 1560- FAT(File Allocation Table) filesystem cluster size: 1561 CONFIG_FS_FAT_MAX_CLUSTSIZE 1562 1563 Define the max cluster size for fat operations else 1564 a default value of 65536 will be defined. 1565 1566- Keyboard Support: 1567 See Kconfig help for available keyboard drivers. 1568 1569 CONFIG_KEYBOARD 1570 1571 Define this to enable a custom keyboard support. 1572 This simply calls drv_keyboard_init() which must be 1573 defined in your board-specific files. This option is deprecated 1574 and is only used by novena. For new boards, use driver model 1575 instead. 1576 1577- Video support: 1578 CONFIG_FSL_DIU_FB 1579 Enable the Freescale DIU video driver. Reference boards for 1580 SOCs that have a DIU should define this macro to enable DIU 1581 support, and should also define these other macros: 1582 1583 CONFIG_SYS_DIU_ADDR 1584 CONFIG_VIDEO 1585 CONFIG_CMD_BMP 1586 CONFIG_CFB_CONSOLE 1587 CONFIG_VIDEO_SW_CURSOR 1588 CONFIG_VGA_AS_SINGLE_DEVICE 1589 CONFIG_VIDEO_LOGO 1590 CONFIG_VIDEO_BMP_LOGO 1591 1592 The DIU driver will look for the 'video-mode' environment 1593 variable, and if defined, enable the DIU as a console during 1594 boot. See the documentation file doc/README.video for a 1595 description of this variable. 1596 1597- LCD Support: CONFIG_LCD 1598 1599 Define this to enable LCD support (for output to LCD 1600 display); also select one of the supported displays 1601 by defining one of these: 1602 1603 CONFIG_ATMEL_LCD: 1604 1605 HITACHI TX09D70VM1CCA, 3.5", 240x320. 1606 1607 CONFIG_NEC_NL6448AC33: 1608 1609 NEC NL6448AC33-18. Active, color, single scan. 1610 1611 CONFIG_NEC_NL6448BC20 1612 1613 NEC NL6448BC20-08. 6.5", 640x480. 1614 Active, color, single scan. 1615 1616 CONFIG_NEC_NL6448BC33_54 1617 1618 NEC NL6448BC33-54. 10.4", 640x480. 1619 Active, color, single scan. 1620 1621 CONFIG_SHARP_16x9 1622 1623 Sharp 320x240. Active, color, single scan. 1624 It isn't 16x9, and I am not sure what it is. 1625 1626 CONFIG_SHARP_LQ64D341 1627 1628 Sharp LQ64D341 display, 640x480. 1629 Active, color, single scan. 1630 1631 CONFIG_HLD1045 1632 1633 HLD1045 display, 640x480. 1634 Active, color, single scan. 1635 1636 CONFIG_OPTREX_BW 1637 1638 Optrex CBL50840-2 NF-FW 99 22 M5 1639 or 1640 Hitachi LMG6912RPFC-00T 1641 or 1642 Hitachi SP14Q002 1643 1644 320x240. Black & white. 1645 1646 Normally display is black on white background; define 1647 CONFIG_SYS_WHITE_ON_BLACK to get it inverted. 1648 1649 CONFIG_LCD_ALIGNMENT 1650 1651 Normally the LCD is page-aligned (typically 4KB). If this is 1652 defined then the LCD will be aligned to this value instead. 1653 For ARM it is sometimes useful to use MMU_SECTION_SIZE 1654 here, since it is cheaper to change data cache settings on 1655 a per-section basis. 1656 1657 1658 CONFIG_LCD_ROTATION 1659 1660 Sometimes, for example if the display is mounted in portrait 1661 mode or even if it's mounted landscape but rotated by 180degree, 1662 we need to rotate our content of the display relative to the 1663 framebuffer, so that user can read the messages which are 1664 printed out. 1665 Once CONFIG_LCD_ROTATION is defined, the lcd_console will be 1666 initialized with a given rotation from "vl_rot" out of 1667 "vidinfo_t" which is provided by the board specific code. 1668 The value for vl_rot is coded as following (matching to 1669 fbcon=rotate:<n> linux-kernel commandline): 1670 0 = no rotation respectively 0 degree 1671 1 = 90 degree rotation 1672 2 = 180 degree rotation 1673 3 = 270 degree rotation 1674 1675 If CONFIG_LCD_ROTATION is not defined, the console will be 1676 initialized with 0degree rotation. 1677 1678 CONFIG_LCD_BMP_RLE8 1679 1680 Support drawing of RLE8-compressed bitmaps on the LCD. 1681 1682 CONFIG_I2C_EDID 1683 1684 Enables an 'i2c edid' command which can read EDID 1685 information over I2C from an attached LCD display. 1686 1687- Splash Screen Support: CONFIG_SPLASH_SCREEN 1688 1689 If this option is set, the environment is checked for 1690 a variable "splashimage". If found, the usual display 1691 of logo, copyright and system information on the LCD 1692 is suppressed and the BMP image at the address 1693 specified in "splashimage" is loaded instead. The 1694 console is redirected to the "nulldev", too. This 1695 allows for a "silent" boot where a splash screen is 1696 loaded very quickly after power-on. 1697 1698 CONFIG_SPLASHIMAGE_GUARD 1699 1700 If this option is set, then U-Boot will prevent the environment 1701 variable "splashimage" from being set to a problematic address 1702 (see doc/README.displaying-bmps). 1703 This option is useful for targets where, due to alignment 1704 restrictions, an improperly aligned BMP image will cause a data 1705 abort. If you think you will not have problems with unaligned 1706 accesses (for example because your toolchain prevents them) 1707 there is no need to set this option. 1708 1709 CONFIG_SPLASH_SCREEN_ALIGN 1710 1711 If this option is set the splash image can be freely positioned 1712 on the screen. Environment variable "splashpos" specifies the 1713 position as "x,y". If a positive number is given it is used as 1714 number of pixel from left/top. If a negative number is given it 1715 is used as number of pixel from right/bottom. You can also 1716 specify 'm' for centering the image. 1717 1718 Example: 1719 setenv splashpos m,m 1720 => image at center of screen 1721 1722 setenv splashpos 30,20 1723 => image at x = 30 and y = 20 1724 1725 setenv splashpos -10,m 1726 => vertically centered image 1727 at x = dspWidth - bmpWidth - 9 1728 1729- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP 1730 1731 If this option is set, additionally to standard BMP 1732 images, gzipped BMP images can be displayed via the 1733 splashscreen support or the bmp command. 1734 1735- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8 1736 1737 If this option is set, 8-bit RLE compressed BMP images 1738 can be displayed via the splashscreen support or the 1739 bmp command. 1740 1741- Compression support: 1742 CONFIG_GZIP 1743 1744 Enabled by default to support gzip compressed images. 1745 1746 CONFIG_BZIP2 1747 1748 If this option is set, support for bzip2 compressed 1749 images is included. If not, only uncompressed and gzip 1750 compressed images are supported. 1751 1752 NOTE: the bzip2 algorithm requires a lot of RAM, so 1753 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should 1754 be at least 4MB. 1755 1756 CONFIG_LZMA 1757 1758 If this option is set, support for lzma compressed 1759 images is included. 1760 1761 Note: The LZMA algorithm adds between 2 and 4KB of code and it 1762 requires an amount of dynamic memory that is given by the 1763 formula: 1764 1765 (1846 + 768 << (lc + lp)) * sizeof(uint16) 1766 1767 Where lc and lp stand for, respectively, Literal context bits 1768 and Literal pos bits. 1769 1770 This value is upper-bounded by 14MB in the worst case. Anyway, 1771 for a ~4MB large kernel image, we have lc=3 and lp=0 for a 1772 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is 1773 a very small buffer. 1774 1775 Use the lzmainfo tool to determinate the lc and lp values and 1776 then calculate the amount of needed dynamic memory (ensuring 1777 the appropriate CONFIG_SYS_MALLOC_LEN value). 1778 1779 CONFIG_LZO 1780 1781 If this option is set, support for LZO compressed images 1782 is included. 1783 1784- MII/PHY support: 1785 CONFIG_PHY_ADDR 1786 1787 The address of PHY on MII bus. 1788 1789 CONFIG_PHY_CLOCK_FREQ (ppc4xx) 1790 1791 The clock frequency of the MII bus 1792 1793 CONFIG_PHY_GIGE 1794 1795 If this option is set, support for speed/duplex 1796 detection of gigabit PHY is included. 1797 1798 CONFIG_PHY_RESET_DELAY 1799 1800 Some PHY like Intel LXT971A need extra delay after 1801 reset before any MII register access is possible. 1802 For such PHY, set this option to the usec delay 1803 required. (minimum 300usec for LXT971A) 1804 1805 CONFIG_PHY_CMD_DELAY (ppc4xx) 1806 1807 Some PHY like Intel LXT971A need extra delay after 1808 command issued before MII status register can be read 1809 1810- IP address: 1811 CONFIG_IPADDR 1812 1813 Define a default value for the IP address to use for 1814 the default Ethernet interface, in case this is not 1815 determined through e.g. bootp. 1816 (Environment variable "ipaddr") 1817 1818- Server IP address: 1819 CONFIG_SERVERIP 1820 1821 Defines a default value for the IP address of a TFTP 1822 server to contact when using the "tftboot" command. 1823 (Environment variable "serverip") 1824 1825 CONFIG_KEEP_SERVERADDR 1826 1827 Keeps the server's MAC address, in the env 'serveraddr' 1828 for passing to bootargs (like Linux's netconsole option) 1829 1830- Gateway IP address: 1831 CONFIG_GATEWAYIP 1832 1833 Defines a default value for the IP address of the 1834 default router where packets to other networks are 1835 sent to. 1836 (Environment variable "gatewayip") 1837 1838- Subnet mask: 1839 CONFIG_NETMASK 1840 1841 Defines a default value for the subnet mask (or 1842 routing prefix) which is used to determine if an IP 1843 address belongs to the local subnet or needs to be 1844 forwarded through a router. 1845 (Environment variable "netmask") 1846 1847- Multicast TFTP Mode: 1848 CONFIG_MCAST_TFTP 1849 1850 Defines whether you want to support multicast TFTP as per 1851 rfc-2090; for example to work with atftp. Lets lots of targets 1852 tftp down the same boot image concurrently. Note: the Ethernet 1853 driver in use must provide a function: mcast() to join/leave a 1854 multicast group. 1855 1856- BOOTP Recovery Mode: 1857 CONFIG_BOOTP_RANDOM_DELAY 1858 1859 If you have many targets in a network that try to 1860 boot using BOOTP, you may want to avoid that all 1861 systems send out BOOTP requests at precisely the same 1862 moment (which would happen for instance at recovery 1863 from a power failure, when all systems will try to 1864 boot, thus flooding the BOOTP server. Defining 1865 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 1866 inserted before sending out BOOTP requests. The 1867 following delays are inserted then: 1868 1869 1st BOOTP request: delay 0 ... 1 sec 1870 2nd BOOTP request: delay 0 ... 2 sec 1871 3rd BOOTP request: delay 0 ... 4 sec 1872 4th and following 1873 BOOTP requests: delay 0 ... 8 sec 1874 1875 CONFIG_BOOTP_ID_CACHE_SIZE 1876 1877 BOOTP packets are uniquely identified using a 32-bit ID. The 1878 server will copy the ID from client requests to responses and 1879 U-Boot will use this to determine if it is the destination of 1880 an incoming response. Some servers will check that addresses 1881 aren't in use before handing them out (usually using an ARP 1882 ping) and therefore take up to a few hundred milliseconds to 1883 respond. Network congestion may also influence the time it 1884 takes for a response to make it back to the client. If that 1885 time is too long, U-Boot will retransmit requests. In order 1886 to allow earlier responses to still be accepted after these 1887 retransmissions, U-Boot's BOOTP client keeps a small cache of 1888 IDs. The CONFIG_BOOTP_ID_CACHE_SIZE controls the size of this 1889 cache. The default is to keep IDs for up to four outstanding 1890 requests. Increasing this will allow U-Boot to accept offers 1891 from a BOOTP client in networks with unusually high latency. 1892 1893- DHCP Advanced Options: 1894 You can fine tune the DHCP functionality by defining 1895 CONFIG_BOOTP_* symbols: 1896 1897 CONFIG_BOOTP_SUBNETMASK 1898 CONFIG_BOOTP_GATEWAY 1899 CONFIG_BOOTP_HOSTNAME 1900 CONFIG_BOOTP_NISDOMAIN 1901 CONFIG_BOOTP_BOOTPATH 1902 CONFIG_BOOTP_BOOTFILESIZE 1903 CONFIG_BOOTP_DNS 1904 CONFIG_BOOTP_DNS2 1905 CONFIG_BOOTP_SEND_HOSTNAME 1906 CONFIG_BOOTP_NTPSERVER 1907 CONFIG_BOOTP_TIMEOFFSET 1908 CONFIG_BOOTP_VENDOREX 1909 CONFIG_BOOTP_MAY_FAIL 1910 1911 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip 1912 environment variable, not the BOOTP server. 1913 1914 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found 1915 after the configured retry count, the call will fail 1916 instead of starting over. This can be used to fail over 1917 to Link-local IP address configuration if the DHCP server 1918 is not available. 1919 1920 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS 1921 serverip from a DHCP server, it is possible that more 1922 than one DNS serverip is offered to the client. 1923 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS 1924 serverip will be stored in the additional environment 1925 variable "dnsip2". The first DNS serverip is always 1926 stored in the variable "dnsip", when CONFIG_BOOTP_DNS 1927 is defined. 1928 1929 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable 1930 to do a dynamic update of a DNS server. To do this, they 1931 need the hostname of the DHCP requester. 1932 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content 1933 of the "hostname" environment variable is passed as 1934 option 12 to the DHCP server. 1935 1936 CONFIG_BOOTP_DHCP_REQUEST_DELAY 1937 1938 A 32bit value in microseconds for a delay between 1939 receiving a "DHCP Offer" and sending the "DHCP Request". 1940 This fixes a problem with certain DHCP servers that don't 1941 respond 100% of the time to a "DHCP request". E.g. On an 1942 AT91RM9200 processor running at 180MHz, this delay needed 1943 to be *at least* 15,000 usec before a Windows Server 2003 1944 DHCP server would reply 100% of the time. I recommend at 1945 least 50,000 usec to be safe. The alternative is to hope 1946 that one of the retries will be successful but note that 1947 the DHCP timeout and retry process takes a longer than 1948 this delay. 1949 1950 - Link-local IP address negotiation: 1951 Negotiate with other link-local clients on the local network 1952 for an address that doesn't require explicit configuration. 1953 This is especially useful if a DHCP server cannot be guaranteed 1954 to exist in all environments that the device must operate. 1955 1956 See doc/README.link-local for more information. 1957 1958 - CDP Options: 1959 CONFIG_CDP_DEVICE_ID 1960 1961 The device id used in CDP trigger frames. 1962 1963 CONFIG_CDP_DEVICE_ID_PREFIX 1964 1965 A two character string which is prefixed to the MAC address 1966 of the device. 1967 1968 CONFIG_CDP_PORT_ID 1969 1970 A printf format string which contains the ascii name of 1971 the port. Normally is set to "eth%d" which sets 1972 eth0 for the first Ethernet, eth1 for the second etc. 1973 1974 CONFIG_CDP_CAPABILITIES 1975 1976 A 32bit integer which indicates the device capabilities; 1977 0x00000010 for a normal host which does not forwards. 1978 1979 CONFIG_CDP_VERSION 1980 1981 An ascii string containing the version of the software. 1982 1983 CONFIG_CDP_PLATFORM 1984 1985 An ascii string containing the name of the platform. 1986 1987 CONFIG_CDP_TRIGGER 1988 1989 A 32bit integer sent on the trigger. 1990 1991 CONFIG_CDP_POWER_CONSUMPTION 1992 1993 A 16bit integer containing the power consumption of the 1994 device in .1 of milliwatts. 1995 1996 CONFIG_CDP_APPLIANCE_VLAN_TYPE 1997 1998 A byte containing the id of the VLAN. 1999 2000- Status LED: CONFIG_LED_STATUS 2001 2002 Several configurations allow to display the current 2003 status using a LED. For instance, the LED will blink 2004 fast while running U-Boot code, stop blinking as 2005 soon as a reply to a BOOTP request was received, and 2006 start blinking slow once the Linux kernel is running 2007 (supported by a status LED driver in the Linux 2008 kernel). Defining CONFIG_LED_STATUS enables this 2009 feature in U-Boot. 2010 2011 Additional options: 2012 2013 CONFIG_LED_STATUS_GPIO 2014 The status LED can be connected to a GPIO pin. 2015 In such cases, the gpio_led driver can be used as a 2016 status LED backend implementation. Define CONFIG_LED_STATUS_GPIO 2017 to include the gpio_led driver in the U-Boot binary. 2018 2019 CONFIG_GPIO_LED_INVERTED_TABLE 2020 Some GPIO connected LEDs may have inverted polarity in which 2021 case the GPIO high value corresponds to LED off state and 2022 GPIO low value corresponds to LED on state. 2023 In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined 2024 with a list of GPIO LEDs that have inverted polarity. 2025 2026- CAN Support: CONFIG_CAN_DRIVER 2027 2028 Defining CONFIG_CAN_DRIVER enables CAN driver support 2029 on those systems that support this (optional) 2030 feature, like the TQM8xxL modules. 2031 2032- I2C Support: CONFIG_SYS_I2C 2033 2034 This enable the NEW i2c subsystem, and will allow you to use 2035 i2c commands at the u-boot command line (as long as you set 2036 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c 2037 based realtime clock chips or other i2c devices. See 2038 common/cmd_i2c.c for a description of the command line 2039 interface. 2040 2041 ported i2c driver to the new framework: 2042 - drivers/i2c/soft_i2c.c: 2043 - activate first bus with CONFIG_SYS_I2C_SOFT define 2044 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE 2045 for defining speed and slave address 2046 - activate second bus with I2C_SOFT_DECLARATIONS2 define 2047 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2 2048 for defining speed and slave address 2049 - activate third bus with I2C_SOFT_DECLARATIONS3 define 2050 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3 2051 for defining speed and slave address 2052 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define 2053 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4 2054 for defining speed and slave address 2055 2056 - drivers/i2c/fsl_i2c.c: 2057 - activate i2c driver with CONFIG_SYS_I2C_FSL 2058 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register 2059 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and 2060 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first 2061 bus. 2062 - If your board supports a second fsl i2c bus, define 2063 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset 2064 CONFIG_SYS_FSL_I2C2_SPEED for the speed and 2065 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the 2066 second bus. 2067 2068 - drivers/i2c/tegra_i2c.c: 2069 - activate this driver with CONFIG_SYS_I2C_TEGRA 2070 - This driver adds 4 i2c buses with a fix speed from 2071 100000 and the slave addr 0! 2072 2073 - drivers/i2c/ppc4xx_i2c.c 2074 - activate this driver with CONFIG_SYS_I2C_PPC4XX 2075 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0 2076 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1 2077 2078 - drivers/i2c/i2c_mxc.c 2079 - activate this driver with CONFIG_SYS_I2C_MXC 2080 - enable bus 1 with CONFIG_SYS_I2C_MXC_I2C1 2081 - enable bus 2 with CONFIG_SYS_I2C_MXC_I2C2 2082 - enable bus 3 with CONFIG_SYS_I2C_MXC_I2C3 2083 - enable bus 4 with CONFIG_SYS_I2C_MXC_I2C4 2084 - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED 2085 - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE 2086 - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED 2087 - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE 2088 - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED 2089 - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE 2090 - define speed for bus 4 with CONFIG_SYS_MXC_I2C4_SPEED 2091 - define slave for bus 4 with CONFIG_SYS_MXC_I2C4_SLAVE 2092 If those defines are not set, default value is 100000 2093 for speed, and 0 for slave. 2094 2095 - drivers/i2c/rcar_i2c.c: 2096 - activate this driver with CONFIG_SYS_I2C_RCAR 2097 - This driver adds 4 i2c buses 2098 2099 - CONFIG_SYS_RCAR_I2C0_BASE for setting the register channel 0 2100 - CONFIG_SYS_RCAR_I2C0_SPEED for for the speed channel 0 2101 - CONFIG_SYS_RCAR_I2C1_BASE for setting the register channel 1 2102 - CONFIG_SYS_RCAR_I2C1_SPEED for for the speed channel 1 2103 - CONFIG_SYS_RCAR_I2C2_BASE for setting the register channel 2 2104 - CONFIG_SYS_RCAR_I2C2_SPEED for for the speed channel 2 2105 - CONFIG_SYS_RCAR_I2C3_BASE for setting the register channel 3 2106 - CONFIG_SYS_RCAR_I2C3_SPEED for for the speed channel 3 2107 - CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS for number of i2c buses 2108 2109 - drivers/i2c/sh_i2c.c: 2110 - activate this driver with CONFIG_SYS_I2C_SH 2111 - This driver adds from 2 to 5 i2c buses 2112 2113 - CONFIG_SYS_I2C_SH_BASE0 for setting the register channel 0 2114 - CONFIG_SYS_I2C_SH_SPEED0 for for the speed channel 0 2115 - CONFIG_SYS_I2C_SH_BASE1 for setting the register channel 1 2116 - CONFIG_SYS_I2C_SH_SPEED1 for for the speed channel 1 2117 - CONFIG_SYS_I2C_SH_BASE2 for setting the register channel 2 2118 - CONFIG_SYS_I2C_SH_SPEED2 for for the speed channel 2 2119 - CONFIG_SYS_I2C_SH_BASE3 for setting the register channel 3 2120 - CONFIG_SYS_I2C_SH_SPEED3 for for the speed channel 3 2121 - CONFIG_SYS_I2C_SH_BASE4 for setting the register channel 4 2122 - CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4 2123 - CONFIG_SYS_I2C_SH_NUM_CONTROLLERS for number of i2c buses 2124 2125 - drivers/i2c/omap24xx_i2c.c 2126 - activate this driver with CONFIG_SYS_I2C_OMAP24XX 2127 - CONFIG_SYS_OMAP24_I2C_SPEED speed channel 0 2128 - CONFIG_SYS_OMAP24_I2C_SLAVE slave addr channel 0 2129 - CONFIG_SYS_OMAP24_I2C_SPEED1 speed channel 1 2130 - CONFIG_SYS_OMAP24_I2C_SLAVE1 slave addr channel 1 2131 - CONFIG_SYS_OMAP24_I2C_SPEED2 speed channel 2 2132 - CONFIG_SYS_OMAP24_I2C_SLAVE2 slave addr channel 2 2133 - CONFIG_SYS_OMAP24_I2C_SPEED3 speed channel 3 2134 - CONFIG_SYS_OMAP24_I2C_SLAVE3 slave addr channel 3 2135 - CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4 2136 - CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4 2137 2138 - drivers/i2c/zynq_i2c.c 2139 - activate this driver with CONFIG_SYS_I2C_ZYNQ 2140 - set CONFIG_SYS_I2C_ZYNQ_SPEED for speed setting 2141 - set CONFIG_SYS_I2C_ZYNQ_SLAVE for slave addr 2142 2143 - drivers/i2c/s3c24x0_i2c.c: 2144 - activate this driver with CONFIG_SYS_I2C_S3C24X0 2145 - This driver adds i2c buses (11 for Exynos5250, Exynos5420 2146 9 i2c buses for Exynos4 and 1 for S3C24X0 SoCs from Samsung) 2147 with a fix speed from 100000 and the slave addr 0! 2148 2149 - drivers/i2c/ihs_i2c.c 2150 - activate this driver with CONFIG_SYS_I2C_IHS 2151 - CONFIG_SYS_I2C_IHS_CH0 activate hardware channel 0 2152 - CONFIG_SYS_I2C_IHS_SPEED_0 speed channel 0 2153 - CONFIG_SYS_I2C_IHS_SLAVE_0 slave addr channel 0 2154 - CONFIG_SYS_I2C_IHS_CH1 activate hardware channel 1 2155 - CONFIG_SYS_I2C_IHS_SPEED_1 speed channel 1 2156 - CONFIG_SYS_I2C_IHS_SLAVE_1 slave addr channel 1 2157 - CONFIG_SYS_I2C_IHS_CH2 activate hardware channel 2 2158 - CONFIG_SYS_I2C_IHS_SPEED_2 speed channel 2 2159 - CONFIG_SYS_I2C_IHS_SLAVE_2 slave addr channel 2 2160 - CONFIG_SYS_I2C_IHS_CH3 activate hardware channel 3 2161 - CONFIG_SYS_I2C_IHS_SPEED_3 speed channel 3 2162 - CONFIG_SYS_I2C_IHS_SLAVE_3 slave addr channel 3 2163 - activate dual channel with CONFIG_SYS_I2C_IHS_DUAL 2164 - CONFIG_SYS_I2C_IHS_SPEED_0_1 speed channel 0_1 2165 - CONFIG_SYS_I2C_IHS_SLAVE_0_1 slave addr channel 0_1 2166 - CONFIG_SYS_I2C_IHS_SPEED_1_1 speed channel 1_1 2167 - CONFIG_SYS_I2C_IHS_SLAVE_1_1 slave addr channel 1_1 2168 - CONFIG_SYS_I2C_IHS_SPEED_2_1 speed channel 2_1 2169 - CONFIG_SYS_I2C_IHS_SLAVE_2_1 slave addr channel 2_1 2170 - CONFIG_SYS_I2C_IHS_SPEED_3_1 speed channel 3_1 2171 - CONFIG_SYS_I2C_IHS_SLAVE_3_1 slave addr channel 3_1 2172 2173 additional defines: 2174 2175 CONFIG_SYS_NUM_I2C_BUSES 2176 Hold the number of i2c buses you want to use. 2177 2178 CONFIG_SYS_I2C_DIRECT_BUS 2179 define this, if you don't use i2c muxes on your hardware. 2180 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can 2181 omit this define. 2182 2183 CONFIG_SYS_I2C_MAX_HOPS 2184 define how many muxes are maximal consecutively connected 2185 on one i2c bus. If you not use i2c muxes, omit this 2186 define. 2187 2188 CONFIG_SYS_I2C_BUSES 2189 hold a list of buses you want to use, only used if 2190 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example 2191 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and 2192 CONFIG_SYS_NUM_I2C_BUSES = 9: 2193 2194 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \ 2195 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \ 2196 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \ 2197 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \ 2198 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \ 2199 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \ 2200 {1, {I2C_NULL_HOP}}, \ 2201 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \ 2202 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \ 2203 } 2204 2205 which defines 2206 bus 0 on adapter 0 without a mux 2207 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1 2208 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2 2209 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3 2210 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4 2211 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5 2212 bus 6 on adapter 1 without a mux 2213 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1 2214 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2 2215 2216 If you do not have i2c muxes on your board, omit this define. 2217 2218- Legacy I2C Support: CONFIG_HARD_I2C 2219 2220 NOTE: It is intended to move drivers to CONFIG_SYS_I2C which 2221 provides the following compelling advantages: 2222 2223 - more than one i2c adapter is usable 2224 - approved multibus support 2225 - better i2c mux support 2226 2227 ** Please consider updating your I2C driver now. ** 2228 2229 These enable legacy I2C serial bus commands. Defining 2230 CONFIG_HARD_I2C will include the appropriate I2C driver 2231 for the selected CPU. 2232 2233 This will allow you to use i2c commands at the u-boot 2234 command line (as long as you set CONFIG_CMD_I2C in 2235 CONFIG_COMMANDS) and communicate with i2c based realtime 2236 clock chips. See common/cmd_i2c.c for a description of the 2237 command line interface. 2238 2239 CONFIG_HARD_I2C selects a hardware I2C controller. 2240 2241 There are several other quantities that must also be 2242 defined when you define CONFIG_HARD_I2C. 2243 2244 In both cases you will need to define CONFIG_SYS_I2C_SPEED 2245 to be the frequency (in Hz) at which you wish your i2c bus 2246 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie 2247 the CPU's i2c node address). 2248 2249 Now, the u-boot i2c code for the mpc8xx 2250 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node 2251 and so its address should therefore be cleared to 0 (See, 2252 eg, MPC823e User's Manual p.16-473). So, set 2253 CONFIG_SYS_I2C_SLAVE to 0. 2254 2255 CONFIG_SYS_I2C_INIT_MPC5XXX 2256 2257 When a board is reset during an i2c bus transfer 2258 chips might think that the current transfer is still 2259 in progress. Reset the slave devices by sending start 2260 commands until the slave device responds. 2261 2262 That's all that's required for CONFIG_HARD_I2C. 2263 2264 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT) 2265 then the following macros need to be defined (examples are 2266 from include/configs/lwmon.h): 2267 2268 I2C_INIT 2269 2270 (Optional). Any commands necessary to enable the I2C 2271 controller or configure ports. 2272 2273 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) 2274 2275 I2C_PORT 2276 2277 (Only for MPC8260 CPU). The I/O port to use (the code 2278 assumes both bits are on the same port). Valid values 2279 are 0..3 for ports A..D. 2280 2281 I2C_ACTIVE 2282 2283 The code necessary to make the I2C data line active 2284 (driven). If the data line is open collector, this 2285 define can be null. 2286 2287 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) 2288 2289 I2C_TRISTATE 2290 2291 The code necessary to make the I2C data line tri-stated 2292 (inactive). If the data line is open collector, this 2293 define can be null. 2294 2295 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) 2296 2297 I2C_READ 2298 2299 Code that returns true if the I2C data line is high, 2300 false if it is low. 2301 2302 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) 2303 2304 I2C_SDA(bit) 2305 2306 If <bit> is true, sets the I2C data line high. If it 2307 is false, it clears it (low). 2308 2309 eg: #define I2C_SDA(bit) \ 2310 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ 2311 else immr->im_cpm.cp_pbdat &= ~PB_SDA 2312 2313 I2C_SCL(bit) 2314 2315 If <bit> is true, sets the I2C clock line high. If it 2316 is false, it clears it (low). 2317 2318 eg: #define I2C_SCL(bit) \ 2319 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ 2320 else immr->im_cpm.cp_pbdat &= ~PB_SCL 2321 2322 I2C_DELAY 2323 2324 This delay is invoked four times per clock cycle so this 2325 controls the rate of data transfer. The data rate thus 2326 is 1 / (I2C_DELAY * 4). Often defined to be something 2327 like: 2328 2329 #define I2C_DELAY udelay(2) 2330 2331 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA 2332 2333 If your arch supports the generic GPIO framework (asm/gpio.h), 2334 then you may alternatively define the two GPIOs that are to be 2335 used as SCL / SDA. Any of the previous I2C_xxx macros will 2336 have GPIO-based defaults assigned to them as appropriate. 2337 2338 You should define these to the GPIO value as given directly to 2339 the generic GPIO functions. 2340 2341 CONFIG_SYS_I2C_INIT_BOARD 2342 2343 When a board is reset during an i2c bus transfer 2344 chips might think that the current transfer is still 2345 in progress. On some boards it is possible to access 2346 the i2c SCLK line directly, either by using the 2347 processor pin as a GPIO or by having a second pin 2348 connected to the bus. If this option is defined a 2349 custom i2c_init_board() routine in boards/xxx/board.c 2350 is run early in the boot sequence. 2351 2352 CONFIG_SYS_I2C_BOARD_LATE_INIT 2353 2354 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is 2355 defined a custom i2c_board_late_init() routine in 2356 boards/xxx/board.c is run AFTER the operations in i2c_init() 2357 is completed. This callpoint can be used to unreset i2c bus 2358 using CPU i2c controller register accesses for CPUs whose i2c 2359 controller provide such a method. It is called at the end of 2360 i2c_init() to allow i2c_init operations to setup the i2c bus 2361 controller on the CPU (e.g. setting bus speed & slave address). 2362 2363 CONFIG_I2CFAST (PPC405GP|PPC405EP only) 2364 2365 This option enables configuration of bi_iic_fast[] flags 2366 in u-boot bd_info structure based on u-boot environment 2367 variable "i2cfast". (see also i2cfast) 2368 2369 CONFIG_I2C_MULTI_BUS 2370 2371 This option allows the use of multiple I2C buses, each of which 2372 must have a controller. At any point in time, only one bus is 2373 active. To switch to a different bus, use the 'i2c dev' command. 2374 Note that bus numbering is zero-based. 2375 2376 CONFIG_SYS_I2C_NOPROBES 2377 2378 This option specifies a list of I2C devices that will be skipped 2379 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS 2380 is set, specify a list of bus-device pairs. Otherwise, specify 2381 a 1D array of device addresses 2382 2383 e.g. 2384 #undef CONFIG_I2C_MULTI_BUS 2385 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68} 2386 2387 will skip addresses 0x50 and 0x68 on a board with one I2C bus 2388 2389 #define CONFIG_I2C_MULTI_BUS 2390 #define CONFIG_SYS_I2C_NOPROBES {{0,0x50},{0,0x68},{1,0x54}} 2391 2392 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1 2393 2394 CONFIG_SYS_SPD_BUS_NUM 2395 2396 If defined, then this indicates the I2C bus number for DDR SPD. 2397 If not defined, then U-Boot assumes that SPD is on I2C bus 0. 2398 2399 CONFIG_SYS_RTC_BUS_NUM 2400 2401 If defined, then this indicates the I2C bus number for the RTC. 2402 If not defined, then U-Boot assumes that RTC is on I2C bus 0. 2403 2404 CONFIG_SYS_DTT_BUS_NUM 2405 2406 If defined, then this indicates the I2C bus number for the DTT. 2407 If not defined, then U-Boot assumes that DTT is on I2C bus 0. 2408 2409 CONFIG_SYS_I2C_DTT_ADDR: 2410 2411 If defined, specifies the I2C address of the DTT device. 2412 If not defined, then U-Boot uses predefined value for 2413 specified DTT device. 2414 2415 CONFIG_SOFT_I2C_READ_REPEATED_START 2416 2417 defining this will force the i2c_read() function in 2418 the soft_i2c driver to perform an I2C repeated start 2419 between writing the address pointer and reading the 2420 data. If this define is omitted the default behaviour 2421 of doing a stop-start sequence will be used. Most I2C 2422 devices can use either method, but some require one or 2423 the other. 2424 2425- SPI Support: CONFIG_SPI 2426 2427 Enables SPI driver (so far only tested with 2428 SPI EEPROM, also an instance works with Crystal A/D and 2429 D/As on the SACSng board) 2430 2431 CONFIG_SH_SPI 2432 2433 Enables the driver for SPI controller on SuperH. Currently 2434 only SH7757 is supported. 2435 2436 CONFIG_SOFT_SPI 2437 2438 Enables a software (bit-bang) SPI driver rather than 2439 using hardware support. This is a general purpose 2440 driver that only requires three general I/O port pins 2441 (two outputs, one input) to function. If this is 2442 defined, the board configuration must define several 2443 SPI configuration items (port pins to use, etc). For 2444 an example, see include/configs/sacsng.h. 2445 2446 CONFIG_HARD_SPI 2447 2448 Enables a hardware SPI driver for general-purpose reads 2449 and writes. As with CONFIG_SOFT_SPI, the board configuration 2450 must define a list of chip-select function pointers. 2451 Currently supported on some MPC8xxx processors. For an 2452 example, see include/configs/mpc8349emds.h. 2453 2454 CONFIG_MXC_SPI 2455 2456 Enables the driver for the SPI controllers on i.MX and MXC 2457 SoCs. Currently i.MX31/35/51 are supported. 2458 2459 CONFIG_SYS_SPI_MXC_WAIT 2460 Timeout for waiting until spi transfer completed. 2461 default: (CONFIG_SYS_HZ/100) /* 10 ms */ 2462 2463- FPGA Support: CONFIG_FPGA 2464 2465 Enables FPGA subsystem. 2466 2467 CONFIG_FPGA_<vendor> 2468 2469 Enables support for specific chip vendors. 2470 (ALTERA, XILINX) 2471 2472 CONFIG_FPGA_<family> 2473 2474 Enables support for FPGA family. 2475 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX) 2476 2477 CONFIG_FPGA_COUNT 2478 2479 Specify the number of FPGA devices to support. 2480 2481 CONFIG_CMD_FPGA_LOADMK 2482 2483 Enable support for fpga loadmk command 2484 2485 CONFIG_CMD_FPGA_LOADP 2486 2487 Enable support for fpga loadp command - load partial bitstream 2488 2489 CONFIG_CMD_FPGA_LOADBP 2490 2491 Enable support for fpga loadbp command - load partial bitstream 2492 (Xilinx only) 2493 2494 CONFIG_SYS_FPGA_PROG_FEEDBACK 2495 2496 Enable printing of hash marks during FPGA configuration. 2497 2498 CONFIG_SYS_FPGA_CHECK_BUSY 2499 2500 Enable checks on FPGA configuration interface busy 2501 status by the configuration function. This option 2502 will require a board or device specific function to 2503 be written. 2504 2505 CONFIG_FPGA_DELAY 2506 2507 If defined, a function that provides delays in the FPGA 2508 configuration driver. 2509 2510 CONFIG_SYS_FPGA_CHECK_CTRLC 2511 Allow Control-C to interrupt FPGA configuration 2512 2513 CONFIG_SYS_FPGA_CHECK_ERROR 2514 2515 Check for configuration errors during FPGA bitfile 2516 loading. For example, abort during Virtex II 2517 configuration if the INIT_B line goes low (which 2518 indicated a CRC error). 2519 2520 CONFIG_SYS_FPGA_WAIT_INIT 2521 2522 Maximum time to wait for the INIT_B line to de-assert 2523 after PROB_B has been de-asserted during a Virtex II 2524 FPGA configuration sequence. The default time is 500 2525 ms. 2526 2527 CONFIG_SYS_FPGA_WAIT_BUSY 2528 2529 Maximum time to wait for BUSY to de-assert during 2530 Virtex II FPGA configuration. The default is 5 ms. 2531 2532 CONFIG_SYS_FPGA_WAIT_CONFIG 2533 2534 Time to wait after FPGA configuration. The default is 2535 200 ms. 2536 2537- Configuration Management: 2538 CONFIG_BUILD_TARGET 2539 2540 Some SoCs need special image types (e.g. U-Boot binary 2541 with a special header) as build targets. By defining 2542 CONFIG_BUILD_TARGET in the SoC / board header, this 2543 special image will be automatically built upon calling 2544 make / buildman. 2545 2546 CONFIG_IDENT_STRING 2547 2548 If defined, this string will be added to the U-Boot 2549 version information (U_BOOT_VERSION) 2550 2551- Vendor Parameter Protection: 2552 2553 U-Boot considers the values of the environment 2554 variables "serial#" (Board Serial Number) and 2555 "ethaddr" (Ethernet Address) to be parameters that 2556 are set once by the board vendor / manufacturer, and 2557 protects these variables from casual modification by 2558 the user. Once set, these variables are read-only, 2559 and write or delete attempts are rejected. You can 2560 change this behaviour: 2561 2562 If CONFIG_ENV_OVERWRITE is #defined in your config 2563 file, the write protection for vendor parameters is 2564 completely disabled. Anybody can change or delete 2565 these parameters. 2566 2567 Alternatively, if you define _both_ an ethaddr in the 2568 default env _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 2569 Ethernet address is installed in the environment, 2570 which can be changed exactly ONCE by the user. [The 2571 serial# is unaffected by this, i. e. it remains 2572 read-only.] 2573 2574 The same can be accomplished in a more flexible way 2575 for any variable by configuring the type of access 2576 to allow for those variables in the ".flags" variable 2577 or define CONFIG_ENV_FLAGS_LIST_STATIC. 2578 2579- Protected RAM: 2580 CONFIG_PRAM 2581 2582 Define this variable to enable the reservation of 2583 "protected RAM", i. e. RAM which is not overwritten 2584 by U-Boot. Define CONFIG_PRAM to hold the number of 2585 kB you want to reserve for pRAM. You can overwrite 2586 this default value by defining an environment 2587 variable "pram" to the number of kB you want to 2588 reserve. Note that the board info structure will 2589 still show the full amount of RAM. If pRAM is 2590 reserved, a new environment variable "mem" will 2591 automatically be defined to hold the amount of 2592 remaining RAM in a form that can be passed as boot 2593 argument to Linux, for instance like that: 2594 2595 setenv bootargs ... mem=\${mem} 2596 saveenv 2597 2598 This way you can tell Linux not to use this memory, 2599 either, which results in a memory region that will 2600 not be affected by reboots. 2601 2602 *WARNING* If your board configuration uses automatic 2603 detection of the RAM size, you must make sure that 2604 this memory test is non-destructive. So far, the 2605 following board configurations are known to be 2606 "pRAM-clean": 2607 2608 IVMS8, IVML24, SPD8xx, TQM8xxL, 2609 HERMES, IP860, RPXlite, LWMON, 2610 FLAGADM, TQM8260 2611 2612- Access to physical memory region (> 4GB) 2613 Some basic support is provided for operations on memory not 2614 normally accessible to U-Boot - e.g. some architectures 2615 support access to more than 4GB of memory on 32-bit 2616 machines using physical address extension or similar. 2617 Define CONFIG_PHYSMEM to access this basic support, which 2618 currently only supports clearing the memory. 2619 2620- Error Recovery: 2621 CONFIG_PANIC_HANG 2622 2623 Define this variable to stop the system in case of a 2624 fatal error, so that you have to reset it manually. 2625 This is probably NOT a good idea for an embedded 2626 system where you want the system to reboot 2627 automatically as fast as possible, but it may be 2628 useful during development since you can try to debug 2629 the conditions that lead to the situation. 2630 2631 CONFIG_NET_RETRY_COUNT 2632 2633 This variable defines the number of retries for 2634 network operations like ARP, RARP, TFTP, or BOOTP 2635 before giving up the operation. If not defined, a 2636 default value of 5 is used. 2637 2638 CONFIG_ARP_TIMEOUT 2639 2640 Timeout waiting for an ARP reply in milliseconds. 2641 2642 CONFIG_NFS_TIMEOUT 2643 2644 Timeout in milliseconds used in NFS protocol. 2645 If you encounter "ERROR: Cannot umount" in nfs command, 2646 try longer timeout such as 2647 #define CONFIG_NFS_TIMEOUT 10000UL 2648 2649- Command Interpreter: 2650 CONFIG_AUTO_COMPLETE 2651 2652 Enable auto completion of commands using TAB. 2653 2654 CONFIG_SYS_PROMPT_HUSH_PS2 2655 2656 This defines the secondary prompt string, which is 2657 printed when the command interpreter needs more input 2658 to complete a command. Usually "> ". 2659 2660 Note: 2661 2662 In the current implementation, the local variables 2663 space and global environment variables space are 2664 separated. Local variables are those you define by 2665 simply typing `name=value'. To access a local 2666 variable later on, you have write `$name' or 2667 `${name}'; to execute the contents of a variable 2668 directly type `$name' at the command prompt. 2669 2670 Global environment variables are those you use 2671 setenv/printenv to work with. To run a command stored 2672 in such a variable, you need to use the run command, 2673 and you must not use the '$' sign to access them. 2674 2675 To store commands and special characters in a 2676 variable, please use double quotation marks 2677 surrounding the whole text of the variable, instead 2678 of the backslashes before semicolons and special 2679 symbols. 2680 2681- Command Line Editing and History: 2682 CONFIG_CMDLINE_EDITING 2683 2684 Enable editing and History functions for interactive 2685 command line input operations 2686 2687- Command Line PS1/PS2 support: 2688 CONFIG_CMDLINE_PS_SUPPORT 2689 2690 Enable support for changing the command prompt string 2691 at run-time. Only static string is supported so far. 2692 The string is obtained from environment variables PS1 2693 and PS2. 2694 2695- Default Environment: 2696 CONFIG_EXTRA_ENV_SETTINGS 2697 2698 Define this to contain any number of null terminated 2699 strings (variable = value pairs) that will be part of 2700 the default environment compiled into the boot image. 2701 2702 For example, place something like this in your 2703 board's config file: 2704 2705 #define CONFIG_EXTRA_ENV_SETTINGS \ 2706 "myvar1=value1\0" \ 2707 "myvar2=value2\0" 2708 2709 Warning: This method is based on knowledge about the 2710 internal format how the environment is stored by the 2711 U-Boot code. This is NOT an official, exported 2712 interface! Although it is unlikely that this format 2713 will change soon, there is no guarantee either. 2714 You better know what you are doing here. 2715 2716 Note: overly (ab)use of the default environment is 2717 discouraged. Make sure to check other ways to preset 2718 the environment like the "source" command or the 2719 boot command first. 2720 2721 CONFIG_ENV_VARS_UBOOT_CONFIG 2722 2723 Define this in order to add variables describing the 2724 U-Boot build configuration to the default environment. 2725 These will be named arch, cpu, board, vendor, and soc. 2726 2727 Enabling this option will cause the following to be defined: 2728 2729 - CONFIG_SYS_ARCH 2730 - CONFIG_SYS_CPU 2731 - CONFIG_SYS_BOARD 2732 - CONFIG_SYS_VENDOR 2733 - CONFIG_SYS_SOC 2734 2735 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG 2736 2737 Define this in order to add variables describing certain 2738 run-time determined information about the hardware to the 2739 environment. These will be named board_name, board_rev. 2740 2741 CONFIG_DELAY_ENVIRONMENT 2742 2743 Normally the environment is loaded when the board is 2744 initialised so that it is available to U-Boot. This inhibits 2745 that so that the environment is not available until 2746 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL 2747 this is instead controlled by the value of 2748 /config/load-environment. 2749 2750- DataFlash Support: 2751 CONFIG_HAS_DATAFLASH 2752 2753 Defining this option enables DataFlash features and 2754 allows to read/write in Dataflash via the standard 2755 commands cp, md... 2756 2757- Serial Flash support 2758 CONFIG_CMD_SF 2759 2760 Defining this option enables SPI flash commands 2761 'sf probe/read/write/erase/update'. 2762 2763 Usage requires an initial 'probe' to define the serial 2764 flash parameters, followed by read/write/erase/update 2765 commands. 2766 2767 The following defaults may be provided by the platform 2768 to handle the common case when only a single serial 2769 flash is present on the system. 2770 2771 CONFIG_SF_DEFAULT_BUS Bus identifier 2772 CONFIG_SF_DEFAULT_CS Chip-select 2773 CONFIG_SF_DEFAULT_MODE (see include/spi.h) 2774 CONFIG_SF_DEFAULT_SPEED in Hz 2775 2776 CONFIG_CMD_SF_TEST 2777 2778 Define this option to include a destructive SPI flash 2779 test ('sf test'). 2780 2781 CONFIG_SF_DUAL_FLASH Dual flash memories 2782 2783 Define this option to use dual flash support where two flash 2784 memories can be connected with a given cs line. 2785 Currently Xilinx Zynq qspi supports these type of connections. 2786 2787- SystemACE Support: 2788 CONFIG_SYSTEMACE 2789 2790 Adding this option adds support for Xilinx SystemACE 2791 chips attached via some sort of local bus. The address 2792 of the chip must also be defined in the 2793 CONFIG_SYS_SYSTEMACE_BASE macro. For example: 2794 2795 #define CONFIG_SYSTEMACE 2796 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000 2797 2798 When SystemACE support is added, the "ace" device type 2799 becomes available to the fat commands, i.e. fatls. 2800 2801- TFTP Fixed UDP Port: 2802 CONFIG_TFTP_PORT 2803 2804 If this is defined, the environment variable tftpsrcp 2805 is used to supply the TFTP UDP source port value. 2806 If tftpsrcp isn't defined, the normal pseudo-random port 2807 number generator is used. 2808 2809 Also, the environment variable tftpdstp is used to supply 2810 the TFTP UDP destination port value. If tftpdstp isn't 2811 defined, the normal port 69 is used. 2812 2813 The purpose for tftpsrcp is to allow a TFTP server to 2814 blindly start the TFTP transfer using the pre-configured 2815 target IP address and UDP port. This has the effect of 2816 "punching through" the (Windows XP) firewall, allowing 2817 the remainder of the TFTP transfer to proceed normally. 2818 A better solution is to properly configure the firewall, 2819 but sometimes that is not allowed. 2820 2821- Hashing support: 2822 CONFIG_CMD_HASH 2823 2824 This enables a generic 'hash' command which can produce 2825 hashes / digests from a few algorithms (e.g. SHA1, SHA256). 2826 2827 CONFIG_HASH_VERIFY 2828 2829 Enable the hash verify command (hash -v). This adds to code 2830 size a little. 2831 2832 CONFIG_SHA1 - This option enables support of hashing using SHA1 2833 algorithm. The hash is calculated in software. 2834 CONFIG_SHA256 - This option enables support of hashing using 2835 SHA256 algorithm. The hash is calculated in software. 2836 CONFIG_SHA_HW_ACCEL - This option enables hardware acceleration 2837 for SHA1/SHA256 hashing. 2838 This affects the 'hash' command and also the 2839 hash_lookup_algo() function. 2840 CONFIG_SHA_PROG_HW_ACCEL - This option enables 2841 hardware-acceleration for SHA1/SHA256 progressive hashing. 2842 Data can be streamed in a block at a time and the hashing 2843 is performed in hardware. 2844 2845 Note: There is also a sha1sum command, which should perhaps 2846 be deprecated in favour of 'hash sha1'. 2847 2848- Freescale i.MX specific commands: 2849 CONFIG_CMD_HDMIDETECT 2850 This enables 'hdmidet' command which returns true if an 2851 HDMI monitor is detected. This command is i.MX 6 specific. 2852 2853 CONFIG_CMD_BMODE 2854 This enables the 'bmode' (bootmode) command for forcing 2855 a boot from specific media. 2856 2857 This is useful for forcing the ROM's usb downloader to 2858 activate upon a watchdog reset which is nice when iterating 2859 on U-Boot. Using the reset button or running bmode normal 2860 will set it back to normal. This command currently 2861 supports i.MX53 and i.MX6. 2862 2863- bootcount support: 2864 CONFIG_BOOTCOUNT_LIMIT 2865 2866 This enables the bootcounter support, see: 2867 http://www.denx.de/wiki/DULG/UBootBootCountLimit 2868 2869 CONFIG_AT91SAM9XE 2870 enable special bootcounter support on at91sam9xe based boards. 2871 CONFIG_SOC_DA8XX 2872 enable special bootcounter support on da850 based boards. 2873 CONFIG_BOOTCOUNT_RAM 2874 enable support for the bootcounter in RAM 2875 CONFIG_BOOTCOUNT_I2C 2876 enable support for the bootcounter on an i2c (like RTC) device. 2877 CONFIG_SYS_I2C_RTC_ADDR = i2c chip address 2878 CONFIG_SYS_BOOTCOUNT_ADDR = i2c addr which is used for 2879 the bootcounter. 2880 CONFIG_BOOTCOUNT_ALEN = address len 2881 2882- Show boot progress: 2883 CONFIG_SHOW_BOOT_PROGRESS 2884 2885 Defining this option allows to add some board- 2886 specific code (calling a user-provided function 2887 "show_boot_progress(int)") that enables you to show 2888 the system's boot progress on some display (for 2889 example, some LED's) on your board. At the moment, 2890 the following checkpoints are implemented: 2891 2892 2893Legacy uImage format: 2894 2895 Arg Where When 2896 1 common/cmd_bootm.c before attempting to boot an image 2897 -1 common/cmd_bootm.c Image header has bad magic number 2898 2 common/cmd_bootm.c Image header has correct magic number 2899 -2 common/cmd_bootm.c Image header has bad checksum 2900 3 common/cmd_bootm.c Image header has correct checksum 2901 -3 common/cmd_bootm.c Image data has bad checksum 2902 4 common/cmd_bootm.c Image data has correct checksum 2903 -4 common/cmd_bootm.c Image is for unsupported architecture 2904 5 common/cmd_bootm.c Architecture check OK 2905 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi) 2906 6 common/cmd_bootm.c Image Type check OK 2907 -6 common/cmd_bootm.c gunzip uncompression error 2908 -7 common/cmd_bootm.c Unimplemented compression type 2909 7 common/cmd_bootm.c Uncompression OK 2910 8 common/cmd_bootm.c No uncompress/copy overwrite error 2911 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 2912 2913 9 common/image.c Start initial ramdisk verification 2914 -10 common/image.c Ramdisk header has bad magic number 2915 -11 common/image.c Ramdisk header has bad checksum 2916 10 common/image.c Ramdisk header is OK 2917 -12 common/image.c Ramdisk data has bad checksum 2918 11 common/image.c Ramdisk data has correct checksum 2919 12 common/image.c Ramdisk verification complete, start loading 2920 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk) 2921 13 common/image.c Start multifile image verification 2922 14 common/image.c No initial ramdisk, no multifile, continue. 2923 2924 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS 2925 2926 -30 arch/powerpc/lib/board.c Fatal error, hang the system 2927 -31 post/post.c POST test failed, detected by post_output_backlog() 2928 -32 post/post.c POST test failed, detected by post_run_single() 2929 2930 34 common/cmd_doc.c before loading a Image from a DOC device 2931 -35 common/cmd_doc.c Bad usage of "doc" command 2932 35 common/cmd_doc.c correct usage of "doc" command 2933 -36 common/cmd_doc.c No boot device 2934 36 common/cmd_doc.c correct boot device 2935 -37 common/cmd_doc.c Unknown Chip ID on boot device 2936 37 common/cmd_doc.c correct chip ID found, device available 2937 -38 common/cmd_doc.c Read Error on boot device 2938 38 common/cmd_doc.c reading Image header from DOC device OK 2939 -39 common/cmd_doc.c Image header has bad magic number 2940 39 common/cmd_doc.c Image header has correct magic number 2941 -40 common/cmd_doc.c Error reading Image from DOC device 2942 40 common/cmd_doc.c Image header has correct magic number 2943 41 common/cmd_ide.c before loading a Image from a IDE device 2944 -42 common/cmd_ide.c Bad usage of "ide" command 2945 42 common/cmd_ide.c correct usage of "ide" command 2946 -43 common/cmd_ide.c No boot device 2947 43 common/cmd_ide.c boot device found 2948 -44 common/cmd_ide.c Device not available 2949 44 common/cmd_ide.c Device available 2950 -45 common/cmd_ide.c wrong partition selected 2951 45 common/cmd_ide.c partition selected 2952 -46 common/cmd_ide.c Unknown partition table 2953 46 common/cmd_ide.c valid partition table found 2954 -47 common/cmd_ide.c Invalid partition type 2955 47 common/cmd_ide.c correct partition type 2956 -48 common/cmd_ide.c Error reading Image Header on boot device 2957 48 common/cmd_ide.c reading Image Header from IDE device OK 2958 -49 common/cmd_ide.c Image header has bad magic number 2959 49 common/cmd_ide.c Image header has correct magic number 2960 -50 common/cmd_ide.c Image header has bad checksum 2961 50 common/cmd_ide.c Image header has correct checksum 2962 -51 common/cmd_ide.c Error reading Image from IDE device 2963 51 common/cmd_ide.c reading Image from IDE device OK 2964 52 common/cmd_nand.c before loading a Image from a NAND device 2965 -53 common/cmd_nand.c Bad usage of "nand" command 2966 53 common/cmd_nand.c correct usage of "nand" command 2967 -54 common/cmd_nand.c No boot device 2968 54 common/cmd_nand.c boot device found 2969 -55 common/cmd_nand.c Unknown Chip ID on boot device 2970 55 common/cmd_nand.c correct chip ID found, device available 2971 -56 common/cmd_nand.c Error reading Image Header on boot device 2972 56 common/cmd_nand.c reading Image Header from NAND device OK 2973 -57 common/cmd_nand.c Image header has bad magic number 2974 57 common/cmd_nand.c Image header has correct magic number 2975 -58 common/cmd_nand.c Error reading Image from NAND device 2976 58 common/cmd_nand.c reading Image from NAND device OK 2977 2978 -60 common/env_common.c Environment has a bad CRC, using default 2979 2980 64 net/eth.c starting with Ethernet configuration. 2981 -64 net/eth.c no Ethernet found. 2982 65 net/eth.c Ethernet found. 2983 2984 -80 common/cmd_net.c usage wrong 2985 80 common/cmd_net.c before calling net_loop() 2986 -81 common/cmd_net.c some error in net_loop() occurred 2987 81 common/cmd_net.c net_loop() back without error 2988 -82 common/cmd_net.c size == 0 (File with size 0 loaded) 2989 82 common/cmd_net.c trying automatic boot 2990 83 common/cmd_net.c running "source" command 2991 -83 common/cmd_net.c some error in automatic boot or "source" command 2992 84 common/cmd_net.c end without errors 2993 2994FIT uImage format: 2995 2996 Arg Where When 2997 100 common/cmd_bootm.c Kernel FIT Image has correct format 2998 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format 2999 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration 3000 -101 common/cmd_bootm.c Can't get configuration for kernel subimage 3001 102 common/cmd_bootm.c Kernel unit name specified 3002 -103 common/cmd_bootm.c Can't get kernel subimage node offset 3003 103 common/cmd_bootm.c Found configuration node 3004 104 common/cmd_bootm.c Got kernel subimage node offset 3005 -104 common/cmd_bootm.c Kernel subimage hash verification failed 3006 105 common/cmd_bootm.c Kernel subimage hash verification OK 3007 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture 3008 106 common/cmd_bootm.c Architecture check OK 3009 -106 common/cmd_bootm.c Kernel subimage has wrong type 3010 107 common/cmd_bootm.c Kernel subimage type OK 3011 -107 common/cmd_bootm.c Can't get kernel subimage data/size 3012 108 common/cmd_bootm.c Got kernel subimage data/size 3013 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT) 3014 -109 common/cmd_bootm.c Can't get kernel subimage type 3015 -110 common/cmd_bootm.c Can't get kernel subimage comp 3016 -111 common/cmd_bootm.c Can't get kernel subimage os 3017 -112 common/cmd_bootm.c Can't get kernel subimage load address 3018 -113 common/cmd_bootm.c Image uncompress/copy overwrite error 3019 3020 120 common/image.c Start initial ramdisk verification 3021 -120 common/image.c Ramdisk FIT image has incorrect format 3022 121 common/image.c Ramdisk FIT image has correct format 3023 122 common/image.c No ramdisk subimage unit name, using configuration 3024 -122 common/image.c Can't get configuration for ramdisk subimage 3025 123 common/image.c Ramdisk unit name specified 3026 -124 common/image.c Can't get ramdisk subimage node offset 3027 125 common/image.c Got ramdisk subimage node offset 3028 -125 common/image.c Ramdisk subimage hash verification failed 3029 126 common/image.c Ramdisk subimage hash verification OK 3030 -126 common/image.c Ramdisk subimage for unsupported architecture 3031 127 common/image.c Architecture check OK 3032 -127 common/image.c Can't get ramdisk subimage data/size 3033 128 common/image.c Got ramdisk subimage data/size 3034 129 common/image.c Can't get ramdisk load address 3035 -129 common/image.c Got ramdisk load address 3036 3037 -130 common/cmd_doc.c Incorrect FIT image format 3038 131 common/cmd_doc.c FIT image format OK 3039 3040 -140 common/cmd_ide.c Incorrect FIT image format 3041 141 common/cmd_ide.c FIT image format OK 3042 3043 -150 common/cmd_nand.c Incorrect FIT image format 3044 151 common/cmd_nand.c FIT image format OK 3045 3046- legacy image format: 3047 CONFIG_IMAGE_FORMAT_LEGACY 3048 enables the legacy image format support in U-Boot. 3049 3050 Default: 3051 enabled if CONFIG_FIT_SIGNATURE is not defined. 3052 3053 CONFIG_DISABLE_IMAGE_LEGACY 3054 disable the legacy image format 3055 3056 This define is introduced, as the legacy image format is 3057 enabled per default for backward compatibility. 3058 3059- FIT image support: 3060 CONFIG_FIT_DISABLE_SHA256 3061 Supporting SHA256 hashes has quite an impact on binary size. 3062 For constrained systems sha256 hash support can be disabled 3063 with this option. 3064 3065 TODO(sjg@chromium.org): Adjust this option to be positive, 3066 and move it to Kconfig 3067 3068- Standalone program support: 3069 CONFIG_STANDALONE_LOAD_ADDR 3070 3071 This option defines a board specific value for the 3072 address where standalone program gets loaded, thus 3073 overwriting the architecture dependent default 3074 settings. 3075 3076- Frame Buffer Address: 3077 CONFIG_FB_ADDR 3078 3079 Define CONFIG_FB_ADDR if you want to use specific 3080 address for frame buffer. This is typically the case 3081 when using a graphics controller has separate video 3082 memory. U-Boot will then place the frame buffer at 3083 the given address instead of dynamically reserving it 3084 in system RAM by calling lcd_setmem(), which grabs 3085 the memory for the frame buffer depending on the 3086 configured panel size. 3087 3088 Please see board_init_f function. 3089 3090- Automatic software updates via TFTP server 3091 CONFIG_UPDATE_TFTP 3092 CONFIG_UPDATE_TFTP_CNT_MAX 3093 CONFIG_UPDATE_TFTP_MSEC_MAX 3094 3095 These options enable and control the auto-update feature; 3096 for a more detailed description refer to doc/README.update. 3097 3098- MTD Support (mtdparts command, UBI support) 3099 CONFIG_MTD_DEVICE 3100 3101 Adds the MTD device infrastructure from the Linux kernel. 3102 Needed for mtdparts command support. 3103 3104 CONFIG_MTD_PARTITIONS 3105 3106 Adds the MTD partitioning infrastructure from the Linux 3107 kernel. Needed for UBI support. 3108 3109- UBI support 3110 CONFIG_CMD_UBI 3111 3112 Adds commands for interacting with MTD partitions formatted 3113 with the UBI flash translation layer 3114 3115 Requires also defining CONFIG_RBTREE 3116 3117 CONFIG_UBI_SILENCE_MSG 3118 3119 Make the verbose messages from UBI stop printing. This leaves 3120 warnings and errors enabled. 3121 3122 3123 CONFIG_MTD_UBI_WL_THRESHOLD 3124 This parameter defines the maximum difference between the highest 3125 erase counter value and the lowest erase counter value of eraseblocks 3126 of UBI devices. When this threshold is exceeded, UBI starts performing 3127 wear leveling by means of moving data from eraseblock with low erase 3128 counter to eraseblocks with high erase counter. 3129 3130 The default value should be OK for SLC NAND flashes, NOR flashes and 3131 other flashes which have eraseblock life-cycle 100000 or more. 3132 However, in case of MLC NAND flashes which typically have eraseblock 3133 life-cycle less than 10000, the threshold should be lessened (e.g., 3134 to 128 or 256, although it does not have to be power of 2). 3135 3136 default: 4096 3137 3138 CONFIG_MTD_UBI_BEB_LIMIT 3139 This option specifies the maximum bad physical eraseblocks UBI 3140 expects on the MTD device (per 1024 eraseblocks). If the 3141 underlying flash does not admit of bad eraseblocks (e.g. NOR 3142 flash), this value is ignored. 3143 3144 NAND datasheets often specify the minimum and maximum NVM 3145 (Number of Valid Blocks) for the flashes' endurance lifetime. 3146 The maximum expected bad eraseblocks per 1024 eraseblocks 3147 then can be calculated as "1024 * (1 - MinNVB / MaxNVB)", 3148 which gives 20 for most NANDs (MaxNVB is basically the total 3149 count of eraseblocks on the chip). 3150 3151 To put it differently, if this value is 20, UBI will try to 3152 reserve about 1.9% of physical eraseblocks for bad blocks 3153 handling. And that will be 1.9% of eraseblocks on the entire 3154 NAND chip, not just the MTD partition UBI attaches. This means 3155 that if you have, say, a NAND flash chip admits maximum 40 bad 3156 eraseblocks, and it is split on two MTD partitions of the same 3157 size, UBI will reserve 40 eraseblocks when attaching a 3158 partition. 3159 3160 default: 20 3161 3162 CONFIG_MTD_UBI_FASTMAP 3163 Fastmap is a mechanism which allows attaching an UBI device 3164 in nearly constant time. Instead of scanning the whole MTD device it 3165 only has to locate a checkpoint (called fastmap) on the device. 3166 The on-flash fastmap contains all information needed to attach 3167 the device. Using fastmap makes only sense on large devices where 3168 attaching by scanning takes long. UBI will not automatically install 3169 a fastmap on old images, but you can set the UBI parameter 3170 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT to 1 if you want so. Please note 3171 that fastmap-enabled images are still usable with UBI implementations 3172 without fastmap support. On typical flash devices the whole fastmap 3173 fits into one PEB. UBI will reserve PEBs to hold two fastmaps. 3174 3175 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT 3176 Set this parameter to enable fastmap automatically on images 3177 without a fastmap. 3178 default: 0 3179 3180 CONFIG_MTD_UBI_FM_DEBUG 3181 Enable UBI fastmap debug 3182 default: 0 3183 3184- UBIFS support 3185 CONFIG_CMD_UBIFS 3186 3187 Adds commands for interacting with UBI volumes formatted as 3188 UBIFS. UBIFS is read-only in u-boot. 3189 3190 Requires UBI support as well as CONFIG_LZO 3191 3192 CONFIG_UBIFS_SILENCE_MSG 3193 3194 Make the verbose messages from UBIFS stop printing. This leaves 3195 warnings and errors enabled. 3196 3197- SPL framework 3198 CONFIG_SPL 3199 Enable building of SPL globally. 3200 3201 CONFIG_SPL_LDSCRIPT 3202 LDSCRIPT for linking the SPL binary. 3203 3204 CONFIG_SPL_MAX_FOOTPRINT 3205 Maximum size in memory allocated to the SPL, BSS included. 3206 When defined, the linker checks that the actual memory 3207 used by SPL from _start to __bss_end does not exceed it. 3208 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 3209 must not be both defined at the same time. 3210 3211 CONFIG_SPL_MAX_SIZE 3212 Maximum size of the SPL image (text, data, rodata, and 3213 linker lists sections), BSS excluded. 3214 When defined, the linker checks that the actual size does 3215 not exceed it. 3216 3217 CONFIG_SPL_TEXT_BASE 3218 TEXT_BASE for linking the SPL binary. 3219 3220 CONFIG_SPL_RELOC_TEXT_BASE 3221 Address to relocate to. If unspecified, this is equal to 3222 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done). 3223 3224 CONFIG_SPL_BSS_START_ADDR 3225 Link address for the BSS within the SPL binary. 3226 3227 CONFIG_SPL_BSS_MAX_SIZE 3228 Maximum size in memory allocated to the SPL BSS. 3229 When defined, the linker checks that the actual memory used 3230 by SPL from __bss_start to __bss_end does not exceed it. 3231 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 3232 must not be both defined at the same time. 3233 3234 CONFIG_SPL_STACK 3235 Adress of the start of the stack SPL will use 3236 3237 CONFIG_SPL_PANIC_ON_RAW_IMAGE 3238 When defined, SPL will panic() if the image it has 3239 loaded does not have a signature. 3240 Defining this is useful when code which loads images 3241 in SPL cannot guarantee that absolutely all read errors 3242 will be caught. 3243 An example is the LPC32XX MLC NAND driver, which will 3244 consider that a completely unreadable NAND block is bad, 3245 and thus should be skipped silently. 3246 3247 CONFIG_SPL_RELOC_STACK 3248 Adress of the start of the stack SPL will use after 3249 relocation. If unspecified, this is equal to 3250 CONFIG_SPL_STACK. 3251 3252 CONFIG_SYS_SPL_MALLOC_START 3253 Starting address of the malloc pool used in SPL. 3254 When this option is set the full malloc is used in SPL and 3255 it is set up by spl_init() and before that, the simple malloc() 3256 can be used if CONFIG_SYS_MALLOC_F is defined. 3257 3258 CONFIG_SYS_SPL_MALLOC_SIZE 3259 The size of the malloc pool used in SPL. 3260 3261 CONFIG_SPL_FRAMEWORK 3262 Enable the SPL framework under common/. This framework 3263 supports MMC, NAND and YMODEM loading of U-Boot and NAND 3264 NAND loading of the Linux Kernel. 3265 3266 CONFIG_SPL_OS_BOOT 3267 Enable booting directly to an OS from SPL. 3268 See also: doc/README.falcon 3269 3270 CONFIG_SPL_DISPLAY_PRINT 3271 For ARM, enable an optional function to print more information 3272 about the running system. 3273 3274 CONFIG_SPL_INIT_MINIMAL 3275 Arch init code should be built for a very small image 3276 3277 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_PARTITION 3278 Partition on the MMC to load U-Boot from when the MMC is being 3279 used in raw mode 3280 3281 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR 3282 Sector to load kernel uImage from when MMC is being 3283 used in raw mode (for Falcon mode) 3284 3285 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR, 3286 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS 3287 Sector and number of sectors to load kernel argument 3288 parameters from when MMC is being used in raw mode 3289 (for falcon mode) 3290 3291 CONFIG_SYS_MMCSD_FS_BOOT_PARTITION 3292 Partition on the MMC to load U-Boot from when the MMC is being 3293 used in fs mode 3294 3295 CONFIG_SPL_FS_LOAD_PAYLOAD_NAME 3296 Filename to read to load U-Boot when reading from filesystem 3297 3298 CONFIG_SPL_FS_LOAD_KERNEL_NAME 3299 Filename to read to load kernel uImage when reading 3300 from filesystem (for Falcon mode) 3301 3302 CONFIG_SPL_FS_LOAD_ARGS_NAME 3303 Filename to read to load kernel argument parameters 3304 when reading from filesystem (for Falcon mode) 3305 3306 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND 3307 Set this for NAND SPL on PPC mpc83xx targets, so that 3308 start.S waits for the rest of the SPL to load before 3309 continuing (the hardware starts execution after just 3310 loading the first page rather than the full 4K). 3311 3312 CONFIG_SPL_SKIP_RELOCATE 3313 Avoid SPL relocation 3314 3315 CONFIG_SPL_NAND_BASE 3316 Include nand_base.c in the SPL. Requires 3317 CONFIG_SPL_NAND_DRIVERS. 3318 3319 CONFIG_SPL_NAND_DRIVERS 3320 SPL uses normal NAND drivers, not minimal drivers. 3321 3322 CONFIG_SPL_NAND_ECC 3323 Include standard software ECC in the SPL 3324 3325 CONFIG_SPL_NAND_SIMPLE 3326 Support for NAND boot using simple NAND drivers that 3327 expose the cmd_ctrl() interface. 3328 3329 CONFIG_SPL_UBI 3330 Support for a lightweight UBI (fastmap) scanner and 3331 loader 3332 3333 CONFIG_SPL_NAND_RAW_ONLY 3334 Support to boot only raw u-boot.bin images. Use this only 3335 if you need to save space. 3336 3337 CONFIG_SPL_COMMON_INIT_DDR 3338 Set for common ddr init with serial presence detect in 3339 SPL binary. 3340 3341 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT, 3342 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE, 3343 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS, 3344 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE, 3345 CONFIG_SYS_NAND_ECCBYTES 3346 Defines the size and behavior of the NAND that SPL uses 3347 to read U-Boot 3348 3349 CONFIG_SPL_NAND_BOOT 3350 Add support NAND boot 3351 3352 CONFIG_SYS_NAND_U_BOOT_OFFS 3353 Location in NAND to read U-Boot from 3354 3355 CONFIG_SYS_NAND_U_BOOT_DST 3356 Location in memory to load U-Boot to 3357 3358 CONFIG_SYS_NAND_U_BOOT_SIZE 3359 Size of image to load 3360 3361 CONFIG_SYS_NAND_U_BOOT_START 3362 Entry point in loaded image to jump to 3363 3364 CONFIG_SYS_NAND_HW_ECC_OOBFIRST 3365 Define this if you need to first read the OOB and then the 3366 data. This is used, for example, on davinci platforms. 3367 3368 CONFIG_SPL_OMAP3_ID_NAND 3369 Support for an OMAP3-specific set of functions to return the 3370 ID and MFR of the first attached NAND chip, if present. 3371 3372 CONFIG_SPL_RAM_DEVICE 3373 Support for running image already present in ram, in SPL binary 3374 3375 CONFIG_SPL_PAD_TO 3376 Image offset to which the SPL should be padded before appending 3377 the SPL payload. By default, this is defined as 3378 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 3379 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 3380 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 3381 3382 CONFIG_SPL_TARGET 3383 Final target image containing SPL and payload. Some SPLs 3384 use an arch-specific makefile fragment instead, for 3385 example if more than one image needs to be produced. 3386 3387 CONFIG_FIT_SPL_PRINT 3388 Printing information about a FIT image adds quite a bit of 3389 code to SPL. So this is normally disabled in SPL. Use this 3390 option to re-enable it. This will affect the output of the 3391 bootm command when booting a FIT image. 3392 3393- TPL framework 3394 CONFIG_TPL 3395 Enable building of TPL globally. 3396 3397 CONFIG_TPL_PAD_TO 3398 Image offset to which the TPL should be padded before appending 3399 the TPL payload. By default, this is defined as 3400 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 3401 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 3402 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 3403 3404- Interrupt support (PPC): 3405 3406 There are common interrupt_init() and timer_interrupt() 3407 for all PPC archs. interrupt_init() calls interrupt_init_cpu() 3408 for CPU specific initialization. interrupt_init_cpu() 3409 should set decrementer_count to appropriate value. If 3410 CPU resets decrementer automatically after interrupt 3411 (ppc4xx) it should set decrementer_count to zero. 3412 timer_interrupt() calls timer_interrupt_cpu() for CPU 3413 specific handling. If board has watchdog / status_led 3414 / other_activity_monitor it works automatically from 3415 general timer_interrupt(). 3416 3417 3418Board initialization settings: 3419------------------------------ 3420 3421During Initialization u-boot calls a number of board specific functions 3422to allow the preparation of board specific prerequisites, e.g. pin setup 3423before drivers are initialized. To enable these callbacks the 3424following configuration macros have to be defined. Currently this is 3425architecture specific, so please check arch/your_architecture/lib/board.c 3426typically in board_init_f() and board_init_r(). 3427 3428- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f() 3429- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r() 3430- CONFIG_BOARD_LATE_INIT: Call board_late_init() 3431- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init() 3432 3433Configuration Settings: 3434----------------------- 3435 3436- CONFIG_SYS_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit. 3437 Optionally it can be defined to support 64-bit memory commands. 3438 3439- CONFIG_SYS_LONGHELP: Defined when you want long help messages included; 3440 undefine this when you're short of memory. 3441 3442- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default 3443 width of the commands listed in the 'help' command output. 3444 3445- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to 3446 prompt for user input. 3447 3448- CONFIG_SYS_CBSIZE: Buffer size for input from the Console 3449 3450- CONFIG_SYS_PBSIZE: Buffer size for Console output 3451 3452- CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands 3453 3454- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to 3455 the application (usually a Linux kernel) when it is 3456 booted 3457 3458- CONFIG_SYS_BAUDRATE_TABLE: 3459 List of legal baudrate settings for this board. 3460 3461- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END: 3462 Begin and End addresses of the area used by the 3463 simple memory test. 3464 3465- CONFIG_SYS_ALT_MEMTEST: 3466 Enable an alternate, more extensive memory test. 3467 3468- CONFIG_SYS_MEMTEST_SCRATCH: 3469 Scratch address used by the alternate memory test 3470 You only need to set this if address zero isn't writeable 3471 3472- CONFIG_SYS_MEM_RESERVE_SECURE 3473 Only implemented for ARMv8 for now. 3474 If defined, the size of CONFIG_SYS_MEM_RESERVE_SECURE memory 3475 is substracted from total RAM and won't be reported to OS. 3476 This memory can be used as secure memory. A variable 3477 gd->arch.secure_ram is used to track the location. In systems 3478 the RAM base is not zero, or RAM is divided into banks, 3479 this variable needs to be recalcuated to get the address. 3480 3481- CONFIG_SYS_MEM_TOP_HIDE: 3482 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header, 3483 this specified memory area will get subtracted from the top 3484 (end) of RAM and won't get "touched" at all by U-Boot. By 3485 fixing up gd->ram_size the Linux kernel should gets passed 3486 the now "corrected" memory size and won't touch it either. 3487 This should work for arch/ppc and arch/powerpc. Only Linux 3488 board ports in arch/powerpc with bootwrapper support that 3489 recalculate the memory size from the SDRAM controller setup 3490 will have to get fixed in Linux additionally. 3491 3492 This option can be used as a workaround for the 440EPx/GRx 3493 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't 3494 be touched. 3495 3496 WARNING: Please make sure that this value is a multiple of 3497 the Linux page size (normally 4k). If this is not the case, 3498 then the end address of the Linux memory will be located at a 3499 non page size aligned address and this could cause major 3500 problems. 3501 3502- CONFIG_SYS_LOADS_BAUD_CHANGE: 3503 Enable temporary baudrate change while serial download 3504 3505- CONFIG_SYS_SDRAM_BASE: 3506 Physical start address of SDRAM. _Must_ be 0 here. 3507 3508- CONFIG_SYS_FLASH_BASE: 3509 Physical start address of Flash memory. 3510 3511- CONFIG_SYS_MONITOR_BASE: 3512 Physical start address of boot monitor code (set by 3513 make config files to be same as the text base address 3514 (CONFIG_SYS_TEXT_BASE) used when linking) - same as 3515 CONFIG_SYS_FLASH_BASE when booting from flash. 3516 3517- CONFIG_SYS_MONITOR_LEN: 3518 Size of memory reserved for monitor code, used to 3519 determine _at_compile_time_ (!) if the environment is 3520 embedded within the U-Boot image, or in a separate 3521 flash sector. 3522 3523- CONFIG_SYS_MALLOC_LEN: 3524 Size of DRAM reserved for malloc() use. 3525 3526- CONFIG_SYS_MALLOC_F_LEN 3527 Size of the malloc() pool for use before relocation. If 3528 this is defined, then a very simple malloc() implementation 3529 will become available before relocation. The address is just 3530 below the global data, and the stack is moved down to make 3531 space. 3532 3533 This feature allocates regions with increasing addresses 3534 within the region. calloc() is supported, but realloc() 3535 is not available. free() is supported but does nothing. 3536 The memory will be freed (or in fact just forgotten) when 3537 U-Boot relocates itself. 3538 3539- CONFIG_SYS_MALLOC_SIMPLE 3540 Provides a simple and small malloc() and calloc() for those 3541 boards which do not use the full malloc in SPL (which is 3542 enabled with CONFIG_SYS_SPL_MALLOC_START). 3543 3544- CONFIG_SYS_NONCACHED_MEMORY: 3545 Size of non-cached memory area. This area of memory will be 3546 typically located right below the malloc() area and mapped 3547 uncached in the MMU. This is useful for drivers that would 3548 otherwise require a lot of explicit cache maintenance. For 3549 some drivers it's also impossible to properly maintain the 3550 cache. For example if the regions that need to be flushed 3551 are not a multiple of the cache-line size, *and* padding 3552 cannot be allocated between the regions to align them (i.e. 3553 if the HW requires a contiguous array of regions, and the 3554 size of each region is not cache-aligned), then a flush of 3555 one region may result in overwriting data that hardware has 3556 written to another region in the same cache-line. This can 3557 happen for example in network drivers where descriptors for 3558 buffers are typically smaller than the CPU cache-line (e.g. 3559 16 bytes vs. 32 or 64 bytes). 3560 3561 Non-cached memory is only supported on 32-bit ARM at present. 3562 3563- CONFIG_SYS_BOOTM_LEN: 3564 Normally compressed uImages are limited to an 3565 uncompressed size of 8 MBytes. If this is not enough, 3566 you can define CONFIG_SYS_BOOTM_LEN in your board config file 3567 to adjust this setting to your needs. 3568 3569- CONFIG_SYS_BOOTMAPSZ: 3570 Maximum size of memory mapped by the startup code of 3571 the Linux kernel; all data that must be processed by 3572 the Linux kernel (bd_info, boot arguments, FDT blob if 3573 used) must be put below this limit, unless "bootm_low" 3574 environment variable is defined and non-zero. In such case 3575 all data for the Linux kernel must be between "bootm_low" 3576 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment 3577 variable "bootm_mapsize" will override the value of 3578 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined, 3579 then the value in "bootm_size" will be used instead. 3580 3581- CONFIG_SYS_BOOT_RAMDISK_HIGH: 3582 Enable initrd_high functionality. If defined then the 3583 initrd_high feature is enabled and the bootm ramdisk subcommand 3584 is enabled. 3585 3586- CONFIG_SYS_BOOT_GET_CMDLINE: 3587 Enables allocating and saving kernel cmdline in space between 3588 "bootm_low" and "bootm_low" + BOOTMAPSZ. 3589 3590- CONFIG_SYS_BOOT_GET_KBD: 3591 Enables allocating and saving a kernel copy of the bd_info in 3592 space between "bootm_low" and "bootm_low" + BOOTMAPSZ. 3593 3594- CONFIG_SYS_MAX_FLASH_BANKS: 3595 Max number of Flash memory banks 3596 3597- CONFIG_SYS_MAX_FLASH_SECT: 3598 Max number of sectors on a Flash chip 3599 3600- CONFIG_SYS_FLASH_ERASE_TOUT: 3601 Timeout for Flash erase operations (in ms) 3602 3603- CONFIG_SYS_FLASH_WRITE_TOUT: 3604 Timeout for Flash write operations (in ms) 3605 3606- CONFIG_SYS_FLASH_LOCK_TOUT 3607 Timeout for Flash set sector lock bit operation (in ms) 3608 3609- CONFIG_SYS_FLASH_UNLOCK_TOUT 3610 Timeout for Flash clear lock bits operation (in ms) 3611 3612- CONFIG_SYS_FLASH_PROTECTION 3613 If defined, hardware flash sectors protection is used 3614 instead of U-Boot software protection. 3615 3616- CONFIG_SYS_DIRECT_FLASH_TFTP: 3617 3618 Enable TFTP transfers directly to flash memory; 3619 without this option such a download has to be 3620 performed in two steps: (1) download to RAM, and (2) 3621 copy from RAM to flash. 3622 3623 The two-step approach is usually more reliable, since 3624 you can check if the download worked before you erase 3625 the flash, but in some situations (when system RAM is 3626 too limited to allow for a temporary copy of the 3627 downloaded image) this option may be very useful. 3628 3629- CONFIG_SYS_FLASH_CFI: 3630 Define if the flash driver uses extra elements in the 3631 common flash structure for storing flash geometry. 3632 3633- CONFIG_FLASH_CFI_DRIVER 3634 This option also enables the building of the cfi_flash driver 3635 in the drivers directory 3636 3637- CONFIG_FLASH_CFI_MTD 3638 This option enables the building of the cfi_mtd driver 3639 in the drivers directory. The driver exports CFI flash 3640 to the MTD layer. 3641 3642- CONFIG_SYS_FLASH_USE_BUFFER_WRITE 3643 Use buffered writes to flash. 3644 3645- CONFIG_FLASH_SPANSION_S29WS_N 3646 s29ws-n MirrorBit flash has non-standard addresses for buffered 3647 write commands. 3648 3649- CONFIG_SYS_FLASH_QUIET_TEST 3650 If this option is defined, the common CFI flash doesn't 3651 print it's warning upon not recognized FLASH banks. This 3652 is useful, if some of the configured banks are only 3653 optionally available. 3654 3655- CONFIG_FLASH_SHOW_PROGRESS 3656 If defined (must be an integer), print out countdown 3657 digits and dots. Recommended value: 45 (9..1) for 80 3658 column displays, 15 (3..1) for 40 column displays. 3659 3660- CONFIG_FLASH_VERIFY 3661 If defined, the content of the flash (destination) is compared 3662 against the source after the write operation. An error message 3663 will be printed when the contents are not identical. 3664 Please note that this option is useless in nearly all cases, 3665 since such flash programming errors usually are detected earlier 3666 while unprotecting/erasing/programming. Please only enable 3667 this option if you really know what you are doing. 3668 3669- CONFIG_SYS_RX_ETH_BUFFER: 3670 Defines the number of Ethernet receive buffers. On some 3671 Ethernet controllers it is recommended to set this value 3672 to 8 or even higher (EEPRO100 or 405 EMAC), since all 3673 buffers can be full shortly after enabling the interface 3674 on high Ethernet traffic. 3675 Defaults to 4 if not defined. 3676 3677- CONFIG_ENV_MAX_ENTRIES 3678 3679 Maximum number of entries in the hash table that is used 3680 internally to store the environment settings. The default 3681 setting is supposed to be generous and should work in most 3682 cases. This setting can be used to tune behaviour; see 3683 lib/hashtable.c for details. 3684 3685- CONFIG_ENV_FLAGS_LIST_DEFAULT 3686- CONFIG_ENV_FLAGS_LIST_STATIC 3687 Enable validation of the values given to environment variables when 3688 calling env set. Variables can be restricted to only decimal, 3689 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined, 3690 the variables can also be restricted to IP address or MAC address. 3691 3692 The format of the list is: 3693 type_attribute = [s|d|x|b|i|m] 3694 access_attribute = [a|r|o|c] 3695 attributes = type_attribute[access_attribute] 3696 entry = variable_name[:attributes] 3697 list = entry[,list] 3698 3699 The type attributes are: 3700 s - String (default) 3701 d - Decimal 3702 x - Hexadecimal 3703 b - Boolean ([1yYtT|0nNfF]) 3704 i - IP address 3705 m - MAC address 3706 3707 The access attributes are: 3708 a - Any (default) 3709 r - Read-only 3710 o - Write-once 3711 c - Change-default 3712 3713 - CONFIG_ENV_FLAGS_LIST_DEFAULT 3714 Define this to a list (string) to define the ".flags" 3715 environment variable in the default or embedded environment. 3716 3717 - CONFIG_ENV_FLAGS_LIST_STATIC 3718 Define this to a list (string) to define validation that 3719 should be done if an entry is not found in the ".flags" 3720 environment variable. To override a setting in the static 3721 list, simply add an entry for the same variable name to the 3722 ".flags" variable. 3723 3724 If CONFIG_REGEX is defined, the variable_name above is evaluated as a 3725 regular expression. This allows multiple variables to define the same 3726 flags without explicitly listing them for each variable. 3727 3728- CONFIG_ENV_ACCESS_IGNORE_FORCE 3729 If defined, don't allow the -f switch to env set override variable 3730 access flags. 3731 3732- CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC (OMAP only) 3733 This is set by OMAP boards for the max time that reset should 3734 be asserted. See doc/README.omap-reset-time for details on how 3735 the value can be calculated on a given board. 3736 3737- CONFIG_USE_STDINT 3738 If stdint.h is available with your toolchain you can define this 3739 option to enable it. You can provide option 'USE_STDINT=1' when 3740 building U-Boot to enable this. 3741 3742The following definitions that deal with the placement and management 3743of environment data (variable area); in general, we support the 3744following configurations: 3745 3746- CONFIG_BUILD_ENVCRC: 3747 3748 Builds up envcrc with the target environment so that external utils 3749 may easily extract it and embed it in final U-Boot images. 3750 3751- CONFIG_ENV_IS_IN_FLASH: 3752 3753 Define this if the environment is in flash memory. 3754 3755 a) The environment occupies one whole flash sector, which is 3756 "embedded" in the text segment with the U-Boot code. This 3757 happens usually with "bottom boot sector" or "top boot 3758 sector" type flash chips, which have several smaller 3759 sectors at the start or the end. For instance, such a 3760 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In 3761 such a case you would place the environment in one of the 3762 4 kB sectors - with U-Boot code before and after it. With 3763 "top boot sector" type flash chips, you would put the 3764 environment in one of the last sectors, leaving a gap 3765 between U-Boot and the environment. 3766 3767 - CONFIG_ENV_OFFSET: 3768 3769 Offset of environment data (variable area) to the 3770 beginning of flash memory; for instance, with bottom boot 3771 type flash chips the second sector can be used: the offset 3772 for this sector is given here. 3773 3774 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE. 3775 3776 - CONFIG_ENV_ADDR: 3777 3778 This is just another way to specify the start address of 3779 the flash sector containing the environment (instead of 3780 CONFIG_ENV_OFFSET). 3781 3782 - CONFIG_ENV_SECT_SIZE: 3783 3784 Size of the sector containing the environment. 3785 3786 3787 b) Sometimes flash chips have few, equal sized, BIG sectors. 3788 In such a case you don't want to spend a whole sector for 3789 the environment. 3790 3791 - CONFIG_ENV_SIZE: 3792 3793 If you use this in combination with CONFIG_ENV_IS_IN_FLASH 3794 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part 3795 of this flash sector for the environment. This saves 3796 memory for the RAM copy of the environment. 3797 3798 It may also save flash memory if you decide to use this 3799 when your environment is "embedded" within U-Boot code, 3800 since then the remainder of the flash sector could be used 3801 for U-Boot code. It should be pointed out that this is 3802 STRONGLY DISCOURAGED from a robustness point of view: 3803 updating the environment in flash makes it always 3804 necessary to erase the WHOLE sector. If something goes 3805 wrong before the contents has been restored from a copy in 3806 RAM, your target system will be dead. 3807 3808 - CONFIG_ENV_ADDR_REDUND 3809 CONFIG_ENV_SIZE_REDUND 3810 3811 These settings describe a second storage area used to hold 3812 a redundant copy of the environment data, so that there is 3813 a valid backup copy in case there is a power failure during 3814 a "saveenv" operation. 3815 3816BE CAREFUL! Any changes to the flash layout, and some changes to the 3817source code will make it necessary to adapt <board>/u-boot.lds* 3818accordingly! 3819 3820 3821- CONFIG_ENV_IS_IN_NVRAM: 3822 3823 Define this if you have some non-volatile memory device 3824 (NVRAM, battery buffered SRAM) which you want to use for the 3825 environment. 3826 3827 - CONFIG_ENV_ADDR: 3828 - CONFIG_ENV_SIZE: 3829 3830 These two #defines are used to determine the memory area you 3831 want to use for environment. It is assumed that this memory 3832 can just be read and written to, without any special 3833 provision. 3834 3835BE CAREFUL! The first access to the environment happens quite early 3836in U-Boot initialization (when we try to get the setting of for the 3837console baudrate). You *MUST* have mapped your NVRAM area then, or 3838U-Boot will hang. 3839 3840Please note that even with NVRAM we still use a copy of the 3841environment in RAM: we could work on NVRAM directly, but we want to 3842keep settings there always unmodified except somebody uses "saveenv" 3843to save the current settings. 3844 3845 3846- CONFIG_ENV_IS_IN_EEPROM: 3847 3848 Use this if you have an EEPROM or similar serial access 3849 device and a driver for it. 3850 3851 - CONFIG_ENV_OFFSET: 3852 - CONFIG_ENV_SIZE: 3853 3854 These two #defines specify the offset and size of the 3855 environment area within the total memory of your EEPROM. 3856 3857 - CONFIG_SYS_I2C_EEPROM_ADDR: 3858 If defined, specified the chip address of the EEPROM device. 3859 The default address is zero. 3860 3861 - CONFIG_SYS_I2C_EEPROM_BUS: 3862 If defined, specified the i2c bus of the EEPROM device. 3863 3864 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS: 3865 If defined, the number of bits used to address bytes in a 3866 single page in the EEPROM device. A 64 byte page, for example 3867 would require six bits. 3868 3869 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS: 3870 If defined, the number of milliseconds to delay between 3871 page writes. The default is zero milliseconds. 3872 3873 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN: 3874 The length in bytes of the EEPROM memory array address. Note 3875 that this is NOT the chip address length! 3876 3877 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW: 3878 EEPROM chips that implement "address overflow" are ones 3879 like Catalyst 24WC04/08/16 which has 9/10/11 bits of 3880 address and the extra bits end up in the "chip address" bit 3881 slots. This makes a 24WC08 (1Kbyte) chip look like four 256 3882 byte chips. 3883 3884 Note that we consider the length of the address field to 3885 still be one byte because the extra address bits are hidden 3886 in the chip address. 3887 3888 - CONFIG_SYS_EEPROM_SIZE: 3889 The size in bytes of the EEPROM device. 3890 3891 - CONFIG_ENV_EEPROM_IS_ON_I2C 3892 define this, if you have I2C and SPI activated, and your 3893 EEPROM, which holds the environment, is on the I2C bus. 3894 3895 - CONFIG_I2C_ENV_EEPROM_BUS 3896 if you have an Environment on an EEPROM reached over 3897 I2C muxes, you can define here, how to reach this 3898 EEPROM. For example: 3899 3900 #define CONFIG_I2C_ENV_EEPROM_BUS 1 3901 3902 EEPROM which holds the environment, is reached over 3903 a pca9547 i2c mux with address 0x70, channel 3. 3904 3905- CONFIG_ENV_IS_IN_DATAFLASH: 3906 3907 Define this if you have a DataFlash memory device which you 3908 want to use for the environment. 3909 3910 - CONFIG_ENV_OFFSET: 3911 - CONFIG_ENV_ADDR: 3912 - CONFIG_ENV_SIZE: 3913 3914 These three #defines specify the offset and size of the 3915 environment area within the total memory of your DataFlash placed 3916 at the specified address. 3917 3918- CONFIG_ENV_IS_IN_SPI_FLASH: 3919 3920 Define this if you have a SPI Flash memory device which you 3921 want to use for the environment. 3922 3923 - CONFIG_ENV_OFFSET: 3924 - CONFIG_ENV_SIZE: 3925 3926 These two #defines specify the offset and size of the 3927 environment area within the SPI Flash. CONFIG_ENV_OFFSET must be 3928 aligned to an erase sector boundary. 3929 3930 - CONFIG_ENV_SECT_SIZE: 3931 3932 Define the SPI flash's sector size. 3933 3934 - CONFIG_ENV_OFFSET_REDUND (optional): 3935 3936 This setting describes a second storage area of CONFIG_ENV_SIZE 3937 size used to hold a redundant copy of the environment data, so 3938 that there is a valid backup copy in case there is a power failure 3939 during a "saveenv" operation. CONFIG_ENV_OFFSET_REDUND must be 3940 aligned to an erase sector boundary. 3941 3942 - CONFIG_ENV_SPI_BUS (optional): 3943 - CONFIG_ENV_SPI_CS (optional): 3944 3945 Define the SPI bus and chip select. If not defined they will be 0. 3946 3947 - CONFIG_ENV_SPI_MAX_HZ (optional): 3948 3949 Define the SPI max work clock. If not defined then use 1MHz. 3950 3951 - CONFIG_ENV_SPI_MODE (optional): 3952 3953 Define the SPI work mode. If not defined then use SPI_MODE_3. 3954 3955- CONFIG_ENV_IS_IN_REMOTE: 3956 3957 Define this if you have a remote memory space which you 3958 want to use for the local device's environment. 3959 3960 - CONFIG_ENV_ADDR: 3961 - CONFIG_ENV_SIZE: 3962 3963 These two #defines specify the address and size of the 3964 environment area within the remote memory space. The 3965 local device can get the environment from remote memory 3966 space by SRIO or PCIE links. 3967 3968BE CAREFUL! For some special cases, the local device can not use 3969"saveenv" command. For example, the local device will get the 3970environment stored in a remote NOR flash by SRIO or PCIE link, 3971but it can not erase, write this NOR flash by SRIO or PCIE interface. 3972 3973- CONFIG_ENV_IS_IN_NAND: 3974 3975 Define this if you have a NAND device which you want to use 3976 for the environment. 3977 3978 - CONFIG_ENV_OFFSET: 3979 - CONFIG_ENV_SIZE: 3980 3981 These two #defines specify the offset and size of the environment 3982 area within the first NAND device. CONFIG_ENV_OFFSET must be 3983 aligned to an erase block boundary. 3984 3985 - CONFIG_ENV_OFFSET_REDUND (optional): 3986 3987 This setting describes a second storage area of CONFIG_ENV_SIZE 3988 size used to hold a redundant copy of the environment data, so 3989 that there is a valid backup copy in case there is a power failure 3990 during a "saveenv" operation. CONFIG_ENV_OFFSET_REDUND must be 3991 aligned to an erase block boundary. 3992 3993 - CONFIG_ENV_RANGE (optional): 3994 3995 Specifies the length of the region in which the environment 3996 can be written. This should be a multiple of the NAND device's 3997 block size. Specifying a range with more erase blocks than 3998 are needed to hold CONFIG_ENV_SIZE allows bad blocks within 3999 the range to be avoided. 4000 4001 - CONFIG_ENV_OFFSET_OOB (optional): 4002 4003 Enables support for dynamically retrieving the offset of the 4004 environment from block zero's out-of-band data. The 4005 "nand env.oob" command can be used to record this offset. 4006 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when 4007 using CONFIG_ENV_OFFSET_OOB. 4008 4009- CONFIG_NAND_ENV_DST 4010 4011 Defines address in RAM to which the nand_spl code should copy the 4012 environment. If redundant environment is used, it will be copied to 4013 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE. 4014 4015- CONFIG_ENV_IS_IN_UBI: 4016 4017 Define this if you have an UBI volume that you want to use for the 4018 environment. This has the benefit of wear-leveling the environment 4019 accesses, which is important on NAND. 4020 4021 - CONFIG_ENV_UBI_PART: 4022 4023 Define this to a string that is the mtd partition containing the UBI. 4024 4025 - CONFIG_ENV_UBI_VOLUME: 4026 4027 Define this to the name of the volume that you want to store the 4028 environment in. 4029 4030 - CONFIG_ENV_UBI_VOLUME_REDUND: 4031 4032 Define this to the name of another volume to store a second copy of 4033 the environment in. This will enable redundant environments in UBI. 4034 It is assumed that both volumes are in the same MTD partition. 4035 4036 - CONFIG_UBI_SILENCE_MSG 4037 - CONFIG_UBIFS_SILENCE_MSG 4038 4039 You will probably want to define these to avoid a really noisy system 4040 when storing the env in UBI. 4041 4042- CONFIG_ENV_IS_IN_FAT: 4043 Define this if you want to use the FAT file system for the environment. 4044 4045 - FAT_ENV_INTERFACE: 4046 4047 Define this to a string that is the name of the block device. 4048 4049 - FAT_ENV_DEVICE_AND_PART: 4050 4051 Define this to a string to specify the partition of the device. It can 4052 be as following: 4053 4054 "D:P", "D:0", "D", "D:" or "D:auto" (D, P are integers. And P >= 1) 4055 - "D:P": device D partition P. Error occurs if device D has no 4056 partition table. 4057 - "D:0": device D. 4058 - "D" or "D:": device D partition 1 if device D has partition 4059 table, or the whole device D if has no partition 4060 table. 4061 - "D:auto": first partition in device D with bootable flag set. 4062 If none, first valid partition in device D. If no 4063 partition table then means device D. 4064 4065 - FAT_ENV_FILE: 4066 4067 It's a string of the FAT file name. This file use to store the 4068 environment. 4069 4070 - CONFIG_FAT_WRITE: 4071 This should be defined. Otherwise it cannot save the environment file. 4072 4073- CONFIG_ENV_IS_IN_MMC: 4074 4075 Define this if you have an MMC device which you want to use for the 4076 environment. 4077 4078 - CONFIG_SYS_MMC_ENV_DEV: 4079 4080 Specifies which MMC device the environment is stored in. 4081 4082 - CONFIG_SYS_MMC_ENV_PART (optional): 4083 4084 Specifies which MMC partition the environment is stored in. If not 4085 set, defaults to partition 0, the user area. Common values might be 4086 1 (first MMC boot partition), 2 (second MMC boot partition). 4087 4088 - CONFIG_ENV_OFFSET: 4089 - CONFIG_ENV_SIZE: 4090 4091 These two #defines specify the offset and size of the environment 4092 area within the specified MMC device. 4093 4094 If offset is positive (the usual case), it is treated as relative to 4095 the start of the MMC partition. If offset is negative, it is treated 4096 as relative to the end of the MMC partition. This can be useful if 4097 your board may be fitted with different MMC devices, which have 4098 different sizes for the MMC partitions, and you always want the 4099 environment placed at the very end of the partition, to leave the 4100 maximum possible space before it, to store other data. 4101 4102 These two values are in units of bytes, but must be aligned to an 4103 MMC sector boundary. 4104 4105 - CONFIG_ENV_OFFSET_REDUND (optional): 4106 4107 Specifies a second storage area, of CONFIG_ENV_SIZE size, used to 4108 hold a redundant copy of the environment data. This provides a 4109 valid backup copy in case the other copy is corrupted, e.g. due 4110 to a power failure during a "saveenv" operation. 4111 4112 This value may also be positive or negative; this is handled in the 4113 same way as CONFIG_ENV_OFFSET. 4114 4115 This value is also in units of bytes, but must also be aligned to 4116 an MMC sector boundary. 4117 4118 - CONFIG_ENV_SIZE_REDUND (optional): 4119 4120 This value need not be set, even when CONFIG_ENV_OFFSET_REDUND is 4121 set. If this value is set, it must be set to the same value as 4122 CONFIG_ENV_SIZE. 4123 4124- CONFIG_SYS_SPI_INIT_OFFSET 4125 4126 Defines offset to the initial SPI buffer area in DPRAM. The 4127 area is used at an early stage (ROM part) if the environment 4128 is configured to reside in the SPI EEPROM: We need a 520 byte 4129 scratch DPRAM area. It is used between the two initialization 4130 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems 4131 to be a good choice since it makes it far enough from the 4132 start of the data area as well as from the stack pointer. 4133 4134Please note that the environment is read-only until the monitor 4135has been relocated to RAM and a RAM copy of the environment has been 4136created; also, when using EEPROM you will have to use getenv_f() 4137until then to read environment variables. 4138 4139The environment is protected by a CRC32 checksum. Before the monitor 4140is relocated into RAM, as a result of a bad CRC you will be working 4141with the compiled-in default environment - *silently*!!! [This is 4142necessary, because the first environment variable we need is the 4143"baudrate" setting for the console - if we have a bad CRC, we don't 4144have any device yet where we could complain.] 4145 4146Note: once the monitor has been relocated, then it will complain if 4147the default environment is used; a new CRC is computed as soon as you 4148use the "saveenv" command to store a valid environment. 4149 4150- CONFIG_SYS_FAULT_ECHO_LINK_DOWN: 4151 Echo the inverted Ethernet link state to the fault LED. 4152 4153 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR 4154 also needs to be defined. 4155 4156- CONFIG_SYS_FAULT_MII_ADDR: 4157 MII address of the PHY to check for the Ethernet link state. 4158 4159- CONFIG_NS16550_MIN_FUNCTIONS: 4160 Define this if you desire to only have use of the NS16550_init 4161 and NS16550_putc functions for the serial driver located at 4162 drivers/serial/ns16550.c. This option is useful for saving 4163 space for already greatly restricted images, including but not 4164 limited to NAND_SPL configurations. 4165 4166- CONFIG_DISPLAY_BOARDINFO 4167 Display information about the board that U-Boot is running on 4168 when U-Boot starts up. The board function checkboard() is called 4169 to do this. 4170 4171- CONFIG_DISPLAY_BOARDINFO_LATE 4172 Similar to the previous option, but display this information 4173 later, once stdio is running and output goes to the LCD, if 4174 present. 4175 4176- CONFIG_BOARD_SIZE_LIMIT: 4177 Maximum size of the U-Boot image. When defined, the 4178 build system checks that the actual size does not 4179 exceed it. 4180 4181Low Level (hardware related) configuration options: 4182--------------------------------------------------- 4183 4184- CONFIG_SYS_CACHELINE_SIZE: 4185 Cache Line Size of the CPU. 4186 4187- CONFIG_SYS_DEFAULT_IMMR: 4188 Default address of the IMMR after system reset. 4189 4190 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU, 4191 and RPXsuper) to be able to adjust the position of 4192 the IMMR register after a reset. 4193 4194- CONFIG_SYS_CCSRBAR_DEFAULT: 4195 Default (power-on reset) physical address of CCSR on Freescale 4196 PowerPC SOCs. 4197 4198- CONFIG_SYS_CCSRBAR: 4199 Virtual address of CCSR. On a 32-bit build, this is typically 4200 the same value as CONFIG_SYS_CCSRBAR_DEFAULT. 4201 4202 CONFIG_SYS_DEFAULT_IMMR must also be set to this value, 4203 for cross-platform code that uses that macro instead. 4204 4205- CONFIG_SYS_CCSRBAR_PHYS: 4206 Physical address of CCSR. CCSR can be relocated to a new 4207 physical address, if desired. In this case, this macro should 4208 be set to that address. Otherwise, it should be set to the 4209 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR 4210 is typically relocated on 36-bit builds. It is recommended 4211 that this macro be defined via the _HIGH and _LOW macros: 4212 4213 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH 4214 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW) 4215 4216- CONFIG_SYS_CCSRBAR_PHYS_HIGH: 4217 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically 4218 either 0 (32-bit build) or 0xF (36-bit build). This macro is 4219 used in assembly code, so it must not contain typecasts or 4220 integer size suffixes (e.g. "ULL"). 4221 4222- CONFIG_SYS_CCSRBAR_PHYS_LOW: 4223 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is 4224 used in assembly code, so it must not contain typecasts or 4225 integer size suffixes (e.g. "ULL"). 4226 4227- CONFIG_SYS_CCSR_DO_NOT_RELOCATE: 4228 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be 4229 forced to a value that ensures that CCSR is not relocated. 4230 4231- Floppy Disk Support: 4232 CONFIG_SYS_FDC_DRIVE_NUMBER 4233 4234 the default drive number (default value 0) 4235 4236 CONFIG_SYS_ISA_IO_STRIDE 4237 4238 defines the spacing between FDC chipset registers 4239 (default value 1) 4240 4241 CONFIG_SYS_ISA_IO_OFFSET 4242 4243 defines the offset of register from address. It 4244 depends on which part of the data bus is connected to 4245 the FDC chipset. (default value 0) 4246 4247 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and 4248 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their 4249 default value. 4250 4251 if CONFIG_SYS_FDC_HW_INIT is defined, then the function 4252 fdc_hw_init() is called at the beginning of the FDC 4253 setup. fdc_hw_init() must be provided by the board 4254 source code. It is used to make hardware-dependent 4255 initializations. 4256 4257- CONFIG_IDE_AHB: 4258 Most IDE controllers were designed to be connected with PCI 4259 interface. Only few of them were designed for AHB interface. 4260 When software is doing ATA command and data transfer to 4261 IDE devices through IDE-AHB controller, some additional 4262 registers accessing to these kind of IDE-AHB controller 4263 is required. 4264 4265- CONFIG_SYS_IMMR: Physical address of the Internal Memory. 4266 DO NOT CHANGE unless you know exactly what you're 4267 doing! (11-4) [MPC8xx/82xx systems only] 4268 4269- CONFIG_SYS_INIT_RAM_ADDR: 4270 4271 Start address of memory area that can be used for 4272 initial data and stack; please note that this must be 4273 writable memory that is working WITHOUT special 4274 initialization, i. e. you CANNOT use normal RAM which 4275 will become available only after programming the 4276 memory controller and running certain initialization 4277 sequences. 4278 4279 U-Boot uses the following memory types: 4280 - MPC8xx and MPC8260: IMMR (internal memory of the CPU) 4281 - MPC824X: data cache 4282 - PPC4xx: data cache 4283 4284- CONFIG_SYS_GBL_DATA_OFFSET: 4285 4286 Offset of the initial data structure in the memory 4287 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually 4288 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial 4289 data is located at the end of the available space 4290 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE - 4291 GENERATED_GBL_DATA_SIZE), and the initial stack is just 4292 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR + 4293 CONFIG_SYS_GBL_DATA_OFFSET) downward. 4294 4295 Note: 4296 On the MPC824X (or other systems that use the data 4297 cache for initial memory) the address chosen for 4298 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must 4299 point to an otherwise UNUSED address space between 4300 the top of RAM and the start of the PCI space. 4301 4302- CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6) 4303 4304- CONFIG_SYS_SYPCR: System Protection Control (11-9) 4305 4306- CONFIG_SYS_TBSCR: Time Base Status and Control (11-26) 4307 4308- CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31) 4309 4310- CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30) 4311 4312- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27) 4313 4314- CONFIG_SYS_OR_TIMING_SDRAM: 4315 SDRAM timing 4316 4317- CONFIG_SYS_MAMR_PTA: 4318 periodic timer for refresh 4319 4320- CONFIG_SYS_DER: Debug Event Register (37-47) 4321 4322- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM, 4323 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP, 4324 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM, 4325 CONFIG_SYS_BR1_PRELIM: 4326 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 4327 4328- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 4329 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM, 4330 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM: 4331 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 4332 4333- CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K, 4334 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL: 4335 Machine Mode Register and Memory Periodic Timer 4336 Prescaler definitions (SDRAM timing) 4337 4338- CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]: 4339 enable I2C microcode relocation patch (MPC8xx); 4340 define relocation offset in DPRAM [DSP2] 4341 4342- CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]: 4343 enable SMC microcode relocation patch (MPC8xx); 4344 define relocation offset in DPRAM [SMC1] 4345 4346- CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]: 4347 enable SPI microcode relocation patch (MPC8xx); 4348 define relocation offset in DPRAM [SCC4] 4349 4350- CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only) 4351 Offset of the bootmode word in DPRAM used by post 4352 (Power On Self Tests). This definition overrides 4353 #define'd default value in commproc.h resp. 4354 cpm_8260.h. 4355 4356- CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB, 4357 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL, 4358 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS, 4359 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB, 4360 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START, 4361 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL, 4362 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE, 4363 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only) 4364 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set. 4365 4366- CONFIG_PCI_DISABLE_PCIE: 4367 Disable PCI-Express on systems where it is supported but not 4368 required. 4369 4370- CONFIG_PCI_ENUM_ONLY 4371 Only scan through and get the devices on the buses. 4372 Don't do any setup work, presumably because someone or 4373 something has already done it, and we don't need to do it 4374 a second time. Useful for platforms that are pre-booted 4375 by coreboot or similar. 4376 4377- CONFIG_PCI_INDIRECT_BRIDGE: 4378 Enable support for indirect PCI bridges. 4379 4380- CONFIG_SYS_SRIO: 4381 Chip has SRIO or not 4382 4383- CONFIG_SRIO1: 4384 Board has SRIO 1 port available 4385 4386- CONFIG_SRIO2: 4387 Board has SRIO 2 port available 4388 4389- CONFIG_SRIO_PCIE_BOOT_MASTER 4390 Board can support master function for Boot from SRIO and PCIE 4391 4392- CONFIG_SYS_SRIOn_MEM_VIRT: 4393 Virtual Address of SRIO port 'n' memory region 4394 4395- CONFIG_SYS_SRIOn_MEM_PHYS: 4396 Physical Address of SRIO port 'n' memory region 4397 4398- CONFIG_SYS_SRIOn_MEM_SIZE: 4399 Size of SRIO port 'n' memory region 4400 4401- CONFIG_SYS_NAND_BUSWIDTH_16BIT 4402 Defined to tell the NAND controller that the NAND chip is using 4403 a 16 bit bus. 4404 Not all NAND drivers use this symbol. 4405 Example of drivers that use it: 4406 - drivers/mtd/nand/ndfc.c 4407 - drivers/mtd/nand/mxc_nand.c 4408 4409- CONFIG_SYS_NDFC_EBC0_CFG 4410 Sets the EBC0_CFG register for the NDFC. If not defined 4411 a default value will be used. 4412 4413- CONFIG_SPD_EEPROM 4414 Get DDR timing information from an I2C EEPROM. Common 4415 with pluggable memory modules such as SODIMMs 4416 4417 SPD_EEPROM_ADDRESS 4418 I2C address of the SPD EEPROM 4419 4420- CONFIG_SYS_SPD_BUS_NUM 4421 If SPD EEPROM is on an I2C bus other than the first 4422 one, specify here. Note that the value must resolve 4423 to something your driver can deal with. 4424 4425- CONFIG_SYS_DDR_RAW_TIMING 4426 Get DDR timing information from other than SPD. Common with 4427 soldered DDR chips onboard without SPD. DDR raw timing 4428 parameters are extracted from datasheet and hard-coded into 4429 header files or board specific files. 4430 4431- CONFIG_FSL_DDR_INTERACTIVE 4432 Enable interactive DDR debugging. See doc/README.fsl-ddr. 4433 4434- CONFIG_FSL_DDR_SYNC_REFRESH 4435 Enable sync of refresh for multiple controllers. 4436 4437- CONFIG_FSL_DDR_BIST 4438 Enable built-in memory test for Freescale DDR controllers. 4439 4440- CONFIG_SYS_83XX_DDR_USES_CS0 4441 Only for 83xx systems. If specified, then DDR should 4442 be configured using CS0 and CS1 instead of CS2 and CS3. 4443 4444- CONFIG_ETHER_ON_FEC[12] 4445 Define to enable FEC[12] on a 8xx series processor. 4446 4447- CONFIG_FEC[12]_PHY 4448 Define to the hardcoded PHY address which corresponds 4449 to the given FEC; i. e. 4450 #define CONFIG_FEC1_PHY 4 4451 means that the PHY with address 4 is connected to FEC1 4452 4453 When set to -1, means to probe for first available. 4454 4455- CONFIG_FEC[12]_PHY_NORXERR 4456 The PHY does not have a RXERR line (RMII only). 4457 (so program the FEC to ignore it). 4458 4459- CONFIG_RMII 4460 Enable RMII mode for all FECs. 4461 Note that this is a global option, we can't 4462 have one FEC in standard MII mode and another in RMII mode. 4463 4464- CONFIG_CRC32_VERIFY 4465 Add a verify option to the crc32 command. 4466 The syntax is: 4467 4468 => crc32 -v <address> <count> <crc32> 4469 4470 Where address/count indicate a memory area 4471 and crc32 is the correct crc32 which the 4472 area should have. 4473 4474- CONFIG_LOOPW 4475 Add the "loopw" memory command. This only takes effect if 4476 the memory commands are activated globally (CONFIG_CMD_MEM). 4477 4478- CONFIG_MX_CYCLIC 4479 Add the "mdc" and "mwc" memory commands. These are cyclic 4480 "md/mw" commands. 4481 Examples: 4482 4483 => mdc.b 10 4 500 4484 This command will print 4 bytes (10,11,12,13) each 500 ms. 4485 4486 => mwc.l 100 12345678 10 4487 This command will write 12345678 to address 100 all 10 ms. 4488 4489 This only takes effect if the memory commands are activated 4490 globally (CONFIG_CMD_MEM). 4491 4492- CONFIG_SKIP_LOWLEVEL_INIT 4493 [ARM, NDS32, MIPS only] If this variable is defined, then certain 4494 low level initializations (like setting up the memory 4495 controller) are omitted and/or U-Boot does not 4496 relocate itself into RAM. 4497 4498 Normally this variable MUST NOT be defined. The only 4499 exception is when U-Boot is loaded (to RAM) by some 4500 other boot loader or by a debugger which performs 4501 these initializations itself. 4502 4503- CONFIG_SKIP_LOWLEVEL_INIT_ONLY 4504 [ARM926EJ-S only] This allows just the call to lowlevel_init() 4505 to be skipped. The normal CP15 init (such as enabling the 4506 instruction cache) is still performed. 4507 4508- CONFIG_SPL_BUILD 4509 Modifies the behaviour of start.S when compiling a loader 4510 that is executed before the actual U-Boot. E.g. when 4511 compiling a NAND SPL. 4512 4513- CONFIG_TPL_BUILD 4514 Modifies the behaviour of start.S when compiling a loader 4515 that is executed after the SPL and before the actual U-Boot. 4516 It is loaded by the SPL. 4517 4518- CONFIG_SYS_MPC85XX_NO_RESETVEC 4519 Only for 85xx systems. If this variable is specified, the section 4520 .resetvec is not kept and the section .bootpg is placed in the 4521 previous 4k of the .text section. 4522 4523- CONFIG_ARCH_MAP_SYSMEM 4524 Generally U-Boot (and in particular the md command) uses 4525 effective address. It is therefore not necessary to regard 4526 U-Boot address as virtual addresses that need to be translated 4527 to physical addresses. However, sandbox requires this, since 4528 it maintains its own little RAM buffer which contains all 4529 addressable memory. This option causes some memory accesses 4530 to be mapped through map_sysmem() / unmap_sysmem(). 4531 4532- CONFIG_X86_RESET_VECTOR 4533 If defined, the x86 reset vector code is included. This is not 4534 needed when U-Boot is running from Coreboot. 4535 4536- CONFIG_SYS_MPUCLK 4537 Defines the MPU clock speed (in MHz). 4538 4539 NOTE : currently only supported on AM335x platforms. 4540 4541- CONFIG_SPL_AM33XX_ENABLE_RTC32K_OSC: 4542 Enables the RTC32K OSC on AM33xx based plattforms 4543 4544- CONFIG_SYS_NAND_NO_SUBPAGE_WRITE 4545 Option to disable subpage write in NAND driver 4546 driver that uses this: 4547 drivers/mtd/nand/davinci_nand.c 4548 4549Freescale QE/FMAN Firmware Support: 4550----------------------------------- 4551 4552The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the 4553loading of "firmware", which is encoded in the QE firmware binary format. 4554This firmware often needs to be loaded during U-Boot booting, so macros 4555are used to identify the storage device (NOR flash, SPI, etc) and the address 4556within that device. 4557 4558- CONFIG_SYS_FMAN_FW_ADDR 4559 The address in the storage device where the FMAN microcode is located. The 4560 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 4561 is also specified. 4562 4563- CONFIG_SYS_QE_FW_ADDR 4564 The address in the storage device where the QE microcode is located. The 4565 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 4566 is also specified. 4567 4568- CONFIG_SYS_QE_FMAN_FW_LENGTH 4569 The maximum possible size of the firmware. The firmware binary format 4570 has a field that specifies the actual size of the firmware, but it 4571 might not be possible to read any part of the firmware unless some 4572 local storage is allocated to hold the entire firmware first. 4573 4574- CONFIG_SYS_QE_FMAN_FW_IN_NOR 4575 Specifies that QE/FMAN firmware is located in NOR flash, mapped as 4576 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the 4577 virtual address in NOR flash. 4578 4579- CONFIG_SYS_QE_FMAN_FW_IN_NAND 4580 Specifies that QE/FMAN firmware is located in NAND flash. 4581 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash. 4582 4583- CONFIG_SYS_QE_FMAN_FW_IN_MMC 4584 Specifies that QE/FMAN firmware is located on the primary SD/MMC 4585 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 4586 4587- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE 4588 Specifies that QE/FMAN firmware is located in the remote (master) 4589 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which 4590 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound 4591 window->master inbound window->master LAW->the ucode address in 4592 master's memory space. 4593 4594Freescale Layerscape Management Complex Firmware Support: 4595--------------------------------------------------------- 4596The Freescale Layerscape Management Complex (MC) supports the loading of 4597"firmware". 4598This firmware often needs to be loaded during U-Boot booting, so macros 4599are used to identify the storage device (NOR flash, SPI, etc) and the address 4600within that device. 4601 4602- CONFIG_FSL_MC_ENET 4603 Enable the MC driver for Layerscape SoCs. 4604 4605Freescale Layerscape Debug Server Support: 4606------------------------------------------- 4607The Freescale Layerscape Debug Server Support supports the loading of 4608"Debug Server firmware" and triggering SP boot-rom. 4609This firmware often needs to be loaded during U-Boot booting. 4610 4611- CONFIG_SYS_MC_RSV_MEM_ALIGN 4612 Define alignment of reserved memory MC requires 4613 4614Reproducible builds 4615------------------- 4616 4617In order to achieve reproducible builds, timestamps used in the U-Boot build 4618process have to be set to a fixed value. 4619 4620This is done using the SOURCE_DATE_EPOCH environment variable. 4621SOURCE_DATE_EPOCH is to be set on the build host's shell, not as a configuration 4622option for U-Boot or an environment variable in U-Boot. 4623 4624SOURCE_DATE_EPOCH should be set to a number of seconds since the epoch, in UTC. 4625 4626Building the Software: 4627====================== 4628 4629Building U-Boot has been tested in several native build environments 4630and in many different cross environments. Of course we cannot support 4631all possibly existing versions of cross development tools in all 4632(potentially obsolete) versions. In case of tool chain problems we 4633recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK) 4634which is extensively used to build and test U-Boot. 4635 4636If you are not using a native environment, it is assumed that you 4637have GNU cross compiling tools available in your path. In this case, 4638you must set the environment variable CROSS_COMPILE in your shell. 4639Note that no changes to the Makefile or any other source files are 4640necessary. For example using the ELDK on a 4xx CPU, please enter: 4641 4642 $ CROSS_COMPILE=ppc_4xx- 4643 $ export CROSS_COMPILE 4644 4645Note: If you wish to generate Windows versions of the utilities in 4646 the tools directory you can use the MinGW toolchain 4647 (http://www.mingw.org). Set your HOST tools to the MinGW 4648 toolchain and execute 'make tools'. For example: 4649 4650 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools 4651 4652 Binaries such as tools/mkimage.exe will be created which can 4653 be executed on computers running Windows. 4654 4655U-Boot is intended to be simple to build. After installing the 4656sources you must configure U-Boot for one specific board type. This 4657is done by typing: 4658 4659 make NAME_defconfig 4660 4661where "NAME_defconfig" is the name of one of the existing configu- 4662rations; see boards.cfg for supported names. 4663 4664Note: for some board special configuration names may exist; check if 4665 additional information is available from the board vendor; for 4666 instance, the TQM823L systems are available without (standard) 4667 or with LCD support. You can select such additional "features" 4668 when choosing the configuration, i. e. 4669 4670 make TQM823L_defconfig 4671 - will configure for a plain TQM823L, i. e. no LCD support 4672 4673 make TQM823L_LCD_defconfig 4674 - will configure for a TQM823L with U-Boot console on LCD 4675 4676 etc. 4677 4678 4679Finally, type "make all", and you should get some working U-Boot 4680images ready for download to / installation on your system: 4681 4682- "u-boot.bin" is a raw binary image 4683- "u-boot" is an image in ELF binary format 4684- "u-boot.srec" is in Motorola S-Record format 4685 4686By default the build is performed locally and the objects are saved 4687in the source directory. One of the two methods can be used to change 4688this behavior and build U-Boot to some external directory: 4689 46901. Add O= to the make command line invocations: 4691 4692 make O=/tmp/build distclean 4693 make O=/tmp/build NAME_defconfig 4694 make O=/tmp/build all 4695 46962. Set environment variable KBUILD_OUTPUT to point to the desired location: 4697 4698 export KBUILD_OUTPUT=/tmp/build 4699 make distclean 4700 make NAME_defconfig 4701 make all 4702 4703Note that the command line "O=" setting overrides the KBUILD_OUTPUT environment 4704variable. 4705 4706 4707Please be aware that the Makefiles assume you are using GNU make, so 4708for instance on NetBSD you might need to use "gmake" instead of 4709native "make". 4710 4711 4712If the system board that you have is not listed, then you will need 4713to port U-Boot to your hardware platform. To do this, follow these 4714steps: 4715 47161. Create a new directory to hold your board specific code. Add any 4717 files you need. In your board directory, you will need at least 4718 the "Makefile" and a "<board>.c". 47192. Create a new configuration file "include/configs/<board>.h" for 4720 your board. 47213. If you're porting U-Boot to a new CPU, then also create a new 4722 directory to hold your CPU specific code. Add any files you need. 47234. Run "make <board>_defconfig" with your new name. 47245. Type "make", and you should get a working "u-boot.srec" file 4725 to be installed on your target system. 47266. Debug and solve any problems that might arise. 4727 [Of course, this last step is much harder than it sounds.] 4728 4729 4730Testing of U-Boot Modifications, Ports to New Hardware, etc.: 4731============================================================== 4732 4733If you have modified U-Boot sources (for instance added a new board 4734or support for new devices, a new CPU, etc.) you are expected to 4735provide feedback to the other developers. The feedback normally takes 4736the form of a "patch", i. e. a context diff against a certain (latest 4737official or latest in the git repository) version of U-Boot sources. 4738 4739But before you submit such a patch, please verify that your modifi- 4740cation did not break existing code. At least make sure that *ALL* of 4741the supported boards compile WITHOUT ANY compiler warnings. To do so, 4742just run the buildman script (tools/buildman/buildman), which will 4743configure and build U-Boot for ALL supported system. Be warned, this 4744will take a while. Please see the buildman README, or run 'buildman -H' 4745for documentation. 4746 4747 4748See also "U-Boot Porting Guide" below. 4749 4750 4751Monitor Commands - Overview: 4752============================ 4753 4754go - start application at address 'addr' 4755run - run commands in an environment variable 4756bootm - boot application image from memory 4757bootp - boot image via network using BootP/TFTP protocol 4758bootz - boot zImage from memory 4759tftpboot- boot image via network using TFTP protocol 4760 and env variables "ipaddr" and "serverip" 4761 (and eventually "gatewayip") 4762tftpput - upload a file via network using TFTP protocol 4763rarpboot- boot image via network using RARP/TFTP protocol 4764diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 4765loads - load S-Record file over serial line 4766loadb - load binary file over serial line (kermit mode) 4767md - memory display 4768mm - memory modify (auto-incrementing) 4769nm - memory modify (constant address) 4770mw - memory write (fill) 4771cp - memory copy 4772cmp - memory compare 4773crc32 - checksum calculation 4774i2c - I2C sub-system 4775sspi - SPI utility commands 4776base - print or set address offset 4777printenv- print environment variables 4778setenv - set environment variables 4779saveenv - save environment variables to persistent storage 4780protect - enable or disable FLASH write protection 4781erase - erase FLASH memory 4782flinfo - print FLASH memory information 4783nand - NAND memory operations (see doc/README.nand) 4784bdinfo - print Board Info structure 4785iminfo - print header information for application image 4786coninfo - print console devices and informations 4787ide - IDE sub-system 4788loop - infinite loop on address range 4789loopw - infinite write loop on address range 4790mtest - simple RAM test 4791icache - enable or disable instruction cache 4792dcache - enable or disable data cache 4793reset - Perform RESET of the CPU 4794echo - echo args to console 4795version - print monitor version 4796help - print online help 4797? - alias for 'help' 4798 4799 4800Monitor Commands - Detailed Description: 4801======================================== 4802 4803TODO. 4804 4805For now: just type "help <command>". 4806 4807 4808Environment Variables: 4809====================== 4810 4811U-Boot supports user configuration using Environment Variables which 4812can be made persistent by saving to Flash memory. 4813 4814Environment Variables are set using "setenv", printed using 4815"printenv", and saved to Flash using "saveenv". Using "setenv" 4816without a value can be used to delete a variable from the 4817environment. As long as you don't save the environment you are 4818working with an in-memory copy. In case the Flash area containing the 4819environment is erased by accident, a default environment is provided. 4820 4821Some configuration options can be set using Environment Variables. 4822 4823List of environment variables (most likely not complete): 4824 4825 baudrate - see CONFIG_BAUDRATE 4826 4827 bootdelay - see CONFIG_BOOTDELAY 4828 4829 bootcmd - see CONFIG_BOOTCOMMAND 4830 4831 bootargs - Boot arguments when booting an RTOS image 4832 4833 bootfile - Name of the image to load with TFTP 4834 4835 bootm_low - Memory range available for image processing in the bootm 4836 command can be restricted. This variable is given as 4837 a hexadecimal number and defines lowest address allowed 4838 for use by the bootm command. See also "bootm_size" 4839 environment variable. Address defined by "bootm_low" is 4840 also the base of the initial memory mapping for the Linux 4841 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and 4842 bootm_mapsize. 4843 4844 bootm_mapsize - Size of the initial memory mapping for the Linux kernel. 4845 This variable is given as a hexadecimal number and it 4846 defines the size of the memory region starting at base 4847 address bootm_low that is accessible by the Linux kernel 4848 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used 4849 as the default value if it is defined, and bootm_size is 4850 used otherwise. 4851 4852 bootm_size - Memory range available for image processing in the bootm 4853 command can be restricted. This variable is given as 4854 a hexadecimal number and defines the size of the region 4855 allowed for use by the bootm command. See also "bootm_low" 4856 environment variable. 4857 4858 updatefile - Location of the software update file on a TFTP server, used 4859 by the automatic software update feature. Please refer to 4860 documentation in doc/README.update for more details. 4861 4862 autoload - if set to "no" (any string beginning with 'n'), 4863 "bootp" will just load perform a lookup of the 4864 configuration from the BOOTP server, but not try to 4865 load any image using TFTP 4866 4867 autostart - if set to "yes", an image loaded using the "bootp", 4868 "rarpboot", "tftpboot" or "diskboot" commands will 4869 be automatically started (by internally calling 4870 "bootm") 4871 4872 If set to "no", a standalone image passed to the 4873 "bootm" command will be copied to the load address 4874 (and eventually uncompressed), but NOT be started. 4875 This can be used to load and uncompress arbitrary 4876 data. 4877 4878 fdt_high - if set this restricts the maximum address that the 4879 flattened device tree will be copied into upon boot. 4880 For example, if you have a system with 1 GB memory 4881 at physical address 0x10000000, while Linux kernel 4882 only recognizes the first 704 MB as low memory, you 4883 may need to set fdt_high as 0x3C000000 to have the 4884 device tree blob be copied to the maximum address 4885 of the 704 MB low memory, so that Linux kernel can 4886 access it during the boot procedure. 4887 4888 If this is set to the special value 0xFFFFFFFF then 4889 the fdt will not be copied at all on boot. For this 4890 to work it must reside in writable memory, have 4891 sufficient padding on the end of it for u-boot to 4892 add the information it needs into it, and the memory 4893 must be accessible by the kernel. 4894 4895 fdtcontroladdr- if set this is the address of the control flattened 4896 device tree used by U-Boot when CONFIG_OF_CONTROL is 4897 defined. 4898 4899 i2cfast - (PPC405GP|PPC405EP only) 4900 if set to 'y' configures Linux I2C driver for fast 4901 mode (400kHZ). This environment variable is used in 4902 initialization code. So, for changes to be effective 4903 it must be saved and board must be reset. 4904 4905 initrd_high - restrict positioning of initrd images: 4906 If this variable is not set, initrd images will be 4907 copied to the highest possible address in RAM; this 4908 is usually what you want since it allows for 4909 maximum initrd size. If for some reason you want to 4910 make sure that the initrd image is loaded below the 4911 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment 4912 variable to a value of "no" or "off" or "0". 4913 Alternatively, you can set it to a maximum upper 4914 address to use (U-Boot will still check that it 4915 does not overwrite the U-Boot stack and data). 4916 4917 For instance, when you have a system with 16 MB 4918 RAM, and want to reserve 4 MB from use by Linux, 4919 you can do this by adding "mem=12M" to the value of 4920 the "bootargs" variable. However, now you must make 4921 sure that the initrd image is placed in the first 4922 12 MB as well - this can be done with 4923 4924 setenv initrd_high 00c00000 4925 4926 If you set initrd_high to 0xFFFFFFFF, this is an 4927 indication to U-Boot that all addresses are legal 4928 for the Linux kernel, including addresses in flash 4929 memory. In this case U-Boot will NOT COPY the 4930 ramdisk at all. This may be useful to reduce the 4931 boot time on your system, but requires that this 4932 feature is supported by your Linux kernel. 4933 4934 ipaddr - IP address; needed for tftpboot command 4935 4936 loadaddr - Default load address for commands like "bootp", 4937 "rarpboot", "tftpboot", "loadb" or "diskboot" 4938 4939 loads_echo - see CONFIG_LOADS_ECHO 4940 4941 serverip - TFTP server IP address; needed for tftpboot command 4942 4943 bootretry - see CONFIG_BOOT_RETRY_TIME 4944 4945 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 4946 4947 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 4948 4949 ethprime - controls which interface is used first. 4950 4951 ethact - controls which interface is currently active. 4952 For example you can do the following 4953 4954 => setenv ethact FEC 4955 => ping 192.168.0.1 # traffic sent on FEC 4956 => setenv ethact SCC 4957 => ping 10.0.0.1 # traffic sent on SCC 4958 4959 ethrotate - When set to "no" U-Boot does not go through all 4960 available network interfaces. 4961 It just stays at the currently selected interface. 4962 4963 netretry - When set to "no" each network operation will 4964 either succeed or fail without retrying. 4965 When set to "once" the network operation will 4966 fail when all the available network interfaces 4967 are tried once without success. 4968 Useful on scripts which control the retry operation 4969 themselves. 4970 4971 npe_ucode - set load address for the NPE microcode 4972 4973 silent_linux - If set then Linux will be told to boot silently, by 4974 changing the console to be empty. If "yes" it will be 4975 made silent. If "no" it will not be made silent. If 4976 unset, then it will be made silent if the U-Boot console 4977 is silent. 4978 4979 tftpsrcp - If this is set, the value is used for TFTP's 4980 UDP source port. 4981 4982 tftpdstp - If this is set, the value is used for TFTP's UDP 4983 destination port instead of the Well Know Port 69. 4984 4985 tftpblocksize - Block size to use for TFTP transfers; if not set, 4986 we use the TFTP server's default block size 4987 4988 tftptimeout - Retransmission timeout for TFTP packets (in milli- 4989 seconds, minimum value is 1000 = 1 second). Defines 4990 when a packet is considered to be lost so it has to 4991 be retransmitted. The default is 5000 = 5 seconds. 4992 Lowering this value may make downloads succeed 4993 faster in networks with high packet loss rates or 4994 with unreliable TFTP servers. 4995 4996 tftptimeoutcountmax - maximum count of TFTP timeouts (no 4997 unit, minimum value = 0). Defines how many timeouts 4998 can happen during a single file transfer before that 4999 transfer is aborted. The default is 10, and 0 means 5000 'no timeouts allowed'. Increasing this value may help 5001 downloads succeed with high packet loss rates, or with 5002 unreliable TFTP servers or client hardware. 5003 5004 vlan - When set to a value < 4095 the traffic over 5005 Ethernet is encapsulated/received over 802.1q 5006 VLAN tagged frames. 5007 5008 bootpretryperiod - Period during which BOOTP/DHCP sends retries. 5009 Unsigned value, in milliseconds. If not set, the period will 5010 be either the default (28000), or a value based on 5011 CONFIG_NET_RETRY_COUNT, if defined. This value has 5012 precedence over the valu based on CONFIG_NET_RETRY_COUNT. 5013 5014The following image location variables contain the location of images 5015used in booting. The "Image" column gives the role of the image and is 5016not an environment variable name. The other columns are environment 5017variable names. "File Name" gives the name of the file on a TFTP 5018server, "RAM Address" gives the location in RAM the image will be 5019loaded to, and "Flash Location" gives the image's address in NOR 5020flash or offset in NAND flash. 5021 5022*Note* - these variables don't have to be defined for all boards, some 5023boards currently use other variables for these purposes, and some 5024boards use these variables for other purposes. 5025 5026Image File Name RAM Address Flash Location 5027----- --------- ----------- -------------- 5028u-boot u-boot u-boot_addr_r u-boot_addr 5029Linux kernel bootfile kernel_addr_r kernel_addr 5030device tree blob fdtfile fdt_addr_r fdt_addr 5031ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr 5032 5033The following environment variables may be used and automatically 5034updated by the network boot commands ("bootp" and "rarpboot"), 5035depending the information provided by your boot server: 5036 5037 bootfile - see above 5038 dnsip - IP address of your Domain Name Server 5039 dnsip2 - IP address of your secondary Domain Name Server 5040 gatewayip - IP address of the Gateway (Router) to use 5041 hostname - Target hostname 5042 ipaddr - see above 5043 netmask - Subnet Mask 5044 rootpath - Pathname of the root filesystem on the NFS server 5045 serverip - see above 5046 5047 5048There are two special Environment Variables: 5049 5050 serial# - contains hardware identification information such 5051 as type string and/or serial number 5052 ethaddr - Ethernet address 5053 5054These variables can be set only once (usually during manufacturing of 5055the board). U-Boot refuses to delete or overwrite these variables 5056once they have been set once. 5057 5058 5059Further special Environment Variables: 5060 5061 ver - Contains the U-Boot version string as printed 5062 with the "version" command. This variable is 5063 readonly (see CONFIG_VERSION_VARIABLE). 5064 5065 5066Please note that changes to some configuration parameters may take 5067only effect after the next boot (yes, that's just like Windoze :-). 5068 5069 5070Callback functions for environment variables: 5071--------------------------------------------- 5072 5073For some environment variables, the behavior of u-boot needs to change 5074when their values are changed. This functionality allows functions to 5075be associated with arbitrary variables. On creation, overwrite, or 5076deletion, the callback will provide the opportunity for some side 5077effect to happen or for the change to be rejected. 5078 5079The callbacks are named and associated with a function using the 5080U_BOOT_ENV_CALLBACK macro in your board or driver code. 5081 5082These callbacks are associated with variables in one of two ways. The 5083static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC 5084in the board configuration to a string that defines a list of 5085associations. The list must be in the following format: 5086 5087 entry = variable_name[:callback_name] 5088 list = entry[,list] 5089 5090If the callback name is not specified, then the callback is deleted. 5091Spaces are also allowed anywhere in the list. 5092 5093Callbacks can also be associated by defining the ".callbacks" variable 5094with the same list format above. Any association in ".callbacks" will 5095override any association in the static list. You can define 5096CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the 5097".callbacks" environment variable in the default or embedded environment. 5098 5099If CONFIG_REGEX is defined, the variable_name above is evaluated as a 5100regular expression. This allows multiple variables to be connected to 5101the same callback without explicitly listing them all out. 5102 5103 5104Command Line Parsing: 5105===================== 5106 5107There are two different command line parsers available with U-Boot: 5108the old "simple" one, and the much more powerful "hush" shell: 5109 5110Old, simple command line parser: 5111-------------------------------- 5112 5113- supports environment variables (through setenv / saveenv commands) 5114- several commands on one line, separated by ';' 5115- variable substitution using "... ${name} ..." syntax 5116- special characters ('$', ';') can be escaped by prefixing with '\', 5117 for example: 5118 setenv bootcmd bootm \${address} 5119- You can also escape text by enclosing in single apostrophes, for example: 5120 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off' 5121 5122Hush shell: 5123----------- 5124 5125- similar to Bourne shell, with control structures like 5126 if...then...else...fi, for...do...done; while...do...done, 5127 until...do...done, ... 5128- supports environment ("global") variables (through setenv / saveenv 5129 commands) and local shell variables (through standard shell syntax 5130 "name=value"); only environment variables can be used with "run" 5131 command 5132 5133General rules: 5134-------------- 5135 5136(1) If a command line (or an environment variable executed by a "run" 5137 command) contains several commands separated by semicolon, and 5138 one of these commands fails, then the remaining commands will be 5139 executed anyway. 5140 5141(2) If you execute several variables with one call to run (i. e. 5142 calling run with a list of variables as arguments), any failing 5143 command will cause "run" to terminate, i. e. the remaining 5144 variables are not executed. 5145 5146Note for Redundant Ethernet Interfaces: 5147======================================= 5148 5149Some boards come with redundant Ethernet interfaces; U-Boot supports 5150such configurations and is capable of automatic selection of a 5151"working" interface when needed. MAC assignment works as follows: 5152 5153Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 5154MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 5155"eth1addr" (=>eth1), "eth2addr", ... 5156 5157If the network interface stores some valid MAC address (for instance 5158in SROM), this is used as default address if there is NO correspon- 5159ding setting in the environment; if the corresponding environment 5160variable is set, this overrides the settings in the card; that means: 5161 5162o If the SROM has a valid MAC address, and there is no address in the 5163 environment, the SROM's address is used. 5164 5165o If there is no valid address in the SROM, and a definition in the 5166 environment exists, then the value from the environment variable is 5167 used. 5168 5169o If both the SROM and the environment contain a MAC address, and 5170 both addresses are the same, this MAC address is used. 5171 5172o If both the SROM and the environment contain a MAC address, and the 5173 addresses differ, the value from the environment is used and a 5174 warning is printed. 5175 5176o If neither SROM nor the environment contain a MAC address, an error 5177 is raised. If CONFIG_NET_RANDOM_ETHADDR is defined, then in this case 5178 a random, locally-assigned MAC is used. 5179 5180If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses 5181will be programmed into hardware as part of the initialization process. This 5182may be skipped by setting the appropriate 'ethmacskip' environment variable. 5183The naming convention is as follows: 5184"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc. 5185 5186Image Formats: 5187============== 5188 5189U-Boot is capable of booting (and performing other auxiliary operations on) 5190images in two formats: 5191 5192New uImage format (FIT) 5193----------------------- 5194 5195Flexible and powerful format based on Flattened Image Tree -- FIT (similar 5196to Flattened Device Tree). It allows the use of images with multiple 5197components (several kernels, ramdisks, etc.), with contents protected by 5198SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory. 5199 5200 5201Old uImage format 5202----------------- 5203 5204Old image format is based on binary files which can be basically anything, 5205preceded by a special header; see the definitions in include/image.h for 5206details; basically, the header defines the following image properties: 5207 5208* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 5209 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 5210 LynxOS, pSOS, QNX, RTEMS, INTEGRITY; 5211 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS, 5212 INTEGRITY). 5213* Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86, 5214 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 5215 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC). 5216* Compression Type (uncompressed, gzip, bzip2) 5217* Load Address 5218* Entry Point 5219* Image Name 5220* Image Timestamp 5221 5222The header is marked by a special Magic Number, and both the header 5223and the data portions of the image are secured against corruption by 5224CRC32 checksums. 5225 5226 5227Linux Support: 5228============== 5229 5230Although U-Boot should support any OS or standalone application 5231easily, the main focus has always been on Linux during the design of 5232U-Boot. 5233 5234U-Boot includes many features that so far have been part of some 5235special "boot loader" code within the Linux kernel. Also, any 5236"initrd" images to be used are no longer part of one big Linux image; 5237instead, kernel and "initrd" are separate images. This implementation 5238serves several purposes: 5239 5240- the same features can be used for other OS or standalone 5241 applications (for instance: using compressed images to reduce the 5242 Flash memory footprint) 5243 5244- it becomes much easier to port new Linux kernel versions because 5245 lots of low-level, hardware dependent stuff are done by U-Boot 5246 5247- the same Linux kernel image can now be used with different "initrd" 5248 images; of course this also means that different kernel images can 5249 be run with the same "initrd". This makes testing easier (you don't 5250 have to build a new "zImage.initrd" Linux image when you just 5251 change a file in your "initrd"). Also, a field-upgrade of the 5252 software is easier now. 5253 5254 5255Linux HOWTO: 5256============ 5257 5258Porting Linux to U-Boot based systems: 5259--------------------------------------- 5260 5261U-Boot cannot save you from doing all the necessary modifications to 5262configure the Linux device drivers for use with your target hardware 5263(no, we don't intend to provide a full virtual machine interface to 5264Linux :-). 5265 5266But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot). 5267 5268Just make sure your machine specific header file (for instance 5269include/asm-ppc/tqm8xx.h) includes the same definition of the Board 5270Information structure as we define in include/asm-<arch>/u-boot.h, 5271and make sure that your definition of IMAP_ADDR uses the same value 5272as your U-Boot configuration in CONFIG_SYS_IMMR. 5273 5274Note that U-Boot now has a driver model, a unified model for drivers. 5275If you are adding a new driver, plumb it into driver model. If there 5276is no uclass available, you are encouraged to create one. See 5277doc/driver-model. 5278 5279 5280Configuring the Linux kernel: 5281----------------------------- 5282 5283No specific requirements for U-Boot. Make sure you have some root 5284device (initial ramdisk, NFS) for your target system. 5285 5286 5287Building a Linux Image: 5288----------------------- 5289 5290With U-Boot, "normal" build targets like "zImage" or "bzImage" are 5291not used. If you use recent kernel source, a new build target 5292"uImage" will exist which automatically builds an image usable by 5293U-Boot. Most older kernels also have support for a "pImage" target, 5294which was introduced for our predecessor project PPCBoot and uses a 5295100% compatible format. 5296 5297Example: 5298 5299 make TQM850L_defconfig 5300 make oldconfig 5301 make dep 5302 make uImage 5303 5304The "uImage" build target uses a special tool (in 'tools/mkimage') to 5305encapsulate a compressed Linux kernel image with header information, 5306CRC32 checksum etc. for use with U-Boot. This is what we are doing: 5307 5308* build a standard "vmlinux" kernel image (in ELF binary format): 5309 5310* convert the kernel into a raw binary image: 5311 5312 ${CROSS_COMPILE}-objcopy -O binary \ 5313 -R .note -R .comment \ 5314 -S vmlinux linux.bin 5315 5316* compress the binary image: 5317 5318 gzip -9 linux.bin 5319 5320* package compressed binary image for U-Boot: 5321 5322 mkimage -A ppc -O linux -T kernel -C gzip \ 5323 -a 0 -e 0 -n "Linux Kernel Image" \ 5324 -d linux.bin.gz uImage 5325 5326 5327The "mkimage" tool can also be used to create ramdisk images for use 5328with U-Boot, either separated from the Linux kernel image, or 5329combined into one file. "mkimage" encapsulates the images with a 64 5330byte header containing information about target architecture, 5331operating system, image type, compression method, entry points, time 5332stamp, CRC32 checksums, etc. 5333 5334"mkimage" can be called in two ways: to verify existing images and 5335print the header information, or to build new images. 5336 5337In the first form (with "-l" option) mkimage lists the information 5338contained in the header of an existing U-Boot image; this includes 5339checksum verification: 5340 5341 tools/mkimage -l image 5342 -l ==> list image header information 5343 5344The second form (with "-d" option) is used to build a U-Boot image 5345from a "data file" which is used as image payload: 5346 5347 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 5348 -n name -d data_file image 5349 -A ==> set architecture to 'arch' 5350 -O ==> set operating system to 'os' 5351 -T ==> set image type to 'type' 5352 -C ==> set compression type 'comp' 5353 -a ==> set load address to 'addr' (hex) 5354 -e ==> set entry point to 'ep' (hex) 5355 -n ==> set image name to 'name' 5356 -d ==> use image data from 'datafile' 5357 5358Right now, all Linux kernels for PowerPC systems use the same load 5359address (0x00000000), but the entry point address depends on the 5360kernel version: 5361 5362- 2.2.x kernels have the entry point at 0x0000000C, 5363- 2.3.x and later kernels have the entry point at 0x00000000. 5364 5365So a typical call to build a U-Boot image would read: 5366 5367 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 5368 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 5369 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \ 5370 > examples/uImage.TQM850L 5371 Image Name: 2.4.4 kernel for TQM850L 5372 Created: Wed Jul 19 02:34:59 2000 5373 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5374 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 5375 Load Address: 0x00000000 5376 Entry Point: 0x00000000 5377 5378To verify the contents of the image (or check for corruption): 5379 5380 -> tools/mkimage -l examples/uImage.TQM850L 5381 Image Name: 2.4.4 kernel for TQM850L 5382 Created: Wed Jul 19 02:34:59 2000 5383 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5384 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 5385 Load Address: 0x00000000 5386 Entry Point: 0x00000000 5387 5388NOTE: for embedded systems where boot time is critical you can trade 5389speed for memory and install an UNCOMPRESSED image instead: this 5390needs more space in Flash, but boots much faster since it does not 5391need to be uncompressed: 5392 5393 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz 5394 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 5395 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 5396 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \ 5397 > examples/uImage.TQM850L-uncompressed 5398 Image Name: 2.4.4 kernel for TQM850L 5399 Created: Wed Jul 19 02:34:59 2000 5400 Image Type: PowerPC Linux Kernel Image (uncompressed) 5401 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 5402 Load Address: 0x00000000 5403 Entry Point: 0x00000000 5404 5405 5406Similar you can build U-Boot images from a 'ramdisk.image.gz' file 5407when your kernel is intended to use an initial ramdisk: 5408 5409 -> tools/mkimage -n 'Simple Ramdisk Image' \ 5410 > -A ppc -O linux -T ramdisk -C gzip \ 5411 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 5412 Image Name: Simple Ramdisk Image 5413 Created: Wed Jan 12 14:01:50 2000 5414 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5415 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 5416 Load Address: 0x00000000 5417 Entry Point: 0x00000000 5418 5419The "dumpimage" is a tool to disassemble images built by mkimage. Its "-i" 5420option performs the converse operation of the mkimage's second form (the "-d" 5421option). Given an image built by mkimage, the dumpimage extracts a "data file" 5422from the image: 5423 5424 tools/dumpimage -i image -T type -p position data_file 5425 -i ==> extract from the 'image' a specific 'data_file' 5426 -T ==> set image type to 'type' 5427 -p ==> 'position' (starting at 0) of the 'data_file' inside the 'image' 5428 5429 5430Installing a Linux Image: 5431------------------------- 5432 5433To downloading a U-Boot image over the serial (console) interface, 5434you must convert the image to S-Record format: 5435 5436 objcopy -I binary -O srec examples/image examples/image.srec 5437 5438The 'objcopy' does not understand the information in the U-Boot 5439image header, so the resulting S-Record file will be relative to 5440address 0x00000000. To load it to a given address, you need to 5441specify the target address as 'offset' parameter with the 'loads' 5442command. 5443 5444Example: install the image to address 0x40100000 (which on the 5445TQM8xxL is in the first Flash bank): 5446 5447 => erase 40100000 401FFFFF 5448 5449 .......... done 5450 Erased 8 sectors 5451 5452 => loads 40100000 5453 ## Ready for S-Record download ... 5454 ~>examples/image.srec 5455 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 5456 ... 5457 15989 15990 15991 15992 5458 [file transfer complete] 5459 [connected] 5460 ## Start Addr = 0x00000000 5461 5462 5463You can check the success of the download using the 'iminfo' command; 5464this includes a checksum verification so you can be sure no data 5465corruption happened: 5466 5467 => imi 40100000 5468 5469 ## Checking Image at 40100000 ... 5470 Image Name: 2.2.13 for initrd on TQM850L 5471 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5472 Data Size: 335725 Bytes = 327 kB = 0 MB 5473 Load Address: 00000000 5474 Entry Point: 0000000c 5475 Verifying Checksum ... OK 5476 5477 5478Boot Linux: 5479----------- 5480 5481The "bootm" command is used to boot an application that is stored in 5482memory (RAM or Flash). In case of a Linux kernel image, the contents 5483of the "bootargs" environment variable is passed to the kernel as 5484parameters. You can check and modify this variable using the 5485"printenv" and "setenv" commands: 5486 5487 5488 => printenv bootargs 5489 bootargs=root=/dev/ram 5490 5491 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5492 5493 => printenv bootargs 5494 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5495 5496 => bootm 40020000 5497 ## Booting Linux kernel at 40020000 ... 5498 Image Name: 2.2.13 for NFS on TQM850L 5499 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5500 Data Size: 381681 Bytes = 372 kB = 0 MB 5501 Load Address: 00000000 5502 Entry Point: 0000000c 5503 Verifying Checksum ... OK 5504 Uncompressing Kernel Image ... OK 5505 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 5506 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5507 time_init: decrementer frequency = 187500000/60 5508 Calibrating delay loop... 49.77 BogoMIPS 5509 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 5510 ... 5511 5512If you want to boot a Linux kernel with initial RAM disk, you pass 5513the memory addresses of both the kernel and the initrd image (PPBCOOT 5514format!) to the "bootm" command: 5515 5516 => imi 40100000 40200000 5517 5518 ## Checking Image at 40100000 ... 5519 Image Name: 2.2.13 for initrd on TQM850L 5520 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5521 Data Size: 335725 Bytes = 327 kB = 0 MB 5522 Load Address: 00000000 5523 Entry Point: 0000000c 5524 Verifying Checksum ... OK 5525 5526 ## Checking Image at 40200000 ... 5527 Image Name: Simple Ramdisk Image 5528 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5529 Data Size: 566530 Bytes = 553 kB = 0 MB 5530 Load Address: 00000000 5531 Entry Point: 00000000 5532 Verifying Checksum ... OK 5533 5534 => bootm 40100000 40200000 5535 ## Booting Linux kernel at 40100000 ... 5536 Image Name: 2.2.13 for initrd on TQM850L 5537 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5538 Data Size: 335725 Bytes = 327 kB = 0 MB 5539 Load Address: 00000000 5540 Entry Point: 0000000c 5541 Verifying Checksum ... OK 5542 Uncompressing Kernel Image ... OK 5543 ## Loading RAMDisk Image at 40200000 ... 5544 Image Name: Simple Ramdisk Image 5545 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5546 Data Size: 566530 Bytes = 553 kB = 0 MB 5547 Load Address: 00000000 5548 Entry Point: 00000000 5549 Verifying Checksum ... OK 5550 Loading Ramdisk ... OK 5551 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 5552 Boot arguments: root=/dev/ram 5553 time_init: decrementer frequency = 187500000/60 5554 Calibrating delay loop... 49.77 BogoMIPS 5555 ... 5556 RAMDISK: Compressed image found at block 0 5557 VFS: Mounted root (ext2 filesystem). 5558 5559 bash# 5560 5561Boot Linux and pass a flat device tree: 5562----------- 5563 5564First, U-Boot must be compiled with the appropriate defines. See the section 5565titled "Linux Kernel Interface" above for a more in depth explanation. The 5566following is an example of how to start a kernel and pass an updated 5567flat device tree: 5568 5569=> print oftaddr 5570oftaddr=0x300000 5571=> print oft 5572oft=oftrees/mpc8540ads.dtb 5573=> tftp $oftaddr $oft 5574Speed: 1000, full duplex 5575Using TSEC0 device 5576TFTP from server 192.168.1.1; our IP address is 192.168.1.101 5577Filename 'oftrees/mpc8540ads.dtb'. 5578Load address: 0x300000 5579Loading: # 5580done 5581Bytes transferred = 4106 (100a hex) 5582=> tftp $loadaddr $bootfile 5583Speed: 1000, full duplex 5584Using TSEC0 device 5585TFTP from server 192.168.1.1; our IP address is 192.168.1.2 5586Filename 'uImage'. 5587Load address: 0x200000 5588Loading:############ 5589done 5590Bytes transferred = 1029407 (fb51f hex) 5591=> print loadaddr 5592loadaddr=200000 5593=> print oftaddr 5594oftaddr=0x300000 5595=> bootm $loadaddr - $oftaddr 5596## Booting image at 00200000 ... 5597 Image Name: Linux-2.6.17-dirty 5598 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5599 Data Size: 1029343 Bytes = 1005.2 kB 5600 Load Address: 00000000 5601 Entry Point: 00000000 5602 Verifying Checksum ... OK 5603 Uncompressing Kernel Image ... OK 5604Booting using flat device tree at 0x300000 5605Using MPC85xx ADS machine description 5606Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb 5607[snip] 5608 5609 5610More About U-Boot Image Types: 5611------------------------------ 5612 5613U-Boot supports the following image types: 5614 5615 "Standalone Programs" are directly runnable in the environment 5616 provided by U-Boot; it is expected that (if they behave 5617 well) you can continue to work in U-Boot after return from 5618 the Standalone Program. 5619 "OS Kernel Images" are usually images of some Embedded OS which 5620 will take over control completely. Usually these programs 5621 will install their own set of exception handlers, device 5622 drivers, set up the MMU, etc. - this means, that you cannot 5623 expect to re-enter U-Boot except by resetting the CPU. 5624 "RAMDisk Images" are more or less just data blocks, and their 5625 parameters (address, size) are passed to an OS kernel that is 5626 being started. 5627 "Multi-File Images" contain several images, typically an OS 5628 (Linux) kernel image and one or more data images like 5629 RAMDisks. This construct is useful for instance when you want 5630 to boot over the network using BOOTP etc., where the boot 5631 server provides just a single image file, but you want to get 5632 for instance an OS kernel and a RAMDisk image. 5633 5634 "Multi-File Images" start with a list of image sizes, each 5635 image size (in bytes) specified by an "uint32_t" in network 5636 byte order. This list is terminated by an "(uint32_t)0". 5637 Immediately after the terminating 0 follow the images, one by 5638 one, all aligned on "uint32_t" boundaries (size rounded up to 5639 a multiple of 4 bytes). 5640 5641 "Firmware Images" are binary images containing firmware (like 5642 U-Boot or FPGA images) which usually will be programmed to 5643 flash memory. 5644 5645 "Script files" are command sequences that will be executed by 5646 U-Boot's command interpreter; this feature is especially 5647 useful when you configure U-Boot to use a real shell (hush) 5648 as command interpreter. 5649 5650Booting the Linux zImage: 5651------------------------- 5652 5653On some platforms, it's possible to boot Linux zImage. This is done 5654using the "bootz" command. The syntax of "bootz" command is the same 5655as the syntax of "bootm" command. 5656 5657Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply 5658kernel with raw initrd images. The syntax is slightly different, the 5659address of the initrd must be augmented by it's size, in the following 5660format: "<initrd addres>:<initrd size>". 5661 5662 5663Standalone HOWTO: 5664================= 5665 5666One of the features of U-Boot is that you can dynamically load and 5667run "standalone" applications, which can use some resources of 5668U-Boot like console I/O functions or interrupt services. 5669 5670Two simple examples are included with the sources: 5671 5672"Hello World" Demo: 5673------------------- 5674 5675'examples/hello_world.c' contains a small "Hello World" Demo 5676application; it is automatically compiled when you build U-Boot. 5677It's configured to run at address 0x00040004, so you can play with it 5678like that: 5679 5680 => loads 5681 ## Ready for S-Record download ... 5682 ~>examples/hello_world.srec 5683 1 2 3 4 5 6 7 8 9 10 11 ... 5684 [file transfer complete] 5685 [connected] 5686 ## Start Addr = 0x00040004 5687 5688 => go 40004 Hello World! This is a test. 5689 ## Starting application at 0x00040004 ... 5690 Hello World 5691 argc = 7 5692 argv[0] = "40004" 5693 argv[1] = "Hello" 5694 argv[2] = "World!" 5695 argv[3] = "This" 5696 argv[4] = "is" 5697 argv[5] = "a" 5698 argv[6] = "test." 5699 argv[7] = "<NULL>" 5700 Hit any key to exit ... 5701 5702 ## Application terminated, rc = 0x0 5703 5704Another example, which demonstrates how to register a CPM interrupt 5705handler with the U-Boot code, can be found in 'examples/timer.c'. 5706Here, a CPM timer is set up to generate an interrupt every second. 5707The interrupt service routine is trivial, just printing a '.' 5708character, but this is just a demo program. The application can be 5709controlled by the following keys: 5710 5711 ? - print current values og the CPM Timer registers 5712 b - enable interrupts and start timer 5713 e - stop timer and disable interrupts 5714 q - quit application 5715 5716 => loads 5717 ## Ready for S-Record download ... 5718 ~>examples/timer.srec 5719 1 2 3 4 5 6 7 8 9 10 11 ... 5720 [file transfer complete] 5721 [connected] 5722 ## Start Addr = 0x00040004 5723 5724 => go 40004 5725 ## Starting application at 0x00040004 ... 5726 TIMERS=0xfff00980 5727 Using timer 1 5728 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 5729 5730Hit 'b': 5731 [q, b, e, ?] Set interval 1000000 us 5732 Enabling timer 5733Hit '?': 5734 [q, b, e, ?] ........ 5735 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 5736Hit '?': 5737 [q, b, e, ?] . 5738 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 5739Hit '?': 5740 [q, b, e, ?] . 5741 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 5742Hit '?': 5743 [q, b, e, ?] . 5744 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 5745Hit 'e': 5746 [q, b, e, ?] ...Stopping timer 5747Hit 'q': 5748 [q, b, e, ?] ## Application terminated, rc = 0x0 5749 5750 5751Minicom warning: 5752================ 5753 5754Over time, many people have reported problems when trying to use the 5755"minicom" terminal emulation program for serial download. I (wd) 5756consider minicom to be broken, and recommend not to use it. Under 5757Unix, I recommend to use C-Kermit for general purpose use (and 5758especially for kermit binary protocol download ("loadb" command), and 5759use "cu" for S-Record download ("loads" command). See 5760http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3. 5761for help with kermit. 5762 5763 5764Nevertheless, if you absolutely want to use it try adding this 5765configuration to your "File transfer protocols" section: 5766 5767 Name Program Name U/D FullScr IO-Red. Multi 5768 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N 5769 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N 5770 5771 5772NetBSD Notes: 5773============= 5774 5775Starting at version 0.9.2, U-Boot supports NetBSD both as host 5776(build U-Boot) and target system (boots NetBSD/mpc8xx). 5777 5778Building requires a cross environment; it is known to work on 5779NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 5780need gmake since the Makefiles are not compatible with BSD make). 5781Note that the cross-powerpc package does not install include files; 5782attempting to build U-Boot will fail because <machine/ansi.h> is 5783missing. This file has to be installed and patched manually: 5784 5785 # cd /usr/pkg/cross/powerpc-netbsd/include 5786 # mkdir powerpc 5787 # ln -s powerpc machine 5788 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 5789 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 5790 5791Native builds *don't* work due to incompatibilities between native 5792and U-Boot include files. 5793 5794Booting assumes that (the first part of) the image booted is a 5795stage-2 loader which in turn loads and then invokes the kernel 5796proper. Loader sources will eventually appear in the NetBSD source 5797tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 5798meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz 5799 5800 5801Implementation Internals: 5802========================= 5803 5804The following is not intended to be a complete description of every 5805implementation detail. However, it should help to understand the 5806inner workings of U-Boot and make it easier to port it to custom 5807hardware. 5808 5809 5810Initial Stack, Global Data: 5811--------------------------- 5812 5813The implementation of U-Boot is complicated by the fact that U-Boot 5814starts running out of ROM (flash memory), usually without access to 5815system RAM (because the memory controller is not initialized yet). 5816This means that we don't have writable Data or BSS segments, and BSS 5817is not initialized as zero. To be able to get a C environment working 5818at all, we have to allocate at least a minimal stack. Implementation 5819options for this are defined and restricted by the CPU used: Some CPU 5820models provide on-chip memory (like the IMMR area on MPC8xx and 5821MPC826x processors), on others (parts of) the data cache can be 5822locked as (mis-) used as memory, etc. 5823 5824 Chris Hallinan posted a good summary of these issues to the 5825 U-Boot mailing list: 5826 5827 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 5828 From: "Chris Hallinan" <clh@net1plus.com> 5829 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 5830 ... 5831 5832 Correct me if I'm wrong, folks, but the way I understand it 5833 is this: Using DCACHE as initial RAM for Stack, etc, does not 5834 require any physical RAM backing up the cache. The cleverness 5835 is that the cache is being used as a temporary supply of 5836 necessary storage before the SDRAM controller is setup. It's 5837 beyond the scope of this list to explain the details, but you 5838 can see how this works by studying the cache architecture and 5839 operation in the architecture and processor-specific manuals. 5840 5841 OCM is On Chip Memory, which I believe the 405GP has 4K. It 5842 is another option for the system designer to use as an 5843 initial stack/RAM area prior to SDRAM being available. Either 5844 option should work for you. Using CS 4 should be fine if your 5845 board designers haven't used it for something that would 5846 cause you grief during the initial boot! It is frequently not 5847 used. 5848 5849 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere 5850 with your processor/board/system design. The default value 5851 you will find in any recent u-boot distribution in 5852 walnut.h should work for you. I'd set it to a value larger 5853 than your SDRAM module. If you have a 64MB SDRAM module, set 5854 it above 400_0000. Just make sure your board has no resources 5855 that are supposed to respond to that address! That code in 5856 start.S has been around a while and should work as is when 5857 you get the config right. 5858 5859 -Chris Hallinan 5860 DS4.COM, Inc. 5861 5862It is essential to remember this, since it has some impact on the C 5863code for the initialization procedures: 5864 5865* Initialized global data (data segment) is read-only. Do not attempt 5866 to write it. 5867 5868* Do not use any uninitialized global data (or implicitly initialized 5869 as zero data - BSS segment) at all - this is undefined, initiali- 5870 zation is performed later (when relocating to RAM). 5871 5872* Stack space is very limited. Avoid big data buffers or things like 5873 that. 5874 5875Having only the stack as writable memory limits means we cannot use 5876normal global data to share information between the code. But it 5877turned out that the implementation of U-Boot can be greatly 5878simplified by making a global data structure (gd_t) available to all 5879functions. We could pass a pointer to this data as argument to _all_ 5880functions, but this would bloat the code. Instead we use a feature of 5881the GCC compiler (Global Register Variables) to share the data: we 5882place a pointer (gd) to the global data into a register which we 5883reserve for this purpose. 5884 5885When choosing a register for such a purpose we are restricted by the 5886relevant (E)ABI specifications for the current architecture, and by 5887GCC's implementation. 5888 5889For PowerPC, the following registers have specific use: 5890 R1: stack pointer 5891 R2: reserved for system use 5892 R3-R4: parameter passing and return values 5893 R5-R10: parameter passing 5894 R13: small data area pointer 5895 R30: GOT pointer 5896 R31: frame pointer 5897 5898 (U-Boot also uses R12 as internal GOT pointer. r12 5899 is a volatile register so r12 needs to be reset when 5900 going back and forth between asm and C) 5901 5902 ==> U-Boot will use R2 to hold a pointer to the global data 5903 5904 Note: on PPC, we could use a static initializer (since the 5905 address of the global data structure is known at compile time), 5906 but it turned out that reserving a register results in somewhat 5907 smaller code - although the code savings are not that big (on 5908 average for all boards 752 bytes for the whole U-Boot image, 5909 624 text + 127 data). 5910 5911On ARM, the following registers are used: 5912 5913 R0: function argument word/integer result 5914 R1-R3: function argument word 5915 R9: platform specific 5916 R10: stack limit (used only if stack checking is enabled) 5917 R11: argument (frame) pointer 5918 R12: temporary workspace 5919 R13: stack pointer 5920 R14: link register 5921 R15: program counter 5922 5923 ==> U-Boot will use R9 to hold a pointer to the global data 5924 5925 Note: on ARM, only R_ARM_RELATIVE relocations are supported. 5926 5927On Nios II, the ABI is documented here: 5928 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf 5929 5930 ==> U-Boot will use gp to hold a pointer to the global data 5931 5932 Note: on Nios II, we give "-G0" option to gcc and don't use gp 5933 to access small data sections, so gp is free. 5934 5935On NDS32, the following registers are used: 5936 5937 R0-R1: argument/return 5938 R2-R5: argument 5939 R15: temporary register for assembler 5940 R16: trampoline register 5941 R28: frame pointer (FP) 5942 R29: global pointer (GP) 5943 R30: link register (LP) 5944 R31: stack pointer (SP) 5945 PC: program counter (PC) 5946 5947 ==> U-Boot will use R10 to hold a pointer to the global data 5948 5949NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope, 5950or current versions of GCC may "optimize" the code too much. 5951 5952Memory Management: 5953------------------ 5954 5955U-Boot runs in system state and uses physical addresses, i.e. the 5956MMU is not used either for address mapping nor for memory protection. 5957 5958The available memory is mapped to fixed addresses using the memory 5959controller. In this process, a contiguous block is formed for each 5960memory type (Flash, SDRAM, SRAM), even when it consists of several 5961physical memory banks. 5962 5963U-Boot is installed in the first 128 kB of the first Flash bank (on 5964TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 5965booting and sizing and initializing DRAM, the code relocates itself 5966to the upper end of DRAM. Immediately below the U-Boot code some 5967memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN 5968configuration setting]. Below that, a structure with global Board 5969Info data is placed, followed by the stack (growing downward). 5970 5971Additionally, some exception handler code is copied to the low 8 kB 5972of DRAM (0x00000000 ... 0x00001FFF). 5973 5974So a typical memory configuration with 16 MB of DRAM could look like 5975this: 5976 5977 0x0000 0000 Exception Vector code 5978 : 5979 0x0000 1FFF 5980 0x0000 2000 Free for Application Use 5981 : 5982 : 5983 5984 : 5985 : 5986 0x00FB FF20 Monitor Stack (Growing downward) 5987 0x00FB FFAC Board Info Data and permanent copy of global data 5988 0x00FC 0000 Malloc Arena 5989 : 5990 0x00FD FFFF 5991 0x00FE 0000 RAM Copy of Monitor Code 5992 ... eventually: LCD or video framebuffer 5993 ... eventually: pRAM (Protected RAM - unchanged by reset) 5994 0x00FF FFFF [End of RAM] 5995 5996 5997System Initialization: 5998---------------------- 5999 6000In the reset configuration, U-Boot starts at the reset entry point 6001(on most PowerPC systems at address 0x00000100). Because of the reset 6002configuration for CS0# this is a mirror of the on board Flash memory. 6003To be able to re-map memory U-Boot then jumps to its link address. 6004To be able to implement the initialization code in C, a (small!) 6005initial stack is set up in the internal Dual Ported RAM (in case CPUs 6006which provide such a feature like MPC8xx or MPC8260), or in a locked 6007part of the data cache. After that, U-Boot initializes the CPU core, 6008the caches and the SIU. 6009 6010Next, all (potentially) available memory banks are mapped using a 6011preliminary mapping. For example, we put them on 512 MB boundaries 6012(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 6013on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 6014programmed for SDRAM access. Using the temporary configuration, a 6015simple memory test is run that determines the size of the SDRAM 6016banks. 6017 6018When there is more than one SDRAM bank, and the banks are of 6019different size, the largest is mapped first. For equal size, the first 6020bank (CS2#) is mapped first. The first mapping is always for address 60210x00000000, with any additional banks following immediately to create 6022contiguous memory starting from 0. 6023 6024Then, the monitor installs itself at the upper end of the SDRAM area 6025and allocates memory for use by malloc() and for the global Board 6026Info data; also, the exception vector code is copied to the low RAM 6027pages, and the final stack is set up. 6028 6029Only after this relocation will you have a "normal" C environment; 6030until that you are restricted in several ways, mostly because you are 6031running from ROM, and because the code will have to be relocated to a 6032new address in RAM. 6033 6034 6035U-Boot Porting Guide: 6036---------------------- 6037 6038[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 6039list, October 2002] 6040 6041 6042int main(int argc, char *argv[]) 6043{ 6044 sighandler_t no_more_time; 6045 6046 signal(SIGALRM, no_more_time); 6047 alarm(PROJECT_DEADLINE - toSec (3 * WEEK)); 6048 6049 if (available_money > available_manpower) { 6050 Pay consultant to port U-Boot; 6051 return 0; 6052 } 6053 6054 Download latest U-Boot source; 6055 6056 Subscribe to u-boot mailing list; 6057 6058 if (clueless) 6059 email("Hi, I am new to U-Boot, how do I get started?"); 6060 6061 while (learning) { 6062 Read the README file in the top level directory; 6063 Read http://www.denx.de/twiki/bin/view/DULG/Manual; 6064 Read applicable doc/*.README; 6065 Read the source, Luke; 6066 /* find . -name "*.[chS]" | xargs grep -i <keyword> */ 6067 } 6068 6069 if (available_money > toLocalCurrency ($2500)) 6070 Buy a BDI3000; 6071 else 6072 Add a lot of aggravation and time; 6073 6074 if (a similar board exists) { /* hopefully... */ 6075 cp -a board/<similar> board/<myboard> 6076 cp include/configs/<similar>.h include/configs/<myboard>.h 6077 } else { 6078 Create your own board support subdirectory; 6079 Create your own board include/configs/<myboard>.h file; 6080 } 6081 Edit new board/<myboard> files 6082 Edit new include/configs/<myboard>.h 6083 6084 while (!accepted) { 6085 while (!running) { 6086 do { 6087 Add / modify source code; 6088 } until (compiles); 6089 Debug; 6090 if (clueless) 6091 email("Hi, I am having problems..."); 6092 } 6093 Send patch file to the U-Boot email list; 6094 if (reasonable critiques) 6095 Incorporate improvements from email list code review; 6096 else 6097 Defend code as written; 6098 } 6099 6100 return 0; 6101} 6102 6103void no_more_time (int sig) 6104{ 6105 hire_a_guru(); 6106} 6107 6108 6109Coding Standards: 6110----------------- 6111 6112All contributions to U-Boot should conform to the Linux kernel 6113coding style; see the file "Documentation/CodingStyle" and the script 6114"scripts/Lindent" in your Linux kernel source directory. 6115 6116Source files originating from a different project (for example the 6117MTD subsystem) are generally exempt from these guidelines and are not 6118reformatted to ease subsequent migration to newer versions of those 6119sources. 6120 6121Please note that U-Boot is implemented in C (and to some small parts in 6122Assembler); no C++ is used, so please do not use C++ style comments (//) 6123in your code. 6124 6125Please also stick to the following formatting rules: 6126- remove any trailing white space 6127- use TAB characters for indentation and vertical alignment, not spaces 6128- make sure NOT to use DOS '\r\n' line feeds 6129- do not add more than 2 consecutive empty lines to source files 6130- do not add trailing empty lines to source files 6131 6132Submissions which do not conform to the standards may be returned 6133with a request to reformat the changes. 6134 6135 6136Submitting Patches: 6137------------------- 6138 6139Since the number of patches for U-Boot is growing, we need to 6140establish some rules. Submissions which do not conform to these rules 6141may be rejected, even when they contain important and valuable stuff. 6142 6143Please see http://www.denx.de/wiki/U-Boot/Patches for details. 6144 6145Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>; 6146see http://lists.denx.de/mailman/listinfo/u-boot 6147 6148When you send a patch, please include the following information with 6149it: 6150 6151* For bug fixes: a description of the bug and how your patch fixes 6152 this bug. Please try to include a way of demonstrating that the 6153 patch actually fixes something. 6154 6155* For new features: a description of the feature and your 6156 implementation. 6157 6158* A CHANGELOG entry as plaintext (separate from the patch) 6159 6160* For major contributions, add a MAINTAINERS file with your 6161 information and associated file and directory references. 6162 6163* When you add support for a new board, don't forget to add a 6164 maintainer e-mail address to the boards.cfg file, too. 6165 6166* If your patch adds new configuration options, don't forget to 6167 document these in the README file. 6168 6169* The patch itself. If you are using git (which is *strongly* 6170 recommended) you can easily generate the patch using the 6171 "git format-patch". If you then use "git send-email" to send it to 6172 the U-Boot mailing list, you will avoid most of the common problems 6173 with some other mail clients. 6174 6175 If you cannot use git, use "diff -purN OLD NEW". If your version of 6176 diff does not support these options, then get the latest version of 6177 GNU diff. 6178 6179 The current directory when running this command shall be the parent 6180 directory of the U-Boot source tree (i. e. please make sure that 6181 your patch includes sufficient directory information for the 6182 affected files). 6183 6184 We prefer patches as plain text. MIME attachments are discouraged, 6185 and compressed attachments must not be used. 6186 6187* If one logical set of modifications affects or creates several 6188 files, all these changes shall be submitted in a SINGLE patch file. 6189 6190* Changesets that contain different, unrelated modifications shall be 6191 submitted as SEPARATE patches, one patch per changeset. 6192 6193 6194Notes: 6195 6196* Before sending the patch, run the buildman script on your patched 6197 source tree and make sure that no errors or warnings are reported 6198 for any of the boards. 6199 6200* Keep your modifications to the necessary minimum: A patch 6201 containing several unrelated changes or arbitrary reformats will be 6202 returned with a request to re-formatting / split it. 6203 6204* If you modify existing code, make sure that your new code does not 6205 add to the memory footprint of the code ;-) Small is beautiful! 6206 When adding new features, these should compile conditionally only 6207 (using #ifdef), and the resulting code with the new feature 6208 disabled must not need more memory than the old code without your 6209 modification. 6210 6211* Remember that there is a size limit of 100 kB per message on the 6212 u-boot mailing list. Bigger patches will be moderated. If they are 6213 reasonable and not too big, they will be acknowledged. But patches 6214 bigger than the size limit should be avoided. 6215