Makefile have been tested to some extent and can be considered
"working". In fact, many of them are used in production systems.
-In case of problems see the CHANGELOG and CREDITS files to find out
-who contributed the specific port. The boards.cfg file lists board
-maintainers.
+In case of problems see the CHANGELOG file to find out who contributed
+the specific port. In addition, there are various MAINTAINERS files
+scattered throughout the U-Boot source identifying the people or
+companies responsible for various boards and subsystems.
-Note: There is no CHANGELOG file in the actual U-Boot source tree;
-it can be created dynamically from the Git log using:
+Note: As of August, 2010, there is no longer a CHANGELOG file in the
+actual U-Boot source tree; however, it can be created dynamically
+from the Git log using:
make CHANGELOG
==================
In case you have questions about, problems with or contributions for
-U-Boot you should send a message to the U-Boot mailing list at
+U-Boot, you should send a message to the U-Boot mailing list at
<u-boot@lists.denx.de>. There is also an archive of previous traffic
on the mailing list - please search the archive before asking FAQ's.
Please see http://lists.denx.de/pipermail/u-boot and
Where to get source code:
=========================
-The U-Boot source code is maintained in the git repository at
+The U-Boot source code is maintained in the Git repository at
git://www.denx.de/git/u-boot.git ; you can browse it online at
http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary
/arch Architecture specific files
/arc Files generic to ARC architecture
- /cpu CPU specific files
- /arc700 Files specific to ARC 700 CPUs
- /lib Architecture specific library files
/arm Files generic to ARM architecture
- /cpu CPU specific files
- /arm720t Files specific to ARM 720 CPUs
- /arm920t Files specific to ARM 920 CPUs
- /at91 Files specific to Atmel AT91RM9200 CPU
- /imx Files specific to Freescale MC9328 i.MX CPUs
- /s3c24x0 Files specific to Samsung S3C24X0 CPUs
- /arm926ejs Files specific to ARM 926 CPUs
- /arm1136 Files specific to ARM 1136 CPUs
- /pxa Files specific to Intel XScale PXA CPUs
- /sa1100 Files specific to Intel StrongARM SA1100 CPUs
- /lib Architecture specific library files
/avr32 Files generic to AVR32 architecture
- /cpu CPU specific files
- /lib Architecture specific library files
/blackfin Files generic to Analog Devices Blackfin architecture
- /cpu CPU specific files
- /lib Architecture specific library files
/m68k Files generic to m68k architecture
- /cpu CPU specific files
- /mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs
- /mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs
- /mcf532x Files specific to Freescale ColdFire MCF5329 CPUs
- /mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs
- /mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs
- /lib Architecture specific library files
/microblaze Files generic to microblaze architecture
- /cpu CPU specific files
- /lib Architecture specific library files
/mips Files generic to MIPS architecture
- /cpu CPU specific files
- /mips32 Files specific to MIPS32 CPUs
- /mips64 Files specific to MIPS64 CPUs
- /lib Architecture specific library files
/nds32 Files generic to NDS32 architecture
- /cpu CPU specific files
- /n1213 Files specific to Andes Technology N1213 CPUs
- /lib Architecture specific library files
/nios2 Files generic to Altera NIOS2 architecture
- /cpu CPU specific files
- /lib Architecture specific library files
/openrisc Files generic to OpenRISC architecture
- /cpu CPU specific files
- /lib Architecture specific library files
/powerpc Files generic to PowerPC architecture
- /cpu CPU specific files
- /74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs
- /mpc5xx Files specific to Freescale MPC5xx CPUs
- /mpc5xxx Files specific to Freescale MPC5xxx CPUs
- /mpc8xx Files specific to Freescale MPC8xx CPUs
- /mpc824x Files specific to Freescale MPC824x CPUs
- /mpc8260 Files specific to Freescale MPC8260 CPUs
- /mpc85xx Files specific to Freescale MPC85xx CPUs
- /ppc4xx Files specific to AMCC PowerPC 4xx CPUs
- /lib Architecture specific library files
+ /sandbox Files generic to HW-independent "sandbox"
/sh Files generic to SH architecture
- /cpu CPU specific files
- /sh2 Files specific to sh2 CPUs
- /sh3 Files specific to sh3 CPUs
- /sh4 Files specific to sh4 CPUs
- /lib Architecture specific library files
/sparc Files generic to SPARC architecture
- /cpu CPU specific files
- /leon2 Files specific to Gaisler LEON2 SPARC CPU
- /leon3 Files specific to Gaisler LEON3 SPARC CPU
- /lib Architecture specific library files
/x86 Files generic to x86 architecture
- /cpu CPU specific files
- /lib Architecture specific library files
/api Machine/arch independent API for external apps
/board Board dependent files
/common Misc architecture independent functions
+/configs Board default configuration files
/disk Code for disk drive partition handling
/doc Documentation (don't expect too much)
/drivers Commonly used device drivers
/examples Example code for standalone applications, etc.
/fs Filesystem code (cramfs, ext2, jffs2, etc.)
/include Header Files
-/lib Files generic to all architectures
- /libfdt Library files to support flattened device trees
- /lzma Library files to support LZMA decompression
- /lzo Library files to support LZO decompression
+/lib Library routines generic to all architectures
+/Licenses Various license files
/net Networking code
/post Power On Self Test
-/spl Secondary Program Loader framework
+/scripts Various build scripts and Makefiles
+/test Various unit test files
/tools Tools to build S-Record or U-Boot images, etc.
Software Configuration:
you don't know what you're doing; they have names beginning with
"CONFIG_SYS_".
-Later we will add a configuration tool - probably similar to or even
-identical to what's used for the Linux kernel. Right now, we have to
-do the configuration by hand, which means creating some symbolic
-links and editing some configuration files. We use the TQM8xxL boards
-as an example here.
+Previously, all configuration was done by hand, which involved creating
+symbolic links and editing configuration files manually. More recently,
+U-Boot has added the Kbuild infrastructure used by the Linux kernel,
+allowing you to use the "make menuconfig" command to configure your
+build.
Selection of Processor Architecture and Board Type:
cd u-boot
make TQM823L_defconfig
-For the Cogent platform, you need to specify the CPU type as well;
-e.g. "make cogent_mpc8xx_defconfig". And also configure the cogent
-directory according to the instructions in cogent/README.
-
+Note: If you're looking for the default configuration file for a board
+you're sure used to be there but is now missing, check the file
+doc/README.scrapyard for a list of no longer supported boards.
Sandbox Environment:
--------------------
See board/sandbox/README.sandbox for more details.
+Board Initialisation Flow:
+--------------------------
+
+This is the intended start-up flow for boards. This should apply for both
+SPL and U-Boot proper (i.e. they both follow the same rules).
+
+Note: "SPL" stands for "Secondary Program Loader," which is explained in
+more detail later in this file.
+
+At present, SPL mostly uses a separate code path, but the function names
+and roles of each function are the same. Some boards or architectures
+may not conform to this. At least most ARM boards which use
+CONFIG_SPL_FRAMEWORK conform to this.
+
+Execution typically starts with an architecture-specific (and possibly
+CPU-specific) start.S file, such as:
+
+ - arch/arm/cpu/armv7/start.S
+ - arch/powerpc/cpu/mpc83xx/start.S
+ - arch/mips/cpu/start.S
+
+and so on. From there, three functions are called; the purpose and
+limitations of each of these functions are described below.
+
+lowlevel_init():
+ - purpose: essential init to permit execution to reach board_init_f()
+ - no global_data or BSS
+ - there is no stack (ARMv7 may have one but it will soon be removed)
+ - must not set up SDRAM or use console
+ - must only do the bare minimum to allow execution to continue to
+ board_init_f()
+ - this is almost never needed
+ - return normally from this function
+
+board_init_f():
+ - purpose: set up the machine ready for running board_init_r():
+ i.e. SDRAM and serial UART
+ - global_data is available
+ - stack is in SRAM
+ - BSS is not available, so you cannot use global/static variables,
+ only stack variables and global_data
+
+ Non-SPL-specific notes:
+ - dram_init() is called to set up DRAM. If already done in SPL this
+ can do nothing
+
+ SPL-specific notes:
+ - you can override the entire board_init_f() function with your own
+ version as needed.
+ - preloader_console_init() can be called here in extremis
+ - should set up SDRAM, and anything needed to make the UART work
+ - these is no need to clear BSS, it will be done by crt0.S
+ - must return normally from this function (don't call board_init_r()
+ directly)
+
+Here the BSS is cleared. For SPL, if CONFIG_SPL_STACK_R is defined, then at
+this point the stack and global_data are relocated to below
+CONFIG_SPL_STACK_R_ADDR. For non-SPL, U-Boot is relocated to run at the top of
+memory.
+
+board_init_r():
+ - purpose: main execution, common code
+ - global_data is available
+ - SDRAM is available
+ - BSS is available, all static/global variables can be used
+ - execution eventually continues to main_loop()
+
+ Non-SPL-specific notes:
+ - U-Boot is relocated to the top of memory and is now running from
+ there.
+
+ SPL-specific notes:
+ - stack is optionally in SDRAM, if CONFIG_SPL_STACK_R is defined and
+ CONFIG_SPL_STACK_R_ADDR points into SDRAM
+ - preloader_console_init() can be called here - typically this is
+ done by defining CONFIG_SPL_BOARD_INIT and then supplying a
+ spl_board_init() function containing this call
+ - loads U-Boot or (in falcon mode) Linux
+
+
+
Configuration Options:
----------------------
multiple fs option at one time
for marvell soc family
-- MPC824X Family Member (if CONFIG_MPC824X is defined)
- Define exactly one of
- CONFIG_MPC8240, CONFIG_MPC8245
-
- 8xx CPU Options: (if using an MPC8xx CPU)
CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if
get_gclk_freq() cannot work
CONFIG_A003399_NOR_WORKAROUND
Enables a workaround for IFC erratum A003399. It is only
- requred during NOR boot.
+ required during NOR boot.
CONFIG_A008044_WORKAROUND
Enables a workaround for T1040/T1042 erratum A008044. It is only
- requred during NAND boot and valid for Rev 1.0 SoC revision
+ required during NAND boot and valid for Rev 1.0 SoC revision
CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY
time of U-boot entry and is required to be re-initialized.
CONFIG_DEEP_SLEEP
- Inidcates this SoC supports deep sleep feature. If deep sleep is
+ Indicates this SoC supports deep sleep feature. If deep sleep is
supported, core will start to execute uboot when wakes up.
- Generic CPU options:
CONFIG_SYS_FSL_OTHER_DDR_NUM_CTRLS
Number of controllers used for other than main memory.
+ CONFIG_SYS_FSL_HAS_DP_DDR
+ Defines the SoC has DP-DDR used for DPAA.
+
CONFIG_SYS_FSL_SEC_BE
Defines the SEC controller register space as Big Endian
CONFIG_ARM_ERRATA_742230
CONFIG_ARM_ERRATA_743622
CONFIG_ARM_ERRATA_751472
- CONFIG_ARM_ERRATA_794072
CONFIG_ARM_ERRATA_761320
+ CONFIG_ARM_ERRATA_773022
+ CONFIG_ARM_ERRATA_774769
+ CONFIG_ARM_ERRATA_794072
If set, the workarounds for these ARM errata are applied early
during U-Boot startup. Note that these options force the
exists, unlike the similar options in the Linux kernel. Do not
set these options unless they apply!
-- Driver Model
- Driver model is a new framework for devices in U-Boot
- introduced in early 2014. U-Boot is being progressively
- moved over to this. It offers a consistent device structure,
- supports grouping devices into classes and has built-in
- handling of platform data and device tree.
-
- To enable transition to driver model in a relatively
- painful fashion, each subsystem can be independently
- switched between the legacy/ad-hoc approach and the new
- driver model using the options below. Also, many uclass
- interfaces include compatibility features which may be
- removed once the conversion of that subsystem is complete.
- As a result, the API provided by the subsystem may in fact
- not change with driver model.
-
- See doc/driver-model/README.txt for more information.
-
- CONFIG_DM
-
- Enable driver model. This brings in the core support,
- including scanning of platform data on start-up. If
- CONFIG_OF_CONTROL is enabled, the device tree will be
- scanned also when available.
-
- CONFIG_CMD_DM
-
- Enable driver model test commands. These allow you to print
- out the driver model tree and the uclasses.
-
- CONFIG_DM_DEMO
-
- Enable some demo devices and the 'demo' command. These are
- really only useful for playing around while trying to
- understand driver model in sandbox.
-
- CONFIG_SPL_DM
-
- Enable driver model in SPL. You will need to provide a
- suitable malloc() implementation. If you are not using the
- full malloc() enabled by CONFIG_SYS_SPL_MALLOC_START,
- consider using CONFIG_SYS_MALLOC_SIMPLE. In that case you
- must provide CONFIG_SYS_MALLOC_F_LEN to set the size.
- In most cases driver model will only allocate a few uclasses
- and devices in SPL, so 1KB should be enable. See
- CONFIG_SYS_MALLOC_F_LEN for more details on how to enable
- it.
-
- CONFIG_DM_SERIAL
-
- Enable driver model for serial. This replaces
- drivers/serial/serial.c with the serial uclass, which
- implements serial_putc() etc. The uclass interface is
- defined in include/serial.h.
-
- CONFIG_DM_GPIO
-
- Enable driver model for GPIO access. The standard GPIO
- interface (gpio_get_value(), etc.) is then implemented by
- the GPIO uclass. Drivers provide methods to query the
- particular GPIOs that they provide. The uclass interface
- is defined in include/asm-generic/gpio.h.
-
- CONFIG_DM_SPI
-
- Enable driver model for SPI. The SPI slave interface
- (spi_setup_slave(), spi_xfer(), etc.) is then implemented by
- the SPI uclass. Drivers provide methods to access the SPI
- buses that they control. The uclass interface is defined in
- include/spi.h. The existing spi_slave structure is attached
- as 'parent data' to every slave on each bus. Slaves
- typically use driver-private data instead of extending the
- spi_slave structure.
+ COUNTER_FREQUENCY
+ Generic timer clock source frequency.
- CONFIG_DM_SPI_FLASH
+ COUNTER_FREQUENCY_REAL
+ Generic timer clock source frequency if the real clock is
+ different from COUNTER_FREQUENCY, and can only be determined
+ at run time.
- Enable driver model for SPI flash. This SPI flash interface
- (spi_flash_probe(), spi_flash_write(), etc.) is then
- implemented by the SPI flash uclass. There is one standard
- SPI flash driver which knows how to probe most chips
- supported by U-Boot. The uclass interface is defined in
- include/spi_flash.h, but is currently fully compatible
- with the old interface to avoid confusion and duplication
- during the transition parent. SPI and SPI flash must be
- enabled together (it is not possible to use driver model
- for one and not the other).
+ NOTE: The following can be machine specific errata. These
+ do have ability to provide rudimentary version and machine
+ specific checks, but expect no product checks.
+ CONFIG_ARM_ERRATA_430973
+ CONFIG_ARM_ERRATA_454179
+ CONFIG_ARM_ERRATA_621766
+ CONFIG_ARM_ERRATA_798870
+ CONFIG_ARM_ERRATA_801819
- CONFIG_DM_CROS_EC
-
- Enable driver model for the Chrome OS EC interface. This
- allows the cros_ec SPI driver to operate with CONFIG_DM_SPI
- but otherwise makes few changes. Since cros_ec also supports
- I2C and LPC (which don't support driver model yet), a full
- conversion is not yet possible.
-
-
- ** Code size options: The following options are enabled by
- default except in SPL. Enable them explicitly to get these
- features in SPL.
-
- CONFIG_DM_WARN
-
- Enable the dm_warn() function. This can use up quite a bit
- of space for its strings.
-
- CONFIG_DM_STDIO
-
- Enable registering a serial device with the stdio library.
-
- CONFIG_DM_DEVICE_REMOVE
-
- Enable removing of devices.
+- Tegra SoC options:
+ CONFIG_TEGRA_SUPPORT_NON_SECURE
+ Support executing U-Boot in non-secure (NS) mode. Certain
+ impossible actions will be skipped if the CPU is in NS mode,
+ such as ARM architectural timer initialization.
- Linux Kernel Interface:
CONFIG_CLOCKS_IN_MHZ
CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
- When transferring memsize parameter to linux, some versions
+ When transferring memsize parameter to Linux, some versions
expect it to be in bytes, others in MB.
Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
- vxWorks boot parameters:
bootvx constructs a valid bootline using the following
- environments variables: bootfile, ipaddr, serverip, hostname.
+ environments variables: bootdev, bootfile, ipaddr, netmask,
+ serverip, gatewayip, hostname, othbootargs.
It loads the vxWorks image pointed bootfile.
- CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name
- CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address
- CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server
- CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters
-
- CONFIG_SYS_VXWORKS_ADD_PARAMS
-
- Add it at the end of the bootline. E.g "u=username pw=secret"
-
Note: If a "bootargs" environment is defined, it will overwride
the defaults discussed just above.
define this to a list of base addresses for each (supported)
port. See e.g. include/configs/versatile.h
- CONFIG_PL011_SERIAL_RLCR
-
- Some vendor versions of PL011 serial ports (e.g. ST-Ericsson U8500)
- have separate receive and transmit line control registers. Set
- this variable to initialize the extra register.
-
- CONFIG_PL011_SERIAL_FLUSH_ON_INIT
-
- On some platforms (e.g. U8500) U-Boot is loaded by a second stage
- boot loader that has already initialized the UART. Define this
- variable to flush the UART at init time.
-
CONFIG_SERIAL_HW_FLOW_CONTROL
Define this variable to enable hw flow control in serial driver.
(0-5, cf. cfb_console.c)
VIDEO_FB_ADRS framebuffer address
VIDEO_KBD_INIT_FCT keyboard int fct
- (i.e. i8042_kbd_init())
+ (i.e. rx51_kp_init())
VIDEO_TSTC_FCT test char fct
- (i.e. i8042_tstc)
+ (i.e. rx51_kp_tstc)
VIDEO_GETC_FCT get char fct
- (i.e. i8042_getc)
- CONFIG_CONSOLE_CURSOR cursor drawing on/off
- (requires blink timer
- cf. i8042.c)
- CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
- CONFIG_CONSOLE_TIME display time/date info in
- upper right corner
- (requires CONFIG_CMD_DATE)
+ (i.e. rx51_kp_getc)
CONFIG_VIDEO_LOGO display Linux logo in
upper left corner
CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
bytes are output before the console is initialised, the
earlier bytes are discarded.
+ Note that when printing the buffer a copy is made on the
+ stack so CONFIG_PRE_CON_BUF_SZ must fit on the stack.
+
'Sane' compilers will generate smaller code if
CONFIG_PRE_CON_BUF_SZ is a power of 2
-- Safe printf() functions
- Define CONFIG_SYS_VSNPRINTF to compile in safe versions of
- the printf() functions. These are defined in
- include/vsprintf.h and include snprintf(), vsnprintf() and
- so on. Code size increase is approximately 300-500 bytes.
- If this option is not given then these functions will
- silently discard their buffer size argument - this means
- you are not getting any overflow checking in this case.
-
- Boot Delay: CONFIG_BOOTDELAY - in seconds
Delay before automatically booting the default image;
set to -1 to disable autoboot.
CONFIG_AUTOBOOT_PROMPT
CONFIG_AUTOBOOT_DELAY_STR
CONFIG_AUTOBOOT_STOP_STR
- CONFIG_AUTOBOOT_DELAY_STR2
- CONFIG_AUTOBOOT_STOP_STR2
CONFIG_ZERO_BOOTDELAY_CHECK
CONFIG_RESET_TO_RETRY
Monitor commands can be included or excluded
from the build by using the #include files
<config_cmd_all.h> and #undef'ing unwanted
- commands, or using <config_cmd_default.h>
- and augmenting with additional #define's
- for wanted commands.
+ commands, or adding #define's for wanted commands.
The default command configuration includes all commands
except those marked below with a "*".
SoC, then define this variable and provide board
specific code for the "hw_watchdog_reset" function.
+ CONFIG_AT91_HW_WDT_TIMEOUT
+ specify the timeout in seconds. default 2 seconds.
+
- U-Boot Version:
CONFIG_VERSION_VARIABLE
If this variable is defined, an environment variable
Management command for E1000 devices. When used on devices
with SPI support you can reprogram the EEPROM from U-Boot.
- CONFIG_E1000_FALLBACK_MAC
- default MAC for empty EEPROM after production.
-
CONFIG_EEPRO100
Support for Intel 82557/82559/82559ER chips.
Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
CONFIG_TPM
Support TPM devices.
- CONFIG_TPM_TIS_I2C
- Support for i2c bus TPM devices. Only one device
+ CONFIG_TPM_TIS_INFINEON
+ Support for Infineon i2c bus TPM devices. Only one device
per system is supported at this time.
- CONFIG_TPM_TIS_I2C_BUS_NUMBER
- Define the the i2c bus number for the TPM device
-
- CONFIG_TPM_TIS_I2C_SLAVE_ADDRESS
- Define the TPM's address on the i2c bus
-
CONFIG_TPM_TIS_I2C_BURST_LIMITATION
Define the burst count bytes upper limit
+ CONFIG_TPM_ST33ZP24
+ Support for STMicroelectronics TPM devices. Requires DM_TPM support.
+
+ CONFIG_TPM_ST33ZP24_I2C
+ Support for STMicroelectronics ST33ZP24 I2C devices.
+ Requires TPM_ST33ZP24 and I2C.
+
+ CONFIG_TPM_ST33ZP24_SPI
+ Support for STMicroelectronics ST33ZP24 SPI devices.
+ Requires TPM_ST33ZP24 and SPI.
+
CONFIG_TPM_ATMEL_TWI
Support for Atmel TWI TPM device. Requires I2C support.
key for the Replay Protection Memory Block partition in eMMC.
- USB Device Firmware Update (DFU) class support:
- CONFIG_DFU_FUNCTION
+ CONFIG_USB_FUNCTION_DFU
This enables the USB portion of the DFU USB class
CONFIG_CMD_DFU
sending again an USB request to the device.
- USB Device Android Fastboot support:
+ CONFIG_USB_FUNCTION_FASTBOOT
+ This enables the USB part of the fastboot gadget
+
CONFIG_CMD_FASTBOOT
This enables the command "fastboot" which enables the Android
fastboot mode for the platform's USB device. Fastboot is a USB
This enables support for booting images which use the Android
image format header.
- CONFIG_USB_FASTBOOT_BUF_ADDR
+ CONFIG_FASTBOOT_BUF_ADDR
The fastboot protocol requires a large memory buffer for
downloads. Define this to the starting RAM address to use for
downloaded images.
- CONFIG_USB_FASTBOOT_BUF_SIZE
+ CONFIG_FASTBOOT_BUF_SIZE
The fastboot protocol requires a large memory buffer for
downloads. This buffer should be as large as possible for a
platform. Define this to the size available RAM for fastboot.
a default value of 65536 will be defined.
- Keyboard Support:
- CONFIG_ISA_KEYBOARD
-
- Define this to enable standard (PC-Style) keyboard
- support
+ See Kconfig help for available keyboard drivers.
- CONFIG_I8042_KBD
- Standard PC keyboard driver with US (is default) and
- GERMAN key layout (switch via environment 'keymap=de') support.
- Export function i8042_kbd_init, i8042_tstc and i8042_getc
- for cfb_console. Supports cursor blinking.
+ CONFIG_KEYBOARD
- CONFIG_CROS_EC_KEYB
- Enables a Chrome OS keyboard using the CROS_EC interface.
- This uses CROS_EC to communicate with a second microcontroller
- which provides key scans on request.
+ Define this to enable a custom keyboard support.
+ This simply calls drv_keyboard_init() which must be
+ defined in your board-specific files. This option is deprecated
+ and is only used by novena. For new boards, use driver model
+ instead.
- Video support:
CONFIG_VIDEO
boot. See the documentation file README.video for a
description of this variable.
- CONFIG_VIDEO_VGA
-
- Enable the VGA video / BIOS for x86. The alternative if you
- are using coreboot is to use the coreboot frame buffer
- driver.
-
-
-- Keyboard Support:
- CONFIG_KEYBOARD
-
- Define this to enable a custom keyboard support.
- This simply calls drv_keyboard_init() which must be
- defined in your board-specific files.
- The only board using this so far is RBC823.
-
- LCD Support: CONFIG_LCD
Define this to enable LCD support (for output to LCD
CONFIG_LCD_ALIGNMENT
- Normally the LCD is page-aligned (tyically 4KB). If this is
+ Normally the LCD is page-aligned (typically 4KB). If this is
defined then the LCD will be aligned to this value instead.
For ARM it is sometimes useful to use MMU_SECTION_SIZE
here, since it is cheaper to change data cache settings on
the console jump but can help speed up operation when scrolling
is slow.
+ CONFIG_LCD_ROTATION
+
+ Sometimes, for example if the display is mounted in portrait
+ mode or even if it's mounted landscape but rotated by 180degree,
+ we need to rotate our content of the display relative to the
+ framebuffer, so that user can read the messages which are
+ printed out.
+ Once CONFIG_LCD_ROTATION is defined, the lcd_console will be
+ initialized with a given rotation from "vl_rot" out of
+ "vidinfo_t" which is provided by the board specific code.
+ The value for vl_rot is coded as following (matching to
+ fbcon=rotate:<n> linux-kernel commandline):
+ 0 = no rotation respectively 0 degree
+ 1 = 90 degree rotation
+ 2 = 180 degree rotation
+ 3 = 270 degree rotation
+
+ If CONFIG_LCD_ROTATION is not defined, the console will be
+ initialized with 0degree rotation.
+
CONFIG_LCD_BMP_RLE8
Support drawing of RLE8-compressed bitmaps on the LCD.
can be displayed via the splashscreen support or the
bmp command.
-- Do compresssing for memory range:
+- Do compressing for memory range:
CONFIG_CMD_ZIP
If this option is set, it would use zlib deflate method
Some PHY like Intel LXT971A need extra delay after
command issued before MII status register can be read
-- Ethernet address:
- CONFIG_ETHADDR
- CONFIG_ETH1ADDR
- CONFIG_ETH2ADDR
- CONFIG_ETH3ADDR
- CONFIG_ETH4ADDR
- CONFIG_ETH5ADDR
-
- Define a default value for Ethernet address to use
- for the respective Ethernet interface, in case this
- is not determined automatically.
-
- IP address:
CONFIG_IPADDR
- drivers/i2c/i2c_mxc.c
- activate this driver with CONFIG_SYS_I2C_MXC
+ - enable bus 1 with CONFIG_SYS_I2C_MXC_I2C1
+ - enable bus 2 with CONFIG_SYS_I2C_MXC_I2C2
+ - enable bus 3 with CONFIG_SYS_I2C_MXC_I2C3
+ - enable bus 4 with CONFIG_SYS_I2C_MXC_I2C4
- define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED
- define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE
- define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED
- define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE
- define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED
- define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE
- If thoses defines are not set, default value is 100000
+ - define speed for bus 4 with CONFIG_SYS_MXC_I2C4_SPEED
+ - define slave for bus 4 with CONFIG_SYS_MXC_I2C4_SLAVE
+ If those defines are not set, default value is 100000
for speed, and 0 for slave.
- drivers/i2c/rcar_i2c.c:
- CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4
- CONFIG_SYS_I2C_SH_BASE5 for setting the register channel 5
- CONFIG_SYS_I2C_SH_SPEED5 for for the speed channel 5
- - CONFIF_SYS_I2C_SH_NUM_CONTROLLERS for nummber of i2c buses
+ - CONFIG_SYS_I2C_SH_NUM_CONTROLLERS for number of i2c buses
- drivers/i2c/omap24xx_i2c.c
- activate this driver with CONFIG_SYS_I2C_OMAP24XX
- CONFIG_SYS_I2C_IHS_CH3 activate hardware channel 3
- CONFIG_SYS_I2C_IHS_SPEED_3 speed channel 3
- CONFIG_SYS_I2C_IHS_SLAVE_3 slave addr channel 3
+ - activate dual channel with CONFIG_SYS_I2C_IHS_DUAL
+ - CONFIG_SYS_I2C_IHS_SPEED_0_1 speed channel 0_1
+ - CONFIG_SYS_I2C_IHS_SLAVE_0_1 slave addr channel 0_1
+ - CONFIG_SYS_I2C_IHS_SPEED_1_1 speed channel 1_1
+ - CONFIG_SYS_I2C_IHS_SLAVE_1_1 slave addr channel 1_1
+ - CONFIG_SYS_I2C_IHS_SPEED_2_1 speed channel 2_1
+ - CONFIG_SYS_I2C_IHS_SLAVE_2_1 slave addr channel 2_1
+ - CONFIG_SYS_I2C_IHS_SPEED_3_1 speed channel 3_1
+ - CONFIG_SYS_I2C_IHS_SLAVE_3_1 slave addr channel 3_1
additional defines:
CONFIG_SYS_NUM_I2C_BUSES
- Hold the number of i2c busses you want to use. If you
+ Hold the number of i2c buses you want to use. If you
don't use/have i2c muxes on your i2c bus, this
is equal to CONFIG_SYS_NUM_I2C_ADAPTERS, and you can
omit this define.
define.
CONFIG_SYS_I2C_BUSES
- hold a list of busses you want to use, only used if
+ hold a list of buses you want to use, only used if
CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example
a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and
CONFIG_SYS_NUM_I2C_BUSES = 9:
Enables the driver for SPI controller on SuperH. Currently
only SH7757 is supported.
- CONFIG_SPI_X
-
- Enables extended (16-bit) SPI EEPROM addressing.
- (symmetrical to CONFIG_I2C_X)
-
CONFIG_SOFT_SPI
Enables a software (bit-bang) SPI driver rather than
CONFIG_SYS_FPGA_WAIT_INIT
- Maximum time to wait for the INIT_B line to deassert
- after PROB_B has been deasserted during a Virtex II
+ Maximum time to wait for the INIT_B line to de-assert
+ after PROB_B has been de-asserted during a Virtex II
FPGA configuration sequence. The default time is 500
ms.
CONFIG_SYS_FPGA_WAIT_BUSY
- Maximum time to wait for BUSY to deassert during
+ Maximum time to wait for BUSY to de-assert during
Virtex II FPGA configuration. The default is 5 ms.
CONFIG_SYS_FPGA_WAIT_CONFIG
completely disabled. Anybody can change or delete
these parameters.
- Alternatively, if you #define _both_ CONFIG_ETHADDR
- _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
+ Alternatively, if you define _both_ an ethaddr in the
+ default env _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
Ethernet address is installed in the environment,
which can be changed exactly ONCE by the user. [The
serial# is unaffected by this, i. e. it remains
of the backslashes before semicolons and special
symbols.
-- Commandline Editing and History:
+- Command Line Editing and History:
CONFIG_CMDLINE_EDITING
Enable editing and History functions for interactive
- commandline input operations
+ command line input operations
- Default Environment:
CONFIG_EXTRA_ENV_SETTINGS
CONFIG_DELAY_ENVIRONMENT
Normally the environment is loaded when the board is
- intialised so that it is available to U-Boot. This inhibits
+ initialised so that it is available to U-Boot. This inhibits
that so that the environment is not available until
explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL
this is instead controlled by the value of
/config/load-environment.
+- Parallel Flash support:
+ CONFIG_SYS_NO_FLASH
+
+ Traditionally U-boot was run on systems with parallel NOR
+ flash. This option is used to disable support for parallel NOR
+ flash. This option should be defined if the board does not have
+ parallel flash.
+
+ If this option is not defined one of the generic flash drivers
+ (e.g. CONFIG_FLASH_CFI_DRIVER or CONFIG_ST_SMI) must be
+ selected or the board must provide an implementation of the
+ flash API (see include/flash.h).
+
- DataFlash Support:
CONFIG_HAS_DATAFLASH
Define this option to include a destructive SPI flash
test ('sf test').
- CONFIG_SPI_FLASH_BAR Ban/Extended Addr Reg
-
- Define this option to use the Bank addr/Extended addr
- support on SPI flashes which has size > 16Mbytes.
-
CONFIG_SF_DUAL_FLASH Dual flash memories
Define this option to use dual flash support where two flash
memories can be connected with a given cs line.
- currently Xilinx Zynq qspi support these type of connections.
-
- CONFIG_SYS_SPI_ST_ENABLE_WP_PIN
- enable the W#/Vpp signal to disable writing to the status
- register on ST MICRON flashes like the N25Q128.
- The status register write enable/disable bit, combined with
- the W#/VPP signal provides hardware data protection for the
- device as follows: When the enable/disable bit is set to 1,
- and the W#/VPP signal is driven LOW, the status register
- nonvolatile bits become read-only and the WRITE STATUS REGISTER
- operation will not execute. The only way to exit this
- hardware-protected mode is to drive W#/VPP HIGH.
+ Currently Xilinx Zynq qspi supports these type of connections.
- SystemACE Support:
CONFIG_SYSTEMACE
Enable the hash verify command (hash -v). This adds to code
size a little.
- CONFIG_SHA1 - support SHA1 hashing
- CONFIG_SHA256 - support SHA256 hashing
+ CONFIG_SHA1 - This option enables support of hashing using SHA1
+ algorithm. The hash is calculated in software.
+ CONFIG_SHA256 - This option enables support of hashing using
+ SHA256 algorithm. The hash is calculated in software.
+ CONFIG_SHA_HW_ACCEL - This option enables hardware acceleration
+ for SHA1/SHA256 hashing.
+ This affects the 'hash' command and also the
+ hash_lookup_algo() function.
+ CONFIG_SHA_PROG_HW_ACCEL - This option enables
+ hardware-acceleration for SHA1/SHA256 progressive hashing.
+ Data can be streamed in a block at a time and the hashing
+ is performed in hardware.
Note: There is also a sha1sum command, which should perhaps
be deprecated in favour of 'hash sha1'.
This enables the RSA algorithm used for FIT image verification
in U-Boot. See doc/uImage.FIT/signature.txt for more information.
+ The Modular Exponentiation algorithm in RSA is implemented using
+ driver model. So CONFIG_DM needs to be enabled by default for this
+ library to function.
+
The signing part is build into mkimage regardless of this
- option.
+ option. The software based modular exponentiation is built into
+ mkimage irrespective of this option.
- bootcount support:
CONFIG_BOOTCOUNT_LIMIT
example, some LED's) on your board. At the moment,
the following checkpoints are implemented:
-- Detailed boot stage timing
- CONFIG_BOOTSTAGE
- Define this option to get detailed timing of each stage
- of the boot process.
-
- CONFIG_BOOTSTAGE_USER_COUNT
- This is the number of available user bootstage records.
- Each time you call bootstage_mark(BOOTSTAGE_ID_ALLOC, ...)
- a new ID will be allocated from this stash. If you exceed
- the limit, recording will stop.
-
- CONFIG_BOOTSTAGE_REPORT
- Define this to print a report before boot, similar to this:
-
- Timer summary in microseconds:
- Mark Elapsed Stage
- 0 0 reset
- 3,575,678 3,575,678 board_init_f start
- 3,575,695 17 arch_cpu_init A9
- 3,575,777 82 arch_cpu_init done
- 3,659,598 83,821 board_init_r start
- 3,910,375 250,777 main_loop
- 29,916,167 26,005,792 bootm_start
- 30,361,327 445,160 start_kernel
-
- CONFIG_CMD_BOOTSTAGE
- Add a 'bootstage' command which supports printing a report
- and un/stashing of bootstage data.
-
- CONFIG_BOOTSTAGE_FDT
- Stash the bootstage information in the FDT. A root 'bootstage'
- node is created with each bootstage id as a child. Each child
- has a 'name' property and either 'mark' containing the
- mark time in microsecond, or 'accum' containing the
- accumulated time for that bootstage id in microseconds.
- For example:
-
- bootstage {
- 154 {
- name = "board_init_f";
- mark = <3575678>;
- };
- 170 {
- name = "lcd";
- accum = <33482>;
- };
- };
-
- Code in the Linux kernel can find this in /proc/devicetree.
Legacy uImage format:
65 net/eth.c Ethernet found.
-80 common/cmd_net.c usage wrong
- 80 common/cmd_net.c before calling NetLoop()
- -81 common/cmd_net.c some error in NetLoop() occurred
- 81 common/cmd_net.c NetLoop() back without error
+ 80 common/cmd_net.c before calling net_loop()
+ -81 common/cmd_net.c some error in net_loop() occurred
+ 81 common/cmd_net.c net_loop() back without error
-82 common/cmd_net.c size == 0 (File with size 0 loaded)
82 common/cmd_net.c trying automatic boot
83 common/cmd_net.c running "source" command
CONFIG_FIT_SIGNATURE
This option enables signature verification of FIT uImages,
- using a hash signed and verified using RSA. See
- doc/uImage.FIT/signature.txt for more details.
+ using a hash signed and verified using RSA. If
+ CONFIG_SHA_PROG_HW_ACCEL is defined, i.e support for progressive
+ hashing is available using hardware, RSA library will use it.
+ See doc/uImage.FIT/signature.txt for more details.
WARNING: When relying on signed FIT images with required
signature check the legacy image format is default
Adds the MTD partitioning infrastructure from the Linux
kernel. Needed for UBI support.
- CONFIG_MTD_NAND_VERIFY_WRITE
- verify if the written data is correct reread.
-
- UBI support
CONFIG_CMD_UBI
without a fastmap.
default: 0
+ CONFIG_MTD_UBI_FM_DEBUG
+ Enable UBI fastmap debug
+ default: 0
+
- UBIFS support
CONFIG_CMD_UBIFS
CONFIG_SPL_STACK
Adress of the start of the stack SPL will use
+ CONFIG_SPL_PANIC_ON_RAW_IMAGE
+ When defined, SPL will panic() if the image it has
+ loaded does not have a signature.
+ Defining this is useful when code which loads images
+ in SPL cannot guarantee that absolutely all read errors
+ will be caught.
+ An example is the LPC32XX MLC NAND driver, which will
+ consider that a completely unreadable NAND block is bad,
+ and thus should be skipped silently.
+
CONFIG_SPL_RELOC_STACK
Adress of the start of the stack SPL will use after
relocation. If unspecified, this is equal to
CONFIG_SYS_SPL_MALLOC_START
Starting address of the malloc pool used in SPL.
+ When this option is set the full malloc is used in SPL and
+ it is set up by spl_init() and before that, the simple malloc()
+ can be used if CONFIG_SYS_MALLOC_F is defined.
CONFIG_SYS_SPL_MALLOC_SIZE
The size of the malloc pool used in SPL.
CONFIG_SYS_NAND_HW_ECC_OOBFIRST
Define this if you need to first read the OOB and then the
- data. This is used for example on davinci plattforms.
+ data. This is used, for example, on davinci platforms.
CONFIG_SPL_OMAP3_ID_NAND
Support for an OMAP3-specific set of functions to return the
- RTS/CTS Flow control enable:
CONFIG_HWFLOW
-- Modem debug support:
- CONFIG_MODEM_SUPPORT_DEBUG
-
- Enables debugging stuff (char screen[1024], dbg())
- for modem support. Useful only with BDI2000.
-
- Interrupt support (PPC):
There are common interrupt_init() and timer_interrupt()
Scratch address used by the alternate memory test
You only need to set this if address zero isn't writeable
-- CONFIG_SYS_MEM_TOP_HIDE (PPC only):
+- CONFIG_SYS_MEM_RESERVE_SECURE
+ If defined, the size of CONFIG_SYS_MEM_RESERVE_SECURE memory
+ is substracted from total RAM and won't be reported to OS.
+ This memory can be used as secure memory. A variable
+ gd->secure_ram is used to track the location. In systems
+ the RAM base is not zero, or RAM is divided into banks,
+ this variable needs to be recalcuated to get the address.
+
+- CONFIG_SYS_MEM_TOP_HIDE:
If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
this specified memory area will get subtracted from the top
(end) of RAM and won't get "touched" at all by U-Boot. By
This feature allocates regions with increasing addresses
within the region. calloc() is supported, but realloc()
is not available. free() is supported but does nothing.
- The memory will be freed (or in fact just forgotton) when
+ The memory will be freed (or in fact just forgotten) when
U-Boot relocates itself.
Pre-relocation malloc() is only supported on ARM and sandbox
boards which do not use the full malloc in SPL (which is
enabled with CONFIG_SYS_SPL_MALLOC_START).
+- CONFIG_SYS_NONCACHED_MEMORY:
+ Size of non-cached memory area. This area of memory will be
+ typically located right below the malloc() area and mapped
+ uncached in the MMU. This is useful for drivers that would
+ otherwise require a lot of explicit cache maintenance. For
+ some drivers it's also impossible to properly maintain the
+ cache. For example if the regions that need to be flushed
+ are not a multiple of the cache-line size, *and* padding
+ cannot be allocated between the regions to align them (i.e.
+ if the HW requires a contiguous array of regions, and the
+ size of each region is not cache-aligned), then a flush of
+ one region may result in overwriting data that hardware has
+ written to another region in the same cache-line. This can
+ happen for example in network drivers where descriptors for
+ buffers are typically smaller than the CPU cache-line (e.g.
+ 16 bytes vs. 32 or 64 bytes).
+
+ Non-cached memory is only supported on 32-bit ARM at present.
+
- CONFIG_SYS_BOOTM_LEN:
Normally compressed uImages are limited to an
uncompressed size of 8 MBytes. If this is not enough,
The format of the list is:
type_attribute = [s|d|x|b|i|m]
- access_atribute = [a|r|o|c]
- attributes = type_attribute[access_atribute]
+ access_attribute = [a|r|o|c]
+ attributes = type_attribute[access_attribute]
entry = variable_name[:attributes]
list = entry[,list]
- CONFIG_ENV_FLAGS_LIST_DEFAULT
Define this to a list (string) to define the ".flags"
- envirnoment variable in the default or embedded environment.
+ environment variable in the default or embedded environment.
- CONFIG_ENV_FLAGS_LIST_STATIC
Define this to a list (string) to define validation that
list, simply add an entry for the same variable name to the
".flags" variable.
+ If CONFIG_REGEX is defined, the variable_name above is evaluated as a
+ regular expression. This allows multiple variables to define the same
+ flags without explicitly listing them for each variable.
+
- CONFIG_ENV_ACCESS_IGNORE_FORCE
If defined, don't allow the -f switch to env set override variable
access flags.
to this new framework over time. Defining this will disable the
arch/foo/lib/board.c file and use common/board_f.c and
common/board_r.c instead. To use this option your architecture
- must support it (i.e. must define __HAVE_ARCH_GENERIC_BOARD in
- its config.mk file). If you find problems enabling this option on
- your board please report the problem and send patches!
+ must support it (i.e. must select HAVE_GENERIC_BOARD in arch/Kconfig).
+ If you find problems enabling this option on your board please report
+ the problem and send patches!
- CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC (OMAP only)
This is set by OMAP boards for the max time that reset should
be asserted. See doc/README.omap-reset-time for details on how
- the value can be calulated on a given board.
+ the value can be calculated on a given board.
- CONFIG_USE_STDINT
If stdint.h is available with your toolchain you can define this
provision.
BE CAREFUL! The first access to the environment happens quite early
-in U-Boot initalization (when we try to get the setting of for the
+in U-Boot initialization (when we try to get the setting of for the
console baudrate). You *MUST* have mapped your NVRAM area then, or
U-Boot will hang.
If defined, specified the chip address of the EEPROM device.
The default address is zero.
+ - CONFIG_SYS_I2C_EEPROM_BUS:
+ If defined, specified the i2c bus of the EEPROM device.
+
- CONFIG_SYS_EEPROM_PAGE_WRITE_BITS:
If defined, the number of bits used to address bytes in a
single page in the EEPROM device. A 64 byte page, for example
table, or the whole device D if has no partition
table.
- "D:auto": first partition in device D with bootable flag set.
- If none, first valid paratition in device D. If no
+ If none, first valid partition in device D. If no
partition table then means device D.
- FAT_ENV_FILE:
It's a string of the FAT file name. This file use to store the
- envrionment.
+ environment.
- CONFIG_FAT_WRITE:
- This should be defined. Otherwise it cannot save the envrionment file.
+ This should be defined. Otherwise it cannot save the environment file.
- CONFIG_ENV_IS_IN_MMC:
if CONFIG_SYS_FDC_HW_INIT is defined, then the function
fdc_hw_init() is called at the beginning of the FDC
setup. fdc_hw_init() must be provided by the board
- source code. It is used to make hardware dependant
+ source code. It is used to make hardware-dependent
initializations.
- CONFIG_IDE_AHB:
When software is doing ATA command and data transfer to
IDE devices through IDE-AHB controller, some additional
registers accessing to these kind of IDE-AHB controller
- is requierd.
+ is required.
- CONFIG_SYS_IMMR: Physical address of the Internal Memory.
DO NOT CHANGE unless you know exactly what you're
required.
- CONFIG_PCI_ENUM_ONLY
- Only scan through and get the devices on the busses.
+ Only scan through and get the devices on the buses.
Don't do any setup work, presumably because someone or
something has already done it, and we don't need to do it
a second time. Useful for platforms that are pre-booted
- CONFIG_FSL_DDR_INTERACTIVE
Enable interactive DDR debugging. See doc/README.fsl-ddr.
+- CONFIG_FSL_DDR_SYNC_REFRESH
+ Enable sync of refresh for multiple controllers.
+
+- CONFIG_FSL_DDR_BIST
+ Enable built-in memory test for Freescale DDR controllers.
+
- CONFIG_SYS_83XX_DDR_USES_CS0
Only for 83xx systems. If specified, then DDR should
be configured using CS0 and CS1 instead of CS2 and CS3.
normal addressable memory via the LBC. CONFIG_SYS_LS_MC_FW_ADDR is the
virtual address in NOR flash.
+Freescale Layerscape Debug Server Support:
+-------------------------------------------
+The Freescale Layerscape Debug Server Support supports the loading of
+"Debug Server firmware" and triggering SP boot-rom.
+This firmware often needs to be loaded during U-Boot booting.
+
+- CONFIG_FSL_DEBUG_SERVER
+ Enable the Debug Server for Layerscape SoCs.
+
+- CONFIG_SYS_DEBUG_SERVER_DRAM_BLOCK_MIN_SIZE
+ Define minimum DDR size required for debug server image
+
+- CONFIG_SYS_MC_RSV_MEM_ALIGN
+ Define alignment of reserved memory MC requires
+
+Reproducible builds
+-------------------
+
+In order to achieve reproducible builds, timestamps used in the U-Boot build
+process have to be set to a fixed value.
+
+This is done using the SOURCE_DATE_EPOCH environment variable.
+SOURCE_DATE_EPOCH is to be set on the build host's shell, not as a configuration
+option for U-Boot or an environment variable in U-Boot.
+
+SOURCE_DATE_EPOCH should be set to a number of seconds since the epoch, in UTC.
+
Building the Software:
======================
to port U-Boot to your hardware platform. To do this, follow these
steps:
-1. Add a new configuration option for your board to the toplevel
- "boards.cfg" file, using the existing entries as examples.
- Follow the instructions there to keep the boards in order.
-2. Create a new directory to hold your board specific code. Add any
+1. Create a new directory to hold your board specific code. Add any
files you need. In your board directory, you will need at least
- the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
-3. Create a new configuration file "include/configs/<board>.h" for
- your board
+ the "Makefile" and a "<board>.c".
+2. Create a new configuration file "include/configs/<board>.h" for
+ your board.
3. If you're porting U-Boot to a new CPU, then also create a new
directory to hold your CPU specific code. Add any files you need.
4. Run "make <board>_defconfig" with your new name.
npe_ucode - set load address for the NPE microcode
- silent_linux - If set then linux will be told to boot silently, by
+ silent_linux - If set then Linux will be told to boot silently, by
changing the console to be empty. If "yes" it will be
made silent. If "no" it will not be made silent. If
unset, then it will be made silent if the U-Boot console
is silent.
- tftpsrcport - If this is set, the value is used for TFTP's
+ tftpsrcp - If this is set, the value is used for TFTP's
UDP source port.
- tftpdstport - If this is set, the value is used for TFTP's UDP
+ tftpdstp - If this is set, the value is used for TFTP's UDP
destination port instead of the Well Know Port 69.
tftpblocksize - Block size to use for TFTP transfers; if not set,
faster in networks with high packet loss rates or
with unreliable TFTP servers.
+ tftptimeoutcountmax - maximum count of TFTP timeouts (no
+ unit, minimum value = 0). Defines how many timeouts
+ can happen during a single file transfer before that
+ transfer is aborted. The default is 10, and 0 means
+ 'no timeouts allowed'. Increasing this value may help
+ downloads succeed with high packet loss rates, or with
+ unreliable TFTP servers or client hardware.
+
vlan - When set to a value < 4095 the traffic over
Ethernet is encapsulated/received over 802.1q
VLAN tagged frames.
flash or offset in NAND flash.
*Note* - these variables don't have to be defined for all boards, some
-boards currenlty use other variables for these purposes, and some
+boards currently use other variables for these purposes, and some
boards use these variables for other purposes.
Image File Name RAM Address Flash Location
---------------------------------------------
For some environment variables, the behavior of u-boot needs to change
-when their values are changed. This functionailty allows functions to
+when their values are changed. This functionality allows functions to
be associated with arbitrary variables. On creation, overwrite, or
deletion, the callback will provide the opportunity for some side
effect to happen or for the change to be rejected.
with the same list format above. Any association in ".callbacks" will
override any association in the static list. You can define
CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the
-".callbacks" envirnoment variable in the default or embedded environment.
+".callbacks" environment variable in the default or embedded environment.
+
+If CONFIG_REGEX is defined, the variable_name above is evaluated as a
+regular expression. This allows multiple variables to be connected to
+the same callback without explicitly listing them all out.
Command Line Parsing:
warning is printed.
o If neither SROM nor the environment contain a MAC address, an error
- is raised.
+ is raised. If CONFIG_NET_RANDOM_ETHADDR is defined, then in this case
+ a random, locally-assigned MAC is used.
If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
will be programmed into hardware as part of the initialization process. This
option). Given an image built by mkimage, the dumpimage extracts a "data file"
from the image:
- tools/dumpimage -i image -p position data_file
- -i ==> extract from the 'image' a specific 'data_file', \
- indexed by 'position'
+ tools/dumpimage -i image -T type -p position data_file
+ -i ==> extract from the 'image' a specific 'data_file'
+ -T ==> set image type to 'type'
+ -p ==> 'position' (starting at 0) of the 'data_file' inside the 'image'
Installing a Linux Image:
* Initialized global data (data segment) is read-only. Do not attempt
to write it.
-* Do not use any uninitialized global data (or implicitely initialized
+* Do not use any uninitialized global data (or implicitly initialized
as zero data - BSS segment) at all - this is undefined, initiali-
zation is performed later (when relocating to RAM).
that.
Having only the stack as writable memory limits means we cannot use
-normal global data to share information beween the code. But it
+normal global data to share information between the code. But it
turned out that the implementation of U-Boot can be greatly
simplified by making a global data structure (gd_t) available to all
functions. We could pass a pointer to this data as argument to _all_
In the reset configuration, U-Boot starts at the reset entry point
(on most PowerPC systems at address 0x00000100). Because of the reset
-configuration for CS0# this is a mirror of the onboard Flash memory.
+configuration for CS0# this is a mirror of the on board Flash memory.
To be able to re-map memory U-Boot then jumps to its link address.
To be able to implement the initialization code in C, a (small!)
initial stack is set up in the internal Dual Ported RAM (in case CPUs
Source files originating from a different project (for example the
MTD subsystem) are generally exempt from these guidelines and are not
-reformated to ease subsequent migration to newer versions of those
+reformatted to ease subsequent migration to newer versions of those
sources.
Please note that U-Boot is implemented in C (and to some small parts in
* A CHANGELOG entry as plaintext (separate from the patch)
-* For major contributions, your entry to the CREDITS file
+* For major contributions, add a MAINTAINERS file with your
+ information and associated file and directory references.
* When you add support for a new board, don't forget to add a
maintainer e-mail address to the boards.cfg file, too.
projects / u-boot / blobdiff