/nios2 Files generic to Altera NIOS2 architecture
/openrisc Files generic to OpenRISC architecture
/powerpc Files generic to PowerPC architecture
+ /riscv Files generic to RISC-V architecture
/sandbox Files generic to HW-independent "sandbox"
/sh Files generic to SH architecture
/x86 Files generic to x86 architecture
kernel configuration options. The intention is to make it easier to
build a config tool - later.
+- ARM Platform Bus Type(CCI):
+ CoreLink Cache Coherent Interconnect (CCI) is ARM BUS which
+ provides full cache coherency between two clusters of multi-core
+ CPUs and I/O coherency for devices and I/O masters
+
+ CONFIG_SYS_FSL_HAS_CCI400
+
+ Defined For SoC that has cache coherent interconnect
+ CCN-400
+
+ CONFIG_SYS_FSL_HAS_CCN504
+
+ Defined for SoC that has cache coherent interconnect CCN-504
The following options need to be configured:
supported, core will start to execute uboot when wakes up.
- Generic CPU options:
- CONFIG_SYS_GENERIC_GLOBAL_DATA
- Defines global data is initialized in generic board board_init_f().
- If this macro is defined, global data is created and cleared in
- generic board board_init_f(). Without this macro, architecture/board
- should initialize global data before calling board_init_f().
-
CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN
Defines the endianess of the CPU. Implementation of those
when no character is read on the console interface
within "Boot Delay" after reset.
- CONFIG_BOOTARGS
- This can be used to pass arguments to the bootm
- command. The value of CONFIG_BOOTARGS goes into the
- environment value "bootargs".
-
CONFIG_RAMBOOT and CONFIG_NFSBOOT
The value of these goes into the environment as
"ramboot" and "nfsboot" respectively, and can be used
RAM and NFS.
- Bootcount:
- CONFIG_BOOTCOUNT_LIMIT
- Implements a mechanism for detecting a repeating reboot
- cycle, see:
- http://www.denx.de/wiki/view/DULG/UBootBootCountLimit
-
CONFIG_BOOTCOUNT_ENV
If no softreset save registers are found on the hardware
"bootcount" is stored in the environment. To prevent a
Select one of the baudrates listed in
CONFIG_SYS_BAUDRATE_TABLE, see below.
-- Monitor Functions:
- 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 adding #define's for wanted commands.
-
- The default command configuration includes all commands
- except those marked below with a "*".
-
- CONFIG_CMD_AES AES 128 CBC encrypt/decrypt
- CONFIG_CMD_ASKENV * ask for env variable
- CONFIG_CMD_BDI bdinfo
- CONFIG_CMD_BOOTD bootd
- CONFIG_CMD_BOOTI * ARM64 Linux kernel Image support
- CONFIG_CMD_CACHE * icache, dcache
- CONFIG_CMD_CONSOLE coninfo
- CONFIG_CMD_DHCP * DHCP support
- CONFIG_CMD_DIAG * Diagnostics
- CONFIG_CMD_ECHO echo arguments
- CONFIG_CMD_EDITENV edit env variable
- CONFIG_CMD_ELF * bootelf, bootvx
- CONFIG_CMD_ENV_EXISTS * check existence of env variable
- CONFIG_CMD_EXPORTENV * export the environment
- CONFIG_CMD_EXT2 * ext2 command support
- CONFIG_CMD_EXT4 * ext4 command support
- CONFIG_CMD_FS_GENERIC * filesystem commands (e.g. load, ls)
- that work for multiple fs types
- CONFIG_CMD_FS_UUID * Look up a filesystem UUID
- CONFIG_CMD_SAVEENV saveenv
- CONFIG_CMD_FLASH flinfo, erase, protect
- CONFIG_CMD_FPGA FPGA device initialization support
- CONFIG_CMD_GO * the 'go' command (exec code)
- CONFIG_CMD_GREPENV * search environment
- CONFIG_CMD_I2C * I2C serial bus support
- CONFIG_CMD_IMI iminfo
- CONFIG_CMD_IMLS List all images found in NOR flash
- CONFIG_CMD_IMLS_NAND * List all images found in NAND flash
- CONFIG_CMD_IMPORTENV * import an environment
- CONFIG_CMD_INI * import data from an ini file into the env
- CONFIG_CMD_ITEST Integer/string test of 2 values
- CONFIG_CMD_LDRINFO * ldrinfo (display Blackfin loader)
- CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration
- (169.254.*.*)
- CONFIG_CMD_LOADB loadb
- CONFIG_CMD_LOADS loads
- CONFIG_CMD_MD5SUM * print md5 message digest
- (requires CONFIG_CMD_MEMORY and CONFIG_MD5)
- CONFIG_CMD_MEMINFO * Display detailed memory information
- CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
- loop, loopw
- CONFIG_CMD_MEMTEST * mtest
- CONFIG_CMD_MISC Misc functions like sleep etc
- CONFIG_CMD_MMC * MMC memory mapped support
- CONFIG_CMD_MII * MII utility commands
- CONFIG_CMD_MTDPARTS * MTD partition support
- CONFIG_CMD_NAND * NAND support
- CONFIG_CMD_NET bootp, tftpboot, rarpboot
- CONFIG_CMD_NFS NFS support
- CONFIG_CMD_PCA953X * PCA953x I2C gpio commands
- CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command
- CONFIG_CMD_PCI * pciinfo
- CONFIG_CMD_PCMCIA * PCMCIA support
- CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network
- host
- CONFIG_CMD_PORTIO * Port I/O
- CONFIG_CMD_READ * Read raw data from partition
- CONFIG_CMD_REGINFO * Register dump
- CONFIG_CMD_RUN run command in env variable
- CONFIG_CMD_SANDBOX * sb command to access sandbox features
- CONFIG_CMD_SAVES * save S record dump
- CONFIG_CMD_SDRAM * print SDRAM configuration information
- (requires CONFIG_CMD_I2C)
- CONFIG_CMD_SF * Read/write/erase SPI NOR flash
- CONFIG_CMD_SOFTSWITCH * Soft switch setting command for BF60x
- CONFIG_CMD_SOURCE "source" command Support
- CONFIG_CMD_SPI * SPI serial bus support
- CONFIG_CMD_TFTPSRV * TFTP transfer in server mode
- CONFIG_CMD_TFTPPUT * TFTP put command (upload)
- CONFIG_CMD_TIME * run command and report execution time (ARM specific)
- CONFIG_CMD_TIMER * access to the system tick timer
- CONFIG_CMD_USB * USB support
- CONFIG_CMD_CDP * Cisco Discover Protocol support
- CONFIG_CMD_MFSL * Microblaze FSL support
- CONFIG_CMD_XIMG Load part of Multi Image
- CONFIG_CMD_UUID * Generate random UUID or GUID string
-
- EXAMPLE: If you want all functions except of network
- support you can write:
-
- #include "config_cmd_all.h"
- #undef CONFIG_CMD_NET
-
- Other Commands:
- fdt (flattened device tree) command: CONFIG_OF_LIBFDT
-
- Note: Don't enable the "icache" and "dcache" commands
- (configuration option CONFIG_CMD_CACHE) unless you know
- what you (and your U-Boot users) are doing. Data
- cache cannot be enabled on systems like the
- 8xx (where accesses to the IMMR region must be
- uncached), and it cannot be disabled on all other
- systems where we (mis-) use the data cache to hold an
- initial stack and some data.
-
-
- XXX - this list needs to get updated!
-
- Removal of commands
If no commands are needed to boot, you can disable
CONFIG_CMDLINE to remove them. In this case, the command line
binary in its image. This device tree file should be in the
board directory and called <soc>-<board>.dts. The binary file
is then picked up in board_init_f() and made available through
- the global data structure as gd->blob.
+ the global data structure as gd->fdt_blob.
CONFIG_OF_SEPARATE
If this variable is defined, U-Boot will build a device tree
Allow generic access to the SPI bus on the Intel 8257x, for
example with the "sspi" command.
- CONFIG_CMD_E1000
- Management command for E1000 devices. When used on devices
- with SPI support you can reprogram the EEPROM from U-Boot.
-
CONFIG_EEPRO100
Support for Intel 82557/82559/82559ER chips.
Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
control registers. This behavior won't affect the
correctnessof 10/100 link speed update.
- CONFIG_SMC911X
- Support for SMSC's LAN911x and LAN921x chips
-
- CONFIG_SMC911X_BASE
- Define this to hold the physical address
- of the device (I/O space)
-
- CONFIG_SMC911X_32_BIT
- Define this if data bus is 32 bits
-
- CONFIG_SMC911X_16_BIT
- Define this if data bus is 16 bits. If your processor
- automatically converts one 32 bit word to two 16 bit
- words you may also try CONFIG_SMC911X_32_BIT.
-
CONFIG_SH_ETHER
Support for Renesas on-chip Ethernet controller
to. Contemporary x86 systems usually map it at
0xfed40000.
- CONFIG_CMD_TPM
- Add tpm monitor functions.
- Requires CONFIG_TPM. If CONFIG_TPM_AUTH_SESSIONS is set, also
- provides monitor access to authorized functions.
-
CONFIG_TPM
Define this to enable the TPM support library which provides
functional interfaces to some TPM commands.
CONFIG_USB_FUNCTION_DFU
This enables the USB portion of the DFU USB class
- CONFIG_CMD_DFU
- This enables the command "dfu" which is used to have
- U-Boot create a DFU class device via USB. This command
- requires that the "dfu_alt_info" environment variable be
- set and define the alt settings to expose to the host.
-
CONFIG_DFU_MMC
This enables support for exposing (e)MMC devices via DFU.
entering dfuMANIFEST state. Host waits this timeout, before
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
- protocol for downloading images, flashing and device control
- used on Android devices.
- See doc/README.android-fastboot for more information.
-
- CONFIG_ANDROID_BOOT_IMAGE
- This enables support for booting images which use the Android
- image format header.
-
- 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_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.
-
- CONFIG_FASTBOOT_FLASH
- The fastboot protocol includes a "flash" command for writing
- the downloaded image to a non-volatile storage device. Define
- this to enable the "fastboot flash" command.
-
- CONFIG_FASTBOOT_FLASH_MMC_DEV
- The fastboot "flash" command requires additional information
- regarding the non-volatile storage device. Define this to
- the eMMC device that fastboot should use to store the image.
-
- CONFIG_FASTBOOT_GPT_NAME
- The fastboot "flash" command supports writing the downloaded
- image to the Protective MBR and the Primary GUID Partition
- Table. (Additionally, this downloaded image is post-processed
- to generate and write the Backup GUID Partition Table.)
- This occurs when the specified "partition name" on the
- "fastboot flash" command line matches this value.
- The default is "gpt" if undefined.
-
- CONFIG_FASTBOOT_MBR_NAME
- The fastboot "flash" command supports writing the downloaded
- image to DOS MBR.
- This occurs when the "partition name" specified on the
- "fastboot flash" command line matches this value.
- If not defined the default value "mbr" is used.
-
- Journaling Flash filesystem support:
CONFIG_JFFS2_NAND
Define these for a default partition on a NAND device
the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
be at least 4MB.
- CONFIG_LZO
-
- If this option is set, support for LZO compressed images
- is included.
-
- MII/PHY support:
CONFIG_PHY_ADDR
The clock frequency of the MII bus
- CONFIG_PHY_GIGE
-
- If this option is set, support for speed/duplex
- detection of gigabit PHY is included.
-
CONFIG_PHY_RESET_DELAY
Some PHY like Intel LXT971A need extra delay after
See doc/README.link-local for more information.
+ - MAC address from environment variables
+
+ FDT_SEQ_MACADDR_FROM_ENV
+
+ Fix-up device tree with MAC addresses fetched sequentially from
+ environment variables. This config work on assumption that
+ non-usable ethernet node of device-tree are either not present
+ or their status has been marked as "disabled".
+
- CDP Options:
CONFIG_CDP_DEVICE_ID
SPI EEPROM, also an instance works with Crystal A/D and
D/As on the SACSng board)
- CONFIG_SH_SPI
-
- Enables the driver for SPI controller on SuperH. Currently
- only SH7757 is supported.
-
CONFIG_SOFT_SPI
Enables a software (bit-bang) SPI driver rather than
Currently supported on some MPC8xxx processors. For an
example, see include/configs/mpc8349emds.h.
- CONFIG_MXC_SPI
-
- Enables the driver for the SPI controllers on i.MX and MXC
- SoCs. Currently i.MX31/35/51 are supported.
-
CONFIG_SYS_SPI_MXC_WAIT
Timeout for waiting until spi transfer completed.
default: (CONFIG_SYS_HZ/100) /* 10 ms */
currently only supports clearing the memory.
- Error Recovery:
- CONFIG_PANIC_HANG
-
- Define this variable to stop the system in case of a
- fatal error, so that you have to reset it manually.
- This is probably NOT a good idea for an embedded
- system where you want the system to reboot
- automatically as fast as possible, but it may be
- useful during development since you can try to debug
- the conditions that lead to the situation.
-
CONFIG_NET_RETRY_COUNT
This variable defines the number of retries for
this is instead controlled by the value of
/config/load-environment.
-- DataFlash Support:
- CONFIG_HAS_DATAFLASH
-
- Defining this option enables DataFlash features and
- allows to read/write in Dataflash via the standard
- commands cp, md...
-
- Serial Flash support
- CONFIG_CMD_SF
-
- Defining this option enables SPI flash commands
- 'sf probe/read/write/erase/update'.
-
- Usage requires an initial 'probe' to define the serial
+ Usage requires an initial 'sf probe' to define the serial
flash parameters, followed by read/write/erase/update
commands.
CONFIG_SF_DEFAULT_MODE (see include/spi.h)
CONFIG_SF_DEFAULT_SPEED in Hz
- CONFIG_CMD_SF_TEST
-
- Define this option to include a destructive SPI flash
- test ('sf test').
-
-- SystemACE Support:
- CONFIG_SYSTEMACE
-
- Adding this option adds support for Xilinx SystemACE
- chips attached via some sort of local bus. The address
- of the chip must also be defined in the
- CONFIG_SYS_SYSTEMACE_BASE macro. For example:
-
- #define CONFIG_SYSTEMACE
- #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000
-
- When SystemACE support is added, the "ace" device type
- becomes available to the fat commands, i.e. fatls.
- TFTP Fixed UDP Port:
CONFIG_TFTP_PORT
but sometimes that is not allowed.
- bootcount support:
- CONFIG_BOOTCOUNT_LIMIT
-
- This enables the bootcounter support, see:
- http://www.denx.de/wiki/DULG/UBootBootCountLimit
-
CONFIG_AT91SAM9XE
enable special bootcounter support on at91sam9xe based boards.
CONFIG_SOC_DA8XX
CONFIG_SYS_BOOTCOUNT_ADDR = i2c addr which is used for
the bootcounter.
CONFIG_BOOTCOUNT_ALEN = address len
+ CONFIG_BOOTCOUNT_EXT
+ enable support for the bootcounter in EXT filesystem
+ CONFIG_SYS_BOOTCOUNT_ADDR = RAM address used for read
+ and write.
+ CONFIG_SYS_BOOTCOUNT_EXT_INTERFACE = interface
+ CONFIG_SYS_BOOTCOUNT_EXT_DEVPART = device and part
+ CONFIG_SYS_BOOTCOUNT_EXT_NAME = filename
- Show boot progress:
CONFIG_SHOW_BOOT_PROGRESS
kernel. Needed for UBI support.
- UBI support
- CONFIG_CMD_UBI
-
- Adds commands for interacting with MTD partitions formatted
- with the UBI flash translation layer
-
- Requires also defining CONFIG_RBTREE
-
CONFIG_UBI_SILENCE_MSG
Make the verbose messages from UBI stop printing. This leaves
default: 0
- UBIFS support
- CONFIG_CMD_UBIFS
-
- Adds commands for interacting with UBI volumes formatted as
- UBIFS. UBIFS is read-only in u-boot.
-
- Requires UBI support as well as CONFIG_LZO
-
CONFIG_UBIFS_SILENCE_MSG
Make the verbose messages from UBIFS stop printing. This leaves
CONFIG_SYS_SPL_MALLOC_SIZE
The size of the malloc pool used in SPL.
- CONFIG_SPL_FRAMEWORK
- Enable the SPL framework under common/. This framework
- supports MMC, NAND and YMODEM loading of U-Boot and NAND
- NAND loading of the Linux Kernel.
-
CONFIG_SPL_OS_BOOT
Enable booting directly to an OS from SPL.
See also: doc/README.falcon
Define this if you need to first read the OOB and then the
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
- ID and MFR of the first attached NAND chip, if present.
-
CONFIG_SPL_RAM_DEVICE
Support for running image already present in ram, in SPL binary
Builds up envcrc with the target environment so that external utils
may easily extract it and embed it in final U-Boot images.
-- CONFIG_ENV_IS_IN_FLASH:
-
- Define this if the environment is in flash memory.
-
- a) The environment occupies one whole flash sector, which is
- "embedded" in the text segment with the U-Boot code. This
- happens usually with "bottom boot sector" or "top boot
- sector" type flash chips, which have several smaller
- sectors at the start or the end. For instance, such a
- layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
- such a case you would place the environment in one of the
- 4 kB sectors - with U-Boot code before and after it. With
- "top boot sector" type flash chips, you would put the
- environment in one of the last sectors, leaving a gap
- between U-Boot and the environment.
-
- - CONFIG_ENV_OFFSET:
-
- Offset of environment data (variable area) to the
- beginning of flash memory; for instance, with bottom boot
- type flash chips the second sector can be used: the offset
- for this sector is given here.
-
- CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE.
-
- - CONFIG_ENV_ADDR:
-
- This is just another way to specify the start address of
- the flash sector containing the environment (instead of
- CONFIG_ENV_OFFSET).
-
- - CONFIG_ENV_SECT_SIZE:
-
- Size of the sector containing the environment.
-
-
- b) Sometimes flash chips have few, equal sized, BIG sectors.
- In such a case you don't want to spend a whole sector for
- the environment.
-
- - CONFIG_ENV_SIZE:
-
- If you use this in combination with CONFIG_ENV_IS_IN_FLASH
- and CONFIG_ENV_SECT_SIZE, you can specify to use only a part
- of this flash sector for the environment. This saves
- memory for the RAM copy of the environment.
-
- It may also save flash memory if you decide to use this
- when your environment is "embedded" within U-Boot code,
- since then the remainder of the flash sector could be used
- for U-Boot code. It should be pointed out that this is
- STRONGLY DISCOURAGED from a robustness point of view:
- updating the environment in flash makes it always
- necessary to erase the WHOLE sector. If something goes
- wrong before the contents has been restored from a copy in
- RAM, your target system will be dead.
-
- - CONFIG_ENV_ADDR_REDUND
- CONFIG_ENV_SIZE_REDUND
-
- These settings describe a second storage area used to hold
- a redundant copy of the environment data, so that there is
- a valid backup copy in case there is a power failure during
- a "saveenv" operation.
-
-BE CAREFUL! Any changes to the flash layout, and some changes to the
-source code will make it necessary to adapt <board>/u-boot.lds*
-accordingly!
-
-
-- CONFIG_ENV_IS_IN_NVRAM:
-
- Define this if you have some non-volatile memory device
- (NVRAM, battery buffered SRAM) which you want to use for the
- environment.
-
- - CONFIG_ENV_ADDR:
- - CONFIG_ENV_SIZE:
-
- These two #defines are used to determine the memory area you
- want to use for environment. It is assumed that this memory
- can just be read and written to, without any special
- provision.
-
BE CAREFUL! The first access to the environment happens quite early
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
keep settings there always unmodified except somebody uses "saveenv"
to save the current settings.
-
-- CONFIG_ENV_IS_IN_EEPROM:
-
- Use this if you have an EEPROM or similar serial access
- device and a driver for it.
-
- - CONFIG_ENV_OFFSET:
- - CONFIG_ENV_SIZE:
-
- These two #defines specify the offset and size of the
- environment area within the total memory of your EEPROM.
-
- - CONFIG_SYS_I2C_EEPROM_ADDR:
- 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
- would require six bits.
-
- - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS:
- If defined, the number of milliseconds to delay between
- page writes. The default is zero milliseconds.
-
- - CONFIG_SYS_I2C_EEPROM_ADDR_LEN:
- The length in bytes of the EEPROM memory array address. Note
- that this is NOT the chip address length!
-
- - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW:
- EEPROM chips that implement "address overflow" are ones
- like Catalyst 24WC04/08/16 which has 9/10/11 bits of
- address and the extra bits end up in the "chip address" bit
- slots. This makes a 24WC08 (1Kbyte) chip look like four 256
- byte chips.
-
- Note that we consider the length of the address field to
- still be one byte because the extra address bits are hidden
- in the chip address.
-
- - CONFIG_SYS_EEPROM_SIZE:
- The size in bytes of the EEPROM device.
-
- - CONFIG_ENV_EEPROM_IS_ON_I2C
- define this, if you have I2C and SPI activated, and your
- EEPROM, which holds the environment, is on the I2C bus.
-
- - CONFIG_I2C_ENV_EEPROM_BUS
- if you have an Environment on an EEPROM reached over
- I2C muxes, you can define here, how to reach this
- EEPROM. For example:
-
- #define CONFIG_I2C_ENV_EEPROM_BUS 1
-
- EEPROM which holds the environment, is reached over
- a pca9547 i2c mux with address 0x70, channel 3.
-
-- CONFIG_ENV_IS_IN_DATAFLASH:
-
- Define this if you have a DataFlash memory device which you
- want to use for the environment.
-
- - CONFIG_ENV_OFFSET:
- - CONFIG_ENV_ADDR:
- - CONFIG_ENV_SIZE:
-
- These three #defines specify the offset and size of the
- environment area within the total memory of your DataFlash placed
- at the specified address.
-
-- CONFIG_ENV_IS_IN_SPI_FLASH:
-
- Define this if you have a SPI Flash memory device which you
- want to use for the environment.
-
- - CONFIG_ENV_OFFSET:
- - CONFIG_ENV_SIZE:
-
- These two #defines specify the offset and size of the
- environment area within the SPI Flash. CONFIG_ENV_OFFSET must be
- aligned to an erase sector boundary.
-
- - CONFIG_ENV_SECT_SIZE:
-
- Define the SPI flash's sector size.
-
- - CONFIG_ENV_OFFSET_REDUND (optional):
-
- This setting describes a second storage area of CONFIG_ENV_SIZE
- size used to hold a redundant copy of the environment data, so
- that there is a valid backup copy in case there is a power failure
- during a "saveenv" operation. CONFIG_ENV_OFFSET_REDUND must be
- aligned to an erase sector boundary.
-
- - CONFIG_ENV_SPI_BUS (optional):
- - CONFIG_ENV_SPI_CS (optional):
-
- Define the SPI bus and chip select. If not defined they will be 0.
-
- - CONFIG_ENV_SPI_MAX_HZ (optional):
-
- Define the SPI max work clock. If not defined then use 1MHz.
-
- - CONFIG_ENV_SPI_MODE (optional):
-
- Define the SPI work mode. If not defined then use SPI_MODE_3.
-
-- CONFIG_ENV_IS_IN_REMOTE:
-
- Define this if you have a remote memory space which you
- want to use for the local device's environment.
-
- - CONFIG_ENV_ADDR:
- - CONFIG_ENV_SIZE:
-
- These two #defines specify the address and size of the
- environment area within the remote memory space. The
- local device can get the environment from remote memory
- space by SRIO or PCIE links.
-
BE CAREFUL! For some special cases, the local device can not use
"saveenv" command. For example, the local device will get the
environment stored in a remote NOR flash by SRIO or PCIE link,
but it can not erase, write this NOR flash by SRIO or PCIE interface.
-- CONFIG_ENV_IS_IN_NAND:
-
- Define this if you have a NAND device which you want to use
- for the environment.
-
- - CONFIG_ENV_OFFSET:
- - CONFIG_ENV_SIZE:
-
- These two #defines specify the offset and size of the environment
- area within the first NAND device. CONFIG_ENV_OFFSET must be
- aligned to an erase block boundary.
-
- - CONFIG_ENV_OFFSET_REDUND (optional):
-
- This setting describes a second storage area of CONFIG_ENV_SIZE
- size used to hold a redundant copy of the environment data, so
- that there is a valid backup copy in case there is a power failure
- during a "saveenv" operation. CONFIG_ENV_OFFSET_REDUND must be
- aligned to an erase block boundary.
-
- - CONFIG_ENV_RANGE (optional):
-
- Specifies the length of the region in which the environment
- can be written. This should be a multiple of the NAND device's
- block size. Specifying a range with more erase blocks than
- are needed to hold CONFIG_ENV_SIZE allows bad blocks within
- the range to be avoided.
-
- - CONFIG_ENV_OFFSET_OOB (optional):
-
- Enables support for dynamically retrieving the offset of the
- environment from block zero's out-of-band data. The
- "nand env.oob" command can be used to record this offset.
- Currently, CONFIG_ENV_OFFSET_REDUND is not supported when
- using CONFIG_ENV_OFFSET_OOB.
-
- CONFIG_NAND_ENV_DST
Defines address in RAM to which the nand_spl code should copy the
environment. If redundant environment is used, it will be copied to
CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
-- CONFIG_ENV_IS_IN_UBI:
-
- Define this if you have an UBI volume that you want to use for the
- environment. This has the benefit of wear-leveling the environment
- accesses, which is important on NAND.
-
- - CONFIG_ENV_UBI_PART:
-
- Define this to a string that is the mtd partition containing the UBI.
-
- - CONFIG_ENV_UBI_VOLUME:
-
- Define this to the name of the volume that you want to store the
- environment in.
-
- - CONFIG_ENV_UBI_VOLUME_REDUND:
-
- Define this to the name of another volume to store a second copy of
- the environment in. This will enable redundant environments in UBI.
- It is assumed that both volumes are in the same MTD partition.
-
- - CONFIG_UBI_SILENCE_MSG
- - CONFIG_UBIFS_SILENCE_MSG
-
- You will probably want to define these to avoid a really noisy system
- when storing the env in UBI.
-
-- CONFIG_ENV_IS_IN_FAT:
- Define this if you want to use the FAT file system for the environment.
-
- - FAT_ENV_INTERFACE:
-
- Define this to a string that is the name of the block device.
-
- - FAT_ENV_DEVICE_AND_PART:
-
- Define this to a string to specify the partition of the device. It can
- be as following:
-
- "D:P", "D:0", "D", "D:" or "D:auto" (D, P are integers. And P >= 1)
- - "D:P": device D partition P. Error occurs if device D has no
- partition table.
- - "D:0": device D.
- - "D" or "D:": device D partition 1 if device D has partition
- 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 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
- environment.
-
- - CONFIG_FAT_WRITE:
- This must be enabled. Otherwise it cannot save the environment file.
-
-- CONFIG_ENV_IS_IN_MMC:
-
- Define this if you have an MMC device which you want to use for the
- environment.
-
- - CONFIG_SYS_MMC_ENV_DEV:
-
- Specifies which MMC device the environment is stored in.
-
- - CONFIG_SYS_MMC_ENV_PART (optional):
-
- Specifies which MMC partition the environment is stored in. If not
- set, defaults to partition 0, the user area. Common values might be
- 1 (first MMC boot partition), 2 (second MMC boot partition).
-
- - CONFIG_ENV_OFFSET:
- - CONFIG_ENV_SIZE:
-
- These two #defines specify the offset and size of the environment
- area within the specified MMC device.
-
- If offset is positive (the usual case), it is treated as relative to
- the start of the MMC partition. If offset is negative, it is treated
- as relative to the end of the MMC partition. This can be useful if
- your board may be fitted with different MMC devices, which have
- different sizes for the MMC partitions, and you always want the
- environment placed at the very end of the partition, to leave the
- maximum possible space before it, to store other data.
-
- These two values are in units of bytes, but must be aligned to an
- MMC sector boundary.
-
- - CONFIG_ENV_OFFSET_REDUND (optional):
-
- Specifies a second storage area, of CONFIG_ENV_SIZE size, used to
- hold a redundant copy of the environment data. This provides a
- valid backup copy in case the other copy is corrupted, e.g. due
- to a power failure during a "saveenv" operation.
-
- This value may also be positive or negative; this is handled in the
- same way as CONFIG_ENV_OFFSET.
-
- This value is also in units of bytes, but must also be aligned to
- an MMC sector boundary.
-
- - CONFIG_ENV_SIZE_REDUND (optional):
-
- This value need not be set, even when CONFIG_ENV_OFFSET_REDUND is
- set. If this value is set, it must be set to the same value as
- CONFIG_ENV_SIZE.
-
Please note that the environment is read-only until the monitor
has been relocated to RAM and a RAM copy of the environment has been
-created; also, when using EEPROM you will have to use getenv_f()
+created; also, when using EEPROM you will have to use env_get_f()
until then to read environment variables.
The environment is protected by a CRC32 checksum. Before the monitor
- CONFIG_LOOPW
Add the "loopw" memory command. This only takes effect if
- the memory commands are activated globally (CONFIG_CMD_MEM).
+ the memory commands are activated globally (CONFIG_CMD_MEMORY).
- CONFIG_MX_CYCLIC
Add the "mdc" and "mwc" memory commands. These are cyclic
This command will write 12345678 to address 100 all 10 ms.
This only takes effect if the memory commands are activated
- globally (CONFIG_CMD_MEM).
+ globally (CONFIG_CMD_MEMORY).
- CONFIG_SKIP_LOWLEVEL_INIT
- [ARM, NDS32, MIPS only] If this variable is defined, then certain
+ [ARM, NDS32, MIPS, RISC-V only] If this variable is defined, then certain
low level initializations (like setting up the memory
controller) are omitted and/or U-Boot does not
relocate itself into RAM.
Note that the command line "O=" setting overrides the KBUILD_OUTPUT environment
variable.
+User specific CPPFLAGS, AFLAGS and CFLAGS can be passed to the compiler by
+setting the according environment variables KCPPFLAGS, KAFLAGS and KCFLAGS.
+For example to treat all compiler warnings as errors:
+
+ make KCFLAGS=-Werror
Please be aware that the Makefiles assume you are using GNU make, so
for instance on NetBSD you might need to use "gmake" instead of
NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
or current versions of GCC may "optimize" the code too much.
+On RISC-V, the following registers are used:
+
+ x0: hard-wired zero (zero)
+ x1: return address (ra)
+ x2: stack pointer (sp)
+ x3: global pointer (gp)
+ x4: thread pointer (tp)
+ x5: link register (t0)
+ x8: frame pointer (fp)
+ x10-x11: arguments/return values (a0-1)
+ x12-x17: arguments (a2-7)
+ x28-31: temporaries (t3-6)
+ pc: program counter (pc)
+
+ ==> U-Boot will use gp to hold a pointer to the global data
+
Memory Management:
------------------
-----------------
All contributions to U-Boot should conform to the Linux kernel
-coding style; see the file "Documentation/CodingStyle" and the script
-"scripts/Lindent" in your Linux kernel source directory.
+coding style; see the kernel coding style guide at
+https://www.kernel.org/doc/html/latest/process/coding-style.html, and the
+script "scripts/Lindent" in your Linux kernel source directory.
Source files originating from a different project (for example the
MTD subsystem) are generally exempt from these guidelines and are not
Please see http://www.denx.de/wiki/U-Boot/Patches for details.
Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
-see http://lists.denx.de/mailman/listinfo/u-boot
+see https://lists.denx.de/listinfo/u-boot
When you send a patch, please include the following information with
it:
projects / people / ms / u-boot.git / blobdiff