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| -rw-r--r-- | doc/usage/index.rst | 3 | ||||
| -rw-r--r-- | doc/usage/sf.rst | 245 |
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diff --git a/doc/usage/environment.rst b/doc/usage/environment.rst new file mode 100644 index 0000000000..d295cc8987 --- /dev/null +++ b/doc/usage/environment.rst @@ -0,0 +1,465 @@ +.. SPDX-License-Identifier: GPL-2.0+ + +Environment Variables +===================== + +U-Boot supports user configuration using environment variables which +can be made persistent by saving to persistent storage, for example flash +memory. + +Environment variables are set using "env set" (alias "setenv"), printed using +"env print" (alias "printenv"), and saved to persistent storage using +"env save" (alias "saveenv"). Using "env set" +without a value can be used to delete a variable from the +environment. As long as you don't save the environment, you are +working with an in-memory copy. In case the Flash area containing the +environment is erased by accident, a default environment is provided. + +Some configuration is controlled by Environment Variables, so that setting the +variable can adjust the behaviour of U-Boot (e.g. autoboot delay, autoloading +from tftp). + +Text-based Environment +---------------------- + +The default environment for a board is created using a `.env` environment file +using a simple text format. The base filename for this is defined by +`CONFIG_ENV_SOURCE_FILE`, or `CONFIG_SYS_BOARD` if that is empty. + +The file must be in the board directory and have a .env extension, so +assuming that there is a board vendor, the resulting filename is therefore:: + + board/<vendor>/<board>/<CONFIG_ENV_SOURCE_FILE>.env + +or:: + + board/<vendor>/<board>/<CONFIG_SYS_BOARD>.env + +This is a plain text file where you can type your environment variables in +the form `var=value`. Blank lines and multi-line variables are supported. +The conversion script looks for a line that starts in column 1 with a string +and has an equals sign immediately afterwards. Spaces before the = are not +permitted. It is a good idea to indent your scripts so that only the 'var=' +appears at the start of a line. + +To add additional text to a variable you can use `var+=value`. This text is +merged into the variable during the make process and made available as a +single value to U-Boot. Variables can contain `+` characters but in the unlikely +event that you want to have a variable name ending in plus, put a backslash +before the `+` so that the script knows you are not adding to an existing +variable but assigning to a new one:: + + maximum\+=value + +This file can include C-style comments. Blank lines and multi-line +variables are supported, and you can use normal C preprocessor directives +and CONFIG defines from your board config also. + +For example, for snapper9260 you would create a text file called +`board/bluewater/snapper9260.env` containing the environment text. + +Example:: + + stdout=serial + #ifdef CONFIG_LCD + stdout+=,lcd + #endif + bootcmd= + /* U-Boot script for booting */ + + if [ -z ${tftpserverip} ]; then + echo "Use 'setenv tftpserverip a.b.c.d' to set IP address." + fi + + usb start; setenv autoload n; bootp; + tftpboot ${tftpserverip}: + bootm + failed= + /* Print a message when boot fails */ + echo CONFIG_SYS_BOARD boot failed - please check your image + echo Load address is CONFIG_SYS_LOAD_ADDR + +If CONFIG_ENV_SOURCE_FILE is empty and the default filename is not present, then +the old-style C environment is used instead. See below. + +Old-style C environment +----------------------- + +Traditionally, the default environment is created in `include/env_default.h`, +and can be augmented by various `CONFIG` defines. See that file for details. In +particular you can define `CONFIG_EXTRA_ENV_SETTINGS` in your board file +to add environment variables. + +Board maintainers are encouraged to migrate to the text-based environment as it +is easier to maintain. The distro-board script still requires the old-style +environment but work is underway to address this. + + +List of environment variables +----------------------------- + +Some device configuration options can be set using environment variables. In +many cases the value in the default environment comes from a CONFIG option - see +`include/env_default.h`) for this. + +This is most-likely not complete: + +baudrate + Used to set the baudrate of the UART - it defaults to CONFIG_BAUDRATE (which + defaults to 115200). + +bootdelay + Delay before automatically running bootcmd. During this time the user + can choose to enter the shell (or the boot menu if + CONFIG_AUTOBOOT_MENU_SHOW=y): + + - 0 to autoboot with no delay, but you can stop it by key input. + - -1 to disable autoboot. + - -2 to autoboot with no delay and not check for abort + + The default value is defined by CONFIG_BOOTDELAY. + The value of 'bootdelay' is overridden by the /config/bootdelay value in + the device-tree if CONFIG_OF_CONTROL=y. + Does it really make sense that the devicetree overrides the user setting? + +bootcmd + The command that is run if the user does not enter the shell during the + boot delay. + +bootargs + Command line arguments passed when booting an operating system or binary + image + +bootfile + Name of the image to load with TFTP + +bootm_low + Memory range available for image processing in the bootm + command can be restricted. This variable is given as + a hexadecimal number and defines lowest address allowed + for use by the bootm command. See also "bootm_size" + environment variable. Address defined by "bootm_low" is + also the base of the initial memory mapping for the Linux + kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and + bootm_mapsize. + +bootm_mapsize + Size of the initial memory mapping for the Linux kernel. + This variable is given as a hexadecimal number and it + defines the size of the memory region starting at base + address bootm_low that is accessible by the Linux kernel + during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used + as the default value if it is defined, and bootm_size is + used otherwise. + +bootm_size + Memory range available for image processing in the bootm + command can be restricted. This variable is given as + a hexadecimal number and defines the size of the region + allowed for use by the bootm command. See also "bootm_low" + environment variable. + +bootstopkeysha256, bootdelaykey, bootstopkey + See README.autoboot + +updatefile + Location of the software update file on a TFTP server, used + by the automatic software update feature. Please refer to + documentation in doc/README.update for more details. + +autoload + if set to "no" (any string beginning with 'n'), + "bootp" and "dhcp" will just load perform a lookup of the + configuration from the BOOTP server, but not try to + load any image using TFTP or DHCP. + +autostart + if set to "yes", an image loaded using the "bootp", "dhcp", + "rarpboot", "tftpboot" or "diskboot" commands will + be automatically started (by internally calling + "bootm") + + If unset, or set to "1"/"yes"/"true" (case insensitive, just the first + character is enough), a standalone image + passed to the "bootm" command will be copied to the load address + (and eventually uncompressed), but NOT be started. + This can be used to load and uncompress arbitrary + data. + +fdt_high + if set this restricts the maximum address that the + flattened device tree will be copied into upon boot. + For example, if you have a system with 1 GB memory + at physical address 0x10000000, while Linux kernel + only recognizes the first 704 MB as low memory, you + may need to set fdt_high as 0x3C000000 to have the + device tree blob be copied to the maximum address + of the 704 MB low memory, so that Linux kernel can + access it during the boot procedure. + + If this is set to the special value 0xffffffff (32-bit machines) or + 0xffffffffffffffff (64-bit machines) then + the fdt will not be copied at all on boot. For this + to work it must reside in writable memory, have + sufficient padding on the end of it for u-boot to + add the information it needs into it, and the memory + must be accessible by the kernel. + +fdtcontroladdr + if set this is the address of the control flattened + device tree used by U-Boot when CONFIG_OF_CONTROL is + defined. + +initrd_high + restrict positioning of initrd images: + If this variable is not set, initrd images will be + copied to the highest possible address in RAM; this + is usually what you want since it allows for + maximum initrd size. If for some reason you want to + make sure that the initrd image is loaded below the + CONFIG_SYS_BOOTMAPSZ limit, you can set this environment + variable to a value of "no" or "off" or "0". + Alternatively, you can set it to a maximum upper + address to use (U-Boot will still check that it + does not overwrite the U-Boot stack and data). + + For instance, when you have a system with 16 MB + RAM, and want to reserve 4 MB from use by Linux, + you can do this by adding "mem=12M" to the value of + the "bootargs" variable. However, now you must make + sure that the initrd image is placed in the first + 12 MB as well - this can be done with:: + + setenv initrd_high 00c00000 + + If you set initrd_high to 0xffffffff (32-bit machines) or + 0xffffffffffffffff (64-bit machines), this is an + indication to U-Boot that all addresses are legal + for the Linux kernel, including addresses in flash + memory. In this case U-Boot will NOT COPY the + ramdisk at all. This may be useful to reduce the + boot time on your system, but requires that this + feature is supported by your Linux kernel. + +ipaddr + IP address; needed for tftpboot command + +loadaddr + Default load address for commands like "bootp", + "rarpboot", "tftpboot", "loadb" or "diskboot" + +loads_echo + see CONFIG_LOADS_ECHO + +serverip + TFTP server IP address; needed for tftpboot command + +bootretry + see CONFIG_BOOT_RETRY_TIME + +bootdelaykey + see CONFIG_AUTOBOOT_DELAY_STR + +bootstopkey + see CONFIG_AUTOBOOT_STOP_STR + +ethprime + controls which network interface is used first. + +ethact + controls which interface is currently active. + For example you can do the following:: + + => setenv ethact FEC + => ping 192.168.0.1 # traffic sent on FEC + => setenv ethact SCC + => ping 10.0.0.1 # traffic sent on SCC + +ethrotate + When set to "no" U-Boot does not go through all + available network interfaces. + It just stays at the currently selected interface. When unset or set to + anything other than "no", U-Boot does go through all + available network interfaces. + +netretry + When set to "no" each network operation will + either succeed or fail without retrying. + When set to "once" the network operation will + fail when all the available network interfaces + are tried once without success. + Useful on scripts which control the retry operation + themselves. + +silent_linux + If set then Linux will be told to boot silently, by + adding 'console=' to its command line. 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. + +tftpsrcp + If this is set, the value is used for TFTP's + UDP source port. + +tftpdstp + If this is set, the value is used for TFTP's UDP + destination port instead of the default port 69. + +tftpblocksize + Block size to use for TFTP transfers; if not set, + we use the TFTP server's default block size + +tftptimeout + Retransmission timeout for TFTP packets (in milli- + seconds, minimum value is 1000 = 1 second). Defines + when a packet is considered to be lost so it has to + be retransmitted. The default is 5000 = 5 seconds. + Lowering this value may make downloads succeed + 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. + +tftpwindowsize + if this is set, the value is used for TFTP's + window size as described by RFC 7440. + This means the count of blocks we can receive before + sending ack to server. + +vlan + When set to a value < 4095 the traffic over + Ethernet is encapsulated/received over 802.1q + VLAN tagged frames. + + Note: This appears not to be used in U-Boot. See `README.VLAN`. + +bootpretryperiod + Period during which BOOTP/DHCP sends retries. + Unsigned value, in milliseconds. If not set, the period will + be either the default (28000), or a value based on + CONFIG_NET_RETRY_COUNT, if defined. This value has + precedence over the valu based on CONFIG_NET_RETRY_COUNT. + +memmatches + Number of matches found by the last 'ms' command, in hex + +memaddr + Address of the last match found by the 'ms' command, in hex, + or 0 if none + +mempos + Index position of the last match found by the 'ms' command, + in units of the size (.b, .w, .l) of the search + +zbootbase + (x86 only) Base address of the bzImage 'setup' block + +zbootaddr + (x86 only) Address of the loaded bzImage, typically + BZIMAGE_LOAD_ADDR which is 0x100000 + + +Image locations +--------------- + +The following image location variables contain the location of images +used in booting. The "Image" column gives the role of the image and is +not an environment variable name. The other columns are environment +variable names. "File Name" gives the name of the file on a TFTP +server, "RAM Address" gives the location in RAM the image will be +loaded to, and "Flash Location" gives the image's address in NOR +flash or offset in NAND flash. + +*Note* - these variables don't have to be defined for all boards, some +boards currently use other variables for these purposes, and some +boards use these variables for other purposes. + +Also note that most of these variables are just a commonly used set of variable +names, used in some other variable definitions, but are not hard-coded anywhere +in U-Boot code. + +================= ============== ================ ============== +Image File Name RAM Address Flash Location +================= ============== ================ ============== +u-boot u-boot u-boot_addr_r u-boot_addr +Linux kernel bootfile kernel_addr_r kernel_addr +device tree blob fdtfile fdt_addr_r fdt_addr +ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr +================= ============== ================ ============== + + +Automatically updated variables +------------------------------- + +The following environment variables may be used and automatically +updated by the network boot commands ("bootp" and "rarpboot"), +depending the information provided by your boot server: + +========= =================================================== +Variable Notes +========= =================================================== +bootfile see above +dnsip IP address of your Domain Name Server +dnsip2 IP address of your secondary Domain Name Server +gatewayip IP address of the Gateway (Router) to use +hostname Target hostname +ipaddr See above +netmask Subnet Mask +rootpath Pathname of the root filesystem on the NFS server +serverip see above +========= =================================================== + + +Special environment variables +----------------------------- + +There are two special Environment Variables: + +serial# + contains hardware identification information such as type string and/or + serial number +ethaddr + Ethernet address. If CONFIG_REGEX=y, also eth*addr (where * is an integer). + +These variables can be set only once (usually during manufacturing of +the board). U-Boot refuses to delete or overwrite these variables +once they have been set, unless CONFIG_ENV_OVERWRITE is enabled in the board +configuration. + +Also: + +ver + Contains the U-Boot version string as printed + with the "version" command. This variable is + readonly (see CONFIG_VERSION_VARIABLE). + +Please note that changes to some configuration parameters may take +only effect after the next boot (yes, that's just like Windows). + + +External environment file +------------------------- + +The `CONFIG_USE_DEFAULT_ENV_FILE` option provides a way to bypass the +environment generation in U-Boot. If enabled, then `CONFIG_DEFAULT_ENV_FILE` +provides the name of a file which is converted into the environment, +completely bypassing the standard environment variables in `env_default.h`. + +The format is the same as accepted by the mkenvimage tool, with lines containing +key=value pairs. Blank lines and lines beginning with # are ignored. + +Future work may unify this feature with the text-based environment, perhaps +moving the contents of `env_default.h` to a text file. + +Implementation +-------------- + +See :doc:`../develop/environment` for internal development details. diff --git a/doc/usage/index.rst b/doc/usage/index.rst index 356f2a5618..3905540735 100644 --- a/doc/usage/index.rst +++ b/doc/usage/index.rst @@ -5,11 +5,13 @@ Use U-Boot :maxdepth: 1 dfu + environment fdt_overlays fit netconsole partitions cmdline + environment Shell commands -------------- @@ -43,6 +45,7 @@ Shell commands qfw reset sbi + sf scp03 setexpr size diff --git a/doc/usage/sf.rst b/doc/usage/sf.rst new file mode 100644 index 0000000000..71bd1be517 --- /dev/null +++ b/doc/usage/sf.rst @@ -0,0 +1,245 @@ +.. SPDX-License-Identifier: GPL-2.0+: + +sf command +========== + +Synopis +------- + +:: + + sf probe [[[<bus>:]<cs>] [<hz> [<mode>]]] + sf read <addr> <offset>|<partition> <len> + sf write <addr> <offset>|<partition> <len> + sf erase <offset>|<partition> <len> + sf update <addr> <offset>|<partition> <len> + sf protect lock|unlock <sector> <len> + sf test <offset>|<partition> <len> + +Description +----------- + +The *sf* command is used to access SPI flash, supporting read/write/erase and +a few other functions. + +Probe +----- + +The flash must first be probed with *sf probe* before any of the other +subcommands can be used. All of the parameters are optional: + +bus + SPI bus number containing the SPI-flash chip, e.g. 0. If you don't know + the number, you can use 'dm uclass' to see all the spi devices, + and check the value for 'seq' for each one (here 0 and 2):: + + uclass 89: spi + 0 spi@0 @ 05484960, seq 0 + 1 spi@1 @ 05484b40, seq 2 + +cs + SPI chip-select to use for the chip. This is often 0 and can be omitted, + but in some cases multiple slaves are attached to a SPI controller, + selected by a chip-select line for each one. + +hz + Speed of the SPI bus in hertz. This normally defaults to 100000, i.e. + 100KHz, which is very slow. Note that if the device exists in the + device tree, there might be a speed provided there, in which case this + setting is ignored. + +mode + SPI mode to use: + + ===== ================ + Mode Meaning + ===== ================ + 0 CPOL=0, CPHA=0 + 1 CPOL=0, CPHA=1 + 2 CPOL=1, CPHA=0 + 3 CPOL=1, CPHA=1 + ===== ================ + + Clock phase (CPHA) 0 means that data is transferred (sampled) on the + first clock edge; 1 means the second. + + Clock polarity (CPOL) controls the idle state of the clock, 0 for low, + 1 for high. + The active state is the opposite of idle. + + You may find this `SPI documentation`_ useful. + +Parameters for other subcommands (described below) are as follows: + +addr + Memory address to start transfer + +offset + Flash offset to start transfer + +partition + If the parameter is not numeric, it is assumed to be a partition + description in the format <dev_type><dev_num>,<part_num> which is not + covered here. This requires CONFIG_CMD_MTDPARTS. + +len + Number of bytes to transfer + +Read +~~~~ + +Use *sf read* to read from SPI flash to memory. The read will fail if an +attempt is made to read past the end of the flash. + + +Write +~~~~~ + +Use *sf write* to write from memory to SPI flash. The SPI flash should be +erased first, since otherwise the result is undefined. + +The write will fail if an attempt is made to read past the end of the flash. + + +Erase +~~~~~ + +Use *sf erase* to erase a region of SPI flash. The erase will fail if any part +of the region to be erased is protected or lies past the end of the flash. It +may also fail if the start offset or length are not aligned to an erase region +(e.g. 256 bytes). + + +Update +~~~~~~ + +Use *sf update* to automatically erase and update a region of SPI flash from +memory. This works a sector at a time (typical 4KB or 64KB). For each +sector it first checks if the sector already has the right data. If so it is +skipped. If not, the sector is erased and the new data written. Note that if +the length is not a multiple of the erase size, the space after the data in +the last sector will be erased. If the offset does not start at the beginning +of an erase block, the operation will fail. + +Speed statistics are shown including the number of bytes that were already +correct. + + +Protect +~~~~~~~ + +SPI-flash chips often have a protection feature where the chip is split up into +regions which can be locked or unlocked. With *sf protect* it is possible to +change these settings, if supported by the driver. + +lock|unlock + Selects whether to lock or unlock the sectors + +<sector> + Start sector number to lock/unlock. This may be the byte offset or some + other value, depending on the chip. + +<len> + Number of bytes to lock/unlock + + +Test +~~~~ + +A convenient and fast *sf test* subcommand provides a way to check that SPI +flash is working as expected. This works in four stages: + + * erase - erases the entire region + * check - checks that the region is erased + * write - writes a test pattern to the region, consisting of the U-Boot code + * read - reads back the test pattern to check that it was written correctly + +Memory is allocated for two buffers, each <len> bytes in size. At typical +size is 64KB to 1MB. The offset and size must be aligned to an erase boundary. + +Note that this test will fail if any part of the SPI flash is write-protected. + + +Examples +-------- + +This first example uses sandbox:: + + => sf probe + SF: Detected m25p16 with page size 256 Bytes, erase size 64 KiB, total 2 MiB + => sf read 1000 1100 80000 + device 0 offset 0x1100, size 0x80000 + SF: 524288 bytes @ 0x1100 Read: OK + => md 1000 + 00001000: edfe0dd0 f33a0000 78000000 84250000 ......:....x..%. + 00001010: 28000000 11000000 10000000 00000000 ...(............ + 00001020: 6f050000 0c250000 00000000 00000000 ...o..%......... + 00001030: 00000000 00000000 00000000 00000000 ................ + 00001040: 00000000 00000000 00000000 00000000 ................ + 00001050: 00000000 00000000 00000000 00000000 ................ + 00001060: 00000000 00000000 00000000 00000000 ................ + 00001070: 00000000 00000000 01000000 00000000 ................ + 00001080: 03000000 04000000 00000000 01000000 ................ + 00001090: 03000000 04000000 0f000000 01000000 ................ + 000010a0: 03000000 08000000 1b000000 646e6173 ............sand + 000010b0: 00786f62 03000000 08000000 21000000 box............! + 000010c0: 646e6173 00786f62 01000000 61696c61 sandbox.....alia + 000010d0: 00736573 03000000 07000000 2c000000 ses............, + 000010e0: 6332692f 00003040 03000000 07000000 /i2c@0.......... + 000010f0: 31000000 6963702f 00003040 03000000 ...1/pci@0...... + => sf erase 0 80000 + SF: 524288 bytes @ 0x0 Erased: OK + => sf read 1000 1100 80000 + device 0 offset 0x1100, size 0x80000 + SF: 524288 bytes @ 0x1100 Read: OK + => md 1000 + 00001000: ffffffff ffffffff ffffffff ffffffff ................ + 00001010: ffffffff ffffffff ffffffff ffffffff ................ + 00001020: ffffffff ffffffff ffffffff ffffffff ................ + 00001030: ffffffff ffffffff ffffffff ffffffff ................ + 00001040: ffffffff ffffffff ffffffff ffffffff ................ + 00001050: ffffffff ffffffff ffffffff ffffffff ................ + 00001060: ffffffff ffffffff ffffffff ffffffff ................ + 00001070: ffffffff ffffffff ffffffff ffffffff ................ + 00001080: ffffffff ffffffff ffffffff ffffffff ................ + 00001090: ffffffff ffffffff ffffffff ffffffff ................ + 000010a0: ffffffff ffffffff ffffffff ffffffff ................ + 000010b0: ffffffff ffffffff ffffffff ffffffff ................ + 000010c0: ffffffff ffffffff ffffffff ffffffff ................ + 000010d0: ffffffff ffffffff ffffffff ffffffff ................ + 000010e0: ffffffff ffffffff ffffffff ffffffff ................ + 000010f0: ffffffff ffffffff ffffffff ffffffff ................ + +This second example is running on coral, an x86 Chromebook:: + + => sf probe + SF: Detected w25q128fw with page size 256 Bytes, erase size 4 KiB, total 16 MiB + => sf erase 300000 80000 + SF: 524288 bytes @ 0x300000 Erased: OK + => sf update 1110000 300000 80000 + device 0 offset 0x300000, size 0x80000 + 524288 bytes written, 0 bytes skipped in 0.457s, speed 1164578 B/s + + # This does nothing as the flash is already updated + => sf update 1110000 300000 80000 + device 0 offset 0x300000, size 0x80000 + 0 bytes written, 524288 bytes skipped in 0.196s, speed 2684354 B/s + => sf test 00000 80000 # try a protected region + SPI flash test: + Erase failed (err = -5) + Test failed + => sf test 800000 80000 + SPI flash test: + 0 erase: 18 ticks, 28444 KiB/s 227.552 Mbps + 1 check: 192 ticks, 2666 KiB/s 21.328 Mbps + 2 write: 227 ticks, 2255 KiB/s 18.040 Mbps + 3 read: 189 ticks, 2708 KiB/s 21.664 Mbps + Test passed + 0 erase: 18 ticks, 28444 KiB/s 227.552 Mbps + 1 check: 192 ticks, 2666 KiB/s 21.328 Mbps + 2 write: 227 ticks, 2255 KiB/s 18.040 Mbps + 3 read: 189 ticks, 2708 KiB/s 21.664 Mbps + + +.. _SPI documentation: + https://en.wikipedia.org/wiki/Serial_Peripheral_Interface |