From: Simon Glass Date: Sun, 19 Sep 2021 21:49:35 +0000 (-0600) Subject: sf: doc: Add documentation for the 'sf' command X-Git-Tag: v2022.07~227^2~25^2~17 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=1fb115e4d2a69118388e82af13b1159e102e539b;p=platform%2Fkernel%2Fu-boot.git sf: doc: Add documentation for the 'sf' command This command is fairly complicated so documentation is useful. Unfortunately I an not sure how the MTD side of things works and cannot find information about that. Signed-off-by: Simon Glass Acked-by: Pratyush Yadav Reviewed-by: Jagan Teki Acked-by: Heinrich Schuchardt --- diff --git a/doc/usage/index.rst b/doc/usage/index.rst index 04dea9f..3905540 100644 --- a/doc/usage/index.rst +++ b/doc/usage/index.rst @@ -45,6 +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 0000000..71bd1be --- /dev/null +++ b/doc/usage/sf.rst @@ -0,0 +1,245 @@ +.. SPDX-License-Identifier: GPL-2.0+: + +sf command +========== + +Synopis +------- + +:: + + sf probe [[[:]] [ []]] + sf read | + sf write | + sf erase | + sf update | + sf protect lock|unlock + sf test | + +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 , 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 + + + Start sector number to lock/unlock. This may be the byte offset or some + other value, depending on the chip. + + + 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 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