| ================= |
| SPI NOR framework |
| ================= |
| |
| How to propose a new flash addition |
| ----------------------------------- |
| |
| Most SPI NOR flashes comply with the JEDEC JESD216 |
| Serial Flash Discoverable Parameter (SFDP) standard. SFDP describes |
| the functional and feature capabilities of serial flash devices in a |
| standard set of internal read-only parameter tables. |
| |
| The SPI NOR driver queries the SFDP tables in order to determine the |
| flash's parameters and settings. If the flash defines the SFDP tables |
| it's likely that you won't need a flash entry at all, and instead |
| rely on the generic flash driver which probes the flash solely based |
| on its SFDP data. All one has to do is to specify the "jedec,spi-nor" |
| compatible in the device tree. |
| |
| There are cases however where you need to define an explicit flash |
| entry. This typically happens when the flash has settings or support |
| that is not covered by the SFDP tables (e.g. Block Protection), or |
| when the flash contains mangled SFDP data. If the later, one needs |
| to implement the ``spi_nor_fixups`` hooks in order to amend the SFDP |
| parameters with the correct values. |
| |
| Minimum testing requirements |
| ----------------------------- |
| |
| Do all the tests from below and paste them in the commit's comments |
| section, after the ``---`` marker. |
| |
| 1) Specify the controller that you used to test the flash and specify |
| the frequency at which the flash was operated, e.g.:: |
| |
| This flash is populated on the X board and was tested at Y |
| frequency using the Z (put compatible) SPI controller. |
| |
| 2) Dump the sysfs entries and print the md5/sha1/sha256 SFDP checksum:: |
| |
| root@1:~# cat /sys/bus/spi/devices/spi0.0/spi-nor/partname |
| sst26vf064b |
| root@1:~# cat /sys/bus/spi/devices/spi0.0/spi-nor/jedec_id |
| bf2643 |
| root@1:~# cat /sys/bus/spi/devices/spi0.0/spi-nor/manufacturer |
| sst |
| root@1:~# xxd -p /sys/bus/spi/devices/spi0.0/spi-nor/sfdp |
| 53464450060102ff00060110300000ff81000106000100ffbf0001180002 |
| 0001fffffffffffffffffffffffffffffffffd20f1ffffffff0344eb086b |
| 083b80bbfeffffffffff00ffffff440b0c200dd80fd810d820914824806f |
| 1d81ed0f773830b030b0f7ffffff29c25cfff030c080ffffffffffffffff |
| ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff |
| ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff |
| ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff |
| ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff |
| ffffffffffffffffffffffffffffffffff0004fff37f0000f57f0000f9ff |
| 7d00f57f0000f37f0000ffffffffffffffffffffffffffffffffffffffff |
| ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff |
| ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff |
| ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff |
| ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff |
| ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff |
| ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff |
| ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff |
| ffffbf2643ffb95ffdff30f260f332ff0a122346ff0f19320f1919ffffff |
| ffffffff00669938ff05013506040232b03072428de89888a585c09faf5a |
| ffff06ec060c0003080bffffffffff07ffff0202ff060300fdfd040700fc |
| 0300fefe0202070e |
| root@1:~# sha256sum /sys/bus/spi/devices/spi0.0/spi-nor/sfdp |
| 428f34d0461876f189ac97f93e68a05fa6428c6650b3b7baf736a921e5898ed1 /sys/bus/spi/devices/spi0.0/spi-nor/sfdp |
| |
| Please dump the SFDP tables using ``xxd -p``. It enables us to do |
| the reverse operation and convert the hexdump to binary with |
| ``xxd -rp``. Dumping the SFDP data with ``hexdump -Cv`` is accepted, |
| but less desirable. |
| |
| 3) Dump debugfs data:: |
| |
| root@1:~# cat /sys/kernel/debug/spi-nor/spi0.0/capabilities |
| Supported read modes by the flash |
| 1S-1S-1S |
| opcode 0x03 |
| mode cycles 0 |
| dummy cycles 0 |
| 1S-1S-1S (fast read) |
| opcode 0x0b |
| mode cycles 0 |
| dummy cycles 8 |
| 1S-1S-2S |
| opcode 0x3b |
| mode cycles 0 |
| dummy cycles 8 |
| 1S-2S-2S |
| opcode 0xbb |
| mode cycles 4 |
| dummy cycles 0 |
| 1S-1S-4S |
| opcode 0x6b |
| mode cycles 0 |
| dummy cycles 8 |
| 1S-4S-4S |
| opcode 0xeb |
| mode cycles 2 |
| dummy cycles 4 |
| 4S-4S-4S |
| opcode 0x0b |
| mode cycles 2 |
| dummy cycles 4 |
| |
| Supported page program modes by the flash |
| 1S-1S-1S |
| opcode 0x02 |
| |
| root@1:~# cat /sys/kernel/debug/spi-nor/spi0.0/params |
| name sst26vf064b |
| id bf 26 43 bf 26 43 |
| size 8.00 MiB |
| write size 1 |
| page size 256 |
| address nbytes 3 |
| flags HAS_LOCK | HAS_16BIT_SR | SOFT_RESET | SWP_IS_VOLATILE |
| |
| opcodes |
| read 0xeb |
| dummy cycles 6 |
| erase 0x20 |
| program 0x02 |
| 8D extension none |
| |
| protocols |
| read 1S-4S-4S |
| write 1S-1S-1S |
| register 1S-1S-1S |
| |
| erase commands |
| 20 (4.00 KiB) [0] |
| d8 (8.00 KiB) [1] |
| d8 (32.0 KiB) [2] |
| d8 (64.0 KiB) [3] |
| c7 (8.00 MiB) |
| |
| sector map |
| region (in hex) | erase mask | flags |
| ------------------+------------+---------- |
| 00000000-00007fff | [01 ] | |
| 00008000-0000ffff | [0 2 ] | |
| 00010000-007effff | [0 3] | |
| 007f0000-007f7fff | [0 2 ] | |
| 007f8000-007fffff | [01 ] | |
| |
| 4) Use `mtd-utils <https://git.infradead.org/mtd-utils.git>`__ |
| and verify that erase, read and page program operations work fine:: |
| |
| root@1:~# dd if=/dev/urandom of=./spi_test bs=1M count=2 |
| 2+0 records in |
| 2+0 records out |
| 2097152 bytes (2.1 MB, 2.0 MiB) copied, 0.848566 s, 2.5 MB/s |
| |
| root@1:~# mtd_debug erase /dev/mtd0 0 2097152 |
| Erased 2097152 bytes from address 0x00000000 in flash |
| |
| root@1:~# mtd_debug read /dev/mtd0 0 2097152 spi_read |
| Copied 2097152 bytes from address 0x00000000 in flash to spi_read |
| |
| root@1:~# hexdump spi_read |
| 0000000 ffff ffff ffff ffff ffff ffff ffff ffff |
| * |
| 0200000 |
| |
| root@1:~# sha256sum spi_read |
| 4bda3a28f4ffe603c0ec1258c0034d65a1a0d35ab7bd523a834608adabf03cc5 spi_read |
| |
| root@1:~# mtd_debug write /dev/mtd0 0 2097152 spi_test |
| Copied 2097152 bytes from spi_test to address 0x00000000 in flash |
| |
| root@1:~# mtd_debug read /dev/mtd0 0 2097152 spi_read |
| Copied 2097152 bytes from address 0x00000000 in flash to spi_read |
| |
| root@1:~# sha256sum spi* |
| c444216a6ba2a4a66cccd60a0dd062bce4b865dd52b200ef5e21838c4b899ac8 spi_read |
| c444216a6ba2a4a66cccd60a0dd062bce4b865dd52b200ef5e21838c4b899ac8 spi_test |
| |
| If the flash comes erased by default and the previous erase was ignored, |
| we won't catch it, thus test the erase again:: |
| |
| root@1:~# mtd_debug erase /dev/mtd0 0 2097152 |
| Erased 2097152 bytes from address 0x00000000 in flash |
| |
| root@1:~# mtd_debug read /dev/mtd0 0 2097152 spi_read |
| Copied 2097152 bytes from address 0x00000000 in flash to spi_read |
| |
| root@1:~# sha256sum spi* |
| 4bda3a28f4ffe603c0ec1258c0034d65a1a0d35ab7bd523a834608adabf03cc5 spi_read |
| c444216a6ba2a4a66cccd60a0dd062bce4b865dd52b200ef5e21838c4b899ac8 spi_test |
| |
| Dump some other relevant data:: |
| |
| root@1:~# mtd_debug info /dev/mtd0 |
| mtd.type = MTD_NORFLASH |
| mtd.flags = MTD_CAP_NORFLASH |
| mtd.size = 8388608 (8M) |
| mtd.erasesize = 4096 (4K) |
| mtd.writesize = 1 |
| mtd.oobsize = 0 |
| regions = 0 |
