SPI NOR 框架¶

如何建议添加新的闪存¶

大多数 SPI NOR 闪存都符合 JEDEC JESD216 串行闪存可发现参数 (SFDP) 标准。SFDP 在一组标准的内部只读参数表中描述了串行闪存设备的功能和特性。

SPI NOR 驱动程序查询 SFDP 表，以确定闪存的参数和设置。如果闪存定义了 SFDP 表，则很可能根本不需要闪存条目，而是依赖于通用闪存驱动程序，该驱动程序仅基于其 SFDP 数据探测闪存。只需在设备树中指定“jedec,spi-nor”兼容即可。

在某些情况下，您需要定义一个显式的闪存条目。当闪存具有 SFDP 表未涵盖的设置或支持（例如，块保护）时，或者当闪存包含损坏的 SFDP 数据时，通常会发生这种情况。如果属于后者，则需要实现 spi_nor_fixups 钩子，以便使用正确的值修改 SFDP 参数。

最低测试要求¶

执行以下所有测试，并在提交的注释部分中粘贴它们，在 --- 标记之后。

指定用于测试闪存的控制器，并指定闪存的运行频率，例如

This flash is populated on the X board and was tested at Y
frequency using the Z (put compatible) SPI controller.

转储 sysfs 条目并打印 md5/sha1/sha256 SFDP 校验和

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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root@1:~# sha256sum /sys/bus/spi/devices/spi0.0/spi-nor/sfdp
428f34d0461876f189ac97f93e68a05fa6428c6650b3b7baf736a921e5898ed1  /sys/bus/spi/devices/spi0.0/spi-nor/sfdp

请使用 xxd -p 转储 SFDP 表。它使我们能够进行反向操作，并使用 xxd -rp 将十六进制转储转换为二进制。接受使用 hexdump -Cv 转储 SFDP 数据，但不太理想。

转储 debugfs 数据

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  ] |

使用 mtd-utils 并验证擦除、读取和页面编程操作是否正常工作

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

如果闪存默认擦除，并且之前的擦除被忽略，我们将无法捕获它，因此请再次测试擦除

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

转储其他一些相关数据

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

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SPI NOR 框架¶

如何建议添加新的闪存¶

最低测试要求¶