[PATCH 25/25] mtd: spi-nor: winbond: Add support for W25Q25PW-M
From: Miquel Raynal
Date: Wed Sep 09 2026 - 14:05:29 EST
There is an ID collision with chips of same density from the JW family
(which it self conflicted with yet another family). Chips are very
similar in practice, it is mostly a matter of electrical differences
(mostly power consumption being lower) as well as the addition of inline
ECC capability.
16 bytes chunks are protected against single errors. In case a
non-aligned write happens, ECC is locally disabled until the next erase.
Another significant difference is that PW chips identify themselves as
supporting the new SFDP (rev F) QER field which forces an alternate
write SR2 opcode (0x31).
Signed-off-by: Miquel Raynal <miquel.raynal@xxxxxxxxxxx>
---
+ cat /sys/bus/spi/devices/spi0.0/spi-nor/jedec_id
ef8019
+ cat /sys/bus/spi/devices/spi0.0/spi-nor/manufacturer
winbond
+ xxd -p /sys/bus/spi/devices/spi0.0/spi-nor/sfdp
534644500a0101ff00080117800000ff84010102e00000ffffffffffffff
ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
ffffffffffffffffe520fbffffffff0f44eb086b083b42bbfeffffffffff
0000ffff44eb0c200f5210d80000142a010186e114c4e96376337a757a75
f7a4d55c39f66dffe970f9a50000000000002c0000000000f7f5ffff0f00
0000060d44bd27ed080dffffffffff8a00fe21ffdcff
+ sha256sum /sys/bus/spi/devices/spi0.0/spi-nor/sfdp
3361f4e84529b23aacc3cc1d41bcb36b2c3a0e42be019d71b586c952e03e6098 /sys/bus/spi/devices/spi0.0/spi-nor/sfdp
+ cat /sys/kernel/debug/spi-nor/spi0.0/capabilities
Supported read modes by the flash
1S-1S-1S
opcode 0x13
mode cycles 0
dummy cycles 0
1S-1S-2S
opcode 0x3c
mode cycles 0
dummy cycles 8
1S-2S-2S
opcode 0xbc
mode cycles 2
dummy cycles 2
1S-1S-4S
opcode 0x6c
mode cycles 0
dummy cycles 8
1S-4S-4S
opcode 0xec
mode cycles 2
dummy cycles 4
4S-4S-4S
opcode 0xec
mode cycles 2
dummy cycles 4
Supported page program modes by the flash
1S-1S-1S
opcode 0x12
1S-1S-4S
opcode 0x34
+ cat /sys/kernel/debug/spi-nor/spi0.0/params
name (null)
id ef 80 19 00 00 00
size 32.0 MiB
write size 16
page size 256
address nbytes 4
flags HAS_SR_TB | 4B_OPCODES | HAS_4BAIT | HAS_LOCK | HAS_SR_TB_BIT6 | HAS_4BIT_BP | SOFT_RESET | ECC | NO_WP | HAS_SR2_CMP_BIT6
opcodes
read 0xec
dummy cycles 6
erase 0xdc
program 0x34
8D extension repeat
protocols
read 1S-4S-4S
write 1S-1S-4S
register 1S-1S-1S
erase commands
21 (4.00 KiB) [1]
dc (64.0 KiB) [3]
c7 (32.0 MiB)
sector map
region (in hex) | erase mask | overlaid
------------------+------------+---------
00000000-01ffffff | [ 3] | no
locked sectors
region (in hex) | status | #sectors
------------------+----------+---------
00000000-01ffffff | unlocked | 512
+ dd 'if=/dev/urandom' 'of=./spi_test' 'bs=1M' 'count=2'
[ 7.216017] random: crng init done
2+0 records in
2+0 records out
+ mtd_debug erase /dev/mtd0 0 2097152
Erased 2097152 bytes from address 0x00000000 in flash
+ mtd_debug read /dev/mtd0 0 2097152 spi_read
[ 9.225266] spi_nor_read [1882] [ret: 0] SR3 0x4 @ offset 0x0
Copied 2097152 bytes from address 0x00000000 in flash to spi_read
+ hexdump spi_read
0000000 ffff ffff ffff ffff ffff ffff ffff ffff
*
0200000
+ sha256sum spi_read
4bda3a28f4ffe603c0ec1258c0034d65a1a0d35ab7bd523a834608adabf03cc5 spi_read
+ mtd_debug write /dev/mtd0 0 2097152 spi_test
Copied 2097152 bytes from spi_test to address 0x00000000 in flash
+ mtd_debug read /dev/mtd0 0 2097152 spi_read
[ 12.783730] spi_nor_read [1882] [ret: 0] SR3 0x4 @ offset 0x0
Copied 2097152 bytes from address 0x00000000 in flash to spi_read
+ sha256sum spi_read spi_test
51acf03d440fea3017e99b0dfd9711173044c57be0e2699221e969b6c02a2133 spi_read
51acf03d440fea3017e99b0dfd9711173044c57be0e2699221e969b6c02a2133 spi_test
+ mtd_debug erase /dev/mtd0 0 2097152
Erased 2097152 bytes from address 0x00000000 in flash
+ mtd_debug read /dev/mtd0 0 2097152 spi_read
[ 17.878349] spi_nor_read [1882] [ret: 0] SR3 0x4 @ offset 0x0
Copied 2097152 bytes from address 0x00000000 in flash to spi_read
+ sha256sum spi_read spi_test
4bda3a28f4ffe603c0ec1258c0034d65a1a0d35ab7bd523a834608adabf03cc5 spi_read
51acf03d440fea3017e99b0dfd9711173044c57be0e2699221e969b6c02a2133 spi_test
+ mtd_debug info /dev/mtd0
mtd.type = MTD_NORFLASH
mtd.flags = MTD_CAP_NANDFLASH
mtd.size = 33554432 (32M)
mtd.erasesize = 65536 (64K)
mtd.writesize = 16
mtd.oobsize = 0
regions = 0
+ alias 'show_sectors=grep -A4 "locked sectors" /sys/kernel/debug/spi-nor/spi0.0/params'
+ flash_lock -u /dev/mtd0
+ flash_lock -i /dev/mtd0
Device: /dev/mtd0
Start: 0
Len: 0x2000000
Lock status: unlocked
Return code: 0
+ mtd_debug erase /dev/mtd0 0 2097152
Erased 2097152 bytes from address 0x00000000 in flash
+ mtd_debug write /dev/mtd0 0 2097152 spi_test
Copied 2097152 bytes from spi_test to address 0x00000000 in flash
+ mtd_debug read /dev/mtd0 0 2097152 spi_read
[ 22.062778] spi_nor_read [1882] [ret: 0] SR3 0x4 @ offset 0x0
Copied 2097152 bytes from address 0x00000000 in flash to spi_read
+ sha256sum spi_read spi_test
51acf03d440fea3017e99b0dfd9711173044c57be0e2699221e969b6c02a2133 spi_read
51acf03d440fea3017e99b0dfd9711173044c57be0e2699221e969b6c02a2133 spi_test
+ grep -A4 'locked sectors' /sys/kernel/debug/spi-nor/spi0.0/params
locked sectors
region (in hex) | status | #sectors
------------------+----------+---------
00000000-01ffffff | unlocked | 512
+ flash_lock -l /dev/mtd0
+ flash_lock -i /dev/mtd0
Device: /dev/mtd0
Start: 0
Len: 0x2000000
Lock status: locked
Return code: 1
+ mtd_debug erase /dev/mtd0 0 2097152
Erased 2097152 bytes from address 0x00000000 in flash
+ mtd_debug read /dev/mtd0 0 2097152 spi_read
[ 23.733210] spi_nor_read [1882] [ret: 0] SR3 0x4 @ offset 0x0
Copied 2097152 bytes from address 0x00000000 in flash to spi_read
+ sha256sum spi_read spi_test
51acf03d440fea3017e99b0dfd9711173044c57be0e2699221e969b6c02a2133 spi_read
51acf03d440fea3017e99b0dfd9711173044c57be0e2699221e969b6c02a2133 spi_test
+ dd 'if=/dev/urandom' 'of=./spi_test2' 'bs=1M' 'count=2'
2+0 records in
2+0 records out
+ mtd_debug write /dev/mtd0 0 2097152 spi_test2
Copied 2097152 bytes from spi_test2 to address 0x00000000 in flash
+ mtd_debug read /dev/mtd0 0 2097152 spi_read2
[ 26.172756] spi_nor_read [1882] [ret: 0] SR3 0x4 @ offset 0x0
Copied 2097152 bytes from address 0x00000000 in flash to spi_read2
+ sha256sum spi_read spi_read2 spi_test spi_test2
51acf03d440fea3017e99b0dfd9711173044c57be0e2699221e969b6c02a2133 spi_read
51acf03d440fea3017e99b0dfd9711173044c57be0e2699221e969b6c02a2133 spi_read2
51acf03d440fea3017e99b0dfd9711173044c57be0e2699221e969b6c02a2133 spi_test
c17d6a0ddfc0f437e7729e42b91b5bd776f2eff4634a7f55c2e88e0774e43ab7 spi_test2
+ grep -A4 'locked sectors' /sys/kernel/debug/spi-nor/spi0.0/params
locked sectors
region (in hex) | status | #sectors
------------------+----------+---------
00000000-01ffffff | locked | 512
+ flash_lock -u /dev/mtd0
+ cat /sys/class/mtd/mtd0/size
+ size=33554432
+ cat /sys/class/mtd/mtd0/erasesize
+ bs=65536
+ grep unlocked /sys/kernel/debug/spi-nor/spi0.0/params
+ sed -e 's/.*unlocked | //'
+ nsectors=512
+ ss=65536
+ bps=1
+ flash_lock -u /dev/mtd0
+ flash_lock -l /dev/mtd0 33423360 2
+ grep -A4 'locked sectors' /sys/kernel/debug/spi-nor/spi0.0/params
locked sectors
region (in hex) | status | #sectors
------------------+----------+---------
00000000-01fdffff | unlocked | 510
01fe0000-01ffffff | locked | 2
+ flash_lock -u /dev/mtd0 33423360 1
+ grep -A4 'locked sectors' /sys/kernel/debug/spi-nor/spi0.0/params
locked sectors
region (in hex) | status | #sectors
------------------+----------+---------
00000000-01feffff | unlocked | 511
01ff0000-01ffffff | locked | 1
+ flash_lock -u /dev/mtd0
+ flash_lock -l /dev/mtd0 25165824 128
+ grep -A4 'locked sectors' /sys/kernel/debug/spi-nor/spi0.0/params
locked sectors
region (in hex) | status | #sectors
------------------+----------+---------
00000000-017fffff | unlocked | 384
01800000-01ffffff | locked | 128
+ flash_lock -u /dev/mtd0
+ flash_lock -l /dev/mtd0 0 2
+ grep -A4 'locked sectors' /sys/kernel/debug/spi-nor/spi0.0/params
locked sectors
region (in hex) | status | #sectors
------------------+----------+---------
00000000-0001ffff | locked | 2
00020000-01ffffff | unlocked | 510
+ flash_lock -u /dev/mtd0 65536 1
+ grep -A4 'locked sectors' /sys/kernel/debug/spi-nor/spi0.0/params
locked sectors
region (in hex) | status | #sectors
------------------+----------+---------
00000000-0000ffff | locked | 1
00010000-01ffffff | unlocked | 511
+ all_but_one=511
+ flash_lock -u /dev/mtd0
+ flash_lock -l /dev/mtd0 65536 511
+ grep -A4 'locked sectors' /sys/kernel/debug/spi-nor/spi0.0/params
locked sectors
region (in hex) | status | #sectors
------------------+----------+---------
00000000-0000ffff | unlocked | 1
00010000-01ffffff | locked | 511
+ flash_lock -u /dev/mtd0 65536 1
+ grep -A4 'locked sectors' /sys/kernel/debug/spi-nor/spi0.0/params
locked sectors
region (in hex) | status | #sectors
------------------+----------+---------
00000000-0001ffff | unlocked | 2
00020000-01ffffff | locked | 510
+ flash_lock -u /dev/mtd0
+ flash_lock -l /dev/mtd0 0 511
+ grep -A4 'locked sectors' /sys/kernel/debug/spi-nor/spi0.0/params
locked sectors
region (in hex) | status | #sectors
------------------+----------+---------
00000000-01feffff | locked | 511
01ff0000-01ffffff | unlocked | 1
+ flash_lock -u /dev/mtd0 33423360 1
+ grep -A4 'locked sectors' /sys/kernel/debug/spi-nor/spi0.0/params
locked sectors
region (in hex) | status | #sectors
------------------+----------+---------
00000000-01fdffff | locked | 510
01fe0000-01ffffff | unlocked | 2
---
drivers/mtd/spi-nor/winbond.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/mtd/spi-nor/winbond.c b/drivers/mtd/spi-nor/winbond.c
index ec3309ead1c6..f2daab39ea57 100644
--- a/drivers/mtd/spi-nor/winbond.c
+++ b/drivers/mtd/spi-nor/winbond.c
@@ -489,7 +489,7 @@ static const struct flash_info winbond_nor_parts[] = {
.flags = SPI_NOR_QUAD_PP | SPI_NOR_HAS_LOCK | SPI_NOR_HAS_TB | SPI_NOR_HAS_CMP,
.no_sfdp_flags = SECT_4K | SPI_NOR_DUAL_READ | SPI_NOR_QUAD_READ,
}, {
- /* W25Q256JW-M */
+ /* W25Q256JW-M, W25Q25PW-M */
.id = SNOR_ID(0xef, 0x80, 0x19),
.name = "w25q256jwm",
.size = SZ_32M,
--
2.54.0