[PATCH v4] mtd: spi-nor: Add support for sst26vf032b flash

[Miquel Raynal]

Describe this new part. The datasheet is public.

Link: https://ww1.microchip.com/downloads/aemDocuments/documents/MPD/ProductDocuments/DataSheets/SST26VF032B-SST26VF032BA-2.5V-3.0V-32-Mbit-Serial-Quad-IO-%28SQI%29-Flash-Memory-20005218K.pdf

Here are the sfdp tables plus base testing to show it works.

$ cat /sys/bus/spi/devices/spi0.0/spi-nor/partname
sst26vf032b
$ cat /sys/bus/spi/devices/spi0.0/spi-nor/jedec_id
bf2642
$ cat /sys/bus/spi/devices/spi0.0/spi-nor/manufacturer
sst
$ xxd -p /sys/bus/spi/devices/spi0.0/spi-nor/sfdp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$ md5sum /sys/bus/spi/devices/spi0.0/spi-nor/sfdp
e7efddddb3d5ee89ca37bf6b6e789645  /sys/bus/spi/devices/spi0.0/spi-nor/sfdp

$ dd if=/dev/urandom of=./qspi_test bs=1M count=1
1+0 records in
1+0 records out
$ mtd_debug write /dev/mtd0 0 1048576 qspi_test
Copied 1048576 bytes from qspi_test to address 0x00000000 in flash
$ mtd_debug erase /dev/mtd0 0 1048576
Erased 1048576 bytes from address 0x00000000 in flash
$ mtd_debug read /dev/mtd0 0 1048576 qspi_read
Copied 1048576 bytes from address 0x00000000 in flash to qspi_read
$ hexdump qspi_read
0000000 ffff ffff ffff ffff ffff ffff ffff ffff
*
0100000
$ mtd_debug write /dev/mtd0 0 1048576 qspi_test
Copied 1048576 bytes from qspi_test to address 0x00000000 in flash
$ mtd_debug read /dev/mtd0 0 1048576 qspi_read
Copied 1048576 bytes from address 0x00000000 in flash to qspi_read
$ sha1sum qspi_test qspi_read
2f2f191c7a937eca5db21a1c39e79e7327587cc1  qspi_test
2f2f191c7a937eca5db21a1c39e79e7327587cc1  qspi_read

Signed-off-by: Miquel Raynal <miquel.raynal at bootlin.com>
---

Changes in v4:
* Just providing the PARSE_SFDP flag seem to work but actually does
  not. As opposed to the NAND world which loudly fails when WP is
  enabled, here the destructive operations are silently ignored by the
  chip, so actually the reads work but without the additional
  LOCK/SWP_IS_VOLATILE flags, the chip does not process writes and
  erasures. Reinstate these two lines as in my backported patch (a
  linux4microchip kernel on which I actually run this hardware), so I am
  sure it also works in mainline.

Changes in v3:
* Dropped the second patch (untested changes as advised by Tudor).  
* Avoided playing with locking as I cannot test it either: simplified
  the diff by just using the PARSE_SFDP flag.
* Rebased on top of -rc1 and adapted the patch to the current state.

 drivers/mtd/spi-nor/sst.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/mtd/spi-nor/sst.c b/drivers/mtd/spi-nor/sst.c
index 688eb20c763e..414ee4692fd1 100644
--- a/drivers/mtd/spi-nor/sst.c
+++ b/drivers/mtd/spi-nor/sst.c
@@ -111,6 +111,10 @@ static const struct flash_info sst_nor_parts[] = {
 			      SPI_NOR_QUAD_READ) },
 	{ "sst26vf016b", INFO(0xbf2641, 0, 64 * 1024, 32)
 		NO_SFDP_FLAGS(SECT_4K | SPI_NOR_DUAL_READ) },
+	{ "sst26vf032b", INFO(0xbf2642, 0, 0, 0)
+		FLAGS(SPI_NOR_HAS_LOCK | SPI_NOR_SWP_IS_VOLATILE)
+		PARSE_SFDP
+		.fixups = &sst26vf_nor_fixups },
 	{ "sst26vf064b", INFO(0xbf2643, 0, 64 * 1024, 128)
 		FLAGS(SPI_NOR_HAS_LOCK | SPI_NOR_SWP_IS_VOLATILE)
 		NO_SFDP_FLAGS(SECT_4K | SPI_NOR_DUAL_READ | SPI_NOR_QUAD_READ)
-- 
2.34.1