Commit Graph

3 Commits

Author SHA1 Message Date
Michael Walle
b9ee2a910d mtd: spi-nor: atmel: fix unlock_all() for AT25FS010/040
[ Upstream commit 8c174d1511d235ed6c049dcb2b704777ad0df7a5 ]

These flashes have some weird BP bits mapping which aren't supported in
the current locking code. Just add a simple unlock op to unprotect the
entire flash array which is needed for legacy behavior.

Fixes: 3e0930f109 ("mtd: spi-nor: Rework the disabling of block write protection")
Signed-off-by: Michael Walle <michael@walle.cc>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Reviewed-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Link: https://lore.kernel.org/r/20201203162959.29589-7-michael@walle.cc
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-30 11:53:41 +01:00
Michael Walle
d4f620ed49 mtd: spi-nor: atmel: remove global protection flag
[ Upstream commit e6204d4620276398ed7317d64c369813a1f96615 ]

This is considered bad for the following reasons:
 (1) We only support the block protection with BPn bits for write
     protection. Not all Atmel parts support this.
 (2) Newly added flash chip will automatically inherit the "has
     locking" support and thus needs to explicitly tested. Better
     be opt-in instead of opt-out.
 (3) There are already supported flashes which doesn't support
     the locking scheme. So I assume this wasn't properly tested
     before adding that chip; which enforces my previous argument
     that locking support should be an opt-in.

Remove the global flag and add individual flags to all flashes which
supports BP locking. In particular the following flashes don't support
the BP scheme:
 - AT26F004
 - AT25SL321
 - AT45DB081D

Please note, that some flashes which are marked as SPI_NOR_HAS_LOCK just
support Global Protection, i.e. not our supported block protection
locking scheme. This is to keep backwards compatibility with the
current "unlock all at boot" mechanism. In particular the following
flashes doesn't have BP bits:
 - AT25DF041A
 - AT25DF321
 - AT25DF321A
 - AT25DF641
 - AT26DF081A
 - AT26DF161A
 - AT26DF321

Signed-off-by: Michael Walle <michael@walle.cc>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Reviewed-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Link: https://lore.kernel.org/r/20201203162959.29589-4-michael@walle.cc
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-30 11:53:41 +01:00
Boris Brezillon
f7242bfc02 mtd: spi-nor: Move Atmel bits out of core.c
Create a SPI NOR manufacturer driver for Atmel chips, and move the
Atmel definitions outside of core.c.

Signed-off-by: Boris Brezillon <bbrezillon@kernel.org>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
2020-03-17 09:28:02 +02:00