linux/include
Stefan Roese 1648eaaa15 mtd: cfi_cmdset_0002: Support Persistent Protection Bits (PPB) locking
Currently cfi_cmdset_0002.c does not support PPB locking of sectors. This
patch adds support for this locking/unlocking mechanism. It is needed on
some platforms, since newer U-Boot versions do support this PPB locking
and protect for example their environment sector(s) this way.

This PPB locking/unlocking will be enabled for all devices supported by
cfi_cmdset_0002 reporting 8 in the CFI word 0x49 (Sector Protect/Unprotect
scheme).

Please note that PPB locking does support sector-by-sector locking. But
the whole chip can only be unlocked together. So unlocking one sector
will automatically unlock all sectors of this device. Because of this
chip limitation, the PPB unlocking function saves the current locking
status of all sectors before unlocking the whole device. After unlocking
the saved locking status is re-configured. This way only the addressed
sectors will be unlocked.

To selectively enable this advanced sector protection mechanism, the
device-tree property "use-advanced-sector-protection" has been created.
To enable support for this locking this property needs to be present in the
flash DT node. E.g.:

nor_flash@0,0 {
	compatible = "amd,s29gl256n", "cfi-flash";
	bank-width = <2>;
	use-advanced-sector-protection;
	...

Tested with Spansion S29GL512S10THI and Micron JS28F512M29EWx flash
devices.

Signed-off-by: Stefan Roese <sr@denx.de>
Tested-by: Holger Brunck <holger.brunck@keymile.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
2013-02-04 09:27:33 +02:00
..
acpi
asm-generic Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k 2013-01-23 13:31:15 -08:00
clocksource
crypto
drm Merge branch 'drm-intel-fixes' of git://people.freedesktop.org/~danvet/drm-intel 2013-01-11 07:52:48 +10:00
keys
linux mtd: cfi_cmdset_0002: Support Persistent Protection Bits (PPB) locking 2013-02-04 09:27:33 +02:00
math-emu
media
memory
misc
net ipv4: Add a socket release callback for datagram sockets 2013-01-21 14:17:05 -05:00
pcmcia
ras
rdma UAPI: Remove empty Kbuild files 2013-01-02 17:36:10 -08:00
rxrpc
scsi
sound Merge remote-tracking branch 'asoc/fix/cs4271' into tmp 2013-01-10 12:22:11 +00:00
target target: Introduce TCM_NO_SENSE 2013-01-10 20:06:08 -08:00
trace Various bug fixes for ext4. Perhaps the most serious bug fixed is one 2013-01-02 09:57:34 -08:00
uapi TTY/serial fixes for 3.8-rc4 2013-01-18 14:05:59 -08:00
video
xen Bugfixes: 2012-12-18 12:26:54 -08:00
Kbuild UAPI: Remove empty Kbuild files 2013-01-02 17:36:10 -08:00