pstore-ram: Allow optional mapping with pgprot_noncached

On some ARMs the memory can be mapped pgprot_noncached() and still
be working for atomic operations. As pointed out by Colin Cross
<[email protected]>, in some cases you do want to use
pgprot_noncached() if the SoC supports it to see a debug printk
just before a write hanging the system.

On ARMs, the atomic operations on strongly ordered memory are
implementation defined. So let's provide an optional kernel parameter
for configuring pgprot_noncached(), and use pgprot_writecombine() by
default.

Cc: Arnd Bergmann <[email protected]>
Cc: Rob Herring <[email protected]>
Cc: Randy Dunlap <[email protected]>
Cc: Anton Vorontsov <[email protected]>
Cc: Colin Cross <[email protected]>
Cc: Olof Johansson <[email protected]>
Cc: Russell King <[email protected]>
Cc: [email protected]
Acked-by: Kees Cook <[email protected]>
Signed-off-by: Tony Lindgren <[email protected]>
Signed-off-by: Tony Luck <[email protected]>

0 files changed, 0 insertions, 0 deletions