[PATCH] Offer 'uncacheable memory' as DMA coherent memory for ARMv6

[Catalin Marinas]

On Wed, 2010-01-13 at 18:03 +0000, Russell King - ARM Linux wrote:
> ARMv7 uses 'uncacheable normal memory' to implement DMA coherent memory,
> since mapping the same memory as two different types is defined to be
> unpredictable.
> 
> The same is strictly true for ARMv6 as well, although no bad behaviour
> has been observed thus far.  However, we do want to move ARMv6 to be
> architecturally compliant.  The down side is that some drivers may only
> have been tested on ARMv6, and may be missing the necessary barriers to
> make them work.
> 
> So, offer this as a configuration option, defaulting to enabled (to
> encourage drivers to be fixed.)
> 
> Signed-off-by: Russell King <rmk+kernel at arm.linux.org.uk>

Looks ok to me.

Reviewed-by: Catalin Marinas <catalin.marinas at arm.com>

-- 
Catalin