Re: [PATCH v3 01/17] asm-generic: io: implement relaxed accessor macros as conditional wrappers

From: Arnd Bergmann
Date: Thu Sep 25 2014 - 06:33:15 EST

On Wednesday 24 September 2014 18:17:20 Will Deacon wrote:
> {read,write}{b,w,l,q}_relaxed are implemented by some architectures in
> order to permit memory-mapped I/O accesses with weaker barrier semantics
> than the non-relaxed variants.
> This patch adds wrappers to asm-generic so that drivers can rely on the
> relaxed accessors being available, even if they don't always provide
> weaker ordering guarantees. Since some architectures both include
> asm-generic/io.h and define some relaxed accessors, the definitions here
> are conditional for the time being.
> Cc: Arnd Bergmann <arnd@xxxxxxxx>
> Signed-off-by: Will Deacon <will.deacon@xxxxxxx>
> ---
> include/asm-generic/io.h | 26 ++++++++++++++++++++++++++
> 1 file changed, 26 insertions(+)

Acked-by: Arnd Bergmann <arnd@xxxxxxxx>
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