[PATCH 1/2] cpufreq: exynos: use relaxed IO accesors

Arnd Bergmann arnd at arndb.de
Wed Jun 22 02:53:32 PDT 2016


On Wednesday, June 22, 2016 10:33:03 AM CEST Ben Dooks wrote:
> The use of __raw IO accesors is not endian safe and should be used
> sparingly. The relaxed variants should be as lightweight and also
> are endian safe.
> 
> Signed-off-by: Ben Dooks <ben.dooks at codethink.co.uk>
> 

Why not use the normal readl/writel() here instead of the relaxed version?

Either one should work here, but in general I'd recommend using the
non-relaxed version unless code is particularly performance sensitive.

The main argument for that is to not let people get used to using
_relaxed() all the time because it causes some very hard to debug
problems in the cases where you actually need the barriers.

	Arnd




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