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

Viresh Kumar viresh.kumar at linaro.org
Wed Jun 22 03:37:52 PDT 2016


On 22-06-16, 12:36, Krzysztof Kozlowski wrote:
> On Wed, Jun 22, 2016 at 11:53 AM, Arnd Bergmann <arnd at arndb.de> wrote:
> > 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.
> 
> I think that would be actually different patch, not endian related.
> The concurrent operations here are excluded by mutexes so this looks
> safe.
> 
> Viresh,
> I saw your ack. Do you prefer me to take the set through samsung-soc?

Sure.

-- 
viresh



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