[PATCH v5 0/12] cpufreq: Add support for Exynos 5800, 5420, and 5422

Viresh Kumar viresh.kumar at linaro.org
Thu Dec 3 02:37:03 PST 2015

On 03-12-15, 11:26, Ben Gamari wrote:
> Viresh Kumar <viresh.kumar at linaro.org> writes:
> > But, before I start reviewing this series, I have few comments.
> > - We weren't able to use cpufreq-dt driver for big LITTLE platforms
> >   earlier, as it never had multi cluster support and we wanted
> >   clock-sharing information via DT.
> Fair enough.
> > - That is all fixed now.
> I did not see any mention of this in the cpufreq-dt driver binding
> documentation, otherwise I would have tried going this route.
> Do you have any references? I'd be happy to examine what would be
> necessary to go this route although, being an independent contributor,
> it may take time.

You wouldn't find in cpufreq-dt documentation as its not specific to
that. I have seen you DT patches now, and you have created the OPP
tables mostly correctly. Just create the cpufreq-platform device for
cpufreq-dt instead of arm-big-little one. And it should just work.

> > - I want Samsung's big LITTLE platforms to use cpufreq-dt and drop
> >   arm_big_little driver completely.
> That sounds like a great direction going forward. However, I would still
> kindly request that you consider this series.
> The existence of future plans of course does not change the fact that
> users have real hardware today; hardware that they have spent money on
> and would like to use. Cpufreq support has already been deferred once
> for similar reasons of interface churn which essentially forestalled
> working functionality from entering the kernel by eight months; I'd
> really like to avoid having this happen again.

I am not talking about any future plans here that need some work to be
done. Its all working today, you just need to use a different driver.

> Sounds reasonable to me. However, I'd just like to reiterate that this
> line of work can be pursued independently from the upstreaming of this
> series.

I think this is the right time to upstream the right solution. Just
try it once, if you face lots of difficulties or issues, then we can
ofcourse see..

NOTE: Check how OPP nodes are required to be created now in
linux-next. They should be named like opp@<freq-hz>. Something I
noticed in your DTs.


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