[PATCH V7 2/3] OPP: Allow multiple OPP tables to be passed via DT

Viresh Kumar viresh.kumar at linaro.org
Wed Jun 17 06:33:14 PDT 2015

On 17-06-15, 08:23, Rob Herring wrote:
> > +                       operating-points-v2 = <&cpu0_opp_table_slow>, <&cpu0_opp_table_fast>;
> You've made a fundamental change here in that this can now be a list
> of phandles. There should be some description on what a list means
> (merge the tables?, select one?).

Did you miss the description I wrote few lines earlier or are you
asking for something else? This is what I wrote earlier:

> > +Devices may want to choose OPP tables at runtime and so can provide a list of
> > +phandles here. But only *one* of them should be chosen at runtime.

So, clearly only ONE of the tables should be used.

> I think this needs to have a defined order and the platform should
> know what that is. For example, if you read the efuses and decide you
> need the "slow" table, you know to pick the first entry. Then you
> don't need opp-name. Does that work for QCom?

Why forcing on the order here? For example, consider a case where the
platform can have four tables, A B C D. Now DT is free to pass all
four or just a subset of those. Like, for some boards table B doesn't
stand valid. And so it may wanna pass just A C D. And so keeping these
tables in order is going to break for sure. Flexibility is probably
better in this case.


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