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

Viresh Kumar viresh.kumar at linaro.org
Wed Jun 17 19:25:43 PDT 2015

On 17-06-15, 18:30, Stephen Boyd wrote:
> An operating-point(s?)-names property seems ok... but doesn't that mean
> that every CPU that uses the OPP has to have the same list of
> operating-point-names?

Why do you think so? For me the operating-points-v2-names property
will be present in CPU node (as there is no OPP node which can have
it) and so every CPU is free to choose what it wants to.

> It would make sense to me if the operating points
> were called something different depending on *which* CPU is using them,
> but in this case the only name for the operating point is "slow" or
> "fast", etc.

I am completely confused now. :)

The problem you stated now was there with the current state of
bindings. The name is embedded into the OPP table node and so is fixed
for all the CPUs. Moving it to the CPU node will give all CPUs a
chance to name it whatever they want to. And the same list has to be
replicated to all CPUs sharing the clock rails.

> In reality we've assigned them names like speedX-binY-vZ so that we know
> which speed bin, voltage bin, and version they're part of. Maybe OPP
> node properties like qcom,speed-bin = <u32>, qcom,pvs-bin = <u32>, etc.
> would be better?

Lets see, only if we can't get the generic stuff for this.

> At the least, operating-points-names will be required on qcom platforms.
> A fixed ordering known to the platform would mean that we know exactly
> how many voltage bins and speed bins and how many voltage bins per speed
> bin are used for a particular SoC, which we've avoided knowing so far.

What are we referring to fixed ordering? If we have both a list of
phandles to OPP tables and a list of names, they can be rearranged in
whatever fashion we want. Isn't it?


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