Re: [PATCH V8 3/3] OPP: Allow "opp-hz" and "opp-microvolt" to contain magic values

From: Viresh Kumar
Date: Wed Dec 27 2017 - 03:56:54 EST


On 26-12-17, 14:29, Rob Herring wrote:
> On Mon, Dec 18, 2017 at 03:51:30PM +0530, Viresh Kumar wrote:

> > +On some platforms the exact frequency or voltage may be hidden from the OS by
> > +the firmware and the "opp-hz" or the "opp-microvolt" properties may contain
> > +magic values that represent the frequency or voltage in a firmware dependent
> > +way, for example an index of an array in the firmware.
>
> I'm still not convinced this is a good idea.

You were kind-of a few days back :)

lkml.kernel.org/r/CAL_JsqK-qtAaM_Ou5NtxcWR3F_q=8rMPJUm-VqGtKhbtWe5SAQ@xxxxxxxxxxxxxx

So here is the deal:

- I proposed "domain-performance-state" property for this stuff
initially.
- But Kevin didn't like that and proposed reusing "opp-hz" and
"opp-microvolt", which we all agreed to multiple times..
- And we are back to the same discussion now and its painful and time
killing for all of us.

TBH, I don't have too strong preferences about any of the suggestions
you guys have and I need you guys to tell me what binding changes to
do here and I will do that.

> If you have firmware
> partially managing things, then I think we should have platform specific
> bindings or drivers.

What about the initial idea then, like "performance-state" for the
power domains ? All platforms will anyway replicate that binding only.

> This is complex enough I'm not taking silence from Stephen as an okay.

Sure, but I am not sure how to make him speak :)

--
viresh