Re: [RFC V7 2/2] OPP: Allow "opp-hz" and "opp-microvolt" to contain magic values

From: Viresh Kumar
Date: Tue Oct 31 2017 - 22:18:05 EST


On 31 October 2017 at 16:02, Rob Herring <robh+dt@xxxxxxxxxx> wrote:
> Why not a new property for magic values? opp-magic? Don't we want to
> know when we have magic values?

I have kept a separate property since beginning (domain-performance-state)
and moved to using these magic values in the existing field because of the
suggestion Kevin gave earlier.

https://marc.info/?l=linux-kernel&m=149306082218001&w=2

I am not sure what to do now :)

> Wouldn't magic values in opp-hz get propagated to user space?

The OPP core puts them in debugfs just to know how the OPPs are
set. Otherwise, I am not sure that the power domain core/drivers would
be exposing that to user space.

> I can
> see the complaints now. "My 4GHz processor is running at 6Hz!" Just
> like people complain when BogoMIPS is not high enough.

Hmm, would adding the right user type in bindings would be good enough
for that? I mean, we can clearly add that only power-domains that are
managed by firmware are allowed to use magic values here. But not sure
if we should put such stuff in bindings.

--
viresh