Re: [PATCH v2 1/3] cpufreq: add resolve_freq driver callback

From: Viresh Kumar
Date: Tue May 31 2016 - 01:30:31 EST

On 30-05-16, 08:31, Steve Muckle wrote:
> My goal here was to have the system operate in this case in a manner
> that is obviously not optimized (running at fmax), so the platform owner
> realizes that the cpufreq driver doesn't fully support the schedutil
> governor.
> I was originally going to just return an error code but that also means
> having to check for it which would be nice to avoid if possible on this
> fast path.

Okay, I get what you are saying.

But all we are doing here is to make things fast by not sending IPIs,
etc. That should *not* lead to a behavior where the frequency stays at
MAX all the time even if the driver doesn't provide this callback or
the freq-table.

If we just return the target_freq in this case instead of UINT_MAX,
the platform may eventually have some unnecessary IPIs, wakeups, etc,
but its frequency will still be switched properly.

Wouldn't that be a better choice ?