Re: [PATCH v3 3/3] [RFC] CPUFreq: Add support for cpu-perf-dependencies

[Viresh Kumar]

On 02-11-20, 12:01, Nicola Mazzucato wrote:
> Hi All,
> 
> This is a continuation of the previous v2, where we focused mostly on the
> dt binding.
> 
> I am seeking some feedback/comments on the following two approaches.
> 
> Intro:
> We have seen that in a system where performance control and hardware
> description do not match (i.e. per-cpu), we still need the information of
> how the v/f lines are shared among the cpus. We call this information
> "performance dependencies".
> We got this info through the opp-shared (the previous 2 patches aim for
> that).
> 
> Problem:
> How do we share such info (retrieved from a cpufreq driver) to other
> consumers that rely on it? I have two proposals.

FWIW, we already have a case in kernel where something similar is
done.

commit f4fd3797848a ("acpi-cpufreq: Add new sysfs attribute freqdomain_cpus")

and the information is shared via:

/sys/devices/system/cpu/cpu#/cpufreq/freqdomain_cpus

-- 
viresh