Re: [PATCH v8 0/7] Enhanced autonomous selection and improvements

[Rafael J. Wysocki]

On Thu, Feb 26, 2026 at 2:59 PM Sumit Gupta <sumitg@xxxxxxxxxx> wrote:
>
>
> > This patch series improves the CPPC cpufreq driver with new ACPI APIs
> > and enhancements for Autonomous Selection (auto_select).
> >
> > CPPC auto_select enables hardware-driven CPU performance scaling using
> > Energy Performance Preference (EPP) hints. Currently, there's limited
> > runtime control and visibility into CPPC performance registers.
> >
> > The series adds cppc_get_perf() API to read performance controls, updates
> > MIN_PERF/MAX_PERF in target callbacks using existing scaling_min/max_freq
> > interface similar to intel_cpufreq HWP handling, and exposes perf_limited
> > register via sysfs to detect throttling events.
> >
> > The patches are grouped as below:
> > - Patch 1: Add cppc_get_perf() API (independent).
> > - Patch 2: Warn on missing mandatory DESIRED_PERF (independent).
> > - Patch 3: Extend cppc_set_epp_perf for FFH/SystemMemory (independent).
> > - Patch 4: Update cached perf_ctrls on sysfs write (independent).
> > - Patch 5: Update MIN_PERF/MAX_PERF in target callbacks (depends on 4).
> > - Patch 6-7: APIs, sysfs and doc for perf_limited (independent).
>
> Gentle ping.
>
> If there are no further comments, could this be considered for merging.

Applied as 7.1 material, thanks!

That said, wouldn't it be prudent to check cpc_read() return values everywhere?

They are handled quite inconsistently and this series doesn't improve that.