[PATCH v2] drm/xe: GPU frequency tracing support

[Dixit, Ashutosh]

On Tue, 19 Aug 2025 21:25:43 -0700, Sebinraj, S wrote:
>
> We went for this addition rather than the one in xe_pmu (via perf stat - user space tool),
> as we have a requirement to have the trace point available at d/evens/power/gpu_frequency for Android xTS.
> In this case the user won't be triggering the perf subsystem for gpu frequency for gt0, gt1.. even if we add the trace points in xe_pmu.

Why not? Which userspace tool is consuming this ftrace and they can't
enable the PMU event?

The way the ftrace event is implemented here, it really doesn't provide any
more information than what is provided by the PMU. IMO, a ftrace might be
more acceptable if the freq change event emanated from GuC itself where the
freq change is actually implemented. That would need a change to GuC FW, so
maybe not an option at present.

Also, similar to Rodrigo's comment on the work period series, if we need
d/events/power/gpu_frequency (rather than d/events/power/xe_gpu_frequency),
that should be added at the drm level rather than at xe level? Would that
be acceptable?

Thanks.
--
Ashutosh