On 10/03/2023 00:59, Ashutosh Dixit wrote:
The fallback to requested freq does not work for SLPC because SLPC does not use 'struct intel_rps'. Also for SLPC requested freq can only be obtained from a hw register after acquiring forcewake which we don't want to do for PMU. Therefore remove fallback to requested freq for SLPC. The actual freq will be 0 when gt is in RC6 which is correct. Also this is rare since PMU freq sampling happens only when gt is unparked. Signed-off-by: Ashutosh Dixit <ashutosh.dixit@xxxxxxxxx> --- drivers/gpu/drm/i915/i915_pmu.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/i915_pmu.c b/drivers/gpu/drm/i915/i915_pmu.c index 7ece883a7d95..f697fabed64a 100644 --- a/drivers/gpu/drm/i915/i915_pmu.c +++ b/drivers/gpu/drm/i915/i915_pmu.c @@ -393,7 +393,14 @@ frequency_sample(struct intel_gt *gt, unsigned int period_ns) * frequency. Fortunately, the read should rarely fail! */ val = intel_rps_read_actual_frequency_fw(rps); - if (!val) + + /* + * SLPC does not use 'struct intel_rps'. Also for SLPC + * requested freq can only be obtained after acquiring + * forcewake and reading a hw register. For SLPC just + * let val be 0 + */ + if (!val && !intel_uc_uses_guc_slpc(>->uc)) val = intel_gpu_freq(rps, rps->cur_freq);
I really dislike sprinkling of "uses slpc" since I think the thing hasn't really been integrated nicely. Case in point is probably the flow duality in intel_rps_boost. Data structures as well, even though some fields and concepts are shared.
For instance why we can't have the notion of software tracked cur_freq in rps, and/or have it zero if with SLPC we can't have it otherwise?
I will abstain, sorry. Regards, Tvrtko
add_sample_mult(&pmu->sample[__I915_SAMPLE_FREQ_ACT],
