If we park/unpark faster than we can respond to RPS events, we never will process a downlock event after expiring a waitboost, and thus we will forever restart the GPU at max clocks even if the workload switches and doesn't justify full power. Closes: https://gitlab.freedesktop.org/drm/intel/issues/1500 Fixes: 3e7abf814193 ("drm/i915: Extract GT render power state management") Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> Cc: Andi Shyti <andi.shyti@xxxxxxxxx> Cc: Lyude Paul <lyude@xxxxxxxxxx> --- drivers/gpu/drm/i915/gt/intel_rps.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/drivers/gpu/drm/i915/gt/intel_rps.c b/drivers/gpu/drm/i915/gt/intel_rps.c index 7bf631ca560b..50884aeac49c 100644 --- a/drivers/gpu/drm/i915/gt/intel_rps.c +++ b/drivers/gpu/drm/i915/gt/intel_rps.c @@ -771,6 +771,19 @@ void intel_rps_park(struct intel_rps *rps) intel_uncore_forcewake_get(rps_to_uncore(rps), FORCEWAKE_MEDIA); rps_set(rps, rps->idle_freq, false); intel_uncore_forcewake_put(rps_to_uncore(rps), FORCEWAKE_MEDIA); + + /* + * Since we will try and restart from the previously requested + * frequency on unparking, treat this idle point as a downlock + * interrupt and reduce the frequency for resume. If we park/unpark + * more frequently than the rps worker can run, we will not respond + * to any EI and never see a change in frequency. + * + * (Note the we accommodate Cherryview's limitation of only using + * an even bin by applying it to all.) + */ + rps->cur_freq = + max_t(u8, round_down(rps->cur_freq - 1, 2), rps->min_freq); } void intel_rps_boost(struct i915_request *rq) -- 2.20.1 _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
