drm/i915/gt: Sanitize RPS interrupts upon resume

Currently we clear and disable the RPS pm interrupts on module load, and
presume that they remain disabled forevermore. However, the mask is
cleared on suspend and so after resume they may start showing up again
unexepectedly.

Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/1811
Fixes: 8e99299a ("drm/i915/gt: Track use of RPS interrupts in flags")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Andi Shyti <andi@etezian.org>
Reviewed-by: Andi Shyti <andi@etezian.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200502173512.32353-1-chris@chris-wilson.co.uk

drivers/gpu/drm/i915/gt/intel_gt_pm.c

@@ -171,6 +171,8 @@ static void gt_sanitize(struct intel_gt *gt, bool force)
 		if (engine->reset.finish)
 			engine->reset.finish(engine);
 
+	intel_rps_sanitize(&gt->rps);
+
 	intel_uncore_forcewake_put(gt->uncore, FORCEWAKE_ALL);
 	intel_runtime_pm_put(gt->uncore->rpm, wakeref);
 }

drivers/gpu/drm/i915/gt/intel_rps.c

@@ -1844,8 +1844,11 @@ void intel_rps_init(struct intel_rps *rps)
 
 	if (INTEL_GEN(i915) >= 8 && INTEL_GEN(i915) < 11)
 		rps->pm_intrmsk_mbz |= GEN8_PMINTR_DISABLE_REDIRECT_TO_GUC;
+}
 
-	if (INTEL_GEN(i915) >= 6)
+void intel_rps_sanitize(struct intel_rps *rps)
+{
+	if (INTEL_GEN(rps_to_i915(rps)) >= 6)
 		rps_disable_interrupts(rps);
 }
 

drivers/gpu/drm/i915/gt/intel_rps.h

@@ -13,6 +13,7 @@ struct i915_request;
 
 void intel_rps_init_early(struct intel_rps *rps);
 void intel_rps_init(struct intel_rps *rps);
+void intel_rps_sanitize(struct intel_rps *rps);
 
 void intel_rps_driver_register(struct intel_rps *rps);
 void intel_rps_driver_unregister(struct intel_rps *rps);