drm/i915: Add thread stall DOP clock gating workaround on Broadwell.
Ben and I believe this will be necessary on production hardware.
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
[danvet: Shuffle lines to group all ROW_CHICKEN writes and add a
cautious comment that this might not be needed on production hw.]
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index f21c9f3..bb2ca35 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -4805,6 +4805,11 @@
I915_WRITE(GEN8_ROW_CHICKEN,
_MASKED_BIT_ENABLE(PARTIAL_INSTRUCTION_SHOOTDOWN_DISABLE));
+ /* WaDisableThreadStallDopClockGating:bdw */
+ /* FIXME: Unclear whether we really need this on production bdw. */
+ I915_WRITE(GEN8_ROW_CHICKEN,
+ _MASKED_BIT_ENABLE(STALL_DOP_GATING_DISABLE));
+
/*
* This GEN8_CENTROID_PIXEL_OPT_DIS W/A is only needed for
* pre-production hardware