[Intel-gfx] [PATCH] drm/i915/gen9: implement WaEnableSamplerGPGPUPreemptionSupport

[tim.gore at intel.com]

From: Tim Gore <tim.gore at intel.com>

WaEnableSamplerGPGPUPreemptionSupport fixes a problem
related to mid thread pre-emption.

Signed-off-by: Tim Gore <tim.gore at intel.com>
---
 drivers/gpu/drm/i915/i915_reg.h         | 1 +
 drivers/gpu/drm/i915/intel_ringbuffer.c | 7 ++++---
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 30fea34..de83914 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -7142,6 +7142,7 @@ enum skl_disp_power_wells {
 
 #define GEN9_HALF_SLICE_CHICKEN7	_MMIO(0xe194)
 #define   GEN9_ENABLE_YV12_BUGFIX	(1<<4)
+#define   GEN9_ENABLE_GPGPU_PREEMPTION	(1<<2)
 
 /* Audio */
 #define G4X_AUD_VID_DID			_MMIO(dev_priv->info.display_mmio_offset + 0x62020)
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
index 2e864b7..0b4f582 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -959,9 +959,10 @@ static int gen9_init_workarounds(struct intel_engine_cs *engine)
 	}
 
 	/* WaEnableYV12BugFixInHalfSliceChicken7:skl,bxt */
-	if (IS_SKL_REVID(dev, SKL_REVID_C0, REVID_FOREVER) || IS_BROXTON(dev))
-		WA_SET_BIT_MASKED(GEN9_HALF_SLICE_CHICKEN7,
-				  GEN9_ENABLE_YV12_BUGFIX);
+	/* WaEnableSamplerGPGPUPreemptionSupport:skl,bxt */
+	WA_SET_BIT_MASKED(GEN9_HALF_SLICE_CHICKEN7,
+			  GEN9_ENABLE_YV12_BUGFIX |
+			  GEN9_ENABLE_GPGPU_PREEMPTION);
 
 	/* Wa4x4STCOptimizationDisable:skl,bxt */
 	/* WaDisablePartialResolveInVc:skl,bxt */
-- 
1.9.1