drm/i915/skl: Implement WaCcsTlbPrefetchDisable:skl

Signed-off-by: NDamien Lespiau <damien.lespiau@intel.com>
Reviewed-by: NNick Hoath <nicholas.hoath@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/i915_reg.h

@@ -6209,6 +6209,7 @@ enum skl_disp_power_wells {
 
 #define GEN9_HALF_SLICE_CHICKEN5	0xe188
 #define   GEN9_DG_MIRROR_FIX_ENABLE	(1<<5)
+#define   GEN9_CCS_TLB_PREFETCH_ENABLE	(1<<3)
 
 #define GEN8_ROW_CHICKEN		0xe4f0
 #define   PARTIAL_INSTRUCTION_SHOOTDOWN_DISABLE	(1<<8)

drivers/gpu/drm/i915/intel_ringbuffer.c

@@ -984,6 +984,10 @@ static int gen9_init_workarounds(struct intel_engine_cs *ring)
 	/* WaDisablePartialResolveInVc:skl */
 	WA_SET_BIT_MASKED(CACHE_MODE_1, GEN9_PARTIAL_RESOLVE_IN_VC_DISABLE);
 
+	/* WaCcsTlbPrefetchDisable:skl */
+	WA_CLR_BIT_MASKED(GEN9_HALF_SLICE_CHICKEN5,
+			  GEN9_CCS_TLB_PREFETCH_ENABLE);
+
 	return 0;
 }