drm/i915/gen9: Add WaSetDisablePixMaskCammingAndRhwoInCommonSliceChicken

In Indirect context w/a batch buffer,
+WaSetDisablePixMaskCammingAndRhwoInCommonSliceChicken

v2: SKL revision id was used for BXT, copy paste error found during
internal review (Bob Beckett).

v3: explain why part of the WA is in Per ctx batch (Mika)

Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Signed-off-by: NArun Siluvery <arun.siluvery@linux.intel.com>
Reviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/intel_lrc.c

@@ -1292,6 +1292,16 @@ static int gen9_init_perctx_bb(struct intel_engine_cs *ring,
 	struct drm_device *dev = ring->dev;
 	uint32_t index = wa_ctx_start(wa_ctx, *offset, CACHELINE_DWORDS);
 
+	/* WaSetDisablePixMaskCammingAndRhwoInCommonSliceChicken:skl,bxt */
+	if ((IS_SKYLAKE(dev) && (INTEL_REVID(dev) <= SKL_REVID_B0)) ||
+	    (IS_BROXTON(dev) && (INTEL_REVID(dev) == BXT_REVID_A0))) {
+		wa_ctx_emit(batch, index, MI_LOAD_REGISTER_IMM(1));
+		wa_ctx_emit(batch, index, GEN9_SLICE_COMMON_ECO_CHICKEN0);
+		wa_ctx_emit(batch, index,
+			    _MASKED_BIT_ENABLE(DISABLE_PIXEL_MASK_CAMMING));
+		wa_ctx_emit(batch, index, MI_NOOP);
+	}
+
 	/* WaDisableCtxRestoreArbitration:skl,bxt */
 	if ((IS_SKYLAKE(dev) && (INTEL_REVID(dev) <= SKL_REVID_D0)) ||
 	    (IS_BROXTON(dev) && (INTEL_REVID(dev) == BXT_REVID_A0)))

drivers/gpu/drm/i915/intel_ringbuffer.c

@@ -946,8 +946,11 @@ static int gen9_init_workarounds(struct intel_engine_cs *ring)
 		/* WaSetDisablePixMaskCammingAndRhwoInCommonSliceChicken:skl,bxt */
 		WA_SET_BIT_MASKED(GEN7_COMMON_SLICE_CHICKEN1,
 				  GEN9_RHWO_OPTIMIZATION_DISABLE);
-		WA_SET_BIT_MASKED(GEN9_SLICE_COMMON_ECO_CHICKEN0,
-				  DISABLE_PIXEL_MASK_CAMMING);
+		/*
+		 * WA also requires GEN9_SLICE_COMMON_ECO_CHICKEN0[14:14] to be set
+		 * but we do that in per ctx batchbuffer as there is an issue
+		 * with this register not getting restored on ctx restore
+		 */
 	}
 
 	if ((IS_SKYLAKE(dev) && INTEL_REVID(dev) >= SKL_REVID_C0) ||