drm/i915/icl: whitelist PS_(DEPTH|INVOCATION)_COUNT

The same tests failing on CFL+ platforms are also failing on ICL.
Documentation doesn't list the
WaAllowPMDepthAndInvocationCountAccessFromUMD workaround for ICL but
applying it fixes the same tests as CFL.

v2: Use only one whitelist entry (Lionel)
Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Tested-by: Anuj Phogat <anuj.phogat@gmail.com>
Cc: stable@vger.kernel.org
Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20190628120720.21682-4-lionel.g.landwerlin@intel.com

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

@@ -1138,6 +1138,19 @@ static void icl_whitelist_build(struct intel_engine_cs *engine)
 
 		/* WaEnableStateCacheRedirectToCS:icl */
 		whitelist_reg(w, GEN9_SLICE_COMMON_ECO_CHICKEN1);
+
+		/*
+		 * WaAllowPMDepthAndInvocationCountAccessFromUMD:icl
+		 *
+		 * This covers 4 register which are next to one another :
+		 *   - PS_INVOCATION_COUNT
+		 *   - PS_INVOCATION_COUNT_UDW
+		 *   - PS_DEPTH_COUNT
+		 *   - PS_DEPTH_COUNT_UDW
+		 */
+		whitelist_reg_ext(w, PS_INVOCATION_COUNT,
+				  RING_FORCE_TO_NONPRIV_RD |
+				  RING_FORCE_TO_NONPRIV_RANGE_4);
 		break;
 
 	case VIDEO_DECODE_CLASS: