drm/i915: enable HiZ Raw Stall Optimization on IVB

The optimization helps IVB too.  No piglit regression.

Signed-off-by: Chia-I Wu <olv@lunarg.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
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 1a1eec6..3c79b63 100644 (file)
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -4866,6 +4866,10 @@ static void ivybridge_init_clock_gating(struct drm_device *dev)
 
        gen7_setup_fixed_func_scheduler(dev_priv);
 
+       /* enable HiZ Raw Stall Optimization */
+       I915_WRITE(CACHE_MODE_0_GEN7,
+                  _MASKED_BIT_DISABLE(HIZ_RAW_STALL_OPT_DISABLE));
+
        /* WaDisable4x2SubspanOptimization:ivb */
        I915_WRITE(CACHE_MODE_1,
                   _MASKED_BIT_ENABLE(PIXEL_SUBSPAN_COLLECT_OPT_DISABLE));