drm/i915/bxt: Add WaSetClckGatingDisableMedia

Signed-off-by: NArun Siluvery <arun.siluvery@linux.intel.com>
Reviewed-by: NSagar Arun Kamble <sagar.a.kamble@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/i915_reg.h

@@ -6897,6 +6897,7 @@ enum skl_disp_power_wells {
 #define   GEN7_DOP_CLOCK_GATE_ENABLE		(1<<0)
 #define   GEN8_DOP_CLOCK_GATE_CFCLK_ENABLE	(1<<2)
 #define   GEN8_DOP_CLOCK_GATE_GUC_ENABLE	(1<<4)
+#define   GEN8_DOP_CLOCK_GATE_MEDIA_ENABLE     (1<<6)
 
 #define GEN8_GARBCNTL                   0xB004
 #define   GEN9_GAPS_TSV_CREDIT_DISABLE  (1<<7)

drivers/gpu/drm/i915/intel_pm.c

@@ -134,6 +134,12 @@ static void bxt_init_clock_gating(struct drm_device *dev)
 		 */
 		I915_WRITE(TILECTL, I915_READ(TILECTL) | TILECTL_TLBPF);
 	}
+
+	/* WaSetClckGatingDisableMedia:bxt */
+	if (INTEL_REVID(dev) == BXT_REVID_A0) {
+		I915_WRITE(GEN7_MISCCPCTL, (I915_READ(GEN7_MISCCPCTL) &
+					    ~GEN8_DOP_CLOCK_GATE_MEDIA_ENABLE));
+	}
 }
 
 static void i915_pineview_get_mem_freq(struct drm_device *dev)