diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 5e820fa91dba4f2253f255318ede7bda6ca85b25..b0bb1a5985546b3df30025a64fb445d227e77919 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -3470,6 +3470,7 @@
 
 #define GEN7_L3CNTLREG1				0xB01C
 #define  GEN7_WA_FOR_GEN7_L3_CONTROL			0x3C4FFF8C
+#define  GEN7_L3AGDIS				(1<<19)
 
 #define GEN7_L3_CHICKEN_MODE_REGISTER		0xB030
 #define  GEN7_WA_L3_CHICKEN_MODE				0x20000000
diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index 60d0404fe98b710698ac879c496e85a9da764e9c..a9e2c546de9a1896559c8551d3bc73f6036f6ebe 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -3677,7 +3677,7 @@ static void valleyview_init_clock_gating(struct drm_device *dev)
 		   GEN7_CSC1_RHWO_OPT_DISABLE_IN_RCC);
 
 	/* WaApplyL3ControlAndL3ChickenMode requires those two on Ivy Bridge */
-	I915_WRITE(GEN7_L3CNTLREG1, GEN7_WA_FOR_GEN7_L3_CONTROL);
+	I915_WRITE(GEN7_L3CNTLREG1, I915_READ(GEN7_L3CNTLREG1) | GEN7_L3AGDIS);
 	I915_WRITE(GEN7_L3_CHICKEN_MODE_REGISTER, GEN7_WA_L3_CHICKEN_MODE);
 
 	/* WaForceL3Serialization */