diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 87e9b34..8952500 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -4756,7 +4756,7 @@
 	init_waitqueue_head(&dev_priv->gpu_error.reset_queue);
 
 	/* On GEN3 we really need to make sure the ARB C3 LP bit is set */
-	if (IS_GEN3(dev)) {
+	if (!drm_core_check_feature(dev, DRIVER_MODESET) && IS_GEN3(dev)) {
 		I915_WRITE(MI_ARB_STATE,
 			   _MASKED_BIT_ENABLE(MI_ARB_C3_LP_WRITE_ENABLE));
 	}
diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index b124ba4..f6fd86a 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -5507,6 +5507,9 @@
 
 	/* interrupts should cause a wake up from C3 */
 	I915_WRITE(INSTPM, _MASKED_BIT_ENABLE(INSTPM_AGPBUSY_INT_EN));
+
+	/* On GEN3 we really need to make sure the ARB C3 LP bit is set */
+	I915_WRITE(MI_ARB_STATE, _MASKED_BIT_ENABLE(MI_ARB_C3_LP_WRITE_ENABLE));
 }
 
 static void i85x_init_clock_gating(struct drm_device *dev)