drm/i915: Only save/restore FBC on the platform that supports FBC

Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>

drivers/gpu/drm/i915/i915_suspend.c

@@ -600,7 +600,8 @@ void i915_save_display(struct drm_device *dev)
 	}
 	/* FIXME: save TV & SDVO state */
 
-	/* FBC state */
+	/* Only save FBC state on the platform that supports FBC */
+	if (I915_HAS_FBC(dev)) {
 		if (IS_GM45(dev)) {
 			dev_priv->saveDPFC_CB_BASE = I915_READ(DPFC_CB_BASE);
 		} else {
@@ -609,6 +610,7 @@ void i915_save_display(struct drm_device *dev)
 			dev_priv->saveFBC_CONTROL2 = I915_READ(FBC_CONTROL2);
 			dev_priv->saveFBC_CONTROL = I915_READ(FBC_CONTROL);
 		}
+	}
 
 	/* VGA state */
 	dev_priv->saveVGA0 = I915_READ(VGA0);
@@ -702,7 +704,8 @@ void i915_restore_display(struct drm_device *dev)
 	}
 	/* FIXME: restore TV & SDVO state */
 
-	/* FBC info */
+	/* only restore FBC info on the platform that supports FBC*/
+	if (I915_HAS_FBC(dev)) {
 		if (IS_GM45(dev)) {
 			g4x_disable_fbc(dev);
 			I915_WRITE(DPFC_CB_BASE, dev_priv->saveDPFC_CB_BASE);
@@ -713,7 +716,7 @@ void i915_restore_display(struct drm_device *dev)
 			I915_WRITE(FBC_CONTROL2, dev_priv->saveFBC_CONTROL2);
 			I915_WRITE(FBC_CONTROL, dev_priv->saveFBC_CONTROL);
 		}
-
+	}
 	/* VGA state */
 	if (IS_IRONLAKE(dev))
 		I915_WRITE(CPU_VGACNTRL, dev_priv->saveVGACNTRL);