drm/i915: Implement plane-disabled assertion for PCH too

Signed-off-by: Adam Jackson <ajax@redhat.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

1 files changed, 7 insertions, 1 deletions

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 5fa1476cbfc..d775f954c1b 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -970,8 +970,14 @@ static void assert_planes_disabled(struct drm_i915_private *dev_priv,
         int cur_pipe;
 
         /* Planes are fixed to pipes on ILK+ */
-        if (HAS_PCH_SPLIT(dev_priv->dev))
+        if (HAS_PCH_SPLIT(dev_priv->dev)) {
+                reg = DSPCNTR(pipe);
+                val = I915_READ(reg);
+                WARN((val & DISPLAY_PLANE_ENABLE),
+                     "plane %c assertion failure, should be disabled but not\n",
+                     plane_name(pipe));
                 return;
+        }
 
         /* Need to check both planes against the pipe */
         for (i = 0; i < 2; i++) {