drm/i915: Disable pwrctx before unpin and free

Otherwise the chip may scribble over free memory.

Signed-off-by: Kristian Høgsberg <krh@bitplanet.net>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Eric Anholt <eric@anholt.net>

1 files changed, 5 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index abd24e2a4932..d2519f0136ef 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -4588,6 +4588,11 @@ void intel_modeset_cleanup(struct drm_device *dev)
                 dev_priv->display.disable_fbc(dev);
 
         if (dev_priv->pwrctx) {
+                struct drm_i915_gem_object *obj_priv;
+
+                obj_priv = dev_priv->pwrctx->driver_private;
+                I915_WRITE(PWRCTXA, obj_priv->gtt_offset &~ PWRCTX_EN);
+                I915_READ(PWRCTXA);
                 i915_gem_object_unpin(dev_priv->pwrctx);
                 drm_gem_object_unreference(dev_priv->pwrctx);
         }