drm/i915: Clear GDSR after reset on ILK

Clear the reset domain after a succesful GPU reset on ilk. We already
do that on gen4, so let's try to be a bit more consistent. And if
ether render or media reset fails, we might use the leftover value
in the register to pinpoint the culprit.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

diff --git a/drivers/gpu/drm/i915/intel_uncore.c b/drivers/gpu/drm/i915/intel_uncore.c
index b542bf6..4ec192b 100644 (file)
--- a/drivers/gpu/drm/i915/intel_uncore.c
+++ b/drivers/gpu/drm/i915/intel_uncore.c
@@ -1002,8 +1002,14 @@ static int ironlake_do_reset(struct drm_device *dev)
 
        I915_WRITE(MCHBAR_MIRROR_BASE + ILK_GDSR,
                   ILK_GRDOM_MEDIA | ILK_GRDOM_RESET_ENABLE);
-       return wait_for((I915_READ(MCHBAR_MIRROR_BASE + ILK_GDSR) &
-                        ILK_GRDOM_RESET_ENABLE) == 0, 500);
+       ret = wait_for((I915_READ(MCHBAR_MIRROR_BASE + ILK_GDSR) &
+                       ILK_GRDOM_RESET_ENABLE) == 0, 500);
+       if (ret)
+               return ret;
+
+       I915_WRITE(MCHBAR_MIRROR_BASE + ILK_GDSR, 0);
+
+       return 0;
 }
 
 static int gen6_do_reset(struct drm_device *dev)