Merge tag 'drm-intel-fixes-2015-05-13' of git://anongit.freedesktop.org/drm-intel into drm-fixes

fix one gpu hang on resume.

* tag 'drm-intel-fixes-2015-05-13' of git://anongit.freedesktop.org/drm-intel:
  drm/i915: Avoid GPU hang when coming out of s3 or s4

1 files changed, 10 insertions, 3 deletions

diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index c302ffb5a168..a19d2c71e205 100644
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -699,6 +699,16 @@ static int i915_drm_resume(struct drm_device *dev)
         intel_init_pch_refclk(dev);
         drm_mode_config_reset(dev);
 
+        /*
+         * Interrupts have to be enabled before any batches are run. If not the
+         * GPU will hang. i915_gem_init_hw() will initiate batches to
+         * update/restore the context.
+         *
+         * Modeset enabling in intel_modeset_init_hw() also needs working
+         * interrupts.
+         */
+        intel_runtime_pm_enable_interrupts(dev_priv);
+
         mutex_lock(&dev->struct_mutex);
         if (i915_gem_init_hw(dev)) {
                 DRM_ERROR("failed to re-initialize GPU, declaring wedged!\n");
@@ -706,9 +716,6 @@ static int i915_drm_resume(struct drm_device *dev)
         }
         mutex_unlock(&dev->struct_mutex);
 
-        /* We need working interrupts for modeset enabling ... */
-        intel_runtime_pm_enable_interrupts(dev_priv);
-
         intel_modeset_init_hw(dev);
 
         spin_lock_irq(&dev_priv->irq_lock);