Merge tag 'drm-intel-next-2014-09-05' of git://anongit.freedesktop.org/drm-intel into drm-next

- final bits (again) for the rotation support (Sonika Jindal)
- support bl_power in the intel backlight (Jani)
- vdd handling improvements from Ville
- i830M fixes from Ville
- piles of prep work all over to make skl enabling just plug in (Damien, Sonika)
- rename DP training defines to reflect latest edp standards, this touches all
  drm drivers supporting DP (Sonika Jindal)
- cache edids during single detect cycle to avoid re-reading it for e.g. audio,
  from Chris
- move w/a for registers which are stored in the hw context to the context init
  code (Arun&Damien)
- edp panel power sequencer fixes, helps chv a lot (Ville)
- piles of other chv fixes all over
- much more paranoid pageflip handling with stall detection and better recovery
  from Chris
- small things all over, as usual

* tag 'drm-intel-next-2014-09-05' of git://anongit.freedesktop.org/drm-intel: (114 commits)
  drm/i915: Update DRIVER_DATE to 20140905
  drm/i915: Decouple the stuck pageflip on modeset
  drm/i915: Check for a stalled page flip after each vblank
  drm/i915: Introduce a for_each_plane() macro
  drm/i915: Rewrite ABS_DIFF() in a safer manner
  drm/i915: Add comments explaining the vdd on/off functions
  drm/i915: Move DP port disable to post_disable for pch platforms
  drm/i915: Enable DP port earlier
  drm/i915: Turn on panel power before doing aux transfers
  drm/i915: Be more careful when picking the initial power sequencer pipe
  drm/i915: Reset power sequencer pipe tracking when disp2d is off
  drm/i915: Track which port is using which pipe's power sequencer
  drm/i915: Fix edp vdd locking
  drm/i915: Reset the HEAD pointer for the ring after writing START
  drm/i915: Fix unsafe vma iteration in i915_drop_caches
  drm/i915: init sprites with univeral plane init function
  drm/i915: Check of !HAS_PCH_SPLIT() in PCH transcoder funcs
  drm/i915: Use HAS_GMCH_DISPLAY un underrun reporting code
  drm/i915: Use IS_BROADWELL() instead of IS_GEN8() in forcewake code
  drm/i915: Don't call gen8_fbc_sw_flush() on chv
  ...

drivers/gpu/drm/i915/i915_gem.c

@@ -1085,7 +1085,13 @@ i915_gem_check_wedge(struct i915_gpu_error *error,
 		if (i915_terminally_wedged(error))
 			return -EIO;
 
-		return -EAGAIN;
+		/*
+		 * Check if GPU Reset is in progress - we need intel_ring_begin
+		 * to work properly to reinit the hw state while the gpu is
+		 * still marked as reset-in-progress. Handle this with a flag.
+		 */
+		if (!error->reload_in_reset)
+			return -EAGAIN;
 	}
 
 	return 0;
@@ -2982,9 +2988,11 @@ int i915_gpu_idle(struct drm_device *dev)
 
 	/* Flush everything onto the inactive list. */
 	for_each_ring(ring, dev_priv, i) {
-		ret = i915_switch_context(ring, ring->default_context);
-		if (ret)
-			return ret;
+		if (!i915.enable_execlists) {
+			ret = i915_switch_context(ring, ring->default_context);
+			if (ret)
+				return ret;
+		}
 
 		ret = intel_ring_idle(ring);
 		if (ret)
@@ -4658,11 +4666,46 @@ intel_enable_blt(struct drm_device *dev)
 	return true;
 }
 
+static void init_unused_ring(struct drm_device *dev, u32 base)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+
+	I915_WRITE(RING_CTL(base), 0);
+	I915_WRITE(RING_HEAD(base), 0);
+	I915_WRITE(RING_TAIL(base), 0);
+	I915_WRITE(RING_START(base), 0);
+}
+
+static void init_unused_rings(struct drm_device *dev)
+{
+	if (IS_I830(dev)) {
+		init_unused_ring(dev, PRB1_BASE);
+		init_unused_ring(dev, SRB0_BASE);
+		init_unused_ring(dev, SRB1_BASE);
+		init_unused_ring(dev, SRB2_BASE);
+		init_unused_ring(dev, SRB3_BASE);
+	} else if (IS_GEN2(dev)) {
+		init_unused_ring(dev, SRB0_BASE);
+		init_unused_ring(dev, SRB1_BASE);
+	} else if (IS_GEN3(dev)) {
+		init_unused_ring(dev, PRB1_BASE);
+		init_unused_ring(dev, PRB2_BASE);
+	}
+}
+
 int i915_gem_init_rings(struct drm_device *dev)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	int ret;
 
+	/*
+	 * At least 830 can leave some of the unused rings
+	 * "active" (ie. head != tail) after resume which
+	 * will prevent c3 entry. Makes sure all unused rings
+	 * are totally idle.
+	 */
+	init_unused_rings(dev);
+
 	ret = intel_init_render_ring_buffer(dev);
 	if (ret)
 		return ret;