Merge tag 'drm-intel-next-2017-10-12' of git://anongit.freedesktop.org/drm/drm-intel into drm-next

Last batch of drm/i915 features for v4.15:

- transparent huge pages support (Matthew)
- uapi: I915_PARAM_HAS_SCHEDULER into a capability bitmask (Chris)
- execlists: preemption (Chris)
- scheduler: user defined priorities (Chris)
- execlists optimization (Michał)
- plenty of display fixes (Imre)
- has_ipc fix (Rodrigo)
- platform features definition refactoring (Rodrigo)
- legacy cursor update fix (Maarten)
- fix vblank waits for cursor updates (Maarten)
- reprogram dmc firmware on resume, dmc state fix (Imre)
- remove use_mmio_flip module parameter (Maarten)
- wa fixes (Oscar)
- huc/guc firmware refacoring (Sagar, Michal)
- push encoder specific code to encoder hooks (Jani)
- DP MST fixes (Dhinakaran)
- eDP power sequencing fixes (Manasi)
- selftest updates (Chris, Matthew)
- mmu notifier cpu hotplug deadlock fix (Daniel)
- more VBT parser refactoring (Jani)
- max pipe refactoring (Mika Kahola)
- rc6/rps refactoring and separation (Sagar)
- userptr lockdep fix (Chris)
- tracepoint fixes and defunct tracepoint removal (Chris)
- use rcu instead of abusing stop_machine (Daniel)
- plenty of other fixes all around (Everyone)

* tag 'drm-intel-next-2017-10-12' of git://anongit.freedesktop.org/drm/drm-intel: (145 commits)
  drm/i915: Update DRIVER_DATE to 20171012
  drm/i915: Simplify intel_sanitize_enable_ppgtt
  drm/i915/userptr: Drop struct_mutex before cleanup
  drm/i915/dp: limit sink rates based on rate
  drm/i915/dp: centralize max source rate conditions more
  drm/i915: Allow PCH platforms fall back to BIOS LVDS mode
  drm/i915: Reuse normal state readout for LVDS/DVO fixed mode
  drm/i915: Use rcu instead of stop_machine in set_wedged
  drm/i915: Introduce separate status variable for RC6 and LLC ring frequency setup
  drm/i915: Create generic functions to control RC6, RPS
  drm/i915: Create generic function to setup LLC ring frequency table
  drm/i915: Rename intel_enable_rc6 to intel_rc6_enabled
  drm/i915: Name structure in dev_priv that contains RPS/RC6 state as "gt_pm"
  drm/i915: Move rps.hw_lock to dev_priv and s/hw_lock/pcu_lock
  drm/i915: Name i915_runtime_pm structure in dev_priv as "runtime_pm"
  drm/i915: Separate RPS and RC6 handling for CHV
  drm/i915: Separate RPS and RC6 handling for VLV
  drm/i915: Separate RPS and RC6 handling for BDW
  drm/i915: Remove superfluous IS_BDW checks and non-BDW changes from gen8_enable_rps
  drm/i915: Separate RPS and RC6 handling for gen6+
  ...

1 files changed, 10 insertions, 1 deletions

diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
index 05c08b0bc172..4285f09ff8b8 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -579,7 +579,16 @@ out:
 static void reset_ring_common(struct intel_engine_cs *engine,
 			      struct drm_i915_gem_request *request)
 {
-	/* Try to restore the logical GPU state to match the continuation
+	/*
+	 * RC6 must be prevented until the reset is complete and the engine
+	 * reinitialised. If it occurs in the middle of this sequence, the
+	 * state written to/loaded from the power context is ill-defined (e.g.
+	 * the PP_BASE_DIR may be lost).
+	 */
+	assert_forcewakes_active(engine->i915, FORCEWAKE_ALL);
+
+	/*
+	 * Try to restore the logical GPU state to match the continuation
 	 * of the request queue. If we skip the context/PD restore, then
 	 * the next request may try to execute assuming that its context
 	 * is valid and loaded on the GPU and so may try to access invalid