drm/i915: Combined gt.awake/gt.power wakerefs

As the GT_IRQ power domain implies a wakeref, we can use it inplace of
our existing redundant rpm grab.

v2: Drop papering over forgetting to take the runtime wakeref in
selftests

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190114142129.24398-20-chris@chris-wilson.co.uk

drivers/gpu/drm/i915/i915_drv.h

@@ -1985,7 +1985,6 @@ struct drm_i915_private {
 		 * is a slight delay before we do so.
 		 */
 		intel_wakeref_t awake;
-		intel_wakeref_t power;
 
 		/**
 		 * The number of times we have woken up.

drivers/gpu/drm/i915/i915_gem.c

@@ -176,9 +176,7 @@ static u32 __i915_gem_park(struct drm_i915_private *i915)
 	if (INTEL_GEN(i915) >= 6)
 		gen6_rps_idle(i915);
 
-	intel_display_power_put(i915, POWER_DOMAIN_GT_IRQ, i915->gt.power);
-
-	intel_runtime_pm_put(i915, wakeref);
+	intel_display_power_put(i915, POWER_DOMAIN_GT_IRQ, wakeref);
 
 	return i915->gt.epoch;
 }
@@ -203,13 +201,11 @@ void i915_gem_unpark(struct drm_i915_private *i915)
 
 	lockdep_assert_held(&i915->drm.struct_mutex);
 	GEM_BUG_ON(!i915->gt.active_requests);
+	assert_rpm_wakelock_held(i915);
 
 	if (i915->gt.awake)
 		return;
 
-	i915->gt.awake = intel_runtime_pm_get_noresume(i915);
-	GEM_BUG_ON(!i915->gt.awake);
-
 	/*
 	 * It seems that the DMC likes to transition between the DC states a lot
 	 * when there are no connected displays (no active power domains) during
@@ -221,7 +217,8 @@ void i915_gem_unpark(struct drm_i915_private *i915)
 	 * Work around it by grabbing a GT IRQ power domain whilst there is any
 	 * GT activity, preventing any DC state transitions.
 	 */
-	i915->gt.power = intel_display_power_get(i915, POWER_DOMAIN_GT_IRQ);
+	i915->gt.awake = intel_display_power_get(i915, POWER_DOMAIN_GT_IRQ);
+	GEM_BUG_ON(!i915->gt.awake);
 
 	if (unlikely(++i915->gt.epoch == 0)) /* keep 0 as invalid */
 		i915->gt.epoch = 1;

drivers/gpu/drm/i915/intel_lrc.c

@@ -1045,7 +1045,7 @@ static void execlists_submission_tasklet(unsigned long data)
 
 	GEM_TRACE("%s awake?=%d, active=%x\n",
 		  engine->name,
-		  engine->i915->gt.awake,
+		  !!engine->i915->gt.awake,
 		  engine->execlists.active);
 
 	spin_lock_irqsave(&engine->timeline.lock, flags);