drm/i915: Simplify enabling user-interrupts with L3-remapping

Borrow the idea from intel_lrc.c to precompute the mask of interrupts we
wish to always enable to avoid having lots of conditionals inside the
interrupt enabling.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1467390209-3576-19-git-send-email-chris@chris-wilson.co.uk

drivers/gpu/drm/i915/intel_ringbuffer.c

@@ -1313,8 +1313,7 @@ static int init_render_ring(struct intel_engine_cs *engine)
 	if (IS_GEN(dev_priv, 6, 7))
 		I915_WRITE(INSTPM, _MASKED_BIT_ENABLE(INSTPM_FORCE_ORDERING));
 
-	if (HAS_L3_DPF(dev_priv))
-		I915_WRITE_IMR(engine, ~GT_PARITY_ERROR(dev_priv));
+	I915_WRITE_IMR(engine, ~engine->irq_keep_mask);
 
 	return init_workarounds_ring(engine);
 }
@@ -1729,12 +1728,9 @@ gen6_irq_enable(struct intel_engine_cs *engine)
 {
 	struct drm_i915_private *dev_priv = engine->i915;
 
-	if (HAS_L3_DPF(dev_priv) && engine->id == RCS)
-		I915_WRITE_IMR(engine,
-			       ~(engine->irq_enable_mask |
-				 GT_PARITY_ERROR(dev_priv)));
-	else
-		I915_WRITE_IMR(engine, ~engine->irq_enable_mask);
+	I915_WRITE_IMR(engine,
+		       ~(engine->irq_enable_mask |
+			 engine->irq_keep_mask));
 	gen5_enable_gt_irq(dev_priv, engine->irq_enable_mask);
 }
 
@@ -1743,10 +1739,7 @@ gen6_irq_disable(struct intel_engine_cs *engine)
 {
 	struct drm_i915_private *dev_priv = engine->i915;
 
-	if (HAS_L3_DPF(dev_priv) && engine->id == RCS)
-		I915_WRITE_IMR(engine, ~GT_PARITY_ERROR(dev_priv));
-	else
-		I915_WRITE_IMR(engine, ~0);
+	I915_WRITE_IMR(engine, ~engine->irq_keep_mask);
 	gen5_disable_gt_irq(dev_priv, engine->irq_enable_mask);
 }
 
@@ -1773,12 +1766,9 @@ gen8_irq_enable(struct intel_engine_cs *engine)
 {
 	struct drm_i915_private *dev_priv = engine->i915;
 
-	if (HAS_L3_DPF(dev_priv) && engine->id == RCS)
-		I915_WRITE_IMR(engine,
-			       ~(engine->irq_enable_mask |
-				 GT_RENDER_L3_PARITY_ERROR_INTERRUPT));
-	else
-		I915_WRITE_IMR(engine, ~engine->irq_enable_mask);
+	I915_WRITE_IMR(engine,
+		       ~(engine->irq_enable_mask |
+			 engine->irq_keep_mask));
 	POSTING_READ_FW(RING_IMR(engine->mmio_base));
 }
 
@@ -1787,11 +1777,7 @@ gen8_irq_disable(struct intel_engine_cs *engine)
 {
 	struct drm_i915_private *dev_priv = engine->i915;
 
-	if (HAS_L3_DPF(dev_priv) && engine->id == RCS)
-		I915_WRITE_IMR(engine,
-			       ~GT_RENDER_L3_PARITY_ERROR_INTERRUPT);
-	else
-		I915_WRITE_IMR(engine, ~0);
+	I915_WRITE_IMR(engine, ~engine->irq_keep_mask);
 }
 
 static int
@@ -2872,6 +2858,8 @@ int intel_init_render_ring_buffer(struct drm_device *dev)
 	intel_ring_default_vfuncs(dev_priv, engine);
 
 	engine->irq_enable_mask = GT_RENDER_USER_INTERRUPT;
+	if (HAS_L3_DPF(dev_priv))
+		engine->irq_keep_mask = GT_RENDER_L3_PARITY_ERROR_INTERRUPT;
 
 	if (INTEL_GEN(dev_priv) >= 8) {
 		engine->init_context = intel_rcs_ctx_init;

drivers/gpu/drm/i915/intel_ringbuffer.h

@@ -190,7 +190,8 @@ struct intel_engine_cs {
 	struct i915_ctx_workarounds wa_ctx;
 
 	bool		irq_posted;
-	u32		irq_enable_mask;	/* bitmask to enable ring interrupt */
+	u32             irq_keep_mask; /* always keep these interrupts */
+	u32		irq_enable_mask; /* bitmask to enable ring interrupt */
 	void		(*irq_enable)(struct intel_engine_cs *ring);
 	void		(*irq_disable)(struct intel_engine_cs *ring);
 
@@ -287,7 +288,6 @@ struct intel_engine_cs {
 	unsigned int idle_lite_restore_wa;
 	bool disable_lite_restore_wa;
 	u32 ctx_desc_template;
-	u32             irq_keep_mask; /* bitmask for interrupts that should not be masked */
 	int		(*emit_request)(struct drm_i915_gem_request *request);
 	int		(*emit_flush)(struct drm_i915_gem_request *request,
 				      u32 invalidate_domains,