drm/i915: Enable vebox interrupts

Similar to a patch originally written by:

v2: Reversed the meanings of masked and enabled (Haihao)
Made non-destructive writes in case enable/disabler rps runs first
(Haihao)

v3: Reword error message (Damien)
Modify postinstall to do the right thing based on previous fixup. (Ben)

CC: Xiang, Haihao <haihao.xiang@intel.com>
Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/i915_irq.c

@@ -944,8 +944,15 @@ static void hsw_pm_irq_handler(struct drm_i915_private *dev_priv,
 	}
 	spin_unlock_irqrestore(&dev_priv->rps.lock, flags);
 
-	if (pm_iir & ~GEN6_PM_RPS_EVENTS)
-		DRM_ERROR("Unexpected PM interrupted\n");
+	if (pm_iir & ~GEN6_PM_RPS_EVENTS) {
+		if (pm_iir & PM_VEBOX_USER_INTERRUPT)
+			notify_ring(dev_priv->dev, &dev_priv->ring[VECS]);
+
+		if (pm_iir & PM_VEBOX_CS_ERROR_INTERRUPT) {
+			DRM_ERROR("VEBOX CS error interrupt 0x%08x\n", pm_iir);
+			i915_handle_error(dev_priv->dev, false);
+		}
+	}
 }
 
 static irqreturn_t valleyview_irq_handler(int irq, void *arg)
@@ -2690,6 +2697,7 @@ static int ivybridge_irq_postinstall(struct drm_device *dev)
 		DE_PLANEA_FLIP_DONE_IVB |
 		DE_AUX_CHANNEL_A_IVB |
 		DE_ERR_INT_IVB;
+	u32 pm_irqs = GEN6_PM_RPS_EVENTS;
 	u32 gt_irqs;
 
 	dev_priv->irq_mask = ~display_mask;
@@ -2715,10 +2723,21 @@ static int ivybridge_irq_postinstall(struct drm_device *dev)
 	I915_WRITE(GTIER, gt_irqs);
 	POSTING_READ(GTIER);
 
-	/* Power management */
-	I915_WRITE(GEN6_PMIMR, ~GEN6_PM_RPS_EVENTS);
-	I915_WRITE(GEN6_PMIER, GEN6_PM_RPS_EVENTS);
-	POSTING_READ(GEN6_PMIMR);
+	I915_WRITE(GEN6_PMIIR, I915_READ(GEN6_PMIIR));
+	if (HAS_VEBOX(dev))
+		pm_irqs |= PM_VEBOX_USER_INTERRUPT |
+			PM_VEBOX_CS_ERROR_INTERRUPT;
+
+	/* Our enable/disable rps functions may touch these registers so
+	 * make sure to set a known state for only the non-RPS bits.
+	 * The RMW is extra paranoia since this should be called after being set
+	 * to a known state in preinstall.
+	 * */
+	I915_WRITE(GEN6_PMIMR,
+		   (I915_READ(GEN6_PMIMR) | ~GEN6_PM_RPS_EVENTS) & ~pm_irqs);
+	I915_WRITE(GEN6_PMIER,
+		   (I915_READ(GEN6_PMIER) & GEN6_PM_RPS_EVENTS) | pm_irqs);
+	POSTING_READ(GEN6_PMIER);
 
 	ibx_irq_postinstall(dev);
 

drivers/gpu/drm/i915/i915_reg.h

@@ -886,6 +886,9 @@
 #define GT_RENDER_DEBUG_INTERRUPT		(1 <<  1)
 #define GT_RENDER_USER_INTERRUPT		(1 <<  0)
 
+#define PM_VEBOX_CS_ERROR_INTERRUPT		(1 << 12) /* hsw+ */
+#define PM_VEBOX_USER_INTERRUPT			(1 << 10) /* hsw+ */
+
 /* These are all the "old" interrupts */
 #define ILK_BSD_USER_INTERRUPT				(1<<5)
 #define I915_PIPE_CONTROL_NOTIFY_INTERRUPT		(1<<18)

drivers/gpu/drm/i915/intel_ringbuffer.c

@@ -1969,7 +1969,8 @@ int intel_init_vebox_ring_buffer(struct drm_device *dev)
 	ring->add_request = gen6_add_request;
 	ring->get_seqno = gen6_ring_get_seqno;
 	ring->set_seqno = ring_set_seqno;
-	ring->irq_enable_mask = 0;
+	ring->irq_enable_mask = PM_VEBOX_USER_INTERRUPT |
+		PM_VEBOX_CS_ERROR_INTERRUPT;
 	ring->irq_get = hsw_vebox_get_irq;
 	ring->irq_put = hsw_vebox_put_irq;
 	ring->dispatch_execbuffer = gen6_ring_dispatch_execbuffer;