1 files changed, 169 insertions, 507 deletions

diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index 26f48932a51e..69b9a42da95e 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -33,11 +33,23 @@
 
 #define MAX_NOPID ((u32)~0)
 
-/** These are the interrupts used by the driver */
-#define I915_INTERRUPT_ENABLE_MASK (I915_USER_INTERRUPT |		\
-				    I915_ASLE_INTERRUPT |		\
-				    I915_DISPLAY_PIPE_A_EVENT_INTERRUPT | \
-				    I915_DISPLAY_PIPE_B_EVENT_INTERRUPT)
+/**
+ * Interrupts that are always left unmasked.
+ *
+ * Since pipe events are edge-triggered from the PIPESTAT register to IIR,
+ * we leave them always unmasked in IMR and then control enabling them through
+ * PIPESTAT alone.
+ */
+#define I915_INTERRUPT_ENABLE_FIX (I915_ASLE_INTERRUPT | \
+				   I915_DISPLAY_PIPE_A_EVENT_INTERRUPT |  \
+				   I915_DISPLAY_PIPE_B_EVENT_INTERRUPT)
+
+/** Interrupts that we mask and unmask at runtime. */
+#define I915_INTERRUPT_ENABLE_VAR (I915_USER_INTERRUPT)
+
+/** These are all of the interrupts used by the driver */
+#define I915_INTERRUPT_ENABLE_MASK (I915_INTERRUPT_ENABLE_FIX | \
+				    I915_INTERRUPT_ENABLE_VAR)
 
 void
 i915_enable_irq(drm_i915_private_t *dev_priv, u32 mask)
@@ -59,6 +71,41 @@ i915_disable_irq(drm_i915_private_t *dev_priv, u32 mask)
 	}
 }
 
+static inline u32
+i915_pipestat(int pipe)
+{
+	if (pipe == 0)
+		return PIPEASTAT;
+	if (pipe == 1)
+		return PIPEBSTAT;
+	BUG();
+}
+
+void
+i915_enable_pipestat(drm_i915_private_t *dev_priv, int pipe, u32 mask)
+{
+	if ((dev_priv->pipestat[pipe] & mask) != mask) {
+		u32 reg = i915_pipestat(pipe);
+
+		dev_priv->pipestat[pipe] |= mask;
+		/* Enable the interrupt, clear any pending status */
+		I915_WRITE(reg, dev_priv->pipestat[pipe] | (mask >> 16));
+		(void) I915_READ(reg);
+	}
+}
+
+void
+i915_disable_pipestat(drm_i915_private_t *dev_priv, int pipe, u32 mask)
+{
+	if ((dev_priv->pipestat[pipe] & mask) != 0) {
+		u32 reg = i915_pipestat(pipe);
+
+		dev_priv->pipestat[pipe] &= ~mask;
+		I915_WRITE(reg, dev_priv->pipestat[pipe]);
+		(void) I915_READ(reg);
+	}
+}
+
 /**
  * i915_pipe_enabled - check if a pipe is enabled
  * @dev: DRM device
@@ -80,211 +127,6 @@ i915_pipe_enabled(struct drm_device *dev, int pipe)
 	return 0;
 }
 
-/**
- * Emit blits for scheduled buffer swaps.
- *
- * This function will be called with the HW lock held.
- * Because this function must grab the ring mutex (dev->struct_mutex),
- * it can no longer run at soft irq time. We'll fix this when we do
- * the DRI2 swap buffer work.
- */
-static void i915_vblank_tasklet(struct drm_device *dev)
-{
-	drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
-	unsigned long irqflags;
-	struct list_head *list, *tmp, hits, *hit;
-	int nhits, nrects, slice[2], upper[2], lower[2], i;
-	unsigned counter[2];
-	struct drm_drawable_info *drw;
-	drm_i915_sarea_t *sarea_priv = dev_priv->sarea_priv;
-	u32 cpp = dev_priv->cpp;
-	u32 cmd = (cpp == 4) ? (XY_SRC_COPY_BLT_CMD |
-				XY_SRC_COPY_BLT_WRITE_ALPHA |
-				XY_SRC_COPY_BLT_WRITE_RGB)
-			     : XY_SRC_COPY_BLT_CMD;
-	u32 src_pitch = sarea_priv->pitch * cpp;
-	u32 dst_pitch = sarea_priv->pitch * cpp;
-	u32 ropcpp = (0xcc << 16) | ((cpp - 1) << 24);
-	RING_LOCALS;
-
-	mutex_lock(&dev->struct_mutex);
-
-	if (IS_I965G(dev) && sarea_priv->front_tiled) {
-		cmd |= XY_SRC_COPY_BLT_DST_TILED;
-		dst_pitch >>= 2;
-	}
-	if (IS_I965G(dev) && sarea_priv->back_tiled) {
-		cmd |= XY_SRC_COPY_BLT_SRC_TILED;
-		src_pitch >>= 2;
-	}
-
-	counter[0] = drm_vblank_count(dev, 0);
-	counter[1] = drm_vblank_count(dev, 1);
-
-	DRM_DEBUG("\n");
-
-	INIT_LIST_HEAD(&hits);
-
-	nhits = nrects = 0;
-
-	spin_lock_irqsave(&dev_priv->swaps_lock, irqflags);
-
-	/* Find buffer swaps scheduled for this vertical blank */
-	list_for_each_safe(list, tmp, &dev_priv->vbl_swaps.head) {
-		drm_i915_vbl_swap_t *vbl_swap =
-			list_entry(list, drm_i915_vbl_swap_t, head);
-		int pipe = vbl_swap->pipe;
-
-		if ((counter[pipe] - vbl_swap->sequence) > (1<<23))
-			continue;
-
-		list_del(list);
-		dev_priv->swaps_pending--;
-		drm_vblank_put(dev, pipe);
-
-		spin_unlock(&dev_priv->swaps_lock);
-		spin_lock(&dev->drw_lock);
-
-		drw = drm_get_drawable_info(dev, vbl_swap->drw_id);
-
-		list_for_each(hit, &hits) {
-			drm_i915_vbl_swap_t *swap_cmp =
-				list_entry(hit, drm_i915_vbl_swap_t, head);
-			struct drm_drawable_info *drw_cmp =
-				drm_get_drawable_info(dev, swap_cmp->drw_id);
-
-			/* Make sure both drawables are still
-			 * around and have some rectangles before
-			 * we look inside to order them for the
-			 * blts below.
-			 */
-			if (drw_cmp && drw_cmp->num_rects > 0 &&
-			    drw && drw->num_rects > 0 &&
-			    drw_cmp->rects[0].y1 > drw->rects[0].y1) {
-				list_add_tail(list, hit);
-				break;
-			}
-		}
-
-		spin_unlock(&dev->drw_lock);
-
-		/* List of hits was empty, or we reached the end of it */
-		if (hit == &hits)
-			list_add_tail(list, hits.prev);
-
-		nhits++;
-
-		spin_lock(&dev_priv->swaps_lock);
-	}
-
-	if (nhits == 0) {
-		spin_unlock_irqrestore(&dev_priv->swaps_lock, irqflags);
-		mutex_unlock(&dev->struct_mutex);
-		return;
-	}
-
-	spin_unlock(&dev_priv->swaps_lock);
-
-	i915_kernel_lost_context(dev);
-
-	if (IS_I965G(dev)) {
-		BEGIN_LP_RING(4);
-
-		OUT_RING(GFX_OP_DRAWRECT_INFO_I965);
-		OUT_RING(0);
-		OUT_RING(((sarea_priv->width - 1) & 0xffff) | ((sarea_priv->height - 1) << 16));
-		OUT_RING(0);
-		ADVANCE_LP_RING();
-	} else {
-		BEGIN_LP_RING(6);
-
-		OUT_RING(GFX_OP_DRAWRECT_INFO);
-		OUT_RING(0);
-		OUT_RING(0);
-		OUT_RING(sarea_priv->width | sarea_priv->height << 16);
-		OUT_RING(sarea_priv->width | sarea_priv->height << 16);
-		OUT_RING(0);
-
-		ADVANCE_LP_RING();
-	}
-
-	sarea_priv->ctxOwner = DRM_KERNEL_CONTEXT;
-
-	upper[0] = upper[1] = 0;
-	slice[0] = max(sarea_priv->pipeA_h / nhits, 1);
-	slice[1] = max(sarea_priv->pipeB_h / nhits, 1);
-	lower[0] = sarea_priv->pipeA_y + slice[0];
-	lower[1] = sarea_priv->pipeB_y + slice[0];
-
-	spin_lock(&dev->drw_lock);
-
-	/* Emit blits for buffer swaps, partitioning both outputs into as many
-	 * slices as there are buffer swaps scheduled in order to avoid tearing
-	 * (based on the assumption that a single buffer swap would always
-	 * complete before scanout starts).
-	 */
-	for (i = 0; i++ < nhits;
-	     upper[0] = lower[0], lower[0] += slice[0],
-	     upper[1] = lower[1], lower[1] += slice[1]) {
-		if (i == nhits)
-			lower[0] = lower[1] = sarea_priv->height;
-
-		list_for_each(hit, &hits) {
-			drm_i915_vbl_swap_t *swap_hit =
-				list_entry(hit, drm_i915_vbl_swap_t, head);
-			struct drm_clip_rect *rect;
-			int num_rects, pipe;
-			unsigned short top, bottom;
-
-			drw = drm_get_drawable_info(dev, swap_hit->drw_id);
-
-			/* The drawable may have been destroyed since
-			 * the vblank swap was queued
-			 */
-			if (!drw)
-				continue;
-
-			rect = drw->rects;
-			pipe = swap_hit->pipe;
-			top = upper[pipe];
-			bottom = lower[pipe];
-
-			for (num_rects = drw->num_rects; num_rects--; rect++) {
-				int y1 = max(rect->y1, top);
-				int y2 = min(rect->y2, bottom);
-
-				if (y1 >= y2)
-					continue;
-
-				BEGIN_LP_RING(8);
-
-				OUT_RING(cmd);
-				OUT_RING(ropcpp | dst_pitch);
-				OUT_RING((y1 << 16) | rect->x1);
-				OUT_RING((y2 << 16) | rect->x2);
-				OUT_RING(sarea_priv->front_offset);
-				OUT_RING((y1 << 16) | rect->x1);
-				OUT_RING(src_pitch);
-				OUT_RING(sarea_priv->back_offset);
-
-				ADVANCE_LP_RING();
-			}
-		}
-	}
-
-	spin_unlock_irqrestore(&dev->drw_lock, irqflags);
-	mutex_unlock(&dev->struct_mutex);
-
-	list_for_each_safe(hit, tmp, &hits) {
-		drm_i915_vbl_swap_t *swap_hit =
-			list_entry(hit, drm_i915_vbl_swap_t, head);
-
-		list_del(hit);
-
-		drm_free(swap_hit, sizeof(*swap_hit), DRM_MEM_DRIVER);
-	}
-}
-
 /* Called from drm generic code, passed a 'crtc', which
  * we use as a pipe index
  */
@@ -322,121 +164,106 @@ u32 i915_get_vblank_counter(struct drm_device *dev, int pipe)
 	return count;
 }
 
-void
-i915_vblank_work_handler(struct work_struct *work)
-{
-	drm_i915_private_t *dev_priv = container_of(work, drm_i915_private_t,
-						    vblank_work);
-	struct drm_device *dev = dev_priv->dev;
-	unsigned long irqflags;
-
-	if (dev->lock.hw_lock == NULL) {
-		i915_vblank_tasklet(dev);
-		return;
-	}
-
-	spin_lock_irqsave(&dev->tasklet_lock, irqflags);
-	dev->locked_tasklet_func = i915_vblank_tasklet;
-	spin_unlock_irqrestore(&dev->tasklet_lock, irqflags);
-
-	/* Try to get the lock now, if this fails, the lock
-	 * holder will execute the tasklet during unlock
-	 */
-	if (!drm_lock_take(&dev->lock, DRM_KERNEL_CONTEXT))
-		return;
-
-	dev->lock.lock_time = jiffies;
-	atomic_inc(&dev->counts[_DRM_STAT_LOCKS]);
-
-	spin_lock_irqsave(&dev->tasklet_lock, irqflags);
-	dev->locked_tasklet_func = NULL;
-	spin_unlock_irqrestore(&dev->tasklet_lock, irqflags);
-
-	i915_vblank_tasklet(dev);
-	drm_lock_free(&dev->lock, DRM_KERNEL_CONTEXT);
-}
-
 irqreturn_t i915_driver_irq_handler(DRM_IRQ_ARGS)
 {
 	struct drm_device *dev = (struct drm_device *) arg;
 	drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
-	u32 iir;
+	u32 iir, new_iir;
 	u32 pipea_stats, pipeb_stats;
+	u32 vblank_status;
+	u32 vblank_enable;
 	int vblank = 0;
+	unsigned long irqflags;
+	int irq_received;
+	int ret = IRQ_NONE;
 
 	atomic_inc(&dev_priv->irq_received);
 
-	if (dev->pdev->msi_enabled)
-		I915_WRITE(IMR, ~0);
 	iir = I915_READ(IIR);
 
-	if (iir == 0) {
-		if (dev->pdev->msi_enabled) {
-			I915_WRITE(IMR, dev_priv->irq_mask_reg);
-			(void) I915_READ(IMR);
-		}
-		return IRQ_NONE;
+	if (IS_I965G(dev)) {
+		vblank_status = I915_START_VBLANK_INTERRUPT_STATUS;
+		vblank_enable = PIPE_START_VBLANK_INTERRUPT_ENABLE;
+	} else {
+		vblank_status = I915_VBLANK_INTERRUPT_STATUS;
+		vblank_enable = I915_VBLANK_INTERRUPT_ENABLE;
 	}
 
-	/*
-	 * Clear the PIPE(A|B)STAT regs before the IIR otherwise
-	 * we may get extra interrupts.
-	 */
-	if (iir & I915_DISPLAY_PIPE_A_EVENT_INTERRUPT) {
+	for (;;) {
+		irq_received = iir != 0;
+
+		/* Can't rely on pipestat interrupt bit in iir as it might
+		 * have been cleared after the pipestat interrupt was received.
+		 * It doesn't set the bit in iir again, but it still produces
+		 * interrupts (for non-MSI).
+		 */
+		spin_lock_irqsave(&dev_priv->user_irq_lock, irqflags);
 		pipea_stats = I915_READ(PIPEASTAT);
-		if (!(dev_priv->vblank_pipe & DRM_I915_VBLANK_PIPE_A))
-			pipea_stats &= ~(PIPE_START_VBLANK_INTERRUPT_ENABLE |
-					 PIPE_VBLANK_INTERRUPT_ENABLE);
-		else if (pipea_stats & (PIPE_START_VBLANK_INTERRUPT_STATUS|
-					PIPE_VBLANK_INTERRUPT_STATUS)) {
+		pipeb_stats = I915_READ(PIPEBSTAT);
+		/*
+		 * Clear the PIPE(A|B)STAT regs before the IIR
+		 */
+		if (pipea_stats & 0x8000ffff) {
+			I915_WRITE(PIPEASTAT, pipea_stats);
+			irq_received = 1;
+		}
+
+		if (pipeb_stats & 0x8000ffff) {
+			I915_WRITE(PIPEBSTAT, pipeb_stats);
+			irq_received = 1;
+		}
+		spin_unlock_irqrestore(&dev_priv->user_irq_lock, irqflags);
+
+		if (!irq_received)
+			break;
+
+		ret = IRQ_HANDLED;
+
+		I915_WRITE(IIR, iir);
+		new_iir = I915_READ(IIR); /* Flush posted writes */
+
+		if (dev_priv->sarea_priv)
+			dev_priv->sarea_priv->last_dispatch =
+				READ_BREADCRUMB(dev_priv);
+
+		if (iir & I915_USER_INTERRUPT) {
+			dev_priv->mm.irq_gem_seqno = i915_get_gem_seqno(dev);
+			DRM_WAKEUP(&dev_priv->irq_queue);
+		}
+
+		if (pipea_stats & vblank_status) {
 			vblank++;
 			drm_handle_vblank(dev, 0);
 		}
 
-		I915_WRITE(PIPEASTAT, pipea_stats);
-	}
-	if (iir & I915_DISPLAY_PIPE_B_EVENT_INTERRUPT) {
-		pipeb_stats = I915_READ(PIPEBSTAT);
-		/* Ack the event */
-		I915_WRITE(PIPEBSTAT, pipeb_stats);
-
-		/* The vblank interrupt gets enabled even if we didn't ask for
-		   it, so make sure it's shut down again */
-		if (!(dev_priv->vblank_pipe & DRM_I915_VBLANK_PIPE_B))
-			pipeb_stats &= ~(PIPE_START_VBLANK_INTERRUPT_ENABLE |
-					 PIPE_VBLANK_INTERRUPT_ENABLE);
-		else if (pipeb_stats & (PIPE_START_VBLANK_INTERRUPT_STATUS|
-					PIPE_VBLANK_INTERRUPT_STATUS)) {
+		if (pipeb_stats & vblank_status) {
 			vblank++;
 			drm_handle_vblank(dev, 1);
 		}
 
-		if (pipeb_stats & I915_LEGACY_BLC_EVENT_STATUS)
+		if ((pipeb_stats & I915_LEGACY_BLC_EVENT_STATUS) ||
+		    (iir & I915_ASLE_INTERRUPT))
 			opregion_asle_intr(dev);
-		I915_WRITE(PIPEBSTAT, pipeb_stats);
-	}
-
-	I915_WRITE(IIR, iir);
-	if (dev->pdev->msi_enabled)
-		I915_WRITE(IMR, dev_priv->irq_mask_reg);
-	(void) I915_READ(IIR); /* Flush posted writes */
-
-	if (dev_priv->sarea_priv)
-		dev_priv->sarea_priv->last_dispatch =
-			READ_BREADCRUMB(dev_priv);
 
-	if (iir & I915_USER_INTERRUPT) {
-		dev_priv->mm.irq_gem_seqno = i915_get_gem_seqno(dev);
-		DRM_WAKEUP(&dev_priv->irq_queue);
+		/* With MSI, interrupts are only generated when iir
+		 * transitions from zero to nonzero.  If another bit got
+		 * set while we were handling the existing iir bits, then
+		 * we would never get another interrupt.
+		 *
+		 * This is fine on non-MSI as well, as if we hit this path
+		 * we avoid exiting the interrupt handler only to generate
+		 * another one.
+		 *
+		 * Note that for MSI this could cause a stray interrupt report
+		 * if an interrupt landed in the time between writing IIR and
+		 * the posting read.  This should be rare enough to never
+		 * trigger the 99% of 100,000 interrupts test for disabling
+		 * stray interrupts.
+		 */
+		iir = new_iir;
 	}
 
-	if (iir & I915_ASLE_INTERRUPT)
-		opregion_asle_intr(dev);
-
-	if (vblank && dev_priv->swaps_pending > 0)
-		schedule_work(&dev_priv->vblank_work);
-
-	return IRQ_HANDLED;
+	return ret;
 }
 
 static int i915_emit_irq(struct drm_device * dev)
@@ -454,12 +281,10 @@ static int i915_emit_irq(struct drm_device * dev)
 	if (dev_priv->sarea_priv)
 		dev_priv->sarea_priv->last_enqueue = dev_priv->counter;
 
-	BEGIN_LP_RING(6);
+	BEGIN_LP_RING(4);
 	OUT_RING(MI_STORE_DWORD_INDEX);
-	OUT_RING(5 << MI_STORE_DWORD_INDEX_SHIFT);
+	OUT_RING(I915_BREADCRUMB_INDEX << MI_STORE_DWORD_INDEX_SHIFT);
 	OUT_RING(dev_priv->counter);
-	OUT_RING(0);
-	OUT_RING(0);
 	OUT_RING(MI_USER_INTERRUPT);
 	ADVANCE_LP_RING();
 
@@ -574,48 +399,16 @@ int i915_irq_wait(struct drm_device *dev, void *data,
 int i915_enable_vblank(struct drm_device *dev, int pipe)
 {
 	drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
-	u32	pipestat_reg = 0;
-	u32	pipestat;
-	u32	interrupt = 0;
 	unsigned long irqflags;
 
-	switch (pipe) {
-	case 0:
-		pipestat_reg = PIPEASTAT;
-		interrupt = I915_DISPLAY_PIPE_A_EVENT_INTERRUPT;
-		break;
-	case 1:
-		pipestat_reg = PIPEBSTAT;
-		interrupt = I915_DISPLAY_PIPE_B_EVENT_INTERRUPT;
-		break;
-	default:
-		DRM_ERROR("tried to enable vblank on non-existent pipe %d\n",
-			  pipe);
-		return 0;
-	}
-
 	spin_lock_irqsave(&dev_priv->user_irq_lock, irqflags);
-	/* Enabling vblank events in IMR comes before PIPESTAT write, or
-	 * there's a race where the PIPESTAT vblank bit gets set to 1, so
-	 * the OR of enabled PIPESTAT bits goes to 1, so the PIPExEVENT in
-	 * ISR flashes to 1, but the IIR bit doesn't get set to 1 because
-	 * IMR masks it.  It doesn't ever get set after we clear the masking
-	 * in IMR because the ISR bit is edge, not level-triggered, on the
-	 * OR of PIPESTAT bits.
-	 */
-	i915_enable_irq(dev_priv, interrupt);
-	pipestat = I915_READ(pipestat_reg);
 	if (IS_I965G(dev))
-		pipestat |= PIPE_START_VBLANK_INTERRUPT_ENABLE;
+		i915_enable_pipestat(dev_priv, pipe,
+				     PIPE_START_VBLANK_INTERRUPT_ENABLE);
 	else
-		pipestat |= PIPE_VBLANK_INTERRUPT_ENABLE;
-	/* Clear any stale interrupt status */
-	pipestat |= (PIPE_START_VBLANK_INTERRUPT_STATUS |
-		     PIPE_VBLANK_INTERRUPT_STATUS);
-	I915_WRITE(pipestat_reg, pipestat);
-	(void) I915_READ(pipestat_reg);	/* Posting read */
+		i915_enable_pipestat(dev_priv, pipe,
+				     PIPE_VBLANK_INTERRUPT_ENABLE);
 	spin_unlock_irqrestore(&dev_priv->user_irq_lock, irqflags);
-
 	return 0;
 }
 
@@ -625,37 +418,12 @@ int i915_enable_vblank(struct drm_device *dev, int pipe)
 void i915_disable_vblank(struct drm_device *dev, int pipe)
 {
 	drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
-	u32	pipestat_reg = 0;
-	u32	pipestat;
-	u32	interrupt = 0;
 	unsigned long irqflags;
 
-	switch (pipe) {
-	case 0:
-		pipestat_reg = PIPEASTAT;
-		interrupt = I915_DISPLAY_PIPE_A_EVENT_INTERRUPT;
-		break;
-	case 1:
-		pipestat_reg = PIPEBSTAT;
-		interrupt = I915_DISPLAY_PIPE_B_EVENT_INTERRUPT;
-		break;
-	default:
-		DRM_ERROR("tried to disable vblank on non-existent pipe %d\n",
-			  pipe);
-		return;
-		break;
-	}
-
 	spin_lock_irqsave(&dev_priv->user_irq_lock, irqflags);
-	i915_disable_irq(dev_priv, interrupt);
-	pipestat = I915_READ(pipestat_reg);
-	pipestat &= ~(PIPE_START_VBLANK_INTERRUPT_ENABLE |
-		      PIPE_VBLANK_INTERRUPT_ENABLE);
-	/* Clear any stale interrupt status */
-	pipestat |= (PIPE_START_VBLANK_INTERRUPT_STATUS |
-		     PIPE_VBLANK_INTERRUPT_STATUS);
-	I915_WRITE(pipestat_reg, pipestat);
-	(void) I915_READ(pipestat_reg);	/* Posting read */
+	i915_disable_pipestat(dev_priv, pipe,
+			      PIPE_VBLANK_INTERRUPT_ENABLE |
+			      PIPE_START_VBLANK_INTERRUPT_ENABLE);
 	spin_unlock_irqrestore(&dev_priv->user_irq_lock, irqflags);
 }
 
@@ -696,123 +464,21 @@ int i915_vblank_pipe_get(struct drm_device *dev, void *data,
 int i915_vblank_swap(struct drm_device *dev, void *data,
 		     struct drm_file *file_priv)
 {
-	drm_i915_private_t *dev_priv = dev->dev_private;
-	drm_i915_vblank_swap_t *swap = data;
-	drm_i915_vbl_swap_t *vbl_swap, *vbl_old;
-	unsigned int pipe, seqtype, curseq;
-	unsigned long irqflags;
-	struct list_head *list;
-	int ret;
-
-	if (!dev_priv || !dev_priv->sarea_priv) {
-		DRM_ERROR("%s called with no initialization\n", __func__);
-		return -EINVAL;
-	}
-
-	if (dev_priv->sarea_priv->rotation) {
-		DRM_DEBUG("Rotation not supported\n");
-		return -EINVAL;
-	}
-
-	if (swap->seqtype & ~(_DRM_VBLANK_RELATIVE | _DRM_VBLANK_ABSOLUTE |
-			     _DRM_VBLANK_SECONDARY | _DRM_VBLANK_NEXTONMISS)) {
-		DRM_ERROR("Invalid sequence type 0x%x\n", swap->seqtype);
-		return -EINVAL;
-	}
-
-	pipe = (swap->seqtype & _DRM_VBLANK_SECONDARY) ? 1 : 0;
-
-	seqtype = swap->seqtype & (_DRM_VBLANK_RELATIVE | _DRM_VBLANK_ABSOLUTE);
-
-	if (!(dev_priv->vblank_pipe & (1 << pipe))) {
-		DRM_ERROR("Invalid pipe %d\n", pipe);
-		return -EINVAL;
-	}
-
-	spin_lock_irqsave(&dev->drw_lock, irqflags);
-
-	if (!drm_get_drawable_info(dev, swap->drawable)) {
-		spin_unlock_irqrestore(&dev->drw_lock, irqflags);
-		DRM_DEBUG("Invalid drawable ID %d\n", swap->drawable);
-		return -EINVAL;
-	}
-
-	spin_unlock_irqrestore(&dev->drw_lock, irqflags);
-
-	/*
-	 * We take the ref here and put it when the swap actually completes
-	 * in the tasklet.
+	/* The delayed swap mechanism was fundamentally racy, and has been
+	 * removed.  The model was that the client requested a delayed flip/swap
+	 * from the kernel, then waited for vblank before continuing to perform
+	 * rendering.  The problem was that the kernel might wake the client
+	 * up before it dispatched the vblank swap (since the lock has to be
+	 * held while touching the ringbuffer), in which case the client would
+	 * clear and start the next frame before the swap occurred, and
+	 * flicker would occur in addition to likely missing the vblank.
+	 *
+	 * In the absence of this ioctl, userland falls back to a correct path
+	 * of waiting for a vblank, then dispatching the swap on its own.
+	 * Context switching to userland and back is plenty fast enough for
+	 * meeting the requirements of vblank swapping.
 	 */
-	ret = drm_vblank_get(dev, pipe);
-	if (ret)
-		return ret;
-	curseq = drm_vblank_count(dev, pipe);
-
-	if (seqtype == _DRM_VBLANK_RELATIVE)
-		swap->sequence += curseq;
-
-	if ((curseq - swap->sequence) <= (1<<23)) {
-		if (swap->seqtype & _DRM_VBLANK_NEXTONMISS) {
-			swap->sequence = curseq + 1;
-		} else {
-			DRM_DEBUG("Missed target sequence\n");
-			drm_vblank_put(dev, pipe);
-			return -EINVAL;
-		}
-	}
-
-	vbl_swap = drm_calloc(1, sizeof(*vbl_swap), DRM_MEM_DRIVER);
-
-	if (!vbl_swap) {
-		DRM_ERROR("Failed to allocate memory to queue swap\n");
-		drm_vblank_put(dev, pipe);
-		return -ENOMEM;
-	}
-
-	vbl_swap->drw_id = swap->drawable;
-	vbl_swap->pipe = pipe;
-	vbl_swap->sequence = swap->sequence;
-
-	spin_lock_irqsave(&dev_priv->swaps_lock, irqflags);
-
-	list_for_each(list, &dev_priv->vbl_swaps.head) {
-		vbl_old = list_entry(list, drm_i915_vbl_swap_t, head);
-
-		if (vbl_old->drw_id == swap->drawable &&
-		    vbl_old->pipe == pipe &&
-		    vbl_old->sequence == swap->sequence) {
-			spin_unlock_irqrestore(&dev_priv->swaps_lock, irqflags);
-			drm_vblank_put(dev, pipe);
-			drm_free(vbl_swap, sizeof(*vbl_swap), DRM_MEM_DRIVER);
-			DRM_DEBUG("Already scheduled\n");
-			return 0;
-		}
-	}
-
-	if (dev_priv->swaps_pending >= 10) {
-		DRM_DEBUG("Too many swaps queued\n");
-		DRM_DEBUG(" pipe 0: %d pipe 1: %d\n",
-			  drm_vblank_count(dev, 0),
-			  drm_vblank_count(dev, 1));
-
-		list_for_each(list, &dev_priv->vbl_swaps.head) {
-			vbl_old = list_entry(list, drm_i915_vbl_swap_t, head);
-			DRM_DEBUG("\tdrw %x pipe %d seq %x\n",
-				  vbl_old->drw_id, vbl_old->pipe,
-				  vbl_old->sequence);
-		}
-		spin_unlock_irqrestore(&dev_priv->swaps_lock, irqflags);
-		drm_vblank_put(dev, pipe);
-		drm_free(vbl_swap, sizeof(*vbl_swap), DRM_MEM_DRIVER);
-		return -EBUSY;
-	}
-
-	list_add_tail(&vbl_swap->head, &dev_priv->vbl_swaps.head);
-	dev_priv->swaps_pending++;
-
-	spin_unlock_irqrestore(&dev_priv->swaps_lock, irqflags);
-
-	return 0;
+	return -EINVAL;
 }
 
 /* drm_dma.h hooks
@@ -822,37 +488,35 @@ void i915_driver_irq_preinstall(struct drm_device * dev)
 	drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
 
 	I915_WRITE(HWSTAM, 0xeffe);
+	I915_WRITE(PIPEASTAT, 0);
+	I915_WRITE(PIPEBSTAT, 0);
 	I915_WRITE(IMR, 0xffffffff);
 	I915_WRITE(IER, 0x0);
+	(void) I915_READ(IER);
 }
 
 int i915_driver_irq_postinstall(struct drm_device *dev)
 {
 	drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
-	int ret, num_pipes = 2;
-
-	spin_lock_init(&dev_priv->swaps_lock);
-	INIT_LIST_HEAD(&dev_priv->vbl_swaps.head);
-	INIT_WORK(&dev_priv->vblank_work, i915_vblank_work_handler);
-	dev_priv->swaps_pending = 0;
-
-	/* Set initial unmasked IRQs to just the selected vblank pipes. */
-	dev_priv->irq_mask_reg = ~0;
-
-	ret = drm_vblank_init(dev, num_pipes);
-	if (ret)
-		return ret;
 
 	dev_priv->vblank_pipe = DRM_I915_VBLANK_PIPE_A | DRM_I915_VBLANK_PIPE_B;
-	dev_priv->irq_mask_reg &= ~I915_DISPLAY_PIPE_A_VBLANK_INTERRUPT;
-	dev_priv->irq_mask_reg &= ~I915_DISPLAY_PIPE_B_VBLANK_INTERRUPT;
 
 	dev->max_vblank_count = 0xffffff; /* only 24 bits of frame count */
 
-	dev_priv->irq_mask_reg &= I915_INTERRUPT_ENABLE_MASK;
+	/* Unmask the interrupts that we always want on. */
+	dev_priv->irq_mask_reg = ~I915_INTERRUPT_ENABLE_FIX;
+
+	dev_priv->pipestat[0] = 0;
+	dev_priv->pipestat[1] = 0;
+
+	/* Disable pipe interrupt enables, clear pending pipe status */
+	I915_WRITE(PIPEASTAT, I915_READ(PIPEASTAT) & 0x8000ffff);
+	I915_WRITE(PIPEBSTAT, I915_READ(PIPEBSTAT) & 0x8000ffff);
+	/* Clear pending interrupt status */
+	I915_WRITE(IIR, I915_READ(IIR));
 
-	I915_WRITE(IMR, dev_priv->irq_mask_reg);
 	I915_WRITE(IER, I915_INTERRUPT_ENABLE_MASK);
+	I915_WRITE(IMR, dev_priv->irq_mask_reg);
 	(void) I915_READ(IER);
 
 	opregion_enable_asle(dev);
@@ -864,7 +528,6 @@ int i915_driver_irq_postinstall(struct drm_device *dev)
 void i915_driver_irq_uninstall(struct drm_device * dev)
 {
 	drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
-	u32 temp;
 
 	if (!dev_priv)
 		return;
@@ -872,13 +535,12 @@ void i915_driver_irq_uninstall(struct drm_device * dev)
 	dev_priv->vblank_pipe = 0;
 
 	I915_WRITE(HWSTAM, 0xffffffff);
+	I915_WRITE(PIPEASTAT, 0);
+	I915_WRITE(PIPEBSTAT, 0);
 	I915_WRITE(IMR, 0xffffffff);
 	I915_WRITE(IER, 0x0);
 
-	temp = I915_READ(PIPEASTAT);
-	I915_WRITE(PIPEASTAT, temp);
-	temp = I915_READ(PIPEBSTAT);
-	I915_WRITE(PIPEBSTAT, temp);
-	temp = I915_READ(IIR);
-	I915_WRITE(IIR, temp);
+	I915_WRITE(PIPEASTAT, I915_READ(PIPEASTAT) & 0x8000ffff);
+	I915_WRITE(PIPEBSTAT, I915_READ(PIPEBSTAT) & 0x8000ffff);
+	I915_WRITE(IIR, I915_READ(IIR));
 }