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path: root/drivers/gpu/drm/i915/i915_irq.c
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Diffstat (limited to 'drivers/gpu/drm/i915/i915_irq.c')
-rw-r--r--drivers/gpu/drm/i915/i915_irq.c293
1 files changed, 153 insertions, 140 deletions
diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index 82752d6..69b9a42 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
@@ -121,80 +168,102 @@ 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);
-
- return IRQ_HANDLED;
+ return ret;
}
static int i915_emit_irq(struct drm_device * dev)
@@ -330,48 +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;
}
@@ -381,37 +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);
}
@@ -476,32 +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;
-
- /* 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);
@@ -513,7 +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;
@@ -521,13 +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));
}
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