diff options
-rw-r--r-- | drivers/gpu/drm/i915/i915_irq.c | 108 |
1 files changed, 61 insertions, 47 deletions
diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c index ca3ed18..654d42f 100644 --- a/drivers/gpu/drm/i915/i915_irq.c +++ b/drivers/gpu/drm/i915/i915_irq.c @@ -168,69 +168,83 @@ 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 pipea_stats = 0, pipeb_stats = 0; + u32 iir, new_iir; + u32 pipea_stats, pipeb_stats; int vblank = 0; unsigned long irqflags; - spin_lock_irqsave(&dev_priv->user_irq_lock, irqflags); 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); - } - spin_unlock_irqrestore(&dev_priv->user_irq_lock, irqflags); + if (iir == 0) return IRQ_NONE; - } - - /* - * Clear the PIPE(A|B)STAT regs before the IIR - */ - if (iir & I915_DISPLAY_PIPE_A_EVENT_INTERRUPT) { - pipea_stats = I915_READ(PIPEASTAT); - I915_WRITE(PIPEASTAT, pipea_stats); - } - if (iir & I915_DISPLAY_PIPE_B_EVENT_INTERRUPT) { - pipeb_stats = I915_READ(PIPEBSTAT); - I915_WRITE(PIPEBSTAT, pipeb_stats); - } + do { + pipea_stats = 0; + pipeb_stats = 0; + /* + * Clear the PIPE(A|B)STAT regs before the IIR + */ + if (iir & I915_DISPLAY_PIPE_A_EVENT_INTERRUPT) { + spin_lock_irqsave(&dev_priv->user_irq_lock, irqflags); + pipea_stats = I915_READ(PIPEASTAT); + I915_WRITE(PIPEASTAT, pipea_stats); + spin_unlock_irqrestore(&dev_priv->user_irq_lock, + irqflags); + } - 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 (iir & I915_DISPLAY_PIPE_B_EVENT_INTERRUPT) { + spin_lock_irqsave(&dev_priv->user_irq_lock, irqflags); + pipeb_stats = I915_READ(PIPEBSTAT); + I915_WRITE(PIPEBSTAT, pipeb_stats); + spin_unlock_irqrestore(&dev_priv->user_irq_lock, + irqflags); + } - spin_unlock_irqrestore(&dev_priv->user_irq_lock, irqflags); + 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 (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 (iir & I915_USER_INTERRUPT) { + dev_priv->mm.irq_gem_seqno = i915_get_gem_seqno(dev); + DRM_WAKEUP(&dev_priv->irq_queue); + } - if (pipea_stats & I915_VBLANK_INTERRUPT_STATUS) { - vblank++; - drm_handle_vblank(dev, 0); - } + if (pipea_stats & I915_VBLANK_INTERRUPT_STATUS) { + vblank++; + drm_handle_vblank(dev, 0); + } - if (pipeb_stats & I915_VBLANK_INTERRUPT_STATUS) { - vblank++; - drm_handle_vblank(dev, 1); - } + if (pipeb_stats & I915_VBLANK_INTERRUPT_STATUS) { + vblank++; + drm_handle_vblank(dev, 1); + } - if ((pipeb_stats & I915_LEGACY_BLC_EVENT_STATUS) || - (iir & I915_ASLE_INTERRUPT)) - opregion_asle_intr(dev); + if ((pipeb_stats & I915_LEGACY_BLC_EVENT_STATUS) || + (iir & I915_ASLE_INTERRUPT)) + opregion_asle_intr(dev); + + /* 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; + } while (iir != 0); return IRQ_HANDLED; } |