diff options
| author | Chris Wilson <chris@chris-wilson.co.uk> | 2012-05-09 21:45:43 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-06-01 15:18:24 +0800 |
| commit | b019d4bf936fa7212341053f337c6714f29fc95e (patch) | |
| tree | 2d2eff17ade31ffea18a468d1aad361b2f81b4ea | |
| parent | 46f736c6f722e9a71ab552178a6bf4edf85ba371 (diff) | |
drm/i915: Avoid a double-read of PCH_IIR during interrupt handling
commit 9adab8b5a7fde248504f484e197589f3e3c922e2 upstream.
Currently the code re-reads PCH_IIR during the hotplug interrupt
processing. Not only is this a wasted read, but introduces a potential
for handling a spurious interrupt as we then may not clear all the
interrupts processed (since the re-read IIR may contains more interrupts
asserted than we clear using the result of the original read).
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/gpu/drm/i915/i915_irq.c | 9 |
1 files changed, 3 insertions, 6 deletions
diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c index afd4e03e337e..f57e5cfb162e 100644 --- a/drivers/gpu/drm/i915/i915_irq.c +++ b/drivers/gpu/drm/i915/i915_irq.c @@ -424,14 +424,11 @@ static void gen6_pm_rps_work(struct work_struct *work) mutex_unlock(&dev_priv->dev->struct_mutex); } -static void pch_irq_handler(struct drm_device *dev) +static void pch_irq_handler(struct drm_device *dev, u32 pch_iir) { drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private; - u32 pch_iir; int pipe; - pch_iir = I915_READ(SDEIIR); - if (pch_iir & SDE_AUDIO_POWER_MASK) DRM_DEBUG_DRIVER("PCH audio power change on port %d\n", (pch_iir & SDE_AUDIO_POWER_MASK) >> @@ -529,7 +526,7 @@ static irqreturn_t ivybridge_irq_handler(DRM_IRQ_ARGS) if (de_iir & DE_PCH_EVENT_IVB) { if (pch_iir & SDE_HOTPLUG_MASK_CPT) queue_work(dev_priv->wq, &dev_priv->hotplug_work); - pch_irq_handler(dev); + pch_irq_handler(dev, pch_iir); } if (pm_iir & GEN6_PM_DEFERRED_EVENTS) { @@ -629,7 +626,7 @@ static irqreturn_t ironlake_irq_handler(DRM_IRQ_ARGS) if (de_iir & DE_PCH_EVENT) { if (pch_iir & hotplug_mask) queue_work(dev_priv->wq, &dev_priv->hotplug_work); - pch_irq_handler(dev); + pch_irq_handler(dev, pch_iir); } if (de_iir & DE_PCU_EVENT) { |