[137/146] drm/i915: fix user irq miss in BSD ring on g4x

From: Greg KH
Date: Wed Jun 01 2011 - 04:56:47 EST


2.6.38-stable review patch. If anyone has any objections, please let us know.

------------------

From: Boqun Feng <boqun.feng@xxxxxxxxx>

commit 5bfa1063a775836a84f97e4df863fc36e1f856ad upstream.

On g4x, user interrupt in BSD ring is missed.
This is because though g4x and ironlake share the same bsd_ring,
their interrupt control interfaces have _two_ differences.

1.different irq enable/disable functions:
On g4x are i915_enable_irq and i915_disable_irq.
On ironlake are ironlake_enable_irq and ironlake_disable_irq.
2.different irq flag:
On g4x user interrupt flag in BSD ring on is I915_BSD_USER_INTERRUPT.
On ironlake is GT_BSD_USER_INTERRUPT

Old bsd_ring_get/put_irq call ring_get_irq and ring_get_irq.
ring_get_irq and ring_put_irq only call ironlake_enable/disable_irq.
So comes the irq miss on g4x.

To fix this, as other rings' code do, conditionally call different
functions(i915_enable/disable_irq and ironlake_enable/disable_irq)
and use different interrupt flags in bsd_ring_get/put_irq.

Signed-off-by: Boqun Feng <boqun.feng@xxxxxxxxx>
Reviewed-by: Xiang, Haihao <haihao.xiang@xxxxxxxxx>
Signed-off-by: Keith Packard <keithp@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>

---
drivers/gpu/drm/i915/intel_ringbuffer.c | 29 +++++++++++++++++++++++++++--
1 file changed, 27 insertions(+), 2 deletions(-)

--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -684,12 +684,37 @@ gen6_ring_put_irq(struct intel_ring_buff
static bool
bsd_ring_get_irq(struct intel_ring_buffer *ring)
{
- return ring_get_irq(ring, GT_BSD_USER_INTERRUPT);
+ struct drm_device *dev = ring->dev;
+ drm_i915_private_t *dev_priv = dev->dev_private;
+
+ if (!dev->irq_enabled)
+ return false;
+
+ spin_lock(&ring->irq_lock);
+ if (ring->irq_refcount++ == 0) {
+ if (IS_G4X(dev))
+ i915_enable_irq(dev_priv, I915_BSD_USER_INTERRUPT);
+ else
+ ironlake_enable_irq(dev_priv, GT_BSD_USER_INTERRUPT);
+ }
+ spin_unlock(&ring->irq_lock);
+
+ return true;
}
static void
bsd_ring_put_irq(struct intel_ring_buffer *ring)
{
- ring_put_irq(ring, GT_BSD_USER_INTERRUPT);
+ struct drm_device *dev = ring->dev;
+ drm_i915_private_t *dev_priv = dev->dev_private;
+
+ spin_lock(&ring->irq_lock);
+ if (--ring->irq_refcount == 0) {
+ if (IS_G4X(dev))
+ i915_disable_irq(dev_priv, I915_BSD_USER_INTERRUPT);
+ else
+ ironlake_disable_irq(dev_priv, GT_BSD_USER_INTERRUPT);
+ }
+ spin_unlock(&ring->irq_lock);
}

static int


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