Make inteldrm_intr only do any work if we know for sure that interrupts

are unmasked (so we aren't vt switched).

Delay mutex aquisition until after we've make sure we have to worry
about interrupts.

The ironlake version of this behaves funny for guenther@ with
interaction on docking then restarting X. so has been left out of this
commit until I work out what the hell is going on.

Joint work with deraadt@ been in snaps for weeks

1 files changed, 10 insertions, 8 deletions

diff --git a/sys/dev/pci/drm/i915_drv.c b/sys/dev/pci/drm/i915_drv.c
index 6fb20fed36a..cb8d7069df4 100644
--- a/sys/dev/pci/drm/i915_drv.c
+++ b/sys/dev/pci/drm/i915_drv.c
@@ -711,20 +711,22 @@ inteldrm_intr(void *arg)
 	struct drm_device	*dev = (struct drm_device *)dev_priv->drmdev;
 	u_int32_t		 iir, pipea_stats = 0, pipeb_stats = 0;
 
-	/* we're not set up, don't poke the hw */
-	if (dev_priv->hw_status_page == NULL)
-		return (0);
 	/*
-	 * lock is to protect from writes to PIPESTAT and IMR from other cores.
+	 * we're not set up, don't poke the hw  and if we're vt switched
+	 * then nothing will be enabled
 	 */
-	mtx_enter(&dev_priv->user_irq_lock);
+	if (dev_priv->hw_status_page == NULL || dev_priv->mm.suspended)
+		return (0);
+
 	iir = I915_READ(IIR);
-	if (iir == 0) {
-		mtx_leave(&dev_priv->user_irq_lock);
+	if (iir == 0)
 		return (0);
-	}
 
 	/*
+	 * lock is to protect from writes to PIPESTAT and IMR from other cores.
+	 */
+	mtx_enter(&dev_priv->user_irq_lock);
+	/*
 	 * Clear the PIPE(A|B)STAT regs before the IIR
 	 */
 	if (iir & I915_DISPLAY_PIPE_A_EVENT_INTERRUPT) {