drm/i915: POSTING_READ(DEIER) on ivybridge_irq_handler

We have this POSTING_READ inside ironlake_irq_handler. I suppose we
also want it on IVB because we want to stop the IRQ handler as soon as
possible at this point.

Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index 3ef8f23..597a3d5 100644 (file)
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -1305,6 +1305,7 @@ static irqreturn_t ivybridge_irq_handler(int irq, void *arg)
        /* disable master interrupt before clearing iir  */
        de_ier = I915_READ(DEIER);
        I915_WRITE(DEIER, de_ier & ~DE_MASTER_IRQ_CONTROL);
+       POSTING_READ(DEIER);
 
        /* Disable south interrupts. We'll only write to SDEIIR once, so further
         * interrupts will will be stored on its back queue, and then we'll be