drm/i915: Drop the extra GEN8_PCU_IIR posting read from cherryview_irq_preinstall()

Looks like a leftover POSTING_READ(GEN8_PCU_IIR) in
cherryview_irq_preinstall() from some earlier age. GEN5_IRQ_RESET()
already does the posting read so this changes nothing, so kill it.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@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 1ec4ebbb89f3b7a449980988c5312e2332eaec69..1e4062d0961667ad444046c52df9e321fa2bf11c 100644 (file)
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -3188,8 +3188,6 @@ static void cherryview_irq_preinstall(struct drm_device *dev)
 
        GEN5_IRQ_RESET(GEN8_PCU_);
 
-       POSTING_READ(GEN8_PCU_IIR);
-
        I915_WRITE(DPINVGTT, DPINVGTT_STATUS_MASK_CHV);
 
        I915_WRITE(PORT_HOTPLUG_EN, 0);