drm/i915: Kill vlv_update_rps_cur_delay()

Polling to make sure the current GPU frequency matches the last
requested frequency should not be necessay, and if there's some
throttling involved, the two might not match anyway.

Since we're still seeing this trigger occasionally, and it just
introduces a rather pointless 10 ms delay, it seems like better
to kill it off.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/intel_pm.c

@@ -3584,31 +3584,6 @@ void gen6_rps_boost(struct drm_i915_private *dev_priv)
 	mutex_unlock(&dev_priv->rps.hw_lock);
 }
 
-/*
- * Wait until the previous freq change has completed,
- * or the timeout elapsed, and then update our notion
- * of the current GPU frequency.
- */
-static void vlv_update_rps_cur_delay(struct drm_i915_private *dev_priv)
-{
-	u32 pval;
-
-	WARN_ON(!mutex_is_locked(&dev_priv->rps.hw_lock));
-
-	if (wait_for(((pval = vlv_punit_read(dev_priv, PUNIT_REG_GPU_FREQ_STS)) & GENFREQSTATUS) == 0, 10))
-		DRM_DEBUG_DRIVER("timed out waiting for Punit\n");
-
-	pval >>= 8;
-
-	if (pval != dev_priv->rps.cur_delay)
-		DRM_DEBUG_DRIVER("Punit overrode GPU freq: %d MHz (%u) requested, but got %d Mhz (%u)\n",
-				 vlv_gpu_freq(dev_priv, dev_priv->rps.cur_delay),
-				 dev_priv->rps.cur_delay,
-				 vlv_gpu_freq(dev_priv, pval), pval);
-
-	dev_priv->rps.cur_delay = pval;
-}
-
 void valleyview_set_rps(struct drm_device *dev, u8 val)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
@@ -3617,8 +3592,6 @@ void valleyview_set_rps(struct drm_device *dev, u8 val)
 	WARN_ON(val > dev_priv->rps.max_delay);
 	WARN_ON(val < dev_priv->rps.min_delay);
 
-	vlv_update_rps_cur_delay(dev_priv);
-
 	DRM_DEBUG_DRIVER("GPU freq request from %d MHz (%u) to %d MHz (%u)\n",
 			 vlv_gpu_freq(dev_priv, dev_priv->rps.cur_delay),
 			 dev_priv->rps.cur_delay,