I915_WRITE(GEN6_RC_CONTROL, rc6_mode);
 
        val = vlv_punit_read(dev_priv, PUNIT_REG_GPU_FREQ_STS);
-       switch ((val >> 6) & 3) {
-       case 0:
-       case 1:
-               dev_priv->mem_freq = 800;
-               break;
-       case 2:
-               dev_priv->mem_freq = 1066;
-               break;
-       case 3:
-               dev_priv->mem_freq = 1333;
-               break;
-       }
-       DRM_DEBUG_DRIVER("DDR speed: %d MHz", dev_priv->mem_freq);
 
        DRM_DEBUG_DRIVER("GPLL enabled? %s\n", val & 0x10 ? "yes" : "no");
        DRM_DEBUG_DRIVER("GPU status: 0x%08x\n", val);
 static void valleyview_init_clock_gating(struct drm_device *dev)
 {
        struct drm_i915_private *dev_priv = dev->dev_private;
+       u32 val;
+
+       mutex_lock(&dev_priv->rps.hw_lock);
+       val = vlv_punit_read(dev_priv, PUNIT_REG_GPU_FREQ_STS);
+       mutex_unlock(&dev_priv->rps.hw_lock);
+       switch ((val >> 6) & 3) {
+       case 0:
+       case 1:
+               dev_priv->mem_freq = 800;
+               break;
+       case 2:
+               dev_priv->mem_freq = 1066;
+               break;
+       case 3:
+               dev_priv->mem_freq = 1333;
+               break;
+       }
+       DRM_DEBUG_DRIVER("DDR speed: %d MHz", dev_priv->mem_freq);
 
        I915_WRITE(DSPCLK_GATE_D, VRHUNIT_CLOCK_GATE_DISABLE);