drm/i915: Check for driver readyness before handling an underrun interrupt

[people/ms/linux.git] / drivers / gpu / drm / i915 / intel_fifo_underrun.c

diff --git a/drivers/gpu/drm/i915/intel_fifo_underrun.c b/drivers/gpu/drm/i915/intel_fifo_underrun.c
index 77af512d2d3506db65df6cb555bdb5ff94d7249a..b16f2cd15cabb88c70c067d1f46cc01abd9b8c48 100644 (file)
--- a/drivers/gpu/drm/i915/intel_fifo_underrun.c
+++ b/drivers/gpu/drm/i915/intel_fifo_underrun.c
@@ -282,16 +282,6 @@ bool intel_set_cpu_fifo_underrun_reporting(struct drm_i915_private *dev_priv,
        return ret;
 }
 
-static bool
-__cpu_fifo_underrun_reporting_enabled(struct drm_i915_private *dev_priv,
-                                     enum pipe pipe)
-{
-       struct drm_crtc *crtc = dev_priv->pipe_to_crtc_mapping[pipe];
-       struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
-
-       return !intel_crtc->cpu_fifo_underrun_disabled;
-}
-
 /**
  * intel_set_pch_fifo_underrun_reporting - set PCH fifo underrun reporting state
  * @dev_priv: i915 device instance
@@ -352,9 +342,15 @@ bool intel_set_pch_fifo_underrun_reporting(struct drm_i915_private *dev_priv,
 void intel_cpu_fifo_underrun_irq_handler(struct drm_i915_private *dev_priv,
                                         enum pipe pipe)
 {
+       struct drm_crtc *crtc = dev_priv->pipe_to_crtc_mapping[pipe];
+
+       /* We may be called too early in init, thanks BIOS! */
+       if (crtc == NULL)
+               return;
+
        /* GMCH can't disable fifo underruns, filter them. */
        if (HAS_GMCH_DISPLAY(dev_priv->dev) &&
-           !__cpu_fifo_underrun_reporting_enabled(dev_priv, pipe))
+           to_intel_crtc(crtc)->cpu_fifo_underrun_disabled)
                return;
 
        if (intel_set_cpu_fifo_underrun_reporting(dev_priv, pipe, false))