[Intel-gfx] [PATCH] drm/i915: warn if Pineview CxSR can't be enabled

[Jesse Barnes]

If we don't detect a supported memory configuration, we can't enable
CxSR.  Warn the user in this case so they can file a bug.

Signed-off-by: Jesse Barnes <jbarnes at virtuousgeek.org>

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 33113c7..874f303 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -4527,6 +4527,11 @@ void intel_modeset_init(struct drm_device *dev)
 		    (unsigned long)dev);
 
 	intel_setup_overlay(dev);
+
+	if (IS_IGD(dev) && !intel_get_cxsr_latency(IS_IGDG(dev),
+						   dev_priv->fsb_freq,
+						   dev_priv->mem_freq))
+		DRM_ERROR("failed to find CxSR latency, disabling CxSR\n");
 }
 
 void intel_modeset_cleanup(struct drm_device *dev)