drm/i915: Assert that HSW/BDW LCPLL is using the non-SSC reference
authorVille Syrjälä <ville.syrjala@linux.intel.com>
Tue, 4 Jun 2019 20:09:32 +0000 (23:09 +0300)
committerVille Syrjälä <ville.syrjala@linux.intel.com>
Wed, 12 Jun 2019 11:49:47 +0000 (14:49 +0300)
Only the non-SSC reference is truly supported for the LCPLL. Assert
that it is indeed selected.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190604200933.29417-4-ville.syrjala@linux.intel.com
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
drivers/gpu/drm/i915/intel_display_power.c

index 278a7edc94f5bf41c4d02d53bc1a0a4b3d63fbb8..bb9ef1cea5dba48e367761c86dd0ae7d86c292c2 100644 (file)
@@ -3665,6 +3665,9 @@ static void hsw_assert_cdclk(struct drm_i915_private *dev_priv)
 
        if (val & LCPLL_PLL_DISABLE)
                DRM_ERROR("LCPLL is disabled\n");
+
+       if ((val & LCPLL_REF_MASK) != LCPLL_REF_NON_SSC)
+               DRM_ERROR("LCPLL not using non-SSC reference\n");
 }
 
 static void assert_can_disable_lcpll(struct drm_i915_private *dev_priv)