diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index a5cddcd6d3e0773026d148128214cf9435977dd0..ca9278be49f7d5f9f259d44ad6566c9a7c18d1ae 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -14740,6 +14740,24 @@ void intel_modeset_init(struct drm_device *dev) if (INTEL_INFO(dev)->num_pipes == 0) return; + /* + * There may be no VBT; and if the BIOS enabled SSC we can + * just keep using it to avoid unnecessary flicker. Whereas if the + * BIOS isn't using it, don't assume it will work even if the VBT + * indicates as much. + */ + if (HAS_PCH_IBX(dev) || HAS_PCH_CPT(dev)) { + bool bios_lvds_use_ssc = !!(I915_READ(PCH_DREF_CONTROL) & + DREF_SSC1_ENABLE); + + if (dev_priv->vbt.lvds_use_ssc != bios_lvds_use_ssc) { + DRM_DEBUG_KMS("SSC %sabled by BIOS, overriding VBT which says %sabled\n", + bios_lvds_use_ssc ? "en" : "dis", + dev_priv->vbt.lvds_use_ssc ? "en" : "dis"); + dev_priv->vbt.lvds_use_ssc = bios_lvds_use_ssc; + } + } + intel_init_display(dev); intel_init_audio(dev); @@ -15299,7 +15317,6 @@ void intel_display_resume(struct drm_device *dev) void intel_modeset_gem_init(struct drm_device *dev) { - struct drm_i915_private *dev_priv = dev->dev_private; struct drm_crtc *c; struct drm_i915_gem_object *obj; int ret; @@ -15308,16 +15325,6 @@ void intel_modeset_gem_init(struct drm_device *dev) intel_init_gt_powersave(dev); mutex_unlock(&dev->struct_mutex); - /* - * There may be no VBT; and if the BIOS enabled SSC we can - * just keep using it to avoid unnecessary flicker. Whereas if the - * BIOS isn't using it, don't assume it will work even if the VBT - * indicates as much. - */ - if (HAS_PCH_IBX(dev) || HAS_PCH_CPT(dev)) - dev_priv->vbt.lvds_use_ssc = !!(I915_READ(PCH_DREF_CONTROL) & - DREF_SSC1_ENABLE); - intel_modeset_init_hw(dev); intel_setup_overlay(dev);