Merge remote-tracking branch 'slave-dma/next'

[karo-tx-linux.git] / drivers / gpu / drm / i915 / intel_dp.c

diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 2c555f91bfae076688fe07e1694c75932a9c97d2..1a431377d83b76ad22bccf795db770ab3b40bd3e 100644 (file)
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -1401,6 +1401,26 @@ static void intel_dp_get_config(struct intel_encoder *encoder,
                else
                        pipe_config->port_clock = 270000;
        }
+
+       if (is_edp(intel_dp) && dev_priv->vbt.edp_bpp &&
+           pipe_config->pipe_bpp > dev_priv->vbt.edp_bpp) {
+               /*
+                * This is a big fat ugly hack.
+                *
+                * Some machines in UEFI boot mode provide us a VBT that has 18
+                * bpp and 1.62 GHz link bandwidth for eDP, which for reasons
+                * unknown we fail to light up. Yet the same BIOS boots up with
+                * 24 bpp and 2.7 GHz link. Use the same bpp as the BIOS uses as
+                * max, not what it tells us to use.
+                *
+                * Note: This will still be broken if the eDP panel is not lit
+                * up by the BIOS, and thus we can't get the mode at module
+                * load.
+                */
+               DRM_DEBUG_KMS("pipe has %d bpp for eDP panel, overriding BIOS-provided max %d bpp\n",
+                             pipe_config->pipe_bpp, dev_priv->vbt.edp_bpp);
+               dev_priv->vbt.edp_bpp = pipe_config->pipe_bpp;
+       }
 }
 
 static bool is_edp_psr(struct intel_dp *intel_dp)