[Intel-gfx] [PATCH] Revert "Revert "drm/i915/dp: Correctly advertise HBR3 for GEN11+""

[Imre Deak]

The problem the reverted patch revealed could've been fixed by commit
619ad4874585 ("drm/i915/ddi: Don't frob the DP link scramble disabling flag")
in particular because the revealed problem (at least in one case) happened
when switching to the TPS4 training pattern, which needs scrambling.

Let's try applying the HBR3 fix again.

This reverts commit d3913019602e32ef6fbba8eb0167e83250cdab22.

Cc: Matt Atwood <matthew.s.atwood at intel.com>
Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
Cc: Manasi Navare <manasi.d.navare at intel.com>
Cc: José Roberto de Souza <jose.souza at intel.com>
Signed-off-by: Imre Deak <imre.deak at intel.com>
---
 drivers/gpu/drm/i915/display/intel_dp.c | 28 ++++++++++---------------
 1 file changed, 11 insertions(+), 17 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index d6295eb20b63..a5ab405d3a12 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -137,6 +137,8 @@ static const u8 valid_dsc_slicecount[] = {1, 2, 4};
  *
  * If a CPU or PCH DP output is attached to an eDP panel, this function
  * will return true, and false otherwise.
+ *
+ * This function is not safe to use prior to encoder type being set.
  */
 bool intel_dp_is_edp(struct intel_dp *intel_dp)
 {
@@ -8157,8 +8159,6 @@ intel_dp_init_connector(struct intel_digital_port *dig_port,
 		     intel_encoder->base.name))
 		return false;
 
-	intel_dp_set_source_rates(intel_dp);
-
 	intel_dp->reset_link_params = true;
 	intel_dp->pps_pipe = INVALID_PIPE;
 	intel_dp->active_pipe = INVALID_PIPE;
@@ -8174,28 +8174,22 @@ intel_dp_init_connector(struct intel_digital_port *dig_port,
 		 */
 		drm_WARN_ON(dev, intel_phy_is_tc(dev_priv, phy));
 		type = DRM_MODE_CONNECTOR_eDP;
+		intel_encoder->type = INTEL_OUTPUT_EDP;
+
+		/* eDP only on port B and/or C on vlv/chv */
+		if (drm_WARN_ON(dev, (IS_VALLEYVIEW(dev_priv) ||
+				      IS_CHERRYVIEW(dev_priv)) &&
+				port != PORT_B && port != PORT_C))
+			return false;
 	} else {
 		type = DRM_MODE_CONNECTOR_DisplayPort;
 	}
 
+	intel_dp_set_source_rates(intel_dp);
+
 	if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv))
 		intel_dp->active_pipe = vlv_active_pipe(intel_dp);
 
-	/*
-	 * For eDP we always set the encoder type to INTEL_OUTPUT_EDP, but
-	 * for DP the encoder type can be set by the caller to
-	 * INTEL_OUTPUT_UNKNOWN for DDI, so don't rewrite it.
-	 */
-	if (type == DRM_MODE_CONNECTOR_eDP)
-		intel_encoder->type = INTEL_OUTPUT_EDP;
-
-	/* eDP only on port B and/or C on vlv/chv */
-	if (drm_WARN_ON(dev, (IS_VALLEYVIEW(dev_priv) ||
-			      IS_CHERRYVIEW(dev_priv)) &&
-			intel_dp_is_edp(intel_dp) &&
-			port != PORT_B && port != PORT_C))
-		return false;
-
 	drm_dbg_kms(&dev_priv->drm,
 		    "Adding %s connector on [ENCODER:%d:%s]\n",
 		    type == DRM_MODE_CONNECTOR_eDP ? "eDP" : "DP",
-- 
2.23.1