[Intel-gfx] [PATCH 3/4] drm/i915: Align vswing sequences with old ddi buffer registers.

[Rodrigo Vivi]

Vswing sequences on BXT and CNL are equivalent
to the ddi buffer registers setting on other platforms.

For some reason it got aligned with skl_ddi_set_iboost what
is semantically incorrect. This forced us to keep skipping
ddi buffer translation tables on the platforms that has
the vswing sequences.

v2: Don't mess with DP signal levels on this patch.

Cc: Vandana Kannan <vandana.kannan at intel.com>
Cc: Imre Deak <imre.deak at intel.com>
Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
Cc: Ander Conselvan de Oliveira <conselvan2 at gmail.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi at intel.com>
---
 drivers/gpu/drm/i915/intel_ddi.c | 22 ++++++++++------------
 1 file changed, 10 insertions(+), 12 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_ddi.c b/drivers/gpu/drm/i915/intel_ddi.c
index 9891ad40d1dc..a6056bb4f801 100644
--- a/drivers/gpu/drm/i915/intel_ddi.c
+++ b/drivers/gpu/drm/i915/intel_ddi.c
@@ -688,9 +688,6 @@ static void intel_prepare_dp_ddi_buffers(struct intel_encoder *encoder)
 	enum port port = intel_ddi_get_encoder_port(encoder);
 	const struct ddi_buf_trans *ddi_translations;
 
-	if (IS_GEN9_LP(dev_priv))
-		return;
-
 	switch (encoder->type) {
 	case INTEL_OUTPUT_EDP:
 		ddi_translations = intel_ddi_get_buf_trans_edp(dev_priv,
@@ -741,9 +738,6 @@ static void intel_prepare_hdmi_ddi_buffers(struct intel_encoder *encoder)
 	enum port port = intel_ddi_get_encoder_port(encoder);
 	const struct ddi_buf_trans *ddi_translations_hdmi;
 
-	if (IS_GEN9_LP(dev_priv))
-		return;
-
 	hdmi_level = intel_ddi_hdmi_level(dev_priv, port);
 
 	if (IS_GEN9_BC(dev_priv)) {
@@ -2151,7 +2145,9 @@ static void intel_ddi_pre_enable_dp(struct intel_encoder *encoder,
 
 	intel_display_power_get(dev_priv, dig_port->ddi_io_power_domain);
 
-	intel_prepare_dp_ddi_buffers(encoder);
+	if (!IS_GEN9_LP(dev_priv) && !IS_CANNONLAKE(dev_priv))
+		intel_prepare_dp_ddi_buffers(encoder);
+
 	intel_ddi_init_dp_buf_reg(encoder);
 	intel_dp_sink_dpms(intel_dp, DRM_MODE_DPMS_ON);
 	intel_dp_start_link_train(intel_dp);
@@ -2177,14 +2173,16 @@ static void intel_ddi_pre_enable_hdmi(struct intel_encoder *encoder,
 
 	intel_display_power_get(dev_priv, dig_port->ddi_io_power_domain);
 
-	intel_prepare_hdmi_ddi_buffers(encoder);
-	if (IS_GEN9_BC(dev_priv))
-		skl_ddi_set_iboost(encoder, level);
+	if (IS_CANNONLAKE(dev_priv))
+		cnl_ddi_vswing_sequence(encoder, level);
 	else if (IS_GEN9_LP(dev_priv))
 		bxt_ddi_vswing_sequence(dev_priv, level, port,
 					INTEL_OUTPUT_HDMI);
-	else if (IS_CANNONLAKE(dev_priv))
-		cnl_ddi_vswing_sequence(encoder, level);
+	else
+		intel_prepare_hdmi_ddi_buffers(encoder);
+
+	if (IS_GEN9_BC(dev_priv))
+		skl_ddi_set_iboost(encoder, level);
 
 	intel_hdmi->set_infoframes(drm_encoder,
 				   has_hdmi_sink,
-- 
2.13.2