[RFC, v3, 14/15] drm/i915/ddi: handle 128b/132b SST in intel_ddi_read_func_ctl()

[Imre Deak]

From: Jani Nikula <jani.nikula at intel.com>

We'll only ever get here in MST mode from MST stream encoders; the
primary encoder's ->get_config() won't be called when we've detected
it's MST.

Signed-off-by: Jani Nikula <jani.nikula at intel.com>
[hack: fix enhanced framing hw readout/set master transcoder] (Imre)
Signed-off-by: Imre Deak <imre.deak at intel.com>
---
 drivers/gpu/drm/i915/display/intel_ddi.c      | 34 ++++++++++++++++---
 drivers/gpu/drm/i915/display/intel_dp.c       |  8 +++--
 .../drm/i915/display/intel_dp_link_training.c |  5 ++-
 3 files changed, 39 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_ddi.c b/drivers/gpu/drm/i915/display/intel_ddi.c
index 21dba87350856..14d8eb5f02ff1 100644
--- a/drivers/gpu/drm/i915/display/intel_ddi.c
+++ b/drivers/gpu/drm/i915/display/intel_ddi.c
@@ -577,10 +577,18 @@ intel_ddi_transcoder_func_reg_val_get(struct intel_encoder *encoder,
 			temp |= TRANS_DDI_MST_TRANSPORT_SELECT(master);
 		}
 	} else {
-		if (intel_dp_is_uhbr(crtc_state))
+		if (intel_dp_is_uhbr(crtc_state)) {
+			enum transcoder master;
+
 			temp |= TRANS_DDI_MODE_SELECT_FDI_OR_128B132B;
-		else
+
+			master = crtc_state->mst_master_transcoder;
+			drm_WARN_ON(&dev_priv->drm,
+				    master == INVALID_TRANSCODER);
+			temp |= TRANS_DDI_MST_TRANSPORT_SELECT(master);
+		} else {
 			temp |= TRANS_DDI_MODE_SELECT_DP_SST;
+		}
 		temp |= DDI_PORT_WIDTH(crtc_state->lane_count);
 	}
 
@@ -678,7 +686,8 @@ void intel_ddi_disable_transcoder_func(const struct intel_crtc_state *crtc_state
 			 TRANS_DDI_PORT_SYNC_MASTER_SELECT_MASK);
 
 	if (DISPLAY_VER(dev_priv) >= 12) {
-		if (!intel_dp_mst_is_master_trans(crtc_state)) {
+		if (!intel_dp_mst_is_master_trans(crtc_state) ||
+		    intel_dp_is_uhbr(crtc_state)) {
 			ctl &= ~(TGL_TRANS_DDI_PORT_MASK |
 				 TRANS_DDI_MODE_SELECT_MASK);
 		}
@@ -4028,6 +4037,11 @@ static void intel_ddi_read_func_ctl_dp_sst(struct intel_encoder *encoder,
 	crtc_state->lane_count =
 		((ddi_func_ctl & DDI_PORT_WIDTH_MASK) >> DDI_PORT_WIDTH_SHIFT) + 1;
 
+	if (DISPLAY_VER(display) >= 12 &&
+	    (ddi_func_ctl & TRANS_DDI_MODE_SELECT_MASK) == TRANS_DDI_MODE_SELECT_FDI_OR_128B132B)
+		crtc_state->mst_master_transcoder =
+			REG_FIELD_GET(TRANS_DDI_MST_TRANSPORT_SELECT_MASK, ddi_func_ctl);
+
 	intel_cpu_transcoder_get_m1_n1(crtc, cpu_transcoder, &crtc_state->dp_m_n);
 	intel_cpu_transcoder_get_m2_n2(crtc, cpu_transcoder, &crtc_state->dp_m2_n2);
 
@@ -4122,9 +4136,19 @@ static void intel_ddi_read_func_ctl(struct intel_encoder *encoder,
 		intel_ddi_read_func_ctl_fdi(encoder, pipe_config, ddi_func_ctl);
 	} else if (ddi_mode == TRANS_DDI_MODE_SELECT_DP_SST) {
 		intel_ddi_read_func_ctl_dp_sst(encoder, pipe_config, ddi_func_ctl);
-	} else if (ddi_mode == TRANS_DDI_MODE_SELECT_DP_MST ||
-		   (ddi_mode == TRANS_DDI_MODE_SELECT_FDI_OR_128B132B && HAS_DP20(display))) {
+	} else if (ddi_mode == TRANS_DDI_MODE_SELECT_DP_MST) {
 		intel_ddi_read_func_ctl_dp_mst(encoder, pipe_config, ddi_func_ctl);
+	} else if (ddi_mode == TRANS_DDI_MODE_SELECT_FDI_OR_128B132B && HAS_DP20(display)) {
+		struct intel_dp *intel_dp = enc_to_intel_dp(encoder);
+
+		/*
+		 * If this is true, we know we're being called from mst stream
+		 * encoder's ->get_config().
+		 */
+		if (intel_dp->is_mst)
+			intel_ddi_read_func_ctl_dp_mst(encoder, pipe_config, ddi_func_ctl);
+		else
+			intel_ddi_read_func_ctl_dp_sst(encoder, pipe_config, ddi_func_ctl);
 	}
 }
 
diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index fba3af3382808..dc84979d32947 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -3148,8 +3148,12 @@ intel_dp_compute_config(struct intel_encoder *encoder,
 	pipe_config->limited_color_range =
 		intel_dp_limited_color_range(pipe_config, conn_state);
 
-	pipe_config->enhanced_framing =
-		drm_dp_enhanced_frame_cap(intel_dp->dpcd);
+	if (intel_dp_is_uhbr(pipe_config)) {
+		pipe_config->mst_master_transcoder = pipe_config->cpu_transcoder;
+	} else {
+		pipe_config->enhanced_framing =
+			drm_dp_enhanced_frame_cap(intel_dp->dpcd);
+	}
 
 	if (pipe_config->dsc.compression_enable)
 		link_bpp_x16 = pipe_config->dsc.compressed_bpp_x16;
diff --git a/drivers/gpu/drm/i915/display/intel_dp_link_training.c b/drivers/gpu/drm/i915/display/intel_dp_link_training.c
index fd4824398b8db..1e9744ef8e0ab 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_link_training.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_link_training.c
@@ -760,8 +760,11 @@ static void intel_dp_update_link_bw_set(struct intel_dp *intel_dp,
 					const struct intel_crtc_state *crtc_state,
 					u8 link_bw, u8 rate_select)
 {
+	bool enhanced_framing = crtc_state->enhanced_framing ||
+				intel_dp_is_uhbr(crtc_state);
+
 	intel_dp_link_training_set_bw(intel_dp, link_bw, rate_select, crtc_state->lane_count,
-				      crtc_state->enhanced_framing);
+				      enhanced_framing);
 }
 
 /*
-- 
2.44.2