[PATCH 3/4] drm/i915/ptl/dp_mst: Align slave transcoder sequences with spec wrt. DP2 config

[Imre Deak]

On PTL during modeset enabling and disabling enable and disable the DP2
configuration for MST slave transcoders as required by the specification.

The spec requires the same programming steps on ADLP+ platforms as well,
this will be addressed by the next patch.

Bspec: 68849
Signed-off-by: Imre Deak <imre.deak at intel.com>
---
 drivers/gpu/drm/i915/display/intel_dp_mst.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c b/drivers/gpu/drm/i915/display/intel_dp_mst.c
index 7c16406883594..b1eee8500a383 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_mst.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c
@@ -1057,6 +1057,9 @@ static void intel_mst_post_disable_dp(struct intel_atomic_state *state,
 
 	intel_ddi_disable_transcoder_func(old_crtc_state);
 
+	if (DISPLAY_VER(dev_priv) >= 30 && !last_mst_stream)
+		intel_ddi_config_transcoder_dp2(encoder, old_crtc_state, false);
+
 	for_each_pipe_crtc_modeset_disable(display, pipe_crtc, old_crtc_state, i) {
 		const struct intel_crtc_state *old_pipe_crtc_state =
 			intel_atomic_get_old_crtc_state(state, pipe_crtc);
@@ -1224,8 +1227,10 @@ static void intel_mst_pre_enable_dp(struct intel_atomic_state *state,
 	if (DISPLAY_VER(dev_priv) < 12 || !first_mst_stream)
 		intel_ddi_enable_transcoder_clock(encoder, pipe_config);
 
-	if (DISPLAY_VER(dev_priv) >= 30 && !first_mst_stream)
+	if (DISPLAY_VER(dev_priv) >= 30 && !first_mst_stream) {
+		intel_ddi_config_transcoder_dp2(encoder, pipe_config, true);
 		intel_ddi_config_transcoder_func(encoder, pipe_config);
+	}
 
 	intel_dsc_dp_pps_write(&dig_port->base, pipe_config);
 	intel_ddi_set_dp_msa(pipe_config, conn_state);
-- 
2.44.2