drm/amd/display: Remove connect DIG FE to its BE during timing programming

[why]
Causes regression with MST DSC displays not lighting up after DPMS

[how]
Revert commit 8cc426d7 ("drm/amd/display: Program DSC during timing programming")
Signed-off-by: Nikola Cornij <nikola.cornij@amd.com>
Reviewed-by: Aric Cyr <Aric.Cyr@amd.com>
Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/core/dc_link.c

@@ -3069,14 +3069,9 @@ void core_link_enable_stream(
 
 		if (pipe_ctx->stream->timing.flags.DSC) {
 			if (dc_is_dp_signal(pipe_ctx->stream->signal) ||
-					dc_is_virtual_signal(pipe_ctx->stream->signal)) {
-				/* Here we only need to enable DSC on RX. DSC HW programming
-				 * was done earlier, as part of timing programming.
-				 */
-				dp_set_dsc_on_rx(pipe_ctx, true);
-			}
+					dc_is_virtual_signal(pipe_ctx->stream->signal))
+				dp_set_dsc_enable(pipe_ctx, true);
 		}
-
 		dc->hwss.enable_stream(pipe_ctx);
 
 		/* Set DPS PPS SDP (AKA "info frames") */
@@ -3103,7 +3098,7 @@ void core_link_enable_stream(
 	} else { // if (IS_FPGA_MAXIMUS_DC(dc->ctx->dce_environment))
 		if (dc_is_dp_signal(pipe_ctx->stream->signal) ||
 				dc_is_virtual_signal(pipe_ctx->stream->signal))
-			dp_set_dsc_on_rx(pipe_ctx, true);
+			dp_set_dsc_enable(pipe_ctx, true);
 
 	}
 }

drivers/gpu/drm/amd/display/dc/core/dc_link_hwss.c

@@ -394,7 +394,7 @@ static void dsc_optc_config_log(struct display_stream_compressor *dsc,
 	DC_LOG_DSC("\tslice_width %d", config->slice_width);
 }
 
-bool dp_set_dsc_on_rx(struct pipe_ctx *pipe_ctx, bool enable)
+static bool dp_set_dsc_on_rx(struct pipe_ctx *pipe_ctx, bool enable)
 {
 	struct dc *dc = pipe_ctx->stream->ctx->dc;
 	struct dc_stream_state *stream = pipe_ctx->stream;

drivers/gpu/drm/amd/display/dc/dcn20/dcn20_hwseq.c

@@ -623,13 +623,6 @@ enum dc_status dcn20_enable_stream_timing(
 
 	/* TODO check if timing_changed, disable stream if timing changed */
 
-	/* Have to setup DSC here to make sure the bandwidth sent to DIG BE won't be bigger than
-	 * what the link and/or DIG BE can handle. VBID[6]/CompressedStream_flag will be automatically
-	 * set at a later time when the video is enabled (DP_VID_STREAM_EN = 1).
-	 */
-	if (pipe_ctx->stream->timing.flags.DSC)
-		dp_set_dsc_on_stream(pipe_ctx, true);
-
 	for (odm_pipe = pipe_ctx->next_odm_pipe; odm_pipe; odm_pipe = odm_pipe->next_odm_pipe) {
 		opp_inst[opp_cnt] = odm_pipe->stream_res.opp->inst;
 		opp_cnt++;

drivers/gpu/drm/amd/display/dc/inc/dc_link_dp.h

@@ -85,7 +85,6 @@ void dp_set_fec_enable(struct dc_link *link, bool enable);
 bool dp_set_dsc_enable(struct pipe_ctx *pipe_ctx, bool enable);
 bool dp_set_dsc_pps_sdp(struct pipe_ctx *pipe_ctx, bool enable);
 void dp_set_dsc_on_stream(struct pipe_ctx *pipe_ctx, bool enable);
-bool dp_set_dsc_on_rx(struct pipe_ctx *pipe_ctx, bool enable);
 bool dp_update_dsc_config(struct pipe_ctx *pipe_ctx);
 
 #endif /* __DC_LINK_DP_H__ */