drm/amd/display: Skip to enable dsc if it has been off

[WHY]
It makes DSC enable when we commit the stream which need
keep power off, and then it will skip to disable DSC if
pipe reset at this situation as power has been off. It may
cause the DSC unexpected enable on the pipe with the
next new stream which doesn't support DSC.

[HOW]
Check the DSC used on current pipe status when update stream.
Skip to enable if it has been off. The operation enable
DSC should happen when set power on.

Cc: Mario Limonciello <mario.limonciello@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Reviewed-by: Wenjing Liu <wenjing.liu@amd.com>
Signed-off-by: Zhikai Zhai <zhikai.zhai@amd.com>
Signed-off-by: Alex Hung <alex.hung@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

Author: Zhikai Zhai

drivers/gpu/drm/amd/display/dc/hwss/dcn32/dcn32_hwseq.c

@@ -1032,6 +1032,20 @@ void dcn32_update_dsc_on_stream(struct pipe_ctx *pipe_ctx, bool enable)
 		struct dsc_config dsc_cfg;
 		struct dsc_optc_config dsc_optc_cfg = {0};
 		enum optc_dsc_mode optc_dsc_mode;
+		struct dcn_dsc_state dsc_state = {0};
+
+		if (!dsc) {
+			DC_LOG_DSC("DSC is NULL for tg instance %d:", pipe_ctx->stream_res.tg->inst);
+			return;
+		}
+
+		if (dsc->funcs->dsc_read_state) {
+			dsc->funcs->dsc_read_state(dsc, &dsc_state);
+			if (!dsc_state.dsc_fw_en) {
+				DC_LOG_DSC("DSC has been disabled for tg instance %d:", pipe_ctx->stream_res.tg->inst);
+				return;
+			}
+		}
 
 		/* Enable DSC hw block */
 		dsc_cfg.pic_width = (stream->timing.h_addressable + stream->timing.h_border_left + stream->timing.h_border_right) / opp_cnt;

drivers/gpu/drm/amd/display/dc/hwss/dcn35/dcn35_hwseq.c

@@ -334,7 +334,20 @@ static void update_dsc_on_stream(struct pipe_ctx *pipe_ctx, bool enable)
 		struct dsc_config dsc_cfg;
 		struct dsc_optc_config dsc_optc_cfg = {0};
 		enum optc_dsc_mode optc_dsc_mode;
+		struct dcn_dsc_state dsc_state = {0};
 
+		if (!dsc) {
+			DC_LOG_DSC("DSC is NULL for tg instance %d:", pipe_ctx->stream_res.tg->inst);
+			return;
+		}
+
+		if (dsc->funcs->dsc_read_state) {
+			dsc->funcs->dsc_read_state(dsc, &dsc_state);
+			if (!dsc_state.dsc_fw_en) {
+				DC_LOG_DSC("DSC has been disabled for tg instance %d:", pipe_ctx->stream_res.tg->inst);
+				return;
+			}
+		}
 		/* Enable DSC hw block */
 		dsc_cfg.pic_width = (stream->timing.h_addressable + stream->timing.h_border_left + stream->timing.h_border_right) / opp_cnt;
 		dsc_cfg.pic_height = stream->timing.v_addressable + stream->timing.v_border_top + stream->timing.v_border_bottom;