drm/amd/display: Add function to get the pipe from the stream context

[Why]
We need a helper function in dc to grab the pipe from the stream
context.

[How]
Add it.
Reviewed-by: Martin Leung <Martin.Leung@amd.com>
Acked-by: Agustin Gutierrez <agustin.gutierrez@amd.com>
Signed-off-by: Leo (Hanghong) Ma <hanghong.ma@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

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

@@ -718,6 +718,20 @@ enum dc_status dc_stream_add_dsc_to_resource(struct dc *dc,
 	}
 }
 
+struct pipe_ctx *dc_stream_get_pipe_ctx(struct dc_stream_state *stream)
+{
+	int i = 0;
+
+	for (i = 0; i < MAX_PIPES; i++) {
+		struct pipe_ctx *pipe = &stream->ctx->dc->current_state->res_ctx.pipe_ctx[i];
+
+		if (pipe->stream == stream)
+			return pipe;
+	}
+
+	return NULL;
+}
+
 void dc_stream_log(const struct dc *dc, const struct dc_stream_state *stream)
 {
 	DC_LOG_DC(

drivers/gpu/drm/amd/display/dc/dc_stream.h

@@ -524,4 +524,6 @@ bool dc_stream_get_crtc_position(struct dc *dc,
 				 unsigned int *v_pos,
 				 unsigned int *nom_v_pos);
 
+struct pipe_ctx *dc_stream_get_pipe_ctx(struct dc_stream_state *stream);
+
 #endif /* DC_STREAM_H_ */