drm/amd/display: Turn on phantom OTG before disabling phantom pipe

[Description]
- Proper phantom pipe disable sequence was missing in
  commit_planes_for_stream
- If disabling phantom pipe, turn on phantom OTG first, and turn
  off the phantom OTG after the plane is disabled
- Also update sequence for enabling / disabling phantom streams
  (apply_ctx_to_hw). When enabling phantom pipes, enable before
  doing front end programming for phantom pipes. If disabling
  phantom pipes, disable after front end programming (i.e. after
  phantom plane disable)
- TODO: Still need to properly handle transition case when a phantom
  pipe is transitioned directly into a real pipe (need to fully disable
  the phantom pipe first)

Acked-by: Aurabindo Pillai <aurabindo.pillai@amd.com>
Signed-off-by: Alvin Lee <Alvin.Lee2@amd.com>
Reviewed-by: Jun Lei <Jun.Lei@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 24 insertions, 0 deletions

diff --git a/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_hwseq.c b/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_hwseq.c
index 6291a241158a..366ba05cf8ef 100644
--- a/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_hwseq.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_hwseq.c
@@ -582,6 +582,9 @@ void dcn20_plane_atomic_disable(struct dc *dc, struct pipe_ctx *pipe_ctx)
 	if (pipe_ctx->stream_res.gsl_group != 0)
 		dcn20_setup_gsl_group_as_lock(dc, pipe_ctx, false);
 
+	if (hubp->funcs->hubp_update_mall_sel)
+		hubp->funcs->hubp_update_mall_sel(hubp, 0, false);
+
 	dc->hwss.set_flip_control_gsl(pipe_ctx, false);
 
 	hubp->funcs->hubp_clk_cntl(hubp, false);
@@ -605,6 +608,9 @@ void dcn20_plane_atomic_disable(struct dc *dc, struct pipe_ctx *pipe_ctx)
 
 void dcn20_disable_plane(struct dc *dc, struct pipe_ctx *pipe_ctx)
 {
+	bool is_phantom = pipe_ctx->plane_state && pipe_ctx->plane_state->is_phantom;
+	struct timing_generator *tg = is_phantom ? pipe_ctx->stream_res.tg : NULL;
+
 	DC_LOGGER_INIT(dc->ctx->logger);
 
 	if (!pipe_ctx->plane_res.hubp || pipe_ctx->plane_res.hubp->power_gated)
@@ -612,6 +618,12 @@ void dcn20_disable_plane(struct dc *dc, struct pipe_ctx *pipe_ctx)
 
 	dcn20_plane_atomic_disable(dc, pipe_ctx);
 
+	/* Turn back off the phantom OTG after the phantom plane is fully disabled
+	 */
+	if (is_phantom)
+		if (tg && tg->funcs->disable_phantom_crtc)
+			tg->funcs->disable_phantom_crtc(tg);
+
 	DC_LOG_DC("Power down front end %d\n",
 					pipe_ctx->pipe_idx);
 }
@@ -1803,6 +1815,18 @@ void dcn20_program_front_end_for_ctx(
 		dcn20_detect_pipe_changes(&dc->current_state->res_ctx.pipe_ctx[i],
 				&context->res_ctx.pipe_ctx[i]);
 
+	/* When disabling phantom pipes, turn on phantom OTG first (so we can get double
+	 * buffer updates properly)
+	 */
+	for (i = 0; i < dc->res_pool->pipe_count; i++)
+		if (context->res_ctx.pipe_ctx[i].update_flags.bits.disable
+				&& dc->current_state->res_ctx.pipe_ctx[i].stream->mall_stream_config.type == SUBVP_PHANTOM) {
+			struct timing_generator *tg = dc->current_state->res_ctx.pipe_ctx[i].stream_res.tg;
+
+			if (tg->funcs->enable_crtc)
+				tg->funcs->enable_crtc(tg);
+		}
+
 	/* OTG blank before disabling all front ends */
 	for (i = 0; i < dc->res_pool->pipe_count; i++)
 		if (context->res_ctx.pipe_ctx[i].update_flags.bits.disable