drm/amd/display: Fix 4to1 MPC black screen with DPP RCO

[Why]
DPP Root clock optimization when combined with 4to1 MPC combine results
in the screen turning black.

This is because the DPPCLK is stopped during the middle of an
optimize_bandwidth sequence during commit_minimal_transition without
going through plane power down/power up.

[How]
The intent of a 0Hz DPP clock through update_clocks is to disable the
DTO. This differs from the behavior of stopping the DPPCLK entirely
(utilizing a 0Hz clock on some ASIC) so it's better to move this logic
to reside next to plane power up/power down where we gate the HUBP/DPP
DOMAIN.

The new  sequence should be:
Power down: PG enabled -> RCO on
Power up: RCO off -> PG disabled

Rename power_on_plane to power_on_plane_resources to reflect the
actual operation that's occurring.

Cc: stable@vger.kernel.org
Cc: Mario Limonciello <mario.limonciello@amd.com>
Reviewed-by: Jun Lei <Jun.Lei@amd.com>
Acked-by: Qingqing Zhuo <qingqing.zhuo@amd.com>
Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 10 insertions, 0 deletions

diff --git a/drivers/gpu/drm/amd/display/dc/dcn314/dcn314_hwseq.c b/drivers/gpu/drm/amd/display/dc/dcn314/dcn314_hwseq.c
index bcc03426fc3e..40c488b26901 100644
--- a/drivers/gpu/drm/amd/display/dc/dcn314/dcn314_hwseq.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn314/dcn314_hwseq.c
@@ -390,6 +390,16 @@ void dcn314_set_pixels_per_cycle(struct pipe_ctx *pipe_ctx)
 				pix_per_cycle);
 }
 
+void dcn314_dpp_root_clock_control(struct dce_hwseq *hws, unsigned int dpp_inst, bool clock_on)
+{
+	if (!hws->ctx->dc->debug.root_clock_optimization.bits.dpp)
+		return;
+
+	if (hws->ctx->dc->res_pool->dccg->funcs->dpp_root_clock_control)
+		hws->ctx->dc->res_pool->dccg->funcs->dpp_root_clock_control(
+			hws->ctx->dc->res_pool->dccg, dpp_inst, clock_on);
+}
+
 void dcn314_hubp_pg_control(struct dce_hwseq *hws, unsigned int hubp_inst, bool power_on)
 {
 	struct dc_context *ctx = hws->ctx;