[PATCH] Revert "drm/amd/display: Program OTG vtotal min/max selectors unconditionally for DCN1+"

[Guilherme G. Piccoli]

This reverts commit 06c3a652a787efc960af7c8816036d25c4227c6c.

After this commit, the Steam Deck cannot boot with graphics anymore;
the following message is observed on dmesg:

"[drm] ERROR [CRTC:67:crtc-0] flip_done timed out"

No other error is observed, it just stays like that. After bisecting
amd-staging-drm-next, we narrowed it down to this commit. Seems it
makes sense to revert it to have the tree bootable until a proper
solution is worked.

Cc: Aurabindo Pillai <aurabindo.pillai at amd.com>
Cc: André Almeida <andrealmeid at igalia.com>
Cc: Melissa Wen <mwen at igalia.com>
Cc: Rodrigo Siqueira <Rodrigo.Siqueira at amd.com>
Signed-off-by: Guilherme G. Piccoli <gpiccoli at igalia.com>

---

Hi Alex / Aurabindo, we couldn't boot the Deck with in HEAD
(amd-staging-drm-next), git bisect led to this commit. Since its
description already mentions a potential proper solution, related
to the DMCUB (and some complex state tracking), I thought it was
more effective to revert it to allow booting the tree in Deck (and
maybe other HW - I just tested the Deck BTW).
Lemme know your thoughts.

Special thanks to André and Melissa for helping the debug / bisect!
We're open to test alternative patches, feel free to ping.
Cheers,

Guilherme


 drivers/gpu/drm/amd/display/dc/dcn10/dcn10_optc.c | 15 ++++++++++++---
 drivers/gpu/drm/amd/display/dc/dcn20/dcn20_optc.c | 10 ----------
 2 files changed, 12 insertions(+), 13 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_optc.c b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_optc.c
index 0e8f4f36c87c..27419cd98264 100644
--- a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_optc.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_optc.c
@@ -945,10 +945,19 @@ void optc1_set_drr(
 				OTG_FORCE_LOCK_ON_EVENT, 0,
 				OTG_SET_V_TOTAL_MIN_MASK_EN, 0,
 				OTG_SET_V_TOTAL_MIN_MASK, 0);
-	}
 
-	// Setup manual flow control for EOF via TRIG_A
-	optc->funcs->setup_manual_trigger(optc);
+		// Setup manual flow control for EOF via TRIG_A
+		optc->funcs->setup_manual_trigger(optc);
+
+	} else {
+		REG_UPDATE_4(OTG_V_TOTAL_CONTROL,
+				OTG_SET_V_TOTAL_MIN_MASK, 0,
+				OTG_V_TOTAL_MIN_SEL, 0,
+				OTG_V_TOTAL_MAX_SEL, 0,
+				OTG_FORCE_LOCK_ON_EVENT, 0);
+
+		optc->funcs->set_vtotal_min_max(optc, 0, 0);
+	}
 }
 
 void optc1_set_vtotal_min_max(struct timing_generator *optc, int vtotal_min, int vtotal_max)
diff --git a/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_optc.c b/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_optc.c
index 58bdbd859bf9..d6f095b4555d 100644
--- a/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_optc.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_optc.c
@@ -462,16 +462,6 @@ void optc2_setup_manual_trigger(struct timing_generator *optc)
 {
 	struct optc *optc1 = DCN10TG_FROM_TG(optc);
 
-	/* Set the min/max selectors unconditionally so that
-	 * DMCUB fw may change OTG timings when necessary
-	 * TODO: Remove the w/a after fixing the issue in DMCUB firmware
-	 */
-	REG_UPDATE_4(OTG_V_TOTAL_CONTROL,
-				 OTG_V_TOTAL_MIN_SEL, 1,
-				 OTG_V_TOTAL_MAX_SEL, 1,
-				 OTG_FORCE_LOCK_ON_EVENT, 0,
-				 OTG_SET_V_TOTAL_MIN_MASK, (1 << 1)); /* TRIGA */
-
 	REG_SET_8(OTG_TRIGA_CNTL, 0,
 			OTG_TRIGA_SOURCE_SELECT, 21,
 			OTG_TRIGA_SOURCE_PIPE_SELECT, optc->inst,
-- 
2.40.1