From: Yihan Zhu <Yihan.Zhu@amd.com>
Date: Tue, 27 May 2025 20:47:40 +0000 (-0400)
Subject: drm/amd/display: Fix RMCM programming seq errors
X-Git-Tag: v6.16-rc3~23^2~2^2~14
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=158f9944ac05dafd2d3a23d0688e6cf40ef68b90;p=thirdparty%2Fkernel%2Fstable.git

drm/amd/display: Fix RMCM programming seq errors

[WHY & HOW]
Fix RMCM programming sequence errors and mapping issues to pass the RMCM
test.

Cc: Mario Limonciello <mario.limonciello@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Dmytro Laktyushkin <dmytro.laktyushkin@amd.com>
Signed-off-by: Yihan Zhu <Yihan.Zhu@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>
(cherry picked from commit 11baa4975025033547f45f5894087a0dda6efbb8)
Cc: stable@vger.kernel.org
---

diff --git a/drivers/gpu/drm/amd/display/dc/dml2/dml21/src/dml2_core/dml2_core_dcn4_calcs.c b/drivers/gpu/drm/amd/display/dc/dml2/dml21/src/dml2_core/dml2_core_dcn4_calcs.c
index c4dad7164d314..5b62cd19d9796 100644
--- a/drivers/gpu/drm/amd/display/dc/dml2/dml21/src/dml2_core/dml2_core_dcn4_calcs.c
+++ b/drivers/gpu/drm/amd/display/dc/dml2/dml21/src/dml2_core/dml2_core_dcn4_calcs.c
@@ -4685,7 +4685,10 @@ static void calculate_tdlut_setting(
 	//the tdlut is fetched during the 2 row times of prefetch.
 	if (p->setup_for_tdlut) {
 		*p->tdlut_groups_per_2row_ub = (unsigned int)math_ceil2((double) *p->tdlut_bytes_per_frame / *p->tdlut_bytes_per_group, 1);
-		*p->tdlut_opt_time = (*p->tdlut_bytes_per_frame - p->cursor_buffer_size * 1024) / tdlut_drain_rate;
+		if (*p->tdlut_bytes_per_frame > p->cursor_buffer_size * 1024)
+			*p->tdlut_opt_time = (*p->tdlut_bytes_per_frame - p->cursor_buffer_size * 1024) / tdlut_drain_rate;
+		else
+			*p->tdlut_opt_time = 0;
 		*p->tdlut_drain_time = p->cursor_buffer_size * 1024 / tdlut_drain_rate;
 		*p->tdlut_bytes_to_deliver = (unsigned int) (p->cursor_buffer_size * 1024.0);
 	}