From d60061e667c56f8cdde0715a8d7752be229c24f1 Mon Sep 17 00:00:00 2001
From: Chris Park <Chris.Park@amd.com>
Date: Tue, 15 Mar 2022 12:21:43 -0400
Subject: drm/amd/display: Correct Slice reset calculation
Git-commit: 862a876c3a6372f2fa9d0c6510f1976ac94fc857
Patch-mainline: v5.18-rc2
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225
[Why]
Once DSC slice cannot fit pixel clock, we incorrectly
reset min slices to 0 and allow max slice to operate,
even when max slice itself cannot fit the pixel clock
properly.
[How]
Change the sequence such that we correctly determine
DSC is not possible when both min slices and max
slices cannot fit pixel clock per slice.
Reviewed-by: Wenjing Liu <Wenjing.Liu@amd.com>
Acked-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: Chris Park <Chris.Park@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
drivers/gpu/drm/amd/display/dc/dsc/dc_dsc.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/amd/display/dc/dsc/dc_dsc.c b/drivers/gpu/drm/amd/display/dc/dsc/dc_dsc.c
index efc2339f1fa0..4385d19bc489 100644
--- a/drivers/gpu/drm/amd/display/dc/dsc/dc_dsc.c
+++ b/drivers/gpu/drm/amd/display/dc/dsc/dc_dsc.c
@@ -864,11 +864,11 @@ static bool setup_dsc_config(
min_slices_h = inc_num_slices(dsc_common_caps.slice_caps, min_slices_h);
}
+ is_dsc_possible = (min_slices_h <= max_slices_h);
+
if (pic_width % min_slices_h != 0)
min_slices_h = 0; // DSC TODO: Maybe try increasing the number of slices first?
- is_dsc_possible = (min_slices_h <= max_slices_h);
-
if (min_slices_h == 0 && max_slices_h == 0)
is_dsc_possible = false;
--
2.38.1