From: George Shen <george.shen@amd.com>
Date: Fri, 7 Oct 2022 16:43:26 +0000 (-0400)
Subject: drm/amd/display: Fix DCN32 DSC delay calculation
X-Git-Tag: v6.6.17~5843^2~24^2~25
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=86975c34b6e2ce85b5b03f3b0a83333c97890ad7;p=platform%2Fkernel%2Flinux-rpi.git

drm/amd/display: Fix DCN32 DSC delay calculation

[Why]
DCN32 DSC delay calculation had an unintentional integer division,
resulting in a mismatch against the DML spreadsheet.

[How]
Cast numerator to double before performing the division.

Reviewed-by: Alvin Lee <Alvin.Lee2@amd.com>
Acked-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: George Shen <george.shen@amd.com>
Tested-by: Mark Broadworth <mark.broadworth@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
---

diff --git a/drivers/gpu/drm/amd/display/dc/dml/dcn32/display_mode_vba_util_32.c b/drivers/gpu/drm/amd/display/dc/dml/dcn32/display_mode_vba_util_32.c
index ad66e24..4a3e7a5 100644
--- a/drivers/gpu/drm/amd/display/dc/dml/dcn32/display_mode_vba_util_32.c
+++ b/drivers/gpu/drm/amd/display/dc/dml/dcn32/display_mode_vba_util_32.c
@@ -1746,7 +1746,7 @@ unsigned int dml32_DSCDelayRequirement(bool DSCEnabled,
 		}
 
 		DSCDelayRequirement_val = DSCDelayRequirement_val + (HTotal - HActive) *
-				dml_ceil(DSCDelayRequirement_val / HActive, 1);
+				dml_ceil((double)DSCDelayRequirement_val / HActive, 1);
 
 		DSCDelayRequirement_val = DSCDelayRequirement_val * PixelClock / PixelClockBackEnd;