From 1ef1a3c20ff1a6155d1a26357c7537e58d2d2285 Mon Sep 17 00:00:00 2001
From: George Shen <george.shen@amd.com>
Date: Thu, 16 Sep 2021 19:55:39 -0400
Subject: drm/amd/display: Handle Y carry-over in VCP X.Y calculation
Git-commit: 3626a6aebe62ce7067cdc460c0c644e9445386bb
Patch-mainline: v5.16-rc1
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/How]
Theoretically rare corner case where ceil(Y) results in rounding
up to an integer. If this happens, the 1 should be carried over to
the X value.
Reviewed-by: Wenjing Liu <wenjing.liu@amd.com>
Acked-by: Anson Jacob <Anson.Jacob@amd.com>
Signed-off-by: George Shen <george.shen@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/dcn10/dcn10_stream_encoder.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_stream_encoder.c b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_stream_encoder.c
index 687c3c6881a9..b0c08ee6bc2c 100644
--- a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_stream_encoder.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_stream_encoder.c
@@ -647,6 +647,12 @@ void enc1_stream_encoder_set_throttled_vcp_size(
x),
26));
+ // If y rounds up to integer, carry it over to x.
+ if (y >> 26) {
+ x += 1;
+ y = 0;
+ }
+
REG_SET_2(DP_MSE_RATE_CNTL, 0,
DP_MSE_RATE_X, x,
DP_MSE_RATE_Y, y);
--
2.38.1