From 0389cdeed90a87624cd775c058369395a7c4c259 Mon Sep 17 00:00:00 2001
From: Duncan Ma <duncanma@amd.com>
Date: Tue, 8 Feb 2022 15:05:09 -0500
Subject: drm/amd/display: Set compbuf size to min at prep prevent overbook crb
Git-commit: b51178d6edddbfc8cb4da5b5e9c924f2d24bbcac
Patch-mainline: v5.18-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]
Detbuffer size is dynamically set for dcn31x. At certain moment,
compbuf+(def size * num pipes) > config return buffer size causing
flickering. This is easily reproducible when MPO is
enabled with two displays.

[How]
At prepare BW, use the min comp buffer size. When it is to
optimize BW, set compbuf size back to maximum possible size.

Reviewed-by: Charlene Liu <Charlene.Liu@amd.com>
Acked-by: Qingqing Zhuo <qingqing.zhuo@amd.com>
Signed-off-by: Duncan Ma <duncanma@amd.com>
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
 drivers/gpu/drm/amd/display/dc/dcn315/dcn315_resource.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/amd/display/dc/dcn315/dcn315_resource.c b/drivers/gpu/drm/amd/display/dc/dcn315/dcn315_resource.c
index f22158bb4b13..46b170e60a54 100644
--- a/drivers/gpu/drm/amd/display/dc/dcn315/dcn315_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn315/dcn315_resource.c
@@ -147,6 +147,7 @@ struct _vcs_dpi_ip_params_st dcn3_15_ip = {
 	.hostvm_max_page_table_levels = 2,
 	.rob_buffer_size_kbytes = 64,
 	.det_buffer_size_kbytes = DCN3_15_DEFAULT_DET_SIZE,
+	.min_comp_buffer_size_kbytes = DCN3_15_MIN_COMPBUF_SIZE_KB,
 	.config_return_buffer_size_in_kbytes = 1024,
 	.compressed_buffer_segment_size_in_kbytes = 64,
 	.meta_fifo_size_in_kentries = 32,
-- 
2.38.1