From d2f0427f7380a077cf701c45f78abfe414e71a79 Mon Sep 17 00:00:00 2001
From: Sung Lee <sung.lee@amd.com>
Date: Tue, 4 Feb 2020 15:49:54 -0500
Subject: drm/amd/display: DCN2.x Do not program DPPCLK if same value
Git-commit: 8fab6a2faa1eb388b5eaf1ead4394f380a6403be
Patch-mainline: v5.6-rc2
References: jsc#SLE-12680, jsc#SLE-12880, jsc#SLE-12882, jsc#SLE-12883, jsc#SLE-13496, jsc#SLE-15322
[WHY]
Programming DPPCLK to the same value currently set may cause
underflow while playing video in certain conditions.
[HOW]
Only program DPPCLK if clock is not the same as the
previous value programmed.
Signed-off-by: Sung Lee <sung.lee@amd.com>
Reviewed-by: Yongqiang Sun <yongqiang.sun@amd.com>
Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Patrik Jakobsson <pjakobsson@suse.de>
---
drivers/gpu/drm/amd/display/dc/clk_mgr/dcn20/dcn20_clk_mgr.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn20/dcn20_clk_mgr.c b/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn20/dcn20_clk_mgr.c
index 495f01e9f2ca..49ce46b543ea 100644
--- a/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn20/dcn20_clk_mgr.c
+++ b/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn20/dcn20_clk_mgr.c
@@ -117,7 +117,7 @@ void dcn20_update_clocks_update_dpp_dto(struct clk_mgr_internal *clk_mgr,
prev_dppclk_khz = clk_mgr->base.ctx->dc->current_state->res_ctx.pipe_ctx[i].plane_res.bw.dppclk_khz;
- if (safe_to_lower || prev_dppclk_khz < dppclk_khz) {
+ if ((prev_dppclk_khz > dppclk_khz && safe_to_lower) || prev_dppclk_khz < dppclk_khz) {
clk_mgr->dccg->funcs->update_dpp_dto(
clk_mgr->dccg, dpp_inst, dppclk_khz);
}
--
2.28.0