From c60a39c271fe5493e8547839cf25586607b2ad8c Mon Sep 17 00:00:00 2001
From: Jun Lei <jun.lei@amd.com>
Date: Thu, 20 Oct 2022 11:46:44 -0400
Subject: drm/amd/display: Limit dcn32 to 1950Mhz display clock
Git-commit: e59843c4cdd68a369591630088171eeacce9859f
Patch-mainline: v6.1-rc4
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 jsc#PED-2849

[why]
Hardware team recommends we limit dispclock to 1950Mhz for all DCN3.2.x

[how]
Limit to 1950 when initializing clocks.

Tested-by: Mark Broadworth <mark.broadworth@amd.com>
Reviewed-by: Alvin Lee <Alvin.Lee2@amd.com>
Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Jun Lei <jun.lei@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org # 6.0.x
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
 .../gpu/drm/amd/display/dc/clk_mgr/dcn32/dcn32_clk_mgr.c  | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn32/dcn32_clk_mgr.c b/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn32/dcn32_clk_mgr.c
index 1c612ccf1944..fd0313468fdb 100644
--- a/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn32/dcn32_clk_mgr.c
+++ b/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn32/dcn32_clk_mgr.c
@@ -157,6 +157,7 @@ void dcn32_init_clocks(struct clk_mgr *clk_mgr_base)
 	struct clk_mgr_internal *clk_mgr = TO_CLK_MGR_INTERNAL(clk_mgr_base);
 	unsigned int num_levels;
 	struct clk_limit_num_entries *num_entries_per_clk = &clk_mgr_base->bw_params->clk_table.num_entries_per_clk;
+	unsigned int i;
 
 	memset(&(clk_mgr_base->clks), 0, sizeof(struct dc_clocks));
 	clk_mgr_base->clks.p_state_change_support = true;
@@ -205,18 +206,17 @@ void dcn32_init_clocks(struct clk_mgr *clk_mgr_base)
 		clk_mgr->dpm_present = true;
 
 	if (clk_mgr_base->ctx->dc->debug.min_disp_clk_khz) {
-		unsigned int i;
-
 		for (i = 0; i < num_levels; i++)
 			if (clk_mgr_base->bw_params->clk_table.entries[i].dispclk_mhz
 					< khz_to_mhz_ceil(clk_mgr_base->ctx->dc->debug.min_disp_clk_khz))
 				clk_mgr_base->bw_params->clk_table.entries[i].dispclk_mhz
 					= khz_to_mhz_ceil(clk_mgr_base->ctx->dc->debug.min_disp_clk_khz);
 	}
+	for (i = 0; i < num_levels; i++)
+		if (clk_mgr_base->bw_params->clk_table.entries[i].dispclk_mhz > 1950)
+			clk_mgr_base->bw_params->clk_table.entries[i].dispclk_mhz = 1950;
 
 	if (clk_mgr_base->ctx->dc->debug.min_dpp_clk_khz) {
-		unsigned int i;
-
 		for (i = 0; i < num_levels; i++)
 			if (clk_mgr_base->bw_params->clk_table.entries[i].dppclk_mhz
 					< khz_to_mhz_ceil(clk_mgr_base->ctx->dc->debug.min_dpp_clk_khz))
-- 
2.38.1