[PATCH 15/33] drm/amd/display: Limit dcn32 to 1950Mhz display clock

Rodrigo Siqueira Rodrigo.Siqueira at amd.com
Thu Oct 20 15:46:44 UTC 2022


From: Jun Lei <jun.lei at amd.com>

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

[how]
Limit to 1950 when initializing clocks.

Reviewed-by: Alvin Lee <Alvin.Lee2 at amd.com>
Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira at amd.com>
Signed-off-by: Jun Lei <jun.lei at amd.com>
---
 .../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))
-- 
2.35.1



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