drm/amd/display: Limit dcn32 to 1950Mhz display clock

[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

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 1c612cc..fd03134 100644 (file)
--- 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))