drm/amd/display: properly configure DCFCLK when enable/disable Freesync

[Why]
Bandwidth validation is using Freesync parameters
from previous Freesync state.
Bandwidth validation ignores DCFCLK calculated
after Freesync parameters are configured

[How]
Set Freesync bandwidth parameters to its default
state before running bandwidth validation.
Take DCFCLK calculated after Freesync bandwidth
parameters are assigned and bandwidth is
recalculated.
Tested-by: NDaniel Wheeler <daniel.wheeler@amd.com>
Reviewed-by: NMartin Leung <Martin.Leung@amd.com>
Reviewed-by: NNevenko Stupar <Nevenko.Stupar@amd.com>
Reviewed-by: NJun Lei <Jun.Lei@amd.com>
Acked-by: NQingqing Zhuo <qingqing.zhuo@amd.com>
Signed-off-by: NVladimir Stempen <vladimir.stempen@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/dcn32/dcn32_resource.c

@@ -1805,6 +1805,13 @@ bool dcn32_validate_bandwidth(struct dc *dc,
 	int pipe_cnt = 0;
 	display_e2e_pipe_params_st *pipes = kzalloc(dc->res_pool->pipe_count * sizeof(display_e2e_pipe_params_st), GFP_KERNEL);
 	struct mall_temp_config mall_temp_config;
+
+	/* To handle Freesync properly, setting FreeSync DML parameters
+	 * to its default state for the first stage of validation
+	 */
+	context->bw_ctx.bw.dcn.clk.fw_based_mclk_switching = false;
+	context->bw_ctx.dml.soc.dram_clock_change_requirement_final = true;
+
 	DC_LOGGER_INIT(dc->ctx->logger);
 
 	/* For fast validation, there are situations where a shallow copy of

drivers/gpu/drm/amd/display/dc/dml/dcn32/dcn32_fpu.c

@@ -1769,6 +1769,7 @@ void dcn32_calculate_wm_and_dlg_fpu(struct dc *dc, struct dc_state *context,
 	int i, pipe_idx, vlevel_temp = 0;
 	double dcfclk = dcn3_2_soc.clock_limits[0].dcfclk_mhz;
 	double dcfclk_from_validation = context->bw_ctx.dml.vba.DCFCLKState[vlevel][context->bw_ctx.dml.vba.maxMpcComb];
+	double dcfclk_from_fw_based_mclk_switching = dcfclk_from_validation;
 	bool pstate_en = context->bw_ctx.dml.vba.DRAMClockChangeSupport[vlevel][context->bw_ctx.dml.vba.maxMpcComb] !=
 			dm_dram_clock_change_unsupported;
 	unsigned int dummy_latency_index = 0;
@@ -1804,7 +1805,7 @@ void dcn32_calculate_wm_and_dlg_fpu(struct dc *dc, struct dc_state *context,
 					dc->clk_mgr->bw_params->wm_table.nv_entries[WM_A].dml_input.pstate_latency_us;
 			dcn32_internal_validate_bw(dc, context, pipes, &pipe_cnt, &vlevel, false);
 			maxMpcComb = context->bw_ctx.dml.vba.maxMpcComb;
-			dcfclk = context->bw_ctx.dml.vba.DCFCLKState[vlevel][context->bw_ctx.dml.vba.maxMpcComb];
+			dcfclk_from_fw_based_mclk_switching = context->bw_ctx.dml.vba.DCFCLKState[vlevel][context->bw_ctx.dml.vba.maxMpcComb];
 			pstate_en = context->bw_ctx.dml.vba.DRAMClockChangeSupport[vlevel][maxMpcComb] !=
 					dm_dram_clock_change_unsupported;
 		}
@@ -1890,6 +1891,10 @@ void dcn32_calculate_wm_and_dlg_fpu(struct dc *dc, struct dc_state *context,
 	pipes[0].clks_cfg.dcfclk_mhz = dcfclk_from_validation;
 	pipes[0].clks_cfg.socclk_mhz = context->bw_ctx.dml.soc.clock_limits[vlevel].socclk_mhz;
 
+	if (context->bw_ctx.bw.dcn.clk.fw_based_mclk_switching) {
+		pipes[0].clks_cfg.dcfclk_mhz = dcfclk_from_fw_based_mclk_switching;
+	}
+
 	if (dc->clk_mgr->bw_params->wm_table.nv_entries[WM_C].valid) {
 		min_dram_speed_mts = context->bw_ctx.dml.vba.DRAMSpeed;
 		min_dram_speed_mts_margin = 160;