drm/amd/display: check actual clock value.

[Why]
Actual dpp/disp clock PMFW set are always equal or more than requested.
Need to cache the actual clock for debugging purpose.

[How]
Add actuall dpp/disp clk in clock manager and save it when set clocks.
Add an ASSERT in case of actual clock less than requested.
Signed-off-by: Yongqiang Sun <yongqiang.sun@amd.com>
Acked-by: Bindu Ramamurthy <bindu.r@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/clk_mgr/dcn21/rn_clk_mgr.c

@@ -170,7 +170,7 @@ void rn_update_clocks(struct clk_mgr *clk_mgr_base,
 
 	if (should_set_clock(safe_to_lower, new_clocks->dispclk_khz, clk_mgr_base->clks.dispclk_khz)) {
 		clk_mgr_base->clks.dispclk_khz = new_clocks->dispclk_khz;
-		rn_vbios_smu_set_dispclk(clk_mgr, clk_mgr_base->clks.dispclk_khz);
+		clk_mgr_base->clks.actual_dispclk_khz = rn_vbios_smu_set_dispclk(clk_mgr, clk_mgr_base->clks.dispclk_khz);
 
 		update_dispclk = true;
 	}
@@ -178,10 +178,13 @@ void rn_update_clocks(struct clk_mgr *clk_mgr_base,
 	if (dpp_clock_lowered) {
 		// increase per DPP DTO before lowering global dppclk
 		dcn20_update_clocks_update_dpp_dto(clk_mgr, context, safe_to_lower);
+		clk_mgr_base->clks.actual_dppclk_khz =
 				rn_vbios_smu_set_dppclk(clk_mgr, clk_mgr_base->clks.dppclk_khz);
+
 	} else {
 		// increase global DPPCLK before lowering per DPP DTO
 		if (update_dppclk || update_dispclk)
+			clk_mgr_base->clks.actual_dppclk_khz =
 					rn_vbios_smu_set_dppclk(clk_mgr, clk_mgr_base->clks.dppclk_khz);
 		// always update dtos unless clock is lowered and not safe to lower
 		if (new_clocks->dppclk_khz >= dc->current_state->bw_ctx.bw.dcn.clk.dppclk_khz)

drivers/gpu/drm/amd/display/dc/clk_mgr/dcn21/rn_clk_mgr_vbios_smu.c

@@ -136,6 +136,10 @@ int rn_vbios_smu_set_dispclk(struct clk_mgr_internal *clk_mgr, int requested_dis
 		}
 	}
 
+	// pmfw always set clock more than or equal requested clock
+	if (!IS_DIAG_DC(dc->ctx->dce_environment))
+		ASSERT(actual_dispclk_set_mhz >= requested_dispclk_khz / 1000);
+
 	return actual_dispclk_set_mhz * 1000;
 }
 
@@ -194,12 +198,16 @@ void rn_vbios_smu_set_phyclk(struct clk_mgr_internal *clk_mgr, int requested_phy
 int rn_vbios_smu_set_dppclk(struct clk_mgr_internal *clk_mgr, int requested_dpp_khz)
 {
 	int actual_dppclk_set_mhz = -1;
+	struct dc *dc = clk_mgr->base.ctx->dc;
 
 	actual_dppclk_set_mhz = rn_vbios_smu_send_msg_with_param(
 			clk_mgr,
 			VBIOSSMC_MSG_SetDppclkFreq,
 			requested_dpp_khz / 1000);
 
+	if (!IS_DIAG_DC(dc->ctx->dce_environment))
+		ASSERT(actual_dppclk_set_mhz >= requested_dpp_khz / 1000);
+
 	return actual_dppclk_set_mhz * 1000;
 }
 

drivers/gpu/drm/amd/display/dc/dc.h

@@ -342,7 +342,9 @@ enum dcn_pwr_state {
  */
 struct dc_clocks {
 	int dispclk_khz;
+	int actual_dispclk_khz;
 	int dppclk_khz;
+	int actual_dppclk_khz;
 	int disp_dpp_voltage_level_khz;
 	int dcfclk_khz;
 	int socclk_khz;