drm/amd/display: Select correct DTO source

[WHY&HOW]
Change criteria for setting DTO source value, and always set it regardless of
the signal type.
Signed-off-by: Dillon Varone <dillon.varone@amd.com>
Acked-by: Aurabindo Pillai <aurabindo.pillai@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/dce/dce_clock_source.c

@@ -992,7 +992,18 @@ static bool dcn31_program_pix_clk(
 			REG_WRITE(PHASE[inst], pll_settings->actual_pix_clk_100hz * 100);
 			REG_WRITE(MODULO[inst], dp_dto_ref_khz * 1000);
 		}
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+		/* Enable DTO */
+		if (clk_src->cs_mask->PIPE0_DTO_SRC_SEL)
+			REG_UPDATE_2(PIXEL_RATE_CNTL[inst],
+					DP_DTO0_ENABLE, 1,
+					PIPE0_DTO_SRC_SEL, 1);
+		else
+			REG_UPDATE(PIXEL_RATE_CNTL[inst],
+					DP_DTO0_ENABLE, 1);
+#else
 		REG_UPDATE(PIXEL_RATE_CNTL[inst], DP_DTO0_ENABLE, 1);
+#endif
 	} else {
 		if (IS_FPGA_MAXIMUS_DC(clock_source->ctx->dce_environment)) {
 			unsigned int inst = pix_clk_params->controller_id - CONTROLLER_ID_D0;
@@ -1004,10 +1015,26 @@ static bool dcn31_program_pix_clk(
 			REG_WRITE(MODULO[inst], dp_dto_ref_100hz);
 
 			/* Enable DTO */
+	#if defined(CONFIG_DRM_AMD_DC_DCN)
+			if (clk_src->cs_mask->PIPE0_DTO_SRC_SEL)
+				REG_UPDATE_2(PIXEL_RATE_CNTL[inst],
+						DP_DTO0_ENABLE, 1,
+						PIPE0_DTO_SRC_SEL, 1);
+			else
+				REG_UPDATE(PIXEL_RATE_CNTL[inst],
+						DP_DTO0_ENABLE, 1);
+	#else
 			REG_UPDATE(PIXEL_RATE_CNTL[inst], DP_DTO0_ENABLE, 1);
+	#endif
 			return true;
 		}
 
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+		if (clk_src->cs_mask->PIPE0_DTO_SRC_SEL)
+			REG_UPDATE(PIXEL_RATE_CNTL[inst],
+					PIPE0_DTO_SRC_SEL, 0);
+#endif
+
 		/*ATOMBIOS expects pixel rate adjusted by deep color ratio)*/
 		bp_pc_params.controller_id = pix_clk_params->controller_id;
 		bp_pc_params.pll_id = clock_source->id;