diff --git a/target/linux/rockchip/patches-5.4/809-arm64-dts-DoorNet1-add-dmc-and-dram-timing.patch b/target/linux/rockchip/patches-5.4/809-arm64-dts-DoorNet1-add-dmc-and-dram-timing.patch
new file mode 100644
index 000000000..031bb4a86
--- /dev/null
+++ b/target/linux/rockchip/patches-5.4/809-arm64-dts-DoorNet1-add-dmc-and-dram-timing.patch
@@ -0,0 +1,114 @@
+--- a/arch/arm64/boot/dts/rockchip/rk3328-doornet1.dts
++++ b/arch/arm64/boot/dts/rockchip/rk3328-doornet1.dts
+@@ -7,6 +7,7 @@
+ 
+ #include <dt-bindings/input/input.h>
+ #include <dt-bindings/gpio/gpio.h>
++#include "rk3328-dram-default-timing.dtsi"
+ #include "rk3328.dtsi"
+ 
+ / {
+@@ -120,6 +121,82 @@
+ 		regulator-min-microvolt = <5000000>;
+ 		regulator-max-microvolt = <5000000>;
+ 	};
++
++	dmc: dmc {
++		compatible = "rockchip,rk3328-dmc";
++		devfreq-events = <&dfi>;
++		center-supply = <&vdd_log>;
++		clocks = <&cru SCLK_DDRCLK>;
++		clock-names = "dmc_clk";
++		operating-points-v2 = <&dmc_opp_table>;
++		ddr_timing = <&ddr_timing>;
++		upthreshold = <40>;
++		downdifferential = <20>;
++		auto-min-freq = <786000>;
++		auto-freq-en = <1>;
++		#cooling-cells = <2>;
++		status = "okay";
++
++		ddr_power_model: ddr_power_model {
++			compatible = "ddr_power_model";
++			dynamic-power-coefficient = <120>;
++			static-power-coefficient = <200>;
++			ts = <32000 4700 (-80) 2>;
++			thermal-zone = "soc-thermal";
++		};
++	};
++
++	dmc_opp_table: dmc-opp-table {
++		compatible = "operating-points-v2";
++
++		rockchip,leakage-voltage-sel = <
++			1   10    0
++			11  254   1
++		>;
++		nvmem-cells = <&logic_leakage>;
++		nvmem-cell-names = "ddr_leakage";
++
++		opp-400000000 {
++			opp-hz = /bits/ 64 <400000000>;
++			opp-microvolt = <950000>;
++			opp-microvolt-L0 = <950000>;
++			opp-microvolt-L1 = <950000>;
++		};
++		opp-600000000 {
++			opp-hz = /bits/ 64 <600000000>;
++			opp-microvolt = <1025000>;
++			opp-microvolt-L0 = <1025000>;
++			opp-microvolt-L1 = <1000000>;
++		};
++		opp-786000000 {
++			opp-hz = /bits/ 64 <786000000>;
++			opp-microvolt = <1075000>;
++			opp-microvolt-L0 = <1075000>;
++			opp-microvolt-L1 = <1050000>;
++		};
++		opp-840000000 {
++			opp-hz = /bits/ 64 <840000000>;
++			opp-microvolt = <1075000>;
++			opp-microvolt-L0 = <1075000>;
++			opp-microvolt-L1 = <1050000>;
++		};
++		opp-924000000 {
++			opp-hz = /bits/ 64 <924000000>;
++			opp-microvolt = <1125000>;
++			opp-microvolt-L0 = <1125000>;
++			opp-microvolt-L1 = <1100000>;
++		};
++		opp-1056000000 {
++			opp-hz = /bits/ 64 <1056000000>;
++			opp-microvolt = <1175000>;
++			opp-microvolt-L0 = <1175000>;
++			opp-microvolt-L1 = <1150000>;
++		};
++	};
++};
++
++&dfi {
++	status = "okay";
+ };
+ 
+ &cpu0 {
+@@ -201,6 +278,7 @@
+ 				regulator-name = "vdd_log";
+ 				regulator-always-on;
+ 				regulator-boot-on;
++				regulator-init-microvolt = <1075000>;
+ 				regulator-min-microvolt = <712500>;
+ 				regulator-max-microvolt = <1450000>;
+ 				regulator-ramp-delay = <12500>;
+@@ -215,6 +293,7 @@
+ 				regulator-name = "vdd_arm";
+ 				regulator-always-on;
+ 				regulator-boot-on;
++				regulator-init-microvolt = <1225000>;
+ 				regulator-min-microvolt = <712500>;
+ 				regulator-max-microvolt = <1450000>;
+ 				regulator-ramp-delay = <12500>;
+@@ -419,3 +498,4 @@
+ 		realtek,led-data = <0x87>;
+ 	};
+ };
++