arm64: overlays-rockpi4: Add rk3399 overclocking support

Author: ZhuBin32

arch/arm64/boot/dts/rockchip/overlays-rockpi4/Makefile

@@ -13,7 +13,8 @@ dtbo-$(CONFIG_ARCH_ROCKCHIP) += \
 	spi1-flash.dtbo \
 	hifiberry-dac.dtbo \
 	hifiberry-dacplus.dtbo \
-	raspberrypi-7-inch-lcd.dtbo
+	raspberrypi-7-inch-lcd.dtbo \
+	cpufreq.dtbo
 
 targets += dtbs dtbs_install
 targets += $(dtbo-y)

arch/arm64/boot/dts/rockchip/overlays-rockpi4/cpufreq-overlay.dts

@@ -0,0 +1,29 @@
+/dts-v1/;
+/plugin/;
+
+/ {
+	model = "ROCK PI 4B";
+	compatible = "rockchip,rockpi","rockchip,rk3399";
+
+	fragment@0 {
+		target = <&cluster0_opp>;
+
+		__overlay__ {
+			opp-1512000000 {
+				opp-hz = /bits/ 64 <1512000000>;
+				opp-microvolt = <1150000>;
+			};
+		};
+	};
+
+	fragment@1 {
+		target = <&cluster1_opp>;
+
+		__overlay__ {
+			opp-2016000000 {
+				opp-hz = /bits/ 64 <2016000000>;
+				opp-microvolt = <1250000>;
+			};
+		};
+	};
+};

arch/arm64/boot/dts/rockchip/overlays-rockpi4/hw_intfc.conf

@@ -55,3 +55,6 @@ intfc:dtoverlay=console-on-ttyS2
 
 #enable raspberry pi official 7 inch LCD support
 #intfc:dtoverlay=raspberrypi-7-inch-lcd
+
+# setting cpu frequency over-2GHz
+#intfc:dtoverlay=cpufreq