feat: add radxa zero3 poe overlay

Signed-off-by: Alvin Xie <[email protected]>

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

@@ -300,6 +300,7 @@ dtb-$(CONFIG_CPU_RK3568) += \
 	radxa-zero3-radxa-camera-8m.dtbo \
 	radxa-zero3-rpi-camera-v1.3.dtbo \
 	radxa-zero3-rpi-camera-v2.dtbo \
+	radxa-zero3-poe-hat.dtbo \
 	radxa-zero3-disabled-ethernet.dtbo \
 	radxa-zero3-disabled-wireless.dtbo \
 	rock-3a-radxa-display-8hd.dtbo \

arch/arm64/boot/dts/rockchip/overlays/radxa-zero3-poe-hat.dts

@@ -0,0 +1,55 @@
+/dts-v1/;
+/plugin/;
+
+#include <dt-bindings/gpio/gpio.h>
+#include <dt-bindings/pinctrl/rockchip.h>
+#include <dt-bindings/pwm/pwm.h>
+#include <dt-bindings/thermal/thermal.h>
+
+/ {
+	metadata {
+		title = "Enable Radxa ZERO 3E PoE HAT";
+		category = "misc";
+		compatible = "radxa,zero3";
+		description = "Enable Radxa ZERO 3E PoE HAT.";
+		exclusive = "GPIO3_C3";
+		package = "rsetup-config-thermal-governor-step-wise";
+	};
+};
+
+&{/} {
+	radxa_poe_pwm: radxa-poe-pwm {
+		compatible = "pwm-gpio";
+		#pwm-cells = <3>;
+		pwm-gpio = <&gpio3 RK_PC3 GPIO_ACTIVE_HIGH>;
+	};
+
+	radxa_poe_fan: radxa-poe-fan {
+		compatible = "pwm-fan";
+		#cooling-cells = <2>;
+		cooling-min-state = <0>;
+		cooling-max-state = <4>;
+		cooling-levels = <0 64 128 192 255>;
+		pwms = <&radxa_poe_pwm 0 40000 PWM_POLARITY_INVERTED>;
+	};
+};
+
+&threshold {
+	temperature = <60000>;
+};
+
+&soc_thermal {
+	sustainable-power = <5000>; /* milliwatts */
+	cooling-maps {
+		map2 {
+			trip = <&target>;
+			cooling-device = <&radxa_poe_fan THERMAL_NO_LIMIT THERMAL_NO_LIMIT>;
+			contribution = <8192>;
+		};
+		map3 {
+			trip = <&threshold>;
+			cooling-device = <&radxa_poe_fan THERMAL_NO_LIMIT THERMAL_NO_LIMIT>;
+			contribution = <8192>;
+		};
+	};
+};