arm: dts: overlay: add Vanxoak HD-RK3506G-EVB all-opp overlay

The device defaults shipped with a LDO which only provides 960mV by
default (told by vendor support), and it will only activate OPPs up to
1512MHz. This commit adds an overlay to fake the LDO to 1100mV to
activate the full OPP table including 1608MHz.

Author: SeeleVolleri

arch/arm/boot/dts/overlay/Makefile

@@ -17,7 +17,8 @@ dtbo-$(CONFIG_ARCH_ROCKCHIP) += \
 	rockchip-luckfox-lyra-zero-w-spi1-1cs-spidev.dtbo \
 	rockchip-luckfox-lyra-zero-w-spi1-2cs-spidev.dtbo \
 	rockchip-rk3506-disable-ethernet0.dtbo \
-	rockchip-rk3506-disable-ethernet1.dtbo
+	rockchip-rk3506-disable-ethernet1.dtbo \
+	rockchip-vanxoak-hd-rk3506g-evb-all-opp.dtbo
 
 dtbotxt-$(CONFIG_ARCH_ROCKCHIP) += \
 	README.rockchip-overlays

arch/arm/boot/dts/overlay/rockchip-vanxoak-hd-rk3506g-evb-all-opp.dts

@@ -0,0 +1,17 @@
+// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+/dts-v1/;
+/plugin/;
+
+/ {
+	metadata {
+		title = "Enable all CPU OPPs";
+		compatible = "vanxoak,hd-rk3506g-evb", "rockchip,rk3506";
+		category = "misc";
+		description = "Fake vdd_arm LDO to 1100mV to activate all CPU OPPs.";
+	};
+};
+
+&vdd_arm {
+	regulator-min-microvolt = <1100000>;
+	regulator-max-microvolt = <1100000>;
+};