[PATCH 08/10] arm64: dts: allwinner: h5: orange-pi-prime: Add CPU regulator supply

[Chen-Yu Tsai <wens@csie.org>]

The OrangePi Prime uses a Silergy SY8106A regulator to supply the CPU
cores. The fixed voltage when I2C programmed regulation is not in action
is slightly higher than 1.1V. The value in the device tree description
is based on calculations of the resistor values from the schematics.

Cc: Icenowy Zheng <icenowy@aosc.io>
Signed-off-by: Chen-Yu Tsai <wens@csie.org>

---

This patch is based on the schematics and has not been tested on an
actual board.
---
 .../allwinner/sun50i-h5-orangepi-prime.dts    | 28 +++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/arch/arm64/boot/dts/allwinner/sun50i-h5-orangepi-prime.dts b/arch/arm64/boot/dts/allwinner/sun50i-h5-orangepi-prime.dts
index b75ca4d7d001..e866a0734bb3 100644
--- a/arch/arm64/boot/dts/allwinner/sun50i-h5-orangepi-prime.dts
+++ b/arch/arm64/boot/dts/allwinner/sun50i-h5-orangepi-prime.dts
@@ -139,6 +139,10 @@
 	status = "okay";
 };
 
+&cpu0 {
+	cpu-supply = <&reg_vdd_cpux>;
+};
+
 &de {
 	status = "okay";
 };
@@ -222,6 +226,30 @@
 	status = "okay";
 };
 
+&r_i2c {
+	status = "okay";
+
+	reg_vdd_cpux: regulator@65 {
+		compatible = "silergy,sy8106a";
+		reg = <0x65>;
+		regulator-name = "vdd-cpux";
+		silergy,fixed-microvolt = <1108474>;
+		/*
+		 * The datasheet uses 1.1V as the minimum value of VDD-CPUX,
+		 * however both the Armbian DVFS table and the official one
+		 * have operating points with voltage under 1.1V, and both
+		 * DVFS table are known to work properly at the lowest
+		 * operating point.
+		 *
+		 * Use 1.0V as the minimum voltage instead.
+		 */
+		regulator-min-microvolt = <1000000>;
+		regulator-max-microvolt = <1300000>;
+		regulator-boot-on;
+		regulator-always-on;
+	};
+};
+
 &uart0 {
 	pinctrl-names = "default";
 	pinctrl-0 = <&uart0_pins_a>;
-- 
2.20.1