arm64: dts: meson-g12a: enable DVFS on G12A boards

Enable DVFS for the U200, SEI520 and X96-Max Amlogic G12A based board
by setting the clock, OPP and supply for each CPU cores.

The CPU cluster power supply can achieve 0.73V to 1.01V using a PWM
output clocked at 800KHz with an inverse duty-cycle.

DVFS has been tested by running the arm64 cpuburn at [1] and cycling
between all the possible cpufreq translations and checking the final
frequency using the clock-measurer, script at [2].

[1] https://github.com/ssvb/cpuburn-arm/blob/master/cpuburn-a53.S
[2] https://gist.github.com/superna9999/d4de964dbc0f84b7d527e1df2ddea25f

Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Kevin Hilman <khilman@baylibre.com>
Tested-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Kevin Hilman <khilman@baylibre.com>

arch/arm64/boot/dts/amlogic/meson-g12a-sei510.dts

@@ -129,6 +129,25 @@ vddao_3v3_t: regultor-vddao_3v3_t {
 		enable-active-high;
 	};
 
+	vddcpu: regulator-vddcpu {
+		/*
+		 * SY8120B1ABC DC/DC Regulator.
+		 */
+		compatible = "pwm-regulator";
+
+		regulator-name = "VDDCPU";
+		regulator-min-microvolt = <721000>;
+		regulator-max-microvolt = <1022000>;
+
+		vin-supply = <&dc_in>;
+
+		pwms = <&pwm_AO_cd 1 1250 0>;
+		pwm-dutycycle-range = <100 0>;
+
+		regulator-boot-on;
+		regulator-always-on;
+	};
+
 	vddio_ao1v8: regulator-vddio_ao1v8 {
 		compatible = "regulator-fixed";
 		regulator-name = "VDDIO_AO1V8";
@@ -297,6 +316,34 @@ &clkc_audio {
 	status = "okay";
 };
 
+&cpu0 {
+	cpu-supply = <&vddcpu>;
+	operating-points-v2 = <&cpu_opp_table>;
+	clocks = <&clkc CLKID_CPU_CLK>;
+	clock-latency = <50000>;
+};
+
+&cpu1 {
+	cpu-supply = <&vddcpu>;
+	operating-points-v2 = <&cpu_opp_table>;
+	clocks = <&clkc CLKID_CPU_CLK>;
+	clock-latency = <50000>;
+};
+
+&cpu2 {
+	cpu-supply = <&vddcpu>;
+	operating-points-v2 = <&cpu_opp_table>;
+	clocks = <&clkc CLKID_CPU_CLK>;
+	clock-latency = <50000>;
+};
+
+&cpu3 {
+	cpu-supply = <&vddcpu>;
+	operating-points-v2 = <&cpu_opp_table>;
+	clocks = <&clkc CLKID_CPU_CLK>;
+	clock-latency = <50000>;
+};
+
 &cvbs_vdac_port {
 	cvbs_vdac_out: endpoint {
 		remote-endpoint = <&cvbs_connector_in>;
@@ -345,6 +392,14 @@ &ir {
 	pinctrl-names = "default";
 };
 
+&pwm_AO_cd {
+	pinctrl-0 = <&pwm_ao_d_e_pins>;
+	pinctrl-names = "default";
+	clocks = <&xtal>;
+	clock-names = "clkin1";
+	status = "okay";
+};
+
 &pwm_ef {
 	status = "okay";
 	pinctrl-0 = <&pwm_e_pins>;

arch/arm64/boot/dts/amlogic/meson-g12a-u200.dts

@@ -129,6 +129,24 @@ vddao_3v3: regulator-vddao_3v3 {
 		regulator-always-on;
 	};
 
+	vddcpu: regulator-vddcpu {
+		/*
+		 * MP8756GD Regulator.
+		 */
+		compatible = "pwm-regulator";
+
+		regulator-name = "VDDCPU";
+		regulator-min-microvolt = <721000>;
+		regulator-max-microvolt = <1022000>;
+
+		vin-supply = <&main_12v>;
+
+		pwms = <&pwm_AO_cd 1 1250 0>;
+		pwm-dutycycle-range = <100 0>;
+
+		regulator-boot-on;
+		regulator-always-on;
+	};
 };
 
 &cec_AO {
@@ -145,6 +163,34 @@ &cecb_AO {
 	hdmi-phandle = <&hdmi_tx>;
 };
 
+&cpu0 {
+	cpu-supply = <&vddcpu>;
+	operating-points-v2 = <&cpu_opp_table>;
+	clocks = <&clkc CLKID_CPU_CLK>;
+	clock-latency = <50000>;
+};
+
+&cpu1 {
+	cpu-supply = <&vddcpu>;
+	operating-points-v2 = <&cpu_opp_table>;
+	clocks = <&clkc CLKID_CPU_CLK>;
+	clock-latency = <50000>;
+};
+
+&cpu2 {
+	cpu-supply = <&vddcpu>;
+	operating-points-v2 = <&cpu_opp_table>;
+	clocks = <&clkc CLKID_CPU_CLK>;
+	clock-latency = <50000>;
+};
+
+&cpu3 {
+	cpu-supply = <&vddcpu>;
+	operating-points-v2 = <&cpu_opp_table>;
+	clocks = <&clkc CLKID_CPU_CLK>;
+	clock-latency = <50000>;
+};
+
 &cvbs_vdac_port {
 	cvbs_vdac_out: endpoint {
 		remote-endpoint = <&cvbs_connector_in>;
@@ -197,6 +243,14 @@ &i2c3 {
 	pinctrl-names = "default";
 };
 
+&pwm_AO_cd {
+	pinctrl-0 = <&pwm_ao_d_e_pins>;
+	pinctrl-names = "default";
+	clocks = <&xtal>;
+	clock-names = "clkin1";
+	status = "okay";
+};
+
 /* SD card */
 &sd_emmc_b {
 	status = "okay";

arch/arm64/boot/dts/amlogic/meson-g12a-x96-max.dts

@@ -132,6 +132,22 @@ vddao_3v3: regulator-vddao_3v3 {
 		regulator-always-on;
 	};
 
+	vddcpu: regulator-vddcpu {
+		compatible = "pwm-regulator";
+
+		regulator-name = "VDDCPU";
+		regulator-min-microvolt = <721000>;
+		regulator-max-microvolt = <1022000>;
+
+		vin-supply = <&dc_in>;
+
+		pwms = <&pwm_AO_cd 1 1250 0>;
+		pwm-dutycycle-range = <100 0>;
+
+		regulator-boot-on;
+		regulator-always-on;
+	};
+
 	sound {
 		compatible = "amlogic,axg-sound-card";
 		model = "G12A-X96-MAX";
@@ -242,6 +258,34 @@ &clkc_audio {
 	status = "okay";
 };
 
+&cpu0 {
+	cpu-supply = <&vddcpu>;
+	operating-points-v2 = <&cpu_opp_table>;
+	clocks = <&clkc CLKID_CPU_CLK>;
+	clock-latency = <50000>;
+};
+
+&cpu1 {
+	cpu-supply = <&vddcpu>;
+	operating-points-v2 = <&cpu_opp_table>;
+	clocks = <&clkc CLKID_CPU_CLK>;
+	clock-latency = <50000>;
+};
+
+&cpu2 {
+	cpu-supply = <&vddcpu>;
+	operating-points-v2 = <&cpu_opp_table>;
+	clocks = <&clkc CLKID_CPU_CLK>;
+	clock-latency = <50000>;
+};
+
+&cpu3 {
+	cpu-supply = <&vddcpu>;
+	operating-points-v2 = <&cpu_opp_table>;
+	clocks = <&clkc CLKID_CPU_CLK>;
+	clock-latency = <50000>;
+};
+
 &cvbs_vdac_port {
 	cvbs_vdac_out: endpoint {
 		remote-endpoint = <&cvbs_connector_in>;
@@ -279,6 +323,14 @@ &ir {
 	pinctrl-names = "default";
 };
 
+&pwm_AO_cd {
+	pinctrl-0 = <&pwm_ao_d_e_pins>;
+	pinctrl-names = "default";
+	clocks = <&xtal>;
+	clock-names = "clkin1";
+	status = "okay";
+};
+
 &ext_mdio {
 	external_phy: ethernet-phy@0 {
 		/* Realtek RTL8211F (0x001cc916) */