[RFC/RFT 12/14] arm64: dts: meson-g12a: enable DVFS on G12A boards

From: Neil Armstrong
Date: Thu Jun 20 2019 - 11:06:42 EST

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

Signed-off-by: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
---
.../boot/dts/amlogic/meson-g12a-sei510.dts | 55 +++++++++++++++++++
.../boot/dts/amlogic/meson-g12a-u200.dts | 55 +++++++++++++++++++
.../boot/dts/amlogic/meson-g12a-x96-max.dts | 52 ++++++++++++++++++
3 files changed, 162 insertions(+)

diff --git a/arch/arm64/boot/dts/amlogic/meson-g12a-sei510.dts b/arch/arm64/boot/dts/amlogic/meson-g12a-sei510.dts
index bd26b35102ff..be45437c51e1 100644
--- a/arch/arm64/boot/dts/amlogic/meson-g12a-sei510.dts
+++ b/arch/arm64/boot/dts/amlogic/meson-g12a-sei510.dts
@@ -129,6 +129,25 @@
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 @@
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>;
@@ -339,6 +386,14 @@
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>;
diff --git a/arch/arm64/boot/dts/amlogic/meson-g12a-u200.dts b/arch/arm64/boot/dts/amlogic/meson-g12a-u200.dts
index 332a4b27174b..b6bd96ee394a 100644
--- a/arch/arm64/boot/dts/amlogic/meson-g12a-u200.dts
+++ b/arch/arm64/boot/dts/amlogic/meson-g12a-u200.dts
@@ -136,6 +136,25 @@
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;
+ };
+
sound {
compatible = "amlogic,axg-sound-card";
model = "G12A-U200";
@@ -305,6 +324,34 @@
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>;
@@ -369,6 +416,14 @@
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";
diff --git a/arch/arm64/boot/dts/amlogic/meson-g12a-x96-max.dts b/arch/arm64/boot/dts/amlogic/meson-g12a-x96-max.dts
index d37868d21114..099ccf67547e 100644
--- a/arch/arm64/boot/dts/amlogic/meson-g12a-x96-max.dts
+++ b/arch/arm64/boot/dts/amlogic/meson-g12a-x96-max.dts
@@ -132,6 +132,22 @@
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 @@
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 @@
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) */
--
2.21.0