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>
diff --git a/arch/arm64/boot/dts/amlogic/meson-g12a-sei510.dts b/arch/arm64/boot/dts/amlogic/meson-g12a-sei510.dts
index 12aa7ea..c9fa23a 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>;
@@ -345,6 +392,14 @@
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>;