Enable DVFS for the Odroid-N2 by setting the clock, OPP and supply for each cores of each CPU clusters.
The first cluster uses the "VDDCPU_B" power supply, and the second cluster uses the "VDDCPU_A" power supply. Each power supply can achieve 0.73V to 1.01V using 2 distinct PWM outputs 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 of each cluster 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.blumensti...@googlemail.com> Signed-off-by: Neil Armstrong <narmstr...@baylibre.com> --- .../boot/dts/amlogic/meson-g12b-odroid-n2.dts | 96 +++++++++++++++++++ 1 file changed, 96 insertions(+) diff --git a/arch/arm64/boot/dts/amlogic/meson-g12b-odroid-n2.dts b/arch/arm64/boot/dts/amlogic/meson-g12b-odroid-n2.dts index 4e916e1f71f7..777bfb938854 100644 --- a/arch/arm64/boot/dts/amlogic/meson-g12b-odroid-n2.dts +++ b/arch/arm64/boot/dts/amlogic/meson-g12b-odroid-n2.dts @@ -115,6 +115,44 @@ /* FIXME: actually controlled by VDDCPU_B_EN */ }; + vddcpu_a: regulator-vddcpu-a { + /* + * MP8756GD Regulator. + */ + compatible = "pwm-regulator"; + + regulator-name = "VDDCPU_A"; + regulator-min-microvolt = <721000>; + regulator-max-microvolt = <1022000>; + + vin-supply = <&main_12v>; + + pwms = <&pwm_ab 0 1250 0>; + pwm-dutycycle-range = <100 0>; + + regulator-boot-on; + regulator-always-on; + }; + + vddcpu_b: regulator-vddcpu-b { + /* + * Silergy SY8120B1ABC Regulator. + */ + compatible = "pwm-regulator"; + + regulator-name = "VDDCPU_B"; + 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; + }; + hub_5v: regulator-hub_5v { compatible = "regulator-fixed"; regulator-name = "HUB_5V"; @@ -246,6 +284,48 @@ status = "okay"; }; +&cpu0 { + cpu-supply = <&vddcpu_b>; + operating-points-v2 = <&cpu_opp_table_0>; + clocks = <&clkc CLKID_CPU_CLK>; + clock-latency = <50000>; +}; + +&cpu1 { + cpu-supply = <&vddcpu_b>; + operating-points-v2 = <&cpu_opp_table_0>; + clocks = <&clkc CLKID_CPU_CLK>; + clock-latency = <50000>; +}; + +&cpu100 { + cpu-supply = <&vddcpu_a>; + operating-points-v2 = <&cpub_opp_table_1>; + clocks = <&clkc CLKID_CPUB_CLK>; + clock-latency = <50000>; +}; + +&cpu101 { + cpu-supply = <&vddcpu_a>; + operating-points-v2 = <&cpub_opp_table_1>; + clocks = <&clkc CLKID_CPUB_CLK>; + clock-latency = <50000>; +}; + +&cpu102 { + cpu-supply = <&vddcpu_a>; + operating-points-v2 = <&cpub_opp_table_1>; + clocks = <&clkc CLKID_CPUB_CLK>; + clock-latency = <50000>; +}; + +&cpu103 { + cpu-supply = <&vddcpu_a>; + operating-points-v2 = <&cpub_opp_table_1>; + clocks = <&clkc CLKID_CPUB_CLK>; + clock-latency = <50000>; +}; + &ext_mdio { external_phy: ethernet-phy@0 { /* Realtek RTL8211F (0x001cc916) */ @@ -317,6 +397,22 @@ pinctrl-names = "default"; }; +&pwm_ab { + pinctrl-0 = <&pwm_a_e_pins>; + pinctrl-names = "default"; + clocks = <&xtal>; + clock-names = "clkin0"; + status = "okay"; +}; + +&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"; -- 2.22.0
