djdeeles's post in How to overclock Banana Pi with stable Armbian Linux version 4.19.62-sunxi was marked as the answer
Also you need to adjust voltage controller as below. I also attached my dtb file.
Goodluck. If you find something useful please let me know.
dcdc2 {
regulator-name = "vdd-cpu";
regulator-always-on;
regulator-min-microvolt = < 0xf4240 >;
regulator-max-microvolt = < 0x16e360 >;
phandle = < 0x03 >;
};
dcdc3 {
regulator-name = "vdd-int-dll";
regulator-always-on;
regulator-min-microvolt = < 0xf4240 >;
regulator-max-microvolt = < 0x16e360 >;
phandle = < 0xae >;
};
sun7i-a20-bananapi.dtb
