Re: [RFC/RFT v3 12/14] arm64: dts: meson-g12a: enable DVFS on G12A boards

From: Martin Blumenstingl
Date: Tue Jul 02 2019 - 20:49:11 EST


On Mon, Jul 1, 2019 at 11:13 AM Neil Armstrong <narmstrong@xxxxxxxxxxxx> wrote:
>
> 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>
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@xxxxxxxxxxxxxx>