I’m working bare-metal on the Rock Pi 4B. I use ARM’s PSCI to turn on the other CPUs after boot. They start with a low frequency. Sadly, PSCI only handles power on/off, not frequency scaling. For my use-case, I want all cores running at their max. speed. How can I set them to their max frequency?
I tried to get an idea from the Linux Kernel. My best guess so far is to enable the “right” values via the RK808 but I have no idea what these are and how to set them correctly.
Any help is greatly appreciated.
Setting the CPU frequency
You can refer how to set the cpu freq from command line:
How to overclock the ROCK Pi 4B to 2Ghz:
Thank you @jack but this is not what I was looking fore because in my case I do not have linux running. So I need to talk to the hardware directly. My best guess right now is the RK808 power controller but I do not know the right values.
The frequency is set by the voltage to the ARM core, this is implemented by DVFS: