[Cbe-oss-dev] cpufreq driver on ps3 platform

[Arnd Bergmann]

On Monday 20 July 2009, Vaibhav wrote:
> I'm trying to implement dynamic voltage scaling algorithm on the cell
> processor on the PS3. Is it possible to change the freq on the ps3 platform
> using cpufreq. I've had no luck so far. Im guessing because of it not being
> activated in the BIOS. Is there any workaround? Would it be possible to
> write directly to the register in the processor concerning the voltage
> selection? Please help me out. my whole project depends on this part. any
> suggestions will do.

It's not possible. The processor supports it, and Linux has the driver
for it in arch/powerpc/platforms/cell/cbe_cpufreq.c for bare-metal systems.
However, on the PS3 the hypervisor is in charge of setting the frequency
and it does not export this to Linux.

	Arnd <><