Re: [PATCH v4 1/2] dt-bindings: cpufreq: add virtual cpufreq device

[Saravana Kannan]

On Wed, Nov 15, 2023 at 12:49 AM Marc Zyngier <maz@xxxxxxxxxx> wrote:
>
> On Sat, 11 Nov 2023 01:49:29 +0000,
> David Dai <davidai@xxxxxxxxxx> wrote:
> >
> > Adding bindings to represent a virtual cpufreq device.
> >
> > Virtual machines may expose MMIO regions for a virtual cpufreq device
> > for guests to read frequency information or to request frequency
> > selection. The virtual cpufreq device has an individual controller for
> > each frequency domain.
>
> I would really refrain form having absolute frequencies here. A
> virtual machine can be migrated, and there are *zero* guarantees that
> the target system has the same clock range as the source.
>
> This really should be a relative number, much like the capacity. That,
> at least, can be migrated across systems.

There's nothing in this patch that mandates absolute frequency.
In true KVM philosophy, we leave it to the VMM to decide.

-Saravana