Re: [Qemu-devel] [PATCH 4/4] pl031: switch clock base to rtc_clock

[Peter Maydell]

On 20 January 2012 12:06, Paolo Bonzini <address@hidden> wrote:
> This lets the user specify the desired semantics.  By default, the RTC
> will follow adjustments from the host's NTP client, and will remain in
> sync when the virtual machine is stopped.  The previous behavior, which
> provides determinism with both icount and qtest, remains available with
> "-rtc clock=vm".
>
> pl031 supports migration, so we need to convert the time
> base from rtc_clock to vm_clock and back for backwards compatibility.

If it would be cleaner I'm entirely happy for us to do a version
bump and break binary compatibility. (We bump the version on
the CPUState pretty regularly anyhow; save/load for ARM devices
currently is mostly for the benefit of snapshot save/restore rather
than between-qemu-versions migration.)

-- PMM