On 2015-07-05 16:25, Serge Vakulenko wrote:
> On Wed, Jul 1, 2015 at 3:02 AM, Aurelien Jarno <aurel...@aurel32.net> wrote:
> > On 2015-06-30 21:12, Serge Vakulenko wrote:
> >> @@ -153,5 +153,6 @@ void cpu_mips_clock_init (CPUMIPSState *env)
> >> */
> >> if (!kvm_enabled()) {
> >> env->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, &mips_timer_cb,
> >> env);
> >> + env->count_freq = count_freq;
> >> }
> >> }
> >
> > So it means the value passed as an argument to this function is ignored
> > in the KVM case. I guess we want to be able to tell the kernel about the
> > request frequency.
>
> Sound like a new feature request for MIPS KVM developers. I cannot
> find any such possibility in the current KVM API.
Ok.
> My patch changes nothing for existing platforms like Malta, Fulong or
> MIPSsim. Everything continues to work as it is. Only for pic32mx7 cpu
> the clock rate is decreased to 40MHz. I'm not sure anybody could ever
> run KVM on this processor. :)
Yes, but you give the possibility to tweak the speed, so later someone
might wrongly pass a value different than 100MHz for a CPU usable with
KVM.
The way to go is to do add a comment with an assert:
if (kvm_enabled()) {
/* FIXME: KVM only supports a 100MHz clock. */
assert(count_freq == 100*1000*1000);
} else {
env->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, &mips_timer_cb, env);
env->count_freq = count_freq;
}
--
Aurelien Jarno GPG: 4096R/1DDD8C9B
aurel...@aurel32.net http://www.aurel32.net
