Bill.Holler at Sun.COM wrote: > Li, Aubrey wrote: >> Bill.Holler at Sun.COM wrote: >> >> >>> Li, Aubrey wrote: >>> >>>> Bill Holler wrote: >>>> >>>> >>>> >>>>>>> You can probably take it from another CPU that's not in deep-c >>>>>>> state (if there is one?) >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>> Yes. Our initial thoughts are to sync up with a running CPU >>>>>> via cross call. We need to run performance experiments with >>>>>> different implementations to see what the costs are. >>>>>> >>>>>> >>>>>> >>>>> Synching TSC/APIC with a running cpu is potentially much more >>>>> accurate than using the HPET. However this will induce drift. >>>>> >>>>> >>>>> >>>> if all the cpus are in the deeper c-state,...? >>>> >>>> >>> An external source such as the HPET or platform pm timer needs to >>> be used if all cpus are in deeper c-state. :-) >>> >>> >> >> Are you working on the ACPI timer driver as well? >> > > Yes. > > Do you have an estimate for how many systems have an ACPI timer > but do not have an HPET timer? > > Bill > I have no idea, ;-)
-Aubrey
