[PATCH 2/5] Implement generic time of day clocksource for powerpc machines.
dwalker at mvista.com
Thu Sep 20 11:54:41 EST 2007
On Thu, 2007-09-20 at 11:46 +1000, Paul Mackerras wrote:
> Daniel Walker writes:
> > On Thu, 2007-09-20 at 10:52 +1000, Paul Mackerras wrote:
> > > Daniel Walker writes:
> > >
> > > > If you switch to the rtc do the shift and mult need to change?
> > >
> > > You can't switch; any given CPU chip will have either the RTC or the
> > > timebase but not both.
> > The code is switching between to clock read functions .. If they are
> What part of "you can't switch" wasn't clear? __USE_RTC() is a
> constant on any given machine.
Maybe say "It a constant" up front .. The value that is output from the
clocksource read is converted to nanoseconds .. This clocksource is only
designed to work with the timebase, so it doesn't make sense to output
an rtc value.
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