[PATCH v2 2/4] Implement generic time of day clocksource for powerpc machines.

David Gibson david at gibson.dropbear.id.au
Fri Sep 21 16:43:21 EST 2007

On Fri, Sep 21, 2007 at 02:59:31PM +1000, Paul Mackerras wrote:
> Daniel Walker writes:
> > I don't think the RTC frequency isn't the same as the timebase? Seems
> > like the RTC only case about seconds at the lowest level. If that's the
> > case then the jiffies clock might be better to use .. The other thing I
> > wonder is if the __USE_RTC boards might have lower level clocks that
> > could be used instead ..
> It's OK, the RTC isn't what you think it is, it's a pair of
> CPU-internal registers which count seconds and nanoseconds.  On
> processors with the RTC, tb_ticks_per_sec is initialized to
> 1000000000.  Trust me, this code is OK. :)

Indeed..  I'm wondering if we should do a s/rtc/ppc601rtc/ or
something.  Otherwise people will keep making this mistake and be

David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!

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