Subject: Re: [PATCH 2/5] Implement generic time of day clocksource for powerpc machines.

From: David Gibson <[email-masked]>
Date: Thu, 20 Sep 2007 13:29:35 +1000

On Wed, Sep 19, 2007 at 06:54:41PM -0700, Daniel Walker wrote:
> 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.

I believe "rtc" in a 601 context means something different to "rtc" in
a general context...

-- 
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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