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Date: Fri, 21 Sep 2007 14:59:31 +1000
From: Paul Mackerras <paulus@samba.org>
To: Daniel Walker <dwalker@mvista.com>
Subject: Re: [PATCH v2 2/4] Implement generic time of day clocksource for
	powerpc machines.
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Cc: linuxppc-dev@ozlabs.org, Thomas Gleixner <tglx@linutronix.de>,
	Realtime Kernel <linux-rt-users@vger.kernel.org>
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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. :)

Paul.