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Date: Sun, 12 Feb 2006 10:33:30 -0800
From: Eugene Surovegin <ebs@ebshome.net>
To: "dibacco@inwind.it" <dibacco@inwind.it>
Subject: Re: system tick in PPC
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On Sun, Feb 12, 2006 at 06:47:15PM +0100, dibacco@inwind.it wrote:
> Someone knows how the jiffies is incremented in PPC?
> Using PIT, Decrementer or what?

I think you should be looking at include/asm-powerpc/time.h, 
set_dec() & get_dec() functions. 

timer_interrupt() uses set_dec().

In short, usually PPC uses decrementer, but some sub-archs are special.

-- 
Eugene