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Re: Booting the Debian installation CD on Powerbook G4 12"

On Sun, Feb 16, 2003 at 08:23:16PM +0100, Benjamin Herrenschmidt wrote:
> On Sun, 2003-02-16 at 19:42, paubert wrote:
> > > Well... There might be a bigger problem if the kernel reports 53Mhz
> > > on boot (that means upon frequency switch, the kernel internal timing
> > > delays may be incorrectly adjusted).
> > 
> > I'm still wondering why the timebase is not used to perform these
> > delays. I know that the 601 will add a slight complication, but 
> > at least I don't know of any system in which the bus frequency,
> > and therefore the timebase frequency, varies.
> I'm wondering the same thing actually ;) At least for 6xx/7xx/7xxx
> since other CPUs types have different timebase facilities (if any).

Well, the timebase and decremeter are part of the PPC architecture. 

BTW for the "53 MHz PB", what are the following properties of cpus/PowerPC,G4: 
- timebase-frequency 
- bus-frequency (should be 4 times timebase-frequency)

> Probably just nobody bothered doing it yet.
Ok, if I find time, I'll have a look at it.


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