On Fri, Nov 24, 2000 at 08:37:43AM +0000, Charles M. Hannum wrote:
> matthew green wrote:
> 
> > this is a "known problem".  this also happens on the macppc.
> 
> Eh?  Certainly doesn't happen on any of the Macs I use.  As witnessed by 
> the fact that this one boots just fine.  B-)

It happens on *some* macppc, the ones who have a CMD0646 IDE controller
(this is also the controller used on Ultra/5). For some reason the interrupt
seems to be disabled at the controller level (quite possible that OF disables
interrupts when accessing the disk), but there's no difference in the PCI
space config registers when booting from network or disk.
There's also no hint in the CMD0646 data sheet on where interrupts could
be disabled outside of the PCI space config. Either OF uses an undocumented
feature of the 0646, or interrupts are disabled elsewhere.

--
Manuel Bouyer <bouyer@antioche.eu.org>
--