>> Check and see cpu_intr()::cobalt/cobalt/machdep.c as a minimalist example.
>
> I have already looked at it, and I confess I don't  really understand what he
> does : he uses a magic number 0x14000c18, transforms it into a kseg1 address,
> and checks that the bit 8 is on.
> Well, I confess it seems a little obscure to me.
> What does this address mean ?

It seems NetBSD/cobalt uses Galileo-T's GT64011 PCI system controller
to feed hardclock(), while CPU generated INT_5 for statclock() which
is #if 0'ed out. 

Tohru Nishimura
Nara Institute of Science and Technology