Re: compat/native?

[Frank Wille <frank%phoenix.owl.de@localhost>]

Toru Nishimura wrote:

> Now, some NetBSD ports have pci/pciide_machdep.c to divert the
> compat case and the compat IDE HW is known working in legacy
> mode, that is, with legacy register addresses and legacy i8259 IRQs,
> 14 for primary and 15 for secondary.

Now I heard rumours that an IDE controller in compat mode may not work at all
on a non-x86 system ... ?


>> there is simple solution (or hack) to make it work perfectly: whenever
>> the native PCI interrupt handler for irq 14 is installed, I will
>> additionally install the same handler for irq 15. Tested. Works fine!
> 
> Is it really "native PCI interrupt handler" in irq (vague term ...) 15/14?

I think so. All registers which could reflect native-mode do that. I checked
them. Nevertheless the 8231 uses both irqs, although it should only use one?


> If s/native PCI/legacy/, then your story makes all sense.  The IDE HW
> is working as designed.

Compat/legacy mode doesn't work. I tried everything.

And the IDE interrupt routine register (0x4c) is fixed to 15/14 on the 8231,
you cannot change it to 14/14, according to the specs. Maybe this is the
"feature" causing the observed behaviour?


-- 
    _  Frank Wille (frank%phoenix.owl.de@localhost)
 _ //  http://sun.hasenbraten.de/~frank/
 \X/   Phx @ #AmigaGer