Re: [Qemu-ppc] [Qemu-devel] [PATCH v2 3/3] 40p: add fixed IRQ routing for LSI SCSI device

[Artyom Tarasenko]

On Thu, Sep 13, 2018 at 5:30 PM Mark Cave-Ayland
<address@hidden> wrote:
>
> On 13/09/18 15:21, Artyom Tarasenko wrote:
>
> > On Sat, Sep 8, 2018 at 11:11 AM Mark Cave-Ayland
> > <address@hidden> wrote:
> >>
> >> Whilst the PReP specification describes how all PCI IRQs are routed via IRQ
> >> 15 on the interrupt controller, the real 40p machine has routing quirk in
> >> that the LSI SCSI device is routed to IRQ 13.
> >
> > Is it a routing quirk or does 40p use both 15 and 13?
> > I used both in my AIX experiments and AIX seemed to be happy about it.
> > But maybe AIX simply doesn't care as long as the residual data is correct.
> >
> > Artyom
>
> If you boot the Linux sandalfoot zImage then you can see the LSI IRQ
> change from 15 to 13 just by changing the model name in OpenBIOS to
> match that of a real 40p (compare with
> http://www.juneau-lug.org/sandalfoot.php). There's also similar code
> that you can see in NetBSD.
>
> My guess would be that AIX does the "right thing" and parses the
> residual data correctly as expected.

This does indeed make sense.

Reviewed-by: Artyom Tarasenko <address@hidden>

-- 
Regards,
Artyom Tarasenko

SPARC and PPC PReP under qemu blog: http://tyom.blogspot.com/search/label/qemu