Re: Can't boot NetBSD on Powermac G5 (invalid memory access)

[Michael <macallan%netbsd.org@localhost>]

Hello,

On Wed, 13 Mar 2019 10:50:54 +0100
"Jost Menke" <cyberlab%gmx.de@localhost> wrote:

> > Gesendet: Dienstag, 12. März 2019 um 15:01 Uhr
> > Von: "Sevan Janiyan" <venture37%geeklan.co.uk@localhost>
> > An: "Jost Menke" <cyberlab%gmx.de@localhost>, port-macppc%NetBSD.org@localhost
> > Betreff: Re: Can't boot NetBSD on Powermac G5 (invalid memory access)  
> 
> > See[1] on how to run NetBSD-HEAD on your G5s via loading the kernel via
> > tftp directly or using ofwboot.
> >
> > Sevan
> > [1] http://mail-index.netbsd.org/port-macppc/2019/02/20/msg002555.html
> >   
> 
> I tried that and got the same error.

Hmm...
First, which kernel did you try to (net)boot? The GENERIC ones don't
have G5 support. The ones that do are POWERMAC_G5 and POWERMAC_G5.MP.
Second, how big is the kernel image you're trying to boot? For
netbooting they must be no bigger than 4MB and a little bit ( not sure
how much exactly, it's an undocumented Apple OF limitation ). Did you
use -current ofwboot.xcf or something older? The older ones lack G5
support.
Finally, there seems to be a(nother) problem with ofwboot.xcf and very
recent kernels that are over 5MB, I just ran into that myself when
trying to get the xhci driver to work on my PCIe G5 - kernels with
XHCI_DEBUG won't boot. Not sure what exactly causes it though, I only
started to see it with kernels build with gcc 7.4, but that's probably
coincidence.
If nothing else, I can send you a kernel that boots on my PowerMac7,3.

Also, nothing requires ofwboot.xcf and the kernel to be on the same
disk, you can load ofwboot.xcf from a HFS partition and the kernel from
a CD ( something like boot hd:ofwboot.xcf cd:netbsd.g5 )
A -current iso image should have at least a working ofwboot.xcf though.

That said, G5 support is still quite experimental, especially SMP. It
works more or less reliably on my 11,2 and 7,3, other models will need
adjustments with at least the fan control system ( that's all
software... ).

have fun
Michael