Re: Dualboot Mac OS X and NetBSD on Power Mac?

[Chris Ross <cross+netbsd%distal.com@localhost>]

On Apr 27, 2010, at 20:21, Michael wrote:
> Actually it gets much further - it hangs when enabling the MMU and  
> so far I couldn't figure out why. Also, there's conflicting  
> information out there about BATs being emulated in bridge mode  
> ( most docs say nothing or no yet OpenBSD happily uses them anyway )
> Also, there is no support for the PCIe bridge in last generation G5s.

  Right.  And, I have a last-gen G5, so I'd need the PCIe bridge  
support too.  One more strike against me even considering this, I'm  
afraid.

> > A 32 bit kernel, however, seems like it shouldn't be that  
> > difficult.  This
> > did work at one point, the only problem is that point was about 5  
> > years ago
> > and the rest of the kernel has moved on while that code has  
> > apparently sat
> > still.  It needs someone to work through its problems to revive it.
>
> Apparently it didn't really use bridge mode anyway - just ran a  
> 64bit kernel being really, really careful about staying within 4GB.

  And, I'm not too concerned about that.  If the kernel ran user-land  
with any stability, or at all.  ;-)

> You can compile a 32bit G5 kernel ( or at lease I could not too long  
> ago ) - they don't reach userland however. 'Real' 64bit kernel hit  
> an #error elsewhere, somewhere in OF support IIRC. Otherwise, we  
> have a more or less generic SATA driver, no clue if that's enough  
> for the G5.

  I'd be happy to try running a 32-bit (or 64-bit "careful", or  
whatever else) to test on my last-gen G5, but without the PCIe bridge  
support, I'm sure it wouldn't get very far.

  If anyone wants me to try, and report back, let me know.  I only  
have the one G5 machine, which is also my primary [Mac OS X] desktop,  
so I don't know that I can be of any real dev help, even *if* I  
thought my skills were adequate.  :-)

  Thanks for all the information, and I hope to spur someone into  
getting more last-gen G5 Mac support working.  Happy to help where I  
can, but as noted, don't know that there's too much I can do/try.

  Anyone willing to work hard-core on it, I could likely be convinced  
to buy a last-gen G5 from eBay to contribute.  Can't cost that much  
any more, eh?

                         - Chris