Re: G5 powermacs

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

Hello,

On Sun, 4 Jun 2017 16:03:13 +0100
Sevan Janiyan <venture37%geeklan.co.uk@localhost> wrote:

> >> Most recently April 2013, which was very fruitful in relation to
> >> patches.  
> Uncommitted patches that is.
> 
> On 04/06/2017 15:33, Havard Eidnes wrote:> 5926884 Invalid memory access
> at  %SRR0: 00000000.00e0bed8  %SRR1:
> > 10000000.00003030 ok 0 >  
> Same thing.

When I was working on incorporating G5 support ( patches from someone
else, I just helped getting them into the tree ) this was what I got:

- kernels had to be loaded directly, without ofwboot.xcf, at least for
  netbooting. There's a size limit imposed by OF which seems to be
  about 4MB, bigger kernels will randomly crash or not load at all
  IIRC. G5s don't have BARs, I'm not sure ofwboot knows that.
- the whole thing runs in 32bit bridge mode, so no more than 2GB of RAM
  ( the address space layout is similar to G4 Macs in the lower 4GB -
  2GB for mappable memory, 2GB for PCI, other registers, firmware ROMs
  ) - additional memory is mapped above 4GB.
- there is code to initialize the SMU, which for some reason never
  worked on mine. The effect is that after a minute or so all fans will
  start blowing at full speed. The guy who sent the patch said it
  worked for him.
- there are drivers for the PCIe host bridge and HT stuff, at least SATA
  was supposed to work, possibly ethernet. I don't remember details.

have fun
Michael