Welcome, Guest. Please login or register.

Author Topic: Amiga OS4 on old (PPC) Macs  (Read 63368 times)

Description:

0 Members and 1 Guest are viewing this topic.

Offline beakster2

  • Jr. Member
  • **
  • Join Date: Jul 2007
  • Posts: 63
    • Show all replies
Re: Amiga OS4 on old (PPC) Macs
« on: December 31, 2007, 01:15:47 PM »
Fantastic work guys!  Thanks to you it looks like we may soon have hardware to run OS4 on!  Once you've got it sorted I will buy a Mac and a legitimate copy of OS4 now that it is on sale! :)

Question though....

You can only do this at the moment on Mac Minis with Machine ID: PowerMac10,2 (Thats the 1.33 and 1.5 GHz version).  That version of the Mini was available with 32MB or 64MB of Video Ram.  Now what is stopping OS4 booting on other Mac models?

Is it OpenFirmware version?  Is it the Machine ID?  Is it the processor speed?  I believe all these things can be spoofed with OpenFirmware commands.  e.g. you should be able to make it think you have 1.5GHz instead of 1.42GHz by typing:
dev /cpus/PowerPC,G4@0
d# 1500000000 encode-int " clock-frequency" property

Ideally I'd like to run OS4 on an old eMac or one of the iMacs with the swivel screen mounted on the dome.  I know its only a matter of time until this is possible, but I just want to understand what the limiting factor is at the moment.

Thanks and keep up the good work! :)
 

Offline beakster2

  • Jr. Member
  • **
  • Join Date: Jul 2007
  • Posts: 63
    • Show all replies
Re: Amiga OS4 on old (PPC) Macs
« Reply #1 on: January 01, 2008, 05:33:24 PM »
Quote

HenryCase wrote:
http://mac-on-linux.sourceforge.net/
Are there any other VM solutions we could use?


PearPC is the one I was thinking of using to have a play with it.  It doesn't have a full Open Firmware implementation, but if it can run OS X, then OS4 should be easy with a bit of hacking.

I for one have been wanting to buy OS4 even since I used a development 68k version back in 2003.  An AmigaOne was out of my price range then, and I sold my BlizzardPPC back in 2000.  I've been waiting over 4 years to buy OS4, enough is enough.  If I can get it working on my PC under emulation, or on an old Mac I'll pay Hyperion for a copy and do it.  Otherwise God know how much longer Amiga Inc will keep us waiting for new hardware.
 

Offline beakster2

  • Jr. Member
  • **
  • Join Date: Jul 2007
  • Posts: 63
    • Show all replies
Re: Amiga OS4 on old (PPC) Macs
« Reply #2 on: January 01, 2008, 06:11:59 PM »
Why can't I buy the Classic version from Amikit?  Admittedly it will need some playing with, but everything should be there to get it working.
 

Offline beakster2

  • Jr. Member
  • **
  • Join Date: Jul 2007
  • Posts: 63
    • Show all replies
Re: Amiga OS4 on old (PPC) Macs
« Reply #3 on: January 06, 2008, 03:06:05 PM »
Yo,

I've been playing around with PearPC.  I haven't got very far but this is what I have discovered:

If you try and get PearPC to boot the AmigaMini.iso it says [IO/PROM] can't open boot file.  If you change the prom_bootmethod to select it shows the ISO has 3 partitions.  1 is Raw, 2 is Apple Partition Table and 3 is HFS.

I eventually gave up on trying to get PearPC to boot the ISO directly.  Without the commands you need to issue through the Open Firmware interface it doesn't work.

I then extracted the ISO to a directory so I could then manually specify the boot file.  Here are the lines I used in my PearPC.cfg:
prom_bootmethod = "force"
prom_loadfile = "iso\l\slb"
prom_env_bootpath = "iso"

This resulted in PearPC spitting out the following to the terminal:
[CPU/CPU] execution started at 00200078
[IO/PROM] unknown interpret size 175
interpret: " /chosen" find-package drop " memory" rot get-package-property drop
decode-int nip nip ihandle>phandle " reg" rot get-package-property drop decode-i
nt drop decode-int nip nip

I then tried booting the other file in the "l" directory, slb_v2_mm.  This gave the following screen output:

But it spat out:
JITC Warning: program exception: 00080000 00000000
in what appeared to be an endless loop.

That is as far as I've got with it.  I think I'm out of ideas on how to take it any further.  I might post something on the PearPC forum and see if they have any suggestions.

Cheers
 

Offline beakster2

  • Jr. Member
  • **
  • Join Date: Jul 2007
  • Posts: 63
    • Show all replies
Re: Amiga OS4 on old (PPC) Macs
« Reply #4 on: January 09, 2008, 11:43:41 PM »
Quote

lovrenco wrote:
After all, if Mac OsX can run, why couldn't this OS.


The thing is Mac OS X actually has really good built in hardware support.  There have been lots of different Macs over the years using lots of different video chipsets and stuff.

The Moana loader seems to have been written specifically for the 1.5GHz Mac Mini only.  Without the source code for Moana I don't think its any use on any other machine.

But I agree, with the PPC processor emulated, and a few implementations of OpenFirmware/OpenBIOS out there, surely the hard work has been done and tailoring these to emulate an AmigaOne should be simple if you know how.

If we were emulating Macs and PCs on our Amigas 15 years+ ago, why should this be much different.