Am 2017-04-14 um 11:33 schrieb Linux User #330250:
To my understanding only NewWorld Macs are supported. But then, *all*
NewWorld Macs are, and those are "old" too by now. This should include
all Macs which are called "Power Mac" (before it was "Power
Macintosh"). And AFAIK the last "Power Macintosh G3" was one of the
first NewWorld Macs.
I'd like to correct this, I was mistaken.
Anything called "Power Macintosh" is most definitely OldWorld. The first
NewWorld Mac ist the iMac "Bondi" [iMac,1] from 1998 and the first Power
Mac to be NewWorld is actually the first one to be officially called
"Power Mac" i.e. the Power Mac G3 Blue & White (B&W) [PowerMac1,1] from
1999. The first NewWorld Laptop was the "Lombard" [PowerBook1,1], also
from 1999.
As far as I could find out – and I hope I got this one right – Open
Firmware introduced the Model Identifier started with 3.x. It was when
Apple got hands on the source code of Open Firmware, which was
originally developed by Sun Microsystems in the late 1980ies. (First
release 1988 or so?)
From http://osxbook.com/book/bonus/ancient/whatismacosx/arch_boot.html:
"The "Old World" Macs had various issues with the implementation of Open
Firmware, which in turn caused many booting problems for Apple
engineers, and even more problems for the PowerPC Linux port. Now, Apple
had access to the firmware's source. They solved most of the problems
either via NVRAM patches, or by integrating required changes into BootX
itself (in the instances where the changes could not be implemented as
patches). As BootX matured, Apple added support for ext2 and ELF with
the goal of making the platform more amenable to PowerPC Linux."
Prior Macs were henceforth referred to as "OldWorld" - but only WITH
Open Firmware, because Open Firmware 1.x and 2.x was already used but
not extensively and the Macintosh ROM (Macintosh Toolbox) was still part
of the BootROM itself. Before that even PowerPC-based Macintosh
computers were not even called "OldWorld" (so it must be "StoneAge"???).
According to
https://books.google.at/books?id=K8vUkpOXhN4C&pg=PA268&lpg=PA268#v=onepage&q&f=false
"Mac OS X Internals" by Amit Singh, Apple introduced Open Firmware AFTER
it switched from Motorola 68k to PowerPC. (Table 4-1, page 268:)
CPU Bus ROM Software ROM World
-------+-------+-----------------------+---------------+--------
68k NuBus Mac OS ROM (68k) -- --
PowerPC PCI System ROM (PPC) -- --
Mac OS ROM (68k)*
PowerPC PCI Open Firmware 1.x -- Old
Mac OS ROM
PowerPC PCI Open Firmware 2.x -- Old
Mac OS ROM
PowerPC PCI Open Firmware 3.x Mac OS ROM New
PowerPC PCI Open Firmware 4.x BootX (Mac OS X)New
*The PowerPC System ROM started the nanokernel on wich the 68k Mac OS
ROM ran largely unmodified (emulation)
My Problem is now that I cannot find when and with which model Apple
started using Open Firmware and is therefore part of the "OldWorld".
Another issue is that there were PowerPC upgrades to 68k-Macs, which
rules out Open Firmware altogether -- except if the firmware was part of
the CPU upgrade?!?
Here is a Quadra 700, originally a 68k-Mac, upgraded with a Daystar
Digital PowerPro 601/100MHz CPU and hence (with a little hacking)
capable of running PowerPC-only Mac OS 8.5:
http://www.asahi-net.or.jp/~gj3y-adc/old/Q700.html – referred to from
this guide: http://www.jagshouse.com/OS8.5On68KMacs.html
I don't really know if it makes a difference to Linux if it is run from
an OldWorld Mac featuring Open Firmware (1.x and 2.x) or a PowerPC-Mac
using the old Mac OS ROM code (and a PowerPC System ROM). And BootX
seems to be the name of a Linux loader (from Mac OS Classic)
http://mac.linux.be/content/apple-oldworld-computers as well as the name
that Apple chose for its own bootloader.
Whereas the NewWorld boot process is well documented
(http://mirror.informatimago.com/next/developer.apple.com/technotes/tn/tn1167.html),
the OldWorld as well as what was before (68k + PowerPC upgrades) based
booting isn't easy to find at all.
Does someone know more about these early PowerPC Macs?
Anyway, all the NewWorld suff should be included here:
http://www.everymac.com/systems/by_capability/mac-specs-by-machine-model-machine-id.html
And again sorry for the wrong information.
Linux User #330250
