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Re: debian-installer now available in Ports



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


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