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[cc333]

Looks like things here have slowed down here a bit.

Here is a thread on the 68k MLA forum that is relevant: https://68kmla.org/forums/index.php?/topic/27613-picking-apart-the-newworld-rom/#entry294970

c

[nanopico]

Looks like things here have slowed down here a bit.

Here is a thread on the 68k MLA forum that is relevant: https://68kmla.org/forums/index.php?/topic/27613-picking-apart-the-newworld-rom/#entry294970

c

Yes I'm sorry about that.  All my work came to a grinding halt a little over a month ago and I've got myself back together enough (damn you brain) to start working on it again.  I just got a new development environment set up for easier testing. I'm hoping to have some sort of update soon.

[MacOS Plus]

Looks like things here have slowed down here a bit.

Here is a thread on the 68k MLA forum that is relevant: https://68kmla.org/forums/index.php?/topic/27613-picking-apart-the-newworld-rom/#entry294970

c

Yes I'm sorry about that.  All my work came to a grinding halt a little over a month ago and I've got myself back together enough (damn you brain) to start working on it again.  I just got a new development environment set up for easier testing. I'm hoping to have some sort of update soon.

  Glad to see you're up and running again!  Hopefully there's a few other brainiacs out there willing to help you with this work.  It would be more fair to you, and less 'precarious'.

[Protools5LEGuy]

Hi folks,

 

This post might meander a bit, because I'm sleepy, so I do apologise. I really wanted to post this now that I've had some success.

 

I have written a Python script to take apart and put back together a Mac OS ROM file (a NewWorld Toolbox image -- tbxi). Just this evening I've gotten my iMac G4 to boot from one of its reassembled images. This is a first step towards getting OS 9 to run on some seriously different PowerPC hardware (G4 mini, or even G5). Much of my information has been taken from the SheepShaver source, and from the occasional stray Technote. Here it is:

https://github.com/elliotnunn/cdg5

 

 I note a few things:

    The "parcels-based" tbxis used by ~9.1 onwards seem to be an attempt to offload hardware-specific work from the 4 MB ROM image to the Trampoline bootloader. The real work of my script is the extraction of the parcels into an XML data structure.
    The Trampoline ELF executable, as well as copying and modifying the Open Firmware device tree, sets up interrupts for the Nanokernel. This implies that the Northbridge and Southbridge are largely initialised before the Mac OS and drivers take over.
    Little has been done to reverse-engineer 4 MB PCI Power Mac ROMs (with the notable exception of the work of the SheepShaver devs). This is a shame, because at least the "resources" in the ROM are easily unpacked. I intend to do more work here.
    Open Firmware imposes a hard 4 MB limit on tbxis, so their contents *must* be compressed. What a pain.
    The two executables after the parcels blob in the tbxi file have a fixed offset (per file at least) and must be present to boot. It would be very helpful to be able to move them and give the parcels blob some breathing space, but this is not urgent because you can just remove unnecessary driver parcels.
    Anyone interested in the workings of the Mac OS Nanokernel should check out PowerMacInfo from the Multiprocessing SDK, which you can find at this mirror of Apple's FTP site: http://staticky.com/

Credit is due to nanopico of MacOS9Lives for his work on this thread, which introduced me to the insides of a tbxi: http://macos9lives.c....php?topic=2727

 

Cheers,

 

Elliot

[ELN]

Hi all,
I think I'll start posting here about my sleazy tbxi hacking. More interest! I have just gotten LZSS re-compression working (what a pain) so now I can rebuild a Mac OS ROM file from something more like scratch. In fact, my iMac just booted from such a file.
My repository is at: https://github.com/elliotnunn/cdg5
Best,
Elliot

[Protools5LEGuy]

What a team we have !

Welcome Elliot ! Thanks!

[nanopico]

Hi all,
I think I'll start posting here about my sleazy tbxi hacking. More interest! I have just gotten LZSS re-compression working (what a pain) so now I can rebuild a Mac OS ROM file from something more like scratch. In fact, my iMac just booted from such a file.
My repository is at: https://github.com/elliotnunn/cdg5
Best,
Elliot

This is awesome!  Using Elliots stuff here I poked through the parcels in there.   It appears to contain the toolbox rom, and some drivers required to exist (and would have in the old world roms) before the toolbox can start up.  the Northbridge driver being one of them. 

[ELN]

This is awesome!  Using Elliots stuff here I poked through the parcels in there.   It appears to contain the toolbox rom, and some drivers required to exist (and would have in the old world roms) before the toolbox can start up.  the Northbridge driver being one of them.

Neat!. Excuse if I take a while to get used to this quoting business.

I think it would be very useful to dump a list of the symbols imported and exported (roughly, the system functions called) by each PEF parcel blob (driver) so we have an idea of what role it plays (and doesn't!). We should be aware that there are dozens more PEFs in the 4 MB image itself. (I might write a script to extract these.) Indeed, based on one technote and the fact that "parcels" appeared quite late in the game, I suspect that the moving of things out of the 4 MB image was a work in progress.

I actually think that the Trampoline is doing the hardware init that we're really interested in. It certainly seems to be interested in interrupts.

By the way, anyone got a G4 mini?

[DieHard]

Wow...Mac OS 9.5 is obviously on the way before 2017! 

I get so pumped up reading this thread I think the wife is going to get lucky tonight.  You guys are Fu%#$ing amazing.

[nanopico]

Yeah Elliot and I are working together on this. 
I actually have this crazy idea now that we can probably get some level of booting on the mac mini and xserve g4's with some creative complicated manual open firmware adjustments.  Still probably won't boot very far, but it's entirely possible.  If this idea works then updating the ROM so those hacks aren't required would be very very possible.

[MacTron]

Yeah Elliot and I are working together on this. 
I actually have this crazy idea now that we can probably get some level of booting on the mac mini and xserve g4's with some creative complicated manual open firmware adjustments.  Still probably won't boot very far, but it's entirely possible.

Booting the xServe with Mac Os 9 may be a great conquest. But while as it have very similar parts to a MDD, it have other very different components, wich can difficult the Mac Os 9 booting.
Here we have an early  draft of this project:

http://macos9lives.com/smforum/index.php/topic,1964.msg10740.html#msg10740

[nanopico]

Yeah Elliot and I are working together on this. 
I actually have this crazy idea now that we can probably get some level of booting on the mac mini and xserve g4's with some creative complicated manual open firmware adjustments.  Still probably won't boot very far, but it's entirely possible.

Booting the xServe with Mac Os 9 may be a great conquest. But while as it have very similar parts to a MDD, it have other very different components, wich can difficult the Mac Os 9 booting.
Here we have an early  draft of this project:

http://macos9lives.com/smforum/index.php/topic,1964.msg10740.html#msg10740

I like a challenge, even if it is unrealistic.

[MacOS Plus]

Yeah Elliot and I are working together on this. 
I actually have this crazy idea now that we can probably get some level of booting on the mac mini and xserve g4's with some creative complicated manual open firmware adjustments.  Still probably won't boot very far, but it's entirely possible.

Booting the xServe with Mac Os 9 may be a great conquest. But while as it have very similar parts to a MDD, it have other very different components, wich can difficult the Mac Os 9 booting.
Here we have an early  draft of this project:

http://macos9lives.com/smforum/index.php/topic,1964.msg10740.html#msg10740

I like a challenge, even if it is unrealistic.

...  And I have a spare xServe Rev 1 lying around doing nothing.  If I can get OS 9 working on it then I'll have an excuse to actually make use of it!  I even have the substitute AGP riser available so I have more choice of video cards.

  I suppose, in the end, anything learned in success or failure on the 'less-realistic' machines will still go a long way towards achieving full function of the other machines we're much closer on.