Build the PowerPC part of the NewWorld Mac ROM
Go to file
Elliot Nunn 7bee860e40 Reverse the CPU plugin mechanism
CPU plugins are code fragment resources that allow the NanoKernel to
perform CPU-specific functions, such as starting or stopping a processor
core or getting core temperature. They live in the Apple CPU Plugins
file. The Power Manager selects a plugin at boot (or doesn't), prepares
and holds it in memory, and registers it with the NanoKernel using
MPRegisterCpuPlugin(). The NanoKernel can then call any of the plugin's
entry points synchronously using its SIGP() function, which is also
exposed via the MPCpuPlugin() call. The plugin return path is tricky,
but involved the ReturnFromInterrupt trap instruction in the emulator
ROM code.

The CPU plugin calling convention is described in the SIGP comments. CPU
plugins operate in the blue address space, but with interrupts disabled
and supervisor mode on.

This code was reversed to get the Mac mini working. It is not clear how
the Power Manager determines CPU temperature when there are no CPU
registers to do this.
2018-03-09 20:30:37 +08:00
BuildResults Initial commit 2018-02-18 01:24:10 +08:00
Internal Reverse the CPU plugin mechanism 2018-03-09 20:30:37 +08:00
Linker Initial commit 2018-02-18 01:24:10 +08:00
NanoKernel Reverse the CPU plugin mechanism 2018-03-09 20:30:37 +08:00
.gitignore Initial commit 2018-02-18 01:24:10 +08:00
ConfigInfo.s Initial commit 2018-02-18 01:24:10 +08:00
EasyBuild Initial commit 2018-02-18 01:24:10 +08:00
Emulator.x Initial commit 2018-02-18 01:24:10 +08:00
MakeFile Initial commit 2018-02-18 01:24:10 +08:00
PPCExceptionTable.s Initial commit 2018-02-18 01:24:10 +08:00
README.md Initial commit 2018-02-18 01:24:10 +08:00
RomMondo.bin Initial commit 2018-02-18 01:24:10 +08:00
SetFileTypes.sh Initial commit 2018-02-18 01:24:10 +08:00

The PowerPC ROM for NewWorld Macs

This repo is part of the CDG5 project. It builds a 4 MB PowerPC Mac ROM by appending PowerPC code to a 68k Mac ROM (either the included dump, or one that you built yourself). The build result is a byte-perfect copy of the ROM inside the final "Mac OS ROM" release.

Fixing line endings

MPW requires old-style Mac line endings (CR), while Git works better with Unix line endings (LF). Git filters can be used to convert between the two. Files committed to the repo are "cleaned" (LF-ed), and then "smudged" (CR-ed) when they hit the working tree. After cloning, append these snippets to your Git config.

Append this to .git/config:

[filter "maclines"]
	clean = LC_CTYPE=C tr \\\\r \\\\n
	smudge = LC_CTYPE=C tr \\\\n \\\\r

Append this to .git/info/attributes:

* filter=maclines
*.* -filter
*.s filter=maclines
*.a filter=maclines
*.c filter=maclines
*.h filter=maclines

Finally, do a once-off "re-smudge":

rm -rf ../powermac-rom/*
git checkout .

Setting type and creator codes

Some MPW Tools require their input files to have the correct Mac OS file type, but Git does not save Mac OS type and creator codes. This shell script will give enough files a "TEXT" type to keep MPW happy.

sh SetFileTypes.sh

Building

This code is built with the Macintosh Programmer's Workshop (MPW), which runs on the Classic Mac OS. To satisfy the memory requirements of the build process, the MPW Shell should get a memory partition of at least 16 MB. Once you have MPW set up, the build process is not particularly fussy.

Not many computers run the Classic Mac OS any more. Here are a few workarounds:

  • Just find a Mac running Mac OS 7.5-9.2. (Not much fun if it's also your test machine.)
  • Use the Classic environment on a PowerPC Mac running Mac OS X 10.4 or earlier. (A small PowerBook or iBook is perfect.)
  • Use EMPW ("Emulated MPW"), a package of command-line tools, emulators and OS images that lets you run MPW commands straight from your macOS Terminal. This is my preferred solution.

Once MPW is set up, the build command is:

EasyBuild

Using EMPW, that's:

empw -b EasyBuild

The 4 MB image will be at BuildResults/PowerROM.

What's next?

On NewWorld Macs, this image is extracted into RAM from a "Mac OS ROM" file at boot. Use https://github.com/elliotnunn/newworld-rom to build such a file.