On Aug 11, 2004, at 3:44 PM, Sven Luther wrote:
On Wed, Aug 11, 2004 at 03:12:49PM -0400, Rick_Thomas wrote:
Here are a few practical suggestions:
Has anyone looked at "inside Macintosh" or some of the other early Mac
technical docs? I wonder if this code is, maybe, described there?
The real problem is that i am not a mac user, since i came from the
amiga
world, and am currently working for genesi, who produce the pegasos and
MorphOS, which is an amiga OS reimplementation. We have information
about the
boot block, but not the code in question. I know that it is mostly trap
instructions, and do some basic mac rom calls. If we were able to know
which
rom calls those are, and what they do, this would be enough for a
clean room
reimplementation.
I've been doing some research into this. In particular, I've been
looking at the "Monster drivers tech note" available on Apple's Tech
Support web site.
As I mentioned in another thread, calls to the OldWorld Mac ROM, for
anything other than a floppy, are actually calls to a patched/extended
image of the ROM -- patched and extended with whatever driver
information is needed to help the ROM code read from the device in
question on that particular type of Mac. Those patches/drivers are
licensed IP of Apple (or a third-party vendor if Apple doesn't directly
support booting from the device in question.)
The patches/drivers get installed on your hard disk by the Apple disk
partitioning utility (or a similar third-party utility) which is only
available as part of MacOS (or from the third party vendor).
It appears that re-writing the boot code part of miboot is really just
the tip of a very large iceberg. To be truly "free", you have to
provide a substitute for the patches and drivers.
It also appears that -- short of putting up with all the model specific
quirks of quik -- there's no way to avoid using the MacOS disk
partitioning utility at least once to install the driver/patch
partitions on a disk if you intend to boot Linux from that disk.
Enjoy!
Rick
PS -- I'll leave the question of what all this means for support of
Debian Sarge on OldWorld Macs to wiser heads than mine.
