Debian-installer, older hardware, boot loaders, miboot & amiboot & ..

[Sven Luther <sven.luther@wanadoo.fr>]

Hello,

I have been trying, with help from Jeremie Koenig, to get
debian-installer to work on oldworld powermacs, with the help of miboot
using boot floppies. Everything is ready for it, except one package
which is not yet in the archive, and which proved to be legally
nightmarish, so i have some serious doubts about it getting easily into
debian/main, which is needed since this would become a dependency for
building d-i.

I just had a long conversation with the upstream author, and understand
things better now.

The problematic file comes in a mac .sit format, is claimed to be GPL by
the author, and include the source in the above mentioned .sit (no idea
though, since i have no mac to look at them). There are various problems
though :

  1) to build those files, not only a mac system is needed, but also an
  older version of the code warrior compiler. => would mean contrib
  probably, but debian-installer is in main.

  2) a small file, the boot1 macos ressource, a 1K boot-sector to be
  copied to the floppy boot sector, is taken from the mac os system
  file. This is non-free, binary only, altough, well, the file in
  question only contains some ROM calls to initialize HFS, and load the
  boot2, open the mac os system file, and load boot2, which is provided
  by the GPL-free part of miboot mentioned above.

Well, i, and the upstream author too, think that it should be possible
to rewrite this small boot sector yourself. This would need good
oldworld pmac knowledge, which i don't have. It seems only a small part
of the 1K boot-sector is used. No idea what the source code of this
would look like. Jeremie, if it came to that, since you seem to have
some of the knowledge and the hardware, would you feel like
investigating this ? It is probable that Apple itself has not touched
said code since over 10 years or so.

Notice that the above is probably not much less free than the current
situation on most hardware, were we rely on non-free bioses to do the
actual booting and other tasks mentioned here. We don't ship said
non-free bios though (would this apply differently to someone shipping
boxes with linux preinstalled then ?).

Also, this pose the problem of various bootloaders for other, especially
older hardware. I know that at least the amiga/m68k and amiga/powerpc
variant depend on the amiboot/apusboot bootloader, which altough GPLed,
can only be built with the free gcc toolchain on amiga OS, probably
linking to some non-free system libraries there, not sure as those might
be part of the rom.

Do we have a response or a strategie for those cases, except the "give
instructions for the user to build the stuff himself from various URLS",
which was used, if i remember well, for miboot in boot-floppies. I think
amiboot and apusboot were shipped in binary form as part of the
boot-floppies source tarball, and in the resulting CDs also.

[ Please CC me or keep the debian-boot CCed, as i am not subscribed to
debian-legal, but am to debian-boot ]

Friendly,

Sven Luther