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

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

On Mon, Mar 29, 2004 at 10:56:21PM +0100, Henning Makholm wrote:
> Scripsit Sven Luther <sven.luther@wanadoo.fr>
> > On Mon, Mar 29, 2004 at 12:52:12AM +0100, Henning Makholm wrote:
> 
> > > Huh? Is the bootsector use written in a kind of machine language that
> > > the regular as(1) for the architecture does not support? I thought
> > > that i386 was the only platform with *that* problem.
> 
> > I suppose that the boot sector may contain a bit more than the standard
> > elf or coff format. Not sure though.
> 
> In the absence of other evidence I'd assume that it's a short fixed
> header followed by raw machine code, designed to be loaded at some
> magic address and executed immediately. It *may* take a custom ld(1)
> script to produce quite the right setup, but after that, getting it
> into a usable format should be a simple matter - use objdump and a
> short piece of perl if everything else fails.

Notice that benh, the miboot author, told me that he was not really in
the clear how the hardware passes control to boot1, and thus didn't try
to make a clean reimplementation. So, altough i didn't look at it, it
may contain a bit more than just plain assembly output, checksums, and
other markers maybe.

> Google "macintosh boot block" turns up official Apple information that
> seems like it might be what you're looking for. (And which it would be
> OK to look at for a cleanroom implementor).

Ok, will have a look.

Friendly,

Sven Luther