Adam Agnew <[EMAIL PROTECTED]> writes:

> > > That's the idea. Eric is pushing for a scheme where by we would chain-load
> > > to the first sector of a partition. I agree that's a good idea. But we'd
> > > need to put another bootloader with polled ide and no BIOS dependance
> >
> > How do you place such a bootloader ?  As an addition to the BIOS or as an
> > replacement, so that the kernel can do the complete initialisation ?
> 
> ?... I think there's a misunderstanding. In such a scheme, there would be
> a VERY minimal bootloader on the flash with linuxbios. It would then load
> a LARGER bootloader which lives on your hard drive, just like LILO does.

My thinking is the minimal bootloader would find the an ELF header
in the first couple sectors of the drive.  The ELF header would specify
where to find the rest of the image.  For supporting arbitrary locations
above 4GB we'd need to support 64 bit ELF on i386, but that is
straightforward.  And as easy to setup as lilo.

So for minimal systems that should be all we'd need.  And then for
systems where you want an interactive all singing all dancing
bootloader.  We can load the linux kernel + an initrd with kexec
support that supports every filesystem, and every device we care about
as a second stage bootloader.

I think there is a lot the original x86 BIOS got right, it was simple
and it did simple minimal things.  The only thing I object to is the
need to support BIOS calls.  On the PC platform enough programmers didn't
use the BIOS calls for them to provice hardware independance.  And we saw
cost decreases because software directly accessed the hardware and people
had to be compatible.

I like simple and stupid bioses because there are fewer opportunities
for bugs.

Eric

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