[LinuxBIOS] 1. Re: USB floppy boot (Peter Stuge)

Myles Watson myles at pel.cs.byu.edu
Mon Dec 10 18:03:03 CET 2007


On Dec 9, 2007 11:25 PM, Baski <kbaski at yahoo.com> wrote:
>
> Hello,
>
> On Sun, Dec 09, 2007 at 12:26:21AM -0800, Baski wrote:
> > I have a tiny kernel (not linux) and GRUB in a floppy disk. How can
> > I make it to boot using linuxbios?
>
> A few things need to be considered:
>
> * How does the kernel try to find the system information that is
>  usually exported by the BIOS in quite old-fashioned ways?
>  At a minimum, the kernel needs to know how much memory is in the
>  system. LB does not offer the same methods as a BIOS to learn this.
>
> * Does the kernel use other BIOS interrupt services? LB does not
>  offer any.
>
> * How large is your kernel?
>  If it can fit with LB in the boot flash (which is between 256kb and
>  1MB) you don't need the floppy at all.
> The kernel in experiment is very tiny in nascent stage,  about 50KB, and has
> only one functionality, printing out to serial port in loop.  Can I just put
> it in the flash instead of FILO?  Pl. advise.

Sure.  The easiest way is to make your kernel into an elf, then use it
as the payload for LinuxBIOS.

Myles




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