Philosophical question...

[Matthew Sullivan]

Hi,

Charles Esson wrote:

> Matthew Sullivan wrote:
>
> -[snip]-

> > >
> > > So a bios has to load a OS ( application),
> >
> > Not so...
>
> Why not, to a boot loader a OS  is nothing more than an application. If you look at open
> boot you will see there are options to leave the loader in memory  with open boot code
> allocating memory to the OS on request, and dealing with the OS's I/O. It seem like a
> logical thing to to. The OS provides the API the user applications expect. The BIOS
> provides a hardware independent layer for the OS. Under NT it is the HAL, under Apple and
> sun it's open boot.
>
> Once upon a time the IBM pc double boot made sense. Today with flash being what it is, it
> makes no sense.
>

I think we maybe at cross purposes here.  I was refering to the 2 parts of the BIOS, the main
part and the failsafe.

My reference was the the failsafe, a small peice of code to load a BIOS image eg: from
floppy, if the main BIOS code is corrupt, not present.  This code would be 'protected' from
being over written by normal BIOS installation and only serves the purpose to ensure that
someone updating their BIOS to a different config will be ensureed that theyu will always
beable to 'repair' any possible 'damage' with out the need for the pocket EPROM/FLASH
programmer ;-)



>
> >
> >
> > > and has to have network code so it can
> > > load from the logical location.
> >
> > This shouldn't be too dificult anyhow, if you have a netcard boot prom, the code from
> > that could be used to get a config/boot file,
>
> You have made a large assumption about the boot hardware, not a wise thing for a bios to
> do.
>

Not a large assumption, a net card with a boot rom will get a boot image, we can exploit
that...  If it doesn't have a boot rom, then it's not used.. Look at today's AMI/AWARD BIOS's
for the example of what I mean...... ;-)

>
> > and in the 'safe' code mode, a flash
> > image be collected instead of the normal boot code.
>
> Loading the OS is a minor issue, providing a device independent layer for the OS that is
> the big one..

Cross purposes I think...

>
> > Floppy disk support should be
> > used, you might find that the 'safe' image with IDE code will get to big to have it in
> > a failsafe area.
>
> A few more years and floppy disks will be something we remember. I won't remember them
> fondly, too many boot block viruses, and failed floppies for me to  have happy memories.

I hope not, I know they are getting scarser, but unrelyable, slow, as they maybe, but they do
work, and the hardware is pretty much standard... (IF & Size).  Code for initializing a
floppy controller & reading a disk is very small considering the same code required for IDE
drives.. (Remember there are an aweful lot of chipsets out there, and the failsafe code
doesn't want to be hardware dependant ie, it needs to be the same code for everyone, so it is
slick stable, and works cross platform, then it only needs to be programmed once - you won't
get a second chance with it - if it works you could install anything into your flash
afterwards, and providing you didn't remove that initial check/backup code, you'll still be
able to boot an image from a device, whether it be floppy or net supplied.....)

Just my thoughts....

Yours

Matthew
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