Re: Flash BIOS under linux

Peter Horton (pdh@colonel-panic.com)
Sat, 3 Apr 1999 01:59:23 +0100 (GMT)


On Thu, 1 Apr 1999, David Woodhouse wrote:

>
> djones2@glam.ac.uk said:
> > To the best of my knowledge this doesn't exist.
>
> It does. See http://www.freiburg.linux.de/~stepan/bios/
>
> > And as some BIOS manufacturers are very prohibitive about their
> > technology, it's unlikely that a generic tool will ever happen. You /
> > may/ convince some vendors to port to Linux, but I can't see that
> > happening.
>
> It's not too difficult to work it out. You know where the BIOS is mapped in
> memory because it's always at the same place (0xe0000 or 0xf0000?), you know
> what kind of flash chip they use because it's written on the top of the chip,
> and you know how to erase and write the flash because the manufacturer of the
> _flash_ publishes docs.
>

0xe0000 and 0xf0000 are usually shadow RAM, with the actual BIOS ROM up at
4GB. The ROM window is chipset controlled, and sometimes paged. Some
motherboards have *serious* hardware protection against re-Flashing the
BIOS.

P.

---
+---------------------------------------------------------------+
|  Peter Horton     -    software engineer    -     Linux 2.2.5 |
+---------------------------+-----------------------------------+
|  pdh@berserk.demon.co.uk  |  http://www.berserk.demon.co.uk   |
|  pdh@colonel-panic.com    |  http://www.colonel-panic.com     |
+---------------------------+-----------------------------------+

- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.rutgers.edu Please read the FAQ at http://www.tux.org/lkml/