Re: Answer (Re: Cylinder limits jumper for drives over 32GB)

From: Andre Hedrick (andre@linux-ide.org)
Date: Wed Mar 29 2000 - 07:06:08 EST


On Tue, 28 Mar 2000, H. Peter Anvin wrote:

> Andre... what we're trying to figure out if there is a way to this
> *TRANSIENTLY*, so that a reset will set it back to the old value.
>
> However, if plugging in manual values in the BIOS works then that's
> probably the recommended way, unless there really is an easy way to work
> around.
>
> Remember... most hardware/firmware is broken. Part of what makes a good
> OS is to work with broken hardware without sacrificing working with
> properly working hardware. God knows I've messed lots with BIOS bugs.

Peter,

Please trust that I know the world is full of broken hardware, and even
if you follow the exact OEM directions for the hardware, it still can go
wrong. I see some of the worst night/day-mares in ATA hardware than
anyone can imagine.

There is only three possible solutions for the 05/14/99 (and older) AWARD
BIOS problem........

1) Users purchase an ADD-ON card that will handle the large drives.

2) Users issues a bogus geometry to the BIOS and we ignore it and use the
entire disk.

3) Users runs OEM capacity shrinking tool. Depend on Linux to issue
READ/SET_MAX_ADDRESS and update the values "soft" and not clobber the
"protected memory area". In principle, a reboot/power-cycle will revert
the capacity back to 32GB so that one may reboot with out a hang.

This is the preferred order in my book.

FYI, I am working with the ADD-ON card manufacturers to get them to
correct their BIOS code to prevent this problem.

Cheers,

Andre Hedrick
The Linux ATA/IDE guy

I only got wierded out because of potential partition fragmentation if any
goes wrong.

-
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/



This archive was generated by hypermail 2b29 : Fri Mar 31 2000 - 21:00:24 EST