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To: filo@yahoo-inc.com
cc: freebsd-hackers@freebsd.org
Subject: Re: biosboot/start.S needs fix for Intel AL440LX motherboard 
In-reply-to: Your message of "Thu, 16 Oct 1997 03:48:28 MST."
             <199710161048.DAA27096@ns2.yahoo.com> 
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Date: Fri, 17 Oct 1997 09:41:09 +0930
From: Mike Smith <mike@smith.net.au>
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> The latest BIOS from Intel for their AL440LX board does not pass the
> drive number in %dl as biosboot/start.S assumes (instead %dl is set to
> 0).  The end result is that you cannot boot from a harddrive if you're
> not using slices (a "Read error" occurs after the BIOS hands over
> control).  Booting from floppy works fine and using slices with bteasy
> works as well.

Unpleasant.  How are you supposed to differentiate between booting from 
a harddisk (0x8?) and a floppy (0x0?) ?

> Forcing %dl to $0x80 (which is what bteasy appears to do) solves the
> problem for me.  I assume the real solution is a bit more complex than
> this.  I suppose this could be due to some weird BIOS setting, but I
> think I pretty much tried everything.  This board will be popular, so
> would be nice to get this fixed.

Unless Intel are angling for compatability with some other standard, I 
think the correct fix will be a BIOS upgrade.  If they are, it'd be 
handy to know which one, so that we can detect and support it.

Forcing %dl to 0x80 obviously breaks using the same start.s for both 
harddisk and floppy booting.

mike