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Date: Tue, 2 Apr 1996 20:40:15 +1000
From: Bruce Evans <bde@zeta.org.au>
Message-Id: <199604021040.UAA08815@godzilla.zeta.org.au>
To: julian@ref.tfs.com, phk@critter.tfs.com
Subject: Re: Changes to FreeBSD kernel to keep "green" drives on
Cc: Brett_Glass@ccgate.infoworld.com, bugs@freebsd.org,
        freebsd-hardware@freebsd.org, hackers@freebsd.org
Sender: owner-bugs@freebsd.org
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>Actually The thing I did was an utterly disgusting hack "sleep-hack" that
>assumes that if the disk went to sleep, it will wake up with a different
>geometry.  (workaround for a BIOS-bug).

Workaround for a FreeBSD bug?  I think the usual way out of full sleep
mode is to do a soft reset, and it's reasonable for that to set the
geometry to the default.  The driver may have worked without the hack
by getting confused enough to call wdunwedge() to wake up the drive
The hack probably made this more deterministic.

The driver now always uses the default geometry, so setting the geometry
after wakeup is probably a no-op.  However, IIRC the standard says to
always set it after resets.

Bruce