Subject: Re: Snapshot report - 19 Feb tar_files
To: Alistair G. Crooks <>
From: Michael L. VanLoon -- Iowa State University <>
List: current-users
Date: 02/22/1994 11:02:06 (Alistair G. Crooks) writes:

>8.  The current list of supported SCSI boards looks like:
>bt742   eisa                    bt742a.c
>bt747   eisa (modified driver)  bt742a.c

>10.  Michael VanLoon's modified the bt742a.c driver for bt747s.  Look
>in the current-users mailing list archives if you missed it...

Actually, I'm not convinced this is confined to the 747.  From my
experience, the problem had to do with round-robin mailbox allocation
being the default in the newer ROM's.  This breaks the old bt driver
because it doesn't allocate in round-robin order, so after short (or
long under certain conditions) period of time, the driver is writing
mailboxes where the card doesn't expect them, and the card sees only
empty mailboxes where it's looking, so doesn't process any commands.

This behaviour should be seen on all new BusLogic cards from my
understanding, including the bt742a.  My driver is provided as a
universal upgrade for any BusLogic card under current.

A point worth making is that my driver is really only an upgrade of
certain newer capabilities (round-robin mailbox allocation and
page-aligned buffer allocation) to a very old driver.  I see it as an
interum fix.  The truly best situation is to get Julian's new SCSI
drivers into NetBSD-current, which have this bug fixed also.  I'll
port them over from FreeBSD-current if nobody else gets around to it.
But seeing as how it took two weeks to upgrade a very simple driver
file because of all my other committments, you can imagine how long
it'll be before I get around to finishing a project like that. ;-)
Anyone else who has more time to commit is welcome to integrate
Julian's latest SCSI drivers.


(P.S. Thanks Alistair for doing these reports...  They make a good
sounding board for things changing in current.)

    Michael L. VanLoon  --  --  gg.mlv@isumvs.bitnet
 Iowa State University of Science and Technology -- The way cool place to be!
   Project Vincent Systems Staff, Iowa State University Computation Center