From owner-freebsd-scsi  Tue Jul 16 12:20:37 1996
Return-Path: owner-freebsd-scsi
Received: (from root@localhost)
          by freefall.freebsd.org (8.7.5/8.7.3) id MAA27453
          for freebsd-scsi-outgoing; Tue, 16 Jul 1996 12:20:37 -0700 (PDT)
Received: from Sisyphos (Sisyphos.MI.Uni-Koeln.DE [134.95.212.10])
          by freefall.freebsd.org (8.7.5/8.7.3) with SMTP id MAA27428;
          Tue, 16 Jul 1996 12:20:31 -0700 (PDT)
Received: from x14.mi.uni-koeln.de (annexr2-47.slip.Uni-Koeln.DE) by Sisyphos with SMTP id AA22308
  (5.67b/IDA-1.5); Tue, 16 Jul 1996 21:20:17 +0200
Received: (from se@localhost) by x14.mi.uni-koeln.de (8.7.5/8.6.9) id VAA00899; Tue, 16 Jul 1996 21:20:08 +0200 (MET DST)
Date: Tue, 16 Jul 1996 21:20:08 +0200 (MET DST)
Message-Id: <199607161920.VAA00899@x14.mi.uni-koeln.de>
From: Stefan Esser <se@zpr.uni-koeln.de>
To: conta@alpo.casc.com (Alex Conta)
Cc: freebsd-scsi@freebsd.org, freebsd-hardware@freebsd.org
Subject: Adaptec 2940 PCI-SCSI on Compaq ProLinea 5100
In-Reply-To: <9607161820.AA12434@centime.cascade>
References: <9607161820.AA12434@centime.cascade>
Sender: owner-freebsd-scsi@freebsd.org
X-Loop: FreeBSD.org
Precedence: bulk

Alex Conta writes:
 > 
 > SCSI hardware/freebsd problem:
 > 
 > 1.
 > 
 > I have an Adaptec 2940 PCI-SCSI-2 adapter that works just fine under FreeBSD
 > 2.1 on a DEC Starion 960 PC (SCSI-2 hard disk drive + cd-rom).
 > 
 > The same adapter  works fine on a Compaq ProLinea 5100 (SCSI hard disk and 
 > cd-rom) under Windows 3.1, but it does not work when I try to install FreeBSD
 > from a CD-ROM distribution.
 > 
 > The installation fails because the adapter is not recognized. Booting with 
 > "-c" and setting manually the IRQ, Port Address, and other parameters didn't
 > help.

Please enter "-v" at the "Boot: " prompt 
and send me all numbers from the lines
starting with pcibus_setup or pcibus_check.

If it reports success in the pcibus_check
line, then I need any information about 
devices found on the PCI bus.

 > Known problem? Known solution?

Compaq caused lots of problems because of
their knowingly ignoring the PCI specs.
I once got a reply that it wouldn't matter,
since the BIOS and their drivers worked 
around the problems introduced this way.

But what they didn't care about was, that
the required workaround might break support
for other systems. They don't bother, since
they know their drivers are only used with
their machines. But we hardly want to have
a special FreeBSD version just for Compaq
machines ... :)

 > 2.
 > 
 > Any plans to add support for the AMD SCSI adapter that is embedded with 
 > Compaq DexPro 6200 XL?

There was a message from Tekram recently, who
seem to offer a SCSI board based on the same
chip and who seemed to be interested in having
it supported under FreeBSD. I sent them a reply,
but did not hear from them thereafter ...

Many people have asked for support of the AMD
SCSI chip. But since it is far less powerful 
than the NCR 53c810, which is available for 
some $70, nobody bothered to actually write
a driver for it ...

I understand that it might be good enough to
connect an external CDROM or tape ...

(It is a bus-master controller, but requires
the CPU to handle disconnect and that means 
that there are multiple interrupts per transfer
required and also that SCSI latencies are being
introduced which limit the SCSI throughput.
The NCR 53c810 as well as the Adaptec 2940 series 
offers a small CPU as part of the host adapter.)

Reagrds, STefan