Path: utzoo!attcan!utgpu!cunews!bnrgate!brtph3!brchh104!brchs1!bnr.ca!rice.edu!sun-spots-request
From: hue@island.uu.net (Colonel Panic)
Newsgroups: comp.sys.sun
Subject: Re: SCSI device drivers
Keywords: Miscellaneous
Message-ID: <895@brchh104.bnr.ca>
Date: 19 Dec 90 09:21:31 GMT
Sender: news@brchh104.bnr.ca
Organization: Sun-Spots
Lines: 29
Approved: Sun-Spots@rice.edu
X-Refs:  Original: v9n399
X-Sun-Spots-Digest: Volume 9, Issue 406, message 17
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In article <753@brchh104.bnr.ca>, gaw@mercury.acc.com writes:
> I am trying to gather information concerning SCSI device drivers for SUN
> OS.  The standard manual that comes with SUN OS, "Writing Device Drivers"
> does not provide any in depth information into the interface to the SCSI
> bus.  It does reference two documents, "SCSI Implementation Guide" and
> "SCSA: SUN Common SCSI Architecture".  Has anyone out there written a
> device driver for a device on the SCSI bus and if so could they tell me if
> these manuals are worth obtaining?  Secondly are there any gotchas that
> are not documented anywhere?  How compatible is the SUN SCSI bus with that

Yes, you must get both of these.  Sun did the logical thing which is to
make the host adapter code separate from the device driver.  This way you
don't have to deal with managing the SCSI bus and can concentrate on
writing your driver.  The SCSA document describes the functions in the
SCSA library, the implementation guide describes other kernel support
functions and has an example driver.

The example sucks because it doesn't drive a real device, and assumes you
know all about non-SCSA device drivers (all they provide is xxslave(),
xxattach(), and xxstratgegy()), but they do have some useful code
fragments to show how you might handle errors and retrys.

Also, I am interested in starting a mailing list for people developing
device drivers that use SCSA.  I am not aware of one that already exists,
so if you are interested, send mail to me and I will set up a mailing
list.  I expect the names to be scsa-request@island.com for admin stuff,
and scsa@island.com for the actual mailing list, but it's not set up yet.

Jonathan Hue	Island Graphics Corp.	uunet!island!hue   hue@island.com