Skip site navigation (1)Skip section navigation (2)
Date:      Fri, 29 May 1998 12:15:53 -0700
From:      Mike Smith <mike@smith.net.au>
To:        Joerg Schilling <schilling@fokus.gmd.de>
Cc:        mike@smith.net.au, freebsd-current@FreeBSD.ORG
Subject:   Re: cdrecord trouble on currnet / SCSI ABI test 
Message-ID:  <199805291915.MAA00509@dingo.cdrom.com>
In-Reply-To: Your message of "Fri, 29 May 1998 19:20:10 %2B0200." <199805291720.TAA15036@sherwood.gmd.de> 

next in thread | previous in thread | raw e-mail | index | archive | help
> >> The scg drvier which I wrote in 1986 is based on this interface and
> >> itself is the base for my portable SCSI user-level command transport
> >> system. It should be faily easy to make a CAM adoption layer for scg.
> 
> >It was.  The real problems with scg have to do with the lack of visible
> >documentation.  It is unclear how to do any sort of meaningful error
> >handling, or whether this should be managed at a lower level.  Again,
> >this is an issue I was postponing until I had established that
> >everything else was going to behave and the interface had stabilised.
> 
> The main problem with this documentation is that a hacker who wants to
> contribute code must have thorough knowledge on the SCSI protocol to
> understand what to do from reading simply a API doc.

Actually, they shouldn't.  Your scg stack passes SCSI commands down, and
expects them to be handled according to a set of rules.  The interface
shim has to provide a translation between those rules and the rules that
the host system advertises.

> For this reason, I prefer to have some ABI checker software.

Alan Turing.

> But for timeout tests not every CD-ROM drive is usable because the only
> idea I currently have to force a SCSI timeout is to do one very big
> SCSi-VERIFY on a disk with > 400MB data on it. This is because not all
> timeout implementations catch timeouts fast (< 1 minute).

Build a small board containing a 5380 and a microcontroller.  Write 
some minimal SCSI target software, and put a console on it.  

You could probably sell 5-10 of these to SCSI driver authors.

-- 
\\  Sometimes you're ahead,       \\  Mike Smith
\\  sometimes you're behind.      \\  mike@smith.net.au
\\  The race is long, and in the  \\  msmith@freebsd.org
\\  end it's only with yourself.  \\  msmith@cdrom.com



To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-current" in the body of the message



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199805291915.MAA00509>