[ On Tue, January 5, 1999 at 10:49:43 (+0100), Manuel Bouyer wrote: ]
> Subject: Re: aix7xxx -- A Suggestion!
>
> On Jan 4, Matthew Jacob wrote
> > 
> > To be fair about it, the answer is 'no, you do not need CAm to support new
> > hardware'. It just makes it easier to port Justin's latest && greatest.
> 
> A compatible layer would be enouth for this.

I'm not so sure that's true.

My experience with CAM isn't very deep -- I've only read Justin's paper
and integrated his patches for CAM support in 2.2.7 a couple of times
and then used it on a couple of machines.  (And those were very
favourable experiences in so far as they went...)

I don't really know just how well defined the programming interface is
between the CAM infrastructure and the peripheral drivers.  I suspect
though that any compatability layer would in effect have to implement at
least some of the CAM architecture in order to provide a compatible
interface.

I also suspect that there's enough black magic in such an interface that
a compatability layer might introduce more problems than it solves.

I think if the "decision" is that CAM is "right" for NetBSD then it's
best to fully import the FreeBSD CAM support, and to do so sooner rather
than later, and to do so under the direction of the NetBSD "core" team.

If changes are found to be necessary in order to provide better
integration into NetBSD, whether they be necessary to support non-i386
architectures or whether they're simply deisred in order to do things in
"The NetBSD Way", then I would hope that those changes can be shared
between NetBSD and FreeBSD.

-- 
							Greg A. Woods

+1 416 218-0098      VE3TCP      <gwoods@acm.org>      <robohack!woods>
Planix, Inc. <woods@planix.com>; Secrets of the Weird <woods@weird.com>