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To: Chris Csanady <ccsanady@bob.scl.ameslab.gov>
cc: "Justin T. Gibbs" <gibbs@plutotech.com>,
        John-Mark Gurney <gurney_j@resnet.uoregon.edu>, hackers@freebsd.org
Subject: Re: Bus/Processor specific I/O methods - was Re: Beginning SPARC port 
In-reply-to: Your message of "Sun, 14 Dec 1997 18:45:56 MDT."
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Date: Mon, 15 Dec 1997 11:45:22 +1030
From: Mike Smith <mike@smith.net.au>
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> 
> FWIW, NetBSD has a couple of nice man pages on their bus stuff.  See
> bus_space(9) and bus_dma(9).  It looks like a well abstracted interface,
> and works on several architectures.  We really should be looking at ways
> to make the BSD's more similar whenever possible.  Making the drivers
> more portable would especially be nice.. so I think that this issue
> definately deserves more thought.

The NetBSD 'bus.h' interface has had a lot of time to stabilise, and 
plenty of performance-sensitive pounding.  For all its conceptual 
difficulty, it *does* appear to be the best way to go.

(No insult intended, JMG!)

mike