From owner-freebsd-hackers  Sun Dec 14 18:56:37 1997
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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 CST."
             <199712150045.SAA14933@bob.scl.ameslab.gov> 
Date: Sun, 14 Dec 1997 19:54:28 -0700
From: "Justin T. Gibbs" <gibbs@plutotech.com>
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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.
>
>Chris

Although the bus.h stuff I did for CAM is taken pretty much verbatum
from NetBSD, I did not implement bus DMA in the same fashion.  The
interface was changed slightly to make it more space efficient.

--
Justin