Subject: Re: needs MI wdc changes to support macppc's wdc
To: Allen Briggs <briggs@canolog.ninthwonder.com>
From: Jason Thorpe <thorpej@nas.nasa.gov>
List: tech-kern
Date: 10/25/1998 16:22:57
On Sun, 25 Oct 1998 09:24:18 -0500 
 Allen Briggs <briggs@canolog.ninthwonder.com> wrote:

 > The mac68k wdc has non-contiguous offsets, too.  I think it's also every
 > 16 bytes.  I think that the cleanest solution is to make the bus_space*()
 > functions handle the register addressing, but I don't know if anyone has
 > measured any performance penalties that you might incur from doing so
 > (for the regions that don't need the offset modified).

Is that true for every obio device?  If not, then it shouldn't be done
in the space tag, but a "regmap" think like the dp8390 ethernet driver
uses would be more appropriate, used by ALL front-ends.

Jason R. Thorpe                                       thorpej@nas.nasa.gov
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