Subject: Re: "esp" driver reorg proposal
To: None <tech-kern@NetBSD.ORG>
From: None <briggs@puma.macbsd.com>
List: tech-kern
Date: 01/26/1997 00:27:45
> > Looks good to me.  The mac uses this driver, too, btw.  In fact, the mac
> > will probably eventually need two different "flavors" of this driver--one
> > supporting DMA (for the 660av and 840av) and one that works w/o DMA (as
> > the current one does--most macs lack DMA controllers).
> 
> Why can't this be done via the existing DMA hooks?
> 
> On machines that do DMA, the DMA hooks would start DMA.  On machines
> which don't, the DMA hooks would just do the trasnfers...

If you look at the code, that's what I do.  I think that there were a
couple of changes that I had to make, though, in order to get it right
and minimally responsive (MacOS drivers still out-perform it by a factor
of about 4).  I tried, though, to keep the changes to a minimum.

Basically, I wanted to point out that the framework chosen should
support attaching devices with two different sets of hooks as well
as handling attachment of two devices with the same sets of hooks (with
a different register offset or private data of some sort).

-allen

-- 
              Allen Briggs - end killing - briggs@macbsd.com