Subject: Re: config problem
To: Chris G Demetriou <Chris_G_Demetriou@ux2.sp.cs.cmu.edu>
From: Jason Thorpe <thorpej@nas.nasa.gov>
List: current-users
Date: 06/27/1996 14:07:58
On Thu, 27 Jun 1996 17:05:48 -0400
Chris G Demetriou <Chris_G_Demetriou@ux2.sp.cs.cmu.edu> wrote:
> (1) indirect configuration busses _can_ support 'cloning' devices at a
> minimal level, i.e. for unit number allocation purposes.
>
> At the very least, remember that cloning devices could be used to say
> "give me the next available unit number for this device," and that use
> of cloning device specs should not cause serious problems. e.g. you
> should be able to say (now that config supports multiple cloning
> devices of a single type):
>
> ed* at isa? port 0x280
> ed* at isa? port 0x300
Hmm, point taken. You're right, I just hadn't though of that... :-)
> (2) It's possible that it may make sense to have indirect config
> busses support 'real' cloning of devices, but that would require
> changes to the autoconfiguration code.
>
> Consider that, at least for most boards on indirect-config busses,
> there's a limited set of addresses which one of those boards can live
> at, e.g.:
>
> ed* at isa? port ?
Well, for some devices, this is certainly possible (c.f. the ep driver).
For others, well, it might be harder. The ep driver would probably work
as-is for the ISA cloning case.
-- save the ancient forests - http://www.bayarea.net/~thorpej/forest/ --
Jason R. Thorpe thorpej@nas.nasa.gov
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