Subject: Re: Any way to get virtual addr from pci_mapreg_map()?
To: Ignatios Souvatzis <ignatios@cs.uni-bonn.de>
From: Scott Reynolds <scottr@Plexus.COM>
List: tech-kern
Date: 08/12/1997 15:18:45
On Tue, 12 Aug 1997, Ignatios Souvatzis wrote:

> khym@bga.com (Dave Huang) writes:
> 
> > [...]
> > so I'm wondering if it's possible to get a virtual address out of the
> > tag and handle that I can assign to a pointer.
> 
> You don't want to do this.

To put it another way, this is an abstraction violation.  To do this
portably, you need to use bus_space_{read,write}.  As you point out, this
may be less clear, but it is necessary.  Remember that a tag/handle pair
does not necessarily imply any particular address space, so an MI driver
can't assume that it does.

--scott