Subject: Re: mmap'ing framebuffer memory in MI drivers...
To: None <eeh@netbsd.org>
From: Jason Thorpe <thorpej@nas.nasa.gov>
List: tech-kern
Date: 03/05/1999 19:14:01
On Fri, 5 Mar 1999 18:50:07 -0800 (PST)
"Eduardo E. Horvath" <eeh@one-o.com> wrote:
> Hold it -- why is (*d_mmap)() returning anything? Why doesn't it call
> pmap_enter() or the equivalent (or bus_device_whozit() that eventually
> works its way down to pmap_enter()) in the first place, return success or
> failure, and be done with it? That way ports that need to can create an
> alternative MD entry point into pmap that can be passed all this extra
> meta-info and we don't need to encode it into the physical address and
> check for it every time pmap_enter() is called.
...because, for one, the first N times it's called, you're not entering
any mappings at all... You're just checking that the mapping request is
valid.
Take a look at udv_fault() for how the mappings are actually entered.
-- Jason R. Thorpe <thorpej@nas.nasa.gov>