PERFORCE change 33663 for review

[Eric Anholt]

On Thu, 2003-06-26 at 10:57, John Baldwin wrote:
> On 25-Jun-2003 Peter Wemm wrote:
> > http://perforce.freebsd.org/chv.cgi?CH=33663
> > 
> > Change 33663 by peter at peter_hammer on 2003/06/25 15:05:09
> > 
> >       Port sym to amd64
> 
> This is possibly not correct.  Do all hammer's support the P3+
> SFENCE and related instructions?  Even i386 should probably be
> using what bus_space_barrier() uses.  Heck, sym should probably
> just be using bus_space_barrier anyways.

It would sure be nice to have an MI call for the bus_space_barrier()
calls that don't need a bus_space_tag.  The DRM unfortunately doesn't
(and won't ever, I think) do bus_space, so we have to have
platform-specific ifdefs for read, write, and read/write barriers.

-- 
Eric Anholt                                eta at lclark.edu
http://people.freebsd.org/~anholt/         anholt at FreeBSD.org