Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!cornell!uw-beaver!rice!sun-spots-request
From: mcvax!aivru.sheffield.ac.uk!chris@uunet.uu.net (Chris Brown)
Newsgroups: comp.sys.sun
Subject: Re: accessing Sun physical memory
Keywords: SunOS
Message-ID: <8903220948.AA28578@aivru.uucp>
Date: 4 Apr 89 00:00:41 GMT
Sender: usenet@rice.edu
Organization: Sun-Spots
Lines: 16
Approved: Sun-Spots@rice.edu
Original-Date: Wed, 22 Mar 89 09:48:10 GMT
X-Sun-Spots-Digest: Volume 7, Issue 221, message 2 of 12

Mike Martys in v7n192:

> Another way is to manipulate the page map, mapping some part of the
> physical memory into a process's virtual space.  This looks good for
> performance, but the question is can this be done, and if so, can it be
> done easily (via some sort of Unix standard interface)?

This is precisely what mmap(2) does. Read the manual page. Also there is
more advice in the section "Mapping Devices without Device Drivers" in
Chapter 5 of the "Writing Device Drivers" manual. 

We use this a lot for frame buffers; it works fine. Mike - email me direct
if you want more info.

Chris Brown, A.I. Vision Research Unit, Sheffield University 
(chris@aivru.sheffield.ac.uk)