jantypas@hope.UUCP (John Antypas) (02/17/88)
Many thanks to the people who responded to my question on how to
access physical memory, but none of those ideas will work. I am
trying to write something at the driver level and thus, shared memory
won't work and I'm real leary about openning up kernel memory to just
anything. There IS a way to do this via normal system/kernel code. The
console driver has no problem -- I'd like to eventually have a console
driver which supports bitmapped graphics via just an extension of the
escape codes. (Of course this requires console source.... )
Anyone know how to get hold of physical memory in a driver? (I/O
physical memory NOT created by a kernel malloc().)
John Antypas -- Soft21 --21st Century Software:
UUCP: {garp, killer, pyramid, reed, sdcsvax!ucsd!ucrmath}!soft21!jantypas
Internet: jantypas%soft21.UUCP@{eddie.MIT.EDU, ucsd.UCSD.EDU}dave@viper.Lynx.MN.Org (David Messer) (02/24/88)
In article <122@ucrmath.UUCP> jantypas@soft21.UUCP (John Antypas) writes: >Anyone know how to get hold of physical memory in a driver? (I/O >physical memory NOT created by a kernel malloc().) > >John Antypas -- Soft21 --21st Century Software: > >UUCP: {garp, killer, pyramid, reed, sdcsvax!ucsd!ucrmath}!soft21!jantypas >Internet: jantypas%soft21.UUCP@{eddie.MIT.EDU, ucsd.UCSD.EDU} Yes, there are four routines included in the libraries to do this. They are described in linkkit/doc/link.doc. Here is there discription from that file: fpbyte (long physical address) fpword (long physical address) Get byte or word at physical address. Don't return anything. If there is no hardware at given address, behavior is unpredictable; garbage is usually returned. spbyte (long physical address, char data) spword (long physical address, int data) Set byte or word at physical address to data. It is very important to read link.doc before writing any kernal code, you will probably not be succesful otherwise. -- If you can't convince | David Messer - (dave@Lynx.MN.Org) them, confuse them. | Lynx Data Systems -- Harry S. Truman | | amdahl --!meccts!viper!dave | rutgers / Copyright 1987 David Messer -- All Rights Reserved This work may be freely copied. Any restrictions on redistribution of this work are prohibited.