Path: utzoo!utgpu!cunews!bnrgate!brtph3!brchh104!brchs1!bnr.ca!rice.edu!sun-spots-request
From: bmh@tigger.cs.unc.edu (Brad Hemminger)
Newsgroups: comp.sys.sun
Subject: Reserve part of regular memory to be outside of Unix?
Keywords: SunOS
Message-ID: <771@brchh104.bnr.ca>
Date: 11 Dec 90 20:55:27 GMT
Sender: news@brchh104.bnr.ca
Organization: Sun-Spots
Lines: 17
Approved: Sun-Spots@rice.edu
X-Sun-Spots-Digest: Volume 9, Issue 399, message 10
X-Note: Submissions: sun-spots@rice.edu, Admin: sun-spots-request@rice.edu

We have a project that uses a high speed communications card that will
talk directory to some memory on a VME card sitting on our Sun 4/370.  It
will cram data to/from the card at high speeds, and a software
driver/application will retrieve the data from the card.  Rather than
using this 'extra memory card' which costs $$, I was wondering if there
was a way to have partition a portion of the system memory so that the Sun
OS doesn't use it, and thus make it available for this communications
card's.  Thus if we could just tell the Sun to not use the last 10 Mbytes
of it's 32 Mbytes, and then have the driver be told the address of that 10
Mbytes instead of the addon card we could do the same thing without having
to get the addon card?  Can one do this?

Ps. I tried setting memsize with eeprom(8) to a lower value, but it had no
effect.

Brad Hemminger
bmh@cs.unc.edu