From owner-freebsd-current Fri Jul 30 2:39:58 1999 Delivered-To: freebsd-current@freebsd.org Received: from dingo.cdrom.com (castles548.castles.com [208.214.165.112]) by hub.freebsd.org (Postfix) with ESMTP id 9680C150A7 for ; Fri, 30 Jul 1999 02:39:56 -0700 (PDT) (envelope-from mike@dingo.cdrom.com) Received: from dingo.cdrom.com (localhost [127.0.0.1]) by dingo.cdrom.com (8.9.3/8.8.8) with ESMTP id CAA02191; Fri, 30 Jul 1999 02:34:36 -0700 (PDT) (envelope-from mike@dingo.cdrom.com) Message-Id: <199907300934.CAA02191@dingo.cdrom.com> X-Mailer: exmh version 2.0.2 2/24/98 To: Stephen Hocking-Senior Programmer PGS Tensor Perth Cc: current@freebsd.org Subject: Re: MTRR stuff In-reply-to: Your message of "Fri, 09 Jul 1999 10:32:37 +0800." <199907090232.KAA04002@ariadne.tensor.pgs.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Fri, 30 Jul 1999 02:34:34 -0700 From: Mike Smith Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG > For some video cards (to wit, the voodoo stuff), the MTRRs should be set up as > follows > > write-combining > +----------------------------------------------------------+ > +-------+ > uncacheable > > i.e. the two regions have the same starting area, but the small chunk for the > registers should be uncacheable. When I try to do this using memconf on my > K6-2, it spits the dummy. Is there a work around for this? The i686 MTRR implementation, at least, doesn't allow UC to overlap WC; only Write-back and uncached are allowed to overlap. I don't know what the K6's limitations are; you should talk to Brian Feldman about that. -- \\ The mind's the standard \\ Mike Smith \\ of the man. \\ msmith@freebsd.org \\ -- Joseph Merrick \\ msmith@cdrom.com To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message