From owner-freebsd-stable@FreeBSD.ORG Thu Apr 23 02:38:14 2009 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id C3311106566C; Thu, 23 Apr 2009 02:38:14 +0000 (UTC) (envelope-from npapke@acm.org) Received: from idcmail-mo2no.shaw.ca (idcmail-mo2no.shaw.ca [64.59.134.9]) by mx1.freebsd.org (Postfix) with ESMTP id 87AC98FC1B; Thu, 23 Apr 2009 02:38:13 +0000 (UTC) (envelope-from npapke@acm.org) Received: from pd6ml1no-ssvc.prod.shaw.ca ([10.0.153.160]) by pd5mo1no-svcs.prod.shaw.ca with ESMTP; 22 Apr 2009 20:38:13 -0600 X-Cloudmark-SP-Filtered: true X-Cloudmark-SP-Result: v=1.0 c=0 a=jNtHAGTFLQYKNJ66SW8A:9 a=RykZYj2P7OQlBzVqU3EA:7 a=tfIjyXs5kHmBABANflFp1aEVhFoA:4 a=nAPXUAfsBmEA:10 a=qufGkiYR55MA:10 a=frDgdN058V0A:10 Received: from s010600121729c74c.vc.shawcable.net (HELO proven.lan) ([24.85.241.34]) by pd6ml1no-dmz.prod.shaw.ca with ESMTP; 22 Apr 2009 20:38:12 -0600 Received: from proven.lan (localhost [127.0.0.1]) by proven.lan (8.14.3/8.14.3) with ESMTP id n3N2cC7n003807; Wed, 22 Apr 2009 19:38:12 -0700 (PDT) (envelope-from npapke@acm.org) Received: from localhost (localhost [[UNIX: localhost]]) by proven.lan (8.14.3/8.14.3/Submit) id n3N2cCO5003806; Wed, 22 Apr 2009 19:38:12 -0700 (PDT) (envelope-from npapke@acm.org) X-Authentication-Warning: proven.lan: npapke set sender to npapke@acm.org using -f From: Norbert Papke Organization: Archaeological Filing To: freebsd-stable@freebsd.org Date: Wed, 22 Apr 2009 19:38:11 -0700 User-Agent: KMail/1.9.10 References: <20090420152620.8f89edd5.lehmann@ans-netz.de> <200904221739.25097.npapke@acm.org> <1240448113.2142.11.camel@balrog.2hip.net> In-Reply-To: <1240448113.2142.11.camel@balrog.2hip.net> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200904221938.12129.npapke@acm.org> Cc: Robert Noland Subject: Re: dri + ATI: dramatic performance slowdown X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 23 Apr 2009 02:38:15 -0000 On April 22, 2009, Robert Noland wrote: > On Wed, 2009-04-22 at 17:39 -0700, Norbert Papke wrote: > > 0x0/0x100000000 BIOS write-back set-by-firmware active > > 0x100000000/0x40000000 BIOS write-back set-by-firmware active > > 0xc0000000/0x40000000 BIOS uncacheable set-by-firmware active > > MTRR is failing in many cases... It seems that your BIOS is doing what > both of my newer machines are doing and setting a global range to > write-back. I'm also guessing that 0xc0000000 is your framebuffer. Correct. The framebuffer starts at 0xd0000000, still covered by that last range. > We > aren't allowed to overlap either of these ranges with a write combined > region according to the specs. We would have to handle > splitting/merging regions which we don't currently do. I looked at this > just the other day, but it is reasonably complex to make that work right > and accommodate all of the merging/splitting of regions. > > We are allowed to use PAT on either of these types of regions to enable > write-combining. The drm code already does this for some allocations > that are not mapped to user space. The problem with PAT is that all > mappings of a given region need to have the same type and we don't > currently have any way to specify that for user space mappings. This is > fwiw, the last of Nvidia's feature requests as well. I've started > looking at it, but I have a lot of learning to do on the vm system > still. Thanks for taking the time to explain. Your posts are always very informative. I am learning quite a lot about the complexities involved. There is yet another thing I don't understand. With other graphics cards, including my G45 internal graphics adaptor, the /dev/agpgart device is created. I don't see this device with the Radeon card. Is this expected because it is not needed for PCIe? Cheers, -- Norbert Papke. npapke@acm.org