From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261805AbTENKOZ (ORCPT ); Wed, 14 May 2003 06:14:25 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261808AbTENKOZ (ORCPT ); Wed, 14 May 2003 06:14:25 -0400 Received: from netline-be1.netline.ch ([195.141.226.32]:23560 "EHLO netline-be1.netline.ch") by vger.kernel.org with ESMTP id S261805AbTENKOW (ORCPT ); Wed, 14 May 2003 06:14:22 -0400 Subject: Re: Improved DRM support for cant_use_aperture platforms From: Michel =?ISO-8859-1?Q?D=E4nzer?= To: Ivan Kokshaysky Cc: davidm@hpl.hp.com, "Wiedemeier, Jeff" , Dave Jones , linux-kernel@vger.kernel.org, dri-devel@lists.sourceforge.net In-Reply-To: <20030514134141.A5170@jurassic.park.msu.ru> References: <1052690133.10752.176.camel@thor> <16063.60859.712283.537570@napali.hpl.hp.com> <1052768911.10752.268.camel@thor> <16064.453.497373.127754@napali.hpl.hp.com> <1052774487.10750.294.camel@thor> <16064.5964.342357.501507@napali.hpl.hp.com> <1052786080.10763.310.camel@thor> <16064.17852.647605.663544@napali.hpl.hp.com> <20030513173347.A25865@jurassic.park.msu.ru> <16065.6969.137647.391163@napali.hpl.hp.com> <20030514134141.A5170@jurassic.park.msu.ru> Content-Type: text/plain; charset=iso-8859-1 Organization: Debian, XFree86 Message-Id: <1052908024.18105.135.camel@thor> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.3.1.99 (Preview Release) Date: 14 May 2003 12:27:05 +0200 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Mit, 2003-05-14 at 11:41, Ivan Kokshaysky wrote: > On Tue, May 13, 2003 at 09:20:09AM -0700, David Mosberger wrote: > > > What's the nature of those "ugly and fragile" hacks? Are you saying > > that CPU accesses to AGP space aren't remapped in the "normal" (PC) > > way? Or is it something entirely different? > > Ok, you asked for it... :-) > As you know, Alpha architecture is entirely cache coherent > by design, i.e. there are no such things as non-cacheable mappings > or cache flushing in hardware. Native Alpha Titan/Marvel AGP controllers > are also cache coherent (kind of AGP extension of traditional > Alpha PCI IOMMU). > However, the "normal" PC AGP implementation isn't - this applies > to AMD-751/761 AGP controllers on Nautilus as well. > The AGP window on these chipsets is accessible by CPU *only* in the > system memory address space, i.e. it's always cacheable and thus > totally useless on Alpha. Set cant_use_aperture and use David's patch then? :) -- Earthling Michel Dänzer \ Debian (powerpc), XFree86 and DRI developer Software libre enthusiast \ http://svcs.affero.net/rm.php?r=daenzer