From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sylvain Meyer Subject: Re: Re: [patch 1/1] intelfb-voffset Date: Sat, 28 May 2005 11:02:50 +0200 Message-ID: <429833BA.6010104@worldonline.fr> References: <20050527220932.865B91C00449@mwinf0201.wanadoo.fr> <20050527155051.5e0fe177.akpm@osdl.org> Reply-To: linux-fbdev-devel@lists.sourceforge.net Mime-Version: 1.0 Content-Transfer-Encoding: quoted-printable Return-path: Received: from sc8-sf-mx1-b.sourceforge.net ([10.3.1.11] helo=sc8-sf-mx1.sourceforge.net) by sc8-sf-list1.sourceforge.net with esmtp (Exim 4.30) id 1DbxFH-0005sQ-HQ for linux-fbdev-devel@lists.sourceforge.net; Sat, 28 May 2005 02:04:39 -0700 Received: from smtp7.wanadoo.fr ([193.252.22.24]) by sc8-sf-mx1.sourceforge.net with esmtp (Exim 4.41) id 1DbxFF-00051q-Ll for linux-fbdev-devel@lists.sourceforge.net; Sat, 28 May 2005 02:04:39 -0700 Received: from me-wanadoo.net (unknown [127.0.0.1]) by mwinf0703.wanadoo.fr (SMTP Server) with ESMTP id 87BFD1000099 for ; Sat, 28 May 2005 11:04:30 +0200 (CEST) Received: from worldonline.fr (AGrenoble-152-1-49-140.w82-122.abo.wanadoo.fr [82.122.133.140]) by mwinf0703.wanadoo.fr (SMTP Server) with ESMTP id B7ADC1000098 for ; Sat, 28 May 2005 11:04:27 +0200 (CEST) Sender: linux-fbdev-devel-admin@lists.sourceforge.net Errors-To: linux-fbdev-devel-admin@lists.sourceforge.net List-Unsubscribe: , List-Id: List-Post: List-Help: List-Subscribe: , List-Archive: Content-Type: text/plain; charset="iso-8859-1"; format="flowed" To: linux-fbdev-devel@lists.sourceforge.net Andrew Morton a =E9crit: >sylvain.meyer@worldonline.fr wrote: > =20 > >>- Add voffset option to avoid conficts with Xorg i810 driver >> =20 >> > >Please provide more info. > >- How does it "avoid conflicts"? > It avoids conflicts in using memory allocations for framebuffer, hw=20 cursor and ring buffer which cannot be corrupted by the X driver. The=20 problem seems to be the exclusive use of BIOS calls in the X driver=20 instead of direct access to the hardware as in the intelfb driver. I=20 don't know what the BIOS do but i can see the corruption. In the X=20 driver, the BIOS is called to increase the stolen memory (part of the=20 aperture memory already allocated by the BIOS) if it is too small. I=20 think it's part of the problem. > >- How is the user to know that he needs to provide this module parameter= ? > The default parameter should be ok with default configuration of the=20 X driver. If VideoRam parameter is increased in xorg.conf, maybe a=20 different voffset should be passed to the linux kernel (now VideoRam=20 defaults to 32MB, voffset to 48 MB). Anyway, if i have spare time this week-end, i'll come with a small=20 doc. Just to to know, i borrowed this idea to the i810 driver, so the=20 parameter is already in use today. > >- Is it not possible to prevent these "conflicts" without the use of a > module parameter? > If i had the datasheet of the chips, maybe but now without lobbying=20 Intel and working blind, my answer is no. Sorry. >IOW: it's really a cop-out to require that the user know about some obsc= ure >module parameter to be able to amke their system work correctly. We >really, really want these things to "just work". > =20 > Yes, I share your concern but now I don't know how to do it. Sylvain ------------------------------------------------------- This SF.Net email is sponsored by Yahoo. Introducing Yahoo! Search Developer Network - Create apps using Yahoo! Search APIs Find out how you can build Yahoo! directly into your own Applications - visit http://developer.yahoo.net/?fr=offad-ysdn-ostg-q22005