From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jon Smirl Subject: Re: [patch] radeonfb: FB_WAITFORVSYNC implementation Date: Sat, 12 Mar 2005 10:33:45 -0500 Message-ID: <9e473391050312073314dcb39f@mail.gmail.com> References: <1110636406.5997.86.camel@atlantis.netenviron.com> Reply-To: linux-fbdev-devel@lists.sourceforge.net Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Received: from sc8-sf-mx2-b.sourceforge.net ([10.3.1.12] helo=sc8-sf-mx2.sourceforge.net) by sc8-sf-list1.sourceforge.net with esmtp (Exim 4.30) id 1DA8cp-0002b2-If for linux-fbdev-devel@lists.sourceforge.net; Sat, 12 Mar 2005 07:33:59 -0800 Received: from rproxy.gmail.com ([64.233.170.204]) by sc8-sf-mx2.sourceforge.net with esmtp (Exim 4.41) id 1DA8co-00037o-69 for linux-fbdev-devel@lists.sourceforge.net; Sat, 12 Mar 2005 07:33:59 -0800 Received: by rproxy.gmail.com with SMTP id z35so1839284rne for ; Sat, 12 Mar 2005 07:33:45 -0800 (PST) In-Reply-To: <1110636406.5997.86.camel@atlantis.netenviron.com> 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="us-ascii" To: linux-fbdev-devel@lists.sourceforge.net You can't do this without coordination from X and DRM. If either of those are in use you will lock the machine with this patch. DRM also implements WAITFORVSYNC as well as other interrupts. If you clear the ISR DRM is going to stop working. X is a bigger problem. If the radeonfb adapter is not the primary X adapter, X is going to disable its IO/MEM access at the PCI level on VT switch. Your radeonfb will then take an interrupt and not be able to acknowledge it. This results in an interrupt loop and you rebooting your machine. See the "Who is stomping PCI config space?" thread in the x.org xserver list. Because of these issues WAITFORVSYNC in radeondb has to wait for merged DRM/fbdev to be implemented. -- Jon Smirl jonsmirl@gmail.com ------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click