From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ville =?iso-8859-1?Q?Syrj=E4l=E4?= Subject: Re: [patch] radeonfb: FB_WAITFORVSYNC implementation Date: Sat, 12 Mar 2005 17:51:39 +0200 Message-ID: <20050312155139.GA28135@sci.fi> References: <1110636406.5997.86.camel@atlantis.netenviron.com> <9e473391050312073314dcb39f@mail.gmail.com> Reply-To: linux-fbdev-devel@lists.sourceforge.net Mime-Version: 1.0 Content-Transfer-Encoding: quoted-printable 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 1DA8u5-0003Zt-Fr for linux-fbdev-devel@lists.sourceforge.net; Sat, 12 Mar 2005 07:51:49 -0800 Received: from gw02.mail.saunalahti.fi ([195.197.172.116]) by sc8-sf-mx2.sourceforge.net with esmtp (Exim 4.41) id 1DA8u2-0004TU-V6 for linux-fbdev-devel@lists.sourceforge.net; Sat, 12 Mar 2005 07:51:49 -0800 Received: from kuori.saunalahti.fi (kuori.saunalahti.fi [195.197.175.23]) by gw02.mail.saunalahti.fi (Postfix) with ESMTP id D9583B9E9F for ; Sat, 12 Mar 2005 17:51:39 +0200 (EET) Content-Disposition: inline In-Reply-To: <9e473391050312073314dcb39f@mail.gmail.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="iso-8859-1" To: linux-fbdev-devel@lists.sourceforge.net On Sat, Mar 12, 2005 at 10:33:45AM -0500, Jon Smirl wrote: > 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. >=20 > 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. >=20 > See the "Who is stomping PCI config space?" thread in the x.org xserver= list. >=20 > Because of these issues WAITFORVSYNC in radeondb has to wait for > merged DRM/fbdev to be implemented. It's not a problem if one doesn't use X.Org/XFree86. Also this patch=20 should not affect X.Org/XFree86 users unless they manage to call the=20 FBIO_WAITFORVSYNC ioctl. matroxfb and atyfb both have similar interrupt=20 support and X can still be used with both. --=20 Ville Syrj=E4l=E4 syrjala@sci.fi http://www.sci.fi/~syrjala/ ------------------------------------------------------- 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