From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kyle Moffett Subject: Re: Regression: radeonfb: No synchronisation on CRT with linux-2.6.13-rc5 Date: Sun, 7 Aug 2005 21:13:54 -0400 Message-ID: <96358AEB-784F-444E-A0BA-04AD920284B3@mac.com> References: <1123195493.30257.75.camel@gaston> <1123401069.30257.102.camel@gaston> <3EF2003B-12DF-4EBB-B304-59614AEFAA09@mac.com> <1123431219.30257.115.camel@gaston> Reply-To: linux-fbdev-devel@lists.sourceforge.net Mime-Version: 1.0 (Apple Message framework v733) Content-Transfer-Encoding: 7bit Return-path: Received: from sc8-sf-mx1-b.sourceforge.net ([10.3.1.91] helo=mail.sourceforge.net) by sc8-sf-list1.sourceforge.net with esmtp (Exim 4.30) id 1E1wDM-000565-Uj for linux-fbdev-devel@lists.sourceforge.net; Sun, 07 Aug 2005 18:14:04 -0700 Received: from smtpout.mac.com ([17.250.248.89]) by mail.sourceforge.net with esmtp (Exim 4.44) id 1E1wDL-0001HW-M7 for linux-fbdev-devel@lists.sourceforge.net; Sun, 07 Aug 2005 18:14:04 -0700 In-Reply-To: <1123431219.30257.115.camel@gaston> 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"; delsp="yes"; format="flowed" To: Benjamin Herrenschmidt Cc: Bodo Eggert <7eggert@gmx.de>, LKML , linux-fbdev-devel@lists.sourceforge.net On Aug 7, 2005, at 12:13:38, Benjamin Herrenschmidt wrote: >> I've got an LCD, and on mine >> it looks like every third pixel-line gets shifted about 32-64 >> pixels to >> the left, and they move with display refresh. My guess is that >> something is interrupting radeonfb during a critical time in display >> syncing and forcing the video card to wait too far into the next line >> before sending pixels. > > radeonfb is mostly inactive after it has setup the framebuffer and > unless you actually draw something, in which case, accel code is > called. > > _However_ there is an unrelated problem with some panels, including > some > of the 17": The panel doesn't always "sync" properly. This seem to be > related to some subtle timing issue in the LVDS code but I don't know > exactly what yet. You can usually get it back by repeately turning the > backlight all the way down (which shuts the panel off) and back up > until > it "catches". Hmm. This doesn't really fit as my issues are very reproducible. The behaviour under stock Debian 2.6.8 is identical during reboots and after fblevel 0 ; sleep X ; fblevel 15. Likewise, stock 2.6.11, 2.6.12.4, and 2.6.13-rc5, although I'm just getting back to testing things. Cheers, Kyle Moffett -- There are two ways of constructing a software design. One way is to make it so simple that there are obviously no deficiencies. And the other way is to make it so complicated that there are no obvious deficiencies. The first method is far more difficult. -- C.A.R. Hoare ------------------------------------------------------- SF.Net email is Sponsored by the Better Software Conference & EXPO September 19-22, 2005 * San Francisco, CA * Development Lifecycle Practices Agile & Plan-Driven Development * Managing Projects & Teams * Testing & QA Security * Process Improvement & Measurement * http://www.sqe.com/bsce5sf