From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Winischhofer Subject: Re: Some questions Date: Tue, 11 Mar 2003 23:23:02 +0100 Sender: linux-fbdev-devel-admin@lists.sourceforge.net Message-ID: <3E6E61C6.2000503@winischhofer.net> References: <1047407816.1013.182.camel@localhost.localdomain> <3E6E4D9A.7060003@winischhofer.net> <1047419056.1100.26.camel@localhost.localdomain> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: Received: from static213-229-38-018.adsl.inode.at ([213.229.38.18] helo=home.winischhofer.net) by sc8-sf-list1.sourceforge.net with smtp (Exim 3.31-VA-mm2 #1 (Debian)) id 18ss9C-0001Bc-00 for ; Tue, 11 Mar 2003 14:22:59 -0800 Errors-To: linux-fbdev-devel-admin@lists.sourceforge.net List-Help: List-Post: List-Subscribe: , List-Id: List-Unsubscribe: , List-Archive: Content-Type: text/plain; charset="us-ascii"; format="flowed" To: Antonino Daplas Cc: James Simmons , Geert Uytterhoeven , Linux Fbdev development list Antonino Daplas wrote: >>>2. do not refresh unless var changed - fasted but can result in >>>corruption/crash if registers were changed behind the back of fbdev >> >>I think one can rely on tidyness of applications changing the registers. >>Like X does. > > > Unfortunately, this is what we are trying to prevent. X assumes that > the console is in text mode, so only registers that affect text mode are > restored. Frequently, cursor registers and bitmaps, as an example, are > not refreshed. There's probably more, ie accel engine, etc. That surprises me. The X drivers I looked at (quite a bunch) restore all registers (that need to be restored, that is) >>>3. selective refresh - do not refresh if switching between "trusted" >>>consoles, refresh if switching from "untrusted" consoles. >> > > I actually prefer #3, and I already have working code for this. We can > also make this driver switchable (ie, drivers that are not affected by X > can disable this, and only drivers that are affected such as the riva, > aty, radeon, etc can turn this on). What exactly is a "trusted" console? Thomas -- Thomas Winischhofer Vienna/Austria mailto:thomas@winischhofer.net *** http://www.winischhofer.net ------------------------------------------------------- This SF.net email is sponsored by:Crypto Challenge is now open! Get cracking and register here for some mind boggling fun and the chance of winning an Apple iPod: http://ads.sourceforge.net/cgi-bin/redirect.pl?thaw0031en