From mboxrd@z Thu Jan 1 00:00:00 1970 From: Benjamin Herrenschmidt Subject: Re: FB model basic issues (WAS: radeon, apertures & memory mapping) Date: Wed, 16 Mar 2005 09:44:19 +1100 Message-ID: <1110926659.25201.11.camel@gaston> References: <1110677744.19810.80.camel@gaston> <9e47339105031219223e606a52@mail.gmail.com> <1110696189.5787.100.camel@gaston> <1110774523.4003.511.camel@localhost> <1110784327.5787.288.camel@gaston> <1110817205.4004.527.camel@localhost> <1110837171.5863.16.camel@gaston> <1110838356.4003.548.camel@localhost> <1110839873.5673.41.camel@gaston> <1110862777.4044.592.camel@localhost> <20050315060138.GA13064@sci.fi> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit In-Reply-To: <20050315060138.GA13064@sci.fi> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: xorg-bounces@lists.freedesktop.org Errors-To: xorg-bounces@lists.freedesktop.org Content-Type: text/plain; charset="us-ascii" To: Ville =?ISO-8859-1?Q?Syrj=E4l=E4?= Cc: Jon Smirl , Michel =?ISO-8859-1?Q?D=E4nzer?= , dri-devel@lists.sourceforge.net, Linux Fbdev development list , xorg@lists.freedesktop.org > DirectFB assumes all memory outside var.yres_virtual * fix.line_length is > preserved. A totally valid assumption in my opinion. Except that you can't know in advance how much fix.line_length will be. The "fix" isn't really "fixed". Different cards will have different requirements depending on the bit depth for example. On radeonfb, the line_length will vary due to alignment constraints related to the engine, or due to tiling, etc.... etc... So you basically don't know in advance what will be preserved... (And you can't, unless you start having all sort of card specific knowledge). Ben.