From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Antonino A. Daplas" Subject: Re: Re: FB model basic issues (WAS: radeon, apertures & memory mapping) Date: Wed, 16 Mar 2005 07:37:01 +0800 Message-ID: <200503160737.04850.adaplas@hotpop.com> References: <1110696189.5787.100.camel@gaston> <20050315133628.GA16051@sci.fi> Reply-To: linux-fbdev-devel@lists.sourceforge.net Mime-Version: 1.0 Content-Transfer-Encoding: quoted-printable In-Reply-To: <20050315133628.GA16051@sci.fi> Content-Disposition: inline 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: Ville =?iso-8859-1?q?Syrj=E4l=E4?= , linux-fbdev-devel@lists.sourceforge.net Cc: Michel =?iso-8859-1?q?D=E4nzer?= , Benjamin Herrenschmidt , dri-devel@lists.sourceforge.net, xorg@lists.freedesktop.org, Jon Smirl On Tuesday 15 March 2005 21:36, Ville Syrj=E4l=E4 wrote: > On Tue, Mar 15, 2005 at 09:51:40AM +0100, Geert Uytterhoeven wrote: > > On Tue, 15 Mar 2005, Ville [iso-8859-1] Syrj??wrote: > > > If radeonfb will allocate the buffer for the second head from the top > > > of the memory users would basically have to guess it's location. > > > matroxfb simply cuts the memory in two pieces and allocates the buffe= rs > > > from the start of each piece. I don't really like that approach. Addi= ng > > > a simple byte_offset field to fb_var_screeninfo would solve the probl= em > > > quite nicely but I don't know if such API changes are acceptable at > > > this stage. > > > > You wouldn't have to guess its location, look at fix.smem_start. > > But how would someone mmap() the whole memory then? matroxfb already plays This is multi-head, right? That implies one fb per head. So, can't you do separate mmaps? fb0->fix.smem_start|len and fb1->fix.smem_start|len. Tony ------------------------------------------------------- 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