From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jon Smirl Subject: Re: radeon, apertures & memory mapping Date: Sat, 12 Mar 2005 22:22:57 -0500 Message-ID: <9e47339105031219223e606a52@mail.gmail.com> References: <1110677744.19810.80.camel@gaston> Reply-To: linux-fbdev-devel@lists.sourceforge.net Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Received: from sc8-sf-mx1-b.sourceforge.net ([10.3.1.11] helo=sc8-sf-mx1.sourceforge.net) by sc8-sf-list1.sourceforge.net with esmtp (Exim 4.30) id 1DAKd0-0007k6-Ox for linux-fbdev-devel@lists.sourceforge.net; Sat, 12 Mar 2005 20:22:58 -0800 Received: from rproxy.gmail.com ([64.233.170.202]) by sc8-sf-mx1.sourceforge.net with esmtp (Exim 4.41) id 1DAKd0-0007tg-AW for linux-fbdev-devel@lists.sourceforge.net; Sat, 12 Mar 2005 20:22:58 -0800 Received: by rproxy.gmail.com with SMTP id z35so2147002rne for ; Sat, 12 Mar 2005 20:22:57 -0800 (PST) In-Reply-To: <1110677744.19810.80.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" To: Benjamin Herrenschmidt Cc: Linux Fbdev development list , dri-devel@lists.sourceforge.net, xorg@lists.freedesktop.org, Jon Smirl What about using the overlapped mode and dividing memory into four regions FB0 PCI visible free mem FB1 APER_SIZE non-visible free mem This way setting the mode on FB0 doesn't always bump into FB1. The DRM could do this: FB0 back0 depth0 aux0, etc PCI visible free mem - textures priority 2 aux1, etc depth1 back1 FB1 APER_SIZE non-visible free mem - textures priority 1 On Sun, 13 Mar 2005 12:35:43 +1100, Benjamin Herrenschmidt wrote: > I could maybe use a single ioremap though, that is use a single > aperture, and then switch the swapper on accesses. Though I should also > be careful not to end up conflicting with a userland process relying on > having the 2 separate aperture swappers stable for the mode on the 2 > separate framebuffer mappings... Like X would use fb0 while console > would use fb1 with a different swapper setting. That would blow up for > sure unless fbcon arbitrates accesses with X, which I don't see > happening right away. I suppose we'll have to consider both heads linked > as far as console ownership is concerned, at least for now, until the > kernel console subsystem is overhauled significantly. In the long term I was hoping to design thing such that the two heads can be used by two independent users, each could be running X or fbdev. A user space console implementation also makes a lot of sense in the multiuser case. User space console can be a DRI application instead of fbdev reducing the need to map. -- Jon Smirl jonsmirl@gmail.com ------------------------------------------------------- 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