Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S268000AbUIKJVu (ORCPT ); Sat, 11 Sep 2004 05:21:50 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S268037AbUIKJUx (ORCPT ); Sat, 11 Sep 2004 05:20:53 -0400 Received: from smtp-out.hotpop.com ([38.113.3.61]:42683 "EHLO smtp-out.hotpop.com") by vger.kernel.org with ESMTP id S268000AbUIKJUr (ORCPT ); Sat, 11 Sep 2004 05:20:47 -0400 From: "Antonino A. Daplas" Reply-To: adaplas@pol.net To: Dave Airlie , Michel =?iso-8859-1?q?D=E4nzer?= Subject: Re: radeon-pre-2 Date: Sat, 11 Sep 2004 17:20:38 +0800 User-Agent: KMail/1.5.4 Cc: Alan Cox , Jon Smirl , Felix =?iso-8859-1?q?K=FChling?= , DRI Devel , lkml , Linus Torvalds References: <1094873412.4838.49.camel@admin.tel.thor.asgaard.local> In-Reply-To: MIME-Version: 1.0 Content-Disposition: inline Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <200409111720.38477.adaplas@hotpop.com> X-HotPOP: ----------------------------------------------- Sent By HotPOP.com FREE Email Get your FREE POP email at www.HotPOP.com ----------------------------------------------- Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1961 Lines: 37 On Saturday 11 September 2004 13:19, Dave Airlie wrote: > The other thing I think some people are confusing is 2.4 fbdev and 2.6... > there is no console support in 2.6 fbdev drivers, it is all in the fbcon > stuff, so the fbdev drivers are only doing 2d mode setting and monitor > detection, some points I've considered are: Correct. fbdev is almost completely separate from fbcon. And you can actually rip out fbdev and place it anywhere you want. As long as fbcon has access to a pointer to framebuffer memory, and the characteristics of the display such as depth, pitch, etc, then the framebuffer console will work. Throw in a few functions, such as for buffer flipping, and fbcon will be happy. Hardware acceleration is entirely optional, and most drivers except for a few (such as vga16fb or amiga) can use the cfb_* drawing functions. There's also a recent change in the latest bk tree that changes the intialization order of the framebuffer system. Previously, fbcon triggers fbmem, then fbmem triggers each individual drivers. This method requires that a working fbdev is present, otherwise fbcon will fail (although you can do a con2fbmap later, or modprobe a driver). With the change, the order is reversed, driver->fbmem->fbcon. This change is probably significant because fbcon can wait until an active framebuffer activates. In theory, one can have a process (kernel or userland) change the video mode, then provide the in-kernel driver with the necessary information about the layout of the framebuffer. When this in-kernel driver gets the necessary information, it can trigger fbcon. This in-kernel driver need not know anything about the hardware (unless 2D acceleration is needed). Tony - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/