Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262511AbVBBTpa (ORCPT ); Wed, 2 Feb 2005 14:45:30 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262712AbVBBTkp (ORCPT ); Wed, 2 Feb 2005 14:40:45 -0500 Received: from witte.sonytel.be ([80.88.33.193]:30357 "EHLO witte.sonytel.be") by vger.kernel.org with ESMTP id S262832AbVBBTjA (ORCPT ); Wed, 2 Feb 2005 14:39:00 -0500 Date: Wed, 2 Feb 2005 20:38:57 +0100 (MET) From: Geert Uytterhoeven To: Haakon Riiser cc: Linux kernel Subject: Re: Accelerated frame buffer functions In-Reply-To: <20050202174509.GA773@s> Message-ID: References: <20050202133108.GA2410@s> <20050202142155.GA2764@s> <1107357093.6191.53.camel@gonzales> <20050202154139.GA3267@s> <9e4733910502020825434a477@mail.gmail.com> <20050202174509.GA773@s> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2242 Lines: 48 On Wed, 2 Feb 2005, Haakon Riiser wrote: > > On Wed, 2 Feb 2005 16:41:39 +0100, Haakon Riiser > > wrote: > >> Thanks for the tip, I hadn't heard about it. I will take a look, > >> but only to see if it can show me the user space API of /dev/fb. > >> I don't need a general library that supports a bunch of different > >> graphics cards. I'm writing my own frame buffer driver for the > >> GX2 CPU, and I just want to know how to call the various functions > >> registered in struct fb_ops, so that I can test my code. I mean, > >> all those functions registered in fb_ops must be accessible > >> somehow; if they weren't, what purpose would they serve? > > > > You should look at writing a DRM driver. DRM implements the kernel > > interface to get 3D hardware running. It is a fully accelerated driver > > interface. They are located in drivers/char/drm > > Have the standard frame buffer drivers been abandoned, even > for devices that have no 3D acceleration (like the Geode GX2)? No. > GX2 is an integrated CPU/graphics chip for embedded systems. > We have third party applications that use the framebuffer device, > and I was hoping to make things faster by writing an accelerated > driver. The only thing I need answered is how to access fb_ops > from userspace. If that is impossible because all the framebuffer > code is leftover junk that no one uses anymore, or even /can/ > use anymore because the userspace interface is gone, please let > me know now so I don't have to waste any more time. mmap() the MMIO registers to userspace, and program the acceleration engine from userspace, like DirectFB (and XF*_FBDev 3.x for Matrox and Mach64) does. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds - 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/