Messages in this thread | | | Date | Wed, 2 Feb 2005 20:38:57 +0100 (MET) | From | Geert Uytterhoeven <> | Subject | Re: Accelerated frame buffer functions |
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On Wed, 2 Feb 2005, Haakon Riiser wrote: > > On Wed, 2 Feb 2005 16:41:39 +0100, Haakon Riiser > > <haakon.riiser@fys.uio.no> 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/
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