Messages in this thread | | | Date | Thu, 11 May 2006 12:26:06 -0400 | Subject | Re: geode sc1200 2D graphics acceleration | From | (Lennart Sorensen) |
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On Thu, May 11, 2006 at 03:26:14PM +0200, Carlos Ojea Castro wrote: > I am drawing some graphics (a group of lines) using DirectFb in a > geode sc1200 (kernel 2.4). > I discovered that when I disable 2D hardware acceleration (by changing > '/root/.directfbrc' and '/etc/directfbrc') it is FASTER than drawing > with 2D hardware acceleration enabled. > > Can't figure why. Any ideas?
Could it be related to the video on the sc1200 being emulated by SMI (at least as far as I understand things)? Perhaps the acceleration simply makes the BIOS/SMI stuff go do all the work, while with no acceleration, the kernel writes all the bits directly, which is more efficient than the BIOS/SMI emulation? I think that is how the VSA stuff works on those systems at least. I have VGA disabled on the boards I use here, so all I know is that the video is very slow on these systems when I tried it once, and since I don't have a use for it, I disabled it.
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