[Xorg-driver-geode] display mode with 800x480 on geode-2.11.1

[John Yoder]

The most basic problem I see is that there isn't a mode for your screen
in the resolution table for the Geode LX KFB. I expect the TFT is not
connected via VGA, so there would not be any DDC. If this is incorrect,
let me know. All that should be required is for you put the resolution
into lxfb_core.c. Verify that the dot clock corresponds to the PLL
frequencies in lx_ops.c before you recompile. Recompile the kernel, and
reboot. 

The performance for the LX KFB is not worse then the VESA KFB. Whether
you require any additional performance then the VEAS KFB is unknown. I
don't know what apps you are trying to have available. If it is Video
Playback, then the hardware YUV -> RGB conversion will most likely be
required. It is dependent on the resolution and codec of the clip.
Another consideration is whether the videos will need to be scaled or
not. for instance, playback to an external monitor. These options are
available in hardware, but not currently available in either the LX KFB
or VESA KFB. So this would be done in software. The code to enable these
features are available in a couple places including the Xorg geode
driver. Pulling code from one source and adding it to another is
possible but can be problematic. It can be done, just a significant bit
of work.

Since I have not worked with Android I am not sure how these modules are
related. From Chris Balls' response, they are related to the KFB not
drm. I am not certain what the outcome would be by selecting them. 

Best Regards,

John Yoder

On Fri, 2009-05-01 at 00:46 +0800, wan michael wrote:
> it often blinks after booting, not only at boot time. whether using
> vesa kfb 
> would be better than geode kfb since geode lx kfb is very basic and
> not feature rich.
> android uses opengl-es, not xorg server. like cfbcopyarea.ko,
> cfbfillrect.ko and so on,
> are they related to kfb or drm? selecting these modules can improve
> display even without
> hardware acceleration?
> 
>