Thanks for offering to help.

After looking at this more to give you a clear picture of the uboot env and the kernel output, I found that I apparently got caught by the 'setenv x=y' issue instead of using 'setenv x y'.

So, I did not actually set the defaultdisplay variable, but instead set the variable defaultdisplay=lcd43 !!!

With the setenv deaultdisplay lcd43, you are right.  It works and the flicker I was seeing goes away.

Sorry for the red herring!


On Nov 8, 2009, at 8:17 PM, Steve Sakoman wrote:

On Sat, Nov 7, 2009 at 11:26 AM, Charles Woloszynski <> wrote:
Thanks for the info.  I tried this, but now the LCD is black for the entire boot.  No images at all.  

So, I tried to leave the defaultdisplay to dvi but used the new dvimode value.  With that, I got a screen with 'Overo' on it and a progress bar.  It flashes, but at least it looks like the screen is being used properly.

There is an error in the boot process that may cause this issue.  It does finally convert into a text screen with Angstrom image.  

So, I suggest that using just 

setenv dvimode 480x272MR-16@60

might be sufficient.

The fact that dvimode has any effect at all means that something else is wrong with your setup.

Setting defaultdisplay to lcd43 should cause the display subsystem to use the driver for the 4.3" display.  If everything is working right the resolution, timings, and sync polarities are fixed in the driver per the lcd spec.

It seems that the kernel is ignoring the defaultdisplay setting and continuing to use the dvi driver.  The mode you set "sort of" works - but trust me, the timings and sync polarities are wrong!

Please reply with a copy of your boot log and we can try to figure out what is wrong with your setup.  The change you made to dvimode is *not* the solution!


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