I have always been using the sunxi u-boot from 'https://github.com/linux-sunxi/u-boot-sunxi' and that works fine, but now I want to boot the kernel from USB. That is not possible in that u-boot branch. Therefore I switched to the latest U-Boot 'git://git.denx.de/u-boot.git' for the Olimex Allwinner A10 Lime as this one does have a working USB mass storage implementation.
But when the kernel and root filesystem is booted and my application (using DirectFB) starts, the LCD screen is flickering between a correct image and an incorrect image as if sometimes random image data is displayed to the screen. Although it looks more like a clock or timing issue because the colors of the faulty screen resemble the colors of the correct screen. Also: when the cpu is inactive the screen is more or less ok but when doing a lot of work the screen starts to flicker. Then it is stable for a while and after some time it starts flickering again.
I am using the exact same kernel, root filesystem, U-boot environment, SD-card and 'script.bin' (which defines the hardware layout, I am not using a device tree file). The only difference is the version (and origin) of U-boot.
Can anybody shine some light on this? Maybe Hans de Goede? I have seen his name pop-up a lot of times with the Sunxi branch.
Regards, Hendrik