Hi, On 10/01/2014 07:43 PM, Hendrik wrote: > 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.
Hmm, the only thing I can think of which may have caused this are the recent DRAM controller code cleanups which are in upstream u-boot and not in https://github.com/linux-sunxi/u-boot-sunxi Can you try copying these 2 files: arch/arm/cpu/armv7/sunxi/dram.c arch/arm/include/asm/arch-sunxi/dram.h >From https://github.com/linux-sunxi/u-boot-sunxi over into upstream u-boot, essentially reverting the DRAM cleanup patches, and see if that fixes things ? Regards, Hans _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
