Hello Alexander,
Thanks for your answer!
So again, try loading the image somewhere else in RAM and let U-Boot do the copying to the correct place.
It's not obvious for me how to do it. Might you have any guide or faq?
[...]
### main_loop: bootcmd="movi read kernel 0 40008000;movi read rootfs 0
^^^^^^^^^^^^^^^^^^^^^^^^^^^
41000000 100000;bootm 40008000 41000000"
^^^^^^^^^^^^^^
Your bootmcd reads the kernel to 40008000 and then calls bootm to that address. Simple change those two places to, say, 40800000 by editing bootcmd. (Not knowing your system, I presume RAM starts at 4000,0000 and 4080,0000 then would be 8MiB after the beginning. U-Boot will copy the kernel to 4008000 so the kernel should not be bigger than 7.5MiB but the other snippets from your log say the kernel is ~3.2MiB, so this should be fine.
Cheers Detlev