Tolino Vision bricked?

hi,
I got a Tolino Visio which is stuck at the Tolino logo. I can boot intro recovery but I cannot wipe and/or recovery the system, is failing with:

E:failed to verify whole-file signature
E:signature verification failed

I was able to connect to serial port and see the u-boot. I've attached the startup log from u-boot.

Any idea what I can do to restore it from SD card or from u-boot? One idea is to use some Kobo Aura tutorials to try to boot the os from external SD card, but no idea if it will work, and which image to restore on the card, and where to get them.

Attachment 199103


Attachment 199104

Attached Thumbnails

 

Attached Files

u-boot.txt (23.2 KB)