I was able to extract the kernel configuration from the running android system and, after searching around, i found the same kernel version 3.0.35 (but obiviously without onyx patches).
I recompiled the kernel 1 milion of times but I am not able to see the console on the framebuffer (device mxcepdcfb), probably because I don't have the right device tree.
However i discovered that when the kernel panics I can access the internal iMX6 rom to replace uboot (but I will not do the test because this can fully brick the e-book reader)
I asked to onyx boox for kernel sources, device tree and some other informations, hope that they give a positive answer
