OK. I got serial console again.
As I said I damaged something important
My steps:
from recovery menu
Code:
Menu
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3. Load MMC0 over USB storage
4. Erase MMC0
I. Initialize Partition Table (fdisk) and format FAT
O. Format and overwrite FAT partition
E. Export FAT partition
U. Update using rootfs.img.gz or rootfs.img on FAT partition
Q. quit
Choose: 10
I chose "I"
Now my fat partition is clear and primary kernel can't mount rootfs
Is it THE END?
Log from console