@Fottes:

HW revision is not printed anywehere. But all HW revisions 21xx and 22xx are using same 2nd and NOLO images. So you can assume that you have one frequently used hw.

Cold flashing is needed only if bootloader was damaged, so when this command not working:

$ flasher-3.5 -i

How to cold flash, see post #9. If you really do not know your hw rev. use 2101. You cannot do anything with non working device with damaged bootloader...