BTW a good axample that this code is not ideal

# read hardware version from EEPROM
tpi_info hw_version tpi_hw_version

setenv fit_boot_args "${loadaddr}#config-${tpi_hw_version:-v2.4.0}"
...

otherwise there would proper output on

cat /proc/device-tree/model

other than

Turing Machines Turing Pi 2 BMC

e.g.

Turing Pi 2 (v2.4)