[U-Boot-Users] Arithmetic expansion from shell

Hello all, I wanted to write a script which could parse file image header before booting. Initially we thought Hush script could do the job but it seems the arithmetic expansion is not supported with either the default command parser or the hush shell (no 'let' command either). Could you please confirm if this is correct?

Also, if the above is correct, I am planning to write a bootstrap function/command (board specific code) with something like

bootcmd=<bootsrap init cmd>; bootm

Is this write approach?

Thanks, Hemant.