Simple script (needs to run on a Linux host so awk can be used) to show all disks and versions of firmware. awk is used tostrip the disk name then to remove duplicate lines
linuxhost# ssh -l admin cluster01 disk show -fields model,firmware-revision | awk '{print $2,$3}' | awk '!/./ || !seen[$0]++' | grep -v "entries"
firmware-revision model
----------------- ----------------
NA00 X308_WKOJN03TSSM
NA00 X308_THARR03TSSM