I would like to get FDT2 tool likke functonality in Lunix
I want to connect RPI to the WP76xx and perform update.
is there an open source that I can cross compile?
you should use MBPL.
It also has the FW download tool:
https://source.sierrawireless.com/resources/airprime/software/mbpl/mbpl-software-latest/#sthash.ZQMqOllZ.dpbs