[Synopsys dc_shell-xg-t] how to generate DFT scan chain for multiple files/modules?

[joder]

Dear all,

I've met a problems of inserting scan chain in a top module, A with instances of module B and C.
How do I do the scan chain to generate a final complete script?
Do I generate a sub script for each sub module of B and C, respectively and then generate a top script for top module A?
Or I can generate a top-down script to do the whole scan chain?

Thx in advance for the help.
Joder