Let me confirm about power mode.
I'm checking a section 18.104.22.168 of following document.
Fisrt, I start both of A7 and M4 core. ⇒ Both core are in "RUN" state.
Then, I chage a mode of A7 to "SUSPEND". ⇒ A7 is in "SUSPEND" and M4 is in "RUN" state.
Finaly, M4 turn out A7 by interrupt signal. ⇒ Both core are in "RUN" state.
Can i.MX7D do that?