I have the same question - but unlike the OP, I do call
before I call hibernate.
So I'm assuming an interrupt is occurring, bringing the uC out of hibernate - can I read a reg to know which interrupt caused the resume out of hibernate?
I'm no expert in this matter (iI struggle with similar issues using CyPmSleep()) but what I suppose is that when using PmCyHibernate() the IO pins of the processor become high impedant (at least they don't have the same behaviour as when using CyPmSleep()).. This could cause a involuntary interrupt when a IO pin driffts from high to low or vice versa.