TimeQuest – Problem with Crossing Clock Domains

How do you go from a 40MHz clock to a 50MHz clock? Do you have logic that determines which latch clock is a repeat and ignores it?

Are both PLLs driven by the same source clock? (Otherwise it won't work at all)

Go to Assignments -> Settings -> Fitter Settings and turn on Optimize hold Timing and check multicorner analysis.

That being said, you're asking it to add 15ns of delay. If the router adds 15ns of delay at the slow corner, assume that's at least 30ns of delay at the fast corner, and it will fail setup. Because of the relationships, what you're asking is impossible.

I would just phase-shift your 50MHz clock forward a bit, say 3ns or something like that(it gets confusing due to the different clock periods, so you may need to draw it out and find the best one.)