Well all philosophy boils down to physics, so I suppose this falls under my jurisdiction
I used to be of the belief that omniscience precluded genuine free will, but I've since changed my mind. Though I don't believe any omniscience exists, and I'm on the fence about free will, I don't see the two as mutually exclusive.
Omniscience means that your decisions are known. But they're still just that: your decisions. What you freely choose may be known by God (or whatever entity is omniscient), but he isn't
forcing you to choose the decision you will make, the choice is still yours. If we have some 'soul' or 'spirit' that solves the problem of how we can be truly creative or spontaneous in our decision making*, that still wouldn't necessarily preclude an omniscient being from foreknowing what it is we will freely decide. The 'free' part means its our decision, not that it's unknowable.
That's my take, at least
*From a scientific point of view, a highly complex quantum mechanical interaction in the brain's synapses may result in a very sophisticated sorting algorithm, much like the sophisticated computer programmes that arise ultimately from rather basic logic gates, could give rise to a 'genuine free will' algorithm. Maybe, in contrast to epiphenomenalism, that's the reason why the concious mind evolved - to act as a decision making tool of such sophistication that conciousness was the inevitable outcome of such a collation of sensory data. Maybe