They have what Intel call non-inclusive cache. Data is not duplicated in L2 and L3 like on consumer models. So in effect you get to use both L2 and L3. I've not tested it in depth, but my assumption is that the cache amount for comparison should be the total L2+L3 amount.
This may also apply to AMD Ryzen CPUs, since they use exclusive cache, but the L2 is far smaller and IMO not significant enough to bother with, even before we get to CCX complications. No, I don't know what the difference between exclusive and non-inclusive caches are.