To this day, my own KCP53000 core is *still* the only 64-bit FPGA-optimized core I'm aware of.
Both have their limitations, however; neither design can run Linux, for example.
I hope that my successor design (KCP53010 -- still vaporware!) will remedy some of them (it should be able to run Linux if it's ported), but it still won't be as complete or as fast as Rocket.
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