Don't know about the exact CPU req. but a highly optimized version runs on RP2040 as part of doom port. rp2040 OPL2 emulator (for DOOM) and used by picogus found here on VOGONS

I've just managed to build this thingy, without any serious skill. Only addition, that I had to set the H1L-H4L solder bridges on the pcm5102, otherwise sound was totally distorted. Now it works like charm and it adds some live to my soundless Contura Aero. Thanks for publishing your project! …