Excellent find, an academic paper announcing the book is here

https://peer.asee.org/57147.pdf

Harris and Harris (no relation) have an excellent book on digital design using RISC-V as the domain problem, https://pages.hmc.edu/harris/ddca/ddcarv.html

https://pages.hmc.edu/harris/ddca/

Their books are perfect, and I hope this textbook gets adopted by thousands of colleges. Our RISC-V future is bright, now we need one on SoC bringup and getting your OS running on that SoC.