reference - riscv2os/riscv2os GitHub Wiki ๅ่ๆ็ป ianchen0119/AwesomeCS/่จ็ฎๆฉ็งๅญธไน็พ RISC-V ISA Specification -- Volume 1, Unprivileged Spec v. 20191213 RISC-V ISA Specification -- Volume 2, Privileged Spec v. 20211203 RISC-V ๆๅไธๆฌๅผๆบๆไปค้็ๆๅ xv6: a simple, Unix-like teaching operating system (2020/PDF)