The specs themselves come with a lot of rationale for decisions taken.
But, as a starting point (from zero), I recommend the "RISC-V Reader" book, by the main authors of the ISA, as it makes a great introduction to the design of RISC-V.
The specs themselves come with a lot of rationale for decisions taken.
But, as a starting point (from zero), I recommend the "RISC-V Reader" book, by the main authors of the ISA, as it makes a great introduction to the design of RISC-V.