https://mp.weixin.qq.com/s/xP8JRhkmgUQf0QRm3S2mjA
根据RISC-V规范整理的几个文档。
1. 原文链接
2. Definitions, acronyms and abbreviations
3. User-Level ISA
4. Assembly Programmer's Handbook
5. CSRs
6. Privileged Instructions
7. Introduction
摘录自The RISC-V Instruction Set Manual Volume I: User-Level ISA, Chapter 1:
RISC-V (pronounced
isk- ve") is a new instruction set architecture (ISA) that was originally designed to support computer architecture research and education, but which we now hope will also become a standard free and open architecture for industry implementations. Our goals in de ning RISC-V include:
- A completely open ISA that is freely available to academia and industry.
- A real ISA suitable for direct native hardware implementation, not just simulation or binary translation.
- An ISA that avoids over-architecting" for a particular microarchitecture style (e.g., microcoded, in-order, decoupled, out-of-order) or implementation technology (e.g., full-custom, ASIC, FPGA), but which allows ecient implementation in any of these.
- An ISA separated into a small base integer ISA, usable by itself as a base for customized accelerators or for educational purposes, and optional standard extensions, to support general-purpose software development.
- Support for the revised 2008 IEEE-754 foating-point standard [14].
- An ISA supporting extensive user-level ISA extensions and specialized variants.
- Both 32-bit and 64-bit address space variants for applications, operating system kernels, and hardware implementations.
- An ISA with support for highly-parallel multicore or manycore implementations, including heterogeneous multiprocessors.
- Optional variable-length instructions to both expand available instruction encoding space and to support an optional dense instruction encoding for improved performance, static code size, and energy efficiency.
- A fully virtualizable ISA to ease hypervisor development.
- An ISA that simpli es experiments with new supervisor-level and hypervisor-level ISA designs.