Hi, I'm a Ph.D. student at UC Berkeley on the RISC-V team. Happy to answer any questions about the RISC-V ISA or Rocket, our open-source reference implementation.
Since there's always confusion about it, I'll start off by clarifying the difference between the two. RISC-V is an open-source ISA standard. Rocket is an implementation of this ISA which also happens to be open source. We do not intend for the ISA to be tied to a single reference implementation. The intention for RISC-V is to enable many different implementations (whether open-source or proprietary). These different implementations can all run an open-source software ecosystem, which currently consists of a GNU toolchain, LLVM, and Linux kernel port.
Since there's always confusion about it, I'll start off by clarifying the difference between the two. RISC-V is an open-source ISA standard. Rocket is an implementation of this ISA which also happens to be open source. We do not intend for the ISA to be tied to a single reference implementation. The intention for RISC-V is to enable many different implementations (whether open-source or proprietary). These different implementations can all run an open-source software ecosystem, which currently consists of a GNU toolchain, LLVM, and Linux kernel port.