RISC-V is an ISA or Instruction Set Architecture. This defines the interface between hardware and software. If software and hardware both follow the specificat

RISC-V is an ISA or Instruction Set Architecture. This defines the interface between hardware and software. If software and hardware both follow the specification, then the software will run on the hardware, and the hardware will run the software. Both the hardware and the software could be entirely proprietary and extremely locked up, while compliant, as that'd fall well outside the ISA's scope.