Concluding remarks

Whereas the notion of open source seemed to be reserved for software aspects, with Linux distributions or office suites such as OpenOffice, the arrival of RISC-V showed that the concept could be applied to instruction sets, thereby facilitating architectural innovation: no need to buy a license for a proprietary instruction set, or to develop your own instruction set with all the associated software development costs.

The rise of RISC-V is the result of a number of judicious choices:

• definition of a clean minimal RISC kernel without the errors contained in the RISC instruction sets of the 1980s;

• modular structure with extensions to provide a general-purpose instruction set (G) with the same capabilities as proprietary instruction sets, or low-end variants (complexity and minimum code...