Getting Started with Ibex
This page discusses initial steps and requirements to start using Ibex in your design.
Identification CSRs
The RISC-V Privileged Architecture specifies several read-only CSRs that identify the vendor and micro-architecture of a CPU.
These are mvendorid
, marchid
and mimpid
.
The fixed, read-only values for these CSRs are defined in rtl/cve2_pkg.sv
.
Implementers should carefully consider appropriate values for these registers.
Ibex, as an open source implementation, has an assigned architecture ID (marchid
) of 22.
(Allocations are specified in marchid.md of the riscv-isa-manual repository.)
If significant changes are made to the micro-architecture a different architecture ID should be used.
The vendor ID and implementation ID (mvendorid
and mimpid
) both read as 0 by default, meaning non-implemented.
Implementers may wish to use other values here.
Please see the RISC-V Privileged Architecture specification for more details on what these IDs represent and how they should be chosen.