Comment by pavehawk2007

AIA is still a work in progress. The last draft release was 18 days ago, and it is at version 0.3.0-31. Verify here: https://github.com/riscv/riscv-aia/releases

As the article mentions, there was a major change between 30 and 31 where the SETEIENUM/SETEIPNUM as well as the CLREIENUM/CLREIPNUM CSRs were removed. The issue on GitHub reads that they were removed since the architecture review board asked for them to be removed.

A manufacturer can use a draft spec, but it may be rendered outdated sooner rather than later.