Re: [RFC] dt-bindings: riscv: enum for riscv,isa

From: Palmer Dabbelt
Date: Thu Apr 22 2021 - 23:32:47 EST


On Tue, 06 Apr 2021 12:05:34 PDT (-0700), xypron.glpk@xxxxxx wrote:
In Documentation/devicetree/bindings/riscv/cpus.yaml I find for riscv,isa:

enum:
- rv64imac
- rv64imafdc

This implies that 'rv64imafc' or 'rv64imafdqc' would be illegal values
while these combinations of extensions would be compliant with "The
RISC-V Instruction Set Manual".

To me it does not make much sense to try to enumerate all permissible
permutations of RISC-V extensions.

Shouldn't this enum be removed and replaced by examples?

I'm generally OK with that, but I'm not sure how to do it: won't we fail the scheme checks if we don't have something defined for "riscv,isa"?