Re: [PATCH v5 0/9] Introduce bitfield and move register macro to rust/kernel/

[Alexandre Courbot]

On Tue Sep 30, 2025 at 11:45 PM JST, Joel Fernandes wrote:
> Hello!
>
> These patches extract and enhance the bitfield support in the register macro in
> nova to define Rust structures with bitfields. It then moves out the bitfield
> support into the kenrel crate and further enhances it. This is extremely useful
> as it allows clean Rust structure definitions without requiring explicit masks
> and shifts.

The extraction and move in themselves (patches 1-4 and maybe the KUNIT
one) look good to me. For the remainder, it will depend on whether the
BoundedInt idea sticks or not as it changes the design in a way that
makes most of these patches unneeded. In any case I think this can be
worked on after the split and extraction.

Patch 5 should probably be dropped as it has the potential to clear
register fields that are useful to the hardware but have no entry in the
`register!` definition, making read-update-write updates of registers
unpredictable.