Re: [RFC PATCH v1 4/4] rust: add PL031 RTC driver

["Danilo Krummrich" <dakr@kernel.org>]

On Sun Jan 4, 2026 at 10:02 AM CET, Dirk Behme wrote:

> Do we want a common register access style in Rust drivers and want to
> encourge using the register macro for that? Or do we take what we have
> at the moment (like here) and eventually convert later to the register
> macro? Or not? Opinions?

Yes, the idea is that drivers use the register!() macro for definitions (this
has been what I am looking for since proposing it in [1]).

Please also see [2] for some more rationale and design considerations.

Ideally, we land the patch series moving the register!() macro from nova-core
(which we used as a playground for development and to proof the concept) to
common infrastructure this cycle.

This way drivers targeting next cycle or later can start using it right away.

Should we not make it in this cycle, we can also consider a feature branch to
share with upcoming drivers, but let's see how it goes first.

> I know that it is not ready yet and still in development, but what's
> about the register!() macro [1] [2]?

As mentioned above, it's not that it is not ready. We are actively using it in
nova-core for quite a while now, but we now have to move it to common
infrastructure.

It probably would have been better to do the move first and then extract generic
bitfield code afterwards, but we should be on track now. :)

- Danilo

[1] https://docs.kernel.org/gpu/nova/core/todo.html#generic-register-abstraction-rega
[2] https://lore.kernel.org/all/DD15H63RK1KJ.1J584C1QC4L28@kernel.org/