Re: [PATCH 1/2] dt-bindings: mfd: syscon: introduce no-auto-mmio property for syscons

From: Conor Dooley

Date: Wed Oct 29 2025 - 14:37:30 EST


On Wed, Oct 29, 2025 at 08:41:51PM +0300, Dan Carpenter wrote:
> On Wed, Oct 29, 2025 at 05:33:48PM +0000, Conor Dooley wrote:
> > On Wed, Oct 29, 2025 at 08:27:05PM +0300, Dan Carpenter wrote:
> > > Generally, syscons are created automatically and accessed direclty via
> > > MMIO however sometimes syscons might only be accessible from the secure
> > > partition or through SCMI etc. Introduce the no-auto-mmio property to
> > > tell the operating system that the syscon needs to be handled manually.
> >
> > "System controller node represents a register region containing a set
> > of miscellaneous registers."
> >
> > If this isn't actually a register region, but is instead an interface
> > provided by SCMI or whatever "secure partition" is (optee?), why is the
> > syscon compatible being used for the device in the first place?
>
> In the case that I'm looking at, it really is a syscon. So right now
> we're upstreaming it and it's an MMIO syscon. Very straight forward.
> But later, I guess, they want to have a new firmware which will only let
> you access the same registers through SCMI.

When the programming model changes, the compatible should too, no?

Attachment: signature.asc
Description: PGP signature