Re: [RFC PATCH 2/4] dt-bindings: firmware: thead,th1520-aon: add a mailbox name for SBI

[Icenowy Zheng <uwu@icenowy.me>]

在 2025-08-14星期四的 09:49 +0200，Krzysztof Kozlowski写道：
> On 14/08/2025 09:30, Icenowy Zheng wrote:
> > 在 2025-08-14星期四的 09:18 +0200，Krzysztof Kozlowski写道：
> > > On 14/08/2025 09:07, Icenowy Zheng wrote:
> > > > The SBI firmware might want to communicate to the AON firmware
> > > > too.
> > > > 
> > > > Add a mbox-name item to allow to allocate a mailbox for SBI.
> > > > 
> > > > Signed-off-by: Icenowy Zheng <uwu@icenowy.me>
> > > > ---
> > > >  .../devicetree/bindings/firmware/thead,th1520-aon.yaml     | 7
> > > > ++++---
> > > >  1 file changed, 4 insertions(+), 3 deletions(-)
> > > > 
> > > > diff --git
> > > > a/Documentation/devicetree/bindings/firmware/thead,th1520-
> > > > aon.yaml
> > > > b/Documentation/devicetree/bindings/firmware/thead,th1520-
> > > > aon.yaml
> > > > index 3365124c7fd47..555465f4aab4e 100644
> > > > --- a/Documentation/devicetree/bindings/firmware/thead,th1520-
> > > > aon.yaml
> > > > +++ b/Documentation/devicetree/bindings/firmware/thead,th1520-
> > > > aon.yaml
> > > > @@ -26,11 +26,12 @@ properties:
> > > >      const: thead,th1520-aon
> > > >  
> > > >    mboxes:
> > > > -    maxItems: 1
> > > > +    maxItems: 2
> > > 
> > > 
> > > ABI break without explanation why ("allow" is not a reason to
> > > affect
> > > ABI) and its impact.
> > 
> > Is adding items an ABI break?
> 
> Adding required items is ABI break. You can easily test it. Apply
> patch
> #1 and test your DTS. Apply patch #2 and test your DTS. New warnings
> appear, so that's a proof of ABI impact.

Ah sorry I don't mean that item is required.

> 
> 
> > 
> > Or should I explicitly say "minItems: 1" here?
> 
> Yes, but you should clearly explain the impact. Is it working? Not
> working? Are you fixing something?

The jsonschema draft says "Omitting this keyword has the same behavior
as a value of 0." for minItems. [1]

[1]
https://json-schema.org/draft/2020-12/json-schema-validation#section-6.4.2-3

> 
> Best regards,
> Krzysztof