Re: [net-next v3 2/5] dt-bindings: net: starfive,jh7110-dwmac: Add jhb100 support

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 2 potential issue(s) to consider:
- [Medium] The compatible string 'starfive,jhb100-dwmac' incorrectly uses 'starfive,jh7110-dwmac' as a fallback, violating Device Tree ABI backwards compatibility rules.
- [Medium] The schema logic for 'starfive,jhb100-dwmac' relies on the invalid fallback string, resulting in incorrect nesting and missing 'select' validation.
--

commit 99d98f58cde78e6cc89acf897a5b4bac3713e9c4
Author: Minda Chen <minda.chen@starfivetech.com>

dt-bindings: net: starfive,jh7110-dwmac: Add jhb100 support

This commit adds support for the jhb100 GMAC, which is based on the Synopsys
designware GMAC core. It introduces a new compatible string and updates the
interrupt and reset constraints, as the jhb100 hardware has only one reset
signal and one interrupt line.

> diff --git a/Documentation/devicetree/bindings/net/starfive,jh7110-dwmac.yaml b/Documentation/devicetree/bindings/net/starfive,jh7110-dwmac.yaml
> --- a/Documentation/devicetree/bindings/net/starfive,jh7110-dwmac.yaml
> +++ b/Documentation/devicetree/bindings/net/starfive,jh7110-dwmac.yaml
> @@ -30,6 +30,10 @@ properties:
>        - items:
>            - const: starfive,jh7110-dwmac
>            - const: snps,dwmac-5.20
> +      - items:
> +          - const: starfive,jhb100-dwmac
> +          - const: starfive,jh7110-dwmac
> +          - const: snps,dwmac-5.20

The starfive,jhb100-dwmac hardware physically provides only 1 interrupt and
1 reset, but the fallback starfive,jh7110-dwmac strictly requires 3
interrupts and 2 resets. Does this break Device Tree ABI backwards
compatibility? 

An unmodified legacy operating system matching the fallback would expect the
missing resources and might fail to initialize. Should the
starfive,jh7110-dwmac fallback be removed from this list?

[ ... ]

> @@ -107,20 +111,39 @@ allOf:
>            contains:
>              const: starfive,jh7110-dwmac
>      then:
> -      properties:
> -        interrupts:
> -          minItems: 3
> -          maxItems: 3
> -
> -        interrupt-names:
> -          minItems: 3
> -          maxItems: 3
> -
> -        resets:
> -          minItems: 2
> -
> -        reset-names:
> -          minItems: 2
> +      if:
> +        properties:
> +          compatible:
> +            contains:
> +              const: starfive,jhb100-dwmac

These interrupt and reset constraints for jhb100 are nested inside an outer
condition checking for starfive,jh7110-dwmac. If the invalid fallback is
removed from the compatible array above, will jhb100 nodes fail this outer
condition and silently bypass their specific constraints?

Furthermore, if a device tree correctly drops the jh7110 fallback, will
dt_binding_check silently ignore the jhb100 node entirely because it is
missing from the custom select block at the top of the schema? 

Could these constraints be evaluated in an independent if block, and the
new compatible string be added to the select block?

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260507094115.8355-1-minda.chen@starfivetech.com?part=2