Re: [PATCH net-next v6 1/3] dt-bindings: ptp: renesas,rcar-gen4-gptp: Add R-Car Gen4

[email protected] Tue, 04 Aug 2026 09:53:05 +0000
Newsgroups org.kernel.vger.linux-devicetree
Message-ID <[email protected]>
Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [High] The standalone gPTP node will cause overlapping memory regions or schema validation failures due to conflicts with existing ethernet bindings.
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--- Patch [1]: [PATCH net-next v6 1/3] dt-bindings: ptp: renesas,rcar-gen4-gptp: Add R-Car Gen4 ---
commit 1e91aef0621f1bc3f4049383c20bf5b76369d35b
Author: Niklas Söderlund <[email protected]>

dt-bindings: ptp: renesas,rcar-gen4-gptp: Add R-Car Gen4
    
This commit adds device tree bindings for the R-Car Gen4 gPTP timer. The
timer enables accurate clock synchronization and is shared among Ethernet
devices like RSWITCH, RAVB, and RTSN depending on the specific Gen4 platform.

> diff --git a/Documentation/devicetree/bindings/ptp/renesas,rcar-gen4-gptp.yaml b/Documentation/devicetree/bindings/ptp/renesas,rcar-gen4-gptp.yaml
> new file mode 100644
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/ptp/renesas,rcar-gen4-gptp.yaml
[ ... ]
> +properties:
> +  compatible:
> +    items:
> +      - enum:
> +          - renesas,r8a779f0-gptp # S4-8
> +          - renesas,r8a779g0-gptp # V4H
> +          - renesas,r8a779h0-gptp # V4M
> +      - const: renesas,rcar-gen4-gptp
> +
> +  reg:
> +    maxItems: 1

[Severity: High]
Does defining this standalone MMIO region for the gPTP timer conflict with the
already-claimed gptp region required by the established Gen4 ethernet bindings?

If a new standalone gPTP node maps the 0xe6449000 MMIO region on R-Car V4H as
intended, it will overlap with the existing renesas,ethertsn.yaml binding
which explicitly requires the gptp region (mapping the exact same address) in
its reg-names.

Defining both nodes in the device tree could result in overlapping memory
regions and cause runtime probe failures (-EBUSY).

If the overlap is resolved by removing the region from the ethernet node,
wouldn't dt_binding_check fail because renesas,ethertsn.yaml was not updated
in this patch series to make the gptp region optional or deprecated?

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Sashiko AI review · https://sashiko.dev/#/patchset/[email protected]?part=1