Re: [PATCH v3 1/6] dt-bindings: watchdog: renesas,wdt: Add support for RZ/T2H and RZ/N2H

[Geert Uytterhoeven]

Hi Prabhakar,

On Mon, 4 Aug 2025 at 21:57, Prabhakar <prabhakar.csengg@xxxxxxxxx> wrote:
> From: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
>
> Extend the Renesas WDT device tree bindings to support the watchdog timer
> found on the RZ/T2H (R9A09G077) and RZ/N2H (R9A09G087) SoCs.
>
> The RZ/T2H WDT is mostly compatible with the one found on the RZ/V2H(P),
> but includes an additional register and differs in the clock division
> ratio settings for the WDTCR[CKS] field. To reflect these differences,
> introduce a new compatible string, "renesas,r9a09g077-wdt".
>
> The binding schema is updated accordingly. On RZ/T2H, the WDT does not
> require the "resets" property. It also requires two register regions and
> the presence of a "power-domains" property. The "clock-names" property is
> limited to a single entry, "pclk", for this SoC.
>
> The RZ/N2H SoC uses the same WDT IP as the RZ/T2H. It is supported by
> using "renesas,r9a09g087-wdt" as the primary compatible string, with
> "renesas,r9a09g077-wdt" listed as a fallback to describe the shared
> hardware features.
>
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
> Reviewed-by: Rob Herring (Arm) <robh@xxxxxxxxxx>

Thanks for your patch!

> --- a/Documentation/devicetree/bindings/watchdog/renesas,wdt.yaml
> +++ b/Documentation/devicetree/bindings/watchdog/renesas,wdt.yaml
> @@ -81,10 +81,17 @@ properties:
>                - renesas,r9a09g056-wdt # RZ/V2N
>            - const: renesas,r9a09g057-wdt # RZ/V2H(P)
>
> -      - const: renesas,r9a09g057-wdt       # RZ/V2H(P)
> +      - enum:
> +          - renesas,r9a09g057-wdt    # RZ/V2H(P)
> +          - renesas,r9a09g077-wdt    # RZ/T2H
> +
> +      - items:
> +          - const: renesas,r9a09g087-wdt # RZ/N2H
> +          - const: renesas,r9a09g077-wdt # RZ/T2H
>
>    reg:
> -    maxItems: 1
> +    minItems: 1
> +    maxItems: 2

The second register block is just a single register, right?
Showing an (early) example of the device node would make such
details easier to notice...

Reviewed-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

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when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds