Re: [PATCH v4 01/16] dt-bindings: serial: renesas,rsci: Document RZ/G3E support

From: Geert Uytterhoeven

Date: Fri Nov 28 2025 - 07:53:45 EST


Hi Biju,

On Tue, 25 Nov 2025 at 16:06, Biju <biju.das.au@xxxxxxxxx> wrote:
> From: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>
>
> Add documentation for the serial communication interface (RSCI) found on
> the Renesas RZ/G3E (R9A09G047) SoC. The RSCI IP on this SoC is identical
> to that on the RZ/T2H (R9A09G077) SoC, but it has a 32-stage FIFO compared
> to 16 on RZ/T2H. It supports both FIFO and non-FIFO mode operation. RZ/G3E
> has 6 clocks(5 module clocks + 1 external clock) compared to 3 clocks
> (2 module clocks + 1 external clock) on RZ/T2H, and it has multiple resets.
>
> Acked-by: Conor Dooley <conor.dooley@xxxxxxxxxxxxx>
> Signed-off-by: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>
> ---
> v3->v4:
> * Dropped separate compatible for non-FIFO mode and instead using single
> compatible "renesas,r9a09g047-rsci" as non-FIFO mode can be achieved
> by software configuration.
> * Renamed clock-names bus->pclk
> * Rearranged clock-names tclk{4, 16, 64}
> * Retained the tag as the changes are trivial.

Thanks for the update!

> --- a/Documentation/devicetree/bindings/serial/renesas,rsci.yaml
> +++ b/Documentation/devicetree/bindings/serial/renesas,rsci.yaml

> @@ -62,6 +82,46 @@ required:
> - clock-names
> - power-domains
>
> +allOf:
> + - $ref: serial.yaml#
> +
> + - if:
> + properties:
> + compatible:
> + contains:
> + const: renesas,r9a09g077-rsci
> + then:
> + properties:
> + clocks:
> + minItems: 2
> + maxItems: 3
> +
> + clock-names:
> + minItems: 2
> + maxItems: 3
> +
> + - if:
> + properties:
> + compatible:
> + contains:
> + const: renesas,r9a09g047-rsci
> + then:
> + properties:
> + clocks:
> + minItems: 5
> + maxItems: 6
> +
> + clock-names:
> + minItems: 5
> + maxItems: 6
> +
> + required:
> + - resets
> + - reset-names
> + else:
> + properties:
> + resets: false

While technically correct, please move the contents of the "else" branch
to the "if ... renesas,r9a09g077-rsci" above, to increase uniformity.

Also, RZ/G3E RSCI has two more interrupts: AED (active edge detection)
and BFD (bus collision detection). Sorry for missing that before.

Gr{oetje,eeting}s,

Geert

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

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds