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References: <20220421221159.31729-1-prabhakar.mahadev-lad.rj@bp.renesas.com> <20220421221159.31729-2-prabhakar.mahadev-lad.rj@bp.renesas.com>
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From:   Geert Uytterhoeven <geert@linux-m68k.org>
Date:   Thu, 28 Apr 2022 11:32:06 +0200
Message-ID: <CAMuHMdVrcT5iHUZUiCYmD12sS4F66BETBih36G7BzLTLuoQ9eQ@mail.gmail.com>
Subject: Re: [PATCH 1/2] dt-bindings: interrupt-controller: Add Renesas RZ/G2L
 Interrupt Controller
To:     Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Cc:     Marc Zyngier <maz@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Philipp Zabel <p.zabel@pengutronix.de>,
        "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" 
        <devicetree@vger.kernel.org>,
        Geert Uytterhoeven <geert+renesas@glider.be>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Linux-Renesas <linux-renesas-soc@vger.kernel.org>,
        Prabhakar <prabhakar.csengg@gmail.com>,
        Biju Das <biju.das.jz@bp.renesas.com>
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Hi Prabhakar,

On Fri, Apr 22, 2022 at 12:12 AM Lad Prabhakar
<prabhakar.mahadev-lad.rj@bp.renesas.com> wrote:
> Add DT bindings for the Renesas RZ/G2L Interrupt Controller.
>
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

Thanks for your patch!

> --- /dev/null
> +++ b/Documentation/devicetree/bindings/interrupt-controller/renesas,rzg2l-irqc.yaml
> @@ -0,0 +1,131 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/interrupt-controller/renesas,rzg2l-irqc.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Renesas RZ/G2L (and alike SoC's) Interrupt Controller (IA55)
> +
> +maintainers:
> +  - Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> +  - Geert Uytterhoeven <geert+renesas@glider.be>
> +
> +description: |
> +  IA55 performs various interrupt controls including synchronization for the external
> +  interrupts of NMI, IRQ, and GPIOINT and the interrupts of the built-in peripheral
> +  interrupts output by each IP. And it notifies the interrupt to the GIC
> +    - IRQ sense select for 8 external interrupts, mapped to 8 GIC SPI interrupts
> +    - GPIO pins used as external interrupt input pins, mapped to 32 GIC SPI interrupts
> +    - NMI edge select (NMI is not treated as NMI exception and supports fall edge and
> +      stand-up edge detection interrupts)
> +
> +allOf:
> +  - $ref: /schemas/interrupt-controller.yaml#
> +
> +properties:
> +  compatible:
> +    items:
> +      - enum:
> +          - renesas,r9a07g044-irqc    # RZ/G2L
> +      - const: renesas,rzg2l-irqc
> +
> +  '#interrupt-cells':
> +    const: 2

What is the meaning of the cells? IRQ number + flags, I assume?
How are the numbers mapped, do you need a DT bindings header?
Perhaps it would make sense to increase to 3 cells, so you can use
one cell for the type (cfr. e.g. GIC_SPI), and the second for the
plain index within the type?

The rest LGTM, but I'm not an interrupt expert, so I'm curious in
hearing Marc's opinion.

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

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