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Date:   Sun, 26 Jun 2022 13:35:54 +0100
Message-ID: <87tu87eh5h.wl-maz@kernel.org>
From:   Marc Zyngier <maz@kernel.org>
To:     Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Sagar Kadam <sagar.kadam@sifive.com>,
        Palmer Dabbelt <palmer@dabbelt.com>,
        Paul Walmsley <paul.walmsley@sifive.com>,
        linux-riscv@lists.infradead.org, devicetree@vger.kernel.org,
        Geert Uytterhoeven <geert+renesas@glider.be>,
        linux-renesas-soc@vger.kernel.org, linux-kernel@vger.kernel.org,
        Prabhakar <prabhakar.csengg@gmail.com>,
        Biju Das <biju.das.jz@bp.renesas.com>
Subject: Re: [PATCH v2 1/2] dt-bindings: interrupt-controller: sifive,plic: Document Renesas RZ/Five SoC
In-Reply-To: <20220626004326.8548-2-prabhakar.mahadev-lad.rj@bp.renesas.com>
References: <20220626004326.8548-1-prabhakar.mahadev-lad.rj@bp.renesas.com>
        <20220626004326.8548-2-prabhakar.mahadev-lad.rj@bp.renesas.com>
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On Sun, 26 Jun 2022 01:43:25 +0100,
Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> wrote:
> 
> Document Renesas RZ/Five (R9A07G043) SoC.
> 
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> ---
> v1->v2:
> * Fixed binding doc
> * Fixed review comments pointed by Krzysztof.
> 
> RFC->v1:
> * Fixed Review comments pointed by Geert and Rob
> ---
>  .../sifive,plic-1.0.0.yaml                    | 44 +++++++++++++++++--
>  1 file changed, 41 insertions(+), 3 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/interrupt-controller/sifive,plic-1.0.0.yaml b/Documentation/devicetree/bindings/interrupt-controller/sifive,plic-1.0.0.yaml
> index 27092c6a86c4..59df367d1e44 100644
> --- a/Documentation/devicetree/bindings/interrupt-controller/sifive,plic-1.0.0.yaml
> +++ b/Documentation/devicetree/bindings/interrupt-controller/sifive,plic-1.0.0.yaml
> @@ -28,7 +28,10 @@ description:
>  
>    While the PLIC supports both edge-triggered and level-triggered interrupts,
>    interrupt handlers are oblivious to this distinction and therefore it is not
> -  specified in the PLIC device-tree binding.
> +  specified in the PLIC device-tree binding for SiFive PLIC (and similar PLIC's),
> +  but for the Renesas RZ/Five Soc (AX45MP AndesCore) which has NCEPLIC100 we need
> +  to specify the interrupt type as the flow for EDGE interrupts is different
> +  compared to LEVEL interrupts.
>  
>    While the RISC-V ISA doesn't specify a memory layout for the PLIC, the
>    "sifive,plic-1.0.0" device is a concrete implementation of the PLIC that
> @@ -57,6 +60,7 @@ properties:
>            - enum:
>                - allwinner,sun20i-d1-plic
>            - const: thead,c900-plic
> +      - const: renesas,r9a07g043-plic

Since it is the NCEPLIC100 that is broken, shouldn't the compatible
string actually reflect that? I'd rather see 'andes,nceplic100' once
and for all instead of starting with Renesas, quickly followed by all
the other licensees that will inevitably integrate the same IP (which
isn't even specific to the AX45MP).

This IP also comes with all sort of added (mis-)features, which may or
may not be used in the future, and it would make sense to identify it
specifically.

	M.

-- 
Without deviation from the norm, progress is not possible.