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References: <20240130095222.11177-1-wsa+renesas@sang-engineering.com>
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From: Geert Uytterhoeven <geert@linux-m68k.org>
Date: Thu, 1 Feb 2024 10:21:58 +0100
Message-ID: <CAMuHMdUB_9TNzo+GFbDZO-gjBUGfk7O7aEyJYG5pCw-Z1nK-pw@mail.gmail.com>
Subject: Re: [PATCH] arm64: dts: renesas: ulcb-kf: document a problemw with
 old firmware
To: Wolfram Sang <wsa+renesas@sang-engineering.com>
Cc: linux-renesas-soc@vger.kernel.org, Magnus Damm <magnus.damm@gmail.com>, 
	Rob Herring <robh+dt@kernel.org>, 
	Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>, Conor Dooley <conor+dt@kernel.org>, 
	devicetree@vger.kernel.org, linux-kernel@vger.kernel.org
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Hi Wolfram,

On Tue, Jan 30, 2024 at 10:52=E2=80=AFAM Wolfram Sang
<wsa+renesas@sang-engineering.com> wrote:
> Old firmware set the GPIO to output, so no interrupts could be read.
> Newer firmware does this correctly. The exact version could not be
> determined, sadly.
>
> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>

Thanks for your patch!

> --- a/arch/arm64/boot/dts/renesas/ulcb-kf.dtsi
> +++ b/arch/arm64/boot/dts/renesas/ulcb-kf.dtsi
> @@ -324,6 +324,7 @@ gpio_exp_77: gpio@77 {
>                 reg =3D <0x77>;
>                 gpio-controller;
>                 #gpio-cells =3D <2>;
> +               /* If these interrupts don't work, please update your fir=
mware */
>                 interrupt-controller;
>                 interrupt-parent =3D <&gpio5>;
>                 interrupts =3D <9 IRQ_TYPE_EDGE_FALLING>;

I'd rather not add such comments (especially +6y after the fact), as
this is the standard operating procedure in case something doesn't work.

Do you think we should sprinkle the following, too??

/* If secondary CPUs don't work, please update your firmware */
/* If cpuidle crashes, please update your firmware */
/* If watchdog restart doesn't work, please update your firmware */
/* If PSCI reboot doesn't work, please update your firmware */

Gr{oetje,eeting}s,

                        Geert

--=20
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k=
org

In personal conversations with technical people, I call myself a hacker. Bu=
t
when I'm talking to journalists I just say "programmer" or something like t=
hat.
                                -- Linus Torvalds