Re: [PATCH] arm64: dts: renesas: ulcb-kf: document a problemw with old firmware

From: Geert Uytterhoeven
Date: Thu Feb 01 2024 - 04:23:20 EST


Hi Wolfram,

On Tue, Jan 30, 2024 at 10:52 AM Wolfram Sang
<wsa+renesas@xxxxxxxxxxxxxxxxxxxx> 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@xxxxxxxxxxxxxxxxxxxx>

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 = <0x77>;
> gpio-controller;
> #gpio-cells = <2>;
> + /* If these interrupts don't work, please update your firmware */
> interrupt-controller;
> interrupt-parent = <&gpio5>;
> interrupts = <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

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68korg

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