Re: [PATCH] irqchip/versatile-fpga: Apply clear-mask earlier

From: Linus Walleij
Date: Sun Mar 22 2020 - 07:46:24 EST


On Sat, Mar 21, 2020 at 2:40 PM Sungbo Eo <mans0n@xxxxxxxxxx> wrote:

> Clear its own IRQs before the parent IRQ get enabled, so that the
> remaining IRQs do not accidentally interrupt the parent IRQ controller.
>
> This patch also fixes a reboot bug on OX820 SoC, where the remaining
> rps-timer IRQ raises a GIC interrupt that is left pending. After that,
> the rps-timer IRQ is cleared during driver initialization, and there's
> no IRQ left in rps-irq when local_irq_enable() is called, which evokes
> an error message "unexpected IRQ trap".
>
> Fixes: bdd272cbb97a ("irqchip: versatile FPGA: support cascaded interrupts from DT")
> Signed-off-by: Sungbo Eo <mans0n@xxxxxxxxxx>
> Cc: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
> Cc: Daniel Golle <daniel@xxxxxxxxxxxxxx>

Good catch!
Reviewed-by: Linus Walleij <linus.walleij@xxxxxxxxxx>

Marc: Cc stable?

Yours,
Linus Walleij