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

[Marc Zyngier]

On 2020-03-21 13:38, Sungbo Eo 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>
> ---
>  drivers/irqchip/irq-versatile-fpga.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/irqchip/irq-versatile-fpga.c
> b/drivers/irqchip/irq-versatile-fpga.c
> index 70e2cfff8175..f1386733d3bc 100644
> --- a/drivers/irqchip/irq-versatile-fpga.c
> +++ b/drivers/irqchip/irq-versatile-fpga.c
> @@ -212,6 +212,9 @@ int __init fpga_irq_of_init(struct device_node 
> *node,
>  	if (of_property_read_u32(node, "valid-mask", &valid_mask))
>  		valid_mask = 0;
>
> +	writel(clear_mask, base + IRQ_ENABLE_CLEAR);
> +	writel(clear_mask, base + FIQ_ENABLE_CLEAR);
> +
>  	/* Some chips are cascaded from a parent IRQ */
>  	parent_irq = irq_of_parse_and_map(node, 0);
>  	if (!parent_irq) {
> @@ -221,9 +224,6 @@ int __init fpga_irq_of_init(struct device_node 
> *node,
>
>  	fpga_irq_init(base, node->name, 0, parent_irq, valid_mask, node);
>
> -	writel(clear_mask, base + IRQ_ENABLE_CLEAR);
> -	writel(clear_mask, base + FIQ_ENABLE_CLEAR);
> -
>  	/*
>  	 * On Versatile AB/PB, some secondary interrupts have a direct
>  	 * pass-thru to the primary controller for IRQs 20 and 22-31 which 
> need

You're on a roll! ;-) Queued for 5.7.

Thanks,

        M.
--
Jazz is not dead. It just smells funny...