[PATCH v2 01/25] irqdomain: Add firmware info reporting interface

[Jonathan Cameron]

On Mon, 15 Sep 2025 09:56:38 +0100
Marc Zyngier <maz at kernel.org> wrote:

> Allow an irqdomain callback to report firmware-provided information
> that is otherwise not available in a generic way. This is reported
> using a new data structure (struct irq_fwspec_info).
> 
> This callback is optional and the only information that can be
> reported currently is the affinity of an interrupt. However, the
> containing structure is designed to be extensible, allowing other
> potentially relevant information to be reported in the future.
> 
> Signed-off-by: Marc Zyngier <maz at kernel.org>
Hi Marc,

> ---
>  include/linux/irqdomain.h | 28 ++++++++++++++++++++++++++++
>  kernel/irq/irqdomain.c    | 32 +++++++++++++++++++++++++++-----
>  2 files changed, 55 insertions(+), 5 deletions(-)
> 
> diff --git a/include/linux/irqdomain.h b/include/linux/irqdomain.h
> index 4a86e6b915dd6..34993bf8293c4 100644
> --- a/include/linux/irqdomain.h
> +++ b/include/linux/irqdomain.h
> @@ -44,6 +44,24 @@ struct irq_fwspec {
>  	u32			param[IRQ_DOMAIN_IRQ_SPEC_PARAMS];
>  };
>  
> +/**
> + * struct irq_fwspec_info - firmware provided IRQ information structure
> + *
> + * @fwspec:		Firmware-specific interrupt specifier

Not aligning with what is in the structure that I can see.

> + * @cpumask:		Affinity mask for this interrupt
> + * @flags:		Information validity flags
> + *
> + * This structure reports firmware-specific information about an
> + * interrupt. The only significant information is the affinity of a
> + * per-CPU interrupt, but this is designed to be extended as required.
> + */
> +struct irq_fwspec_info {
> +	unsigned long		flags;
> +	const struct cpumask	*affinity;
> +};