On Mon, Sep 8, 2025 at 6:31 PM Marc Zyngier <maz@xxxxxxxxxx> wrote: > > Plug the irq_populate_fwspec_info() helper into the ACPI layer > to offer an IRQ affinity reporting function. This is currently > only supported for the CONFIG_ACPI_GENERIC_GSI configurations, > but could later be extended to legacy architectures if necessary. > > Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx> > --- > drivers/acpi/irq.c | 15 +++++++++++++++ > include/linux/acpi.h | 7 +++++++ > 2 files changed, 22 insertions(+) > > diff --git a/drivers/acpi/irq.c b/drivers/acpi/irq.c > index 76a856c32c4d0..22f93fe23ddce 100644 > --- a/drivers/acpi/irq.c > +++ b/drivers/acpi/irq.c > @@ -300,6 +300,21 @@ int acpi_irq_get(acpi_handle handle, unsigned int index, struct resource *res) > } > EXPORT_SYMBOL_GPL(acpi_irq_get); > > +const struct cpumask *acpi_irq_get_affinity(acpi_handle handle, > + unsigned int index) > +{ > + struct irq_fwspec_info info; > + unsigned long flags; > + > + if (!acpi_irq_parse_one(handle, index, &info.fwspec, &flags)) { > + if (!irq_populate_fwspec_info(&info) && > + info.flags & IRQ_FWSPEC_INFO_AFFINITY_VALID) > + return info.affinity; > + } I would prefer fewer logical negations to be used in this, for instance: if (acpi_irq_parse_one(handle, index, &info.fwspec, &flags)) return NULL; if (irq_populate_fwspec_info(&info)) return NULL; if (info.flags & IRQ_FWSPEC_INFO_AFFINITY_VALID) return info.affinity; return NULL; > + > + return NULL; > +} > + > /** > * acpi_set_irq_model - Setup the GSI irqdomain information > * @model: the value assigned to acpi_irq_model > diff --git a/include/linux/acpi.h b/include/linux/acpi.h > index 1c5bb1e887cd1..c506ae4bacc86 100644 > --- a/include/linux/acpi.h > +++ b/include/linux/acpi.h > @@ -1509,12 +1509,19 @@ static inline int acpi_parse_spcr(bool enable_earlycon, bool enable_console) > > #if IS_ENABLED(CONFIG_ACPI_GENERIC_GSI) > int acpi_irq_get(acpi_handle handle, unsigned int index, struct resource *res); > +const struct cpumask *acpi_irq_get_affinity(acpi_handle handle, > + unsigned int index); > #else > static inline > int acpi_irq_get(acpi_handle handle, unsigned int index, struct resource *res) > { > return -EINVAL; > } > +static inline const struct cpumask *acpi_irq_get_affinity(acpi_handle handle, > + unsigned int index) > +{ > + return NULL; > +} > #endif > > #ifdef CONFIG_ACPI_LPIT > --