[tip: irq/core] ACPI: irq: Add interrupt affinity reporting interface

tip-bot2 for Marc Zyngier
2025-10-27T16:31:24Z

The following commit has been merged into the irq/core branch of tip:

Commit-ID: 5324fe21ba9b77b299c02191645a97777cdd73ac
Gitweb: https://git.kernel.org/tip/5324fe21ba9b77b299c02191645a97777cdd73ac
Author: Marc Zyngier <maz@kernel.org>
AuthorDate: Mon, 20 Oct 2025 13:29:19 +01:00
Committer: Thomas Gleixner <tglx@linutronix.de>
CommitterDate: Mon, 27 Oct 2025 17:16:32 +01:00

ACPI: irq: Add interrupt affinity reporting interface

Plug the irq_populate_fwspec_info() helper into the ACPI layer to offer an
interrupt 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@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Will Deacon <will@kernel.org>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Acked-by: Rafael J. Wysocki (Intel) <rafael@kernel.org>
Link: https://patch.msgid.link/20251020122944.3074811-3-maz@kernel.org
---
drivers/acpi/irq.c | 19 +++++++++++++++++++
include/linux/acpi.h | 7 +++++++
2 files changed, 26 insertions(+)

diff --git a/drivers/acpi/irq.c b/drivers/acpi/irq.c
index 76a856c..d159515 100644
--- a/drivers/acpi/irq.c
+++ b/drivers/acpi/irq.c
@@ -300,6 +300,25 @@ 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;
+ struct irq_fwspec fwspec;
+ unsigned long flags;
+
+ if (acpi_irq_parse_one(handle, index, &fwspec, &flags))
+ return NULL;
+
+ if (irq_populate_fwspec_info(&fwspec, &info))
+ return NULL;
+
+ if (!(info.flags & IRQ_FWSPEC_INFO_AFFINITY_VALID))
+ return NULL;
+
+ return info.affinity;
+}
+
/**
* 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 5ff5d99..607db77 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