On Arm GICv5 systems, the IWB (Interrupt Wire Bridge) handles wired interrupts
and it is in charge of translating interrupt wires to GICv5 ITS messages.
In ACPI systems, an IWB is backed by a platform device. Device drivers for
devices whose IRQs are routed to an IWB might probe earlier than the IWB device
driver, which can result in failures in that until the IWB driver is probed and
its IRQ domain is duly registered, IRQs routed to it cannot be resolved.
Some interrupt controllers for the RISC-V architecture suffer from the same
issue; RISC-V, in its ACPI IRQ layer solved the problem by automatically
creating device dependencies that result in the interrupt controllers drivers
being probed before any device driver whose devices IRQs are routed to them is
probed.
Instead of reinventing the wheel, this series move the aforementioned RISC-V
code to generic ACPI IRQ handling code (while fixing some bits and pieces) and
implement GICv5 IWB ACPI probe deferral on top of it.
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
---
Changes in v2:
- Split the patchset in several logic units according to review
- Link to v1: https://patch.msgid.link/20260505-gic-v5-acpi-iwb-probe-deferral-v1-0-b37b85998362@kernel.org
---
Lorenzo Pieralisi (6):
ACPI: RISC-V: Fix riscv_acpi_irq_get_dep() loop termination
ACPI: RISC-V: Check acpi_get_handle() status in riscv_acpi_add_prt_dep()
ACPI: RISC-V: Fix riscv_acpi_add_prt_dep() loop handling
ACPI: irq: Move RISC-V interrupt controllers autodep to ACPI IRQ code
ACPI/IORT: Implement ACPI infrastructure to enable GICv5 IWB probe deferral
irqchip/gic-v5: Enable GICv5 IWB ACPI probe ordering detection
arch/riscv/include/asm/acpi.h | 1 +
drivers/acpi/arm64/iort.c | 22 ++++-
drivers/acpi/irq.c | 172 +++++++++++++++++++++++++++++++++++-
drivers/acpi/riscv/irq.c | 141 +----------------------------
drivers/acpi/scan.c | 1 +
drivers/irqchip/irq-gic-v3.c | 2 +-
drivers/irqchip/irq-gic-v5-iwb.c | 5 ++
drivers/irqchip/irq-gic-v5.c | 13 ++-
drivers/irqchip/irq-gic.c | 2 +-
drivers/irqchip/irq-loongarch-cpu.c | 2 +-
drivers/irqchip/irq-riscv-intc.c | 3 +-
include/linux/acpi.h | 5 +-
include/linux/acpi_iort.h | 3 +-
13 files changed, 218 insertions(+), 154 deletions(-)
---
base-commit: 5d6919055dec134de3c40167a490f33c74c12581
change-id: 20260427-gic-v5-acpi-iwb-probe-deferral-cdc849b1a854
Best regards,
--
Lorenzo Pieralisi <lpieralisi@kernel.org>