Unlike OF framework, the irqchip probe using IRQCHIP_ACPI_DECLARE has no
order defined. Depending on the Makefile is not a good idea. So,
usually it is worked around by mandating only root interrupt controller
probed using IRQCHIP_ACPI_DECLARE and other interrupt controllers are
probed via cascade mechanism.
However, this is also not a clean solution because if there are multiple
root controllers (ex: RINTC in RISC-V which is per CPU) which need to be
probed first, then the cascade will happen for every root controller.
So, introduce an architecture specific weak function
arch_sort_irqchip_probe() to order the probing of the interrupt
controllers which can be implemented by different architectures as per
their interrupt controller hierarchy.
Signed-off-by: Sunil V L <sunilvl@xxxxxxxxxxxxxxxx>
Tested-by: Björn Töpel <bjorn@xxxxxxxxxxxx>
---
drivers/acpi/scan.c | 3 +++
include/linux/acpi.h | 2 ++
2 files changed, 5 insertions(+)
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 59771412686b..52a9dfc8e18c 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -2755,6 +2755,8 @@ static int __init acpi_match_madt(union acpi_subtable_headers *header,
return 0;
}
+void __weak arch_sort_irqchip_probe(struct acpi_probe_entry *ap_head, int nr) { }
+
int __init __acpi_probe_device_table(struct acpi_probe_entry *ap_head, int nr)
{
int count = 0;
@@ -2763,6 +2765,7 @@ int __init __acpi_probe_device_table(struct acpi_probe_entry *ap_head, int nr)
return 0;
mutex_lock(&acpi_probe_mutex);
+ arch_sort_irqchip_probe(ap_head, nr);
for (ape = ap_head; nr; ape++, nr--) {
if (ACPI_COMPARE_NAMESEG(ACPI_SIG_MADT, ape->id)) {
acpi_probe_count = 0;
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 0687a442fec7..3fff86f95c2f 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -1343,6 +1343,8 @@ struct acpi_probe_entry {
kernel_ulong_t driver_data;
};
+void arch_sort_irqchip_probe(struct acpi_probe_entry *ap_head, int nr);
+
#define ACPI_DECLARE_PROBE_ENTRY(table, name, table_id, subtable, \
valid, data, fn) \
static const struct acpi_probe_entry __acpi_probe_##name \
--
2.43.0
