[RFC part2 PATCH 3/9] ARM64 / ACPI: Introduce map_gic_id() to get apic id from MADT or _MAT method

Hanjun Guo
2013-12-03T16:40:18Z

Get apic id from MADT or _MAT method is not implemented on arm/arm64,
and ACPI 5.0 introduces GIC Structure for it, so this patch introduces
map_gic_id() to get apic id followed the ACPI 5.0 spec.

Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
---
drivers/acpi/processor_core.c | 26 ++++++++++++++++++++++++++
1 file changed, 26 insertions(+)

diff --git a/drivers/acpi/processor_core.c b/drivers/acpi/processor_core.c
index 9931435..a83b01c 100644
--- a/drivers/acpi/processor_core.c
+++ b/drivers/acpi/processor_core.c
@@ -89,6 +89,27 @@ static int map_lsapic_id(struct acpi_subtable_header *entry,
return 1;
}

+static int map_gic_id(struct acpi_subtable_header *entry,
+ int device_declaration, u32 acpi_id, int *apic_id)
+{
+ struct acpi_madt_generic_interrupt *gic =
+ (struct acpi_madt_generic_interrupt *)entry;
+
+ if (!(gic->flags & ACPI_MADT_ENABLED))
+ return 0;
+
+ /* In the GIC interrupt model, logical processors are
+ * required to have a Processor Device object in the DSDT,
+ * so we should check device_declaration here
+ */
+ if (device_declaration && (gic->uid == acpi_id)) {
+ *apic_id = gic->gic_id;
+ return 1;
+ }
+
+ return 0;
+}
+
static int map_madt_entry(int type, u32 acpi_id)
{
unsigned long madt_end, entry;
@@ -124,6 +145,9 @@ static int map_madt_entry(int type, u32 acpi_id)
} else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
if (map_lsapic_id(header, type, acpi_id, &apic_id))
break;
+ } else if (header->type == ACPI_MADT_TYPE_GENERIC_INTERRUPT) {
+ if (map_gic_id(header, type, acpi_id, &apic_id))
+ break;
}
entry += header->length;
}
@@ -154,6 +178,8 @@ static int map_mat_entry(acpi_handle handle, int type, u32 acpi_id)
map_lapic_id(header, acpi_id, &apic_id);
} else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
map_lsapic_id(header, type, acpi_id, &apic_id);
+ } else if (header->type == ACPI_MADT_TYPE_GENERIC_INTERRUPT) {
+ map_gic_id(header, type, acpi_id, &apic_id);
}

exit:
--
1.7.9.5