[PATCH 1/4] ACPI / processor : add support for ACPI0010 processor container

[Sudeep Holla <sudeep.holla@arm.com>]

ACPI 6.0 adds support for optional processor container device which may
contain child objects that are either processor devices or other processor
containers. This allows representing hierarchical processor topologies.

It is declared using the _HID of ACPI0010. It is an abstract container
used to represent CPU topology and should not be used to hotplug
purposes.

This patch enables the support for these ACPI processor containers and
ensures the generic container/module devices are not created for them.

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
---
 drivers/acpi/acpi_processor.c | 17 +++++++++++++++++
 include/acpi/processor.h      |  1 +
 2 files changed, 18 insertions(+)

diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c
index 92a5f738e370..921948b34571 100644
--- a/drivers/acpi/acpi_processor.c
+++ b/drivers/acpi/acpi_processor.c
@@ -496,7 +496,24 @@ static struct acpi_scan_handler __refdata processor_handler = {
 	},
 };
 
+static int acpi_processor_container_attach(struct acpi_device *dev,
+					   const struct acpi_device_id *id)
+{
+	return 1;
+}
+
+static const struct acpi_device_id processor_container_ids[] = {
+	{ ACPI_PROCESSOR_CONTAINER_HID, },
+	{ }
+};
+
+static struct acpi_scan_handler processor_container_handler = {
+	.ids = processor_container_ids,
+	.attach = acpi_processor_container_attach,
+};
+
 void __init acpi_processor_init(void)
 {
 	acpi_scan_add_handler_with_hotplug(&processor_handler, "processor");
+	acpi_scan_add_handler(&processor_container_handler);
 }
diff --git a/include/acpi/processor.h b/include/acpi/processor.h
index 4188a4d3b597..2669cae4a0c8 100644
--- a/include/acpi/processor.h
+++ b/include/acpi/processor.h
@@ -9,6 +9,7 @@
 #define ACPI_PROCESSOR_CLASS		"processor"
 #define ACPI_PROCESSOR_DEVICE_NAME	"Processor"
 #define ACPI_PROCESSOR_DEVICE_HID	"ACPI0007"
+#define ACPI_PROCESSOR_CONTAINER_HID	"ACPI0010"
 
 #define ACPI_PROCESSOR_BUSY_METRIC	10
 
-- 
1.9.1