1 files changed, 26 insertions, 0 deletions

diff --git a/drivers/acpi/pptt.c b/drivers/acpi/pptt.c
index 05344413f199..1e7ac0bd0d3a 100644
--- a/drivers/acpi/pptt.c
+++ b/drivers/acpi/pptt.c
@@ -683,3 +683,29 @@ int find_acpi_cpu_topology_package(unsigned int cpu)
         return find_acpi_cpu_topology_tag(cpu, PPTT_ABORT_PACKAGE,
                                           ACPI_PPTT_PHYSICAL_PACKAGE);
 }
+
+/**
+ * find_acpi_cpu_topology_hetero_id() - Get a core architecture tag
+ * @cpu: Kernel logical CPU number
+ *
+ * Determine a unique heterogeneous tag for the given CPU. CPUs with the same
+ * implementation should have matching tags.
+ *
+ * The returned tag can be used to group peers with identical implementation.
+ *
+ * The search terminates when a level is found with the identical implementation
+ * flag set or we reach a root node.
+ *
+ * Due to limitations in the PPTT data structure, there may be rare situations
+ * where two cores in a heterogeneous machine may be identical, but won't have
+ * the same tag.
+ *
+ * Return: -ENOENT if the PPTT doesn't exist, or the CPU cannot be found.
+ * Otherwise returns a value which represents a group of identical cores
+ * similar to this CPU.
+ */
+int find_acpi_cpu_topology_hetero_id(unsigned int cpu)
+{
+        return find_acpi_cpu_topology_tag(cpu, PPTT_ABORT_PACKAGE,
+                                          ACPI_PPTT_ACPI_IDENTICAL);
+}