diff --git a/include/acpi/actbl3.h b/include/acpi/actbl3.h
index 9125e2f16329..edbf1ad8206d 100644
--- a/include/acpi/actbl3.h
+++ b/include/acpi/actbl3.h
@@ -191,7 +191,8 @@ enum acpi_srat_type {
 	ACPI_SRAT_TYPE_GICC_AFFINITY = 3,
 	ACPI_SRAT_TYPE_GIC_ITS_AFFINITY = 4,	/* ACPI 6.2 */
 	ACPI_SRAT_TYPE_GENERIC_AFFINITY = 5,	/* ACPI 6.3 */
-	ACPI_SRAT_TYPE_RESERVED = 6	/* 5 and greater are reserved */
+	ACPI_SRAT_TYPE_GENERIC_PORT_AFFINITY = 6,	/* ACPI 6.4 */
+	ACPI_SRAT_TYPE_RESERVED = 7	/* 7 and greater are reserved */
 };
 
 /*
@@ -272,7 +273,11 @@ struct acpi_srat_gic_its_affinity {
 	u32 its_id;
 };
 
-/* 5: Generic Initiator Affinity Structure (ACPI 6.3) */
+/*
+ * Common structure for SRAT subtable types:
+ * 5: ACPI_SRAT_TYPE_GENERIC_AFFINITY
+ * 6: ACPI_SRAT_TYPE_GENERIC_PORT_AFFINITY
+ */
 
 struct acpi_srat_generic_affinity {
 	struct acpi_subtable_header header;