v4.19.13 snapshot.
diff --git a/arch/sparc/include/asm/mdesc.h b/arch/sparc/include/asm/mdesc.h
new file mode 100644
index 0000000..ec31a06
--- /dev/null
+++ b/arch/sparc/include/asm/mdesc.h
@@ -0,0 +1,99 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _SPARC64_MDESC_H
+#define _SPARC64_MDESC_H
+
+#include <linux/types.h>
+#include <linux/cpumask.h>
+#include <asm/prom.h>
+
+struct mdesc_handle;
+
+/* Machine description operations are to be surrounded by grab and
+ * release calls. The mdesc_handle returned from the grab is
+ * the first argument to all of the operational calls that work
+ * on mdescs.
+ */
+struct mdesc_handle *mdesc_grab(void);
+void mdesc_release(struct mdesc_handle *);
+
+#define MDESC_NODE_NULL (~(u64)0)
+#define MDESC_MAX_STR_LEN 256
+
+u64 mdesc_node_by_name(struct mdesc_handle *handle,
+ u64 from_node, const char *name);
+#define mdesc_for_each_node_by_name(__hdl, __node, __name) \
+ for (__node = mdesc_node_by_name(__hdl, MDESC_NODE_NULL, __name); \
+ (__node) != MDESC_NODE_NULL; \
+ __node = mdesc_node_by_name(__hdl, __node, __name))
+
+/* Access to property values returned from mdesc_get_property() are
+ * only valid inside of a mdesc_grab()/mdesc_release() sequence.
+ * Once mdesc_release() is called, the memory backed up by these
+ * pointers may reference freed up memory.
+ *
+ * Therefore callers must make copies of any property values
+ * they need.
+ *
+ * These same rules apply to mdesc_node_name().
+ */
+const void *mdesc_get_property(struct mdesc_handle *handle,
+ u64 node, const char *name, int *lenp);
+const char *mdesc_node_name(struct mdesc_handle *hp, u64 node);
+
+/* MD arc iteration, the standard sequence is:
+ *
+ * unsigned long arc;
+ * mdesc_for_each_arc(arc, handle, node, MDESC_ARC_TYPE_{FWD,BACK}) {
+ * unsigned long target = mdesc_arc_target(handle, arc);
+ * ...
+ * }
+ */
+
+#define MDESC_ARC_TYPE_FWD "fwd"
+#define MDESC_ARC_TYPE_BACK "back"
+
+u64 mdesc_next_arc(struct mdesc_handle *handle, u64 from,
+ const char *arc_type);
+#define mdesc_for_each_arc(__arc, __hdl, __node, __type) \
+ for (__arc = mdesc_next_arc(__hdl, __node, __type); \
+ (__arc) != MDESC_NODE_NULL; \
+ __arc = mdesc_next_arc(__hdl, __arc, __type))
+
+u64 mdesc_arc_target(struct mdesc_handle *hp, u64 arc);
+
+void mdesc_update(void);
+
+struct mdesc_notifier_client {
+ void (*add)(struct mdesc_handle *handle, u64 node,
+ const char *node_name);
+ void (*remove)(struct mdesc_handle *handle, u64 node,
+ const char *node_name);
+ const char *node_name;
+ struct mdesc_notifier_client *next;
+};
+
+void mdesc_register_notifier(struct mdesc_notifier_client *client);
+
+union md_node_info {
+ struct vdev_port {
+ u64 id; /* id */
+ u64 parent_cfg_hdl; /* parent config handle */
+ const char *name; /* name (property) */
+ } vdev_port;
+ struct ds_port {
+ u64 id; /* id */
+ } ds_port;
+};
+
+u64 mdesc_get_node(struct mdesc_handle *hp, const char *node_name,
+ union md_node_info *node_info);
+int mdesc_get_node_info(struct mdesc_handle *hp, u64 node,
+ const char *node_name, union md_node_info *node_info);
+
+void mdesc_fill_in_cpu_data(cpumask_t *mask);
+void mdesc_populate_present_mask(cpumask_t *mask);
+void mdesc_get_page_sizes(cpumask_t *mask, unsigned long *pgsz_mask);
+
+void sun4v_mdesc_init(void);
+
+#endif