v4.19.13 snapshot.
diff --git a/arch/arc/include/asm/mmzone.h b/arch/arc/include/asm/mmzone.h
new file mode 100644
index 0000000..8e97136
--- /dev/null
+++ b/arch/arc/include/asm/mmzone.h
@@ -0,0 +1,43 @@
+/*
+ * Copyright (C) 2016 Synopsys, Inc. (www.synopsys.com)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _ASM_ARC_MMZONE_H
+#define _ASM_ARC_MMZONE_H
+
+#ifdef CONFIG_DISCONTIGMEM
+
+extern struct pglist_data node_data[];
+#define NODE_DATA(nid) (&node_data[nid])
+
+static inline int pfn_to_nid(unsigned long pfn)
+{
+	int is_end_low = 1;
+
+	if (IS_ENABLED(CONFIG_ARC_HAS_PAE40))
+		is_end_low = pfn <= virt_to_pfn(0xFFFFFFFFUL);
+
+	/*
+	 * node 0: lowmem:             0x8000_0000   to 0xFFFF_FFFF
+	 * node 1: HIGHMEM w/o  PAE40: 0x0           to 0x7FFF_FFFF
+	 *         HIGHMEM with PAE40: 0x1_0000_0000 to ...
+	 */
+	if (pfn >= ARCH_PFN_OFFSET && is_end_low)
+		return 0;
+
+	return 1;
+}
+
+static inline int pfn_valid(unsigned long pfn)
+{
+	int nid = pfn_to_nid(pfn);
+
+	return (pfn <= node_end_pfn(nid));
+}
+#endif /* CONFIG_DISCONTIGMEM  */
+
+#endif