diff --git a/lib/libc/memcmp.c b/lib/libc/memcmp.c
new file mode 100644
index 0000000..a4c798b
--- /dev/null
+++ b/lib/libc/memcmp.c
@@ -0,0 +1,24 @@
+/*
+ * Copyright (c) 2013-2018, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <stddef.h>
+
+int memcmp(const void *s1, const void *s2, size_t len)
+{
+	const unsigned char *s = s1;
+	const unsigned char *d = s2;
+	unsigned char sc;
+	unsigned char dc;
+
+	while (len--) {
+		sc = *s++;
+		dc = *d++;
+		if (sc - dc)
+			return (sc - dc);
+	}
+
+	return 0;
+}