diff --git a/lib/extensions/amu/aarch64/amu.c b/lib/extensions/amu/aarch64/amu.c
new file mode 100644
index 0000000..007b349
--- /dev/null
+++ b/lib/extensions/amu/aarch64/amu.c
@@ -0,0 +1,40 @@
+/*
+ * Copyright (c) 2017, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <amu.h>
+#include <arch.h>
+#include <arch_helpers.h>
+
+void amu_enable(int el2_unused)
+{
+	uint64_t features;
+
+	features = read_id_aa64pfr0_el1() >> ID_AA64PFR0_AMU_SHIFT;
+	if ((features & ID_AA64PFR0_AMU_MASK) == 1) {
+		uint64_t v;
+
+		if (el2_unused) {
+			/*
+			 * CPTR_EL2.TAM: Set to zero so any accesses to
+			 * the Activity Monitor registers do not trap to EL2.
+			 */
+			v = read_cptr_el2();
+			v &= ~CPTR_EL2_TAM_BIT;
+			write_cptr_el2(v);
+		}
+
+		/*
+		 * CPTR_EL3.TAM: Set to zero so that any accesses to
+		 * the Activity Monitor registers do not trap to EL3.
+		 */
+		v = read_cptr_el3();
+		v &= ~TAM_BIT;
+		write_cptr_el3(v);
+
+		/* Enable group 0 counters */
+		write_amcntenset0_el0(AMU_GROUP0_COUNTERS_MASK);
+	}
+}