diff --git a/include/arch/aarch64/arch.h b/include/arch/aarch64/arch.h
index 627416f..67fdead 100644
--- a/include/arch/aarch64/arch.h
+++ b/include/arch/aarch64/arch.h
@@ -1585,4 +1585,11 @@
 #define CLUSTERPMCR_N_SHIFT		U(11)
 #define CLUSTERPMCR_N_MASK		U(0x1f)
 
+/*******************************************************************************
+ * FEAT_MEC - Memory Encryption Contexts
+ ******************************************************************************/
+#define MECIDR_EL2			S3_4_C10_C8_7
+#define MECIDR_EL2_MECIDWidthm1_MASK	U(0xf)
+#define MECIDR_EL2_MECIDWidthm1_SHIFT	U(0)
+
 #endif /* ARCH_H */
diff --git a/include/arch/aarch64/arch_helpers.h b/include/arch/aarch64/arch_helpers.h
index f85da97..55b6199 100644
--- a/include/arch/aarch64/arch_helpers.h
+++ b/include/arch/aarch64/arch_helpers.h
@@ -746,6 +746,9 @@
 
 DEFINE_RENAME_SYSREG_RW_FUNCS(fpmr, FPMR)
 
+/* FEAT_MEC Registers */
+DEFINE_RENAME_SYSREG_READ_FUNC(mecidr_el2, MECIDR_EL2)
+
 #define IS_IN_EL(x) \
 	(GET_EL(read_CurrentEl()) == MODE_EL##x)