diff --git a/arch/arm64/include/irq.h b/arch/arm64/include/irq.h
index 7467691a288..485d70492fb 100644
--- a/arch/arm64/include/irq.h
+++ b/arch/arm64/include/irq.h
@@ -154,10 +154,11 @@
 #define REG_SP_EL0          (34)
 #define REG_EXE_DEPTH       (35)
 #define REG_SCTLR_EL1       (36)
+#define REG_RESERVED        (37)
 
 /* In Armv8-A Architecture, the stack must align with 16 byte */
 
-#define ARM64_CONTEXT_REGS  (37)
+#define ARM64_CONTEXT_REGS  (38)
 #define ARM64_CONTEXT_SIZE  (8 * ARM64_CONTEXT_REGS)
 
 #ifdef CONFIG_ARCH_FPU