diff --git a/os/common/ports/ARMCAx-TZ/chsmc.h b/os/common/ports/ARMCAx-TZ/chsmc.h
index bd22b2e94..4acab838b 100644
--- a/os/common/ports/ARMCAx-TZ/chsmc.h
+++ b/os/common/ports/ARMCAx-TZ/chsmc.h
@@ -83,6 +83,7 @@ CC_NO_RETURN void _ns_trampoline(uint32_t addr);
 void smcInit(void);
 msg_t smc_entry(msg_t svc_number, void *svc_data);
 registered_object_t * smcRegisterMeAsService(const char *svc_name);
+msg_t smcServiceWaitRequest(smc_service_t *svcp);
 #ifdef __cplusplus
 }
 #endif