diff --git a/boot/cypress/MCUBootApp/config/mcuboot_config/mcuboot_config.h b/boot/cypress/MCUBootApp/config/mcuboot_config/mcuboot_config.h
index a58d584b..e18d0fb6 100644
--- a/boot/cypress/MCUBootApp/config/mcuboot_config/mcuboot_config.h
+++ b/boot/cypress/MCUBootApp/config/mcuboot_config/mcuboot_config.h
@@ -152,4 +152,11 @@
 #define NUM_ECC_BYTES (256 / 8)
 #endif /* ENC_IMG */
 
+/*
+ * No direct idle call implemented
+ */
+#define MCUBOOT_CPU_IDLE() \
+    do {                   \
+    } while (0)
+
 #endif /* MCUBOOT_CONFIG_H */
diff --git a/boot/mbed/include/mcuboot_config/mcuboot_config.h b/boot/mbed/include/mcuboot_config/mcuboot_config.h
index 468d8ee4..a603e05d 100644
--- a/boot/mbed/include/mcuboot_config/mcuboot_config.h
+++ b/boot/mbed/include/mcuboot_config/mcuboot_config.h
@@ -79,5 +79,11 @@
     do {                                        \
     } while (0)
 
+/*
+ * No direct idle call implemented
+ */
+#define MCUBOOT_CPU_IDLE() \
+    do {                   \
+    } while (0)
 
 #endif /* __MCUBOOT_CONFIG_H__ */
diff --git a/boot/mynewt/mcuboot_config/include/mcuboot_config/mcuboot_config.h b/boot/mynewt/mcuboot_config/include/mcuboot_config/mcuboot_config.h
index 696f2e70..4c0ec387 100644
--- a/boot/mynewt/mcuboot_config/include/mcuboot_config/mcuboot_config.h
+++ b/boot/mynewt/mcuboot_config/include/mcuboot_config/mcuboot_config.h
@@ -101,4 +101,11 @@
 #define MCUBOOT_WATCHDOG_FEED()    do {} while (0)
 #endif
 
+/*
+ * No direct idle call implemented
+ */
+#define MCUBOOT_CPU_IDLE() \
+    do {                   \
+    } while (0)
+
 #endif /* __MCUBOOT_CONFIG_H__ */
diff --git a/boot/zephyr/include/mcuboot_config/mcuboot_config.h b/boot/zephyr/include/mcuboot_config/mcuboot_config.h
index 8f2b1575..13a28e68 100644
--- a/boot/zephyr/include/mcuboot_config/mcuboot_config.h
+++ b/boot/zephyr/include/mcuboot_config/mcuboot_config.h
@@ -205,4 +205,9 @@
 
 #endif /* CONFIG_BOOT_WATCHDOG_FEED */
 
+#define MCUBOOT_CPU_IDLE() \
+  if (!IS_ENABLED(CONFIG_MULTITHREADING)) { \
+    k_cpu_idle(); \
+  }
+
 #endif /* __MCUBOOT_CONFIG_H__ */
diff --git a/samples/mcuboot_config/mcuboot_config.template.h b/samples/mcuboot_config/mcuboot_config.template.h
index 2125792d..989ec618 100644
--- a/samples/mcuboot_config/mcuboot_config.template.h
+++ b/samples/mcuboot_config/mcuboot_config.template.h
@@ -146,4 +146,14 @@
  *    do { do watchdog feeding here! } while (0)
  */
 
+/* If a OS ports support single thread mode or is bare-metal then:
+ * This macro implements call that switches CPU to an idle state, from which
+ * the CPU may be woken up by, for example, UART transmission event.
+ * 
+ * Otherwise this macro should be no-op.
+ */
+#define MCUBOOT_CPU_IDLE() \
+    do {                   \
+    } while (0)
+
 #endif /* __MCUBOOT_CONFIG_H__ */