diff --git a/plat/st/common/stm32mp_dt.c b/plat/st/common/stm32mp_dt.c
index 4fa796f..a8119ae 100644
--- a/plat/st/common/stm32mp_dt.c
+++ b/plat/st/common/stm32mp_dt.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017-2019, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2017-2020, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -92,6 +92,7 @@
 	return status;
 }
 
+#if ENABLE_ASSERTIONS
 /*******************************************************************************
  * This function returns the address cells from the node parent.
  * Returns:
@@ -100,7 +101,7 @@
  * - a default value if undefined #address-cells property as per libfdt
  *   implementation.
  ******************************************************************************/
-int fdt_get_node_parent_address_cells(int node)
+static int fdt_get_node_parent_address_cells(int node)
 {
 	int parent;
 
@@ -120,7 +121,7 @@
  * - a default value if undefined #size-cells property as per libfdt
  *   implementation.
  ******************************************************************************/
-int fdt_get_node_parent_size_cells(int node)
+static int fdt_get_node_parent_size_cells(int node)
 {
 	int parent;
 
@@ -131,6 +132,7 @@
 
 	return fdt_size_cells(fdt, parent);
 }
+#endif
 
 /*******************************************************************************
  * This function reads a value of a node property (generic use of fdt