diff --git a/sim/src/utils.rs b/sim/src/utils.rs
new file mode 100644
index 0000000..abbac3c
--- /dev/null
+++ b/sim/src/utils.rs
@@ -0,0 +1,11 @@
+// SPDX-FileCopyrightText: 2021 Espressif Systems (Shanghai) CO LTD
+//
+// SPDX-License-Identifier: Apache-2.0
+
+//! Utility functions used throughout MCUboot
+
+pub fn align_up(num: u32, align: u32) -> u32 {
+    assert!(align.is_power_of_two());
+
+    (num + (align - 1)) & !(align - 1)
+}