diff --git a/doc/developer-guides/hld/hv-timer.rst b/doc/developer-guides/hld/hv-timer.rst
index b31e3ace3..a5f1ebd2c 100644
--- a/doc/developer-guides/hld/hv-timer.rst
+++ b/doc/developer-guides/hld/hv-timer.rst
@@ -59,3 +59,9 @@ Interfaces Design
 
 .. doxygenfunction:: get_tsc_khz
    :project: Project ACRN
+
+.. doxygenfunction:: timer_is_started
+   :project: Project ACRN
+
+.. doxygenfunction:: udelay
+   :project: Project ACRN