diff --git a/boards/xtensa/esp32s3/esp32s3-devkit/src/esp32s3_bringup.c b/boards/xtensa/esp32s3/esp32s3-devkit/src/esp32s3_bringup.c
index 4c243a7b009..8813a64d156 100644
--- a/boards/xtensa/esp32s3/esp32s3-devkit/src/esp32s3_bringup.c
+++ b/boards/xtensa/esp32s3/esp32s3-devkit/src/esp32s3_bringup.c
@@ -42,6 +42,10 @@
 #  include "esp32s3_board_tim.h"
 #endif
 
+#ifdef CONFIG_ESP32S3_RT_TIMER
+#  include "esp32s3_rt_timer.h"
+#endif
+
 #ifdef CONFIG_WATCHDOG
 #  include "esp32s3_board_wdt.h"
 #endif
@@ -101,6 +105,14 @@ int esp32s3_bringup(void)
     }
 #endif
 
+#ifdef CONFIG_ESP32S3_RT_TIMER
+  ret = esp32s3_rt_timer_init();
+  if (ret < 0)
+    {
+      syslog(LOG_ERR, "Failed to initialize RT timer: %d\n", ret);
+    }
+#endif
+
 #ifdef CONFIG_WATCHDOG
   /* Configure watchdog timer */