diff --git a/arch/arm/include/asm/arch-imx9/mu.h b/arch/arm/include/asm/arch-imx9/mu.h
new file mode 100644
index 0000000..b860499
--- /dev/null
+++ b/arch/arm/include/asm/arch-imx9/mu.h
@@ -0,0 +1,13 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright (C) 2024 Mathieu Othacehe <m.othacehe@gmail.com>
+ */
+
+#ifndef __ARCH_IMX9_MU_H
+#define __ARCH_IMX9_MU_H
+
+#include <event.h>
+
+int imx9_probe_mu(void *ctx, struct event *event);
+
+#endif
diff --git a/board/freescale/imx93_evk/spl.c b/board/freescale/imx93_evk/spl.c
index be9c24f..a98ed69 100644
--- a/board/freescale/imx93_evk/spl.c
+++ b/board/freescale/imx93_evk/spl.c
@@ -14,6 +14,7 @@
 #include <asm/global_data.h>
 #include <asm/io.h>
 #include <asm/arch/imx93_pins.h>
+#include <asm/arch/mu.h>
 #include <asm/arch/clock.h>
 #include <asm/arch/sys_proto.h>
 #include <asm/mach-imx/boot_mode.h>
@@ -91,7 +92,6 @@
 }
 #endif
 
-extern int imx9_probe_mu(void *ctx, struct event *event);
 void board_init_f(ulong dummy)
 {
 	int ret;
diff --git a/board/phytec/phycore_imx93/spl.c b/board/phytec/phycore_imx93/spl.c
index da4b9e5..dabc531 100644
--- a/board/phytec/phycore_imx93/spl.c
+++ b/board/phytec/phycore_imx93/spl.c
@@ -7,6 +7,7 @@
 
 #include <asm/arch/clock.h>
 #include <asm/arch/ddr.h>
+#include <asm/arch/mu.h>
 #include <asm/arch/sys_proto.h>
 #include <asm/arch/trdc.h>
 #include <asm/mach-imx/boot_mode.h>
@@ -99,7 +100,6 @@
 	return 0;
 }
 
-extern int imx9_probe_mu(void *ctx, struct event *event);
 void board_init_f(ulong dummy)
 {
 	int ret;