diff --git a/drivers/mbox/Kconfig b/drivers/mbox/Kconfig
index 05874a41a53..30654c62d25 100644
--- a/drivers/mbox/Kconfig
+++ b/drivers/mbox/Kconfig
@@ -9,20 +9,16 @@ menuconfig MBOX
 
 if MBOX
 
+# Include these first so that any properties (e.g. defaults) below can be
+# overridden (by defining symbols in multiple locations)
+source "drivers/mbox/Kconfig.nrfx"
+
 config MBOX_INIT_PRIORITY
 	int "MBOX init priority"
 	default KERNEL_INIT_PRIORITY_DEVICE
 	help
 	  MBOX driver device initialization priority.
 
-config MBOX_NRFX_IPC
-	bool "MBOX NRF IPC driver"
-	depends on HAS_HW_NRF_IPC
-	select NRFX_IPC
-	help
-	  Driver for Nordic nRF messaging unit, based
-	  on nRF IPC peripheral HW.
-
 module = MBOX
 module-str = mbox
 source "subsys/logging/Kconfig.template.log_config"
diff --git a/drivers/mbox/Kconfig.nrfx b/drivers/mbox/Kconfig.nrfx
new file mode 100644
index 00000000000..70aefd8241f
--- /dev/null
+++ b/drivers/mbox/Kconfig.nrfx
@@ -0,0 +1,10 @@
+# Copyright (c) 2021 Carlo Caione <ccaione@baylibre.com>
+# SPDX-License-Identifier: Apache-2.0
+
+config MBOX_NRFX_IPC
+	bool "MBOX NRF IPC driver"
+	depends on HAS_HW_NRF_IPC
+	select NRFX_IPC
+	help
+	  Driver for Nordic nRF messaging unit, based
+	  on nRF IPC peripheral HW.