diff --git a/include/zephyr/xen/public/hvm/params.h b/include/zephyr/xen/public/hvm/params.h
index 1222b2ffdefda6c..dcd79a1673cf58e 100644
--- a/include/zephyr/xen/public/hvm/params.h
+++ b/include/zephyr/xen/public/hvm/params.h
@@ -33,6 +33,7 @@
  */
 #define HVM_PARAM_STORE_PFN		1
 #define HVM_PARAM_STORE_EVTCHN		2
+#define HVM_PARAM_MAGIC_BASE_PFN	3
 
 /* Console debug shared memory ring and event channel */
 #define HVM_PARAM_CONSOLE_PFN		17