diff --git a/litex/soc/software/bios/commands/cmd_mdio.c b/litex/soc/software/bios/commands/cmd_mdio.c
index 9d28c5347..35b020737 100644
--- a/litex/soc/software/bios/commands/cmd_mdio.c
+++ b/litex/soc/software/bios/commands/cmd_mdio.c
@@ -5,6 +5,8 @@
 
 #include <generated/csr.h>
 
+#include <base/mdio.h>
+
 #include "../command.h"
 #include "../helpers.h"