diff --git a/arch/Kconfig b/arch/Kconfig
index accd4df..356193f 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -147,6 +147,7 @@
 	imply CMD_PMC
 	imply CMD_CLONE
 	imply SILENT_CONSOLE
+	imply BOOTARGS_SUBST
 
 config SH
 	bool "SuperH architecture"