diff --git a/arch/sh/cpu/sh3/config.mk b/arch/sh/cpu/sh3/config.mk
index 5c77e5c..abd4b8d 100644
--- a/arch/sh/cpu/sh3/config.mk
+++ b/arch/sh/cpu/sh3/config.mk
@@ -11,5 +11,5 @@
 # SPDX-License-Identifier:	GPL-2.0+
 #
 #
-PLATFORM_CPPFLAGS += -m3
+PLATFORM_CPPFLAGS += -DCONFIG_SH3 -m3
 PLATFORM_RELFLAGS += -ffixed-r13