diff --git a/arch/sh/include/asm/irq.h b/arch/sh/include/asm/irq.h
index d319baaf4fbd..a2b8c99cc06f 100644
--- a/arch/sh/include/asm/irq.h
+++ b/arch/sh/include/asm/irq.h
@@ -8,7 +8,8 @@
  * advised to cap this at the hard limit that they're interested in
  * through the machvec.
  */
-#define NR_IRQS 256
+#define NR_IRQS			256
+#define NR_IRQS_LEGACY		8	/* Legacy external IRQ0-7 */
 
 /*
  * Convert back and forth between INTEVT and IRQ values.