diff --git a/arch/arm/plat-s3c64xx/irq.c b/arch/arm/plat-s3c64xx/irq.c
index a94f1d5e819d..f22edf7c2d2d 100644
--- a/arch/arm/plat-s3c64xx/irq.c
+++ b/arch/arm/plat-s3c64xx/irq.c
@@ -207,7 +207,7 @@ static struct irq_chip s3c_irq_uart = {
 
 static void __init s3c64xx_uart_irq(struct uart_irq *uirq)
 {
-	void *reg_base = uirq->regs;
+	void __iomem *reg_base = uirq->regs;
 	unsigned int irq;
 	int offs;