diff --git a/arch/arm/mach-ns9xxx/irq.c b/arch/arm/mach-ns9xxx/irq.c
index 24d424e..00001b8 100644
--- a/arch/arm/mach-ns9xxx/irq.c
+++ b/arch/arm/mach-ns9xxx/irq.c
@@ -9,6 +9,7 @@
  * the Free Software Foundation.
  */
 #include <linux/interrupt.h>
+#include <asm/io.h>
 #include <asm/mach/irq.h>
 #include <asm/mach-types.h>
 #include <asm/arch-ns9xxx/regs-sys.h>
@@ -20,12 +21,14 @@
 static void ns9xxx_mask_irq(unsigned int irq)
 {
 	/* XXX: better use cpp symbols */
-	SYS_IC(irq / 4) &= ~(1 << (7 + 8 * (3 - (irq & 3))));
+	u32 ic = __raw_readl(SYS_IC(irq / 4));
+	ic &= ~(1 << (7 + 8 * (3 - (irq & 3))));
+	__raw_writel(ic, SYS_IC(irq / 4));
 }
 
 static void ns9xxx_ack_irq(unsigned int irq)
 {
-	SYS_ISRADDR = 0;
+	__raw_writel(0, SYS_ISRADDR);
 }
 
 static void ns9xxx_maskack_irq(unsigned int irq)
@@ -37,7 +40,9 @@
 static void ns9xxx_unmask_irq(unsigned int irq)
 {
 	/* XXX: better use cpp symbols */
-	SYS_IC(irq / 4) |= 1 << (7 + 8 * (3 - (irq & 3)));
+	u32 ic = __raw_readl(SYS_IC(irq / 4));
+	ic |= 1 << (7 + 8 * (3 - (irq & 3)));
+	__raw_writel(ic, SYS_IC(irq / 4));
 }
 
 static struct irq_chip ns9xxx_chip = {
@@ -53,14 +58,14 @@
 
 	/* disable all IRQs */
 	for (i = 0; i < 8; ++i)
-		SYS_IC(i) = (4 * i) << 24 | (4 * i + 1) << 16 |
-			(4 * i + 2) << 8 | (4 * i + 3);
+		__raw_writel((4 * i) << 24 | (4 * i + 1) << 16 |
+				(4 * i + 2) << 8 | (4 * i + 3), SYS_IC(i));
 
 	/* simple interrupt prio table:
 	 * prio(x) < prio(y) <=> x < y
 	 */
 	for (i = 0; i < 32; ++i)
-		SYS_IVA(i) = i;
+		__raw_writel(i, SYS_IVA(i));
 
 	for (i = IRQ_WATCHDOG; i <= IRQ_EXT3; ++i) {
 		set_irq_chip(i, &ns9xxx_chip);