diff --git a/arch/arm/mach-cns3xxx/pm.c b/arch/arm/mach-cns3xxx/pm.c
index 725e1a4..38e4470 100644
--- a/arch/arm/mach-cns3xxx/pm.c
+++ b/arch/arm/mach-cns3xxx/pm.c
@@ -6,18 +6,25 @@
  * published by the Free Software Foundation.
  */
 
+#include <linux/io.h>
 #include <linux/delay.h>
 #include <mach/system.h>
 #include <mach/cns3xxx.h>
 
 void cns3xxx_pwr_clk_en(unsigned int block)
 {
-	PM_CLK_GATE_REG |= (block & PM_CLK_GATE_REG_MASK);
+	u32 reg = __raw_readl(PM_CLK_GATE_REG);
+
+	reg |= (block & PM_CLK_GATE_REG_MASK);
+	__raw_writel(reg, PM_CLK_GATE_REG);
 }
 
 void cns3xxx_pwr_power_up(unsigned int block)
 {
-	PM_PLL_HM_PD_CTRL_REG &= ~(block & CNS3XXX_PWR_PLL_ALL);
+	u32 reg = __raw_readl(PM_PLL_HM_PD_CTRL_REG);
+
+	reg &= ~(block & CNS3XXX_PWR_PLL_ALL);
+	__raw_writel(reg, PM_PLL_HM_PD_CTRL_REG);
 
 	/* Wait for 300us for the PLL output clock locked. */
 	udelay(300);
@@ -25,22 +32,29 @@
 
 void cns3xxx_pwr_power_down(unsigned int block)
 {
+	u32 reg = __raw_readl(PM_PLL_HM_PD_CTRL_REG);
+
 	/* write '1' to power down */
-	PM_PLL_HM_PD_CTRL_REG |= (block & CNS3XXX_PWR_PLL_ALL);
+	reg |= (block & CNS3XXX_PWR_PLL_ALL);
+	__raw_writel(reg, PM_PLL_HM_PD_CTRL_REG);
 };
 
 static void cns3xxx_pwr_soft_rst_force(unsigned int block)
 {
+	u32 reg = __raw_readl(PM_SOFT_RST_REG);
+
 	/*
 	 * bit 0, 28, 29 => program low to reset,
 	 * the other else program low and then high
 	 */
 	if (block & 0x30000001) {
-		PM_SOFT_RST_REG &= ~(block & PM_SOFT_RST_REG_MASK);
+		reg &= ~(block & PM_SOFT_RST_REG_MASK);
 	} else {
-		PM_SOFT_RST_REG &= ~(block & PM_SOFT_RST_REG_MASK);
-		PM_SOFT_RST_REG |= (block & PM_SOFT_RST_REG_MASK);
+		reg &= ~(block & PM_SOFT_RST_REG_MASK);
+		reg |= (block & PM_SOFT_RST_REG_MASK);
 	}
+
+	__raw_writel(reg, PM_SOFT_RST_REG);
 }
 
 void cns3xxx_pwr_soft_rst(unsigned int block)
@@ -73,12 +87,13 @@
  */
 int cns3xxx_cpu_clock(void)
 {
+	u32 reg = __raw_readl(PM_CLK_CTRL_REG);
 	int cpu;
 	int cpu_sel;
 	int div_sel;
 
-	cpu_sel = (PM_CLK_CTRL_REG >> PM_CLK_CTRL_REG_OFFSET_PLL_CPU_SEL) & 0xf;
-	div_sel = (PM_CLK_CTRL_REG >> PM_CLK_CTRL_REG_OFFSET_CPU_CLK_DIV) & 0x3;
+	cpu_sel = (reg >> PM_CLK_CTRL_REG_OFFSET_PLL_CPU_SEL) & 0xf;
+	div_sel = (reg >> PM_CLK_CTRL_REG_OFFSET_CPU_CLK_DIV) & 0x3;
 
 	cpu = (300 + ((cpu_sel / 3) * 100) + ((cpu_sel % 3) * 33)) >> div_sel;