diff --git a/arch/arm/mach-mx5/clock-mx51-mx53.c b/arch/arm/mach-mx5/clock-mx51-mx53.c
index 7f20308..f7bf996 100644
--- a/arch/arm/mach-mx5/clock-mx51-mx53.c
+++ b/arch/arm/mach-mx5/clock-mx51-mx53.c
@@ -271,7 +271,11 @@ static int _clk_pll_enable(struct clk *clk)
 	int i = 0;
 
 	pllbase = _get_pll_base(clk);
-	reg = __raw_readl(pllbase + MXC_PLL_DP_CTL) | MXC_PLL_DP_CTL_UPEN;
+	reg = __raw_readl(pllbase + MXC_PLL_DP_CTL);
+	if (reg & MXC_PLL_DP_CTL_UPEN)
+		return 0;
+
+	reg |= MXC_PLL_DP_CTL_UPEN;
 	__raw_writel(reg, pllbase + MXC_PLL_DP_CTL);
 
 	/* Wait for lock */