1 files changed, 12 insertions, 4 deletions

diff --git a/arch/arm/mach-tcc8k/clock.c b/arch/arm/mach-tcc8k/clock.c
index 3970a9cdce26..7ebcbff4652a 100644
--- a/arch/arm/mach-tcc8k/clock.c
+++ b/arch/arm/mach-tcc8k/clock.c
@@ -50,6 +50,8 @@
 #define ACLKTCX         (CKC_BASE + ACLKTCX_OFFS)
 #define ACLKTCZ         (CKC_BASE + ACLKTCZ_OFFS)
 
+#define ACLK_MAX_DIV    (0xfff + 1)
+
 /* Crystal frequencies */
 static unsigned long xi_rate, xti_rate;
 
@@ -258,14 +260,19 @@ static unsigned long aclk_best_div(struct clk *clk, unsigned long rate)
 {
         unsigned long div, src, freq, r1, r2;
 
+        if (!rate)
+                return ACLK_MAX_DIV;
+
         src = __raw_readl(clk->aclkreg) >> ACLK_SEL_SHIFT;
         src &= CLK_SRC_MASK;
         freq = root_clk_get_rate(src);
-        div = freq / rate + 1;
+        div = freq / rate;
+        if (!div)
+                return 1;
+        if (div >= ACLK_MAX_DIV)
+                return ACLK_MAX_DIV;
         r1 = freq / div;
         r2 = freq / (div + 1);
-        if (r2 >= rate)
-                return div + 1;
         if ((rate - r2) < (r1 - rate))
                 return div + 1;
 
@@ -287,7 +294,8 @@ static int aclk_set_rate(struct clk *clk, unsigned long rate)
         u32 reg;
 
         reg = __raw_readl(clk->aclkreg) & ~ACLK_DIV_MASK;
-        reg |= aclk_best_div(clk, rate);
+        reg |= aclk_best_div(clk, rate) - 1;
+        __raw_writel(reg, clk->aclkreg);
         return 0;
 }