ARM: imx: pllv1: Fix PLL calculation for i.MX27

MFN bit 9 on i.MX27 has a different meaning than in other SOCs. This
is a just sign bit. This patch makes different calculation for i.MX27.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>

diff --git a/arch/arm/mach-imx/clk-pllv1.c b/arch/arm/mach-imx/clk-pllv1.c
index c1eaee3469542d08660d0a4aecc81a1f468f5041..d21d14ca46c1786b4cc42f47976cbdc6cc384d5d 100644 (file)
--- a/arch/arm/mach-imx/clk-pllv1.c
+++ b/arch/arm/mach-imx/clk-pllv1.c
@@ -18,6 +18,11 @@
  *
  * PLL clock version 1, found on i.MX1/21/25/27/31/35
  */
+
+#define MFN_BITS       (10)
+#define MFN_SIGN       (BIT(MFN_BITS - 1))
+#define MFN_MASK       (MFN_SIGN - 1)
+
 struct clk_pllv1 {
        struct clk_hw   hw;
        void __iomem    *base;
@@ -25,6 +30,11 @@ struct clk_pllv1 {
 
 #define to_clk_pllv1(clk) (container_of(clk, struct clk_pllv1, clk))
 
+static inline bool mfn_is_negative(unsigned int mfn)
+{
+       return !cpu_is_mx1() && !cpu_is_mx21() && (mfn & MFN_SIGN);
+}
+
 static unsigned long clk_pllv1_recalc_rate(struct clk_hw *hw,
                unsigned long parent_rate)
 {
@@ -58,10 +68,15 @@ static unsigned long clk_pllv1_recalc_rate(struct clk_hw *hw,
 
        /*
         * On all i.MXs except i.MX1 and i.MX21 mfn is a 10bit
-        * 2's complements number
+        * 2's complements number.
+        * On i.MX27 the bit 9 is the sign bit.
         */
-       if (!cpu_is_mx1() && !cpu_is_mx21() && mfn >= 0x200)
-               mfn_abs = 0x400 - mfn;
+       if (mfn_is_negative(mfn)) {
+               if (cpu_is_mx27())
+                       mfn_abs = mfn & MFN_MASK;
+               else
+                       mfn_abs = BIT(MFN_BITS) - mfn;
+       }
 
        rate = parent_rate * 2;
        rate /= pd + 1;
@@ -70,7 +85,7 @@ static unsigned long clk_pllv1_recalc_rate(struct clk_hw *hw,
 
        do_div(ll, mfd + 1);
 
-       if (!cpu_is_mx1() && !cpu_is_mx21() && mfn >= 0x200)
+       if (mfn_is_negative(mfn))
                ll = -ll;
 
        ll = (rate * mfi) + ll;