MXC PLL decoding: calculate mfn value with less magic

Also, use cpu_is_* macros rather than CONFIG_ARCH_*

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

1 files changed, 9 insertions, 7 deletions

diff --git a/arch/arm/plat-mxc/clock.c b/arch/arm/plat-mxc/clock.c
index 92e13566cd4f..f653213b7416 100644
--- a/arch/arm/plat-mxc/clock.c
+++ b/arch/arm/plat-mxc/clock.c
@@ -39,6 +39,7 @@
 #include <linux/string.h>
 
 #include <mach/clock.h>
+#include <mach/hardware.h>
 
 static LIST_HEAD(clocks);
 static DEFINE_MUTEX(clocks_mutex);
@@ -363,12 +364,11 @@ unsigned long mxc_decode_pll(unsigned int reg_val, u32 freq)
 
         mfn_abs = mfn;
 
-#if !defined CONFIG_ARCH_MX1 && !defined CONFIG_ARCH_MX21
-        if (mfn >= 0x200) {
-                mfn |= 0xFFFFFE00;
-                mfn_abs = -mfn;
-        }
-#endif
+        /* On all i.MXs except i.MX1 and i.MX21 mfn is a 10bit
+         * 2's complements number
+         */
+        if (!cpu_is_mx1() && !cpu_is_mx21() && mfn >= 0x200)
+                mfn_abs = 0x400 - mfn;
 
         freq *= 2;
         freq /= pd + 1;
@@ -376,8 +376,10 @@ unsigned long mxc_decode_pll(unsigned int reg_val, u32 freq)
         ll = (unsigned long long)freq * mfn_abs;
 
         do_div(ll, mfd + 1);
-        if (mfn < 0)
+
+        if (!cpu_is_mx1() && !cpu_is_mx21() && mfn >= 0x200)
                 ll = -ll;
+
         ll = (freq * mfi) + ll;
 
         return ll;