Exynos: Fix ARM Clock frequency calculation

Earliar ARM clock frequency was calculated by:
MOUTAPLL/(DIVAPLL + 1) which is actually returning SCLKAPLL.
It is fixed by calculating it as follows:
ARMCLK=MOUTCORE / (DIVCORE + 1) / (DIVCORE2 + 1)

Signed-off-by: Chander Kashyap <chander.kashyap@linaro.org>
Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>

diff --git a/arch/arm/cpu/armv7/exynos/clock.c b/arch/arm/cpu/armv7/exynos/clock.c
index 64de262..0c199cd 100644 (file)
--- a/arch/arm/cpu/armv7/exynos/clock.c
+++ b/arch/arm/cpu/armv7/exynos/clock.c
@@ -102,17 +102,20 @@ static unsigned long exynos4_get_arm_clk(void)
        struct exynos4_clock *clk =
                (struct exynos4_clock *)samsung_get_base_clock();
        unsigned long div;
-       unsigned long dout_apll;
-       unsigned int apll_ratio;
+       unsigned long armclk;
+       unsigned int core_ratio;
+       unsigned int core2_ratio;
 
        div = readl(&clk->div_cpu0);
 
-       /* APLL_RATIO: [26:24] */
-       apll_ratio = (div >> 24) & 0x7;
+       /* CORE_RATIO: [2:0], CORE2_RATIO: [30:28] */
+       core_ratio = (div >> 0) & 0x7;
+       core2_ratio = (div >> 28) & 0x7;
 
-       dout_apll = get_pll_clk(APLL) / (apll_ratio + 1);
+       armclk = get_pll_clk(APLL) / (core_ratio + 1);
+       armclk /= (core2_ratio + 1);
 
-       return dout_apll;
+       return armclk;
 }
 
 /* exynos4: return pwm clock frequency */