diff options
Diffstat (limited to 'arch/arm/mach-imx/clk-pllv1.c')
| -rw-r--r-- | arch/arm/mach-imx/clk-pllv1.c | 49 |
1 files changed, 47 insertions, 2 deletions
diff --git a/arch/arm/mach-imx/clk-pllv1.c b/arch/arm/mach-imx/clk-pllv1.c index 2d856f9ccf59..02be73178912 100644 --- a/arch/arm/mach-imx/clk-pllv1.c +++ b/arch/arm/mach-imx/clk-pllv1.c @@ -6,7 +6,7 @@ #include <linux/err.h> #include <mach/common.h> #include <mach/hardware.h> -#include <mach/clock.h> + #include "clk.h" /** @@ -29,8 +29,53 @@ static unsigned long clk_pllv1_recalc_rate(struct clk_hw *hw, unsigned long parent_rate) { struct clk_pllv1 *pll = to_clk_pllv1(hw); + long long ll; + int mfn_abs; + unsigned int mfi, mfn, mfd, pd; + u32 reg; + unsigned long rate; + + reg = readl(pll->base); + + /* + * Get the resulting clock rate from a PLL register value and the input + * frequency. PLLs with this register layout can be found on i.MX1, + * i.MX21, i.MX27 and i,MX31 + * + * mfi + mfn / (mfd + 1) + * f = 2 * f_ref * -------------------- + * pd + 1 + */ + + mfi = (reg >> 10) & 0xf; + mfn = reg & 0x3ff; + mfd = (reg >> 16) & 0x3ff; + pd = (reg >> 26) & 0xf; + + mfi = mfi <= 5 ? 5 : mfi; + + mfn_abs = mfn; + + /* + * 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; + + rate = parent_rate * 2; + rate /= pd + 1; + + ll = (unsigned long long)rate * mfn_abs; + + do_div(ll, mfd + 1); + + if (!cpu_is_mx1() && !cpu_is_mx21() && mfn >= 0x200) + ll = -ll; + + ll = (rate * mfi) + ll; - return mxc_decode_pll(readl(pll->base), parent_rate); + return ll; } struct clk_ops clk_pllv1_ops = { |