Re: [PATCH] ARM: imx: pllv1: Fix PLL calculation for i.MX27
Alexander Shiyan
shc_work at mail.ru
Sat Jul 27 08:35:39 EDT 2013
Incorrect. Please forget about this patch.
> 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 at mail.ru>
> ---
> arch/arm/mach-imx/clk-pllv1.c | 16 +++++++++++++---
> 1 file changed, 13 insertions(+), 3 deletions(-)
>
> diff --git a/arch/arm/mach-imx/clk-pllv1.c b/arch/arm/mach-imx/clk-pllv1.c
> index c1eaee3..e76d601 100644
> --- a/arch/arm/mach-imx/clk-pllv1.c
> +++ b/arch/arm/mach-imx/clk-pllv1.c
> @@ -25,6 +25,11 @@ struct clk_pllv1 {
>
> #define to_clk_pllv1(clk) (container_of(clk, struct clk_pllv1, clk))
>
> +static inline bool allow_signed_mfn(void)
> +{
> + return !cpu_is_mx1() && !cpu_is_mx21();
> +}
> +
> static unsigned long clk_pllv1_recalc_rate(struct clk_hw *hw,
> unsigned long parent_rate)
> {
> @@ -59,9 +64,14 @@ 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
> + * On i.MX27 the bit 9 is the sign bit.
> */
> - if (!cpu_is_mx1() && !cpu_is_mx21() && mfn >= 0x200)
> - mfn_abs = 0x400 - mfn;
> + if (allow_signed_mfn() && (mfn & 0x200)) {
> + if (cpu_is_mx27())
> + mfn_abs = mfn & 0x200;
> + else
> + mfn_abs = 0x400 - mfn;
> + }
>
> rate = parent_rate * 2;
> rate /= pd + 1;
> @@ -70,7 +80,7 @@ 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 (allow_signed_mfn() && (mfn & 0x200))
> ll = -ll;
>
> ll = (rate * mfi) + ll;
> --
---
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