[U-Boot] [PATCH 2/2] Exynos: Fix ARM Clock frequency calculation

[Minkyu Kang]

On 19 December 2011 16:57, Wolfgang Denk <wd at denx.de> wrote:
> Dear Chander Kashyap,
>
> In message <1324275424-29468-3-git-send-email-chander.kashyap at linaro.org> you wrote:
>> Earliar ARM clock frequency was calculated by:
>> MOUTAPLL/(DIVAPLL + 1) which is actually returning SCLKAPLL.
>> It is fixed by calcuating it as follows:
>
> Um.... Comment and code disagree:
>
>> ARMCLK=MOUTCORE/(DIVCORE + 1)/DIVCORE2 + 1)
>
> ...or is this just missing a paren?
>
>> +     dout_apll = get_pll_clk(APLL) / (core_ratio + 1);
>> +     dout_apll /= (core2_ratio + 1);
>
> This gives
>
>  ARMCLK=MOUTCORE/(DIVCORE + 1)/ (DIVCORE2 + 1)
>
> Please check if this is correct.

Wolfgang, you are right.
ARMCLK=MOUTCORE / (DIVCORE + 1) / (DIVCORE2 + 1) is right.


Dear Chander Kashyap,

>        /* APLL_RATIO: [26:24] */

Please fix this comment also.

> -       apll_ratio = (div >> 24) & 0x7;
> +       core_ratio = (div >> 0) & 0x7;
> +       core2_ratio = (div >> 28) & 0x7;
>
> -       dout_apll = get_pll_clk(APLL) / (apll_ratio + 1);
> +       dout_apll = get_pll_clk(APLL) / (core_ratio + 1);

This output is not dout_apll.
Please fix it.

> +       dout_apll /= (core2_ratio + 1);
>
>        return dout_apll;

Thanks
Minkyu Kang
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