[U-Boot] [PATCH 7/9 V2] EXYNOS5: CLOCK: Modify MPLL clock out for Exynos5250 Rev 1.0

Minkyu Kang promsoft at gmail.com
Tue Jun 26 09:02:46 CEST 2012


Dear Rajeshwari Shinde,

On 20 June 2012 20:11, Rajeshwari Shinde <rajeshwari.s at samsung.com> wrote:
> MPLL clock-out of Exynos5250 Rev 1.0 is always at 1.6GHz.
> Adjust the divisor value to get 800MHz as needed by devices
> like UART etc
>
> Signed-off-by: Hatim Ali <hatim.rv at samsung.com>
> Signed-off-by: Rajeshwari Shinde <rajeshwari.s at samsung.com>
> ---
> Chnages in V2:
>        - None
>  arch/arm/cpu/armv7/exynos/clock.c        |   12 +++++++++++-
>  arch/arm/include/asm/arch-exynos/clock.h |    3 +++
>  2 files changed, 14 insertions(+), 1 deletions(-)
>
> diff --git a/arch/arm/cpu/armv7/exynos/clock.c b/arch/arm/cpu/armv7/exynos/clock.c
> index 330bd75..dbd5f11 100644
> --- a/arch/arm/cpu/armv7/exynos/clock.c
> +++ b/arch/arm/cpu/armv7/exynos/clock.c
> @@ -98,7 +98,7 @@ static unsigned long exynos5_get_pll_clk(int pllreg)
>        struct exynos5_clock *clk =
>                (struct exynos5_clock *)samsung_get_base_clock();
>        unsigned long r, m, p, s, k = 0, mask, fout;
> -       unsigned int freq;
> +       unsigned int freq, pll_div2_sel,  mpll_fout_sel;
>
>        switch (pllreg) {
>        case APLL:
> @@ -155,6 +155,16 @@ static unsigned long exynos5_get_pll_clk(int pllreg)
>                fout = m * (freq / (p * (1 << (s - 1))));
>        }
>
> +       /* According to the user manual, in EVT1 MPLL always gives
> +        * 1.6GHz clock, so divide by 2 to get 800MHz MPLL clock.*/

Please fix multiline comment style.

> +       if (pllreg == MPLL) {
> +               pll_div2_sel = readl(&clk->pll_div2_sel);
> +               mpll_fout_sel = (pll_div2_sel >> MPLL_FOUT_SEL_SHIFT)
> +                               & MPLL_FOUT_SEL_MASK;
> +               if (mpll_fout_sel == 0)
> +                       fout /= 2;
> +       }
> +
>        return fout;
>  }
>

Thanks.
Minkyu Kang.
-- 
from. prom.
www.promsoft.net


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