[U-Boot] [PATCH] Exynos5: clock: Update the equation to calculate PLL output frequency

Minkyu Kang mk7.kang at samsung.com
Tue May 21 13:19:09 CEST 2013


Dear Akshay Saraswat,

On 22/03/13 21:26, Akshay Saraswat wrote:
> According to the latest exynos5 user manual, the equation for
> calculating PLL output was changed to
> FOUT= MDIV x FIN/(PDIV x 2^SDIV)
> earlier it was
> FOUT= MDIV x FIN/(PDIV x 2^(SDIV -1))
> So updating the clock code accordingly.
> 
> Signed-off-by: Hatim Ali <hatim.rv at samsung.com>
> Signed-off-by: Akshay Saraswat <akshay.s at samsung.com>
> ---
>  arch/arm/cpu/armv7/exynos/clock.c | 6 ++----
>  1 file changed, 2 insertions(+), 4 deletions(-)
> 
> diff --git a/arch/arm/cpu/armv7/exynos/clock.c b/arch/arm/cpu/armv7/exynos/clock.c
> index 956427c..5299bc7 100644
> --- a/arch/arm/cpu/armv7/exynos/clock.c
> +++ b/arch/arm/cpu/armv7/exynos/clock.c
> @@ -73,10 +73,8 @@ static int exynos_get_pll_clk(int pllreg, unsigned int r, unsigned int k)
>  		/* FOUT = (MDIV + K / 1024) * FIN / (PDIV * 2^SDIV) */
>  		fout = (m + k / 1024) * (freq / (p * (1 << s)));
>  	} else {
> -		if (s < 1)
> -			s = 1;
> -		/* FOUT = MDIV * FIN / (PDIV * 2^(SDIV - 1)) */
> -		fout = m * (freq / (p * (1 << (s - 1))));
> +		/* FOUT = MDIV * FIN / (PDIV * 2^SDIV) */
> +		fout = m * (freq / (p * (1 << s)));
>  	}
>  
>  	return fout;
> 

applied to u-boot-samsung.

Thanks,
Minkyu Kang.


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