[U-Boot] [PATCH 2/6] ARM: at91: clock: correct PRES offset for at91sam9x5

Andreas Bießmann andreas at biessmann.org
Thu Oct 6 23:40:53 CEST 2016


On 17.08.16 09:13, Heiko Schocher wrote:
> on at91sam9x5 PRES offset is 4 in the PMC master
> clock register.
> 
> Signed-off-by: Heiko Schocher <hs at denx.de>
> ---
> 
>  arch/arm/mach-at91/arm926ejs/clock.c | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/arch/arm/mach-at91/arm926ejs/clock.c b/arch/arm/mach-at91/arm926ejs/clock.c
> index c8d24ae..e3181fa 100644
> --- a/arch/arm/mach-at91/arm926ejs/clock.c
> +++ b/arch/arm/mach-at91/arm926ejs/clock.c
> @@ -162,7 +162,13 @@ int at91_clock_init(unsigned long main_clock)
>  	gd->arch.mck_rate_hz = at91_css_to_rate(mckr & AT91_PMC_MCKR_CSS_MASK);
>  	freq = gd->arch.mck_rate_hz;
>  
> +#if defined(CONFIG_AT91SAM9X5)
> +	/* different in prescale on at91sam9x5 */
> +	freq /= (1 << ((mckr & AT91_PMC_MCKR_PRES_MASK) >> 4));

This one is really ugly ... I can live with the ifdef here but have you
realized the 0x7 for PRES?

Andreas

> +#else
>  	freq /= (1 << ((mckr & AT91_PMC_MCKR_PRES_MASK) >> 2));	/* prescale */
> +#endif
> +
>  #if defined(CONFIG_AT91SAM9G20)
>  	/* mdiv ; (x >> 7) = ((x >> 8) * 2) */
>  	gd->arch.mck_rate_hz = (mckr & AT91_PMC_MCKR_MDIV_MASK) ?
> 


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