[U-Boot] [PATCH V2] arm: omap3: Enable clocks for peripherals only if they are used

Igor Grinberg grinberg at compulab.co.il
Sun Dec 1 12:21:12 CET 2013


On 11/30/13 08:59, Michael Trimarchi wrote:
> This patch change the per_clocks_enable() function used in OMAP3
> code to enable peripherals clocks. Only required clock should be
> activated. So if the board use the uart(x) as a console we need
> to activate it. The Board's config should include define to enable
> every subsystem that the board use. For a complete list
> of affected peripherals, registers CM_FCLKEN_PER and CM_ICLKEN_PER
> should be checked.
> Right now the bootloader can enable and disable clocks for:
> uart(x) using CONFIG_SYS_NS16550
> gpio bank (x) using CONFIG_OMAP3_GPIO_X with X = { 2, 3, 4, 5, 6 }
> i2c bus using CONFIG_DRIVER_OMAP34XX_I2C.
> 
> Not required gptimer(x) and mcbsp(x) for booting are disabled by default and
> are not supported by any define.
> Their activation need to included in the per_clocks_enable if the
> peripheral is included. Not booting board should enable the peripheral
> clock connected to their driver
> 
> Signed-off-by: Michael Trimarchi <michael at amarulasolutions.com>
> Cc: Igor Grinberg <grinberg at compulab.co.il>
> Cc: Tom Rini <trini at ti.com>

Thanks!

Acked-by: Igor Grinberg <grinberg at compulab.co.il>

> ---
> Changes in V2:
> 	add a better comment for describe the problems that could
> 	be raised on some boards
> 
>  arch/arm/cpu/armv7/omap3/clock.c        | 2 --
>  arch/arm/include/asm/arch-omap3/clock.h | 2 --
>  2 files changed, 4 deletions(-)
> 
> diff --git a/arch/arm/cpu/armv7/omap3/clock.c b/arch/arm/cpu/armv7/omap3/clock.c
> index 14fc7e8..1bc27bd 100644
> --- a/arch/arm/cpu/armv7/omap3/clock.c
> +++ b/arch/arm/cpu/armv7/omap3/clock.c
> @@ -730,8 +730,6 @@ void per_clocks_enable(void)
>  		sr32(&prcm_base->fclken_cam, 0, 32, FCK_CAM_ON);
>  		sr32(&prcm_base->iclken_cam, 0, 32, ICK_CAM_ON);
>  	}
> -	sr32(&prcm_base->fclken_per, 0, 32, FCK_PER_ON);
> -	sr32(&prcm_base->iclken_per, 0, 32, ICK_PER_ON);
>  
>  	sdelay(1000);
>  }
> diff --git a/arch/arm/include/asm/arch-omap3/clock.h b/arch/arm/include/asm/arch-omap3/clock.h
> index be669c1..1912cc9 100644
> --- a/arch/arm/include/asm/arch-omap3/clock.h
> +++ b/arch/arm/include/asm/arch-omap3/clock.h
> @@ -27,8 +27,6 @@
>  #define ICK_DSS_ON	0x00000001
>  #define FCK_CAM_ON	0x00000001
>  #define ICK_CAM_ON	0x00000001
> -#define FCK_PER_ON	0x0003ffff
> -#define ICK_PER_ON	0x0003ffff
>  
>  /* Used to index into DPLL parameter tables */
>  typedef struct {
> 

-- 
Regards,
Igor.


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