[U-Boot] [PATCH] i.MX6: Add ANATOP regulator init

Dirk Behme dirk.behme at de.bosch.com
Wed Apr 18 12:41:18 CEST 2012


On 13.04.2012 10:00, Dirk Behme wrote:
> Init the core regulator voltage to 1.2V. This is required for the correct
> functioning of the GPU and when the ARM LDO is set to 1.225V. This is a
> workaround to fix some memory clock jitter.
> 
> Note: This should be but can't be done in the DCD. The bootloader
>       prevents access to the ANATOP registers.
> 
> Signed-off-by: Dirk Behme <dirk.behme at de.bosch.com>
> CC: Jason Chen <b02280 at freescale.com>
> CC: Jason Liu <r64343 at freescale.com>
> CC: Ranjani Vaidyanathan <ra5478 at freescale.com>
> CC: Stefano Babic <sbabic at denx.de>
> CC: Fabio Estevam <festevam at gmail.com>
> ---
>  arch/arm/cpu/armv7/mx6/soc.c |   16 ++++++++++++++++
>  1 files changed, 16 insertions(+), 0 deletions(-)
> 
> diff --git a/arch/arm/cpu/armv7/mx6/soc.c b/arch/arm/cpu/armv7/mx6/soc.c
> index 543b2cc..957ea34 100644
> --- a/arch/arm/cpu/armv7/mx6/soc.c
> +++ b/arch/arm/cpu/armv7/mx6/soc.c
> @@ -77,10 +77,26 @@ void init_aips(void)
>  	writel(0x00000000, &aips2->opacr4);
>  }
>  
> +static void init_anatop_reg(void)
> +{
> +	struct anatop_regs *anatop = (struct anatop_regs *)ANATOP_BASE_ADDR;
> +	int reg = readl(&anatop->reg_core);
> +
> +	/*
> +	 * Increase the VDDSOC to 1.2V
> +	 * Mask out the REG_CORE[22:18] bits (REG2_TRIG)
> +	 * and set them to 1.2V (0.7V + 0x14 * 0.025V)
> +	 */
> +	reg = (reg & ~(0x1F << 18)) | (0x14 << 18);
> +	writel(reg, &anatop->reg_core);
> +}
> +
>  int arch_cpu_init(void)
>  {
>  	init_aips();
>  
> +	init_anatop_reg();
> +
>  	return 0;
>  }
>  #endif

Any comments on this?

Many thanks

Dirk


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