[U-Boot] [PATCH 12/14] tegra: Set vdd_core and vdd_cpu to high

Stephen Warren swarren at nvidia.com
Tue Jan 10 19:40:32 CET 2012


On 12/26/2011 12:33 PM, Simon Glass wrote:
> From: Jimmy Zhang <jimmzhang at nvidia.com>
> 
> At cold boot, the default voltage supplied by pmu is not high enough
> to support emc to run at its highest clock frequency. The code added
> here is to update the default vdd_core and vdd_cpu to higher values.
> 
> (Sorry if I have mangled this comment)

?? Remove that last line?

I thought this issue only affected the T25 SKU when coupled with a
particular voltage regulator that wasn't reprogrammed to explicitly
support T25. Hence, shouldn't this code only be enabled for specific boards?

> diff --git a/board/nvidia/common/board.c b/board/nvidia/common/board.c
...
>  /*
> + * Routine: power_det_init
> + * Description: turn off power detects
> + */
> +static void power_det_init(void)
> +{
> +#if defined(CONFIG_TEGRA2)
> +	struct pmc_ctlr *const pmc = (struct pmc_ctlr *)TEGRA2_PMC_BASE;
> +
> +	/* turn off power detects */
> +	writel(0, &pmc->pmc_pwr_det_latch);
> +	writel(0, &pmc->pmc_pwr_det);
> +#endif
> +}

I can't tell how that code relates to the commit description.

-- 
nvpublic


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