[PATCH] ARM: i.MX8MP-EVK: increase VDD_ARM to OD voltage

Sascha Hauer sha at pengutronix.de
Tue Feb 7 23:55:50 PST 2023


On Mon, Feb 06, 2023 at 09:59:28PM +0100, Lucas Stach wrote:
> The Linux kernel or whatever is started from Barebox might switch the
> ARM frequency to OD level, without first reprogramming the PMIC as
> required. This might lead to system instability. To avoid this,
> increase VDD_ARM to OD level. When the kernel handles the PMIC properly
> it will drop the voltage back to ND level when appropriate.
> 
> Signed-off-by: Lucas Stach <l.stach at pengutronix.de>
> ---
>  arch/arm/boards/nxp-imx8mp-evk/lowlevel.c | 6 ++++++
>  1 file changed, 6 insertions(+)

Applied, thanks

Sascha

> 
> diff --git a/arch/arm/boards/nxp-imx8mp-evk/lowlevel.c b/arch/arm/boards/nxp-imx8mp-evk/lowlevel.c
> index 3cb24df1ca3f..d6fc32e65b61 100644
> --- a/arch/arm/boards/nxp-imx8mp-evk/lowlevel.c
> +++ b/arch/arm/boards/nxp-imx8mp-evk/lowlevel.c
> @@ -61,6 +61,12 @@ static struct pmic_config pca9450_cfg[] = {
>  	{ PCA9450_BUCK1OUT_DVS0, 0x1C },
>  	{ PCA9450_BUCK1OUT_DVS1, 0x14 },
>  	{ PCA9450_BUCK1CTRL, 0x59 },
> +	/*
> +	 * Increase VDD_ARM to 0.95V to avoid issues in case software after
> +	 * Barebox switches to the OD ARM frequency without reprogramming the
> +	 * PMIC first.
> +	 */
> +	{ PCA9450_BUCK2OUT_DVS0, 0x1C },
>  	/* set WDOG_B_CFG to cold reset */
>  	{ PCA9450_RESET_CTRL, 0xA1 },
>  };
> -- 
> 2.39.1
> 
> 
> 

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