[PATCH v2 2/2] mx7ulp: Only enable LDO if it is not already enabled

[Peng Fan]

> Subject: [PATCH v2 2/2] mx7ulp: Only enable LDO if it is not already enabled
> 
> LDO mode may be already enabled by the ROM and enabling it again can
> cause U-Boot to hang.
> 
> Avoid this problem by only enabling LDO mode if it is initially disabled.
> 
> Reported-by: Jorge Ramirez-Ortiz <jorge at foundries.io>
> Signed-off-by: Fabio Estevam <festevam at gmail.com>
> Tested-by: Jorge Ramirez-Ortiz <jorge at foundries.io>

Reviewed-by: Peng Fan <peng.fan at nxp.com>


Just have a question, LDO mode enabled by ROM, this is configured with fuse?

Is there any special configuration need to be done in Linux? I not touch this
part before (:

Thanks,
Peng.

> ---
> Changes since v1:
> - Drop the define changes as they are duplicated (Stefano).
> 
>  arch/arm/mach-imx/mx7ulp/soc.c | 25 ++++++++++++++-----------
>  1 file changed, 14 insertions(+), 11 deletions(-)
> 
> diff --git a/arch/arm/mach-imx/mx7ulp/soc.c
> b/arch/arm/mach-imx/mx7ulp/soc.c index d8d691692c..0d39dab7ea 100644
> --- a/arch/arm/mach-imx/mx7ulp/soc.c
> +++ b/arch/arm/mach-imx/mx7ulp/soc.c
> @@ -118,12 +118,26 @@ void init_wdog(void)
>  	disable_wdog(WDG2_RBASE);
>  }
> 
> +static bool ldo_mode_is_enabled(void)
> +{
> +	unsigned int reg;
> +
> +	reg = readl(PMC0_BASE_ADDR + PMC0_CTRL);
> +	if (reg & PMC0_CTRL_LDOEN)
> +		return true;
> +	else
> +		return false;
> +}
> +
>  #if !defined(CONFIG_SPL) || (defined(CONFIG_SPL) &&
> defined(CONFIG_SPL_BUILD))  #if defined(CONFIG_LDO_ENABLED_MODE)
> static void init_ldo_mode(void)  {
>  	unsigned int reg;
> 
> +	if (ldo_mode_is_enabled())
> +		return;
> +
>  	/* Set LDOOKDIS */
>  	setbits_le32(PMC0_BASE_ADDR + PMC0_CTRL,
> PMC0_CTRL_LDOOKDIS);
> 
> @@ -193,17 +207,6 @@ const char *get_imx_type(u32 imxtype)
>  	return "7ULP";
>  }
> 
> -static bool ldo_mode_is_enabled(void)
> -{
> -	unsigned int reg;
> -
> -	reg = readl(PMC0_BASE_ADDR + PMC0_CTRL);
> -	if (reg & PMC0_CTRL_LDOEN)
> -		return true;
> -	else
> -		return false;
> -}
> -
>  int print_cpuinfo(void)
>  {
>  	u32 cpurev;
> --
> 2.17.1