linux-kernel - Re: [PATCH v2 2/3] ARM: at91: pm: add per soc validation of pm modes

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Message-ID: <20200804114223.GC7836@piout.net>
Date:   Tue, 4 Aug 2020 13:42:23 +0200
From:   Alexandre Belloni <alexandre.belloni@...tlin.com>
To:     Claudiu Beznea <claudiu.beznea@...rochip.com>
Cc:     nicolas.ferre@...rochip.com, ludovic.desroches@...rochip.com,
        wenyou.yang@...el.com, linux-arm-kernel@...ts.infradead.org,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH v2 2/3] ARM: at91: pm: add per soc validation of pm modes

Hello,

On 04/08/2020 14:07:37+0300, Claudiu Beznea wrote:
>  void __init at91rm9200_pm_init(void)
>  {
> +	static const int modes[] __initconst = {

You don't need that to be static as it is now local to the function.

> +		AT91_PM_STANDBY, AT91_PM_ULP0
> +	};
> +
>  	if (!IS_ENABLED(CONFIG_SOC_AT91RM9200))
>  		return;
>  
> +	at91_pm_modes_validate(modes, ARRAY_SIZE(modes));

For rm9200 and at91sam9, I would not allow changing the pm_modes and
simply enforce standby_mode = AT91_PM_STANDBY and suspend_mode =
AT91_PM_ULP0. I don't think you have any user that ever changed that
behaviour also that avoids increasing the boot time for those slow SoCs.

>  	at91_dt_ramc();
>  
>  	/*
> @@ -838,9 +888,14 @@ void __init at91rm9200_pm_init(void)
>  
>  void __init sam9x60_pm_init(void)
>  {
> +	static const int modes[] __initconst = {
> +		AT91_PM_STANDBY, AT91_PM_ULP0, AT91_PM_ULP0_FAST, AT91_PM_ULP1,
> +	};
> +
>  	if (!IS_ENABLED(CONFIG_SOC_SAM9X60))
>  		return;
>  
> +	at91_pm_modes_validate(modes, ARRAY_SIZE(modes));
>  	at91_pm_modes_init();
>  	at91_dt_ramc();
>  	at91_pm_init(at91sam9x60_idle);
> @@ -851,14 +906,19 @@ void __init sam9x60_pm_init(void)
>  
>  void __init at91sam9_pm_init(void)
>  {
> +	static const int modes[] __initconst = {
> +		AT91_PM_STANDBY, AT91_PM_ULP0,
> +	};
> +
>  	if (!IS_ENABLED(CONFIG_SOC_AT91SAM9))
>  		return;
>  
> +	at91_pm_modes_validate(modes, ARRAY_SIZE(modes));
>  	at91_dt_ramc();
>  	at91_pm_init(at91sam9_idle);
>  }
>  
> -void __init sama5_pm_init(void)
> +static void __init sama5_pm(void)
>  {
>  	if (!IS_ENABLED(CONFIG_SOC_SAMA5))
>  		return;
> @@ -867,13 +927,32 @@ void __init sama5_pm_init(void)
>  	at91_pm_init(NULL);
>  }
>  
> +void __init sama5_pm_init(void)
> +{
> +	static const int modes[] __initconst = {
> +		AT91_PM_STANDBY, AT91_PM_ULP0, AT91_PM_ULP0_FAST,
> +	};
> +
> +	if (!IS_ENABLED(CONFIG_SOC_SAMA5))
> +		return;
> +
> +	at91_pm_modes_validate(modes, ARRAY_SIZE(modes));
> +	sama5_pm();
> +}
> +
>  void __init sama5d2_pm_init(void)
>  {
> +	static const int modes[] __initconst = {
> +		AT91_PM_STANDBY, AT91_PM_ULP0, AT91_PM_ULP0_FAST, AT91_PM_ULP1,
> +		AT91_PM_BACKUP,
> +	};
> +
>  	if (!IS_ENABLED(CONFIG_SOC_SAMA5D2))
>  		return;
>  
> +	at91_pm_modes_validate(modes, ARRAY_SIZE(modes));
>  	at91_pm_modes_init();
> -	sama5_pm_init();
> +	sama5_pm();

I would call those two directly:
	at91_dt_ramc();
	at91_pm_init(NULL);

instead of having a function that doesn't do much.

-- 
Alexandre Belloni, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com