Subject: [PATCH 2/3] pm: at91: pm_slowclock: remove clocks which are already stopped when entering slow clock mode

From: [email-masked] (Nicolas Ferre)
Date: Tue, 3 Mar 2015 19:42:26 +0100

Le 05/02/2015 07:01, Wenyou Yang a ?crit :
> From: Sylvain Rochet <[email-masked]>
> 
> Assume USB PLL and PLL B are already stopped before entering sleep mode,
> print a warning if this isn't the case.
> 
> Removed PLL B from slow clock code, all drivers are supposed to properly
> unprepare clocks.
> 
> Signed-off-by: Sylvain Rochet <[email-masked]>
> Acked-by: Wenyou.Yang <[email-masked]>

I keep this one for 4.1 as all the USB drivers are not converted yet.

Bye,

> ---
>  arch/arm/mach-at91/pm.c           |   12 ++++++++++++
>  arch/arm/mach-at91/pm_slowclock.S |   31 -------------------------------
>  2 files changed, 12 insertions(+), 31 deletions(-)
> 
> diff --git a/arch/arm/mach-at91/pm.c b/arch/arm/mach-at91/pm.c
> index 9b15169..1cfd6e9 100644
> --- a/arch/arm/mach-at91/pm.c
> +++ b/arch/arm/mach-at91/pm.c
> @@ -98,6 +98,18 @@ static int at91_pm_verify_clocks(void)
>  		}
>  	}
>  
> +	/* Drivers should have previously suspended USB PLL */
> +	if (at91_pmc_read(AT91_CKGR_UCKR) & AT91_PMC_UPLLEN) {
> +		pr_err("AT91: PM - Suspend-to-RAM with USB PLL running\n");
> +		return 0;
> +	}
> +
> +	/* Drivers should have previously suspended PLL B */
> +	if (at91_pmc_read(AT91_PMC_SR) & AT91_PMC_LOCKB) {
> +		pr_err("AT91: PM - Suspend-to-RAM with PLL B running\n");
> +		return 0;
> +	}
> +
>  	return 1;
>  }
>  
> diff --git a/arch/arm/mach-at91/pm_slowclock.S b/arch/arm/mach-at91/pm_slowclock.S
> index 79dfdbe..75d8b19 100644
> --- a/arch/arm/mach-at91/pm_slowclock.S
> +++ b/arch/arm/mach-at91/pm_slowclock.S
> @@ -68,15 +68,6 @@ tmp2	.req	r5
>  	beq	1b
>  	.endm
>  
> -/*
> - * Wait until PLLB has locked.
> - */
> -	.macro wait_pllblock
> -1:	ldr	tmp1, [pmc, #AT91_PMC_SR]
> -	tst	tmp1, #AT91_PMC_LOCKB
> -	beq	1b
> -	.endm
> -
>  	.text
>  
>  /* void at91_slow_clock(void __iomem *pmc, void __iomem *sdramc,
> @@ -182,13 +173,6 @@ sdr_sr_done:
>  	orr	tmp1, tmp1, #(1 << 29)		/* bit 29 always set */
>  	str	tmp1, [pmc, #AT91_CKGR_PLLAR]
>  
> -	/* Save PLLB setting and disable it */
> -	ldr	tmp1, [pmc, #AT91_CKGR_PLLBR]
> -	str	tmp1, .saved_pllbr
> -
> -	mov	tmp1, #AT91_PMC_PLLCOUNT
> -	str	tmp1, [pmc, #AT91_CKGR_PLLBR]
> -
>  	/* Turn off the main oscillator */
>  	ldr	tmp1, [pmc, #AT91_CKGR_MOR]
>  	bic	tmp1, tmp1, #AT91_PMC_MOSCEN
> @@ -204,18 +188,6 @@ sdr_sr_done:
>  
>  	wait_moscrdy
>  
> -	/* Restore PLLB setting */
> -	ldr	tmp1, .saved_pllbr
> -	str	tmp1, [pmc, #AT91_CKGR_PLLBR]
> -
> -	tst	tmp1, #(AT91_PMC_MUL &  0xff0000)
> -	bne	1f
> -	tst	tmp1, #(AT91_PMC_MUL & ~0xff0000)
> -	beq	2f
> -1:
> -	wait_pllblock
> -2:
> -
>  	/* Restore PLLA setting */
>  	ldr	tmp1, .saved_pllar
>  	str	tmp1, [pmc, #AT91_CKGR_PLLAR]
> @@ -294,9 +266,6 @@ ram_restored:
>  .saved_pllar:
>  	.word 0
>  
> -.saved_pllbr:
> -	.word 0
> -
>  .saved_sam9_lpr:
>  	.word 0
>  
> 

-- 
Nicolas Ferre