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

From: Nicolas Ferre
Date: Tue Mar 03 2015 - 13:42:29 EST


Le 05/02/2015 07:01, Wenyou Yang a écrit :
> From: Sylvain Rochet <sylvain.rochet@xxxxxxxxxxxx>
>
> 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 <sylvain.rochet@xxxxxxxxxxxx>
> Acked-by: Wenyou.Yang <wenyou.yang@xxxxxxxxx>

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
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