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Re: [PATCH v2 1/9] clk: at91: pmc: Wait for clocks when resuming

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On Fri, Sep 15, 2017 at 04:04:03PM +0200, Romain Izard wrote:
> Wait for the syncronization of all clocks when resuming, not only the
> UPLL clock. Do not use regmap_read_poll_timeout, as it will call BUG()
> when interrupts are masked, which is the case in here.
> 
> Signed-off-by: Romain Izard <romain.izard.pro@gmail.com>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>

I faced the same issue because of the use of regmap_read_poll_timeout
when timekeeping is not ready.


Ludovic

> ---
>  drivers/clk/at91/pmc.c | 24 ++++++++++++++++--------
>  1 file changed, 16 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/clk/at91/pmc.c b/drivers/clk/at91/pmc.c
> index 775af473fe11..5c2b26de303e 100644
> --- a/drivers/clk/at91/pmc.c
> +++ b/drivers/clk/at91/pmc.c
> @@ -107,10 +107,20 @@ static int pmc_suspend(void)
>  	return 0;
>  }
>  
> +static bool pmc_ready(unsigned int mask)
> +{
> +	unsigned int status;
> +
> +	regmap_read(pmcreg, AT91_PMC_SR, &status);
> +
> +	return ((status & mask) == mask) ? 1 : 0;
> +}
> +
>  static void pmc_resume(void)
>  {
> -	int i, ret = 0;
> +	int i;
>  	u32 tmp;
> +	u32 mask = AT91_PMC_MCKRDY | AT91_PMC_LOCKA;
>  
>  	regmap_read(pmcreg, AT91_PMC_MCKR, &tmp);
>  	if (pmc_cache.mckr != tmp)
> @@ -134,13 +144,11 @@ static void pmc_resume(void)
>  			     AT91_PMC_PCR_CMD);
>  	}
>  
> -	if (pmc_cache.uckr & AT91_PMC_UPLLEN) {
> -		ret = regmap_read_poll_timeout(pmcreg, AT91_PMC_SR, tmp,
> -					       !(tmp & AT91_PMC_LOCKU),
> -					       10, 5000);
> -		if (ret)
> -			pr_crit("USB PLL didn't lock when resuming\n");
> -	}
> +	if (pmc_cache.uckr & AT91_PMC_UPLLEN)
> +		mask |= AT91_PMC_LOCKU;
> +
> +	while (!pmc_ready(mask))
> +		cpu_relax();
>  }
>  
>  static struct syscore_ops pmc_syscore_ops = {
> -- 
> 2.11.0
> 

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[PATCH v2 0/9] Various patches for SAMA5D2 backup mode Romain Izard <romain.izard.pro@gmail.com> - 2017-09-15 16:10 +0200
  [PATCH v2 9/9] tty/serial: atmel: Prevent a warning on suspend Romain Izard <romain.izard.pro@gmail.com> - 2017-09-15 16:10 +0200
    Re: [PATCH v2 9/9] tty/serial: atmel: Prevent a warning on suspend Nicolas Ferre <nicolas.ferre@microchip.com> - 2017-09-19 12:20 +0200
    Re: [PATCH v2 9/9] tty/serial: atmel: Prevent a warning on suspend Richard Genoud <richard.genoud@gmail.com> - 2017-09-20 16:40 +0200
  [PATCH v2 6/9] ehci-atmel: Power down during suspend is normal Romain Izard <romain.izard.pro@gmail.com> - 2017-09-15 16:10 +0200
    Re: [PATCH v2 6/9] ehci-atmel: Power down during suspend is normal Nicolas Ferre <nicolas.ferre@microchip.com> - 2017-09-22 14:40 +0200
  [PATCH v2 7/9] pwm: atmel-tcb: Support backup mode Romain Izard <romain.izard.pro@gmail.com> - 2017-09-15 16:10 +0200
    Re: [PATCH v2 7/9] pwm: atmel-tcb: Support backup mode Nicolas Ferre <nicolas.ferre@microchip.com> - 2017-09-22 14:50 +0200
  [PATCH v2 1/9] clk: at91: pmc: Wait for clocks when resuming Romain Izard <romain.izard.pro@gmail.com> - 2017-09-15 16:10 +0200
    Re: [PATCH v2 1/9] clk: at91: pmc: Wait for clocks when resuming Ludovic Desroches <ludovic.desroches@microchip.com> - 2017-09-22 14:10 +0200
    Re: [PATCH v2 1/9] clk: at91: pmc: Wait for clocks when resuming Nicolas Ferre <nicolas.ferre@microchip.com> - 2017-09-22 14:20 +0200
  [PATCH v2 5/9] mtd: nand: atmel: Report PMECC failures as errors Romain Izard <romain.izard.pro@gmail.com> - 2017-09-15 16:10 +0200
    Re: [PATCH v2 5/9] mtd: nand: atmel: Report PMECC failures as  errors Boris Brezillon <boris.brezillon@free-electrons.com> - 2017-09-18 12:10 +0200
      Re: [PATCH v2 5/9] mtd: nand: atmel: Report PMECC failures as errors Romain Izard <romain.izard.pro@gmail.com> - 2017-09-21 11:30 +0200
  [PATCH v2 4/9] mtd: nand: atmel: Avoid ECC errors when leaving backup mode Romain Izard <romain.izard.pro@gmail.com> - 2017-09-15 16:10 +0200
    Re: [PATCH v2 4/9] mtd: nand: atmel: Avoid ECC errors when leaving  backup mode Boris Brezillon <boris.brezillon@free-electrons.com> - 2017-09-18 12:00 +0200
  [PATCH v2 2/9] clk: at91: pmc: Save SCSR during suspend Romain Izard <romain.izard.pro@gmail.com> - 2017-09-15 16:10 +0200
  [PATCH v2 8/9] atmel_flexcom: Support backup mode Romain Izard <romain.izard.pro@gmail.com> - 2017-09-15 16:10 +0200
    Re: [PATCH v2 8/9] atmel_flexcom: Support backup mode Nicolas Ferre <nicolas.ferre@microchip.com> - 2017-09-19 11:30 +0200
      Re: [PATCH v2 8/9] atmel_flexcom: Support backup mode Lee Jones <lee.jones@linaro.org> - 2017-09-19 17:30 +0200
        Re: [PATCH v2 8/9] atmel_flexcom: Support backup mode Romain Izard <romain.izard.pro@gmail.com> - 2017-09-20 10:40 +0200
          Re: [PATCH v2 8/9] atmel_flexcom: Support backup mode Alexandre Belloni <alexandre.belloni@free-electrons.com> - 2017-09-20 11:20 +0200
  [PATCH v2 3/9] clk: at91: pmc: Support backup for programmable clocks Romain Izard <romain.izard.pro@gmail.com> - 2017-09-15 16:10 +0200
    Re: [PATCH v2 3/9] clk: at91: pmc: Support backup for programmable  clocks Nicolas Ferre <nicolas.ferre@microchip.com> - 2017-09-22 12:40 +0200
      Re: [PATCH v2 3/9] clk: at91: pmc: Support backup for programmable clocks Romain Izard <romain.izard.pro@gmail.com> - 2017-09-25 10:30 +0200

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