[PATCH V3 5/7] ARM: OMAP3: Update clocksource timer selection

[Igor Grinberg]

On 02/05/13 18:49, Jon Hunter wrote:
> 
> On 02/05/2013 02:39 AM, Igor Grinberg wrote:

[...]

>>
>> Hmmm...
>> Do I miss something or you have forgot to update the commit message?
> 
> Ugh you are right :-(
> 
> Some how yesterday when rebasing the series and adding a couple more
> patches, I royally screwed it up. How about the following ...

Yep, that should do.
Thanks!

> 
> Cheers
> Jon
> 
>>From c82699e94d0255b3b1524e0d5ff4fd1f5852de69 Mon Sep 17 00:00:00 2001
> From: Jon Hunter <jon-hunter at ti.com>
> Date: Mon, 28 Jan 2013 17:53:57 -0600
> Subject: [PATCH] ARM: OMAP3: Update clocksource timer selection
> 
> When booting with device-tree for OMAP3 and AM335x devices and a gptimer
> is used as the clocksource (which is always the case for AM335x), a
> gptimer located in a power domain that is not always-on is selected.
> Ideally we should use a gptimer for clocksource that is located in a
> power domain that is always on (such as the wake-up domain) so that time
> can be maintained during a kernel suspend without keeping on additional
> power domains unnecessarily.
> 
> In order to fix this so that we can select a gptimer located in a power
> domain that is always-on, the following changes were made ...
> 1. Currently, only when selecting a gptimer to use for a clockevent
>    timer, do we pass a timer property that can be used to select a
>    specific gptimer. Change this so that we can pass a property when
>    selecting a gptimer to use for a clocksource timer too.
> 2. Currently, when selecting either a gptimer to use for a clockevent
>    timer or a clocksource timer and no timer property is passed, then
>    the first available timer is selected regardless of the properties
>    it has. Change this so that if no properties are passed, then a timer
>    that does not have additional features (such as always-on, dsp-irq,
>    pwm, and secure) is selected.
> 
> For OMAP3 and AM335x devices that use a gptimer for clocksource, change
> the selection of the gptimer so that by default the gptimer located in
> the always-on power domain is used for clocksource instead of
> clockevents.
> 
> Please note that using a gptimer for both clocksource and clockevents
> can have a system power impact during idle. The reason being is that
> OMAP and AMxxx devices typically only have one gptimer in a power domain
> that is always-on. Therefore when the kernel is idle both the clocksource
> and clockevent timers will be active and this will keep additional power
> domains on. During kernel suspend, only the clocksource timer is active
> and therefore, it is better to use a gptimer in a power domain that is
> always-on for clocksource.
> 
> Signed-off-by: Jon Hunter <jon-hunter at ti.com>
> Acked-by: Santosh Shilimkar <santosh.shilimkar at ti.com>
> Acked-by: Igor Grinberg <grinberg at compulab.co.il>
> ---
>  arch/arm/mach-omap2/timer.c |   33 +++++++++++++++++++++------------
>  1 file changed, 21 insertions(+), 12 deletions(-)
> 
> diff --git a/arch/arm/mach-omap2/timer.c b/arch/arm/mach-omap2/timer.c
> index 3ad9a3b..fce495e 100644
> --- a/arch/arm/mach-omap2/timer.c
> +++ b/arch/arm/mach-omap2/timer.c
> @@ -160,6 +160,12 @@ static struct device_node * __init omap_get_timer_dt(struct of_device_id *match,
>  		if (property && !of_get_property(np, property, NULL))
>  			continue;
>  
> +		if (!property && (of_get_property(np, "ti,timer-alwon", NULL) ||
> +				  of_get_property(np, "ti,timer-dsp", NULL) ||
> +				  of_get_property(np, "ti,timer-pwm", NULL) ||
> +				  of_get_property(np, "ti,timer-secure", NULL)))
> +			continue;
> +
>  		of_add_property(np, &device_disabled);
>  		return np;
>  	}
> @@ -435,13 +441,14 @@ static int __init __maybe_unused omap2_sync32k_clocksource_init(void)
>  }
>  
>  static void __init omap2_gptimer_clocksource_init(int gptimer_id,
> -						const char *fck_source)
> +						  const char *fck_source,
> +						  const char *property)
>  {
>  	int res;
>  
>  	clksrc.errata = omap_dm_timer_get_errata();
>  
> -	res = omap_dm_timer_init_one(&clksrc, gptimer_id, fck_source, NULL,
> +	res = omap_dm_timer_init_one(&clksrc, gptimer_id, fck_source, property,
>  				     &clocksource_gpt.name,
>  				     OMAP_TIMER_NONPOSTED);
>  	BUG_ON(res);
> @@ -538,47 +545,49 @@ static inline void __init realtime_counter_init(void)
>  #endif
>  
>  #define OMAP_SYS_GP_TIMER_INIT(name, clkev_nr, clkev_src, clkev_prop,	\
> -			       clksrc_nr, clksrc_src)			\
> +			       clksrc_nr, clksrc_src, clksrc_prop)	\
>  void __init omap##name##_gptimer_timer_init(void)			\
>  {									\
>  	omap_dmtimer_init();						\
>  	omap2_gp_clockevent_init((clkev_nr), clkev_src, clkev_prop);	\
> -	omap2_gptimer_clocksource_init((clksrc_nr), clksrc_src);	\
> +	omap2_gptimer_clocksource_init((clksrc_nr), clksrc_src,		\
> +					clksrc_prop);			\
>  }
>  
>  #define OMAP_SYS_32K_TIMER_INIT(name, clkev_nr, clkev_src, clkev_prop,	\
> -				clksrc_nr, clksrc_src)			\
> +				clksrc_nr, clksrc_src, clksrc_prop)	\
>  void __init omap##name##_sync32k_timer_init(void)		\
>  {									\
>  	omap_dmtimer_init();						\
>  	omap2_gp_clockevent_init((clkev_nr), clkev_src, clkev_prop);	\
>  	/* Enable the use of clocksource="gp_timer" kernel parameter */	\
>  	if (use_gptimer_clksrc)						\
> -		omap2_gptimer_clocksource_init((clksrc_nr), clksrc_src);\
> +		omap2_gptimer_clocksource_init((clksrc_nr), clksrc_src,	\
> +						clksrc_prop);		\
>  	else								\
>  		omap2_sync32k_clocksource_init();			\
>  }
>  
>  #ifdef CONFIG_ARCH_OMAP2
>  OMAP_SYS_32K_TIMER_INIT(2, 1, "timer_32k_ck", "ti,timer-alwon",
> -			2, "timer_sys_ck");
> +			2, "timer_sys_ck", NULL);
>  #endif /* CONFIG_ARCH_OMAP2 */
>  
>  #ifdef CONFIG_ARCH_OMAP3
>  OMAP_SYS_32K_TIMER_INIT(3, 1, "timer_32k_ck", "ti,timer-alwon",
> -			2, "timer_sys_ck");
> +			2, "timer_sys_ck", NULL);
>  OMAP_SYS_32K_TIMER_INIT(3_secure, 12, "secure_32k_fck", "ti,timer-secure",
> -			2, "timer_sys_ck");
> +			2, "timer_sys_ck", NULL);
>  #endif /* CONFIG_ARCH_OMAP3 */
>  
>  #if defined(CONFIG_ARCH_OMAP3) || defined(CONFIG_SOC_AM33XX)
> -OMAP_SYS_GP_TIMER_INIT(3, 1, "timer_sys_ck", "ti,timer-alwon",
> -		       2, "timer_sys_ck");
> +OMAP_SYS_GP_TIMER_INIT(3, 2, "timer_sys_ck", NULL,
> +		       1, "timer_sys_ck", "ti,timer-alwon");
>  #endif
>  
>  #if defined(CONFIG_ARCH_OMAP4) || defined(CONFIG_SOC_OMAP5)
>  OMAP_SYS_32K_TIMER_INIT(4, 1, "timer_32k_ck", "ti,timer-alwon",
> -			2, "sys_clkin_ck");
> +			2, "sys_clkin_ck", NULL);
>  #endif
>  
>  #ifdef CONFIG_ARCH_OMAP4
> 

-- 
Regards,
Igor.