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* [PATCH v3 1/3] NTP: rtc: Add CONFIG_RTC_SYSTOHC_DEVICE for NTP synchronization
@ 2015-06-12  3:10 Xunlei Pang
  2015-06-12  3:10 ` [PATCH v3 2/3] sparc: time: Replace update_persistent_clock() with CONFIG_RTC_SYSTOHC Xunlei Pang
                   ` (2 more replies)
  0 siblings, 3 replies; 6+ messages in thread
From: Xunlei Pang @ 2015-06-12  3:10 UTC (permalink / raw)
  To: linux-kernel
  Cc: rtc-linux, Alessandro Zummo, Alexandre Belloni, John Stultz,
	Arnd Bergmann, David S. Miller, sparclinux, Xunlei Pang,
	Paul Bolle

From: Xunlei Pang <pang.xunlei@linaro.org>

Currently, CONFIG_RTC_SYSTOHC uses CONFIG_RTC_HCTOSYS_DEVICE which
is originally used by CONFIG_RTC_HCTOSYS, but this rtc device has
some limiations, for example, it must be battery-backed, be able
to work with irq off and through system suspension, etc.

So add CONFIG_RTC_SYSTOHC_DEVICE used exclusively for CONFIG_RTC_SYSTOHC,
it is more lenient compared to CONFIG_RTC_HCTOSYS_DEVICE, and could
be assigned any available RTC in the system.

Default value is CONFIG_RTC_HCTOSYS_DEVICE which is "rtc0" by default.
After this patch, NTP will sync up "rtc0" by default.

Cc: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Xunlei Pang <pang.xunlei@linaro.org>
---
 drivers/rtc/Kconfig   | 28 +++++++++++++++++++---------
 drivers/rtc/systohc.c |  2 +-
 2 files changed, 20 insertions(+), 10 deletions(-)

diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index 0fe4ad8..1dcfab4 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -25,17 +25,9 @@ config RTC_HCTOSYS
 	  the value read from a specified RTC device. This is useful to avoid
 	  unnecessary fsck runs at boot time, and to network better.
 
-config RTC_SYSTOHC
-	bool "Set the RTC time based on NTP synchronization"
-	default y
-	help
-	  If you say yes here, the system time (wall clock) will be stored
-	  in the RTC specified by RTC_HCTOSYS_DEVICE approximately every 11
-	  minutes if userspace reports synchronized NTP status.
-
 config RTC_HCTOSYS_DEVICE
 	string "RTC used to set the system time"
-	depends on RTC_HCTOSYS = y || RTC_SYSTOHC = y
+	depends on RTC_HCTOSYS
 	default "rtc0"
 	help
 	  The RTC device that will be used to (re)initialize the system
@@ -56,6 +48,24 @@ config RTC_HCTOSYS_DEVICE
 	  sleep states. Do not specify an RTC here unless it stays powered
 	  during all this system's supported sleep states.
 
+config RTC_SYSTOHC
+	bool "Set the RTC time based on NTP synchronization"
+	default y
+	help
+	  If you say yes here, the system time (wall clock) will be stored
+	  in the RTC specified by RTC_HCTOSYS_DEVICE approximately every 11
+	  minutes if userspace reports synchronized NTP status.
+
+config RTC_SYSTOHC_DEVICE
+	string "RTC used to synchronize NTP adjustment"
+	depends on RTC_SYSTOHC
+	default RTC_HCTOSYS_DEVICE
+	help
+	  The RTC device used for NTP synchronization. The main difference
+	  between RTC_HCTOSYS_DEVICE and RTC_SYSTOHC_DEVICE is that this
+	  one can sleep when setting time, because it runs in the workqueue
+	  context.
+
 config RTC_DEBUG
 	bool "RTC debug support"
 	help
diff --git a/drivers/rtc/systohc.c b/drivers/rtc/systohc.c
index 7728d5e..b4a68ff 100644
--- a/drivers/rtc/systohc.c
+++ b/drivers/rtc/systohc.c
@@ -31,7 +31,7 @@ int rtc_set_ntp_time(struct timespec64 now)
 	else
 		rtc_time64_to_tm(now.tv_sec + 1, &tm);
 
-	rtc = rtc_class_open(CONFIG_RTC_HCTOSYS_DEVICE);
+	rtc = rtc_class_open(CONFIG_RTC_SYSTOHC_DEVICE);
 	if (rtc) {
 		/* rtc_hctosys exclusively uses UTC, so we call set_time here,
 		 * not set_mmss. */
-- 
1.9.1



^ permalink raw reply related	[flat|nested] 6+ messages in thread

* [PATCH v3 2/3] sparc: time: Replace update_persistent_clock() with CONFIG_RTC_SYSTOHC
  2015-06-12  3:10 [PATCH v3 1/3] NTP: rtc: Add CONFIG_RTC_SYSTOHC_DEVICE for NTP synchronization Xunlei Pang
@ 2015-06-12  3:10 ` Xunlei Pang
  2015-06-12  8:42   ` Alexandre Belloni
  2015-06-12  3:10 ` [PATCH v3 3/3] drivers/rtc/interface.c: Remove rtc_set_mmss() Xunlei Pang
  2015-06-13 12:23 ` [PATCH v3 1/3] NTP: rtc: Add CONFIG_RTC_SYSTOHC_DEVICE for NTP synchronization Alexandre Belloni
  2 siblings, 1 reply; 6+ messages in thread
From: Xunlei Pang @ 2015-06-12  3:10 UTC (permalink / raw)
  To: linux-kernel
  Cc: rtc-linux, Alessandro Zummo, Alexandre Belloni, John Stultz,
	Arnd Bergmann, David S. Miller, sparclinux, Xunlei Pang

From: Xunlei Pang <pang.xunlei@linaro.org>

On Sparc systems, update_persistent_clock() uses RTC drivers to do
the job, it makes more sense to hand it over to CONFIG_RTC_SYSTOHC.

In the long run, all the update_persistent_clock() should migrate to
proper class RTC drivers if any and use CONFIG_RTC_SYSTOHC instead.

Signed-off-by: Xunlei Pang <pang.xunlei@linaro.org>
---
 arch/sparc/Kconfig          |  2 +-
 arch/sparc/kernel/time_32.c | 21 ---------------------
 arch/sparc/kernel/time_64.c | 14 --------------
 3 files changed, 1 insertion(+), 36 deletions(-)

diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
index e49502a..56442d2 100644
--- a/arch/sparc/Kconfig
+++ b/arch/sparc/Kconfig
@@ -25,6 +25,7 @@ config SPARC
 	select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
 	select RTC_CLASS
 	select RTC_DRV_M48T59
+	select RTC_SYSTOHC
 	select HAVE_DMA_ATTRS
 	select HAVE_DMA_API_DEBUG
 	select HAVE_ARCH_JUMP_LABEL if SPARC64
@@ -35,7 +36,6 @@ config SPARC
 	select HAVE_BPF_JIT
 	select HAVE_DEBUG_BUGVERBOSE
 	select GENERIC_SMP_IDLE_THREAD
-	select GENERIC_CMOS_UPDATE
 	select GENERIC_CLOCKEVENTS
 	select GENERIC_STRNCPY_FROM_USER
 	select GENERIC_STRNLEN_USER
diff --git a/arch/sparc/kernel/time_32.c b/arch/sparc/kernel/time_32.c
index 8caf45e..c9692f3 100644
--- a/arch/sparc/kernel/time_32.c
+++ b/arch/sparc/kernel/time_32.c
@@ -23,7 +23,6 @@
 #include <linux/mm.h>
 #include <linux/interrupt.h>
 #include <linux/time.h>
-#include <linux/rtc.h>
 #include <linux/rtc/m48t59.h>
 #include <linux/timex.h>
 #include <linux/clocksource.h>
@@ -65,8 +64,6 @@ DEFINE_PER_CPU(struct clock_event_device, sparc32_clockevent);
 DEFINE_SPINLOCK(rtc_lock);
 EXPORT_SYMBOL(rtc_lock);
 
-static int set_rtc_mmss(unsigned long);
-
 unsigned long profile_pc(struct pt_regs *regs)
 {
 	extern char __copy_user_begin[], __copy_user_end[];
@@ -87,11 +84,6 @@ EXPORT_SYMBOL(profile_pc);
 
 volatile u32 __iomem *master_l10_counter;
 
-int update_persistent_clock(struct timespec now)
-{
-	return set_rtc_mmss(now.tv_sec);
-}
-
 irqreturn_t notrace timer_interrupt(int dummy, void *dev_id)
 {
 	if (timer_cs_enabled) {
@@ -362,16 +354,3 @@ void __init time_init(void)
 		sbus_time_init();
 }
 
-
-static int set_rtc_mmss(unsigned long secs)
-{
-	struct rtc_device *rtc = rtc_class_open("rtc0");
-	int err = -1;
-
-	if (rtc) {
-		err = rtc_set_mmss(rtc, secs);
-		rtc_class_close(rtc);
-	}
-
-	return err;
-}
diff --git a/arch/sparc/kernel/time_64.c b/arch/sparc/kernel/time_64.c
index edbbeb1..2e6035c 100644
--- a/arch/sparc/kernel/time_64.c
+++ b/arch/sparc/kernel/time_64.c
@@ -28,7 +28,6 @@
 #include <linux/cpufreq.h>
 #include <linux/percpu.h>
 #include <linux/miscdevice.h>
-#include <linux/rtc.h>
 #include <linux/rtc/m48t59.h>
 #include <linux/kernel_stat.h>
 #include <linux/clockchips.h>
@@ -394,19 +393,6 @@ static struct sparc64_tick_ops hbtick_operations __read_mostly = {
 
 static unsigned long timer_ticks_per_nsec_quotient __read_mostly;
 
-int update_persistent_clock(struct timespec now)
-{
-	struct rtc_device *rtc = rtc_class_open("rtc0");
-	int err = -1;
-
-	if (rtc) {
-		err = rtc_set_mmss(rtc, now.tv_sec);
-		rtc_class_close(rtc);
-	}
-
-	return err;
-}
-
 unsigned long cmos_regs;
 EXPORT_SYMBOL(cmos_regs);
 
-- 
1.9.1



^ permalink raw reply related	[flat|nested] 6+ messages in thread

* [PATCH v3 3/3] drivers/rtc/interface.c: Remove rtc_set_mmss()
  2015-06-12  3:10 [PATCH v3 1/3] NTP: rtc: Add CONFIG_RTC_SYSTOHC_DEVICE for NTP synchronization Xunlei Pang
  2015-06-12  3:10 ` [PATCH v3 2/3] sparc: time: Replace update_persistent_clock() with CONFIG_RTC_SYSTOHC Xunlei Pang
@ 2015-06-12  3:10 ` Xunlei Pang
  2015-06-13 12:23 ` [PATCH v3 1/3] NTP: rtc: Add CONFIG_RTC_SYSTOHC_DEVICE for NTP synchronization Alexandre Belloni
  2 siblings, 0 replies; 6+ messages in thread
From: Xunlei Pang @ 2015-06-12  3:10 UTC (permalink / raw)
  To: linux-kernel
  Cc: rtc-linux, Alessandro Zummo, Alexandre Belloni, John Stultz,
	Arnd Bergmann, David S. Miller, sparclinux, Xunlei Pang

From: Xunlei Pang <pang.xunlei@linaro.org>

Now rtc_set_mmss() has no users, just remove it.

We still have rtc_set_time() doing similar things.

Signed-off-by: Xunlei Pang <pang.xunlei@linaro.org>
---
 drivers/rtc/interface.c | 45 ---------------------------------------------
 include/linux/rtc.h     |  1 -
 2 files changed, 46 deletions(-)

diff --git a/drivers/rtc/interface.c b/drivers/rtc/interface.c
index 166fc60..b511aa1 100644
--- a/drivers/rtc/interface.c
+++ b/drivers/rtc/interface.c
@@ -91,51 +91,6 @@ int rtc_set_time(struct rtc_device *rtc, struct rtc_time *tm)
 }
 EXPORT_SYMBOL_GPL(rtc_set_time);
 
-int rtc_set_mmss(struct rtc_device *rtc, unsigned long secs)
-{
-	int err;
-
-	err = mutex_lock_interruptible(&rtc->ops_lock);
-	if (err)
-		return err;
-
-	if (!rtc->ops)
-		err = -ENODEV;
-	else if (rtc->ops->set_mmss64)
-		err = rtc->ops->set_mmss64(rtc->dev.parent, secs);
-	else if (rtc->ops->set_mmss)
-		err = rtc->ops->set_mmss(rtc->dev.parent, secs);
-	else if (rtc->ops->read_time && rtc->ops->set_time) {
-		struct rtc_time new, old;
-
-		err = rtc->ops->read_time(rtc->dev.parent, &old);
-		if (err == 0) {
-			rtc_time64_to_tm(secs, &new);
-
-			/*
-			 * avoid writing when we're going to change the day of
-			 * the month. We will retry in the next minute. This
-			 * basically means that if the RTC must not drift
-			 * by more than 1 minute in 11 minutes.
-			 */
-			if (!((old.tm_hour == 23 && old.tm_min == 59) ||
-				(new.tm_hour == 23 && new.tm_min == 59)))
-				err = rtc->ops->set_time(rtc->dev.parent,
-						&new);
-		}
-	} else {
-		err = -EINVAL;
-	}
-
-	pm_stay_awake(rtc->dev.parent);
-	mutex_unlock(&rtc->ops_lock);
-	/* A timer might have just expired */
-	schedule_work(&rtc->irqwork);
-
-	return err;
-}
-EXPORT_SYMBOL_GPL(rtc_set_mmss);
-
 static int rtc_read_alarm_internal(struct rtc_device *rtc, struct rtc_wkalrm *alarm)
 {
 	int err;
diff --git a/include/linux/rtc.h b/include/linux/rtc.h
index f46f765..f9c76a8 100644
--- a/include/linux/rtc.h
+++ b/include/linux/rtc.h
@@ -169,7 +169,6 @@ extern void devm_rtc_device_unregister(struct device *dev,
 
 extern int rtc_read_time(struct rtc_device *rtc, struct rtc_time *tm);
 extern int rtc_set_time(struct rtc_device *rtc, struct rtc_time *tm);
-extern int rtc_set_mmss(struct rtc_device *rtc, unsigned long secs);
 extern int rtc_set_ntp_time(struct timespec64 now);
 int __rtc_read_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm);
 extern int rtc_read_alarm(struct rtc_device *rtc,
-- 
1.9.1



^ permalink raw reply related	[flat|nested] 6+ messages in thread

* Re: [PATCH v3 2/3] sparc: time: Replace update_persistent_clock() with CONFIG_RTC_SYSTOHC
  2015-06-12  3:10 ` [PATCH v3 2/3] sparc: time: Replace update_persistent_clock() with CONFIG_RTC_SYSTOHC Xunlei Pang
@ 2015-06-12  8:42   ` Alexandre Belloni
  2015-06-12 18:14     ` David Miller
  0 siblings, 1 reply; 6+ messages in thread
From: Alexandre Belloni @ 2015-06-12  8:42 UTC (permalink / raw)
  To: Xunlei Pang, David S. Miller
  Cc: linux-kernel, rtc-linux, Alessandro Zummo, John Stultz,
	Arnd Bergmann, sparclinux, Xunlei Pang

Dave,

I would like to take that patch as part of the series once you have
acked it.

On 12/06/2015 at 11:10:17 +0800, Xunlei Pang wrote :
> From: Xunlei Pang <pang.xunlei@linaro.org>
> 
> On Sparc systems, update_persistent_clock() uses RTC drivers to do
> the job, it makes more sense to hand it over to CONFIG_RTC_SYSTOHC.
> 
> In the long run, all the update_persistent_clock() should migrate to
> proper class RTC drivers if any and use CONFIG_RTC_SYSTOHC instead.
> 
> Signed-off-by: Xunlei Pang <pang.xunlei@linaro.org>
> ---
>  arch/sparc/Kconfig          |  2 +-
>  arch/sparc/kernel/time_32.c | 21 ---------------------
>  arch/sparc/kernel/time_64.c | 14 --------------
>  3 files changed, 1 insertion(+), 36 deletions(-)
> 
> diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
> index e49502a..56442d2 100644
> --- a/arch/sparc/Kconfig
> +++ b/arch/sparc/Kconfig
> @@ -25,6 +25,7 @@ config SPARC
>  	select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
>  	select RTC_CLASS
>  	select RTC_DRV_M48T59
> +	select RTC_SYSTOHC
>  	select HAVE_DMA_ATTRS
>  	select HAVE_DMA_API_DEBUG
>  	select HAVE_ARCH_JUMP_LABEL if SPARC64
> @@ -35,7 +36,6 @@ config SPARC
>  	select HAVE_BPF_JIT
>  	select HAVE_DEBUG_BUGVERBOSE
>  	select GENERIC_SMP_IDLE_THREAD
> -	select GENERIC_CMOS_UPDATE
>  	select GENERIC_CLOCKEVENTS
>  	select GENERIC_STRNCPY_FROM_USER
>  	select GENERIC_STRNLEN_USER
> diff --git a/arch/sparc/kernel/time_32.c b/arch/sparc/kernel/time_32.c
> index 8caf45e..c9692f3 100644
> --- a/arch/sparc/kernel/time_32.c
> +++ b/arch/sparc/kernel/time_32.c
> @@ -23,7 +23,6 @@
>  #include <linux/mm.h>
>  #include <linux/interrupt.h>
>  #include <linux/time.h>
> -#include <linux/rtc.h>
>  #include <linux/rtc/m48t59.h>
>  #include <linux/timex.h>
>  #include <linux/clocksource.h>
> @@ -65,8 +64,6 @@ DEFINE_PER_CPU(struct clock_event_device, sparc32_clockevent);
>  DEFINE_SPINLOCK(rtc_lock);
>  EXPORT_SYMBOL(rtc_lock);
>  
> -static int set_rtc_mmss(unsigned long);
> -
>  unsigned long profile_pc(struct pt_regs *regs)
>  {
>  	extern char __copy_user_begin[], __copy_user_end[];
> @@ -87,11 +84,6 @@ EXPORT_SYMBOL(profile_pc);
>  
>  volatile u32 __iomem *master_l10_counter;
>  
> -int update_persistent_clock(struct timespec now)
> -{
> -	return set_rtc_mmss(now.tv_sec);
> -}
> -
>  irqreturn_t notrace timer_interrupt(int dummy, void *dev_id)
>  {
>  	if (timer_cs_enabled) {
> @@ -362,16 +354,3 @@ void __init time_init(void)
>  		sbus_time_init();
>  }
>  
> -
> -static int set_rtc_mmss(unsigned long secs)
> -{
> -	struct rtc_device *rtc = rtc_class_open("rtc0");
> -	int err = -1;
> -
> -	if (rtc) {
> -		err = rtc_set_mmss(rtc, secs);
> -		rtc_class_close(rtc);
> -	}
> -
> -	return err;
> -}
> diff --git a/arch/sparc/kernel/time_64.c b/arch/sparc/kernel/time_64.c
> index edbbeb1..2e6035c 100644
> --- a/arch/sparc/kernel/time_64.c
> +++ b/arch/sparc/kernel/time_64.c
> @@ -28,7 +28,6 @@
>  #include <linux/cpufreq.h>
>  #include <linux/percpu.h>
>  #include <linux/miscdevice.h>
> -#include <linux/rtc.h>
>  #include <linux/rtc/m48t59.h>
>  #include <linux/kernel_stat.h>
>  #include <linux/clockchips.h>
> @@ -394,19 +393,6 @@ static struct sparc64_tick_ops hbtick_operations __read_mostly = {
>  
>  static unsigned long timer_ticks_per_nsec_quotient __read_mostly;
>  
> -int update_persistent_clock(struct timespec now)
> -{
> -	struct rtc_device *rtc = rtc_class_open("rtc0");
> -	int err = -1;
> -
> -	if (rtc) {
> -		err = rtc_set_mmss(rtc, now.tv_sec);
> -		rtc_class_close(rtc);
> -	}
> -
> -	return err;
> -}
> -
>  unsigned long cmos_regs;
>  EXPORT_SYMBOL(cmos_regs);
>  
> -- 
> 1.9.1
> 
> 

-- 
Alexandre Belloni, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH v3 2/3] sparc: time: Replace update_persistent_clock() with CONFIG_RTC_SYSTOHC
  2015-06-12  8:42   ` Alexandre Belloni
@ 2015-06-12 18:14     ` David Miller
  0 siblings, 0 replies; 6+ messages in thread
From: David Miller @ 2015-06-12 18:14 UTC (permalink / raw)
  To: alexandre.belloni
  Cc: xlpang, linux-kernel, rtc-linux, a.zummo, john.stultz, arnd,
	sparclinux, pang.xunlei

From: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Date: Fri, 12 Jun 2015 10:42:38 +0200

> I would like to take that patch as part of the series once you have
> acked it.

Sure:

Acked-by: David S. Miller <davem@davemloft.net>

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH v3 1/3] NTP: rtc: Add CONFIG_RTC_SYSTOHC_DEVICE for NTP synchronization
  2015-06-12  3:10 [PATCH v3 1/3] NTP: rtc: Add CONFIG_RTC_SYSTOHC_DEVICE for NTP synchronization Xunlei Pang
  2015-06-12  3:10 ` [PATCH v3 2/3] sparc: time: Replace update_persistent_clock() with CONFIG_RTC_SYSTOHC Xunlei Pang
  2015-06-12  3:10 ` [PATCH v3 3/3] drivers/rtc/interface.c: Remove rtc_set_mmss() Xunlei Pang
@ 2015-06-13 12:23 ` Alexandre Belloni
  2 siblings, 0 replies; 6+ messages in thread
From: Alexandre Belloni @ 2015-06-13 12:23 UTC (permalink / raw)
  To: Xunlei Pang
  Cc: linux-kernel, rtc-linux, Alessandro Zummo, John Stultz,
	Arnd Bergmann, David S. Miller, sparclinux, Xunlei Pang,
	Paul Bolle

Hi,

On 12/06/2015 at 11:10:16 +0800, Xunlei Pang wrote :
> +config RTC_SYSTOHC_DEVICE
> +	string "RTC used to synchronize NTP adjustment"
> +	depends on RTC_SYSTOHC
> +	default RTC_HCTOSYS_DEVICE

Actually, I forgot one case so I changed it to:
+       default RTC_HCTOSYS_DEVICE if RTC_HCTOSYS
+       default "rtc0"

I applied both series, thanks.

-- 
Alexandre Belloni, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com

^ permalink raw reply	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2015-06-13 12:23 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2015-06-12  3:10 [PATCH v3 1/3] NTP: rtc: Add CONFIG_RTC_SYSTOHC_DEVICE for NTP synchronization Xunlei Pang
2015-06-12  3:10 ` [PATCH v3 2/3] sparc: time: Replace update_persistent_clock() with CONFIG_RTC_SYSTOHC Xunlei Pang
2015-06-12  8:42   ` Alexandre Belloni
2015-06-12 18:14     ` David Miller
2015-06-12  3:10 ` [PATCH v3 3/3] drivers/rtc/interface.c: Remove rtc_set_mmss() Xunlei Pang
2015-06-13 12:23 ` [PATCH v3 1/3] NTP: rtc: Add CONFIG_RTC_SYSTOHC_DEVICE for NTP synchronization Alexandre Belloni

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