Re: [PATCH 4/8] ARM: OMAP: 32k counter: Provide y2038-safe omap_read_persistent_clock() replacement

2015-03-11 Thread Tony Lindgren 
* Xunlei Pang  [150310 20:18]:
> From: Xunlei Pang 
> 
> As part of addressing "y2038 problem" for in-kernel uses, this
> patch adds the y2038-safe omap_read_persistent_clock64() using
> timespec64.
> 
> Because we rely on some subsequent changes to convert arm multiarch
> support, omap_read_persistent_clock() will be removed then.
> 
> Also remove the needless spinlock, because read_persistent_clock()
> doesn't run simultaneously.
> 
> Signed-off-by: Xunlei Pang 

Looks OK to me:

Acked-by: Tony Lindgren 

> ---
>  arch/arm/plat-omap/counter_32k.c | 22 --
>  1 file changed, 12 insertions(+), 10 deletions(-)
> 
> diff --git a/arch/arm/plat-omap/counter_32k.c 
> b/arch/arm/plat-omap/counter_32k.c
> index 61b4d70..d422e36 100644
> --- a/arch/arm/plat-omap/counter_32k.c
> +++ b/arch/arm/plat-omap/counter_32k.c
> @@ -44,24 +44,20 @@ static u64 notrace omap_32k_read_sched_clock(void)
>  }
>  
>  /**
> - * omap_read_persistent_clock -  Return time from a persistent clock.
> + * omap_read_persistent_clock64 -  Return time from a persistent clock.
>   *
>   * Reads the time from a source which isn't disabled during PM, the
>   * 32k sync timer.  Convert the cycles elapsed since last read into
> - * nsecs and adds to a monotonically increasing timespec.
> + * nsecs and adds to a monotonically increasing timespec64.
>   */
> -static struct timespec persistent_ts;
> +static struct timespec64 persistent_ts;
>  static cycles_t cycles;
>  static unsigned int persistent_mult, persistent_shift;
> -static DEFINE_SPINLOCK(read_persistent_clock_lock);
>  
> -static void omap_read_persistent_clock(struct timespec *ts)
> +static void omap_read_persistent_clock64(struct timespec64 *ts)
>  {
>   unsigned long long nsecs;
>   cycles_t last_cycles;
> - unsigned long flags;
> -
> - spin_lock_irqsave(_persistent_clock_lock, flags);
>  
>   last_cycles = cycles;
>   cycles = sync32k_cnt_reg ? readl_relaxed(sync32k_cnt_reg) : 0;
> @@ -69,11 +65,17 @@ static void omap_read_persistent_clock(struct timespec 
> *ts)
>   nsecs = clocksource_cyc2ns(cycles - last_cycles,
>   persistent_mult, persistent_shift);
>  
> - timespec_add_ns(_ts, nsecs);
> + timespec64_add_ns(_ts, nsecs);
>  
>   *ts = persistent_ts;
> +}
> +
> +static void omap_read_persistent_clock(struct timespec *ts)
> +{
> + struct timespec64 ts64;
>  
> - spin_unlock_irqrestore(_persistent_clock_lock, flags);
> + omap_read_persistent_clock64();
> + *ts = timespec64_to_timespec(ts64);
>  }
>  
>  /**
> -- 
> 1.9.1
> 
> 
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Re: [PATCH 4/8] ARM: OMAP: 32k counter: Provide y2038-safe omap_read_persistent_clock() replacement

2015-03-11 Thread Tony Lindgren 
* Xunlei Pang xlp...@126.com [150310 20:18]:
 From: Xunlei Pang pang.xun...@linaro.org
 
 As part of addressing y2038 problem for in-kernel uses, this
 patch adds the y2038-safe omap_read_persistent_clock64() using
 timespec64.
 
 Because we rely on some subsequent changes to convert arm multiarch
 support, omap_read_persistent_clock() will be removed then.
 
 Also remove the needless spinlock, because read_persistent_clock()
 doesn't run simultaneously.
 
 Signed-off-by: Xunlei Pang pang.xun...@linaro.org

Looks OK to me:

Acked-by: Tony Lindgren t...@atomide.com

 ---
  arch/arm/plat-omap/counter_32k.c | 22 --
  1 file changed, 12 insertions(+), 10 deletions(-)
 
 diff --git a/arch/arm/plat-omap/counter_32k.c 
 b/arch/arm/plat-omap/counter_32k.c
 index 61b4d70..d422e36 100644
 --- a/arch/arm/plat-omap/counter_32k.c
 +++ b/arch/arm/plat-omap/counter_32k.c
 @@ -44,24 +44,20 @@ static u64 notrace omap_32k_read_sched_clock(void)
  }
  
  /**
 - * omap_read_persistent_clock -  Return time from a persistent clock.
 + * omap_read_persistent_clock64 -  Return time from a persistent clock.
   *
   * Reads the time from a source which isn't disabled during PM, the
   * 32k sync timer.  Convert the cycles elapsed since last read into
 - * nsecs and adds to a monotonically increasing timespec.
 + * nsecs and adds to a monotonically increasing timespec64.
   */
 -static struct timespec persistent_ts;
 +static struct timespec64 persistent_ts;
  static cycles_t cycles;
  static unsigned int persistent_mult, persistent_shift;
 -static DEFINE_SPINLOCK(read_persistent_clock_lock);
  
 -static void omap_read_persistent_clock(struct timespec *ts)
 +static void omap_read_persistent_clock64(struct timespec64 *ts)
  {
   unsigned long long nsecs;
   cycles_t last_cycles;
 - unsigned long flags;
 -
 - spin_lock_irqsave(read_persistent_clock_lock, flags);
  
   last_cycles = cycles;
   cycles = sync32k_cnt_reg ? readl_relaxed(sync32k_cnt_reg) : 0;
 @@ -69,11 +65,17 @@ static void omap_read_persistent_clock(struct timespec 
 *ts)
   nsecs = clocksource_cyc2ns(cycles - last_cycles,
   persistent_mult, persistent_shift);
  
 - timespec_add_ns(persistent_ts, nsecs);
 + timespec64_add_ns(persistent_ts, nsecs);
  
   *ts = persistent_ts;
 +}
 +
 +static void omap_read_persistent_clock(struct timespec *ts)
 +{
 + struct timespec64 ts64;
  
 - spin_unlock_irqrestore(read_persistent_clock_lock, flags);
 + omap_read_persistent_clock64(ts64);
 + *ts = timespec64_to_timespec(ts64);
  }
  
  /**
 -- 
 1.9.1
 
 
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[PATCH 4/8] ARM: OMAP: 32k counter: Provide y2038-safe omap_read_persistent_clock() replacement

2015-03-10 Thread Xunlei Pang 
From: Xunlei Pang 

As part of addressing "y2038 problem" for in-kernel uses, this
patch adds the y2038-safe omap_read_persistent_clock64() using
timespec64.

Because we rely on some subsequent changes to convert arm multiarch
support, omap_read_persistent_clock() will be removed then.

Also remove the needless spinlock, because read_persistent_clock()
doesn't run simultaneously.

Signed-off-by: Xunlei Pang 
---
 arch/arm/plat-omap/counter_32k.c | 22 --
 1 file changed, 12 insertions(+), 10 deletions(-)

diff --git a/arch/arm/plat-omap/counter_32k.c b/arch/arm/plat-omap/counter_32k.c
index 61b4d70..d422e36 100644
--- a/arch/arm/plat-omap/counter_32k.c
+++ b/arch/arm/plat-omap/counter_32k.c
@@ -44,24 +44,20 @@ static u64 notrace omap_32k_read_sched_clock(void)
 }
 
 /**
- * omap_read_persistent_clock -  Return time from a persistent clock.
+ * omap_read_persistent_clock64 -  Return time from a persistent clock.
  *
  * Reads the time from a source which isn't disabled during PM, the
  * 32k sync timer.  Convert the cycles elapsed since last read into
- * nsecs and adds to a monotonically increasing timespec.
+ * nsecs and adds to a monotonically increasing timespec64.
  */
-static struct timespec persistent_ts;
+static struct timespec64 persistent_ts;
 static cycles_t cycles;
 static unsigned int persistent_mult, persistent_shift;
-static DEFINE_SPINLOCK(read_persistent_clock_lock);
 
-static void omap_read_persistent_clock(struct timespec *ts)
+static void omap_read_persistent_clock64(struct timespec64 *ts)
 {
unsigned long long nsecs;
cycles_t last_cycles;
-   unsigned long flags;
-
-   spin_lock_irqsave(_persistent_clock_lock, flags);
 
last_cycles = cycles;
cycles = sync32k_cnt_reg ? readl_relaxed(sync32k_cnt_reg) : 0;
@@ -69,11 +65,17 @@ static void omap_read_persistent_clock(struct timespec *ts)
nsecs = clocksource_cyc2ns(cycles - last_cycles,
persistent_mult, persistent_shift);
 
-   timespec_add_ns(_ts, nsecs);
+   timespec64_add_ns(_ts, nsecs);
 
*ts = persistent_ts;
+}
+
+static void omap_read_persistent_clock(struct timespec *ts)
+{
+   struct timespec64 ts64;
 
-   spin_unlock_irqrestore(_persistent_clock_lock, flags);
+   omap_read_persistent_clock64();
+   *ts = timespec64_to_timespec(ts64);
 }
 
 /**
-- 
1.9.1


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[PATCH 4/8] ARM: OMAP: 32k counter: Provide y2038-safe omap_read_persistent_clock() replacement

2015-03-10 Thread Xunlei Pang 
From: Xunlei Pang pang.xun...@linaro.org

As part of addressing y2038 problem for in-kernel uses, this
patch adds the y2038-safe omap_read_persistent_clock64() using
timespec64.

Because we rely on some subsequent changes to convert arm multiarch
support, omap_read_persistent_clock() will be removed then.

Also remove the needless spinlock, because read_persistent_clock()
doesn't run simultaneously.

Signed-off-by: Xunlei Pang pang.xun...@linaro.org
---
 arch/arm/plat-omap/counter_32k.c | 22 --
 1 file changed, 12 insertions(+), 10 deletions(-)

diff --git a/arch/arm/plat-omap/counter_32k.c b/arch/arm/plat-omap/counter_32k.c
index 61b4d70..d422e36 100644
--- a/arch/arm/plat-omap/counter_32k.c
+++ b/arch/arm/plat-omap/counter_32k.c
@@ -44,24 +44,20 @@ static u64 notrace omap_32k_read_sched_clock(void)
 }
 
 /**
- * omap_read_persistent_clock -  Return time from a persistent clock.
+ * omap_read_persistent_clock64 -  Return time from a persistent clock.
  *
  * Reads the time from a source which isn't disabled during PM, the
  * 32k sync timer.  Convert the cycles elapsed since last read into
- * nsecs and adds to a monotonically increasing timespec.
+ * nsecs and adds to a monotonically increasing timespec64.
  */
-static struct timespec persistent_ts;
+static struct timespec64 persistent_ts;
 static cycles_t cycles;
 static unsigned int persistent_mult, persistent_shift;
-static DEFINE_SPINLOCK(read_persistent_clock_lock);
 
-static void omap_read_persistent_clock(struct timespec *ts)
+static void omap_read_persistent_clock64(struct timespec64 *ts)
 {
unsigned long long nsecs;
cycles_t last_cycles;
-   unsigned long flags;
-
-   spin_lock_irqsave(read_persistent_clock_lock, flags);
 
last_cycles = cycles;
cycles = sync32k_cnt_reg ? readl_relaxed(sync32k_cnt_reg) : 0;
@@ -69,11 +65,17 @@ static void omap_read_persistent_clock(struct timespec *ts)
nsecs = clocksource_cyc2ns(cycles - last_cycles,
persistent_mult, persistent_shift);
 
-   timespec_add_ns(persistent_ts, nsecs);
+   timespec64_add_ns(persistent_ts, nsecs);
 
*ts = persistent_ts;
+}
+
+static void omap_read_persistent_clock(struct timespec *ts)
+{
+   struct timespec64 ts64;
 
-   spin_unlock_irqrestore(read_persistent_clock_lock, flags);
+   omap_read_persistent_clock64(ts64);
+   *ts = timespec64_to_timespec(ts64);
 }
 
 /**
-- 
1.9.1


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