Merge branch 'fortglx/3.13/time' of git://git.linaro.org/people/jstul…

…tz/linux into timers/core

Pull more timekeeping items for v3.13 from John Stultz:

  * Small cleanup in the clocksource code.

  * Fix for rtc-pl031 to let it work with alarmtimers.

  * Move arm64 to using the generic sched_clock framework & resulting
    cleanup in the generic sched_clock code.

Signed-off-by: Ingo Molnar <mingo@kernel.org>

arch/arm/kernel/arch_timer.c

@@ -11,7 +11,6 @@
 #include <linux/init.h>
 #include <linux/types.h>
 #include <linux/errno.h>
-#include <linux/sched_clock.h>
 
 #include <asm/delay.h>
 
@@ -22,13 +21,6 @@ static unsigned long arch_timer_read_counter_long(void)
 	return arch_timer_read_counter();
 }
 
-static u32 sched_clock_mult __read_mostly;
-
-static unsigned long long notrace arch_timer_sched_clock(void)
-{
-	return arch_timer_read_counter() * sched_clock_mult;
-}
-
 static struct delay_timer arch_delay_timer;
 
 static void __init arch_timer_delay_timer_register(void)
@@ -48,11 +40,5 @@ int __init arch_timer_arch_init(void)
 
 	arch_timer_delay_timer_register();
 
-	/* Cache the sched_clock multiplier to save a divide in the hot path. */
-	sched_clock_mult = NSEC_PER_SEC / arch_timer_rate;
-	sched_clock_func = arch_timer_sched_clock;
-	pr_info("sched_clock: ARM arch timer >56 bits at %ukHz, resolution %uns\n",
-		arch_timer_rate / 1000, sched_clock_mult);
-
 	return 0;
 }

arch/arm64/Kconfig

@@ -14,6 +14,7 @@ config ARM64
 	select GENERIC_IOMAP
 	select GENERIC_IRQ_PROBE
 	select GENERIC_IRQ_SHOW
+	select GENERIC_SCHED_CLOCK
 	select GENERIC_SMP_IDLE_THREAD
 	select GENERIC_TIME_VSYSCALL
 	select HARDIRQS_SW_RESEND

arch/arm64/kernel/time.c

@@ -61,13 +61,6 @@ unsigned long profile_pc(struct pt_regs *regs)
 EXPORT_SYMBOL(profile_pc);
 #endif
 
-static u64 sched_clock_mult __read_mostly;
-
-unsigned long long notrace sched_clock(void)
-{
-	return arch_timer_read_counter() * sched_clock_mult;
-}
-
 void __init time_init(void)
 {
 	u32 arch_timer_rate;
@@ -78,9 +71,6 @@ void __init time_init(void)
 	if (!arch_timer_rate)
 		panic("Unable to initialise architected timer.\n");
 
-	/* Cache the sched_clock multiplier to save a divide in the hot path. */
-	sched_clock_mult = NSEC_PER_SEC / arch_timer_rate;
-
 	/* Calibrate the delay loop directly */
 	lpj_fine = arch_timer_rate / HZ;
 }

drivers/clocksource/arm_arch_timer.c

@@ -20,6 +20,7 @@
 #include <linux/of_address.h>
 #include <linux/io.h>
 #include <linux/slab.h>
+#include <linux/sched_clock.h>
 
 #include <asm/arch_timer.h>
 #include <asm/virt.h>
@@ -514,6 +515,15 @@ static int __init arch_timer_register(void)
 		goto out;
 	}
 
+	clocksource_register_hz(&clocksource_counter, arch_timer_rate);
+	cyclecounter.mult = clocksource_counter.mult;
+	cyclecounter.shift = clocksource_counter.shift;
+	timecounter_init(&timecounter, &cyclecounter,
+			 arch_counter_get_cntvct());
+
+	/* 56 bits minimum, so we assume worst case rollover */
+	sched_clock_register(arch_timer_read_counter, 56, arch_timer_rate);
+
 	if (arch_timer_use_virtual) {
 		ppi = arch_timer_ppi[VIRT_PPI];
 		err = request_percpu_irq(ppi, arch_timer_handler_virt,

drivers/rtc/rtc-pl031.c

@@ -371,6 +371,7 @@ static int pl031_probe(struct amba_device *adev, const struct amba_id *id)
 		}
 	}
 
+	device_init_wakeup(&adev->dev, 1);
 	ldata->rtc = rtc_device_register("pl031", &adev->dev, ops,
 					THIS_MODULE);
 	if (IS_ERR(ldata->rtc)) {
@@ -384,8 +385,6 @@ static int pl031_probe(struct amba_device *adev, const struct amba_id *id)
 		goto out_no_irq;
 	}
 
-	device_init_wakeup(&adev->dev, 1);
-
 	return 0;
 
 out_no_irq:

include/linux/sched_clock.h

@@ -18,6 +18,4 @@ extern void setup_sched_clock(u32 (*read)(void), int bits, unsigned long rate);
 extern void sched_clock_register(u64 (*read)(void), int bits,
 				 unsigned long rate);
 
-extern unsigned long long (*sched_clock_func)(void);
-
 #endif

kernel/time/clocksource.c

@@ -940,7 +940,7 @@ static ssize_t sysfs_override_clocksource(struct device *dev,
 					  struct device_attribute *attr,
 					  const char *buf, size_t count)
 {
-	size_t ret;
+	ssize_t ret;
 
 	mutex_lock(&clocksource_mutex);
 
@@ -968,7 +968,7 @@ static ssize_t sysfs_unbind_clocksource(struct device *dev,
 {
 	struct clocksource *cs;
 	char name[CS_NAME_LEN];
-	size_t ret;
+	ssize_t ret;
 
 	ret = sysfs_get_uname(buf, name, count);
 	if (ret < 0)

kernel/time/sched_clock.c

@@ -63,7 +63,7 @@ static inline u64 notrace cyc_to_ns(u64 cyc, u32 mult, u32 shift)
 	return (cyc * mult) >> shift;
 }
 
-static unsigned long long notrace sched_clock_32(void)
+unsigned long long notrace sched_clock(void)
 {
 	u64 epoch_ns;
 	u64 epoch_cyc;
@@ -170,13 +170,6 @@ void __init setup_sched_clock(u32 (*read)(void), int bits, unsigned long rate)
 	sched_clock_register(read_sched_clock_32_wrapper, bits, rate);
 }
 
-unsigned long long __read_mostly (*sched_clock_func)(void) = sched_clock_32;
-
-unsigned long long notrace sched_clock(void)
-{
-	return sched_clock_func();
-}
-
 void __init sched_clock_postinit(void)
 {
 	/*