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yaml
---
r: 225839
b: refs/heads/master
c: e3f4c0a
h: refs/heads/master
i:
  225837: 3192c4d
  225835: d8d339c
  225831: a359121
  225823: c6a06be
v: v3
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Russell King committed Dec 22, 2010
1 parent d847d91 commit 7a64e04
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Showing 3 changed files with 23 additions and 3 deletions.
2 changes: 1 addition & 1 deletion [refs]
Original file line number Diff line number Diff line change
@@ -1,2 +1,2 @@
---
refs/heads/master: 5094b92f1c7d0f21c5d4411ba7415bac0684210f
refs/heads/master: e3f4c0ab916334e861fc49eeb2673a8c13e978e7
1 change: 1 addition & 0 deletions trunk/arch/arm/Kconfig
Original file line number Diff line number Diff line change
Expand Up @@ -570,6 +570,7 @@ config ARCH_TEGRA
select GENERIC_CLOCKEVENTS
select GENERIC_GPIO
select HAVE_CLK
select HAVE_SCHED_CLOCK
select COMMON_CLKDEV
select ARCH_HAS_BARRIERS if CACHE_L2X0
select ARCH_HAS_CPUFREQ
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23 changes: 21 additions & 2 deletions trunk/arch/arm/mach-tegra/timer.c
Original file line number Diff line number Diff line change
Expand Up @@ -26,10 +26,10 @@
#include <linux/clocksource.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/cnt32_to_63.h>

#include <asm/mach/time.h>
#include <asm/localtimer.h>
#include <asm/sched_clock.h>

#include <mach/iomap.h>
#include <mach/irqs.h>
Expand Down Expand Up @@ -111,9 +111,25 @@ static struct clocksource tegra_clocksource = {
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
};

static DEFINE_CLOCK_DATA(cd);

/*
* Constants generated by clocks_calc_mult_shift(m, s, 1MHz, NSEC_PER_SEC, 60).
* This gives a resolution of about 1us and a wrap period of about 1h11min.
*/
#define SC_MULT 4194304000u
#define SC_SHIFT 22

unsigned long long notrace sched_clock(void)
{
return cnt32_to_63(timer_readl(TIMERUS_CNTR_1US)) * 1000;
u32 cyc = timer_readl(TIMERUS_CNTR_1US);
return cyc_to_fixed_sched_clock(&cd, cyc, (u32)~0, SC_MULT, SC_SHIFT);
}

static void notrace tegra_update_sched_clock(void)
{
u32 cyc = timer_readl(TIMERUS_CNTR_1US);
update_sched_clock(&cd, cyc, (u32)~0);
}

static irqreturn_t tegra_timer_interrupt(int irq, void *dev_id)
Expand Down Expand Up @@ -158,6 +174,9 @@ static void __init tegra_init_timer(void)
WARN(1, "Unknown clock rate");
}

init_fixed_sched_clock(&cd, tegra_update_sched_clock, 32,
1000000, SC_MULT, SC_SHIFT);

if (clocksource_register_hz(&tegra_clocksource, 1000000)) {
printk(KERN_ERR "Failed to register clocksource\n");
BUG();
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