diff options
Diffstat (limited to 'arch/arm/mach-tegra/timer.c')
| -rw-r--r-- | arch/arm/mach-tegra/timer.c | 31 |
1 files changed, 25 insertions, 6 deletions
diff --git a/arch/arm/mach-tegra/timer.c b/arch/arm/mach-tegra/timer.c index 9057d6fd1d31..7b8ad1f98f44 100644 --- a/arch/arm/mach-tegra/timer.c +++ b/arch/arm/mach-tegra/timer.c @@ -18,6 +18,7 @@ */ #include <linux/init.h> +#include <linux/sched.h> #include <linux/time.h> #include <linux/interrupt.h> #include <linux/irq.h> @@ -25,10 +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> @@ -91,7 +92,7 @@ static void tegra_timer_set_mode(enum clock_event_mode mode, static cycle_t tegra_clocksource_read(struct clocksource *cs) { - return cnt32_to_63(timer_readl(TIMERUS_CNTR_1US)); + return timer_readl(TIMERUS_CNTR_1US); } static struct clock_event_device tegra_clockevent = { @@ -106,14 +107,29 @@ static struct clocksource tegra_clocksource = { .name = "timer_us", .rating = 300, .read = tegra_clocksource_read, - .mask = 0x7FFFFFFFFFFFFFFFULL, + .mask = CLOCKSOURCE_MASK(32), .flags = CLOCK_SOURCE_IS_CONTINUOUS, }; -unsigned long long sched_clock(void) +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 clocksource_cyc2ns(tegra_clocksource.read(&tegra_clocksource), - tegra_clocksource.mult, tegra_clocksource.shift); + 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) @@ -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(); |