diff options
Diffstat (limited to 'arch/arm/mach-omap1/time.c')
| -rw-r--r-- | arch/arm/mach-omap1/time.c | 61 |
1 files changed, 10 insertions, 51 deletions
diff --git a/arch/arm/mach-omap1/time.c b/arch/arm/mach-omap1/time.c index 237651ebae5..5d2b270935a 100644 --- a/arch/arm/mach-omap1/time.c +++ b/arch/arm/mach-omap1/time.c @@ -56,37 +56,6 @@ #define OMAP_MPU_TIMER_BASE OMAP_MPU_TIMER1_BASE #define OMAP_MPU_TIMER_OFFSET 0x100 -/* cycles to nsec conversions taken from arch/i386/kernel/timers/timer_tsc.c, - * converted to use kHz by Kevin Hilman */ -/* convert from cycles(64bits) => nanoseconds (64bits) - * basic equation: - * ns = cycles / (freq / ns_per_sec) - * ns = cycles * (ns_per_sec / freq) - * ns = cycles * (10^9 / (cpu_khz * 10^3)) - * ns = cycles * (10^6 / cpu_khz) - * - * Then we use scaling math (suggested by george at mvista.com) to get: - * ns = cycles * (10^6 * SC / cpu_khz / SC - * ns = cycles * cyc2ns_scale / SC - * - * And since SC is a constant power of two, we can convert the div - * into a shift. - * -johnstul at us.ibm.com "math is hard, lets go shopping!" - */ -static unsigned long cyc2ns_scale; -#define CYC2NS_SCALE_FACTOR 10 /* 2^10, carefully chosen */ - -static inline void set_cyc2ns_scale(unsigned long cpu_khz) -{ - cyc2ns_scale = (1000000 << CYC2NS_SCALE_FACTOR)/cpu_khz; -} - -static inline unsigned long long cycles_2_ns(unsigned long long cyc) -{ - return (cyc * cyc2ns_scale) >> CYC2NS_SCALE_FACTOR; -} - - typedef struct { u32 cntl; /* CNTL_TIMER, R/W */ u32 load_tim; /* LOAD_TIM, W */ @@ -132,13 +101,20 @@ static inline void omap_mpu_timer_start(int nr, unsigned long load_val, timer->cntl = timerflags; } +static inline void omap_mpu_timer_stop(int nr) +{ + volatile omap_mpu_timer_regs_t* timer = omap_mpu_timer_base(nr); + + timer->cntl &= ~MPU_TIMER_ST; +} + /* * --------------------------------------------------------------------------- * MPU timer 1 ... count down to zero, interrupt, reload * --------------------------------------------------------------------------- */ static int omap_mpu_set_next_event(unsigned long cycles, - struct clock_event_device *evt) + struct clock_event_device *evt) { omap_mpu_timer_start(0, cycles, 0); return 0; @@ -152,6 +128,7 @@ static void omap_mpu_set_mode(enum clock_event_mode mode, omap_mpu_set_autoreset(0); break; case CLOCK_EVT_MODE_ONESHOT: + omap_mpu_timer_stop(0); omap_mpu_remove_autoreset(0); break; case CLOCK_EVT_MODE_UNUSED: @@ -163,7 +140,7 @@ static void omap_mpu_set_mode(enum clock_event_mode mode, static struct clock_event_device clockevent_mpu_timer1 = { .name = "mpu_timer1", - .features = CLOCK_EVT_FEAT_PERIODIC, CLOCK_EVT_FEAT_ONESHOT, + .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT, .shift = 32, .set_next_event = omap_mpu_set_next_event, .set_mode = omap_mpu_set_mode, @@ -186,8 +163,6 @@ static struct irqaction omap_mpu_timer1_irq = { static __init void omap_init_mpu_timer(unsigned long rate) { - set_cyc2ns_scale(rate / 1000); - setup_irq(INT_TIMER1, &omap_mpu_timer1_irq); omap_mpu_timer_start(0, (rate / HZ) - 1, 1); @@ -252,22 +227,6 @@ static void __init omap_init_clocksource(unsigned long rate) printk(err, clocksource_mpu.name); } - -/* - * Scheduler clock - returns current time in nanosec units. - */ -unsigned long long sched_clock(void) -{ - unsigned long ticks = 0 - omap_mpu_timer_read(1); - unsigned long long ticks64; - - ticks64 = omap_mpu_timer2_overflows; - ticks64 <<= 32; - ticks64 |= ticks; - - return cycles_2_ns(ticks64); -} - /* * --------------------------------------------------------------------------- * Timer initialization |