diff options
Diffstat (limited to 'arch/blackfin/kernel/time.c')
| -rw-r--r-- | arch/blackfin/kernel/time.c | 114 |
1 files changed, 79 insertions, 35 deletions
diff --git a/arch/blackfin/kernel/time.c b/arch/blackfin/kernel/time.c index eb235232045..06de2ce67a9 100644 --- a/arch/blackfin/kernel/time.c +++ b/arch/blackfin/kernel/time.c @@ -34,9 +34,11 @@ #include <linux/interrupt.h> #include <linux/time.h> #include <linux/irq.h> +#include <linux/delay.h> #include <asm/blackfin.h> #include <asm/time.h> +#include <asm/gptimers.h> /* This is an NTP setting */ #define TICK_SIZE (tick_nsec / 1000) @@ -46,11 +48,14 @@ static unsigned long gettimeoffset(void); static struct irqaction bfin_timer_irq = { .name = "BFIN Timer Tick", +#ifdef CONFIG_IRQ_PER_CPU + .flags = IRQF_DISABLED | IRQF_PERCPU, +#else .flags = IRQF_DISABLED +#endif }; -static void -time_sched_init(irq_handler_t timer_routine) +void setup_core_timer(void) { u32 tcount; @@ -71,12 +76,41 @@ time_sched_init(irq_handler_t timer_routine) CSYNC(); bfin_write_TCNTL(7); +} + +#ifdef CONFIG_TICK_SOURCE_SYSTMR0 +void setup_system_timer0(void) +{ + /* Power down the core timer, just to play safe. */ + bfin_write_TCNTL(0); + + disable_gptimers(TIMER0bit); + set_gptimer_status(0, TIMER_STATUS_TRUN0); + while (get_gptimer_status(0) & TIMER_STATUS_TRUN0) + udelay(10); + + set_gptimer_config(0, 0x59); /* IRQ enable, periodic, PWM_OUT, SCLKed, OUT PAD disabled */ + set_gptimer_period(TIMER0_id, get_sclk() / HZ); + set_gptimer_pwidth(TIMER0_id, 1); + SSYNC(); + enable_gptimers(TIMER0bit); +} +#endif +static void +time_sched_init(irqreturn_t(*timer_routine) (int, void *)) +{ +#ifdef CONFIG_TICK_SOURCE_SYSTMR0 + setup_system_timer0(); +#else + setup_core_timer(); +#endif bfin_timer_irq.handler = (irq_handler_t)timer_routine; - /* call setup_irq instead of request_irq because request_irq calls - * kmalloc which has not been initialized yet - */ +#ifdef CONFIG_TICK_SOURCE_SYSTMR0 + setup_irq(IRQ_TIMER0, &bfin_timer_irq); +#else setup_irq(IRQ_CORETMR, &bfin_timer_irq); +#endif } /* @@ -87,17 +121,23 @@ static unsigned long gettimeoffset(void) unsigned long offset; unsigned long clocks_per_jiffy; +#ifdef CONFIG_TICK_SOURCE_SYSTMR0 + clocks_per_jiffy = bfin_read_TIMER0_PERIOD(); + offset = bfin_read_TIMER0_COUNTER() / \ + (((clocks_per_jiffy + 1) * HZ) / USEC_PER_SEC); + + if ((get_gptimer_status(0) & TIMER_STATUS_TIMIL0) && offset < (100000 / HZ / 2)) + offset += (USEC_PER_SEC / HZ); +#else clocks_per_jiffy = bfin_read_TPERIOD(); - offset = - (clocks_per_jiffy - - bfin_read_TCOUNT()) / (((clocks_per_jiffy + 1) * HZ) / - USEC_PER_SEC); + offset = (clocks_per_jiffy - bfin_read_TCOUNT()) / \ + (((clocks_per_jiffy + 1) * HZ) / USEC_PER_SEC); /* Check if we just wrapped the counters and maybe missed a tick */ if ((bfin_read_ILAT() & (1 << IRQ_CORETMR)) - && (offset < (100000 / HZ / 2))) + && (offset < (100000 / HZ / 2))) offset += (USEC_PER_SEC / HZ); - +#endif return offset; } @@ -120,34 +160,38 @@ irqreturn_t timer_interrupt(int irq, void *dummy) static long last_rtc_update; write_seqlock(&xtime_lock); - - do_timer(1); - - profile_tick(CPU_PROFILING); - - /* - * If we have an externally synchronized Linux clock, then update - * CMOS clock accordingly every ~11 minutes. Set_rtc_mmss() has to be - * called as close as possible to 500 ms before the new second starts. - */ - - if (ntp_synced() && - xtime.tv_sec > last_rtc_update + 660 && - (xtime.tv_nsec / NSEC_PER_USEC) >= - 500000 - ((unsigned)TICK_SIZE) / 2 - && (xtime.tv_nsec / NSEC_PER_USEC) <= - 500000 + ((unsigned)TICK_SIZE) / 2) { - if (set_rtc_mmss(xtime.tv_sec) == 0) - last_rtc_update = xtime.tv_sec; - else - /* Do it again in 60s. */ - last_rtc_update = xtime.tv_sec - 600; +#ifdef CONFIG_TICK_SOURCE_SYSTMR0 + if (get_gptimer_status(0) & TIMER_STATUS_TIMIL0) { +#endif + do_timer(1); + + + /* + * If we have an externally synchronized Linux clock, then update + * CMOS clock accordingly every ~11 minutes. Set_rtc_mmss() has to be + * called as close as possible to 500 ms before the new second starts. + */ + + if (ntp_synced() && + xtime.tv_sec > last_rtc_update + 660 && + (xtime.tv_nsec / NSEC_PER_USEC) >= + 500000 - ((unsigned)TICK_SIZE) / 2 + && (xtime.tv_nsec / NSEC_PER_USEC) <= + 500000 + ((unsigned)TICK_SIZE) / 2) { + if (set_rtc_mmss(xtime.tv_sec) == 0) + last_rtc_update = xtime.tv_sec; + else + /* Do it again in 60s. */ + last_rtc_update = xtime.tv_sec - 600; + } +#ifdef CONFIG_TICK_SOURCE_SYSTMR0 + set_gptimer_status(0, TIMER_STATUS_TIMIL0); } +#endif write_sequnlock(&xtime_lock); -#ifndef CONFIG_SMP update_process_times(user_mode(get_irq_regs())); -#endif + profile_tick(CPU_PROFILING); return IRQ_HANDLED; } |