diff options
Diffstat (limited to 'arch/mips/kernel/time.c')
| -rw-r--r-- | arch/mips/kernel/time.c | 416 |
1 files changed, 222 insertions, 194 deletions
diff --git a/arch/mips/kernel/time.c b/arch/mips/kernel/time.c index 9a5596bf857..5892491b40e 100644 --- a/arch/mips/kernel/time.c +++ b/arch/mips/kernel/time.c @@ -11,6 +11,7 @@ * Free Software Foundation; either version 2 of the License, or (at your * option) any later version. */ +#include <linux/clockchips.h> #include <linux/types.h> #include <linux/kernel.h> #include <linux/init.h> @@ -24,6 +25,7 @@ #include <linux/spinlock.h> #include <linux/interrupt.h> #include <linux/module.h> +#include <linux/kallsyms.h> #include <asm/bootinfo.h> #include <asm/cache.h> @@ -32,8 +34,11 @@ #include <asm/cpu-features.h> #include <asm/div64.h> #include <asm/sections.h> +#include <asm/smtc_ipi.h> #include <asm/time.h> +#include <irq.h> + /* * The integer part of the number of usecs per jiffy is taken from tick, * but the fractional part is not recorded, so we calculate it using the @@ -49,32 +54,27 @@ * forward reference */ DEFINE_SPINLOCK(rtc_lock); +EXPORT_SYMBOL(rtc_lock); -/* - * By default we provide the null RTC ops - */ -static unsigned long null_rtc_get_time(void) +int __weak rtc_mips_set_time(unsigned long sec) { - return mktime(2000, 1, 1, 0, 0, 0); + return 0; } +EXPORT_SYMBOL(rtc_mips_set_time); -static int null_rtc_set_time(unsigned long sec) +int __weak rtc_mips_set_mmss(unsigned long nowtime) { - return 0; + return rtc_mips_set_time(nowtime); } -unsigned long (*rtc_mips_get_time)(void) = null_rtc_get_time; -int (*rtc_mips_set_time)(unsigned long) = null_rtc_set_time; -int (*rtc_mips_set_mmss)(unsigned long); - +int update_persistent_clock(struct timespec now) +{ + return rtc_mips_set_mmss(now.tv_sec); +} /* how many counter cycles in a jiffy */ static unsigned long cycles_per_jiffy __read_mostly; -/* expirelo is the count value for next CPU timer interrupt */ -static unsigned int expirelo; - - /* * Null timer ack for systems not needing one (e.g. i8254). */ @@ -93,18 +93,7 @@ static cycle_t null_hpt_read(void) */ static void c0_timer_ack(void) { - unsigned int count; - - /* Ack this timer interrupt and set the next one. */ - expirelo += cycles_per_jiffy; - write_c0_compare(expirelo); - - /* Check to see if we have missed any timer interrupts. */ - while (((count = read_c0_count()) - expirelo) < 0x7fffffff) { - /* missed_timer_count++; */ - expirelo = count + cycles_per_jiffy; - write_c0_compare(expirelo); - } + write_c0_compare(read_c0_compare()); } /* @@ -115,19 +104,9 @@ static cycle_t c0_hpt_read(void) return read_c0_count(); } -/* For use both as a high precision timer and an interrupt source. */ -static void __init c0_hpt_timer_init(void) -{ - expirelo = read_c0_count() + cycles_per_jiffy; - write_c0_compare(expirelo); -} - int (*mips_timer_state)(void); void (*mips_timer_ack)(void); -/* last time when xtime and rtc are sync'ed up */ -static long last_rtc_update; - /* * local_timer_interrupt() does profiling and process accounting * on a per-CPU basis. @@ -144,60 +123,15 @@ void local_timer_interrupt(int irq, void *dev_id) update_process_times(user_mode(get_irq_regs())); } -/* - * High-level timer interrupt service routines. This function - * is set as irqaction->handler and is invoked through do_IRQ. - */ -irqreturn_t timer_interrupt(int irq, void *dev_id) -{ - write_seqlock(&xtime_lock); - - mips_timer_ack(); - - /* - * call the generic timer interrupt handling - */ - do_timer(1); - - /* - * If we have an externally synchronized Linux clock, then update - * CMOS clock accordingly every ~11 minutes. rtc_mips_set_time() 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 / 1000) >= 500000 - ((unsigned) TICK_SIZE) / 2 && - (xtime.tv_nsec / 1000) <= 500000 + ((unsigned) TICK_SIZE) / 2) { - if (rtc_mips_set_mmss(xtime.tv_sec) == 0) { - last_rtc_update = xtime.tv_sec; - } else { - /* do it again in 60 s */ - last_rtc_update = xtime.tv_sec - 600; - } - } - - write_sequnlock(&xtime_lock); - - /* - * In UP mode, we call local_timer_interrupt() to do profiling - * and process accouting. - * - * In SMP mode, local_timer_interrupt() is invoked by appropriate - * low-level local timer interrupt handler. - */ - local_timer_interrupt(irq, dev_id); - - return IRQ_HANDLED; -} - int null_perf_irq(void) { return 0; } +EXPORT_SYMBOL(null_perf_irq); + int (*perf_irq)(void) = null_perf_irq; -EXPORT_SYMBOL(null_perf_irq); EXPORT_SYMBOL(perf_irq); /* @@ -215,7 +149,7 @@ EXPORT_SYMBOL_GPL(cp0_perfcount_irq); * Possibly handle a performance counter interrupt. * Return true if the timer interrupt should not be checked */ -static inline int handle_perf_irq (int r2) +static inline int handle_perf_irq(int r2) { /* * The performance counter overflow interrupt may be shared with the @@ -229,63 +163,23 @@ static inline int handle_perf_irq (int r2) !r2; } -asmlinkage void ll_timer_interrupt(int irq) -{ - int r2 = cpu_has_mips_r2; - - irq_enter(); - kstat_this_cpu.irqs[irq]++; - - if (handle_perf_irq(r2)) - goto out; - - if (r2 && ((read_c0_cause() & (1 << 30)) == 0)) - goto out; - - timer_interrupt(irq, NULL); - -out: - irq_exit(); -} - -asmlinkage void ll_local_timer_interrupt(int irq) -{ - irq_enter(); - if (smp_processor_id() != 0) - kstat_this_cpu.irqs[irq]++; - - /* we keep interrupt disabled all the time */ - local_timer_interrupt(irq, NULL); - - irq_exit(); -} - /* * time_init() - it does the following things. * - * 1) board_time_init() - + * 1) plat_time_init() - * a) (optional) set up RTC routines, * b) (optional) calibrate and set the mips_hpt_frequency * (only needed if you intended to use cpu counter as timer interrupt * source) - * 2) setup xtime based on rtc_mips_get_time(). - * 3) calculate a couple of cached variables for later usage - * 4) plat_timer_setup() - + * 2) calculate a couple of cached variables for later usage + * 3) plat_timer_setup() - * a) (optional) over-write any choices made above by time_init(). * b) machine specific code should setup the timer irqaction. * c) enable the timer interrupt */ -void (*board_time_init)(void); - unsigned int mips_hpt_frequency; -static struct irqaction timer_irqaction = { - .handler = timer_interrupt, - .flags = IRQF_DISABLED | IRQF_PERCPU, - .name = "timer", -}; - static unsigned int __init calibrate_hpt(void) { cycle_t frequency, hpt_start, hpt_end, hpt_count, hz; @@ -334,6 +228,84 @@ struct clocksource clocksource_mips = { .flags = CLOCK_SOURCE_IS_CONTINUOUS, }; +static int mips_next_event(unsigned long delta, + struct clock_event_device *evt) +{ + unsigned int cnt; + int res; + +#ifdef CONFIG_MIPS_MT_SMTC + { + unsigned long flags, vpflags; + local_irq_save(flags); + vpflags = dvpe(); +#endif + cnt = read_c0_count(); + cnt += delta; + write_c0_compare(cnt); + res = ((long)(read_c0_count() - cnt ) > 0) ? -ETIME : 0; +#ifdef CONFIG_MIPS_MT_SMTC + evpe(vpflags); + local_irq_restore(flags); + } +#endif + return res; +} + +static void mips_set_mode(enum clock_event_mode mode, + struct clock_event_device *evt) +{ + /* Nothing to do ... */ +} + +static DEFINE_PER_CPU(struct clock_event_device, mips_clockevent_device); +static int cp0_timer_irq_installed; + +static irqreturn_t timer_interrupt(int irq, void *dev_id) +{ + const int r2 = cpu_has_mips_r2; + struct clock_event_device *cd; + int cpu = smp_processor_id(); + + /* + * Suckage alert: + * Before R2 of the architecture there was no way to see if a + * performance counter interrupt was pending, so we have to run + * the performance counter interrupt handler anyway. + */ + if (handle_perf_irq(r2)) + goto out; + + /* + * The same applies to performance counter interrupts. But with the + * above we now know that the reason we got here must be a timer + * interrupt. Being the paranoiacs we are we check anyway. + */ + if (!r2 || (read_c0_cause() & (1 << 30))) { + c0_timer_ack(); +#ifdef CONFIG_MIPS_MT_SMTC + if (cpu_data[cpu].vpe_id) + goto out; + cpu = 0; +#endif + cd = &per_cpu(mips_clockevent_device, cpu); + cd->event_handler(cd); + } + +out: + return IRQ_HANDLED; +} + +static struct irqaction timer_irqaction = { + .handler = timer_interrupt, +#ifdef CONFIG_MIPS_MT_SMTC + .flags = IRQF_DISABLED, +#else + .flags = IRQF_DISABLED | IRQF_PERCPU, +#endif + .name = "timer", +}; + static void __init init_mips_clocksource(void) { u64 temp; @@ -357,19 +329,127 @@ static void __init init_mips_clocksource(void) clocksource_register(&clocksource_mips); } -void __init time_init(void) +void __init __weak plat_time_init(void) +{ +} + +void __init __weak plat_timer_setup(struct irqaction *irq) +{ +} + +#ifdef CONFIG_MIPS_MT_SMTC +DEFINE_PER_CPU(struct clock_event_device, smtc_dummy_clockevent_device); + +static void smtc_set_mode(enum clock_event_mode mode, + struct clock_event_device *evt) +{ +} + +int dummycnt[NR_CPUS]; + +static void mips_broadcast(cpumask_t mask) +{ + unsigned int cpu; + + for_each_cpu_mask(cpu, mask) + smtc_send_ipi(cpu, SMTC_CLOCK_TICK, 0); +} + +static void setup_smtc_dummy_clockevent_device(void) +{ + //uint64_t mips_freq = mips_hpt_^frequency; + unsigned int cpu = smp_processor_id(); + struct clock_event_device *cd; + + cd = &per_cpu(smtc_dummy_clockevent_device, cpu); + + cd->name = "SMTC"; + cd->features = CLOCK_EVT_FEAT_DUMMY; + + /* Calculate the min / max delta */ + cd->mult = 0; //div_sc((unsigned long) mips_freq, NSEC_PER_SEC, 32); + cd->shift = 0; //32; + cd->max_delta_ns = 0; //clockevent_delta2ns(0x7fffffff, cd); + cd->min_delta_ns = 0; //clockevent_delta2ns(0x30, cd); + + cd->rating = 200; + cd->irq = 17; //-1; +// if (cpu) +// cd->cpumask = CPU_MASK_ALL; // cpumask_of_cpu(cpu); +// else + cd->cpumask = cpumask_of_cpu(cpu); + + cd->set_mode = smtc_set_mode; + + cd->broadcast = mips_broadcast; + + clockevents_register_device(cd); +} +#endif + +static void mips_event_handler(struct clock_event_device *dev) { - if (board_time_init) - board_time_init(); +} - if (!rtc_mips_set_mmss) - rtc_mips_set_mmss = rtc_mips_set_time; +void __cpuinit mips_clockevent_init(void) +{ + uint64_t mips_freq = mips_hpt_frequency; + unsigned int cpu = smp_processor_id(); + struct clock_event_device *cd; + unsigned int irq = MIPS_CPU_IRQ_BASE + 7; - xtime.tv_sec = rtc_mips_get_time(); - xtime.tv_nsec = 0; + if (!cpu_has_counter) + return; - set_normalized_timespec(&wall_to_monotonic, - -xtime.tv_sec, -xtime.tv_nsec); +#ifdef CONFIG_MIPS_MT_SMTC + setup_smtc_dummy_clockevent_device(); + + /* + * On SMTC we only register VPE0's compare interrupt as clockevent + * device. + */ + if (cpu) + return; +#endif + + cd = &per_cpu(mips_clockevent_device, cpu); + + cd->name = "MIPS"; + cd->features = CLOCK_EVT_FEAT_ONESHOT; + + /* Calculate the min / max delta */ + cd->mult = div_sc((unsigned long) mips_freq, NSEC_PER_SEC, 32); + cd->shift = 32; + cd->max_delta_ns = clockevent_delta2ns(0x7fffffff, cd); + cd->min_delta_ns = clockevent_delta2ns(0x30, cd); + + cd->rating = 300; + cd->irq = irq; +#ifdef CONFIG_MIPS_MT_SMTC + cd->cpumask = CPU_MASK_ALL; +#else + cd->cpumask = cpumask_of_cpu(cpu); +#endif + cd->set_next_event = mips_next_event; + cd->set_mode = mips_set_mode; + cd->event_handler = mips_event_handler; + + clockevents_register_device(cd); + + if (!cp0_timer_irq_installed) { +#ifdef CONFIG_MIPS_MT_SMTC +#define CPUCTR_IMASKBIT (0x100 << cp0_compare_irq) + setup_irq_smtc(irq, &timer_irqaction, CPUCTR_IMASKBIT); +#else + setup_irq(irq, &timer_irqaction); +#endif /* CONFIG_MIPS_MT_SMTC */ + cp0_timer_irq_installed = 1; + } +} + +void __init time_init(void) +{ + plat_time_init(); /* Choose appropriate high precision timer routines. */ if (!cpu_has_counter && !clocksource_mips.read) @@ -392,11 +472,6 @@ void __init time_init(void) /* Calculate cache parameters. */ cycles_per_jiffy = (mips_hpt_frequency + HZ / 2) / HZ; - /* - * This sets up the high precision - * timer for the first interrupt. - */ - c0_hpt_timer_init(); } } if (!mips_hpt_frequency) @@ -406,6 +481,10 @@ void __init time_init(void) printk("Using %u.%03u MHz high precision timer.\n", ((mips_hpt_frequency + 500) / 1000) / 1000, ((mips_hpt_frequency + 500) / 1000) % 1000); + +#ifdef CONFIG_IRQ_CPU + setup_irq(MIPS_CPU_IRQ_BASE + 7, &timer_irqaction); +#endif } if (!mips_timer_ack) @@ -426,56 +505,5 @@ void __init time_init(void) plat_timer_setup(&timer_irqaction); init_mips_clocksource(); + mips_clockevent_init(); } - -#define FEBRUARY 2 -#define STARTOFTIME 1970 -#define SECDAY 86400L -#define SECYR (SECDAY * 365) -#define leapyear(y) ((!((y) % 4) && ((y) % 100)) || !((y) % 400)) -#define days_in_year(y) (leapyear(y) ? 366 : 365) -#define days_in_month(m) (month_days[(m) - 1]) - -static int month_days[12] = { - 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 -}; - -void to_tm(unsigned long tim, struct rtc_time *tm) -{ - long hms, day, gday; - int i; - - gday = day = tim / SECDAY; - hms = tim % SECDAY; - - /* Hours, minutes, seconds are easy */ - tm->tm_hour = hms / 3600; - tm->tm_min = (hms % 3600) / 60; - tm->tm_sec = (hms % 3600) % 60; - - /* Number of years in days */ - for (i = STARTOFTIME; day >= days_in_year(i); i++) - day -= days_in_year(i); - tm->tm_year = i; - - /* Number of months in days left */ - if (leapyear(tm->tm_year)) - days_in_month(FEBRUARY) = 29; - for (i = 1; day >= days_in_month(i); i++) - day -= days_in_month(i); - days_in_month(FEBRUARY) = 28; - tm->tm_mon = i - 1; /* tm_mon starts from 0 to 11 */ - - /* Days are what is left over (+1) from all that. */ - tm->tm_mday = day + 1; - - /* - * Determine the day of week - */ - tm->tm_wday = (gday + 4) % 7; /* 1970/1/1 was Thursday */ -} - -EXPORT_SYMBOL(rtc_lock); -EXPORT_SYMBOL(to_tm); -EXPORT_SYMBOL(rtc_mips_set_time); -EXPORT_SYMBOL(rtc_mips_get_time); |