diff options
Diffstat (limited to 'arch/s390/kernel/time.c')
| -rw-r--r-- | arch/s390/kernel/time.c | 1162 |
1 files changed, 828 insertions, 334 deletions
diff --git a/arch/s390/kernel/time.c b/arch/s390/kernel/time.c index 7aec676fefd..0931b110c82 100644 --- a/arch/s390/kernel/time.c +++ b/arch/s390/kernel/time.c @@ -1,9 +1,8 @@ /* - * arch/s390/kernel/time.c * Time of day based timer functions. * * S390 version - * Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation + * Copyright IBM Corp. 1999, 2008 * Author(s): Hartmut Penner (hp@de.ibm.com), * Martin Schwidefsky (schwidefsky@de.ibm.com), * Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com) @@ -12,6 +11,10 @@ * Copyright (C) 1991, 1992, 1995 Linus Torvalds */ +#define KMSG_COMPONENT "time" +#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt + +#include <linux/kernel_stat.h> #include <linux/errno.h> #include <linux/module.h> #include <linux/sched.h> @@ -20,8 +23,10 @@ #include <linux/string.h> #include <linux/mm.h> #include <linux/interrupt.h> +#include <linux/cpu.h> +#include <linux/stop_machine.h> #include <linux/time.h> -#include <linux/sysdev.h> +#include <linux/device.h> #include <linux/delay.h> #include <linux/init.h> #include <linux/smp.h> @@ -29,45 +34,36 @@ #include <linux/profile.h> #include <linux/timex.h> #include <linux/notifier.h> -#include <linux/clocksource.h> +#include <linux/timekeeper_internal.h> #include <linux/clockchips.h> +#include <linux/gfp.h> +#include <linux/kprobes.h> #include <asm/uaccess.h> #include <asm/delay.h> -#include <asm/s390_ext.h> #include <asm/div64.h> +#include <asm/vdso.h> #include <asm/irq.h> #include <asm/irq_regs.h> -#include <asm/timer.h> +#include <asm/vtimer.h> #include <asm/etr.h> #include <asm/cio.h> +#include "entry.h" /* change this if you have some constant time drift */ #define USECS_PER_JIFFY ((unsigned long) 1000000/HZ) #define CLK_TICKS_PER_JIFFY ((unsigned long) USECS_PER_JIFFY << 12) -/* The value of the TOD clock for 1.1.1970. */ -#define TOD_UNIX_EPOCH 0x7d91048bca000000ULL - -/* - * Create a small time difference between the timer interrupts - * on the different cpus to avoid lock contention. - */ -#define CPU_DEVIATION (smp_processor_id() << 12) - -#define TICK_SIZE tick - -static ext_int_info_t ext_int_info_cc; -static ext_int_info_t ext_int_etr_cc; -static u64 jiffies_timer_cc; +u64 sched_clock_base_cc = -1; /* Force to data section. */ +EXPORT_SYMBOL_GPL(sched_clock_base_cc); static DEFINE_PER_CPU(struct clock_event_device, comparators); /* * Scheduler clock - returns current time in nanosec units. */ -unsigned long long sched_clock(void) +unsigned long long notrace __kprobes sched_clock(void) { - return ((get_clock_xt() - jiffies_timer_cc) * 125) >> 9; + return tod_to_ns(get_tod_clock_monotonic()); } /* @@ -79,32 +75,25 @@ unsigned long long monotonic_clock(void) } EXPORT_SYMBOL(monotonic_clock); -void tod_to_timeval(__u64 todval, struct timespec *xtime) +void tod_to_timeval(__u64 todval, struct timespec *xt) { unsigned long long sec; sec = todval >> 12; do_div(sec, 1000000); - xtime->tv_sec = sec; + xt->tv_sec = sec; todval -= (sec * 1000000) << 12; - xtime->tv_nsec = ((todval * 1000) >> 12); + xt->tv_nsec = ((todval * 1000) >> 12); } - -#ifdef CONFIG_PROFILING -#define s390_do_profile() profile_tick(CPU_PROFILING) -#else -#define s390_do_profile() do { ; } while(0) -#endif /* CONFIG_PROFILING */ +EXPORT_SYMBOL(tod_to_timeval); void clock_comparator_work(void) { struct clock_event_device *cd; S390_lowcore.clock_comparator = -1ULL; - set_clock_comparator(S390_lowcore.clock_comparator); cd = &__get_cpu_var(comparators); cd->event_handler(cd); - s390_do_profile(); } /* @@ -122,7 +111,7 @@ static void fixup_clock_comparator(unsigned long long delta) static int s390_next_event(unsigned long delta, struct clock_event_device *evt) { - S390_lowcore.clock_comparator = get_clock() + delta; + S390_lowcore.clock_comparator = get_tod_clock() + delta; set_clock_comparator(S390_lowcore.clock_comparator); return 0; } @@ -153,7 +142,7 @@ void init_cpu_timer(void) cd->min_delta_ns = 1; cd->max_delta_ns = LONG_MAX; cd->rating = 400; - cd->cpumask = cpumask_of_cpu(cpu); + cd->cpumask = cpumask_of(cpu); cd->set_next_event = s390_next_event; cd->set_mode = s390_set_mode; @@ -162,37 +151,48 @@ void init_cpu_timer(void) /* Enable clock comparator timer interrupt. */ __ctl_set_bit(0,11); - /* Always allow ETR external interrupts, even without an ETR. */ + /* Always allow the timing alert external interrupt. */ __ctl_set_bit(0, 4); } -static void clock_comparator_interrupt(__u16 code) +static void clock_comparator_interrupt(struct ext_code ext_code, + unsigned int param32, + unsigned long param64) { + inc_irq_stat(IRQEXT_CLK); + if (S390_lowcore.clock_comparator == -1ULL) + set_clock_comparator(S390_lowcore.clock_comparator); } -static void etr_reset(void); -static void etr_ext_handler(__u16); +static void etr_timing_alert(struct etr_irq_parm *); +static void stp_timing_alert(struct stp_irq_parm *); -/* - * Get the TOD clock running. - */ -static u64 __init reset_tod_clock(void) +static void timing_alert_interrupt(struct ext_code ext_code, + unsigned int param32, unsigned long param64) { - u64 time; + inc_irq_stat(IRQEXT_TLA); + if (param32 & 0x00c40000) + etr_timing_alert((struct etr_irq_parm *) ¶m32); + if (param32 & 0x00038000) + stp_timing_alert((struct stp_irq_parm *) ¶m32); +} - etr_reset(); - if (store_clock(&time) == 0) - return time; - /* TOD clock not running. Set the clock to Unix Epoch. */ - if (set_clock(TOD_UNIX_EPOCH) != 0 || store_clock(&time) != 0) - panic("TOD clock not operational."); +static void etr_reset(void); +static void stp_reset(void); - return TOD_UNIX_EPOCH; +void read_persistent_clock(struct timespec *ts) +{ + tod_to_timeval(get_tod_clock() - TOD_UNIX_EPOCH, ts); } -static cycle_t read_tod_clock(void) +void read_boot_clock(struct timespec *ts) { - return get_clock(); + tod_to_timeval(sched_clock_base_cc - TOD_UNIX_EPOCH, ts); +} + +static cycle_t read_tod_clock(struct clocksource *cs) +{ + return get_tod_clock(); } static struct clocksource clocksource_tod = { @@ -205,6 +205,51 @@ static struct clocksource clocksource_tod = { .flags = CLOCK_SOURCE_IS_CONTINUOUS, }; +struct clocksource * __init clocksource_default_clock(void) +{ + return &clocksource_tod; +} + +void update_vsyscall(struct timekeeper *tk) +{ + u64 nsecps; + + if (tk->clock != &clocksource_tod) + return; + + /* Make userspace gettimeofday spin until we're done. */ + ++vdso_data->tb_update_count; + smp_wmb(); + vdso_data->xtime_tod_stamp = tk->clock->cycle_last; + vdso_data->xtime_clock_sec = tk->xtime_sec; + vdso_data->xtime_clock_nsec = tk->xtime_nsec; + vdso_data->wtom_clock_sec = + tk->xtime_sec + tk->wall_to_monotonic.tv_sec; + vdso_data->wtom_clock_nsec = tk->xtime_nsec + + + ((u64) tk->wall_to_monotonic.tv_nsec << tk->shift); + nsecps = (u64) NSEC_PER_SEC << tk->shift; + while (vdso_data->wtom_clock_nsec >= nsecps) { + vdso_data->wtom_clock_nsec -= nsecps; + vdso_data->wtom_clock_sec++; + } + vdso_data->tk_mult = tk->mult; + vdso_data->tk_shift = tk->shift; + smp_wmb(); + ++vdso_data->tb_update_count; +} + +extern struct timezone sys_tz; + +void update_vsyscall_tz(void) +{ + /* Make userspace gettimeofday spin until we're done. */ + ++vdso_data->tb_update_count; + smp_wmb(); + vdso_data->tz_minuteswest = sys_tz.tz_minuteswest; + vdso_data->tz_dsttime = sys_tz.tz_dsttime; + smp_wmb(); + ++vdso_data->tb_update_count; +} /* * Initialize the TOD clock and the CPU timer of @@ -212,36 +257,152 @@ static struct clocksource clocksource_tod = { */ void __init time_init(void) { - u64 init_timer_cc; - - init_timer_cc = reset_tod_clock(); - jiffies_timer_cc = init_timer_cc - jiffies_64 * CLK_TICKS_PER_JIFFY; - - /* set xtime */ - tod_to_timeval(init_timer_cc - TOD_UNIX_EPOCH, &xtime); - set_normalized_timespec(&wall_to_monotonic, - -xtime.tv_sec, -xtime.tv_nsec); + /* Reset time synchronization interfaces. */ + etr_reset(); + stp_reset(); /* request the clock comparator external interrupt */ - if (register_early_external_interrupt(0x1004, - clock_comparator_interrupt, - &ext_int_info_cc) != 0) - panic("Couldn't request external interrupt 0x1004"); + if (register_external_irq(EXT_IRQ_CLK_COMP, clock_comparator_interrupt)) + panic("Couldn't request external interrupt 0x1004"); + + /* request the timing alert external interrupt */ + if (register_external_irq(EXT_IRQ_TIMING_ALERT, timing_alert_interrupt)) + panic("Couldn't request external interrupt 0x1406"); if (clocksource_register(&clocksource_tod) != 0) panic("Could not register TOD clock source"); - /* request the etr external interrupt */ - if (register_early_external_interrupt(0x1406, etr_ext_handler, - &ext_int_etr_cc) != 0) - panic("Couldn't request external interrupt 0x1406"); - /* Enable TOD clock interrupts on the boot cpu. */ init_cpu_timer(); -#ifdef CONFIG_VIRT_TIMER + /* Enable cpu timer interrupts on the boot cpu. */ vtime_init(); -#endif +} + +/* + * The time is "clock". old is what we think the time is. + * Adjust the value by a multiple of jiffies and add the delta to ntp. + * "delay" is an approximation how long the synchronization took. If + * the time correction is positive, then "delay" is subtracted from + * the time difference and only the remaining part is passed to ntp. + */ +static unsigned long long adjust_time(unsigned long long old, + unsigned long long clock, + unsigned long long delay) +{ + unsigned long long delta, ticks; + struct timex adjust; + + if (clock > old) { + /* It is later than we thought. */ + delta = ticks = clock - old; + delta = ticks = (delta < delay) ? 0 : delta - delay; + delta -= do_div(ticks, CLK_TICKS_PER_JIFFY); + adjust.offset = ticks * (1000000 / HZ); + } else { + /* It is earlier than we thought. */ + delta = ticks = old - clock; + delta -= do_div(ticks, CLK_TICKS_PER_JIFFY); + delta = -delta; + adjust.offset = -ticks * (1000000 / HZ); + } + sched_clock_base_cc += delta; + if (adjust.offset != 0) { + pr_notice("The ETR interface has adjusted the clock " + "by %li microseconds\n", adjust.offset); + adjust.modes = ADJ_OFFSET_SINGLESHOT; + do_adjtimex(&adjust); + } + return delta; +} + +static DEFINE_PER_CPU(atomic_t, clock_sync_word); +static DEFINE_MUTEX(clock_sync_mutex); +static unsigned long clock_sync_flags; + +#define CLOCK_SYNC_HAS_ETR 0 +#define CLOCK_SYNC_HAS_STP 1 +#define CLOCK_SYNC_ETR 2 +#define CLOCK_SYNC_STP 3 + +/* + * The synchronous get_clock function. It will write the current clock + * value to the clock pointer and return 0 if the clock is in sync with + * the external time source. If the clock mode is local it will return + * -EOPNOTSUPP and -EAGAIN if the clock is not in sync with the external + * reference. + */ +int get_sync_clock(unsigned long long *clock) +{ + atomic_t *sw_ptr; + unsigned int sw0, sw1; + + sw_ptr = &get_cpu_var(clock_sync_word); + sw0 = atomic_read(sw_ptr); + *clock = get_tod_clock(); + sw1 = atomic_read(sw_ptr); + put_cpu_var(clock_sync_word); + if (sw0 == sw1 && (sw0 & 0x80000000U)) + /* Success: time is in sync. */ + return 0; + if (!test_bit(CLOCK_SYNC_HAS_ETR, &clock_sync_flags) && + !test_bit(CLOCK_SYNC_HAS_STP, &clock_sync_flags)) + return -EOPNOTSUPP; + if (!test_bit(CLOCK_SYNC_ETR, &clock_sync_flags) && + !test_bit(CLOCK_SYNC_STP, &clock_sync_flags)) + return -EACCES; + return -EAGAIN; +} +EXPORT_SYMBOL(get_sync_clock); + +/* + * Make get_sync_clock return -EAGAIN. + */ +static void disable_sync_clock(void *dummy) +{ + atomic_t *sw_ptr = &__get_cpu_var(clock_sync_word); + /* + * Clear the in-sync bit 2^31. All get_sync_clock calls will + * fail until the sync bit is turned back on. In addition + * increase the "sequence" counter to avoid the race of an + * etr event and the complete recovery against get_sync_clock. + */ + atomic_clear_mask(0x80000000, sw_ptr); + atomic_inc(sw_ptr); +} + +/* + * Make get_sync_clock return 0 again. + * Needs to be called from a context disabled for preemption. + */ +static void enable_sync_clock(void) +{ + atomic_t *sw_ptr = &__get_cpu_var(clock_sync_word); + atomic_set_mask(0x80000000, sw_ptr); +} + +/* + * Function to check if the clock is in sync. + */ +static inline int check_sync_clock(void) +{ + atomic_t *sw_ptr; + int rc; + + sw_ptr = &get_cpu_var(clock_sync_word); + rc = (atomic_read(sw_ptr) & 0x80000000U) != 0; + put_cpu_var(clock_sync_word); + return rc; +} + +/* Single threaded workqueue used for etr and stp sync events */ +static struct workqueue_struct *time_sync_wq; + +static void __init time_init_wq(void) +{ + if (time_sync_wq) + return; + time_sync_wq = create_singlethread_workqueue("timesync"); } /* @@ -249,6 +410,7 @@ void __init time_init(void) */ static int etr_port0_online; static int etr_port1_online; +static int etr_steai_available; static int __init early_parse_etr(char *p) { @@ -273,12 +435,6 @@ enum etr_event { ETR_EVENT_UPDATE, }; -enum etr_flags { - ETR_FLAG_ENOSYS, - ETR_FLAG_EACCES, - ETR_FLAG_STEAI, -}; - /* * Valid bit combinations of the eacr register are (x = don't care): * e0 e1 dp p0 p1 ea es sl @@ -305,74 +461,19 @@ enum etr_flags { */ static struct etr_eacr etr_eacr; static u64 etr_tolec; /* time of last eacr update */ -static unsigned long etr_flags; static struct etr_aib etr_port0; static int etr_port0_uptodate; static struct etr_aib etr_port1; static int etr_port1_uptodate; static unsigned long etr_events; static struct timer_list etr_timer; -static DEFINE_PER_CPU(atomic_t, etr_sync_word); static void etr_timeout(unsigned long dummy); static void etr_work_fn(struct work_struct *work); +static DEFINE_MUTEX(etr_work_mutex); static DECLARE_WORK(etr_work, etr_work_fn); /* - * The etr get_clock function. It will write the current clock value - * to the clock pointer and return 0 if the clock is in sync with the - * external time source. If the clock mode is local it will return - * -ENOSYS and -EAGAIN if the clock is not in sync with the external - * reference. This function is what ETR is all about.. - */ -int get_sync_clock(unsigned long long *clock) -{ - atomic_t *sw_ptr; - unsigned int sw0, sw1; - - sw_ptr = &get_cpu_var(etr_sync_word); - sw0 = atomic_read(sw_ptr); - *clock = get_clock(); - sw1 = atomic_read(sw_ptr); - put_cpu_var(etr_sync_sync); - if (sw0 == sw1 && (sw0 & 0x80000000U)) - /* Success: time is in sync. */ - return 0; - if (test_bit(ETR_FLAG_ENOSYS, &etr_flags)) - return -ENOSYS; - if (test_bit(ETR_FLAG_EACCES, &etr_flags)) - return -EACCES; - return -EAGAIN; -} -EXPORT_SYMBOL(get_sync_clock); - -/* - * Make get_sync_clock return -EAGAIN. - */ -static void etr_disable_sync_clock(void *dummy) -{ - atomic_t *sw_ptr = &__get_cpu_var(etr_sync_word); - /* - * Clear the in-sync bit 2^31. All get_sync_clock calls will - * fail until the sync bit is turned back on. In addition - * increase the "sequence" counter to avoid the race of an - * etr event and the complete recovery against get_sync_clock. - */ - atomic_clear_mask(0x80000000, sw_ptr); - atomic_inc(sw_ptr); -} - -/* - * Make get_sync_clock return 0 again. - * Needs to be called from a context disabled for preemption. - */ -static void etr_enable_sync_clock(void) -{ - atomic_t *sw_ptr = &__get_cpu_var(etr_sync_word); - atomic_set_mask(0x80000000, sw_ptr); -} - -/* * Reset ETR attachment. */ static void etr_reset(void) @@ -381,15 +482,15 @@ static void etr_reset(void) .e0 = 0, .e1 = 0, ._pad0 = 4, .dp = 0, .p0 = 0, .p1 = 0, ._pad1 = 0, .ea = 0, .es = 0, .sl = 0 }; - if (etr_setr(&etr_eacr) == 0) - etr_tolec = get_clock(); - else { - set_bit(ETR_FLAG_ENOSYS, &etr_flags); - if (etr_port0_online || etr_port1_online) { - printk(KERN_WARNING "Running on non ETR capable " - "machine, only local mode available.\n"); - etr_port0_online = etr_port1_online = 0; - } + if (etr_setr(&etr_eacr) == 0) { + etr_tolec = get_tod_clock(); + set_bit(CLOCK_SYNC_HAS_ETR, &clock_sync_flags); + if (etr_port0_online && etr_port1_online) + set_bit(CLOCK_SYNC_ETR, &clock_sync_flags); + } else if (etr_port0_online || etr_port1_online) { + pr_warning("The real or virtual hardware system does " + "not provide an ETR interface\n"); + etr_port0_online = etr_port1_online = 0; } } @@ -397,21 +498,20 @@ static int __init etr_init(void) { struct etr_aib aib; - if (test_bit(ETR_FLAG_ENOSYS, &etr_flags)) + if (!test_bit(CLOCK_SYNC_HAS_ETR, &clock_sync_flags)) return 0; + time_init_wq(); /* Check if this machine has the steai instruction. */ if (etr_steai(&aib, ETR_STEAI_STEPPING_PORT) == 0) - set_bit(ETR_FLAG_STEAI, &etr_flags); + etr_steai_available = 1; setup_timer(&etr_timer, etr_timeout, 0UL); - if (!etr_port0_online && !etr_port1_online) - set_bit(ETR_FLAG_EACCES, &etr_flags); if (etr_port0_online) { set_bit(ETR_EVENT_PORT0_CHANGE, &etr_events); - schedule_work(&etr_work); + queue_work(time_sync_wq, &etr_work); } if (etr_port1_online) { set_bit(ETR_EVENT_PORT1_CHANGE, &etr_events); - schedule_work(&etr_work); + queue_work(time_sync_wq, &etr_work); } return 0; } @@ -435,9 +535,12 @@ void etr_switch_to_local(void) { if (!etr_eacr.sl) return; - etr_disable_sync_clock(NULL); - set_bit(ETR_EVENT_SWITCH_LOCAL, &etr_events); - schedule_work(&etr_work); + disable_sync_clock(NULL); + if (!test_and_set_bit(ETR_EVENT_SWITCH_LOCAL, &etr_events)) { + etr_eacr.es = etr_eacr.sl = 0; + etr_setr(&etr_eacr); + queue_work(time_sync_wq, &etr_work); + } } /* @@ -450,23 +553,23 @@ void etr_sync_check(void) { if (!etr_eacr.es) return; - etr_disable_sync_clock(NULL); - set_bit(ETR_EVENT_SYNC_CHECK, &etr_events); - schedule_work(&etr_work); + disable_sync_clock(NULL); + if (!test_and_set_bit(ETR_EVENT_SYNC_CHECK, &etr_events)) { + etr_eacr.es = 0; + etr_setr(&etr_eacr); + queue_work(time_sync_wq, &etr_work); + } } /* - * ETR external interrupt. There are two causes: + * ETR timing alert. There are two causes: * 1) port state change, check the usability of the port * 2) port alert, one of the ETR-data-validity bits (v1-v2 bits of the * sldr-status word) or ETR-data word 1 (edf1) or ETR-data word 3 (edf3) * or ETR-data word 4 (edf4) has changed. */ -static void etr_ext_handler(__u16 code) +static void etr_timing_alert(struct etr_irq_parm *intparm) { - struct etr_interruption_parameter *intparm = - (struct etr_interruption_parameter *) &S390_lowcore.ext_params; - if (intparm->pc0) /* ETR port 0 state change. */ set_bit(ETR_EVENT_PORT0_CHANGE, &etr_events); @@ -479,13 +582,13 @@ static void etr_ext_handler(__u16 code) * Both ports are not up-to-date now. */ set_bit(ETR_EVENT_PORT_ALERT, &etr_events); - schedule_work(&etr_work); + queue_work(time_sync_wq, &etr_work); } static void etr_timeout(unsigned long dummy) { set_bit(ETR_EVENT_UPDATE, &etr_events); - schedule_work(&etr_work); + queue_work(time_sync_wq, &etr_work); } /* @@ -591,58 +694,25 @@ static int etr_aib_follows(struct etr_aib *a1, struct etr_aib *a2, int p) return 1; } -/* - * The time is "clock". old is what we think the time is. - * Adjust the value by a multiple of jiffies and add the delta to ntp. - * "delay" is an approximation how long the synchronization took. If - * the time correction is positive, then "delay" is subtracted from - * the time difference and only the remaining part is passed to ntp. - */ -static unsigned long long etr_adjust_time(unsigned long long old, - unsigned long long clock, - unsigned long long delay) -{ - unsigned long long delta, ticks; - struct timex adjust; - - if (clock > old) { - /* It is later than we thought. */ - delta = ticks = clock - old; - delta = ticks = (delta < delay) ? 0 : delta - delay; - delta -= do_div(ticks, CLK_TICKS_PER_JIFFY); - adjust.offset = ticks * (1000000 / HZ); - } else { - /* It is earlier than we thought. */ - delta = ticks = old - clock; - delta -= do_div(ticks, CLK_TICKS_PER_JIFFY); - delta = -delta; - adjust.offset = -ticks * (1000000 / HZ); - } - jiffies_timer_cc += delta; - if (adjust.offset != 0) { - printk(KERN_NOTICE "etr: time adjusted by %li micro-seconds\n", - adjust.offset); - adjust.modes = ADJ_OFFSET_SINGLESHOT; - do_adjtimex(&adjust); - } - return delta; -} - -static struct { +struct clock_sync_data { + atomic_t cpus; int in_sync; unsigned long long fixup_cc; -} etr_sync; + int etr_port; + struct etr_aib *etr_aib; +}; -static void etr_sync_cpu_start(void *dummy) +static void clock_sync_cpu(struct clock_sync_data *sync) { - etr_enable_sync_clock(); + atomic_dec(&sync->cpus); + enable_sync_clock(); /* * This looks like a busy wait loop but it isn't. etr_sync_cpus * is called on all other cpus while the TOD clocks is stopped. * __udelay will stop the cpu on an enabled wait psw until the * TOD is running again. */ - while (etr_sync.in_sync == 0) { + while (sync->in_sync == 0) { __udelay(1); /* * A different cpu changes *in_sync. Therefore use @@ -650,56 +720,53 @@ static void etr_sync_cpu_start(void *dummy) */ barrier(); } - if (etr_sync.in_sync != 1) + if (sync->in_sync != 1) /* Didn't work. Clear per-cpu in sync bit again. */ - etr_disable_sync_clock(NULL); + disable_sync_clock(NULL); /* * This round of TOD syncing is done. Set the clock comparator * to the next tick and let the processor continue. */ - fixup_clock_comparator(etr_sync.fixup_cc); -} - -static void etr_sync_cpu_end(void *dummy) -{ + fixup_clock_comparator(sync->fixup_cc); } /* - * Sync the TOD clock using the port refered to by aibp. This port + * Sync the TOD clock using the port referred to by aibp. This port * has to be enabled and the other port has to be disabled. The * last eacr update has to be more than 1.6 seconds in the past. */ -static int etr_sync_clock(struct etr_aib *aib, int port) +static int etr_sync_clock(void *data) { - struct etr_aib *sync_port; + static int first; unsigned long long clock, old_clock, delay, delta; - int follows; + struct clock_sync_data *etr_sync; + struct etr_aib *sync_port, *aib; + int port; int rc; - /* Check if the current aib is adjacent to the sync port aib. */ - sync_port = (port == 0) ? &etr_port0 : &etr_port1; - follows = etr_aib_follows(sync_port, aib, port); - memcpy(sync_port, aib, sizeof(*aib)); - if (!follows) - return -EAGAIN; + etr_sync = data; - /* - * Catch all other cpus and make them wait until we have - * successfully synced the clock. smp_call_function will - * return after all other cpus are in etr_sync_cpu_start. - */ - memset(&etr_sync, 0, sizeof(etr_sync)); - preempt_disable(); - smp_call_function(etr_sync_cpu_start, NULL, 0, 0); - local_irq_disable(); - etr_enable_sync_clock(); + if (xchg(&first, 1) == 1) { + /* Slave */ + clock_sync_cpu(etr_sync); + return 0; + } + + /* Wait until all other cpus entered the sync function. */ + while (atomic_read(&etr_sync->cpus) != 0) + cpu_relax(); + + port = etr_sync->etr_port; + aib = etr_sync->etr_aib; + sync_port = (port == 0) ? &etr_port0 : &etr_port1; + enable_sync_clock(); /* Set clock to next OTE. */ __ctl_set_bit(14, 21); __ctl_set_bit(0, 29); clock = ((unsigned long long) (aib->edf2.etv + 1)) << 32; - old_clock = get_clock(); - if (set_clock(clock) == 0) { + old_clock = get_tod_clock(); + if (set_tod_clock(clock) == 0) { __udelay(1); /* Wait for the clock to start. */ __ctl_clear_bit(0, 29); __ctl_clear_bit(14, 21); @@ -707,30 +774,51 @@ static int etr_sync_clock(struct etr_aib *aib, int port) /* Adjust Linux timing variables. */ delay = (unsigned long long) (aib->edf2.etv - sync_port->edf2.etv) << 32; - delta = etr_adjust_time(old_clock, clock, delay); - etr_sync.fixup_cc = delta; + delta = adjust_time(old_clock, clock, delay); + etr_sync->fixup_cc = delta; fixup_clock_comparator(delta); /* Verify that the clock is properly set. */ if (!etr_aib_follows(sync_port, aib, port)) { /* Didn't work. */ - etr_disable_sync_clock(NULL); - etr_sync.in_sync = -EAGAIN; + disable_sync_clock(NULL); + etr_sync->in_sync = -EAGAIN; rc = -EAGAIN; } else { - etr_sync.in_sync = 1; + etr_sync->in_sync = 1; rc = 0; } } else { /* Could not set the clock ?!? */ __ctl_clear_bit(0, 29); __ctl_clear_bit(14, 21); - etr_disable_sync_clock(NULL); - etr_sync.in_sync = -EAGAIN; + disable_sync_clock(NULL); + etr_sync->in_sync = -EAGAIN; rc = -EAGAIN; } - local_irq_enable(); - smp_call_function(etr_sync_cpu_end,NULL,0,0); - preempt_enable(); + xchg(&first, 0); + return rc; +} + +static int etr_sync_clock_stop(struct etr_aib *aib, int port) +{ + struct clock_sync_data etr_sync; + struct etr_aib *sync_port; + int follows; + int rc; + + /* Check if the current aib is adjacent to the sync port aib. */ + sync_port = (port == 0) ? &etr_port0 : &etr_port1; + follows = etr_aib_follows(sync_port, aib, port); + memcpy(sync_port, aib, sizeof(*aib)); + if (!follows) + return -EAGAIN; + memset(&etr_sync, 0, sizeof(etr_sync)); + etr_sync.etr_aib = aib; + etr_sync.etr_port = port; + get_online_cpus(); + atomic_set(&etr_sync.cpus, num_online_cpus() - 1); + rc = stop_machine(etr_sync_clock, &etr_sync, cpu_online_mask); + put_online_cpus(); return rc; } @@ -754,7 +842,7 @@ static struct etr_eacr etr_handle_events(struct etr_eacr eacr) * assume that this can have caused an stepping * port switch. */ - etr_tolec = get_clock(); + etr_tolec = get_tod_clock(); eacr.p0 = etr_port0_online; if (!eacr.p0) eacr.e0 = 0; @@ -767,7 +855,7 @@ static struct etr_eacr etr_handle_events(struct etr_eacr eacr) * assume that this can have caused an stepping * port switch. */ - etr_tolec = get_clock(); + etr_tolec = get_tod_clock(); eacr.p1 = etr_port1_online; if (!eacr.p1) eacr.e1 = 0; @@ -832,7 +920,7 @@ static struct etr_eacr etr_handle_update(struct etr_aib *aib, * Do not try to get the alternate port aib if the clock * is not in sync yet. */ - if (!eacr.es) + if (!eacr.es || !check_sync_clock()) return eacr; /* @@ -840,7 +928,7 @@ static struct etr_eacr etr_handle_update(struct etr_aib *aib, * the other port immediately. If only stetr is available the * data-port bit toggle has to be used. */ - if (test_bit(ETR_FLAG_STEAI, &etr_flags)) { + if (etr_steai_available) { if (eacr.p0 && !etr_port0_uptodate) { etr_steai_cv(&etr_port0, ETR_STEAI_PORT_0); etr_port0_uptodate = 1; @@ -883,11 +971,11 @@ static void etr_update_eacr(struct etr_eacr eacr) etr_eacr = eacr; etr_setr(&etr_eacr); if (dp_changed) - etr_tolec = get_clock(); + etr_tolec = get_tod_clock(); } /* - * ETR tasklet. In this function you'll find the main logic. In + * ETR work. In this function you'll find the main logic. In * particular this is the only function that calls etr_update_eacr(), * it "controls" the etr control register. */ @@ -898,6 +986,9 @@ static void etr_work_fn(struct work_struct *work) struct etr_aib aib; int sync_port; + /* prevent multiple execution. */ + mutex_lock(&etr_work_mutex); + /* Create working copy of etr_eacr. */ eacr = etr_eacr; @@ -909,17 +1000,16 @@ static void etr_work_fn(struct work_struct *work) if (!eacr.ea) { /* Both ports offline. Reset everything. */ eacr.dp = eacr.es = eacr.sl = 0; - on_each_cpu(etr_disable_sync_clock, NULL, 0, 1); + on_each_cpu(disable_sync_clock, NULL, 1); del_timer_sync(&etr_timer); etr_update_eacr(eacr); - set_bit(ETR_FLAG_EACCES, &etr_flags); - return; + goto out_unlock; } /* Store aib to get the current ETR status word. */ BUG_ON(etr_stetr(&aib) != 0); etr_port0.esw = etr_port1.esw = aib.esw; /* Copy status word. */ - now = get_clock(); + now = get_tod_clock(); /* * Update the port information if the last stepping port change @@ -929,7 +1019,7 @@ static void etr_work_fn(struct work_struct *work) eacr = etr_handle_update(&aib, eacr); /* - * Select ports to enable. The prefered synchronization mode is PPS. + * Select ports to enable. The preferred synchronization mode is PPS. * If a port can be enabled depends on a number of things: * 1) The port needs to be online and uptodate. A port is not * disabled just because it is not uptodate, but it is only @@ -953,7 +1043,6 @@ static void etr_work_fn(struct work_struct *work) eacr.e1 = 1; sync_port = (etr_port0_uptodate && etr_port_valid(&etr_port0, 0)) ? 0 : -1; - clear_bit(ETR_FLAG_EACCES, &etr_flags); } else if (eacr.p1 && aib.esw.psc1 == etr_lpsc_pps_mode) { eacr.sl = 0; eacr.e0 = 0; @@ -962,7 +1051,6 @@ static void etr_work_fn(struct work_struct *work) eacr.es = 0; sync_port = (etr_port1_uptodate && etr_port_valid(&etr_port1, 1)) ? 1 : -1; - clear_bit(ETR_FLAG_EACCES, &etr_flags); } else if (eacr.p0 && aib.esw.psc0 == etr_lpsc_operational_step) { eacr.sl = 1; eacr.e0 = 1; @@ -976,7 +1064,6 @@ static void etr_work_fn(struct work_struct *work) eacr.e1 = 1; sync_port = (etr_port0_uptodate && etr_port_valid(&etr_port0, 0)) ? 0 : -1; - clear_bit(ETR_FLAG_EACCES, &etr_flags); } else if (eacr.p1 && aib.esw.psc1 == etr_lpsc_operational_step) { eacr.sl = 1; eacr.e0 = 0; @@ -985,22 +1072,20 @@ static void etr_work_fn(struct work_struct *work) eacr.es = 0; sync_port = (etr_port1_uptodate && etr_port_valid(&etr_port1, 1)) ? 1 : -1; - clear_bit(ETR_FLAG_EACCES, &etr_flags); } else { /* Both ports not usable. */ eacr.es = eacr.sl = 0; sync_port = -1; - set_bit(ETR_FLAG_EACCES, &etr_flags); } /* * If the clock is in sync just update the eacr and return. * If there is no valid sync port wait for a port update. */ - if (eacr.es || sync_port < 0) { + if ((eacr.es && check_sync_clock()) || sync_port < 0) { etr_update_eacr(eacr); etr_set_tolec_timeout(now); - return; + goto out_unlock; } /* @@ -1013,49 +1098,56 @@ static void etr_work_fn(struct work_struct *work) /* * Update eacr and try to synchronize the clock. If the update * of eacr caused a stepping port switch (or if we have to - * assume that a stepping port switch has occured) or the + * assume that a stepping port switch has occurred) or the * clock syncing failed, reset the sync check control bit * and set up a timer to try again after 0.5 seconds */ etr_update_eacr(eacr); if (now < etr_tolec + (1600000 << 12) || - etr_sync_clock(&aib, sync_port) != 0) { + etr_sync_clock_stop(&aib, sync_port) != 0) { /* Sync failed. Try again in 1/2 second. */ eacr.es = 0; etr_update_eacr(eacr); etr_set_sync_timeout(); } else etr_set_tolec_timeout(now); +out_unlock: + mutex_unlock(&etr_work_mutex); } /* * Sysfs interface functions */ -static struct sysdev_class etr_sysclass = { - .name = "etr", +static struct bus_type etr_subsys = { + .name = "etr", + .dev_name = "etr", }; -static struct sys_device etr_port0_dev = { +static struct device etr_port0_dev = { .id = 0, - .cls = &etr_sysclass, + .bus = &etr_subsys, }; -static struct sys_device etr_port1_dev = { +static struct device etr_port1_dev = { .id = 1, - .cls = &etr_sysclass, + .bus = &etr_subsys, }; /* - * ETR class attributes + * ETR subsys attributes */ -static ssize_t etr_stepping_port_show(struct sysdev_class *class, char *buf) +static ssize_t etr_stepping_port_show(struct device *dev, + struct device_attribute *attr, + char *buf) { return sprintf(buf, "%i\n", etr_port0.esw.p); } -static SYSDEV_CLASS_ATTR(stepping_port, 0400, etr_stepping_port_show, NULL); +static DEVICE_ATTR(stepping_port, 0400, etr_stepping_port_show, NULL); -static ssize_t etr_stepping_mode_show(struct sysdev_class *class, char *buf) +static ssize_t etr_stepping_mode_show(struct device *dev, + struct device_attribute *attr, + char *buf) { char *mode_str; @@ -1068,12 +1160,12 @@ static ssize_t etr_stepping_mode_show(struct sysdev_class *class, char *buf) return sprintf(buf, "%s\n", mode_str); } -static SYSDEV_CLASS_ATTR(stepping_mode, 0400, etr_stepping_mode_show, NULL); +static DEVICE_ATTR(stepping_mode, 0400, etr_stepping_mode_show, NULL); /* * ETR port attributes */ -static inline struct etr_aib *etr_aib_from_dev(struct sys_device *dev) +static inline struct etr_aib *etr_aib_from_dev(struct device *dev) { if (dev == &etr_port0_dev) return etr_port0_online ? &etr_port0 : NULL; @@ -1081,7 +1173,9 @@ static inline struct etr_aib *etr_aib_from_dev(struct sys_device *dev) return etr_port1_online ? &etr_port1 : NULL; } -static ssize_t etr_online_show(struct sys_device *dev, char *buf) +static ssize_t etr_online_show(struct device *dev, + struct device_attribute *attr, + char *buf) { unsigned int online; @@ -1089,43 +1183,58 @@ static ssize_t etr_online_show(struct sys_device *dev, char *buf) return sprintf(buf, "%i\n", online); } -static ssize_t etr_online_store(struct sys_device *dev, - const char *buf, size_t count) +static ssize_t etr_online_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) { unsigned int value; value = simple_strtoul(buf, NULL, 0); if (value != 0 && value != 1) return -EINVAL; - if (test_bit(ETR_FLAG_ENOSYS, &etr_flags)) - return -ENOSYS; + if (!test_bit(CLOCK_SYNC_HAS_ETR, &clock_sync_flags)) + return -EOPNOTSUPP; + mutex_lock(&clock_sync_mutex); if (dev == &etr_port0_dev) { if (etr_port0_online == value) - return count; /* Nothing to do. */ + goto out; /* Nothing to do. */ etr_port0_online = value; + if (etr_port0_online && etr_port1_online) + set_bit(CLOCK_SYNC_ETR, &clock_sync_flags); + else + clear_bit(CLOCK_SYNC_ETR, &clock_sync_flags); set_bit(ETR_EVENT_PORT0_CHANGE, &etr_events); - schedule_work(&etr_work); + queue_work(time_sync_wq, &etr_work); } else { if (etr_port1_online == value) - return count; /* Nothing to do. */ + goto out; /* Nothing to do. */ etr_port1_online = value; + if (etr_port0_online && etr_port1_online) + set_bit(CLOCK_SYNC_ETR, &clock_sync_flags); + else + clear_bit(CLOCK_SYNC_ETR, &clock_sync_flags); set_bit(ETR_EVENT_PORT1_CHANGE, &etr_events); - schedule_work(&etr_work); + queue_work(time_sync_wq, &etr_work); } +out: + mutex_unlock(&clock_sync_mutex); return count; } -static SYSDEV_ATTR(online, 0600, etr_online_show, etr_online_store); +static DEVICE_ATTR(online, 0600, etr_online_show, etr_online_store); -static ssize_t etr_stepping_control_show(struct sys_device *dev, char *buf) +static ssize_t etr_stepping_control_show(struct device *dev, + struct device_attribute *attr, + char *buf) { return sprintf(buf, "%i\n", (dev == &etr_port0_dev) ? etr_eacr.e0 : etr_eacr.e1); } -static SYSDEV_ATTR(stepping_control, 0400, etr_stepping_control_show, NULL); +static DEVICE_ATTR(stepping_control, 0400, etr_stepping_control_show, NULL); -static ssize_t etr_mode_code_show(struct sys_device *dev, char *buf) +static ssize_t etr_mode_code_show(struct device *dev, + struct device_attribute *attr, char *buf) { if (!etr_port0_online && !etr_port1_online) /* Status word is not uptodate if both ports are offline. */ @@ -1134,9 +1243,10 @@ static ssize_t etr_mode_code_show(struct sys_device *dev, char *buf) etr_port0.esw.psc0 : etr_port0.esw.psc1); } -static SYSDEV_ATTR(state_code, 0400, etr_mode_code_show, NULL); +static DEVICE_ATTR(state_code, 0400, etr_mode_code_show, NULL); -static ssize_t etr_untuned_show(struct sys_device *dev, char *buf) +static ssize_t etr_untuned_show(struct device *dev, + struct device_attribute *attr, char *buf) { struct etr_aib *aib = etr_aib_from_dev(dev); @@ -1145,9 +1255,10 @@ static ssize_t etr_untuned_show(struct sys_device *dev, char *buf) return sprintf(buf, "%i\n", aib->edf1.u); } -static SYSDEV_ATTR(untuned, 0400, etr_untuned_show, NULL); +static DEVICE_ATTR(untuned, 0400, etr_untuned_show, NULL); -static ssize_t etr_network_id_show(struct sys_device *dev, char *buf) +static ssize_t etr_network_id_show(struct device *dev, + struct device_attribute *attr, char *buf) { struct etr_aib *aib = etr_aib_from_dev(dev); @@ -1156,9 +1267,10 @@ static ssize_t etr_network_id_show(struct sys_device *dev, char *buf) return sprintf(buf, "%i\n", aib->edf1.net_id); } -static SYSDEV_ATTR(network, 0400, etr_network_id_show, NULL); +static DEVICE_ATTR(network, 0400, etr_network_id_show, NULL); -static ssize_t etr_id_show(struct sys_device *dev, char *buf) +static ssize_t etr_id_show(struct device *dev, + struct device_attribute *attr, char *buf) { struct etr_aib *aib = etr_aib_from_dev(dev); @@ -1167,9 +1279,10 @@ static ssize_t etr_id_show(struct sys_device *dev, char *buf) return sprintf(buf, "%i\n", aib->edf1.etr_id); } -static SYSDEV_ATTR(id, 0400, etr_id_show, NULL); +static DEVICE_ATTR(id, 0400, etr_id_show, NULL); -static ssize_t etr_port_number_show(struct sys_device *dev, char *buf) +static ssize_t etr_port_number_show(struct device *dev, + struct device_attribute *attr, char *buf) { struct etr_aib *aib = etr_aib_from_dev(dev); @@ -1178,9 +1291,10 @@ static ssize_t etr_port_number_show(struct sys_device *dev, char *buf) return sprintf(buf, "%i\n", aib->edf1.etr_pn); } -static SYSDEV_ATTR(port, 0400, etr_port_number_show, NULL); +static DEVICE_ATTR(port, 0400, etr_port_number_show, NULL); -static ssize_t etr_coupled_show(struct sys_device *dev, char *buf) +static ssize_t etr_coupled_show(struct device *dev, + struct device_attribute *attr, char *buf) { struct etr_aib *aib = etr_aib_from_dev(dev); @@ -1189,9 +1303,10 @@ static ssize_t etr_coupled_show(struct sys_device *dev, char *buf) return sprintf(buf, "%i\n", aib->edf3.c); } -static SYSDEV_ATTR(coupled, 0400, etr_coupled_show, NULL); +static DEVICE_ATTR(coupled, 0400, etr_coupled_show, NULL); -static ssize_t etr_local_time_show(struct sys_device *dev, char *buf) +static ssize_t etr_local_time_show(struct device *dev, + struct device_attribute *attr, char *buf) { struct etr_aib *aib = etr_aib_from_dev(dev); @@ -1200,9 +1315,10 @@ static ssize_t etr_local_time_show(struct sys_device *dev, char *buf) return sprintf(buf, "%i\n", aib->edf3.blto); } -static SYSDEV_ATTR(local_time, 0400, etr_local_time_show, NULL); +static DEVICE_ATTR(local_time, 0400, etr_local_time_show, NULL); -static ssize_t etr_utc_offset_show(struct sys_device *dev, char *buf) +static ssize_t etr_utc_offset_show(struct device *dev, + struct device_attribute *attr, char *buf) { struct etr_aib *aib = etr_aib_from_dev(dev); @@ -1211,64 +1327,64 @@ static ssize_t etr_utc_offset_show(struct sys_device *dev, char *buf) return sprintf(buf, "%i\n", aib->edf3.buo); } -static SYSDEV_ATTR(utc_offset, 0400, etr_utc_offset_show, NULL); - -static struct sysdev_attribute *etr_port_attributes[] = { - &attr_online, - &attr_stepping_control, - &attr_state_code, - &attr_untuned, - &attr_network, - &attr_id, - &attr_port, - &attr_coupled, - &attr_local_time, - &attr_utc_offset, +static DEVICE_ATTR(utc_offset, 0400, etr_utc_offset_show, NULL); + +static struct device_attribute *etr_port_attributes[] = { + &dev_attr_online, + &dev_attr_stepping_control, + &dev_attr_state_code, + &dev_attr_untuned, + &dev_attr_network, + &dev_attr_id, + &dev_attr_port, + &dev_attr_coupled, + &dev_attr_local_time, + &dev_attr_utc_offset, NULL }; -static int __init etr_register_port(struct sys_device *dev) +static int __init etr_register_port(struct device *dev) { - struct sysdev_attribute **attr; + struct device_attribute **attr; int rc; - rc = sysdev_register(dev); + rc = device_register(dev); if (rc) goto out; for (attr = etr_port_attributes; *attr; attr++) { - rc = sysdev_create_file(dev, *attr); + rc = device_create_file(dev, *attr); if (rc) goto out_unreg; } return 0; out_unreg: for (; attr >= etr_port_attributes; attr--) - sysdev_remove_file(dev, *attr); - sysdev_unregister(dev); + device_remove_file(dev, *attr); + device_unregister(dev); out: return rc; } -static void __init etr_unregister_port(struct sys_device *dev) +static void __init etr_unregister_port(struct device *dev) { - struct sysdev_attribute **attr; + struct device_attribute **attr; for (attr = etr_port_attributes; *attr; attr++) - sysdev_remove_file(dev, *attr); - sysdev_unregister(dev); + device_remove_file(dev, *attr); + device_unregister(dev); } static int __init etr_init_sysfs(void) { int rc; - rc = sysdev_class_register(&etr_sysclass); + rc = subsys_system_register(&etr_subsys, NULL); if (rc) goto out; - rc = sysdev_class_create_file(&etr_sysclass, &attr_stepping_port); + rc = device_create_file(etr_subsys.dev_root, &dev_attr_stepping_port); if (rc) - goto out_unreg_class; - rc = sysdev_class_create_file(&etr_sysclass, &attr_stepping_mode); + goto out_unreg_subsys; + rc = device_create_file(etr_subsys.dev_root, &dev_attr_stepping_mode); if (rc) goto out_remove_stepping_port; rc = etr_register_port(&etr_port0_dev); @@ -1282,13 +1398,391 @@ static int __init etr_init_sysfs(void) out_remove_port0: etr_unregister_port(&etr_port0_dev); out_remove_stepping_mode: - sysdev_class_remove_file(&etr_sysclass, &attr_stepping_mode); + device_remove_file(etr_subsys.dev_root, &dev_attr_stepping_mode); out_remove_stepping_port: - sysdev_class_remove_file(&etr_sysclass, &attr_stepping_port); -out_unreg_class: - sysdev_class_unregister(&etr_sysclass); + device_remove_file(etr_subsys.dev_root, &dev_attr_stepping_port); +out_unreg_subsys: + bus_unregister(&etr_subsys); out: return rc; } device_initcall(etr_init_sysfs); + +/* + * Server Time Protocol (STP) code. + */ +static int stp_online; +static struct stp_sstpi stp_info; +static void *stp_page; + +static void stp_work_fn(struct work_struct *work); +static DEFINE_MUTEX(stp_work_mutex); +static DECLARE_WORK(stp_work, stp_work_fn); +static struct timer_list stp_timer; + +static int __init early_parse_stp(char *p) +{ + if (strncmp(p, "off", 3) == 0) + stp_online = 0; + else if (strncmp(p, "on", 2) == 0) + stp_online = 1; + return 0; +} +early_param("stp", early_parse_stp); + +/* + * Reset STP attachment. + */ +static void __init stp_reset(void) +{ + int rc; + + stp_page = (void *) get_zeroed_page(GFP_ATOMIC); + rc = chsc_sstpc(stp_page, STP_OP_CTRL, 0x0000); + if (rc == 0) + set_bit(CLOCK_SYNC_HAS_STP, &clock_sync_flags); + else if (stp_online) { + pr_warning("The real or virtual hardware system does " + "not provide an STP interface\n"); + free_page((unsigned long) stp_page); + stp_page = NULL; + stp_online = 0; + } +} + +static void stp_timeout(unsigned long dummy) +{ + queue_work(time_sync_wq, &stp_work); +} + +static int __init stp_init(void) +{ + if (!test_bit(CLOCK_SYNC_HAS_STP, &clock_sync_flags)) + return 0; + setup_timer(&stp_timer, stp_timeout, 0UL); + time_init_wq(); + if (!stp_online) + return 0; + queue_work(time_sync_wq, &stp_work); + return 0; +} + +arch_initcall(stp_init); + +/* + * STP timing alert. There are three causes: + * 1) timing status change + * 2) link availability change + * 3) time control parameter change + * In all three cases we are only interested in the clock source state. + * If a STP clock source is now available use it. + */ +static void stp_timing_alert(struct stp_irq_parm *intparm) +{ + if (intparm->tsc || intparm->lac || intparm->tcpc) + queue_work(time_sync_wq, &stp_work); +} + +/* + * STP sync check machine check. This is called when the timing state + * changes from the synchronized state to the unsynchronized state. + * After a STP sync check the clock is not in sync. The machine check + * is broadcasted to all cpus at the same time. + */ +void stp_sync_check(void) +{ + disable_sync_clock(NULL); + queue_work(time_sync_wq, &stp_work); +} + +/* + * STP island condition machine check. This is called when an attached + * server attempts to communicate over an STP link and the servers + * have matching CTN ids and have a valid stratum-1 configuration + * but the configurations do not match. + */ +void stp_island_check(void) +{ + disable_sync_clock(NULL); + queue_work(time_sync_wq, &stp_work); +} + + +static int stp_sync_clock(void *data) +{ + static int first; + unsigned long long old_clock, delta; + struct clock_sync_data *stp_sync; + int rc; + + stp_sync = data; + + if (xchg(&first, 1) == 1) { + /* Slave */ + clock_sync_cpu(stp_sync); + return 0; + } + + /* Wait until all other cpus entered the sync function. */ + while (atomic_read(&stp_sync->cpus) != 0) + cpu_relax(); + + enable_sync_clock(); + + rc = 0; + if (stp_info.todoff[0] || stp_info.todoff[1] || + stp_info.todoff[2] || stp_info.todoff[3] || + stp_info.tmd != 2) { + old_clock = get_tod_clock(); + rc = chsc_sstpc(stp_page, STP_OP_SYNC, 0); + if (rc == 0) { + delta = adjust_time(old_clock, get_tod_clock(), 0); + fixup_clock_comparator(delta); + rc = chsc_sstpi(stp_page, &stp_info, + sizeof(struct stp_sstpi)); + if (rc == 0 && stp_info.tmd != 2) + rc = -EAGAIN; + } + } + if (rc) { + disable_sync_clock(NULL); + stp_sync->in_sync = -EAGAIN; + } else + stp_sync->in_sync = 1; + xchg(&first, 0); + return 0; +} + +/* + * STP work. Check for the STP state and take over the clock + * synchronization if the STP clock source is usable. + */ +static void stp_work_fn(struct work_struct *work) +{ + struct clock_sync_data stp_sync; + int rc; + + /* prevent multiple execution. */ + mutex_lock(&stp_work_mutex); + + if (!stp_online) { + chsc_sstpc(stp_page, STP_OP_CTRL, 0x0000); + del_timer_sync(&stp_timer); + goto out_unlock; + } + + rc = chsc_sstpc(stp_page, STP_OP_CTRL, 0xb0e0); + if (rc) + goto out_unlock; + + rc = chsc_sstpi(stp_page, &stp_info, sizeof(struct stp_sstpi)); + if (rc || stp_info.c == 0) + goto out_unlock; + + /* Skip synchronization if the clock is already in sync. */ + if (check_sync_clock()) + goto out_unlock; + + memset(&stp_sync, 0, sizeof(stp_sync)); + get_online_cpus(); + atomic_set(&stp_sync.cpus, num_online_cpus() - 1); + stop_machine(stp_sync_clock, &stp_sync, cpu_online_mask); + put_online_cpus(); + + if (!check_sync_clock()) + /* + * There is a usable clock but the synchonization failed. + * Retry after a second. + */ + mod_timer(&stp_timer, jiffies + HZ); + +out_unlock: + mutex_unlock(&stp_work_mutex); +} + +/* + * STP subsys sysfs interface functions + */ +static struct bus_type stp_subsys = { + .name = "stp", + .dev_name = "stp", +}; + +static ssize_t stp_ctn_id_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + if (!stp_online) + return -ENODATA; + return sprintf(buf, "%016llx\n", + *(unsigned long long *) stp_info.ctnid); +} + +static DEVICE_ATTR(ctn_id, 0400, stp_ctn_id_show, NULL); + +static ssize_t stp_ctn_type_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + if (!stp_online) + return -ENODATA; + return sprintf(buf, "%i\n", stp_info.ctn); +} + +static DEVICE_ATTR(ctn_type, 0400, stp_ctn_type_show, NULL); + +static ssize_t stp_dst_offset_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + if (!stp_online || !(stp_info.vbits & 0x2000)) + return -ENODATA; + return sprintf(buf, "%i\n", (int)(s16) stp_info.dsto); +} + +static DEVICE_ATTR(dst_offset, 0400, stp_dst_offset_show, NULL); + +static ssize_t stp_leap_seconds_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + if (!stp_online || !(stp_info.vbits & 0x8000)) + return -ENODATA; + return sprintf(buf, "%i\n", (int)(s16) stp_info.leaps); +} + +static DEVICE_ATTR(leap_seconds, 0400, stp_leap_seconds_show, NULL); + +static ssize_t stp_stratum_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + if (!stp_online) + return -ENODATA; + return sprintf(buf, "%i\n", (int)(s16) stp_info.stratum); +} + +static DEVICE_ATTR(stratum, 0400, stp_stratum_show, NULL); + +static ssize_t stp_time_offset_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + if (!stp_online || !(stp_info.vbits & 0x0800)) + return -ENODATA; + return sprintf(buf, "%i\n", (int) stp_info.tto); +} + +static DEVICE_ATTR(time_offset, 0400, stp_time_offset_show, NULL); + +static ssize_t stp_time_zone_offset_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + if (!stp_online || !(stp_info.vbits & 0x4000)) + return -ENODATA; + return sprintf(buf, "%i\n", (int)(s16) stp_info.tzo); +} + +static DEVICE_ATTR(time_zone_offset, 0400, + stp_time_zone_offset_show, NULL); + +static ssize_t stp_timing_mode_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + if (!stp_online) + return -ENODATA; + return sprintf(buf, "%i\n", stp_info.tmd); +} + +static DEVICE_ATTR(timing_mode, 0400, stp_timing_mode_show, NULL); + +static ssize_t stp_timing_state_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + if (!stp_online) + return -ENODATA; + return sprintf(buf, "%i\n", stp_info.tst); +} + +static DEVICE_ATTR(timing_state, 0400, stp_timing_state_show, NULL); + +static ssize_t stp_online_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + return sprintf(buf, "%i\n", stp_online); +} + +static ssize_t stp_online_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + unsigned int value; + + value = simple_strtoul(buf, NULL, 0); + if (value != 0 && value != 1) + return -EINVAL; + if (!test_bit(CLOCK_SYNC_HAS_STP, &clock_sync_flags)) + return -EOPNOTSUPP; + mutex_lock(&clock_sync_mutex); + stp_online = value; + if (stp_online) + set_bit(CLOCK_SYNC_STP, &clock_sync_flags); + else + clear_bit(CLOCK_SYNC_STP, &clock_sync_flags); + queue_work(time_sync_wq, &stp_work); + mutex_unlock(&clock_sync_mutex); + return count; +} + +/* + * Can't use DEVICE_ATTR because the attribute should be named + * stp/online but dev_attr_online already exists in this file .. + */ +static struct device_attribute dev_attr_stp_online = { + .attr = { .name = "online", .mode = 0600 }, + .show = stp_online_show, + .store = stp_online_store, +}; + +static struct device_attribute *stp_attributes[] = { + &dev_attr_ctn_id, + &dev_attr_ctn_type, + &dev_attr_dst_offset, + &dev_attr_leap_seconds, + &dev_attr_stp_online, + &dev_attr_stratum, + &dev_attr_time_offset, + &dev_attr_time_zone_offset, + &dev_attr_timing_mode, + &dev_attr_timing_state, + NULL +}; + +static int __init stp_init_sysfs(void) +{ + struct device_attribute **attr; + int rc; + + rc = subsys_system_register(&stp_subsys, NULL); + if (rc) + goto out; + for (attr = stp_attributes; *attr; attr++) { + rc = device_create_file(stp_subsys.dev_root, *attr); + if (rc) + goto out_unreg; + } + return 0; +out_unreg: + for (; attr >= stp_attributes; attr--) + device_remove_file(stp_subsys.dev_root, *attr); + bus_unregister(&stp_subsys); +out: + return rc; +} + +device_initcall(stp_init_sysfs); |