diff options
author | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2008-07-14 09:58:56 +0200 |
---|---|---|
committer | Heiko Carstens <heiko.carstens@de.ibm.com> | 2008-07-14 10:02:09 +0200 |
commit | d2fec595511b5718bdb65645b3d5d99800d97943 (patch) | |
tree | a94c3560fc2ad6aa89d61d646f73f4d7c1dfcc9b /arch/s390 | |
parent | 761cdf6aacdb76f819050f4938cdab1f4cdcb945 (diff) | |
download | linux-d2fec595511b5718bdb65645b3d5d99800d97943.tar.bz2 |
[S390] stp support.
Add support for clock synchronization with the server time protocol.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Diffstat (limited to 'arch/s390')
-rw-r--r-- | arch/s390/kernel/time.c | 634 |
1 files changed, 484 insertions, 150 deletions
diff --git a/arch/s390/kernel/time.c b/arch/s390/kernel/time.c index 7aec676fefd5..7418bebb547f 100644 --- a/arch/s390/kernel/time.c +++ b/arch/s390/kernel/time.c @@ -3,7 +3,7 @@ * 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) @@ -31,6 +31,7 @@ #include <linux/notifier.h> #include <linux/clocksource.h> #include <linux/clockchips.h> +#include <linux/bootmem.h> #include <asm/uaccess.h> #include <asm/delay.h> #include <asm/s390_ext.h> @@ -162,7 +163,7 @@ 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); } @@ -170,8 +171,21 @@ static void clock_comparator_interrupt(__u16 code) { } +static void etr_timing_alert(struct etr_irq_parm *); +static void stp_timing_alert(struct stp_irq_parm *); + +static void timing_alert_interrupt(__u16 code) +{ + if (S390_lowcore.ext_params & 0x00c40000) + etr_timing_alert((struct etr_irq_parm *) + &S390_lowcore.ext_params); + if (S390_lowcore.ext_params & 0x00038000) + stp_timing_alert((struct stp_irq_parm *) + &S390_lowcore.ext_params); +} + static void etr_reset(void); -static void etr_ext_handler(__u16); +static void stp_reset(void); /* * Get the TOD clock running. @@ -181,6 +195,7 @@ static u64 __init reset_tod_clock(void) u64 time; etr_reset(); + stp_reset(); if (store_clock(&time) == 0) return time; /* TOD clock not running. Set the clock to Unix Epoch. */ @@ -231,8 +246,9 @@ void __init time_init(void) 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, + /* request the timing alert external interrupt */ + if (register_early_external_interrupt(0x1406, + timing_alert_interrupt, &ext_int_etr_cc) != 0) panic("Couldn't request external interrupt 0x1406"); @@ -245,10 +261,112 @@ void __init time_init(void) } /* + * 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); + } + 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 DEFINE_PER_CPU(atomic_t, clock_sync_word); +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 + * -ENOSYS 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_clock(); + sw1 = atomic_read(sw_ptr); + put_cpu_var(clock_sync_sync); + 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 -ENOSYS; + 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); +} + +/* * External Time Reference (ETR) code. */ 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 +391,6 @@ 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 +417,18 @@ 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 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 +437,13 @@ 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) + 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; - } + set_bit(CLOCK_SYNC_HAS_ETR, &clock_sync_flags); + } else 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; } } @@ -397,14 +451,12 @@ 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; /* 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); @@ -435,7 +487,8 @@ void etr_switch_to_local(void) { if (!etr_eacr.sl) return; - etr_disable_sync_clock(NULL); + if (test_bit(CLOCK_SYNC_ETR, &clock_sync_flags)) + disable_sync_clock(NULL); set_bit(ETR_EVENT_SWITCH_LOCAL, &etr_events); schedule_work(&etr_work); } @@ -450,23 +503,21 @@ void etr_sync_check(void) { if (!etr_eacr.es) return; - etr_disable_sync_clock(NULL); + if (test_bit(CLOCK_SYNC_ETR, &clock_sync_flags)) + disable_sync_clock(NULL); set_bit(ETR_EVENT_SYNC_CHECK, &etr_events); schedule_work(&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); @@ -591,58 +642,23 @@ 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 { int in_sync; unsigned long long fixup_cc; -} etr_sync; +}; -static void etr_sync_cpu_start(void *dummy) +static void clock_sync_cpu_start(void *dummy) { - etr_enable_sync_clock(); + struct clock_sync_data *sync = dummy; + + 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 @@ -650,17 +666,17 @@ 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); + fixup_clock_comparator(sync->fixup_cc); } -static void etr_sync_cpu_end(void *dummy) +static void clock_sync_cpu_end(void *dummy) { } @@ -672,6 +688,7 @@ static void etr_sync_cpu_end(void *dummy) static int etr_sync_clock(struct etr_aib *aib, int port) { struct etr_aib *sync_port; + struct clock_sync_data etr_sync; unsigned long long clock, old_clock, delay, delta; int follows; int rc; @@ -690,9 +707,9 @@ static int etr_sync_clock(struct etr_aib *aib, int port) */ memset(&etr_sync, 0, sizeof(etr_sync)); preempt_disable(); - smp_call_function(etr_sync_cpu_start, NULL, 0, 0); + smp_call_function(clock_sync_cpu_start, &etr_sync, 0, 0); local_irq_disable(); - etr_enable_sync_clock(); + enable_sync_clock(); /* Set clock to next OTE. */ __ctl_set_bit(14, 21); @@ -707,13 +724,13 @@ 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); + 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); + disable_sync_clock(NULL); etr_sync.in_sync = -EAGAIN; rc = -EAGAIN; } else { @@ -724,12 +741,12 @@ static int etr_sync_clock(struct etr_aib *aib, int port) /* Could not set the clock ?!? */ __ctl_clear_bit(0, 29); __ctl_clear_bit(14, 21); - etr_disable_sync_clock(NULL); + disable_sync_clock(NULL); etr_sync.in_sync = -EAGAIN; rc = -EAGAIN; } local_irq_enable(); - smp_call_function(etr_sync_cpu_end,NULL,0,0); + smp_call_function(clock_sync_cpu_end, NULL, 0, 0); preempt_enable(); return rc; } @@ -832,7 +849,7 @@ 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 (!test_bit(CLOCK_SYNC_STP, &clock_sync_flags) && !eacr.es) return eacr; /* @@ -840,7 +857,7 @@ 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; @@ -909,10 +926,10 @@ 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, 0, 1); del_timer_sync(&etr_timer); etr_update_eacr(eacr); - set_bit(ETR_FLAG_EACCES, &etr_flags); + clear_bit(CLOCK_SYNC_ETR, &clock_sync_flags); return; } @@ -953,7 +970,6 @@ 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 +978,6 @@ 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 +991,6 @@ 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; @@ -985,19 +999,22 @@ 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); + clear_bit(CLOCK_SYNC_ETR, &clock_sync_flags); } + if (!test_bit(CLOCK_SYNC_ETR, &clock_sync_flags)) + eacr.es = 0; + /* * 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 (test_bit(CLOCK_SYNC_STP, &clock_sync_flags) || + eacr.es || sync_port < 0) { etr_update_eacr(eacr); etr_set_tolec_timeout(now); return; @@ -1018,11 +1035,13 @@ static void etr_work_fn(struct work_struct *work) * and set up a timer to try again after 0.5 seconds */ etr_update_eacr(eacr); + set_bit(CLOCK_SYNC_ETR, &clock_sync_flags); if (now < etr_tolec + (1600000 << 12) || etr_sync_clock(&aib, sync_port) != 0) { /* Sync failed. Try again in 1/2 second. */ eacr.es = 0; etr_update_eacr(eacr); + clear_bit(CLOCK_SYNC_ETR, &clock_sync_flags); etr_set_sync_timeout(); } else etr_set_tolec_timeout(now); @@ -1097,8 +1116,8 @@ static ssize_t etr_online_store(struct sys_device *dev, 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; if (dev == &etr_port0_dev) { if (etr_port0_online == value) return count; /* Nothing to do. */ @@ -1292,3 +1311,318 @@ out: } 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 DECLARE_WORK(stp_work, stp_work_fn); + +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 stp_reset(void) +{ + int rc; + + stp_page = alloc_bootmem_pages(PAGE_SIZE); + rc = chsc_sstpc(stp_page, STP_OP_CTRL, 0x0000); + if (rc == 1) + set_bit(CLOCK_SYNC_HAS_STP, &clock_sync_flags); + else if (stp_online) { + printk(KERN_WARNING "Running on non STP capable machine.\n"); + free_bootmem((unsigned long) stp_page, PAGE_SIZE); + stp_page = NULL; + stp_online = 0; + } +} + +static int __init stp_init(void) +{ + if (test_bit(CLOCK_SYNC_HAS_STP, &clock_sync_flags) && stp_online) + schedule_work(&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) + schedule_work(&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) +{ + if (!test_bit(CLOCK_SYNC_STP, &clock_sync_flags)) + return; + disable_sync_clock(NULL); + schedule_work(&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) +{ + if (!test_bit(CLOCK_SYNC_STP, &clock_sync_flags)) + return; + disable_sync_clock(NULL); + schedule_work(&stp_work); +} + +/* + * STP tasklet. 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; + unsigned long long old_clock, delta; + int rc; + + if (!stp_online) { + chsc_sstpc(stp_page, STP_OP_CTRL, 0x0000); + return; + } + + rc = chsc_sstpc(stp_page, STP_OP_CTRL, 0xb0e0); + if (rc) + return; + + rc = chsc_sstpi(stp_page, &stp_info, sizeof(struct stp_sstpi)); + if (rc || stp_info.c == 0) + return; + + /* + * 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 clock_sync_cpu_start. + */ + memset(&stp_sync, 0, sizeof(stp_sync)); + preempt_disable(); + smp_call_function(clock_sync_cpu_start, &stp_sync, 0, 0); + local_irq_disable(); + enable_sync_clock(); + + set_bit(CLOCK_SYNC_STP, &clock_sync_flags); + if (test_and_clear_bit(CLOCK_SYNC_ETR, &clock_sync_flags)) + schedule_work(&etr_work); + + 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_clock(); + rc = chsc_sstpc(stp_page, STP_OP_SYNC, 0); + if (rc == 0) { + delta = adjust_time(old_clock, get_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; + clear_bit(CLOCK_SYNC_STP, &clock_sync_flags); + if (etr_port0_online || etr_port1_online) + schedule_work(&etr_work); + } else + stp_sync.in_sync = 1; + + local_irq_enable(); + smp_call_function(clock_sync_cpu_end, NULL, 0, 0); + preempt_enable(); +} + +/* + * STP class sysfs interface functions + */ +static struct sysdev_class stp_sysclass = { + .name = "stp", +}; + +static ssize_t stp_ctn_id_show(struct sysdev_class *class, char *buf) +{ + if (!stp_online) + return -ENODATA; + return sprintf(buf, "%016llx\n", + *(unsigned long long *) stp_info.ctnid); +} + +static SYSDEV_CLASS_ATTR(ctn_id, 0400, stp_ctn_id_show, NULL); + +static ssize_t stp_ctn_type_show(struct sysdev_class *class, char *buf) +{ + if (!stp_online) + return -ENODATA; + return sprintf(buf, "%i\n", stp_info.ctn); +} + +static SYSDEV_CLASS_ATTR(ctn_type, 0400, stp_ctn_type_show, NULL); + +static ssize_t stp_dst_offset_show(struct sysdev_class *class, char *buf) +{ + if (!stp_online || !(stp_info.vbits & 0x2000)) + return -ENODATA; + return sprintf(buf, "%i\n", (int)(s16) stp_info.dsto); +} + +static SYSDEV_CLASS_ATTR(dst_offset, 0400, stp_dst_offset_show, NULL); + +static ssize_t stp_leap_seconds_show(struct sysdev_class *class, char *buf) +{ + if (!stp_online || !(stp_info.vbits & 0x8000)) + return -ENODATA; + return sprintf(buf, "%i\n", (int)(s16) stp_info.leaps); +} + +static SYSDEV_CLASS_ATTR(leap_seconds, 0400, stp_leap_seconds_show, NULL); + +static ssize_t stp_stratum_show(struct sysdev_class *class, char *buf) +{ + if (!stp_online) + return -ENODATA; + return sprintf(buf, "%i\n", (int)(s16) stp_info.stratum); +} + +static SYSDEV_CLASS_ATTR(stratum, 0400, stp_stratum_show, NULL); + +static ssize_t stp_time_offset_show(struct sysdev_class *class, char *buf) +{ + if (!stp_online || !(stp_info.vbits & 0x0800)) + return -ENODATA; + return sprintf(buf, "%i\n", (int) stp_info.tto); +} + +static SYSDEV_CLASS_ATTR(time_offset, 0400, stp_time_offset_show, NULL); + +static ssize_t stp_time_zone_offset_show(struct sysdev_class *class, char *buf) +{ + if (!stp_online || !(stp_info.vbits & 0x4000)) + return -ENODATA; + return sprintf(buf, "%i\n", (int)(s16) stp_info.tzo); +} + +static SYSDEV_CLASS_ATTR(time_zone_offset, 0400, + stp_time_zone_offset_show, NULL); + +static ssize_t stp_timing_mode_show(struct sysdev_class *class, char *buf) +{ + if (!stp_online) + return -ENODATA; + return sprintf(buf, "%i\n", stp_info.tmd); +} + +static SYSDEV_CLASS_ATTR(timing_mode, 0400, stp_timing_mode_show, NULL); + +static ssize_t stp_timing_state_show(struct sysdev_class *class, char *buf) +{ + if (!stp_online) + return -ENODATA; + return sprintf(buf, "%i\n", stp_info.tst); +} + +static SYSDEV_CLASS_ATTR(timing_state, 0400, stp_timing_state_show, NULL); + +static ssize_t stp_online_show(struct sysdev_class *class, char *buf) +{ + return sprintf(buf, "%i\n", stp_online); +} + +static ssize_t stp_online_store(struct sysdev_class *class, + 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; + stp_online = value; + schedule_work(&stp_work); + return count; +} + +/* + * Can't use SYSDEV_CLASS_ATTR because the attribute should be named + * stp/online but attr_online already exists in this file .. + */ +static struct sysdev_class_attribute attr_stp_online = { + .attr = { .name = "online", .mode = 0600 }, + .show = stp_online_show, + .store = stp_online_store, +}; + +static struct sysdev_class_attribute *stp_attributes[] = { + &attr_ctn_id, + &attr_ctn_type, + &attr_dst_offset, + &attr_leap_seconds, + &attr_stp_online, + &attr_stratum, + &attr_time_offset, + &attr_time_zone_offset, + &attr_timing_mode, + &attr_timing_state, + NULL +}; + +static int __init stp_init_sysfs(void) +{ + struct sysdev_class_attribute **attr; + int rc; + + rc = sysdev_class_register(&stp_sysclass); + if (rc) + goto out; + for (attr = stp_attributes; *attr; attr++) { + rc = sysdev_class_create_file(&stp_sysclass, *attr); + if (rc) + goto out_unreg; + } + return 0; +out_unreg: + for (; attr >= stp_attributes; attr--) + sysdev_class_remove_file(&stp_sysclass, *attr); + sysdev_class_unregister(&stp_sysclass); +out: + return rc; +} + +device_initcall(stp_init_sysfs); |