2 * arch/s390/kernel/time.c
3 * Time of day based timer functions.
6 * Copyright IBM Corp. 1999, 2008
7 * Author(s): Hartmut Penner (hp@de.ibm.com),
8 * Martin Schwidefsky (schwidefsky@de.ibm.com),
9 * Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com)
11 * Derived from "arch/i386/kernel/time.c"
12 * Copyright (C) 1991, 1992, 1995 Linus Torvalds
15 #define KMSG_COMPONENT "time"
16 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
18 #include <linux/errno.h>
19 #include <linux/module.h>
20 #include <linux/sched.h>
21 #include <linux/kernel.h>
22 #include <linux/param.h>
23 #include <linux/string.h>
25 #include <linux/interrupt.h>
26 #include <linux/cpu.h>
27 #include <linux/stop_machine.h>
28 #include <linux/time.h>
29 #include <linux/sysdev.h>
30 #include <linux/delay.h>
31 #include <linux/init.h>
32 #include <linux/smp.h>
33 #include <linux/types.h>
34 #include <linux/profile.h>
35 #include <linux/timex.h>
36 #include <linux/notifier.h>
37 #include <linux/clocksource.h>
38 #include <linux/clockchips.h>
39 #include <linux/gfp.h>
40 #include <asm/uaccess.h>
41 #include <asm/delay.h>
42 #include <asm/s390_ext.h>
43 #include <asm/div64.h>
46 #include <asm/irq_regs.h>
47 #include <asm/timer.h>
51 /* change this if you have some constant time drift */
52 #define USECS_PER_JIFFY ((unsigned long) 1000000/HZ)
53 #define CLK_TICKS_PER_JIFFY ((unsigned long) USECS_PER_JIFFY << 12)
55 u64 sched_clock_base_cc
= -1; /* Force to data section. */
56 EXPORT_SYMBOL_GPL(sched_clock_base_cc
);
58 static DEFINE_PER_CPU(struct clock_event_device
, comparators
);
61 * Scheduler clock - returns current time in nanosec units.
63 unsigned long long notrace
sched_clock(void)
65 return (get_clock_monotonic() * 125) >> 9;
69 * Monotonic_clock - returns # of nanoseconds passed since time_init()
71 unsigned long long monotonic_clock(void)
75 EXPORT_SYMBOL(monotonic_clock
);
77 void tod_to_timeval(__u64 todval
, struct timespec
*xt
)
79 unsigned long long sec
;
84 todval
-= (sec
* 1000000) << 12;
85 xt
->tv_nsec
= ((todval
* 1000) >> 12);
87 EXPORT_SYMBOL(tod_to_timeval
);
89 void clock_comparator_work(void)
91 struct clock_event_device
*cd
;
93 S390_lowcore
.clock_comparator
= -1ULL;
94 set_clock_comparator(S390_lowcore
.clock_comparator
);
95 cd
= &__get_cpu_var(comparators
);
96 cd
->event_handler(cd
);
100 * Fixup the clock comparator.
102 static void fixup_clock_comparator(unsigned long long delta
)
104 /* If nobody is waiting there's nothing to fix. */
105 if (S390_lowcore
.clock_comparator
== -1ULL)
107 S390_lowcore
.clock_comparator
+= delta
;
108 set_clock_comparator(S390_lowcore
.clock_comparator
);
111 static int s390_next_event(unsigned long delta
,
112 struct clock_event_device
*evt
)
114 S390_lowcore
.clock_comparator
= get_clock() + delta
;
115 set_clock_comparator(S390_lowcore
.clock_comparator
);
119 static void s390_set_mode(enum clock_event_mode mode
,
120 struct clock_event_device
*evt
)
125 * Set up lowcore and control register of the current cpu to
126 * enable TOD clock and clock comparator interrupts.
128 void init_cpu_timer(void)
130 struct clock_event_device
*cd
;
133 S390_lowcore
.clock_comparator
= -1ULL;
134 set_clock_comparator(S390_lowcore
.clock_comparator
);
136 cpu
= smp_processor_id();
137 cd
= &per_cpu(comparators
, cpu
);
138 cd
->name
= "comparator";
139 cd
->features
= CLOCK_EVT_FEAT_ONESHOT
;
142 cd
->min_delta_ns
= 1;
143 cd
->max_delta_ns
= LONG_MAX
;
145 cd
->cpumask
= cpumask_of(cpu
);
146 cd
->set_next_event
= s390_next_event
;
147 cd
->set_mode
= s390_set_mode
;
149 clockevents_register_device(cd
);
151 /* Enable clock comparator timer interrupt. */
154 /* Always allow the timing alert external interrupt. */
158 static void clock_comparator_interrupt(__u16 code
)
160 if (S390_lowcore
.clock_comparator
== -1ULL)
161 set_clock_comparator(S390_lowcore
.clock_comparator
);
164 static void etr_timing_alert(struct etr_irq_parm
*);
165 static void stp_timing_alert(struct stp_irq_parm
*);
167 static void timing_alert_interrupt(__u16 code
)
169 if (S390_lowcore
.ext_params
& 0x00c40000)
170 etr_timing_alert((struct etr_irq_parm
*)
171 &S390_lowcore
.ext_params
);
172 if (S390_lowcore
.ext_params
& 0x00038000)
173 stp_timing_alert((struct stp_irq_parm
*)
174 &S390_lowcore
.ext_params
);
177 static void etr_reset(void);
178 static void stp_reset(void);
180 void read_persistent_clock(struct timespec
*ts
)
182 tod_to_timeval(get_clock() - TOD_UNIX_EPOCH
, ts
);
185 void read_boot_clock(struct timespec
*ts
)
187 tod_to_timeval(sched_clock_base_cc
- TOD_UNIX_EPOCH
, ts
);
190 static cycle_t
read_tod_clock(struct clocksource
*cs
)
195 static struct clocksource clocksource_tod
= {
198 .read
= read_tod_clock
,
202 .flags
= CLOCK_SOURCE_IS_CONTINUOUS
,
205 struct clocksource
* __init
clocksource_default_clock(void)
207 return &clocksource_tod
;
210 void update_vsyscall(struct timespec
*wall_time
, struct clocksource
*clock
,
213 if (clock
!= &clocksource_tod
)
216 /* Make userspace gettimeofday spin until we're done. */
217 ++vdso_data
->tb_update_count
;
219 vdso_data
->xtime_tod_stamp
= clock
->cycle_last
;
220 vdso_data
->xtime_clock_sec
= wall_time
->tv_sec
;
221 vdso_data
->xtime_clock_nsec
= wall_time
->tv_nsec
;
222 vdso_data
->wtom_clock_sec
= wall_to_monotonic
.tv_sec
;
223 vdso_data
->wtom_clock_nsec
= wall_to_monotonic
.tv_nsec
;
225 ++vdso_data
->tb_update_count
;
228 extern struct timezone sys_tz
;
230 void update_vsyscall_tz(void)
232 /* Make userspace gettimeofday spin until we're done. */
233 ++vdso_data
->tb_update_count
;
235 vdso_data
->tz_minuteswest
= sys_tz
.tz_minuteswest
;
236 vdso_data
->tz_dsttime
= sys_tz
.tz_dsttime
;
238 ++vdso_data
->tb_update_count
;
242 * Initialize the TOD clock and the CPU timer of
245 void __init
time_init(void)
247 /* Reset time synchronization interfaces. */
251 /* request the clock comparator external interrupt */
252 if (register_external_interrupt(0x1004, clock_comparator_interrupt
))
253 panic("Couldn't request external interrupt 0x1004");
255 /* request the timing alert external interrupt */
256 if (register_external_interrupt(0x1406, timing_alert_interrupt
))
257 panic("Couldn't request external interrupt 0x1406");
259 if (clocksource_register(&clocksource_tod
) != 0)
260 panic("Could not register TOD clock source");
262 /* Enable TOD clock interrupts on the boot cpu. */
265 /* Enable cpu timer interrupts on the boot cpu. */
270 * The time is "clock". old is what we think the time is.
271 * Adjust the value by a multiple of jiffies and add the delta to ntp.
272 * "delay" is an approximation how long the synchronization took. If
273 * the time correction is positive, then "delay" is subtracted from
274 * the time difference and only the remaining part is passed to ntp.
276 static unsigned long long adjust_time(unsigned long long old
,
277 unsigned long long clock
,
278 unsigned long long delay
)
280 unsigned long long delta
, ticks
;
284 /* It is later than we thought. */
285 delta
= ticks
= clock
- old
;
286 delta
= ticks
= (delta
< delay
) ? 0 : delta
- delay
;
287 delta
-= do_div(ticks
, CLK_TICKS_PER_JIFFY
);
288 adjust
.offset
= ticks
* (1000000 / HZ
);
290 /* It is earlier than we thought. */
291 delta
= ticks
= old
- clock
;
292 delta
-= do_div(ticks
, CLK_TICKS_PER_JIFFY
);
294 adjust
.offset
= -ticks
* (1000000 / HZ
);
296 sched_clock_base_cc
+= delta
;
297 if (adjust
.offset
!= 0) {
298 pr_notice("The ETR interface has adjusted the clock "
299 "by %li microseconds\n", adjust
.offset
);
300 adjust
.modes
= ADJ_OFFSET_SINGLESHOT
;
301 do_adjtimex(&adjust
);
306 static DEFINE_PER_CPU(atomic_t
, clock_sync_word
);
307 static DEFINE_MUTEX(clock_sync_mutex
);
308 static unsigned long clock_sync_flags
;
310 #define CLOCK_SYNC_HAS_ETR 0
311 #define CLOCK_SYNC_HAS_STP 1
312 #define CLOCK_SYNC_ETR 2
313 #define CLOCK_SYNC_STP 3
316 * The synchronous get_clock function. It will write the current clock
317 * value to the clock pointer and return 0 if the clock is in sync with
318 * the external time source. If the clock mode is local it will return
319 * -ENOSYS and -EAGAIN if the clock is not in sync with the external
322 int get_sync_clock(unsigned long long *clock
)
325 unsigned int sw0
, sw1
;
327 sw_ptr
= &get_cpu_var(clock_sync_word
);
328 sw0
= atomic_read(sw_ptr
);
329 *clock
= get_clock();
330 sw1
= atomic_read(sw_ptr
);
331 put_cpu_var(clock_sync_word
);
332 if (sw0
== sw1
&& (sw0
& 0x80000000U
))
333 /* Success: time is in sync. */
335 if (!test_bit(CLOCK_SYNC_HAS_ETR
, &clock_sync_flags
) &&
336 !test_bit(CLOCK_SYNC_HAS_STP
, &clock_sync_flags
))
338 if (!test_bit(CLOCK_SYNC_ETR
, &clock_sync_flags
) &&
339 !test_bit(CLOCK_SYNC_STP
, &clock_sync_flags
))
343 EXPORT_SYMBOL(get_sync_clock
);
346 * Make get_sync_clock return -EAGAIN.
348 static void disable_sync_clock(void *dummy
)
350 atomic_t
*sw_ptr
= &__get_cpu_var(clock_sync_word
);
352 * Clear the in-sync bit 2^31. All get_sync_clock calls will
353 * fail until the sync bit is turned back on. In addition
354 * increase the "sequence" counter to avoid the race of an
355 * etr event and the complete recovery against get_sync_clock.
357 atomic_clear_mask(0x80000000, sw_ptr
);
362 * Make get_sync_clock return 0 again.
363 * Needs to be called from a context disabled for preemption.
365 static void enable_sync_clock(void)
367 atomic_t
*sw_ptr
= &__get_cpu_var(clock_sync_word
);
368 atomic_set_mask(0x80000000, sw_ptr
);
372 * Function to check if the clock is in sync.
374 static inline int check_sync_clock(void)
379 sw_ptr
= &get_cpu_var(clock_sync_word
);
380 rc
= (atomic_read(sw_ptr
) & 0x80000000U
) != 0;
381 put_cpu_var(clock_sync_word
);
385 /* Single threaded workqueue used for etr and stp sync events */
386 static struct workqueue_struct
*time_sync_wq
;
388 static void __init
time_init_wq(void)
392 time_sync_wq
= create_singlethread_workqueue("timesync");
393 stop_machine_create();
397 * External Time Reference (ETR) code.
399 static int etr_port0_online
;
400 static int etr_port1_online
;
401 static int etr_steai_available
;
403 static int __init
early_parse_etr(char *p
)
405 if (strncmp(p
, "off", 3) == 0)
406 etr_port0_online
= etr_port1_online
= 0;
407 else if (strncmp(p
, "port0", 5) == 0)
408 etr_port0_online
= 1;
409 else if (strncmp(p
, "port1", 5) == 0)
410 etr_port1_online
= 1;
411 else if (strncmp(p
, "on", 2) == 0)
412 etr_port0_online
= etr_port1_online
= 1;
415 early_param("etr", early_parse_etr
);
418 ETR_EVENT_PORT0_CHANGE
,
419 ETR_EVENT_PORT1_CHANGE
,
420 ETR_EVENT_PORT_ALERT
,
421 ETR_EVENT_SYNC_CHECK
,
422 ETR_EVENT_SWITCH_LOCAL
,
427 * Valid bit combinations of the eacr register are (x = don't care):
428 * e0 e1 dp p0 p1 ea es sl
429 * 0 0 x 0 0 0 0 0 initial, disabled state
430 * 0 0 x 0 1 1 0 0 port 1 online
431 * 0 0 x 1 0 1 0 0 port 0 online
432 * 0 0 x 1 1 1 0 0 both ports online
433 * 0 1 x 0 1 1 0 0 port 1 online and usable, ETR or PPS mode
434 * 0 1 x 0 1 1 0 1 port 1 online, usable and ETR mode
435 * 0 1 x 0 1 1 1 0 port 1 online, usable, PPS mode, in-sync
436 * 0 1 x 0 1 1 1 1 port 1 online, usable, ETR mode, in-sync
437 * 0 1 x 1 1 1 0 0 both ports online, port 1 usable
438 * 0 1 x 1 1 1 1 0 both ports online, port 1 usable, PPS mode, in-sync
439 * 0 1 x 1 1 1 1 1 both ports online, port 1 usable, ETR mode, in-sync
440 * 1 0 x 1 0 1 0 0 port 0 online and usable, ETR or PPS mode
441 * 1 0 x 1 0 1 0 1 port 0 online, usable and ETR mode
442 * 1 0 x 1 0 1 1 0 port 0 online, usable, PPS mode, in-sync
443 * 1 0 x 1 0 1 1 1 port 0 online, usable, ETR mode, in-sync
444 * 1 0 x 1 1 1 0 0 both ports online, port 0 usable
445 * 1 0 x 1 1 1 1 0 both ports online, port 0 usable, PPS mode, in-sync
446 * 1 0 x 1 1 1 1 1 both ports online, port 0 usable, ETR mode, in-sync
447 * 1 1 x 1 1 1 1 0 both ports online & usable, ETR, in-sync
448 * 1 1 x 1 1 1 1 1 both ports online & usable, ETR, in-sync
450 static struct etr_eacr etr_eacr
;
451 static u64 etr_tolec
; /* time of last eacr update */
452 static struct etr_aib etr_port0
;
453 static int etr_port0_uptodate
;
454 static struct etr_aib etr_port1
;
455 static int etr_port1_uptodate
;
456 static unsigned long etr_events
;
457 static struct timer_list etr_timer
;
459 static void etr_timeout(unsigned long dummy
);
460 static void etr_work_fn(struct work_struct
*work
);
461 static DEFINE_MUTEX(etr_work_mutex
);
462 static DECLARE_WORK(etr_work
, etr_work_fn
);
465 * Reset ETR attachment.
467 static void etr_reset(void)
469 etr_eacr
= (struct etr_eacr
) {
470 .e0
= 0, .e1
= 0, ._pad0
= 4, .dp
= 0,
471 .p0
= 0, .p1
= 0, ._pad1
= 0, .ea
= 0,
473 if (etr_setr(&etr_eacr
) == 0) {
474 etr_tolec
= get_clock();
475 set_bit(CLOCK_SYNC_HAS_ETR
, &clock_sync_flags
);
476 if (etr_port0_online
&& etr_port1_online
)
477 set_bit(CLOCK_SYNC_ETR
, &clock_sync_flags
);
478 } else if (etr_port0_online
|| etr_port1_online
) {
479 pr_warning("The real or virtual hardware system does "
480 "not provide an ETR interface\n");
481 etr_port0_online
= etr_port1_online
= 0;
485 static int __init
etr_init(void)
489 if (!test_bit(CLOCK_SYNC_HAS_ETR
, &clock_sync_flags
))
492 /* Check if this machine has the steai instruction. */
493 if (etr_steai(&aib
, ETR_STEAI_STEPPING_PORT
) == 0)
494 etr_steai_available
= 1;
495 setup_timer(&etr_timer
, etr_timeout
, 0UL);
496 if (etr_port0_online
) {
497 set_bit(ETR_EVENT_PORT0_CHANGE
, &etr_events
);
498 queue_work(time_sync_wq
, &etr_work
);
500 if (etr_port1_online
) {
501 set_bit(ETR_EVENT_PORT1_CHANGE
, &etr_events
);
502 queue_work(time_sync_wq
, &etr_work
);
507 arch_initcall(etr_init
);
510 * Two sorts of ETR machine checks. The architecture reads:
511 * "When a machine-check niterruption occurs and if a switch-to-local or
512 * ETR-sync-check interrupt request is pending but disabled, this pending
513 * disabled interruption request is indicated and is cleared".
514 * Which means that we can get etr_switch_to_local events from the machine
515 * check handler although the interruption condition is disabled. Lovely..
519 * Switch to local machine check. This is called when the last usable
520 * ETR port goes inactive. After switch to local the clock is not in sync.
522 void etr_switch_to_local(void)
526 disable_sync_clock(NULL
);
527 set_bit(ETR_EVENT_SWITCH_LOCAL
, &etr_events
);
528 queue_work(time_sync_wq
, &etr_work
);
532 * ETR sync check machine check. This is called when the ETR OTE and the
533 * local clock OTE are farther apart than the ETR sync check tolerance.
534 * After a ETR sync check the clock is not in sync. The machine check
535 * is broadcasted to all cpus at the same time.
537 void etr_sync_check(void)
541 disable_sync_clock(NULL
);
542 set_bit(ETR_EVENT_SYNC_CHECK
, &etr_events
);
543 queue_work(time_sync_wq
, &etr_work
);
547 * ETR timing alert. There are two causes:
548 * 1) port state change, check the usability of the port
549 * 2) port alert, one of the ETR-data-validity bits (v1-v2 bits of the
550 * sldr-status word) or ETR-data word 1 (edf1) or ETR-data word 3 (edf3)
551 * or ETR-data word 4 (edf4) has changed.
553 static void etr_timing_alert(struct etr_irq_parm
*intparm
)
556 /* ETR port 0 state change. */
557 set_bit(ETR_EVENT_PORT0_CHANGE
, &etr_events
);
559 /* ETR port 1 state change. */
560 set_bit(ETR_EVENT_PORT1_CHANGE
, &etr_events
);
563 * ETR port alert on either port 0, 1 or both.
564 * Both ports are not up-to-date now.
566 set_bit(ETR_EVENT_PORT_ALERT
, &etr_events
);
567 queue_work(time_sync_wq
, &etr_work
);
570 static void etr_timeout(unsigned long dummy
)
572 set_bit(ETR_EVENT_UPDATE
, &etr_events
);
573 queue_work(time_sync_wq
, &etr_work
);
577 * Check if the etr mode is pss.
579 static inline int etr_mode_is_pps(struct etr_eacr eacr
)
581 return eacr
.es
&& !eacr
.sl
;
585 * Check if the etr mode is etr.
587 static inline int etr_mode_is_etr(struct etr_eacr eacr
)
589 return eacr
.es
&& eacr
.sl
;
593 * Check if the port can be used for TOD synchronization.
594 * For PPS mode the port has to receive OTEs. For ETR mode
595 * the port has to receive OTEs, the ETR stepping bit has to
596 * be zero and the validity bits for data frame 1, 2, and 3
599 static int etr_port_valid(struct etr_aib
*aib
, int port
)
603 /* Check that this port is receiving OTEs. */
607 psc
= port
? aib
->esw
.psc1
: aib
->esw
.psc0
;
608 if (psc
== etr_lpsc_pps_mode
)
610 if (psc
== etr_lpsc_operational_step
)
611 return !aib
->esw
.y
&& aib
->slsw
.v1
&&
612 aib
->slsw
.v2
&& aib
->slsw
.v3
;
617 * Check if two ports are on the same network.
619 static int etr_compare_network(struct etr_aib
*aib1
, struct etr_aib
*aib2
)
621 // FIXME: any other fields we have to compare?
622 return aib1
->edf1
.net_id
== aib2
->edf1
.net_id
;
626 * Wrapper for etr_stei that converts physical port states
627 * to logical port states to be consistent with the output
628 * of stetr (see etr_psc vs. etr_lpsc).
630 static void etr_steai_cv(struct etr_aib
*aib
, unsigned int func
)
632 BUG_ON(etr_steai(aib
, func
) != 0);
633 /* Convert port state to logical port state. */
634 if (aib
->esw
.psc0
== 1)
636 else if (aib
->esw
.psc0
== 0 && aib
->esw
.p
== 0)
638 if (aib
->esw
.psc1
== 1)
640 else if (aib
->esw
.psc1
== 0 && aib
->esw
.p
== 1)
645 * Check if the aib a2 is still connected to the same attachment as
646 * aib a1, the etv values differ by one and a2 is valid.
648 static int etr_aib_follows(struct etr_aib
*a1
, struct etr_aib
*a2
, int p
)
650 int state_a1
, state_a2
;
652 /* Paranoia check: e0/e1 should better be the same. */
653 if (a1
->esw
.eacr
.e0
!= a2
->esw
.eacr
.e0
||
654 a1
->esw
.eacr
.e1
!= a2
->esw
.eacr
.e1
)
657 /* Still connected to the same etr ? */
658 state_a1
= p
? a1
->esw
.psc1
: a1
->esw
.psc0
;
659 state_a2
= p
? a2
->esw
.psc1
: a2
->esw
.psc0
;
660 if (state_a1
== etr_lpsc_operational_step
) {
661 if (state_a2
!= etr_lpsc_operational_step
||
662 a1
->edf1
.net_id
!= a2
->edf1
.net_id
||
663 a1
->edf1
.etr_id
!= a2
->edf1
.etr_id
||
664 a1
->edf1
.etr_pn
!= a2
->edf1
.etr_pn
)
666 } else if (state_a2
!= etr_lpsc_pps_mode
)
669 /* The ETV value of a2 needs to be ETV of a1 + 1. */
670 if (a1
->edf2
.etv
+ 1 != a2
->edf2
.etv
)
673 if (!etr_port_valid(a2
, p
))
679 struct clock_sync_data
{
682 unsigned long long fixup_cc
;
684 struct etr_aib
*etr_aib
;
687 static void clock_sync_cpu(struct clock_sync_data
*sync
)
689 atomic_dec(&sync
->cpus
);
692 * This looks like a busy wait loop but it isn't. etr_sync_cpus
693 * is called on all other cpus while the TOD clocks is stopped.
694 * __udelay will stop the cpu on an enabled wait psw until the
695 * TOD is running again.
697 while (sync
->in_sync
== 0) {
700 * A different cpu changes *in_sync. Therefore use
701 * barrier() to force memory access.
705 if (sync
->in_sync
!= 1)
706 /* Didn't work. Clear per-cpu in sync bit again. */
707 disable_sync_clock(NULL
);
709 * This round of TOD syncing is done. Set the clock comparator
710 * to the next tick and let the processor continue.
712 fixup_clock_comparator(sync
->fixup_cc
);
716 * Sync the TOD clock using the port refered to by aibp. This port
717 * has to be enabled and the other port has to be disabled. The
718 * last eacr update has to be more than 1.6 seconds in the past.
720 static int etr_sync_clock(void *data
)
723 unsigned long long clock
, old_clock
, delay
, delta
;
724 struct clock_sync_data
*etr_sync
;
725 struct etr_aib
*sync_port
, *aib
;
731 if (xchg(&first
, 1) == 1) {
733 clock_sync_cpu(etr_sync
);
737 /* Wait until all other cpus entered the sync function. */
738 while (atomic_read(&etr_sync
->cpus
) != 0)
741 port
= etr_sync
->etr_port
;
742 aib
= etr_sync
->etr_aib
;
743 sync_port
= (port
== 0) ? &etr_port0
: &etr_port1
;
746 /* Set clock to next OTE. */
747 __ctl_set_bit(14, 21);
748 __ctl_set_bit(0, 29);
749 clock
= ((unsigned long long) (aib
->edf2
.etv
+ 1)) << 32;
750 old_clock
= get_clock();
751 if (set_clock(clock
) == 0) {
752 __udelay(1); /* Wait for the clock to start. */
753 __ctl_clear_bit(0, 29);
754 __ctl_clear_bit(14, 21);
756 /* Adjust Linux timing variables. */
757 delay
= (unsigned long long)
758 (aib
->edf2
.etv
- sync_port
->edf2
.etv
) << 32;
759 delta
= adjust_time(old_clock
, clock
, delay
);
760 etr_sync
->fixup_cc
= delta
;
761 fixup_clock_comparator(delta
);
762 /* Verify that the clock is properly set. */
763 if (!etr_aib_follows(sync_port
, aib
, port
)) {
765 disable_sync_clock(NULL
);
766 etr_sync
->in_sync
= -EAGAIN
;
769 etr_sync
->in_sync
= 1;
773 /* Could not set the clock ?!? */
774 __ctl_clear_bit(0, 29);
775 __ctl_clear_bit(14, 21);
776 disable_sync_clock(NULL
);
777 etr_sync
->in_sync
= -EAGAIN
;
784 static int etr_sync_clock_stop(struct etr_aib
*aib
, int port
)
786 struct clock_sync_data etr_sync
;
787 struct etr_aib
*sync_port
;
791 /* Check if the current aib is adjacent to the sync port aib. */
792 sync_port
= (port
== 0) ? &etr_port0
: &etr_port1
;
793 follows
= etr_aib_follows(sync_port
, aib
, port
);
794 memcpy(sync_port
, aib
, sizeof(*aib
));
797 memset(&etr_sync
, 0, sizeof(etr_sync
));
798 etr_sync
.etr_aib
= aib
;
799 etr_sync
.etr_port
= port
;
801 atomic_set(&etr_sync
.cpus
, num_online_cpus() - 1);
802 rc
= stop_machine(etr_sync_clock
, &etr_sync
, &cpu_online_map
);
808 * Handle the immediate effects of the different events.
809 * The port change event is used for online/offline changes.
811 static struct etr_eacr
etr_handle_events(struct etr_eacr eacr
)
813 if (test_and_clear_bit(ETR_EVENT_SYNC_CHECK
, &etr_events
))
815 if (test_and_clear_bit(ETR_EVENT_SWITCH_LOCAL
, &etr_events
))
816 eacr
.es
= eacr
.sl
= 0;
817 if (test_and_clear_bit(ETR_EVENT_PORT_ALERT
, &etr_events
))
818 etr_port0_uptodate
= etr_port1_uptodate
= 0;
820 if (test_and_clear_bit(ETR_EVENT_PORT0_CHANGE
, &etr_events
)) {
823 * Port change of an enabled port. We have to
824 * assume that this can have caused an stepping
827 etr_tolec
= get_clock();
828 eacr
.p0
= etr_port0_online
;
831 etr_port0_uptodate
= 0;
833 if (test_and_clear_bit(ETR_EVENT_PORT1_CHANGE
, &etr_events
)) {
836 * Port change of an enabled port. We have to
837 * assume that this can have caused an stepping
840 etr_tolec
= get_clock();
841 eacr
.p1
= etr_port1_online
;
844 etr_port1_uptodate
= 0;
846 clear_bit(ETR_EVENT_UPDATE
, &etr_events
);
851 * Set up a timer that expires after the etr_tolec + 1.6 seconds if
852 * one of the ports needs an update.
854 static void etr_set_tolec_timeout(unsigned long long now
)
856 unsigned long micros
;
858 if ((!etr_eacr
.p0
|| etr_port0_uptodate
) &&
859 (!etr_eacr
.p1
|| etr_port1_uptodate
))
861 micros
= (now
> etr_tolec
) ? ((now
- etr_tolec
) >> 12) : 0;
862 micros
= (micros
> 1600000) ? 0 : 1600000 - micros
;
863 mod_timer(&etr_timer
, jiffies
+ (micros
* HZ
) / 1000000 + 1);
867 * Set up a time that expires after 1/2 second.
869 static void etr_set_sync_timeout(void)
871 mod_timer(&etr_timer
, jiffies
+ HZ
/2);
875 * Update the aib information for one or both ports.
877 static struct etr_eacr
etr_handle_update(struct etr_aib
*aib
,
878 struct etr_eacr eacr
)
880 /* With both ports disabled the aib information is useless. */
881 if (!eacr
.e0
&& !eacr
.e1
)
884 /* Update port0 or port1 with aib stored in etr_work_fn. */
885 if (aib
->esw
.q
== 0) {
886 /* Information for port 0 stored. */
887 if (eacr
.p0
&& !etr_port0_uptodate
) {
889 if (etr_port0_online
)
890 etr_port0_uptodate
= 1;
893 /* Information for port 1 stored. */
894 if (eacr
.p1
&& !etr_port1_uptodate
) {
896 if (etr_port0_online
)
897 etr_port1_uptodate
= 1;
902 * Do not try to get the alternate port aib if the clock
903 * is not in sync yet.
905 if (!check_sync_clock())
909 * If steai is available we can get the information about
910 * the other port immediately. If only stetr is available the
911 * data-port bit toggle has to be used.
913 if (etr_steai_available
) {
914 if (eacr
.p0
&& !etr_port0_uptodate
) {
915 etr_steai_cv(&etr_port0
, ETR_STEAI_PORT_0
);
916 etr_port0_uptodate
= 1;
918 if (eacr
.p1
&& !etr_port1_uptodate
) {
919 etr_steai_cv(&etr_port1
, ETR_STEAI_PORT_1
);
920 etr_port1_uptodate
= 1;
924 * One port was updated above, if the other
925 * port is not uptodate toggle dp bit.
927 if ((eacr
.p0
&& !etr_port0_uptodate
) ||
928 (eacr
.p1
&& !etr_port1_uptodate
))
937 * Write new etr control register if it differs from the current one.
938 * Return 1 if etr_tolec has been updated as well.
940 static void etr_update_eacr(struct etr_eacr eacr
)
944 if (memcmp(&etr_eacr
, &eacr
, sizeof(eacr
)) == 0)
945 /* No change, return. */
948 * The disable of an active port of the change of the data port
949 * bit can/will cause a change in the data port.
951 dp_changed
= etr_eacr
.e0
> eacr
.e0
|| etr_eacr
.e1
> eacr
.e1
||
952 (etr_eacr
.dp
^ eacr
.dp
) != 0;
956 etr_tolec
= get_clock();
960 * ETR work. In this function you'll find the main logic. In
961 * particular this is the only function that calls etr_update_eacr(),
962 * it "controls" the etr control register.
964 static void etr_work_fn(struct work_struct
*work
)
966 unsigned long long now
;
967 struct etr_eacr eacr
;
971 /* prevent multiple execution. */
972 mutex_lock(&etr_work_mutex
);
974 /* Create working copy of etr_eacr. */
977 /* Check for the different events and their immediate effects. */
978 eacr
= etr_handle_events(eacr
);
980 /* Check if ETR is supposed to be active. */
981 eacr
.ea
= eacr
.p0
|| eacr
.p1
;
983 /* Both ports offline. Reset everything. */
984 eacr
.dp
= eacr
.es
= eacr
.sl
= 0;
985 on_each_cpu(disable_sync_clock
, NULL
, 1);
986 del_timer_sync(&etr_timer
);
987 etr_update_eacr(eacr
);
991 /* Store aib to get the current ETR status word. */
992 BUG_ON(etr_stetr(&aib
) != 0);
993 etr_port0
.esw
= etr_port1
.esw
= aib
.esw
; /* Copy status word. */
997 * Update the port information if the last stepping port change
998 * or data port change is older than 1.6 seconds.
1000 if (now
>= etr_tolec
+ (1600000 << 12))
1001 eacr
= etr_handle_update(&aib
, eacr
);
1004 * Select ports to enable. The prefered synchronization mode is PPS.
1005 * If a port can be enabled depends on a number of things:
1006 * 1) The port needs to be online and uptodate. A port is not
1007 * disabled just because it is not uptodate, but it is only
1008 * enabled if it is uptodate.
1009 * 2) The port needs to have the same mode (pps / etr).
1010 * 3) The port needs to be usable -> etr_port_valid() == 1
1011 * 4) To enable the second port the clock needs to be in sync.
1012 * 5) If both ports are useable and are ETR ports, the network id
1013 * has to be the same.
1014 * The eacr.sl bit is used to indicate etr mode vs. pps mode.
1016 if (eacr
.p0
&& aib
.esw
.psc0
== etr_lpsc_pps_mode
) {
1019 if (!etr_mode_is_pps(etr_eacr
))
1021 if (!eacr
.es
|| !eacr
.p1
|| aib
.esw
.psc1
!= etr_lpsc_pps_mode
)
1023 // FIXME: uptodate checks ?
1024 else if (etr_port0_uptodate
&& etr_port1_uptodate
)
1026 sync_port
= (etr_port0_uptodate
&&
1027 etr_port_valid(&etr_port0
, 0)) ? 0 : -1;
1028 } else if (eacr
.p1
&& aib
.esw
.psc1
== etr_lpsc_pps_mode
) {
1032 if (!etr_mode_is_pps(etr_eacr
))
1034 sync_port
= (etr_port1_uptodate
&&
1035 etr_port_valid(&etr_port1
, 1)) ? 1 : -1;
1036 } else if (eacr
.p0
&& aib
.esw
.psc0
== etr_lpsc_operational_step
) {
1039 if (!etr_mode_is_etr(etr_eacr
))
1041 if (!eacr
.es
|| !eacr
.p1
||
1042 aib
.esw
.psc1
!= etr_lpsc_operational_alt
)
1044 else if (etr_port0_uptodate
&& etr_port1_uptodate
&&
1045 etr_compare_network(&etr_port0
, &etr_port1
))
1047 sync_port
= (etr_port0_uptodate
&&
1048 etr_port_valid(&etr_port0
, 0)) ? 0 : -1;
1049 } else if (eacr
.p1
&& aib
.esw
.psc1
== etr_lpsc_operational_step
) {
1053 if (!etr_mode_is_etr(etr_eacr
))
1055 sync_port
= (etr_port1_uptodate
&&
1056 etr_port_valid(&etr_port1
, 1)) ? 1 : -1;
1058 /* Both ports not usable. */
1059 eacr
.es
= eacr
.sl
= 0;
1064 * If the clock is in sync just update the eacr and return.
1065 * If there is no valid sync port wait for a port update.
1067 if (check_sync_clock() || sync_port
< 0) {
1068 etr_update_eacr(eacr
);
1069 etr_set_tolec_timeout(now
);
1074 * Prepare control register for clock syncing
1075 * (reset data port bit, set sync check control.
1081 * Update eacr and try to synchronize the clock. If the update
1082 * of eacr caused a stepping port switch (or if we have to
1083 * assume that a stepping port switch has occured) or the
1084 * clock syncing failed, reset the sync check control bit
1085 * and set up a timer to try again after 0.5 seconds
1087 etr_update_eacr(eacr
);
1088 if (now
< etr_tolec
+ (1600000 << 12) ||
1089 etr_sync_clock_stop(&aib
, sync_port
) != 0) {
1090 /* Sync failed. Try again in 1/2 second. */
1092 etr_update_eacr(eacr
);
1093 etr_set_sync_timeout();
1095 etr_set_tolec_timeout(now
);
1097 mutex_unlock(&etr_work_mutex
);
1101 * Sysfs interface functions
1103 static struct sysdev_class etr_sysclass
= {
1107 static struct sys_device etr_port0_dev
= {
1109 .cls
= &etr_sysclass
,
1112 static struct sys_device etr_port1_dev
= {
1114 .cls
= &etr_sysclass
,
1118 * ETR class attributes
1120 static ssize_t
etr_stepping_port_show(struct sysdev_class
*class,
1121 struct sysdev_class_attribute
*attr
,
1124 return sprintf(buf
, "%i\n", etr_port0
.esw
.p
);
1127 static SYSDEV_CLASS_ATTR(stepping_port
, 0400, etr_stepping_port_show
, NULL
);
1129 static ssize_t
etr_stepping_mode_show(struct sysdev_class
*class,
1130 struct sysdev_class_attribute
*attr
,
1135 if (etr_mode_is_pps(etr_eacr
))
1137 else if (etr_mode_is_etr(etr_eacr
))
1141 return sprintf(buf
, "%s\n", mode_str
);
1144 static SYSDEV_CLASS_ATTR(stepping_mode
, 0400, etr_stepping_mode_show
, NULL
);
1147 * ETR port attributes
1149 static inline struct etr_aib
*etr_aib_from_dev(struct sys_device
*dev
)
1151 if (dev
== &etr_port0_dev
)
1152 return etr_port0_online
? &etr_port0
: NULL
;
1154 return etr_port1_online
? &etr_port1
: NULL
;
1157 static ssize_t
etr_online_show(struct sys_device
*dev
,
1158 struct sysdev_attribute
*attr
,
1161 unsigned int online
;
1163 online
= (dev
== &etr_port0_dev
) ? etr_port0_online
: etr_port1_online
;
1164 return sprintf(buf
, "%i\n", online
);
1167 static ssize_t
etr_online_store(struct sys_device
*dev
,
1168 struct sysdev_attribute
*attr
,
1169 const char *buf
, size_t count
)
1173 value
= simple_strtoul(buf
, NULL
, 0);
1174 if (value
!= 0 && value
!= 1)
1176 if (!test_bit(CLOCK_SYNC_HAS_ETR
, &clock_sync_flags
))
1178 mutex_lock(&clock_sync_mutex
);
1179 if (dev
== &etr_port0_dev
) {
1180 if (etr_port0_online
== value
)
1181 goto out
; /* Nothing to do. */
1182 etr_port0_online
= value
;
1183 if (etr_port0_online
&& etr_port1_online
)
1184 set_bit(CLOCK_SYNC_ETR
, &clock_sync_flags
);
1186 clear_bit(CLOCK_SYNC_ETR
, &clock_sync_flags
);
1187 set_bit(ETR_EVENT_PORT0_CHANGE
, &etr_events
);
1188 queue_work(time_sync_wq
, &etr_work
);
1190 if (etr_port1_online
== value
)
1191 goto out
; /* Nothing to do. */
1192 etr_port1_online
= value
;
1193 if (etr_port0_online
&& etr_port1_online
)
1194 set_bit(CLOCK_SYNC_ETR
, &clock_sync_flags
);
1196 clear_bit(CLOCK_SYNC_ETR
, &clock_sync_flags
);
1197 set_bit(ETR_EVENT_PORT1_CHANGE
, &etr_events
);
1198 queue_work(time_sync_wq
, &etr_work
);
1201 mutex_unlock(&clock_sync_mutex
);
1205 static SYSDEV_ATTR(online
, 0600, etr_online_show
, etr_online_store
);
1207 static ssize_t
etr_stepping_control_show(struct sys_device
*dev
,
1208 struct sysdev_attribute
*attr
,
1211 return sprintf(buf
, "%i\n", (dev
== &etr_port0_dev
) ?
1212 etr_eacr
.e0
: etr_eacr
.e1
);
1215 static SYSDEV_ATTR(stepping_control
, 0400, etr_stepping_control_show
, NULL
);
1217 static ssize_t
etr_mode_code_show(struct sys_device
*dev
,
1218 struct sysdev_attribute
*attr
, char *buf
)
1220 if (!etr_port0_online
&& !etr_port1_online
)
1221 /* Status word is not uptodate if both ports are offline. */
1223 return sprintf(buf
, "%i\n", (dev
== &etr_port0_dev
) ?
1224 etr_port0
.esw
.psc0
: etr_port0
.esw
.psc1
);
1227 static SYSDEV_ATTR(state_code
, 0400, etr_mode_code_show
, NULL
);
1229 static ssize_t
etr_untuned_show(struct sys_device
*dev
,
1230 struct sysdev_attribute
*attr
, char *buf
)
1232 struct etr_aib
*aib
= etr_aib_from_dev(dev
);
1234 if (!aib
|| !aib
->slsw
.v1
)
1236 return sprintf(buf
, "%i\n", aib
->edf1
.u
);
1239 static SYSDEV_ATTR(untuned
, 0400, etr_untuned_show
, NULL
);
1241 static ssize_t
etr_network_id_show(struct sys_device
*dev
,
1242 struct sysdev_attribute
*attr
, char *buf
)
1244 struct etr_aib
*aib
= etr_aib_from_dev(dev
);
1246 if (!aib
|| !aib
->slsw
.v1
)
1248 return sprintf(buf
, "%i\n", aib
->edf1
.net_id
);
1251 static SYSDEV_ATTR(network
, 0400, etr_network_id_show
, NULL
);
1253 static ssize_t
etr_id_show(struct sys_device
*dev
,
1254 struct sysdev_attribute
*attr
, char *buf
)
1256 struct etr_aib
*aib
= etr_aib_from_dev(dev
);
1258 if (!aib
|| !aib
->slsw
.v1
)
1260 return sprintf(buf
, "%i\n", aib
->edf1
.etr_id
);
1263 static SYSDEV_ATTR(id
, 0400, etr_id_show
, NULL
);
1265 static ssize_t
etr_port_number_show(struct sys_device
*dev
,
1266 struct sysdev_attribute
*attr
, char *buf
)
1268 struct etr_aib
*aib
= etr_aib_from_dev(dev
);
1270 if (!aib
|| !aib
->slsw
.v1
)
1272 return sprintf(buf
, "%i\n", aib
->edf1
.etr_pn
);
1275 static SYSDEV_ATTR(port
, 0400, etr_port_number_show
, NULL
);
1277 static ssize_t
etr_coupled_show(struct sys_device
*dev
,
1278 struct sysdev_attribute
*attr
, char *buf
)
1280 struct etr_aib
*aib
= etr_aib_from_dev(dev
);
1282 if (!aib
|| !aib
->slsw
.v3
)
1284 return sprintf(buf
, "%i\n", aib
->edf3
.c
);
1287 static SYSDEV_ATTR(coupled
, 0400, etr_coupled_show
, NULL
);
1289 static ssize_t
etr_local_time_show(struct sys_device
*dev
,
1290 struct sysdev_attribute
*attr
, char *buf
)
1292 struct etr_aib
*aib
= etr_aib_from_dev(dev
);
1294 if (!aib
|| !aib
->slsw
.v3
)
1296 return sprintf(buf
, "%i\n", aib
->edf3
.blto
);
1299 static SYSDEV_ATTR(local_time
, 0400, etr_local_time_show
, NULL
);
1301 static ssize_t
etr_utc_offset_show(struct sys_device
*dev
,
1302 struct sysdev_attribute
*attr
, char *buf
)
1304 struct etr_aib
*aib
= etr_aib_from_dev(dev
);
1306 if (!aib
|| !aib
->slsw
.v3
)
1308 return sprintf(buf
, "%i\n", aib
->edf3
.buo
);
1311 static SYSDEV_ATTR(utc_offset
, 0400, etr_utc_offset_show
, NULL
);
1313 static struct sysdev_attribute
*etr_port_attributes
[] = {
1315 &attr_stepping_control
,
1327 static int __init
etr_register_port(struct sys_device
*dev
)
1329 struct sysdev_attribute
**attr
;
1332 rc
= sysdev_register(dev
);
1335 for (attr
= etr_port_attributes
; *attr
; attr
++) {
1336 rc
= sysdev_create_file(dev
, *attr
);
1342 for (; attr
>= etr_port_attributes
; attr
--)
1343 sysdev_remove_file(dev
, *attr
);
1344 sysdev_unregister(dev
);
1349 static void __init
etr_unregister_port(struct sys_device
*dev
)
1351 struct sysdev_attribute
**attr
;
1353 for (attr
= etr_port_attributes
; *attr
; attr
++)
1354 sysdev_remove_file(dev
, *attr
);
1355 sysdev_unregister(dev
);
1358 static int __init
etr_init_sysfs(void)
1362 rc
= sysdev_class_register(&etr_sysclass
);
1365 rc
= sysdev_class_create_file(&etr_sysclass
, &attr_stepping_port
);
1367 goto out_unreg_class
;
1368 rc
= sysdev_class_create_file(&etr_sysclass
, &attr_stepping_mode
);
1370 goto out_remove_stepping_port
;
1371 rc
= etr_register_port(&etr_port0_dev
);
1373 goto out_remove_stepping_mode
;
1374 rc
= etr_register_port(&etr_port1_dev
);
1376 goto out_remove_port0
;
1380 etr_unregister_port(&etr_port0_dev
);
1381 out_remove_stepping_mode
:
1382 sysdev_class_remove_file(&etr_sysclass
, &attr_stepping_mode
);
1383 out_remove_stepping_port
:
1384 sysdev_class_remove_file(&etr_sysclass
, &attr_stepping_port
);
1386 sysdev_class_unregister(&etr_sysclass
);
1391 device_initcall(etr_init_sysfs
);
1394 * Server Time Protocol (STP) code.
1396 static int stp_online
;
1397 static struct stp_sstpi stp_info
;
1398 static void *stp_page
;
1400 static void stp_work_fn(struct work_struct
*work
);
1401 static DEFINE_MUTEX(stp_work_mutex
);
1402 static DECLARE_WORK(stp_work
, stp_work_fn
);
1403 static struct timer_list stp_timer
;
1405 static int __init
early_parse_stp(char *p
)
1407 if (strncmp(p
, "off", 3) == 0)
1409 else if (strncmp(p
, "on", 2) == 0)
1413 early_param("stp", early_parse_stp
);
1416 * Reset STP attachment.
1418 static void __init
stp_reset(void)
1422 stp_page
= (void *) get_zeroed_page(GFP_ATOMIC
);
1423 rc
= chsc_sstpc(stp_page
, STP_OP_CTRL
, 0x0000);
1425 set_bit(CLOCK_SYNC_HAS_STP
, &clock_sync_flags
);
1426 else if (stp_online
) {
1427 pr_warning("The real or virtual hardware system does "
1428 "not provide an STP interface\n");
1429 free_page((unsigned long) stp_page
);
1435 static void stp_timeout(unsigned long dummy
)
1437 queue_work(time_sync_wq
, &stp_work
);
1440 static int __init
stp_init(void)
1442 if (!test_bit(CLOCK_SYNC_HAS_STP
, &clock_sync_flags
))
1444 setup_timer(&stp_timer
, stp_timeout
, 0UL);
1448 queue_work(time_sync_wq
, &stp_work
);
1452 arch_initcall(stp_init
);
1455 * STP timing alert. There are three causes:
1456 * 1) timing status change
1457 * 2) link availability change
1458 * 3) time control parameter change
1459 * In all three cases we are only interested in the clock source state.
1460 * If a STP clock source is now available use it.
1462 static void stp_timing_alert(struct stp_irq_parm
*intparm
)
1464 if (intparm
->tsc
|| intparm
->lac
|| intparm
->tcpc
)
1465 queue_work(time_sync_wq
, &stp_work
);
1469 * STP sync check machine check. This is called when the timing state
1470 * changes from the synchronized state to the unsynchronized state.
1471 * After a STP sync check the clock is not in sync. The machine check
1472 * is broadcasted to all cpus at the same time.
1474 void stp_sync_check(void)
1476 disable_sync_clock(NULL
);
1477 queue_work(time_sync_wq
, &stp_work
);
1481 * STP island condition machine check. This is called when an attached
1482 * server attempts to communicate over an STP link and the servers
1483 * have matching CTN ids and have a valid stratum-1 configuration
1484 * but the configurations do not match.
1486 void stp_island_check(void)
1488 disable_sync_clock(NULL
);
1489 queue_work(time_sync_wq
, &stp_work
);
1493 static int stp_sync_clock(void *data
)
1496 unsigned long long old_clock
, delta
;
1497 struct clock_sync_data
*stp_sync
;
1502 if (xchg(&first
, 1) == 1) {
1504 clock_sync_cpu(stp_sync
);
1508 /* Wait until all other cpus entered the sync function. */
1509 while (atomic_read(&stp_sync
->cpus
) != 0)
1512 enable_sync_clock();
1515 if (stp_info
.todoff
[0] || stp_info
.todoff
[1] ||
1516 stp_info
.todoff
[2] || stp_info
.todoff
[3] ||
1517 stp_info
.tmd
!= 2) {
1518 old_clock
= get_clock();
1519 rc
= chsc_sstpc(stp_page
, STP_OP_SYNC
, 0);
1521 delta
= adjust_time(old_clock
, get_clock(), 0);
1522 fixup_clock_comparator(delta
);
1523 rc
= chsc_sstpi(stp_page
, &stp_info
,
1524 sizeof(struct stp_sstpi
));
1525 if (rc
== 0 && stp_info
.tmd
!= 2)
1530 disable_sync_clock(NULL
);
1531 stp_sync
->in_sync
= -EAGAIN
;
1533 stp_sync
->in_sync
= 1;
1539 * STP work. Check for the STP state and take over the clock
1540 * synchronization if the STP clock source is usable.
1542 static void stp_work_fn(struct work_struct
*work
)
1544 struct clock_sync_data stp_sync
;
1547 /* prevent multiple execution. */
1548 mutex_lock(&stp_work_mutex
);
1551 chsc_sstpc(stp_page
, STP_OP_CTRL
, 0x0000);
1552 del_timer_sync(&stp_timer
);
1556 rc
= chsc_sstpc(stp_page
, STP_OP_CTRL
, 0xb0e0);
1560 rc
= chsc_sstpi(stp_page
, &stp_info
, sizeof(struct stp_sstpi
));
1561 if (rc
|| stp_info
.c
== 0)
1564 /* Skip synchronization if the clock is already in sync. */
1565 if (check_sync_clock())
1568 memset(&stp_sync
, 0, sizeof(stp_sync
));
1570 atomic_set(&stp_sync
.cpus
, num_online_cpus() - 1);
1571 stop_machine(stp_sync_clock
, &stp_sync
, &cpu_online_map
);
1574 if (!check_sync_clock())
1576 * There is a usable clock but the synchonization failed.
1577 * Retry after a second.
1579 mod_timer(&stp_timer
, jiffies
+ HZ
);
1582 mutex_unlock(&stp_work_mutex
);
1586 * STP class sysfs interface functions
1588 static struct sysdev_class stp_sysclass
= {
1592 static ssize_t
stp_ctn_id_show(struct sysdev_class
*class,
1593 struct sysdev_class_attribute
*attr
,
1598 return sprintf(buf
, "%016llx\n",
1599 *(unsigned long long *) stp_info
.ctnid
);
1602 static SYSDEV_CLASS_ATTR(ctn_id
, 0400, stp_ctn_id_show
, NULL
);
1604 static ssize_t
stp_ctn_type_show(struct sysdev_class
*class,
1605 struct sysdev_class_attribute
*attr
,
1610 return sprintf(buf
, "%i\n", stp_info
.ctn
);
1613 static SYSDEV_CLASS_ATTR(ctn_type
, 0400, stp_ctn_type_show
, NULL
);
1615 static ssize_t
stp_dst_offset_show(struct sysdev_class
*class,
1616 struct sysdev_class_attribute
*attr
,
1619 if (!stp_online
|| !(stp_info
.vbits
& 0x2000))
1621 return sprintf(buf
, "%i\n", (int)(s16
) stp_info
.dsto
);
1624 static SYSDEV_CLASS_ATTR(dst_offset
, 0400, stp_dst_offset_show
, NULL
);
1626 static ssize_t
stp_leap_seconds_show(struct sysdev_class
*class,
1627 struct sysdev_class_attribute
*attr
,
1630 if (!stp_online
|| !(stp_info
.vbits
& 0x8000))
1632 return sprintf(buf
, "%i\n", (int)(s16
) stp_info
.leaps
);
1635 static SYSDEV_CLASS_ATTR(leap_seconds
, 0400, stp_leap_seconds_show
, NULL
);
1637 static ssize_t
stp_stratum_show(struct sysdev_class
*class,
1638 struct sysdev_class_attribute
*attr
,
1643 return sprintf(buf
, "%i\n", (int)(s16
) stp_info
.stratum
);
1646 static SYSDEV_CLASS_ATTR(stratum
, 0400, stp_stratum_show
, NULL
);
1648 static ssize_t
stp_time_offset_show(struct sysdev_class
*class,
1649 struct sysdev_class_attribute
*attr
,
1652 if (!stp_online
|| !(stp_info
.vbits
& 0x0800))
1654 return sprintf(buf
, "%i\n", (int) stp_info
.tto
);
1657 static SYSDEV_CLASS_ATTR(time_offset
, 0400, stp_time_offset_show
, NULL
);
1659 static ssize_t
stp_time_zone_offset_show(struct sysdev_class
*class,
1660 struct sysdev_class_attribute
*attr
,
1663 if (!stp_online
|| !(stp_info
.vbits
& 0x4000))
1665 return sprintf(buf
, "%i\n", (int)(s16
) stp_info
.tzo
);
1668 static SYSDEV_CLASS_ATTR(time_zone_offset
, 0400,
1669 stp_time_zone_offset_show
, NULL
);
1671 static ssize_t
stp_timing_mode_show(struct sysdev_class
*class,
1672 struct sysdev_class_attribute
*attr
,
1677 return sprintf(buf
, "%i\n", stp_info
.tmd
);
1680 static SYSDEV_CLASS_ATTR(timing_mode
, 0400, stp_timing_mode_show
, NULL
);
1682 static ssize_t
stp_timing_state_show(struct sysdev_class
*class,
1683 struct sysdev_class_attribute
*attr
,
1688 return sprintf(buf
, "%i\n", stp_info
.tst
);
1691 static SYSDEV_CLASS_ATTR(timing_state
, 0400, stp_timing_state_show
, NULL
);
1693 static ssize_t
stp_online_show(struct sysdev_class
*class,
1694 struct sysdev_class_attribute
*attr
,
1697 return sprintf(buf
, "%i\n", stp_online
);
1700 static ssize_t
stp_online_store(struct sysdev_class
*class,
1701 struct sysdev_class_attribute
*attr
,
1702 const char *buf
, size_t count
)
1706 value
= simple_strtoul(buf
, NULL
, 0);
1707 if (value
!= 0 && value
!= 1)
1709 if (!test_bit(CLOCK_SYNC_HAS_STP
, &clock_sync_flags
))
1711 mutex_lock(&clock_sync_mutex
);
1714 set_bit(CLOCK_SYNC_STP
, &clock_sync_flags
);
1716 clear_bit(CLOCK_SYNC_STP
, &clock_sync_flags
);
1717 queue_work(time_sync_wq
, &stp_work
);
1718 mutex_unlock(&clock_sync_mutex
);
1723 * Can't use SYSDEV_CLASS_ATTR because the attribute should be named
1724 * stp/online but attr_online already exists in this file ..
1726 static struct sysdev_class_attribute attr_stp_online
= {
1727 .attr
= { .name
= "online", .mode
= 0600 },
1728 .show
= stp_online_show
,
1729 .store
= stp_online_store
,
1732 static struct sysdev_class_attribute
*stp_attributes
[] = {
1740 &attr_time_zone_offset
,
1746 static int __init
stp_init_sysfs(void)
1748 struct sysdev_class_attribute
**attr
;
1751 rc
= sysdev_class_register(&stp_sysclass
);
1754 for (attr
= stp_attributes
; *attr
; attr
++) {
1755 rc
= sysdev_class_create_file(&stp_sysclass
, *attr
);
1761 for (; attr
>= stp_attributes
; attr
--)
1762 sysdev_class_remove_file(&stp_sysclass
, *attr
);
1763 sysdev_class_unregister(&stp_sysclass
);
1768 device_initcall(stp_init_sysfs
);