Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /* |
1da177e4 LT |
2 | * Time of day based timer functions. |
3 | * | |
4 | * S390 version | |
d2fec595 | 5 | * Copyright IBM Corp. 1999, 2008 |
1da177e4 LT |
6 | * Author(s): Hartmut Penner (hp@de.ibm.com), |
7 | * Martin Schwidefsky (schwidefsky@de.ibm.com), | |
8 | * Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com) | |
9 | * | |
10 | * Derived from "arch/i386/kernel/time.c" | |
11 | * Copyright (C) 1991, 1992, 1995 Linus Torvalds | |
12 | */ | |
13 | ||
feab6501 MS |
14 | #define KMSG_COMPONENT "time" |
15 | #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt | |
16 | ||
052ff461 | 17 | #include <linux/kernel_stat.h> |
1da177e4 LT |
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> | |
24 | #include <linux/mm.h> | |
25 | #include <linux/interrupt.h> | |
750887de HC |
26 | #include <linux/cpu.h> |
27 | #include <linux/stop_machine.h> | |
1da177e4 | 28 | #include <linux/time.h> |
3fbacffb | 29 | #include <linux/device.h> |
1da177e4 LT |
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> | |
189374ae | 37 | #include <linux/timekeeper_internal.h> |
5a62b192 | 38 | #include <linux/clockchips.h> |
5a0e3ad6 | 39 | #include <linux/gfp.h> |
860dba45 | 40 | #include <linux/kprobes.h> |
1da177e4 | 41 | #include <asm/uaccess.h> |
40277891 | 42 | #include <asm/facility.h> |
1da177e4 | 43 | #include <asm/delay.h> |
1da177e4 | 44 | #include <asm/div64.h> |
b020632e | 45 | #include <asm/vdso.h> |
1da177e4 | 46 | #include <asm/irq.h> |
5a489b98 | 47 | #include <asm/irq_regs.h> |
27f6b416 | 48 | #include <asm/vtimer.h> |
fd5ada04 | 49 | #include <asm/stp.h> |
a806170e | 50 | #include <asm/cio.h> |
638ad34a | 51 | #include "entry.h" |
1da177e4 | 52 | |
b6112ccb | 53 | u64 sched_clock_base_cc = -1; /* Force to data section. */ |
05e7ff7d | 54 | EXPORT_SYMBOL_GPL(sched_clock_base_cc); |
b6112ccb | 55 | |
5a62b192 | 56 | static DEFINE_PER_CPU(struct clock_event_device, comparators); |
1da177e4 | 57 | |
fdf03650 FZ |
58 | ATOMIC_NOTIFIER_HEAD(s390_epoch_delta_notifier); |
59 | EXPORT_SYMBOL(s390_epoch_delta_notifier); | |
60 | ||
40277891 MS |
61 | unsigned char ptff_function_mask[16]; |
62 | unsigned long lpar_offset; | |
936cc855 | 63 | unsigned long initial_leap_seconds; |
40277891 MS |
64 | |
65 | /* | |
66 | * Get time offsets with PTFF | |
67 | */ | |
68 | void __init ptff_init(void) | |
69 | { | |
70 | struct ptff_qto qto; | |
936cc855 | 71 | struct ptff_qui qui; |
40277891 MS |
72 | |
73 | if (!test_facility(28)) | |
74 | return; | |
75 | ptff(&ptff_function_mask, sizeof(ptff_function_mask), PTFF_QAF); | |
76 | ||
77 | /* get LPAR offset */ | |
78 | if (ptff_query(PTFF_QTO) && ptff(&qto, sizeof(qto), PTFF_QTO) == 0) | |
79 | lpar_offset = qto.tod_epoch_difference; | |
936cc855 MS |
80 | |
81 | /* get initial leap seconds */ | |
82 | if (ptff_query(PTFF_QUI) && ptff(&qui, sizeof(qui), PTFF_QUI) == 0) | |
83 | initial_leap_seconds = (unsigned long) | |
84 | ((long) qui.old_leap * 4096000000L); | |
40277891 MS |
85 | } |
86 | ||
1da177e4 LT |
87 | /* |
88 | * Scheduler clock - returns current time in nanosec units. | |
89 | */ | |
7a5388de | 90 | unsigned long long notrace sched_clock(void) |
1da177e4 | 91 | { |
1aae0560 | 92 | return tod_to_ns(get_tod_clock_monotonic()); |
1da177e4 | 93 | } |
7a5388de | 94 | NOKPROBE_SYMBOL(sched_clock); |
1da177e4 | 95 | |
32f65f27 JG |
96 | /* |
97 | * Monotonic_clock - returns # of nanoseconds passed since time_init() | |
98 | */ | |
99 | unsigned long long monotonic_clock(void) | |
100 | { | |
101 | return sched_clock(); | |
102 | } | |
103 | EXPORT_SYMBOL(monotonic_clock); | |
104 | ||
689911c7 | 105 | void tod_to_timeval(__u64 todval, struct timespec64 *xt) |
1da177e4 LT |
106 | { |
107 | unsigned long long sec; | |
108 | ||
109 | sec = todval >> 12; | |
110 | do_div(sec, 1000000); | |
b1e2ba8d | 111 | xt->tv_sec = sec; |
1da177e4 | 112 | todval -= (sec * 1000000) << 12; |
b1e2ba8d | 113 | xt->tv_nsec = ((todval * 1000) >> 12); |
1da177e4 | 114 | } |
b592e89a | 115 | EXPORT_SYMBOL(tod_to_timeval); |
1da177e4 | 116 | |
5a62b192 | 117 | void clock_comparator_work(void) |
1da177e4 | 118 | { |
5a62b192 | 119 | struct clock_event_device *cd; |
1da177e4 | 120 | |
5a62b192 | 121 | S390_lowcore.clock_comparator = -1ULL; |
eb7e7d76 | 122 | cd = this_cpu_ptr(&comparators); |
5a62b192 | 123 | cd->event_handler(cd); |
1da177e4 LT |
124 | } |
125 | ||
1da177e4 | 126 | /* |
5a62b192 | 127 | * Fixup the clock comparator. |
1da177e4 | 128 | */ |
5a62b192 | 129 | static void fixup_clock_comparator(unsigned long long delta) |
1da177e4 | 130 | { |
5a62b192 HC |
131 | /* If nobody is waiting there's nothing to fix. */ |
132 | if (S390_lowcore.clock_comparator == -1ULL) | |
1da177e4 | 133 | return; |
5a62b192 HC |
134 | S390_lowcore.clock_comparator += delta; |
135 | set_clock_comparator(S390_lowcore.clock_comparator); | |
1da177e4 LT |
136 | } |
137 | ||
8adbf78e | 138 | static int s390_next_event(unsigned long delta, |
5a62b192 | 139 | struct clock_event_device *evt) |
1da177e4 | 140 | { |
8adbf78e | 141 | S390_lowcore.clock_comparator = get_tod_clock() + delta; |
5a62b192 HC |
142 | set_clock_comparator(S390_lowcore.clock_comparator); |
143 | return 0; | |
1da177e4 LT |
144 | } |
145 | ||
d54853ef MS |
146 | /* |
147 | * Set up lowcore and control register of the current cpu to | |
148 | * enable TOD clock and clock comparator interrupts. | |
1da177e4 LT |
149 | */ |
150 | void init_cpu_timer(void) | |
151 | { | |
5a62b192 HC |
152 | struct clock_event_device *cd; |
153 | int cpu; | |
154 | ||
155 | S390_lowcore.clock_comparator = -1ULL; | |
156 | set_clock_comparator(S390_lowcore.clock_comparator); | |
157 | ||
158 | cpu = smp_processor_id(); | |
159 | cd = &per_cpu(comparators, cpu); | |
160 | cd->name = "comparator"; | |
8adbf78e | 161 | cd->features = CLOCK_EVT_FEAT_ONESHOT; |
5a62b192 HC |
162 | cd->mult = 16777; |
163 | cd->shift = 12; | |
164 | cd->min_delta_ns = 1; | |
165 | cd->max_delta_ns = LONG_MAX; | |
166 | cd->rating = 400; | |
320ab2b0 | 167 | cd->cpumask = cpumask_of(cpu); |
8adbf78e | 168 | cd->set_next_event = s390_next_event; |
5a62b192 HC |
169 | |
170 | clockevents_register_device(cd); | |
d54853ef MS |
171 | |
172 | /* Enable clock comparator timer interrupt. */ | |
173 | __ctl_set_bit(0,11); | |
174 | ||
d2fec595 | 175 | /* Always allow the timing alert external interrupt. */ |
d54853ef MS |
176 | __ctl_set_bit(0, 4); |
177 | } | |
178 | ||
fde15c3a | 179 | static void clock_comparator_interrupt(struct ext_code ext_code, |
f6649a7e MS |
180 | unsigned int param32, |
181 | unsigned long param64) | |
d54853ef | 182 | { |
420f42ec | 183 | inc_irq_stat(IRQEXT_CLK); |
d3d238c7 HC |
184 | if (S390_lowcore.clock_comparator == -1ULL) |
185 | set_clock_comparator(S390_lowcore.clock_comparator); | |
d54853ef MS |
186 | } |
187 | ||
d2fec595 MS |
188 | static void stp_timing_alert(struct stp_irq_parm *); |
189 | ||
fde15c3a | 190 | static void timing_alert_interrupt(struct ext_code ext_code, |
f6649a7e | 191 | unsigned int param32, unsigned long param64) |
d2fec595 | 192 | { |
420f42ec | 193 | inc_irq_stat(IRQEXT_TLA); |
f6649a7e MS |
194 | if (param32 & 0x00038000) |
195 | stp_timing_alert((struct stp_irq_parm *) ¶m32); | |
d2fec595 MS |
196 | } |
197 | ||
d2fec595 | 198 | static void stp_reset(void); |
d54853ef | 199 | |
689911c7 | 200 | void read_persistent_clock64(struct timespec64 *ts) |
d54853ef | 201 | { |
936cc855 MS |
202 | __u64 clock; |
203 | ||
204 | clock = get_tod_clock() - initial_leap_seconds; | |
205 | tod_to_timeval(clock - TOD_UNIX_EPOCH, ts); | |
1da177e4 | 206 | } |
d54853ef | 207 | |
689911c7 | 208 | void read_boot_clock64(struct timespec64 *ts) |
23970e38 | 209 | { |
936cc855 MS |
210 | __u64 clock; |
211 | ||
212 | clock = sched_clock_base_cc - initial_leap_seconds; | |
213 | tod_to_timeval(clock - TOD_UNIX_EPOCH, ts); | |
1da177e4 LT |
214 | } |
215 | ||
8e19608e | 216 | static cycle_t read_tod_clock(struct clocksource *cs) |
dc64bef5 | 217 | { |
1aae0560 | 218 | return get_tod_clock(); |
dc64bef5 MS |
219 | } |
220 | ||
221 | static struct clocksource clocksource_tod = { | |
222 | .name = "tod", | |
d2cb0e6e | 223 | .rating = 400, |
dc64bef5 MS |
224 | .read = read_tod_clock, |
225 | .mask = -1ULL, | |
226 | .mult = 1000, | |
227 | .shift = 12, | |
cc02d809 | 228 | .flags = CLOCK_SOURCE_IS_CONTINUOUS, |
dc64bef5 MS |
229 | }; |
230 | ||
f1b82746 MS |
231 | struct clocksource * __init clocksource_default_clock(void) |
232 | { | |
233 | return &clocksource_tod; | |
234 | } | |
dc64bef5 | 235 | |
79c74ecb | 236 | void update_vsyscall(struct timekeeper *tk) |
b020632e | 237 | { |
79c74ecb MS |
238 | u64 nsecps; |
239 | ||
876e7881 | 240 | if (tk->tkr_mono.clock != &clocksource_tod) |
b020632e MS |
241 | return; |
242 | ||
243 | /* Make userspace gettimeofday spin until we're done. */ | |
244 | ++vdso_data->tb_update_count; | |
245 | smp_wmb(); | |
876e7881 | 246 | vdso_data->xtime_tod_stamp = tk->tkr_mono.cycle_last; |
79c74ecb | 247 | vdso_data->xtime_clock_sec = tk->xtime_sec; |
876e7881 | 248 | vdso_data->xtime_clock_nsec = tk->tkr_mono.xtime_nsec; |
79c74ecb MS |
249 | vdso_data->wtom_clock_sec = |
250 | tk->xtime_sec + tk->wall_to_monotonic.tv_sec; | |
876e7881 PZ |
251 | vdso_data->wtom_clock_nsec = tk->tkr_mono.xtime_nsec + |
252 | + ((u64) tk->wall_to_monotonic.tv_nsec << tk->tkr_mono.shift); | |
253 | nsecps = (u64) NSEC_PER_SEC << tk->tkr_mono.shift; | |
79c74ecb MS |
254 | while (vdso_data->wtom_clock_nsec >= nsecps) { |
255 | vdso_data->wtom_clock_nsec -= nsecps; | |
256 | vdso_data->wtom_clock_sec++; | |
257 | } | |
b7eacb59 MS |
258 | |
259 | vdso_data->xtime_coarse_sec = tk->xtime_sec; | |
260 | vdso_data->xtime_coarse_nsec = | |
876e7881 | 261 | (long)(tk->tkr_mono.xtime_nsec >> tk->tkr_mono.shift); |
b7eacb59 MS |
262 | vdso_data->wtom_coarse_sec = |
263 | vdso_data->xtime_coarse_sec + tk->wall_to_monotonic.tv_sec; | |
264 | vdso_data->wtom_coarse_nsec = | |
265 | vdso_data->xtime_coarse_nsec + tk->wall_to_monotonic.tv_nsec; | |
266 | while (vdso_data->wtom_coarse_nsec >= NSEC_PER_SEC) { | |
267 | vdso_data->wtom_coarse_nsec -= NSEC_PER_SEC; | |
268 | vdso_data->wtom_coarse_sec++; | |
269 | } | |
270 | ||
876e7881 PZ |
271 | vdso_data->tk_mult = tk->tkr_mono.mult; |
272 | vdso_data->tk_shift = tk->tkr_mono.shift; | |
b020632e MS |
273 | smp_wmb(); |
274 | ++vdso_data->tb_update_count; | |
275 | } | |
276 | ||
277 | extern struct timezone sys_tz; | |
278 | ||
279 | void update_vsyscall_tz(void) | |
280 | { | |
b020632e MS |
281 | vdso_data->tz_minuteswest = sys_tz.tz_minuteswest; |
282 | vdso_data->tz_dsttime = sys_tz.tz_dsttime; | |
b020632e MS |
283 | } |
284 | ||
1da177e4 LT |
285 | /* |
286 | * Initialize the TOD clock and the CPU timer of | |
287 | * the boot cpu. | |
288 | */ | |
289 | void __init time_init(void) | |
290 | { | |
b6112ccb | 291 | /* Reset time synchronization interfaces. */ |
b6112ccb | 292 | stp_reset(); |
1da177e4 | 293 | |
1da177e4 | 294 | /* request the clock comparator external interrupt */ |
1dad093b TH |
295 | if (register_external_irq(EXT_IRQ_CLK_COMP, clock_comparator_interrupt)) |
296 | panic("Couldn't request external interrupt 0x1004"); | |
1da177e4 | 297 | |
d2fec595 | 298 | /* request the timing alert external interrupt */ |
1dad093b | 299 | if (register_external_irq(EXT_IRQ_TIMING_ALERT, timing_alert_interrupt)) |
d54853ef MS |
300 | panic("Couldn't request external interrupt 0x1406"); |
301 | ||
f8935983 | 302 | if (__clocksource_register(&clocksource_tod) != 0) |
ab96e798 MS |
303 | panic("Could not register TOD clock source"); |
304 | ||
d54853ef MS |
305 | /* Enable TOD clock interrupts on the boot cpu. */ |
306 | init_cpu_timer(); | |
ab96e798 | 307 | |
c185b783 | 308 | /* Enable cpu timer interrupts on the boot cpu. */ |
1da177e4 | 309 | vtime_init(); |
d54853ef MS |
310 | } |
311 | ||
d2fec595 | 312 | static DEFINE_PER_CPU(atomic_t, clock_sync_word); |
8283cb43 | 313 | static DEFINE_MUTEX(clock_sync_mutex); |
d2fec595 MS |
314 | static unsigned long clock_sync_flags; |
315 | ||
ca64f639 DH |
316 | #define CLOCK_SYNC_HAS_STP 0 |
317 | #define CLOCK_SYNC_STP 1 | |
d2fec595 MS |
318 | |
319 | /* | |
40277891 MS |
320 | * The get_clock function for the physical clock. It will get the current |
321 | * TOD clock, subtract the LPAR offset and write the result to *clock. | |
322 | * The function returns 0 if the clock is in sync with the external time | |
323 | * source. If the clock mode is local it will return -EOPNOTSUPP and | |
324 | * -EAGAIN if the clock is not in sync with the external reference. | |
d2fec595 | 325 | */ |
40277891 | 326 | int get_phys_clock(unsigned long long *clock) |
d2fec595 MS |
327 | { |
328 | atomic_t *sw_ptr; | |
329 | unsigned int sw0, sw1; | |
330 | ||
331 | sw_ptr = &get_cpu_var(clock_sync_word); | |
332 | sw0 = atomic_read(sw_ptr); | |
40277891 | 333 | *clock = get_tod_clock() - lpar_offset; |
d2fec595 | 334 | sw1 = atomic_read(sw_ptr); |
bd119ee2 | 335 | put_cpu_var(clock_sync_word); |
d2fec595 MS |
336 | if (sw0 == sw1 && (sw0 & 0x80000000U)) |
337 | /* Success: time is in sync. */ | |
338 | return 0; | |
ca64f639 | 339 | if (!test_bit(CLOCK_SYNC_HAS_STP, &clock_sync_flags)) |
a8f6db4d | 340 | return -EOPNOTSUPP; |
ca64f639 | 341 | if (!test_bit(CLOCK_SYNC_STP, &clock_sync_flags)) |
d2fec595 MS |
342 | return -EACCES; |
343 | return -EAGAIN; | |
344 | } | |
40277891 | 345 | EXPORT_SYMBOL(get_phys_clock); |
d2fec595 MS |
346 | |
347 | /* | |
ca64f639 | 348 | * Make get_phys_clock() return -EAGAIN. |
d2fec595 MS |
349 | */ |
350 | static void disable_sync_clock(void *dummy) | |
351 | { | |
eb7e7d76 | 352 | atomic_t *sw_ptr = this_cpu_ptr(&clock_sync_word); |
d2fec595 | 353 | /* |
ca64f639 | 354 | * Clear the in-sync bit 2^31. All get_phys_clock calls will |
d2fec595 MS |
355 | * fail until the sync bit is turned back on. In addition |
356 | * increase the "sequence" counter to avoid the race of an | |
ca64f639 | 357 | * stp event and the complete recovery against get_phys_clock. |
d2fec595 | 358 | */ |
805de8f4 | 359 | atomic_andnot(0x80000000, sw_ptr); |
d2fec595 MS |
360 | atomic_inc(sw_ptr); |
361 | } | |
362 | ||
363 | /* | |
ca64f639 | 364 | * Make get_phys_clock() return 0 again. |
d2fec595 MS |
365 | * Needs to be called from a context disabled for preemption. |
366 | */ | |
367 | static void enable_sync_clock(void) | |
368 | { | |
eb7e7d76 | 369 | atomic_t *sw_ptr = this_cpu_ptr(&clock_sync_word); |
805de8f4 | 370 | atomic_or(0x80000000, sw_ptr); |
d2fec595 MS |
371 | } |
372 | ||
8283cb43 MS |
373 | /* |
374 | * Function to check if the clock is in sync. | |
375 | */ | |
376 | static inline int check_sync_clock(void) | |
377 | { | |
378 | atomic_t *sw_ptr; | |
379 | int rc; | |
380 | ||
381 | sw_ptr = &get_cpu_var(clock_sync_word); | |
382 | rc = (atomic_read(sw_ptr) & 0x80000000U) != 0; | |
bd119ee2 | 383 | put_cpu_var(clock_sync_word); |
8283cb43 MS |
384 | return rc; |
385 | } | |
386 | ||
ca64f639 | 387 | /* Single threaded workqueue used for stp sync events */ |
750887de HC |
388 | static struct workqueue_struct *time_sync_wq; |
389 | ||
390 | static void __init time_init_wq(void) | |
391 | { | |
179cb81a HC |
392 | if (time_sync_wq) |
393 | return; | |
394 | time_sync_wq = create_singlethread_workqueue("timesync"); | |
750887de HC |
395 | } |
396 | ||
d2fec595 | 397 | struct clock_sync_data { |
750887de | 398 | atomic_t cpus; |
5a62b192 HC |
399 | int in_sync; |
400 | unsigned long long fixup_cc; | |
d2fec595 | 401 | }; |
5a62b192 | 402 | |
750887de | 403 | static void clock_sync_cpu(struct clock_sync_data *sync) |
d54853ef | 404 | { |
750887de | 405 | atomic_dec(&sync->cpus); |
d2fec595 | 406 | enable_sync_clock(); |
d2fec595 | 407 | while (sync->in_sync == 0) { |
d54853ef | 408 | __udelay(1); |
6c732de2 HC |
409 | /* |
410 | * A different cpu changes *in_sync. Therefore use | |
411 | * barrier() to force memory access. | |
412 | */ | |
413 | barrier(); | |
414 | } | |
d2fec595 | 415 | if (sync->in_sync != 1) |
d54853ef | 416 | /* Didn't work. Clear per-cpu in sync bit again. */ |
d2fec595 | 417 | disable_sync_clock(NULL); |
d54853ef MS |
418 | /* |
419 | * This round of TOD syncing is done. Set the clock comparator | |
420 | * to the next tick and let the processor continue. | |
421 | */ | |
d2fec595 | 422 | fixup_clock_comparator(sync->fixup_cc); |
d54853ef MS |
423 | } |
424 | ||
d2fec595 MS |
425 | /* |
426 | * Server Time Protocol (STP) code. | |
427 | */ | |
4cc7ecb7 | 428 | static bool stp_online; |
d2fec595 MS |
429 | static struct stp_sstpi stp_info; |
430 | static void *stp_page; | |
431 | ||
432 | static void stp_work_fn(struct work_struct *work); | |
0b3016b7 | 433 | static DEFINE_MUTEX(stp_work_mutex); |
d2fec595 | 434 | static DECLARE_WORK(stp_work, stp_work_fn); |
04362301 | 435 | static struct timer_list stp_timer; |
d2fec595 MS |
436 | |
437 | static int __init early_parse_stp(char *p) | |
438 | { | |
4cc7ecb7 | 439 | return kstrtobool(p, &stp_online); |
d2fec595 MS |
440 | } |
441 | early_param("stp", early_parse_stp); | |
442 | ||
443 | /* | |
444 | * Reset STP attachment. | |
445 | */ | |
8f847003 | 446 | static void __init stp_reset(void) |
d2fec595 MS |
447 | { |
448 | int rc; | |
449 | ||
d7d1104f | 450 | stp_page = (void *) get_zeroed_page(GFP_ATOMIC); |
2f82f577 | 451 | rc = chsc_sstpc(stp_page, STP_OP_CTRL, 0x0000, NULL); |
4a672cfa | 452 | if (rc == 0) |
d2fec595 MS |
453 | set_bit(CLOCK_SYNC_HAS_STP, &clock_sync_flags); |
454 | else if (stp_online) { | |
baebc70a | 455 | pr_warn("The real or virtual hardware system does not provide an STP interface\n"); |
d7d1104f | 456 | free_page((unsigned long) stp_page); |
d2fec595 MS |
457 | stp_page = NULL; |
458 | stp_online = 0; | |
459 | } | |
460 | } | |
461 | ||
04362301 MS |
462 | static void stp_timeout(unsigned long dummy) |
463 | { | |
464 | queue_work(time_sync_wq, &stp_work); | |
465 | } | |
466 | ||
d2fec595 MS |
467 | static int __init stp_init(void) |
468 | { | |
750887de HC |
469 | if (!test_bit(CLOCK_SYNC_HAS_STP, &clock_sync_flags)) |
470 | return 0; | |
04362301 | 471 | setup_timer(&stp_timer, stp_timeout, 0UL); |
750887de HC |
472 | time_init_wq(); |
473 | if (!stp_online) | |
474 | return 0; | |
475 | queue_work(time_sync_wq, &stp_work); | |
d2fec595 MS |
476 | return 0; |
477 | } | |
478 | ||
479 | arch_initcall(stp_init); | |
480 | ||
481 | /* | |
482 | * STP timing alert. There are three causes: | |
483 | * 1) timing status change | |
484 | * 2) link availability change | |
485 | * 3) time control parameter change | |
486 | * In all three cases we are only interested in the clock source state. | |
487 | * If a STP clock source is now available use it. | |
488 | */ | |
489 | static void stp_timing_alert(struct stp_irq_parm *intparm) | |
490 | { | |
491 | if (intparm->tsc || intparm->lac || intparm->tcpc) | |
750887de | 492 | queue_work(time_sync_wq, &stp_work); |
d2fec595 MS |
493 | } |
494 | ||
495 | /* | |
496 | * STP sync check machine check. This is called when the timing state | |
497 | * changes from the synchronized state to the unsynchronized state. | |
498 | * After a STP sync check the clock is not in sync. The machine check | |
499 | * is broadcasted to all cpus at the same time. | |
500 | */ | |
29b0a825 | 501 | int stp_sync_check(void) |
d2fec595 | 502 | { |
d2fec595 | 503 | disable_sync_clock(NULL); |
29b0a825 | 504 | return 1; |
d2fec595 MS |
505 | } |
506 | ||
507 | /* | |
508 | * STP island condition machine check. This is called when an attached | |
509 | * server attempts to communicate over an STP link and the servers | |
510 | * have matching CTN ids and have a valid stratum-1 configuration | |
511 | * but the configurations do not match. | |
512 | */ | |
29b0a825 | 513 | int stp_island_check(void) |
d2fec595 | 514 | { |
d2fec595 | 515 | disable_sync_clock(NULL); |
29b0a825 | 516 | return 1; |
d2fec595 MS |
517 | } |
518 | ||
29b0a825 HC |
519 | void stp_queue_work(void) |
520 | { | |
521 | queue_work(time_sync_wq, &stp_work); | |
522 | } | |
750887de HC |
523 | |
524 | static int stp_sync_clock(void *data) | |
d2fec595 | 525 | { |
750887de | 526 | static int first; |
41ad0220 | 527 | unsigned long long clock_delta; |
750887de | 528 | struct clock_sync_data *stp_sync; |
40277891 | 529 | struct ptff_qto qto; |
d2fec595 MS |
530 | int rc; |
531 | ||
750887de | 532 | stp_sync = data; |
d2fec595 | 533 | |
750887de HC |
534 | if (xchg(&first, 1) == 1) { |
535 | /* Slave */ | |
536 | clock_sync_cpu(stp_sync); | |
537 | return 0; | |
538 | } | |
d2fec595 | 539 | |
750887de HC |
540 | /* Wait until all other cpus entered the sync function. */ |
541 | while (atomic_read(&stp_sync->cpus) != 0) | |
542 | cpu_relax(); | |
d2fec595 | 543 | |
d2fec595 MS |
544 | enable_sync_clock(); |
545 | ||
d2fec595 MS |
546 | rc = 0; |
547 | if (stp_info.todoff[0] || stp_info.todoff[1] || | |
548 | stp_info.todoff[2] || stp_info.todoff[3] || | |
549 | stp_info.tmd != 2) { | |
2f82f577 | 550 | rc = chsc_sstpc(stp_page, STP_OP_SYNC, 0, &clock_delta); |
d2fec595 | 551 | if (rc == 0) { |
41ad0220 DH |
552 | /* fixup the monotonic sched clock */ |
553 | sched_clock_base_cc += clock_delta; | |
40277891 MS |
554 | if (ptff_query(PTFF_QTO) && |
555 | ptff(&qto, sizeof(qto), PTFF_QTO) == 0) | |
556 | /* Update LPAR offset */ | |
557 | lpar_offset = qto.tod_epoch_difference; | |
fdf03650 FZ |
558 | atomic_notifier_call_chain(&s390_epoch_delta_notifier, |
559 | 0, &clock_delta); | |
0c00b1e0 | 560 | stp_sync->fixup_cc = clock_delta; |
41ad0220 | 561 | fixup_clock_comparator(clock_delta); |
d2fec595 MS |
562 | rc = chsc_sstpi(stp_page, &stp_info, |
563 | sizeof(struct stp_sstpi)); | |
564 | if (rc == 0 && stp_info.tmd != 2) | |
565 | rc = -EAGAIN; | |
566 | } | |
567 | } | |
568 | if (rc) { | |
569 | disable_sync_clock(NULL); | |
750887de | 570 | stp_sync->in_sync = -EAGAIN; |
d2fec595 | 571 | } else |
750887de HC |
572 | stp_sync->in_sync = 1; |
573 | xchg(&first, 0); | |
574 | return 0; | |
575 | } | |
d2fec595 | 576 | |
750887de HC |
577 | /* |
578 | * STP work. Check for the STP state and take over the clock | |
579 | * synchronization if the STP clock source is usable. | |
580 | */ | |
581 | static void stp_work_fn(struct work_struct *work) | |
582 | { | |
583 | struct clock_sync_data stp_sync; | |
584 | int rc; | |
585 | ||
0b3016b7 MS |
586 | /* prevent multiple execution. */ |
587 | mutex_lock(&stp_work_mutex); | |
588 | ||
750887de | 589 | if (!stp_online) { |
2f82f577 | 590 | chsc_sstpc(stp_page, STP_OP_CTRL, 0x0000, NULL); |
04362301 | 591 | del_timer_sync(&stp_timer); |
0b3016b7 | 592 | goto out_unlock; |
750887de HC |
593 | } |
594 | ||
2f82f577 | 595 | rc = chsc_sstpc(stp_page, STP_OP_CTRL, 0xb0e0, NULL); |
750887de | 596 | if (rc) |
0b3016b7 | 597 | goto out_unlock; |
750887de HC |
598 | |
599 | rc = chsc_sstpi(stp_page, &stp_info, sizeof(struct stp_sstpi)); | |
600 | if (rc || stp_info.c == 0) | |
0b3016b7 | 601 | goto out_unlock; |
750887de | 602 | |
8283cb43 MS |
603 | /* Skip synchronization if the clock is already in sync. */ |
604 | if (check_sync_clock()) | |
605 | goto out_unlock; | |
606 | ||
750887de HC |
607 | memset(&stp_sync, 0, sizeof(stp_sync)); |
608 | get_online_cpus(); | |
609 | atomic_set(&stp_sync.cpus, num_online_cpus() - 1); | |
0f1959f5 | 610 | stop_machine(stp_sync_clock, &stp_sync, cpu_online_mask); |
750887de | 611 | put_online_cpus(); |
0b3016b7 | 612 | |
04362301 MS |
613 | if (!check_sync_clock()) |
614 | /* | |
615 | * There is a usable clock but the synchonization failed. | |
616 | * Retry after a second. | |
617 | */ | |
618 | mod_timer(&stp_timer, jiffies + HZ); | |
619 | ||
0b3016b7 MS |
620 | out_unlock: |
621 | mutex_unlock(&stp_work_mutex); | |
d2fec595 MS |
622 | } |
623 | ||
624 | /* | |
3fbacffb | 625 | * STP subsys sysfs interface functions |
d2fec595 | 626 | */ |
3fbacffb KS |
627 | static struct bus_type stp_subsys = { |
628 | .name = "stp", | |
629 | .dev_name = "stp", | |
d2fec595 MS |
630 | }; |
631 | ||
3fbacffb KS |
632 | static ssize_t stp_ctn_id_show(struct device *dev, |
633 | struct device_attribute *attr, | |
c9be0a36 | 634 | char *buf) |
d2fec595 MS |
635 | { |
636 | if (!stp_online) | |
637 | return -ENODATA; | |
638 | return sprintf(buf, "%016llx\n", | |
639 | *(unsigned long long *) stp_info.ctnid); | |
640 | } | |
641 | ||
3fbacffb | 642 | static DEVICE_ATTR(ctn_id, 0400, stp_ctn_id_show, NULL); |
d2fec595 | 643 | |
3fbacffb KS |
644 | static ssize_t stp_ctn_type_show(struct device *dev, |
645 | struct device_attribute *attr, | |
c9be0a36 | 646 | char *buf) |
d2fec595 MS |
647 | { |
648 | if (!stp_online) | |
649 | return -ENODATA; | |
650 | return sprintf(buf, "%i\n", stp_info.ctn); | |
651 | } | |
652 | ||
3fbacffb | 653 | static DEVICE_ATTR(ctn_type, 0400, stp_ctn_type_show, NULL); |
d2fec595 | 654 | |
3fbacffb KS |
655 | static ssize_t stp_dst_offset_show(struct device *dev, |
656 | struct device_attribute *attr, | |
c9be0a36 | 657 | char *buf) |
d2fec595 MS |
658 | { |
659 | if (!stp_online || !(stp_info.vbits & 0x2000)) | |
660 | return -ENODATA; | |
661 | return sprintf(buf, "%i\n", (int)(s16) stp_info.dsto); | |
662 | } | |
663 | ||
3fbacffb | 664 | static DEVICE_ATTR(dst_offset, 0400, stp_dst_offset_show, NULL); |
d2fec595 | 665 | |
3fbacffb KS |
666 | static ssize_t stp_leap_seconds_show(struct device *dev, |
667 | struct device_attribute *attr, | |
c9be0a36 | 668 | char *buf) |
d2fec595 MS |
669 | { |
670 | if (!stp_online || !(stp_info.vbits & 0x8000)) | |
671 | return -ENODATA; | |
672 | return sprintf(buf, "%i\n", (int)(s16) stp_info.leaps); | |
673 | } | |
674 | ||
3fbacffb | 675 | static DEVICE_ATTR(leap_seconds, 0400, stp_leap_seconds_show, NULL); |
d2fec595 | 676 | |
3fbacffb KS |
677 | static ssize_t stp_stratum_show(struct device *dev, |
678 | struct device_attribute *attr, | |
c9be0a36 | 679 | char *buf) |
d2fec595 MS |
680 | { |
681 | if (!stp_online) | |
682 | return -ENODATA; | |
683 | return sprintf(buf, "%i\n", (int)(s16) stp_info.stratum); | |
684 | } | |
685 | ||
3fbacffb | 686 | static DEVICE_ATTR(stratum, 0400, stp_stratum_show, NULL); |
d2fec595 | 687 | |
3fbacffb KS |
688 | static ssize_t stp_time_offset_show(struct device *dev, |
689 | struct device_attribute *attr, | |
c9be0a36 | 690 | char *buf) |
d2fec595 MS |
691 | { |
692 | if (!stp_online || !(stp_info.vbits & 0x0800)) | |
693 | return -ENODATA; | |
694 | return sprintf(buf, "%i\n", (int) stp_info.tto); | |
695 | } | |
696 | ||
3fbacffb | 697 | static DEVICE_ATTR(time_offset, 0400, stp_time_offset_show, NULL); |
d2fec595 | 698 | |
3fbacffb KS |
699 | static ssize_t stp_time_zone_offset_show(struct device *dev, |
700 | struct device_attribute *attr, | |
c9be0a36 | 701 | char *buf) |
d2fec595 MS |
702 | { |
703 | if (!stp_online || !(stp_info.vbits & 0x4000)) | |
704 | return -ENODATA; | |
705 | return sprintf(buf, "%i\n", (int)(s16) stp_info.tzo); | |
706 | } | |
707 | ||
3fbacffb | 708 | static DEVICE_ATTR(time_zone_offset, 0400, |
d2fec595 MS |
709 | stp_time_zone_offset_show, NULL); |
710 | ||
3fbacffb KS |
711 | static ssize_t stp_timing_mode_show(struct device *dev, |
712 | struct device_attribute *attr, | |
c9be0a36 | 713 | char *buf) |
d2fec595 MS |
714 | { |
715 | if (!stp_online) | |
716 | return -ENODATA; | |
717 | return sprintf(buf, "%i\n", stp_info.tmd); | |
718 | } | |
719 | ||
3fbacffb | 720 | static DEVICE_ATTR(timing_mode, 0400, stp_timing_mode_show, NULL); |
d2fec595 | 721 | |
3fbacffb KS |
722 | static ssize_t stp_timing_state_show(struct device *dev, |
723 | struct device_attribute *attr, | |
c9be0a36 | 724 | char *buf) |
d2fec595 MS |
725 | { |
726 | if (!stp_online) | |
727 | return -ENODATA; | |
728 | return sprintf(buf, "%i\n", stp_info.tst); | |
729 | } | |
730 | ||
3fbacffb | 731 | static DEVICE_ATTR(timing_state, 0400, stp_timing_state_show, NULL); |
d2fec595 | 732 | |
3fbacffb KS |
733 | static ssize_t stp_online_show(struct device *dev, |
734 | struct device_attribute *attr, | |
c9be0a36 | 735 | char *buf) |
d2fec595 MS |
736 | { |
737 | return sprintf(buf, "%i\n", stp_online); | |
738 | } | |
739 | ||
3fbacffb KS |
740 | static ssize_t stp_online_store(struct device *dev, |
741 | struct device_attribute *attr, | |
d2fec595 MS |
742 | const char *buf, size_t count) |
743 | { | |
744 | unsigned int value; | |
745 | ||
746 | value = simple_strtoul(buf, NULL, 0); | |
747 | if (value != 0 && value != 1) | |
748 | return -EINVAL; | |
749 | if (!test_bit(CLOCK_SYNC_HAS_STP, &clock_sync_flags)) | |
750 | return -EOPNOTSUPP; | |
8283cb43 | 751 | mutex_lock(&clock_sync_mutex); |
d2fec595 | 752 | stp_online = value; |
8283cb43 MS |
753 | if (stp_online) |
754 | set_bit(CLOCK_SYNC_STP, &clock_sync_flags); | |
755 | else | |
756 | clear_bit(CLOCK_SYNC_STP, &clock_sync_flags); | |
750887de | 757 | queue_work(time_sync_wq, &stp_work); |
8283cb43 | 758 | mutex_unlock(&clock_sync_mutex); |
d2fec595 MS |
759 | return count; |
760 | } | |
761 | ||
762 | /* | |
3fbacffb KS |
763 | * Can't use DEVICE_ATTR because the attribute should be named |
764 | * stp/online but dev_attr_online already exists in this file .. | |
d2fec595 | 765 | */ |
3fbacffb | 766 | static struct device_attribute dev_attr_stp_online = { |
d2fec595 MS |
767 | .attr = { .name = "online", .mode = 0600 }, |
768 | .show = stp_online_show, | |
769 | .store = stp_online_store, | |
770 | }; | |
771 | ||
3fbacffb KS |
772 | static struct device_attribute *stp_attributes[] = { |
773 | &dev_attr_ctn_id, | |
774 | &dev_attr_ctn_type, | |
775 | &dev_attr_dst_offset, | |
776 | &dev_attr_leap_seconds, | |
777 | &dev_attr_stp_online, | |
778 | &dev_attr_stratum, | |
779 | &dev_attr_time_offset, | |
780 | &dev_attr_time_zone_offset, | |
781 | &dev_attr_timing_mode, | |
782 | &dev_attr_timing_state, | |
d2fec595 MS |
783 | NULL |
784 | }; | |
785 | ||
786 | static int __init stp_init_sysfs(void) | |
787 | { | |
3fbacffb | 788 | struct device_attribute **attr; |
d2fec595 MS |
789 | int rc; |
790 | ||
3fbacffb | 791 | rc = subsys_system_register(&stp_subsys, NULL); |
d2fec595 MS |
792 | if (rc) |
793 | goto out; | |
794 | for (attr = stp_attributes; *attr; attr++) { | |
3fbacffb | 795 | rc = device_create_file(stp_subsys.dev_root, *attr); |
d2fec595 MS |
796 | if (rc) |
797 | goto out_unreg; | |
798 | } | |
799 | return 0; | |
800 | out_unreg: | |
801 | for (; attr >= stp_attributes; attr--) | |
3fbacffb KS |
802 | device_remove_file(stp_subsys.dev_root, *attr); |
803 | bus_unregister(&stp_subsys); | |
d2fec595 MS |
804 | out: |
805 | return rc; | |
806 | } | |
807 | ||
808 | device_initcall(stp_init_sysfs); |