1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Time of day based timer functions. 4 * 5 * S390 version 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) 10 * 11 * Derived from "arch/i386/kernel/time.c" 12 * Copyright (C) 1991, 1992, 1995 Linus Torvalds 13 */ 14 15 #define KMSG_COMPONENT "time" 16 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt 17 18 #include <linux/kernel_stat.h> 19 #include <linux/errno.h> 20 #include <linux/export.h> 21 #include <linux/sched.h> 22 #include <linux/sched/clock.h> 23 #include <linux/kernel.h> 24 #include <linux/param.h> 25 #include <linux/string.h> 26 #include <linux/mm.h> 27 #include <linux/interrupt.h> 28 #include <linux/cpu.h> 29 #include <linux/stop_machine.h> 30 #include <linux/time.h> 31 #include <linux/device.h> 32 #include <linux/delay.h> 33 #include <linux/init.h> 34 #include <linux/smp.h> 35 #include <linux/types.h> 36 #include <linux/profile.h> 37 #include <linux/timex.h> 38 #include <linux/notifier.h> 39 #include <linux/timekeeper_internal.h> 40 #include <linux/clockchips.h> 41 #include <linux/gfp.h> 42 #include <linux/kprobes.h> 43 #include <linux/uaccess.h> 44 #include <vdso/vsyscall.h> 45 #include <vdso/clocksource.h> 46 #include <vdso/helpers.h> 47 #include <asm/facility.h> 48 #include <asm/delay.h> 49 #include <asm/div64.h> 50 #include <asm/vdso.h> 51 #include <asm/irq.h> 52 #include <asm/irq_regs.h> 53 #include <asm/vtimer.h> 54 #include <asm/stp.h> 55 #include <asm/cio.h> 56 #include "entry.h" 57 58 union tod_clock tod_clock_base __section(".data"); 59 EXPORT_SYMBOL_GPL(tod_clock_base); 60 61 u64 clock_comparator_max = -1ULL; 62 EXPORT_SYMBOL_GPL(clock_comparator_max); 63 64 static DEFINE_PER_CPU(struct clock_event_device, comparators); 65 66 ATOMIC_NOTIFIER_HEAD(s390_epoch_delta_notifier); 67 EXPORT_SYMBOL(s390_epoch_delta_notifier); 68 69 unsigned char ptff_function_mask[16]; 70 71 static unsigned long long lpar_offset; 72 static unsigned long long initial_leap_seconds; 73 static unsigned long long tod_steering_end; 74 static long long tod_steering_delta; 75 76 /* 77 * Get time offsets with PTFF 78 */ 79 void __init time_early_init(void) 80 { 81 struct ptff_qto qto; 82 struct ptff_qui qui; 83 84 /* Initialize TOD steering parameters */ 85 tod_steering_end = tod_clock_base.tod; 86 vdso_data->arch_data.tod_steering_end = tod_steering_end; 87 88 if (!test_facility(28)) 89 return; 90 91 ptff(&ptff_function_mask, sizeof(ptff_function_mask), PTFF_QAF); 92 93 /* get LPAR offset */ 94 if (ptff_query(PTFF_QTO) && ptff(&qto, sizeof(qto), PTFF_QTO) == 0) 95 lpar_offset = qto.tod_epoch_difference; 96 97 /* get initial leap seconds */ 98 if (ptff_query(PTFF_QUI) && ptff(&qui, sizeof(qui), PTFF_QUI) == 0) 99 initial_leap_seconds = (unsigned long long) 100 ((long) qui.old_leap * 4096000000L); 101 } 102 103 /* 104 * Scheduler clock - returns current time in nanosec units. 105 */ 106 unsigned long long notrace sched_clock(void) 107 { 108 return tod_to_ns(get_tod_clock_monotonic()); 109 } 110 NOKPROBE_SYMBOL(sched_clock); 111 112 static void ext_to_timespec64(union tod_clock *clk, struct timespec64 *xt) 113 { 114 unsigned long rem, sec, nsec; 115 116 sec = clk->us; 117 rem = do_div(sec, 1000000); 118 nsec = ((clk->sus + (rem << 12)) * 125) >> 9; 119 xt->tv_sec = sec; 120 xt->tv_nsec = nsec; 121 } 122 123 void clock_comparator_work(void) 124 { 125 struct clock_event_device *cd; 126 127 S390_lowcore.clock_comparator = clock_comparator_max; 128 cd = this_cpu_ptr(&comparators); 129 cd->event_handler(cd); 130 } 131 132 static int s390_next_event(unsigned long delta, 133 struct clock_event_device *evt) 134 { 135 S390_lowcore.clock_comparator = get_tod_clock() + delta; 136 set_clock_comparator(S390_lowcore.clock_comparator); 137 return 0; 138 } 139 140 /* 141 * Set up lowcore and control register of the current cpu to 142 * enable TOD clock and clock comparator interrupts. 143 */ 144 void init_cpu_timer(void) 145 { 146 struct clock_event_device *cd; 147 int cpu; 148 149 S390_lowcore.clock_comparator = clock_comparator_max; 150 set_clock_comparator(S390_lowcore.clock_comparator); 151 152 cpu = smp_processor_id(); 153 cd = &per_cpu(comparators, cpu); 154 cd->name = "comparator"; 155 cd->features = CLOCK_EVT_FEAT_ONESHOT; 156 cd->mult = 16777; 157 cd->shift = 12; 158 cd->min_delta_ns = 1; 159 cd->min_delta_ticks = 1; 160 cd->max_delta_ns = LONG_MAX; 161 cd->max_delta_ticks = ULONG_MAX; 162 cd->rating = 400; 163 cd->cpumask = cpumask_of(cpu); 164 cd->set_next_event = s390_next_event; 165 166 clockevents_register_device(cd); 167 168 /* Enable clock comparator timer interrupt. */ 169 __ctl_set_bit(0,11); 170 171 /* Always allow the timing alert external interrupt. */ 172 __ctl_set_bit(0, 4); 173 } 174 175 static void clock_comparator_interrupt(struct ext_code ext_code, 176 unsigned int param32, 177 unsigned long param64) 178 { 179 inc_irq_stat(IRQEXT_CLK); 180 if (S390_lowcore.clock_comparator == clock_comparator_max) 181 set_clock_comparator(S390_lowcore.clock_comparator); 182 } 183 184 static void stp_timing_alert(struct stp_irq_parm *); 185 186 static void timing_alert_interrupt(struct ext_code ext_code, 187 unsigned int param32, unsigned long param64) 188 { 189 inc_irq_stat(IRQEXT_TLA); 190 if (param32 & 0x00038000) 191 stp_timing_alert((struct stp_irq_parm *) ¶m32); 192 } 193 194 static void stp_reset(void); 195 196 void read_persistent_clock64(struct timespec64 *ts) 197 { 198 union tod_clock clk; 199 u64 delta; 200 201 delta = initial_leap_seconds + TOD_UNIX_EPOCH; 202 store_tod_clock_ext(&clk); 203 clk.eitod -= delta; 204 ext_to_timespec64(&clk, ts); 205 } 206 207 void __init read_persistent_wall_and_boot_offset(struct timespec64 *wall_time, 208 struct timespec64 *boot_offset) 209 { 210 struct timespec64 boot_time; 211 union tod_clock clk; 212 u64 delta; 213 214 delta = initial_leap_seconds + TOD_UNIX_EPOCH; 215 clk = tod_clock_base; 216 clk.eitod -= delta; 217 ext_to_timespec64(&clk, &boot_time); 218 219 read_persistent_clock64(wall_time); 220 *boot_offset = timespec64_sub(*wall_time, boot_time); 221 } 222 223 static u64 read_tod_clock(struct clocksource *cs) 224 { 225 unsigned long long now, adj; 226 227 preempt_disable(); /* protect from changes to steering parameters */ 228 now = get_tod_clock(); 229 adj = tod_steering_end - now; 230 if (unlikely((s64) adj > 0)) 231 /* 232 * manually steer by 1 cycle every 2^16 cycles. This 233 * corresponds to shifting the tod delta by 15. 1s is 234 * therefore steered in ~9h. The adjust will decrease 235 * over time, until it finally reaches 0. 236 */ 237 now += (tod_steering_delta < 0) ? (adj >> 15) : -(adj >> 15); 238 preempt_enable(); 239 return now; 240 } 241 242 static struct clocksource clocksource_tod = { 243 .name = "tod", 244 .rating = 400, 245 .read = read_tod_clock, 246 .mask = CLOCKSOURCE_MASK(64), 247 .mult = 1000, 248 .shift = 12, 249 .flags = CLOCK_SOURCE_IS_CONTINUOUS, 250 .vdso_clock_mode = VDSO_CLOCKMODE_TOD, 251 }; 252 253 struct clocksource * __init clocksource_default_clock(void) 254 { 255 return &clocksource_tod; 256 } 257 258 /* 259 * Initialize the TOD clock and the CPU timer of 260 * the boot cpu. 261 */ 262 void __init time_init(void) 263 { 264 /* Reset time synchronization interfaces. */ 265 stp_reset(); 266 267 /* request the clock comparator external interrupt */ 268 if (register_external_irq(EXT_IRQ_CLK_COMP, clock_comparator_interrupt)) 269 panic("Couldn't request external interrupt 0x1004"); 270 271 /* request the timing alert external interrupt */ 272 if (register_external_irq(EXT_IRQ_TIMING_ALERT, timing_alert_interrupt)) 273 panic("Couldn't request external interrupt 0x1406"); 274 275 if (__clocksource_register(&clocksource_tod) != 0) 276 panic("Could not register TOD clock source"); 277 278 /* Enable TOD clock interrupts on the boot cpu. */ 279 init_cpu_timer(); 280 281 /* Enable cpu timer interrupts on the boot cpu. */ 282 vtime_init(); 283 } 284 285 static DEFINE_PER_CPU(atomic_t, clock_sync_word); 286 static DEFINE_MUTEX(stp_mutex); 287 static unsigned long clock_sync_flags; 288 289 #define CLOCK_SYNC_HAS_STP 0 290 #define CLOCK_SYNC_STP 1 291 #define CLOCK_SYNC_STPINFO_VALID 2 292 293 /* 294 * The get_clock function for the physical clock. It will get the current 295 * TOD clock, subtract the LPAR offset and write the result to *clock. 296 * The function returns 0 if the clock is in sync with the external time 297 * source. If the clock mode is local it will return -EOPNOTSUPP and 298 * -EAGAIN if the clock is not in sync with the external reference. 299 */ 300 int get_phys_clock(unsigned long *clock) 301 { 302 atomic_t *sw_ptr; 303 unsigned int sw0, sw1; 304 305 sw_ptr = &get_cpu_var(clock_sync_word); 306 sw0 = atomic_read(sw_ptr); 307 *clock = get_tod_clock() - lpar_offset; 308 sw1 = atomic_read(sw_ptr); 309 put_cpu_var(clock_sync_word); 310 if (sw0 == sw1 && (sw0 & 0x80000000U)) 311 /* Success: time is in sync. */ 312 return 0; 313 if (!test_bit(CLOCK_SYNC_HAS_STP, &clock_sync_flags)) 314 return -EOPNOTSUPP; 315 if (!test_bit(CLOCK_SYNC_STP, &clock_sync_flags)) 316 return -EACCES; 317 return -EAGAIN; 318 } 319 EXPORT_SYMBOL(get_phys_clock); 320 321 /* 322 * Make get_phys_clock() return -EAGAIN. 323 */ 324 static void disable_sync_clock(void *dummy) 325 { 326 atomic_t *sw_ptr = this_cpu_ptr(&clock_sync_word); 327 /* 328 * Clear the in-sync bit 2^31. All get_phys_clock calls will 329 * fail until the sync bit is turned back on. In addition 330 * increase the "sequence" counter to avoid the race of an 331 * stp event and the complete recovery against get_phys_clock. 332 */ 333 atomic_andnot(0x80000000, sw_ptr); 334 atomic_inc(sw_ptr); 335 } 336 337 /* 338 * Make get_phys_clock() return 0 again. 339 * Needs to be called from a context disabled for preemption. 340 */ 341 static void enable_sync_clock(void) 342 { 343 atomic_t *sw_ptr = this_cpu_ptr(&clock_sync_word); 344 atomic_or(0x80000000, sw_ptr); 345 } 346 347 /* 348 * Function to check if the clock is in sync. 349 */ 350 static inline int check_sync_clock(void) 351 { 352 atomic_t *sw_ptr; 353 int rc; 354 355 sw_ptr = &get_cpu_var(clock_sync_word); 356 rc = (atomic_read(sw_ptr) & 0x80000000U) != 0; 357 put_cpu_var(clock_sync_word); 358 return rc; 359 } 360 361 /* 362 * Apply clock delta to the global data structures. 363 * This is called once on the CPU that performed the clock sync. 364 */ 365 static void clock_sync_global(unsigned long long delta) 366 { 367 unsigned long now, adj; 368 struct ptff_qto qto; 369 370 /* Fixup the monotonic sched clock. */ 371 tod_clock_base.eitod += delta; 372 /* Adjust TOD steering parameters. */ 373 now = get_tod_clock(); 374 adj = tod_steering_end - now; 375 if (unlikely((s64) adj >= 0)) 376 /* Calculate how much of the old adjustment is left. */ 377 tod_steering_delta = (tod_steering_delta < 0) ? 378 -(adj >> 15) : (adj >> 15); 379 tod_steering_delta += delta; 380 if ((abs(tod_steering_delta) >> 48) != 0) 381 panic("TOD clock sync offset %lli is too large to drift\n", 382 tod_steering_delta); 383 tod_steering_end = now + (abs(tod_steering_delta) << 15); 384 vdso_data->arch_data.tod_steering_end = tod_steering_end; 385 386 /* Update LPAR offset. */ 387 if (ptff_query(PTFF_QTO) && ptff(&qto, sizeof(qto), PTFF_QTO) == 0) 388 lpar_offset = qto.tod_epoch_difference; 389 /* Call the TOD clock change notifier. */ 390 atomic_notifier_call_chain(&s390_epoch_delta_notifier, 0, &delta); 391 } 392 393 /* 394 * Apply clock delta to the per-CPU data structures of this CPU. 395 * This is called for each online CPU after the call to clock_sync_global. 396 */ 397 static void clock_sync_local(unsigned long long delta) 398 { 399 /* Add the delta to the clock comparator. */ 400 if (S390_lowcore.clock_comparator != clock_comparator_max) { 401 S390_lowcore.clock_comparator += delta; 402 set_clock_comparator(S390_lowcore.clock_comparator); 403 } 404 /* Adjust the last_update_clock time-stamp. */ 405 S390_lowcore.last_update_clock += delta; 406 } 407 408 /* Single threaded workqueue used for stp sync events */ 409 static struct workqueue_struct *time_sync_wq; 410 411 static void __init time_init_wq(void) 412 { 413 if (time_sync_wq) 414 return; 415 time_sync_wq = create_singlethread_workqueue("timesync"); 416 } 417 418 struct clock_sync_data { 419 atomic_t cpus; 420 int in_sync; 421 unsigned long long clock_delta; 422 }; 423 424 /* 425 * Server Time Protocol (STP) code. 426 */ 427 static bool stp_online; 428 static struct stp_sstpi stp_info; 429 static void *stp_page; 430 431 static void stp_work_fn(struct work_struct *work); 432 static DECLARE_WORK(stp_work, stp_work_fn); 433 static struct timer_list stp_timer; 434 435 static int __init early_parse_stp(char *p) 436 { 437 return kstrtobool(p, &stp_online); 438 } 439 early_param("stp", early_parse_stp); 440 441 /* 442 * Reset STP attachment. 443 */ 444 static void __init stp_reset(void) 445 { 446 int rc; 447 448 stp_page = (void *) get_zeroed_page(GFP_ATOMIC); 449 rc = chsc_sstpc(stp_page, STP_OP_CTRL, 0x0000, NULL); 450 if (rc == 0) 451 set_bit(CLOCK_SYNC_HAS_STP, &clock_sync_flags); 452 else if (stp_online) { 453 pr_warn("The real or virtual hardware system does not provide an STP interface\n"); 454 free_page((unsigned long) stp_page); 455 stp_page = NULL; 456 stp_online = false; 457 } 458 } 459 460 static void stp_timeout(struct timer_list *unused) 461 { 462 queue_work(time_sync_wq, &stp_work); 463 } 464 465 static int __init stp_init(void) 466 { 467 if (!test_bit(CLOCK_SYNC_HAS_STP, &clock_sync_flags)) 468 return 0; 469 timer_setup(&stp_timer, stp_timeout, 0); 470 time_init_wq(); 471 if (!stp_online) 472 return 0; 473 queue_work(time_sync_wq, &stp_work); 474 return 0; 475 } 476 477 arch_initcall(stp_init); 478 479 /* 480 * STP timing alert. There are three causes: 481 * 1) timing status change 482 * 2) link availability change 483 * 3) time control parameter change 484 * In all three cases we are only interested in the clock source state. 485 * If a STP clock source is now available use it. 486 */ 487 static void stp_timing_alert(struct stp_irq_parm *intparm) 488 { 489 if (intparm->tsc || intparm->lac || intparm->tcpc) 490 queue_work(time_sync_wq, &stp_work); 491 } 492 493 /* 494 * STP sync check machine check. This is called when the timing state 495 * changes from the synchronized state to the unsynchronized state. 496 * After a STP sync check the clock is not in sync. The machine check 497 * is broadcasted to all cpus at the same time. 498 */ 499 int stp_sync_check(void) 500 { 501 disable_sync_clock(NULL); 502 return 1; 503 } 504 505 /* 506 * STP island condition machine check. This is called when an attached 507 * server attempts to communicate over an STP link and the servers 508 * have matching CTN ids and have a valid stratum-1 configuration 509 * but the configurations do not match. 510 */ 511 int stp_island_check(void) 512 { 513 disable_sync_clock(NULL); 514 return 1; 515 } 516 517 void stp_queue_work(void) 518 { 519 queue_work(time_sync_wq, &stp_work); 520 } 521 522 static int __store_stpinfo(void) 523 { 524 int rc = chsc_sstpi(stp_page, &stp_info, sizeof(struct stp_sstpi)); 525 526 if (rc) 527 clear_bit(CLOCK_SYNC_STPINFO_VALID, &clock_sync_flags); 528 else 529 set_bit(CLOCK_SYNC_STPINFO_VALID, &clock_sync_flags); 530 return rc; 531 } 532 533 static int stpinfo_valid(void) 534 { 535 return stp_online && test_bit(CLOCK_SYNC_STPINFO_VALID, &clock_sync_flags); 536 } 537 538 static int stp_sync_clock(void *data) 539 { 540 struct clock_sync_data *sync = data; 541 unsigned long long clock_delta, flags; 542 static int first; 543 int rc; 544 545 enable_sync_clock(); 546 if (xchg(&first, 1) == 0) { 547 /* Wait until all other cpus entered the sync function. */ 548 while (atomic_read(&sync->cpus) != 0) 549 cpu_relax(); 550 rc = 0; 551 if (stp_info.todoff[0] || stp_info.todoff[1] || 552 stp_info.todoff[2] || stp_info.todoff[3] || 553 stp_info.tmd != 2) { 554 flags = vdso_update_begin(); 555 rc = chsc_sstpc(stp_page, STP_OP_SYNC, 0, 556 &clock_delta); 557 if (rc == 0) { 558 sync->clock_delta = clock_delta; 559 clock_sync_global(clock_delta); 560 rc = __store_stpinfo(); 561 if (rc == 0 && stp_info.tmd != 2) 562 rc = -EAGAIN; 563 } 564 vdso_update_end(flags); 565 } 566 sync->in_sync = rc ? -EAGAIN : 1; 567 xchg(&first, 0); 568 } else { 569 /* Slave */ 570 atomic_dec(&sync->cpus); 571 /* Wait for in_sync to be set. */ 572 while (READ_ONCE(sync->in_sync) == 0) 573 __udelay(1); 574 } 575 if (sync->in_sync != 1) 576 /* Didn't work. Clear per-cpu in sync bit again. */ 577 disable_sync_clock(NULL); 578 /* Apply clock delta to per-CPU fields of this CPU. */ 579 clock_sync_local(sync->clock_delta); 580 581 return 0; 582 } 583 584 static int stp_clear_leap(void) 585 { 586 struct __kernel_timex txc; 587 int ret; 588 589 memset(&txc, 0, sizeof(txc)); 590 591 ret = do_adjtimex(&txc); 592 if (ret < 0) 593 return ret; 594 595 txc.modes = ADJ_STATUS; 596 txc.status &= ~(STA_INS|STA_DEL); 597 return do_adjtimex(&txc); 598 } 599 600 static void stp_check_leap(void) 601 { 602 struct stp_stzi stzi; 603 struct stp_lsoib *lsoib = &stzi.lsoib; 604 struct __kernel_timex txc; 605 int64_t timediff; 606 int leapdiff, ret; 607 608 if (!stp_info.lu || !check_sync_clock()) { 609 /* 610 * Either a scheduled leap second was removed by the operator, 611 * or STP is out of sync. In both cases, clear the leap second 612 * kernel flags. 613 */ 614 if (stp_clear_leap() < 0) 615 pr_err("failed to clear leap second flags\n"); 616 return; 617 } 618 619 if (chsc_stzi(stp_page, &stzi, sizeof(stzi))) { 620 pr_err("stzi failed\n"); 621 return; 622 } 623 624 timediff = tod_to_ns(lsoib->nlsout - get_tod_clock()) / NSEC_PER_SEC; 625 leapdiff = lsoib->nlso - lsoib->also; 626 627 if (leapdiff != 1 && leapdiff != -1) { 628 pr_err("Cannot schedule %d leap seconds\n", leapdiff); 629 return; 630 } 631 632 if (timediff < 0) { 633 if (stp_clear_leap() < 0) 634 pr_err("failed to clear leap second flags\n"); 635 } else if (timediff < 7200) { 636 memset(&txc, 0, sizeof(txc)); 637 ret = do_adjtimex(&txc); 638 if (ret < 0) 639 return; 640 641 txc.modes = ADJ_STATUS; 642 if (leapdiff > 0) 643 txc.status |= STA_INS; 644 else 645 txc.status |= STA_DEL; 646 ret = do_adjtimex(&txc); 647 if (ret < 0) 648 pr_err("failed to set leap second flags\n"); 649 /* arm Timer to clear leap second flags */ 650 mod_timer(&stp_timer, jiffies + msecs_to_jiffies(14400 * MSEC_PER_SEC)); 651 } else { 652 /* The day the leap second is scheduled for hasn't been reached. Retry 653 * in one hour. 654 */ 655 mod_timer(&stp_timer, jiffies + msecs_to_jiffies(3600 * MSEC_PER_SEC)); 656 } 657 } 658 659 /* 660 * STP work. Check for the STP state and take over the clock 661 * synchronization if the STP clock source is usable. 662 */ 663 static void stp_work_fn(struct work_struct *work) 664 { 665 struct clock_sync_data stp_sync; 666 int rc; 667 668 /* prevent multiple execution. */ 669 mutex_lock(&stp_mutex); 670 671 if (!stp_online) { 672 chsc_sstpc(stp_page, STP_OP_CTRL, 0x0000, NULL); 673 del_timer_sync(&stp_timer); 674 goto out_unlock; 675 } 676 677 rc = chsc_sstpc(stp_page, STP_OP_CTRL, 0xf0e0, NULL); 678 if (rc) 679 goto out_unlock; 680 681 rc = __store_stpinfo(); 682 if (rc || stp_info.c == 0) 683 goto out_unlock; 684 685 /* Skip synchronization if the clock is already in sync. */ 686 if (!check_sync_clock()) { 687 memset(&stp_sync, 0, sizeof(stp_sync)); 688 cpus_read_lock(); 689 atomic_set(&stp_sync.cpus, num_online_cpus() - 1); 690 stop_machine_cpuslocked(stp_sync_clock, &stp_sync, cpu_online_mask); 691 cpus_read_unlock(); 692 } 693 694 if (!check_sync_clock()) 695 /* 696 * There is a usable clock but the synchonization failed. 697 * Retry after a second. 698 */ 699 mod_timer(&stp_timer, jiffies + msecs_to_jiffies(MSEC_PER_SEC)); 700 else if (stp_info.lu) 701 stp_check_leap(); 702 703 out_unlock: 704 mutex_unlock(&stp_mutex); 705 } 706 707 /* 708 * STP subsys sysfs interface functions 709 */ 710 static struct bus_type stp_subsys = { 711 .name = "stp", 712 .dev_name = "stp", 713 }; 714 715 static ssize_t ctn_id_show(struct device *dev, 716 struct device_attribute *attr, 717 char *buf) 718 { 719 ssize_t ret = -ENODATA; 720 721 mutex_lock(&stp_mutex); 722 if (stpinfo_valid()) 723 ret = sprintf(buf, "%016llx\n", 724 *(unsigned long long *) stp_info.ctnid); 725 mutex_unlock(&stp_mutex); 726 return ret; 727 } 728 729 static DEVICE_ATTR_RO(ctn_id); 730 731 static ssize_t ctn_type_show(struct device *dev, 732 struct device_attribute *attr, 733 char *buf) 734 { 735 ssize_t ret = -ENODATA; 736 737 mutex_lock(&stp_mutex); 738 if (stpinfo_valid()) 739 ret = sprintf(buf, "%i\n", stp_info.ctn); 740 mutex_unlock(&stp_mutex); 741 return ret; 742 } 743 744 static DEVICE_ATTR_RO(ctn_type); 745 746 static ssize_t dst_offset_show(struct device *dev, 747 struct device_attribute *attr, 748 char *buf) 749 { 750 ssize_t ret = -ENODATA; 751 752 mutex_lock(&stp_mutex); 753 if (stpinfo_valid() && (stp_info.vbits & 0x2000)) 754 ret = sprintf(buf, "%i\n", (int)(s16) stp_info.dsto); 755 mutex_unlock(&stp_mutex); 756 return ret; 757 } 758 759 static DEVICE_ATTR_RO(dst_offset); 760 761 static ssize_t leap_seconds_show(struct device *dev, 762 struct device_attribute *attr, 763 char *buf) 764 { 765 ssize_t ret = -ENODATA; 766 767 mutex_lock(&stp_mutex); 768 if (stpinfo_valid() && (stp_info.vbits & 0x8000)) 769 ret = sprintf(buf, "%i\n", (int)(s16) stp_info.leaps); 770 mutex_unlock(&stp_mutex); 771 return ret; 772 } 773 774 static DEVICE_ATTR_RO(leap_seconds); 775 776 static ssize_t leap_seconds_scheduled_show(struct device *dev, 777 struct device_attribute *attr, 778 char *buf) 779 { 780 struct stp_stzi stzi; 781 ssize_t ret; 782 783 mutex_lock(&stp_mutex); 784 if (!stpinfo_valid() || !(stp_info.vbits & 0x8000) || !stp_info.lu) { 785 mutex_unlock(&stp_mutex); 786 return -ENODATA; 787 } 788 789 ret = chsc_stzi(stp_page, &stzi, sizeof(stzi)); 790 mutex_unlock(&stp_mutex); 791 if (ret < 0) 792 return ret; 793 794 if (!stzi.lsoib.p) 795 return sprintf(buf, "0,0\n"); 796 797 return sprintf(buf, "%llu,%d\n", 798 tod_to_ns(stzi.lsoib.nlsout - TOD_UNIX_EPOCH) / NSEC_PER_SEC, 799 stzi.lsoib.nlso - stzi.lsoib.also); 800 } 801 802 static DEVICE_ATTR_RO(leap_seconds_scheduled); 803 804 static ssize_t stratum_show(struct device *dev, 805 struct device_attribute *attr, 806 char *buf) 807 { 808 ssize_t ret = -ENODATA; 809 810 mutex_lock(&stp_mutex); 811 if (stpinfo_valid()) 812 ret = sprintf(buf, "%i\n", (int)(s16) stp_info.stratum); 813 mutex_unlock(&stp_mutex); 814 return ret; 815 } 816 817 static DEVICE_ATTR_RO(stratum); 818 819 static ssize_t time_offset_show(struct device *dev, 820 struct device_attribute *attr, 821 char *buf) 822 { 823 ssize_t ret = -ENODATA; 824 825 mutex_lock(&stp_mutex); 826 if (stpinfo_valid() && (stp_info.vbits & 0x0800)) 827 ret = sprintf(buf, "%i\n", (int) stp_info.tto); 828 mutex_unlock(&stp_mutex); 829 return ret; 830 } 831 832 static DEVICE_ATTR_RO(time_offset); 833 834 static ssize_t time_zone_offset_show(struct device *dev, 835 struct device_attribute *attr, 836 char *buf) 837 { 838 ssize_t ret = -ENODATA; 839 840 mutex_lock(&stp_mutex); 841 if (stpinfo_valid() && (stp_info.vbits & 0x4000)) 842 ret = sprintf(buf, "%i\n", (int)(s16) stp_info.tzo); 843 mutex_unlock(&stp_mutex); 844 return ret; 845 } 846 847 static DEVICE_ATTR_RO(time_zone_offset); 848 849 static ssize_t timing_mode_show(struct device *dev, 850 struct device_attribute *attr, 851 char *buf) 852 { 853 ssize_t ret = -ENODATA; 854 855 mutex_lock(&stp_mutex); 856 if (stpinfo_valid()) 857 ret = sprintf(buf, "%i\n", stp_info.tmd); 858 mutex_unlock(&stp_mutex); 859 return ret; 860 } 861 862 static DEVICE_ATTR_RO(timing_mode); 863 864 static ssize_t timing_state_show(struct device *dev, 865 struct device_attribute *attr, 866 char *buf) 867 { 868 ssize_t ret = -ENODATA; 869 870 mutex_lock(&stp_mutex); 871 if (stpinfo_valid()) 872 ret = sprintf(buf, "%i\n", stp_info.tst); 873 mutex_unlock(&stp_mutex); 874 return ret; 875 } 876 877 static DEVICE_ATTR_RO(timing_state); 878 879 static ssize_t online_show(struct device *dev, 880 struct device_attribute *attr, 881 char *buf) 882 { 883 return sprintf(buf, "%i\n", stp_online); 884 } 885 886 static ssize_t online_store(struct device *dev, 887 struct device_attribute *attr, 888 const char *buf, size_t count) 889 { 890 unsigned int value; 891 892 value = simple_strtoul(buf, NULL, 0); 893 if (value != 0 && value != 1) 894 return -EINVAL; 895 if (!test_bit(CLOCK_SYNC_HAS_STP, &clock_sync_flags)) 896 return -EOPNOTSUPP; 897 mutex_lock(&stp_mutex); 898 stp_online = value; 899 if (stp_online) 900 set_bit(CLOCK_SYNC_STP, &clock_sync_flags); 901 else 902 clear_bit(CLOCK_SYNC_STP, &clock_sync_flags); 903 queue_work(time_sync_wq, &stp_work); 904 mutex_unlock(&stp_mutex); 905 return count; 906 } 907 908 /* 909 * Can't use DEVICE_ATTR because the attribute should be named 910 * stp/online but dev_attr_online already exists in this file .. 911 */ 912 static DEVICE_ATTR_RW(online); 913 914 static struct attribute *stp_dev_attrs[] = { 915 &dev_attr_ctn_id.attr, 916 &dev_attr_ctn_type.attr, 917 &dev_attr_dst_offset.attr, 918 &dev_attr_leap_seconds.attr, 919 &dev_attr_online.attr, 920 &dev_attr_leap_seconds_scheduled.attr, 921 &dev_attr_stratum.attr, 922 &dev_attr_time_offset.attr, 923 &dev_attr_time_zone_offset.attr, 924 &dev_attr_timing_mode.attr, 925 &dev_attr_timing_state.attr, 926 NULL 927 }; 928 ATTRIBUTE_GROUPS(stp_dev); 929 930 static int __init stp_init_sysfs(void) 931 { 932 return subsys_system_register(&stp_subsys, stp_dev_groups); 933 } 934 935 device_initcall(stp_init_sysfs); 936