1 /* 2 * arch/s390/kernel/time.c 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/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> 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 <asm/uaccess.h> 40 #include <asm/delay.h> 41 #include <asm/s390_ext.h> 42 #include <asm/div64.h> 43 #include <asm/vdso.h> 44 #include <asm/irq.h> 45 #include <asm/irq_regs.h> 46 #include <asm/timer.h> 47 #include <asm/etr.h> 48 #include <asm/cio.h> 49 50 /* change this if you have some constant time drift */ 51 #define USECS_PER_JIFFY ((unsigned long) 1000000/HZ) 52 #define CLK_TICKS_PER_JIFFY ((unsigned long) USECS_PER_JIFFY << 12) 53 54 u64 sched_clock_base_cc = -1; /* Force to data section. */ 55 EXPORT_SYMBOL_GPL(sched_clock_base_cc); 56 57 static DEFINE_PER_CPU(struct clock_event_device, comparators); 58 59 /* 60 * Scheduler clock - returns current time in nanosec units. 61 */ 62 unsigned long long notrace sched_clock(void) 63 { 64 return (get_clock_monotonic() * 125) >> 9; 65 } 66 67 /* 68 * Monotonic_clock - returns # of nanoseconds passed since time_init() 69 */ 70 unsigned long long monotonic_clock(void) 71 { 72 return sched_clock(); 73 } 74 EXPORT_SYMBOL(monotonic_clock); 75 76 void tod_to_timeval(__u64 todval, struct timespec *xtime) 77 { 78 unsigned long long sec; 79 80 sec = todval >> 12; 81 do_div(sec, 1000000); 82 xtime->tv_sec = sec; 83 todval -= (sec * 1000000) << 12; 84 xtime->tv_nsec = ((todval * 1000) >> 12); 85 } 86 EXPORT_SYMBOL(tod_to_timeval); 87 88 void clock_comparator_work(void) 89 { 90 struct clock_event_device *cd; 91 92 S390_lowcore.clock_comparator = -1ULL; 93 set_clock_comparator(S390_lowcore.clock_comparator); 94 cd = &__get_cpu_var(comparators); 95 cd->event_handler(cd); 96 } 97 98 /* 99 * Fixup the clock comparator. 100 */ 101 static void fixup_clock_comparator(unsigned long long delta) 102 { 103 /* If nobody is waiting there's nothing to fix. */ 104 if (S390_lowcore.clock_comparator == -1ULL) 105 return; 106 S390_lowcore.clock_comparator += delta; 107 set_clock_comparator(S390_lowcore.clock_comparator); 108 } 109 110 static int s390_next_event(unsigned long delta, 111 struct clock_event_device *evt) 112 { 113 S390_lowcore.clock_comparator = get_clock() + delta; 114 set_clock_comparator(S390_lowcore.clock_comparator); 115 return 0; 116 } 117 118 static void s390_set_mode(enum clock_event_mode mode, 119 struct clock_event_device *evt) 120 { 121 } 122 123 /* 124 * Set up lowcore and control register of the current cpu to 125 * enable TOD clock and clock comparator interrupts. 126 */ 127 void init_cpu_timer(void) 128 { 129 struct clock_event_device *cd; 130 int cpu; 131 132 S390_lowcore.clock_comparator = -1ULL; 133 set_clock_comparator(S390_lowcore.clock_comparator); 134 135 cpu = smp_processor_id(); 136 cd = &per_cpu(comparators, cpu); 137 cd->name = "comparator"; 138 cd->features = CLOCK_EVT_FEAT_ONESHOT; 139 cd->mult = 16777; 140 cd->shift = 12; 141 cd->min_delta_ns = 1; 142 cd->max_delta_ns = LONG_MAX; 143 cd->rating = 400; 144 cd->cpumask = cpumask_of(cpu); 145 cd->set_next_event = s390_next_event; 146 cd->set_mode = s390_set_mode; 147 148 clockevents_register_device(cd); 149 150 /* Enable clock comparator timer interrupt. */ 151 __ctl_set_bit(0,11); 152 153 /* Always allow the timing alert external interrupt. */ 154 __ctl_set_bit(0, 4); 155 } 156 157 static void clock_comparator_interrupt(__u16 code) 158 { 159 if (S390_lowcore.clock_comparator == -1ULL) 160 set_clock_comparator(S390_lowcore.clock_comparator); 161 } 162 163 static void etr_timing_alert(struct etr_irq_parm *); 164 static void stp_timing_alert(struct stp_irq_parm *); 165 166 static void timing_alert_interrupt(__u16 code) 167 { 168 if (S390_lowcore.ext_params & 0x00c40000) 169 etr_timing_alert((struct etr_irq_parm *) 170 &S390_lowcore.ext_params); 171 if (S390_lowcore.ext_params & 0x00038000) 172 stp_timing_alert((struct stp_irq_parm *) 173 &S390_lowcore.ext_params); 174 } 175 176 static void etr_reset(void); 177 static void stp_reset(void); 178 179 void read_persistent_clock(struct timespec *ts) 180 { 181 tod_to_timeval(get_clock() - TOD_UNIX_EPOCH, ts); 182 } 183 184 void read_boot_clock(struct timespec *ts) 185 { 186 tod_to_timeval(sched_clock_base_cc - TOD_UNIX_EPOCH, ts); 187 } 188 189 static cycle_t read_tod_clock(struct clocksource *cs) 190 { 191 return get_clock(); 192 } 193 194 static struct clocksource clocksource_tod = { 195 .name = "tod", 196 .rating = 400, 197 .read = read_tod_clock, 198 .mask = -1ULL, 199 .mult = 1000, 200 .shift = 12, 201 .flags = CLOCK_SOURCE_IS_CONTINUOUS, 202 }; 203 204 struct clocksource * __init clocksource_default_clock(void) 205 { 206 return &clocksource_tod; 207 } 208 209 void update_vsyscall(struct timespec *wall_time, struct clocksource *clock, 210 u32 mult) 211 { 212 if (clock != &clocksource_tod) 213 return; 214 215 /* Make userspace gettimeofday spin until we're done. */ 216 ++vdso_data->tb_update_count; 217 smp_wmb(); 218 vdso_data->xtime_tod_stamp = clock->cycle_last; 219 vdso_data->xtime_clock_sec = xtime.tv_sec; 220 vdso_data->xtime_clock_nsec = xtime.tv_nsec; 221 vdso_data->wtom_clock_sec = wall_to_monotonic.tv_sec; 222 vdso_data->wtom_clock_nsec = wall_to_monotonic.tv_nsec; 223 smp_wmb(); 224 ++vdso_data->tb_update_count; 225 } 226 227 extern struct timezone sys_tz; 228 229 void update_vsyscall_tz(void) 230 { 231 /* Make userspace gettimeofday spin until we're done. */ 232 ++vdso_data->tb_update_count; 233 smp_wmb(); 234 vdso_data->tz_minuteswest = sys_tz.tz_minuteswest; 235 vdso_data->tz_dsttime = sys_tz.tz_dsttime; 236 smp_wmb(); 237 ++vdso_data->tb_update_count; 238 } 239 240 /* 241 * Initialize the TOD clock and the CPU timer of 242 * the boot cpu. 243 */ 244 void __init time_init(void) 245 { 246 /* Reset time synchronization interfaces. */ 247 etr_reset(); 248 stp_reset(); 249 250 /* request the clock comparator external interrupt */ 251 if (register_external_interrupt(0x1004, clock_comparator_interrupt)) 252 panic("Couldn't request external interrupt 0x1004"); 253 254 /* request the timing alert external interrupt */ 255 if (register_external_interrupt(0x1406, timing_alert_interrupt)) 256 panic("Couldn't request external interrupt 0x1406"); 257 258 if (clocksource_register(&clocksource_tod) != 0) 259 panic("Could not register TOD clock source"); 260 261 /* Enable TOD clock interrupts on the boot cpu. */ 262 init_cpu_timer(); 263 264 /* Enable cpu timer interrupts on the boot cpu. */ 265 vtime_init(); 266 } 267 268 /* 269 * The time is "clock". old is what we think the time is. 270 * Adjust the value by a multiple of jiffies and add the delta to ntp. 271 * "delay" is an approximation how long the synchronization took. If 272 * the time correction is positive, then "delay" is subtracted from 273 * the time difference and only the remaining part is passed to ntp. 274 */ 275 static unsigned long long adjust_time(unsigned long long old, 276 unsigned long long clock, 277 unsigned long long delay) 278 { 279 unsigned long long delta, ticks; 280 struct timex adjust; 281 282 if (clock > old) { 283 /* It is later than we thought. */ 284 delta = ticks = clock - old; 285 delta = ticks = (delta < delay) ? 0 : delta - delay; 286 delta -= do_div(ticks, CLK_TICKS_PER_JIFFY); 287 adjust.offset = ticks * (1000000 / HZ); 288 } else { 289 /* It is earlier than we thought. */ 290 delta = ticks = old - clock; 291 delta -= do_div(ticks, CLK_TICKS_PER_JIFFY); 292 delta = -delta; 293 adjust.offset = -ticks * (1000000 / HZ); 294 } 295 sched_clock_base_cc += delta; 296 if (adjust.offset != 0) { 297 pr_notice("The ETR interface has adjusted the clock " 298 "by %li microseconds\n", adjust.offset); 299 adjust.modes = ADJ_OFFSET_SINGLESHOT; 300 do_adjtimex(&adjust); 301 } 302 return delta; 303 } 304 305 static DEFINE_PER_CPU(atomic_t, clock_sync_word); 306 static DEFINE_MUTEX(clock_sync_mutex); 307 static unsigned long clock_sync_flags; 308 309 #define CLOCK_SYNC_HAS_ETR 0 310 #define CLOCK_SYNC_HAS_STP 1 311 #define CLOCK_SYNC_ETR 2 312 #define CLOCK_SYNC_STP 3 313 314 /* 315 * The synchronous get_clock function. It will write the current clock 316 * value to the clock pointer and return 0 if the clock is in sync with 317 * the external time source. If the clock mode is local it will return 318 * -ENOSYS and -EAGAIN if the clock is not in sync with the external 319 * reference. 320 */ 321 int get_sync_clock(unsigned long long *clock) 322 { 323 atomic_t *sw_ptr; 324 unsigned int sw0, sw1; 325 326 sw_ptr = &get_cpu_var(clock_sync_word); 327 sw0 = atomic_read(sw_ptr); 328 *clock = get_clock(); 329 sw1 = atomic_read(sw_ptr); 330 put_cpu_var(clock_sync_word); 331 if (sw0 == sw1 && (sw0 & 0x80000000U)) 332 /* Success: time is in sync. */ 333 return 0; 334 if (!test_bit(CLOCK_SYNC_HAS_ETR, &clock_sync_flags) && 335 !test_bit(CLOCK_SYNC_HAS_STP, &clock_sync_flags)) 336 return -ENOSYS; 337 if (!test_bit(CLOCK_SYNC_ETR, &clock_sync_flags) && 338 !test_bit(CLOCK_SYNC_STP, &clock_sync_flags)) 339 return -EACCES; 340 return -EAGAIN; 341 } 342 EXPORT_SYMBOL(get_sync_clock); 343 344 /* 345 * Make get_sync_clock return -EAGAIN. 346 */ 347 static void disable_sync_clock(void *dummy) 348 { 349 atomic_t *sw_ptr = &__get_cpu_var(clock_sync_word); 350 /* 351 * Clear the in-sync bit 2^31. All get_sync_clock calls will 352 * fail until the sync bit is turned back on. In addition 353 * increase the "sequence" counter to avoid the race of an 354 * etr event and the complete recovery against get_sync_clock. 355 */ 356 atomic_clear_mask(0x80000000, sw_ptr); 357 atomic_inc(sw_ptr); 358 } 359 360 /* 361 * Make get_sync_clock return 0 again. 362 * Needs to be called from a context disabled for preemption. 363 */ 364 static void enable_sync_clock(void) 365 { 366 atomic_t *sw_ptr = &__get_cpu_var(clock_sync_word); 367 atomic_set_mask(0x80000000, sw_ptr); 368 } 369 370 /* 371 * Function to check if the clock is in sync. 372 */ 373 static inline int check_sync_clock(void) 374 { 375 atomic_t *sw_ptr; 376 int rc; 377 378 sw_ptr = &get_cpu_var(clock_sync_word); 379 rc = (atomic_read(sw_ptr) & 0x80000000U) != 0; 380 put_cpu_var(clock_sync_word); 381 return rc; 382 } 383 384 /* Single threaded workqueue used for etr and stp sync events */ 385 static struct workqueue_struct *time_sync_wq; 386 387 static void __init time_init_wq(void) 388 { 389 if (time_sync_wq) 390 return; 391 time_sync_wq = create_singlethread_workqueue("timesync"); 392 stop_machine_create(); 393 } 394 395 /* 396 * External Time Reference (ETR) code. 397 */ 398 static int etr_port0_online; 399 static int etr_port1_online; 400 static int etr_steai_available; 401 402 static int __init early_parse_etr(char *p) 403 { 404 if (strncmp(p, "off", 3) == 0) 405 etr_port0_online = etr_port1_online = 0; 406 else if (strncmp(p, "port0", 5) == 0) 407 etr_port0_online = 1; 408 else if (strncmp(p, "port1", 5) == 0) 409 etr_port1_online = 1; 410 else if (strncmp(p, "on", 2) == 0) 411 etr_port0_online = etr_port1_online = 1; 412 return 0; 413 } 414 early_param("etr", early_parse_etr); 415 416 enum etr_event { 417 ETR_EVENT_PORT0_CHANGE, 418 ETR_EVENT_PORT1_CHANGE, 419 ETR_EVENT_PORT_ALERT, 420 ETR_EVENT_SYNC_CHECK, 421 ETR_EVENT_SWITCH_LOCAL, 422 ETR_EVENT_UPDATE, 423 }; 424 425 /* 426 * Valid bit combinations of the eacr register are (x = don't care): 427 * e0 e1 dp p0 p1 ea es sl 428 * 0 0 x 0 0 0 0 0 initial, disabled state 429 * 0 0 x 0 1 1 0 0 port 1 online 430 * 0 0 x 1 0 1 0 0 port 0 online 431 * 0 0 x 1 1 1 0 0 both ports online 432 * 0 1 x 0 1 1 0 0 port 1 online and usable, ETR or PPS mode 433 * 0 1 x 0 1 1 0 1 port 1 online, usable and ETR mode 434 * 0 1 x 0 1 1 1 0 port 1 online, usable, PPS mode, in-sync 435 * 0 1 x 0 1 1 1 1 port 1 online, usable, ETR mode, in-sync 436 * 0 1 x 1 1 1 0 0 both ports online, port 1 usable 437 * 0 1 x 1 1 1 1 0 both ports online, port 1 usable, PPS mode, in-sync 438 * 0 1 x 1 1 1 1 1 both ports online, port 1 usable, ETR mode, in-sync 439 * 1 0 x 1 0 1 0 0 port 0 online and usable, ETR or PPS mode 440 * 1 0 x 1 0 1 0 1 port 0 online, usable and ETR mode 441 * 1 0 x 1 0 1 1 0 port 0 online, usable, PPS mode, in-sync 442 * 1 0 x 1 0 1 1 1 port 0 online, usable, ETR mode, in-sync 443 * 1 0 x 1 1 1 0 0 both ports online, port 0 usable 444 * 1 0 x 1 1 1 1 0 both ports online, port 0 usable, PPS mode, in-sync 445 * 1 0 x 1 1 1 1 1 both ports online, port 0 usable, ETR mode, in-sync 446 * 1 1 x 1 1 1 1 0 both ports online & usable, ETR, in-sync 447 * 1 1 x 1 1 1 1 1 both ports online & usable, ETR, in-sync 448 */ 449 static struct etr_eacr etr_eacr; 450 static u64 etr_tolec; /* time of last eacr update */ 451 static struct etr_aib etr_port0; 452 static int etr_port0_uptodate; 453 static struct etr_aib etr_port1; 454 static int etr_port1_uptodate; 455 static unsigned long etr_events; 456 static struct timer_list etr_timer; 457 458 static void etr_timeout(unsigned long dummy); 459 static void etr_work_fn(struct work_struct *work); 460 static DEFINE_MUTEX(etr_work_mutex); 461 static DECLARE_WORK(etr_work, etr_work_fn); 462 463 /* 464 * Reset ETR attachment. 465 */ 466 static void etr_reset(void) 467 { 468 etr_eacr = (struct etr_eacr) { 469 .e0 = 0, .e1 = 0, ._pad0 = 4, .dp = 0, 470 .p0 = 0, .p1 = 0, ._pad1 = 0, .ea = 0, 471 .es = 0, .sl = 0 }; 472 if (etr_setr(&etr_eacr) == 0) { 473 etr_tolec = get_clock(); 474 set_bit(CLOCK_SYNC_HAS_ETR, &clock_sync_flags); 475 if (etr_port0_online && etr_port1_online) 476 set_bit(CLOCK_SYNC_ETR, &clock_sync_flags); 477 } else if (etr_port0_online || etr_port1_online) { 478 pr_warning("The real or virtual hardware system does " 479 "not provide an ETR interface\n"); 480 etr_port0_online = etr_port1_online = 0; 481 } 482 } 483 484 static int __init etr_init(void) 485 { 486 struct etr_aib aib; 487 488 if (!test_bit(CLOCK_SYNC_HAS_ETR, &clock_sync_flags)) 489 return 0; 490 time_init_wq(); 491 /* Check if this machine has the steai instruction. */ 492 if (etr_steai(&aib, ETR_STEAI_STEPPING_PORT) == 0) 493 etr_steai_available = 1; 494 setup_timer(&etr_timer, etr_timeout, 0UL); 495 if (etr_port0_online) { 496 set_bit(ETR_EVENT_PORT0_CHANGE, &etr_events); 497 queue_work(time_sync_wq, &etr_work); 498 } 499 if (etr_port1_online) { 500 set_bit(ETR_EVENT_PORT1_CHANGE, &etr_events); 501 queue_work(time_sync_wq, &etr_work); 502 } 503 return 0; 504 } 505 506 arch_initcall(etr_init); 507 508 /* 509 * Two sorts of ETR machine checks. The architecture reads: 510 * "When a machine-check niterruption occurs and if a switch-to-local or 511 * ETR-sync-check interrupt request is pending but disabled, this pending 512 * disabled interruption request is indicated and is cleared". 513 * Which means that we can get etr_switch_to_local events from the machine 514 * check handler although the interruption condition is disabled. Lovely.. 515 */ 516 517 /* 518 * Switch to local machine check. This is called when the last usable 519 * ETR port goes inactive. After switch to local the clock is not in sync. 520 */ 521 void etr_switch_to_local(void) 522 { 523 if (!etr_eacr.sl) 524 return; 525 disable_sync_clock(NULL); 526 set_bit(ETR_EVENT_SWITCH_LOCAL, &etr_events); 527 queue_work(time_sync_wq, &etr_work); 528 } 529 530 /* 531 * ETR sync check machine check. This is called when the ETR OTE and the 532 * local clock OTE are farther apart than the ETR sync check tolerance. 533 * After a ETR sync check the clock is not in sync. The machine check 534 * is broadcasted to all cpus at the same time. 535 */ 536 void etr_sync_check(void) 537 { 538 if (!etr_eacr.es) 539 return; 540 disable_sync_clock(NULL); 541 set_bit(ETR_EVENT_SYNC_CHECK, &etr_events); 542 queue_work(time_sync_wq, &etr_work); 543 } 544 545 /* 546 * ETR timing alert. There are two causes: 547 * 1) port state change, check the usability of the port 548 * 2) port alert, one of the ETR-data-validity bits (v1-v2 bits of the 549 * sldr-status word) or ETR-data word 1 (edf1) or ETR-data word 3 (edf3) 550 * or ETR-data word 4 (edf4) has changed. 551 */ 552 static void etr_timing_alert(struct etr_irq_parm *intparm) 553 { 554 if (intparm->pc0) 555 /* ETR port 0 state change. */ 556 set_bit(ETR_EVENT_PORT0_CHANGE, &etr_events); 557 if (intparm->pc1) 558 /* ETR port 1 state change. */ 559 set_bit(ETR_EVENT_PORT1_CHANGE, &etr_events); 560 if (intparm->eai) 561 /* 562 * ETR port alert on either port 0, 1 or both. 563 * Both ports are not up-to-date now. 564 */ 565 set_bit(ETR_EVENT_PORT_ALERT, &etr_events); 566 queue_work(time_sync_wq, &etr_work); 567 } 568 569 static void etr_timeout(unsigned long dummy) 570 { 571 set_bit(ETR_EVENT_UPDATE, &etr_events); 572 queue_work(time_sync_wq, &etr_work); 573 } 574 575 /* 576 * Check if the etr mode is pss. 577 */ 578 static inline int etr_mode_is_pps(struct etr_eacr eacr) 579 { 580 return eacr.es && !eacr.sl; 581 } 582 583 /* 584 * Check if the etr mode is etr. 585 */ 586 static inline int etr_mode_is_etr(struct etr_eacr eacr) 587 { 588 return eacr.es && eacr.sl; 589 } 590 591 /* 592 * Check if the port can be used for TOD synchronization. 593 * For PPS mode the port has to receive OTEs. For ETR mode 594 * the port has to receive OTEs, the ETR stepping bit has to 595 * be zero and the validity bits for data frame 1, 2, and 3 596 * have to be 1. 597 */ 598 static int etr_port_valid(struct etr_aib *aib, int port) 599 { 600 unsigned int psc; 601 602 /* Check that this port is receiving OTEs. */ 603 if (aib->tsp == 0) 604 return 0; 605 606 psc = port ? aib->esw.psc1 : aib->esw.psc0; 607 if (psc == etr_lpsc_pps_mode) 608 return 1; 609 if (psc == etr_lpsc_operational_step) 610 return !aib->esw.y && aib->slsw.v1 && 611 aib->slsw.v2 && aib->slsw.v3; 612 return 0; 613 } 614 615 /* 616 * Check if two ports are on the same network. 617 */ 618 static int etr_compare_network(struct etr_aib *aib1, struct etr_aib *aib2) 619 { 620 // FIXME: any other fields we have to compare? 621 return aib1->edf1.net_id == aib2->edf1.net_id; 622 } 623 624 /* 625 * Wrapper for etr_stei that converts physical port states 626 * to logical port states to be consistent with the output 627 * of stetr (see etr_psc vs. etr_lpsc). 628 */ 629 static void etr_steai_cv(struct etr_aib *aib, unsigned int func) 630 { 631 BUG_ON(etr_steai(aib, func) != 0); 632 /* Convert port state to logical port state. */ 633 if (aib->esw.psc0 == 1) 634 aib->esw.psc0 = 2; 635 else if (aib->esw.psc0 == 0 && aib->esw.p == 0) 636 aib->esw.psc0 = 1; 637 if (aib->esw.psc1 == 1) 638 aib->esw.psc1 = 2; 639 else if (aib->esw.psc1 == 0 && aib->esw.p == 1) 640 aib->esw.psc1 = 1; 641 } 642 643 /* 644 * Check if the aib a2 is still connected to the same attachment as 645 * aib a1, the etv values differ by one and a2 is valid. 646 */ 647 static int etr_aib_follows(struct etr_aib *a1, struct etr_aib *a2, int p) 648 { 649 int state_a1, state_a2; 650 651 /* Paranoia check: e0/e1 should better be the same. */ 652 if (a1->esw.eacr.e0 != a2->esw.eacr.e0 || 653 a1->esw.eacr.e1 != a2->esw.eacr.e1) 654 return 0; 655 656 /* Still connected to the same etr ? */ 657 state_a1 = p ? a1->esw.psc1 : a1->esw.psc0; 658 state_a2 = p ? a2->esw.psc1 : a2->esw.psc0; 659 if (state_a1 == etr_lpsc_operational_step) { 660 if (state_a2 != etr_lpsc_operational_step || 661 a1->edf1.net_id != a2->edf1.net_id || 662 a1->edf1.etr_id != a2->edf1.etr_id || 663 a1->edf1.etr_pn != a2->edf1.etr_pn) 664 return 0; 665 } else if (state_a2 != etr_lpsc_pps_mode) 666 return 0; 667 668 /* The ETV value of a2 needs to be ETV of a1 + 1. */ 669 if (a1->edf2.etv + 1 != a2->edf2.etv) 670 return 0; 671 672 if (!etr_port_valid(a2, p)) 673 return 0; 674 675 return 1; 676 } 677 678 struct clock_sync_data { 679 atomic_t cpus; 680 int in_sync; 681 unsigned long long fixup_cc; 682 int etr_port; 683 struct etr_aib *etr_aib; 684 }; 685 686 static void clock_sync_cpu(struct clock_sync_data *sync) 687 { 688 atomic_dec(&sync->cpus); 689 enable_sync_clock(); 690 /* 691 * This looks like a busy wait loop but it isn't. etr_sync_cpus 692 * is called on all other cpus while the TOD clocks is stopped. 693 * __udelay will stop the cpu on an enabled wait psw until the 694 * TOD is running again. 695 */ 696 while (sync->in_sync == 0) { 697 __udelay(1); 698 /* 699 * A different cpu changes *in_sync. Therefore use 700 * barrier() to force memory access. 701 */ 702 barrier(); 703 } 704 if (sync->in_sync != 1) 705 /* Didn't work. Clear per-cpu in sync bit again. */ 706 disable_sync_clock(NULL); 707 /* 708 * This round of TOD syncing is done. Set the clock comparator 709 * to the next tick and let the processor continue. 710 */ 711 fixup_clock_comparator(sync->fixup_cc); 712 } 713 714 /* 715 * Sync the TOD clock using the port refered to by aibp. This port 716 * has to be enabled and the other port has to be disabled. The 717 * last eacr update has to be more than 1.6 seconds in the past. 718 */ 719 static int etr_sync_clock(void *data) 720 { 721 static int first; 722 unsigned long long clock, old_clock, delay, delta; 723 struct clock_sync_data *etr_sync; 724 struct etr_aib *sync_port, *aib; 725 int port; 726 int rc; 727 728 etr_sync = data; 729 730 if (xchg(&first, 1) == 1) { 731 /* Slave */ 732 clock_sync_cpu(etr_sync); 733 return 0; 734 } 735 736 /* Wait until all other cpus entered the sync function. */ 737 while (atomic_read(&etr_sync->cpus) != 0) 738 cpu_relax(); 739 740 port = etr_sync->etr_port; 741 aib = etr_sync->etr_aib; 742 sync_port = (port == 0) ? &etr_port0 : &etr_port1; 743 enable_sync_clock(); 744 745 /* Set clock to next OTE. */ 746 __ctl_set_bit(14, 21); 747 __ctl_set_bit(0, 29); 748 clock = ((unsigned long long) (aib->edf2.etv + 1)) << 32; 749 old_clock = get_clock(); 750 if (set_clock(clock) == 0) { 751 __udelay(1); /* Wait for the clock to start. */ 752 __ctl_clear_bit(0, 29); 753 __ctl_clear_bit(14, 21); 754 etr_stetr(aib); 755 /* Adjust Linux timing variables. */ 756 delay = (unsigned long long) 757 (aib->edf2.etv - sync_port->edf2.etv) << 32; 758 delta = adjust_time(old_clock, clock, delay); 759 etr_sync->fixup_cc = delta; 760 fixup_clock_comparator(delta); 761 /* Verify that the clock is properly set. */ 762 if (!etr_aib_follows(sync_port, aib, port)) { 763 /* Didn't work. */ 764 disable_sync_clock(NULL); 765 etr_sync->in_sync = -EAGAIN; 766 rc = -EAGAIN; 767 } else { 768 etr_sync->in_sync = 1; 769 rc = 0; 770 } 771 } else { 772 /* Could not set the clock ?!? */ 773 __ctl_clear_bit(0, 29); 774 __ctl_clear_bit(14, 21); 775 disable_sync_clock(NULL); 776 etr_sync->in_sync = -EAGAIN; 777 rc = -EAGAIN; 778 } 779 xchg(&first, 0); 780 return rc; 781 } 782 783 static int etr_sync_clock_stop(struct etr_aib *aib, int port) 784 { 785 struct clock_sync_data etr_sync; 786 struct etr_aib *sync_port; 787 int follows; 788 int rc; 789 790 /* Check if the current aib is adjacent to the sync port aib. */ 791 sync_port = (port == 0) ? &etr_port0 : &etr_port1; 792 follows = etr_aib_follows(sync_port, aib, port); 793 memcpy(sync_port, aib, sizeof(*aib)); 794 if (!follows) 795 return -EAGAIN; 796 memset(&etr_sync, 0, sizeof(etr_sync)); 797 etr_sync.etr_aib = aib; 798 etr_sync.etr_port = port; 799 get_online_cpus(); 800 atomic_set(&etr_sync.cpus, num_online_cpus() - 1); 801 rc = stop_machine(etr_sync_clock, &etr_sync, &cpu_online_map); 802 put_online_cpus(); 803 return rc; 804 } 805 806 /* 807 * Handle the immediate effects of the different events. 808 * The port change event is used for online/offline changes. 809 */ 810 static struct etr_eacr etr_handle_events(struct etr_eacr eacr) 811 { 812 if (test_and_clear_bit(ETR_EVENT_SYNC_CHECK, &etr_events)) 813 eacr.es = 0; 814 if (test_and_clear_bit(ETR_EVENT_SWITCH_LOCAL, &etr_events)) 815 eacr.es = eacr.sl = 0; 816 if (test_and_clear_bit(ETR_EVENT_PORT_ALERT, &etr_events)) 817 etr_port0_uptodate = etr_port1_uptodate = 0; 818 819 if (test_and_clear_bit(ETR_EVENT_PORT0_CHANGE, &etr_events)) { 820 if (eacr.e0) 821 /* 822 * Port change of an enabled port. We have to 823 * assume that this can have caused an stepping 824 * port switch. 825 */ 826 etr_tolec = get_clock(); 827 eacr.p0 = etr_port0_online; 828 if (!eacr.p0) 829 eacr.e0 = 0; 830 etr_port0_uptodate = 0; 831 } 832 if (test_and_clear_bit(ETR_EVENT_PORT1_CHANGE, &etr_events)) { 833 if (eacr.e1) 834 /* 835 * Port change of an enabled port. We have to 836 * assume that this can have caused an stepping 837 * port switch. 838 */ 839 etr_tolec = get_clock(); 840 eacr.p1 = etr_port1_online; 841 if (!eacr.p1) 842 eacr.e1 = 0; 843 etr_port1_uptodate = 0; 844 } 845 clear_bit(ETR_EVENT_UPDATE, &etr_events); 846 return eacr; 847 } 848 849 /* 850 * Set up a timer that expires after the etr_tolec + 1.6 seconds if 851 * one of the ports needs an update. 852 */ 853 static void etr_set_tolec_timeout(unsigned long long now) 854 { 855 unsigned long micros; 856 857 if ((!etr_eacr.p0 || etr_port0_uptodate) && 858 (!etr_eacr.p1 || etr_port1_uptodate)) 859 return; 860 micros = (now > etr_tolec) ? ((now - etr_tolec) >> 12) : 0; 861 micros = (micros > 1600000) ? 0 : 1600000 - micros; 862 mod_timer(&etr_timer, jiffies + (micros * HZ) / 1000000 + 1); 863 } 864 865 /* 866 * Set up a time that expires after 1/2 second. 867 */ 868 static void etr_set_sync_timeout(void) 869 { 870 mod_timer(&etr_timer, jiffies + HZ/2); 871 } 872 873 /* 874 * Update the aib information for one or both ports. 875 */ 876 static struct etr_eacr etr_handle_update(struct etr_aib *aib, 877 struct etr_eacr eacr) 878 { 879 /* With both ports disabled the aib information is useless. */ 880 if (!eacr.e0 && !eacr.e1) 881 return eacr; 882 883 /* Update port0 or port1 with aib stored in etr_work_fn. */ 884 if (aib->esw.q == 0) { 885 /* Information for port 0 stored. */ 886 if (eacr.p0 && !etr_port0_uptodate) { 887 etr_port0 = *aib; 888 if (etr_port0_online) 889 etr_port0_uptodate = 1; 890 } 891 } else { 892 /* Information for port 1 stored. */ 893 if (eacr.p1 && !etr_port1_uptodate) { 894 etr_port1 = *aib; 895 if (etr_port0_online) 896 etr_port1_uptodate = 1; 897 } 898 } 899 900 /* 901 * Do not try to get the alternate port aib if the clock 902 * is not in sync yet. 903 */ 904 if (!check_sync_clock()) 905 return eacr; 906 907 /* 908 * If steai is available we can get the information about 909 * the other port immediately. If only stetr is available the 910 * data-port bit toggle has to be used. 911 */ 912 if (etr_steai_available) { 913 if (eacr.p0 && !etr_port0_uptodate) { 914 etr_steai_cv(&etr_port0, ETR_STEAI_PORT_0); 915 etr_port0_uptodate = 1; 916 } 917 if (eacr.p1 && !etr_port1_uptodate) { 918 etr_steai_cv(&etr_port1, ETR_STEAI_PORT_1); 919 etr_port1_uptodate = 1; 920 } 921 } else { 922 /* 923 * One port was updated above, if the other 924 * port is not uptodate toggle dp bit. 925 */ 926 if ((eacr.p0 && !etr_port0_uptodate) || 927 (eacr.p1 && !etr_port1_uptodate)) 928 eacr.dp ^= 1; 929 else 930 eacr.dp = 0; 931 } 932 return eacr; 933 } 934 935 /* 936 * Write new etr control register if it differs from the current one. 937 * Return 1 if etr_tolec has been updated as well. 938 */ 939 static void etr_update_eacr(struct etr_eacr eacr) 940 { 941 int dp_changed; 942 943 if (memcmp(&etr_eacr, &eacr, sizeof(eacr)) == 0) 944 /* No change, return. */ 945 return; 946 /* 947 * The disable of an active port of the change of the data port 948 * bit can/will cause a change in the data port. 949 */ 950 dp_changed = etr_eacr.e0 > eacr.e0 || etr_eacr.e1 > eacr.e1 || 951 (etr_eacr.dp ^ eacr.dp) != 0; 952 etr_eacr = eacr; 953 etr_setr(&etr_eacr); 954 if (dp_changed) 955 etr_tolec = get_clock(); 956 } 957 958 /* 959 * ETR work. In this function you'll find the main logic. In 960 * particular this is the only function that calls etr_update_eacr(), 961 * it "controls" the etr control register. 962 */ 963 static void etr_work_fn(struct work_struct *work) 964 { 965 unsigned long long now; 966 struct etr_eacr eacr; 967 struct etr_aib aib; 968 int sync_port; 969 970 /* prevent multiple execution. */ 971 mutex_lock(&etr_work_mutex); 972 973 /* Create working copy of etr_eacr. */ 974 eacr = etr_eacr; 975 976 /* Check for the different events and their immediate effects. */ 977 eacr = etr_handle_events(eacr); 978 979 /* Check if ETR is supposed to be active. */ 980 eacr.ea = eacr.p0 || eacr.p1; 981 if (!eacr.ea) { 982 /* Both ports offline. Reset everything. */ 983 eacr.dp = eacr.es = eacr.sl = 0; 984 on_each_cpu(disable_sync_clock, NULL, 1); 985 del_timer_sync(&etr_timer); 986 etr_update_eacr(eacr); 987 goto out_unlock; 988 } 989 990 /* Store aib to get the current ETR status word. */ 991 BUG_ON(etr_stetr(&aib) != 0); 992 etr_port0.esw = etr_port1.esw = aib.esw; /* Copy status word. */ 993 now = get_clock(); 994 995 /* 996 * Update the port information if the last stepping port change 997 * or data port change is older than 1.6 seconds. 998 */ 999 if (now >= etr_tolec + (1600000 << 12)) 1000 eacr = etr_handle_update(&aib, eacr); 1001 1002 /* 1003 * Select ports to enable. The prefered synchronization mode is PPS. 1004 * If a port can be enabled depends on a number of things: 1005 * 1) The port needs to be online and uptodate. A port is not 1006 * disabled just because it is not uptodate, but it is only 1007 * enabled if it is uptodate. 1008 * 2) The port needs to have the same mode (pps / etr). 1009 * 3) The port needs to be usable -> etr_port_valid() == 1 1010 * 4) To enable the second port the clock needs to be in sync. 1011 * 5) If both ports are useable and are ETR ports, the network id 1012 * has to be the same. 1013 * The eacr.sl bit is used to indicate etr mode vs. pps mode. 1014 */ 1015 if (eacr.p0 && aib.esw.psc0 == etr_lpsc_pps_mode) { 1016 eacr.sl = 0; 1017 eacr.e0 = 1; 1018 if (!etr_mode_is_pps(etr_eacr)) 1019 eacr.es = 0; 1020 if (!eacr.es || !eacr.p1 || aib.esw.psc1 != etr_lpsc_pps_mode) 1021 eacr.e1 = 0; 1022 // FIXME: uptodate checks ? 1023 else if (etr_port0_uptodate && etr_port1_uptodate) 1024 eacr.e1 = 1; 1025 sync_port = (etr_port0_uptodate && 1026 etr_port_valid(&etr_port0, 0)) ? 0 : -1; 1027 } else if (eacr.p1 && aib.esw.psc1 == etr_lpsc_pps_mode) { 1028 eacr.sl = 0; 1029 eacr.e0 = 0; 1030 eacr.e1 = 1; 1031 if (!etr_mode_is_pps(etr_eacr)) 1032 eacr.es = 0; 1033 sync_port = (etr_port1_uptodate && 1034 etr_port_valid(&etr_port1, 1)) ? 1 : -1; 1035 } else if (eacr.p0 && aib.esw.psc0 == etr_lpsc_operational_step) { 1036 eacr.sl = 1; 1037 eacr.e0 = 1; 1038 if (!etr_mode_is_etr(etr_eacr)) 1039 eacr.es = 0; 1040 if (!eacr.es || !eacr.p1 || 1041 aib.esw.psc1 != etr_lpsc_operational_alt) 1042 eacr.e1 = 0; 1043 else if (etr_port0_uptodate && etr_port1_uptodate && 1044 etr_compare_network(&etr_port0, &etr_port1)) 1045 eacr.e1 = 1; 1046 sync_port = (etr_port0_uptodate && 1047 etr_port_valid(&etr_port0, 0)) ? 0 : -1; 1048 } else if (eacr.p1 && aib.esw.psc1 == etr_lpsc_operational_step) { 1049 eacr.sl = 1; 1050 eacr.e0 = 0; 1051 eacr.e1 = 1; 1052 if (!etr_mode_is_etr(etr_eacr)) 1053 eacr.es = 0; 1054 sync_port = (etr_port1_uptodate && 1055 etr_port_valid(&etr_port1, 1)) ? 1 : -1; 1056 } else { 1057 /* Both ports not usable. */ 1058 eacr.es = eacr.sl = 0; 1059 sync_port = -1; 1060 } 1061 1062 /* 1063 * If the clock is in sync just update the eacr and return. 1064 * If there is no valid sync port wait for a port update. 1065 */ 1066 if (check_sync_clock() || sync_port < 0) { 1067 etr_update_eacr(eacr); 1068 etr_set_tolec_timeout(now); 1069 goto out_unlock; 1070 } 1071 1072 /* 1073 * Prepare control register for clock syncing 1074 * (reset data port bit, set sync check control. 1075 */ 1076 eacr.dp = 0; 1077 eacr.es = 1; 1078 1079 /* 1080 * Update eacr and try to synchronize the clock. If the update 1081 * of eacr caused a stepping port switch (or if we have to 1082 * assume that a stepping port switch has occured) or the 1083 * clock syncing failed, reset the sync check control bit 1084 * and set up a timer to try again after 0.5 seconds 1085 */ 1086 etr_update_eacr(eacr); 1087 if (now < etr_tolec + (1600000 << 12) || 1088 etr_sync_clock_stop(&aib, sync_port) != 0) { 1089 /* Sync failed. Try again in 1/2 second. */ 1090 eacr.es = 0; 1091 etr_update_eacr(eacr); 1092 etr_set_sync_timeout(); 1093 } else 1094 etr_set_tolec_timeout(now); 1095 out_unlock: 1096 mutex_unlock(&etr_work_mutex); 1097 } 1098 1099 /* 1100 * Sysfs interface functions 1101 */ 1102 static struct sysdev_class etr_sysclass = { 1103 .name = "etr", 1104 }; 1105 1106 static struct sys_device etr_port0_dev = { 1107 .id = 0, 1108 .cls = &etr_sysclass, 1109 }; 1110 1111 static struct sys_device etr_port1_dev = { 1112 .id = 1, 1113 .cls = &etr_sysclass, 1114 }; 1115 1116 /* 1117 * ETR class attributes 1118 */ 1119 static ssize_t etr_stepping_port_show(struct sysdev_class *class, 1120 struct sysdev_class_attribute *attr, 1121 char *buf) 1122 { 1123 return sprintf(buf, "%i\n", etr_port0.esw.p); 1124 } 1125 1126 static SYSDEV_CLASS_ATTR(stepping_port, 0400, etr_stepping_port_show, NULL); 1127 1128 static ssize_t etr_stepping_mode_show(struct sysdev_class *class, 1129 struct sysdev_class_attribute *attr, 1130 char *buf) 1131 { 1132 char *mode_str; 1133 1134 if (etr_mode_is_pps(etr_eacr)) 1135 mode_str = "pps"; 1136 else if (etr_mode_is_etr(etr_eacr)) 1137 mode_str = "etr"; 1138 else 1139 mode_str = "local"; 1140 return sprintf(buf, "%s\n", mode_str); 1141 } 1142 1143 static SYSDEV_CLASS_ATTR(stepping_mode, 0400, etr_stepping_mode_show, NULL); 1144 1145 /* 1146 * ETR port attributes 1147 */ 1148 static inline struct etr_aib *etr_aib_from_dev(struct sys_device *dev) 1149 { 1150 if (dev == &etr_port0_dev) 1151 return etr_port0_online ? &etr_port0 : NULL; 1152 else 1153 return etr_port1_online ? &etr_port1 : NULL; 1154 } 1155 1156 static ssize_t etr_online_show(struct sys_device *dev, 1157 struct sysdev_attribute *attr, 1158 char *buf) 1159 { 1160 unsigned int online; 1161 1162 online = (dev == &etr_port0_dev) ? etr_port0_online : etr_port1_online; 1163 return sprintf(buf, "%i\n", online); 1164 } 1165 1166 static ssize_t etr_online_store(struct sys_device *dev, 1167 struct sysdev_attribute *attr, 1168 const char *buf, size_t count) 1169 { 1170 unsigned int value; 1171 1172 value = simple_strtoul(buf, NULL, 0); 1173 if (value != 0 && value != 1) 1174 return -EINVAL; 1175 if (!test_bit(CLOCK_SYNC_HAS_ETR, &clock_sync_flags)) 1176 return -EOPNOTSUPP; 1177 mutex_lock(&clock_sync_mutex); 1178 if (dev == &etr_port0_dev) { 1179 if (etr_port0_online == value) 1180 goto out; /* Nothing to do. */ 1181 etr_port0_online = value; 1182 if (etr_port0_online && etr_port1_online) 1183 set_bit(CLOCK_SYNC_ETR, &clock_sync_flags); 1184 else 1185 clear_bit(CLOCK_SYNC_ETR, &clock_sync_flags); 1186 set_bit(ETR_EVENT_PORT0_CHANGE, &etr_events); 1187 queue_work(time_sync_wq, &etr_work); 1188 } else { 1189 if (etr_port1_online == value) 1190 goto out; /* Nothing to do. */ 1191 etr_port1_online = value; 1192 if (etr_port0_online && etr_port1_online) 1193 set_bit(CLOCK_SYNC_ETR, &clock_sync_flags); 1194 else 1195 clear_bit(CLOCK_SYNC_ETR, &clock_sync_flags); 1196 set_bit(ETR_EVENT_PORT1_CHANGE, &etr_events); 1197 queue_work(time_sync_wq, &etr_work); 1198 } 1199 out: 1200 mutex_unlock(&clock_sync_mutex); 1201 return count; 1202 } 1203 1204 static SYSDEV_ATTR(online, 0600, etr_online_show, etr_online_store); 1205 1206 static ssize_t etr_stepping_control_show(struct sys_device *dev, 1207 struct sysdev_attribute *attr, 1208 char *buf) 1209 { 1210 return sprintf(buf, "%i\n", (dev == &etr_port0_dev) ? 1211 etr_eacr.e0 : etr_eacr.e1); 1212 } 1213 1214 static SYSDEV_ATTR(stepping_control, 0400, etr_stepping_control_show, NULL); 1215 1216 static ssize_t etr_mode_code_show(struct sys_device *dev, 1217 struct sysdev_attribute *attr, char *buf) 1218 { 1219 if (!etr_port0_online && !etr_port1_online) 1220 /* Status word is not uptodate if both ports are offline. */ 1221 return -ENODATA; 1222 return sprintf(buf, "%i\n", (dev == &etr_port0_dev) ? 1223 etr_port0.esw.psc0 : etr_port0.esw.psc1); 1224 } 1225 1226 static SYSDEV_ATTR(state_code, 0400, etr_mode_code_show, NULL); 1227 1228 static ssize_t etr_untuned_show(struct sys_device *dev, 1229 struct sysdev_attribute *attr, char *buf) 1230 { 1231 struct etr_aib *aib = etr_aib_from_dev(dev); 1232 1233 if (!aib || !aib->slsw.v1) 1234 return -ENODATA; 1235 return sprintf(buf, "%i\n", aib->edf1.u); 1236 } 1237 1238 static SYSDEV_ATTR(untuned, 0400, etr_untuned_show, NULL); 1239 1240 static ssize_t etr_network_id_show(struct sys_device *dev, 1241 struct sysdev_attribute *attr, char *buf) 1242 { 1243 struct etr_aib *aib = etr_aib_from_dev(dev); 1244 1245 if (!aib || !aib->slsw.v1) 1246 return -ENODATA; 1247 return sprintf(buf, "%i\n", aib->edf1.net_id); 1248 } 1249 1250 static SYSDEV_ATTR(network, 0400, etr_network_id_show, NULL); 1251 1252 static ssize_t etr_id_show(struct sys_device *dev, 1253 struct sysdev_attribute *attr, char *buf) 1254 { 1255 struct etr_aib *aib = etr_aib_from_dev(dev); 1256 1257 if (!aib || !aib->slsw.v1) 1258 return -ENODATA; 1259 return sprintf(buf, "%i\n", aib->edf1.etr_id); 1260 } 1261 1262 static SYSDEV_ATTR(id, 0400, etr_id_show, NULL); 1263 1264 static ssize_t etr_port_number_show(struct sys_device *dev, 1265 struct sysdev_attribute *attr, char *buf) 1266 { 1267 struct etr_aib *aib = etr_aib_from_dev(dev); 1268 1269 if (!aib || !aib->slsw.v1) 1270 return -ENODATA; 1271 return sprintf(buf, "%i\n", aib->edf1.etr_pn); 1272 } 1273 1274 static SYSDEV_ATTR(port, 0400, etr_port_number_show, NULL); 1275 1276 static ssize_t etr_coupled_show(struct sys_device *dev, 1277 struct sysdev_attribute *attr, char *buf) 1278 { 1279 struct etr_aib *aib = etr_aib_from_dev(dev); 1280 1281 if (!aib || !aib->slsw.v3) 1282 return -ENODATA; 1283 return sprintf(buf, "%i\n", aib->edf3.c); 1284 } 1285 1286 static SYSDEV_ATTR(coupled, 0400, etr_coupled_show, NULL); 1287 1288 static ssize_t etr_local_time_show(struct sys_device *dev, 1289 struct sysdev_attribute *attr, char *buf) 1290 { 1291 struct etr_aib *aib = etr_aib_from_dev(dev); 1292 1293 if (!aib || !aib->slsw.v3) 1294 return -ENODATA; 1295 return sprintf(buf, "%i\n", aib->edf3.blto); 1296 } 1297 1298 static SYSDEV_ATTR(local_time, 0400, etr_local_time_show, NULL); 1299 1300 static ssize_t etr_utc_offset_show(struct sys_device *dev, 1301 struct sysdev_attribute *attr, char *buf) 1302 { 1303 struct etr_aib *aib = etr_aib_from_dev(dev); 1304 1305 if (!aib || !aib->slsw.v3) 1306 return -ENODATA; 1307 return sprintf(buf, "%i\n", aib->edf3.buo); 1308 } 1309 1310 static SYSDEV_ATTR(utc_offset, 0400, etr_utc_offset_show, NULL); 1311 1312 static struct sysdev_attribute *etr_port_attributes[] = { 1313 &attr_online, 1314 &attr_stepping_control, 1315 &attr_state_code, 1316 &attr_untuned, 1317 &attr_network, 1318 &attr_id, 1319 &attr_port, 1320 &attr_coupled, 1321 &attr_local_time, 1322 &attr_utc_offset, 1323 NULL 1324 }; 1325 1326 static int __init etr_register_port(struct sys_device *dev) 1327 { 1328 struct sysdev_attribute **attr; 1329 int rc; 1330 1331 rc = sysdev_register(dev); 1332 if (rc) 1333 goto out; 1334 for (attr = etr_port_attributes; *attr; attr++) { 1335 rc = sysdev_create_file(dev, *attr); 1336 if (rc) 1337 goto out_unreg; 1338 } 1339 return 0; 1340 out_unreg: 1341 for (; attr >= etr_port_attributes; attr--) 1342 sysdev_remove_file(dev, *attr); 1343 sysdev_unregister(dev); 1344 out: 1345 return rc; 1346 } 1347 1348 static void __init etr_unregister_port(struct sys_device *dev) 1349 { 1350 struct sysdev_attribute **attr; 1351 1352 for (attr = etr_port_attributes; *attr; attr++) 1353 sysdev_remove_file(dev, *attr); 1354 sysdev_unregister(dev); 1355 } 1356 1357 static int __init etr_init_sysfs(void) 1358 { 1359 int rc; 1360 1361 rc = sysdev_class_register(&etr_sysclass); 1362 if (rc) 1363 goto out; 1364 rc = sysdev_class_create_file(&etr_sysclass, &attr_stepping_port); 1365 if (rc) 1366 goto out_unreg_class; 1367 rc = sysdev_class_create_file(&etr_sysclass, &attr_stepping_mode); 1368 if (rc) 1369 goto out_remove_stepping_port; 1370 rc = etr_register_port(&etr_port0_dev); 1371 if (rc) 1372 goto out_remove_stepping_mode; 1373 rc = etr_register_port(&etr_port1_dev); 1374 if (rc) 1375 goto out_remove_port0; 1376 return 0; 1377 1378 out_remove_port0: 1379 etr_unregister_port(&etr_port0_dev); 1380 out_remove_stepping_mode: 1381 sysdev_class_remove_file(&etr_sysclass, &attr_stepping_mode); 1382 out_remove_stepping_port: 1383 sysdev_class_remove_file(&etr_sysclass, &attr_stepping_port); 1384 out_unreg_class: 1385 sysdev_class_unregister(&etr_sysclass); 1386 out: 1387 return rc; 1388 } 1389 1390 device_initcall(etr_init_sysfs); 1391 1392 /* 1393 * Server Time Protocol (STP) code. 1394 */ 1395 static int stp_online; 1396 static struct stp_sstpi stp_info; 1397 static void *stp_page; 1398 1399 static void stp_work_fn(struct work_struct *work); 1400 static DEFINE_MUTEX(stp_work_mutex); 1401 static DECLARE_WORK(stp_work, stp_work_fn); 1402 static struct timer_list stp_timer; 1403 1404 static int __init early_parse_stp(char *p) 1405 { 1406 if (strncmp(p, "off", 3) == 0) 1407 stp_online = 0; 1408 else if (strncmp(p, "on", 2) == 0) 1409 stp_online = 1; 1410 return 0; 1411 } 1412 early_param("stp", early_parse_stp); 1413 1414 /* 1415 * Reset STP attachment. 1416 */ 1417 static void __init stp_reset(void) 1418 { 1419 int rc; 1420 1421 stp_page = (void *) get_zeroed_page(GFP_ATOMIC); 1422 rc = chsc_sstpc(stp_page, STP_OP_CTRL, 0x0000); 1423 if (rc == 0) 1424 set_bit(CLOCK_SYNC_HAS_STP, &clock_sync_flags); 1425 else if (stp_online) { 1426 pr_warning("The real or virtual hardware system does " 1427 "not provide an STP interface\n"); 1428 free_page((unsigned long) stp_page); 1429 stp_page = NULL; 1430 stp_online = 0; 1431 } 1432 } 1433 1434 static void stp_timeout(unsigned long dummy) 1435 { 1436 queue_work(time_sync_wq, &stp_work); 1437 } 1438 1439 static int __init stp_init(void) 1440 { 1441 if (!test_bit(CLOCK_SYNC_HAS_STP, &clock_sync_flags)) 1442 return 0; 1443 setup_timer(&stp_timer, stp_timeout, 0UL); 1444 time_init_wq(); 1445 if (!stp_online) 1446 return 0; 1447 queue_work(time_sync_wq, &stp_work); 1448 return 0; 1449 } 1450 1451 arch_initcall(stp_init); 1452 1453 /* 1454 * STP timing alert. There are three causes: 1455 * 1) timing status change 1456 * 2) link availability change 1457 * 3) time control parameter change 1458 * In all three cases we are only interested in the clock source state. 1459 * If a STP clock source is now available use it. 1460 */ 1461 static void stp_timing_alert(struct stp_irq_parm *intparm) 1462 { 1463 if (intparm->tsc || intparm->lac || intparm->tcpc) 1464 queue_work(time_sync_wq, &stp_work); 1465 } 1466 1467 /* 1468 * STP sync check machine check. This is called when the timing state 1469 * changes from the synchronized state to the unsynchronized state. 1470 * After a STP sync check the clock is not in sync. The machine check 1471 * is broadcasted to all cpus at the same time. 1472 */ 1473 void stp_sync_check(void) 1474 { 1475 disable_sync_clock(NULL); 1476 queue_work(time_sync_wq, &stp_work); 1477 } 1478 1479 /* 1480 * STP island condition machine check. This is called when an attached 1481 * server attempts to communicate over an STP link and the servers 1482 * have matching CTN ids and have a valid stratum-1 configuration 1483 * but the configurations do not match. 1484 */ 1485 void stp_island_check(void) 1486 { 1487 disable_sync_clock(NULL); 1488 queue_work(time_sync_wq, &stp_work); 1489 } 1490 1491 1492 static int stp_sync_clock(void *data) 1493 { 1494 static int first; 1495 unsigned long long old_clock, delta; 1496 struct clock_sync_data *stp_sync; 1497 int rc; 1498 1499 stp_sync = data; 1500 1501 if (xchg(&first, 1) == 1) { 1502 /* Slave */ 1503 clock_sync_cpu(stp_sync); 1504 return 0; 1505 } 1506 1507 /* Wait until all other cpus entered the sync function. */ 1508 while (atomic_read(&stp_sync->cpus) != 0) 1509 cpu_relax(); 1510 1511 enable_sync_clock(); 1512 1513 rc = 0; 1514 if (stp_info.todoff[0] || stp_info.todoff[1] || 1515 stp_info.todoff[2] || stp_info.todoff[3] || 1516 stp_info.tmd != 2) { 1517 old_clock = get_clock(); 1518 rc = chsc_sstpc(stp_page, STP_OP_SYNC, 0); 1519 if (rc == 0) { 1520 delta = adjust_time(old_clock, get_clock(), 0); 1521 fixup_clock_comparator(delta); 1522 rc = chsc_sstpi(stp_page, &stp_info, 1523 sizeof(struct stp_sstpi)); 1524 if (rc == 0 && stp_info.tmd != 2) 1525 rc = -EAGAIN; 1526 } 1527 } 1528 if (rc) { 1529 disable_sync_clock(NULL); 1530 stp_sync->in_sync = -EAGAIN; 1531 } else 1532 stp_sync->in_sync = 1; 1533 xchg(&first, 0); 1534 return 0; 1535 } 1536 1537 /* 1538 * STP work. Check for the STP state and take over the clock 1539 * synchronization if the STP clock source is usable. 1540 */ 1541 static void stp_work_fn(struct work_struct *work) 1542 { 1543 struct clock_sync_data stp_sync; 1544 int rc; 1545 1546 /* prevent multiple execution. */ 1547 mutex_lock(&stp_work_mutex); 1548 1549 if (!stp_online) { 1550 chsc_sstpc(stp_page, STP_OP_CTRL, 0x0000); 1551 del_timer_sync(&stp_timer); 1552 goto out_unlock; 1553 } 1554 1555 rc = chsc_sstpc(stp_page, STP_OP_CTRL, 0xb0e0); 1556 if (rc) 1557 goto out_unlock; 1558 1559 rc = chsc_sstpi(stp_page, &stp_info, sizeof(struct stp_sstpi)); 1560 if (rc || stp_info.c == 0) 1561 goto out_unlock; 1562 1563 /* Skip synchronization if the clock is already in sync. */ 1564 if (check_sync_clock()) 1565 goto out_unlock; 1566 1567 memset(&stp_sync, 0, sizeof(stp_sync)); 1568 get_online_cpus(); 1569 atomic_set(&stp_sync.cpus, num_online_cpus() - 1); 1570 stop_machine(stp_sync_clock, &stp_sync, &cpu_online_map); 1571 put_online_cpus(); 1572 1573 if (!check_sync_clock()) 1574 /* 1575 * There is a usable clock but the synchonization failed. 1576 * Retry after a second. 1577 */ 1578 mod_timer(&stp_timer, jiffies + HZ); 1579 1580 out_unlock: 1581 mutex_unlock(&stp_work_mutex); 1582 } 1583 1584 /* 1585 * STP class sysfs interface functions 1586 */ 1587 static struct sysdev_class stp_sysclass = { 1588 .name = "stp", 1589 }; 1590 1591 static ssize_t stp_ctn_id_show(struct sysdev_class *class, 1592 struct sysdev_class_attribute *attr, 1593 char *buf) 1594 { 1595 if (!stp_online) 1596 return -ENODATA; 1597 return sprintf(buf, "%016llx\n", 1598 *(unsigned long long *) stp_info.ctnid); 1599 } 1600 1601 static SYSDEV_CLASS_ATTR(ctn_id, 0400, stp_ctn_id_show, NULL); 1602 1603 static ssize_t stp_ctn_type_show(struct sysdev_class *class, 1604 struct sysdev_class_attribute *attr, 1605 char *buf) 1606 { 1607 if (!stp_online) 1608 return -ENODATA; 1609 return sprintf(buf, "%i\n", stp_info.ctn); 1610 } 1611 1612 static SYSDEV_CLASS_ATTR(ctn_type, 0400, stp_ctn_type_show, NULL); 1613 1614 static ssize_t stp_dst_offset_show(struct sysdev_class *class, 1615 struct sysdev_class_attribute *attr, 1616 char *buf) 1617 { 1618 if (!stp_online || !(stp_info.vbits & 0x2000)) 1619 return -ENODATA; 1620 return sprintf(buf, "%i\n", (int)(s16) stp_info.dsto); 1621 } 1622 1623 static SYSDEV_CLASS_ATTR(dst_offset, 0400, stp_dst_offset_show, NULL); 1624 1625 static ssize_t stp_leap_seconds_show(struct sysdev_class *class, 1626 struct sysdev_class_attribute *attr, 1627 char *buf) 1628 { 1629 if (!stp_online || !(stp_info.vbits & 0x8000)) 1630 return -ENODATA; 1631 return sprintf(buf, "%i\n", (int)(s16) stp_info.leaps); 1632 } 1633 1634 static SYSDEV_CLASS_ATTR(leap_seconds, 0400, stp_leap_seconds_show, NULL); 1635 1636 static ssize_t stp_stratum_show(struct sysdev_class *class, 1637 struct sysdev_class_attribute *attr, 1638 char *buf) 1639 { 1640 if (!stp_online) 1641 return -ENODATA; 1642 return sprintf(buf, "%i\n", (int)(s16) stp_info.stratum); 1643 } 1644 1645 static SYSDEV_CLASS_ATTR(stratum, 0400, stp_stratum_show, NULL); 1646 1647 static ssize_t stp_time_offset_show(struct sysdev_class *class, 1648 struct sysdev_class_attribute *attr, 1649 char *buf) 1650 { 1651 if (!stp_online || !(stp_info.vbits & 0x0800)) 1652 return -ENODATA; 1653 return sprintf(buf, "%i\n", (int) stp_info.tto); 1654 } 1655 1656 static SYSDEV_CLASS_ATTR(time_offset, 0400, stp_time_offset_show, NULL); 1657 1658 static ssize_t stp_time_zone_offset_show(struct sysdev_class *class, 1659 struct sysdev_class_attribute *attr, 1660 char *buf) 1661 { 1662 if (!stp_online || !(stp_info.vbits & 0x4000)) 1663 return -ENODATA; 1664 return sprintf(buf, "%i\n", (int)(s16) stp_info.tzo); 1665 } 1666 1667 static SYSDEV_CLASS_ATTR(time_zone_offset, 0400, 1668 stp_time_zone_offset_show, NULL); 1669 1670 static ssize_t stp_timing_mode_show(struct sysdev_class *class, 1671 struct sysdev_class_attribute *attr, 1672 char *buf) 1673 { 1674 if (!stp_online) 1675 return -ENODATA; 1676 return sprintf(buf, "%i\n", stp_info.tmd); 1677 } 1678 1679 static SYSDEV_CLASS_ATTR(timing_mode, 0400, stp_timing_mode_show, NULL); 1680 1681 static ssize_t stp_timing_state_show(struct sysdev_class *class, 1682 struct sysdev_class_attribute *attr, 1683 char *buf) 1684 { 1685 if (!stp_online) 1686 return -ENODATA; 1687 return sprintf(buf, "%i\n", stp_info.tst); 1688 } 1689 1690 static SYSDEV_CLASS_ATTR(timing_state, 0400, stp_timing_state_show, NULL); 1691 1692 static ssize_t stp_online_show(struct sysdev_class *class, 1693 struct sysdev_class_attribute *attr, 1694 char *buf) 1695 { 1696 return sprintf(buf, "%i\n", stp_online); 1697 } 1698 1699 static ssize_t stp_online_store(struct sysdev_class *class, 1700 struct sysdev_class_attribute *attr, 1701 const char *buf, size_t count) 1702 { 1703 unsigned int value; 1704 1705 value = simple_strtoul(buf, NULL, 0); 1706 if (value != 0 && value != 1) 1707 return -EINVAL; 1708 if (!test_bit(CLOCK_SYNC_HAS_STP, &clock_sync_flags)) 1709 return -EOPNOTSUPP; 1710 mutex_lock(&clock_sync_mutex); 1711 stp_online = value; 1712 if (stp_online) 1713 set_bit(CLOCK_SYNC_STP, &clock_sync_flags); 1714 else 1715 clear_bit(CLOCK_SYNC_STP, &clock_sync_flags); 1716 queue_work(time_sync_wq, &stp_work); 1717 mutex_unlock(&clock_sync_mutex); 1718 return count; 1719 } 1720 1721 /* 1722 * Can't use SYSDEV_CLASS_ATTR because the attribute should be named 1723 * stp/online but attr_online already exists in this file .. 1724 */ 1725 static struct sysdev_class_attribute attr_stp_online = { 1726 .attr = { .name = "online", .mode = 0600 }, 1727 .show = stp_online_show, 1728 .store = stp_online_store, 1729 }; 1730 1731 static struct sysdev_class_attribute *stp_attributes[] = { 1732 &attr_ctn_id, 1733 &attr_ctn_type, 1734 &attr_dst_offset, 1735 &attr_leap_seconds, 1736 &attr_stp_online, 1737 &attr_stratum, 1738 &attr_time_offset, 1739 &attr_time_zone_offset, 1740 &attr_timing_mode, 1741 &attr_timing_state, 1742 NULL 1743 }; 1744 1745 static int __init stp_init_sysfs(void) 1746 { 1747 struct sysdev_class_attribute **attr; 1748 int rc; 1749 1750 rc = sysdev_class_register(&stp_sysclass); 1751 if (rc) 1752 goto out; 1753 for (attr = stp_attributes; *attr; attr++) { 1754 rc = sysdev_class_create_file(&stp_sysclass, *attr); 1755 if (rc) 1756 goto out_unreg; 1757 } 1758 return 0; 1759 out_unreg: 1760 for (; attr >= stp_attributes; attr--) 1761 sysdev_class_remove_file(&stp_sysclass, *attr); 1762 sysdev_class_unregister(&stp_sysclass); 1763 out: 1764 return rc; 1765 } 1766 1767 device_initcall(stp_init_sysfs); 1768