1 /* 2 * Time of day based timer functions. 3 * 4 * S390 version 5 * Copyright IBM Corp. 1999, 2008 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 14 #define KMSG_COMPONENT "time" 15 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt 16 17 #include <linux/kernel_stat.h> 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/device.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/timekeeper_internal.h> 38 #include <linux/clockchips.h> 39 #include <linux/gfp.h> 40 #include <linux/kprobes.h> 41 #include <asm/uaccess.h> 42 #include <asm/delay.h> 43 #include <asm/div64.h> 44 #include <asm/vdso.h> 45 #include <asm/irq.h> 46 #include <asm/irq_regs.h> 47 #include <asm/vtimer.h> 48 #include <asm/etr.h> 49 #include <asm/cio.h> 50 #include "entry.h" 51 52 /* change this if you have some constant time drift */ 53 #define USECS_PER_JIFFY ((unsigned long) 1000000/HZ) 54 #define CLK_TICKS_PER_JIFFY ((unsigned long) USECS_PER_JIFFY << 12) 55 56 u64 sched_clock_base_cc = -1; /* Force to data section. */ 57 EXPORT_SYMBOL_GPL(sched_clock_base_cc); 58 59 static DEFINE_PER_CPU(struct clock_event_device, comparators); 60 61 /* 62 * Scheduler clock - returns current time in nanosec units. 63 */ 64 unsigned long long notrace __kprobes sched_clock(void) 65 { 66 return tod_to_ns(get_tod_clock_monotonic()); 67 } 68 69 /* 70 * Monotonic_clock - returns # of nanoseconds passed since time_init() 71 */ 72 unsigned long long monotonic_clock(void) 73 { 74 return sched_clock(); 75 } 76 EXPORT_SYMBOL(monotonic_clock); 77 78 void tod_to_timeval(__u64 todval, struct timespec *xt) 79 { 80 unsigned long long sec; 81 82 sec = todval >> 12; 83 do_div(sec, 1000000); 84 xt->tv_sec = sec; 85 todval -= (sec * 1000000) << 12; 86 xt->tv_nsec = ((todval * 1000) >> 12); 87 } 88 EXPORT_SYMBOL(tod_to_timeval); 89 90 void clock_comparator_work(void) 91 { 92 struct clock_event_device *cd; 93 94 S390_lowcore.clock_comparator = -1ULL; 95 set_clock_comparator(S390_lowcore.clock_comparator); 96 cd = &__get_cpu_var(comparators); 97 cd->event_handler(cd); 98 } 99 100 /* 101 * Fixup the clock comparator. 102 */ 103 static void fixup_clock_comparator(unsigned long long delta) 104 { 105 /* If nobody is waiting there's nothing to fix. */ 106 if (S390_lowcore.clock_comparator == -1ULL) 107 return; 108 S390_lowcore.clock_comparator += delta; 109 set_clock_comparator(S390_lowcore.clock_comparator); 110 } 111 112 static int s390_next_ktime(ktime_t expires, 113 struct clock_event_device *evt) 114 { 115 struct timespec ts; 116 u64 nsecs; 117 118 ts.tv_sec = ts.tv_nsec = 0; 119 monotonic_to_bootbased(&ts); 120 nsecs = ktime_to_ns(ktime_add(timespec_to_ktime(ts), expires)); 121 do_div(nsecs, 125); 122 S390_lowcore.clock_comparator = sched_clock_base_cc + (nsecs << 9); 123 /* Program the maximum value if we have an overflow (== year 2042) */ 124 if (unlikely(S390_lowcore.clock_comparator < sched_clock_base_cc)) 125 S390_lowcore.clock_comparator = -1ULL; 126 set_clock_comparator(S390_lowcore.clock_comparator); 127 return 0; 128 } 129 130 static void s390_set_mode(enum clock_event_mode mode, 131 struct clock_event_device *evt) 132 { 133 } 134 135 /* 136 * Set up lowcore and control register of the current cpu to 137 * enable TOD clock and clock comparator interrupts. 138 */ 139 void init_cpu_timer(void) 140 { 141 struct clock_event_device *cd; 142 int cpu; 143 144 S390_lowcore.clock_comparator = -1ULL; 145 set_clock_comparator(S390_lowcore.clock_comparator); 146 147 cpu = smp_processor_id(); 148 cd = &per_cpu(comparators, cpu); 149 cd->name = "comparator"; 150 cd->features = CLOCK_EVT_FEAT_ONESHOT | 151 CLOCK_EVT_FEAT_KTIME; 152 cd->mult = 16777; 153 cd->shift = 12; 154 cd->min_delta_ns = 1; 155 cd->max_delta_ns = LONG_MAX; 156 cd->rating = 400; 157 cd->cpumask = cpumask_of(cpu); 158 cd->set_next_ktime = s390_next_ktime; 159 cd->set_mode = s390_set_mode; 160 161 clockevents_register_device(cd); 162 163 /* Enable clock comparator timer interrupt. */ 164 __ctl_set_bit(0,11); 165 166 /* Always allow the timing alert external interrupt. */ 167 __ctl_set_bit(0, 4); 168 } 169 170 static void clock_comparator_interrupt(struct ext_code ext_code, 171 unsigned int param32, 172 unsigned long param64) 173 { 174 inc_irq_stat(IRQEXT_CLK); 175 if (S390_lowcore.clock_comparator == -1ULL) 176 set_clock_comparator(S390_lowcore.clock_comparator); 177 } 178 179 static void etr_timing_alert(struct etr_irq_parm *); 180 static void stp_timing_alert(struct stp_irq_parm *); 181 182 static void timing_alert_interrupt(struct ext_code ext_code, 183 unsigned int param32, unsigned long param64) 184 { 185 inc_irq_stat(IRQEXT_TLA); 186 if (param32 & 0x00c40000) 187 etr_timing_alert((struct etr_irq_parm *) ¶m32); 188 if (param32 & 0x00038000) 189 stp_timing_alert((struct stp_irq_parm *) ¶m32); 190 } 191 192 static void etr_reset(void); 193 static void stp_reset(void); 194 195 void read_persistent_clock(struct timespec *ts) 196 { 197 tod_to_timeval(get_tod_clock() - TOD_UNIX_EPOCH, ts); 198 } 199 200 void read_boot_clock(struct timespec *ts) 201 { 202 tod_to_timeval(sched_clock_base_cc - TOD_UNIX_EPOCH, ts); 203 } 204 205 static cycle_t read_tod_clock(struct clocksource *cs) 206 { 207 return get_tod_clock(); 208 } 209 210 static struct clocksource clocksource_tod = { 211 .name = "tod", 212 .rating = 400, 213 .read = read_tod_clock, 214 .mask = -1ULL, 215 .mult = 1000, 216 .shift = 12, 217 .flags = CLOCK_SOURCE_IS_CONTINUOUS, 218 }; 219 220 struct clocksource * __init clocksource_default_clock(void) 221 { 222 return &clocksource_tod; 223 } 224 225 void update_vsyscall_old(struct timespec *wall_time, struct timespec *wtm, 226 struct clocksource *clock, u32 mult) 227 { 228 if (clock != &clocksource_tod) 229 return; 230 231 /* Make userspace gettimeofday spin until we're done. */ 232 ++vdso_data->tb_update_count; 233 smp_wmb(); 234 vdso_data->xtime_tod_stamp = clock->cycle_last; 235 vdso_data->xtime_clock_sec = wall_time->tv_sec; 236 vdso_data->xtime_clock_nsec = wall_time->tv_nsec; 237 vdso_data->wtom_clock_sec = wtm->tv_sec; 238 vdso_data->wtom_clock_nsec = wtm->tv_nsec; 239 vdso_data->ntp_mult = mult; 240 smp_wmb(); 241 ++vdso_data->tb_update_count; 242 } 243 244 extern struct timezone sys_tz; 245 246 void update_vsyscall_tz(void) 247 { 248 /* Make userspace gettimeofday spin until we're done. */ 249 ++vdso_data->tb_update_count; 250 smp_wmb(); 251 vdso_data->tz_minuteswest = sys_tz.tz_minuteswest; 252 vdso_data->tz_dsttime = sys_tz.tz_dsttime; 253 smp_wmb(); 254 ++vdso_data->tb_update_count; 255 } 256 257 /* 258 * Initialize the TOD clock and the CPU timer of 259 * the boot cpu. 260 */ 261 void __init time_init(void) 262 { 263 /* Reset time synchronization interfaces. */ 264 etr_reset(); 265 stp_reset(); 266 267 /* request the clock comparator external interrupt */ 268 if (register_external_interrupt(0x1004, clock_comparator_interrupt)) 269 panic("Couldn't request external interrupt 0x1004"); 270 271 /* request the timing alert external interrupt */ 272 if (register_external_interrupt(0x1406, 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 /* 286 * The time is "clock". old is what we think the time is. 287 * Adjust the value by a multiple of jiffies and add the delta to ntp. 288 * "delay" is an approximation how long the synchronization took. If 289 * the time correction is positive, then "delay" is subtracted from 290 * the time difference and only the remaining part is passed to ntp. 291 */ 292 static unsigned long long adjust_time(unsigned long long old, 293 unsigned long long clock, 294 unsigned long long delay) 295 { 296 unsigned long long delta, ticks; 297 struct timex adjust; 298 299 if (clock > old) { 300 /* It is later than we thought. */ 301 delta = ticks = clock - old; 302 delta = ticks = (delta < delay) ? 0 : delta - delay; 303 delta -= do_div(ticks, CLK_TICKS_PER_JIFFY); 304 adjust.offset = ticks * (1000000 / HZ); 305 } else { 306 /* It is earlier than we thought. */ 307 delta = ticks = old - clock; 308 delta -= do_div(ticks, CLK_TICKS_PER_JIFFY); 309 delta = -delta; 310 adjust.offset = -ticks * (1000000 / HZ); 311 } 312 sched_clock_base_cc += delta; 313 if (adjust.offset != 0) { 314 pr_notice("The ETR interface has adjusted the clock " 315 "by %li microseconds\n", adjust.offset); 316 adjust.modes = ADJ_OFFSET_SINGLESHOT; 317 do_adjtimex(&adjust); 318 } 319 return delta; 320 } 321 322 static DEFINE_PER_CPU(atomic_t, clock_sync_word); 323 static DEFINE_MUTEX(clock_sync_mutex); 324 static unsigned long clock_sync_flags; 325 326 #define CLOCK_SYNC_HAS_ETR 0 327 #define CLOCK_SYNC_HAS_STP 1 328 #define CLOCK_SYNC_ETR 2 329 #define CLOCK_SYNC_STP 3 330 331 /* 332 * The synchronous get_clock function. It will write the current clock 333 * value to the clock pointer and return 0 if the clock is in sync with 334 * the external time source. If the clock mode is local it will return 335 * -EOPNOTSUPP and -EAGAIN if the clock is not in sync with the external 336 * reference. 337 */ 338 int get_sync_clock(unsigned long long *clock) 339 { 340 atomic_t *sw_ptr; 341 unsigned int sw0, sw1; 342 343 sw_ptr = &get_cpu_var(clock_sync_word); 344 sw0 = atomic_read(sw_ptr); 345 *clock = get_tod_clock(); 346 sw1 = atomic_read(sw_ptr); 347 put_cpu_var(clock_sync_word); 348 if (sw0 == sw1 && (sw0 & 0x80000000U)) 349 /* Success: time is in sync. */ 350 return 0; 351 if (!test_bit(CLOCK_SYNC_HAS_ETR, &clock_sync_flags) && 352 !test_bit(CLOCK_SYNC_HAS_STP, &clock_sync_flags)) 353 return -EOPNOTSUPP; 354 if (!test_bit(CLOCK_SYNC_ETR, &clock_sync_flags) && 355 !test_bit(CLOCK_SYNC_STP, &clock_sync_flags)) 356 return -EACCES; 357 return -EAGAIN; 358 } 359 EXPORT_SYMBOL(get_sync_clock); 360 361 /* 362 * Make get_sync_clock return -EAGAIN. 363 */ 364 static void disable_sync_clock(void *dummy) 365 { 366 atomic_t *sw_ptr = &__get_cpu_var(clock_sync_word); 367 /* 368 * Clear the in-sync bit 2^31. All get_sync_clock calls will 369 * fail until the sync bit is turned back on. In addition 370 * increase the "sequence" counter to avoid the race of an 371 * etr event and the complete recovery against get_sync_clock. 372 */ 373 atomic_clear_mask(0x80000000, sw_ptr); 374 atomic_inc(sw_ptr); 375 } 376 377 /* 378 * Make get_sync_clock return 0 again. 379 * Needs to be called from a context disabled for preemption. 380 */ 381 static void enable_sync_clock(void) 382 { 383 atomic_t *sw_ptr = &__get_cpu_var(clock_sync_word); 384 atomic_set_mask(0x80000000, sw_ptr); 385 } 386 387 /* 388 * Function to check if the clock is in sync. 389 */ 390 static inline int check_sync_clock(void) 391 { 392 atomic_t *sw_ptr; 393 int rc; 394 395 sw_ptr = &get_cpu_var(clock_sync_word); 396 rc = (atomic_read(sw_ptr) & 0x80000000U) != 0; 397 put_cpu_var(clock_sync_word); 398 return rc; 399 } 400 401 /* Single threaded workqueue used for etr and stp sync events */ 402 static struct workqueue_struct *time_sync_wq; 403 404 static void __init time_init_wq(void) 405 { 406 if (time_sync_wq) 407 return; 408 time_sync_wq = create_singlethread_workqueue("timesync"); 409 } 410 411 /* 412 * External Time Reference (ETR) code. 413 */ 414 static int etr_port0_online; 415 static int etr_port1_online; 416 static int etr_steai_available; 417 418 static int __init early_parse_etr(char *p) 419 { 420 if (strncmp(p, "off", 3) == 0) 421 etr_port0_online = etr_port1_online = 0; 422 else if (strncmp(p, "port0", 5) == 0) 423 etr_port0_online = 1; 424 else if (strncmp(p, "port1", 5) == 0) 425 etr_port1_online = 1; 426 else if (strncmp(p, "on", 2) == 0) 427 etr_port0_online = etr_port1_online = 1; 428 return 0; 429 } 430 early_param("etr", early_parse_etr); 431 432 enum etr_event { 433 ETR_EVENT_PORT0_CHANGE, 434 ETR_EVENT_PORT1_CHANGE, 435 ETR_EVENT_PORT_ALERT, 436 ETR_EVENT_SYNC_CHECK, 437 ETR_EVENT_SWITCH_LOCAL, 438 ETR_EVENT_UPDATE, 439 }; 440 441 /* 442 * Valid bit combinations of the eacr register are (x = don't care): 443 * e0 e1 dp p0 p1 ea es sl 444 * 0 0 x 0 0 0 0 0 initial, disabled state 445 * 0 0 x 0 1 1 0 0 port 1 online 446 * 0 0 x 1 0 1 0 0 port 0 online 447 * 0 0 x 1 1 1 0 0 both ports online 448 * 0 1 x 0 1 1 0 0 port 1 online and usable, ETR or PPS mode 449 * 0 1 x 0 1 1 0 1 port 1 online, usable and ETR mode 450 * 0 1 x 0 1 1 1 0 port 1 online, usable, PPS mode, in-sync 451 * 0 1 x 0 1 1 1 1 port 1 online, usable, ETR mode, in-sync 452 * 0 1 x 1 1 1 0 0 both ports online, port 1 usable 453 * 0 1 x 1 1 1 1 0 both ports online, port 1 usable, PPS mode, in-sync 454 * 0 1 x 1 1 1 1 1 both ports online, port 1 usable, ETR mode, in-sync 455 * 1 0 x 1 0 1 0 0 port 0 online and usable, ETR or PPS mode 456 * 1 0 x 1 0 1 0 1 port 0 online, usable and ETR mode 457 * 1 0 x 1 0 1 1 0 port 0 online, usable, PPS mode, in-sync 458 * 1 0 x 1 0 1 1 1 port 0 online, usable, ETR mode, in-sync 459 * 1 0 x 1 1 1 0 0 both ports online, port 0 usable 460 * 1 0 x 1 1 1 1 0 both ports online, port 0 usable, PPS mode, in-sync 461 * 1 0 x 1 1 1 1 1 both ports online, port 0 usable, ETR mode, in-sync 462 * 1 1 x 1 1 1 1 0 both ports online & usable, ETR, in-sync 463 * 1 1 x 1 1 1 1 1 both ports online & usable, ETR, in-sync 464 */ 465 static struct etr_eacr etr_eacr; 466 static u64 etr_tolec; /* time of last eacr update */ 467 static struct etr_aib etr_port0; 468 static int etr_port0_uptodate; 469 static struct etr_aib etr_port1; 470 static int etr_port1_uptodate; 471 static unsigned long etr_events; 472 static struct timer_list etr_timer; 473 474 static void etr_timeout(unsigned long dummy); 475 static void etr_work_fn(struct work_struct *work); 476 static DEFINE_MUTEX(etr_work_mutex); 477 static DECLARE_WORK(etr_work, etr_work_fn); 478 479 /* 480 * Reset ETR attachment. 481 */ 482 static void etr_reset(void) 483 { 484 etr_eacr = (struct etr_eacr) { 485 .e0 = 0, .e1 = 0, ._pad0 = 4, .dp = 0, 486 .p0 = 0, .p1 = 0, ._pad1 = 0, .ea = 0, 487 .es = 0, .sl = 0 }; 488 if (etr_setr(&etr_eacr) == 0) { 489 etr_tolec = get_tod_clock(); 490 set_bit(CLOCK_SYNC_HAS_ETR, &clock_sync_flags); 491 if (etr_port0_online && etr_port1_online) 492 set_bit(CLOCK_SYNC_ETR, &clock_sync_flags); 493 } else if (etr_port0_online || etr_port1_online) { 494 pr_warning("The real or virtual hardware system does " 495 "not provide an ETR interface\n"); 496 etr_port0_online = etr_port1_online = 0; 497 } 498 } 499 500 static int __init etr_init(void) 501 { 502 struct etr_aib aib; 503 504 if (!test_bit(CLOCK_SYNC_HAS_ETR, &clock_sync_flags)) 505 return 0; 506 time_init_wq(); 507 /* Check if this machine has the steai instruction. */ 508 if (etr_steai(&aib, ETR_STEAI_STEPPING_PORT) == 0) 509 etr_steai_available = 1; 510 setup_timer(&etr_timer, etr_timeout, 0UL); 511 if (etr_port0_online) { 512 set_bit(ETR_EVENT_PORT0_CHANGE, &etr_events); 513 queue_work(time_sync_wq, &etr_work); 514 } 515 if (etr_port1_online) { 516 set_bit(ETR_EVENT_PORT1_CHANGE, &etr_events); 517 queue_work(time_sync_wq, &etr_work); 518 } 519 return 0; 520 } 521 522 arch_initcall(etr_init); 523 524 /* 525 * Two sorts of ETR machine checks. The architecture reads: 526 * "When a machine-check niterruption occurs and if a switch-to-local or 527 * ETR-sync-check interrupt request is pending but disabled, this pending 528 * disabled interruption request is indicated and is cleared". 529 * Which means that we can get etr_switch_to_local events from the machine 530 * check handler although the interruption condition is disabled. Lovely.. 531 */ 532 533 /* 534 * Switch to local machine check. This is called when the last usable 535 * ETR port goes inactive. After switch to local the clock is not in sync. 536 */ 537 void etr_switch_to_local(void) 538 { 539 if (!etr_eacr.sl) 540 return; 541 disable_sync_clock(NULL); 542 if (!test_and_set_bit(ETR_EVENT_SWITCH_LOCAL, &etr_events)) { 543 etr_eacr.es = etr_eacr.sl = 0; 544 etr_setr(&etr_eacr); 545 queue_work(time_sync_wq, &etr_work); 546 } 547 } 548 549 /* 550 * ETR sync check machine check. This is called when the ETR OTE and the 551 * local clock OTE are farther apart than the ETR sync check tolerance. 552 * After a ETR sync check the clock is not in sync. The machine check 553 * is broadcasted to all cpus at the same time. 554 */ 555 void etr_sync_check(void) 556 { 557 if (!etr_eacr.es) 558 return; 559 disable_sync_clock(NULL); 560 if (!test_and_set_bit(ETR_EVENT_SYNC_CHECK, &etr_events)) { 561 etr_eacr.es = 0; 562 etr_setr(&etr_eacr); 563 queue_work(time_sync_wq, &etr_work); 564 } 565 } 566 567 /* 568 * ETR timing alert. There are two causes: 569 * 1) port state change, check the usability of the port 570 * 2) port alert, one of the ETR-data-validity bits (v1-v2 bits of the 571 * sldr-status word) or ETR-data word 1 (edf1) or ETR-data word 3 (edf3) 572 * or ETR-data word 4 (edf4) has changed. 573 */ 574 static void etr_timing_alert(struct etr_irq_parm *intparm) 575 { 576 if (intparm->pc0) 577 /* ETR port 0 state change. */ 578 set_bit(ETR_EVENT_PORT0_CHANGE, &etr_events); 579 if (intparm->pc1) 580 /* ETR port 1 state change. */ 581 set_bit(ETR_EVENT_PORT1_CHANGE, &etr_events); 582 if (intparm->eai) 583 /* 584 * ETR port alert on either port 0, 1 or both. 585 * Both ports are not up-to-date now. 586 */ 587 set_bit(ETR_EVENT_PORT_ALERT, &etr_events); 588 queue_work(time_sync_wq, &etr_work); 589 } 590 591 static void etr_timeout(unsigned long dummy) 592 { 593 set_bit(ETR_EVENT_UPDATE, &etr_events); 594 queue_work(time_sync_wq, &etr_work); 595 } 596 597 /* 598 * Check if the etr mode is pss. 599 */ 600 static inline int etr_mode_is_pps(struct etr_eacr eacr) 601 { 602 return eacr.es && !eacr.sl; 603 } 604 605 /* 606 * Check if the etr mode is etr. 607 */ 608 static inline int etr_mode_is_etr(struct etr_eacr eacr) 609 { 610 return eacr.es && eacr.sl; 611 } 612 613 /* 614 * Check if the port can be used for TOD synchronization. 615 * For PPS mode the port has to receive OTEs. For ETR mode 616 * the port has to receive OTEs, the ETR stepping bit has to 617 * be zero and the validity bits for data frame 1, 2, and 3 618 * have to be 1. 619 */ 620 static int etr_port_valid(struct etr_aib *aib, int port) 621 { 622 unsigned int psc; 623 624 /* Check that this port is receiving OTEs. */ 625 if (aib->tsp == 0) 626 return 0; 627 628 psc = port ? aib->esw.psc1 : aib->esw.psc0; 629 if (psc == etr_lpsc_pps_mode) 630 return 1; 631 if (psc == etr_lpsc_operational_step) 632 return !aib->esw.y && aib->slsw.v1 && 633 aib->slsw.v2 && aib->slsw.v3; 634 return 0; 635 } 636 637 /* 638 * Check if two ports are on the same network. 639 */ 640 static int etr_compare_network(struct etr_aib *aib1, struct etr_aib *aib2) 641 { 642 // FIXME: any other fields we have to compare? 643 return aib1->edf1.net_id == aib2->edf1.net_id; 644 } 645 646 /* 647 * Wrapper for etr_stei that converts physical port states 648 * to logical port states to be consistent with the output 649 * of stetr (see etr_psc vs. etr_lpsc). 650 */ 651 static void etr_steai_cv(struct etr_aib *aib, unsigned int func) 652 { 653 BUG_ON(etr_steai(aib, func) != 0); 654 /* Convert port state to logical port state. */ 655 if (aib->esw.psc0 == 1) 656 aib->esw.psc0 = 2; 657 else if (aib->esw.psc0 == 0 && aib->esw.p == 0) 658 aib->esw.psc0 = 1; 659 if (aib->esw.psc1 == 1) 660 aib->esw.psc1 = 2; 661 else if (aib->esw.psc1 == 0 && aib->esw.p == 1) 662 aib->esw.psc1 = 1; 663 } 664 665 /* 666 * Check if the aib a2 is still connected to the same attachment as 667 * aib a1, the etv values differ by one and a2 is valid. 668 */ 669 static int etr_aib_follows(struct etr_aib *a1, struct etr_aib *a2, int p) 670 { 671 int state_a1, state_a2; 672 673 /* Paranoia check: e0/e1 should better be the same. */ 674 if (a1->esw.eacr.e0 != a2->esw.eacr.e0 || 675 a1->esw.eacr.e1 != a2->esw.eacr.e1) 676 return 0; 677 678 /* Still connected to the same etr ? */ 679 state_a1 = p ? a1->esw.psc1 : a1->esw.psc0; 680 state_a2 = p ? a2->esw.psc1 : a2->esw.psc0; 681 if (state_a1 == etr_lpsc_operational_step) { 682 if (state_a2 != etr_lpsc_operational_step || 683 a1->edf1.net_id != a2->edf1.net_id || 684 a1->edf1.etr_id != a2->edf1.etr_id || 685 a1->edf1.etr_pn != a2->edf1.etr_pn) 686 return 0; 687 } else if (state_a2 != etr_lpsc_pps_mode) 688 return 0; 689 690 /* The ETV value of a2 needs to be ETV of a1 + 1. */ 691 if (a1->edf2.etv + 1 != a2->edf2.etv) 692 return 0; 693 694 if (!etr_port_valid(a2, p)) 695 return 0; 696 697 return 1; 698 } 699 700 struct clock_sync_data { 701 atomic_t cpus; 702 int in_sync; 703 unsigned long long fixup_cc; 704 int etr_port; 705 struct etr_aib *etr_aib; 706 }; 707 708 static void clock_sync_cpu(struct clock_sync_data *sync) 709 { 710 atomic_dec(&sync->cpus); 711 enable_sync_clock(); 712 /* 713 * This looks like a busy wait loop but it isn't. etr_sync_cpus 714 * is called on all other cpus while the TOD clocks is stopped. 715 * __udelay will stop the cpu on an enabled wait psw until the 716 * TOD is running again. 717 */ 718 while (sync->in_sync == 0) { 719 __udelay(1); 720 /* 721 * A different cpu changes *in_sync. Therefore use 722 * barrier() to force memory access. 723 */ 724 barrier(); 725 } 726 if (sync->in_sync != 1) 727 /* Didn't work. Clear per-cpu in sync bit again. */ 728 disable_sync_clock(NULL); 729 /* 730 * This round of TOD syncing is done. Set the clock comparator 731 * to the next tick and let the processor continue. 732 */ 733 fixup_clock_comparator(sync->fixup_cc); 734 } 735 736 /* 737 * Sync the TOD clock using the port referred to by aibp. This port 738 * has to be enabled and the other port has to be disabled. The 739 * last eacr update has to be more than 1.6 seconds in the past. 740 */ 741 static int etr_sync_clock(void *data) 742 { 743 static int first; 744 unsigned long long clock, old_clock, delay, delta; 745 struct clock_sync_data *etr_sync; 746 struct etr_aib *sync_port, *aib; 747 int port; 748 int rc; 749 750 etr_sync = data; 751 752 if (xchg(&first, 1) == 1) { 753 /* Slave */ 754 clock_sync_cpu(etr_sync); 755 return 0; 756 } 757 758 /* Wait until all other cpus entered the sync function. */ 759 while (atomic_read(&etr_sync->cpus) != 0) 760 cpu_relax(); 761 762 port = etr_sync->etr_port; 763 aib = etr_sync->etr_aib; 764 sync_port = (port == 0) ? &etr_port0 : &etr_port1; 765 enable_sync_clock(); 766 767 /* Set clock to next OTE. */ 768 __ctl_set_bit(14, 21); 769 __ctl_set_bit(0, 29); 770 clock = ((unsigned long long) (aib->edf2.etv + 1)) << 32; 771 old_clock = get_tod_clock(); 772 if (set_tod_clock(clock) == 0) { 773 __udelay(1); /* Wait for the clock to start. */ 774 __ctl_clear_bit(0, 29); 775 __ctl_clear_bit(14, 21); 776 etr_stetr(aib); 777 /* Adjust Linux timing variables. */ 778 delay = (unsigned long long) 779 (aib->edf2.etv - sync_port->edf2.etv) << 32; 780 delta = adjust_time(old_clock, clock, delay); 781 etr_sync->fixup_cc = delta; 782 fixup_clock_comparator(delta); 783 /* Verify that the clock is properly set. */ 784 if (!etr_aib_follows(sync_port, aib, port)) { 785 /* Didn't work. */ 786 disable_sync_clock(NULL); 787 etr_sync->in_sync = -EAGAIN; 788 rc = -EAGAIN; 789 } else { 790 etr_sync->in_sync = 1; 791 rc = 0; 792 } 793 } else { 794 /* Could not set the clock ?!? */ 795 __ctl_clear_bit(0, 29); 796 __ctl_clear_bit(14, 21); 797 disable_sync_clock(NULL); 798 etr_sync->in_sync = -EAGAIN; 799 rc = -EAGAIN; 800 } 801 xchg(&first, 0); 802 return rc; 803 } 804 805 static int etr_sync_clock_stop(struct etr_aib *aib, int port) 806 { 807 struct clock_sync_data etr_sync; 808 struct etr_aib *sync_port; 809 int follows; 810 int rc; 811 812 /* Check if the current aib is adjacent to the sync port aib. */ 813 sync_port = (port == 0) ? &etr_port0 : &etr_port1; 814 follows = etr_aib_follows(sync_port, aib, port); 815 memcpy(sync_port, aib, sizeof(*aib)); 816 if (!follows) 817 return -EAGAIN; 818 memset(&etr_sync, 0, sizeof(etr_sync)); 819 etr_sync.etr_aib = aib; 820 etr_sync.etr_port = port; 821 get_online_cpus(); 822 atomic_set(&etr_sync.cpus, num_online_cpus() - 1); 823 rc = stop_machine(etr_sync_clock, &etr_sync, cpu_online_mask); 824 put_online_cpus(); 825 return rc; 826 } 827 828 /* 829 * Handle the immediate effects of the different events. 830 * The port change event is used for online/offline changes. 831 */ 832 static struct etr_eacr etr_handle_events(struct etr_eacr eacr) 833 { 834 if (test_and_clear_bit(ETR_EVENT_SYNC_CHECK, &etr_events)) 835 eacr.es = 0; 836 if (test_and_clear_bit(ETR_EVENT_SWITCH_LOCAL, &etr_events)) 837 eacr.es = eacr.sl = 0; 838 if (test_and_clear_bit(ETR_EVENT_PORT_ALERT, &etr_events)) 839 etr_port0_uptodate = etr_port1_uptodate = 0; 840 841 if (test_and_clear_bit(ETR_EVENT_PORT0_CHANGE, &etr_events)) { 842 if (eacr.e0) 843 /* 844 * Port change of an enabled port. We have to 845 * assume that this can have caused an stepping 846 * port switch. 847 */ 848 etr_tolec = get_tod_clock(); 849 eacr.p0 = etr_port0_online; 850 if (!eacr.p0) 851 eacr.e0 = 0; 852 etr_port0_uptodate = 0; 853 } 854 if (test_and_clear_bit(ETR_EVENT_PORT1_CHANGE, &etr_events)) { 855 if (eacr.e1) 856 /* 857 * Port change of an enabled port. We have to 858 * assume that this can have caused an stepping 859 * port switch. 860 */ 861 etr_tolec = get_tod_clock(); 862 eacr.p1 = etr_port1_online; 863 if (!eacr.p1) 864 eacr.e1 = 0; 865 etr_port1_uptodate = 0; 866 } 867 clear_bit(ETR_EVENT_UPDATE, &etr_events); 868 return eacr; 869 } 870 871 /* 872 * Set up a timer that expires after the etr_tolec + 1.6 seconds if 873 * one of the ports needs an update. 874 */ 875 static void etr_set_tolec_timeout(unsigned long long now) 876 { 877 unsigned long micros; 878 879 if ((!etr_eacr.p0 || etr_port0_uptodate) && 880 (!etr_eacr.p1 || etr_port1_uptodate)) 881 return; 882 micros = (now > etr_tolec) ? ((now - etr_tolec) >> 12) : 0; 883 micros = (micros > 1600000) ? 0 : 1600000 - micros; 884 mod_timer(&etr_timer, jiffies + (micros * HZ) / 1000000 + 1); 885 } 886 887 /* 888 * Set up a time that expires after 1/2 second. 889 */ 890 static void etr_set_sync_timeout(void) 891 { 892 mod_timer(&etr_timer, jiffies + HZ/2); 893 } 894 895 /* 896 * Update the aib information for one or both ports. 897 */ 898 static struct etr_eacr etr_handle_update(struct etr_aib *aib, 899 struct etr_eacr eacr) 900 { 901 /* With both ports disabled the aib information is useless. */ 902 if (!eacr.e0 && !eacr.e1) 903 return eacr; 904 905 /* Update port0 or port1 with aib stored in etr_work_fn. */ 906 if (aib->esw.q == 0) { 907 /* Information for port 0 stored. */ 908 if (eacr.p0 && !etr_port0_uptodate) { 909 etr_port0 = *aib; 910 if (etr_port0_online) 911 etr_port0_uptodate = 1; 912 } 913 } else { 914 /* Information for port 1 stored. */ 915 if (eacr.p1 && !etr_port1_uptodate) { 916 etr_port1 = *aib; 917 if (etr_port0_online) 918 etr_port1_uptodate = 1; 919 } 920 } 921 922 /* 923 * Do not try to get the alternate port aib if the clock 924 * is not in sync yet. 925 */ 926 if (!eacr.es || !check_sync_clock()) 927 return eacr; 928 929 /* 930 * If steai is available we can get the information about 931 * the other port immediately. If only stetr is available the 932 * data-port bit toggle has to be used. 933 */ 934 if (etr_steai_available) { 935 if (eacr.p0 && !etr_port0_uptodate) { 936 etr_steai_cv(&etr_port0, ETR_STEAI_PORT_0); 937 etr_port0_uptodate = 1; 938 } 939 if (eacr.p1 && !etr_port1_uptodate) { 940 etr_steai_cv(&etr_port1, ETR_STEAI_PORT_1); 941 etr_port1_uptodate = 1; 942 } 943 } else { 944 /* 945 * One port was updated above, if the other 946 * port is not uptodate toggle dp bit. 947 */ 948 if ((eacr.p0 && !etr_port0_uptodate) || 949 (eacr.p1 && !etr_port1_uptodate)) 950 eacr.dp ^= 1; 951 else 952 eacr.dp = 0; 953 } 954 return eacr; 955 } 956 957 /* 958 * Write new etr control register if it differs from the current one. 959 * Return 1 if etr_tolec has been updated as well. 960 */ 961 static void etr_update_eacr(struct etr_eacr eacr) 962 { 963 int dp_changed; 964 965 if (memcmp(&etr_eacr, &eacr, sizeof(eacr)) == 0) 966 /* No change, return. */ 967 return; 968 /* 969 * The disable of an active port of the change of the data port 970 * bit can/will cause a change in the data port. 971 */ 972 dp_changed = etr_eacr.e0 > eacr.e0 || etr_eacr.e1 > eacr.e1 || 973 (etr_eacr.dp ^ eacr.dp) != 0; 974 etr_eacr = eacr; 975 etr_setr(&etr_eacr); 976 if (dp_changed) 977 etr_tolec = get_tod_clock(); 978 } 979 980 /* 981 * ETR work. In this function you'll find the main logic. In 982 * particular this is the only function that calls etr_update_eacr(), 983 * it "controls" the etr control register. 984 */ 985 static void etr_work_fn(struct work_struct *work) 986 { 987 unsigned long long now; 988 struct etr_eacr eacr; 989 struct etr_aib aib; 990 int sync_port; 991 992 /* prevent multiple execution. */ 993 mutex_lock(&etr_work_mutex); 994 995 /* Create working copy of etr_eacr. */ 996 eacr = etr_eacr; 997 998 /* Check for the different events and their immediate effects. */ 999 eacr = etr_handle_events(eacr); 1000 1001 /* Check if ETR is supposed to be active. */ 1002 eacr.ea = eacr.p0 || eacr.p1; 1003 if (!eacr.ea) { 1004 /* Both ports offline. Reset everything. */ 1005 eacr.dp = eacr.es = eacr.sl = 0; 1006 on_each_cpu(disable_sync_clock, NULL, 1); 1007 del_timer_sync(&etr_timer); 1008 etr_update_eacr(eacr); 1009 goto out_unlock; 1010 } 1011 1012 /* Store aib to get the current ETR status word. */ 1013 BUG_ON(etr_stetr(&aib) != 0); 1014 etr_port0.esw = etr_port1.esw = aib.esw; /* Copy status word. */ 1015 now = get_tod_clock(); 1016 1017 /* 1018 * Update the port information if the last stepping port change 1019 * or data port change is older than 1.6 seconds. 1020 */ 1021 if (now >= etr_tolec + (1600000 << 12)) 1022 eacr = etr_handle_update(&aib, eacr); 1023 1024 /* 1025 * Select ports to enable. The preferred synchronization mode is PPS. 1026 * If a port can be enabled depends on a number of things: 1027 * 1) The port needs to be online and uptodate. A port is not 1028 * disabled just because it is not uptodate, but it is only 1029 * enabled if it is uptodate. 1030 * 2) The port needs to have the same mode (pps / etr). 1031 * 3) The port needs to be usable -> etr_port_valid() == 1 1032 * 4) To enable the second port the clock needs to be in sync. 1033 * 5) If both ports are useable and are ETR ports, the network id 1034 * has to be the same. 1035 * The eacr.sl bit is used to indicate etr mode vs. pps mode. 1036 */ 1037 if (eacr.p0 && aib.esw.psc0 == etr_lpsc_pps_mode) { 1038 eacr.sl = 0; 1039 eacr.e0 = 1; 1040 if (!etr_mode_is_pps(etr_eacr)) 1041 eacr.es = 0; 1042 if (!eacr.es || !eacr.p1 || aib.esw.psc1 != etr_lpsc_pps_mode) 1043 eacr.e1 = 0; 1044 // FIXME: uptodate checks ? 1045 else if (etr_port0_uptodate && etr_port1_uptodate) 1046 eacr.e1 = 1; 1047 sync_port = (etr_port0_uptodate && 1048 etr_port_valid(&etr_port0, 0)) ? 0 : -1; 1049 } else if (eacr.p1 && aib.esw.psc1 == etr_lpsc_pps_mode) { 1050 eacr.sl = 0; 1051 eacr.e0 = 0; 1052 eacr.e1 = 1; 1053 if (!etr_mode_is_pps(etr_eacr)) 1054 eacr.es = 0; 1055 sync_port = (etr_port1_uptodate && 1056 etr_port_valid(&etr_port1, 1)) ? 1 : -1; 1057 } else if (eacr.p0 && aib.esw.psc0 == etr_lpsc_operational_step) { 1058 eacr.sl = 1; 1059 eacr.e0 = 1; 1060 if (!etr_mode_is_etr(etr_eacr)) 1061 eacr.es = 0; 1062 if (!eacr.es || !eacr.p1 || 1063 aib.esw.psc1 != etr_lpsc_operational_alt) 1064 eacr.e1 = 0; 1065 else if (etr_port0_uptodate && etr_port1_uptodate && 1066 etr_compare_network(&etr_port0, &etr_port1)) 1067 eacr.e1 = 1; 1068 sync_port = (etr_port0_uptodate && 1069 etr_port_valid(&etr_port0, 0)) ? 0 : -1; 1070 } else if (eacr.p1 && aib.esw.psc1 == etr_lpsc_operational_step) { 1071 eacr.sl = 1; 1072 eacr.e0 = 0; 1073 eacr.e1 = 1; 1074 if (!etr_mode_is_etr(etr_eacr)) 1075 eacr.es = 0; 1076 sync_port = (etr_port1_uptodate && 1077 etr_port_valid(&etr_port1, 1)) ? 1 : -1; 1078 } else { 1079 /* Both ports not usable. */ 1080 eacr.es = eacr.sl = 0; 1081 sync_port = -1; 1082 } 1083 1084 /* 1085 * If the clock is in sync just update the eacr and return. 1086 * If there is no valid sync port wait for a port update. 1087 */ 1088 if ((eacr.es && check_sync_clock()) || sync_port < 0) { 1089 etr_update_eacr(eacr); 1090 etr_set_tolec_timeout(now); 1091 goto out_unlock; 1092 } 1093 1094 /* 1095 * Prepare control register for clock syncing 1096 * (reset data port bit, set sync check control. 1097 */ 1098 eacr.dp = 0; 1099 eacr.es = 1; 1100 1101 /* 1102 * Update eacr and try to synchronize the clock. If the update 1103 * of eacr caused a stepping port switch (or if we have to 1104 * assume that a stepping port switch has occurred) or the 1105 * clock syncing failed, reset the sync check control bit 1106 * and set up a timer to try again after 0.5 seconds 1107 */ 1108 etr_update_eacr(eacr); 1109 if (now < etr_tolec + (1600000 << 12) || 1110 etr_sync_clock_stop(&aib, sync_port) != 0) { 1111 /* Sync failed. Try again in 1/2 second. */ 1112 eacr.es = 0; 1113 etr_update_eacr(eacr); 1114 etr_set_sync_timeout(); 1115 } else 1116 etr_set_tolec_timeout(now); 1117 out_unlock: 1118 mutex_unlock(&etr_work_mutex); 1119 } 1120 1121 /* 1122 * Sysfs interface functions 1123 */ 1124 static struct bus_type etr_subsys = { 1125 .name = "etr", 1126 .dev_name = "etr", 1127 }; 1128 1129 static struct device etr_port0_dev = { 1130 .id = 0, 1131 .bus = &etr_subsys, 1132 }; 1133 1134 static struct device etr_port1_dev = { 1135 .id = 1, 1136 .bus = &etr_subsys, 1137 }; 1138 1139 /* 1140 * ETR subsys attributes 1141 */ 1142 static ssize_t etr_stepping_port_show(struct device *dev, 1143 struct device_attribute *attr, 1144 char *buf) 1145 { 1146 return sprintf(buf, "%i\n", etr_port0.esw.p); 1147 } 1148 1149 static DEVICE_ATTR(stepping_port, 0400, etr_stepping_port_show, NULL); 1150 1151 static ssize_t etr_stepping_mode_show(struct device *dev, 1152 struct device_attribute *attr, 1153 char *buf) 1154 { 1155 char *mode_str; 1156 1157 if (etr_mode_is_pps(etr_eacr)) 1158 mode_str = "pps"; 1159 else if (etr_mode_is_etr(etr_eacr)) 1160 mode_str = "etr"; 1161 else 1162 mode_str = "local"; 1163 return sprintf(buf, "%s\n", mode_str); 1164 } 1165 1166 static DEVICE_ATTR(stepping_mode, 0400, etr_stepping_mode_show, NULL); 1167 1168 /* 1169 * ETR port attributes 1170 */ 1171 static inline struct etr_aib *etr_aib_from_dev(struct device *dev) 1172 { 1173 if (dev == &etr_port0_dev) 1174 return etr_port0_online ? &etr_port0 : NULL; 1175 else 1176 return etr_port1_online ? &etr_port1 : NULL; 1177 } 1178 1179 static ssize_t etr_online_show(struct device *dev, 1180 struct device_attribute *attr, 1181 char *buf) 1182 { 1183 unsigned int online; 1184 1185 online = (dev == &etr_port0_dev) ? etr_port0_online : etr_port1_online; 1186 return sprintf(buf, "%i\n", online); 1187 } 1188 1189 static ssize_t etr_online_store(struct device *dev, 1190 struct device_attribute *attr, 1191 const char *buf, size_t count) 1192 { 1193 unsigned int value; 1194 1195 value = simple_strtoul(buf, NULL, 0); 1196 if (value != 0 && value != 1) 1197 return -EINVAL; 1198 if (!test_bit(CLOCK_SYNC_HAS_ETR, &clock_sync_flags)) 1199 return -EOPNOTSUPP; 1200 mutex_lock(&clock_sync_mutex); 1201 if (dev == &etr_port0_dev) { 1202 if (etr_port0_online == value) 1203 goto out; /* Nothing to do. */ 1204 etr_port0_online = value; 1205 if (etr_port0_online && etr_port1_online) 1206 set_bit(CLOCK_SYNC_ETR, &clock_sync_flags); 1207 else 1208 clear_bit(CLOCK_SYNC_ETR, &clock_sync_flags); 1209 set_bit(ETR_EVENT_PORT0_CHANGE, &etr_events); 1210 queue_work(time_sync_wq, &etr_work); 1211 } else { 1212 if (etr_port1_online == value) 1213 goto out; /* Nothing to do. */ 1214 etr_port1_online = value; 1215 if (etr_port0_online && etr_port1_online) 1216 set_bit(CLOCK_SYNC_ETR, &clock_sync_flags); 1217 else 1218 clear_bit(CLOCK_SYNC_ETR, &clock_sync_flags); 1219 set_bit(ETR_EVENT_PORT1_CHANGE, &etr_events); 1220 queue_work(time_sync_wq, &etr_work); 1221 } 1222 out: 1223 mutex_unlock(&clock_sync_mutex); 1224 return count; 1225 } 1226 1227 static DEVICE_ATTR(online, 0600, etr_online_show, etr_online_store); 1228 1229 static ssize_t etr_stepping_control_show(struct device *dev, 1230 struct device_attribute *attr, 1231 char *buf) 1232 { 1233 return sprintf(buf, "%i\n", (dev == &etr_port0_dev) ? 1234 etr_eacr.e0 : etr_eacr.e1); 1235 } 1236 1237 static DEVICE_ATTR(stepping_control, 0400, etr_stepping_control_show, NULL); 1238 1239 static ssize_t etr_mode_code_show(struct device *dev, 1240 struct device_attribute *attr, char *buf) 1241 { 1242 if (!etr_port0_online && !etr_port1_online) 1243 /* Status word is not uptodate if both ports are offline. */ 1244 return -ENODATA; 1245 return sprintf(buf, "%i\n", (dev == &etr_port0_dev) ? 1246 etr_port0.esw.psc0 : etr_port0.esw.psc1); 1247 } 1248 1249 static DEVICE_ATTR(state_code, 0400, etr_mode_code_show, NULL); 1250 1251 static ssize_t etr_untuned_show(struct device *dev, 1252 struct device_attribute *attr, char *buf) 1253 { 1254 struct etr_aib *aib = etr_aib_from_dev(dev); 1255 1256 if (!aib || !aib->slsw.v1) 1257 return -ENODATA; 1258 return sprintf(buf, "%i\n", aib->edf1.u); 1259 } 1260 1261 static DEVICE_ATTR(untuned, 0400, etr_untuned_show, NULL); 1262 1263 static ssize_t etr_network_id_show(struct device *dev, 1264 struct device_attribute *attr, char *buf) 1265 { 1266 struct etr_aib *aib = etr_aib_from_dev(dev); 1267 1268 if (!aib || !aib->slsw.v1) 1269 return -ENODATA; 1270 return sprintf(buf, "%i\n", aib->edf1.net_id); 1271 } 1272 1273 static DEVICE_ATTR(network, 0400, etr_network_id_show, NULL); 1274 1275 static ssize_t etr_id_show(struct device *dev, 1276 struct device_attribute *attr, char *buf) 1277 { 1278 struct etr_aib *aib = etr_aib_from_dev(dev); 1279 1280 if (!aib || !aib->slsw.v1) 1281 return -ENODATA; 1282 return sprintf(buf, "%i\n", aib->edf1.etr_id); 1283 } 1284 1285 static DEVICE_ATTR(id, 0400, etr_id_show, NULL); 1286 1287 static ssize_t etr_port_number_show(struct device *dev, 1288 struct device_attribute *attr, char *buf) 1289 { 1290 struct etr_aib *aib = etr_aib_from_dev(dev); 1291 1292 if (!aib || !aib->slsw.v1) 1293 return -ENODATA; 1294 return sprintf(buf, "%i\n", aib->edf1.etr_pn); 1295 } 1296 1297 static DEVICE_ATTR(port, 0400, etr_port_number_show, NULL); 1298 1299 static ssize_t etr_coupled_show(struct device *dev, 1300 struct device_attribute *attr, char *buf) 1301 { 1302 struct etr_aib *aib = etr_aib_from_dev(dev); 1303 1304 if (!aib || !aib->slsw.v3) 1305 return -ENODATA; 1306 return sprintf(buf, "%i\n", aib->edf3.c); 1307 } 1308 1309 static DEVICE_ATTR(coupled, 0400, etr_coupled_show, NULL); 1310 1311 static ssize_t etr_local_time_show(struct device *dev, 1312 struct device_attribute *attr, char *buf) 1313 { 1314 struct etr_aib *aib = etr_aib_from_dev(dev); 1315 1316 if (!aib || !aib->slsw.v3) 1317 return -ENODATA; 1318 return sprintf(buf, "%i\n", aib->edf3.blto); 1319 } 1320 1321 static DEVICE_ATTR(local_time, 0400, etr_local_time_show, NULL); 1322 1323 static ssize_t etr_utc_offset_show(struct device *dev, 1324 struct device_attribute *attr, char *buf) 1325 { 1326 struct etr_aib *aib = etr_aib_from_dev(dev); 1327 1328 if (!aib || !aib->slsw.v3) 1329 return -ENODATA; 1330 return sprintf(buf, "%i\n", aib->edf3.buo); 1331 } 1332 1333 static DEVICE_ATTR(utc_offset, 0400, etr_utc_offset_show, NULL); 1334 1335 static struct device_attribute *etr_port_attributes[] = { 1336 &dev_attr_online, 1337 &dev_attr_stepping_control, 1338 &dev_attr_state_code, 1339 &dev_attr_untuned, 1340 &dev_attr_network, 1341 &dev_attr_id, 1342 &dev_attr_port, 1343 &dev_attr_coupled, 1344 &dev_attr_local_time, 1345 &dev_attr_utc_offset, 1346 NULL 1347 }; 1348 1349 static int __init etr_register_port(struct device *dev) 1350 { 1351 struct device_attribute **attr; 1352 int rc; 1353 1354 rc = device_register(dev); 1355 if (rc) 1356 goto out; 1357 for (attr = etr_port_attributes; *attr; attr++) { 1358 rc = device_create_file(dev, *attr); 1359 if (rc) 1360 goto out_unreg; 1361 } 1362 return 0; 1363 out_unreg: 1364 for (; attr >= etr_port_attributes; attr--) 1365 device_remove_file(dev, *attr); 1366 device_unregister(dev); 1367 out: 1368 return rc; 1369 } 1370 1371 static void __init etr_unregister_port(struct device *dev) 1372 { 1373 struct device_attribute **attr; 1374 1375 for (attr = etr_port_attributes; *attr; attr++) 1376 device_remove_file(dev, *attr); 1377 device_unregister(dev); 1378 } 1379 1380 static int __init etr_init_sysfs(void) 1381 { 1382 int rc; 1383 1384 rc = subsys_system_register(&etr_subsys, NULL); 1385 if (rc) 1386 goto out; 1387 rc = device_create_file(etr_subsys.dev_root, &dev_attr_stepping_port); 1388 if (rc) 1389 goto out_unreg_subsys; 1390 rc = device_create_file(etr_subsys.dev_root, &dev_attr_stepping_mode); 1391 if (rc) 1392 goto out_remove_stepping_port; 1393 rc = etr_register_port(&etr_port0_dev); 1394 if (rc) 1395 goto out_remove_stepping_mode; 1396 rc = etr_register_port(&etr_port1_dev); 1397 if (rc) 1398 goto out_remove_port0; 1399 return 0; 1400 1401 out_remove_port0: 1402 etr_unregister_port(&etr_port0_dev); 1403 out_remove_stepping_mode: 1404 device_remove_file(etr_subsys.dev_root, &dev_attr_stepping_mode); 1405 out_remove_stepping_port: 1406 device_remove_file(etr_subsys.dev_root, &dev_attr_stepping_port); 1407 out_unreg_subsys: 1408 bus_unregister(&etr_subsys); 1409 out: 1410 return rc; 1411 } 1412 1413 device_initcall(etr_init_sysfs); 1414 1415 /* 1416 * Server Time Protocol (STP) code. 1417 */ 1418 static int stp_online; 1419 static struct stp_sstpi stp_info; 1420 static void *stp_page; 1421 1422 static void stp_work_fn(struct work_struct *work); 1423 static DEFINE_MUTEX(stp_work_mutex); 1424 static DECLARE_WORK(stp_work, stp_work_fn); 1425 static struct timer_list stp_timer; 1426 1427 static int __init early_parse_stp(char *p) 1428 { 1429 if (strncmp(p, "off", 3) == 0) 1430 stp_online = 0; 1431 else if (strncmp(p, "on", 2) == 0) 1432 stp_online = 1; 1433 return 0; 1434 } 1435 early_param("stp", early_parse_stp); 1436 1437 /* 1438 * Reset STP attachment. 1439 */ 1440 static void __init stp_reset(void) 1441 { 1442 int rc; 1443 1444 stp_page = (void *) get_zeroed_page(GFP_ATOMIC); 1445 rc = chsc_sstpc(stp_page, STP_OP_CTRL, 0x0000); 1446 if (rc == 0) 1447 set_bit(CLOCK_SYNC_HAS_STP, &clock_sync_flags); 1448 else if (stp_online) { 1449 pr_warning("The real or virtual hardware system does " 1450 "not provide an STP interface\n"); 1451 free_page((unsigned long) stp_page); 1452 stp_page = NULL; 1453 stp_online = 0; 1454 } 1455 } 1456 1457 static void stp_timeout(unsigned long dummy) 1458 { 1459 queue_work(time_sync_wq, &stp_work); 1460 } 1461 1462 static int __init stp_init(void) 1463 { 1464 if (!test_bit(CLOCK_SYNC_HAS_STP, &clock_sync_flags)) 1465 return 0; 1466 setup_timer(&stp_timer, stp_timeout, 0UL); 1467 time_init_wq(); 1468 if (!stp_online) 1469 return 0; 1470 queue_work(time_sync_wq, &stp_work); 1471 return 0; 1472 } 1473 1474 arch_initcall(stp_init); 1475 1476 /* 1477 * STP timing alert. There are three causes: 1478 * 1) timing status change 1479 * 2) link availability change 1480 * 3) time control parameter change 1481 * In all three cases we are only interested in the clock source state. 1482 * If a STP clock source is now available use it. 1483 */ 1484 static void stp_timing_alert(struct stp_irq_parm *intparm) 1485 { 1486 if (intparm->tsc || intparm->lac || intparm->tcpc) 1487 queue_work(time_sync_wq, &stp_work); 1488 } 1489 1490 /* 1491 * STP sync check machine check. This is called when the timing state 1492 * changes from the synchronized state to the unsynchronized state. 1493 * After a STP sync check the clock is not in sync. The machine check 1494 * is broadcasted to all cpus at the same time. 1495 */ 1496 void stp_sync_check(void) 1497 { 1498 disable_sync_clock(NULL); 1499 queue_work(time_sync_wq, &stp_work); 1500 } 1501 1502 /* 1503 * STP island condition machine check. This is called when an attached 1504 * server attempts to communicate over an STP link and the servers 1505 * have matching CTN ids and have a valid stratum-1 configuration 1506 * but the configurations do not match. 1507 */ 1508 void stp_island_check(void) 1509 { 1510 disable_sync_clock(NULL); 1511 queue_work(time_sync_wq, &stp_work); 1512 } 1513 1514 1515 static int stp_sync_clock(void *data) 1516 { 1517 static int first; 1518 unsigned long long old_clock, delta; 1519 struct clock_sync_data *stp_sync; 1520 int rc; 1521 1522 stp_sync = data; 1523 1524 if (xchg(&first, 1) == 1) { 1525 /* Slave */ 1526 clock_sync_cpu(stp_sync); 1527 return 0; 1528 } 1529 1530 /* Wait until all other cpus entered the sync function. */ 1531 while (atomic_read(&stp_sync->cpus) != 0) 1532 cpu_relax(); 1533 1534 enable_sync_clock(); 1535 1536 rc = 0; 1537 if (stp_info.todoff[0] || stp_info.todoff[1] || 1538 stp_info.todoff[2] || stp_info.todoff[3] || 1539 stp_info.tmd != 2) { 1540 old_clock = get_tod_clock(); 1541 rc = chsc_sstpc(stp_page, STP_OP_SYNC, 0); 1542 if (rc == 0) { 1543 delta = adjust_time(old_clock, get_tod_clock(), 0); 1544 fixup_clock_comparator(delta); 1545 rc = chsc_sstpi(stp_page, &stp_info, 1546 sizeof(struct stp_sstpi)); 1547 if (rc == 0 && stp_info.tmd != 2) 1548 rc = -EAGAIN; 1549 } 1550 } 1551 if (rc) { 1552 disable_sync_clock(NULL); 1553 stp_sync->in_sync = -EAGAIN; 1554 } else 1555 stp_sync->in_sync = 1; 1556 xchg(&first, 0); 1557 return 0; 1558 } 1559 1560 /* 1561 * STP work. Check for the STP state and take over the clock 1562 * synchronization if the STP clock source is usable. 1563 */ 1564 static void stp_work_fn(struct work_struct *work) 1565 { 1566 struct clock_sync_data stp_sync; 1567 int rc; 1568 1569 /* prevent multiple execution. */ 1570 mutex_lock(&stp_work_mutex); 1571 1572 if (!stp_online) { 1573 chsc_sstpc(stp_page, STP_OP_CTRL, 0x0000); 1574 del_timer_sync(&stp_timer); 1575 goto out_unlock; 1576 } 1577 1578 rc = chsc_sstpc(stp_page, STP_OP_CTRL, 0xb0e0); 1579 if (rc) 1580 goto out_unlock; 1581 1582 rc = chsc_sstpi(stp_page, &stp_info, sizeof(struct stp_sstpi)); 1583 if (rc || stp_info.c == 0) 1584 goto out_unlock; 1585 1586 /* Skip synchronization if the clock is already in sync. */ 1587 if (check_sync_clock()) 1588 goto out_unlock; 1589 1590 memset(&stp_sync, 0, sizeof(stp_sync)); 1591 get_online_cpus(); 1592 atomic_set(&stp_sync.cpus, num_online_cpus() - 1); 1593 stop_machine(stp_sync_clock, &stp_sync, cpu_online_mask); 1594 put_online_cpus(); 1595 1596 if (!check_sync_clock()) 1597 /* 1598 * There is a usable clock but the synchonization failed. 1599 * Retry after a second. 1600 */ 1601 mod_timer(&stp_timer, jiffies + HZ); 1602 1603 out_unlock: 1604 mutex_unlock(&stp_work_mutex); 1605 } 1606 1607 /* 1608 * STP subsys sysfs interface functions 1609 */ 1610 static struct bus_type stp_subsys = { 1611 .name = "stp", 1612 .dev_name = "stp", 1613 }; 1614 1615 static ssize_t stp_ctn_id_show(struct device *dev, 1616 struct device_attribute *attr, 1617 char *buf) 1618 { 1619 if (!stp_online) 1620 return -ENODATA; 1621 return sprintf(buf, "%016llx\n", 1622 *(unsigned long long *) stp_info.ctnid); 1623 } 1624 1625 static DEVICE_ATTR(ctn_id, 0400, stp_ctn_id_show, NULL); 1626 1627 static ssize_t stp_ctn_type_show(struct device *dev, 1628 struct device_attribute *attr, 1629 char *buf) 1630 { 1631 if (!stp_online) 1632 return -ENODATA; 1633 return sprintf(buf, "%i\n", stp_info.ctn); 1634 } 1635 1636 static DEVICE_ATTR(ctn_type, 0400, stp_ctn_type_show, NULL); 1637 1638 static ssize_t stp_dst_offset_show(struct device *dev, 1639 struct device_attribute *attr, 1640 char *buf) 1641 { 1642 if (!stp_online || !(stp_info.vbits & 0x2000)) 1643 return -ENODATA; 1644 return sprintf(buf, "%i\n", (int)(s16) stp_info.dsto); 1645 } 1646 1647 static DEVICE_ATTR(dst_offset, 0400, stp_dst_offset_show, NULL); 1648 1649 static ssize_t stp_leap_seconds_show(struct device *dev, 1650 struct device_attribute *attr, 1651 char *buf) 1652 { 1653 if (!stp_online || !(stp_info.vbits & 0x8000)) 1654 return -ENODATA; 1655 return sprintf(buf, "%i\n", (int)(s16) stp_info.leaps); 1656 } 1657 1658 static DEVICE_ATTR(leap_seconds, 0400, stp_leap_seconds_show, NULL); 1659 1660 static ssize_t stp_stratum_show(struct device *dev, 1661 struct device_attribute *attr, 1662 char *buf) 1663 { 1664 if (!stp_online) 1665 return -ENODATA; 1666 return sprintf(buf, "%i\n", (int)(s16) stp_info.stratum); 1667 } 1668 1669 static DEVICE_ATTR(stratum, 0400, stp_stratum_show, NULL); 1670 1671 static ssize_t stp_time_offset_show(struct device *dev, 1672 struct device_attribute *attr, 1673 char *buf) 1674 { 1675 if (!stp_online || !(stp_info.vbits & 0x0800)) 1676 return -ENODATA; 1677 return sprintf(buf, "%i\n", (int) stp_info.tto); 1678 } 1679 1680 static DEVICE_ATTR(time_offset, 0400, stp_time_offset_show, NULL); 1681 1682 static ssize_t stp_time_zone_offset_show(struct device *dev, 1683 struct device_attribute *attr, 1684 char *buf) 1685 { 1686 if (!stp_online || !(stp_info.vbits & 0x4000)) 1687 return -ENODATA; 1688 return sprintf(buf, "%i\n", (int)(s16) stp_info.tzo); 1689 } 1690 1691 static DEVICE_ATTR(time_zone_offset, 0400, 1692 stp_time_zone_offset_show, NULL); 1693 1694 static ssize_t stp_timing_mode_show(struct device *dev, 1695 struct device_attribute *attr, 1696 char *buf) 1697 { 1698 if (!stp_online) 1699 return -ENODATA; 1700 return sprintf(buf, "%i\n", stp_info.tmd); 1701 } 1702 1703 static DEVICE_ATTR(timing_mode, 0400, stp_timing_mode_show, NULL); 1704 1705 static ssize_t stp_timing_state_show(struct device *dev, 1706 struct device_attribute *attr, 1707 char *buf) 1708 { 1709 if (!stp_online) 1710 return -ENODATA; 1711 return sprintf(buf, "%i\n", stp_info.tst); 1712 } 1713 1714 static DEVICE_ATTR(timing_state, 0400, stp_timing_state_show, NULL); 1715 1716 static ssize_t stp_online_show(struct device *dev, 1717 struct device_attribute *attr, 1718 char *buf) 1719 { 1720 return sprintf(buf, "%i\n", stp_online); 1721 } 1722 1723 static ssize_t stp_online_store(struct device *dev, 1724 struct device_attribute *attr, 1725 const char *buf, size_t count) 1726 { 1727 unsigned int value; 1728 1729 value = simple_strtoul(buf, NULL, 0); 1730 if (value != 0 && value != 1) 1731 return -EINVAL; 1732 if (!test_bit(CLOCK_SYNC_HAS_STP, &clock_sync_flags)) 1733 return -EOPNOTSUPP; 1734 mutex_lock(&clock_sync_mutex); 1735 stp_online = value; 1736 if (stp_online) 1737 set_bit(CLOCK_SYNC_STP, &clock_sync_flags); 1738 else 1739 clear_bit(CLOCK_SYNC_STP, &clock_sync_flags); 1740 queue_work(time_sync_wq, &stp_work); 1741 mutex_unlock(&clock_sync_mutex); 1742 return count; 1743 } 1744 1745 /* 1746 * Can't use DEVICE_ATTR because the attribute should be named 1747 * stp/online but dev_attr_online already exists in this file .. 1748 */ 1749 static struct device_attribute dev_attr_stp_online = { 1750 .attr = { .name = "online", .mode = 0600 }, 1751 .show = stp_online_show, 1752 .store = stp_online_store, 1753 }; 1754 1755 static struct device_attribute *stp_attributes[] = { 1756 &dev_attr_ctn_id, 1757 &dev_attr_ctn_type, 1758 &dev_attr_dst_offset, 1759 &dev_attr_leap_seconds, 1760 &dev_attr_stp_online, 1761 &dev_attr_stratum, 1762 &dev_attr_time_offset, 1763 &dev_attr_time_zone_offset, 1764 &dev_attr_timing_mode, 1765 &dev_attr_timing_state, 1766 NULL 1767 }; 1768 1769 static int __init stp_init_sysfs(void) 1770 { 1771 struct device_attribute **attr; 1772 int rc; 1773 1774 rc = subsys_system_register(&stp_subsys, NULL); 1775 if (rc) 1776 goto out; 1777 for (attr = stp_attributes; *attr; attr++) { 1778 rc = device_create_file(stp_subsys.dev_root, *attr); 1779 if (rc) 1780 goto out_unreg; 1781 } 1782 return 0; 1783 out_unreg: 1784 for (; attr >= stp_attributes; attr--) 1785 device_remove_file(stp_subsys.dev_root, *attr); 1786 bus_unregister(&stp_subsys); 1787 out: 1788 return rc; 1789 } 1790 1791 device_initcall(stp_init_sysfs); 1792