1 /* 2 * Copyright (c) 2005 The DragonFly Project. All rights reserved. 3 * 4 * This code is derived from software contributed to The DragonFly Project 5 * by Matthew Dillon <dillon@backplane.com> 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in 15 * the documentation and/or other materials provided with the 16 * distribution. 17 * 3. Neither the name of The DragonFly Project nor the names of its 18 * contributors may be used to endorse or promote products derived 19 * from this software without specific, prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 22 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 23 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 24 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 25 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 26 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, 27 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 28 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 29 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 30 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 31 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 /* 35 * Generic cputimer - access to a reliable, free-running counter. 36 */ 37 38 #include <sys/param.h> 39 #include <sys/kernel.h> 40 #include <sys/systm.h> 41 #include <sys/thread.h> 42 #include <sys/globaldata.h> 43 #include <sys/serialize.h> 44 #include <sys/systimer.h> 45 #include <sys/sysctl.h> 46 #include <sys/thread2.h> 47 48 extern void pcpu_timer_process(void); 49 extern void pcpu_timer_process_frame(struct intrframe *); 50 51 static sysclock_t dummy_cputimer_count(void); 52 53 static struct cputimer dummy_cputimer = { 54 SLIST_ENTRY_INITIALIZER, 55 "dummy", 56 CPUTIMER_PRI_DUMMY, 57 CPUTIMER_DUMMY, 58 dummy_cputimer_count, 59 cputimer_default_fromhz, 60 cputimer_default_fromus, 61 cputimer_default_construct, 62 cputimer_default_destruct, 63 1000000, 64 (1000000LL << 32) / 1000000, 65 (1000000000LL << 32) / 1000000, 66 0 67 }; 68 69 struct cputimer *sys_cputimer = &dummy_cputimer; 70 SLIST_HEAD(, cputimer) cputimerhead = SLIST_HEAD_INITIALIZER(&cputimerhead); 71 72 static int cputimer_intr_ps_reqs; 73 static struct lwkt_serialize cputimer_intr_ps_slize = 74 LWKT_SERIALIZE_INITIALIZER; 75 76 /* 77 * Generic cputimer API 78 */ 79 void 80 cputimer_select(struct cputimer *timer, int pri) 81 { 82 sysclock_t oldclock; 83 84 /* 85 * Calculate helper fields 86 */ 87 cputimer_set_frequency(timer, timer->freq); 88 89 /* 90 * Install a new cputimer if its priority allows it. If timer is 91 * passed as NULL we deinstall the current timer and revert to our 92 * dummy. 93 */ 94 if (pri == 0) 95 pri = timer->pri; 96 if (timer == NULL || pri >= sys_cputimer->pri) { 97 oldclock = sys_cputimer->count(); 98 sys_cputimer->destruct(sys_cputimer); 99 sys_cputimer = &dummy_cputimer; 100 if (timer) { 101 sys_cputimer = timer; 102 timer->construct(timer, oldclock); 103 cputimer_intr_config(timer); 104 } 105 } 106 } 107 108 /* 109 * Register a timer. If the timer has already been registered, do nothing. 110 */ 111 void 112 cputimer_register(struct cputimer *timer) 113 { 114 struct cputimer *scan; 115 116 /* 117 * Initialize dummy_cputimer if the slist is empty, it does not get 118 * registered the normal way. 119 */ 120 if (SLIST_EMPTY(&cputimerhead)) 121 SLIST_FIRST(&cputimerhead) = &dummy_cputimer; 122 SLIST_FOREACH(scan, &cputimerhead, next) { 123 if (scan == timer) 124 return; 125 } 126 SLIST_INSERT_HEAD(&cputimerhead, timer, next); 127 } 128 129 /* 130 * Deregister a timer. If the timer has already been deregistered, do nothing. 131 */ 132 void 133 cputimer_deregister(struct cputimer *timer) 134 { 135 struct cputimer *scan; 136 struct cputimer *best; 137 138 /* 139 * Locate and remove the timer. If the timer is our currently active 140 * timer, revert to the dummy timer. 141 */ 142 SLIST_FOREACH(scan, &cputimerhead, next) { 143 if (timer == scan) { 144 if (timer == sys_cputimer) 145 cputimer_select(&dummy_cputimer, 0x7FFFFFFF); 146 SLIST_REMOVE(&cputimerhead, timer, cputimer, next); 147 break; 148 } 149 } 150 151 /* 152 * If sys_cputimer reverted to the dummy, select the best one 153 */ 154 if (sys_cputimer == &dummy_cputimer) { 155 best = NULL; 156 SLIST_FOREACH(scan, &cputimerhead, next) { 157 if (best == NULL || scan->pri > best->pri) 158 best = scan; 159 } 160 if (best) 161 cputimer_select(best, 0x7FFFFFFF); 162 } 163 } 164 165 /* 166 * Calculate usec / tick and nsec / tick, scaled by (1 << 32). 167 * 168 * so e.g. a 3 mhz timer would be 3 usec / tick x (1 << 32), 169 * or 3000 nsec / tick x (1 << 32) 170 */ 171 void 172 cputimer_set_frequency(struct cputimer *timer, sysclock_t freq) 173 { 174 timer->freq = freq; 175 timer->freq64_usec = (1000000LL << 32) / freq; 176 timer->freq64_nsec = (1000000000LL << 32) / freq; 177 if (timer == sys_cputimer) 178 cputimer_intr_config(timer); 179 } 180 181 sysclock_t 182 cputimer_default_fromhz(int freq) 183 { 184 return(sys_cputimer->freq / freq + 1); 185 } 186 187 sysclock_t 188 cputimer_default_fromus(int us) 189 { 190 return((int64_t)sys_cputimer->freq * us / 1000000); 191 } 192 193 /* 194 * Dummy counter implementation 195 */ 196 static 197 sysclock_t 198 dummy_cputimer_count(void) 199 { 200 return(++dummy_cputimer.base); 201 } 202 203 void 204 cputimer_default_construct(struct cputimer *cputimer, sysclock_t oldclock) 205 { 206 cputimer->base = oldclock; 207 } 208 209 void 210 cputimer_default_destruct(struct cputimer *cputimer) 211 { 212 } 213 214 /************************************************************************ 215 * SYSCTL SUPPORT * 216 ************************************************************************ 217 * 218 * Note: the ability to change the systimer is not currently enabled 219 * because it will mess up systimer calculations. You have to live 220 * with what is configured at boot. 221 */ 222 static int 223 sysctl_cputimer_reglist(SYSCTL_HANDLER_ARGS) 224 { 225 struct cputimer *scan; 226 int error = 0; 227 int loop = 0; 228 229 /* 230 * Build a list of available timers 231 */ 232 SLIST_FOREACH(scan, &cputimerhead, next) { 233 if (error == 0 && loop) 234 error = SYSCTL_OUT(req, " ", 1); 235 if (error == 0) 236 error = SYSCTL_OUT(req, scan->name, strlen(scan->name)); 237 ++loop; 238 } 239 return (error); 240 } 241 242 static int 243 sysctl_cputimer_name(SYSCTL_HANDLER_ARGS) 244 { 245 int error; 246 247 error = SYSCTL_OUT(req, sys_cputimer->name, strlen(sys_cputimer->name)); 248 return (error); 249 } 250 251 static int 252 sysctl_cputimer_clock(SYSCTL_HANDLER_ARGS) 253 { 254 sysclock_t clock; 255 int error; 256 257 clock = sys_cputimer->count(); 258 error = SYSCTL_OUT(req, &clock, sizeof(clock)); 259 return (error); 260 } 261 262 static int 263 sysctl_cputimer_freq(SYSCTL_HANDLER_ARGS) 264 { 265 int error; 266 267 error = SYSCTL_OUT(req, &sys_cputimer->freq, sizeof(sys_cputimer->freq)); 268 return (error); 269 } 270 271 SYSCTL_DECL(_kern_cputimer); 272 SYSCTL_NODE(_kern, OID_AUTO, cputimer, CTLFLAG_RW, NULL, "cputimer"); 273 274 SYSCTL_PROC(_kern_cputimer, OID_AUTO, select, CTLTYPE_STRING|CTLFLAG_RD, 275 NULL, 0, sysctl_cputimer_reglist, "A", ""); 276 SYSCTL_PROC(_kern_cputimer, OID_AUTO, name, CTLTYPE_STRING|CTLFLAG_RD, 277 NULL, 0, sysctl_cputimer_name, "A", ""); 278 SYSCTL_PROC(_kern_cputimer, OID_AUTO, clock, CTLTYPE_UINT|CTLFLAG_RD, 279 NULL, 0, sysctl_cputimer_clock, "IU", ""); 280 SYSCTL_PROC(_kern_cputimer, OID_AUTO, freq, CTLTYPE_INT|CTLFLAG_RD, 281 NULL, 0, sysctl_cputimer_freq, "I", ""); 282 283 static struct cputimer_intr *sys_cputimer_intr; 284 static uint32_t cputimer_intr_caps; 285 SLIST_HEAD(, cputimer_intr) cputimer_intr_head = 286 SLIST_HEAD_INITIALIZER(&cputimer_intr_head); 287 288 void 289 cputimer_intr_register(struct cputimer_intr *cti) 290 { 291 struct cputimer_intr *scan; 292 293 SLIST_FOREACH(scan, &cputimer_intr_head, next) { 294 if (scan == cti) 295 return; 296 } 297 cti->config(cti, sys_cputimer); 298 SLIST_INSERT_HEAD(&cputimer_intr_head, cti, next); 299 } 300 301 void 302 cputimer_intr_deregister(struct cputimer_intr *cti) 303 { 304 KKASSERT(cti != sys_cputimer_intr); 305 SLIST_REMOVE(&cputimer_intr_head, cti, cputimer_intr, next); 306 } 307 308 int 309 cputimer_intr_select(struct cputimer_intr *cti, int prio) 310 { 311 KKASSERT(cti != NULL); 312 313 if (prio == 0) 314 prio = cti->prio; 315 316 if (sys_cputimer_intr == NULL) { 317 KKASSERT(cputimer_intr_caps == 0); 318 sys_cputimer_intr = cti; 319 return 0; 320 } 321 322 if ((cti->caps & cputimer_intr_caps) == cputimer_intr_caps) { 323 if (prio > sys_cputimer_intr->prio) { 324 sys_cputimer_intr = cti; 325 return 0; 326 } else { 327 return EBUSY; 328 } 329 } else { 330 return EOPNOTSUPP; 331 } 332 } 333 334 void 335 cputimer_intr_default_enable(struct cputimer_intr *cti __unused) 336 { 337 } 338 339 void 340 cputimer_intr_default_restart(struct cputimer_intr *cti) 341 { 342 cti->reload(cti, 0); 343 } 344 345 void 346 cputimer_intr_default_config(struct cputimer_intr *cti __unused, 347 const struct cputimer *timer __unused) 348 { 349 } 350 351 void 352 cputimer_intr_default_pmfixup(struct cputimer_intr *cti __unused) 353 { 354 } 355 356 void 357 cputimer_intr_default_initclock(struct cputimer_intr *cti __unused, 358 boolean_t selected __unused) 359 { 360 } 361 362 void 363 cputimer_intr_enable(void) 364 { 365 struct cputimer_intr *cti; 366 367 SLIST_FOREACH(cti, &cputimer_intr_head, next) 368 cti->enable(cti); 369 } 370 371 void 372 cputimer_intr_config(const struct cputimer *timer) 373 { 374 struct cputimer_intr *cti; 375 376 SLIST_FOREACH(cti, &cputimer_intr_head, next) 377 cti->config(cti, timer); 378 } 379 380 void 381 cputimer_intr_pmfixup(void) 382 { 383 struct cputimer_intr *cti; 384 385 SLIST_FOREACH(cti, &cputimer_intr_head, next) 386 cti->pmfixup(cti); 387 } 388 389 void 390 cputimer_intr_reload(sysclock_t reload) 391 { 392 struct cputimer_intr *cti = sys_cputimer_intr; 393 394 cti->reload(cti, reload); 395 } 396 397 void 398 cputimer_intr_restart(void) 399 { 400 struct cputimer_intr *cti = sys_cputimer_intr; 401 402 cti->restart(cti); 403 } 404 405 int 406 cputimer_intr_select_caps(uint32_t caps) 407 { 408 struct cputimer_intr *cti, *maybe; 409 int error; 410 411 maybe = NULL; 412 SLIST_FOREACH(cti, &cputimer_intr_head, next) { 413 if ((cti->caps & caps) == caps) { 414 if (maybe == NULL) 415 maybe = cti; 416 else if (cti->prio > maybe->prio) 417 maybe = cti; 418 } 419 } 420 if (maybe == NULL) 421 return ENOENT; 422 423 if (sys_cputimer_intr == maybe) 424 return 0; 425 426 cputimer_intr_caps = caps; 427 error = cputimer_intr_select(maybe, CPUTIMER_INTR_PRIO_MAX); 428 KKASSERT(!error); 429 430 return ERESTART; 431 } 432 433 static void 434 cputimer_intr_initclocks(void) 435 { 436 struct cputimer_intr *cti, *ncti; 437 438 /* 439 * An interrupt cputimer may deregister itself, 440 * so use SLIST_FOREACH_MUTABLE here. 441 */ 442 SLIST_FOREACH_MUTABLE(cti, &cputimer_intr_head, next, ncti) { 443 boolean_t selected = FALSE; 444 445 if (cti == sys_cputimer_intr) 446 selected = TRUE; 447 cti->initclock(cti, selected); 448 } 449 } 450 /* NOTE: Must be SECOND to allow platform initialization to go first */ 451 SYSINIT(cputimer_intr, SI_BOOT2_CLOCKREG, SI_ORDER_SECOND, 452 cputimer_intr_initclocks, NULL); 453 454 static int 455 sysctl_cputimer_intr_reglist(SYSCTL_HANDLER_ARGS) 456 { 457 struct cputimer_intr *scan; 458 int error = 0; 459 int loop = 0; 460 461 /* 462 * Build a list of available interrupt cputimers 463 */ 464 SLIST_FOREACH(scan, &cputimer_intr_head, next) { 465 if (error == 0 && loop) 466 error = SYSCTL_OUT(req, " ", 1); 467 if (error == 0) 468 error = SYSCTL_OUT(req, scan->name, strlen(scan->name)); 469 ++loop; 470 } 471 return (error); 472 } 473 474 static int 475 sysctl_cputimer_intr_freq(SYSCTL_HANDLER_ARGS) 476 { 477 int error; 478 479 error = SYSCTL_OUT(req, &sys_cputimer_intr->freq, 480 sizeof(sys_cputimer_intr->freq)); 481 return (error); 482 } 483 484 static int 485 sysctl_cputimer_intr_select(SYSCTL_HANDLER_ARGS) 486 { 487 struct cputimer_intr *cti; 488 char name[32]; 489 int error; 490 491 ksnprintf(name, sizeof(name), "%s", sys_cputimer_intr->name); 492 error = sysctl_handle_string(oidp, name, sizeof(name), req); 493 if (error != 0 || req->newptr == NULL) 494 return error; 495 496 SLIST_FOREACH(cti, &cputimer_intr_head, next) { 497 if (strcmp(cti->name, name) == 0) 498 break; 499 } 500 if (cti == NULL) 501 return ENOENT; 502 if (cti == sys_cputimer_intr) 503 return 0; 504 505 error = cputimer_intr_select(cti, CPUTIMER_INTR_PRIO_MAX); 506 if (!error) 507 cputimer_intr_restart(); 508 return error; 509 } 510 511 SYSCTL_NODE(_kern_cputimer, OID_AUTO, intr, CTLFLAG_RW, NULL, 512 "interrupt cputimer"); 513 514 SYSCTL_PROC(_kern_cputimer_intr, OID_AUTO, reglist, CTLTYPE_STRING|CTLFLAG_RD, 515 NULL, 0, sysctl_cputimer_intr_reglist, "A", ""); 516 SYSCTL_PROC(_kern_cputimer_intr, OID_AUTO, freq, CTLTYPE_INT|CTLFLAG_RD, 517 NULL, 0, sysctl_cputimer_intr_freq, "I", ""); 518 SYSCTL_PROC(_kern_cputimer_intr, OID_AUTO, select, CTLTYPE_STRING|CTLFLAG_RW, 519 NULL, 0, sysctl_cputimer_intr_select, "A", ""); 520 521 int 522 cputimer_intr_powersave_addreq(void) 523 { 524 int error = 0; 525 526 lwkt_serialize_enter(&cputimer_intr_ps_slize); 527 528 ++cputimer_intr_ps_reqs; 529 if (cputimer_intr_ps_reqs == 1) { 530 /* 531 * Upon the first power saving request, switch to an one shot 532 * timer, which would not stop in the any power saving state. 533 */ 534 error = cputimer_intr_select_caps(CPUTIMER_INTR_CAP_PS); 535 if (error == ERESTART) { 536 error = 0; 537 if (bootverbose) 538 kprintf("cputimer: first power save request, restart\n"); 539 cputimer_intr_restart(); 540 } else if (error) { 541 kprintf("no suitable intr cputimer found\n"); 542 --cputimer_intr_ps_reqs; 543 } else if (bootverbose) { 544 kprintf("cputimer: first power save request\n"); 545 } 546 } 547 548 lwkt_serialize_exit(&cputimer_intr_ps_slize); 549 550 return error; 551 } 552 553 void 554 cputimer_intr_powersave_remreq(void) 555 { 556 lwkt_serialize_enter(&cputimer_intr_ps_slize); 557 558 KASSERT(cputimer_intr_ps_reqs > 0, 559 ("invalid # of powersave reqs %d", cputimer_intr_ps_reqs)); 560 --cputimer_intr_ps_reqs; 561 if (cputimer_intr_ps_reqs == 0) { 562 int error; 563 564 /* No one needs power saving, use a better one shot timer. */ 565 error = cputimer_intr_select_caps(CPUTIMER_INTR_CAP_NONE); 566 KKASSERT(!error || error == ERESTART); 567 if (error == ERESTART) { 568 if (bootverbose) 569 kprintf("cputimer: no powser save request, restart\n"); 570 cputimer_intr_restart(); 571 } else if (bootverbose) { 572 kprintf("cputimer: no power save request\n"); 573 } 574 } 575 576 lwkt_serialize_exit(&cputimer_intr_ps_slize); 577 } 578 579 static __inline void 580 cputimer_intr_pcpuhand(void) 581 { 582 struct cputimer_intr *cti = sys_cputimer_intr; 583 584 if (cti->pcpuhand != NULL) 585 cti->pcpuhand(cti); 586 } 587 588 static void 589 pcpu_timer_process_oncpu(struct globaldata *gd, struct intrframe *frame) 590 { 591 sysclock_t count; 592 593 cputimer_intr_pcpuhand(); 594 595 gd->gd_timer_running = 0; 596 597 count = sys_cputimer->count(); 598 if (TAILQ_FIRST(&gd->gd_systimerq) != NULL) 599 systimer_intr(&count, 0, frame); 600 } 601 602 void 603 pcpu_timer_process(void) 604 { 605 pcpu_timer_process_oncpu(mycpu, NULL); 606 } 607 608 void 609 pcpu_timer_process_frame(struct intrframe *frame) 610 { 611 pcpu_timer_process_oncpu(mycpu, frame); 612 } 613