1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright 2009 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 /* 26 * Copyright (c) 2009, Intel Corporation. 27 * All Rights Reserved. 28 */ 29 30 /* 31 * CPU Device driver. The driver is not DDI-compliant. 32 * 33 * The driver supports following features: 34 * - Power management. 35 */ 36 37 #include <sys/types.h> 38 #include <sys/param.h> 39 #include <sys/errno.h> 40 #include <sys/modctl.h> 41 #include <sys/kmem.h> 42 #include <sys/conf.h> 43 #include <sys/cmn_err.h> 44 #include <sys/stat.h> 45 #include <sys/debug.h> 46 #include <sys/systm.h> 47 #include <sys/ddi.h> 48 #include <sys/sunddi.h> 49 #include <sys/sdt.h> 50 #include <sys/epm.h> 51 #include <sys/machsystm.h> 52 #include <sys/x_call.h> 53 #include <sys/cpudrv_mach.h> 54 #include <sys/msacct.h> 55 56 /* 57 * CPU power management 58 * 59 * The supported power saving model is to slow down the CPU (on SPARC by 60 * dividing the CPU clock and on x86 by dropping down a P-state). 61 * Periodically we determine the amount of time the CPU is running 62 * idle thread and threads in user mode during the last quantum. If the idle 63 * thread was running less than its low water mark for current speed for 64 * number of consecutive sampling periods, or number of running threads in 65 * user mode are above its high water mark, we arrange to go to the higher 66 * speed. If the idle thread was running more than its high water mark without 67 * dropping a number of consecutive times below the mark, and number of threads 68 * running in user mode are below its low water mark, we arrange to go to the 69 * next lower speed. While going down, we go through all the speeds. While 70 * going up we go to the maximum speed to minimize impact on the user, but have 71 * provisions in the driver to go to other speeds. 72 * 73 * The driver does not have knowledge of a particular implementation of this 74 * scheme and will work with all CPUs supporting this model. On SPARC, the 75 * driver determines supported speeds by looking at 'clock-divisors' property 76 * created by OBP. On x86, the driver retrieves the supported speeds from 77 * ACPI. 78 */ 79 80 /* 81 * Configuration function prototypes and data structures 82 */ 83 static int cpudrv_attach(dev_info_t *dip, ddi_attach_cmd_t cmd); 84 static int cpudrv_detach(dev_info_t *dip, ddi_detach_cmd_t cmd); 85 static int cpudrv_power(dev_info_t *dip, int comp, int level); 86 87 struct dev_ops cpudrv_ops = { 88 DEVO_REV, /* rev */ 89 0, /* refcnt */ 90 nodev, /* getinfo */ 91 nulldev, /* identify */ 92 nulldev, /* probe */ 93 cpudrv_attach, /* attach */ 94 cpudrv_detach, /* detach */ 95 nodev, /* reset */ 96 (struct cb_ops *)NULL, /* cb_ops */ 97 (struct bus_ops *)NULL, /* bus_ops */ 98 cpudrv_power, /* power */ 99 ddi_quiesce_not_needed, /* quiesce */ 100 }; 101 102 static struct modldrv modldrv = { 103 &mod_driverops, /* modops */ 104 "CPU Driver", /* linkinfo */ 105 &cpudrv_ops, /* dev_ops */ 106 }; 107 108 static struct modlinkage modlinkage = { 109 MODREV_1, /* rev */ 110 &modldrv, /* linkage */ 111 NULL 112 }; 113 114 /* 115 * Function prototypes 116 */ 117 static int cpudrv_init(cpudrv_devstate_t *cpudsp); 118 static void cpudrv_free(cpudrv_devstate_t *cpudsp); 119 static int cpudrv_comp_create(cpudrv_devstate_t *cpudsp); 120 static void cpudrv_monitor_disp(void *arg); 121 static void cpudrv_monitor(void *arg); 122 123 /* 124 * Driver global variables 125 */ 126 uint_t cpudrv_debug = 0; 127 void *cpudrv_state; 128 static uint_t cpudrv_idle_hwm = CPUDRV_IDLE_HWM; 129 static uint_t cpudrv_idle_lwm = CPUDRV_IDLE_LWM; 130 static uint_t cpudrv_idle_buf_zone = CPUDRV_IDLE_BUF_ZONE; 131 static uint_t cpudrv_idle_bhwm_cnt_max = CPUDRV_IDLE_BHWM_CNT_MAX; 132 static uint_t cpudrv_idle_blwm_cnt_max = CPUDRV_IDLE_BLWM_CNT_MAX; 133 static uint_t cpudrv_user_hwm = CPUDRV_USER_HWM; 134 135 boolean_t cpudrv_enabled = B_TRUE; 136 137 /* 138 * cpudrv_direct_pm allows user applications to directly control the 139 * power state transitions (direct pm) without following the normal 140 * direct pm protocol. This is needed because the normal protocol 141 * requires that a device only be lowered when it is idle, and be 142 * brought up when it request to do so by calling pm_raise_power(). 143 * Ignoring this protocol is harmless for CPU (other than speed). 144 * Moreover it might be the case that CPU is never idle or wants 145 * to be at higher speed because of the addition CPU cycles required 146 * to run the user application. 147 * 148 * The driver will still report idle/busy status to the framework. Although 149 * framework will ignore this information for direct pm devices and not 150 * try to bring them down when idle, user applications can still use this 151 * information if they wants. 152 * 153 * In the future, provide an ioctl to control setting of this mode. In 154 * that case, this variable should move to the state structure and 155 * be protected by the lock in the state structure. 156 */ 157 int cpudrv_direct_pm = 0; 158 159 /* 160 * Arranges for the handler function to be called at the interval suitable 161 * for current speed. 162 */ 163 #define CPUDRV_MONITOR_INIT(cpudsp) { \ 164 if (cpudrv_is_enabled(cpudsp)) { \ 165 ASSERT(mutex_owned(&(cpudsp)->lock)); \ 166 (cpudsp)->cpudrv_pm.timeout_id = \ 167 timeout(cpudrv_monitor_disp, \ 168 (cpudsp), (((cpudsp)->cpudrv_pm.cur_spd == NULL) ? \ 169 CPUDRV_QUANT_CNT_OTHR : \ 170 (cpudsp)->cpudrv_pm.cur_spd->quant_cnt)); \ 171 } \ 172 } 173 174 /* 175 * Arranges for the handler function not to be called back. 176 */ 177 #define CPUDRV_MONITOR_FINI(cpudsp) { \ 178 timeout_id_t tmp_tid; \ 179 ASSERT(mutex_owned(&(cpudsp)->lock)); \ 180 tmp_tid = (cpudsp)->cpudrv_pm.timeout_id; \ 181 (cpudsp)->cpudrv_pm.timeout_id = 0; \ 182 mutex_exit(&(cpudsp)->lock); \ 183 if (tmp_tid != 0) { \ 184 (void) untimeout(tmp_tid); \ 185 mutex_enter(&(cpudsp)->cpudrv_pm.timeout_lock); \ 186 while ((cpudsp)->cpudrv_pm.timeout_count != 0) \ 187 cv_wait(&(cpudsp)->cpudrv_pm.timeout_cv, \ 188 &(cpudsp)->cpudrv_pm.timeout_lock); \ 189 mutex_exit(&(cpudsp)->cpudrv_pm.timeout_lock); \ 190 } \ 191 mutex_enter(&(cpudsp)->lock); \ 192 } 193 194 int 195 _init(void) 196 { 197 int error; 198 199 DPRINTF(D_INIT, (" _init: function called\n")); 200 if ((error = ddi_soft_state_init(&cpudrv_state, 201 sizeof (cpudrv_devstate_t), 0)) != 0) { 202 return (error); 203 } 204 205 if ((error = mod_install(&modlinkage)) != 0) { 206 ddi_soft_state_fini(&cpudrv_state); 207 } 208 209 /* 210 * Callbacks used by the PPM driver. 211 */ 212 CPUDRV_SET_PPM_CALLBACKS(); 213 return (error); 214 } 215 216 int 217 _fini(void) 218 { 219 int error; 220 221 DPRINTF(D_FINI, (" _fini: function called\n")); 222 if ((error = mod_remove(&modlinkage)) == 0) { 223 ddi_soft_state_fini(&cpudrv_state); 224 } 225 226 return (error); 227 } 228 229 int 230 _info(struct modinfo *modinfop) 231 { 232 return (mod_info(&modlinkage, modinfop)); 233 } 234 235 /* 236 * Driver attach(9e) entry point. 237 */ 238 static int 239 cpudrv_attach(dev_info_t *dip, ddi_attach_cmd_t cmd) 240 { 241 int instance; 242 cpudrv_devstate_t *cpudsp; 243 244 instance = ddi_get_instance(dip); 245 246 switch (cmd) { 247 case DDI_ATTACH: 248 DPRINTF(D_ATTACH, ("cpudrv_attach: instance %d: " 249 "DDI_ATTACH called\n", instance)); 250 if (!cpudrv_is_enabled(NULL)) 251 return (DDI_FAILURE); 252 if (ddi_soft_state_zalloc(cpudrv_state, instance) != 253 DDI_SUCCESS) { 254 cmn_err(CE_WARN, "cpudrv_attach: instance %d: " 255 "can't allocate state", instance); 256 cpudrv_enabled = B_FALSE; 257 return (DDI_FAILURE); 258 } 259 if ((cpudsp = ddi_get_soft_state(cpudrv_state, instance)) == 260 NULL) { 261 cmn_err(CE_WARN, "cpudrv_attach: instance %d: " 262 "can't get state", instance); 263 ddi_soft_state_free(cpudrv_state, instance); 264 cpudrv_enabled = B_FALSE; 265 return (DDI_FAILURE); 266 } 267 cpudsp->dip = dip; 268 269 /* 270 * Find CPU number for this dev_info node. 271 */ 272 if (!cpudrv_get_cpu_id(dip, &(cpudsp->cpu_id))) { 273 cmn_err(CE_WARN, "cpudrv_attach: instance %d: " 274 "can't convert dip to cpu_id", instance); 275 ddi_soft_state_free(cpudrv_state, instance); 276 cpudrv_enabled = B_FALSE; 277 return (DDI_FAILURE); 278 } 279 280 mutex_init(&cpudsp->lock, NULL, MUTEX_DRIVER, NULL); 281 if (cpudrv_is_enabled(cpudsp)) { 282 if (cpudrv_init(cpudsp) != DDI_SUCCESS) { 283 cpudrv_enabled = B_FALSE; 284 cpudrv_free(cpudsp); 285 ddi_soft_state_free(cpudrv_state, instance); 286 return (DDI_FAILURE); 287 } 288 if (cpudrv_comp_create(cpudsp) != DDI_SUCCESS) { 289 cpudrv_enabled = B_FALSE; 290 cpudrv_free(cpudsp); 291 ddi_soft_state_free(cpudrv_state, instance); 292 return (DDI_FAILURE); 293 } 294 if (ddi_prop_update_string(DDI_DEV_T_NONE, 295 dip, "pm-class", "CPU") != DDI_PROP_SUCCESS) { 296 cpudrv_enabled = B_FALSE; 297 cpudrv_free(cpudsp); 298 ddi_soft_state_free(cpudrv_state, instance); 299 return (DDI_FAILURE); 300 } 301 302 /* 303 * Taskq is used to dispatch routine to monitor CPU 304 * activities. 305 */ 306 cpudsp->cpudrv_pm.tq = ddi_taskq_create(dip, 307 "cpudrv_monitor", CPUDRV_TASKQ_THREADS, 308 TASKQ_DEFAULTPRI, 0); 309 310 mutex_init(&cpudsp->cpudrv_pm.timeout_lock, NULL, 311 MUTEX_DRIVER, NULL); 312 cv_init(&cpudsp->cpudrv_pm.timeout_cv, NULL, 313 CV_DEFAULT, NULL); 314 315 /* 316 * Driver needs to assume that CPU is running at 317 * unknown speed at DDI_ATTACH and switch it to the 318 * needed speed. We assume that initial needed speed 319 * is full speed for us. 320 */ 321 /* 322 * We need to take the lock because cpudrv_monitor() 323 * will start running in parallel with attach(). 324 */ 325 mutex_enter(&cpudsp->lock); 326 cpudsp->cpudrv_pm.cur_spd = NULL; 327 cpudsp->cpudrv_pm.pm_started = B_FALSE; 328 /* 329 * We don't call pm_raise_power() directly from attach 330 * because driver attach for a slave CPU node can 331 * happen before the CPU is even initialized. We just 332 * start the monitoring system which understands 333 * unknown speed and moves CPU to top speed when it 334 * has been initialized. 335 */ 336 CPUDRV_MONITOR_INIT(cpudsp); 337 mutex_exit(&cpudsp->lock); 338 339 } 340 341 if (!cpudrv_mach_init(cpudsp)) { 342 cmn_err(CE_WARN, "cpudrv_attach: instance %d: " 343 "cpudrv_mach_init failed", instance); 344 cpudrv_enabled = B_FALSE; 345 cpudrv_free(cpudsp); 346 ddi_soft_state_free(cpudrv_state, instance); 347 return (DDI_FAILURE); 348 } 349 350 CPUDRV_INSTALL_MAX_CHANGE_HANDLER(cpudsp); 351 352 (void) ddi_prop_update_int(DDI_DEV_T_NONE, dip, 353 DDI_NO_AUTODETACH, 1); 354 ddi_report_dev(dip); 355 return (DDI_SUCCESS); 356 357 case DDI_RESUME: 358 DPRINTF(D_ATTACH, ("cpudrv_attach: instance %d: " 359 "DDI_RESUME called\n", instance)); 360 361 cpudsp = ddi_get_soft_state(cpudrv_state, instance); 362 ASSERT(cpudsp != NULL); 363 364 /* 365 * Nothing to do for resume, if not doing active PM. 366 */ 367 if (!cpudrv_is_enabled(cpudsp)) 368 return (DDI_SUCCESS); 369 370 mutex_enter(&cpudsp->lock); 371 /* 372 * Driver needs to assume that CPU is running at unknown speed 373 * at DDI_RESUME and switch it to the needed speed. We assume 374 * that the needed speed is full speed for us. 375 */ 376 cpudsp->cpudrv_pm.cur_spd = NULL; 377 CPUDRV_MONITOR_INIT(cpudsp); 378 mutex_exit(&cpudsp->lock); 379 CPUDRV_REDEFINE_TOPSPEED(dip); 380 return (DDI_SUCCESS); 381 382 default: 383 return (DDI_FAILURE); 384 } 385 } 386 387 /* 388 * Driver detach(9e) entry point. 389 */ 390 static int 391 cpudrv_detach(dev_info_t *dip, ddi_detach_cmd_t cmd) 392 { 393 int instance; 394 cpudrv_devstate_t *cpudsp; 395 cpudrv_pm_t *cpupm; 396 397 instance = ddi_get_instance(dip); 398 399 switch (cmd) { 400 case DDI_DETACH: 401 DPRINTF(D_DETACH, ("cpudrv_detach: instance %d: " 402 "DDI_DETACH called\n", instance)); 403 404 #if defined(__x86) 405 cpudsp = ddi_get_soft_state(cpudrv_state, instance); 406 ASSERT(cpudsp != NULL); 407 408 /* 409 * Nothing to do for detach, if no doing active PM. 410 */ 411 if (!cpudrv_is_enabled(cpudsp)) 412 return (DDI_SUCCESS); 413 414 /* 415 * uninstall PPC/_TPC change notification handler 416 */ 417 CPUDRV_UNINSTALL_MAX_CHANGE_HANDLER(cpudsp); 418 419 /* 420 * destruct platform specific resource 421 */ 422 if (!cpudrv_mach_fini(cpudsp)) 423 return (DDI_FAILURE); 424 425 mutex_enter(&cpudsp->lock); 426 CPUDRV_MONITOR_FINI(cpudsp); 427 cv_destroy(&cpudsp->cpudrv_pm.timeout_cv); 428 mutex_destroy(&cpudsp->cpudrv_pm.timeout_lock); 429 ddi_taskq_destroy(cpudsp->cpudrv_pm.tq); 430 cpudrv_free(cpudsp); 431 mutex_exit(&cpudsp->lock); 432 mutex_destroy(&cpudsp->lock); 433 ddi_soft_state_free(cpudrv_state, instance); 434 (void) ddi_prop_update_int(DDI_DEV_T_NONE, dip, 435 DDI_NO_AUTODETACH, 0); 436 return (DDI_SUCCESS); 437 438 #else 439 /* 440 * If the only thing supported by the driver is power 441 * management, we can in future enhance the driver and 442 * framework that loads it to unload the driver when 443 * user has disabled CPU power management. 444 */ 445 return (DDI_FAILURE); 446 #endif 447 448 case DDI_SUSPEND: 449 DPRINTF(D_DETACH, ("cpudrv_detach: instance %d: " 450 "DDI_SUSPEND called\n", instance)); 451 452 cpudsp = ddi_get_soft_state(cpudrv_state, instance); 453 ASSERT(cpudsp != NULL); 454 455 /* 456 * Nothing to do for suspend, if not doing active PM. 457 */ 458 if (!cpudrv_is_enabled(cpudsp)) 459 return (DDI_SUCCESS); 460 461 /* 462 * During a checkpoint-resume sequence, framework will 463 * stop interrupts to quiesce kernel activity. This will 464 * leave our monitoring system ineffective. Handle this 465 * by stopping our monitoring system and bringing CPU 466 * to full speed. In case we are in special direct pm 467 * mode, we leave the CPU at whatever speed it is. This 468 * is harmless other than speed. 469 */ 470 mutex_enter(&cpudsp->lock); 471 cpupm = &(cpudsp->cpudrv_pm); 472 473 DPRINTF(D_DETACH, ("cpudrv_detach: instance %d: DDI_SUSPEND - " 474 "cur_spd %d, topspeed %d\n", instance, 475 cpupm->cur_spd->pm_level, 476 CPUDRV_TOPSPEED(cpupm)->pm_level)); 477 478 CPUDRV_MONITOR_FINI(cpudsp); 479 480 if (!cpudrv_direct_pm && (cpupm->cur_spd != 481 CPUDRV_TOPSPEED(cpupm))) { 482 if (cpupm->pm_busycnt < 1) { 483 if ((pm_busy_component(dip, CPUDRV_COMP_NUM) 484 == DDI_SUCCESS)) { 485 cpupm->pm_busycnt++; 486 } else { 487 CPUDRV_MONITOR_INIT(cpudsp); 488 mutex_exit(&cpudsp->lock); 489 cmn_err(CE_WARN, "cpudrv_detach: " 490 "instance %d: can't busy CPU " 491 "component", instance); 492 return (DDI_FAILURE); 493 } 494 } 495 mutex_exit(&cpudsp->lock); 496 if (pm_raise_power(dip, CPUDRV_COMP_NUM, 497 CPUDRV_TOPSPEED(cpupm)->pm_level) != 498 DDI_SUCCESS) { 499 mutex_enter(&cpudsp->lock); 500 CPUDRV_MONITOR_INIT(cpudsp); 501 mutex_exit(&cpudsp->lock); 502 cmn_err(CE_WARN, "cpudrv_detach: instance %d: " 503 "can't raise CPU power level to %d", 504 instance, 505 CPUDRV_TOPSPEED(cpupm)->pm_level); 506 return (DDI_FAILURE); 507 } else { 508 return (DDI_SUCCESS); 509 } 510 } else { 511 mutex_exit(&cpudsp->lock); 512 return (DDI_SUCCESS); 513 } 514 515 default: 516 return (DDI_FAILURE); 517 } 518 } 519 520 /* 521 * Driver power(9e) entry point. 522 * 523 * Driver's notion of current power is set *only* in power(9e) entry point 524 * after actual power change operation has been successfully completed. 525 */ 526 /* ARGSUSED */ 527 static int 528 cpudrv_power(dev_info_t *dip, int comp, int level) 529 { 530 int instance; 531 cpudrv_devstate_t *cpudsp; 532 cpudrv_pm_t *cpudrvpm; 533 cpudrv_pm_spd_t *new_spd; 534 boolean_t is_ready; 535 int ret; 536 537 instance = ddi_get_instance(dip); 538 539 DPRINTF(D_POWER, ("cpudrv_power: instance %d: level %d\n", 540 instance, level)); 541 542 if ((cpudsp = ddi_get_soft_state(cpudrv_state, instance)) == NULL) { 543 cmn_err(CE_WARN, "cpudrv_power: instance %d: can't " 544 "get state", instance); 545 return (DDI_FAILURE); 546 } 547 548 /* 549 * We're not ready until we can get a cpu_t 550 */ 551 is_ready = (cpudrv_get_cpu(cpudsp) == DDI_SUCCESS); 552 553 mutex_enter(&cpudsp->lock); 554 cpudrvpm = &(cpudsp->cpudrv_pm); 555 556 /* 557 * In normal operation, we fail if we are busy and request is 558 * to lower the power level. We let this go through if the driver 559 * is in special direct pm mode. On x86, we also let this through 560 * if the change is due to a request to govern the max speed. 561 */ 562 if (!cpudrv_direct_pm && (cpudrvpm->pm_busycnt >= 1) && 563 !cpudrv_is_governor_thread(cpudrvpm)) { 564 if ((cpudrvpm->cur_spd != NULL) && 565 (level < cpudrvpm->cur_spd->pm_level)) { 566 mutex_exit(&cpudsp->lock); 567 return (DDI_FAILURE); 568 } 569 } 570 571 for (new_spd = cpudrvpm->head_spd; new_spd; new_spd = 572 new_spd->down_spd) { 573 if (new_spd->pm_level == level) 574 break; 575 } 576 if (!new_spd) { 577 CPUDRV_RESET_GOVERNOR_THREAD(cpudrvpm); 578 mutex_exit(&cpudsp->lock); 579 cmn_err(CE_WARN, "cpudrv_power: instance %d: " 580 "can't locate new CPU speed", instance); 581 return (DDI_FAILURE); 582 } 583 584 /* 585 * We currently refuse to power manage if the CPU is not ready to 586 * take cross calls (cross calls fail silently if CPU is not ready 587 * for it). 588 * 589 * Additionally, for x86 platforms we cannot power manage an instance, 590 * until it has been initialized. 591 */ 592 if (is_ready) { 593 is_ready = CPUDRV_XCALL_IS_READY(cpudsp->cpu_id); 594 if (!is_ready) { 595 DPRINTF(D_POWER, ("cpudrv_power: instance %d: " 596 "CPU not ready for x-calls\n", instance)); 597 } else if (!(is_ready = cpudrv_power_ready(cpudsp->cp))) { 598 DPRINTF(D_POWER, ("cpudrv_power: instance %d: " 599 "waiting for all CPUs to be power manageable\n", 600 instance)); 601 } 602 } 603 if (!is_ready) { 604 CPUDRV_RESET_GOVERNOR_THREAD(cpudrvpm); 605 mutex_exit(&cpudsp->lock); 606 return (DDI_FAILURE); 607 } 608 609 /* 610 * Execute CPU specific routine on the requested CPU to 611 * change its speed to normal-speed/divisor. 612 */ 613 if ((ret = cpudrv_change_speed(cpudsp, new_spd)) != DDI_SUCCESS) { 614 cmn_err(CE_WARN, "cpudrv_power: " 615 "cpudrv_change_speed() return = %d", ret); 616 mutex_exit(&cpudsp->lock); 617 return (DDI_FAILURE); 618 } 619 620 /* 621 * Reset idle threshold time for the new power level. 622 */ 623 if ((cpudrvpm->cur_spd != NULL) && (level < 624 cpudrvpm->cur_spd->pm_level)) { 625 if (pm_idle_component(dip, CPUDRV_COMP_NUM) == 626 DDI_SUCCESS) { 627 if (cpudrvpm->pm_busycnt >= 1) 628 cpudrvpm->pm_busycnt--; 629 } else { 630 cmn_err(CE_WARN, "cpudrv_power: instance %d: " 631 "can't idle CPU component", 632 ddi_get_instance(dip)); 633 } 634 } 635 /* 636 * Reset various parameters because we are now running at new speed. 637 */ 638 cpudrvpm->lastquan_mstate[CMS_IDLE] = 0; 639 cpudrvpm->lastquan_mstate[CMS_SYSTEM] = 0; 640 cpudrvpm->lastquan_mstate[CMS_USER] = 0; 641 cpudrvpm->lastquan_ticks = 0; 642 cpudrvpm->cur_spd = new_spd; 643 CPUDRV_RESET_GOVERNOR_THREAD(cpudrvpm); 644 mutex_exit(&cpudsp->lock); 645 646 return (DDI_SUCCESS); 647 } 648 649 /* 650 * Initialize power management data. 651 */ 652 static int 653 cpudrv_init(cpudrv_devstate_t *cpudsp) 654 { 655 cpudrv_pm_t *cpupm = &(cpudsp->cpudrv_pm); 656 cpudrv_pm_spd_t *cur_spd; 657 cpudrv_pm_spd_t *prev_spd = NULL; 658 int *speeds; 659 uint_t nspeeds; 660 int idle_cnt_percent; 661 int user_cnt_percent; 662 int i; 663 664 CPUDRV_GET_SPEEDS(cpudsp, speeds, nspeeds); 665 if (nspeeds < 2) { 666 /* Need at least two speeds to power manage */ 667 CPUDRV_FREE_SPEEDS(speeds, nspeeds); 668 return (DDI_FAILURE); 669 } 670 cpupm->num_spd = nspeeds; 671 672 /* 673 * Calculate the watermarks and other parameters based on the 674 * supplied speeds. 675 * 676 * One of the basic assumption is that for X amount of CPU work, 677 * if CPU is slowed down by a factor of N, the time it takes to 678 * do the same work will be N * X. 679 * 680 * The driver declares that a CPU is idle and ready for slowed down, 681 * if amount of idle thread is more than the current speed idle_hwm 682 * without dropping below idle_hwm a number of consecutive sampling 683 * intervals and number of running threads in user mode are below 684 * user_lwm. We want to set the current user_lwm such that if we 685 * just switched to the next slower speed with no change in real work 686 * load, the amount of user threads at the slower speed will be such 687 * that it falls below the slower speed's user_hwm. If we didn't do 688 * that then we will just come back to the higher speed as soon as we 689 * go down even with no change in work load. 690 * The user_hwm is a fixed precentage and not calculated dynamically. 691 * 692 * We bring the CPU up if idle thread at current speed is less than 693 * the current speed idle_lwm for a number of consecutive sampling 694 * intervals or user threads are above the user_hwm for the current 695 * speed. 696 */ 697 for (i = 0; i < nspeeds; i++) { 698 cur_spd = kmem_zalloc(sizeof (cpudrv_pm_spd_t), KM_SLEEP); 699 cur_spd->speed = speeds[i]; 700 if (i == 0) { /* normal speed */ 701 cpupm->head_spd = cur_spd; 702 CPUDRV_TOPSPEED(cpupm) = cur_spd; 703 cur_spd->quant_cnt = CPUDRV_QUANT_CNT_NORMAL; 704 cur_spd->idle_hwm = 705 (cpudrv_idle_hwm * cur_spd->quant_cnt) / 100; 706 /* can't speed anymore */ 707 cur_spd->idle_lwm = 0; 708 cur_spd->user_hwm = UINT_MAX; 709 } else { 710 cur_spd->quant_cnt = CPUDRV_QUANT_CNT_OTHR; 711 ASSERT(prev_spd != NULL); 712 prev_spd->down_spd = cur_spd; 713 cur_spd->up_spd = cpupm->head_spd; 714 715 /* 716 * Let's assume CPU is considered idle at full speed 717 * when it is spending I% of time in running the idle 718 * thread. At full speed, CPU will be busy (100 - I) % 719 * of times. This % of busyness increases by factor of 720 * N as CPU slows down. CPU that is idle I% of times 721 * in full speed, it is idle (100 - ((100 - I) * N)) % 722 * of times in N speed. The idle_lwm is a fixed 723 * percentage. A large value of N may result in 724 * idle_hwm to go below idle_lwm. We need to make sure 725 * that there is at least a buffer zone seperation 726 * between the idle_lwm and idle_hwm values. 727 */ 728 idle_cnt_percent = CPUDRV_IDLE_CNT_PERCENT( 729 cpudrv_idle_hwm, speeds, i); 730 idle_cnt_percent = max(idle_cnt_percent, 731 (cpudrv_idle_lwm + cpudrv_idle_buf_zone)); 732 cur_spd->idle_hwm = 733 (idle_cnt_percent * cur_spd->quant_cnt) / 100; 734 cur_spd->idle_lwm = 735 (cpudrv_idle_lwm * cur_spd->quant_cnt) / 100; 736 737 /* 738 * The lwm for user threads are determined such that 739 * if CPU slows down, the load of work in the 740 * new speed would still keep the CPU at or below the 741 * user_hwm in the new speed. This is to prevent 742 * the quick jump back up to higher speed. 743 */ 744 cur_spd->user_hwm = (cpudrv_user_hwm * 745 cur_spd->quant_cnt) / 100; 746 user_cnt_percent = CPUDRV_USER_CNT_PERCENT( 747 cpudrv_user_hwm, speeds, i); 748 prev_spd->user_lwm = 749 (user_cnt_percent * prev_spd->quant_cnt) / 100; 750 } 751 prev_spd = cur_spd; 752 } 753 /* Slowest speed. Can't slow down anymore */ 754 cur_spd->idle_hwm = UINT_MAX; 755 cur_spd->user_lwm = -1; 756 #ifdef DEBUG 757 DPRINTF(D_PM_INIT, ("cpudrv_init: instance %d: head_spd spd %d, " 758 "num_spd %d\n", ddi_get_instance(cpudsp->dip), 759 cpupm->head_spd->speed, cpupm->num_spd)); 760 for (cur_spd = cpupm->head_spd; cur_spd; cur_spd = cur_spd->down_spd) { 761 DPRINTF(D_PM_INIT, ("cpudrv_init: instance %d: speed %d, " 762 "down_spd spd %d, idle_hwm %d, user_lwm %d, " 763 "up_spd spd %d, idle_lwm %d, user_hwm %d, " 764 "quant_cnt %d\n", ddi_get_instance(cpudsp->dip), 765 cur_spd->speed, 766 (cur_spd->down_spd ? cur_spd->down_spd->speed : 0), 767 cur_spd->idle_hwm, cur_spd->user_lwm, 768 (cur_spd->up_spd ? cur_spd->up_spd->speed : 0), 769 cur_spd->idle_lwm, cur_spd->user_hwm, 770 cur_spd->quant_cnt)); 771 } 772 #endif /* DEBUG */ 773 CPUDRV_FREE_SPEEDS(speeds, nspeeds); 774 return (DDI_SUCCESS); 775 } 776 777 /* 778 * Free CPU power management data. 779 */ 780 static void 781 cpudrv_free(cpudrv_devstate_t *cpudsp) 782 { 783 cpudrv_pm_t *cpupm = &(cpudsp->cpudrv_pm); 784 cpudrv_pm_spd_t *cur_spd, *next_spd; 785 786 cur_spd = cpupm->head_spd; 787 while (cur_spd) { 788 next_spd = cur_spd->down_spd; 789 kmem_free(cur_spd, sizeof (cpudrv_pm_spd_t)); 790 cur_spd = next_spd; 791 } 792 bzero(cpupm, sizeof (cpudrv_pm_t)); 793 } 794 795 /* 796 * Create pm-components property. 797 */ 798 static int 799 cpudrv_comp_create(cpudrv_devstate_t *cpudsp) 800 { 801 cpudrv_pm_t *cpupm = &(cpudsp->cpudrv_pm); 802 cpudrv_pm_spd_t *cur_spd; 803 char **pmc; 804 int size; 805 char name[] = "NAME=CPU Speed"; 806 int i, j; 807 uint_t comp_spd; 808 int result = DDI_FAILURE; 809 810 pmc = kmem_zalloc((cpupm->num_spd + 1) * sizeof (char *), KM_SLEEP); 811 size = CPUDRV_COMP_SIZE(); 812 if (cpupm->num_spd > CPUDRV_COMP_MAX_VAL) { 813 cmn_err(CE_WARN, "cpudrv_comp_create: instance %d: " 814 "number of speeds exceeded limits", 815 ddi_get_instance(cpudsp->dip)); 816 kmem_free(pmc, (cpupm->num_spd + 1) * sizeof (char *)); 817 return (result); 818 } 819 820 for (i = cpupm->num_spd, cur_spd = cpupm->head_spd; i > 0; 821 i--, cur_spd = cur_spd->down_spd) { 822 cur_spd->pm_level = i; 823 pmc[i] = kmem_zalloc((size * sizeof (char)), KM_SLEEP); 824 comp_spd = CPUDRV_COMP_SPEED(cpupm, cur_spd); 825 if (comp_spd > CPUDRV_COMP_MAX_VAL) { 826 cmn_err(CE_WARN, "cpudrv_comp_create: " 827 "instance %d: speed exceeded limits", 828 ddi_get_instance(cpudsp->dip)); 829 for (j = cpupm->num_spd; j >= i; j--) { 830 kmem_free(pmc[j], size * sizeof (char)); 831 } 832 kmem_free(pmc, (cpupm->num_spd + 1) * 833 sizeof (char *)); 834 return (result); 835 } 836 CPUDRV_COMP_SPRINT(pmc[i], cpupm, cur_spd, comp_spd) 837 DPRINTF(D_PM_COMP_CREATE, ("cpudrv_comp_create: " 838 "instance %d: pm-components power level %d string '%s'\n", 839 ddi_get_instance(cpudsp->dip), i, pmc[i])); 840 } 841 pmc[0] = kmem_zalloc(sizeof (name), KM_SLEEP); 842 (void) strcat(pmc[0], name); 843 DPRINTF(D_PM_COMP_CREATE, ("cpudrv_comp_create: instance %d: " 844 "pm-components component name '%s'\n", 845 ddi_get_instance(cpudsp->dip), pmc[0])); 846 847 if (ddi_prop_update_string_array(DDI_DEV_T_NONE, cpudsp->dip, 848 "pm-components", pmc, cpupm->num_spd + 1) == DDI_PROP_SUCCESS) { 849 result = DDI_SUCCESS; 850 } else { 851 cmn_err(CE_WARN, "cpudrv_comp_create: instance %d: " 852 "can't create pm-components property", 853 ddi_get_instance(cpudsp->dip)); 854 } 855 856 for (i = cpupm->num_spd; i > 0; i--) { 857 kmem_free(pmc[i], size * sizeof (char)); 858 } 859 kmem_free(pmc[0], sizeof (name)); 860 kmem_free(pmc, (cpupm->num_spd + 1) * sizeof (char *)); 861 return (result); 862 } 863 864 /* 865 * Mark a component idle. 866 */ 867 #define CPUDRV_MONITOR_PM_IDLE_COMP(dip, cpupm) { \ 868 if ((cpupm)->pm_busycnt >= 1) { \ 869 if (pm_idle_component((dip), CPUDRV_COMP_NUM) == \ 870 DDI_SUCCESS) { \ 871 DPRINTF(D_PM_MONITOR, ("cpudrv_monitor: " \ 872 "instance %d: pm_idle_component called\n", \ 873 ddi_get_instance((dip)))); \ 874 (cpupm)->pm_busycnt--; \ 875 } else { \ 876 cmn_err(CE_WARN, "cpudrv_monitor: instance %d: " \ 877 "can't idle CPU component", \ 878 ddi_get_instance((dip))); \ 879 } \ 880 } \ 881 } 882 883 /* 884 * Marks a component busy in both PM framework and driver state structure. 885 */ 886 #define CPUDRV_MONITOR_PM_BUSY_COMP(dip, cpupm) { \ 887 if ((cpupm)->pm_busycnt < 1) { \ 888 if (pm_busy_component((dip), CPUDRV_COMP_NUM) == \ 889 DDI_SUCCESS) { \ 890 DPRINTF(D_PM_MONITOR, ("cpudrv_monitor: " \ 891 "instance %d: pm_busy_component called\n", \ 892 ddi_get_instance((dip)))); \ 893 (cpupm)->pm_busycnt++; \ 894 } else { \ 895 cmn_err(CE_WARN, "cpudrv_monitor: instance %d: " \ 896 "can't busy CPU component", \ 897 ddi_get_instance((dip))); \ 898 } \ 899 } \ 900 } 901 902 /* 903 * Marks a component busy and calls pm_raise_power(). 904 */ 905 #define CPUDRV_MONITOR_PM_BUSY_AND_RAISE(dip, cpudsp, cpupm, new_spd) { \ 906 int ret; \ 907 /* \ 908 * Mark driver and PM framework busy first so framework doesn't try \ 909 * to bring CPU to lower speed when we need to be at higher speed. \ 910 */ \ 911 CPUDRV_MONITOR_PM_BUSY_COMP((dip), (cpupm)); \ 912 mutex_exit(&(cpudsp)->lock); \ 913 DPRINTF(D_PM_MONITOR, ("cpudrv_monitor: instance %d: " \ 914 "pm_raise_power called to %d\n", ddi_get_instance((dip)), \ 915 (new_spd->pm_level))); \ 916 ret = pm_raise_power((dip), CPUDRV_COMP_NUM, (new_spd->pm_level)); \ 917 if (ret != DDI_SUCCESS) { \ 918 cmn_err(CE_WARN, "cpudrv_monitor: instance %d: can't " \ 919 "raise CPU power level", ddi_get_instance((dip))); \ 920 } \ 921 mutex_enter(&(cpudsp)->lock); \ 922 if (ret == DDI_SUCCESS && cpudsp->cpudrv_pm.cur_spd == NULL) { \ 923 cpudsp->cpudrv_pm.cur_spd = new_spd; \ 924 } \ 925 } 926 927 /* 928 * In order to monitor a CPU, we need to hold cpu_lock to access CPU 929 * statistics. Holding cpu_lock is not allowed from a callout routine. 930 * We dispatch a taskq to do that job. 931 */ 932 static void 933 cpudrv_monitor_disp(void *arg) 934 { 935 cpudrv_devstate_t *cpudsp = (cpudrv_devstate_t *)arg; 936 937 /* 938 * We are here because the last task has scheduled a timeout. 939 * The queue should be empty at this time. 940 */ 941 mutex_enter(&cpudsp->cpudrv_pm.timeout_lock); 942 if ((ddi_taskq_dispatch(cpudsp->cpudrv_pm.tq, cpudrv_monitor, arg, 943 DDI_NOSLEEP)) != DDI_SUCCESS) { 944 mutex_exit(&cpudsp->cpudrv_pm.timeout_lock); 945 DPRINTF(D_PM_MONITOR, ("cpudrv_monitor_disp: failed to " 946 "dispatch the cpudrv_monitor taskq\n")); 947 mutex_enter(&cpudsp->lock); 948 CPUDRV_MONITOR_INIT(cpudsp); 949 mutex_exit(&cpudsp->lock); 950 return; 951 } 952 cpudsp->cpudrv_pm.timeout_count++; 953 mutex_exit(&cpudsp->cpudrv_pm.timeout_lock); 954 } 955 956 /* 957 * Monitors each CPU for the amount of time idle thread was running in the 958 * last quantum and arranges for the CPU to go to the lower or higher speed. 959 * Called at the time interval appropriate for the current speed. The 960 * time interval for normal speed is CPUDRV_QUANT_CNT_NORMAL. The time 961 * interval for other speeds (including unknown speed) is 962 * CPUDRV_QUANT_CNT_OTHR. 963 */ 964 static void 965 cpudrv_monitor(void *arg) 966 { 967 cpudrv_devstate_t *cpudsp = (cpudrv_devstate_t *)arg; 968 cpudrv_pm_t *cpupm; 969 cpudrv_pm_spd_t *cur_spd, *new_spd; 970 dev_info_t *dip; 971 uint_t idle_cnt, user_cnt, system_cnt; 972 clock_t ticks; 973 uint_t tick_cnt; 974 hrtime_t msnsecs[NCMSTATES]; 975 boolean_t is_ready; 976 977 #define GET_CPU_MSTATE_CNT(state, cnt) \ 978 msnsecs[state] = NSEC_TO_TICK(msnsecs[state]); \ 979 if (cpupm->lastquan_mstate[state] > msnsecs[state]) \ 980 msnsecs[state] = cpupm->lastquan_mstate[state]; \ 981 cnt = msnsecs[state] - cpupm->lastquan_mstate[state]; \ 982 cpupm->lastquan_mstate[state] = msnsecs[state] 983 984 /* 985 * We're not ready until we can get a cpu_t 986 */ 987 is_ready = (cpudrv_get_cpu(cpudsp) == DDI_SUCCESS); 988 989 mutex_enter(&cpudsp->lock); 990 cpupm = &(cpudsp->cpudrv_pm); 991 if (cpupm->timeout_id == 0) { 992 mutex_exit(&cpudsp->lock); 993 goto do_return; 994 } 995 cur_spd = cpupm->cur_spd; 996 dip = cpudsp->dip; 997 998 /* 999 * We assume that a CPU is initialized and has a valid cpu_t 1000 * structure, if it is ready for cross calls. If this changes, 1001 * additional checks might be needed. 1002 * 1003 * Additionally, for x86 platforms we cannot power manage an 1004 * instance, until it has been initialized. 1005 */ 1006 if (is_ready) { 1007 is_ready = CPUDRV_XCALL_IS_READY(cpudsp->cpu_id); 1008 if (!is_ready) { 1009 DPRINTF(D_PM_MONITOR, ("cpudrv_monitor: instance %d: " 1010 "CPU not ready for x-calls\n", 1011 ddi_get_instance(dip))); 1012 } else if (!(is_ready = cpudrv_power_ready(cpudsp->cp))) { 1013 DPRINTF(D_PM_MONITOR, ("cpudrv_monitor: instance %d: " 1014 "waiting for all CPUs to be power manageable\n", 1015 ddi_get_instance(dip))); 1016 } 1017 } 1018 if (!is_ready) { 1019 /* 1020 * Make sure that we are busy so that framework doesn't 1021 * try to bring us down in this situation. 1022 */ 1023 CPUDRV_MONITOR_PM_BUSY_COMP(dip, cpupm); 1024 CPUDRV_MONITOR_INIT(cpudsp); 1025 mutex_exit(&cpudsp->lock); 1026 goto do_return; 1027 } 1028 1029 /* 1030 * Make sure that we are still not at unknown power level. 1031 */ 1032 if (cur_spd == NULL) { 1033 DPRINTF(D_PM_MONITOR, ("cpudrv_monitor: instance %d: " 1034 "cur_spd is unknown\n", ddi_get_instance(dip))); 1035 CPUDRV_MONITOR_PM_BUSY_AND_RAISE(dip, cpudsp, cpupm, 1036 CPUDRV_TOPSPEED(cpupm)); 1037 /* 1038 * We just changed the speed. Wait till at least next 1039 * call to this routine before proceeding ahead. 1040 */ 1041 CPUDRV_MONITOR_INIT(cpudsp); 1042 mutex_exit(&cpudsp->lock); 1043 goto do_return; 1044 } 1045 1046 if (!cpupm->pm_started) { 1047 cpupm->pm_started = B_TRUE; 1048 cpudrv_set_supp_freqs(cpudsp); 1049 } 1050 1051 get_cpu_mstate(cpudsp->cp, msnsecs); 1052 GET_CPU_MSTATE_CNT(CMS_IDLE, idle_cnt); 1053 GET_CPU_MSTATE_CNT(CMS_USER, user_cnt); 1054 GET_CPU_MSTATE_CNT(CMS_SYSTEM, system_cnt); 1055 1056 /* 1057 * We can't do anything when we have just switched to a state 1058 * because there is no valid timestamp. 1059 */ 1060 if (cpupm->lastquan_ticks == 0) { 1061 cpupm->lastquan_ticks = NSEC_TO_TICK(gethrtime()); 1062 CPUDRV_MONITOR_INIT(cpudsp); 1063 mutex_exit(&cpudsp->lock); 1064 goto do_return; 1065 } 1066 1067 /* 1068 * Various watermarks are based on this routine being called back 1069 * exactly at the requested period. This is not guaranteed 1070 * because this routine is called from a taskq that is dispatched 1071 * from a timeout routine. Handle this by finding out how many 1072 * ticks have elapsed since the last call and adjusting 1073 * the idle_cnt based on the delay added to the requested period 1074 * by timeout and taskq. 1075 */ 1076 ticks = NSEC_TO_TICK(gethrtime()); 1077 tick_cnt = ticks - cpupm->lastquan_ticks; 1078 ASSERT(tick_cnt != 0); 1079 cpupm->lastquan_ticks = ticks; 1080 1081 /* 1082 * Time taken between recording the current counts and 1083 * arranging the next call of this routine is an error in our 1084 * calculation. We minimize the error by calling 1085 * CPUDRV_MONITOR_INIT() here instead of end of this routine. 1086 */ 1087 CPUDRV_MONITOR_INIT(cpudsp); 1088 DPRINTF(D_PM_MONITOR_VERBOSE, ("cpudrv_monitor: instance %d: " 1089 "idle count %d, user count %d, system count %d, pm_level %d, " 1090 "pm_busycnt %d\n", ddi_get_instance(dip), idle_cnt, user_cnt, 1091 system_cnt, cur_spd->pm_level, cpupm->pm_busycnt)); 1092 1093 #ifdef DEBUG 1094 /* 1095 * Notify that timeout and taskq has caused delays and we need to 1096 * scale our parameters accordingly. 1097 * 1098 * To get accurate result, don't turn on other DPRINTFs with 1099 * the following DPRINTF. PROM calls generated by other 1100 * DPRINTFs changes the timing. 1101 */ 1102 if (tick_cnt > cur_spd->quant_cnt) { 1103 DPRINTF(D_PM_MONITOR_DELAY, ("cpudrv_monitor: instance %d: " 1104 "tick count %d > quantum_count %u\n", 1105 ddi_get_instance(dip), tick_cnt, cur_spd->quant_cnt)); 1106 } 1107 #endif /* DEBUG */ 1108 1109 /* 1110 * Adjust counts based on the delay added by timeout and taskq. 1111 */ 1112 idle_cnt = (idle_cnt * cur_spd->quant_cnt) / tick_cnt; 1113 user_cnt = (user_cnt * cur_spd->quant_cnt) / tick_cnt; 1114 1115 if ((user_cnt > cur_spd->user_hwm) || (idle_cnt < cur_spd->idle_lwm && 1116 cur_spd->idle_blwm_cnt >= cpudrv_idle_blwm_cnt_max)) { 1117 cur_spd->idle_blwm_cnt = 0; 1118 cur_spd->idle_bhwm_cnt = 0; 1119 /* 1120 * In normal situation, arrange to go to next higher speed. 1121 * If we are running in special direct pm mode, we just stay 1122 * at the current speed. 1123 */ 1124 if (cur_spd == cur_spd->up_spd || cpudrv_direct_pm) { 1125 CPUDRV_MONITOR_PM_BUSY_COMP(dip, cpupm); 1126 } else { 1127 new_spd = cur_spd->up_spd; 1128 CPUDRV_MONITOR_PM_BUSY_AND_RAISE(dip, cpudsp, cpupm, 1129 new_spd); 1130 } 1131 } else if ((user_cnt <= cur_spd->user_lwm) && 1132 (idle_cnt >= cur_spd->idle_hwm) || !CPU_ACTIVE(cpudsp->cp)) { 1133 cur_spd->idle_blwm_cnt = 0; 1134 cur_spd->idle_bhwm_cnt = 0; 1135 /* 1136 * Arrange to go to next lower speed by informing our idle 1137 * status to the power management framework. 1138 */ 1139 CPUDRV_MONITOR_PM_IDLE_COMP(dip, cpupm); 1140 } else { 1141 /* 1142 * If we are between the idle water marks and have not 1143 * been here enough consecutive times to be considered 1144 * busy, just increment the count and return. 1145 */ 1146 if ((idle_cnt < cur_spd->idle_hwm) && 1147 (idle_cnt >= cur_spd->idle_lwm) && 1148 (cur_spd->idle_bhwm_cnt < cpudrv_idle_bhwm_cnt_max)) { 1149 cur_spd->idle_blwm_cnt = 0; 1150 cur_spd->idle_bhwm_cnt++; 1151 mutex_exit(&cpudsp->lock); 1152 goto do_return; 1153 } 1154 if (idle_cnt < cur_spd->idle_lwm) { 1155 cur_spd->idle_blwm_cnt++; 1156 cur_spd->idle_bhwm_cnt = 0; 1157 } 1158 /* 1159 * Arranges to stay at the current speed. 1160 */ 1161 CPUDRV_MONITOR_PM_BUSY_COMP(dip, cpupm); 1162 } 1163 mutex_exit(&cpudsp->lock); 1164 do_return: 1165 mutex_enter(&cpupm->timeout_lock); 1166 ASSERT(cpupm->timeout_count > 0); 1167 cpupm->timeout_count--; 1168 cv_signal(&cpupm->timeout_cv); 1169 mutex_exit(&cpupm->timeout_lock); 1170 } 1171 1172 /* 1173 * get cpu_t structure for cpudrv_devstate_t 1174 */ 1175 int 1176 cpudrv_get_cpu(cpudrv_devstate_t *cpudsp) 1177 { 1178 ASSERT(cpudsp != NULL); 1179 1180 /* 1181 * return DDI_SUCCESS if cpudrv_devstate_t 1182 * already contains cpu_t structure 1183 */ 1184 if (cpudsp->cp != NULL) 1185 return (DDI_SUCCESS); 1186 1187 if (MUTEX_HELD(&cpu_lock)) { 1188 cpudsp->cp = cpu_get(cpudsp->cpu_id); 1189 } else { 1190 mutex_enter(&cpu_lock); 1191 cpudsp->cp = cpu_get(cpudsp->cpu_id); 1192 mutex_exit(&cpu_lock); 1193 } 1194 1195 if (cpudsp->cp == NULL) 1196 return (DDI_FAILURE); 1197 1198 return (DDI_SUCCESS); 1199 } 1200
Indexes created Tue Nov 24 23:02:35 UTC 2009
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