sys/x86/cpufreq/hwpstate_intel.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
   3  *
   4  * Copyright (c) 2018 Intel Corporation
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted providing that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR``AS IS'' AND ANY EXPRESS OR
  16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  17  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
  19  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  23  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  24  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  25  * POSSIBILITY OF SUCH DAMAGE.
  26  */
  27
  28 #include <sys/cdefs.h>
  29 __FBSDID("$FreeBSD$");
  30
  31 #include <sys/types.h>
  32 #include <sys/sbuf.h>
  33 #include <sys/module.h>
  34 #include <sys/systm.h>
  35 #include <sys/errno.h>
  36 #include <sys/param.h>
  37 #include <sys/kernel.h>
  38 #include <sys/bus.h>
  39 #include <sys/cpu.h>
  40 #include <sys/smp.h>
  41 #include <sys/proc.h>
  42 #include <sys/sched.h>
  43
  44 #include <machine/cpu.h>
  45 #include <machine/md_var.h>
  46 #include <machine/cputypes.h>
  47 #include <machine/specialreg.h>
  48
  49 #include <contrib/dev/acpica/include/acpi.h>
  50
  51 #include <dev/acpica/acpivar.h>
  52
  53 #include <x86/cpufreq/hwpstate_intel_internal.h>
  54
  55 #include "acpi_if.h"
  56 #include "cpufreq_if.h"
  57
  58 extern uint64_t tsc_freq;
  59
  60 static int      intel_hwpstate_probe(device_t dev);
  61 static int      intel_hwpstate_attach(device_t dev);
  62 static int      intel_hwpstate_detach(device_t dev);
  63 static int      intel_hwpstate_suspend(device_t dev);
  64 static int      intel_hwpstate_resume(device_t dev);
  65
  66 static int      intel_hwpstate_get(device_t dev, struct cf_setting *cf);
  67 static int      intel_hwpstate_type(device_t dev, int *type);
  68
  69 static device_method_t intel_hwpstate_methods[] = {
  70         /* Device interface */
  71         DEVMETHOD(device_identify,      intel_hwpstate_identify),
  72         DEVMETHOD(device_probe,         intel_hwpstate_probe),
  73         DEVMETHOD(device_attach,        intel_hwpstate_attach),
  74         DEVMETHOD(device_detach,        intel_hwpstate_detach),
  75         DEVMETHOD(device_suspend,       intel_hwpstate_suspend),
  76         DEVMETHOD(device_resume,        intel_hwpstate_resume),
  77
  78         /* cpufreq interface */
  79         DEVMETHOD(cpufreq_drv_get,      intel_hwpstate_get),
  80         DEVMETHOD(cpufreq_drv_type,     intel_hwpstate_type),
  81
  82         DEVMETHOD_END
  83 };
  84
  85 struct hwp_softc {
  86         device_t                dev;
  87         bool                    hwp_notifications;
  88         bool                    hwp_activity_window;
  89         bool                    hwp_pref_ctrl;
  90         bool                    hwp_pkg_ctrl;
  91         bool                    hwp_pkg_ctrl_en;
  92         bool                    hwp_perf_bias;
  93         bool                    hwp_perf_bias_cached;
  94
  95         uint64_t                req; /* Cached copy of HWP_REQUEST */
  96         uint64_t                hwp_energy_perf_bias;   /* Cache PERF_BIAS */
  97
  98         uint8_t                 high;
  99         uint8_t                 guaranteed;
 100         uint8_t                 efficient;
 101         uint8_t                 low;
 102 };
 103
 104 static devclass_t hwpstate_intel_devclass;
 105 static driver_t hwpstate_intel_driver = {
 106         "hwpstate_intel",
 107         intel_hwpstate_methods,
 108         sizeof(struct hwp_softc),
 109 };
 110
 111 DRIVER_MODULE(hwpstate_intel, cpu, hwpstate_intel_driver,
 112     hwpstate_intel_devclass, NULL, NULL);
 113 MODULE_VERSION(hwpstate_intel, 1);
 114
 115 static bool hwpstate_pkg_ctrl_enable = true;
 116 SYSCTL_BOOL(_machdep, OID_AUTO, hwpstate_pkg_ctrl, CTLFLAG_RDTUN,
 117     &hwpstate_pkg_ctrl_enable, 0,
 118     "Set 1 (default) to enable package-level control, 0 to disable");
 119
 120 static int
 121 intel_hwp_dump_sysctl_handler(SYSCTL_HANDLER_ARGS)
 122 {
 123         device_t dev;
 124         struct pcpu *pc;
 125         struct sbuf *sb;
 126         struct hwp_softc *sc;
 127         uint64_t data, data2;
 128         int ret;
 129
 130         sc = (struct hwp_softc *)arg1;
 131         dev = sc->dev;
 132
 133         pc = cpu_get_pcpu(dev);
 134         if (pc == NULL)
 135                 return (ENXIO);
 136
 137         sb = sbuf_new(NULL, NULL, 1024, SBUF_FIXEDLEN | SBUF_INCLUDENUL);
 138         sbuf_putc(sb, '\n');
 139         thread_lock(curthread);
 140         sched_bind(curthread, pc->pc_cpuid);
 141         thread_unlock(curthread);
 142
 143         rdmsr_safe(MSR_IA32_PM_ENABLE, &data);
 144         sbuf_printf(sb, "CPU%d: HWP %sabled\n", pc->pc_cpuid,
 145             ((data & 1) ? "En" : "Dis"));
 146
 147         if (data == 0) {
 148                 ret = 0;
 149                 goto out;
 150         }
 151
 152         rdmsr_safe(MSR_IA32_HWP_CAPABILITIES, &data);
 153         sbuf_printf(sb, "\tHighest Performance: %03ju\n", data & 0xff);
 154         sbuf_printf(sb, "\tGuaranteed Performance: %03ju\n", (data >> 8) & 0xff);
 155         sbuf_printf(sb, "\tEfficient Performance: %03ju\n", (data >> 16) & 0xff);
 156         sbuf_printf(sb, "\tLowest Performance: %03ju\n", (data >> 24) & 0xff);
 157
 158         rdmsr_safe(MSR_IA32_HWP_REQUEST, &data);
 159         data2 = 0;
 160         if (sc->hwp_pkg_ctrl && (data & IA32_HWP_REQUEST_PACKAGE_CONTROL))
 161                 rdmsr_safe(MSR_IA32_HWP_REQUEST_PKG, &data2);
 162
 163         sbuf_putc(sb, '\n');
 164
 165 #define pkg_print(x, name, offset) do {                                 \
 166         if (!sc->hwp_pkg_ctrl || (data & x) != 0)                       \
 167                 sbuf_printf(sb, "\t%s: %03u\n", name,                   \
 168                     (unsigned)(data >> offset) & 0xff);                 \
 169         else                                                            \
 170                 sbuf_printf(sb, "\t%s: %03u\n", name,                   \
 171                     (unsigned)(data2 >> offset) & 0xff);                \
 172 } while (0)
 173
 174         pkg_print(IA32_HWP_REQUEST_EPP_VALID,
 175             "Requested Efficiency Performance Preference", 24);
 176         pkg_print(IA32_HWP_REQUEST_DESIRED_VALID,
 177             "Requested Desired Performance", 16);
 178         pkg_print(IA32_HWP_REQUEST_MAXIMUM_VALID,
 179             "Requested Maximum Performance", 8);
 180         pkg_print(IA32_HWP_REQUEST_MINIMUM_VALID,
 181             "Requested Minimum Performance", 0);
 182 #undef pkg_print
 183
 184         sbuf_putc(sb, '\n');
 185
 186 out:
 187         thread_lock(curthread);
 188         sched_unbind(curthread);
 189         thread_unlock(curthread);
 190
 191         ret = sbuf_finish(sb);
 192         if (ret == 0)
 193                 ret = SYSCTL_OUT(req, sbuf_data(sb), sbuf_len(sb));
 194         sbuf_delete(sb);
 195
 196         return (ret);
 197 }
 198
 199 static inline int
 200 percent_to_raw(int x)
 201 {
 202
 203         MPASS(x <= 100 && x >= 0);
 204         return (0xff * x / 100);
 205 }
 206
 207 /*
 208  * Given x * 10 in [0, 1000], round to the integer nearest x.
 209  *
 210  * This allows round-tripping nice human readable numbers through this
 211  * interface.  Otherwise, user-provided percentages such as 25, 50, 75 get
 212  * rounded down to 24, 49, and 74, which is a bit ugly.
 213  */
 214 static inline int
 215 round10(int xtimes10)
 216 {
 217         return ((xtimes10 + 5) / 10);
 218 }
 219
 220 static inline int
 221 raw_to_percent(int x)
 222 {
 223         MPASS(x <= 0xff && x >= 0);
 224         return (round10(x * 1000 / 0xff));
 225 }
 226
 227 /* Range of MSR_IA32_ENERGY_PERF_BIAS is more limited: 0-0xf. */
 228 static inline int
 229 percent_to_raw_perf_bias(int x)
 230 {
 231         /*
 232          * Round up so that raw values present as nice round human numbers and
 233          * also round-trip to the same raw value.
 234          */
 235         MPASS(x <= 100 && x >= 0);
 236         return (((0xf * x) + 50) / 100);
 237 }
 238
 239 static inline int
 240 raw_to_percent_perf_bias(int x)
 241 {
 242         /* Rounding to nice human numbers despite a step interval of 6.67%. */
 243         MPASS(x <= 0xf && x >= 0);
 244         return (((x * 20) / 0xf) * 5);
 245 }
 246
 247 static int
 248 sysctl_epp_select(SYSCTL_HANDLER_ARGS)
 249 {
 250         struct hwp_softc *sc;
 251         device_t dev;
 252         struct pcpu *pc;
 253         uint64_t epb;
 254         uint32_t val;
 255         int ret;
 256
 257         dev = oidp->oid_arg1;
 258         sc = device_get_softc(dev);
 259         if (!sc->hwp_pref_ctrl && !sc->hwp_perf_bias)
 260                 return (ENODEV);
 261
 262         pc = cpu_get_pcpu(dev);
 263         if (pc == NULL)
 264                 return (ENXIO);
 265
 266         thread_lock(curthread);
 267         sched_bind(curthread, pc->pc_cpuid);
 268         thread_unlock(curthread);
 269
 270         if (sc->hwp_pref_ctrl) {
 271                 val = (sc->req & IA32_HWP_REQUEST_ENERGY_PERFORMANCE_PREFERENCE) >> 24;
 272                 val = raw_to_percent(val);
 273         } else {
 274                 /*
 275                  * If cpuid indicates EPP is not supported, the HWP controller
 276                  * uses MSR_IA32_ENERGY_PERF_BIAS instead (Intel SDM §14.4.4).
 277                  * This register is per-core (but not HT).
 278                  */
 279                 if (!sc->hwp_perf_bias_cached) {
 280                         ret = rdmsr_safe(MSR_IA32_ENERGY_PERF_BIAS, &epb);
 281                         if (ret)
 282                                 goto out;
 283                         sc->hwp_energy_perf_bias = epb;
 284                         sc->hwp_perf_bias_cached = true;
 285                 }
 286                 val = sc->hwp_energy_perf_bias &
 287                     IA32_ENERGY_PERF_BIAS_POLICY_HINT_MASK;
 288                 val = raw_to_percent_perf_bias(val);
 289         }
 290
 291         MPASS(val >= 0 && val <= 100);
 292
 293         ret = sysctl_handle_int(oidp, &val, 0, req);
 294         if (ret || req->newptr == NULL)
 295                 goto out;
 296
 297         if (val > 100) {
 298                 ret = EINVAL;
 299                 goto out;
 300         }
 301
 302         if (sc->hwp_pref_ctrl) {
 303                 val = percent_to_raw(val);
 304
 305                 sc->req =
 306                     ((sc->req & ~IA32_HWP_REQUEST_ENERGY_PERFORMANCE_PREFERENCE)
 307                     | (val << 24u));
 308
 309                 if (sc->hwp_pkg_ctrl_en)
 310                         ret = wrmsr_safe(MSR_IA32_HWP_REQUEST_PKG, sc->req);
 311                 else
 312                         ret = wrmsr_safe(MSR_IA32_HWP_REQUEST, sc->req);
 313         } else {
 314                 val = percent_to_raw_perf_bias(val);
 315                 MPASS((val & ~IA32_ENERGY_PERF_BIAS_POLICY_HINT_MASK) == 0);
 316
 317                 sc->hwp_energy_perf_bias =
 318                     ((sc->hwp_energy_perf_bias &
 319                     ~IA32_ENERGY_PERF_BIAS_POLICY_HINT_MASK) | val);
 320                 ret = wrmsr_safe(MSR_IA32_ENERGY_PERF_BIAS,
 321                     sc->hwp_energy_perf_bias);
 322         }
 323
 324 out:
 325         thread_lock(curthread);
 326         sched_unbind(curthread);
 327         thread_unlock(curthread);
 328
 329         return (ret);
 330 }
 331
 332 void
 333 intel_hwpstate_identify(driver_t *driver, device_t parent)
 334 {
 335         if (device_find_child(parent, "hwpstate_intel", -1) != NULL)
 336                 return;
 337
 338         if (cpu_vendor_id != CPU_VENDOR_INTEL)
 339                 return;
 340
 341         if (resource_disabled("hwpstate_intel", 0))
 342                 return;
 343
 344         /*
 345          * Intel SDM 14.4.1 (HWP Programming Interfaces):
 346          *   Availability of HWP baseline resource and capability,
 347          *   CPUID.06H:EAX[bit 7]: If this bit is set, HWP provides several new
 348          *   architectural MSRs: IA32_PM_ENABLE, IA32_HWP_CAPABILITIES,
 349          *   IA32_HWP_REQUEST, IA32_HWP_STATUS.
 350          */
 351         if ((cpu_power_eax & CPUTPM1_HWP) == 0)
 352                 return;
 353
 354         if (BUS_ADD_CHILD(parent, 10, "hwpstate_intel", -1) == NULL)
 355                 return;
 356
 357         if (bootverbose)
 358                 device_printf(parent, "hwpstate registered\n");
 359 }
 360
 361 static int
 362 intel_hwpstate_probe(device_t dev)
 363 {
 364
 365         device_set_desc(dev, "Intel Speed Shift");
 366         return (BUS_PROBE_NOWILDCARD);
 367 }
 368
 369 static int
 370 set_autonomous_hwp(struct hwp_softc *sc)
 371 {
 372         struct pcpu *pc;
 373         device_t dev;
 374         uint64_t caps;
 375         int ret;
 376
 377         dev = sc->dev;
 378
 379         pc = cpu_get_pcpu(dev);
 380         if (pc == NULL)
 381                 return (ENXIO);
 382
 383         thread_lock(curthread);
 384         sched_bind(curthread, pc->pc_cpuid);
 385         thread_unlock(curthread);
 386
 387         /* XXX: Many MSRs aren't readable until feature is enabled */
 388         ret = wrmsr_safe(MSR_IA32_PM_ENABLE, 1);
 389         if (ret) {
 390                 /*
 391                  * This is actually a package-level MSR, and only the first
 392                  * write is not ignored.  So it is harmless to enable it across
 393                  * all devices, and this allows us not to care especially in
 394                  * which order cores (and packages) are probed.  This error
 395                  * condition should not happen given we gate on the HWP CPUID
 396                  * feature flag, if the Intel SDM is correct.
 397                  */
 398                 device_printf(dev, "Failed to enable HWP for cpu%d (%d)\n",
 399                     pc->pc_cpuid, ret);
 400                 goto out;
 401         }
 402
 403         ret = rdmsr_safe(MSR_IA32_HWP_REQUEST, &sc->req);
 404         if (ret) {
 405                 device_printf(dev,
 406                     "Failed to read HWP request MSR for cpu%d (%d)\n",
 407                     pc->pc_cpuid, ret);
 408                 goto out;
 409         }
 410
 411         ret = rdmsr_safe(MSR_IA32_HWP_CAPABILITIES, &caps);
 412         if (ret) {
 413                 device_printf(dev,
 414                     "Failed to read HWP capabilities MSR for cpu%d (%d)\n",
 415                     pc->pc_cpuid, ret);
 416                 goto out;
 417         }
 418
 419         /*
 420          * High and low are static; "guaranteed" is dynamic; and efficient is
 421          * also dynamic.
 422          */
 423         sc->high = IA32_HWP_CAPABILITIES_HIGHEST_PERFORMANCE(caps);
 424         sc->guaranteed = IA32_HWP_CAPABILITIES_GUARANTEED_PERFORMANCE(caps);
 425         sc->efficient = IA32_HWP_CAPABILITIES_EFFICIENT_PERFORMANCE(caps);
 426         sc->low = IA32_HWP_CAPABILITIES_LOWEST_PERFORMANCE(caps);
 427
 428         /* hardware autonomous selection determines the performance target */
 429         sc->req &= ~IA32_HWP_DESIRED_PERFORMANCE;
 430
 431         /* enable HW dynamic selection of window size */
 432         sc->req &= ~IA32_HWP_ACTIVITY_WINDOW;
 433
 434         /* IA32_HWP_REQUEST.Minimum_Performance = IA32_HWP_CAPABILITIES.Lowest_Performance */
 435         sc->req &= ~IA32_HWP_MINIMUM_PERFORMANCE;
 436         sc->req |= sc->low;
 437
 438         /* IA32_HWP_REQUEST.Maximum_Performance = IA32_HWP_CAPABILITIES.Highest_Performance. */
 439         sc->req &= ~IA32_HWP_REQUEST_MAXIMUM_PERFORMANCE;
 440         sc->req |= sc->high << 8;
 441
 442         /* If supported, request package-level control for this CPU. */
 443         if (sc->hwp_pkg_ctrl_en)
 444                 ret = wrmsr_safe(MSR_IA32_HWP_REQUEST, sc->req |
 445                     IA32_HWP_REQUEST_PACKAGE_CONTROL);
 446         else
 447                 ret = wrmsr_safe(MSR_IA32_HWP_REQUEST, sc->req);
 448         if (ret) {
 449                 device_printf(dev,
 450                     "Failed to setup%s autonomous HWP for cpu%d\n",
 451                     sc->hwp_pkg_ctrl_en ? " PKG" : "", pc->pc_cpuid);
 452                 goto out;
 453         }
 454
 455         /* If supported, write the PKG-wide control MSR. */
 456         if (sc->hwp_pkg_ctrl_en) {
 457                 /*
 458                  * "The structure of the IA32_HWP_REQUEST_PKG MSR
 459                  * (package-level) is identical to the IA32_HWP_REQUEST MSR
 460                  * with the exception of the Package Control field, which does
 461                  * not exist." (Intel SDM §14.4.4)
 462                  */
 463                 ret = wrmsr_safe(MSR_IA32_HWP_REQUEST_PKG, sc->req);
 464                 device_printf(dev,
 465                     "Failed to set autonomous HWP for package\n");
 466         }
 467
 468 out:
 469         thread_lock(curthread);
 470         sched_unbind(curthread);
 471         thread_unlock(curthread);
 472
 473         return (ret);
 474 }
 475
 476 static int
 477 intel_hwpstate_attach(device_t dev)
 478 {
 479         struct hwp_softc *sc;
 480         int ret;
 481
 482         sc = device_get_softc(dev);
 483         sc->dev = dev;
 484
 485         /* eax */
 486         if (cpu_power_eax & CPUTPM1_HWP_NOTIFICATION)
 487                 sc->hwp_notifications = true;
 488         if (cpu_power_eax & CPUTPM1_HWP_ACTIVITY_WINDOW)
 489                 sc->hwp_activity_window = true;
 490         if (cpu_power_eax & CPUTPM1_HWP_PERF_PREF)
 491                 sc->hwp_pref_ctrl = true;
 492         if (cpu_power_eax & CPUTPM1_HWP_PKG)
 493                 sc->hwp_pkg_ctrl = true;
 494
 495         /* Allow administrators to disable pkg-level control. */
 496         sc->hwp_pkg_ctrl_en = (sc->hwp_pkg_ctrl && hwpstate_pkg_ctrl_enable);
 497
 498         /* ecx */
 499         if (cpu_power_ecx & CPUID_PERF_BIAS)
 500                 sc->hwp_perf_bias = true;
 501
 502         ret = set_autonomous_hwp(sc);
 503         if (ret)
 504                 return (ret);
 505
 506         SYSCTL_ADD_PROC(device_get_sysctl_ctx(dev),
 507             SYSCTL_STATIC_CHILDREN(_debug), OID_AUTO, device_get_nameunit(dev),
 508             CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_SKIP | CTLFLAG_NEEDGIANT,
 509             sc, 0, intel_hwp_dump_sysctl_handler, "A", "");
 510
 511         SYSCTL_ADD_PROC(device_get_sysctl_ctx(dev),
 512             SYSCTL_CHILDREN(device_get_sysctl_tree(dev)), OID_AUTO,
 513             "epp", CTLTYPE_INT | CTLFLAG_RWTUN | CTLFLAG_NEEDGIANT, dev, 0,
 514             sysctl_epp_select, "I",
 515             "Efficiency/Performance Preference "
 516             "(range from 0, most performant, through 100, most efficient)");
 517
 518         return (cpufreq_register(dev));
 519 }
 520
 521 static int
 522 intel_hwpstate_detach(device_t dev)
 523 {
 524
 525         return (cpufreq_unregister(dev));
 526 }
 527
 528 static int
 529 intel_hwpstate_get(device_t dev, struct cf_setting *set)
 530 {
 531         struct pcpu *pc;
 532         uint64_t rate;
 533         int ret;
 534
 535         if (set == NULL)
 536                 return (EINVAL);
 537
 538         pc = cpu_get_pcpu(dev);
 539         if (pc == NULL)
 540                 return (ENXIO);
 541
 542         memset(set, CPUFREQ_VAL_UNKNOWN, sizeof(*set));
 543         set->dev = dev;
 544
 545         ret = cpu_est_clockrate(pc->pc_cpuid, &rate);
 546         if (ret == 0)
 547                 set->freq = rate / 1000000;
 548
 549         set->volts = CPUFREQ_VAL_UNKNOWN;
 550         set->power = CPUFREQ_VAL_UNKNOWN;
 551         set->lat = CPUFREQ_VAL_UNKNOWN;
 552
 553         return (0);
 554 }
 555
 556 static int
 557 intel_hwpstate_type(device_t dev, int *type)
 558 {
 559         if (type == NULL)
 560                 return (EINVAL);
 561         *type = CPUFREQ_TYPE_ABSOLUTE | CPUFREQ_FLAG_INFO_ONLY | CPUFREQ_FLAG_UNCACHED;
 562
 563         return (0);
 564 }
 565
 566 static int
 567 intel_hwpstate_suspend(device_t dev)
 568 {
 569         return (0);
 570 }
 571
 572 /*
 573  * Redo a subset of set_autonomous_hwp on resume; untested.  Without this,
 574  * testers observed that on resume MSR_IA32_HWP_REQUEST was bogus.
 575  */
 576 static int
 577 intel_hwpstate_resume(device_t dev)
 578 {
 579         struct hwp_softc *sc;
 580         struct pcpu *pc;
 581         int ret;
 582
 583         sc = device_get_softc(dev);
 584
 585         pc = cpu_get_pcpu(dev);
 586         if (pc == NULL)
 587                 return (ENXIO);
 588
 589         thread_lock(curthread);
 590         sched_bind(curthread, pc->pc_cpuid);
 591         thread_unlock(curthread);
 592
 593         ret = wrmsr_safe(MSR_IA32_PM_ENABLE, 1);
 594         if (ret) {
 595                 device_printf(dev,
 596                     "Failed to enable HWP for cpu%d after suspend (%d)\n",
 597                     pc->pc_cpuid, ret);
 598                 goto out;
 599         }
 600
 601         if (sc->hwp_pkg_ctrl_en)
 602                 ret = wrmsr_safe(MSR_IA32_HWP_REQUEST, sc->req |
 603                     IA32_HWP_REQUEST_PACKAGE_CONTROL);
 604         else
 605                 ret = wrmsr_safe(MSR_IA32_HWP_REQUEST, sc->req);
 606         if (ret) {
 607                 device_printf(dev,
 608                     "Failed to set%s autonomous HWP for cpu%d after suspend\n",
 609                     sc->hwp_pkg_ctrl_en ? " PKG" : "", pc->pc_cpuid);
 610                 goto out;
 611         }
 612         if (sc->hwp_pkg_ctrl_en) {
 613                 ret = wrmsr_safe(MSR_IA32_HWP_REQUEST_PKG, sc->req);
 614                 if (ret) {
 615                         device_printf(dev,
 616                             "Failed to set autonomous HWP for package after "
 617                             "suspend\n");
 618                         goto out;
 619                 }
 620         }
 621         if (!sc->hwp_pref_ctrl && sc->hwp_perf_bias_cached) {
 622                 ret = wrmsr_safe(MSR_IA32_ENERGY_PERF_BIAS,
 623                     sc->hwp_energy_perf_bias);
 624                 if (ret) {
 625                         device_printf(dev,
 626                             "Failed to set energy perf bias for cpu%d after "
 627                             "suspend\n", pc->pc_cpuid);
 628                 }
 629         }
 630
 631 out:
 632         thread_lock(curthread);
 633         sched_unbind(curthread);
 634         thread_unlock(curthread);
 635
 636         return (ret);
 637 }