drivers/cpufreq/intel_pstate.c

   1 /*
   2  * intel_pstate.c: Native P state management for Intel processors
   3  *
   4  * (C) Copyright 2012 Intel Corporation
   5  * Author: Dirk Brandewie <dirk.j.brandewie@intel.com>
   6  *
   7  * This program is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU General Public License
   9  * as published by the Free Software Foundation; version 2
  10  * of the License.
  11  */
  12
  13 #include <linux/kernel.h>
  14 #include <linux/kernel_stat.h>
  15 #include <linux/module.h>
  16 #include <linux/ktime.h>
  17 #include <linux/hrtimer.h>
  18 #include <linux/tick.h>
  19 #include <linux/slab.h>
  20 #include <linux/sched.h>
  21 #include <linux/list.h>
  22 #include <linux/cpu.h>
  23 #include <linux/cpufreq.h>
  24 #include <linux/sysfs.h>
  25 #include <linux/types.h>
  26 #include <linux/fs.h>
  27 #include <linux/debugfs.h>
  28 #include <linux/acpi.h>
  29 #include <trace/events/power.h>
  30
  31 #include <asm/div64.h>
  32 #include <asm/msr.h>
  33 #include <asm/cpu_device_id.h>
  34
  35 #define BYT_RATIOS              0x66a
  36 #define BYT_VIDS                0x66b
  37 #define BYT_TURBO_RATIOS        0x66c
  38 #define BYT_TURBO_VIDS          0x66d
  39
  40 #define FRAC_BITS 8
  41 #define int_tofp(X) ((int64_t)(X) << FRAC_BITS)
  42 #define fp_toint(X) ((X) >> FRAC_BITS)
  43
  44
  45 static inline int32_t mul_fp(int32_t x, int32_t y)
  46 {
  47         return ((int64_t)x * (int64_t)y) >> FRAC_BITS;
  48 }
  49
  50 static inline int32_t div_fp(int32_t x, int32_t y)
  51 {
  52         return div_s64((int64_t)x << FRAC_BITS, y);
  53 }
  54
  55 struct sample {
  56         int32_t core_pct_busy;
  57         u64 aperf;
  58         u64 mperf;
  59         int freq;
  60         ktime_t time;
  61 };
  62
  63 struct pstate_data {
  64         int     current_pstate;
  65         int     min_pstate;
  66         int     max_pstate;
  67         int     turbo_pstate;
  68 };
  69
  70 struct vid_data {
  71         int min;
  72         int max;
  73         int turbo;
  74         int32_t ratio;
  75 };
  76
  77 struct _pid {
  78         int setpoint;
  79         int32_t integral;
  80         int32_t p_gain;
  81         int32_t i_gain;
  82         int32_t d_gain;
  83         int deadband;
  84         int32_t last_err;
  85 };
  86
  87 struct cpudata {
  88         int cpu;
  89
  90         struct timer_list timer;
  91
  92         struct pstate_data pstate;
  93         struct vid_data vid;
  94         struct _pid pid;
  95
  96         ktime_t last_sample_time;
  97         u64     prev_aperf;
  98         u64     prev_mperf;
  99         struct sample sample;
 100 };
 101
 102 static struct cpudata **all_cpu_data;
 103 struct pstate_adjust_policy {
 104         int sample_rate_ms;
 105         int deadband;
 106         int setpoint;
 107         int p_gain_pct;
 108         int d_gain_pct;
 109         int i_gain_pct;
 110 };
 111
 112 struct pstate_funcs {
 113         int (*get_max)(void);
 114         int (*get_min)(void);
 115         int (*get_turbo)(void);
 116         void (*set)(struct cpudata*, int pstate);
 117         void (*get_vid)(struct cpudata *);
 118 };
 119
 120 struct cpu_defaults {
 121         struct pstate_adjust_policy pid_policy;
 122         struct pstate_funcs funcs;
 123 };
 124
 125 static struct pstate_adjust_policy pid_params;
 126 static struct pstate_funcs pstate_funcs;
 127
 128 struct perf_limits {
 129         int no_turbo;
 130         int turbo_disabled;
 131         int max_perf_pct;
 132         int min_perf_pct;
 133         int32_t max_perf;
 134         int32_t min_perf;
 135         int max_policy_pct;
 136         int max_sysfs_pct;
 137 };
 138
 139 static struct perf_limits limits = {
 140         .no_turbo = 0,
 141         .max_perf_pct = 100,
 142         .max_perf = int_tofp(1),
 143         .min_perf_pct = 0,
 144         .min_perf = 0,
 145         .max_policy_pct = 100,
 146         .max_sysfs_pct = 100,
 147 };
 148
 149 static inline void pid_reset(struct _pid *pid, int setpoint, int busy,
 150                              int deadband, int integral) {
 151         pid->setpoint = setpoint;
 152         pid->deadband  = deadband;
 153         pid->integral  = int_tofp(integral);
 154         pid->last_err  = int_tofp(setpoint) - int_tofp(busy);
 155 }
 156
 157 static inline void pid_p_gain_set(struct _pid *pid, int percent)
 158 {
 159         pid->p_gain = div_fp(int_tofp(percent), int_tofp(100));
 160 }
 161
 162 static inline void pid_i_gain_set(struct _pid *pid, int percent)
 163 {
 164         pid->i_gain = div_fp(int_tofp(percent), int_tofp(100));
 165 }
 166
 167 static inline void pid_d_gain_set(struct _pid *pid, int percent)
 168 {
 169         pid->d_gain = div_fp(int_tofp(percent), int_tofp(100));
 170 }
 171
 172 static signed int pid_calc(struct _pid *pid, int32_t busy)
 173 {
 174         signed int result;
 175         int32_t pterm, dterm, fp_error;
 176         int32_t integral_limit;
 177
 178         fp_error = int_tofp(pid->setpoint) - busy;
 179
 180         if (abs(fp_error) <= int_tofp(pid->deadband))
 181                 return 0;
 182
 183         pterm = mul_fp(pid->p_gain, fp_error);
 184
 185         pid->integral += fp_error;
 186
 187         /* limit the integral term */
 188         integral_limit = int_tofp(30);
 189         if (pid->integral > integral_limit)
 190                 pid->integral = integral_limit;
 191         if (pid->integral < -integral_limit)
 192                 pid->integral = -integral_limit;
 193
 194         dterm = mul_fp(pid->d_gain, fp_error - pid->last_err);
 195         pid->last_err = fp_error;
 196
 197         result = pterm + mul_fp(pid->integral, pid->i_gain) + dterm;
 198         result = result + (1 << (FRAC_BITS-1));
 199         return (signed int)fp_toint(result);
 200 }
 201
 202 static inline void intel_pstate_busy_pid_reset(struct cpudata *cpu)
 203 {
 204         pid_p_gain_set(&cpu->pid, pid_params.p_gain_pct);
 205         pid_d_gain_set(&cpu->pid, pid_params.d_gain_pct);
 206         pid_i_gain_set(&cpu->pid, pid_params.i_gain_pct);
 207
 208         pid_reset(&cpu->pid, pid_params.setpoint, 100, pid_params.deadband, 0);
 209 }
 210
 211 static inline void intel_pstate_reset_all_pid(void)
 212 {
 213         unsigned int cpu;
 214
 215         for_each_online_cpu(cpu) {
 216                 if (all_cpu_data[cpu])
 217                         intel_pstate_busy_pid_reset(all_cpu_data[cpu]);
 218         }
 219 }
 220
 221 /************************** debugfs begin ************************/
 222 static int pid_param_set(void *data, u64 val)
 223 {
 224         *(u32 *)data = val;
 225         intel_pstate_reset_all_pid();
 226         return 0;
 227 }
 228
 229 static int pid_param_get(void *data, u64 *val)
 230 {
 231         *val = *(u32 *)data;
 232         return 0;
 233 }
 234 DEFINE_SIMPLE_ATTRIBUTE(fops_pid_param, pid_param_get, pid_param_set, "%llu\n");
 235
 236 struct pid_param {
 237         char *name;
 238         void *value;
 239 };
 240
 241 static struct pid_param pid_files[] = {
 242         {"sample_rate_ms", &pid_params.sample_rate_ms},
 243         {"d_gain_pct", &pid_params.d_gain_pct},
 244         {"i_gain_pct", &pid_params.i_gain_pct},
 245         {"deadband", &pid_params.deadband},
 246         {"setpoint", &pid_params.setpoint},
 247         {"p_gain_pct", &pid_params.p_gain_pct},
 248         {NULL, NULL}
 249 };
 250
 251 static void __init intel_pstate_debug_expose_params(void)
 252 {
 253         struct dentry *debugfs_parent;
 254         int i = 0;
 255
 256         debugfs_parent = debugfs_create_dir("pstate_snb", NULL);
 257         if (IS_ERR_OR_NULL(debugfs_parent))
 258                 return;
 259         while (pid_files[i].name) {
 260                 debugfs_create_file(pid_files[i].name, 0660,
 261                                     debugfs_parent, pid_files[i].value,
 262                                     &fops_pid_param);
 263                 i++;
 264         }
 265 }
 266
 267 /************************** debugfs end ************************/
 268
 269 /************************** sysfs begin ************************/
 270 #define show_one(file_name, object)                                     \
 271         static ssize_t show_##file_name                                 \
 272         (struct kobject *kobj, struct attribute *attr, char *buf)       \
 273         {                                                               \
 274                 return sprintf(buf, "%u\n", limits.object);             \
 275         }
 276
 277 static ssize_t store_no_turbo(struct kobject *a, struct attribute *b,
 278                               const char *buf, size_t count)
 279 {
 280         unsigned int input;
 281         int ret;
 282
 283         ret = sscanf(buf, "%u", &input);
 284         if (ret != 1)
 285                 return -EINVAL;
 286         limits.no_turbo = clamp_t(int, input, 0 , 1);
 287         if (limits.turbo_disabled) {
 288                 pr_warn("Turbo disabled by BIOS or unavailable on processor\n");
 289                 limits.no_turbo = limits.turbo_disabled;
 290         }
 291         return count;
 292 }
 293
 294 static ssize_t store_max_perf_pct(struct kobject *a, struct attribute *b,
 295                                   const char *buf, size_t count)
 296 {
 297         unsigned int input;
 298         int ret;
 299
 300         ret = sscanf(buf, "%u", &input);
 301         if (ret != 1)
 302                 return -EINVAL;
 303
 304         limits.max_sysfs_pct = clamp_t(int, input, 0 , 100);
 305         limits.max_perf_pct = min(limits.max_policy_pct, limits.max_sysfs_pct);
 306         limits.max_perf = div_fp(int_tofp(limits.max_perf_pct), int_tofp(100));
 307
 308         return count;
 309 }
 310
 311 static ssize_t store_min_perf_pct(struct kobject *a, struct attribute *b,
 312                                   const char *buf, size_t count)
 313 {
 314         unsigned int input;
 315         int ret;
 316
 317         ret = sscanf(buf, "%u", &input);
 318         if (ret != 1)
 319                 return -EINVAL;
 320         limits.min_perf_pct = clamp_t(int, input, 0 , 100);
 321         limits.min_perf = div_fp(int_tofp(limits.min_perf_pct), int_tofp(100));
 322
 323         return count;
 324 }
 325
 326 show_one(no_turbo, no_turbo);
 327 show_one(max_perf_pct, max_perf_pct);
 328 show_one(min_perf_pct, min_perf_pct);
 329
 330 define_one_global_rw(no_turbo);
 331 define_one_global_rw(max_perf_pct);
 332 define_one_global_rw(min_perf_pct);
 333
 334 static struct attribute *intel_pstate_attributes[] = {
 335         &no_turbo.attr,
 336         &max_perf_pct.attr,
 337         &min_perf_pct.attr,
 338         NULL
 339 };
 340
 341 static struct attribute_group intel_pstate_attr_group = {
 342         .attrs = intel_pstate_attributes,
 343 };
 344
 345 static void __init intel_pstate_sysfs_expose_params(void)
 346 {
 347         struct kobject *intel_pstate_kobject;
 348         int rc;
 349
 350         intel_pstate_kobject = kobject_create_and_add("intel_pstate",
 351                                                 &cpu_subsys.dev_root->kobj);
 352         BUG_ON(!intel_pstate_kobject);
 353         rc = sysfs_create_group(intel_pstate_kobject, &intel_pstate_attr_group);
 354         BUG_ON(rc);
 355 }
 356
 357 /************************** sysfs end ************************/
 358 static int byt_get_min_pstate(void)
 359 {
 360         u64 value;
 361
 362         rdmsrl(BYT_RATIOS, value);
 363         return (value >> 8) & 0x7F;
 364 }
 365
 366 static int byt_get_max_pstate(void)
 367 {
 368         u64 value;
 369
 370         rdmsrl(BYT_RATIOS, value);
 371         return (value >> 16) & 0x7F;
 372 }
 373
 374 static int byt_get_turbo_pstate(void)
 375 {
 376         u64 value;
 377
 378         rdmsrl(BYT_TURBO_RATIOS, value);
 379         return value & 0x7F;
 380 }
 381
 382 static void byt_set_pstate(struct cpudata *cpudata, int pstate)
 383 {
 384         u64 val;
 385         int32_t vid_fp;
 386         u32 vid;
 387
 388         val = pstate << 8;
 389         if (limits.no_turbo && !limits.turbo_disabled)
 390                 val |= (u64)1 << 32;
 391
 392         vid_fp = cpudata->vid.min + mul_fp(
 393                 int_tofp(pstate - cpudata->pstate.min_pstate),
 394                 cpudata->vid.ratio);
 395
 396         vid_fp = clamp_t(int32_t, vid_fp, cpudata->vid.min, cpudata->vid.max);
 397         vid = fp_toint(vid_fp);
 398
 399         if (pstate > cpudata->pstate.max_pstate)
 400                 vid = cpudata->vid.turbo;
 401
 402         val |= vid;
 403
 404         wrmsrl(MSR_IA32_PERF_CTL, val);
 405 }
 406
 407 static void byt_get_vid(struct cpudata *cpudata)
 408 {
 409         u64 value;
 410
 411         rdmsrl(BYT_VIDS, value);
 412         cpudata->vid.min = int_tofp((value >> 8) & 0x7f);
 413         cpudata->vid.max = int_tofp((value >> 16) & 0x7f);
 414         cpudata->vid.ratio = div_fp(
 415                 cpudata->vid.max - cpudata->vid.min,
 416                 int_tofp(cpudata->pstate.max_pstate -
 417                         cpudata->pstate.min_pstate));
 418
 419         rdmsrl(BYT_TURBO_VIDS, value);
 420         cpudata->vid.turbo = value & 0x7f;
 421 }
 422
 423 static int core_get_min_pstate(void)
 424 {
 425         u64 value;
 426
 427         rdmsrl(MSR_PLATFORM_INFO, value);
 428         return (value >> 40) & 0xFF;
 429 }
 430
 431 static int core_get_max_pstate(void)
 432 {
 433         u64 value;
 434
 435         rdmsrl(MSR_PLATFORM_INFO, value);
 436         return (value >> 8) & 0xFF;
 437 }
 438
 439 static int core_get_turbo_pstate(void)
 440 {
 441         u64 value;
 442         int nont, ret;
 443
 444         rdmsrl(MSR_NHM_TURBO_RATIO_LIMIT, value);
 445         nont = core_get_max_pstate();
 446         ret = (value) & 255;
 447         if (ret <= nont)
 448                 ret = nont;
 449         return ret;
 450 }
 451
 452 static void core_set_pstate(struct cpudata *cpudata, int pstate)
 453 {
 454         u64 val;
 455
 456         val = pstate << 8;
 457         if (limits.no_turbo && !limits.turbo_disabled)
 458                 val |= (u64)1 << 32;
 459
 460         wrmsrl_on_cpu(cpudata->cpu, MSR_IA32_PERF_CTL, val);
 461 }
 462
 463 static struct cpu_defaults core_params = {
 464         .pid_policy = {
 465                 .sample_rate_ms = 10,
 466                 .deadband = 0,
 467                 .setpoint = 97,
 468                 .p_gain_pct = 20,
 469                 .d_gain_pct = 0,
 470                 .i_gain_pct = 0,
 471         },
 472         .funcs = {
 473                 .get_max = core_get_max_pstate,
 474                 .get_min = core_get_min_pstate,
 475                 .get_turbo = core_get_turbo_pstate,
 476                 .set = core_set_pstate,
 477         },
 478 };
 479
 480 static struct cpu_defaults byt_params = {
 481         .pid_policy = {
 482                 .sample_rate_ms = 10,
 483                 .deadband = 0,
 484                 .setpoint = 97,
 485                 .p_gain_pct = 14,
 486                 .d_gain_pct = 0,
 487                 .i_gain_pct = 4,
 488         },
 489         .funcs = {
 490                 .get_max = byt_get_max_pstate,
 491                 .get_min = byt_get_min_pstate,
 492                 .get_turbo = byt_get_turbo_pstate,
 493                 .set = byt_set_pstate,
 494                 .get_vid = byt_get_vid,
 495         },
 496 };
 497
 498 static void intel_pstate_get_min_max(struct cpudata *cpu, int *min, int *max)
 499 {
 500         int max_perf = cpu->pstate.turbo_pstate;
 501         int max_perf_adj;
 502         int min_perf;
 503
 504         if (limits.no_turbo)
 505                 max_perf = cpu->pstate.max_pstate;
 506
 507         max_perf_adj = fp_toint(mul_fp(int_tofp(max_perf), limits.max_perf));
 508         *max = clamp_t(int, max_perf_adj,
 509                         cpu->pstate.min_pstate, cpu->pstate.turbo_pstate);
 510
 511         min_perf = fp_toint(mul_fp(int_tofp(max_perf), limits.min_perf));
 512         *min = clamp_t(int, min_perf, cpu->pstate.min_pstate, max_perf);
 513 }
 514
 515 static void intel_pstate_set_pstate(struct cpudata *cpu, int pstate)
 516 {
 517         int max_perf, min_perf;
 518
 519         intel_pstate_get_min_max(cpu, &min_perf, &max_perf);
 520
 521         pstate = clamp_t(int, pstate, min_perf, max_perf);
 522
 523         if (pstate == cpu->pstate.current_pstate)
 524                 return;
 525
 526         trace_cpu_frequency(pstate * 100000, cpu->cpu);
 527
 528         cpu->pstate.current_pstate = pstate;
 529
 530         pstate_funcs.set(cpu, pstate);
 531 }
 532
 533 static void intel_pstate_get_cpu_pstates(struct cpudata *cpu)
 534 {
 535         cpu->pstate.min_pstate = pstate_funcs.get_min();
 536         cpu->pstate.max_pstate = pstate_funcs.get_max();
 537         cpu->pstate.turbo_pstate = pstate_funcs.get_turbo();
 538
 539         if (pstate_funcs.get_vid)
 540                 pstate_funcs.get_vid(cpu);
 541         intel_pstate_set_pstate(cpu, cpu->pstate.min_pstate);
 542 }
 543
 544 static inline void intel_pstate_calc_busy(struct cpudata *cpu)
 545 {
 546         struct sample *sample = &cpu->sample;
 547         int64_t core_pct;
 548
 549         core_pct = int_tofp(sample->aperf) * int_tofp(100);
 550         core_pct = div64_u64(core_pct, int_tofp(sample->mperf));
 551
 552         sample->freq = fp_toint(
 553                 mul_fp(int_tofp(cpu->pstate.max_pstate * 1000), core_pct));
 554
 555         sample->core_pct_busy = (int32_t)core_pct;
 556 }
 557
 558 static inline void intel_pstate_sample(struct cpudata *cpu)
 559 {
 560         u64 aperf, mperf;
 561         unsigned long flags;
 562
 563         local_irq_save(flags);
 564         rdmsrl(MSR_IA32_APERF, aperf);
 565         rdmsrl(MSR_IA32_MPERF, mperf);
 566         local_irq_restore(flags);
 567
 568         cpu->last_sample_time = cpu->sample.time;
 569         cpu->sample.time = ktime_get();
 570         cpu->sample.aperf = aperf;
 571         cpu->sample.mperf = mperf;
 572         cpu->sample.aperf -= cpu->prev_aperf;
 573         cpu->sample.mperf -= cpu->prev_mperf;
 574
 575         intel_pstate_calc_busy(cpu);
 576
 577         cpu->prev_aperf = aperf;
 578         cpu->prev_mperf = mperf;
 579 }
 580
 581 static inline void intel_pstate_set_sample_time(struct cpudata *cpu)
 582 {
 583         int delay;
 584
 585         delay = msecs_to_jiffies(pid_params.sample_rate_ms);
 586         mod_timer_pinned(&cpu->timer, jiffies + delay);
 587 }
 588
 589 static inline int32_t intel_pstate_get_scaled_busy(struct cpudata *cpu)
 590 {
 591         int32_t core_busy, max_pstate, current_pstate, sample_ratio;
 592         u32 duration_us;
 593         u32 sample_time;
 594
 595         core_busy = cpu->sample.core_pct_busy;
 596         max_pstate = int_tofp(cpu->pstate.max_pstate);
 597         current_pstate = int_tofp(cpu->pstate.current_pstate);
 598         core_busy = mul_fp(core_busy, div_fp(max_pstate, current_pstate));
 599
 600         sample_time = pid_params.sample_rate_ms  * USEC_PER_MSEC;
 601         duration_us = (u32) ktime_us_delta(cpu->sample.time,
 602                                            cpu->last_sample_time);
 603         if (duration_us > sample_time * 3) {
 604                 sample_ratio = div_fp(int_tofp(sample_time),
 605                                       int_tofp(duration_us));
 606                 core_busy = mul_fp(core_busy, sample_ratio);
 607         }
 608
 609         return core_busy;
 610 }
 611
 612 static inline void intel_pstate_adjust_busy_pstate(struct cpudata *cpu)
 613 {
 614         int32_t busy_scaled;
 615         struct _pid *pid;
 616         signed int ctl;
 617
 618         pid = &cpu->pid;
 619         busy_scaled = intel_pstate_get_scaled_busy(cpu);
 620
 621         ctl = pid_calc(pid, busy_scaled);
 622
 623         /* Negative values of ctl increase the pstate and vice versa */
 624         intel_pstate_set_pstate(cpu, cpu->pstate.current_pstate - ctl);
 625 }
 626
 627 static void intel_pstate_timer_func(unsigned long __data)
 628 {
 629         struct cpudata *cpu = (struct cpudata *) __data;
 630         struct sample *sample;
 631
 632         intel_pstate_sample(cpu);
 633
 634         sample = &cpu->sample;
 635
 636         intel_pstate_adjust_busy_pstate(cpu);
 637
 638         trace_pstate_sample(fp_toint(sample->core_pct_busy),
 639                         fp_toint(intel_pstate_get_scaled_busy(cpu)),
 640                         cpu->pstate.current_pstate,
 641                         sample->mperf,
 642                         sample->aperf,
 643                         sample->freq);
 644
 645         intel_pstate_set_sample_time(cpu);
 646 }
 647
 648 #define ICPU(model, policy) \
 649         { X86_VENDOR_INTEL, 6, model, X86_FEATURE_APERFMPERF,\
 650                         (unsigned long)&policy }
 651
 652 static const struct x86_cpu_id intel_pstate_cpu_ids[] = {
 653         ICPU(0x2a, core_params),
 654         ICPU(0x2d, core_params),
 655         ICPU(0x37, byt_params),
 656         ICPU(0x3a, core_params),
 657         ICPU(0x3c, core_params),
 658         ICPU(0x3d, core_params),
 659         ICPU(0x3e, core_params),
 660         ICPU(0x3f, core_params),
 661         ICPU(0x45, core_params),
 662         ICPU(0x46, core_params),
 663         ICPU(0x4f, core_params),
 664         ICPU(0x56, core_params),
 665         {}
 666 };
 667 MODULE_DEVICE_TABLE(x86cpu, intel_pstate_cpu_ids);
 668
 669 static int intel_pstate_init_cpu(unsigned int cpunum)
 670 {
 671         struct cpudata *cpu;
 672
 673         all_cpu_data[cpunum] = kzalloc(sizeof(struct cpudata), GFP_KERNEL);
 674         if (!all_cpu_data[cpunum])
 675                 return -ENOMEM;
 676
 677         cpu = all_cpu_data[cpunum];
 678
 679         cpu->cpu = cpunum;
 680         intel_pstate_get_cpu_pstates(cpu);
 681
 682         init_timer_deferrable(&cpu->timer);
 683         cpu->timer.function = intel_pstate_timer_func;
 684         cpu->timer.data = (unsigned long)cpu;
 685         cpu->timer.expires = jiffies + HZ/100;
 686         intel_pstate_busy_pid_reset(cpu);
 687         intel_pstate_sample(cpu);
 688
 689         add_timer_on(&cpu->timer, cpunum);
 690
 691         pr_info("Intel pstate controlling: cpu %d\n", cpunum);
 692
 693         return 0;
 694 }
 695
 696 static unsigned int intel_pstate_get(unsigned int cpu_num)
 697 {
 698         struct sample *sample;
 699         struct cpudata *cpu;
 700
 701         cpu = all_cpu_data[cpu_num];
 702         if (!cpu)
 703                 return 0;
 704         sample = &cpu->sample;
 705         return sample->freq;
 706 }
 707
 708 static int intel_pstate_set_policy(struct cpufreq_policy *policy)
 709 {
 710         struct cpudata *cpu;
 711
 712         cpu = all_cpu_data[policy->cpu];
 713
 714         if (!policy->cpuinfo.max_freq)
 715                 return -ENODEV;
 716
 717         if (policy->policy == CPUFREQ_POLICY_PERFORMANCE) {
 718                 limits.min_perf_pct = 100;
 719                 limits.min_perf = int_tofp(1);
 720                 limits.max_perf_pct = 100;
 721                 limits.max_perf = int_tofp(1);
 722                 limits.no_turbo = limits.turbo_disabled;
 723                 return 0;
 724         }
 725         limits.min_perf_pct = (policy->min * 100) / policy->cpuinfo.max_freq;
 726         limits.min_perf_pct = clamp_t(int, limits.min_perf_pct, 0 , 100);
 727         limits.min_perf = div_fp(int_tofp(limits.min_perf_pct), int_tofp(100));
 728
 729         limits.max_policy_pct = (policy->max * 100) / policy->cpuinfo.max_freq;
 730         limits.max_policy_pct = clamp_t(int, limits.max_policy_pct, 0 , 100);
 731         limits.max_perf_pct = min(limits.max_policy_pct, limits.max_sysfs_pct);
 732         limits.max_perf = div_fp(int_tofp(limits.max_perf_pct), int_tofp(100));
 733
 734         return 0;
 735 }
 736
 737 static int intel_pstate_verify_policy(struct cpufreq_policy *policy)
 738 {
 739         cpufreq_verify_within_cpu_limits(policy);
 740
 741         if (policy->policy != CPUFREQ_POLICY_POWERSAVE &&
 742             policy->policy != CPUFREQ_POLICY_PERFORMANCE)
 743                 return -EINVAL;
 744
 745         return 0;
 746 }
 747
 748 static void intel_pstate_stop_cpu(struct cpufreq_policy *policy)
 749 {
 750         int cpu_num = policy->cpu;
 751         struct cpudata *cpu = all_cpu_data[cpu_num];
 752
 753         pr_info("intel_pstate CPU %d exiting\n", cpu_num);
 754
 755         del_timer_sync(&all_cpu_data[cpu_num]->timer);
 756         intel_pstate_set_pstate(cpu, cpu->pstate.min_pstate);
 757         kfree(all_cpu_data[cpu_num]);
 758         all_cpu_data[cpu_num] = NULL;
 759 }
 760
 761 static int intel_pstate_cpu_init(struct cpufreq_policy *policy)
 762 {
 763         struct cpudata *cpu;
 764         int rc;
 765         u64 misc_en;
 766
 767         rc = intel_pstate_init_cpu(policy->cpu);
 768         if (rc)
 769                 return rc;
 770
 771         cpu = all_cpu_data[policy->cpu];
 772
 773         rdmsrl(MSR_IA32_MISC_ENABLE, misc_en);
 774         if (misc_en & MSR_IA32_MISC_ENABLE_TURBO_DISABLE ||
 775             cpu->pstate.max_pstate == cpu->pstate.turbo_pstate) {
 776                 limits.turbo_disabled = 1;
 777                 limits.no_turbo = 1;
 778         }
 779         if (limits.min_perf_pct == 100 && limits.max_perf_pct == 100)
 780                 policy->policy = CPUFREQ_POLICY_PERFORMANCE;
 781         else
 782                 policy->policy = CPUFREQ_POLICY_POWERSAVE;
 783
 784         policy->min = cpu->pstate.min_pstate * 100000;
 785         policy->max = cpu->pstate.turbo_pstate * 100000;
 786
 787         /* cpuinfo and default policy values */
 788         policy->cpuinfo.min_freq = cpu->pstate.min_pstate * 100000;
 789         policy->cpuinfo.max_freq = cpu->pstate.turbo_pstate * 100000;
 790         policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
 791         cpumask_set_cpu(policy->cpu, policy->cpus);
 792
 793         return 0;
 794 }
 795
 796 static struct cpufreq_driver intel_pstate_driver = {
 797         .flags          = CPUFREQ_CONST_LOOPS,
 798         .verify         = intel_pstate_verify_policy,
 799         .setpolicy      = intel_pstate_set_policy,
 800         .get            = intel_pstate_get,
 801         .init           = intel_pstate_cpu_init,
 802         .stop_cpu       = intel_pstate_stop_cpu,
 803         .name           = "intel_pstate",
 804 };
 805
 806 static int __initdata no_load;
 807
 808 static int intel_pstate_msrs_not_valid(void)
 809 {
 810         /* Check that all the msr's we are using are valid. */
 811         u64 aperf, mperf, tmp;
 812
 813         rdmsrl(MSR_IA32_APERF, aperf);
 814         rdmsrl(MSR_IA32_MPERF, mperf);
 815
 816         if (!pstate_funcs.get_max() ||
 817             !pstate_funcs.get_min() ||
 818             !pstate_funcs.get_turbo())
 819                 return -ENODEV;
 820
 821         rdmsrl(MSR_IA32_APERF, tmp);
 822         if (!(tmp - aperf))
 823                 return -ENODEV;
 824
 825         rdmsrl(MSR_IA32_MPERF, tmp);
 826         if (!(tmp - mperf))
 827                 return -ENODEV;
 828
 829         return 0;
 830 }
 831
 832 static void copy_pid_params(struct pstate_adjust_policy *policy)
 833 {
 834         pid_params.sample_rate_ms = policy->sample_rate_ms;
 835         pid_params.p_gain_pct = policy->p_gain_pct;
 836         pid_params.i_gain_pct = policy->i_gain_pct;
 837         pid_params.d_gain_pct = policy->d_gain_pct;
 838         pid_params.deadband = policy->deadband;
 839         pid_params.setpoint = policy->setpoint;
 840 }
 841
 842 static void copy_cpu_funcs(struct pstate_funcs *funcs)
 843 {
 844         pstate_funcs.get_max   = funcs->get_max;
 845         pstate_funcs.get_min   = funcs->get_min;
 846         pstate_funcs.get_turbo = funcs->get_turbo;
 847         pstate_funcs.set       = funcs->set;
 848         pstate_funcs.get_vid   = funcs->get_vid;
 849 }
 850
 851 #if IS_ENABLED(CONFIG_ACPI)
 852 #include <acpi/processor.h>
 853
 854 static bool intel_pstate_no_acpi_pss(void)
 855 {
 856         int i;
 857
 858         for_each_possible_cpu(i) {
 859                 acpi_status status;
 860                 union acpi_object *pss;
 861                 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 862                 struct acpi_processor *pr = per_cpu(processors, i);
 863
 864                 if (!pr)
 865                         continue;
 866
 867                 status = acpi_evaluate_object(pr->handle, "_PSS", NULL, &buffer);
 868                 if (ACPI_FAILURE(status))
 869                         continue;
 870
 871                 pss = buffer.pointer;
 872                 if (pss && pss->type == ACPI_TYPE_PACKAGE) {
 873                         kfree(pss);
 874                         return false;
 875                 }
 876
 877                 kfree(pss);
 878         }
 879
 880         return true;
 881 }
 882
 883 struct hw_vendor_info {
 884         u16  valid;
 885         char oem_id[ACPI_OEM_ID_SIZE];
 886         char oem_table_id[ACPI_OEM_TABLE_ID_SIZE];
 887 };
 888
 889 /* Hardware vendor-specific info that has its own power management modes */
 890 static struct hw_vendor_info vendor_info[] = {
 891         {1, "HP    ", "ProLiant"},
 892         {0, "", ""},
 893 };
 894
 895 static bool intel_pstate_platform_pwr_mgmt_exists(void)
 896 {
 897         struct acpi_table_header hdr;
 898         struct hw_vendor_info *v_info;
 899
 900         if (acpi_disabled ||
 901             ACPI_FAILURE(acpi_get_table_header(ACPI_SIG_FADT, 0, &hdr)))
 902                 return false;
 903
 904         for (v_info = vendor_info; v_info->valid; v_info++) {
 905                 if (!strncmp(hdr.oem_id, v_info->oem_id, ACPI_OEM_ID_SIZE) &&
 906                     !strncmp(hdr.oem_table_id, v_info->oem_table_id, ACPI_OEM_TABLE_ID_SIZE) &&
 907                     intel_pstate_no_acpi_pss())
 908                         return true;
 909         }
 910
 911         return false;
 912 }
 913 #else /* CONFIG_ACPI not enabled */
 914 static inline bool intel_pstate_platform_pwr_mgmt_exists(void) { return false; }
 915 #endif /* CONFIG_ACPI */
 916
 917 static int __init intel_pstate_init(void)
 918 {
 919         int cpu, rc = 0;
 920         const struct x86_cpu_id *id;
 921         struct cpu_defaults *cpu_info;
 922
 923         if (no_load)
 924                 return -ENODEV;
 925
 926         id = x86_match_cpu(intel_pstate_cpu_ids);
 927         if (!id)
 928                 return -ENODEV;
 929
 930         /*
 931          * The Intel pstate driver will be ignored if the platform
 932          * firmware has its own power management modes.
 933          */
 934         if (intel_pstate_platform_pwr_mgmt_exists())
 935                 return -ENODEV;
 936
 937         cpu_info = (struct cpu_defaults *)id->driver_data;
 938
 939         copy_pid_params(&cpu_info->pid_policy);
 940         copy_cpu_funcs(&cpu_info->funcs);
 941
 942         if (intel_pstate_msrs_not_valid())
 943                 return -ENODEV;
 944
 945         pr_info("Intel P-state driver initializing.\n");
 946
 947         all_cpu_data = vzalloc(sizeof(void *) * num_possible_cpus());
 948         if (!all_cpu_data)
 949                 return -ENOMEM;
 950
 951         rc = cpufreq_register_driver(&intel_pstate_driver);
 952         if (rc)
 953                 goto out;
 954
 955         intel_pstate_debug_expose_params();
 956         intel_pstate_sysfs_expose_params();
 957
 958         return rc;
 959 out:
 960         get_online_cpus();
 961         for_each_online_cpu(cpu) {
 962                 if (all_cpu_data[cpu]) {
 963                         del_timer_sync(&all_cpu_data[cpu]->timer);
 964                         kfree(all_cpu_data[cpu]);
 965                 }
 966         }
 967
 968         put_online_cpus();
 969         vfree(all_cpu_data);
 970         return -ENODEV;
 971 }
 972 device_initcall(intel_pstate_init);
 973
 974 static int __init intel_pstate_setup(char *str)
 975 {
 976         if (!str)
 977                 return -EINVAL;
 978
 979         if (!strcmp(str, "disable"))
 980                 no_load = 1;
 981         return 0;
 982 }
 983 early_param("intel_pstate", intel_pstate_setup);
 984
 985 MODULE_AUTHOR("Dirk Brandewie <dirk.j.brandewie@intel.com>");
 986 MODULE_DESCRIPTION("'intel_pstate' - P state driver Intel Core processors");
 987 MODULE_LICENSE("GPL");