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 SAMPLE_COUNT            3
  36
  37 #define BYT_RATIOS              0x66a
  38 #define BYT_VIDS                0x66b
  39 #define BYT_TURBO_RATIOS        0x66c
  40
  41
  42 #define FRAC_BITS 8
  43 #define int_tofp(X) ((int64_t)(X) << FRAC_BITS)
  44 #define fp_toint(X) ((X) >> FRAC_BITS)
  45
  46 static inline int32_t mul_fp(int32_t x, int32_t y)
  47 {
  48         return ((int64_t)x * (int64_t)y) >> FRAC_BITS;
  49 }
  50
  51 static inline int32_t div_fp(int32_t x, int32_t y)
  52 {
  53         return div_s64((int64_t)x << FRAC_BITS, (int64_t)y);
  54 }
  55
  56 struct sample {
  57         int32_t core_pct_busy;
  58         u64 aperf;
  59         u64 mperf;
  60         unsigned long long tsc;
  61         int freq;
  62 };
  63
  64 struct pstate_data {
  65         int     current_pstate;
  66         int     min_pstate;
  67         int     max_pstate;
  68         int     turbo_pstate;
  69 };
  70
  71 struct vid_data {
  72         int32_t min;
  73         int32_t max;
  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         char name[64];
  91
  92         struct timer_list timer;
  93
  94         struct pstate_data pstate;
  95         struct vid_data vid;
  96         struct _pid pid;
  97
  98         u64     prev_aperf;
  99         u64     prev_mperf;
 100         unsigned long long prev_tsc;
 101         int     sample_ptr;
 102         struct sample samples[SAMPLE_COUNT];
 103 };
 104
 105 static struct cpudata **all_cpu_data;
 106 struct pstate_adjust_policy {
 107         int sample_rate_ms;
 108         int deadband;
 109         int setpoint;
 110         int p_gain_pct;
 111         int d_gain_pct;
 112         int i_gain_pct;
 113 };
 114
 115 struct pstate_funcs {
 116         int (*get_max)(void);
 117         int (*get_min)(void);
 118         int (*get_turbo)(void);
 119         void (*set)(struct cpudata*, int pstate);
 120         void (*get_vid)(struct cpudata *);
 121 };
 122
 123 struct cpu_defaults {
 124         struct pstate_adjust_policy pid_policy;
 125         struct pstate_funcs funcs;
 126 };
 127
 128 static struct pstate_adjust_policy pid_params;
 129 static struct pstate_funcs pstate_funcs;
 130
 131 struct perf_limits {
 132         int no_turbo;
 133         int max_perf_pct;
 134         int min_perf_pct;
 135         int32_t max_perf;
 136         int32_t min_perf;
 137         int max_policy_pct;
 138         int max_sysfs_pct;
 139 };
 140
 141 static struct perf_limits limits = {
 142         .no_turbo = 0,
 143         .max_perf_pct = 100,
 144         .max_perf = int_tofp(1),
 145         .min_perf_pct = 0,
 146         .min_perf = 0,
 147         .max_policy_pct = 100,
 148         .max_sysfs_pct = 100,
 149 };
 150
 151 static inline void pid_reset(struct _pid *pid, int setpoint, int busy,
 152                         int deadband, int integral) {
 153         pid->setpoint = setpoint;
 154         pid->deadband  = deadband;
 155         pid->integral  = int_tofp(integral);
 156         pid->last_err  = setpoint - busy;
 157 }
 158
 159 static inline void pid_p_gain_set(struct _pid *pid, int percent)
 160 {
 161         pid->p_gain = div_fp(int_tofp(percent), int_tofp(100));
 162 }
 163
 164 static inline void pid_i_gain_set(struct _pid *pid, int percent)
 165 {
 166         pid->i_gain = div_fp(int_tofp(percent), int_tofp(100));
 167 }
 168
 169 static inline void pid_d_gain_set(struct _pid *pid, int percent)
 170 {
 171
 172         pid->d_gain = div_fp(int_tofp(percent), int_tofp(100));
 173 }
 174
 175 static signed int pid_calc(struct _pid *pid, int32_t busy)
 176 {
 177         signed int result;
 178         int32_t pterm, dterm, fp_error;
 179         int32_t integral_limit;
 180
 181         fp_error = int_tofp(pid->setpoint) - busy;
 182
 183         if (abs(fp_error) <= int_tofp(pid->deadband))
 184                 return 0;
 185
 186         pterm = mul_fp(pid->p_gain, fp_error);
 187
 188         pid->integral += fp_error;
 189
 190         /* limit the integral term */
 191         integral_limit = int_tofp(30);
 192         if (pid->integral > integral_limit)
 193                 pid->integral = integral_limit;
 194         if (pid->integral < -integral_limit)
 195                 pid->integral = -integral_limit;
 196
 197         dterm = mul_fp(pid->d_gain, fp_error - pid->last_err);
 198         pid->last_err = fp_error;
 199
 200         result = pterm + mul_fp(pid->integral, pid->i_gain) + dterm;
 201
 202         return (signed int)fp_toint(result);
 203 }
 204
 205 static inline void intel_pstate_busy_pid_reset(struct cpudata *cpu)
 206 {
 207         pid_p_gain_set(&cpu->pid, pid_params.p_gain_pct);
 208         pid_d_gain_set(&cpu->pid, pid_params.d_gain_pct);
 209         pid_i_gain_set(&cpu->pid, pid_params.i_gain_pct);
 210
 211         pid_reset(&cpu->pid,
 212                 pid_params.setpoint,
 213                 100,
 214                 pid_params.deadband,
 215                 0);
 216 }
 217
 218 static inline void intel_pstate_reset_all_pid(void)
 219 {
 220         unsigned int cpu;
 221         for_each_online_cpu(cpu) {
 222                 if (all_cpu_data[cpu])
 223                         intel_pstate_busy_pid_reset(all_cpu_data[cpu]);
 224         }
 225 }
 226
 227 /************************** debugfs begin ************************/
 228 static int pid_param_set(void *data, u64 val)
 229 {
 230         *(u32 *)data = val;
 231         intel_pstate_reset_all_pid();
 232         return 0;
 233 }
 234 static int pid_param_get(void *data, u64 *val)
 235 {
 236         *val = *(u32 *)data;
 237         return 0;
 238 }
 239 DEFINE_SIMPLE_ATTRIBUTE(fops_pid_param, pid_param_get,
 240                         pid_param_set, "%llu\n");
 241
 242 struct pid_param {
 243         char *name;
 244         void *value;
 245 };
 246
 247 static struct pid_param pid_files[] = {
 248         {"sample_rate_ms", &pid_params.sample_rate_ms},
 249         {"d_gain_pct", &pid_params.d_gain_pct},
 250         {"i_gain_pct", &pid_params.i_gain_pct},
 251         {"deadband", &pid_params.deadband},
 252         {"setpoint", &pid_params.setpoint},
 253         {"p_gain_pct", &pid_params.p_gain_pct},
 254         {NULL, NULL}
 255 };
 256
 257 static struct dentry *debugfs_parent;
 258 static void intel_pstate_debug_expose_params(void)
 259 {
 260         int i = 0;
 261
 262         debugfs_parent = debugfs_create_dir("pstate_snb", NULL);
 263         if (IS_ERR_OR_NULL(debugfs_parent))
 264                 return;
 265         while (pid_files[i].name) {
 266                 debugfs_create_file(pid_files[i].name, 0660,
 267                                 debugfs_parent, pid_files[i].value,
 268                                 &fops_pid_param);
 269                 i++;
 270         }
 271 }
 272
 273 /************************** debugfs end ************************/
 274
 275 /************************** sysfs begin ************************/
 276 #define show_one(file_name, object)                                     \
 277         static ssize_t show_##file_name                                 \
 278         (struct kobject *kobj, struct attribute *attr, char *buf)       \
 279         {                                                               \
 280                 return sprintf(buf, "%u\n", limits.object);             \
 281         }
 282
 283 static ssize_t store_no_turbo(struct kobject *a, struct attribute *b,
 284                                 const char *buf, size_t count)
 285 {
 286         unsigned int input;
 287         int ret;
 288         ret = sscanf(buf, "%u", &input);
 289         if (ret != 1)
 290                 return -EINVAL;
 291         limits.no_turbo = clamp_t(int, input, 0 , 1);
 292
 293         return count;
 294 }
 295
 296 static ssize_t store_max_perf_pct(struct kobject *a, struct attribute *b,
 297                                 const char *buf, size_t count)
 298 {
 299         unsigned int input;
 300         int ret;
 301         ret = sscanf(buf, "%u", &input);
 302         if (ret != 1)
 303                 return -EINVAL;
 304
 305         limits.max_sysfs_pct = clamp_t(int, input, 0 , 100);
 306         limits.max_perf_pct = min(limits.max_policy_pct, limits.max_sysfs_pct);
 307         limits.max_perf = div_fp(int_tofp(limits.max_perf_pct), int_tofp(100));
 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         ret = sscanf(buf, "%u", &input);
 317         if (ret != 1)
 318                 return -EINVAL;
 319         limits.min_perf_pct = clamp_t(int, input, 0 , 100);
 320         limits.min_perf = div_fp(int_tofp(limits.min_perf_pct), int_tofp(100));
 321
 322         return count;
 323 }
 324
 325 show_one(no_turbo, no_turbo);
 326 show_one(max_perf_pct, max_perf_pct);
 327 show_one(min_perf_pct, min_perf_pct);
 328
 329 define_one_global_rw(no_turbo);
 330 define_one_global_rw(max_perf_pct);
 331 define_one_global_rw(min_perf_pct);
 332
 333 static struct attribute *intel_pstate_attributes[] = {
 334         &no_turbo.attr,
 335         &max_perf_pct.attr,
 336         &min_perf_pct.attr,
 337         NULL
 338 };
 339
 340 static struct attribute_group intel_pstate_attr_group = {
 341         .attrs = intel_pstate_attributes,
 342 };
 343 static struct kobject *intel_pstate_kobject;
 344
 345 static void intel_pstate_sysfs_expose_params(void)
 346 {
 347         int rc;
 348
 349         intel_pstate_kobject = kobject_create_and_add("intel_pstate",
 350                                                 &cpu_subsys.dev_root->kobj);
 351         BUG_ON(!intel_pstate_kobject);
 352         rc = sysfs_create_group(intel_pstate_kobject,
 353                                 &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         rdmsrl(BYT_RATIOS, value);
 362         return (value >> 8) & 0xFF;
 363 }
 364
 365 static int byt_get_max_pstate(void)
 366 {
 367         u64 value;
 368         rdmsrl(BYT_RATIOS, value);
 369         return (value >> 16) & 0xFF;
 370 }
 371
 372 static int byt_get_turbo_pstate(void)
 373 {
 374         u64 value;
 375         rdmsrl(BYT_TURBO_RATIOS, value);
 376         return value & 0x3F;
 377 }
 378
 379 static void byt_set_pstate(struct cpudata *cpudata, int pstate)
 380 {
 381         u64 val;
 382         int32_t vid_fp;
 383         u32 vid;
 384
 385         val = pstate << 8;
 386         if (limits.no_turbo)
 387                 val |= (u64)1 << 32;
 388
 389         vid_fp = cpudata->vid.min + mul_fp(
 390                 int_tofp(pstate - cpudata->pstate.min_pstate),
 391                 cpudata->vid.ratio);
 392
 393         vid_fp = clamp_t(int32_t, vid_fp, cpudata->vid.min, cpudata->vid.max);
 394         vid = fp_toint(vid_fp);
 395
 396         val |= vid;
 397
 398         wrmsrl(MSR_IA32_PERF_CTL, val);
 399 }
 400
 401 static void byt_get_vid(struct cpudata *cpudata)
 402 {
 403         u64 value;
 404
 405         rdmsrl(BYT_VIDS, value);
 406         cpudata->vid.min = int_tofp((value >> 8) & 0x7f);
 407         cpudata->vid.max = int_tofp((value >> 16) & 0x7f);
 408         cpudata->vid.ratio = div_fp(
 409                 cpudata->vid.max - cpudata->vid.min,
 410                 int_tofp(cpudata->pstate.max_pstate -
 411                         cpudata->pstate.min_pstate));
 412 }
 413
 414
 415 static int core_get_min_pstate(void)
 416 {
 417         u64 value;
 418         rdmsrl(MSR_PLATFORM_INFO, value);
 419         return (value >> 40) & 0xFF;
 420 }
 421
 422 static int core_get_max_pstate(void)
 423 {
 424         u64 value;
 425         rdmsrl(MSR_PLATFORM_INFO, value);
 426         return (value >> 8) & 0xFF;
 427 }
 428
 429 static int core_get_turbo_pstate(void)
 430 {
 431         u64 value;
 432         int nont, ret;
 433         rdmsrl(MSR_NHM_TURBO_RATIO_LIMIT, value);
 434         nont = core_get_max_pstate();
 435         ret = ((value) & 255);
 436         if (ret <= nont)
 437                 ret = nont;
 438         return ret;
 439 }
 440
 441 static void core_set_pstate(struct cpudata *cpudata, int pstate)
 442 {
 443         u64 val;
 444
 445         val = pstate << 8;
 446         if (limits.no_turbo)
 447                 val |= (u64)1 << 32;
 448
 449         wrmsrl(MSR_IA32_PERF_CTL, val);
 450 }
 451
 452 static struct cpu_defaults core_params = {
 453         .pid_policy = {
 454                 .sample_rate_ms = 10,
 455                 .deadband = 0,
 456                 .setpoint = 97,
 457                 .p_gain_pct = 20,
 458                 .d_gain_pct = 0,
 459                 .i_gain_pct = 0,
 460         },
 461         .funcs = {
 462                 .get_max = core_get_max_pstate,
 463                 .get_min = core_get_min_pstate,
 464                 .get_turbo = core_get_turbo_pstate,
 465                 .set = core_set_pstate,
 466         },
 467 };
 468
 469 static struct cpu_defaults byt_params = {
 470         .pid_policy = {
 471                 .sample_rate_ms = 10,
 472                 .deadband = 0,
 473                 .setpoint = 97,
 474                 .p_gain_pct = 14,
 475                 .d_gain_pct = 0,
 476                 .i_gain_pct = 4,
 477         },
 478         .funcs = {
 479                 .get_max = byt_get_max_pstate,
 480                 .get_min = byt_get_min_pstate,
 481                 .get_turbo = byt_get_turbo_pstate,
 482                 .set = byt_set_pstate,
 483                 .get_vid = byt_get_vid,
 484         },
 485 };
 486
 487
 488 static void intel_pstate_get_min_max(struct cpudata *cpu, int *min, int *max)
 489 {
 490         int max_perf = cpu->pstate.turbo_pstate;
 491         int max_perf_adj;
 492         int min_perf;
 493         if (limits.no_turbo)
 494                 max_perf = cpu->pstate.max_pstate;
 495
 496         max_perf_adj = fp_toint(mul_fp(int_tofp(max_perf), limits.max_perf));
 497         *max = clamp_t(int, max_perf_adj,
 498                         cpu->pstate.min_pstate, cpu->pstate.turbo_pstate);
 499
 500         min_perf = fp_toint(mul_fp(int_tofp(max_perf), limits.min_perf));
 501         *min = clamp_t(int, min_perf,
 502                         cpu->pstate.min_pstate, max_perf);
 503 }
 504
 505 static void intel_pstate_set_pstate(struct cpudata *cpu, int pstate)
 506 {
 507         int max_perf, min_perf;
 508
 509         intel_pstate_get_min_max(cpu, &min_perf, &max_perf);
 510
 511         pstate = clamp_t(int, pstate, min_perf, max_perf);
 512
 513         if (pstate == cpu->pstate.current_pstate)
 514                 return;
 515
 516         trace_cpu_frequency(pstate * 100000, cpu->cpu);
 517
 518         cpu->pstate.current_pstate = pstate;
 519
 520         pstate_funcs.set(cpu, pstate);
 521 }
 522
 523 static inline void intel_pstate_pstate_increase(struct cpudata *cpu, int steps)
 524 {
 525         int target;
 526         target = cpu->pstate.current_pstate + steps;
 527
 528         intel_pstate_set_pstate(cpu, target);
 529 }
 530
 531 static inline void intel_pstate_pstate_decrease(struct cpudata *cpu, int steps)
 532 {
 533         int target;
 534         target = cpu->pstate.current_pstate - steps;
 535         intel_pstate_set_pstate(cpu, target);
 536 }
 537
 538 static void intel_pstate_get_cpu_pstates(struct cpudata *cpu)
 539 {
 540         sprintf(cpu->name, "Intel 2nd generation core");
 541
 542         cpu->pstate.min_pstate = pstate_funcs.get_min();
 543         cpu->pstate.max_pstate = pstate_funcs.get_max();
 544         cpu->pstate.turbo_pstate = pstate_funcs.get_turbo();
 545
 546         if (pstate_funcs.get_vid)
 547                 pstate_funcs.get_vid(cpu);
 548
 549         /*
 550          * goto max pstate so we don't slow up boot if we are built-in if we are
 551          * a module we will take care of it during normal operation
 552          */
 553         intel_pstate_set_pstate(cpu, cpu->pstate.max_pstate);
 554 }
 555
 556 static inline void intel_pstate_calc_busy(struct cpudata *cpu,
 557                                         struct sample *sample)
 558 {
 559         u64 core_pct;
 560         u64 c0_pct;
 561
 562         core_pct = div64_u64(sample->aperf * 100, sample->mperf);
 563
 564         c0_pct = div64_u64(sample->mperf * 100, sample->tsc);
 565         sample->freq = fp_toint(
 566                 mul_fp(int_tofp(cpu->pstate.max_pstate),
 567                         int_tofp(core_pct * 1000)));
 568
 569         sample->core_pct_busy = mul_fp(int_tofp(core_pct),
 570                                 div_fp(int_tofp(c0_pct + 1), int_tofp(100)));
 571 }
 572
 573 static inline void intel_pstate_sample(struct cpudata *cpu)
 574 {
 575         u64 aperf, mperf;
 576         unsigned long long tsc;
 577
 578         rdmsrl(MSR_IA32_APERF, aperf);
 579         rdmsrl(MSR_IA32_MPERF, mperf);
 580         tsc = native_read_tsc();
 581
 582         cpu->sample_ptr = (cpu->sample_ptr + 1) % SAMPLE_COUNT;
 583         cpu->samples[cpu->sample_ptr].aperf = aperf;
 584         cpu->samples[cpu->sample_ptr].mperf = mperf;
 585         cpu->samples[cpu->sample_ptr].tsc = tsc;
 586         cpu->samples[cpu->sample_ptr].aperf -= cpu->prev_aperf;
 587         cpu->samples[cpu->sample_ptr].mperf -= cpu->prev_mperf;
 588         cpu->samples[cpu->sample_ptr].tsc -= cpu->prev_tsc;
 589
 590         intel_pstate_calc_busy(cpu, &cpu->samples[cpu->sample_ptr]);
 591
 592         cpu->prev_aperf = aperf;
 593         cpu->prev_mperf = mperf;
 594         cpu->prev_tsc = tsc;
 595 }
 596
 597 static inline void intel_pstate_set_sample_time(struct cpudata *cpu)
 598 {
 599         int sample_time, delay;
 600
 601         sample_time = pid_params.sample_rate_ms;
 602         delay = msecs_to_jiffies(sample_time);
 603         mod_timer_pinned(&cpu->timer, jiffies + delay);
 604 }
 605
 606 static inline int32_t intel_pstate_get_scaled_busy(struct cpudata *cpu)
 607 {
 608         int32_t core_busy, max_pstate, current_pstate;
 609
 610         core_busy = cpu->samples[cpu->sample_ptr].core_pct_busy;
 611         max_pstate = int_tofp(cpu->pstate.max_pstate);
 612         current_pstate = int_tofp(cpu->pstate.current_pstate);
 613         return mul_fp(core_busy, div_fp(max_pstate, current_pstate));
 614 }
 615
 616 static inline void intel_pstate_adjust_busy_pstate(struct cpudata *cpu)
 617 {
 618         int32_t busy_scaled;
 619         struct _pid *pid;
 620         signed int ctl = 0;
 621         int steps;
 622
 623         pid = &cpu->pid;
 624         busy_scaled = intel_pstate_get_scaled_busy(cpu);
 625
 626         ctl = pid_calc(pid, busy_scaled);
 627
 628         steps = abs(ctl);
 629
 630         if (ctl < 0)
 631                 intel_pstate_pstate_increase(cpu, steps);
 632         else
 633                 intel_pstate_pstate_decrease(cpu, steps);
 634 }
 635
 636 static void intel_pstate_timer_func(unsigned long __data)
 637 {
 638         struct cpudata *cpu = (struct cpudata *) __data;
 639         struct sample *sample;
 640
 641         intel_pstate_sample(cpu);
 642
 643         sample = &cpu->samples[cpu->sample_ptr];
 644
 645         intel_pstate_adjust_busy_pstate(cpu);
 646
 647         trace_pstate_sample(fp_toint(sample->core_pct_busy),
 648                         fp_toint(intel_pstate_get_scaled_busy(cpu)),
 649                         cpu->pstate.current_pstate,
 650                         sample->mperf,
 651                         sample->aperf,
 652                         sample->freq);
 653
 654         intel_pstate_set_sample_time(cpu);
 655 }
 656
 657 #define ICPU(model, policy) \
 658         { X86_VENDOR_INTEL, 6, model, X86_FEATURE_APERFMPERF,\
 659                         (unsigned long)&policy }
 660
 661 static const struct x86_cpu_id intel_pstate_cpu_ids[] = {
 662         ICPU(0x2a, core_params),
 663         ICPU(0x2d, core_params),
 664         ICPU(0x37, byt_params),
 665         ICPU(0x3a, core_params),
 666         ICPU(0x3c, core_params),
 667         ICPU(0x3e, core_params),
 668         ICPU(0x3f, core_params),
 669         ICPU(0x45, core_params),
 670         ICPU(0x46, core_params),
 671         {}
 672 };
 673 MODULE_DEVICE_TABLE(x86cpu, intel_pstate_cpu_ids);
 674
 675 static int intel_pstate_init_cpu(unsigned int cpunum)
 676 {
 677
 678         const struct x86_cpu_id *id;
 679         struct cpudata *cpu;
 680
 681         id = x86_match_cpu(intel_pstate_cpu_ids);
 682         if (!id)
 683                 return -ENODEV;
 684
 685         all_cpu_data[cpunum] = kzalloc(sizeof(struct cpudata), GFP_KERNEL);
 686         if (!all_cpu_data[cpunum])
 687                 return -ENOMEM;
 688
 689         cpu = all_cpu_data[cpunum];
 690
 691         intel_pstate_get_cpu_pstates(cpu);
 692         if (!cpu->pstate.current_pstate) {
 693                 all_cpu_data[cpunum] = NULL;
 694                 kfree(cpu);
 695                 return -ENODATA;
 696         }
 697
 698         cpu->cpu = cpunum;
 699
 700         init_timer_deferrable(&cpu->timer);
 701         cpu->timer.function = intel_pstate_timer_func;
 702         cpu->timer.data =
 703                 (unsigned long)cpu;
 704         cpu->timer.expires = jiffies + HZ/100;
 705         intel_pstate_busy_pid_reset(cpu);
 706         intel_pstate_sample(cpu);
 707         intel_pstate_set_pstate(cpu, cpu->pstate.max_pstate);
 708
 709         add_timer_on(&cpu->timer, cpunum);
 710
 711         pr_info("Intel pstate controlling: cpu %d\n", cpunum);
 712
 713         return 0;
 714 }
 715
 716 static unsigned int intel_pstate_get(unsigned int cpu_num)
 717 {
 718         struct sample *sample;
 719         struct cpudata *cpu;
 720
 721         cpu = all_cpu_data[cpu_num];
 722         if (!cpu)
 723                 return 0;
 724         sample = &cpu->samples[cpu->sample_ptr];
 725         return sample->freq;
 726 }
 727
 728 static int intel_pstate_set_policy(struct cpufreq_policy *policy)
 729 {
 730         struct cpudata *cpu;
 731
 732         cpu = all_cpu_data[policy->cpu];
 733
 734         if (!policy->cpuinfo.max_freq)
 735                 return -ENODEV;
 736
 737         if (policy->policy == CPUFREQ_POLICY_PERFORMANCE) {
 738                 limits.min_perf_pct = 100;
 739                 limits.min_perf = int_tofp(1);
 740                 limits.max_perf_pct = 100;
 741                 limits.max_perf = int_tofp(1);
 742                 limits.no_turbo = 0;
 743                 return 0;
 744         }
 745         limits.min_perf_pct = (policy->min * 100) / policy->cpuinfo.max_freq;
 746         limits.min_perf_pct = clamp_t(int, limits.min_perf_pct, 0 , 100);
 747         limits.min_perf = div_fp(int_tofp(limits.min_perf_pct), int_tofp(100));
 748
 749         limits.max_policy_pct = policy->max * 100 / policy->cpuinfo.max_freq;
 750         limits.max_policy_pct = clamp_t(int, limits.max_policy_pct, 0 , 100);
 751         limits.max_perf_pct = min(limits.max_policy_pct, limits.max_sysfs_pct);
 752         limits.max_perf = div_fp(int_tofp(limits.max_perf_pct), int_tofp(100));
 753
 754         return 0;
 755 }
 756
 757 static int intel_pstate_verify_policy(struct cpufreq_policy *policy)
 758 {
 759         cpufreq_verify_within_cpu_limits(policy);
 760
 761         if ((policy->policy != CPUFREQ_POLICY_POWERSAVE) &&
 762                 (policy->policy != CPUFREQ_POLICY_PERFORMANCE))
 763                 return -EINVAL;
 764
 765         return 0;
 766 }
 767
 768 static int intel_pstate_cpu_exit(struct cpufreq_policy *policy)
 769 {
 770         int cpu = policy->cpu;
 771
 772         del_timer(&all_cpu_data[cpu]->timer);
 773         kfree(all_cpu_data[cpu]);
 774         all_cpu_data[cpu] = NULL;
 775         return 0;
 776 }
 777
 778 static int intel_pstate_cpu_init(struct cpufreq_policy *policy)
 779 {
 780         struct cpudata *cpu;
 781         int rc;
 782
 783         rc = intel_pstate_init_cpu(policy->cpu);
 784         if (rc)
 785                 return rc;
 786
 787         cpu = all_cpu_data[policy->cpu];
 788
 789         if (!limits.no_turbo &&
 790                 limits.min_perf_pct == 100 && limits.max_perf_pct == 100)
 791                 policy->policy = CPUFREQ_POLICY_PERFORMANCE;
 792         else
 793                 policy->policy = CPUFREQ_POLICY_POWERSAVE;
 794
 795         policy->min = cpu->pstate.min_pstate * 100000;
 796         policy->max = cpu->pstate.turbo_pstate * 100000;
 797
 798         /* cpuinfo and default policy values */
 799         policy->cpuinfo.min_freq = cpu->pstate.min_pstate * 100000;
 800         policy->cpuinfo.max_freq = cpu->pstate.turbo_pstate * 100000;
 801         policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
 802         cpumask_set_cpu(policy->cpu, policy->cpus);
 803
 804         return 0;
 805 }
 806
 807 static struct cpufreq_driver intel_pstate_driver = {
 808         .flags          = CPUFREQ_CONST_LOOPS,
 809         .verify         = intel_pstate_verify_policy,
 810         .setpolicy      = intel_pstate_set_policy,
 811         .get            = intel_pstate_get,
 812         .init           = intel_pstate_cpu_init,
 813         .exit           = intel_pstate_cpu_exit,
 814         .name           = "intel_pstate",
 815 };
 816
 817 static int __initdata no_load;
 818
 819 static int intel_pstate_msrs_not_valid(void)
 820 {
 821         /* Check that all the msr's we are using are valid. */
 822         u64 aperf, mperf, tmp;
 823
 824         rdmsrl(MSR_IA32_APERF, aperf);
 825         rdmsrl(MSR_IA32_MPERF, mperf);
 826
 827         if (!pstate_funcs.get_max() ||
 828                 !pstate_funcs.get_min() ||
 829                 !pstate_funcs.get_turbo())
 830                 return -ENODEV;
 831
 832         rdmsrl(MSR_IA32_APERF, tmp);
 833         if (!(tmp - aperf))
 834                 return -ENODEV;
 835
 836         rdmsrl(MSR_IA32_MPERF, tmp);
 837         if (!(tmp - mperf))
 838                 return -ENODEV;
 839
 840         return 0;
 841 }
 842
 843 static void copy_pid_params(struct pstate_adjust_policy *policy)
 844 {
 845         pid_params.sample_rate_ms = policy->sample_rate_ms;
 846         pid_params.p_gain_pct = policy->p_gain_pct;
 847         pid_params.i_gain_pct = policy->i_gain_pct;
 848         pid_params.d_gain_pct = policy->d_gain_pct;
 849         pid_params.deadband = policy->deadband;
 850         pid_params.setpoint = policy->setpoint;
 851 }
 852
 853 static void copy_cpu_funcs(struct pstate_funcs *funcs)
 854 {
 855         pstate_funcs.get_max   = funcs->get_max;
 856         pstate_funcs.get_min   = funcs->get_min;
 857         pstate_funcs.get_turbo = funcs->get_turbo;
 858         pstate_funcs.set       = funcs->set;
 859         pstate_funcs.get_vid   = funcs->get_vid;
 860 }
 861
 862 #if IS_ENABLED(CONFIG_ACPI)
 863 #include <acpi/processor.h>
 864
 865 static bool intel_pstate_no_acpi_pss(void)
 866 {
 867         int i;
 868
 869         for_each_possible_cpu(i) {
 870                 acpi_status status;
 871                 union acpi_object *pss;
 872                 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 873                 struct acpi_processor *pr = per_cpu(processors, i);
 874
 875                 if (!pr)
 876                         continue;
 877
 878                 status = acpi_evaluate_object(pr->handle, "_PSS", NULL, &buffer);
 879                 if (ACPI_FAILURE(status))
 880                         continue;
 881
 882                 pss = buffer.pointer;
 883                 if (pss && pss->type == ACPI_TYPE_PACKAGE) {
 884                         kfree(pss);
 885                         return false;
 886                 }
 887
 888                 kfree(pss);
 889         }
 890
 891         return true;
 892 }
 893
 894 struct hw_vendor_info {
 895         u16  valid;
 896         char oem_id[ACPI_OEM_ID_SIZE];
 897         char oem_table_id[ACPI_OEM_TABLE_ID_SIZE];
 898 };
 899
 900 /* Hardware vendor-specific info that has its own power management modes */
 901 static struct hw_vendor_info vendor_info[] = {
 902         {1, "HP    ", "ProLiant"},
 903         {0, "", ""},
 904 };
 905
 906 static bool intel_pstate_platform_pwr_mgmt_exists(void)
 907 {
 908         struct acpi_table_header hdr;
 909         struct hw_vendor_info *v_info;
 910
 911         if (acpi_disabled
 912             || ACPI_FAILURE(acpi_get_table_header(ACPI_SIG_FADT, 0, &hdr)))
 913                 return false;
 914
 915         for (v_info = vendor_info; v_info->valid; v_info++) {
 916                 if (!strncmp(hdr.oem_id, v_info->oem_id, ACPI_OEM_ID_SIZE)
 917                     && !strncmp(hdr.oem_table_id, v_info->oem_table_id, ACPI_OEM_TABLE_ID_SIZE)
 918                     && intel_pstate_no_acpi_pss())
 919                         return true;
 920         }
 921
 922         return false;
 923 }
 924 #else /* CONFIG_ACPI not enabled */
 925 static inline bool intel_pstate_platform_pwr_mgmt_exists(void) { return false; }
 926 #endif /* CONFIG_ACPI */
 927
 928 static int __init intel_pstate_init(void)
 929 {
 930         int cpu, rc = 0;
 931         const struct x86_cpu_id *id;
 932         struct cpu_defaults *cpu_info;
 933
 934         if (no_load)
 935                 return -ENODEV;
 936
 937         id = x86_match_cpu(intel_pstate_cpu_ids);
 938         if (!id)
 939                 return -ENODEV;
 940
 941         /*
 942          * The Intel pstate driver will be ignored if the platform
 943          * firmware has its own power management modes.
 944          */
 945         if (intel_pstate_platform_pwr_mgmt_exists())
 946                 return -ENODEV;
 947
 948         cpu_info = (struct cpu_defaults *)id->driver_data;
 949
 950         copy_pid_params(&cpu_info->pid_policy);
 951         copy_cpu_funcs(&cpu_info->funcs);
 952
 953         if (intel_pstate_msrs_not_valid())
 954                 return -ENODEV;
 955
 956         pr_info("Intel P-state driver initializing.\n");
 957
 958         all_cpu_data = vzalloc(sizeof(void *) * num_possible_cpus());
 959         if (!all_cpu_data)
 960                 return -ENOMEM;
 961
 962         rc = cpufreq_register_driver(&intel_pstate_driver);
 963         if (rc)
 964                 goto out;
 965
 966         intel_pstate_debug_expose_params();
 967         intel_pstate_sysfs_expose_params();
 968
 969         return rc;
 970 out:
 971         get_online_cpus();
 972         for_each_online_cpu(cpu) {
 973                 if (all_cpu_data[cpu]) {
 974                         del_timer_sync(&all_cpu_data[cpu]->timer);
 975                         kfree(all_cpu_data[cpu]);
 976                 }
 977         }
 978
 979         put_online_cpus();
 980         vfree(all_cpu_data);
 981         return -ENODEV;
 982 }
 983 device_initcall(intel_pstate_init);
 984
 985 static int __init intel_pstate_setup(char *str)
 986 {
 987         if (!str)
 988                 return -EINVAL;
 989
 990         if (!strcmp(str, "disable"))
 991                 no_load = 1;
 992         return 0;
 993 }
 994 early_param("intel_pstate", intel_pstate_setup);
 995
 996 MODULE_AUTHOR("Dirk Brandewie <dirk.j.brandewie@intel.com>");
 997 MODULE_DESCRIPTION("'intel_pstate' - P state driver Intel Core processors");
 998 MODULE_LICENSE("GPL");