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 <[email protected]>
   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 static inline int ceiling_fp(int32_t x)
  56 {
  57         int mask, ret;
  58
  59         ret = fp_toint(x);
  60         mask = (1 << FRAC_BITS) - 1;
  61         if (x & mask)
  62                 ret += 1;
  63         return ret;
  64 }
  65
  66 struct sample {
  67         int32_t core_pct_busy;
  68         u64 aperf;
  69         u64 mperf;
  70         int freq;
  71         ktime_t time;
  72 };
  73
  74 struct pstate_data {
  75         int     current_pstate;
  76         int     min_pstate;
  77         int     max_pstate;
  78         int     scaling;
  79         int     turbo_pstate;
  80 };
  81
  82 struct vid_data {
  83         int min;
  84         int max;
  85         int turbo;
  86         int32_t ratio;
  87 };
  88
  89 struct _pid {
  90         int setpoint;
  91         int32_t integral;
  92         int32_t p_gain;
  93         int32_t i_gain;
  94         int32_t d_gain;
  95         int deadband;
  96         int32_t last_err;
  97 };
  98
  99 struct cpudata {
 100         int cpu;
 101
 102         struct timer_list timer;
 103
 104         struct pstate_data pstate;
 105         struct vid_data vid;
 106         struct _pid pid;
 107
 108         ktime_t last_sample_time;
 109         u64     prev_aperf;
 110         u64     prev_mperf;
 111         struct sample sample;
 112 };
 113
 114 static struct cpudata **all_cpu_data;
 115 struct pstate_adjust_policy {
 116         int sample_rate_ms;
 117         int deadband;
 118         int setpoint;
 119         int p_gain_pct;
 120         int d_gain_pct;
 121         int i_gain_pct;
 122 };
 123
 124 struct pstate_funcs {
 125         int (*get_max)(void);
 126         int (*get_min)(void);
 127         int (*get_turbo)(void);
 128         int (*get_scaling)(void);
 129         void (*set)(struct cpudata*, int pstate);
 130         void (*get_vid)(struct cpudata *);
 131 };
 132
 133 struct cpu_defaults {
 134         struct pstate_adjust_policy pid_policy;
 135         struct pstate_funcs funcs;
 136 };
 137
 138 static struct pstate_adjust_policy pid_params;
 139 static struct pstate_funcs pstate_funcs;
 140
 141 struct perf_limits {
 142         int no_turbo;
 143         int turbo_disabled;
 144         int max_perf_pct;
 145         int min_perf_pct;
 146         int32_t max_perf;
 147         int32_t min_perf;
 148         int max_policy_pct;
 149         int max_sysfs_pct;
 150 };
 151
 152 static struct perf_limits limits = {
 153         .no_turbo = 0,
 154         .turbo_disabled = 0,
 155         .max_perf_pct = 100,
 156         .max_perf = int_tofp(1),
 157         .min_perf_pct = 0,
 158         .min_perf = 0,
 159         .max_policy_pct = 100,
 160         .max_sysfs_pct = 100,
 161 };
 162
 163 static inline void pid_reset(struct _pid *pid, int setpoint, int busy,
 164                              int deadband, int integral) {
 165         pid->setpoint = setpoint;
 166         pid->deadband  = deadband;
 167         pid->integral  = int_tofp(integral);
 168         pid->last_err  = int_tofp(setpoint) - int_tofp(busy);
 169 }
 170
 171 static inline void pid_p_gain_set(struct _pid *pid, int percent)
 172 {
 173         pid->p_gain = div_fp(int_tofp(percent), int_tofp(100));
 174 }
 175
 176 static inline void pid_i_gain_set(struct _pid *pid, int percent)
 177 {
 178         pid->i_gain = div_fp(int_tofp(percent), int_tofp(100));
 179 }
 180
 181 static inline void pid_d_gain_set(struct _pid *pid, int percent)
 182 {
 183         pid->d_gain = div_fp(int_tofp(percent), int_tofp(100));
 184 }
 185
 186 static signed int pid_calc(struct _pid *pid, int32_t busy)
 187 {
 188         signed int result;
 189         int32_t pterm, dterm, fp_error;
 190         int32_t integral_limit;
 191
 192         fp_error = int_tofp(pid->setpoint) - busy;
 193
 194         if (abs(fp_error) <= int_tofp(pid->deadband))
 195                 return 0;
 196
 197         pterm = mul_fp(pid->p_gain, fp_error);
 198
 199         pid->integral += fp_error;
 200
 201         /* limit the integral term */
 202         integral_limit = int_tofp(30);
 203         if (pid->integral > integral_limit)
 204                 pid->integral = integral_limit;
 205         if (pid->integral < -integral_limit)
 206                 pid->integral = -integral_limit;
 207
 208         dterm = mul_fp(pid->d_gain, fp_error - pid->last_err);
 209         pid->last_err = fp_error;
 210
 211         result = pterm + mul_fp(pid->integral, pid->i_gain) + dterm;
 212         result = result + (1 << (FRAC_BITS-1));
 213         return (signed int)fp_toint(result);
 214 }
 215
 216 static inline void intel_pstate_busy_pid_reset(struct cpudata *cpu)
 217 {
 218         pid_p_gain_set(&cpu->pid, pid_params.p_gain_pct);
 219         pid_d_gain_set(&cpu->pid, pid_params.d_gain_pct);
 220         pid_i_gain_set(&cpu->pid, pid_params.i_gain_pct);
 221
 222         pid_reset(&cpu->pid, pid_params.setpoint, 100, pid_params.deadband, 0);
 223 }
 224
 225 static inline void intel_pstate_reset_all_pid(void)
 226 {
 227         unsigned int cpu;
 228
 229         for_each_online_cpu(cpu) {
 230                 if (all_cpu_data[cpu])
 231                         intel_pstate_busy_pid_reset(all_cpu_data[cpu]);
 232         }
 233 }
 234
 235 static inline void update_turbo_state(void)
 236 {
 237         u64 misc_en;
 238         struct cpudata *cpu;
 239
 240         cpu = all_cpu_data[0];
 241         rdmsrl(MSR_IA32_MISC_ENABLE, misc_en);
 242         limits.turbo_disabled =
 243                 (misc_en & MSR_IA32_MISC_ENABLE_TURBO_DISABLE ||
 244                  cpu->pstate.max_pstate == cpu->pstate.turbo_pstate);
 245 }
 246
 247 /************************** debugfs begin ************************/
 248 static int pid_param_set(void *data, u64 val)
 249 {
 250         *(u32 *)data = val;
 251         intel_pstate_reset_all_pid();
 252         return 0;
 253 }
 254
 255 static int pid_param_get(void *data, u64 *val)
 256 {
 257         *val = *(u32 *)data;
 258         return 0;
 259 }
 260 DEFINE_SIMPLE_ATTRIBUTE(fops_pid_param, pid_param_get, pid_param_set, "%llu\n");
 261
 262 struct pid_param {
 263         char *name;
 264         void *value;
 265 };
 266
 267 static struct pid_param pid_files[] = {
 268         {"sample_rate_ms", &pid_params.sample_rate_ms},
 269         {"d_gain_pct", &pid_params.d_gain_pct},
 270         {"i_gain_pct", &pid_params.i_gain_pct},
 271         {"deadband", &pid_params.deadband},
 272         {"setpoint", &pid_params.setpoint},
 273         {"p_gain_pct", &pid_params.p_gain_pct},
 274         {NULL, NULL}
 275 };
 276
 277 static void __init intel_pstate_debug_expose_params(void)
 278 {
 279         struct dentry *debugfs_parent;
 280         int i = 0;
 281
 282         debugfs_parent = debugfs_create_dir("pstate_snb", NULL);
 283         if (IS_ERR_OR_NULL(debugfs_parent))
 284                 return;
 285         while (pid_files[i].name) {
 286                 debugfs_create_file(pid_files[i].name, 0660,
 287                                     debugfs_parent, pid_files[i].value,
 288                                     &fops_pid_param);
 289                 i++;
 290         }
 291 }
 292
 293 /************************** debugfs end ************************/
 294
 295 /************************** sysfs begin ************************/
 296 #define show_one(file_name, object)                                     \
 297         static ssize_t show_##file_name                                 \
 298         (struct kobject *kobj, struct attribute *attr, char *buf)       \
 299         {                                                               \
 300                 return sprintf(buf, "%u\n", limits.object);             \
 301         }
 302
 303 static ssize_t show_no_turbo(struct kobject *kobj,
 304                              struct attribute *attr, char *buf)
 305 {
 306         ssize_t ret;
 307
 308         update_turbo_state();
 309         if (limits.turbo_disabled)
 310                 ret = sprintf(buf, "%u\n", limits.turbo_disabled);
 311         else
 312                 ret = sprintf(buf, "%u\n", limits.no_turbo);
 313
 314         return ret;
 315 }
 316
 317 static ssize_t store_no_turbo(struct kobject *a, struct attribute *b,
 318                               const char *buf, size_t count)
 319 {
 320         unsigned int input;
 321         int ret;
 322
 323         ret = sscanf(buf, "%u", &input);
 324         if (ret != 1)
 325                 return -EINVAL;
 326
 327         update_turbo_state();
 328         if (limits.turbo_disabled) {
 329                 pr_warn("Turbo disabled by BIOS or unavailable on processor\n");
 330                 return -EPERM;
 331         }
 332         limits.no_turbo = clamp_t(int, input, 0, 1);
 333
 334         return count;
 335 }
 336
 337 static ssize_t store_max_perf_pct(struct kobject *a, struct attribute *b,
 338                                   const char *buf, size_t count)
 339 {
 340         unsigned int input;
 341         int ret;
 342
 343         ret = sscanf(buf, "%u", &input);
 344         if (ret != 1)
 345                 return -EINVAL;
 346
 347         limits.max_sysfs_pct = clamp_t(int, input, 0 , 100);
 348         limits.max_perf_pct = min(limits.max_policy_pct, limits.max_sysfs_pct);
 349         limits.max_perf = div_fp(int_tofp(limits.max_perf_pct), int_tofp(100));
 350
 351         return count;
 352 }
 353
 354 static ssize_t store_min_perf_pct(struct kobject *a, struct attribute *b,
 355                                   const char *buf, size_t count)
 356 {
 357         unsigned int input;
 358         int ret;
 359
 360         ret = sscanf(buf, "%u", &input);
 361         if (ret != 1)
 362                 return -EINVAL;
 363         limits.min_perf_pct = clamp_t(int, input, 0 , 100);
 364         limits.min_perf = div_fp(int_tofp(limits.min_perf_pct), int_tofp(100));
 365
 366         return count;
 367 }
 368
 369 show_one(max_perf_pct, max_perf_pct);
 370 show_one(min_perf_pct, min_perf_pct);
 371
 372 define_one_global_rw(no_turbo);
 373 define_one_global_rw(max_perf_pct);
 374 define_one_global_rw(min_perf_pct);
 375
 376 static struct attribute *intel_pstate_attributes[] = {
 377         &no_turbo.attr,
 378         &max_perf_pct.attr,
 379         &min_perf_pct.attr,
 380         NULL
 381 };
 382
 383 static struct attribute_group intel_pstate_attr_group = {
 384         .attrs = intel_pstate_attributes,
 385 };
 386
 387 static void __init intel_pstate_sysfs_expose_params(void)
 388 {
 389         struct kobject *intel_pstate_kobject;
 390         int rc;
 391
 392         intel_pstate_kobject = kobject_create_and_add("intel_pstate",
 393                                                 &cpu_subsys.dev_root->kobj);
 394         BUG_ON(!intel_pstate_kobject);
 395         rc = sysfs_create_group(intel_pstate_kobject, &intel_pstate_attr_group);
 396         BUG_ON(rc);
 397 }
 398
 399 /************************** sysfs end ************************/
 400 static int byt_get_min_pstate(void)
 401 {
 402         u64 value;
 403
 404         rdmsrl(BYT_RATIOS, value);
 405         return (value >> 8) & 0x7F;
 406 }
 407
 408 static int byt_get_max_pstate(void)
 409 {
 410         u64 value;
 411
 412         rdmsrl(BYT_RATIOS, value);
 413         return (value >> 16) & 0x7F;
 414 }
 415
 416 static int byt_get_turbo_pstate(void)
 417 {
 418         u64 value;
 419
 420         rdmsrl(BYT_TURBO_RATIOS, value);
 421         return value & 0x7F;
 422 }
 423
 424 static void byt_set_pstate(struct cpudata *cpudata, int pstate)
 425 {
 426         u64 val;
 427         int32_t vid_fp;
 428         u32 vid;
 429
 430         val = pstate << 8;
 431         if (limits.no_turbo && !limits.turbo_disabled)
 432                 val |= (u64)1 << 32;
 433
 434         vid_fp = cpudata->vid.min + mul_fp(
 435                 int_tofp(pstate - cpudata->pstate.min_pstate),
 436                 cpudata->vid.ratio);
 437
 438         vid_fp = clamp_t(int32_t, vid_fp, cpudata->vid.min, cpudata->vid.max);
 439         vid = ceiling_fp(vid_fp);
 440
 441         if (pstate > cpudata->pstate.max_pstate)
 442                 vid = cpudata->vid.turbo;
 443
 444         val |= vid;
 445
 446         wrmsrl(MSR_IA32_PERF_CTL, val);
 447 }
 448
 449 #define BYT_BCLK_FREQS 5
 450 static int byt_freq_table[BYT_BCLK_FREQS] = { 833, 1000, 1333, 1167, 800};
 451
 452 static int byt_get_scaling(void)
 453 {
 454         u64 value;
 455         int i;
 456
 457         rdmsrl(MSR_FSB_FREQ, value);
 458         i = value & 0x3;
 459
 460         BUG_ON(i > BYT_BCLK_FREQS);
 461
 462         return byt_freq_table[i] * 100;
 463 }
 464
 465 static void byt_get_vid(struct cpudata *cpudata)
 466 {
 467         u64 value;
 468
 469         rdmsrl(BYT_VIDS, value);
 470         cpudata->vid.min = int_tofp((value >> 8) & 0x7f);
 471         cpudata->vid.max = int_tofp((value >> 16) & 0x7f);
 472         cpudata->vid.ratio = div_fp(
 473                 cpudata->vid.max - cpudata->vid.min,
 474                 int_tofp(cpudata->pstate.max_pstate -
 475                         cpudata->pstate.min_pstate));
 476
 477         rdmsrl(BYT_TURBO_VIDS, value);
 478         cpudata->vid.turbo = value & 0x7f;
 479 }
 480
 481 static int core_get_min_pstate(void)
 482 {
 483         u64 value;
 484
 485         rdmsrl(MSR_PLATFORM_INFO, value);
 486         return (value >> 40) & 0xFF;
 487 }
 488
 489 static int core_get_max_pstate(void)
 490 {
 491         u64 value;
 492
 493         rdmsrl(MSR_PLATFORM_INFO, value);
 494         return (value >> 8) & 0xFF;
 495 }
 496
 497 static int core_get_turbo_pstate(void)
 498 {
 499         u64 value;
 500         int nont, ret;
 501
 502         rdmsrl(MSR_NHM_TURBO_RATIO_LIMIT, value);
 503         nont = core_get_max_pstate();
 504         ret = (value) & 255;
 505         if (ret <= nont)
 506                 ret = nont;
 507         return ret;
 508 }
 509
 510 static inline int core_get_scaling(void)
 511 {
 512         return 100000;
 513 }
 514
 515 static void core_set_pstate(struct cpudata *cpudata, int pstate)
 516 {
 517         u64 val;
 518
 519         val = pstate << 8;
 520         if (limits.no_turbo && !limits.turbo_disabled)
 521                 val |= (u64)1 << 32;
 522
 523         wrmsrl_on_cpu(cpudata->cpu, MSR_IA32_PERF_CTL, val);
 524 }
 525
 526 static struct cpu_defaults core_params = {
 527         .pid_policy = {
 528                 .sample_rate_ms = 10,
 529                 .deadband = 0,
 530                 .setpoint = 97,
 531                 .p_gain_pct = 20,
 532                 .d_gain_pct = 0,
 533                 .i_gain_pct = 0,
 534         },
 535         .funcs = {
 536                 .get_max = core_get_max_pstate,
 537                 .get_min = core_get_min_pstate,
 538                 .get_turbo = core_get_turbo_pstate,
 539                 .get_scaling = core_get_scaling,
 540                 .set = core_set_pstate,
 541         },
 542 };
 543
 544 static struct cpu_defaults byt_params = {
 545         .pid_policy = {
 546                 .sample_rate_ms = 10,
 547                 .deadband = 0,
 548                 .setpoint = 97,
 549                 .p_gain_pct = 14,
 550                 .d_gain_pct = 0,
 551                 .i_gain_pct = 4,
 552         },
 553         .funcs = {
 554                 .get_max = byt_get_max_pstate,
 555                 .get_min = byt_get_min_pstate,
 556                 .get_turbo = byt_get_turbo_pstate,
 557                 .set = byt_set_pstate,
 558                 .get_scaling = byt_get_scaling,
 559                 .get_vid = byt_get_vid,
 560         },
 561 };
 562
 563 static void intel_pstate_get_min_max(struct cpudata *cpu, int *min, int *max)
 564 {
 565         int max_perf = cpu->pstate.turbo_pstate;
 566         int max_perf_adj;
 567         int min_perf;
 568
 569         if (limits.no_turbo || limits.turbo_disabled)
 570                 max_perf = cpu->pstate.max_pstate;
 571
 572         max_perf_adj = fp_toint(mul_fp(int_tofp(max_perf), limits.max_perf));
 573         *max = clamp_t(int, max_perf_adj,
 574                         cpu->pstate.min_pstate, cpu->pstate.turbo_pstate);
 575
 576         min_perf = fp_toint(mul_fp(int_tofp(max_perf), limits.min_perf));
 577         *min = clamp_t(int, min_perf, cpu->pstate.min_pstate, max_perf);
 578 }
 579
 580 static void intel_pstate_set_pstate(struct cpudata *cpu, int pstate)
 581 {
 582         int max_perf, min_perf;
 583
 584         update_turbo_state();
 585
 586         intel_pstate_get_min_max(cpu, &min_perf, &max_perf);
 587
 588         pstate = clamp_t(int, pstate, min_perf, max_perf);
 589
 590         if (pstate == cpu->pstate.current_pstate)
 591                 return;
 592
 593         trace_cpu_frequency(pstate * cpu->pstate.scaling, cpu->cpu);
 594
 595         cpu->pstate.current_pstate = pstate;
 596
 597         pstate_funcs.set(cpu, pstate);
 598 }
 599
 600 static void intel_pstate_get_cpu_pstates(struct cpudata *cpu)
 601 {
 602         cpu->pstate.min_pstate = pstate_funcs.get_min();
 603         cpu->pstate.max_pstate = pstate_funcs.get_max();
 604         cpu->pstate.turbo_pstate = pstate_funcs.get_turbo();
 605         cpu->pstate.scaling = pstate_funcs.get_scaling();
 606
 607         if (pstate_funcs.get_vid)
 608                 pstate_funcs.get_vid(cpu);
 609         intel_pstate_set_pstate(cpu, cpu->pstate.min_pstate);
 610 }
 611
 612 static inline void intel_pstate_calc_busy(struct cpudata *cpu)
 613 {
 614         struct sample *sample = &cpu->sample;
 615         int64_t core_pct;
 616
 617         core_pct = int_tofp(sample->aperf) * int_tofp(100);
 618         core_pct = div64_u64(core_pct, int_tofp(sample->mperf));
 619
 620         sample->freq = fp_toint(
 621                 mul_fp(int_tofp(
 622                         cpu->pstate.max_pstate * cpu->pstate.scaling / 100),
 623                         core_pct));
 624
 625         sample->core_pct_busy = (int32_t)core_pct;
 626 }
 627
 628 static inline void intel_pstate_sample(struct cpudata *cpu)
 629 {
 630         u64 aperf, mperf;
 631         unsigned long flags;
 632
 633         local_irq_save(flags);
 634         rdmsrl(MSR_IA32_APERF, aperf);
 635         rdmsrl(MSR_IA32_MPERF, mperf);
 636         local_irq_restore(flags);
 637
 638         cpu->last_sample_time = cpu->sample.time;
 639         cpu->sample.time = ktime_get();
 640         cpu->sample.aperf = aperf;
 641         cpu->sample.mperf = mperf;
 642         cpu->sample.aperf -= cpu->prev_aperf;
 643         cpu->sample.mperf -= cpu->prev_mperf;
 644
 645         intel_pstate_calc_busy(cpu);
 646
 647         cpu->prev_aperf = aperf;
 648         cpu->prev_mperf = mperf;
 649 }
 650
 651 static inline void intel_pstate_set_sample_time(struct cpudata *cpu)
 652 {
 653         int delay;
 654
 655         delay = msecs_to_jiffies(pid_params.sample_rate_ms);
 656         mod_timer_pinned(&cpu->timer, jiffies + delay);
 657 }
 658
 659 static inline int32_t intel_pstate_get_scaled_busy(struct cpudata *cpu)
 660 {
 661         int32_t core_busy, max_pstate, current_pstate, sample_ratio;
 662         u32 duration_us;
 663         u32 sample_time;
 664
 665         core_busy = cpu->sample.core_pct_busy;
 666         max_pstate = int_tofp(cpu->pstate.max_pstate);
 667         current_pstate = int_tofp(cpu->pstate.current_pstate);
 668         core_busy = mul_fp(core_busy, div_fp(max_pstate, current_pstate));
 669
 670         sample_time = pid_params.sample_rate_ms  * USEC_PER_MSEC;
 671         duration_us = (u32) ktime_us_delta(cpu->sample.time,
 672                                            cpu->last_sample_time);
 673         if (duration_us > sample_time * 3) {
 674                 sample_ratio = div_fp(int_tofp(sample_time),
 675                                       int_tofp(duration_us));
 676                 core_busy = mul_fp(core_busy, sample_ratio);
 677         }
 678
 679         return core_busy;
 680 }
 681
 682 static inline void intel_pstate_adjust_busy_pstate(struct cpudata *cpu)
 683 {
 684         int32_t busy_scaled;
 685         struct _pid *pid;
 686         signed int ctl;
 687
 688         pid = &cpu->pid;
 689         busy_scaled = intel_pstate_get_scaled_busy(cpu);
 690
 691         ctl = pid_calc(pid, busy_scaled);
 692
 693         /* Negative values of ctl increase the pstate and vice versa */
 694         intel_pstate_set_pstate(cpu, cpu->pstate.current_pstate - ctl);
 695 }
 696
 697 static void intel_pstate_timer_func(unsigned long __data)
 698 {
 699         struct cpudata *cpu = (struct cpudata *) __data;
 700         struct sample *sample;
 701
 702         intel_pstate_sample(cpu);
 703
 704         sample = &cpu->sample;
 705
 706         intel_pstate_adjust_busy_pstate(cpu);
 707
 708         trace_pstate_sample(fp_toint(sample->core_pct_busy),
 709                         fp_toint(intel_pstate_get_scaled_busy(cpu)),
 710                         cpu->pstate.current_pstate,
 711                         sample->mperf,
 712                         sample->aperf,
 713                         sample->freq);
 714
 715         intel_pstate_set_sample_time(cpu);
 716 }
 717
 718 #define ICPU(model, policy) \
 719         { X86_VENDOR_INTEL, 6, model, X86_FEATURE_APERFMPERF,\
 720                         (unsigned long)&policy }
 721
 722 static const struct x86_cpu_id intel_pstate_cpu_ids[] = {
 723         ICPU(0x2a, core_params),
 724         ICPU(0x2d, core_params),
 725         ICPU(0x37, byt_params),
 726         ICPU(0x3a, core_params),
 727         ICPU(0x3c, core_params),
 728         ICPU(0x3d, core_params),
 729         ICPU(0x3e, core_params),
 730         ICPU(0x3f, core_params),
 731         ICPU(0x45, core_params),
 732         ICPU(0x46, core_params),
 733         ICPU(0x4c, byt_params),
 734         ICPU(0x4f, core_params),
 735         ICPU(0x56, core_params),
 736         {}
 737 };
 738 MODULE_DEVICE_TABLE(x86cpu, intel_pstate_cpu_ids);
 739
 740 static int intel_pstate_init_cpu(unsigned int cpunum)
 741 {
 742         struct cpudata *cpu;
 743
 744         if (!all_cpu_data[cpunum])
 745                 all_cpu_data[cpunum] = kzalloc(sizeof(struct cpudata),
 746                                                GFP_KERNEL);
 747         if (!all_cpu_data[cpunum])
 748                 return -ENOMEM;
 749
 750         cpu = all_cpu_data[cpunum];
 751
 752         cpu->cpu = cpunum;
 753         intel_pstate_get_cpu_pstates(cpu);
 754
 755         init_timer_deferrable(&cpu->timer);
 756         cpu->timer.function = intel_pstate_timer_func;
 757         cpu->timer.data = (unsigned long)cpu;
 758         cpu->timer.expires = jiffies + HZ/100;
 759         intel_pstate_busy_pid_reset(cpu);
 760         intel_pstate_sample(cpu);
 761
 762         add_timer_on(&cpu->timer, cpunum);
 763
 764         pr_debug("Intel pstate controlling: cpu %d\n", cpunum);
 765
 766         return 0;
 767 }
 768
 769 static unsigned int intel_pstate_get(unsigned int cpu_num)
 770 {
 771         struct sample *sample;
 772         struct cpudata *cpu;
 773
 774         cpu = all_cpu_data[cpu_num];
 775         if (!cpu)
 776                 return 0;
 777         sample = &cpu->sample;
 778         return sample->freq;
 779 }
 780
 781 static int intel_pstate_set_policy(struct cpufreq_policy *policy)
 782 {
 783         if (!policy->cpuinfo.max_freq)
 784                 return -ENODEV;
 785
 786         if (policy->policy == CPUFREQ_POLICY_PERFORMANCE) {
 787                 limits.min_perf_pct = 100;
 788                 limits.min_perf = int_tofp(1);
 789                 limits.max_policy_pct = 100;
 790                 limits.max_perf_pct = 100;
 791                 limits.max_perf = int_tofp(1);
 792                 limits.no_turbo = 0;
 793                 return 0;
 794         }
 795         limits.min_perf_pct = (policy->min * 100) / policy->cpuinfo.max_freq;
 796         limits.min_perf_pct = clamp_t(int, limits.min_perf_pct, 0 , 100);
 797         limits.min_perf = div_fp(int_tofp(limits.min_perf_pct), int_tofp(100));
 798
 799         limits.max_policy_pct = (policy->max * 100) / policy->cpuinfo.max_freq;
 800         limits.max_policy_pct = clamp_t(int, limits.max_policy_pct, 0 , 100);
 801         limits.max_perf_pct = min(limits.max_policy_pct, limits.max_sysfs_pct);
 802         limits.max_perf = div_fp(int_tofp(limits.max_perf_pct), int_tofp(100));
 803
 804         return 0;
 805 }
 806
 807 static int intel_pstate_verify_policy(struct cpufreq_policy *policy)
 808 {
 809         cpufreq_verify_within_cpu_limits(policy);
 810
 811         if (policy->policy != CPUFREQ_POLICY_POWERSAVE &&
 812             policy->policy != CPUFREQ_POLICY_PERFORMANCE)
 813                 return -EINVAL;
 814
 815         return 0;
 816 }
 817
 818 static void intel_pstate_stop_cpu(struct cpufreq_policy *policy)
 819 {
 820         int cpu_num = policy->cpu;
 821         struct cpudata *cpu = all_cpu_data[cpu_num];
 822
 823         pr_info("intel_pstate CPU %d exiting\n", cpu_num);
 824
 825         del_timer_sync(&all_cpu_data[cpu_num]->timer);
 826         intel_pstate_set_pstate(cpu, cpu->pstate.min_pstate);
 827 }
 828
 829 static int intel_pstate_cpu_init(struct cpufreq_policy *policy)
 830 {
 831         struct cpudata *cpu;
 832         int rc;
 833
 834         rc = intel_pstate_init_cpu(policy->cpu);
 835         if (rc)
 836                 return rc;
 837
 838         cpu = all_cpu_data[policy->cpu];
 839
 840         if (limits.min_perf_pct == 100 && limits.max_perf_pct == 100)
 841                 policy->policy = CPUFREQ_POLICY_PERFORMANCE;
 842         else
 843                 policy->policy = CPUFREQ_POLICY_POWERSAVE;
 844
 845         policy->min = cpu->pstate.min_pstate * cpu->pstate.scaling;
 846         policy->max = cpu->pstate.turbo_pstate * cpu->pstate.scaling;
 847
 848         /* cpuinfo and default policy values */
 849         policy->cpuinfo.min_freq = cpu->pstate.min_pstate * cpu->pstate.scaling;
 850         policy->cpuinfo.max_freq =
 851                 cpu->pstate.turbo_pstate * cpu->pstate.scaling;
 852         policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
 853         cpumask_set_cpu(policy->cpu, policy->cpus);
 854
 855         return 0;
 856 }
 857
 858 static struct cpufreq_driver intel_pstate_driver = {
 859         .flags          = CPUFREQ_CONST_LOOPS,
 860         .verify         = intel_pstate_verify_policy,
 861         .setpolicy      = intel_pstate_set_policy,
 862         .get            = intel_pstate_get,
 863         .init           = intel_pstate_cpu_init,
 864         .stop_cpu       = intel_pstate_stop_cpu,
 865         .name           = "intel_pstate",
 866 };
 867
 868 static int __initdata no_load;
 869
 870 static int intel_pstate_msrs_not_valid(void)
 871 {
 872         /* Check that all the msr's we are using are valid. */
 873         u64 aperf, mperf, tmp;
 874
 875         rdmsrl(MSR_IA32_APERF, aperf);
 876         rdmsrl(MSR_IA32_MPERF, mperf);
 877
 878         if (!pstate_funcs.get_max() ||
 879             !pstate_funcs.get_min() ||
 880             !pstate_funcs.get_turbo())
 881                 return -ENODEV;
 882
 883         rdmsrl(MSR_IA32_APERF, tmp);
 884         if (!(tmp - aperf))
 885                 return -ENODEV;
 886
 887         rdmsrl(MSR_IA32_MPERF, tmp);
 888         if (!(tmp - mperf))
 889                 return -ENODEV;
 890
 891         return 0;
 892 }
 893
 894 static void copy_pid_params(struct pstate_adjust_policy *policy)
 895 {
 896         pid_params.sample_rate_ms = policy->sample_rate_ms;
 897         pid_params.p_gain_pct = policy->p_gain_pct;
 898         pid_params.i_gain_pct = policy->i_gain_pct;
 899         pid_params.d_gain_pct = policy->d_gain_pct;
 900         pid_params.deadband = policy->deadband;
 901         pid_params.setpoint = policy->setpoint;
 902 }
 903
 904 static void copy_cpu_funcs(struct pstate_funcs *funcs)
 905 {
 906         pstate_funcs.get_max   = funcs->get_max;
 907         pstate_funcs.get_min   = funcs->get_min;
 908         pstate_funcs.get_turbo = funcs->get_turbo;
 909         pstate_funcs.get_scaling = funcs->get_scaling;
 910         pstate_funcs.set       = funcs->set;
 911         pstate_funcs.get_vid   = funcs->get_vid;
 912 }
 913
 914 #if IS_ENABLED(CONFIG_ACPI)
 915 #include <acpi/processor.h>
 916
 917 static bool intel_pstate_no_acpi_pss(void)
 918 {
 919         int i;
 920
 921         for_each_possible_cpu(i) {
 922                 acpi_status status;
 923                 union acpi_object *pss;
 924                 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 925                 struct acpi_processor *pr = per_cpu(processors, i);
 926
 927                 if (!pr)
 928                         continue;
 929
 930                 status = acpi_evaluate_object(pr->handle, "_PSS", NULL, &buffer);
 931                 if (ACPI_FAILURE(status))
 932                         continue;
 933
 934                 pss = buffer.pointer;
 935                 if (pss && pss->type == ACPI_TYPE_PACKAGE) {
 936                         kfree(pss);
 937                         return false;
 938                 }
 939
 940                 kfree(pss);
 941         }
 942
 943         return true;
 944 }
 945
 946 struct hw_vendor_info {
 947         u16  valid;
 948         char oem_id[ACPI_OEM_ID_SIZE];
 949         char oem_table_id[ACPI_OEM_TABLE_ID_SIZE];
 950 };
 951
 952 /* Hardware vendor-specific info that has its own power management modes */
 953 static struct hw_vendor_info vendor_info[] = {
 954         {1, "HP    ", "ProLiant"},
 955         {0, "", ""},
 956 };
 957
 958 static bool intel_pstate_platform_pwr_mgmt_exists(void)
 959 {
 960         struct acpi_table_header hdr;
 961         struct hw_vendor_info *v_info;
 962
 963         if (acpi_disabled ||
 964             ACPI_FAILURE(acpi_get_table_header(ACPI_SIG_FADT, 0, &hdr)))
 965                 return false;
 966
 967         for (v_info = vendor_info; v_info->valid; v_info++) {
 968                 if (!strncmp(hdr.oem_id, v_info->oem_id, ACPI_OEM_ID_SIZE) &&
 969                     !strncmp(hdr.oem_table_id, v_info->oem_table_id, ACPI_OEM_TABLE_ID_SIZE) &&
 970                     intel_pstate_no_acpi_pss())
 971                         return true;
 972         }
 973
 974         return false;
 975 }
 976 #else /* CONFIG_ACPI not enabled */
 977 static inline bool intel_pstate_platform_pwr_mgmt_exists(void) { return false; }
 978 #endif /* CONFIG_ACPI */
 979
 980 static int __init intel_pstate_init(void)
 981 {
 982         int cpu, rc = 0;
 983         const struct x86_cpu_id *id;
 984         struct cpu_defaults *cpu_info;
 985
 986         if (no_load)
 987                 return -ENODEV;
 988
 989         id = x86_match_cpu(intel_pstate_cpu_ids);
 990         if (!id)
 991                 return -ENODEV;
 992
 993         /*
 994          * The Intel pstate driver will be ignored if the platform
 995          * firmware has its own power management modes.
 996          */
 997         if (intel_pstate_platform_pwr_mgmt_exists())
 998                 return -ENODEV;
 999
1000         cpu_info = (struct cpu_defaults *)id->driver_data;
1001
1002         copy_pid_params(&cpu_info->pid_policy);
1003         copy_cpu_funcs(&cpu_info->funcs);
1004
1005         if (intel_pstate_msrs_not_valid())
1006                 return -ENODEV;
1007
1008         pr_info("Intel P-state driver initializing.\n");
1009
1010         all_cpu_data = vzalloc(sizeof(void *) * num_possible_cpus());
1011         if (!all_cpu_data)
1012                 return -ENOMEM;
1013
1014         rc = cpufreq_register_driver(&intel_pstate_driver);
1015         if (rc)
1016                 goto out;
1017
1018         intel_pstate_debug_expose_params();
1019         intel_pstate_sysfs_expose_params();
1020
1021         return rc;
1022 out:
1023         get_online_cpus();
1024         for_each_online_cpu(cpu) {
1025                 if (all_cpu_data[cpu]) {
1026                         del_timer_sync(&all_cpu_data[cpu]->timer);
1027                         kfree(all_cpu_data[cpu]);
1028                 }
1029         }
1030
1031         put_online_cpus();
1032         vfree(all_cpu_data);
1033         return -ENODEV;
1034 }
1035 device_initcall(intel_pstate_init);
1036
1037 static int __init intel_pstate_setup(char *str)
1038 {
1039         if (!str)
1040                 return -EINVAL;
1041
1042         if (!strcmp(str, "disable"))
1043                 no_load = 1;
1044         return 0;
1045 }
1046 early_param("intel_pstate", intel_pstate_setup);
1047
1048 MODULE_AUTHOR("Dirk Brandewie <[email protected]>");
1049 MODULE_DESCRIPTION("'intel_pstate' - P state driver Intel Core processors");
1050 MODULE_LICENSE("GPL");