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
  41 #define FRAC_BITS 8
  42 #define int_tofp(X) ((int64_t)(X) << FRAC_BITS)
  43 #define fp_toint(X) ((X) >> FRAC_BITS)
  44
  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         int freq;
  61         ktime_t time;
  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         int min;
  73         int max;
  74         int turbo;
  75         int32_t ratio;
  76 };
  77
  78 struct _pid {
  79         int setpoint;
  80         int32_t integral;
  81         int32_t p_gain;
  82         int32_t i_gain;
  83         int32_t d_gain;
  84         int deadband;
  85         int32_t last_err;
  86 };
  87
  88 struct cpudata {
  89         int cpu;
  90
  91         struct timer_list timer;
  92
  93         struct pstate_data pstate;
  94         struct vid_data vid;
  95         struct _pid pid;
  96
  97         ktime_t last_sample_time;
  98         u64     prev_aperf;
  99         u64     prev_mperf;
 100         struct sample sample;
 101 };
 102
 103 static struct cpudata **all_cpu_data;
 104 struct pstate_adjust_policy {
 105         int sample_rate_ms;
 106         int deadband;
 107         int setpoint;
 108         int p_gain_pct;
 109         int d_gain_pct;
 110         int i_gain_pct;
 111 };
 112
 113 struct pstate_funcs {
 114         int (*get_max)(void);
 115         int (*get_min)(void);
 116         int (*get_turbo)(void);
 117         void (*set)(struct cpudata*, int pstate);
 118         void (*get_vid)(struct cpudata *);
 119 };
 120
 121 struct cpu_defaults {
 122         struct pstate_adjust_policy pid_policy;
 123         struct pstate_funcs funcs;
 124 };
 125
 126 static struct pstate_adjust_policy pid_params;
 127 static struct pstate_funcs pstate_funcs;
 128
 129 struct perf_limits {
 130         int no_turbo;
 131         int turbo_disabled;
 132         int max_perf_pct;
 133         int min_perf_pct;
 134         int32_t max_perf;
 135         int32_t min_perf;
 136         int max_policy_pct;
 137         int max_sysfs_pct;
 138 };
 139
 140 static struct perf_limits limits = {
 141         .no_turbo = 0,
 142         .max_perf_pct = 100,
 143         .max_perf = int_tofp(1),
 144         .min_perf_pct = 0,
 145         .min_perf = 0,
 146         .max_policy_pct = 100,
 147         .max_sysfs_pct = 100,
 148 };
 149
 150 static inline void pid_reset(struct _pid *pid, int setpoint, int busy,
 151                         int deadband, int integral) {
 152         pid->setpoint = setpoint;
 153         pid->deadband  = deadband;
 154         pid->integral  = int_tofp(integral);
 155         pid->last_err  = int_tofp(setpoint) - int_tofp(busy);
 156 }
 157
 158 static inline void pid_p_gain_set(struct _pid *pid, int percent)
 159 {
 160         pid->p_gain = div_fp(int_tofp(percent), int_tofp(100));
 161 }
 162
 163 static inline void pid_i_gain_set(struct _pid *pid, int percent)
 164 {
 165         pid->i_gain = div_fp(int_tofp(percent), int_tofp(100));
 166 }
 167
 168 static inline void pid_d_gain_set(struct _pid *pid, int percent)
 169 {
 170
 171         pid->d_gain = div_fp(int_tofp(percent), int_tofp(100));
 172 }
 173
 174 static signed int pid_calc(struct _pid *pid, int32_t busy)
 175 {
 176         signed int result;
 177         int32_t pterm, dterm, fp_error;
 178         int32_t integral_limit;
 179
 180         fp_error = int_tofp(pid->setpoint) - busy;
 181
 182         if (abs(fp_error) <= int_tofp(pid->deadband))
 183                 return 0;
 184
 185         pterm = mul_fp(pid->p_gain, fp_error);
 186
 187         pid->integral += fp_error;
 188
 189         /* limit the integral term */
 190         integral_limit = int_tofp(30);
 191         if (pid->integral > integral_limit)
 192                 pid->integral = integral_limit;
 193         if (pid->integral < -integral_limit)
 194                 pid->integral = -integral_limit;
 195
 196         dterm = mul_fp(pid->d_gain, fp_error - pid->last_err);
 197         pid->last_err = fp_error;
 198
 199         result = pterm + mul_fp(pid->integral, pid->i_gain) + dterm;
 200         result = result + (1 << (FRAC_BITS-1));
 201         return (signed int)fp_toint(result);
 202 }
 203
 204 static inline void intel_pstate_busy_pid_reset(struct cpudata *cpu)
 205 {
 206         pid_p_gain_set(&cpu->pid, pid_params.p_gain_pct);
 207         pid_d_gain_set(&cpu->pid, pid_params.d_gain_pct);
 208         pid_i_gain_set(&cpu->pid, pid_params.i_gain_pct);
 209
 210         pid_reset(&cpu->pid,
 211                 pid_params.setpoint,
 212                 100,
 213                 pid_params.deadband,
 214                 0);
 215 }
 216
 217 static inline void intel_pstate_reset_all_pid(void)
 218 {
 219         unsigned int cpu;
 220         for_each_online_cpu(cpu) {
 221                 if (all_cpu_data[cpu])
 222                         intel_pstate_busy_pid_reset(all_cpu_data[cpu]);
 223         }
 224 }
 225
 226 /************************** debugfs begin ************************/
 227 static int pid_param_set(void *data, u64 val)
 228 {
 229         *(u32 *)data = val;
 230         intel_pstate_reset_all_pid();
 231         return 0;
 232 }
 233 static int pid_param_get(void *data, u64 *val)
 234 {
 235         *val = *(u32 *)data;
 236         return 0;
 237 }
 238 DEFINE_SIMPLE_ATTRIBUTE(fops_pid_param, pid_param_get,
 239                         pid_param_set, "%llu\n");
 240
 241 struct pid_param {
 242         char *name;
 243         void *value;
 244 };
 245
 246 static struct pid_param pid_files[] = {
 247         {"sample_rate_ms", &pid_params.sample_rate_ms},
 248         {"d_gain_pct", &pid_params.d_gain_pct},
 249         {"i_gain_pct", &pid_params.i_gain_pct},
 250         {"deadband", &pid_params.deadband},
 251         {"setpoint", &pid_params.setpoint},
 252         {"p_gain_pct", &pid_params.p_gain_pct},
 253         {NULL, NULL}
 254 };
 255
 256 static struct dentry *debugfs_parent;
 257 static void intel_pstate_debug_expose_params(void)
 258 {
 259         int i = 0;
 260
 261         debugfs_parent = debugfs_create_dir("pstate_snb", NULL);
 262         if (IS_ERR_OR_NULL(debugfs_parent))
 263                 return;
 264         while (pid_files[i].name) {
 265                 debugfs_create_file(pid_files[i].name, 0660,
 266                                 debugfs_parent, pid_files[i].value,
 267                                 &fops_pid_param);
 268                 i++;
 269         }
 270 }
 271
 272 /************************** debugfs end ************************/
 273
 274 /************************** sysfs begin ************************/
 275 #define show_one(file_name, object)                                     \
 276         static ssize_t show_##file_name                                 \
 277         (struct kobject *kobj, struct attribute *attr, char *buf)       \
 278         {                                                               \
 279                 return sprintf(buf, "%u\n", limits.object);             \
 280         }
 281
 282 static ssize_t store_no_turbo(struct kobject *a, struct attribute *b,
 283                                 const char *buf, size_t count)
 284 {
 285         unsigned int input;
 286         int ret;
 287         ret = sscanf(buf, "%u", &input);
 288         if (ret != 1)
 289                 return -EINVAL;
 290         limits.no_turbo = clamp_t(int, input, 0 , 1);
 291         if (limits.turbo_disabled) {
 292                 pr_warn("Turbo disabled by BIOS or unavailable on processor\n");
 293                 limits.no_turbo = limits.turbo_disabled;
 294         }
 295         return count;
 296 }
 297
 298 static ssize_t store_max_perf_pct(struct kobject *a, struct attribute *b,
 299                                 const char *buf, size_t count)
 300 {
 301         unsigned int input;
 302         int ret;
 303         ret = sscanf(buf, "%u", &input);
 304         if (ret != 1)
 305                 return -EINVAL;
 306
 307         limits.max_sysfs_pct = clamp_t(int, input, 0 , 100);
 308         limits.max_perf_pct = min(limits.max_policy_pct, limits.max_sysfs_pct);
 309         limits.max_perf = div_fp(int_tofp(limits.max_perf_pct), int_tofp(100));
 310         return count;
 311 }
 312
 313 static ssize_t store_min_perf_pct(struct kobject *a, struct attribute *b,
 314                                 const char *buf, size_t count)
 315 {
 316         unsigned int input;
 317         int ret;
 318         ret = sscanf(buf, "%u", &input);
 319         if (ret != 1)
 320                 return -EINVAL;
 321         limits.min_perf_pct = clamp_t(int, input, 0 , 100);
 322         limits.min_perf = div_fp(int_tofp(limits.min_perf_pct), int_tofp(100));
 323
 324         return count;
 325 }
 326
 327 show_one(no_turbo, no_turbo);
 328 show_one(max_perf_pct, max_perf_pct);
 329 show_one(min_perf_pct, min_perf_pct);
 330
 331 define_one_global_rw(no_turbo);
 332 define_one_global_rw(max_perf_pct);
 333 define_one_global_rw(min_perf_pct);
 334
 335 static struct attribute *intel_pstate_attributes[] = {
 336         &no_turbo.attr,
 337         &max_perf_pct.attr,
 338         &min_perf_pct.attr,
 339         NULL
 340 };
 341
 342 static struct attribute_group intel_pstate_attr_group = {
 343         .attrs = intel_pstate_attributes,
 344 };
 345 static struct kobject *intel_pstate_kobject;
 346
 347 static void intel_pstate_sysfs_expose_params(void)
 348 {
 349         int rc;
 350
 351         intel_pstate_kobject = kobject_create_and_add("intel_pstate",
 352                                                 &cpu_subsys.dev_root->kobj);
 353         BUG_ON(!intel_pstate_kobject);
 354         rc = sysfs_create_group(intel_pstate_kobject,
 355                                 &intel_pstate_attr_group);
 356         BUG_ON(rc);
 357 }
 358
 359 /************************** sysfs end ************************/
 360 static int byt_get_min_pstate(void)
 361 {
 362         u64 value;
 363         rdmsrl(BYT_RATIOS, value);
 364         return (value >> 8) & 0x7F;
 365 }
 366
 367 static int byt_get_max_pstate(void)
 368 {
 369         u64 value;
 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         rdmsrl(BYT_TURBO_RATIOS, value);
 378         return value & 0x7F;
 379 }
 380
 381 static void byt_set_pstate(struct cpudata *cpudata, int pstate)
 382 {
 383         u64 val;
 384         int32_t vid_fp;
 385         u32 vid;
 386
 387         val = pstate << 8;
 388         if (limits.no_turbo && !limits.turbo_disabled)
 389                 val |= (u64)1 << 32;
 390
 391         vid_fp = cpudata->vid.min + mul_fp(
 392                 int_tofp(pstate - cpudata->pstate.min_pstate),
 393                 cpudata->vid.ratio);
 394
 395         vid_fp = clamp_t(int32_t, vid_fp, cpudata->vid.min, cpudata->vid.max);
 396         vid = fp_toint(vid_fp);
 397
 398         if (pstate > cpudata->pstate.max_pstate)
 399                 vid = cpudata->vid.turbo;
 400
 401         val |= vid;
 402
 403         wrmsrl(MSR_IA32_PERF_CTL, val);
 404 }
 405
 406 static void byt_get_vid(struct cpudata *cpudata)
 407 {
 408         u64 value;
 409
 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
 424 static int core_get_min_pstate(void)
 425 {
 426         u64 value;
 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         rdmsrl(MSR_PLATFORM_INFO, value);
 435         return (value >> 8) & 0xFF;
 436 }
 437
 438 static int core_get_turbo_pstate(void)
 439 {
 440         u64 value;
 441         int nont, ret;
 442         rdmsrl(MSR_NHM_TURBO_RATIO_LIMIT, value);
 443         nont = core_get_max_pstate();
 444         ret = ((value) & 255);
 445         if (ret <= nont)
 446                 ret = nont;
 447         return ret;
 448 }
 449
 450 static void core_set_pstate(struct cpudata *cpudata, int pstate)
 451 {
 452         u64 val;
 453
 454         val = pstate << 8;
 455         if (limits.no_turbo && !limits.turbo_disabled)
 456                 val |= (u64)1 << 32;
 457
 458         wrmsrl_on_cpu(cpudata->cpu, MSR_IA32_PERF_CTL, val);
 459 }
 460
 461 static struct cpu_defaults core_params = {
 462         .pid_policy = {
 463                 .sample_rate_ms = 10,
 464                 .deadband = 0,
 465                 .setpoint = 97,
 466                 .p_gain_pct = 20,
 467                 .d_gain_pct = 0,
 468                 .i_gain_pct = 0,
 469         },
 470         .funcs = {
 471                 .get_max = core_get_max_pstate,
 472                 .get_min = core_get_min_pstate,
 473                 .get_turbo = core_get_turbo_pstate,
 474                 .set = core_set_pstate,
 475         },
 476 };
 477
 478 static struct cpu_defaults byt_params = {
 479         .pid_policy = {
 480                 .sample_rate_ms = 10,
 481                 .deadband = 0,
 482                 .setpoint = 97,
 483                 .p_gain_pct = 14,
 484                 .d_gain_pct = 0,
 485                 .i_gain_pct = 4,
 486         },
 487         .funcs = {
 488                 .get_max = byt_get_max_pstate,
 489                 .get_min = byt_get_min_pstate,
 490                 .get_turbo = byt_get_turbo_pstate,
 491                 .set = byt_set_pstate,
 492                 .get_vid = byt_get_vid,
 493         },
 494 };
 495
 496
 497 static void intel_pstate_get_min_max(struct cpudata *cpu, int *min, int *max)
 498 {
 499         int max_perf = cpu->pstate.turbo_pstate;
 500         int max_perf_adj;
 501         int min_perf;
 502         if (limits.no_turbo)
 503                 max_perf = cpu->pstate.max_pstate;
 504
 505         max_perf_adj = fp_toint(mul_fp(int_tofp(max_perf), limits.max_perf));
 506         *max = clamp_t(int, max_perf_adj,
 507                         cpu->pstate.min_pstate, cpu->pstate.turbo_pstate);
 508
 509         min_perf = fp_toint(mul_fp(int_tofp(max_perf), limits.min_perf));
 510         *min = clamp_t(int, min_perf,
 511                         cpu->pstate.min_pstate, max_perf);
 512 }
 513
 514 static void intel_pstate_set_pstate(struct cpudata *cpu, int pstate)
 515 {
 516         int max_perf, min_perf;
 517
 518         intel_pstate_get_min_max(cpu, &min_perf, &max_perf);
 519
 520         pstate = clamp_t(int, pstate, min_perf, max_perf);
 521
 522         if (pstate == cpu->pstate.current_pstate)
 523                 return;
 524
 525         trace_cpu_frequency(pstate * 100000, cpu->cpu);
 526
 527         cpu->pstate.current_pstate = pstate;
 528
 529         pstate_funcs.set(cpu, pstate);
 530 }
 531
 532 static inline void intel_pstate_pstate_increase(struct cpudata *cpu, int steps)
 533 {
 534         int target;
 535         target = cpu->pstate.current_pstate + steps;
 536
 537         intel_pstate_set_pstate(cpu, target);
 538 }
 539
 540 static inline void intel_pstate_pstate_decrease(struct cpudata *cpu, int steps)
 541 {
 542         int target;
 543         target = cpu->pstate.current_pstate - steps;
 544         intel_pstate_set_pstate(cpu, target);
 545 }
 546
 547 static void intel_pstate_get_cpu_pstates(struct cpudata *cpu)
 548 {
 549         cpu->pstate.min_pstate = pstate_funcs.get_min();
 550         cpu->pstate.max_pstate = pstate_funcs.get_max();
 551         cpu->pstate.turbo_pstate = pstate_funcs.get_turbo();
 552
 553         if (pstate_funcs.get_vid)
 554                 pstate_funcs.get_vid(cpu);
 555         intel_pstate_set_pstate(cpu, cpu->pstate.min_pstate);
 556 }
 557
 558 static inline void intel_pstate_calc_busy(struct cpudata *cpu)
 559 {
 560         struct sample *sample = &cpu->sample;
 561         int64_t core_pct;
 562         int32_t rem;
 563
 564         core_pct = int_tofp(sample->aperf) * int_tofp(100);
 565         core_pct = div_u64_rem(core_pct, int_tofp(sample->mperf), &rem);
 566
 567         if ((rem << 1) >= int_tofp(sample->mperf))
 568                 core_pct += 1;
 569
 570         sample->freq = fp_toint(
 571                 mul_fp(int_tofp(cpu->pstate.max_pstate * 1000), core_pct));
 572
 573         sample->core_pct_busy = (int32_t)core_pct;
 574 }
 575
 576 static inline void intel_pstate_sample(struct cpudata *cpu)
 577 {
 578         u64 aperf, mperf;
 579
 580         rdmsrl(MSR_IA32_APERF, aperf);
 581         rdmsrl(MSR_IA32_MPERF, mperf);
 582
 583         aperf = aperf >> FRAC_BITS;
 584         mperf = mperf >> FRAC_BITS;
 585
 586         cpu->last_sample_time = cpu->sample.time;
 587         cpu->sample.time = ktime_get();
 588         cpu->sample.aperf = aperf;
 589         cpu->sample.mperf = mperf;
 590         cpu->sample.aperf -= cpu->prev_aperf;
 591         cpu->sample.mperf -= cpu->prev_mperf;
 592
 593         intel_pstate_calc_busy(cpu);
 594
 595         cpu->prev_aperf = aperf;
 596         cpu->prev_mperf = mperf;
 597 }
 598
 599 static inline void intel_pstate_set_sample_time(struct cpudata *cpu)
 600 {
 601         int sample_time, delay;
 602
 603         sample_time = pid_params.sample_rate_ms;
 604         delay = msecs_to_jiffies(sample_time);
 605         mod_timer_pinned(&cpu->timer, jiffies + delay);
 606 }
 607
 608 static inline int32_t intel_pstate_get_scaled_busy(struct cpudata *cpu)
 609 {
 610         int32_t core_busy, max_pstate, current_pstate, sample_ratio;
 611         u32 duration_us;
 612         u32 sample_time;
 613
 614         core_busy = cpu->sample.core_pct_busy;
 615         max_pstate = int_tofp(cpu->pstate.max_pstate);
 616         current_pstate = int_tofp(cpu->pstate.current_pstate);
 617         core_busy = mul_fp(core_busy, div_fp(max_pstate, current_pstate));
 618
 619         sample_time = (pid_params.sample_rate_ms  * USEC_PER_MSEC);
 620         duration_us = (u32) ktime_us_delta(cpu->sample.time,
 621                                         cpu->last_sample_time);
 622         if (duration_us > sample_time * 3) {
 623                 sample_ratio = div_fp(int_tofp(sample_time),
 624                                 int_tofp(duration_us));
 625                 core_busy = mul_fp(core_busy, sample_ratio);
 626         }
 627
 628         return core_busy;
 629 }
 630
 631 static inline void intel_pstate_adjust_busy_pstate(struct cpudata *cpu)
 632 {
 633         int32_t busy_scaled;
 634         struct _pid *pid;
 635         signed int ctl = 0;
 636         int steps;
 637
 638         pid = &cpu->pid;
 639         busy_scaled = intel_pstate_get_scaled_busy(cpu);
 640
 641         ctl = pid_calc(pid, busy_scaled);
 642
 643         steps = abs(ctl);
 644
 645         if (ctl < 0)
 646                 intel_pstate_pstate_increase(cpu, steps);
 647         else
 648                 intel_pstate_pstate_decrease(cpu, steps);
 649 }
 650
 651 static void intel_pstate_timer_func(unsigned long __data)
 652 {
 653         struct cpudata *cpu = (struct cpudata *) __data;
 654         struct sample *sample;
 655
 656         intel_pstate_sample(cpu);
 657
 658         sample = &cpu->sample;
 659
 660         intel_pstate_adjust_busy_pstate(cpu);
 661
 662         trace_pstate_sample(fp_toint(sample->core_pct_busy),
 663                         fp_toint(intel_pstate_get_scaled_busy(cpu)),
 664                         cpu->pstate.current_pstate,
 665                         sample->mperf,
 666                         sample->aperf,
 667                         sample->freq);
 668
 669         intel_pstate_set_sample_time(cpu);
 670 }
 671
 672 #define ICPU(model, policy) \
 673         { X86_VENDOR_INTEL, 6, model, X86_FEATURE_APERFMPERF,\
 674                         (unsigned long)&policy }
 675
 676 static const struct x86_cpu_id intel_pstate_cpu_ids[] = {
 677         ICPU(0x2a, core_params),
 678         ICPU(0x2d, core_params),
 679         ICPU(0x37, byt_params),
 680         ICPU(0x3a, core_params),
 681         ICPU(0x3c, core_params),
 682         ICPU(0x3d, core_params),
 683         ICPU(0x3e, core_params),
 684         ICPU(0x3f, core_params),
 685         ICPU(0x45, core_params),
 686         ICPU(0x46, core_params),
 687         ICPU(0x4f, core_params),
 688         ICPU(0x56, core_params),
 689         {}
 690 };
 691 MODULE_DEVICE_TABLE(x86cpu, intel_pstate_cpu_ids);
 692
 693 static int intel_pstate_init_cpu(unsigned int cpunum)
 694 {
 695         struct cpudata *cpu;
 696
 697         all_cpu_data[cpunum] = kzalloc(sizeof(struct cpudata), GFP_KERNEL);
 698         if (!all_cpu_data[cpunum])
 699                 return -ENOMEM;
 700
 701         cpu = all_cpu_data[cpunum];
 702
 703         cpu->cpu = cpunum;
 704         intel_pstate_get_cpu_pstates(cpu);
 705
 706         init_timer_deferrable(&cpu->timer);
 707         cpu->timer.function = intel_pstate_timer_func;
 708         cpu->timer.data =
 709                 (unsigned long)cpu;
 710         cpu->timer.expires = jiffies + HZ/100;
 711         intel_pstate_busy_pid_reset(cpu);
 712         intel_pstate_sample(cpu);
 713
 714         add_timer_on(&cpu->timer, cpunum);
 715
 716         pr_info("Intel pstate controlling: cpu %d\n", cpunum);
 717
 718         return 0;
 719 }
 720
 721 static unsigned int intel_pstate_get(unsigned int cpu_num)
 722 {
 723         struct sample *sample;
 724         struct cpudata *cpu;
 725
 726         cpu = all_cpu_data[cpu_num];
 727         if (!cpu)
 728                 return 0;
 729         sample = &cpu->sample;
 730         return sample->freq;
 731 }
 732
 733 static int intel_pstate_set_policy(struct cpufreq_policy *policy)
 734 {
 735         struct cpudata *cpu;
 736
 737         cpu = all_cpu_data[policy->cpu];
 738
 739         if (!policy->cpuinfo.max_freq)
 740                 return -ENODEV;
 741
 742         if (policy->policy == CPUFREQ_POLICY_PERFORMANCE) {
 743                 limits.min_perf_pct = 100;
 744                 limits.min_perf = int_tofp(1);
 745                 limits.max_perf_pct = 100;
 746                 limits.max_perf = int_tofp(1);
 747                 limits.no_turbo = limits.turbo_disabled;
 748                 return 0;
 749         }
 750         limits.min_perf_pct = (policy->min * 100) / policy->cpuinfo.max_freq;
 751         limits.min_perf_pct = clamp_t(int, limits.min_perf_pct, 0 , 100);
 752         limits.min_perf = div_fp(int_tofp(limits.min_perf_pct), int_tofp(100));
 753
 754         limits.max_policy_pct = policy->max * 100 / policy->cpuinfo.max_freq;
 755         limits.max_policy_pct = clamp_t(int, limits.max_policy_pct, 0 , 100);
 756         limits.max_perf_pct = min(limits.max_policy_pct, limits.max_sysfs_pct);
 757         limits.max_perf = div_fp(int_tofp(limits.max_perf_pct), int_tofp(100));
 758
 759         return 0;
 760 }
 761
 762 static int intel_pstate_verify_policy(struct cpufreq_policy *policy)
 763 {
 764         cpufreq_verify_within_cpu_limits(policy);
 765
 766         if ((policy->policy != CPUFREQ_POLICY_POWERSAVE) &&
 767                 (policy->policy != CPUFREQ_POLICY_PERFORMANCE))
 768                 return -EINVAL;
 769
 770         return 0;
 771 }
 772
 773 static void intel_pstate_stop_cpu(struct cpufreq_policy *policy)
 774 {
 775         int cpu_num = policy->cpu;
 776         struct cpudata *cpu = all_cpu_data[cpu_num];
 777
 778         pr_info("intel_pstate CPU %d exiting\n", cpu_num);
 779
 780         del_timer_sync(&all_cpu_data[cpu_num]->timer);
 781         intel_pstate_set_pstate(cpu, cpu->pstate.min_pstate);
 782         kfree(all_cpu_data[cpu_num]);
 783         all_cpu_data[cpu_num] = NULL;
 784 }
 785
 786 static int intel_pstate_cpu_init(struct cpufreq_policy *policy)
 787 {
 788         struct cpudata *cpu;
 789         int rc;
 790         u64 misc_en;
 791
 792         rc = intel_pstate_init_cpu(policy->cpu);
 793         if (rc)
 794                 return rc;
 795
 796         cpu = all_cpu_data[policy->cpu];
 797
 798         rdmsrl(MSR_IA32_MISC_ENABLE, misc_en);
 799         if (misc_en & MSR_IA32_MISC_ENABLE_TURBO_DISABLE ||
 800                 cpu->pstate.max_pstate == cpu->pstate.turbo_pstate) {
 801                 limits.turbo_disabled = 1;
 802                 limits.no_turbo = 1;
 803         }
 804         if (limits.min_perf_pct == 100 && limits.max_perf_pct == 100)
 805                 policy->policy = CPUFREQ_POLICY_PERFORMANCE;
 806         else
 807                 policy->policy = CPUFREQ_POLICY_POWERSAVE;
 808
 809         policy->min = cpu->pstate.min_pstate * 100000;
 810         policy->max = cpu->pstate.turbo_pstate * 100000;
 811
 812         /* cpuinfo and default policy values */
 813         policy->cpuinfo.min_freq = cpu->pstate.min_pstate * 100000;
 814         policy->cpuinfo.max_freq = cpu->pstate.turbo_pstate * 100000;
 815         policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
 816         cpumask_set_cpu(policy->cpu, policy->cpus);
 817
 818         return 0;
 819 }
 820
 821 static struct cpufreq_driver intel_pstate_driver = {
 822         .flags          = CPUFREQ_CONST_LOOPS,
 823         .verify         = intel_pstate_verify_policy,
 824         .setpolicy      = intel_pstate_set_policy,
 825         .get            = intel_pstate_get,
 826         .init           = intel_pstate_cpu_init,
 827         .stop_cpu       = intel_pstate_stop_cpu,
 828         .name           = "intel_pstate",
 829 };
 830
 831 static int __initdata no_load;
 832
 833 static int intel_pstate_msrs_not_valid(void)
 834 {
 835         /* Check that all the msr's we are using are valid. */
 836         u64 aperf, mperf, tmp;
 837
 838         rdmsrl(MSR_IA32_APERF, aperf);
 839         rdmsrl(MSR_IA32_MPERF, mperf);
 840
 841         if (!pstate_funcs.get_max() ||
 842                 !pstate_funcs.get_min() ||
 843                 !pstate_funcs.get_turbo())
 844                 return -ENODEV;
 845
 846         rdmsrl(MSR_IA32_APERF, tmp);
 847         if (!(tmp - aperf))
 848                 return -ENODEV;
 849
 850         rdmsrl(MSR_IA32_MPERF, tmp);
 851         if (!(tmp - mperf))
 852                 return -ENODEV;
 853
 854         return 0;
 855 }
 856
 857 static void copy_pid_params(struct pstate_adjust_policy *policy)
 858 {
 859         pid_params.sample_rate_ms = policy->sample_rate_ms;
 860         pid_params.p_gain_pct = policy->p_gain_pct;
 861         pid_params.i_gain_pct = policy->i_gain_pct;
 862         pid_params.d_gain_pct = policy->d_gain_pct;
 863         pid_params.deadband = policy->deadband;
 864         pid_params.setpoint = policy->setpoint;
 865 }
 866
 867 static void copy_cpu_funcs(struct pstate_funcs *funcs)
 868 {
 869         pstate_funcs.get_max   = funcs->get_max;
 870         pstate_funcs.get_min   = funcs->get_min;
 871         pstate_funcs.get_turbo = funcs->get_turbo;
 872         pstate_funcs.set       = funcs->set;
 873         pstate_funcs.get_vid   = funcs->get_vid;
 874 }
 875
 876 #if IS_ENABLED(CONFIG_ACPI)
 877 #include <acpi/processor.h>
 878
 879 static bool intel_pstate_no_acpi_pss(void)
 880 {
 881         int i;
 882
 883         for_each_possible_cpu(i) {
 884                 acpi_status status;
 885                 union acpi_object *pss;
 886                 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 887                 struct acpi_processor *pr = per_cpu(processors, i);
 888
 889                 if (!pr)
 890                         continue;
 891
 892                 status = acpi_evaluate_object(pr->handle, "_PSS", NULL, &buffer);
 893                 if (ACPI_FAILURE(status))
 894                         continue;
 895
 896                 pss = buffer.pointer;
 897                 if (pss && pss->type == ACPI_TYPE_PACKAGE) {
 898                         kfree(pss);
 899                         return false;
 900                 }
 901
 902                 kfree(pss);
 903         }
 904
 905         return true;
 906 }
 907
 908 struct hw_vendor_info {
 909         u16  valid;
 910         char oem_id[ACPI_OEM_ID_SIZE];
 911         char oem_table_id[ACPI_OEM_TABLE_ID_SIZE];
 912 };
 913
 914 /* Hardware vendor-specific info that has its own power management modes */
 915 static struct hw_vendor_info vendor_info[] = {
 916         {1, "HP    ", "ProLiant"},
 917         {0, "", ""},
 918 };
 919
 920 static bool intel_pstate_platform_pwr_mgmt_exists(void)
 921 {
 922         struct acpi_table_header hdr;
 923         struct hw_vendor_info *v_info;
 924
 925         if (acpi_disabled
 926             || ACPI_FAILURE(acpi_get_table_header(ACPI_SIG_FADT, 0, &hdr)))
 927                 return false;
 928
 929         for (v_info = vendor_info; v_info->valid; v_info++) {
 930                 if (!strncmp(hdr.oem_id, v_info->oem_id, ACPI_OEM_ID_SIZE)
 931                     && !strncmp(hdr.oem_table_id, v_info->oem_table_id, ACPI_OEM_TABLE_ID_SIZE)
 932                     && intel_pstate_no_acpi_pss())
 933                         return true;
 934         }
 935
 936         return false;
 937 }
 938 #else /* CONFIG_ACPI not enabled */
 939 static inline bool intel_pstate_platform_pwr_mgmt_exists(void) { return false; }
 940 #endif /* CONFIG_ACPI */
 941
 942 static int __init intel_pstate_init(void)
 943 {
 944         int cpu, rc = 0;
 945         const struct x86_cpu_id *id;
 946         struct cpu_defaults *cpu_info;
 947
 948         if (no_load)
 949                 return -ENODEV;
 950
 951         id = x86_match_cpu(intel_pstate_cpu_ids);
 952         if (!id)
 953                 return -ENODEV;
 954
 955         /*
 956          * The Intel pstate driver will be ignored if the platform
 957          * firmware has its own power management modes.
 958          */
 959         if (intel_pstate_platform_pwr_mgmt_exists())
 960                 return -ENODEV;
 961
 962         cpu_info = (struct cpu_defaults *)id->driver_data;
 963
 964         copy_pid_params(&cpu_info->pid_policy);
 965         copy_cpu_funcs(&cpu_info->funcs);
 966
 967         if (intel_pstate_msrs_not_valid())
 968                 return -ENODEV;
 969
 970         pr_info("Intel P-state driver initializing.\n");
 971
 972         all_cpu_data = vzalloc(sizeof(void *) * num_possible_cpus());
 973         if (!all_cpu_data)
 974                 return -ENOMEM;
 975
 976         rc = cpufreq_register_driver(&intel_pstate_driver);
 977         if (rc)
 978                 goto out;
 979
 980         intel_pstate_debug_expose_params();
 981         intel_pstate_sysfs_expose_params();
 982
 983         return rc;
 984 out:
 985         get_online_cpus();
 986         for_each_online_cpu(cpu) {
 987                 if (all_cpu_data[cpu]) {
 988                         del_timer_sync(&all_cpu_data[cpu]->timer);
 989                         kfree(all_cpu_data[cpu]);
 990                 }
 991         }
 992
 993         put_online_cpus();
 994         vfree(all_cpu_data);
 995         return -ENODEV;
 996 }
 997 device_initcall(intel_pstate_init);
 998
 999 static int __init intel_pstate_setup(char *str)
1000 {
1001         if (!str)
1002                 return -EINVAL;
1003
1004         if (!strcmp(str, "disable"))
1005                 no_load = 1;
1006         return 0;
1007 }
1008 early_param("intel_pstate", intel_pstate_setup);
1009
1010 MODULE_AUTHOR("Dirk Brandewie <dirk.j.brandewie@intel.com>");
1011 MODULE_DESCRIPTION("'intel_pstate' - P state driver Intel Core processors");
1012 MODULE_LICENSE("GPL");