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 <linux/vmalloc.h>
  30 #include <trace/events/power.h>
  31
  32 #include <asm/div64.h>
  33 #include <asm/msr.h>
  34 #include <asm/cpu_device_id.h>
  35 #include <asm/cpufeature.h>
  36
  37 #define ATOM_RATIOS             0x66a
  38 #define ATOM_VIDS               0x66b
  39 #define ATOM_TURBO_RATIOS       0x66c
  40 #define ATOM_TURBO_VIDS         0x66d
  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(s64 x, s64 y)
  52 {
  53         return div64_s64((int64_t)x << FRAC_BITS, y);
  54 }
  55
  56 static inline int ceiling_fp(int32_t x)
  57 {
  58         int mask, ret;
  59
  60         ret = fp_toint(x);
  61         mask = (1 << FRAC_BITS) - 1;
  62         if (x & mask)
  63                 ret += 1;
  64         return ret;
  65 }
  66
  67 /**
  68  * struct sample -      Store performance sample
  69  * @core_pct_busy:      Ratio of APERF/MPERF in percent, which is actual
  70  *                      performance during last sample period
  71  * @busy_scaled:        Scaled busy value which is used to calculate next
  72  *                      P state. This can be different than core_pct_busy
  73  *                      to account for cpu idle period
  74  * @aperf:              Difference of actual performance frequency clock count
  75  *                      read from APERF MSR between last and current sample
  76  * @mperf:              Difference of maximum performance frequency clock count
  77  *                      read from MPERF MSR between last and current sample
  78  * @tsc:                Difference of time stamp counter between last and
  79  *                      current sample
  80  * @freq:               Effective frequency calculated from APERF/MPERF
  81  * @time:               Current time from scheduler
  82  *
  83  * This structure is used in the cpudata structure to store performance sample
  84  * data for choosing next P State.
  85  */
  86 struct sample {
  87         int32_t core_pct_busy;
  88         int32_t busy_scaled;
  89         u64 aperf;
  90         u64 mperf;
  91         u64 tsc;
  92         int freq;
  93         u64 time;
  94 };
  95
  96 /**
  97  * struct pstate_data - Store P state data
  98  * @current_pstate:     Current requested P state
  99  * @min_pstate:         Min P state possible for this platform
 100  * @max_pstate:         Max P state possible for this platform
 101  * @max_pstate_physical:This is physical Max P state for a processor
 102  *                      This can be higher than the max_pstate which can
 103  *                      be limited by platform thermal design power limits
 104  * @scaling:            Scaling factor to  convert frequency to cpufreq
 105  *                      frequency units
 106  * @turbo_pstate:       Max Turbo P state possible for this platform
 107  *
 108  * Stores the per cpu model P state limits and current P state.
 109  */
 110 struct pstate_data {
 111         int     current_pstate;
 112         int     min_pstate;
 113         int     max_pstate;
 114         int     max_pstate_physical;
 115         int     scaling;
 116         int     turbo_pstate;
 117 };
 118
 119 /**
 120  * struct vid_data -    Stores voltage information data
 121  * @min:                VID data for this platform corresponding to
 122  *                      the lowest P state
 123  * @max:                VID data corresponding to the highest P State.
 124  * @turbo:              VID data for turbo P state
 125  * @ratio:              Ratio of (vid max - vid min) /
 126  *                      (max P state - Min P State)
 127  *
 128  * Stores the voltage data for DVFS (Dynamic Voltage and Frequency Scaling)
 129  * This data is used in Atom platforms, where in addition to target P state,
 130  * the voltage data needs to be specified to select next P State.
 131  */
 132 struct vid_data {
 133         int min;
 134         int max;
 135         int turbo;
 136         int32_t ratio;
 137 };
 138
 139 /**
 140  * struct _pid -        Stores PID data
 141  * @setpoint:           Target set point for busyness or performance
 142  * @integral:           Storage for accumulated error values
 143  * @p_gain:             PID proportional gain
 144  * @i_gain:             PID integral gain
 145  * @d_gain:             PID derivative gain
 146  * @deadband:           PID deadband
 147  * @last_err:           Last error storage for integral part of PID calculation
 148  *
 149  * Stores PID coefficients and last error for PID controller.
 150  */
 151 struct _pid {
 152         int setpoint;
 153         int32_t integral;
 154         int32_t p_gain;
 155         int32_t i_gain;
 156         int32_t d_gain;
 157         int deadband;
 158         int32_t last_err;
 159 };
 160
 161 /**
 162  * struct cpudata -     Per CPU instance data storage
 163  * @cpu:                CPU number for this instance data
 164  * @update_util:        CPUFreq utility callback information
 165  * @pstate:             Stores P state limits for this CPU
 166  * @vid:                Stores VID limits for this CPU
 167  * @pid:                Stores PID parameters for this CPU
 168  * @last_sample_time:   Last Sample time
 169  * @prev_aperf:         Last APERF value read from APERF MSR
 170  * @prev_mperf:         Last MPERF value read from MPERF MSR
 171  * @prev_tsc:           Last timestamp counter (TSC) value
 172  * @prev_cummulative_iowait: IO Wait time difference from last and
 173  *                      current sample
 174  * @sample:             Storage for storing last Sample data
 175  *
 176  * This structure stores per CPU instance data for all CPUs.
 177  */
 178 struct cpudata {
 179         int cpu;
 180
 181         struct update_util_data update_util;
 182
 183         struct pstate_data pstate;
 184         struct vid_data vid;
 185         struct _pid pid;
 186
 187         u64     last_sample_time;
 188         u64     prev_aperf;
 189         u64     prev_mperf;
 190         u64     prev_tsc;
 191         u64     prev_cummulative_iowait;
 192         struct sample sample;
 193 };
 194
 195 static struct cpudata **all_cpu_data;
 196
 197 /**
 198  * struct pid_adjust_policy - Stores static PID configuration data
 199  * @sample_rate_ms:     PID calculation sample rate in ms
 200  * @sample_rate_ns:     Sample rate calculation in ns
 201  * @deadband:           PID deadband
 202  * @setpoint:           PID Setpoint
 203  * @p_gain_pct:         PID proportional gain
 204  * @i_gain_pct:         PID integral gain
 205  * @d_gain_pct:         PID derivative gain
 206  *
 207  * Stores per CPU model static PID configuration data.
 208  */
 209 struct pstate_adjust_policy {
 210         int sample_rate_ms;
 211         s64 sample_rate_ns;
 212         int deadband;
 213         int setpoint;
 214         int p_gain_pct;
 215         int d_gain_pct;
 216         int i_gain_pct;
 217 };
 218
 219 /**
 220  * struct pstate_funcs - Per CPU model specific callbacks
 221  * @get_max:            Callback to get maximum non turbo effective P state
 222  * @get_max_physical:   Callback to get maximum non turbo physical P state
 223  * @get_min:            Callback to get minimum P state
 224  * @get_turbo:          Callback to get turbo P state
 225  * @get_scaling:        Callback to get frequency scaling factor
 226  * @get_val:            Callback to convert P state to actual MSR write value
 227  * @get_vid:            Callback to get VID data for Atom platforms
 228  * @get_target_pstate:  Callback to a function to calculate next P state to use
 229  *
 230  * Core and Atom CPU models have different way to get P State limits. This
 231  * structure is used to store those callbacks.
 232  */
 233 struct pstate_funcs {
 234         int (*get_max)(void);
 235         int (*get_max_physical)(void);
 236         int (*get_min)(void);
 237         int (*get_turbo)(void);
 238         int (*get_scaling)(void);
 239         u64 (*get_val)(struct cpudata*, int pstate);
 240         void (*get_vid)(struct cpudata *);
 241         int32_t (*get_target_pstate)(struct cpudata *);
 242 };
 243
 244 /**
 245  * struct cpu_defaults- Per CPU model default config data
 246  * @pid_policy: PID config data
 247  * @funcs:              Callback function data
 248  */
 249 struct cpu_defaults {
 250         struct pstate_adjust_policy pid_policy;
 251         struct pstate_funcs funcs;
 252 };
 253
 254 static inline int32_t get_target_pstate_use_performance(struct cpudata *cpu);
 255 static inline int32_t get_target_pstate_use_cpu_load(struct cpudata *cpu);
 256
 257 static struct pstate_adjust_policy pid_params;
 258 static struct pstate_funcs pstate_funcs;
 259 static int hwp_active;
 260
 261
 262 /**
 263  * struct perf_limits - Store user and policy limits
 264  * @no_turbo:           User requested turbo state from intel_pstate sysfs
 265  * @turbo_disabled:     Platform turbo status either from msr
 266  *                      MSR_IA32_MISC_ENABLE or when maximum available pstate
 267  *                      matches the maximum turbo pstate
 268  * @max_perf_pct:       Effective maximum performance limit in percentage, this
 269  *                      is minimum of either limits enforced by cpufreq policy
 270  *                      or limits from user set limits via intel_pstate sysfs
 271  * @min_perf_pct:       Effective minimum performance limit in percentage, this
 272  *                      is maximum of either limits enforced by cpufreq policy
 273  *                      or limits from user set limits via intel_pstate sysfs
 274  * @max_perf:           This is a scaled value between 0 to 255 for max_perf_pct
 275  *                      This value is used to limit max pstate
 276  * @min_perf:           This is a scaled value between 0 to 255 for min_perf_pct
 277  *                      This value is used to limit min pstate
 278  * @max_policy_pct:     The maximum performance in percentage enforced by
 279  *                      cpufreq setpolicy interface
 280  * @max_sysfs_pct:      The maximum performance in percentage enforced by
 281  *                      intel pstate sysfs interface
 282  * @min_policy_pct:     The minimum performance in percentage enforced by
 283  *                      cpufreq setpolicy interface
 284  * @min_sysfs_pct:      The minimum performance in percentage enforced by
 285  *                      intel pstate sysfs interface
 286  *
 287  * Storage for user and policy defined limits.
 288  */
 289 struct perf_limits {
 290         int no_turbo;
 291         int turbo_disabled;
 292         int max_perf_pct;
 293         int min_perf_pct;
 294         int32_t max_perf;
 295         int32_t min_perf;
 296         int max_policy_pct;
 297         int max_sysfs_pct;
 298         int min_policy_pct;
 299         int min_sysfs_pct;
 300 };
 301
 302 static struct perf_limits performance_limits = {
 303         .no_turbo = 0,
 304         .turbo_disabled = 0,
 305         .max_perf_pct = 100,
 306         .max_perf = int_tofp(1),
 307         .min_perf_pct = 100,
 308         .min_perf = int_tofp(1),
 309         .max_policy_pct = 100,
 310         .max_sysfs_pct = 100,
 311         .min_policy_pct = 0,
 312         .min_sysfs_pct = 0,
 313 };
 314
 315 static struct perf_limits powersave_limits = {
 316         .no_turbo = 0,
 317         .turbo_disabled = 0,
 318         .max_perf_pct = 100,
 319         .max_perf = int_tofp(1),
 320         .min_perf_pct = 0,
 321         .min_perf = 0,
 322         .max_policy_pct = 100,
 323         .max_sysfs_pct = 100,
 324         .min_policy_pct = 0,
 325         .min_sysfs_pct = 0,
 326 };
 327
 328 #ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE
 329 static struct perf_limits *limits = &performance_limits;
 330 #else
 331 static struct perf_limits *limits = &powersave_limits;
 332 #endif
 333
 334 static inline void pid_reset(struct _pid *pid, int setpoint, int busy,
 335                              int deadband, int integral) {
 336         pid->setpoint = int_tofp(setpoint);
 337         pid->deadband  = int_tofp(deadband);
 338         pid->integral  = int_tofp(integral);
 339         pid->last_err  = int_tofp(setpoint) - int_tofp(busy);
 340 }
 341
 342 static inline void pid_p_gain_set(struct _pid *pid, int percent)
 343 {
 344         pid->p_gain = div_fp(percent, 100);
 345 }
 346
 347 static inline void pid_i_gain_set(struct _pid *pid, int percent)
 348 {
 349         pid->i_gain = div_fp(percent, 100);
 350 }
 351
 352 static inline void pid_d_gain_set(struct _pid *pid, int percent)
 353 {
 354         pid->d_gain = div_fp(percent, 100);
 355 }
 356
 357 static signed int pid_calc(struct _pid *pid, int32_t busy)
 358 {
 359         signed int result;
 360         int32_t pterm, dterm, fp_error;
 361         int32_t integral_limit;
 362
 363         fp_error = pid->setpoint - busy;
 364
 365         if (abs(fp_error) <= pid->deadband)
 366                 return 0;
 367
 368         pterm = mul_fp(pid->p_gain, fp_error);
 369
 370         pid->integral += fp_error;
 371
 372         /*
 373          * We limit the integral here so that it will never
 374          * get higher than 30.  This prevents it from becoming
 375          * too large an input over long periods of time and allows
 376          * it to get factored out sooner.
 377          *
 378          * The value of 30 was chosen through experimentation.
 379          */
 380         integral_limit = int_tofp(30);
 381         if (pid->integral > integral_limit)
 382                 pid->integral = integral_limit;
 383         if (pid->integral < -integral_limit)
 384                 pid->integral = -integral_limit;
 385
 386         dterm = mul_fp(pid->d_gain, fp_error - pid->last_err);
 387         pid->last_err = fp_error;
 388
 389         result = pterm + mul_fp(pid->integral, pid->i_gain) + dterm;
 390         result = result + (1 << (FRAC_BITS-1));
 391         return (signed int)fp_toint(result);
 392 }
 393
 394 static inline void intel_pstate_busy_pid_reset(struct cpudata *cpu)
 395 {
 396         pid_p_gain_set(&cpu->pid, pid_params.p_gain_pct);
 397         pid_d_gain_set(&cpu->pid, pid_params.d_gain_pct);
 398         pid_i_gain_set(&cpu->pid, pid_params.i_gain_pct);
 399
 400         pid_reset(&cpu->pid, pid_params.setpoint, 100, pid_params.deadband, 0);
 401 }
 402
 403 static inline void intel_pstate_reset_all_pid(void)
 404 {
 405         unsigned int cpu;
 406
 407         for_each_online_cpu(cpu) {
 408                 if (all_cpu_data[cpu])
 409                         intel_pstate_busy_pid_reset(all_cpu_data[cpu]);
 410         }
 411 }
 412
 413 static inline void update_turbo_state(void)
 414 {
 415         u64 misc_en;
 416         struct cpudata *cpu;
 417
 418         cpu = all_cpu_data[0];
 419         rdmsrl(MSR_IA32_MISC_ENABLE, misc_en);
 420         limits->turbo_disabled =
 421                 (misc_en & MSR_IA32_MISC_ENABLE_TURBO_DISABLE ||
 422                  cpu->pstate.max_pstate == cpu->pstate.turbo_pstate);
 423 }
 424
 425 static void intel_pstate_hwp_set(const struct cpumask *cpumask)
 426 {
 427         int min, hw_min, max, hw_max, cpu, range, adj_range;
 428         u64 value, cap;
 429
 430         rdmsrl(MSR_HWP_CAPABILITIES, cap);
 431         hw_min = HWP_LOWEST_PERF(cap);
 432         hw_max = HWP_HIGHEST_PERF(cap);
 433         range = hw_max - hw_min;
 434
 435         for_each_cpu(cpu, cpumask) {
 436                 rdmsrl_on_cpu(cpu, MSR_HWP_REQUEST, &value);
 437                 adj_range = limits->min_perf_pct * range / 100;
 438                 min = hw_min + adj_range;
 439                 value &= ~HWP_MIN_PERF(~0L);
 440                 value |= HWP_MIN_PERF(min);
 441
 442                 adj_range = limits->max_perf_pct * range / 100;
 443                 max = hw_min + adj_range;
 444                 if (limits->no_turbo) {
 445                         hw_max = HWP_GUARANTEED_PERF(cap);
 446                         if (hw_max < max)
 447                                 max = hw_max;
 448                 }
 449
 450                 value &= ~HWP_MAX_PERF(~0L);
 451                 value |= HWP_MAX_PERF(max);
 452                 wrmsrl_on_cpu(cpu, MSR_HWP_REQUEST, value);
 453         }
 454 }
 455
 456 static void intel_pstate_hwp_set_online_cpus(void)
 457 {
 458         get_online_cpus();
 459         intel_pstate_hwp_set(cpu_online_mask);
 460         put_online_cpus();
 461 }
 462
 463 /************************** debugfs begin ************************/
 464 static int pid_param_set(void *data, u64 val)
 465 {
 466         *(u32 *)data = val;
 467         intel_pstate_reset_all_pid();
 468         return 0;
 469 }
 470
 471 static int pid_param_get(void *data, u64 *val)
 472 {
 473         *val = *(u32 *)data;
 474         return 0;
 475 }
 476 DEFINE_SIMPLE_ATTRIBUTE(fops_pid_param, pid_param_get, pid_param_set, "%llu\n");
 477
 478 struct pid_param {
 479         char *name;
 480         void *value;
 481 };
 482
 483 static struct pid_param pid_files[] = {
 484         {"sample_rate_ms", &pid_params.sample_rate_ms},
 485         {"d_gain_pct", &pid_params.d_gain_pct},
 486         {"i_gain_pct", &pid_params.i_gain_pct},
 487         {"deadband", &pid_params.deadband},
 488         {"setpoint", &pid_params.setpoint},
 489         {"p_gain_pct", &pid_params.p_gain_pct},
 490         {NULL, NULL}
 491 };
 492
 493 static void __init intel_pstate_debug_expose_params(void)
 494 {
 495         struct dentry *debugfs_parent;
 496         int i = 0;
 497
 498         if (hwp_active)
 499                 return;
 500         debugfs_parent = debugfs_create_dir("pstate_snb", NULL);
 501         if (IS_ERR_OR_NULL(debugfs_parent))
 502                 return;
 503         while (pid_files[i].name) {
 504                 debugfs_create_file(pid_files[i].name, 0660,
 505                                     debugfs_parent, pid_files[i].value,
 506                                     &fops_pid_param);
 507                 i++;
 508         }
 509 }
 510
 511 /************************** debugfs end ************************/
 512
 513 /************************** sysfs begin ************************/
 514 #define show_one(file_name, object)                                     \
 515         static ssize_t show_##file_name                                 \
 516         (struct kobject *kobj, struct attribute *attr, char *buf)       \
 517         {                                                               \
 518                 return sprintf(buf, "%u\n", limits->object);            \
 519         }
 520
 521 static ssize_t show_turbo_pct(struct kobject *kobj,
 522                                 struct attribute *attr, char *buf)
 523 {
 524         struct cpudata *cpu;
 525         int total, no_turbo, turbo_pct;
 526         uint32_t turbo_fp;
 527
 528         cpu = all_cpu_data[0];
 529
 530         total = cpu->pstate.turbo_pstate - cpu->pstate.min_pstate + 1;
 531         no_turbo = cpu->pstate.max_pstate - cpu->pstate.min_pstate + 1;
 532         turbo_fp = div_fp(no_turbo, total);
 533         turbo_pct = 100 - fp_toint(mul_fp(turbo_fp, int_tofp(100)));
 534         return sprintf(buf, "%u\n", turbo_pct);
 535 }
 536
 537 static ssize_t show_num_pstates(struct kobject *kobj,
 538                                 struct attribute *attr, char *buf)
 539 {
 540         struct cpudata *cpu;
 541         int total;
 542
 543         cpu = all_cpu_data[0];
 544         total = cpu->pstate.turbo_pstate - cpu->pstate.min_pstate + 1;
 545         return sprintf(buf, "%u\n", total);
 546 }
 547
 548 static ssize_t show_no_turbo(struct kobject *kobj,
 549                              struct attribute *attr, char *buf)
 550 {
 551         ssize_t ret;
 552
 553         update_turbo_state();
 554         if (limits->turbo_disabled)
 555                 ret = sprintf(buf, "%u\n", limits->turbo_disabled);
 556         else
 557                 ret = sprintf(buf, "%u\n", limits->no_turbo);
 558
 559         return ret;
 560 }
 561
 562 static ssize_t store_no_turbo(struct kobject *a, struct attribute *b,
 563                               const char *buf, size_t count)
 564 {
 565         unsigned int input;
 566         int ret;
 567
 568         ret = sscanf(buf, "%u", &input);
 569         if (ret != 1)
 570                 return -EINVAL;
 571
 572         update_turbo_state();
 573         if (limits->turbo_disabled) {
 574                 pr_warn("intel_pstate: Turbo disabled by BIOS or unavailable on processor\n");
 575                 return -EPERM;
 576         }
 577
 578         limits->no_turbo = clamp_t(int, input, 0, 1);
 579
 580         if (hwp_active)
 581                 intel_pstate_hwp_set_online_cpus();
 582
 583         return count;
 584 }
 585
 586 static ssize_t store_max_perf_pct(struct kobject *a, struct attribute *b,
 587                                   const char *buf, size_t count)
 588 {
 589         unsigned int input;
 590         int ret;
 591
 592         ret = sscanf(buf, "%u", &input);
 593         if (ret != 1)
 594                 return -EINVAL;
 595
 596         limits->max_sysfs_pct = clamp_t(int, input, 0 , 100);
 597         limits->max_perf_pct = min(limits->max_policy_pct,
 598                                    limits->max_sysfs_pct);
 599         limits->max_perf_pct = max(limits->min_policy_pct,
 600                                    limits->max_perf_pct);
 601         limits->max_perf_pct = max(limits->min_perf_pct,
 602                                    limits->max_perf_pct);
 603         limits->max_perf = div_fp(limits->max_perf_pct, 100);
 604
 605         if (hwp_active)
 606                 intel_pstate_hwp_set_online_cpus();
 607         return count;
 608 }
 609
 610 static ssize_t store_min_perf_pct(struct kobject *a, struct attribute *b,
 611                                   const char *buf, size_t count)
 612 {
 613         unsigned int input;
 614         int ret;
 615
 616         ret = sscanf(buf, "%u", &input);
 617         if (ret != 1)
 618                 return -EINVAL;
 619
 620         limits->min_sysfs_pct = clamp_t(int, input, 0 , 100);
 621         limits->min_perf_pct = max(limits->min_policy_pct,
 622                                    limits->min_sysfs_pct);
 623         limits->min_perf_pct = min(limits->max_policy_pct,
 624                                    limits->min_perf_pct);
 625         limits->min_perf_pct = min(limits->max_perf_pct,
 626                                    limits->min_perf_pct);
 627         limits->min_perf = div_fp(limits->min_perf_pct, 100);
 628
 629         if (hwp_active)
 630                 intel_pstate_hwp_set_online_cpus();
 631         return count;
 632 }
 633
 634 show_one(max_perf_pct, max_perf_pct);
 635 show_one(min_perf_pct, min_perf_pct);
 636
 637 define_one_global_rw(no_turbo);
 638 define_one_global_rw(max_perf_pct);
 639 define_one_global_rw(min_perf_pct);
 640 define_one_global_ro(turbo_pct);
 641 define_one_global_ro(num_pstates);
 642
 643 static struct attribute *intel_pstate_attributes[] = {
 644         &no_turbo.attr,
 645         &max_perf_pct.attr,
 646         &min_perf_pct.attr,
 647         &turbo_pct.attr,
 648         &num_pstates.attr,
 649         NULL
 650 };
 651
 652 static struct attribute_group intel_pstate_attr_group = {
 653         .attrs = intel_pstate_attributes,
 654 };
 655
 656 static void __init intel_pstate_sysfs_expose_params(void)
 657 {
 658         struct kobject *intel_pstate_kobject;
 659         int rc;
 660
 661         intel_pstate_kobject = kobject_create_and_add("intel_pstate",
 662                                                 &cpu_subsys.dev_root->kobj);
 663         BUG_ON(!intel_pstate_kobject);
 664         rc = sysfs_create_group(intel_pstate_kobject, &intel_pstate_attr_group);
 665         BUG_ON(rc);
 666 }
 667 /************************** sysfs end ************************/
 668
 669 static void intel_pstate_hwp_enable(struct cpudata *cpudata)
 670 {
 671         /* First disable HWP notification interrupt as we don't process them */
 672         wrmsrl_on_cpu(cpudata->cpu, MSR_HWP_INTERRUPT, 0x00);
 673
 674         wrmsrl_on_cpu(cpudata->cpu, MSR_PM_ENABLE, 0x1);
 675 }
 676
 677 static int atom_get_min_pstate(void)
 678 {
 679         u64 value;
 680
 681         rdmsrl(ATOM_RATIOS, value);
 682         return (value >> 8) & 0x7F;
 683 }
 684
 685 static int atom_get_max_pstate(void)
 686 {
 687         u64 value;
 688
 689         rdmsrl(ATOM_RATIOS, value);
 690         return (value >> 16) & 0x7F;
 691 }
 692
 693 static int atom_get_turbo_pstate(void)
 694 {
 695         u64 value;
 696
 697         rdmsrl(ATOM_TURBO_RATIOS, value);
 698         return value & 0x7F;
 699 }
 700
 701 static u64 atom_get_val(struct cpudata *cpudata, int pstate)
 702 {
 703         u64 val;
 704         int32_t vid_fp;
 705         u32 vid;
 706
 707         val = (u64)pstate << 8;
 708         if (limits->no_turbo && !limits->turbo_disabled)
 709                 val |= (u64)1 << 32;
 710
 711         vid_fp = cpudata->vid.min + mul_fp(
 712                 int_tofp(pstate - cpudata->pstate.min_pstate),
 713                 cpudata->vid.ratio);
 714
 715         vid_fp = clamp_t(int32_t, vid_fp, cpudata->vid.min, cpudata->vid.max);
 716         vid = ceiling_fp(vid_fp);
 717
 718         if (pstate > cpudata->pstate.max_pstate)
 719                 vid = cpudata->vid.turbo;
 720
 721         return val | vid;
 722 }
 723
 724 static int silvermont_get_scaling(void)
 725 {
 726         u64 value;
 727         int i;
 728         /* Defined in Table 35-6 from SDM (Sept 2015) */
 729         static int silvermont_freq_table[] = {
 730                 83300, 100000, 133300, 116700, 80000};
 731
 732         rdmsrl(MSR_FSB_FREQ, value);
 733         i = value & 0x7;
 734         WARN_ON(i > 4);
 735
 736         return silvermont_freq_table[i];
 737 }
 738
 739 static int airmont_get_scaling(void)
 740 {
 741         u64 value;
 742         int i;
 743         /* Defined in Table 35-10 from SDM (Sept 2015) */
 744         static int airmont_freq_table[] = {
 745                 83300, 100000, 133300, 116700, 80000,
 746                 93300, 90000, 88900, 87500};
 747
 748         rdmsrl(MSR_FSB_FREQ, value);
 749         i = value & 0xF;
 750         WARN_ON(i > 8);
 751
 752         return airmont_freq_table[i];
 753 }
 754
 755 static void atom_get_vid(struct cpudata *cpudata)
 756 {
 757         u64 value;
 758
 759         rdmsrl(ATOM_VIDS, value);
 760         cpudata->vid.min = int_tofp((value >> 8) & 0x7f);
 761         cpudata->vid.max = int_tofp((value >> 16) & 0x7f);
 762         cpudata->vid.ratio = div_fp(
 763                 cpudata->vid.max - cpudata->vid.min,
 764                 int_tofp(cpudata->pstate.max_pstate -
 765                         cpudata->pstate.min_pstate));
 766
 767         rdmsrl(ATOM_TURBO_VIDS, value);
 768         cpudata->vid.turbo = value & 0x7f;
 769 }
 770
 771 static int core_get_min_pstate(void)
 772 {
 773         u64 value;
 774
 775         rdmsrl(MSR_PLATFORM_INFO, value);
 776         return (value >> 40) & 0xFF;
 777 }
 778
 779 static int core_get_max_pstate_physical(void)
 780 {
 781         u64 value;
 782
 783         rdmsrl(MSR_PLATFORM_INFO, value);
 784         return (value >> 8) & 0xFF;
 785 }
 786
 787 static int core_get_max_pstate(void)
 788 {
 789         u64 tar;
 790         u64 plat_info;
 791         int max_pstate;
 792         int err;
 793
 794         rdmsrl(MSR_PLATFORM_INFO, plat_info);
 795         max_pstate = (plat_info >> 8) & 0xFF;
 796
 797         err = rdmsrl_safe(MSR_TURBO_ACTIVATION_RATIO, &tar);
 798         if (!err) {
 799                 /* Do some sanity checking for safety */
 800                 if (plat_info & 0x600000000) {
 801                         u64 tdp_ctrl;
 802                         u64 tdp_ratio;
 803                         int tdp_msr;
 804
 805                         err = rdmsrl_safe(MSR_CONFIG_TDP_CONTROL, &tdp_ctrl);
 806                         if (err)
 807                                 goto skip_tar;
 808
 809                         tdp_msr = MSR_CONFIG_TDP_NOMINAL + tdp_ctrl;
 810                         err = rdmsrl_safe(tdp_msr, &tdp_ratio);
 811                         if (err)
 812                                 goto skip_tar;
 813
 814                         if (tdp_ratio - 1 == tar) {
 815                                 max_pstate = tar;
 816                                 pr_debug("max_pstate=TAC %x\n", max_pstate);
 817                         } else {
 818                                 goto skip_tar;
 819                         }
 820                 }
 821         }
 822
 823 skip_tar:
 824         return max_pstate;
 825 }
 826
 827 static int core_get_turbo_pstate(void)
 828 {
 829         u64 value;
 830         int nont, ret;
 831
 832         rdmsrl(MSR_NHM_TURBO_RATIO_LIMIT, value);
 833         nont = core_get_max_pstate();
 834         ret = (value) & 255;
 835         if (ret <= nont)
 836                 ret = nont;
 837         return ret;
 838 }
 839
 840 static inline int core_get_scaling(void)
 841 {
 842         return 100000;
 843 }
 844
 845 static u64 core_get_val(struct cpudata *cpudata, int pstate)
 846 {
 847         u64 val;
 848
 849         val = (u64)pstate << 8;
 850         if (limits->no_turbo && !limits->turbo_disabled)
 851                 val |= (u64)1 << 32;
 852
 853         return val;
 854 }
 855
 856 static int knl_get_turbo_pstate(void)
 857 {
 858         u64 value;
 859         int nont, ret;
 860
 861         rdmsrl(MSR_NHM_TURBO_RATIO_LIMIT, value);
 862         nont = core_get_max_pstate();
 863         ret = (((value) >> 8) & 0xFF);
 864         if (ret <= nont)
 865                 ret = nont;
 866         return ret;
 867 }
 868
 869 static struct cpu_defaults core_params = {
 870         .pid_policy = {
 871                 .sample_rate_ms = 10,
 872                 .deadband = 0,
 873                 .setpoint = 97,
 874                 .p_gain_pct = 20,
 875                 .d_gain_pct = 0,
 876                 .i_gain_pct = 0,
 877         },
 878         .funcs = {
 879                 .get_max = core_get_max_pstate,
 880                 .get_max_physical = core_get_max_pstate_physical,
 881                 .get_min = core_get_min_pstate,
 882                 .get_turbo = core_get_turbo_pstate,
 883                 .get_scaling = core_get_scaling,
 884                 .get_val = core_get_val,
 885                 .get_target_pstate = get_target_pstate_use_performance,
 886         },
 887 };
 888
 889 static struct cpu_defaults silvermont_params = {
 890         .pid_policy = {
 891                 .sample_rate_ms = 10,
 892                 .deadband = 0,
 893                 .setpoint = 60,
 894                 .p_gain_pct = 14,
 895                 .d_gain_pct = 0,
 896                 .i_gain_pct = 4,
 897         },
 898         .funcs = {
 899                 .get_max = atom_get_max_pstate,
 900                 .get_max_physical = atom_get_max_pstate,
 901                 .get_min = atom_get_min_pstate,
 902                 .get_turbo = atom_get_turbo_pstate,
 903                 .get_val = atom_get_val,
 904                 .get_scaling = silvermont_get_scaling,
 905                 .get_vid = atom_get_vid,
 906                 .get_target_pstate = get_target_pstate_use_cpu_load,
 907         },
 908 };
 909
 910 static struct cpu_defaults airmont_params = {
 911         .pid_policy = {
 912                 .sample_rate_ms = 10,
 913                 .deadband = 0,
 914                 .setpoint = 60,
 915                 .p_gain_pct = 14,
 916                 .d_gain_pct = 0,
 917                 .i_gain_pct = 4,
 918         },
 919         .funcs = {
 920                 .get_max = atom_get_max_pstate,
 921                 .get_max_physical = atom_get_max_pstate,
 922                 .get_min = atom_get_min_pstate,
 923                 .get_turbo = atom_get_turbo_pstate,
 924                 .get_val = atom_get_val,
 925                 .get_scaling = airmont_get_scaling,
 926                 .get_vid = atom_get_vid,
 927                 .get_target_pstate = get_target_pstate_use_cpu_load,
 928         },
 929 };
 930
 931 static struct cpu_defaults knl_params = {
 932         .pid_policy = {
 933                 .sample_rate_ms = 10,
 934                 .deadband = 0,
 935                 .setpoint = 97,
 936                 .p_gain_pct = 20,
 937                 .d_gain_pct = 0,
 938                 .i_gain_pct = 0,
 939         },
 940         .funcs = {
 941                 .get_max = core_get_max_pstate,
 942                 .get_max_physical = core_get_max_pstate_physical,
 943                 .get_min = core_get_min_pstate,
 944                 .get_turbo = knl_get_turbo_pstate,
 945                 .get_scaling = core_get_scaling,
 946                 .get_val = core_get_val,
 947                 .get_target_pstate = get_target_pstate_use_performance,
 948         },
 949 };
 950
 951 static void intel_pstate_get_min_max(struct cpudata *cpu, int *min, int *max)
 952 {
 953         int max_perf = cpu->pstate.turbo_pstate;
 954         int max_perf_adj;
 955         int min_perf;
 956
 957         if (limits->no_turbo || limits->turbo_disabled)
 958                 max_perf = cpu->pstate.max_pstate;
 959
 960         /*
 961          * performance can be limited by user through sysfs, by cpufreq
 962          * policy, or by cpu specific default values determined through
 963          * experimentation.
 964          */
 965         max_perf_adj = fp_toint(max_perf * limits->max_perf);
 966         *max = clamp_t(int, max_perf_adj,
 967                         cpu->pstate.min_pstate, cpu->pstate.turbo_pstate);
 968
 969         min_perf = fp_toint(max_perf * limits->min_perf);
 970         *min = clamp_t(int, min_perf, cpu->pstate.min_pstate, max_perf);
 971 }
 972
 973 static inline void intel_pstate_record_pstate(struct cpudata *cpu, int pstate)
 974 {
 975         trace_cpu_frequency(pstate * cpu->pstate.scaling, cpu->cpu);
 976         cpu->pstate.current_pstate = pstate;
 977 }
 978
 979 static void intel_pstate_set_min_pstate(struct cpudata *cpu)
 980 {
 981         int pstate = cpu->pstate.min_pstate;
 982
 983         intel_pstate_record_pstate(cpu, pstate);
 984         /*
 985          * Generally, there is no guarantee that this code will always run on
 986          * the CPU being updated, so force the register update to run on the
 987          * right CPU.
 988          */
 989         wrmsrl_on_cpu(cpu->cpu, MSR_IA32_PERF_CTL,
 990                       pstate_funcs.get_val(cpu, pstate));
 991 }
 992
 993 static void intel_pstate_get_cpu_pstates(struct cpudata *cpu)
 994 {
 995         cpu->pstate.min_pstate = pstate_funcs.get_min();
 996         cpu->pstate.max_pstate = pstate_funcs.get_max();
 997         cpu->pstate.max_pstate_physical = pstate_funcs.get_max_physical();
 998         cpu->pstate.turbo_pstate = pstate_funcs.get_turbo();
 999         cpu->pstate.scaling = pstate_funcs.get_scaling();
1000
1001         if (pstate_funcs.get_vid)
1002                 pstate_funcs.get_vid(cpu);
1003
1004         intel_pstate_set_min_pstate(cpu);
1005 }
1006
1007 static inline void intel_pstate_calc_busy(struct cpudata *cpu)
1008 {
1009         struct sample *sample = &cpu->sample;
1010         int64_t core_pct;
1011
1012         core_pct = sample->aperf * int_tofp(100);
1013         core_pct = div64_u64(core_pct, sample->mperf);
1014
1015         sample->core_pct_busy = (int32_t)core_pct;
1016 }
1017
1018 static inline bool intel_pstate_sample(struct cpudata *cpu, u64 time)
1019 {
1020         u64 aperf, mperf;
1021         unsigned long flags;
1022         u64 tsc;
1023
1024         local_irq_save(flags);
1025         rdmsrl(MSR_IA32_APERF, aperf);
1026         rdmsrl(MSR_IA32_MPERF, mperf);
1027         tsc = rdtsc();
1028         if (cpu->prev_mperf == mperf || cpu->prev_tsc == tsc) {
1029                 local_irq_restore(flags);
1030                 return false;
1031         }
1032         local_irq_restore(flags);
1033
1034         cpu->last_sample_time = cpu->sample.time;
1035         cpu->sample.time = time;
1036         cpu->sample.aperf = aperf;
1037         cpu->sample.mperf = mperf;
1038         cpu->sample.tsc =  tsc;
1039         cpu->sample.aperf -= cpu->prev_aperf;
1040         cpu->sample.mperf -= cpu->prev_mperf;
1041         cpu->sample.tsc -= cpu->prev_tsc;
1042
1043         cpu->prev_aperf = aperf;
1044         cpu->prev_mperf = mperf;
1045         cpu->prev_tsc = tsc;
1046         /*
1047          * First time this function is invoked in a given cycle, all of the
1048          * previous sample data fields are equal to zero or stale and they must
1049          * be populated with meaningful numbers for things to work, so assume
1050          * that sample.time will always be reset before setting the utilization
1051          * update hook and make the caller skip the sample then.
1052          */
1053         return !!cpu->last_sample_time;
1054 }
1055
1056 static inline int32_t get_avg_frequency(struct cpudata *cpu)
1057 {
1058         return div64_u64(cpu->pstate.max_pstate_physical * cpu->sample.aperf *
1059                 cpu->pstate.scaling, cpu->sample.mperf);
1060 }
1061
1062 static inline int32_t get_target_pstate_use_cpu_load(struct cpudata *cpu)
1063 {
1064         struct sample *sample = &cpu->sample;
1065         u64 cummulative_iowait, delta_iowait_us;
1066         u64 delta_iowait_mperf;
1067         u64 mperf, now;
1068         int32_t cpu_load;
1069
1070         cummulative_iowait = get_cpu_iowait_time_us(cpu->cpu, &now);
1071
1072         /*
1073          * Convert iowait time into number of IO cycles spent at max_freq.
1074          * IO is considered as busy only for the cpu_load algorithm. For
1075          * performance this is not needed since we always try to reach the
1076          * maximum P-State, so we are already boosting the IOs.
1077          */
1078         delta_iowait_us = cummulative_iowait - cpu->prev_cummulative_iowait;
1079         delta_iowait_mperf = div64_u64(delta_iowait_us * cpu->pstate.scaling *
1080                 cpu->pstate.max_pstate, MSEC_PER_SEC);
1081
1082         mperf = cpu->sample.mperf + delta_iowait_mperf;
1083         cpu->prev_cummulative_iowait = cummulative_iowait;
1084
1085         /*
1086          * The load can be estimated as the ratio of the mperf counter
1087          * running at a constant frequency during active periods
1088          * (C0) and the time stamp counter running at the same frequency
1089          * also during C-states.
1090          */
1091         cpu_load = div64_u64(int_tofp(100) * mperf, sample->tsc);
1092         cpu->sample.busy_scaled = cpu_load;
1093
1094         return cpu->pstate.current_pstate - pid_calc(&cpu->pid, cpu_load);
1095 }
1096
1097 static inline int32_t get_target_pstate_use_performance(struct cpudata *cpu)
1098 {
1099         int32_t core_busy, max_pstate, current_pstate, sample_ratio;
1100         u64 duration_ns;
1101
1102         intel_pstate_calc_busy(cpu);
1103
1104         /*
1105          * core_busy is the ratio of actual performance to max
1106          * max_pstate is the max non turbo pstate available
1107          * current_pstate was the pstate that was requested during
1108          *      the last sample period.
1109          *
1110          * We normalize core_busy, which was our actual percent
1111          * performance to what we requested during the last sample
1112          * period. The result will be a percentage of busy at a
1113          * specified pstate.
1114          */
1115         core_busy = cpu->sample.core_pct_busy;
1116         max_pstate = cpu->pstate.max_pstate_physical;
1117         current_pstate = cpu->pstate.current_pstate;
1118         core_busy = mul_fp(core_busy, div_fp(max_pstate, current_pstate));
1119
1120         /*
1121          * Since our utilization update callback will not run unless we are
1122          * in C0, check if the actual elapsed time is significantly greater (3x)
1123          * than our sample interval.  If it is, then we were idle for a long
1124          * enough period of time to adjust our busyness.
1125          */
1126         duration_ns = cpu->sample.time - cpu->last_sample_time;
1127         if ((s64)duration_ns > pid_params.sample_rate_ns * 3) {
1128                 sample_ratio = div_fp(pid_params.sample_rate_ns, duration_ns);
1129                 core_busy = mul_fp(core_busy, sample_ratio);
1130         }
1131
1132         cpu->sample.busy_scaled = core_busy;
1133         return cpu->pstate.current_pstate - pid_calc(&cpu->pid, core_busy);
1134 }
1135
1136 static inline void intel_pstate_update_pstate(struct cpudata *cpu, int pstate)
1137 {
1138         int max_perf, min_perf;
1139
1140         update_turbo_state();
1141
1142         intel_pstate_get_min_max(cpu, &min_perf, &max_perf);
1143         pstate = clamp_t(int, pstate, min_perf, max_perf);
1144         if (pstate == cpu->pstate.current_pstate)
1145                 return;
1146
1147         intel_pstate_record_pstate(cpu, pstate);
1148         wrmsrl(MSR_IA32_PERF_CTL, pstate_funcs.get_val(cpu, pstate));
1149 }
1150
1151 static inline void intel_pstate_adjust_busy_pstate(struct cpudata *cpu)
1152 {
1153         int from, target_pstate;
1154         struct sample *sample;
1155
1156         from = cpu->pstate.current_pstate;
1157
1158         target_pstate = pstate_funcs.get_target_pstate(cpu);
1159
1160         intel_pstate_update_pstate(cpu, target_pstate);
1161
1162         sample = &cpu->sample;
1163         trace_pstate_sample(fp_toint(sample->core_pct_busy),
1164                 fp_toint(sample->busy_scaled),
1165                 from,
1166                 cpu->pstate.current_pstate,
1167                 sample->mperf,
1168                 sample->aperf,
1169                 sample->tsc,
1170                 get_avg_frequency(cpu));
1171 }
1172
1173 static void intel_pstate_update_util(struct update_util_data *data, u64 time,
1174                                      unsigned long util, unsigned long max)
1175 {
1176         struct cpudata *cpu = container_of(data, struct cpudata, update_util);
1177         u64 delta_ns = time - cpu->sample.time;
1178
1179         if ((s64)delta_ns >= pid_params.sample_rate_ns) {
1180                 bool sample_taken = intel_pstate_sample(cpu, time);
1181
1182                 if (sample_taken && !hwp_active)
1183                         intel_pstate_adjust_busy_pstate(cpu);
1184         }
1185 }
1186
1187 #define ICPU(model, policy) \
1188         { X86_VENDOR_INTEL, 6, model, X86_FEATURE_APERFMPERF,\
1189                         (unsigned long)&policy }
1190
1191 static const struct x86_cpu_id intel_pstate_cpu_ids[] = {
1192         ICPU(0x2a, core_params),
1193         ICPU(0x2d, core_params),
1194         ICPU(0x37, silvermont_params),
1195         ICPU(0x3a, core_params),
1196         ICPU(0x3c, core_params),
1197         ICPU(0x3d, core_params),
1198         ICPU(0x3e, core_params),
1199         ICPU(0x3f, core_params),
1200         ICPU(0x45, core_params),
1201         ICPU(0x46, core_params),
1202         ICPU(0x47, core_params),
1203         ICPU(0x4c, airmont_params),
1204         ICPU(0x4e, core_params),
1205         ICPU(0x4f, core_params),
1206         ICPU(0x5e, core_params),
1207         ICPU(0x56, core_params),
1208         ICPU(0x57, knl_params),
1209         {}
1210 };
1211 MODULE_DEVICE_TABLE(x86cpu, intel_pstate_cpu_ids);
1212
1213 static const struct x86_cpu_id intel_pstate_cpu_oob_ids[] = {
1214         ICPU(0x56, core_params),
1215         {}
1216 };
1217
1218 static int intel_pstate_init_cpu(unsigned int cpunum)
1219 {
1220         struct cpudata *cpu;
1221
1222         if (!all_cpu_data[cpunum])
1223                 all_cpu_data[cpunum] = kzalloc(sizeof(struct cpudata),
1224                                                GFP_KERNEL);
1225         if (!all_cpu_data[cpunum])
1226                 return -ENOMEM;
1227
1228         cpu = all_cpu_data[cpunum];
1229
1230         cpu->cpu = cpunum;
1231
1232         if (hwp_active) {
1233                 intel_pstate_hwp_enable(cpu);
1234                 pid_params.sample_rate_ms = 50;
1235                 pid_params.sample_rate_ns = 50 * NSEC_PER_MSEC;
1236         }
1237
1238         intel_pstate_get_cpu_pstates(cpu);
1239
1240         intel_pstate_busy_pid_reset(cpu);
1241
1242         pr_debug("intel_pstate: controlling: cpu %d\n", cpunum);
1243
1244         return 0;
1245 }
1246
1247 static unsigned int intel_pstate_get(unsigned int cpu_num)
1248 {
1249         struct sample *sample;
1250         struct cpudata *cpu;
1251
1252         cpu = all_cpu_data[cpu_num];
1253         if (!cpu)
1254                 return 0;
1255         sample = &cpu->sample;
1256         return get_avg_frequency(cpu);
1257 }
1258
1259 static void intel_pstate_set_update_util_hook(unsigned int cpu_num)
1260 {
1261         struct cpudata *cpu = all_cpu_data[cpu_num];
1262
1263         /* Prevent intel_pstate_update_util() from using stale data. */
1264         cpu->sample.time = 0;
1265         cpufreq_add_update_util_hook(cpu_num, &cpu->update_util,
1266                                      intel_pstate_update_util);
1267 }
1268
1269 static void intel_pstate_clear_update_util_hook(unsigned int cpu)
1270 {
1271         cpufreq_remove_update_util_hook(cpu);
1272         synchronize_sched();
1273 }
1274
1275 static void intel_pstate_set_performance_limits(struct perf_limits *limits)
1276 {
1277         limits->no_turbo = 0;
1278         limits->turbo_disabled = 0;
1279         limits->max_perf_pct = 100;
1280         limits->max_perf = int_tofp(1);
1281         limits->min_perf_pct = 100;
1282         limits->min_perf = int_tofp(1);
1283         limits->max_policy_pct = 100;
1284         limits->max_sysfs_pct = 100;
1285         limits->min_policy_pct = 0;
1286         limits->min_sysfs_pct = 0;
1287 }
1288
1289 static int intel_pstate_set_policy(struct cpufreq_policy *policy)
1290 {
1291         if (!policy->cpuinfo.max_freq)
1292                 return -ENODEV;
1293
1294         intel_pstate_clear_update_util_hook(policy->cpu);
1295
1296         if (policy->policy == CPUFREQ_POLICY_PERFORMANCE) {
1297                 limits = &performance_limits;
1298                 if (policy->max >= policy->cpuinfo.max_freq) {
1299                         pr_debug("intel_pstate: set performance\n");
1300                         intel_pstate_set_performance_limits(limits);
1301                         goto out;
1302                 }
1303         } else {
1304                 pr_debug("intel_pstate: set powersave\n");
1305                 limits = &powersave_limits;
1306         }
1307
1308         limits->min_policy_pct = (policy->min * 100) / policy->cpuinfo.max_freq;
1309         limits->min_policy_pct = clamp_t(int, limits->min_policy_pct, 0 , 100);
1310         limits->max_policy_pct = DIV_ROUND_UP(policy->max * 100,
1311                                               policy->cpuinfo.max_freq);
1312         limits->max_policy_pct = clamp_t(int, limits->max_policy_pct, 0 , 100);
1313
1314         /* Normalize user input to [min_policy_pct, max_policy_pct] */
1315         limits->min_perf_pct = max(limits->min_policy_pct,
1316                                    limits->min_sysfs_pct);
1317         limits->min_perf_pct = min(limits->max_policy_pct,
1318                                    limits->min_perf_pct);
1319         limits->max_perf_pct = min(limits->max_policy_pct,
1320                                    limits->max_sysfs_pct);
1321         limits->max_perf_pct = max(limits->min_policy_pct,
1322                                    limits->max_perf_pct);
1323         limits->max_perf = round_up(limits->max_perf, FRAC_BITS);
1324
1325         /* Make sure min_perf_pct <= max_perf_pct */
1326         limits->min_perf_pct = min(limits->max_perf_pct, limits->min_perf_pct);
1327
1328         limits->min_perf = div_fp(limits->min_perf_pct, 100);
1329         limits->max_perf = div_fp(limits->max_perf_pct, 100);
1330
1331  out:
1332         intel_pstate_set_update_util_hook(policy->cpu);
1333
1334         if (hwp_active)
1335                 intel_pstate_hwp_set(policy->cpus);
1336
1337         return 0;
1338 }
1339
1340 static int intel_pstate_verify_policy(struct cpufreq_policy *policy)
1341 {
1342         cpufreq_verify_within_cpu_limits(policy);
1343
1344         if (policy->policy != CPUFREQ_POLICY_POWERSAVE &&
1345             policy->policy != CPUFREQ_POLICY_PERFORMANCE)
1346                 return -EINVAL;
1347
1348         return 0;
1349 }
1350
1351 static void intel_pstate_stop_cpu(struct cpufreq_policy *policy)
1352 {
1353         int cpu_num = policy->cpu;
1354         struct cpudata *cpu = all_cpu_data[cpu_num];
1355
1356         pr_debug("intel_pstate: CPU %d exiting\n", cpu_num);
1357
1358         intel_pstate_clear_update_util_hook(cpu_num);
1359
1360         if (hwp_active)
1361                 return;
1362
1363         intel_pstate_set_min_pstate(cpu);
1364 }
1365
1366 static int intel_pstate_cpu_init(struct cpufreq_policy *policy)
1367 {
1368         struct cpudata *cpu;
1369         int rc;
1370
1371         rc = intel_pstate_init_cpu(policy->cpu);
1372         if (rc)
1373                 return rc;
1374
1375         cpu = all_cpu_data[policy->cpu];
1376
1377         if (limits->min_perf_pct == 100 && limits->max_perf_pct == 100)
1378                 policy->policy = CPUFREQ_POLICY_PERFORMANCE;
1379         else
1380                 policy->policy = CPUFREQ_POLICY_POWERSAVE;
1381
1382         policy->min = cpu->pstate.min_pstate * cpu->pstate.scaling;
1383         policy->max = cpu->pstate.turbo_pstate * cpu->pstate.scaling;
1384
1385         /* cpuinfo and default policy values */
1386         policy->cpuinfo.min_freq = cpu->pstate.min_pstate * cpu->pstate.scaling;
1387         policy->cpuinfo.max_freq =
1388                 cpu->pstate.turbo_pstate * cpu->pstate.scaling;
1389         policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
1390         cpumask_set_cpu(policy->cpu, policy->cpus);
1391
1392         return 0;
1393 }
1394
1395 static struct cpufreq_driver intel_pstate_driver = {
1396         .flags          = CPUFREQ_CONST_LOOPS,
1397         .verify         = intel_pstate_verify_policy,
1398         .setpolicy      = intel_pstate_set_policy,
1399         .get            = intel_pstate_get,
1400         .init           = intel_pstate_cpu_init,
1401         .stop_cpu       = intel_pstate_stop_cpu,
1402         .name           = "intel_pstate",
1403 };
1404
1405 static int __initdata no_load;
1406 static int __initdata no_hwp;
1407 static int __initdata hwp_only;
1408 static unsigned int force_load;
1409
1410 static int intel_pstate_msrs_not_valid(void)
1411 {
1412         if (!pstate_funcs.get_max() ||
1413             !pstate_funcs.get_min() ||
1414             !pstate_funcs.get_turbo())
1415                 return -ENODEV;
1416
1417         return 0;
1418 }
1419
1420 static void copy_pid_params(struct pstate_adjust_policy *policy)
1421 {
1422         pid_params.sample_rate_ms = policy->sample_rate_ms;
1423         pid_params.sample_rate_ns = pid_params.sample_rate_ms * NSEC_PER_MSEC;
1424         pid_params.p_gain_pct = policy->p_gain_pct;
1425         pid_params.i_gain_pct = policy->i_gain_pct;
1426         pid_params.d_gain_pct = policy->d_gain_pct;
1427         pid_params.deadband = policy->deadband;
1428         pid_params.setpoint = policy->setpoint;
1429 }
1430
1431 static void copy_cpu_funcs(struct pstate_funcs *funcs)
1432 {
1433         pstate_funcs.get_max   = funcs->get_max;
1434         pstate_funcs.get_max_physical = funcs->get_max_physical;
1435         pstate_funcs.get_min   = funcs->get_min;
1436         pstate_funcs.get_turbo = funcs->get_turbo;
1437         pstate_funcs.get_scaling = funcs->get_scaling;
1438         pstate_funcs.get_val   = funcs->get_val;
1439         pstate_funcs.get_vid   = funcs->get_vid;
1440         pstate_funcs.get_target_pstate = funcs->get_target_pstate;
1441
1442 }
1443
1444 #if IS_ENABLED(CONFIG_ACPI)
1445 #include <acpi/processor.h>
1446
1447 static bool intel_pstate_no_acpi_pss(void)
1448 {
1449         int i;
1450
1451         for_each_possible_cpu(i) {
1452                 acpi_status status;
1453                 union acpi_object *pss;
1454                 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1455                 struct acpi_processor *pr = per_cpu(processors, i);
1456
1457                 if (!pr)
1458                         continue;
1459
1460                 status = acpi_evaluate_object(pr->handle, "_PSS", NULL, &buffer);
1461                 if (ACPI_FAILURE(status))
1462                         continue;
1463
1464                 pss = buffer.pointer;
1465                 if (pss && pss->type == ACPI_TYPE_PACKAGE) {
1466                         kfree(pss);
1467                         return false;
1468                 }
1469
1470                 kfree(pss);
1471         }
1472
1473         return true;
1474 }
1475
1476 static bool intel_pstate_has_acpi_ppc(void)
1477 {
1478         int i;
1479
1480         for_each_possible_cpu(i) {
1481                 struct acpi_processor *pr = per_cpu(processors, i);
1482
1483                 if (!pr)
1484                         continue;
1485                 if (acpi_has_method(pr->handle, "_PPC"))
1486                         return true;
1487         }
1488         return false;
1489 }
1490
1491 enum {
1492         PSS,
1493         PPC,
1494 };
1495
1496 struct hw_vendor_info {
1497         u16  valid;
1498         char oem_id[ACPI_OEM_ID_SIZE];
1499         char oem_table_id[ACPI_OEM_TABLE_ID_SIZE];
1500         int  oem_pwr_table;
1501 };
1502
1503 /* Hardware vendor-specific info that has its own power management modes */
1504 static struct hw_vendor_info vendor_info[] = {
1505         {1, "HP    ", "ProLiant", PSS},
1506         {1, "ORACLE", "X4-2    ", PPC},
1507         {1, "ORACLE", "X4-2L   ", PPC},
1508         {1, "ORACLE", "X4-2B   ", PPC},
1509         {1, "ORACLE", "X3-2    ", PPC},
1510         {1, "ORACLE", "X3-2L   ", PPC},
1511         {1, "ORACLE", "X3-2B   ", PPC},
1512         {1, "ORACLE", "X4470M2 ", PPC},
1513         {1, "ORACLE", "X4270M3 ", PPC},
1514         {1, "ORACLE", "X4270M2 ", PPC},
1515         {1, "ORACLE", "X4170M2 ", PPC},
1516         {1, "ORACLE", "X4170 M3", PPC},
1517         {1, "ORACLE", "X4275 M3", PPC},
1518         {1, "ORACLE", "X6-2    ", PPC},
1519         {1, "ORACLE", "Sudbury ", PPC},
1520         {0, "", ""},
1521 };
1522
1523 static bool intel_pstate_platform_pwr_mgmt_exists(void)
1524 {
1525         struct acpi_table_header hdr;
1526         struct hw_vendor_info *v_info;
1527         const struct x86_cpu_id *id;
1528         u64 misc_pwr;
1529
1530         id = x86_match_cpu(intel_pstate_cpu_oob_ids);
1531         if (id) {
1532                 rdmsrl(MSR_MISC_PWR_MGMT, misc_pwr);
1533                 if ( misc_pwr & (1 << 8))
1534                         return true;
1535         }
1536
1537         if (acpi_disabled ||
1538             ACPI_FAILURE(acpi_get_table_header(ACPI_SIG_FADT, 0, &hdr)))
1539                 return false;
1540
1541         for (v_info = vendor_info; v_info->valid; v_info++) {
1542                 if (!strncmp(hdr.oem_id, v_info->oem_id, ACPI_OEM_ID_SIZE) &&
1543                         !strncmp(hdr.oem_table_id, v_info->oem_table_id,
1544                                                 ACPI_OEM_TABLE_ID_SIZE))
1545                         switch (v_info->oem_pwr_table) {
1546                         case PSS:
1547                                 return intel_pstate_no_acpi_pss();
1548                         case PPC:
1549                                 return intel_pstate_has_acpi_ppc() &&
1550                                         (!force_load);
1551                         }
1552         }
1553
1554         return false;
1555 }
1556 #else /* CONFIG_ACPI not enabled */
1557 static inline bool intel_pstate_platform_pwr_mgmt_exists(void) { return false; }
1558 static inline bool intel_pstate_has_acpi_ppc(void) { return false; }
1559 #endif /* CONFIG_ACPI */
1560
1561 static const struct x86_cpu_id hwp_support_ids[] __initconst = {
1562         { X86_VENDOR_INTEL, 6, X86_MODEL_ANY, X86_FEATURE_HWP },
1563         {}
1564 };
1565
1566 static int __init intel_pstate_init(void)
1567 {
1568         int cpu, rc = 0;
1569         const struct x86_cpu_id *id;
1570         struct cpu_defaults *cpu_def;
1571
1572         if (no_load)
1573                 return -ENODEV;
1574
1575         if (x86_match_cpu(hwp_support_ids) && !no_hwp) {
1576                 copy_cpu_funcs(&core_params.funcs);
1577                 hwp_active++;
1578                 goto hwp_cpu_matched;
1579         }
1580
1581         id = x86_match_cpu(intel_pstate_cpu_ids);
1582         if (!id)
1583                 return -ENODEV;
1584
1585         cpu_def = (struct cpu_defaults *)id->driver_data;
1586
1587         copy_pid_params(&cpu_def->pid_policy);
1588         copy_cpu_funcs(&cpu_def->funcs);
1589
1590         if (intel_pstate_msrs_not_valid())
1591                 return -ENODEV;
1592
1593 hwp_cpu_matched:
1594         /*
1595          * The Intel pstate driver will be ignored if the platform
1596          * firmware has its own power management modes.
1597          */
1598         if (intel_pstate_platform_pwr_mgmt_exists())
1599                 return -ENODEV;
1600
1601         pr_info("Intel P-state driver initializing.\n");
1602
1603         all_cpu_data = vzalloc(sizeof(void *) * num_possible_cpus());
1604         if (!all_cpu_data)
1605                 return -ENOMEM;
1606
1607         if (!hwp_active && hwp_only)
1608                 goto out;
1609
1610         rc = cpufreq_register_driver(&intel_pstate_driver);
1611         if (rc)
1612                 goto out;
1613
1614         intel_pstate_debug_expose_params();
1615         intel_pstate_sysfs_expose_params();
1616
1617         if (hwp_active)
1618                 pr_info("intel_pstate: HWP enabled\n");
1619
1620         return rc;
1621 out:
1622         get_online_cpus();
1623         for_each_online_cpu(cpu) {
1624                 if (all_cpu_data[cpu]) {
1625                         intel_pstate_clear_update_util_hook(cpu);
1626                         kfree(all_cpu_data[cpu]);
1627                 }
1628         }
1629
1630         put_online_cpus();
1631         vfree(all_cpu_data);
1632         return -ENODEV;
1633 }
1634 device_initcall(intel_pstate_init);
1635
1636 static int __init intel_pstate_setup(char *str)
1637 {
1638         if (!str)
1639                 return -EINVAL;
1640
1641         if (!strcmp(str, "disable"))
1642                 no_load = 1;
1643         if (!strcmp(str, "no_hwp")) {
1644                 pr_info("intel_pstate: HWP disabled\n");
1645                 no_hwp = 1;
1646         }
1647         if (!strcmp(str, "force"))
1648                 force_load = 1;
1649         if (!strcmp(str, "hwp_only"))
1650                 hwp_only = 1;
1651         return 0;
1652 }
1653 early_param("intel_pstate", intel_pstate_setup);
1654
1655 MODULE_AUTHOR("Dirk Brandewie <dirk.j.brandewie@intel.com>");
1656 MODULE_DESCRIPTION("'intel_pstate' - P state driver Intel Core processors");
1657 MODULE_LICENSE("GPL");