drivers/cpufreq/acpi-cpufreq.c

   1 /*
   2  * acpi-cpufreq.c - ACPI Processor P-States Driver
   3  *
   4  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
   5  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
   6  *  Copyright (C) 2002 - 2004 Dominik Brodowski <linux@brodo.de>
   7  *  Copyright (C) 2006       Denis Sadykov <denis.m.sadykov@intel.com>
   8  *
   9  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  10  *
  11  *  This program is free software; you can redistribute it and/or modify
  12  *  it under the terms of the GNU General Public License as published by
  13  *  the Free Software Foundation; either version 2 of the License, or (at
  14  *  your option) any later version.
  15  *
  16  *  This program is distributed in the hope that it will be useful, but
  17  *  WITHOUT ANY WARRANTY; without even the implied warranty of
  18  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  19  *  General Public License for more details.
  20  *
  21  *  You should have received a copy of the GNU General Public License along
  22  *  with this program; if not, write to the Free Software Foundation, Inc.,
  23  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  24  *
  25  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  26  */
  27
  28 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  29
  30 #include <linux/kernel.h>
  31 #include <linux/module.h>
  32 #include <linux/init.h>
  33 #include <linux/smp.h>
  34 #include <linux/sched.h>
  35 #include <linux/cpufreq.h>
  36 #include <linux/compiler.h>
  37 #include <linux/dmi.h>
  38 #include <linux/slab.h>
  39
  40 #include <linux/acpi.h>
  41 #include <linux/io.h>
  42 #include <linux/delay.h>
  43 #include <linux/uaccess.h>
  44
  45 #include <acpi/processor.h>
  46
  47 #include <asm/msr.h>
  48 #include <asm/processor.h>
  49 #include <asm/cpufeature.h>
  50
  51 MODULE_AUTHOR("Paul Diefenbaugh, Dominik Brodowski");
  52 MODULE_DESCRIPTION("ACPI Processor P-States Driver");
  53 MODULE_LICENSE("GPL");
  54
  55 enum {
  56         UNDEFINED_CAPABLE = 0,
  57         SYSTEM_INTEL_MSR_CAPABLE,
  58         SYSTEM_AMD_MSR_CAPABLE,
  59         SYSTEM_IO_CAPABLE,
  60 };
  61
  62 #define INTEL_MSR_RANGE         (0xffff)
  63 #define AMD_MSR_RANGE           (0x7)
  64
  65 #define MSR_K7_HWCR_CPB_DIS     (1ULL << 25)
  66
  67 struct acpi_cpufreq_data {
  68         unsigned int resume;
  69         unsigned int cpu_feature;
  70         unsigned int acpi_perf_cpu;
  71         cpumask_var_t freqdomain_cpus;
  72         void (*cpu_freq_write)(struct acpi_pct_register *reg, u32 val);
  73         u32 (*cpu_freq_read)(struct acpi_pct_register *reg);
  74 };
  75
  76 /* acpi_perf_data is a pointer to percpu data. */
  77 static struct acpi_processor_performance __percpu *acpi_perf_data;
  78
  79 static inline struct acpi_processor_performance *to_perf_data(struct acpi_cpufreq_data *data)
  80 {
  81         return per_cpu_ptr(acpi_perf_data, data->acpi_perf_cpu);
  82 }
  83
  84 static struct cpufreq_driver acpi_cpufreq_driver;
  85
  86 static unsigned int acpi_pstate_strict;
  87
  88 static bool boost_state(unsigned int cpu)
  89 {
  90         u32 lo, hi;
  91         u64 msr;
  92
  93         switch (boot_cpu_data.x86_vendor) {
  94         case X86_VENDOR_INTEL:
  95                 rdmsr_on_cpu(cpu, MSR_IA32_MISC_ENABLE, &lo, &hi);
  96                 msr = lo | ((u64)hi << 32);
  97                 return !(msr & MSR_IA32_MISC_ENABLE_TURBO_DISABLE);
  98         case X86_VENDOR_AMD:
  99                 rdmsr_on_cpu(cpu, MSR_K7_HWCR, &lo, &hi);
 100                 msr = lo | ((u64)hi << 32);
 101                 return !(msr & MSR_K7_HWCR_CPB_DIS);
 102         }
 103         return false;
 104 }
 105
 106 static int boost_set_msr(bool enable)
 107 {
 108         u32 msr_addr;
 109         u64 msr_mask, val;
 110
 111         switch (boot_cpu_data.x86_vendor) {
 112         case X86_VENDOR_INTEL:
 113                 msr_addr = MSR_IA32_MISC_ENABLE;
 114                 msr_mask = MSR_IA32_MISC_ENABLE_TURBO_DISABLE;
 115                 break;
 116         case X86_VENDOR_AMD:
 117                 msr_addr = MSR_K7_HWCR;
 118                 msr_mask = MSR_K7_HWCR_CPB_DIS;
 119                 break;
 120         default:
 121                 return -EINVAL;
 122         }
 123
 124         rdmsrl(msr_addr, val);
 125
 126         if (enable)
 127                 val &= ~msr_mask;
 128         else
 129                 val |= msr_mask;
 130
 131         wrmsrl(msr_addr, val);
 132         return 0;
 133 }
 134
 135 static void boost_set_msr_each(void *p_en)
 136 {
 137         bool enable = (bool) p_en;
 138
 139         boost_set_msr(enable);
 140 }
 141
 142 static int set_boost(int val)
 143 {
 144         get_online_cpus();
 145         on_each_cpu(boost_set_msr_each, (void *)(long)val, 1);
 146         put_online_cpus();
 147         pr_debug("Core Boosting %sabled.\n", val ? "en" : "dis");
 148
 149         return 0;
 150 }
 151
 152 static ssize_t show_freqdomain_cpus(struct cpufreq_policy *policy, char *buf)
 153 {
 154         struct acpi_cpufreq_data *data = policy->driver_data;
 155
 156         if (unlikely(!data))
 157                 return -ENODEV;
 158
 159         return cpufreq_show_cpus(data->freqdomain_cpus, buf);
 160 }
 161
 162 cpufreq_freq_attr_ro(freqdomain_cpus);
 163
 164 #ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
 165 static ssize_t store_cpb(struct cpufreq_policy *policy, const char *buf,
 166                          size_t count)
 167 {
 168         int ret;
 169         unsigned int val = 0;
 170
 171         if (!acpi_cpufreq_driver.set_boost)
 172                 return -EINVAL;
 173
 174         ret = kstrtouint(buf, 10, &val);
 175         if (ret || val > 1)
 176                 return -EINVAL;
 177
 178         set_boost(val);
 179
 180         return count;
 181 }
 182
 183 static ssize_t show_cpb(struct cpufreq_policy *policy, char *buf)
 184 {
 185         return sprintf(buf, "%u\n", acpi_cpufreq_driver.boost_enabled);
 186 }
 187
 188 cpufreq_freq_attr_rw(cpb);
 189 #endif
 190
 191 static int check_est_cpu(unsigned int cpuid)
 192 {
 193         struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
 194
 195         return cpu_has(cpu, X86_FEATURE_EST);
 196 }
 197
 198 static int check_amd_hwpstate_cpu(unsigned int cpuid)
 199 {
 200         struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
 201
 202         return cpu_has(cpu, X86_FEATURE_HW_PSTATE);
 203 }
 204
 205 static unsigned extract_io(struct cpufreq_policy *policy, u32 value)
 206 {
 207         struct acpi_cpufreq_data *data = policy->driver_data;
 208         struct acpi_processor_performance *perf;
 209         int i;
 210
 211         perf = to_perf_data(data);
 212
 213         for (i = 0; i < perf->state_count; i++) {
 214                 if (value == perf->states[i].status)
 215                         return policy->freq_table[i].frequency;
 216         }
 217         return 0;
 218 }
 219
 220 static unsigned extract_msr(struct cpufreq_policy *policy, u32 msr)
 221 {
 222         struct acpi_cpufreq_data *data = policy->driver_data;
 223         struct cpufreq_frequency_table *pos;
 224         struct acpi_processor_performance *perf;
 225
 226         if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
 227                 msr &= AMD_MSR_RANGE;
 228         else
 229                 msr &= INTEL_MSR_RANGE;
 230
 231         perf = to_perf_data(data);
 232
 233         cpufreq_for_each_entry(pos, policy->freq_table)
 234                 if (msr == perf->states[pos->driver_data].status)
 235                         return pos->frequency;
 236         return policy->freq_table[0].frequency;
 237 }
 238
 239 static unsigned extract_freq(struct cpufreq_policy *policy, u32 val)
 240 {
 241         struct acpi_cpufreq_data *data = policy->driver_data;
 242
 243         switch (data->cpu_feature) {
 244         case SYSTEM_INTEL_MSR_CAPABLE:
 245         case SYSTEM_AMD_MSR_CAPABLE:
 246                 return extract_msr(policy, val);
 247         case SYSTEM_IO_CAPABLE:
 248                 return extract_io(policy, val);
 249         default:
 250                 return 0;
 251         }
 252 }
 253
 254 static u32 cpu_freq_read_intel(struct acpi_pct_register *not_used)
 255 {
 256         u32 val, dummy;
 257
 258         rdmsr(MSR_IA32_PERF_CTL, val, dummy);
 259         return val;
 260 }
 261
 262 static void cpu_freq_write_intel(struct acpi_pct_register *not_used, u32 val)
 263 {
 264         u32 lo, hi;
 265
 266         rdmsr(MSR_IA32_PERF_CTL, lo, hi);
 267         lo = (lo & ~INTEL_MSR_RANGE) | (val & INTEL_MSR_RANGE);
 268         wrmsr(MSR_IA32_PERF_CTL, lo, hi);
 269 }
 270
 271 static u32 cpu_freq_read_amd(struct acpi_pct_register *not_used)
 272 {
 273         u32 val, dummy;
 274
 275         rdmsr(MSR_AMD_PERF_CTL, val, dummy);
 276         return val;
 277 }
 278
 279 static void cpu_freq_write_amd(struct acpi_pct_register *not_used, u32 val)
 280 {
 281         wrmsr(MSR_AMD_PERF_CTL, val, 0);
 282 }
 283
 284 static u32 cpu_freq_read_io(struct acpi_pct_register *reg)
 285 {
 286         u32 val;
 287
 288         acpi_os_read_port(reg->address, &val, reg->bit_width);
 289         return val;
 290 }
 291
 292 static void cpu_freq_write_io(struct acpi_pct_register *reg, u32 val)
 293 {
 294         acpi_os_write_port(reg->address, val, reg->bit_width);
 295 }
 296
 297 struct drv_cmd {
 298         struct acpi_pct_register *reg;
 299         u32 val;
 300         union {
 301                 void (*write)(struct acpi_pct_register *reg, u32 val);
 302                 u32 (*read)(struct acpi_pct_register *reg);
 303         } func;
 304 };
 305
 306 /* Called via smp_call_function_single(), on the target CPU */
 307 static void do_drv_read(void *_cmd)
 308 {
 309         struct drv_cmd *cmd = _cmd;
 310
 311         cmd->val = cmd->func.read(cmd->reg);
 312 }
 313
 314 static u32 drv_read(struct acpi_cpufreq_data *data, const struct cpumask *mask)
 315 {
 316         struct acpi_processor_performance *perf = to_perf_data(data);
 317         struct drv_cmd cmd = {
 318                 .reg = &perf->control_register,
 319                 .func.read = data->cpu_freq_read,
 320         };
 321         int err;
 322
 323         err = smp_call_function_any(mask, do_drv_read, &cmd, 1);
 324         WARN_ON_ONCE(err);      /* smp_call_function_any() was buggy? */
 325         return cmd.val;
 326 }
 327
 328 /* Called via smp_call_function_many(), on the target CPUs */
 329 static void do_drv_write(void *_cmd)
 330 {
 331         struct drv_cmd *cmd = _cmd;
 332
 333         cmd->func.write(cmd->reg, cmd->val);
 334 }
 335
 336 static void drv_write(struct acpi_cpufreq_data *data,
 337                       const struct cpumask *mask, u32 val)
 338 {
 339         struct acpi_processor_performance *perf = to_perf_data(data);
 340         struct drv_cmd cmd = {
 341                 .reg = &perf->control_register,
 342                 .val = val,
 343                 .func.write = data->cpu_freq_write,
 344         };
 345         int this_cpu;
 346
 347         this_cpu = get_cpu();
 348         if (cpumask_test_cpu(this_cpu, mask))
 349                 do_drv_write(&cmd);
 350
 351         smp_call_function_many(mask, do_drv_write, &cmd, 1);
 352         put_cpu();
 353 }
 354
 355 static u32 get_cur_val(const struct cpumask *mask, struct acpi_cpufreq_data *data)
 356 {
 357         u32 val;
 358
 359         if (unlikely(cpumask_empty(mask)))
 360                 return 0;
 361
 362         val = drv_read(data, mask);
 363
 364         pr_debug("get_cur_val = %u\n", val);
 365
 366         return val;
 367 }
 368
 369 static unsigned int get_cur_freq_on_cpu(unsigned int cpu)
 370 {
 371         struct acpi_cpufreq_data *data;
 372         struct cpufreq_policy *policy;
 373         unsigned int freq;
 374         unsigned int cached_freq;
 375
 376         pr_debug("get_cur_freq_on_cpu (%d)\n", cpu);
 377
 378         policy = cpufreq_cpu_get_raw(cpu);
 379         if (unlikely(!policy))
 380                 return 0;
 381
 382         data = policy->driver_data;
 383         if (unlikely(!data || !policy->freq_table))
 384                 return 0;
 385
 386         cached_freq = policy->freq_table[to_perf_data(data)->state].frequency;
 387         freq = extract_freq(policy, get_cur_val(cpumask_of(cpu), data));
 388         if (freq != cached_freq) {
 389                 /*
 390                  * The dreaded BIOS frequency change behind our back.
 391                  * Force set the frequency on next target call.
 392                  */
 393                 data->resume = 1;
 394         }
 395
 396         pr_debug("cur freq = %u\n", freq);
 397
 398         return freq;
 399 }
 400
 401 static unsigned int check_freqs(struct cpufreq_policy *policy,
 402                                 const struct cpumask *mask, unsigned int freq)
 403 {
 404         struct acpi_cpufreq_data *data = policy->driver_data;
 405         unsigned int cur_freq;
 406         unsigned int i;
 407
 408         for (i = 0; i < 100; i++) {
 409                 cur_freq = extract_freq(policy, get_cur_val(mask, data));
 410                 if (cur_freq == freq)
 411                         return 1;
 412                 udelay(10);
 413         }
 414         return 0;
 415 }
 416
 417 static int acpi_cpufreq_target(struct cpufreq_policy *policy,
 418                                unsigned int index)
 419 {
 420         struct acpi_cpufreq_data *data = policy->driver_data;
 421         struct acpi_processor_performance *perf;
 422         const struct cpumask *mask;
 423         unsigned int next_perf_state = 0; /* Index into perf table */
 424         int result = 0;
 425
 426         if (unlikely(!data)) {
 427                 return -ENODEV;
 428         }
 429
 430         perf = to_perf_data(data);
 431         next_perf_state = policy->freq_table[index].driver_data;
 432         if (perf->state == next_perf_state) {
 433                 if (unlikely(data->resume)) {
 434                         pr_debug("Called after resume, resetting to P%d\n",
 435                                 next_perf_state);
 436                         data->resume = 0;
 437                 } else {
 438                         pr_debug("Already at target state (P%d)\n",
 439                                 next_perf_state);
 440                         return 0;
 441                 }
 442         }
 443
 444         /*
 445          * The core won't allow CPUs to go away until the governor has been
 446          * stopped, so we can rely on the stability of policy->cpus.
 447          */
 448         mask = policy->shared_type == CPUFREQ_SHARED_TYPE_ANY ?
 449                 cpumask_of(policy->cpu) : policy->cpus;
 450
 451         drv_write(data, mask, perf->states[next_perf_state].control);
 452
 453         if (acpi_pstate_strict) {
 454                 if (!check_freqs(policy, mask,
 455                                  policy->freq_table[index].frequency)) {
 456                         pr_debug("acpi_cpufreq_target failed (%d)\n",
 457                                 policy->cpu);
 458                         result = -EAGAIN;
 459                 }
 460         }
 461
 462         if (!result)
 463                 perf->state = next_perf_state;
 464
 465         return result;
 466 }
 467
 468 unsigned int acpi_cpufreq_fast_switch(struct cpufreq_policy *policy,
 469                                       unsigned int target_freq)
 470 {
 471         struct acpi_cpufreq_data *data = policy->driver_data;
 472         struct acpi_processor_performance *perf;
 473         struct cpufreq_frequency_table *entry;
 474         unsigned int next_perf_state, next_freq, index;
 475
 476         /*
 477          * Find the closest frequency above target_freq.
 478          */
 479         if (policy->cached_target_freq == target_freq)
 480                 index = policy->cached_resolved_idx;
 481         else
 482                 index = cpufreq_table_find_index_dl(policy, target_freq);
 483
 484         entry = &policy->freq_table[index];
 485         next_freq = entry->frequency;
 486         next_perf_state = entry->driver_data;
 487
 488         perf = to_perf_data(data);
 489         if (perf->state == next_perf_state) {
 490                 if (unlikely(data->resume))
 491                         data->resume = 0;
 492                 else
 493                         return next_freq;
 494         }
 495
 496         data->cpu_freq_write(&perf->control_register,
 497                              perf->states[next_perf_state].control);
 498         perf->state = next_perf_state;
 499         return next_freq;
 500 }
 501
 502 static unsigned long
 503 acpi_cpufreq_guess_freq(struct acpi_cpufreq_data *data, unsigned int cpu)
 504 {
 505         struct acpi_processor_performance *perf;
 506
 507         perf = to_perf_data(data);
 508         if (cpu_khz) {
 509                 /* search the closest match to cpu_khz */
 510                 unsigned int i;
 511                 unsigned long freq;
 512                 unsigned long freqn = perf->states[0].core_frequency * 1000;
 513
 514                 for (i = 0; i < (perf->state_count-1); i++) {
 515                         freq = freqn;
 516                         freqn = perf->states[i+1].core_frequency * 1000;
 517                         if ((2 * cpu_khz) > (freqn + freq)) {
 518                                 perf->state = i;
 519                                 return freq;
 520                         }
 521                 }
 522                 perf->state = perf->state_count-1;
 523                 return freqn;
 524         } else {
 525                 /* assume CPU is at P0... */
 526                 perf->state = 0;
 527                 return perf->states[0].core_frequency * 1000;
 528         }
 529 }
 530
 531 static void free_acpi_perf_data(void)
 532 {
 533         unsigned int i;
 534
 535         /* Freeing a NULL pointer is OK, and alloc_percpu zeroes. */
 536         for_each_possible_cpu(i)
 537                 free_cpumask_var(per_cpu_ptr(acpi_perf_data, i)
 538                                  ->shared_cpu_map);
 539         free_percpu(acpi_perf_data);
 540 }
 541
 542 static int cpufreq_boost_online(unsigned int cpu)
 543 {
 544         /*
 545          * On the CPU_UP path we simply keep the boost-disable flag
 546          * in sync with the current global state.
 547          */
 548         return boost_set_msr(acpi_cpufreq_driver.boost_enabled);
 549 }
 550
 551 static int cpufreq_boost_down_prep(unsigned int cpu)
 552 {
 553         /*
 554          * Clear the boost-disable bit on the CPU_DOWN path so that
 555          * this cpu cannot block the remaining ones from boosting.
 556          */
 557         return boost_set_msr(1);
 558 }
 559
 560 /*
 561  * acpi_cpufreq_early_init - initialize ACPI P-States library
 562  *
 563  * Initialize the ACPI P-States library (drivers/acpi/processor_perflib.c)
 564  * in order to determine correct frequency and voltage pairings. We can
 565  * do _PDC and _PSD and find out the processor dependency for the
 566  * actual init that will happen later...
 567  */
 568 static int __init acpi_cpufreq_early_init(void)
 569 {
 570         unsigned int i;
 571         pr_debug("acpi_cpufreq_early_init\n");
 572
 573         acpi_perf_data = alloc_percpu(struct acpi_processor_performance);
 574         if (!acpi_perf_data) {
 575                 pr_debug("Memory allocation error for acpi_perf_data.\n");
 576                 return -ENOMEM;
 577         }
 578         for_each_possible_cpu(i) {
 579                 if (!zalloc_cpumask_var_node(
 580                         &per_cpu_ptr(acpi_perf_data, i)->shared_cpu_map,
 581                         GFP_KERNEL, cpu_to_node(i))) {
 582
 583                         /* Freeing a NULL pointer is OK: alloc_percpu zeroes. */
 584                         free_acpi_perf_data();
 585                         return -ENOMEM;
 586                 }
 587         }
 588
 589         /* Do initialization in ACPI core */
 590         acpi_processor_preregister_performance(acpi_perf_data);
 591         return 0;
 592 }
 593
 594 #ifdef CONFIG_SMP
 595 /*
 596  * Some BIOSes do SW_ANY coordination internally, either set it up in hw
 597  * or do it in BIOS firmware and won't inform about it to OS. If not
 598  * detected, this has a side effect of making CPU run at a different speed
 599  * than OS intended it to run at. Detect it and handle it cleanly.
 600  */
 601 static int bios_with_sw_any_bug;
 602
 603 static int sw_any_bug_found(const struct dmi_system_id *d)
 604 {
 605         bios_with_sw_any_bug = 1;
 606         return 0;
 607 }
 608
 609 static const struct dmi_system_id sw_any_bug_dmi_table[] = {
 610         {
 611                 .callback = sw_any_bug_found,
 612                 .ident = "Supermicro Server X6DLP",
 613                 .matches = {
 614                         DMI_MATCH(DMI_SYS_VENDOR, "Supermicro"),
 615                         DMI_MATCH(DMI_BIOS_VERSION, "080010"),
 616                         DMI_MATCH(DMI_PRODUCT_NAME, "X6DLP"),
 617                 },
 618         },
 619         { }
 620 };
 621
 622 static int acpi_cpufreq_blacklist(struct cpuinfo_x86 *c)
 623 {
 624         /* Intel Xeon Processor 7100 Series Specification Update
 625          * http://www.intel.com/Assets/PDF/specupdate/314554.pdf
 626          * AL30: A Machine Check Exception (MCE) Occurring during an
 627          * Enhanced Intel SpeedStep Technology Ratio Change May Cause
 628          * Both Processor Cores to Lock Up. */
 629         if (c->x86_vendor == X86_VENDOR_INTEL) {
 630                 if ((c->x86 == 15) &&
 631                     (c->x86_model == 6) &&
 632                     (c->x86_stepping == 8)) {
 633                         pr_info("Intel(R) Xeon(R) 7100 Errata AL30, processors may lock up on frequency changes: disabling acpi-cpufreq\n");
 634                         return -ENODEV;
 635                     }
 636                 }
 637         return 0;
 638 }
 639 #endif
 640
 641 static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
 642 {
 643         unsigned int i;
 644         unsigned int valid_states = 0;
 645         unsigned int cpu = policy->cpu;
 646         struct acpi_cpufreq_data *data;
 647         unsigned int result = 0;
 648         struct cpuinfo_x86 *c = &cpu_data(policy->cpu);
 649         struct acpi_processor_performance *perf;
 650         struct cpufreq_frequency_table *freq_table;
 651 #ifdef CONFIG_SMP
 652         static int blacklisted;
 653 #endif
 654
 655         pr_debug("acpi_cpufreq_cpu_init\n");
 656
 657 #ifdef CONFIG_SMP
 658         if (blacklisted)
 659                 return blacklisted;
 660         blacklisted = acpi_cpufreq_blacklist(c);
 661         if (blacklisted)
 662                 return blacklisted;
 663 #endif
 664
 665         data = kzalloc(sizeof(*data), GFP_KERNEL);
 666         if (!data)
 667                 return -ENOMEM;
 668
 669         if (!zalloc_cpumask_var(&data->freqdomain_cpus, GFP_KERNEL)) {
 670                 result = -ENOMEM;
 671                 goto err_free;
 672         }
 673
 674         perf = per_cpu_ptr(acpi_perf_data, cpu);
 675         data->acpi_perf_cpu = cpu;
 676         policy->driver_data = data;
 677
 678         if (cpu_has(c, X86_FEATURE_CONSTANT_TSC))
 679                 acpi_cpufreq_driver.flags |= CPUFREQ_CONST_LOOPS;
 680
 681         result = acpi_processor_register_performance(perf, cpu);
 682         if (result)
 683                 goto err_free_mask;
 684
 685         policy->shared_type = perf->shared_type;
 686
 687         /*
 688          * Will let policy->cpus know about dependency only when software
 689          * coordination is required.
 690          */
 691         if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL ||
 692             policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {
 693                 cpumask_copy(policy->cpus, perf->shared_cpu_map);
 694         }
 695         cpumask_copy(data->freqdomain_cpus, perf->shared_cpu_map);
 696
 697 #ifdef CONFIG_SMP
 698         dmi_check_system(sw_any_bug_dmi_table);
 699         if (bios_with_sw_any_bug && !policy_is_shared(policy)) {
 700                 policy->shared_type = CPUFREQ_SHARED_TYPE_ALL;
 701                 cpumask_copy(policy->cpus, topology_core_cpumask(cpu));
 702         }
 703
 704         if (check_amd_hwpstate_cpu(cpu) && boot_cpu_data.x86 < 0x19 &&
 705             !acpi_pstate_strict) {
 706                 cpumask_clear(policy->cpus);
 707                 cpumask_set_cpu(cpu, policy->cpus);
 708                 cpumask_copy(data->freqdomain_cpus,
 709                              topology_sibling_cpumask(cpu));
 710                 policy->shared_type = CPUFREQ_SHARED_TYPE_HW;
 711                 pr_info_once("overriding BIOS provided _PSD data\n");
 712         }
 713 #endif
 714
 715         /* capability check */
 716         if (perf->state_count <= 1) {
 717                 pr_debug("No P-States\n");
 718                 result = -ENODEV;
 719                 goto err_unreg;
 720         }
 721
 722         if (perf->control_register.space_id != perf->status_register.space_id) {
 723                 result = -ENODEV;
 724                 goto err_unreg;
 725         }
 726
 727         switch (perf->control_register.space_id) {
 728         case ACPI_ADR_SPACE_SYSTEM_IO:
 729                 if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
 730                     boot_cpu_data.x86 == 0xf) {
 731                         pr_debug("AMD K8 systems must use native drivers.\n");
 732                         result = -ENODEV;
 733                         goto err_unreg;
 734                 }
 735                 pr_debug("SYSTEM IO addr space\n");
 736                 data->cpu_feature = SYSTEM_IO_CAPABLE;
 737                 data->cpu_freq_read = cpu_freq_read_io;
 738                 data->cpu_freq_write = cpu_freq_write_io;
 739                 break;
 740         case ACPI_ADR_SPACE_FIXED_HARDWARE:
 741                 pr_debug("HARDWARE addr space\n");
 742                 if (check_est_cpu(cpu)) {
 743                         data->cpu_feature = SYSTEM_INTEL_MSR_CAPABLE;
 744                         data->cpu_freq_read = cpu_freq_read_intel;
 745                         data->cpu_freq_write = cpu_freq_write_intel;
 746                         break;
 747                 }
 748                 if (check_amd_hwpstate_cpu(cpu)) {
 749                         data->cpu_feature = SYSTEM_AMD_MSR_CAPABLE;
 750                         data->cpu_freq_read = cpu_freq_read_amd;
 751                         data->cpu_freq_write = cpu_freq_write_amd;
 752                         break;
 753                 }
 754                 result = -ENODEV;
 755                 goto err_unreg;
 756         default:
 757                 pr_debug("Unknown addr space %d\n",
 758                         (u32) (perf->control_register.space_id));
 759                 result = -ENODEV;
 760                 goto err_unreg;
 761         }
 762
 763         freq_table = kzalloc(sizeof(*freq_table) *
 764                     (perf->state_count+1), GFP_KERNEL);
 765         if (!freq_table) {
 766                 result = -ENOMEM;
 767                 goto err_unreg;
 768         }
 769
 770         /* detect transition latency */
 771         policy->cpuinfo.transition_latency = 0;
 772         for (i = 0; i < perf->state_count; i++) {
 773                 if ((perf->states[i].transition_latency * 1000) >
 774                     policy->cpuinfo.transition_latency)
 775                         policy->cpuinfo.transition_latency =
 776                             perf->states[i].transition_latency * 1000;
 777         }
 778
 779         /* Check for high latency (>20uS) from buggy BIOSes, like on T42 */
 780         if (perf->control_register.space_id == ACPI_ADR_SPACE_FIXED_HARDWARE &&
 781             policy->cpuinfo.transition_latency > 20 * 1000) {
 782                 policy->cpuinfo.transition_latency = 20 * 1000;
 783                 pr_info_once("P-state transition latency capped at 20 uS\n");
 784         }
 785
 786         /* table init */
 787         for (i = 0; i < perf->state_count; i++) {
 788                 if (i > 0 && perf->states[i].core_frequency >=
 789                     freq_table[valid_states-1].frequency / 1000)
 790                         continue;
 791
 792                 freq_table[valid_states].driver_data = i;
 793                 freq_table[valid_states].frequency =
 794                     perf->states[i].core_frequency * 1000;
 795                 valid_states++;
 796         }
 797         freq_table[valid_states].frequency = CPUFREQ_TABLE_END;
 798         perf->state = 0;
 799
 800         result = cpufreq_table_validate_and_show(policy, freq_table);
 801         if (result)
 802                 goto err_freqfree;
 803
 804         if (perf->states[0].core_frequency * 1000 != policy->cpuinfo.max_freq)
 805                 pr_warn(FW_WARN "P-state 0 is not max freq\n");
 806
 807         switch (perf->control_register.space_id) {
 808         case ACPI_ADR_SPACE_SYSTEM_IO:
 809                 /*
 810                  * The core will not set policy->cur, because
 811                  * cpufreq_driver->get is NULL, so we need to set it here.
 812                  * However, we have to guess it, because the current speed is
 813                  * unknown and not detectable via IO ports.
 814                  */
 815                 policy->cur = acpi_cpufreq_guess_freq(data, policy->cpu);
 816                 break;
 817         case ACPI_ADR_SPACE_FIXED_HARDWARE:
 818                 acpi_cpufreq_driver.get = get_cur_freq_on_cpu;
 819                 break;
 820         default:
 821                 break;
 822         }
 823
 824         /* notify BIOS that we exist */
 825         acpi_processor_notify_smm(THIS_MODULE);
 826
 827         pr_debug("CPU%u - ACPI performance management activated.\n", cpu);
 828         for (i = 0; i < perf->state_count; i++)
 829                 pr_debug("     %cP%d: %d MHz, %d mW, %d uS\n",
 830                         (i == perf->state ? '*' : ' '), i,
 831                         (u32) perf->states[i].core_frequency,
 832                         (u32) perf->states[i].power,
 833                         (u32) perf->states[i].transition_latency);
 834
 835         /*
 836          * the first call to ->target() should result in us actually
 837          * writing something to the appropriate registers.
 838          */
 839         data->resume = 1;
 840
 841         policy->fast_switch_possible = !acpi_pstate_strict &&
 842                 !(policy_is_shared(policy) && policy->shared_type != CPUFREQ_SHARED_TYPE_ANY);
 843
 844         return result;
 845
 846 err_freqfree:
 847         kfree(freq_table);
 848 err_unreg:
 849         acpi_processor_unregister_performance(cpu);
 850 err_free_mask:
 851         free_cpumask_var(data->freqdomain_cpus);
 852 err_free:
 853         kfree(data);
 854         policy->driver_data = NULL;
 855
 856         return result;
 857 }
 858
 859 static int acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy)
 860 {
 861         struct acpi_cpufreq_data *data = policy->driver_data;
 862
 863         pr_debug("acpi_cpufreq_cpu_exit\n");
 864
 865         policy->fast_switch_possible = false;
 866         policy->driver_data = NULL;
 867         acpi_processor_unregister_performance(data->acpi_perf_cpu);
 868         free_cpumask_var(data->freqdomain_cpus);
 869         kfree(policy->freq_table);
 870         kfree(data);
 871
 872         return 0;
 873 }
 874
 875 static int acpi_cpufreq_resume(struct cpufreq_policy *policy)
 876 {
 877         struct acpi_cpufreq_data *data = policy->driver_data;
 878
 879         pr_debug("acpi_cpufreq_resume\n");
 880
 881         data->resume = 1;
 882
 883         return 0;
 884 }
 885
 886 static struct freq_attr *acpi_cpufreq_attr[] = {
 887         &cpufreq_freq_attr_scaling_available_freqs,
 888         &freqdomain_cpus,
 889 #ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
 890         &cpb,
 891 #endif
 892         NULL,
 893 };
 894
 895 static struct cpufreq_driver acpi_cpufreq_driver = {
 896         .verify         = cpufreq_generic_frequency_table_verify,
 897         .target_index   = acpi_cpufreq_target,
 898         .fast_switch    = acpi_cpufreq_fast_switch,
 899         .bios_limit     = acpi_processor_get_bios_limit,
 900         .init           = acpi_cpufreq_cpu_init,
 901         .exit           = acpi_cpufreq_cpu_exit,
 902         .resume         = acpi_cpufreq_resume,
 903         .name           = "acpi-cpufreq",
 904         .attr           = acpi_cpufreq_attr,
 905 };
 906
 907 static enum cpuhp_state acpi_cpufreq_online;
 908
 909 static void __init acpi_cpufreq_boost_init(void)
 910 {
 911         int ret;
 912
 913         if (!(boot_cpu_has(X86_FEATURE_CPB) || boot_cpu_has(X86_FEATURE_IDA))) {
 914                 pr_debug("Boost capabilities not present in the processor\n");
 915                 return;
 916         }
 917
 918         acpi_cpufreq_driver.set_boost = set_boost;
 919         acpi_cpufreq_driver.boost_enabled = boost_state(0);
 920
 921         /*
 922          * This calls the online callback on all online cpu and forces all
 923          * MSRs to the same value.
 924          */
 925         ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "cpufreq/acpi:online",
 926                                 cpufreq_boost_online, cpufreq_boost_down_prep);
 927         if (ret < 0) {
 928                 pr_err("acpi_cpufreq: failed to register hotplug callbacks\n");
 929                 return;
 930         }
 931         acpi_cpufreq_online = ret;
 932 }
 933
 934 static void acpi_cpufreq_boost_exit(void)
 935 {
 936         if (acpi_cpufreq_online > 0)
 937                 cpuhp_remove_state_nocalls(acpi_cpufreq_online);
 938 }
 939
 940 static int __init acpi_cpufreq_init(void)
 941 {
 942         int ret;
 943
 944         if (acpi_disabled)
 945                 return -ENODEV;
 946
 947         /* don't keep reloading if cpufreq_driver exists */
 948         if (cpufreq_get_current_driver())
 949                 return -EEXIST;
 950
 951         pr_debug("acpi_cpufreq_init\n");
 952
 953         ret = acpi_cpufreq_early_init();
 954         if (ret)
 955                 return ret;
 956
 957 #ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
 958         /* this is a sysfs file with a strange name and an even stranger
 959          * semantic - per CPU instantiation, but system global effect.
 960          * Lets enable it only on AMD CPUs for compatibility reasons and
 961          * only if configured. This is considered legacy code, which
 962          * will probably be removed at some point in the future.
 963          */
 964         if (!check_amd_hwpstate_cpu(0)) {
 965                 struct freq_attr **attr;
 966
 967                 pr_debug("CPB unsupported, do not expose it\n");
 968
 969                 for (attr = acpi_cpufreq_attr; *attr; attr++)
 970                         if (*attr == &cpb) {
 971                                 *attr = NULL;
 972                                 break;
 973                         }
 974         }
 975 #endif
 976         acpi_cpufreq_boost_init();
 977
 978         ret = cpufreq_register_driver(&acpi_cpufreq_driver);
 979         if (ret) {
 980                 free_acpi_perf_data();
 981                 acpi_cpufreq_boost_exit();
 982         }
 983         return ret;
 984 }
 985
 986 static void __exit acpi_cpufreq_exit(void)
 987 {
 988         pr_debug("acpi_cpufreq_exit\n");
 989
 990         acpi_cpufreq_boost_exit();
 991
 992         cpufreq_unregister_driver(&acpi_cpufreq_driver);
 993
 994         free_acpi_perf_data();
 995 }
 996
 997 module_param(acpi_pstate_strict, uint, 0644);
 998 MODULE_PARM_DESC(acpi_pstate_strict,
 999         "value 0 or non-zero. non-zero -> strict ACPI checks are "
1000         "performed during frequency changes.");
1001
1002 late_initcall(acpi_cpufreq_init);
1003 module_exit(acpi_cpufreq_exit);
1004
1005 static const struct x86_cpu_id acpi_cpufreq_ids[] = {
1006         X86_FEATURE_MATCH(X86_FEATURE_ACPI),
1007         X86_FEATURE_MATCH(X86_FEATURE_HW_PSTATE),
1008         {}
1009 };
1010 MODULE_DEVICE_TABLE(x86cpu, acpi_cpufreq_ids);
1011
1012 static const struct acpi_device_id processor_device_ids[] = {
1013         {ACPI_PROCESSOR_OBJECT_HID, },
1014         {ACPI_PROCESSOR_DEVICE_HID, },
1015         {},
1016 };
1017 MODULE_DEVICE_TABLE(acpi, processor_device_ids);
1018
1019 MODULE_ALIAS("acpi");