drivers/cpufreq/acpi-cpufreq.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * acpi-cpufreq.c - ACPI Processor P-States Driver
   4  *
   5  *  Copyright (C) 2001, 2002 Andy Grover <[email protected]>
   6  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <[email protected]>
   7  *  Copyright (C) 2002 - 2004 Dominik Brodowski <[email protected]>
   8  *  Copyright (C) 2006       Denis Sadykov <[email protected]>
   9  */
  10
  11 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  12
  13 #include <linux/kernel.h>
  14 #include <linux/module.h>
  15 #include <linux/init.h>
  16 #include <linux/smp.h>
  17 #include <linux/sched.h>
  18 #include <linux/cpufreq.h>
  19 #include <linux/compiler.h>
  20 #include <linux/dmi.h>
  21 #include <linux/slab.h>
  22 #include <linux/string_helpers.h>
  23 #include <linux/platform_device.h>
  24
  25 #include <linux/acpi.h>
  26 #include <linux/io.h>
  27 #include <linux/delay.h>
  28 #include <linux/uaccess.h>
  29
  30 #include <acpi/processor.h>
  31 #include <acpi/cppc_acpi.h>
  32
  33 #include <asm/msr.h>
  34 #include <asm/processor.h>
  35 #include <asm/cpufeature.h>
  36 #include <asm/cpu_device_id.h>
  37
  38 MODULE_AUTHOR("Paul Diefenbaugh, Dominik Brodowski");
  39 MODULE_DESCRIPTION("ACPI Processor P-States Driver");
  40 MODULE_LICENSE("GPL");
  41
  42 enum {
  43         UNDEFINED_CAPABLE = 0,
  44         SYSTEM_INTEL_MSR_CAPABLE,
  45         SYSTEM_AMD_MSR_CAPABLE,
  46         SYSTEM_IO_CAPABLE,
  47 };
  48
  49 #define INTEL_MSR_RANGE         (0xffff)
  50 #define AMD_MSR_RANGE           (0x7)
  51 #define HYGON_MSR_RANGE         (0x7)
  52
  53 struct acpi_cpufreq_data {
  54         unsigned int resume;
  55         unsigned int cpu_feature;
  56         unsigned int acpi_perf_cpu;
  57         cpumask_var_t freqdomain_cpus;
  58         void (*cpu_freq_write)(struct acpi_pct_register *reg, u32 val);
  59         u32 (*cpu_freq_read)(struct acpi_pct_register *reg);
  60 };
  61
  62 /* acpi_perf_data is a pointer to percpu data. */
  63 static struct acpi_processor_performance __percpu *acpi_perf_data;
  64
  65 static inline struct acpi_processor_performance *to_perf_data(struct acpi_cpufreq_data *data)
  66 {
  67         return per_cpu_ptr(acpi_perf_data, data->acpi_perf_cpu);
  68 }
  69
  70 static struct cpufreq_driver acpi_cpufreq_driver;
  71
  72 static unsigned int acpi_pstate_strict;
  73
  74 static bool boost_state(unsigned int cpu)
  75 {
  76         u32 lo, hi;
  77         u64 msr;
  78
  79         switch (boot_cpu_data.x86_vendor) {
  80         case X86_VENDOR_INTEL:
  81         case X86_VENDOR_CENTAUR:
  82         case X86_VENDOR_ZHAOXIN:
  83                 rdmsr_on_cpu(cpu, MSR_IA32_MISC_ENABLE, &lo, &hi);
  84                 msr = lo | ((u64)hi << 32);
  85                 return !(msr & MSR_IA32_MISC_ENABLE_TURBO_DISABLE);
  86         case X86_VENDOR_HYGON:
  87         case X86_VENDOR_AMD:
  88                 rdmsr_on_cpu(cpu, MSR_K7_HWCR, &lo, &hi);
  89                 msr = lo | ((u64)hi << 32);
  90                 return !(msr & MSR_K7_HWCR_CPB_DIS);
  91         }
  92         return false;
  93 }
  94
  95 static int boost_set_msr(bool enable)
  96 {
  97         u32 msr_addr;
  98         u64 msr_mask, val;
  99
 100         switch (boot_cpu_data.x86_vendor) {
 101         case X86_VENDOR_INTEL:
 102         case X86_VENDOR_CENTAUR:
 103         case X86_VENDOR_ZHAOXIN:
 104                 msr_addr = MSR_IA32_MISC_ENABLE;
 105                 msr_mask = MSR_IA32_MISC_ENABLE_TURBO_DISABLE;
 106                 break;
 107         case X86_VENDOR_HYGON:
 108         case X86_VENDOR_AMD:
 109                 msr_addr = MSR_K7_HWCR;
 110                 msr_mask = MSR_K7_HWCR_CPB_DIS;
 111                 break;
 112         default:
 113                 return -EINVAL;
 114         }
 115
 116         rdmsrl(msr_addr, val);
 117
 118         if (enable)
 119                 val &= ~msr_mask;
 120         else
 121                 val |= msr_mask;
 122
 123         wrmsrl(msr_addr, val);
 124         return 0;
 125 }
 126
 127 static void boost_set_msr_each(void *p_en)
 128 {
 129         bool enable = (bool) p_en;
 130
 131         boost_set_msr(enable);
 132 }
 133
 134 static int set_boost(struct cpufreq_policy *policy, int val)
 135 {
 136         on_each_cpu_mask(policy->cpus, boost_set_msr_each,
 137                          (void *)(long)val, 1);
 138         pr_debug("CPU %*pbl: Core Boosting %s.\n",
 139                  cpumask_pr_args(policy->cpus), str_enabled_disabled(val));
 140
 141         return 0;
 142 }
 143
 144 static ssize_t show_freqdomain_cpus(struct cpufreq_policy *policy, char *buf)
 145 {
 146         struct acpi_cpufreq_data *data = policy->driver_data;
 147
 148         if (unlikely(!data))
 149                 return -ENODEV;
 150
 151         return cpufreq_show_cpus(data->freqdomain_cpus, buf);
 152 }
 153
 154 cpufreq_freq_attr_ro(freqdomain_cpus);
 155
 156 #ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
 157 static ssize_t store_cpb(struct cpufreq_policy *policy, const char *buf,
 158                          size_t count)
 159 {
 160         int ret;
 161         unsigned int val = 0;
 162
 163         if (!acpi_cpufreq_driver.set_boost)
 164                 return -EINVAL;
 165
 166         ret = kstrtouint(buf, 10, &val);
 167         if (ret || val > 1)
 168                 return -EINVAL;
 169
 170         cpus_read_lock();
 171         set_boost(policy, val);
 172         cpus_read_unlock();
 173
 174         return count;
 175 }
 176
 177 static ssize_t show_cpb(struct cpufreq_policy *policy, char *buf)
 178 {
 179         return sprintf(buf, "%u\n", acpi_cpufreq_driver.boost_enabled);
 180 }
 181
 182 cpufreq_freq_attr_rw(cpb);
 183 #endif
 184
 185 static int check_est_cpu(unsigned int cpuid)
 186 {
 187         struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
 188
 189         return cpu_has(cpu, X86_FEATURE_EST);
 190 }
 191
 192 static int check_amd_hwpstate_cpu(unsigned int cpuid)
 193 {
 194         struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
 195
 196         return cpu_has(cpu, X86_FEATURE_HW_PSTATE);
 197 }
 198
 199 static unsigned extract_io(struct cpufreq_policy *policy, u32 value)
 200 {
 201         struct acpi_cpufreq_data *data = policy->driver_data;
 202         struct acpi_processor_performance *perf;
 203         int i;
 204
 205         perf = to_perf_data(data);
 206
 207         for (i = 0; i < perf->state_count; i++) {
 208                 if (value == perf->states[i].status)
 209                         return policy->freq_table[i].frequency;
 210         }
 211         return 0;
 212 }
 213
 214 static unsigned extract_msr(struct cpufreq_policy *policy, u32 msr)
 215 {
 216         struct acpi_cpufreq_data *data = policy->driver_data;
 217         struct cpufreq_frequency_table *pos;
 218         struct acpi_processor_performance *perf;
 219
 220         if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
 221                 msr &= AMD_MSR_RANGE;
 222         else if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON)
 223                 msr &= HYGON_MSR_RANGE;
 224         else
 225                 msr &= INTEL_MSR_RANGE;
 226
 227         perf = to_perf_data(data);
 228
 229         cpufreq_for_each_entry(pos, policy->freq_table)
 230                 if (msr == perf->states[pos->driver_data].status)
 231                         return pos->frequency;
 232         return policy->freq_table[0].frequency;
 233 }
 234
 235 static unsigned extract_freq(struct cpufreq_policy *policy, u32 val)
 236 {
 237         struct acpi_cpufreq_data *data = policy->driver_data;
 238
 239         switch (data->cpu_feature) {
 240         case SYSTEM_INTEL_MSR_CAPABLE:
 241         case SYSTEM_AMD_MSR_CAPABLE:
 242                 return extract_msr(policy, val);
 243         case SYSTEM_IO_CAPABLE:
 244                 return extract_io(policy, val);
 245         default:
 246                 return 0;
 247         }
 248 }
 249
 250 static u32 cpu_freq_read_intel(struct acpi_pct_register *not_used)
 251 {
 252         u32 val, dummy __always_unused;
 253
 254         rdmsr(MSR_IA32_PERF_CTL, val, dummy);
 255         return val;
 256 }
 257
 258 static void cpu_freq_write_intel(struct acpi_pct_register *not_used, u32 val)
 259 {
 260         u32 lo, hi;
 261
 262         rdmsr(MSR_IA32_PERF_CTL, lo, hi);
 263         lo = (lo & ~INTEL_MSR_RANGE) | (val & INTEL_MSR_RANGE);
 264         wrmsr(MSR_IA32_PERF_CTL, lo, hi);
 265 }
 266
 267 static u32 cpu_freq_read_amd(struct acpi_pct_register *not_used)
 268 {
 269         u32 val, dummy __always_unused;
 270
 271         rdmsr(MSR_AMD_PERF_CTL, val, dummy);
 272         return val;
 273 }
 274
 275 static void cpu_freq_write_amd(struct acpi_pct_register *not_used, u32 val)
 276 {
 277         wrmsr(MSR_AMD_PERF_CTL, val, 0);
 278 }
 279
 280 static u32 cpu_freq_read_io(struct acpi_pct_register *reg)
 281 {
 282         u32 val;
 283
 284         acpi_os_read_port(reg->address, &val, reg->bit_width);
 285         return val;
 286 }
 287
 288 static void cpu_freq_write_io(struct acpi_pct_register *reg, u32 val)
 289 {
 290         acpi_os_write_port(reg->address, val, reg->bit_width);
 291 }
 292
 293 struct drv_cmd {
 294         struct acpi_pct_register *reg;
 295         u32 val;
 296         union {
 297                 void (*write)(struct acpi_pct_register *reg, u32 val);
 298                 u32 (*read)(struct acpi_pct_register *reg);
 299         } func;
 300 };
 301
 302 /* Called via smp_call_function_single(), on the target CPU */
 303 static void do_drv_read(void *_cmd)
 304 {
 305         struct drv_cmd *cmd = _cmd;
 306
 307         cmd->val = cmd->func.read(cmd->reg);
 308 }
 309
 310 static u32 drv_read(struct acpi_cpufreq_data *data, const struct cpumask *mask)
 311 {
 312         struct acpi_processor_performance *perf = to_perf_data(data);
 313         struct drv_cmd cmd = {
 314                 .reg = &perf->control_register,
 315                 .func.read = data->cpu_freq_read,
 316         };
 317         int err;
 318
 319         err = smp_call_function_any(mask, do_drv_read, &cmd, 1);
 320         WARN_ON_ONCE(err);      /* smp_call_function_any() was buggy? */
 321         return cmd.val;
 322 }
 323
 324 /* Called via smp_call_function_many(), on the target CPUs */
 325 static void do_drv_write(void *_cmd)
 326 {
 327         struct drv_cmd *cmd = _cmd;
 328
 329         cmd->func.write(cmd->reg, cmd->val);
 330 }
 331
 332 static void drv_write(struct acpi_cpufreq_data *data,
 333                       const struct cpumask *mask, u32 val)
 334 {
 335         struct acpi_processor_performance *perf = to_perf_data(data);
 336         struct drv_cmd cmd = {
 337                 .reg = &perf->control_register,
 338                 .val = val,
 339                 .func.write = data->cpu_freq_write,
 340         };
 341         int this_cpu;
 342
 343         this_cpu = get_cpu();
 344         if (cpumask_test_cpu(this_cpu, mask))
 345                 do_drv_write(&cmd);
 346
 347         smp_call_function_many(mask, do_drv_write, &cmd, 1);
 348         put_cpu();
 349 }
 350
 351 static u32 get_cur_val(const struct cpumask *mask, struct acpi_cpufreq_data *data)
 352 {
 353         u32 val;
 354
 355         if (unlikely(cpumask_empty(mask)))
 356                 return 0;
 357
 358         val = drv_read(data, mask);
 359
 360         pr_debug("%s = %u\n", __func__, val);
 361
 362         return val;
 363 }
 364
 365 static unsigned int get_cur_freq_on_cpu(unsigned int cpu)
 366 {
 367         struct acpi_cpufreq_data *data;
 368         struct cpufreq_policy *policy;
 369         unsigned int freq;
 370         unsigned int cached_freq;
 371
 372         pr_debug("%s (%d)\n", __func__, cpu);
 373
 374         policy = cpufreq_cpu_get_raw(cpu);
 375         if (unlikely(!policy))
 376                 return 0;
 377
 378         data = policy->driver_data;
 379         if (unlikely(!data || !policy->freq_table))
 380                 return 0;
 381
 382         cached_freq = policy->freq_table[to_perf_data(data)->state].frequency;
 383         freq = extract_freq(policy, get_cur_val(cpumask_of(cpu), data));
 384         if (freq != cached_freq) {
 385                 /*
 386                  * The dreaded BIOS frequency change behind our back.
 387                  * Force set the frequency on next target call.
 388                  */
 389                 data->resume = 1;
 390         }
 391
 392         pr_debug("cur freq = %u\n", freq);
 393
 394         return freq;
 395 }
 396
 397 static unsigned int check_freqs(struct cpufreq_policy *policy,
 398                                 const struct cpumask *mask, unsigned int freq)
 399 {
 400         struct acpi_cpufreq_data *data = policy->driver_data;
 401         unsigned int cur_freq;
 402         unsigned int i;
 403
 404         for (i = 0; i < 100; i++) {
 405                 cur_freq = extract_freq(policy, get_cur_val(mask, data));
 406                 if (cur_freq == freq)
 407                         return 1;
 408                 udelay(10);
 409         }
 410         return 0;
 411 }
 412
 413 static int acpi_cpufreq_target(struct cpufreq_policy *policy,
 414                                unsigned int index)
 415 {
 416         struct acpi_cpufreq_data *data = policy->driver_data;
 417         struct acpi_processor_performance *perf;
 418         const struct cpumask *mask;
 419         unsigned int next_perf_state = 0; /* Index into perf table */
 420         int result = 0;
 421
 422         if (unlikely(!data)) {
 423                 return -ENODEV;
 424         }
 425
 426         perf = to_perf_data(data);
 427         next_perf_state = policy->freq_table[index].driver_data;
 428         if (perf->state == next_perf_state) {
 429                 if (unlikely(data->resume)) {
 430                         pr_debug("Called after resume, resetting to P%d\n",
 431                                 next_perf_state);
 432                         data->resume = 0;
 433                 } else {
 434                         pr_debug("Already at target state (P%d)\n",
 435                                 next_perf_state);
 436                         return 0;
 437                 }
 438         }
 439
 440         /*
 441          * The core won't allow CPUs to go away until the governor has been
 442          * stopped, so we can rely on the stability of policy->cpus.
 443          */
 444         mask = policy->shared_type == CPUFREQ_SHARED_TYPE_ANY ?
 445                 cpumask_of(policy->cpu) : policy->cpus;
 446
 447         drv_write(data, mask, perf->states[next_perf_state].control);
 448
 449         if (acpi_pstate_strict) {
 450                 if (!check_freqs(policy, mask,
 451                                  policy->freq_table[index].frequency)) {
 452                         pr_debug("%s (%d)\n", __func__, policy->cpu);
 453                         result = -EAGAIN;
 454                 }
 455         }
 456
 457         if (!result)
 458                 perf->state = next_perf_state;
 459
 460         return result;
 461 }
 462
 463 static unsigned int acpi_cpufreq_fast_switch(struct cpufreq_policy *policy,
 464                                              unsigned int target_freq)
 465 {
 466         struct acpi_cpufreq_data *data = policy->driver_data;
 467         struct acpi_processor_performance *perf;
 468         struct cpufreq_frequency_table *entry;
 469         unsigned int next_perf_state, next_freq, index;
 470
 471         /*
 472          * Find the closest frequency above target_freq.
 473          */
 474         if (policy->cached_target_freq == target_freq)
 475                 index = policy->cached_resolved_idx;
 476         else
 477                 index = cpufreq_table_find_index_dl(policy, target_freq,
 478                                                     false);
 479
 480         entry = &policy->freq_table[index];
 481         next_freq = entry->frequency;
 482         next_perf_state = entry->driver_data;
 483
 484         perf = to_perf_data(data);
 485         if (perf->state == next_perf_state) {
 486                 if (unlikely(data->resume))
 487                         data->resume = 0;
 488                 else
 489                         return next_freq;
 490         }
 491
 492         data->cpu_freq_write(&perf->control_register,
 493                              perf->states[next_perf_state].control);
 494         perf->state = next_perf_state;
 495         return next_freq;
 496 }
 497
 498 static unsigned long
 499 acpi_cpufreq_guess_freq(struct acpi_cpufreq_data *data, unsigned int cpu)
 500 {
 501         struct acpi_processor_performance *perf;
 502
 503         perf = to_perf_data(data);
 504         if (cpu_khz) {
 505                 /* search the closest match to cpu_khz */
 506                 unsigned int i;
 507                 unsigned long freq;
 508                 unsigned long freqn = perf->states[0].core_frequency * 1000;
 509
 510                 for (i = 0; i < (perf->state_count-1); i++) {
 511                         freq = freqn;
 512                         freqn = perf->states[i+1].core_frequency * 1000;
 513                         if ((2 * cpu_khz) > (freqn + freq)) {
 514                                 perf->state = i;
 515                                 return freq;
 516                         }
 517                 }
 518                 perf->state = perf->state_count-1;
 519                 return freqn;
 520         } else {
 521                 /* assume CPU is at P0... */
 522                 perf->state = 0;
 523                 return perf->states[0].core_frequency * 1000;
 524         }
 525 }
 526
 527 static void free_acpi_perf_data(void)
 528 {
 529         unsigned int i;
 530
 531         /* Freeing a NULL pointer is OK, and alloc_percpu zeroes. */
 532         for_each_possible_cpu(i)
 533                 free_cpumask_var(per_cpu_ptr(acpi_perf_data, i)
 534                                  ->shared_cpu_map);
 535         free_percpu(acpi_perf_data);
 536 }
 537
 538 static int cpufreq_boost_down_prep(unsigned int cpu)
 539 {
 540         /*
 541          * Clear the boost-disable bit on the CPU_DOWN path so that
 542          * this cpu cannot block the remaining ones from boosting.
 543          */
 544         return boost_set_msr(1);
 545 }
 546
 547 /*
 548  * acpi_cpufreq_early_init - initialize ACPI P-States library
 549  *
 550  * Initialize the ACPI P-States library (drivers/acpi/processor_perflib.c)
 551  * in order to determine correct frequency and voltage pairings. We can
 552  * do _PDC and _PSD and find out the processor dependency for the
 553  * actual init that will happen later...
 554  */
 555 static int __init acpi_cpufreq_early_init(void)
 556 {
 557         unsigned int i;
 558         pr_debug("%s\n", __func__);
 559
 560         acpi_perf_data = alloc_percpu(struct acpi_processor_performance);
 561         if (!acpi_perf_data) {
 562                 pr_debug("Memory allocation error for acpi_perf_data.\n");
 563                 return -ENOMEM;
 564         }
 565         for_each_possible_cpu(i) {
 566                 if (!zalloc_cpumask_var_node(
 567                         &per_cpu_ptr(acpi_perf_data, i)->shared_cpu_map,
 568                         GFP_KERNEL, cpu_to_node(i))) {
 569
 570                         /* Freeing a NULL pointer is OK: alloc_percpu zeroes. */
 571                         free_acpi_perf_data();
 572                         return -ENOMEM;
 573                 }
 574         }
 575
 576         /* Do initialization in ACPI core */
 577         acpi_processor_preregister_performance(acpi_perf_data);
 578         return 0;
 579 }
 580
 581 #ifdef CONFIG_SMP
 582 /*
 583  * Some BIOSes do SW_ANY coordination internally, either set it up in hw
 584  * or do it in BIOS firmware and won't inform about it to OS. If not
 585  * detected, this has a side effect of making CPU run at a different speed
 586  * than OS intended it to run at. Detect it and handle it cleanly.
 587  */
 588 static int bios_with_sw_any_bug;
 589
 590 static int sw_any_bug_found(const struct dmi_system_id *d)
 591 {
 592         bios_with_sw_any_bug = 1;
 593         return 0;
 594 }
 595
 596 static const struct dmi_system_id sw_any_bug_dmi_table[] = {
 597         {
 598                 .callback = sw_any_bug_found,
 599                 .ident = "Supermicro Server X6DLP",
 600                 .matches = {
 601                         DMI_MATCH(DMI_SYS_VENDOR, "Supermicro"),
 602                         DMI_MATCH(DMI_BIOS_VERSION, "080010"),
 603                         DMI_MATCH(DMI_PRODUCT_NAME, "X6DLP"),
 604                 },
 605         },
 606         { }
 607 };
 608
 609 static int acpi_cpufreq_blacklist(struct cpuinfo_x86 *c)
 610 {
 611         /* Intel Xeon Processor 7100 Series Specification Update
 612          * https://www.intel.com/Assets/PDF/specupdate/314554.pdf
 613          * AL30: A Machine Check Exception (MCE) Occurring during an
 614          * Enhanced Intel SpeedStep Technology Ratio Change May Cause
 615          * Both Processor Cores to Lock Up. */
 616         if (c->x86_vendor == X86_VENDOR_INTEL) {
 617                 if ((c->x86 == 15) &&
 618                     (c->x86_model == 6) &&
 619                     (c->x86_stepping == 8)) {
 620                         pr_info("Intel(R) Xeon(R) 7100 Errata AL30, processors may lock up on frequency changes: disabling acpi-cpufreq\n");
 621                         return -ENODEV;
 622                     }
 623                 }
 624         return 0;
 625 }
 626 #endif
 627
 628 #ifdef CONFIG_ACPI_CPPC_LIB
 629 static u64 get_max_boost_ratio(unsigned int cpu)
 630 {
 631         struct cppc_perf_caps perf_caps;
 632         u64 highest_perf, nominal_perf;
 633         int ret;
 634
 635         if (acpi_pstate_strict)
 636                 return 0;
 637
 638         ret = cppc_get_perf_caps(cpu, &perf_caps);
 639         if (ret) {
 640                 pr_debug("CPU%d: Unable to get performance capabilities (%d)\n",
 641                          cpu, ret);
 642                 return 0;
 643         }
 644
 645         if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD) {
 646                 ret = amd_get_boost_ratio_numerator(cpu, &highest_perf);
 647                 if (ret) {
 648                         pr_debug("CPU%d: Unable to get boost ratio numerator (%d)\n",
 649                                  cpu, ret);
 650                         return 0;
 651                 }
 652         } else {
 653                 highest_perf = perf_caps.highest_perf;
 654         }
 655
 656         nominal_perf = perf_caps.nominal_perf;
 657
 658         if (!highest_perf || !nominal_perf) {
 659                 pr_debug("CPU%d: highest or nominal performance missing\n", cpu);
 660                 return 0;
 661         }
 662
 663         if (highest_perf < nominal_perf) {
 664                 pr_debug("CPU%d: nominal performance above highest\n", cpu);
 665                 return 0;
 666         }
 667
 668         return div_u64(highest_perf << SCHED_CAPACITY_SHIFT, nominal_perf);
 669 }
 670 #else
 671 static inline u64 get_max_boost_ratio(unsigned int cpu) { return 0; }
 672 #endif
 673
 674 static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
 675 {
 676         struct cpufreq_frequency_table *freq_table;
 677         struct acpi_processor_performance *perf;
 678         struct acpi_cpufreq_data *data;
 679         unsigned int cpu = policy->cpu;
 680         struct cpuinfo_x86 *c = &cpu_data(cpu);
 681         unsigned int valid_states = 0;
 682         unsigned int result = 0;
 683         u64 max_boost_ratio;
 684         unsigned int i;
 685 #ifdef CONFIG_SMP
 686         static int blacklisted;
 687 #endif
 688
 689         pr_debug("%s\n", __func__);
 690
 691 #ifdef CONFIG_SMP
 692         if (blacklisted)
 693                 return blacklisted;
 694         blacklisted = acpi_cpufreq_blacklist(c);
 695         if (blacklisted)
 696                 return blacklisted;
 697 #endif
 698
 699         data = kzalloc(sizeof(*data), GFP_KERNEL);
 700         if (!data)
 701                 return -ENOMEM;
 702
 703         if (!zalloc_cpumask_var(&data->freqdomain_cpus, GFP_KERNEL)) {
 704                 result = -ENOMEM;
 705                 goto err_free;
 706         }
 707
 708         perf = per_cpu_ptr(acpi_perf_data, cpu);
 709         data->acpi_perf_cpu = cpu;
 710         policy->driver_data = data;
 711
 712         if (cpu_has(c, X86_FEATURE_CONSTANT_TSC))
 713                 acpi_cpufreq_driver.flags |= CPUFREQ_CONST_LOOPS;
 714
 715         result = acpi_processor_register_performance(perf, cpu);
 716         if (result)
 717                 goto err_free_mask;
 718
 719         policy->shared_type = perf->shared_type;
 720
 721         /*
 722          * Will let policy->cpus know about dependency only when software
 723          * coordination is required.
 724          */
 725         if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL ||
 726             policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {
 727                 cpumask_copy(policy->cpus, perf->shared_cpu_map);
 728         }
 729         cpumask_copy(data->freqdomain_cpus, perf->shared_cpu_map);
 730
 731 #ifdef CONFIG_SMP
 732         dmi_check_system(sw_any_bug_dmi_table);
 733         if (bios_with_sw_any_bug && !policy_is_shared(policy)) {
 734                 policy->shared_type = CPUFREQ_SHARED_TYPE_ALL;
 735                 cpumask_copy(policy->cpus, topology_core_cpumask(cpu));
 736         }
 737
 738         if (check_amd_hwpstate_cpu(cpu) && boot_cpu_data.x86 < 0x19 &&
 739             !acpi_pstate_strict) {
 740                 cpumask_clear(policy->cpus);
 741                 cpumask_set_cpu(cpu, policy->cpus);
 742                 cpumask_copy(data->freqdomain_cpus,
 743                              topology_sibling_cpumask(cpu));
 744                 policy->shared_type = CPUFREQ_SHARED_TYPE_HW;
 745                 pr_info_once("overriding BIOS provided _PSD data\n");
 746         }
 747 #endif
 748
 749         /* capability check */
 750         if (perf->state_count <= 1) {
 751                 pr_debug("No P-States\n");
 752                 result = -ENODEV;
 753                 goto err_unreg;
 754         }
 755
 756         if (perf->control_register.space_id != perf->status_register.space_id) {
 757                 result = -ENODEV;
 758                 goto err_unreg;
 759         }
 760
 761         switch (perf->control_register.space_id) {
 762         case ACPI_ADR_SPACE_SYSTEM_IO:
 763                 if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
 764                     boot_cpu_data.x86 == 0xf) {
 765                         pr_debug("AMD K8 systems must use native drivers.\n");
 766                         result = -ENODEV;
 767                         goto err_unreg;
 768                 }
 769                 pr_debug("SYSTEM IO addr space\n");
 770                 data->cpu_feature = SYSTEM_IO_CAPABLE;
 771                 data->cpu_freq_read = cpu_freq_read_io;
 772                 data->cpu_freq_write = cpu_freq_write_io;
 773                 break;
 774         case ACPI_ADR_SPACE_FIXED_HARDWARE:
 775                 pr_debug("HARDWARE addr space\n");
 776                 if (check_est_cpu(cpu)) {
 777                         data->cpu_feature = SYSTEM_INTEL_MSR_CAPABLE;
 778                         data->cpu_freq_read = cpu_freq_read_intel;
 779                         data->cpu_freq_write = cpu_freq_write_intel;
 780                         break;
 781                 }
 782                 if (check_amd_hwpstate_cpu(cpu)) {
 783                         data->cpu_feature = SYSTEM_AMD_MSR_CAPABLE;
 784                         data->cpu_freq_read = cpu_freq_read_amd;
 785                         data->cpu_freq_write = cpu_freq_write_amd;
 786                         break;
 787                 }
 788                 result = -ENODEV;
 789                 goto err_unreg;
 790         default:
 791                 pr_debug("Unknown addr space %d\n",
 792                         (u32) (perf->control_register.space_id));
 793                 result = -ENODEV;
 794                 goto err_unreg;
 795         }
 796
 797         freq_table = kcalloc(perf->state_count + 1, sizeof(*freq_table),
 798                              GFP_KERNEL);
 799         if (!freq_table) {
 800                 result = -ENOMEM;
 801                 goto err_unreg;
 802         }
 803
 804         /* detect transition latency */
 805         policy->cpuinfo.transition_latency = 0;
 806         for (i = 0; i < perf->state_count; i++) {
 807                 if ((perf->states[i].transition_latency * 1000) >
 808                     policy->cpuinfo.transition_latency)
 809                         policy->cpuinfo.transition_latency =
 810                             perf->states[i].transition_latency * 1000;
 811         }
 812
 813         /* Check for high latency (>20uS) from buggy BIOSes, like on T42 */
 814         if (perf->control_register.space_id == ACPI_ADR_SPACE_FIXED_HARDWARE &&
 815             policy->cpuinfo.transition_latency > 20 * 1000) {
 816                 policy->cpuinfo.transition_latency = 20 * 1000;
 817                 pr_info_once("P-state transition latency capped at 20 uS\n");
 818         }
 819
 820         /* table init */
 821         for (i = 0; i < perf->state_count; i++) {
 822                 if (i > 0 && perf->states[i].core_frequency >=
 823                     freq_table[valid_states-1].frequency / 1000)
 824                         continue;
 825
 826                 freq_table[valid_states].driver_data = i;
 827                 freq_table[valid_states].frequency =
 828                     perf->states[i].core_frequency * 1000;
 829                 valid_states++;
 830         }
 831         freq_table[valid_states].frequency = CPUFREQ_TABLE_END;
 832
 833         max_boost_ratio = get_max_boost_ratio(cpu);
 834         if (max_boost_ratio) {
 835                 unsigned int freq = freq_table[0].frequency;
 836
 837                 /*
 838                  * Because the loop above sorts the freq_table entries in the
 839                  * descending order, freq is the maximum frequency in the table.
 840                  * Assume that it corresponds to the CPPC nominal frequency and
 841                  * use it to set cpuinfo.max_freq.
 842                  */
 843                 policy->cpuinfo.max_freq = freq * max_boost_ratio >> SCHED_CAPACITY_SHIFT;
 844         } else {
 845                 /*
 846                  * If the maximum "boost" frequency is unknown, ask the arch
 847                  * scale-invariance code to use the "nominal" performance for
 848                  * CPU utilization scaling so as to prevent the schedutil
 849                  * governor from selecting inadequate CPU frequencies.
 850                  */
 851                 arch_set_max_freq_ratio(true);
 852         }
 853
 854         policy->freq_table = freq_table;
 855         perf->state = 0;
 856
 857         switch (perf->control_register.space_id) {
 858         case ACPI_ADR_SPACE_SYSTEM_IO:
 859                 /*
 860                  * The core will not set policy->cur, because
 861                  * cpufreq_driver->get is NULL, so we need to set it here.
 862                  * However, we have to guess it, because the current speed is
 863                  * unknown and not detectable via IO ports.
 864                  */
 865                 policy->cur = acpi_cpufreq_guess_freq(data, policy->cpu);
 866                 break;
 867         case ACPI_ADR_SPACE_FIXED_HARDWARE:
 868                 acpi_cpufreq_driver.get = get_cur_freq_on_cpu;
 869                 break;
 870         default:
 871                 break;
 872         }
 873
 874         /* notify BIOS that we exist */
 875         acpi_processor_notify_smm(THIS_MODULE);
 876
 877         pr_debug("CPU%u - ACPI performance management activated.\n", cpu);
 878         for (i = 0; i < perf->state_count; i++)
 879                 pr_debug("     %cP%d: %d MHz, %d mW, %d uS\n",
 880                         (i == perf->state ? '*' : ' '), i,
 881                         (u32) perf->states[i].core_frequency,
 882                         (u32) perf->states[i].power,
 883                         (u32) perf->states[i].transition_latency);
 884
 885         /*
 886          * the first call to ->target() should result in us actually
 887          * writing something to the appropriate registers.
 888          */
 889         data->resume = 1;
 890
 891         policy->fast_switch_possible = !acpi_pstate_strict &&
 892                 !(policy_is_shared(policy) && policy->shared_type != CPUFREQ_SHARED_TYPE_ANY);
 893
 894         if (perf->states[0].core_frequency * 1000 != freq_table[0].frequency)
 895                 pr_warn(FW_WARN "P-state 0 is not max freq\n");
 896
 897         if (acpi_cpufreq_driver.set_boost) {
 898                 set_boost(policy, acpi_cpufreq_driver.boost_enabled);
 899                 policy->boost_enabled = acpi_cpufreq_driver.boost_enabled;
 900         }
 901
 902         return result;
 903
 904 err_unreg:
 905         acpi_processor_unregister_performance(cpu);
 906 err_free_mask:
 907         free_cpumask_var(data->freqdomain_cpus);
 908 err_free:
 909         kfree(data);
 910         policy->driver_data = NULL;
 911
 912         return result;
 913 }
 914
 915 static void acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy)
 916 {
 917         struct acpi_cpufreq_data *data = policy->driver_data;
 918
 919         pr_debug("%s\n", __func__);
 920
 921         cpufreq_boost_down_prep(policy->cpu);
 922         policy->fast_switch_possible = false;
 923         policy->driver_data = NULL;
 924         acpi_processor_unregister_performance(data->acpi_perf_cpu);
 925         free_cpumask_var(data->freqdomain_cpus);
 926         kfree(policy->freq_table);
 927         kfree(data);
 928 }
 929
 930 static int acpi_cpufreq_resume(struct cpufreq_policy *policy)
 931 {
 932         struct acpi_cpufreq_data *data = policy->driver_data;
 933
 934         pr_debug("%s\n", __func__);
 935
 936         data->resume = 1;
 937
 938         return 0;
 939 }
 940
 941 static struct freq_attr *acpi_cpufreq_attr[] = {
 942         &cpufreq_freq_attr_scaling_available_freqs,
 943         &freqdomain_cpus,
 944 #ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
 945         &cpb,
 946 #endif
 947         NULL,
 948 };
 949
 950 static struct cpufreq_driver acpi_cpufreq_driver = {
 951         .verify         = cpufreq_generic_frequency_table_verify,
 952         .target_index   = acpi_cpufreq_target,
 953         .fast_switch    = acpi_cpufreq_fast_switch,
 954         .bios_limit     = acpi_processor_get_bios_limit,
 955         .init           = acpi_cpufreq_cpu_init,
 956         .exit           = acpi_cpufreq_cpu_exit,
 957         .resume         = acpi_cpufreq_resume,
 958         .name           = "acpi-cpufreq",
 959         .attr           = acpi_cpufreq_attr,
 960 };
 961
 962 static void __init acpi_cpufreq_boost_init(void)
 963 {
 964         if (!(boot_cpu_has(X86_FEATURE_CPB) || boot_cpu_has(X86_FEATURE_IDA))) {
 965                 pr_debug("Boost capabilities not present in the processor\n");
 966                 return;
 967         }
 968
 969         acpi_cpufreq_driver.set_boost = set_boost;
 970         acpi_cpufreq_driver.boost_enabled = boost_state(0);
 971 }
 972
 973 static int __init acpi_cpufreq_probe(struct platform_device *pdev)
 974 {
 975         int ret;
 976
 977         if (acpi_disabled)
 978                 return -ENODEV;
 979
 980         /* don't keep reloading if cpufreq_driver exists */
 981         if (cpufreq_get_current_driver())
 982                 return -ENODEV;
 983
 984         pr_debug("%s\n", __func__);
 985
 986         ret = acpi_cpufreq_early_init();
 987         if (ret)
 988                 return ret;
 989
 990 #ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
 991         /* this is a sysfs file with a strange name and an even stranger
 992          * semantic - per CPU instantiation, but system global effect.
 993          * Lets enable it only on AMD CPUs for compatibility reasons and
 994          * only if configured. This is considered legacy code, which
 995          * will probably be removed at some point in the future.
 996          */
 997         if (!check_amd_hwpstate_cpu(0)) {
 998                 struct freq_attr **attr;
 999
1000                 pr_debug("CPB unsupported, do not expose it\n");
1001
1002                 for (attr = acpi_cpufreq_attr; *attr; attr++)
1003                         if (*attr == &cpb) {
1004                                 *attr = NULL;
1005                                 break;
1006                         }
1007         }
1008 #endif
1009         acpi_cpufreq_boost_init();
1010
1011         ret = cpufreq_register_driver(&acpi_cpufreq_driver);
1012         if (ret) {
1013                 free_acpi_perf_data();
1014         }
1015         return ret;
1016 }
1017
1018 static void acpi_cpufreq_remove(struct platform_device *pdev)
1019 {
1020         pr_debug("%s\n", __func__);
1021
1022         cpufreq_unregister_driver(&acpi_cpufreq_driver);
1023
1024         free_acpi_perf_data();
1025 }
1026
1027 static struct platform_driver acpi_cpufreq_platdrv = {
1028         .driver = {
1029                 .name   = "acpi-cpufreq",
1030         },
1031         .remove_new     = acpi_cpufreq_remove,
1032 };
1033
1034 static int __init acpi_cpufreq_init(void)
1035 {
1036         return platform_driver_probe(&acpi_cpufreq_platdrv, acpi_cpufreq_probe);
1037 }
1038
1039 static void __exit acpi_cpufreq_exit(void)
1040 {
1041         platform_driver_unregister(&acpi_cpufreq_platdrv);
1042 }
1043
1044 module_param(acpi_pstate_strict, uint, 0644);
1045 MODULE_PARM_DESC(acpi_pstate_strict,
1046         "value 0 or non-zero. non-zero -> strict ACPI checks are "
1047         "performed during frequency changes.");
1048
1049 late_initcall(acpi_cpufreq_init);
1050 module_exit(acpi_cpufreq_exit);
1051
1052 MODULE_ALIAS("platform:acpi-cpufreq");