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