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 #include <linux/kernel.h>
  29 #include <linux/module.h>
  30 #include <linux/init.h>
  31 #include <linux/smp.h>
  32 #include <linux/sched.h>
  33 #include <linux/cpufreq.h>
  34 #include <linux/compiler.h>
  35 #include <linux/dmi.h>
  36 #include <linux/slab.h>
  37
  38 #include <linux/acpi.h>
  39 #include <linux/io.h>
  40 #include <linux/delay.h>
  41 #include <linux/uaccess.h>
  42
  43 #include <acpi/processor.h>
  44
  45 #include <asm/msr.h>
  46 #include <asm/processor.h>
  47 #include <asm/cpufeature.h>
  48
  49 MODULE_AUTHOR("Paul Diefenbaugh, Dominik Brodowski");
  50 MODULE_DESCRIPTION("ACPI Processor P-States Driver");
  51 MODULE_LICENSE("GPL");
  52
  53 #define PFX "acpi-cpufreq: "
  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         struct cpufreq_frequency_table *freq_table;
  69         unsigned int resume;
  70         unsigned int cpu_feature;
  71         unsigned int acpi_perf_cpu;
  72         cpumask_var_t freqdomain_cpus;
  73         void (*cpu_freq_write)(struct acpi_pct_register *reg, u32 val);
  74         u32 (*cpu_freq_read)(struct acpi_pct_register *reg);
  75 };
  76
  77 /* acpi_perf_data is a pointer to percpu data. */
  78 static struct acpi_processor_performance __percpu *acpi_perf_data;
  79
  80 static inline struct acpi_processor_performance *to_perf_data(struct acpi_cpufreq_data *data)
  81 {
  82         return per_cpu_ptr(acpi_perf_data, data->acpi_perf_cpu);
  83 }
  84
  85 static struct cpufreq_driver acpi_cpufreq_driver;
  86
  87 static unsigned int acpi_pstate_strict;
  88 static struct msr __percpu *msrs;
  89
  90 static bool boost_state(unsigned int cpu)
  91 {
  92         u32 lo, hi;
  93         u64 msr;
  94
  95         switch (boot_cpu_data.x86_vendor) {
  96         case X86_VENDOR_INTEL:
  97                 rdmsr_on_cpu(cpu, MSR_IA32_MISC_ENABLE, &lo, &hi);
  98                 msr = lo | ((u64)hi << 32);
  99                 return !(msr & MSR_IA32_MISC_ENABLE_TURBO_DISABLE);
 100         case X86_VENDOR_AMD:
 101                 rdmsr_on_cpu(cpu, MSR_K7_HWCR, &lo, &hi);
 102                 msr = lo | ((u64)hi << 32);
 103                 return !(msr & MSR_K7_HWCR_CPB_DIS);
 104         }
 105         return false;
 106 }
 107
 108 static void boost_set_msrs(bool enable, const struct cpumask *cpumask)
 109 {
 110         u32 cpu;
 111         u32 msr_addr;
 112         u64 msr_mask;
 113
 114         switch (boot_cpu_data.x86_vendor) {
 115         case X86_VENDOR_INTEL:
 116                 msr_addr = MSR_IA32_MISC_ENABLE;
 117                 msr_mask = MSR_IA32_MISC_ENABLE_TURBO_DISABLE;
 118                 break;
 119         case X86_VENDOR_AMD:
 120                 msr_addr = MSR_K7_HWCR;
 121                 msr_mask = MSR_K7_HWCR_CPB_DIS;
 122                 break;
 123         default:
 124                 return;
 125         }
 126
 127         rdmsr_on_cpus(cpumask, msr_addr, msrs);
 128
 129         for_each_cpu(cpu, cpumask) {
 130                 struct msr *reg = per_cpu_ptr(msrs, cpu);
 131                 if (enable)
 132                         reg->q &= ~msr_mask;
 133                 else
 134                         reg->q |= msr_mask;
 135         }
 136
 137         wrmsr_on_cpus(cpumask, msr_addr, msrs);
 138 }
 139
 140 static int set_boost(int val)
 141 {
 142         get_online_cpus();
 143         boost_set_msrs(val, cpu_online_mask);
 144         put_online_cpus();
 145         pr_debug("Core Boosting %sabled.\n", val ? "en" : "dis");
 146
 147         return 0;
 148 }
 149
 150 static ssize_t show_freqdomain_cpus(struct cpufreq_policy *policy, char *buf)
 151 {
 152         struct acpi_cpufreq_data *data = policy->driver_data;
 153
 154         if (unlikely(!data))
 155                 return -ENODEV;
 156
 157         return cpufreq_show_cpus(data->freqdomain_cpus, buf);
 158 }
 159
 160 cpufreq_freq_attr_ro(freqdomain_cpus);
 161
 162 #ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
 163 static ssize_t store_cpb(struct cpufreq_policy *policy, const char *buf,
 164                          size_t count)
 165 {
 166         int ret;
 167         unsigned int val = 0;
 168
 169         if (!acpi_cpufreq_driver.set_boost)
 170                 return -EINVAL;
 171
 172         ret = kstrtouint(buf, 10, &val);
 173         if (ret || val > 1)
 174                 return -EINVAL;
 175
 176         set_boost(val);
 177
 178         return count;
 179 }
 180
 181 static ssize_t show_cpb(struct cpufreq_policy *policy, char *buf)
 182 {
 183         return sprintf(buf, "%u\n", acpi_cpufreq_driver.boost_enabled);
 184 }
 185
 186 cpufreq_freq_attr_rw(cpb);
 187 #endif
 188
 189 static int check_est_cpu(unsigned int cpuid)
 190 {
 191         struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
 192
 193         return cpu_has(cpu, X86_FEATURE_EST);
 194 }
 195
 196 static int check_amd_hwpstate_cpu(unsigned int cpuid)
 197 {
 198         struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
 199
 200         return cpu_has(cpu, X86_FEATURE_HW_PSTATE);
 201 }
 202
 203 static unsigned extract_io(u32 value, struct acpi_cpufreq_data *data)
 204 {
 205         struct acpi_processor_performance *perf;
 206         int i;
 207
 208         perf = to_perf_data(data);
 209
 210         for (i = 0; i < perf->state_count; i++) {
 211                 if (value == perf->states[i].status)
 212                         return data->freq_table[i].frequency;
 213         }
 214         return 0;
 215 }
 216
 217 static unsigned extract_msr(u32 msr, struct acpi_cpufreq_data *data)
 218 {
 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
 225                 msr &= INTEL_MSR_RANGE;
 226
 227         perf = to_perf_data(data);
 228
 229         cpufreq_for_each_entry(pos, data->freq_table)
 230                 if (msr == perf->states[pos->driver_data].status)
 231                         return pos->frequency;
 232         return data->freq_table[0].frequency;
 233 }
 234
 235 static unsigned extract_freq(u32 val, struct acpi_cpufreq_data *data)
 236 {
 237         switch (data->cpu_feature) {
 238         case SYSTEM_INTEL_MSR_CAPABLE:
 239         case SYSTEM_AMD_MSR_CAPABLE:
 240                 return extract_msr(val, data);
 241         case SYSTEM_IO_CAPABLE:
 242                 return extract_io(val, data);
 243         default:
 244                 return 0;
 245         }
 246 }
 247
 248 static u32 cpu_freq_read_intel(struct acpi_pct_register *not_used)
 249 {
 250         u32 val, dummy;
 251
 252         rdmsr(MSR_IA32_PERF_CTL, val, dummy);
 253         return val;
 254 }
 255
 256 static void cpu_freq_write_intel(struct acpi_pct_register *not_used, u32 val)
 257 {
 258         u32 lo, hi;
 259
 260         rdmsr(MSR_IA32_PERF_CTL, lo, hi);
 261         lo = (lo & ~INTEL_MSR_RANGE) | (val & INTEL_MSR_RANGE);
 262         wrmsr(MSR_IA32_PERF_CTL, lo, hi);
 263 }
 264
 265 static u32 cpu_freq_read_amd(struct acpi_pct_register *not_used)
 266 {
 267         u32 val, dummy;
 268
 269         rdmsr(MSR_AMD_PERF_CTL, val, dummy);
 270         return val;
 271 }
 272
 273 static void cpu_freq_write_amd(struct acpi_pct_register *not_used, u32 val)
 274 {
 275         wrmsr(MSR_AMD_PERF_CTL, val, 0);
 276 }
 277
 278 static u32 cpu_freq_read_io(struct acpi_pct_register *reg)
 279 {
 280         u32 val;
 281
 282         acpi_os_read_port(reg->address, &val, reg->bit_width);
 283         return val;
 284 }
 285
 286 static void cpu_freq_write_io(struct acpi_pct_register *reg, u32 val)
 287 {
 288         acpi_os_write_port(reg->address, val, reg->bit_width);
 289 }
 290
 291 struct drv_cmd {
 292         struct acpi_pct_register *reg;
 293         u32 val;
 294         union {
 295                 void (*write)(struct acpi_pct_register *reg, u32 val);
 296                 u32 (*read)(struct acpi_pct_register *reg);
 297         } func;
 298 };
 299
 300 /* Called via smp_call_function_single(), on the target CPU */
 301 static void do_drv_read(void *_cmd)
 302 {
 303         struct drv_cmd *cmd = _cmd;
 304
 305         cmd->val = cmd->func.read(cmd->reg);
 306 }
 307
 308 static u32 drv_read(struct acpi_cpufreq_data *data, const struct cpumask *mask)
 309 {
 310         struct acpi_processor_performance *perf = to_perf_data(data);
 311         struct drv_cmd cmd = {
 312                 .reg = &perf->control_register,
 313                 .func.read = data->cpu_freq_read,
 314         };
 315         int err;
 316
 317         err = smp_call_function_any(mask, do_drv_read, &cmd, 1);
 318         WARN_ON_ONCE(err);      /* smp_call_function_any() was buggy? */
 319         return cmd.val;
 320 }
 321
 322 /* Called via smp_call_function_many(), on the target CPUs */
 323 static void do_drv_write(void *_cmd)
 324 {
 325         struct drv_cmd *cmd = _cmd;
 326
 327         cmd->func.write(cmd->reg, cmd->val);
 328 }
 329
 330 static void drv_write(struct acpi_cpufreq_data *data,
 331                       const struct cpumask *mask, u32 val)
 332 {
 333         struct acpi_processor_performance *perf = to_perf_data(data);
 334         struct drv_cmd cmd = {
 335                 .reg = &perf->control_register,
 336                 .val = val,
 337                 .func.write = data->cpu_freq_write,
 338         };
 339         int this_cpu;
 340
 341         this_cpu = get_cpu();
 342         if (cpumask_test_cpu(this_cpu, mask))
 343                 do_drv_write(&cmd);
 344
 345         smp_call_function_many(mask, do_drv_write, &cmd, 1);
 346         put_cpu();
 347 }
 348
 349 static u32 get_cur_val(const struct cpumask *mask, struct acpi_cpufreq_data *data)
 350 {
 351         u32 val;
 352
 353         if (unlikely(cpumask_empty(mask)))
 354                 return 0;
 355
 356         val = drv_read(data, mask);
 357
 358         pr_debug("get_cur_val = %u\n", val);
 359
 360         return val;
 361 }
 362
 363 static unsigned int get_cur_freq_on_cpu(unsigned int cpu)
 364 {
 365         struct acpi_cpufreq_data *data;
 366         struct cpufreq_policy *policy;
 367         unsigned int freq;
 368         unsigned int cached_freq;
 369
 370         pr_debug("get_cur_freq_on_cpu (%d)\n", cpu);
 371
 372         policy = cpufreq_cpu_get_raw(cpu);
 373         if (unlikely(!policy))
 374                 return 0;
 375
 376         data = policy->driver_data;
 377         if (unlikely(!data || !data->freq_table))
 378                 return 0;
 379
 380         cached_freq = data->freq_table[to_perf_data(data)->state].frequency;
 381         freq = extract_freq(get_cur_val(cpumask_of(cpu), data), data);
 382         if (freq != cached_freq) {
 383                 /*
 384                  * The dreaded BIOS frequency change behind our back.
 385                  * Force set the frequency on next target call.
 386                  */
 387                 data->resume = 1;
 388         }
 389
 390         pr_debug("cur freq = %u\n", freq);
 391
 392         return freq;
 393 }
 394
 395 static unsigned int check_freqs(const struct cpumask *mask, unsigned int freq,
 396                                 struct acpi_cpufreq_data *data)
 397 {
 398         unsigned int cur_freq;
 399         unsigned int i;
 400
 401         for (i = 0; i < 100; i++) {
 402                 cur_freq = extract_freq(get_cur_val(mask, data), data);
 403                 if (cur_freq == freq)
 404                         return 1;
 405                 udelay(10);
 406         }
 407         return 0;
 408 }
 409
 410 static int acpi_cpufreq_target(struct cpufreq_policy *policy,
 411                                unsigned int index)
 412 {
 413         struct acpi_cpufreq_data *data = policy->driver_data;
 414         struct acpi_processor_performance *perf;
 415         const struct cpumask *mask;
 416         unsigned int next_perf_state = 0; /* Index into perf table */
 417         int result = 0;
 418
 419         if (unlikely(data == NULL || data->freq_table == NULL)) {
 420                 return -ENODEV;
 421         }
 422
 423         perf = to_perf_data(data);
 424         next_perf_state = data->freq_table[index].driver_data;
 425         if (perf->state == next_perf_state) {
 426                 if (unlikely(data->resume)) {
 427                         pr_debug("Called after resume, resetting to P%d\n",
 428                                 next_perf_state);
 429                         data->resume = 0;
 430                 } else {
 431                         pr_debug("Already at target state (P%d)\n",
 432                                 next_perf_state);
 433                         return 0;
 434                 }
 435         }
 436
 437         /*
 438          * The core won't allow CPUs to go away until the governor has been
 439          * stopped, so we can rely on the stability of policy->cpus.
 440          */
 441         mask = policy->shared_type == CPUFREQ_SHARED_TYPE_ANY ?
 442                 cpumask_of(policy->cpu) : policy->cpus;
 443
 444         drv_write(data, mask, perf->states[next_perf_state].control);
 445
 446         if (acpi_pstate_strict) {
 447                 if (!check_freqs(mask, data->freq_table[index].frequency,
 448                                         data)) {
 449                         pr_debug("acpi_cpufreq_target failed (%d)\n",
 450                                 policy->cpu);
 451                         result = -EAGAIN;
 452                 }
 453         }
 454
 455         if (!result)
 456                 perf->state = next_perf_state;
 457
 458         return result;
 459 }
 460
 461 static unsigned long
 462 acpi_cpufreq_guess_freq(struct acpi_cpufreq_data *data, unsigned int cpu)
 463 {
 464         struct acpi_processor_performance *perf;
 465
 466         perf = to_perf_data(data);
 467         if (cpu_khz) {
 468                 /* search the closest match to cpu_khz */
 469                 unsigned int i;
 470                 unsigned long freq;
 471                 unsigned long freqn = perf->states[0].core_frequency * 1000;
 472
 473                 for (i = 0; i < (perf->state_count-1); i++) {
 474                         freq = freqn;
 475                         freqn = perf->states[i+1].core_frequency * 1000;
 476                         if ((2 * cpu_khz) > (freqn + freq)) {
 477                                 perf->state = i;
 478                                 return freq;
 479                         }
 480                 }
 481                 perf->state = perf->state_count-1;
 482                 return freqn;
 483         } else {
 484                 /* assume CPU is at P0... */
 485                 perf->state = 0;
 486                 return perf->states[0].core_frequency * 1000;
 487         }
 488 }
 489
 490 static void free_acpi_perf_data(void)
 491 {
 492         unsigned int i;
 493
 494         /* Freeing a NULL pointer is OK, and alloc_percpu zeroes. */
 495         for_each_possible_cpu(i)
 496                 free_cpumask_var(per_cpu_ptr(acpi_perf_data, i)
 497                                  ->shared_cpu_map);
 498         free_percpu(acpi_perf_data);
 499 }
 500
 501 static int boost_notify(struct notifier_block *nb, unsigned long action,
 502                       void *hcpu)
 503 {
 504         unsigned cpu = (long)hcpu;
 505         const struct cpumask *cpumask;
 506
 507         cpumask = get_cpu_mask(cpu);
 508
 509         /*
 510          * Clear the boost-disable bit on the CPU_DOWN path so that
 511          * this cpu cannot block the remaining ones from boosting. On
 512          * the CPU_UP path we simply keep the boost-disable flag in
 513          * sync with the current global state.
 514          */
 515
 516         switch (action) {
 517         case CPU_DOWN_FAILED:
 518         case CPU_DOWN_FAILED_FROZEN:
 519         case CPU_ONLINE:
 520         case CPU_ONLINE_FROZEN:
 521                 boost_set_msrs(acpi_cpufreq_driver.boost_enabled, cpumask);
 522                 break;
 523
 524         case CPU_DOWN_PREPARE:
 525         case CPU_DOWN_PREPARE_FROZEN:
 526                 boost_set_msrs(1, cpumask);
 527                 break;
 528
 529         default:
 530                 break;
 531         }
 532
 533         return NOTIFY_OK;
 534 }
 535
 536
 537 static struct notifier_block boost_nb = {
 538         .notifier_call          = boost_notify,
 539 };
 540
 541 /*
 542  * acpi_cpufreq_early_init - initialize ACPI P-States library
 543  *
 544  * Initialize the ACPI P-States library (drivers/acpi/processor_perflib.c)
 545  * in order to determine correct frequency and voltage pairings. We can
 546  * do _PDC and _PSD and find out the processor dependency for the
 547  * actual init that will happen later...
 548  */
 549 static int __init acpi_cpufreq_early_init(void)
 550 {
 551         unsigned int i;
 552         pr_debug("acpi_cpufreq_early_init\n");
 553
 554         acpi_perf_data = alloc_percpu(struct acpi_processor_performance);
 555         if (!acpi_perf_data) {
 556                 pr_debug("Memory allocation error for acpi_perf_data.\n");
 557                 return -ENOMEM;
 558         }
 559         for_each_possible_cpu(i) {
 560                 if (!zalloc_cpumask_var_node(
 561                         &per_cpu_ptr(acpi_perf_data, i)->shared_cpu_map,
 562                         GFP_KERNEL, cpu_to_node(i))) {
 563
 564                         /* Freeing a NULL pointer is OK: alloc_percpu zeroes. */
 565                         free_acpi_perf_data();
 566                         return -ENOMEM;
 567                 }
 568         }
 569
 570         /* Do initialization in ACPI core */
 571         acpi_processor_preregister_performance(acpi_perf_data);
 572         return 0;
 573 }
 574
 575 #ifdef CONFIG_SMP
 576 /*
 577  * Some BIOSes do SW_ANY coordination internally, either set it up in hw
 578  * or do it in BIOS firmware and won't inform about it to OS. If not
 579  * detected, this has a side effect of making CPU run at a different speed
 580  * than OS intended it to run at. Detect it and handle it cleanly.
 581  */
 582 static int bios_with_sw_any_bug;
 583
 584 static int sw_any_bug_found(const struct dmi_system_id *d)
 585 {
 586         bios_with_sw_any_bug = 1;
 587         return 0;
 588 }
 589
 590 static const struct dmi_system_id sw_any_bug_dmi_table[] = {
 591         {
 592                 .callback = sw_any_bug_found,
 593                 .ident = "Supermicro Server X6DLP",
 594                 .matches = {
 595                         DMI_MATCH(DMI_SYS_VENDOR, "Supermicro"),
 596                         DMI_MATCH(DMI_BIOS_VERSION, "080010"),
 597                         DMI_MATCH(DMI_PRODUCT_NAME, "X6DLP"),
 598                 },
 599         },
 600         { }
 601 };
 602
 603 static int acpi_cpufreq_blacklist(struct cpuinfo_x86 *c)
 604 {
 605         /* Intel Xeon Processor 7100 Series Specification Update
 606          * http://www.intel.com/Assets/PDF/specupdate/314554.pdf
 607          * AL30: A Machine Check Exception (MCE) Occurring during an
 608          * Enhanced Intel SpeedStep Technology Ratio Change May Cause
 609          * Both Processor Cores to Lock Up. */
 610         if (c->x86_vendor == X86_VENDOR_INTEL) {
 611                 if ((c->x86 == 15) &&
 612                     (c->x86_model == 6) &&
 613                     (c->x86_mask == 8)) {
 614                         printk(KERN_INFO "acpi-cpufreq: Intel(R) "
 615                             "Xeon(R) 7100 Errata AL30, processors may "
 616                             "lock up on frequency changes: disabling "
 617                             "acpi-cpufreq.\n");
 618                         return -ENODEV;
 619                     }
 620                 }
 621         return 0;
 622 }
 623 #endif
 624
 625 static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
 626 {
 627         unsigned int i;
 628         unsigned int valid_states = 0;
 629         unsigned int cpu = policy->cpu;
 630         struct acpi_cpufreq_data *data;
 631         unsigned int result = 0;
 632         struct cpuinfo_x86 *c = &cpu_data(policy->cpu);
 633         struct acpi_processor_performance *perf;
 634 #ifdef CONFIG_SMP
 635         static int blacklisted;
 636 #endif
 637
 638         pr_debug("acpi_cpufreq_cpu_init\n");
 639
 640 #ifdef CONFIG_SMP
 641         if (blacklisted)
 642                 return blacklisted;
 643         blacklisted = acpi_cpufreq_blacklist(c);
 644         if (blacklisted)
 645                 return blacklisted;
 646 #endif
 647
 648         data = kzalloc(sizeof(*data), GFP_KERNEL);
 649         if (!data)
 650                 return -ENOMEM;
 651
 652         if (!zalloc_cpumask_var(&data->freqdomain_cpus, GFP_KERNEL)) {
 653                 result = -ENOMEM;
 654                 goto err_free;
 655         }
 656
 657         perf = per_cpu_ptr(acpi_perf_data, cpu);
 658         data->acpi_perf_cpu = cpu;
 659         policy->driver_data = data;
 660
 661         if (cpu_has(c, X86_FEATURE_CONSTANT_TSC))
 662                 acpi_cpufreq_driver.flags |= CPUFREQ_CONST_LOOPS;
 663
 664         result = acpi_processor_register_performance(perf, cpu);
 665         if (result)
 666                 goto err_free_mask;
 667
 668         policy->shared_type = perf->shared_type;
 669
 670         /*
 671          * Will let policy->cpus know about dependency only when software
 672          * coordination is required.
 673          */
 674         if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL ||
 675             policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {
 676                 cpumask_copy(policy->cpus, perf->shared_cpu_map);
 677         }
 678         cpumask_copy(data->freqdomain_cpus, perf->shared_cpu_map);
 679
 680 #ifdef CONFIG_SMP
 681         dmi_check_system(sw_any_bug_dmi_table);
 682         if (bios_with_sw_any_bug && !policy_is_shared(policy)) {
 683                 policy->shared_type = CPUFREQ_SHARED_TYPE_ALL;
 684                 cpumask_copy(policy->cpus, topology_core_cpumask(cpu));
 685         }
 686
 687         if (check_amd_hwpstate_cpu(cpu) && !acpi_pstate_strict) {
 688                 cpumask_clear(policy->cpus);
 689                 cpumask_set_cpu(cpu, policy->cpus);
 690                 cpumask_copy(data->freqdomain_cpus,
 691                              topology_sibling_cpumask(cpu));
 692                 policy->shared_type = CPUFREQ_SHARED_TYPE_HW;
 693                 pr_info_once(PFX "overriding BIOS provided _PSD data\n");
 694         }
 695 #endif
 696
 697         /* capability check */
 698         if (perf->state_count <= 1) {
 699                 pr_debug("No P-States\n");
 700                 result = -ENODEV;
 701                 goto err_unreg;
 702         }
 703
 704         if (perf->control_register.space_id != perf->status_register.space_id) {
 705                 result = -ENODEV;
 706                 goto err_unreg;
 707         }
 708
 709         switch (perf->control_register.space_id) {
 710         case ACPI_ADR_SPACE_SYSTEM_IO:
 711                 if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
 712                     boot_cpu_data.x86 == 0xf) {
 713                         pr_debug("AMD K8 systems must use native drivers.\n");
 714                         result = -ENODEV;
 715                         goto err_unreg;
 716                 }
 717                 pr_debug("SYSTEM IO addr space\n");
 718                 data->cpu_feature = SYSTEM_IO_CAPABLE;
 719                 data->cpu_freq_read = cpu_freq_read_io;
 720                 data->cpu_freq_write = cpu_freq_write_io;
 721                 break;
 722         case ACPI_ADR_SPACE_FIXED_HARDWARE:
 723                 pr_debug("HARDWARE addr space\n");
 724                 if (check_est_cpu(cpu)) {
 725                         data->cpu_feature = SYSTEM_INTEL_MSR_CAPABLE;
 726                         data->cpu_freq_read = cpu_freq_read_intel;
 727                         data->cpu_freq_write = cpu_freq_write_intel;
 728                         break;
 729                 }
 730                 if (check_amd_hwpstate_cpu(cpu)) {
 731                         data->cpu_feature = SYSTEM_AMD_MSR_CAPABLE;
 732                         data->cpu_freq_read = cpu_freq_read_amd;
 733                         data->cpu_freq_write = cpu_freq_write_amd;
 734                         break;
 735                 }
 736                 result = -ENODEV;
 737                 goto err_unreg;
 738         default:
 739                 pr_debug("Unknown addr space %d\n",
 740                         (u32) (perf->control_register.space_id));
 741                 result = -ENODEV;
 742                 goto err_unreg;
 743         }
 744
 745         data->freq_table = kzalloc(sizeof(*data->freq_table) *
 746                     (perf->state_count+1), GFP_KERNEL);
 747         if (!data->freq_table) {
 748                 result = -ENOMEM;
 749                 goto err_unreg;
 750         }
 751
 752         /* detect transition latency */
 753         policy->cpuinfo.transition_latency = 0;
 754         for (i = 0; i < perf->state_count; i++) {
 755                 if ((perf->states[i].transition_latency * 1000) >
 756                     policy->cpuinfo.transition_latency)
 757                         policy->cpuinfo.transition_latency =
 758                             perf->states[i].transition_latency * 1000;
 759         }
 760
 761         /* Check for high latency (>20uS) from buggy BIOSes, like on T42 */
 762         if (perf->control_register.space_id == ACPI_ADR_SPACE_FIXED_HARDWARE &&
 763             policy->cpuinfo.transition_latency > 20 * 1000) {
 764                 policy->cpuinfo.transition_latency = 20 * 1000;
 765                 printk_once(KERN_INFO
 766                             "P-state transition latency capped at 20 uS\n");
 767         }
 768
 769         /* table init */
 770         for (i = 0; i < perf->state_count; i++) {
 771                 if (i > 0 && perf->states[i].core_frequency >=
 772                     data->freq_table[valid_states-1].frequency / 1000)
 773                         continue;
 774
 775                 data->freq_table[valid_states].driver_data = i;
 776                 data->freq_table[valid_states].frequency =
 777                     perf->states[i].core_frequency * 1000;
 778                 valid_states++;
 779         }
 780         data->freq_table[valid_states].frequency = CPUFREQ_TABLE_END;
 781         perf->state = 0;
 782
 783         result = cpufreq_table_validate_and_show(policy, data->freq_table);
 784         if (result)
 785                 goto err_freqfree;
 786
 787         if (perf->states[0].core_frequency * 1000 != policy->cpuinfo.max_freq)
 788                 printk(KERN_WARNING FW_WARN "P-state 0 is not max freq\n");
 789
 790         switch (perf->control_register.space_id) {
 791         case ACPI_ADR_SPACE_SYSTEM_IO:
 792                 /*
 793                  * The core will not set policy->cur, because
 794                  * cpufreq_driver->get is NULL, so we need to set it here.
 795                  * However, we have to guess it, because the current speed is
 796                  * unknown and not detectable via IO ports.
 797                  */
 798                 policy->cur = acpi_cpufreq_guess_freq(data, policy->cpu);
 799                 break;
 800         case ACPI_ADR_SPACE_FIXED_HARDWARE:
 801                 acpi_cpufreq_driver.get = get_cur_freq_on_cpu;
 802                 break;
 803         default:
 804                 break;
 805         }
 806
 807         /* notify BIOS that we exist */
 808         acpi_processor_notify_smm(THIS_MODULE);
 809
 810         pr_debug("CPU%u - ACPI performance management activated.\n", cpu);
 811         for (i = 0; i < perf->state_count; i++)
 812                 pr_debug("     %cP%d: %d MHz, %d mW, %d uS\n",
 813                         (i == perf->state ? '*' : ' '), i,
 814                         (u32) perf->states[i].core_frequency,
 815                         (u32) perf->states[i].power,
 816                         (u32) perf->states[i].transition_latency);
 817
 818         /*
 819          * the first call to ->target() should result in us actually
 820          * writing something to the appropriate registers.
 821          */
 822         data->resume = 1;
 823
 824         return result;
 825
 826 err_freqfree:
 827         kfree(data->freq_table);
 828 err_unreg:
 829         acpi_processor_unregister_performance(cpu);
 830 err_free_mask:
 831         free_cpumask_var(data->freqdomain_cpus);
 832 err_free:
 833         kfree(data);
 834         policy->driver_data = NULL;
 835
 836         return result;
 837 }
 838
 839 static int acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy)
 840 {
 841         struct acpi_cpufreq_data *data = policy->driver_data;
 842
 843         pr_debug("acpi_cpufreq_cpu_exit\n");
 844
 845         if (data) {
 846                 policy->driver_data = NULL;
 847                 acpi_processor_unregister_performance(data->acpi_perf_cpu);
 848                 free_cpumask_var(data->freqdomain_cpus);
 849                 kfree(data->freq_table);
 850                 kfree(data);
 851         }
 852
 853         return 0;
 854 }
 855
 856 static int acpi_cpufreq_resume(struct cpufreq_policy *policy)
 857 {
 858         struct acpi_cpufreq_data *data = policy->driver_data;
 859
 860         pr_debug("acpi_cpufreq_resume\n");
 861
 862         data->resume = 1;
 863
 864         return 0;
 865 }
 866
 867 static struct freq_attr *acpi_cpufreq_attr[] = {
 868         &cpufreq_freq_attr_scaling_available_freqs,
 869         &freqdomain_cpus,
 870 #ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
 871         &cpb,
 872 #endif
 873         NULL,
 874 };
 875
 876 static struct cpufreq_driver acpi_cpufreq_driver = {
 877         .verify         = cpufreq_generic_frequency_table_verify,
 878         .target_index   = acpi_cpufreq_target,
 879         .bios_limit     = acpi_processor_get_bios_limit,
 880         .init           = acpi_cpufreq_cpu_init,
 881         .exit           = acpi_cpufreq_cpu_exit,
 882         .resume         = acpi_cpufreq_resume,
 883         .name           = "acpi-cpufreq",
 884         .attr           = acpi_cpufreq_attr,
 885 };
 886
 887 static void __init acpi_cpufreq_boost_init(void)
 888 {
 889         if (boot_cpu_has(X86_FEATURE_CPB) || boot_cpu_has(X86_FEATURE_IDA)) {
 890                 msrs = msrs_alloc();
 891
 892                 if (!msrs)
 893                         return;
 894
 895                 acpi_cpufreq_driver.set_boost = set_boost;
 896                 acpi_cpufreq_driver.boost_enabled = boost_state(0);
 897
 898                 cpu_notifier_register_begin();
 899
 900                 /* Force all MSRs to the same value */
 901                 boost_set_msrs(acpi_cpufreq_driver.boost_enabled,
 902                                cpu_online_mask);
 903
 904                 __register_cpu_notifier(&boost_nb);
 905
 906                 cpu_notifier_register_done();
 907         }
 908 }
 909
 910 static void acpi_cpufreq_boost_exit(void)
 911 {
 912         if (msrs) {
 913                 unregister_cpu_notifier(&boost_nb);
 914
 915                 msrs_free(msrs);
 916                 msrs = NULL;
 917         }
 918 }
 919
 920 static int __init acpi_cpufreq_init(void)
 921 {
 922         int ret;
 923
 924         if (acpi_disabled)
 925                 return -ENODEV;
 926
 927         /* don't keep reloading if cpufreq_driver exists */
 928         if (cpufreq_get_current_driver())
 929                 return -EEXIST;
 930
 931         pr_debug("acpi_cpufreq_init\n");
 932
 933         ret = acpi_cpufreq_early_init();
 934         if (ret)
 935                 return ret;
 936
 937 #ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
 938         /* this is a sysfs file with a strange name and an even stranger
 939          * semantic - per CPU instantiation, but system global effect.
 940          * Lets enable it only on AMD CPUs for compatibility reasons and
 941          * only if configured. This is considered legacy code, which
 942          * will probably be removed at some point in the future.
 943          */
 944         if (!check_amd_hwpstate_cpu(0)) {
 945                 struct freq_attr **attr;
 946
 947                 pr_debug("CPB unsupported, do not expose it\n");
 948
 949                 for (attr = acpi_cpufreq_attr; *attr; attr++)
 950                         if (*attr == &cpb) {
 951                                 *attr = NULL;
 952                                 break;
 953                         }
 954         }
 955 #endif
 956         acpi_cpufreq_boost_init();
 957
 958         ret = cpufreq_register_driver(&acpi_cpufreq_driver);
 959         if (ret) {
 960                 free_acpi_perf_data();
 961                 acpi_cpufreq_boost_exit();
 962         }
 963         return ret;
 964 }
 965
 966 static void __exit acpi_cpufreq_exit(void)
 967 {
 968         pr_debug("acpi_cpufreq_exit\n");
 969
 970         acpi_cpufreq_boost_exit();
 971
 972         cpufreq_unregister_driver(&acpi_cpufreq_driver);
 973
 974         free_acpi_perf_data();
 975 }
 976
 977 module_param(acpi_pstate_strict, uint, 0644);
 978 MODULE_PARM_DESC(acpi_pstate_strict,
 979         "value 0 or non-zero. non-zero -> strict ACPI checks are "
 980         "performed during frequency changes.");
 981
 982 late_initcall(acpi_cpufreq_init);
 983 module_exit(acpi_cpufreq_exit);
 984
 985 static const struct x86_cpu_id acpi_cpufreq_ids[] = {
 986         X86_FEATURE_MATCH(X86_FEATURE_ACPI),
 987         X86_FEATURE_MATCH(X86_FEATURE_HW_PSTATE),
 988         {}
 989 };
 990 MODULE_DEVICE_TABLE(x86cpu, acpi_cpufreq_ids);
 991
 992 static const struct acpi_device_id processor_device_ids[] = {
 993         {ACPI_PROCESSOR_OBJECT_HID, },
 994         {ACPI_PROCESSOR_DEVICE_HID, },
 995         {},
 996 };
 997 MODULE_DEVICE_TABLE(acpi, processor_device_ids);
 998
 999 MODULE_ALIAS("acpi");