arch/x86/kernel/cpu/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 #include <trace/events/power.h>
  38
  39 #include <linux/acpi.h>
  40 #include <linux/io.h>
  41 #include <linux/delay.h>
  42 #include <linux/uaccess.h>
  43
  44 #include <acpi/processor.h>
  45
  46 #include <asm/msr.h>
  47 #include <asm/processor.h>
  48 #include <asm/cpufeature.h>
  49 #include "mperf.h"
  50
  51 #define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_DRIVER, \
  52                 "acpi-cpufreq", msg)
  53
  54 MODULE_AUTHOR("Paul Diefenbaugh, Dominik Brodowski");
  55 MODULE_DESCRIPTION("ACPI Processor P-States Driver");
  56 MODULE_LICENSE("GPL");
  57
  58 enum {
  59         UNDEFINED_CAPABLE = 0,
  60         SYSTEM_INTEL_MSR_CAPABLE,
  61         SYSTEM_IO_CAPABLE,
  62 };
  63
  64 #define INTEL_MSR_RANGE         (0xffff)
  65
  66 struct acpi_cpufreq_data {
  67         struct acpi_processor_performance *acpi_data;
  68         struct cpufreq_frequency_table *freq_table;
  69         unsigned int resume;
  70         unsigned int cpu_feature;
  71 };
  72
  73 static DEFINE_PER_CPU(struct acpi_cpufreq_data *, acfreq_data);
  74
  75 /* acpi_perf_data is a pointer to percpu data. */
  76 static struct acpi_processor_performance *acpi_perf_data;
  77
  78 static struct cpufreq_driver acpi_cpufreq_driver;
  79
  80 static unsigned int acpi_pstate_strict;
  81
  82 static int check_est_cpu(unsigned int cpuid)
  83 {
  84         struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
  85
  86         return cpu_has(cpu, X86_FEATURE_EST);
  87 }
  88
  89 static unsigned extract_io(u32 value, struct acpi_cpufreq_data *data)
  90 {
  91         struct acpi_processor_performance *perf;
  92         int i;
  93
  94         perf = data->acpi_data;
  95
  96         for (i = 0; i < perf->state_count; i++) {
  97                 if (value == perf->states[i].status)
  98                         return data->freq_table[i].frequency;
  99         }
 100         return 0;
 101 }
 102
 103 static unsigned extract_msr(u32 msr, struct acpi_cpufreq_data *data)
 104 {
 105         int i;
 106         struct acpi_processor_performance *perf;
 107
 108         msr &= INTEL_MSR_RANGE;
 109         perf = data->acpi_data;
 110
 111         for (i = 0; data->freq_table[i].frequency != CPUFREQ_TABLE_END; i++) {
 112                 if (msr == perf->states[data->freq_table[i].index].status)
 113                         return data->freq_table[i].frequency;
 114         }
 115         return data->freq_table[0].frequency;
 116 }
 117
 118 static unsigned extract_freq(u32 val, struct acpi_cpufreq_data *data)
 119 {
 120         switch (data->cpu_feature) {
 121         case SYSTEM_INTEL_MSR_CAPABLE:
 122                 return extract_msr(val, data);
 123         case SYSTEM_IO_CAPABLE:
 124                 return extract_io(val, data);
 125         default:
 126                 return 0;
 127         }
 128 }
 129
 130 struct msr_addr {
 131         u32 reg;
 132 };
 133
 134 struct io_addr {
 135         u16 port;
 136         u8 bit_width;
 137 };
 138
 139 struct drv_cmd {
 140         unsigned int type;
 141         const struct cpumask *mask;
 142         union {
 143                 struct msr_addr msr;
 144                 struct io_addr io;
 145         } addr;
 146         u32 val;
 147 };
 148
 149 /* Called via smp_call_function_single(), on the target CPU */
 150 static void do_drv_read(void *_cmd)
 151 {
 152         struct drv_cmd *cmd = _cmd;
 153         u32 h;
 154
 155         switch (cmd->type) {
 156         case SYSTEM_INTEL_MSR_CAPABLE:
 157                 rdmsr(cmd->addr.msr.reg, cmd->val, h);
 158                 break;
 159         case SYSTEM_IO_CAPABLE:
 160                 acpi_os_read_port((acpi_io_address)cmd->addr.io.port,
 161                                 &cmd->val,
 162                                 (u32)cmd->addr.io.bit_width);
 163                 break;
 164         default:
 165                 break;
 166         }
 167 }
 168
 169 /* Called via smp_call_function_many(), on the target CPUs */
 170 static void do_drv_write(void *_cmd)
 171 {
 172         struct drv_cmd *cmd = _cmd;
 173         u32 lo, hi;
 174
 175         switch (cmd->type) {
 176         case SYSTEM_INTEL_MSR_CAPABLE:
 177                 rdmsr(cmd->addr.msr.reg, lo, hi);
 178                 lo = (lo & ~INTEL_MSR_RANGE) | (cmd->val & INTEL_MSR_RANGE);
 179                 wrmsr(cmd->addr.msr.reg, lo, hi);
 180                 break;
 181         case SYSTEM_IO_CAPABLE:
 182                 acpi_os_write_port((acpi_io_address)cmd->addr.io.port,
 183                                 cmd->val,
 184                                 (u32)cmd->addr.io.bit_width);
 185                 break;
 186         default:
 187                 break;
 188         }
 189 }
 190
 191 static void drv_read(struct drv_cmd *cmd)
 192 {
 193         int err;
 194         cmd->val = 0;
 195
 196         err = smp_call_function_any(cmd->mask, do_drv_read, cmd, 1);
 197         WARN_ON_ONCE(err);      /* smp_call_function_any() was buggy? */
 198 }
 199
 200 static void drv_write(struct drv_cmd *cmd)
 201 {
 202         int this_cpu;
 203
 204         this_cpu = get_cpu();
 205         if (cpumask_test_cpu(this_cpu, cmd->mask))
 206                 do_drv_write(cmd);
 207         smp_call_function_many(cmd->mask, do_drv_write, cmd, 1);
 208         put_cpu();
 209 }
 210
 211 static u32 get_cur_val(const struct cpumask *mask)
 212 {
 213         struct acpi_processor_performance *perf;
 214         struct drv_cmd cmd;
 215
 216         if (unlikely(cpumask_empty(mask)))
 217                 return 0;
 218
 219         switch (per_cpu(acfreq_data, cpumask_first(mask))->cpu_feature) {
 220         case SYSTEM_INTEL_MSR_CAPABLE:
 221                 cmd.type = SYSTEM_INTEL_MSR_CAPABLE;
 222                 cmd.addr.msr.reg = MSR_IA32_PERF_STATUS;
 223                 break;
 224         case SYSTEM_IO_CAPABLE:
 225                 cmd.type = SYSTEM_IO_CAPABLE;
 226                 perf = per_cpu(acfreq_data, cpumask_first(mask))->acpi_data;
 227                 cmd.addr.io.port = perf->control_register.address;
 228                 cmd.addr.io.bit_width = perf->control_register.bit_width;
 229                 break;
 230         default:
 231                 return 0;
 232         }
 233
 234         cmd.mask = mask;
 235         drv_read(&cmd);
 236
 237         dprintk("get_cur_val = %u\n", cmd.val);
 238
 239         return cmd.val;
 240 }
 241
 242 static unsigned int get_cur_freq_on_cpu(unsigned int cpu)
 243 {
 244         struct acpi_cpufreq_data *data = per_cpu(acfreq_data, cpu);
 245         unsigned int freq;
 246         unsigned int cached_freq;
 247
 248         dprintk("get_cur_freq_on_cpu (%d)\n", cpu);
 249
 250         if (unlikely(data == NULL ||
 251                      data->acpi_data == NULL || data->freq_table == NULL)) {
 252                 return 0;
 253         }
 254
 255         cached_freq = data->freq_table[data->acpi_data->state].frequency;
 256         freq = extract_freq(get_cur_val(cpumask_of(cpu)), data);
 257         if (freq != cached_freq) {
 258                 /*
 259                  * The dreaded BIOS frequency change behind our back.
 260                  * Force set the frequency on next target call.
 261                  */
 262                 data->resume = 1;
 263         }
 264
 265         dprintk("cur freq = %u\n", freq);
 266
 267         return freq;
 268 }
 269
 270 static unsigned int check_freqs(const struct cpumask *mask, unsigned int freq,
 271                                 struct acpi_cpufreq_data *data)
 272 {
 273         unsigned int cur_freq;
 274         unsigned int i;
 275
 276         for (i = 0; i < 100; i++) {
 277                 cur_freq = extract_freq(get_cur_val(mask), data);
 278                 if (cur_freq == freq)
 279                         return 1;
 280                 udelay(10);
 281         }
 282         return 0;
 283 }
 284
 285 static int acpi_cpufreq_target(struct cpufreq_policy *policy,
 286                                unsigned int target_freq, unsigned int relation)
 287 {
 288         struct acpi_cpufreq_data *data = per_cpu(acfreq_data, policy->cpu);
 289         struct acpi_processor_performance *perf;
 290         struct cpufreq_freqs freqs;
 291         struct drv_cmd cmd;
 292         unsigned int next_state = 0; /* Index into freq_table */
 293         unsigned int next_perf_state = 0; /* Index into perf table */
 294         unsigned int i;
 295         int result = 0;
 296
 297         dprintk("acpi_cpufreq_target %d (%d)\n", target_freq, policy->cpu);
 298
 299         if (unlikely(data == NULL ||
 300              data->acpi_data == NULL || data->freq_table == NULL)) {
 301                 return -ENODEV;
 302         }
 303
 304         perf = data->acpi_data;
 305         result = cpufreq_frequency_table_target(policy,
 306                                                 data->freq_table,
 307                                                 target_freq,
 308                                                 relation, &next_state);
 309         if (unlikely(result)) {
 310                 result = -ENODEV;
 311                 goto out;
 312         }
 313
 314         next_perf_state = data->freq_table[next_state].index;
 315         if (perf->state == next_perf_state) {
 316                 if (unlikely(data->resume)) {
 317                         dprintk("Called after resume, resetting to P%d\n",
 318                                 next_perf_state);
 319                         data->resume = 0;
 320                 } else {
 321                         dprintk("Already at target state (P%d)\n",
 322                                 next_perf_state);
 323                         goto out;
 324                 }
 325         }
 326
 327         trace_power_frequency(POWER_PSTATE, data->freq_table[next_state].frequency);
 328
 329         switch (data->cpu_feature) {
 330         case SYSTEM_INTEL_MSR_CAPABLE:
 331                 cmd.type = SYSTEM_INTEL_MSR_CAPABLE;
 332                 cmd.addr.msr.reg = MSR_IA32_PERF_CTL;
 333                 cmd.val = (u32) perf->states[next_perf_state].control;
 334                 break;
 335         case SYSTEM_IO_CAPABLE:
 336                 cmd.type = SYSTEM_IO_CAPABLE;
 337                 cmd.addr.io.port = perf->control_register.address;
 338                 cmd.addr.io.bit_width = perf->control_register.bit_width;
 339                 cmd.val = (u32) perf->states[next_perf_state].control;
 340                 break;
 341         default:
 342                 result = -ENODEV;
 343                 goto out;
 344         }
 345
 346         /* cpufreq holds the hotplug lock, so we are safe from here on */
 347         if (policy->shared_type != CPUFREQ_SHARED_TYPE_ANY)
 348                 cmd.mask = policy->cpus;
 349         else
 350                 cmd.mask = cpumask_of(policy->cpu);
 351
 352         freqs.old = perf->states[perf->state].core_frequency * 1000;
 353         freqs.new = data->freq_table[next_state].frequency;
 354         for_each_cpu(i, cmd.mask) {
 355                 freqs.cpu = i;
 356                 cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
 357         }
 358
 359         drv_write(&cmd);
 360
 361         if (acpi_pstate_strict) {
 362                 if (!check_freqs(cmd.mask, freqs.new, data)) {
 363                         dprintk("acpi_cpufreq_target failed (%d)\n",
 364                                 policy->cpu);
 365                         result = -EAGAIN;
 366                         goto out;
 367                 }
 368         }
 369
 370         for_each_cpu(i, cmd.mask) {
 371                 freqs.cpu = i;
 372                 cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
 373         }
 374         perf->state = next_perf_state;
 375
 376 out:
 377         return result;
 378 }
 379
 380 static int acpi_cpufreq_verify(struct cpufreq_policy *policy)
 381 {
 382         struct acpi_cpufreq_data *data = per_cpu(acfreq_data, policy->cpu);
 383
 384         dprintk("acpi_cpufreq_verify\n");
 385
 386         return cpufreq_frequency_table_verify(policy, data->freq_table);
 387 }
 388
 389 static unsigned long
 390 acpi_cpufreq_guess_freq(struct acpi_cpufreq_data *data, unsigned int cpu)
 391 {
 392         struct acpi_processor_performance *perf = data->acpi_data;
 393
 394         if (cpu_khz) {
 395                 /* search the closest match to cpu_khz */
 396                 unsigned int i;
 397                 unsigned long freq;
 398                 unsigned long freqn = perf->states[0].core_frequency * 1000;
 399
 400                 for (i = 0; i < (perf->state_count-1); i++) {
 401                         freq = freqn;
 402                         freqn = perf->states[i+1].core_frequency * 1000;
 403                         if ((2 * cpu_khz) > (freqn + freq)) {
 404                                 perf->state = i;
 405                                 return freq;
 406                         }
 407                 }
 408                 perf->state = perf->state_count-1;
 409                 return freqn;
 410         } else {
 411                 /* assume CPU is at P0... */
 412                 perf->state = 0;
 413                 return perf->states[0].core_frequency * 1000;
 414         }
 415 }
 416
 417 static void free_acpi_perf_data(void)
 418 {
 419         unsigned int i;
 420
 421         /* Freeing a NULL pointer is OK, and alloc_percpu zeroes. */
 422         for_each_possible_cpu(i)
 423                 free_cpumask_var(per_cpu_ptr(acpi_perf_data, i)
 424                                  ->shared_cpu_map);
 425         free_percpu(acpi_perf_data);
 426 }
 427
 428 /*
 429  * acpi_cpufreq_early_init - initialize ACPI P-States library
 430  *
 431  * Initialize the ACPI P-States library (drivers/acpi/processor_perflib.c)
 432  * in order to determine correct frequency and voltage pairings. We can
 433  * do _PDC and _PSD and find out the processor dependency for the
 434  * actual init that will happen later...
 435  */
 436 static int __init acpi_cpufreq_early_init(void)
 437 {
 438         unsigned int i;
 439         dprintk("acpi_cpufreq_early_init\n");
 440
 441         acpi_perf_data = alloc_percpu(struct acpi_processor_performance);
 442         if (!acpi_perf_data) {
 443                 dprintk("Memory allocation error for acpi_perf_data.\n");
 444                 return -ENOMEM;
 445         }
 446         for_each_possible_cpu(i) {
 447                 if (!zalloc_cpumask_var_node(
 448                         &per_cpu_ptr(acpi_perf_data, i)->shared_cpu_map,
 449                         GFP_KERNEL, cpu_to_node(i))) {
 450
 451                         /* Freeing a NULL pointer is OK: alloc_percpu zeroes. */
 452                         free_acpi_perf_data();
 453                         return -ENOMEM;
 454                 }
 455         }
 456
 457         /* Do initialization in ACPI core */
 458         acpi_processor_preregister_performance(acpi_perf_data);
 459         return 0;
 460 }
 461
 462 #ifdef CONFIG_SMP
 463 /*
 464  * Some BIOSes do SW_ANY coordination internally, either set it up in hw
 465  * or do it in BIOS firmware and won't inform about it to OS. If not
 466  * detected, this has a side effect of making CPU run at a different speed
 467  * than OS intended it to run at. Detect it and handle it cleanly.
 468  */
 469 static int bios_with_sw_any_bug;
 470
 471 static int sw_any_bug_found(const struct dmi_system_id *d)
 472 {
 473         bios_with_sw_any_bug = 1;
 474         return 0;
 475 }
 476
 477 static const struct dmi_system_id sw_any_bug_dmi_table[] = {
 478         {
 479                 .callback = sw_any_bug_found,
 480                 .ident = "Supermicro Server X6DLP",
 481                 .matches = {
 482                         DMI_MATCH(DMI_SYS_VENDOR, "Supermicro"),
 483                         DMI_MATCH(DMI_BIOS_VERSION, "080010"),
 484                         DMI_MATCH(DMI_PRODUCT_NAME, "X6DLP"),
 485                 },
 486         },
 487         { }
 488 };
 489
 490 static int acpi_cpufreq_blacklist(struct cpuinfo_x86 *c)
 491 {
 492         /* Intel Xeon Processor 7100 Series Specification Update
 493          * http://www.intel.com/Assets/PDF/specupdate/314554.pdf
 494          * AL30: A Machine Check Exception (MCE) Occurring during an
 495          * Enhanced Intel SpeedStep Technology Ratio Change May Cause
 496          * Both Processor Cores to Lock Up. */
 497         if (c->x86_vendor == X86_VENDOR_INTEL) {
 498                 if ((c->x86 == 15) &&
 499                     (c->x86_model == 6) &&
 500                     (c->x86_mask == 8)) {
 501                         printk(KERN_INFO "acpi-cpufreq: Intel(R) "
 502                             "Xeon(R) 7100 Errata AL30, processors may "
 503                             "lock up on frequency changes: disabling "
 504                             "acpi-cpufreq.\n");
 505                         return -ENODEV;
 506                     }
 507                 }
 508         return 0;
 509 }
 510 #endif
 511
 512 static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
 513 {
 514         unsigned int i;
 515         unsigned int valid_states = 0;
 516         unsigned int cpu = policy->cpu;
 517         struct acpi_cpufreq_data *data;
 518         unsigned int result = 0;
 519         struct cpuinfo_x86 *c = &cpu_data(policy->cpu);
 520         struct acpi_processor_performance *perf;
 521 #ifdef CONFIG_SMP
 522         static int blacklisted;
 523 #endif
 524
 525         dprintk("acpi_cpufreq_cpu_init\n");
 526
 527 #ifdef CONFIG_SMP
 528         if (blacklisted)
 529                 return blacklisted;
 530         blacklisted = acpi_cpufreq_blacklist(c);
 531         if (blacklisted)
 532                 return blacklisted;
 533 #endif
 534
 535         data = kzalloc(sizeof(struct acpi_cpufreq_data), GFP_KERNEL);
 536         if (!data)
 537                 return -ENOMEM;
 538
 539         data->acpi_data = per_cpu_ptr(acpi_perf_data, cpu);
 540         per_cpu(acfreq_data, cpu) = data;
 541
 542         if (cpu_has(c, X86_FEATURE_CONSTANT_TSC))
 543                 acpi_cpufreq_driver.flags |= CPUFREQ_CONST_LOOPS;
 544
 545         result = acpi_processor_register_performance(data->acpi_data, cpu);
 546         if (result)
 547                 goto err_free;
 548
 549         perf = data->acpi_data;
 550         policy->shared_type = perf->shared_type;
 551
 552         /*
 553          * Will let policy->cpus know about dependency only when software
 554          * coordination is required.
 555          */
 556         if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL ||
 557             policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {
 558                 cpumask_copy(policy->cpus, perf->shared_cpu_map);
 559         }
 560         cpumask_copy(policy->related_cpus, perf->shared_cpu_map);
 561
 562 #ifdef CONFIG_SMP
 563         dmi_check_system(sw_any_bug_dmi_table);
 564         if (bios_with_sw_any_bug && cpumask_weight(policy->cpus) == 1) {
 565                 policy->shared_type = CPUFREQ_SHARED_TYPE_ALL;
 566                 cpumask_copy(policy->cpus, cpu_core_mask(cpu));
 567         }
 568 #endif
 569
 570         /* capability check */
 571         if (perf->state_count <= 1) {
 572                 dprintk("No P-States\n");
 573                 result = -ENODEV;
 574                 goto err_unreg;
 575         }
 576
 577         if (perf->control_register.space_id != perf->status_register.space_id) {
 578                 result = -ENODEV;
 579                 goto err_unreg;
 580         }
 581
 582         switch (perf->control_register.space_id) {
 583         case ACPI_ADR_SPACE_SYSTEM_IO:
 584                 dprintk("SYSTEM IO addr space\n");
 585                 data->cpu_feature = SYSTEM_IO_CAPABLE;
 586                 break;
 587         case ACPI_ADR_SPACE_FIXED_HARDWARE:
 588                 dprintk("HARDWARE addr space\n");
 589                 if (!check_est_cpu(cpu)) {
 590                         result = -ENODEV;
 591                         goto err_unreg;
 592                 }
 593                 data->cpu_feature = SYSTEM_INTEL_MSR_CAPABLE;
 594                 break;
 595         default:
 596                 dprintk("Unknown addr space %d\n",
 597                         (u32) (perf->control_register.space_id));
 598                 result = -ENODEV;
 599                 goto err_unreg;
 600         }
 601
 602         data->freq_table = kmalloc(sizeof(struct cpufreq_frequency_table) *
 603                     (perf->state_count+1), GFP_KERNEL);
 604         if (!data->freq_table) {
 605                 result = -ENOMEM;
 606                 goto err_unreg;
 607         }
 608
 609         /* detect transition latency */
 610         policy->cpuinfo.transition_latency = 0;
 611         for (i = 0; i < perf->state_count; i++) {
 612                 if ((perf->states[i].transition_latency * 1000) >
 613                     policy->cpuinfo.transition_latency)
 614                         policy->cpuinfo.transition_latency =
 615                             perf->states[i].transition_latency * 1000;
 616         }
 617
 618         /* Check for high latency (>20uS) from buggy BIOSes, like on T42 */
 619         if (perf->control_register.space_id == ACPI_ADR_SPACE_FIXED_HARDWARE &&
 620             policy->cpuinfo.transition_latency > 20 * 1000) {
 621                 policy->cpuinfo.transition_latency = 20 * 1000;
 622                 printk_once(KERN_INFO
 623                             "P-state transition latency capped at 20 uS\n");
 624         }
 625
 626         /* table init */
 627         for (i = 0; i < perf->state_count; i++) {
 628                 if (i > 0 && perf->states[i].core_frequency >=
 629                     data->freq_table[valid_states-1].frequency / 1000)
 630                         continue;
 631
 632                 data->freq_table[valid_states].index = i;
 633                 data->freq_table[valid_states].frequency =
 634                     perf->states[i].core_frequency * 1000;
 635                 valid_states++;
 636         }
 637         data->freq_table[valid_states].frequency = CPUFREQ_TABLE_END;
 638         perf->state = 0;
 639
 640         result = cpufreq_frequency_table_cpuinfo(policy, data->freq_table);
 641         if (result)
 642                 goto err_freqfree;
 643
 644         if (perf->states[0].core_frequency * 1000 != policy->cpuinfo.max_freq)
 645                 printk(KERN_WARNING FW_WARN "P-state 0 is not max freq\n");
 646
 647         switch (perf->control_register.space_id) {
 648         case ACPI_ADR_SPACE_SYSTEM_IO:
 649                 /* Current speed is unknown and not detectable by IO port */
 650                 policy->cur = acpi_cpufreq_guess_freq(data, policy->cpu);
 651                 break;
 652         case ACPI_ADR_SPACE_FIXED_HARDWARE:
 653                 acpi_cpufreq_driver.get = get_cur_freq_on_cpu;
 654                 policy->cur = get_cur_freq_on_cpu(cpu);
 655                 break;
 656         default:
 657                 break;
 658         }
 659
 660         /* notify BIOS that we exist */
 661         acpi_processor_notify_smm(THIS_MODULE);
 662
 663         /* Check for APERF/MPERF support in hardware */
 664         if (cpu_has(c, X86_FEATURE_APERFMPERF))
 665                 acpi_cpufreq_driver.getavg = cpufreq_get_measured_perf;
 666
 667         dprintk("CPU%u - ACPI performance management activated.\n", cpu);
 668         for (i = 0; i < perf->state_count; i++)
 669                 dprintk("     %cP%d: %d MHz, %d mW, %d uS\n",
 670                         (i == perf->state ? '*' : ' '), i,
 671                         (u32) perf->states[i].core_frequency,
 672                         (u32) perf->states[i].power,
 673                         (u32) perf->states[i].transition_latency);
 674
 675         cpufreq_frequency_table_get_attr(data->freq_table, policy->cpu);
 676
 677         /*
 678          * the first call to ->target() should result in us actually
 679          * writing something to the appropriate registers.
 680          */
 681         data->resume = 1;
 682
 683         return result;
 684
 685 err_freqfree:
 686         kfree(data->freq_table);
 687 err_unreg:
 688         acpi_processor_unregister_performance(perf, cpu);
 689 err_free:
 690         kfree(data);
 691         per_cpu(acfreq_data, cpu) = NULL;
 692
 693         return result;
 694 }
 695
 696 static int acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy)
 697 {
 698         struct acpi_cpufreq_data *data = per_cpu(acfreq_data, policy->cpu);
 699
 700         dprintk("acpi_cpufreq_cpu_exit\n");
 701
 702         if (data) {
 703                 cpufreq_frequency_table_put_attr(policy->cpu);
 704                 per_cpu(acfreq_data, policy->cpu) = NULL;
 705                 acpi_processor_unregister_performance(data->acpi_data,
 706                                                       policy->cpu);
 707                 kfree(data);
 708         }
 709
 710         return 0;
 711 }
 712
 713 static int acpi_cpufreq_resume(struct cpufreq_policy *policy)
 714 {
 715         struct acpi_cpufreq_data *data = per_cpu(acfreq_data, policy->cpu);
 716
 717         dprintk("acpi_cpufreq_resume\n");
 718
 719         data->resume = 1;
 720
 721         return 0;
 722 }
 723
 724 static struct freq_attr *acpi_cpufreq_attr[] = {
 725         &cpufreq_freq_attr_scaling_available_freqs,
 726         NULL,
 727 };
 728
 729 static struct cpufreq_driver acpi_cpufreq_driver = {
 730         .verify         = acpi_cpufreq_verify,
 731         .target         = acpi_cpufreq_target,
 732         .bios_limit     = acpi_processor_get_bios_limit,
 733         .init           = acpi_cpufreq_cpu_init,
 734         .exit           = acpi_cpufreq_cpu_exit,
 735         .resume         = acpi_cpufreq_resume,
 736         .name           = "acpi-cpufreq",
 737         .owner          = THIS_MODULE,
 738         .attr           = acpi_cpufreq_attr,
 739 };
 740
 741 static int __init acpi_cpufreq_init(void)
 742 {
 743         int ret;
 744
 745         if (acpi_disabled)
 746                 return 0;
 747
 748         dprintk("acpi_cpufreq_init\n");
 749
 750         ret = acpi_cpufreq_early_init();
 751         if (ret)
 752                 return ret;
 753
 754         ret = cpufreq_register_driver(&acpi_cpufreq_driver);
 755         if (ret)
 756                 free_acpi_perf_data();
 757
 758         return ret;
 759 }
 760
 761 static void __exit acpi_cpufreq_exit(void)
 762 {
 763         dprintk("acpi_cpufreq_exit\n");
 764
 765         cpufreq_unregister_driver(&acpi_cpufreq_driver);
 766
 767         free_percpu(acpi_perf_data);
 768 }
 769
 770 module_param(acpi_pstate_strict, uint, 0644);
 771 MODULE_PARM_DESC(acpi_pstate_strict,
 772         "value 0 or non-zero. non-zero -> strict ACPI checks are "
 773         "performed during frequency changes.");
 774
 775 late_initcall(acpi_cpufreq_init);
 776 module_exit(acpi_cpufreq_exit);
 777
 778 MODULE_ALIAS("acpi");