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 <trace/power.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 #define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_DRIVER, \
  50                 "acpi-cpufreq", msg)
  51
  52 MODULE_AUTHOR("Paul Diefenbaugh, Dominik Brodowski");
  53 MODULE_DESCRIPTION("ACPI Processor P-States Driver");
  54 MODULE_LICENSE("GPL");
  55
  56 enum {
  57         UNDEFINED_CAPABLE = 0,
  58         SYSTEM_INTEL_MSR_CAPABLE,
  59         SYSTEM_IO_CAPABLE,
  60 };
  61
  62 #define INTEL_MSR_RANGE         (0xffff)
  63
  64 struct acpi_cpufreq_data {
  65         struct acpi_processor_performance *acpi_data;
  66         struct cpufreq_frequency_table *freq_table;
  67         unsigned int resume;
  68         unsigned int cpu_feature;
  69 };
  70
  71 static DEFINE_PER_CPU(struct acpi_cpufreq_data *, drv_data);
  72
  73 static DEFINE_PER_CPU(struct aperfmperf, old_perf);
  74
  75 DEFINE_TRACE(power_mark);
  76
  77 /* acpi_perf_data is a pointer to percpu data. */
  78 static struct acpi_processor_performance *acpi_perf_data;
  79
  80 static struct cpufreq_driver acpi_cpufreq_driver;
  81
  82 static unsigned int acpi_pstate_strict;
  83
  84 static int check_est_cpu(unsigned int cpuid)
  85 {
  86         struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
  87
  88         return cpu_has(cpu, X86_FEATURE_EST);
  89 }
  90
  91 static unsigned extract_io(u32 value, struct acpi_cpufreq_data *data)
  92 {
  93         struct acpi_processor_performance *perf;
  94         int i;
  95
  96         perf = data->acpi_data;
  97
  98         for (i = 0; i < perf->state_count; i++) {
  99                 if (value == perf->states[i].status)
 100                         return data->freq_table[i].frequency;
 101         }
 102         return 0;
 103 }
 104
 105 static unsigned extract_msr(u32 msr, struct acpi_cpufreq_data *data)
 106 {
 107         int i;
 108         struct acpi_processor_performance *perf;
 109
 110         msr &= INTEL_MSR_RANGE;
 111         perf = data->acpi_data;
 112
 113         for (i = 0; data->freq_table[i].frequency != CPUFREQ_TABLE_END; i++) {
 114                 if (msr == perf->states[data->freq_table[i].index].status)
 115                         return data->freq_table[i].frequency;
 116         }
 117         return data->freq_table[0].frequency;
 118 }
 119
 120 static unsigned extract_freq(u32 val, struct acpi_cpufreq_data *data)
 121 {
 122         switch (data->cpu_feature) {
 123         case SYSTEM_INTEL_MSR_CAPABLE:
 124                 return extract_msr(val, data);
 125         case SYSTEM_IO_CAPABLE:
 126                 return extract_io(val, data);
 127         default:
 128                 return 0;
 129         }
 130 }
 131
 132 struct msr_addr {
 133         u32 reg;
 134 };
 135
 136 struct io_addr {
 137         u16 port;
 138         u8 bit_width;
 139 };
 140
 141 struct drv_cmd {
 142         unsigned int type;
 143         const struct cpumask *mask;
 144         union {
 145                 struct msr_addr msr;
 146                 struct io_addr io;
 147         } addr;
 148         u32 val;
 149 };
 150
 151 /* Called via smp_call_function_single(), on the target CPU */
 152 static void do_drv_read(void *_cmd)
 153 {
 154         struct drv_cmd *cmd = _cmd;
 155         u32 h;
 156
 157         switch (cmd->type) {
 158         case SYSTEM_INTEL_MSR_CAPABLE:
 159                 rdmsr(cmd->addr.msr.reg, cmd->val, h);
 160                 break;
 161         case SYSTEM_IO_CAPABLE:
 162                 acpi_os_read_port((acpi_io_address)cmd->addr.io.port,
 163                                 &cmd->val,
 164                                 (u32)cmd->addr.io.bit_width);
 165                 break;
 166         default:
 167                 break;
 168         }
 169 }
 170
 171 /* Called via smp_call_function_many(), on the target CPUs */
 172 static void do_drv_write(void *_cmd)
 173 {
 174         struct drv_cmd *cmd = _cmd;
 175         u32 lo, hi;
 176
 177         switch (cmd->type) {
 178         case SYSTEM_INTEL_MSR_CAPABLE:
 179                 rdmsr(cmd->addr.msr.reg, lo, hi);
 180                 lo = (lo & ~INTEL_MSR_RANGE) | (cmd->val & INTEL_MSR_RANGE);
 181                 wrmsr(cmd->addr.msr.reg, lo, hi);
 182                 break;
 183         case SYSTEM_IO_CAPABLE:
 184                 acpi_os_write_port((acpi_io_address)cmd->addr.io.port,
 185                                 cmd->val,
 186                                 (u32)cmd->addr.io.bit_width);
 187                 break;
 188         default:
 189                 break;
 190         }
 191 }
 192
 193 static void drv_read(struct drv_cmd *cmd)
 194 {
 195         cmd->val = 0;
 196
 197         smp_call_function_single(cpumask_any(cmd->mask), do_drv_read, cmd, 1);
 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(drv_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(drv_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 /* Called via smp_call_function_single(), on the target CPU */
 243 static void read_measured_perf_ctrs(void *_cur)
 244 {
 245         struct aperfmperf *am = _cur;
 246
 247         get_aperfmperf(am);
 248 }
 249
 250 /*
 251  * Return the measured active (C0) frequency on this CPU since last call
 252  * to this function.
 253  * Input: cpu number
 254  * Return: Average CPU frequency in terms of max frequency (zero on error)
 255  *
 256  * We use IA32_MPERF and IA32_APERF MSRs to get the measured performance
 257  * over a period of time, while CPU is in C0 state.
 258  * IA32_MPERF counts at the rate of max advertised frequency
 259  * IA32_APERF counts at the rate of actual CPU frequency
 260  * Only IA32_APERF/IA32_MPERF ratio is architecturally defined and
 261  * no meaning should be associated with absolute values of these MSRs.
 262  */
 263 static unsigned int get_measured_perf(struct cpufreq_policy *policy,
 264                                       unsigned int cpu)
 265 {
 266         struct aperfmperf perf;
 267         unsigned long ratio;
 268         unsigned int retval;
 269
 270         if (smp_call_function_single(cpu, read_measured_perf_ctrs, &perf, 1))
 271                 return 0;
 272
 273         ratio = calc_aperfmperf_ratio(&per_cpu(old_perf, cpu), &perf);
 274         per_cpu(old_perf, cpu) = perf;
 275
 276         retval = (policy->cpuinfo.max_freq * ratio) >> APERFMPERF_SHIFT;
 277
 278         return retval;
 279 }
 280
 281 static unsigned int get_cur_freq_on_cpu(unsigned int cpu)
 282 {
 283         struct acpi_cpufreq_data *data = per_cpu(drv_data, cpu);
 284         unsigned int freq;
 285         unsigned int cached_freq;
 286
 287         dprintk("get_cur_freq_on_cpu (%d)\n", cpu);
 288
 289         if (unlikely(data == NULL ||
 290                      data->acpi_data == NULL || data->freq_table == NULL)) {
 291                 return 0;
 292         }
 293
 294         cached_freq = data->freq_table[data->acpi_data->state].frequency;
 295         freq = extract_freq(get_cur_val(cpumask_of(cpu)), data);
 296         if (freq != cached_freq) {
 297                 /*
 298                  * The dreaded BIOS frequency change behind our back.
 299                  * Force set the frequency on next target call.
 300                  */
 301                 data->resume = 1;
 302         }
 303
 304         dprintk("cur freq = %u\n", freq);
 305
 306         return freq;
 307 }
 308
 309 static unsigned int check_freqs(const struct cpumask *mask, unsigned int freq,
 310                                 struct acpi_cpufreq_data *data)
 311 {
 312         unsigned int cur_freq;
 313         unsigned int i;
 314
 315         for (i = 0; i < 100; i++) {
 316                 cur_freq = extract_freq(get_cur_val(mask), data);
 317                 if (cur_freq == freq)
 318                         return 1;
 319                 udelay(10);
 320         }
 321         return 0;
 322 }
 323
 324 static int acpi_cpufreq_target(struct cpufreq_policy *policy,
 325                                unsigned int target_freq, unsigned int relation)
 326 {
 327         struct acpi_cpufreq_data *data = per_cpu(drv_data, policy->cpu);
 328         struct acpi_processor_performance *perf;
 329         struct cpufreq_freqs freqs;
 330         struct drv_cmd cmd;
 331         unsigned int next_state = 0; /* Index into freq_table */
 332         unsigned int next_perf_state = 0; /* Index into perf table */
 333         unsigned int i;
 334         int result = 0;
 335         struct power_trace it;
 336
 337         dprintk("acpi_cpufreq_target %d (%d)\n", target_freq, policy->cpu);
 338
 339         if (unlikely(data == NULL ||
 340              data->acpi_data == NULL || data->freq_table == NULL)) {
 341                 return -ENODEV;
 342         }
 343
 344         perf = data->acpi_data;
 345         result = cpufreq_frequency_table_target(policy,
 346                                                 data->freq_table,
 347                                                 target_freq,
 348                                                 relation, &next_state);
 349         if (unlikely(result)) {
 350                 result = -ENODEV;
 351                 goto out;
 352         }
 353
 354         next_perf_state = data->freq_table[next_state].index;
 355         if (perf->state == next_perf_state) {
 356                 if (unlikely(data->resume)) {
 357                         dprintk("Called after resume, resetting to P%d\n",
 358                                 next_perf_state);
 359                         data->resume = 0;
 360                 } else {
 361                         dprintk("Already at target state (P%d)\n",
 362                                 next_perf_state);
 363                         goto out;
 364                 }
 365         }
 366
 367         trace_power_mark(&it, POWER_PSTATE, next_perf_state);
 368
 369         switch (data->cpu_feature) {
 370         case SYSTEM_INTEL_MSR_CAPABLE:
 371                 cmd.type = SYSTEM_INTEL_MSR_CAPABLE;
 372                 cmd.addr.msr.reg = MSR_IA32_PERF_CTL;
 373                 cmd.val = (u32) perf->states[next_perf_state].control;
 374                 break;
 375         case SYSTEM_IO_CAPABLE:
 376                 cmd.type = SYSTEM_IO_CAPABLE;
 377                 cmd.addr.io.port = perf->control_register.address;
 378                 cmd.addr.io.bit_width = perf->control_register.bit_width;
 379                 cmd.val = (u32) perf->states[next_perf_state].control;
 380                 break;
 381         default:
 382                 result = -ENODEV;
 383                 goto out;
 384         }
 385
 386         /* cpufreq holds the hotplug lock, so we are safe from here on */
 387         if (policy->shared_type != CPUFREQ_SHARED_TYPE_ANY)
 388                 cmd.mask = policy->cpus;
 389         else
 390                 cmd.mask = cpumask_of(policy->cpu);
 391
 392         freqs.old = perf->states[perf->state].core_frequency * 1000;
 393         freqs.new = data->freq_table[next_state].frequency;
 394         for_each_cpu(i, cmd.mask) {
 395                 freqs.cpu = i;
 396                 cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
 397         }
 398
 399         drv_write(&cmd);
 400
 401         if (acpi_pstate_strict) {
 402                 if (!check_freqs(cmd.mask, freqs.new, data)) {
 403                         dprintk("acpi_cpufreq_target failed (%d)\n",
 404                                 policy->cpu);
 405                         result = -EAGAIN;
 406                         goto out;
 407                 }
 408         }
 409
 410         for_each_cpu(i, cmd.mask) {
 411                 freqs.cpu = i;
 412                 cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
 413         }
 414         perf->state = next_perf_state;
 415
 416 out:
 417         return result;
 418 }
 419
 420 static int acpi_cpufreq_verify(struct cpufreq_policy *policy)
 421 {
 422         struct acpi_cpufreq_data *data = per_cpu(drv_data, policy->cpu);
 423
 424         dprintk("acpi_cpufreq_verify\n");
 425
 426         return cpufreq_frequency_table_verify(policy, data->freq_table);
 427 }
 428
 429 static unsigned long
 430 acpi_cpufreq_guess_freq(struct acpi_cpufreq_data *data, unsigned int cpu)
 431 {
 432         struct acpi_processor_performance *perf = data->acpi_data;
 433
 434         if (cpu_khz) {
 435                 /* search the closest match to cpu_khz */
 436                 unsigned int i;
 437                 unsigned long freq;
 438                 unsigned long freqn = perf->states[0].core_frequency * 1000;
 439
 440                 for (i = 0; i < (perf->state_count-1); i++) {
 441                         freq = freqn;
 442                         freqn = perf->states[i+1].core_frequency * 1000;
 443                         if ((2 * cpu_khz) > (freqn + freq)) {
 444                                 perf->state = i;
 445                                 return freq;
 446                         }
 447                 }
 448                 perf->state = perf->state_count-1;
 449                 return freqn;
 450         } else {
 451                 /* assume CPU is at P0... */
 452                 perf->state = 0;
 453                 return perf->states[0].core_frequency * 1000;
 454         }
 455 }
 456
 457 static void free_acpi_perf_data(void)
 458 {
 459         unsigned int i;
 460
 461         /* Freeing a NULL pointer is OK, and alloc_percpu zeroes. */
 462         for_each_possible_cpu(i)
 463                 free_cpumask_var(per_cpu_ptr(acpi_perf_data, i)
 464                                  ->shared_cpu_map);
 465         free_percpu(acpi_perf_data);
 466 }
 467
 468 /*
 469  * acpi_cpufreq_early_init - initialize ACPI P-States library
 470  *
 471  * Initialize the ACPI P-States library (drivers/acpi/processor_perflib.c)
 472  * in order to determine correct frequency and voltage pairings. We can
 473  * do _PDC and _PSD and find out the processor dependency for the
 474  * actual init that will happen later...
 475  */
 476 static int __init acpi_cpufreq_early_init(void)
 477 {
 478         unsigned int i;
 479         dprintk("acpi_cpufreq_early_init\n");
 480
 481         acpi_perf_data = alloc_percpu(struct acpi_processor_performance);
 482         if (!acpi_perf_data) {
 483                 dprintk("Memory allocation error for acpi_perf_data.\n");
 484                 return -ENOMEM;
 485         }
 486         for_each_possible_cpu(i) {
 487                 if (!zalloc_cpumask_var_node(
 488                         &per_cpu_ptr(acpi_perf_data, i)->shared_cpu_map,
 489                         GFP_KERNEL, cpu_to_node(i))) {
 490
 491                         /* Freeing a NULL pointer is OK: alloc_percpu zeroes. */
 492                         free_acpi_perf_data();
 493                         return -ENOMEM;
 494                 }
 495         }
 496
 497         /* Do initialization in ACPI core */
 498         acpi_processor_preregister_performance(acpi_perf_data);
 499         return 0;
 500 }
 501
 502 #ifdef CONFIG_SMP
 503 /*
 504  * Some BIOSes do SW_ANY coordination internally, either set it up in hw
 505  * or do it in BIOS firmware and won't inform about it to OS. If not
 506  * detected, this has a side effect of making CPU run at a different speed
 507  * than OS intended it to run at. Detect it and handle it cleanly.
 508  */
 509 static int bios_with_sw_any_bug;
 510
 511 static int sw_any_bug_found(const struct dmi_system_id *d)
 512 {
 513         bios_with_sw_any_bug = 1;
 514         return 0;
 515 }
 516
 517 static const struct dmi_system_id sw_any_bug_dmi_table[] = {
 518         {
 519                 .callback = sw_any_bug_found,
 520                 .ident = "Supermicro Server X6DLP",
 521                 .matches = {
 522                         DMI_MATCH(DMI_SYS_VENDOR, "Supermicro"),
 523                         DMI_MATCH(DMI_BIOS_VERSION, "080010"),
 524                         DMI_MATCH(DMI_PRODUCT_NAME, "X6DLP"),
 525                 },
 526         },
 527         { }
 528 };
 529 #endif
 530
 531 static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
 532 {
 533         unsigned int i;
 534         unsigned int valid_states = 0;
 535         unsigned int cpu = policy->cpu;
 536         struct acpi_cpufreq_data *data;
 537         unsigned int result = 0;
 538         struct cpuinfo_x86 *c = &cpu_data(policy->cpu);
 539         struct acpi_processor_performance *perf;
 540
 541         dprintk("acpi_cpufreq_cpu_init\n");
 542
 543         data = kzalloc(sizeof(struct acpi_cpufreq_data), GFP_KERNEL);
 544         if (!data)
 545                 return -ENOMEM;
 546
 547         data->acpi_data = per_cpu_ptr(acpi_perf_data, cpu);
 548         per_cpu(drv_data, cpu) = data;
 549
 550         if (cpu_has(c, X86_FEATURE_CONSTANT_TSC))
 551                 acpi_cpufreq_driver.flags |= CPUFREQ_CONST_LOOPS;
 552
 553         result = acpi_processor_register_performance(data->acpi_data, cpu);
 554         if (result)
 555                 goto err_free;
 556
 557         perf = data->acpi_data;
 558         policy->shared_type = perf->shared_type;
 559
 560         /*
 561          * Will let policy->cpus know about dependency only when software
 562          * coordination is required.
 563          */
 564         if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL ||
 565             policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {
 566                 cpumask_copy(policy->cpus, perf->shared_cpu_map);
 567         }
 568         cpumask_copy(policy->related_cpus, perf->shared_cpu_map);
 569
 570 #ifdef CONFIG_SMP
 571         dmi_check_system(sw_any_bug_dmi_table);
 572         if (bios_with_sw_any_bug && cpumask_weight(policy->cpus) == 1) {
 573                 policy->shared_type = CPUFREQ_SHARED_TYPE_ALL;
 574                 cpumask_copy(policy->cpus, cpu_core_mask(cpu));
 575         }
 576 #endif
 577
 578         /* capability check */
 579         if (perf->state_count <= 1) {
 580                 dprintk("No P-States\n");
 581                 result = -ENODEV;
 582                 goto err_unreg;
 583         }
 584
 585         if (perf->control_register.space_id != perf->status_register.space_id) {
 586                 result = -ENODEV;
 587                 goto err_unreg;
 588         }
 589
 590         switch (perf->control_register.space_id) {
 591         case ACPI_ADR_SPACE_SYSTEM_IO:
 592                 dprintk("SYSTEM IO addr space\n");
 593                 data->cpu_feature = SYSTEM_IO_CAPABLE;
 594                 break;
 595         case ACPI_ADR_SPACE_FIXED_HARDWARE:
 596                 dprintk("HARDWARE addr space\n");
 597                 if (!check_est_cpu(cpu)) {
 598                         result = -ENODEV;
 599                         goto err_unreg;
 600                 }
 601                 data->cpu_feature = SYSTEM_INTEL_MSR_CAPABLE;
 602                 break;
 603         default:
 604                 dprintk("Unknown addr space %d\n",
 605                         (u32) (perf->control_register.space_id));
 606                 result = -ENODEV;
 607                 goto err_unreg;
 608         }
 609
 610         data->freq_table = kmalloc(sizeof(struct cpufreq_frequency_table) *
 611                     (perf->state_count+1), GFP_KERNEL);
 612         if (!data->freq_table) {
 613                 result = -ENOMEM;
 614                 goto err_unreg;
 615         }
 616
 617         /* detect transition latency */
 618         policy->cpuinfo.transition_latency = 0;
 619         for (i = 0; i < perf->state_count; i++) {
 620                 if ((perf->states[i].transition_latency * 1000) >
 621                     policy->cpuinfo.transition_latency)
 622                         policy->cpuinfo.transition_latency =
 623                             perf->states[i].transition_latency * 1000;
 624         }
 625
 626         /* Check for high latency (>20uS) from buggy BIOSes, like on T42 */
 627         if (perf->control_register.space_id == ACPI_ADR_SPACE_FIXED_HARDWARE &&
 628             policy->cpuinfo.transition_latency > 20 * 1000) {
 629                 policy->cpuinfo.transition_latency = 20 * 1000;
 630                 printk_once(KERN_INFO
 631                             "P-state transition latency capped at 20 uS\n");
 632         }
 633
 634         /* table init */
 635         for (i = 0; i < perf->state_count; i++) {
 636                 if (i > 0 && perf->states[i].core_frequency >=
 637                     data->freq_table[valid_states-1].frequency / 1000)
 638                         continue;
 639
 640                 data->freq_table[valid_states].index = i;
 641                 data->freq_table[valid_states].frequency =
 642                     perf->states[i].core_frequency * 1000;
 643                 valid_states++;
 644         }
 645         data->freq_table[valid_states].frequency = CPUFREQ_TABLE_END;
 646         perf->state = 0;
 647
 648         result = cpufreq_frequency_table_cpuinfo(policy, data->freq_table);
 649         if (result)
 650                 goto err_freqfree;
 651
 652         if (perf->states[0].core_frequency * 1000 != policy->cpuinfo.max_freq)
 653                 printk(KERN_WARNING FW_WARN "P-state 0 is not max freq\n");
 654
 655         switch (perf->control_register.space_id) {
 656         case ACPI_ADR_SPACE_SYSTEM_IO:
 657                 /* Current speed is unknown and not detectable by IO port */
 658                 policy->cur = acpi_cpufreq_guess_freq(data, policy->cpu);
 659                 break;
 660         case ACPI_ADR_SPACE_FIXED_HARDWARE:
 661                 acpi_cpufreq_driver.get = get_cur_freq_on_cpu;
 662                 policy->cur = get_cur_freq_on_cpu(cpu);
 663                 break;
 664         default:
 665                 break;
 666         }
 667
 668         /* notify BIOS that we exist */
 669         acpi_processor_notify_smm(THIS_MODULE);
 670
 671         /* Check for APERF/MPERF support in hardware */
 672         if (cpu_has(c, X86_FEATURE_APERFMPERF))
 673                 acpi_cpufreq_driver.getavg = get_measured_perf;
 674
 675         dprintk("CPU%u - ACPI performance management activated.\n", cpu);
 676         for (i = 0; i < perf->state_count; i++)
 677                 dprintk("     %cP%d: %d MHz, %d mW, %d uS\n",
 678                         (i == perf->state ? '*' : ' '), i,
 679                         (u32) perf->states[i].core_frequency,
 680                         (u32) perf->states[i].power,
 681                         (u32) perf->states[i].transition_latency);
 682
 683         cpufreq_frequency_table_get_attr(data->freq_table, policy->cpu);
 684
 685         /*
 686          * the first call to ->target() should result in us actually
 687          * writing something to the appropriate registers.
 688          */
 689         data->resume = 1;
 690
 691         return result;
 692
 693 err_freqfree:
 694         kfree(data->freq_table);
 695 err_unreg:
 696         acpi_processor_unregister_performance(perf, cpu);
 697 err_free:
 698         kfree(data);
 699         per_cpu(drv_data, cpu) = NULL;
 700
 701         return result;
 702 }
 703
 704 static int acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy)
 705 {
 706         struct acpi_cpufreq_data *data = per_cpu(drv_data, policy->cpu);
 707
 708         dprintk("acpi_cpufreq_cpu_exit\n");
 709
 710         if (data) {
 711                 cpufreq_frequency_table_put_attr(policy->cpu);
 712                 per_cpu(drv_data, policy->cpu) = NULL;
 713                 acpi_processor_unregister_performance(data->acpi_data,
 714                                                       policy->cpu);
 715                 kfree(data);
 716         }
 717
 718         return 0;
 719 }
 720
 721 static int acpi_cpufreq_resume(struct cpufreq_policy *policy)
 722 {
 723         struct acpi_cpufreq_data *data = per_cpu(drv_data, policy->cpu);
 724
 725         dprintk("acpi_cpufreq_resume\n");
 726
 727         data->resume = 1;
 728
 729         return 0;
 730 }
 731
 732 static struct freq_attr *acpi_cpufreq_attr[] = {
 733         &cpufreq_freq_attr_scaling_available_freqs,
 734         NULL,
 735 };
 736
 737 static struct cpufreq_driver acpi_cpufreq_driver = {
 738         .verify = acpi_cpufreq_verify,
 739         .target = acpi_cpufreq_target,
 740         .init = acpi_cpufreq_cpu_init,
 741         .exit = acpi_cpufreq_cpu_exit,
 742         .resume = acpi_cpufreq_resume,
 743         .name = "acpi-cpufreq",
 744         .owner = THIS_MODULE,
 745         .attr = acpi_cpufreq_attr,
 746 };
 747
 748 static int __init acpi_cpufreq_init(void)
 749 {
 750         int ret;
 751
 752         if (acpi_disabled)
 753                 return 0;
 754
 755         dprintk("acpi_cpufreq_init\n");
 756
 757         ret = acpi_cpufreq_early_init();
 758         if (ret)
 759                 return ret;
 760
 761         ret = cpufreq_register_driver(&acpi_cpufreq_driver);
 762         if (ret)
 763                 free_acpi_perf_data();
 764
 765         return ret;
 766 }
 767
 768 static void __exit acpi_cpufreq_exit(void)
 769 {
 770         dprintk("acpi_cpufreq_exit\n");
 771
 772         cpufreq_unregister_driver(&acpi_cpufreq_driver);
 773
 774         free_percpu(acpi_perf_data);
 775 }
 776
 777 module_param(acpi_pstate_strict, uint, 0644);
 778 MODULE_PARM_DESC(acpi_pstate_strict,
 779         "value 0 or non-zero. non-zero -> strict ACPI checks are "
 780         "performed during frequency changes.");
 781
 782 late_initcall(acpi_cpufreq_init);
 783 module_exit(acpi_cpufreq_exit);
 784
 785 MODULE_ALIAS("acpi");