arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c

   1 /*
   2  * acpi-cpufreq.c - ACPI Processor P-States Driver ($Revision: 1.4 $)
   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/ftrace.h>
  37
  38 #include <linux/acpi.h>
  39 #include <acpi/processor.h>
  40
  41 #include <asm/io.h>
  42 #include <asm/msr.h>
  43 #include <asm/processor.h>
  44 #include <asm/cpufeature.h>
  45 #include <asm/delay.h>
  46 #include <asm/uaccess.h>
  47
  48 #define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_DRIVER, "acpi-cpufreq", msg)
  49
  50 MODULE_AUTHOR("Paul Diefenbaugh, Dominik Brodowski");
  51 MODULE_DESCRIPTION("ACPI Processor P-States Driver");
  52 MODULE_LICENSE("GPL");
  53
  54 enum {
  55         UNDEFINED_CAPABLE = 0,
  56         SYSTEM_INTEL_MSR_CAPABLE,
  57         SYSTEM_IO_CAPABLE,
  58 };
  59
  60 #define INTEL_MSR_RANGE         (0xffff)
  61 #define CPUID_6_ECX_APERFMPERF_CAPABILITY       (0x1)
  62
  63 struct acpi_cpufreq_data {
  64         struct acpi_processor_performance *acpi_data;
  65         struct cpufreq_frequency_table *freq_table;
  66         unsigned int max_freq;
  67         unsigned int resume;
  68         unsigned int cpu_feature;
  69 };
  70
  71 static DEFINE_PER_CPU(struct acpi_cpufreq_data *, drv_data);
  72
  73 /* acpi_perf_data is a pointer to percpu data. */
  74 static struct acpi_processor_performance *acpi_perf_data;
  75
  76 static struct cpufreq_driver acpi_cpufreq_driver;
  77
  78 static unsigned int acpi_pstate_strict;
  79
  80 static int check_est_cpu(unsigned int cpuid)
  81 {
  82         struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
  83
  84         if (cpu->x86_vendor != X86_VENDOR_INTEL ||
  85             !cpu_has(cpu, X86_FEATURE_EST))
  86                 return 0;
  87
  88         return 1;
  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 typedef union {
 142         struct msr_addr msr;
 143         struct io_addr io;
 144 } drv_addr_union;
 145
 146 struct drv_cmd {
 147         unsigned int type;
 148         cpumask_t mask;
 149         drv_addr_union addr;
 150         u32 val;
 151 };
 152
 153 static void do_drv_read(struct drv_cmd *cmd)
 154 {
 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 static void do_drv_write(struct drv_cmd *cmd)
 172 {
 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         cpumask_t saved_mask = current->cpus_allowed;
 194         cmd->val = 0;
 195
 196         set_cpus_allowed_ptr(current, &cmd->mask);
 197         do_drv_read(cmd);
 198         set_cpus_allowed_ptr(current, &saved_mask);
 199 }
 200
 201 static void drv_write(struct drv_cmd *cmd)
 202 {
 203         cpumask_t saved_mask = current->cpus_allowed;
 204         unsigned int i;
 205
 206         for_each_cpu_mask_nr(i, cmd->mask) {
 207                 set_cpus_allowed_ptr(current, &cpumask_of_cpu(i));
 208                 do_drv_write(cmd);
 209         }
 210
 211         set_cpus_allowed_ptr(current, &saved_mask);
 212         return;
 213 }
 214
 215 static u32 get_cur_val(const cpumask_t *mask)
 216 {
 217         struct acpi_processor_performance *perf;
 218         struct drv_cmd cmd;
 219
 220         if (unlikely(cpus_empty(*mask)))
 221                 return 0;
 222
 223         switch (per_cpu(drv_data, first_cpu(*mask))->cpu_feature) {
 224         case SYSTEM_INTEL_MSR_CAPABLE:
 225                 cmd.type = SYSTEM_INTEL_MSR_CAPABLE;
 226                 cmd.addr.msr.reg = MSR_IA32_PERF_STATUS;
 227                 break;
 228         case SYSTEM_IO_CAPABLE:
 229                 cmd.type = SYSTEM_IO_CAPABLE;
 230                 perf = per_cpu(drv_data, first_cpu(*mask))->acpi_data;
 231                 cmd.addr.io.port = perf->control_register.address;
 232                 cmd.addr.io.bit_width = perf->control_register.bit_width;
 233                 break;
 234         default:
 235                 return 0;
 236         }
 237
 238         cmd.mask = *mask;
 239
 240         drv_read(&cmd);
 241
 242         dprintk("get_cur_val = %u\n", cmd.val);
 243
 244         return cmd.val;
 245 }
 246
 247 /*
 248  * Return the measured active (C0) frequency on this CPU since last call
 249  * to this function.
 250  * Input: cpu number
 251  * Return: Average CPU frequency in terms of max frequency (zero on error)
 252  *
 253  * We use IA32_MPERF and IA32_APERF MSRs to get the measured performance
 254  * over a period of time, while CPU is in C0 state.
 255  * IA32_MPERF counts at the rate of max advertised frequency
 256  * IA32_APERF counts at the rate of actual CPU frequency
 257  * Only IA32_APERF/IA32_MPERF ratio is architecturally defined and
 258  * no meaning should be associated with absolute values of these MSRs.
 259  */
 260 static unsigned int get_measured_perf(struct cpufreq_policy *policy,
 261                                       unsigned int cpu)
 262 {
 263         union {
 264                 struct {
 265                         u32 lo;
 266                         u32 hi;
 267                 } split;
 268                 u64 whole;
 269         } aperf_cur, mperf_cur;
 270
 271         cpumask_t saved_mask;
 272         unsigned int perf_percent;
 273         unsigned int retval;
 274
 275         saved_mask = current->cpus_allowed;
 276         set_cpus_allowed_ptr(current, &cpumask_of_cpu(cpu));
 277         if (get_cpu() != cpu) {
 278                 /* We were not able to run on requested processor */
 279                 put_cpu();
 280                 return 0;
 281         }
 282
 283         rdmsr(MSR_IA32_APERF, aperf_cur.split.lo, aperf_cur.split.hi);
 284         rdmsr(MSR_IA32_MPERF, mperf_cur.split.lo, mperf_cur.split.hi);
 285
 286         wrmsr(MSR_IA32_APERF, 0,0);
 287         wrmsr(MSR_IA32_MPERF, 0,0);
 288
 289 #ifdef __i386__
 290         /*
 291          * We dont want to do 64 bit divide with 32 bit kernel
 292          * Get an approximate value. Return failure in case we cannot get
 293          * an approximate value.
 294          */
 295         if (unlikely(aperf_cur.split.hi || mperf_cur.split.hi)) {
 296                 int shift_count;
 297                 u32 h;
 298
 299                 h = max_t(u32, aperf_cur.split.hi, mperf_cur.split.hi);
 300                 shift_count = fls(h);
 301
 302                 aperf_cur.whole >>= shift_count;
 303                 mperf_cur.whole >>= shift_count;
 304         }
 305
 306         if (((unsigned long)(-1) / 100) < aperf_cur.split.lo) {
 307                 int shift_count = 7;
 308                 aperf_cur.split.lo >>= shift_count;
 309                 mperf_cur.split.lo >>= shift_count;
 310         }
 311
 312         if (aperf_cur.split.lo && mperf_cur.split.lo)
 313                 perf_percent = (aperf_cur.split.lo * 100) / mperf_cur.split.lo;
 314         else
 315                 perf_percent = 0;
 316
 317 #else
 318         if (unlikely(((unsigned long)(-1) / 100) < aperf_cur.whole)) {
 319                 int shift_count = 7;
 320                 aperf_cur.whole >>= shift_count;
 321                 mperf_cur.whole >>= shift_count;
 322         }
 323
 324         if (aperf_cur.whole && mperf_cur.whole)
 325                 perf_percent = (aperf_cur.whole * 100) / mperf_cur.whole;
 326         else
 327                 perf_percent = 0;
 328
 329 #endif
 330
 331         retval = per_cpu(drv_data, policy->cpu)->max_freq * perf_percent / 100;
 332
 333         put_cpu();
 334         set_cpus_allowed_ptr(current, &saved_mask);
 335
 336         dprintk("cpu %d: performance percent %d\n", cpu, perf_percent);
 337         return retval;
 338 }
 339
 340 static unsigned int get_cur_freq_on_cpu(unsigned int cpu)
 341 {
 342         struct acpi_cpufreq_data *data = per_cpu(drv_data, cpu);
 343         unsigned int freq;
 344         unsigned int cached_freq;
 345
 346         dprintk("get_cur_freq_on_cpu (%d)\n", cpu);
 347
 348         if (unlikely(data == NULL ||
 349                      data->acpi_data == NULL || data->freq_table == NULL)) {
 350                 return 0;
 351         }
 352
 353         cached_freq = data->freq_table[data->acpi_data->state].frequency;
 354         freq = extract_freq(get_cur_val(&cpumask_of_cpu(cpu)), data);
 355         if (freq != cached_freq) {
 356                 /*
 357                  * The dreaded BIOS frequency change behind our back.
 358                  * Force set the frequency on next target call.
 359                  */
 360                 data->resume = 1;
 361         }
 362
 363         dprintk("cur freq = %u\n", freq);
 364
 365         return freq;
 366 }
 367
 368 static unsigned int check_freqs(const cpumask_t *mask, unsigned int freq,
 369                                 struct acpi_cpufreq_data *data)
 370 {
 371         unsigned int cur_freq;
 372         unsigned int i;
 373
 374         for (i=0; i<100; i++) {
 375                 cur_freq = extract_freq(get_cur_val(mask), data);
 376                 if (cur_freq == freq)
 377                         return 1;
 378                 udelay(10);
 379         }
 380         return 0;
 381 }
 382
 383 static int acpi_cpufreq_target(struct cpufreq_policy *policy,
 384                                unsigned int target_freq, unsigned int relation)
 385 {
 386         struct acpi_cpufreq_data *data = per_cpu(drv_data, policy->cpu);
 387         struct acpi_processor_performance *perf;
 388         struct cpufreq_freqs freqs;
 389         cpumask_t online_policy_cpus;
 390         struct drv_cmd cmd;
 391         unsigned int next_state = 0; /* Index into freq_table */
 392         unsigned int next_perf_state = 0; /* Index into perf table */
 393         unsigned int i;
 394         int result = 0;
 395         struct power_trace it;
 396
 397         dprintk("acpi_cpufreq_target %d (%d)\n", target_freq, policy->cpu);
 398
 399         if (unlikely(data == NULL ||
 400              data->acpi_data == NULL || data->freq_table == NULL)) {
 401                 return -ENODEV;
 402         }
 403
 404         perf = data->acpi_data;
 405         result = cpufreq_frequency_table_target(policy,
 406                                                 data->freq_table,
 407                                                 target_freq,
 408                                                 relation, &next_state);
 409         if (unlikely(result))
 410                 return -ENODEV;
 411
 412 #ifdef CONFIG_HOTPLUG_CPU
 413         /* cpufreq holds the hotplug lock, so we are safe from here on */
 414         cpus_and(online_policy_cpus, cpu_online_map, policy->cpus);
 415 #else
 416         online_policy_cpus = policy->cpus;
 417 #endif
 418
 419         next_perf_state = data->freq_table[next_state].index;
 420         if (perf->state == next_perf_state) {
 421                 if (unlikely(data->resume)) {
 422                         dprintk("Called after resume, resetting to P%d\n",
 423                                 next_perf_state);
 424                         data->resume = 0;
 425                 } else {
 426                         dprintk("Already at target state (P%d)\n",
 427                                 next_perf_state);
 428                         return 0;
 429                 }
 430         }
 431
 432         trace_power_mark(&it, POWER_PSTATE, next_perf_state);
 433
 434         switch (data->cpu_feature) {
 435         case SYSTEM_INTEL_MSR_CAPABLE:
 436                 cmd.type = SYSTEM_INTEL_MSR_CAPABLE;
 437                 cmd.addr.msr.reg = MSR_IA32_PERF_CTL;
 438                 cmd.val = (u32) perf->states[next_perf_state].control;
 439                 break;
 440         case SYSTEM_IO_CAPABLE:
 441                 cmd.type = SYSTEM_IO_CAPABLE;
 442                 cmd.addr.io.port = perf->control_register.address;
 443                 cmd.addr.io.bit_width = perf->control_register.bit_width;
 444                 cmd.val = (u32) perf->states[next_perf_state].control;
 445                 break;
 446         default:
 447                 return -ENODEV;
 448         }
 449
 450         cpus_clear(cmd.mask);
 451
 452         if (policy->shared_type != CPUFREQ_SHARED_TYPE_ANY)
 453                 cmd.mask = online_policy_cpus;
 454         else
 455                 cpu_set(policy->cpu, cmd.mask);
 456
 457         freqs.old = perf->states[perf->state].core_frequency * 1000;
 458         freqs.new = data->freq_table[next_state].frequency;
 459         for_each_cpu_mask_nr(i, cmd.mask) {
 460                 freqs.cpu = i;
 461                 cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
 462         }
 463
 464         drv_write(&cmd);
 465
 466         if (acpi_pstate_strict) {
 467                 if (!check_freqs(&cmd.mask, freqs.new, data)) {
 468                         dprintk("acpi_cpufreq_target failed (%d)\n",
 469                                 policy->cpu);
 470                         return -EAGAIN;
 471                 }
 472         }
 473
 474         for_each_cpu_mask_nr(i, cmd.mask) {
 475                 freqs.cpu = i;
 476                 cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
 477         }
 478         perf->state = next_perf_state;
 479
 480         return result;
 481 }
 482
 483 static int acpi_cpufreq_verify(struct cpufreq_policy *policy)
 484 {
 485         struct acpi_cpufreq_data *data = per_cpu(drv_data, policy->cpu);
 486
 487         dprintk("acpi_cpufreq_verify\n");
 488
 489         return cpufreq_frequency_table_verify(policy, data->freq_table);
 490 }
 491
 492 static unsigned long
 493 acpi_cpufreq_guess_freq(struct acpi_cpufreq_data *data, unsigned int cpu)
 494 {
 495         struct acpi_processor_performance *perf = data->acpi_data;
 496
 497         if (cpu_khz) {
 498                 /* search the closest match to cpu_khz */
 499                 unsigned int i;
 500                 unsigned long freq;
 501                 unsigned long freqn = perf->states[0].core_frequency * 1000;
 502
 503                 for (i=0; i<(perf->state_count-1); i++) {
 504                         freq = freqn;
 505                         freqn = perf->states[i+1].core_frequency * 1000;
 506                         if ((2 * cpu_khz) > (freqn + freq)) {
 507                                 perf->state = i;
 508                                 return freq;
 509                         }
 510                 }
 511                 perf->state = perf->state_count-1;
 512                 return freqn;
 513         } else {
 514                 /* assume CPU is at P0... */
 515                 perf->state = 0;
 516                 return perf->states[0].core_frequency * 1000;
 517         }
 518 }
 519
 520 /*
 521  * acpi_cpufreq_early_init - initialize ACPI P-States library
 522  *
 523  * Initialize the ACPI P-States library (drivers/acpi/processor_perflib.c)
 524  * in order to determine correct frequency and voltage pairings. We can
 525  * do _PDC and _PSD and find out the processor dependency for the
 526  * actual init that will happen later...
 527  */
 528 static int __init acpi_cpufreq_early_init(void)
 529 {
 530         dprintk("acpi_cpufreq_early_init\n");
 531
 532         acpi_perf_data = alloc_percpu(struct acpi_processor_performance);
 533         if (!acpi_perf_data) {
 534                 dprintk("Memory allocation error for acpi_perf_data.\n");
 535                 return -ENOMEM;
 536         }
 537
 538         /* Do initialization in ACPI core */
 539         acpi_processor_preregister_performance(acpi_perf_data);
 540         return 0;
 541 }
 542
 543 #ifdef CONFIG_SMP
 544 /*
 545  * Some BIOSes do SW_ANY coordination internally, either set it up in hw
 546  * or do it in BIOS firmware and won't inform about it to OS. If not
 547  * detected, this has a side effect of making CPU run at a different speed
 548  * than OS intended it to run at. Detect it and handle it cleanly.
 549  */
 550 static int bios_with_sw_any_bug;
 551
 552 static int sw_any_bug_found(const struct dmi_system_id *d)
 553 {
 554         bios_with_sw_any_bug = 1;
 555         return 0;
 556 }
 557
 558 static const struct dmi_system_id sw_any_bug_dmi_table[] = {
 559         {
 560                 .callback = sw_any_bug_found,
 561                 .ident = "Supermicro Server X6DLP",
 562                 .matches = {
 563                         DMI_MATCH(DMI_SYS_VENDOR, "Supermicro"),
 564                         DMI_MATCH(DMI_BIOS_VERSION, "080010"),
 565                         DMI_MATCH(DMI_PRODUCT_NAME, "X6DLP"),
 566                 },
 567         },
 568         { }
 569 };
 570 #endif
 571
 572 static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
 573 {
 574         unsigned int i;
 575         unsigned int valid_states = 0;
 576         unsigned int cpu = policy->cpu;
 577         struct acpi_cpufreq_data *data;
 578         unsigned int result = 0;
 579         struct cpuinfo_x86 *c = &cpu_data(policy->cpu);
 580         struct acpi_processor_performance *perf;
 581
 582         dprintk("acpi_cpufreq_cpu_init\n");
 583
 584         data = kzalloc(sizeof(struct acpi_cpufreq_data), GFP_KERNEL);
 585         if (!data)
 586                 return -ENOMEM;
 587
 588         data->acpi_data = percpu_ptr(acpi_perf_data, cpu);
 589         per_cpu(drv_data, cpu) = data;
 590
 591         if (cpu_has(c, X86_FEATURE_CONSTANT_TSC))
 592                 acpi_cpufreq_driver.flags |= CPUFREQ_CONST_LOOPS;
 593
 594         result = acpi_processor_register_performance(data->acpi_data, cpu);
 595         if (result)
 596                 goto err_free;
 597
 598         perf = data->acpi_data;
 599         policy->shared_type = perf->shared_type;
 600
 601         /*
 602          * Will let policy->cpus know about dependency only when software
 603          * coordination is required.
 604          */
 605         if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL ||
 606             policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {
 607                 policy->cpus = perf->shared_cpu_map;
 608         }
 609         policy->related_cpus = perf->shared_cpu_map;
 610
 611 #ifdef CONFIG_SMP
 612         dmi_check_system(sw_any_bug_dmi_table);
 613         if (bios_with_sw_any_bug && cpus_weight(policy->cpus) == 1) {
 614                 policy->shared_type = CPUFREQ_SHARED_TYPE_ALL;
 615                 policy->cpus = per_cpu(cpu_core_map, cpu);
 616         }
 617 #endif
 618
 619         /* capability check */
 620         if (perf->state_count <= 1) {
 621                 dprintk("No P-States\n");
 622                 result = -ENODEV;
 623                 goto err_unreg;
 624         }
 625
 626         if (perf->control_register.space_id != perf->status_register.space_id) {
 627                 result = -ENODEV;
 628                 goto err_unreg;
 629         }
 630
 631         switch (perf->control_register.space_id) {
 632         case ACPI_ADR_SPACE_SYSTEM_IO:
 633                 dprintk("SYSTEM IO addr space\n");
 634                 data->cpu_feature = SYSTEM_IO_CAPABLE;
 635                 break;
 636         case ACPI_ADR_SPACE_FIXED_HARDWARE:
 637                 dprintk("HARDWARE addr space\n");
 638                 if (!check_est_cpu(cpu)) {
 639                         result = -ENODEV;
 640                         goto err_unreg;
 641                 }
 642                 data->cpu_feature = SYSTEM_INTEL_MSR_CAPABLE;
 643                 break;
 644         default:
 645                 dprintk("Unknown addr space %d\n",
 646                         (u32) (perf->control_register.space_id));
 647                 result = -ENODEV;
 648                 goto err_unreg;
 649         }
 650
 651         data->freq_table = kmalloc(sizeof(struct cpufreq_frequency_table) *
 652                     (perf->state_count+1), GFP_KERNEL);
 653         if (!data->freq_table) {
 654                 result = -ENOMEM;
 655                 goto err_unreg;
 656         }
 657
 658         /* detect transition latency */
 659         policy->cpuinfo.transition_latency = 0;
 660         for (i=0; i<perf->state_count; i++) {
 661                 if ((perf->states[i].transition_latency * 1000) >
 662                     policy->cpuinfo.transition_latency)
 663                         policy->cpuinfo.transition_latency =
 664                             perf->states[i].transition_latency * 1000;
 665         }
 666
 667         data->max_freq = perf->states[0].core_frequency * 1000;
 668         /* table init */
 669         for (i=0; i<perf->state_count; i++) {
 670                 if (i>0 && perf->states[i].core_frequency >=
 671                     data->freq_table[valid_states-1].frequency / 1000)
 672                         continue;
 673
 674                 data->freq_table[valid_states].index = i;
 675                 data->freq_table[valid_states].frequency =
 676                     perf->states[i].core_frequency * 1000;
 677                 valid_states++;
 678         }
 679         data->freq_table[valid_states].frequency = CPUFREQ_TABLE_END;
 680         perf->state = 0;
 681
 682         result = cpufreq_frequency_table_cpuinfo(policy, data->freq_table);
 683         if (result)
 684                 goto err_freqfree;
 685
 686         switch (perf->control_register.space_id) {
 687         case ACPI_ADR_SPACE_SYSTEM_IO:
 688                 /* Current speed is unknown and not detectable by IO port */
 689                 policy->cur = acpi_cpufreq_guess_freq(data, policy->cpu);
 690                 break;
 691         case ACPI_ADR_SPACE_FIXED_HARDWARE:
 692                 acpi_cpufreq_driver.get = get_cur_freq_on_cpu;
 693                 policy->cur = get_cur_freq_on_cpu(cpu);
 694                 break;
 695         default:
 696                 break;
 697         }
 698
 699         /* notify BIOS that we exist */
 700         acpi_processor_notify_smm(THIS_MODULE);
 701
 702         /* Check for APERF/MPERF support in hardware */
 703         if (c->x86_vendor == X86_VENDOR_INTEL && c->cpuid_level >= 6) {
 704                 unsigned int ecx;
 705                 ecx = cpuid_ecx(6);
 706                 if (ecx & CPUID_6_ECX_APERFMPERF_CAPABILITY)
 707                         acpi_cpufreq_driver.getavg = get_measured_perf;
 708         }
 709
 710         dprintk("CPU%u - ACPI performance management activated.\n", cpu);
 711         for (i = 0; i < perf->state_count; i++)
 712                 dprintk("     %cP%d: %d MHz, %d mW, %d uS\n",
 713                         (i == perf->state ? '*' : ' '), i,
 714                         (u32) perf->states[i].core_frequency,
 715                         (u32) perf->states[i].power,
 716                         (u32) perf->states[i].transition_latency);
 717
 718         cpufreq_frequency_table_get_attr(data->freq_table, policy->cpu);
 719
 720         /*
 721          * the first call to ->target() should result in us actually
 722          * writing something to the appropriate registers.
 723          */
 724         data->resume = 1;
 725
 726         return result;
 727
 728 err_freqfree:
 729         kfree(data->freq_table);
 730 err_unreg:
 731         acpi_processor_unregister_performance(perf, cpu);
 732 err_free:
 733         kfree(data);
 734         per_cpu(drv_data, cpu) = NULL;
 735
 736         return result;
 737 }
 738
 739 static int acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy)
 740 {
 741         struct acpi_cpufreq_data *data = per_cpu(drv_data, policy->cpu);
 742
 743         dprintk("acpi_cpufreq_cpu_exit\n");
 744
 745         if (data) {
 746                 cpufreq_frequency_table_put_attr(policy->cpu);
 747                 per_cpu(drv_data, policy->cpu) = NULL;
 748                 acpi_processor_unregister_performance(data->acpi_data,
 749                                                       policy->cpu);
 750                 kfree(data);
 751         }
 752
 753         return 0;
 754 }
 755
 756 static int acpi_cpufreq_resume(struct cpufreq_policy *policy)
 757 {
 758         struct acpi_cpufreq_data *data = per_cpu(drv_data, policy->cpu);
 759
 760         dprintk("acpi_cpufreq_resume\n");
 761
 762         data->resume = 1;
 763
 764         return 0;
 765 }
 766
 767 static struct freq_attr *acpi_cpufreq_attr[] = {
 768         &cpufreq_freq_attr_scaling_available_freqs,
 769         NULL,
 770 };
 771
 772 static struct cpufreq_driver acpi_cpufreq_driver = {
 773         .verify = acpi_cpufreq_verify,
 774         .target = acpi_cpufreq_target,
 775         .init = acpi_cpufreq_cpu_init,
 776         .exit = acpi_cpufreq_cpu_exit,
 777         .resume = acpi_cpufreq_resume,
 778         .name = "acpi-cpufreq",
 779         .owner = THIS_MODULE,
 780         .attr = acpi_cpufreq_attr,
 781 };
 782
 783 static int __init acpi_cpufreq_init(void)
 784 {
 785         int ret;
 786
 787         if (acpi_disabled)
 788                 return 0;
 789
 790         dprintk("acpi_cpufreq_init\n");
 791
 792         ret = acpi_cpufreq_early_init();
 793         if (ret)
 794                 return ret;
 795
 796         ret = cpufreq_register_driver(&acpi_cpufreq_driver);
 797         if (ret)
 798                 free_percpu(acpi_perf_data);
 799
 800         return ret;
 801 }
 802
 803 static void __exit acpi_cpufreq_exit(void)
 804 {
 805         dprintk("acpi_cpufreq_exit\n");
 806
 807         cpufreq_unregister_driver(&acpi_cpufreq_driver);
 808
 809         free_percpu(acpi_perf_data);
 810 }
 811
 812 module_param(acpi_pstate_strict, uint, 0644);
 813 MODULE_PARM_DESC(acpi_pstate_strict,
 814         "value 0 or non-zero. non-zero -> strict ACPI checks are "
 815         "performed during frequency changes.");
 816
 817 late_initcall(acpi_cpufreq_init);
 818 module_exit(acpi_cpufreq_exit);
 819
 820 MODULE_ALIAS("acpi");