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         const struct cpumask *mask;
 149         drv_addr_union addr;
 150         u32 val;
 151 };
 152
 153 static long do_drv_read(void *_cmd)
 154 {
 155         struct drv_cmd *cmd = _cmd;
 156         u32 h;
 157
 158         switch (cmd->type) {
 159         case SYSTEM_INTEL_MSR_CAPABLE:
 160                 rdmsr(cmd->addr.msr.reg, cmd->val, h);
 161                 break;
 162         case SYSTEM_IO_CAPABLE:
 163                 acpi_os_read_port((acpi_io_address)cmd->addr.io.port,
 164                                 &cmd->val,
 165                                 (u32)cmd->addr.io.bit_width);
 166                 break;
 167         default:
 168                 break;
 169         }
 170         return 0;
 171 }
 172
 173 static long do_drv_write(void *_cmd)
 174 {
 175         struct drv_cmd *cmd = _cmd;
 176         u32 lo, hi;
 177
 178         switch (cmd->type) {
 179         case SYSTEM_INTEL_MSR_CAPABLE:
 180                 rdmsr(cmd->addr.msr.reg, lo, hi);
 181                 lo = (lo & ~INTEL_MSR_RANGE) | (cmd->val & INTEL_MSR_RANGE);
 182                 wrmsr(cmd->addr.msr.reg, lo, hi);
 183                 break;
 184         case SYSTEM_IO_CAPABLE:
 185                 acpi_os_write_port((acpi_io_address)cmd->addr.io.port,
 186                                 cmd->val,
 187                                 (u32)cmd->addr.io.bit_width);
 188                 break;
 189         default:
 190                 break;
 191         }
 192         return 0;
 193 }
 194
 195 static void drv_read(struct drv_cmd *cmd)
 196 {
 197         cmd->val = 0;
 198
 199         work_on_cpu(cpumask_any(cmd->mask), do_drv_read, cmd);
 200 }
 201
 202 static void drv_write(struct drv_cmd *cmd)
 203 {
 204         unsigned int i;
 205
 206         for_each_cpu(i, cmd->mask) {
 207                 work_on_cpu(i, do_drv_write, cmd);
 208         }
 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 struct perf_cur {
 243         union {
 244                 struct {
 245                         u32 lo;
 246                         u32 hi;
 247                 } split;
 248                 u64 whole;
 249         } aperf_cur, mperf_cur;
 250 };
 251
 252
 253 static long read_measured_perf_ctrs(void *_cur)
 254 {
 255         struct perf_cur *cur = _cur;
 256
 257         rdmsr(MSR_IA32_APERF, cur->aperf_cur.split.lo, cur->aperf_cur.split.hi);
 258         rdmsr(MSR_IA32_MPERF, cur->mperf_cur.split.lo, cur->mperf_cur.split.hi);
 259
 260         wrmsr(MSR_IA32_APERF, 0, 0);
 261         wrmsr(MSR_IA32_MPERF, 0, 0);
 262
 263         return 0;
 264 }
 265
 266 /*
 267  * Return the measured active (C0) frequency on this CPU since last call
 268  * to this function.
 269  * Input: cpu number
 270  * Return: Average CPU frequency in terms of max frequency (zero on error)
 271  *
 272  * We use IA32_MPERF and IA32_APERF MSRs to get the measured performance
 273  * over a period of time, while CPU is in C0 state.
 274  * IA32_MPERF counts at the rate of max advertised frequency
 275  * IA32_APERF counts at the rate of actual CPU frequency
 276  * Only IA32_APERF/IA32_MPERF ratio is architecturally defined and
 277  * no meaning should be associated with absolute values of these MSRs.
 278  */
 279 static unsigned int get_measured_perf(struct cpufreq_policy *policy,
 280                                       unsigned int cpu)
 281 {
 282         struct perf_cur cur;
 283         unsigned int perf_percent;
 284         unsigned int retval;
 285
 286         if (!work_on_cpu(cpu, read_measured_perf_ctrs, &cur))
 287                 return 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(cur.aperf_cur.split.hi || cur.mperf_cur.split.hi)) {
 296                 int shift_count;
 297                 u32 h;
 298
 299                 h = max_t(u32, cur.aperf_cur.split.hi, cur.mperf_cur.split.hi);
 300                 shift_count = fls(h);
 301
 302                 cur.aperf_cur.whole >>= shift_count;
 303                 cur.mperf_cur.whole >>= shift_count;
 304         }
 305
 306         if (((unsigned long)(-1) / 100) < cur.aperf_cur.split.lo) {
 307                 int shift_count = 7;
 308                 cur.aperf_cur.split.lo >>= shift_count;
 309                 cur.mperf_cur.split.lo >>= shift_count;
 310         }
 311
 312         if (cur.aperf_cur.split.lo && cur.mperf_cur.split.lo)
 313                 perf_percent = (cur.aperf_cur.split.lo * 100) /
 314                                 cur.mperf_cur.split.lo;
 315         else
 316                 perf_percent = 0;
 317
 318 #else
 319         if (unlikely(((unsigned long)(-1) / 100) < cur.aperf_cur.whole)) {
 320                 int shift_count = 7;
 321                 cur.aperf_cur.whole >>= shift_count;
 322                 cur.mperf_cur.whole >>= shift_count;
 323         }
 324
 325         if (cur.aperf_cur.whole && cur.mperf_cur.whole)
 326                 perf_percent = (cur.aperf_cur.whole * 100) /
 327                                 cur.mperf_cur.whole;
 328         else
 329                 perf_percent = 0;
 330
 331 #endif
 332
 333         retval = per_cpu(drv_data, policy->cpu)->max_freq * perf_percent / 100;
 334
 335         return retval;
 336 }
 337
 338 static unsigned int get_cur_freq_on_cpu(unsigned int cpu)
 339 {
 340         struct acpi_cpufreq_data *data = per_cpu(drv_data, cpu);
 341         unsigned int freq;
 342         unsigned int cached_freq;
 343
 344         dprintk("get_cur_freq_on_cpu (%d)\n", cpu);
 345
 346         if (unlikely(data == NULL ||
 347                      data->acpi_data == NULL || data->freq_table == NULL)) {
 348                 return 0;
 349         }
 350
 351         cached_freq = data->freq_table[data->acpi_data->state].frequency;
 352         freq = extract_freq(get_cur_val(cpumask_of(cpu)), data);
 353         if (freq != cached_freq) {
 354                 /*
 355                  * The dreaded BIOS frequency change behind our back.
 356                  * Force set the frequency on next target call.
 357                  */
 358                 data->resume = 1;
 359         }
 360
 361         dprintk("cur freq = %u\n", freq);
 362
 363         return freq;
 364 }
 365
 366 static unsigned int check_freqs(const struct cpumask *mask, unsigned int freq,
 367                                 struct acpi_cpufreq_data *data)
 368 {
 369         unsigned int cur_freq;
 370         unsigned int i;
 371
 372         for (i=0; i<100; i++) {
 373                 cur_freq = extract_freq(get_cur_val(mask), data);
 374                 if (cur_freq == freq)
 375                         return 1;
 376                 udelay(10);
 377         }
 378         return 0;
 379 }
 380
 381 static int acpi_cpufreq_target(struct cpufreq_policy *policy,
 382                                unsigned int target_freq, unsigned int relation)
 383 {
 384         struct acpi_cpufreq_data *data = per_cpu(drv_data, policy->cpu);
 385         struct acpi_processor_performance *perf;
 386         struct cpufreq_freqs freqs;
 387         struct drv_cmd cmd;
 388         unsigned int next_state = 0; /* Index into freq_table */
 389         unsigned int next_perf_state = 0; /* Index into perf table */
 390         unsigned int i;
 391         int result = 0;
 392         struct power_trace it;
 393
 394         dprintk("acpi_cpufreq_target %d (%d)\n", target_freq, policy->cpu);
 395
 396         if (unlikely(data == NULL ||
 397              data->acpi_data == NULL || data->freq_table == NULL)) {
 398                 return -ENODEV;
 399         }
 400
 401         perf = data->acpi_data;
 402         result = cpufreq_frequency_table_target(policy,
 403                                                 data->freq_table,
 404                                                 target_freq,
 405                                                 relation, &next_state);
 406         if (unlikely(result)) {
 407                 result = -ENODEV;
 408                 goto out;
 409         }
 410
 411         next_perf_state = data->freq_table[next_state].index;
 412         if (perf->state == next_perf_state) {
 413                 if (unlikely(data->resume)) {
 414                         dprintk("Called after resume, resetting to P%d\n",
 415                                 next_perf_state);
 416                         data->resume = 0;
 417                 } else {
 418                         dprintk("Already at target state (P%d)\n",
 419                                 next_perf_state);
 420                         goto out;
 421                 }
 422         }
 423
 424         trace_power_mark(&it, POWER_PSTATE, next_perf_state);
 425
 426         switch (data->cpu_feature) {
 427         case SYSTEM_INTEL_MSR_CAPABLE:
 428                 cmd.type = SYSTEM_INTEL_MSR_CAPABLE;
 429                 cmd.addr.msr.reg = MSR_IA32_PERF_CTL;
 430                 cmd.val = (u32) perf->states[next_perf_state].control;
 431                 break;
 432         case SYSTEM_IO_CAPABLE:
 433                 cmd.type = SYSTEM_IO_CAPABLE;
 434                 cmd.addr.io.port = perf->control_register.address;
 435                 cmd.addr.io.bit_width = perf->control_register.bit_width;
 436                 cmd.val = (u32) perf->states[next_perf_state].control;
 437                 break;
 438         default:
 439                 result = -ENODEV;
 440                 goto out;
 441         }
 442
 443         /* cpufreq holds the hotplug lock, so we are safe from here on */
 444         if (policy->shared_type != CPUFREQ_SHARED_TYPE_ANY)
 445                 cmd.mask = policy->cpus;
 446         else
 447                 cmd.mask = cpumask_of(policy->cpu);
 448
 449         freqs.old = perf->states[perf->state].core_frequency * 1000;
 450         freqs.new = data->freq_table[next_state].frequency;
 451         for_each_cpu(i, cmd.mask) {
 452                 freqs.cpu = i;
 453                 cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
 454         }
 455
 456         drv_write(&cmd);
 457
 458         if (acpi_pstate_strict) {
 459                 if (!check_freqs(cmd.mask, freqs.new, data)) {
 460                         dprintk("acpi_cpufreq_target failed (%d)\n",
 461                                 policy->cpu);
 462                         result = -EAGAIN;
 463                         goto out;
 464                 }
 465         }
 466
 467         for_each_cpu(i, cmd.mask) {
 468                 freqs.cpu = i;
 469                 cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
 470         }
 471         perf->state = next_perf_state;
 472
 473 out:
 474         return result;
 475 }
 476
 477 static int acpi_cpufreq_verify(struct cpufreq_policy *policy)
 478 {
 479         struct acpi_cpufreq_data *data = per_cpu(drv_data, policy->cpu);
 480
 481         dprintk("acpi_cpufreq_verify\n");
 482
 483         return cpufreq_frequency_table_verify(policy, data->freq_table);
 484 }
 485
 486 static unsigned long
 487 acpi_cpufreq_guess_freq(struct acpi_cpufreq_data *data, unsigned int cpu)
 488 {
 489         struct acpi_processor_performance *perf = data->acpi_data;
 490
 491         if (cpu_khz) {
 492                 /* search the closest match to cpu_khz */
 493                 unsigned int i;
 494                 unsigned long freq;
 495                 unsigned long freqn = perf->states[0].core_frequency * 1000;
 496
 497                 for (i=0; i<(perf->state_count-1); i++) {
 498                         freq = freqn;
 499                         freqn = perf->states[i+1].core_frequency * 1000;
 500                         if ((2 * cpu_khz) > (freqn + freq)) {
 501                                 perf->state = i;
 502                                 return freq;
 503                         }
 504                 }
 505                 perf->state = perf->state_count-1;
 506                 return freqn;
 507         } else {
 508                 /* assume CPU is at P0... */
 509                 perf->state = 0;
 510                 return perf->states[0].core_frequency * 1000;
 511         }
 512 }
 513
 514 static void free_acpi_perf_data(void)
 515 {
 516         unsigned int i;
 517
 518         /* Freeing a NULL pointer is OK, and alloc_percpu zeroes. */
 519         for_each_possible_cpu(i)
 520                 free_cpumask_var(per_cpu_ptr(acpi_perf_data, i)
 521                                  ->shared_cpu_map);
 522         free_percpu(acpi_perf_data);
 523 }
 524
 525 /*
 526  * acpi_cpufreq_early_init - initialize ACPI P-States library
 527  *
 528  * Initialize the ACPI P-States library (drivers/acpi/processor_perflib.c)
 529  * in order to determine correct frequency and voltage pairings. We can
 530  * do _PDC and _PSD and find out the processor dependency for the
 531  * actual init that will happen later...
 532  */
 533 static int __init acpi_cpufreq_early_init(void)
 534 {
 535         unsigned int i;
 536         dprintk("acpi_cpufreq_early_init\n");
 537
 538         acpi_perf_data = alloc_percpu(struct acpi_processor_performance);
 539         if (!acpi_perf_data) {
 540                 dprintk("Memory allocation error for acpi_perf_data.\n");
 541                 return -ENOMEM;
 542         }
 543         for_each_possible_cpu(i) {
 544                 if (!alloc_cpumask_var_node(
 545                         &per_cpu_ptr(acpi_perf_data, i)->shared_cpu_map,
 546                         GFP_KERNEL, cpu_to_node(i))) {
 547
 548                         /* Freeing a NULL pointer is OK: alloc_percpu zeroes. */
 549                         free_acpi_perf_data();
 550                         return -ENOMEM;
 551                 }
 552         }
 553
 554         /* Do initialization in ACPI core */
 555         acpi_processor_preregister_performance(acpi_perf_data);
 556         return 0;
 557 }
 558
 559 #ifdef CONFIG_SMP
 560 /*
 561  * Some BIOSes do SW_ANY coordination internally, either set it up in hw
 562  * or do it in BIOS firmware and won't inform about it to OS. If not
 563  * detected, this has a side effect of making CPU run at a different speed
 564  * than OS intended it to run at. Detect it and handle it cleanly.
 565  */
 566 static int bios_with_sw_any_bug;
 567
 568 static int sw_any_bug_found(const struct dmi_system_id *d)
 569 {
 570         bios_with_sw_any_bug = 1;
 571         return 0;
 572 }
 573
 574 static const struct dmi_system_id sw_any_bug_dmi_table[] = {
 575         {
 576                 .callback = sw_any_bug_found,
 577                 .ident = "Supermicro Server X6DLP",
 578                 .matches = {
 579                         DMI_MATCH(DMI_SYS_VENDOR, "Supermicro"),
 580                         DMI_MATCH(DMI_BIOS_VERSION, "080010"),
 581                         DMI_MATCH(DMI_PRODUCT_NAME, "X6DLP"),
 582                 },
 583         },
 584         { }
 585 };
 586 #endif
 587
 588 static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
 589 {
 590         unsigned int i;
 591         unsigned int valid_states = 0;
 592         unsigned int cpu = policy->cpu;
 593         struct acpi_cpufreq_data *data;
 594         unsigned int result = 0;
 595         struct cpuinfo_x86 *c = &cpu_data(policy->cpu);
 596         struct acpi_processor_performance *perf;
 597
 598         dprintk("acpi_cpufreq_cpu_init\n");
 599
 600         data = kzalloc(sizeof(struct acpi_cpufreq_data), GFP_KERNEL);
 601         if (!data)
 602                 return -ENOMEM;
 603
 604         data->acpi_data = per_cpu_ptr(acpi_perf_data, cpu);
 605         per_cpu(drv_data, cpu) = data;
 606
 607         if (cpu_has(c, X86_FEATURE_CONSTANT_TSC))
 608                 acpi_cpufreq_driver.flags |= CPUFREQ_CONST_LOOPS;
 609
 610         result = acpi_processor_register_performance(data->acpi_data, cpu);
 611         if (result)
 612                 goto err_free;
 613
 614         perf = data->acpi_data;
 615         policy->shared_type = perf->shared_type;
 616
 617         /*
 618          * Will let policy->cpus know about dependency only when software
 619          * coordination is required.
 620          */
 621         if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL ||
 622             policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {
 623                 cpumask_copy(policy->cpus, perf->shared_cpu_map);
 624         }
 625         cpumask_copy(policy->related_cpus, perf->shared_cpu_map);
 626
 627 #ifdef CONFIG_SMP
 628         dmi_check_system(sw_any_bug_dmi_table);
 629         if (bios_with_sw_any_bug && cpumask_weight(policy->cpus) == 1) {
 630                 policy->shared_type = CPUFREQ_SHARED_TYPE_ALL;
 631                 cpumask_copy(policy->cpus, cpu_core_mask(cpu));
 632         }
 633 #endif
 634
 635         /* capability check */
 636         if (perf->state_count <= 1) {
 637                 dprintk("No P-States\n");
 638                 result = -ENODEV;
 639                 goto err_unreg;
 640         }
 641
 642         if (perf->control_register.space_id != perf->status_register.space_id) {
 643                 result = -ENODEV;
 644                 goto err_unreg;
 645         }
 646
 647         switch (perf->control_register.space_id) {
 648         case ACPI_ADR_SPACE_SYSTEM_IO:
 649                 dprintk("SYSTEM IO addr space\n");
 650                 data->cpu_feature = SYSTEM_IO_CAPABLE;
 651                 break;
 652         case ACPI_ADR_SPACE_FIXED_HARDWARE:
 653                 dprintk("HARDWARE addr space\n");
 654                 if (!check_est_cpu(cpu)) {
 655                         result = -ENODEV;
 656                         goto err_unreg;
 657                 }
 658                 data->cpu_feature = SYSTEM_INTEL_MSR_CAPABLE;
 659                 break;
 660         default:
 661                 dprintk("Unknown addr space %d\n",
 662                         (u32) (perf->control_register.space_id));
 663                 result = -ENODEV;
 664                 goto err_unreg;
 665         }
 666
 667         data->freq_table = kmalloc(sizeof(struct cpufreq_frequency_table) *
 668                     (perf->state_count+1), GFP_KERNEL);
 669         if (!data->freq_table) {
 670                 result = -ENOMEM;
 671                 goto err_unreg;
 672         }
 673
 674         /* detect transition latency */
 675         policy->cpuinfo.transition_latency = 0;
 676         for (i=0; i<perf->state_count; i++) {
 677                 if ((perf->states[i].transition_latency * 1000) >
 678                     policy->cpuinfo.transition_latency)
 679                         policy->cpuinfo.transition_latency =
 680                             perf->states[i].transition_latency * 1000;
 681         }
 682
 683         data->max_freq = perf->states[0].core_frequency * 1000;
 684         /* table init */
 685         for (i=0; i<perf->state_count; i++) {
 686                 if (i>0 && perf->states[i].core_frequency >=
 687                     data->freq_table[valid_states-1].frequency / 1000)
 688                         continue;
 689
 690                 data->freq_table[valid_states].index = i;
 691                 data->freq_table[valid_states].frequency =
 692                     perf->states[i].core_frequency * 1000;
 693                 valid_states++;
 694         }
 695         data->freq_table[valid_states].frequency = CPUFREQ_TABLE_END;
 696         perf->state = 0;
 697
 698         result = cpufreq_frequency_table_cpuinfo(policy, data->freq_table);
 699         if (result)
 700                 goto err_freqfree;
 701
 702         switch (perf->control_register.space_id) {
 703         case ACPI_ADR_SPACE_SYSTEM_IO:
 704                 /* Current speed is unknown and not detectable by IO port */
 705                 policy->cur = acpi_cpufreq_guess_freq(data, policy->cpu);
 706                 break;
 707         case ACPI_ADR_SPACE_FIXED_HARDWARE:
 708                 acpi_cpufreq_driver.get = get_cur_freq_on_cpu;
 709                 policy->cur = get_cur_freq_on_cpu(cpu);
 710                 break;
 711         default:
 712                 break;
 713         }
 714
 715         /* notify BIOS that we exist */
 716         acpi_processor_notify_smm(THIS_MODULE);
 717
 718         /* Check for APERF/MPERF support in hardware */
 719         if (c->x86_vendor == X86_VENDOR_INTEL && c->cpuid_level >= 6) {
 720                 unsigned int ecx;
 721                 ecx = cpuid_ecx(6);
 722                 if (ecx & CPUID_6_ECX_APERFMPERF_CAPABILITY)
 723                         acpi_cpufreq_driver.getavg = get_measured_perf;
 724         }
 725
 726         dprintk("CPU%u - ACPI performance management activated.\n", cpu);
 727         for (i = 0; i < perf->state_count; i++)
 728                 dprintk("     %cP%d: %d MHz, %d mW, %d uS\n",
 729                         (i == perf->state ? '*' : ' '), i,
 730                         (u32) perf->states[i].core_frequency,
 731                         (u32) perf->states[i].power,
 732                         (u32) perf->states[i].transition_latency);
 733
 734         cpufreq_frequency_table_get_attr(data->freq_table, policy->cpu);
 735
 736         /*
 737          * the first call to ->target() should result in us actually
 738          * writing something to the appropriate registers.
 739          */
 740         data->resume = 1;
 741
 742         return result;
 743
 744 err_freqfree:
 745         kfree(data->freq_table);
 746 err_unreg:
 747         acpi_processor_unregister_performance(perf, cpu);
 748 err_free:
 749         kfree(data);
 750         per_cpu(drv_data, cpu) = NULL;
 751
 752         return result;
 753 }
 754
 755 static int acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy)
 756 {
 757         struct acpi_cpufreq_data *data = per_cpu(drv_data, policy->cpu);
 758
 759         dprintk("acpi_cpufreq_cpu_exit\n");
 760
 761         if (data) {
 762                 cpufreq_frequency_table_put_attr(policy->cpu);
 763                 per_cpu(drv_data, policy->cpu) = NULL;
 764                 acpi_processor_unregister_performance(data->acpi_data,
 765                                                       policy->cpu);
 766                 kfree(data);
 767         }
 768
 769         return 0;
 770 }
 771
 772 static int acpi_cpufreq_resume(struct cpufreq_policy *policy)
 773 {
 774         struct acpi_cpufreq_data *data = per_cpu(drv_data, policy->cpu);
 775
 776         dprintk("acpi_cpufreq_resume\n");
 777
 778         data->resume = 1;
 779
 780         return 0;
 781 }
 782
 783 static struct freq_attr *acpi_cpufreq_attr[] = {
 784         &cpufreq_freq_attr_scaling_available_freqs,
 785         NULL,
 786 };
 787
 788 static struct cpufreq_driver acpi_cpufreq_driver = {
 789         .verify = acpi_cpufreq_verify,
 790         .target = acpi_cpufreq_target,
 791         .init = acpi_cpufreq_cpu_init,
 792         .exit = acpi_cpufreq_cpu_exit,
 793         .resume = acpi_cpufreq_resume,
 794         .name = "acpi-cpufreq",
 795         .owner = THIS_MODULE,
 796         .attr = acpi_cpufreq_attr,
 797 };
 798
 799 static int __init acpi_cpufreq_init(void)
 800 {
 801         int ret;
 802
 803         if (acpi_disabled)
 804                 return 0;
 805
 806         dprintk("acpi_cpufreq_init\n");
 807
 808         ret = acpi_cpufreq_early_init();
 809         if (ret)
 810                 return ret;
 811
 812         ret = cpufreq_register_driver(&acpi_cpufreq_driver);
 813         if (ret)
 814                 free_acpi_perf_data();
 815
 816         return ret;
 817 }
 818
 819 static void __exit acpi_cpufreq_exit(void)
 820 {
 821         dprintk("acpi_cpufreq_exit\n");
 822
 823         cpufreq_unregister_driver(&acpi_cpufreq_driver);
 824
 825         free_percpu(acpi_perf_data);
 826 }
 827
 828 module_param(acpi_pstate_strict, uint, 0644);
 829 MODULE_PARM_DESC(acpi_pstate_strict,
 830         "value 0 or non-zero. non-zero -> strict ACPI checks are "
 831         "performed during frequency changes.");
 832
 833 late_initcall(acpi_cpufreq_init);
 834 module_exit(acpi_cpufreq_exit);
 835
 836 MODULE_ALIAS("acpi");