arch/i386/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/sched.h>        /* current */
  36 #include <linux/dmi.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 struct acpi_cpufreq_data *drv_data[NR_CPUS];
  72 static struct acpi_processor_performance *acpi_perf_data[NR_CPUS];
  73
  74 static struct cpufreq_driver acpi_cpufreq_driver;
  75
  76 static unsigned int acpi_pstate_strict;
  77
  78 static int check_est_cpu(unsigned int cpuid)
  79 {
  80         struct cpuinfo_x86 *cpu = &cpu_data[cpuid];
  81
  82         if (cpu->x86_vendor != X86_VENDOR_INTEL ||
  83             !cpu_has(cpu, X86_FEATURE_EST))
  84                 return 0;
  85
  86         return 1;
  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 static void wrport(u16 port, u8 bit_width, u32 value)
 131 {
 132         if (bit_width <= 8) {
 133                 outb(value, port);
 134         } else if (bit_width <= 16) {
 135                 outw(value, port);
 136         } else if (bit_width <= 32) {
 137                 outl(value, port);
 138         }
 139 }
 140
 141 static void rdport(u16 port, u8 bit_width, u32 * ret)
 142 {
 143         *ret = 0;
 144         if (bit_width <= 8) {
 145                 *ret = inb(port);
 146         } else if (bit_width <= 16) {
 147                 *ret = inw(port);
 148         } else if (bit_width <= 32) {
 149                 *ret = inl(port);
 150         }
 151 }
 152
 153 struct msr_addr {
 154         u32 reg;
 155 };
 156
 157 struct io_addr {
 158         u16 port;
 159         u8 bit_width;
 160 };
 161
 162 typedef union {
 163         struct msr_addr msr;
 164         struct io_addr io;
 165 } drv_addr_union;
 166
 167 struct drv_cmd {
 168         unsigned int type;
 169         cpumask_t mask;
 170         drv_addr_union addr;
 171         u32 val;
 172 };
 173
 174 static void do_drv_read(struct drv_cmd *cmd)
 175 {
 176         u32 h;
 177
 178         switch (cmd->type) {
 179         case SYSTEM_INTEL_MSR_CAPABLE:
 180                 rdmsr(cmd->addr.msr.reg, cmd->val, h);
 181                 break;
 182         case SYSTEM_IO_CAPABLE:
 183                 rdport(cmd->addr.io.port, cmd->addr.io.bit_width, &cmd->val);
 184                 break;
 185         default:
 186                 break;
 187         }
 188 }
 189
 190 static void do_drv_write(struct drv_cmd *cmd)
 191 {
 192         u32 h = 0;
 193
 194         switch (cmd->type) {
 195         case SYSTEM_INTEL_MSR_CAPABLE:
 196                 wrmsr(cmd->addr.msr.reg, cmd->val, h);
 197                 break;
 198         case SYSTEM_IO_CAPABLE:
 199                 wrport(cmd->addr.io.port, cmd->addr.io.bit_width, cmd->val);
 200                 break;
 201         default:
 202                 break;
 203         }
 204 }
 205
 206 static inline void drv_read(struct drv_cmd *cmd)
 207 {
 208         cpumask_t saved_mask = current->cpus_allowed;
 209         cmd->val = 0;
 210
 211         set_cpus_allowed(current, cmd->mask);
 212         do_drv_read(cmd);
 213         set_cpus_allowed(current, saved_mask);
 214
 215 }
 216
 217 static void drv_write(struct drv_cmd *cmd)
 218 {
 219         cpumask_t saved_mask = current->cpus_allowed;
 220         unsigned int i;
 221
 222         for_each_cpu_mask(i, cmd->mask) {
 223                 set_cpus_allowed(current, cpumask_of_cpu(i));
 224                 do_drv_write(cmd);
 225         }
 226
 227         set_cpus_allowed(current, saved_mask);
 228         return;
 229 }
 230
 231 static u32 get_cur_val(cpumask_t mask)
 232 {
 233         struct acpi_processor_performance *perf;
 234         struct drv_cmd cmd;
 235
 236         if (unlikely(cpus_empty(mask)))
 237                 return 0;
 238
 239         switch (drv_data[first_cpu(mask)]->cpu_feature) {
 240         case SYSTEM_INTEL_MSR_CAPABLE:
 241                 cmd.type = SYSTEM_INTEL_MSR_CAPABLE;
 242                 cmd.addr.msr.reg = MSR_IA32_PERF_STATUS;
 243                 break;
 244         case SYSTEM_IO_CAPABLE:
 245                 cmd.type = SYSTEM_IO_CAPABLE;
 246                 perf = drv_data[first_cpu(mask)]->acpi_data;
 247                 cmd.addr.io.port = perf->control_register.address;
 248                 cmd.addr.io.bit_width = perf->control_register.bit_width;
 249                 break;
 250         default:
 251                 return 0;
 252         }
 253
 254         cmd.mask = mask;
 255
 256         drv_read(&cmd);
 257
 258         dprintk("get_cur_val = %u\n", cmd.val);
 259
 260         return cmd.val;
 261 }
 262
 263 /*
 264  * Return the measured active (C0) frequency on this CPU since last call
 265  * to this function.
 266  * Input: cpu number
 267  * Return: Average CPU frequency in terms of max frequency (zero on error)
 268  *
 269  * We use IA32_MPERF and IA32_APERF MSRs to get the measured performance
 270  * over a period of time, while CPU is in C0 state.
 271  * IA32_MPERF counts at the rate of max advertised frequency
 272  * IA32_APERF counts at the rate of actual CPU frequency
 273  * Only IA32_APERF/IA32_MPERF ratio is architecturally defined and
 274  * no meaning should be associated with absolute values of these MSRs.
 275  */
 276 static unsigned int get_measured_perf(unsigned int cpu)
 277 {
 278         union {
 279                 struct {
 280                         u32 lo;
 281                         u32 hi;
 282                 } split;
 283                 u64 whole;
 284         } aperf_cur, mperf_cur;
 285
 286         cpumask_t saved_mask;
 287         unsigned int perf_percent;
 288         unsigned int retval;
 289
 290         saved_mask = current->cpus_allowed;
 291         set_cpus_allowed(current, cpumask_of_cpu(cpu));
 292         if (get_cpu() != cpu) {
 293                 /* We were not able to run on requested processor */
 294                 put_cpu();
 295                 return 0;
 296         }
 297
 298         rdmsr(MSR_IA32_APERF, aperf_cur.split.lo, aperf_cur.split.hi);
 299         rdmsr(MSR_IA32_MPERF, mperf_cur.split.lo, mperf_cur.split.hi);
 300
 301         wrmsr(MSR_IA32_APERF, 0,0);
 302         wrmsr(MSR_IA32_MPERF, 0,0);
 303
 304 #ifdef __i386__
 305         /*
 306          * We dont want to do 64 bit divide with 32 bit kernel
 307          * Get an approximate value. Return failure in case we cannot get
 308          * an approximate value.
 309          */
 310         if (unlikely(aperf_cur.split.hi || mperf_cur.split.hi)) {
 311                 int shift_count;
 312                 u32 h;
 313
 314                 h = max_t(u32, aperf_cur.split.hi, mperf_cur.split.hi);
 315                 shift_count = fls(h);
 316
 317                 aperf_cur.whole >>= shift_count;
 318                 mperf_cur.whole >>= shift_count;
 319         }
 320
 321         if (((unsigned long)(-1) / 100) < aperf_cur.split.lo) {
 322                 int shift_count = 7;
 323                 aperf_cur.split.lo >>= shift_count;
 324                 mperf_cur.split.lo >>= shift_count;
 325         }
 326
 327         if (aperf_cur.split.lo && mperf_cur.split.lo) {
 328                 perf_percent = (aperf_cur.split.lo * 100) / mperf_cur.split.lo;
 329         } else {
 330                 perf_percent = 0;
 331         }
 332
 333 #else
 334         if (unlikely(((unsigned long)(-1) / 100) < aperf_cur.whole)) {
 335                 int shift_count = 7;
 336                 aperf_cur.whole >>= shift_count;
 337                 mperf_cur.whole >>= shift_count;
 338         }
 339
 340         if (aperf_cur.whole && mperf_cur.whole) {
 341                 perf_percent = (aperf_cur.whole * 100) / mperf_cur.whole;
 342         } else {
 343                 perf_percent = 0;
 344         }
 345
 346 #endif
 347
 348         retval = drv_data[cpu]->max_freq * perf_percent / 100;
 349
 350         put_cpu();
 351         set_cpus_allowed(current, saved_mask);
 352
 353         dprintk("cpu %d: performance percent %d\n", cpu, perf_percent);
 354         return retval;
 355 }
 356
 357 static unsigned int get_cur_freq_on_cpu(unsigned int cpu)
 358 {
 359         struct acpi_cpufreq_data *data = drv_data[cpu];
 360         unsigned int freq;
 361
 362         dprintk("get_cur_freq_on_cpu (%d)\n", cpu);
 363
 364         if (unlikely(data == NULL ||
 365                      data->acpi_data == NULL || data->freq_table == NULL)) {
 366                 return 0;
 367         }
 368
 369         freq = extract_freq(get_cur_val(cpumask_of_cpu(cpu)), data);
 370         dprintk("cur freq = %u\n", freq);
 371
 372         return freq;
 373 }
 374
 375 static unsigned int check_freqs(cpumask_t mask, unsigned int freq,
 376                                 struct acpi_cpufreq_data *data)
 377 {
 378         unsigned int cur_freq;
 379         unsigned int i;
 380
 381         for (i = 0; i < 100; i++) {
 382                 cur_freq = extract_freq(get_cur_val(mask), data);
 383                 if (cur_freq == freq)
 384                         return 1;
 385                 udelay(10);
 386         }
 387         return 0;
 388 }
 389
 390 static int acpi_cpufreq_target(struct cpufreq_policy *policy,
 391                                unsigned int target_freq, unsigned int relation)
 392 {
 393         struct acpi_cpufreq_data *data = drv_data[policy->cpu];
 394         struct acpi_processor_performance *perf;
 395         struct cpufreq_freqs freqs;
 396         cpumask_t online_policy_cpus;
 397         struct drv_cmd cmd;
 398         unsigned int msr;
 399         unsigned int next_state = 0;
 400         unsigned int next_perf_state = 0;
 401         unsigned int i;
 402         int result = 0;
 403
 404         dprintk("acpi_cpufreq_target %d (%d)\n", target_freq, policy->cpu);
 405
 406         if (unlikely(data == NULL ||
 407                      data->acpi_data == NULL || data->freq_table == NULL)) {
 408                 return -ENODEV;
 409         }
 410
 411         perf = data->acpi_data;
 412         result = cpufreq_frequency_table_target(policy,
 413                                                 data->freq_table,
 414                                                 target_freq,
 415                                                 relation, &next_state);
 416         if (unlikely(result))
 417                 return -ENODEV;
 418
 419 #ifdef CONFIG_HOTPLUG_CPU
 420         /* cpufreq holds the hotplug lock, so we are safe from here on */
 421         cpus_and(online_policy_cpus, cpu_online_map, policy->cpus);
 422 #else
 423         online_policy_cpus = policy->cpus;
 424 #endif
 425
 426         next_perf_state = data->freq_table[next_state].index;
 427         if (perf->state == next_perf_state) {
 428                 if (unlikely(data->resume)) {
 429                         dprintk("Called after resume, resetting to P%d\n",
 430                                 next_perf_state);
 431                         data->resume = 0;
 432                 } else {
 433                         dprintk("Already at target state (P%d)\n",
 434                                 next_perf_state);
 435                         return 0;
 436                 }
 437         }
 438
 439         switch (data->cpu_feature) {
 440         case SYSTEM_INTEL_MSR_CAPABLE:
 441                 cmd.type = SYSTEM_INTEL_MSR_CAPABLE;
 442                 cmd.addr.msr.reg = MSR_IA32_PERF_CTL;
 443                 msr =
 444                     (u32) perf->states[next_perf_state].
 445                     control & INTEL_MSR_RANGE;
 446                 cmd.val = (cmd.val & ~INTEL_MSR_RANGE) | msr;
 447                 break;
 448         case SYSTEM_IO_CAPABLE:
 449                 cmd.type = SYSTEM_IO_CAPABLE;
 450                 cmd.addr.io.port = perf->control_register.address;
 451                 cmd.addr.io.bit_width = perf->control_register.bit_width;
 452                 cmd.val = (u32) perf->states[next_perf_state].control;
 453                 break;
 454         default:
 455                 return -ENODEV;
 456         }
 457
 458         cpus_clear(cmd.mask);
 459
 460         if (policy->shared_type != CPUFREQ_SHARED_TYPE_ANY)
 461                 cmd.mask = online_policy_cpus;
 462         else
 463                 cpu_set(policy->cpu, cmd.mask);
 464
 465         freqs.old = data->freq_table[perf->state].frequency;
 466         freqs.new = data->freq_table[next_perf_state].frequency;
 467         for_each_cpu_mask(i, cmd.mask) {
 468                 freqs.cpu = i;
 469                 cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
 470         }
 471
 472         drv_write(&cmd);
 473
 474         if (acpi_pstate_strict) {
 475                 if (!check_freqs(cmd.mask, freqs.new, data)) {
 476                         dprintk("acpi_cpufreq_target failed (%d)\n",
 477                                 policy->cpu);
 478                         return -EAGAIN;
 479                 }
 480         }
 481
 482         for_each_cpu_mask(i, cmd.mask) {
 483                 freqs.cpu = i;
 484                 cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
 485         }
 486         perf->state = next_perf_state;
 487
 488         return result;
 489 }
 490
 491 static int acpi_cpufreq_verify(struct cpufreq_policy *policy)
 492 {
 493         struct acpi_cpufreq_data *data = drv_data[policy->cpu];
 494
 495         dprintk("acpi_cpufreq_verify\n");
 496
 497         return cpufreq_frequency_table_verify(policy, data->freq_table);
 498 }
 499
 500 static unsigned long
 501 acpi_cpufreq_guess_freq(struct acpi_cpufreq_data *data, unsigned int cpu)
 502 {
 503         struct acpi_processor_performance *perf = data->acpi_data;
 504
 505         if (cpu_khz) {
 506                 /* search the closest match to cpu_khz */
 507                 unsigned int i;
 508                 unsigned long freq;
 509                 unsigned long freqn = perf->states[0].core_frequency * 1000;
 510
 511                 for (i = 0; i < (perf->state_count - 1); i++) {
 512                         freq = freqn;
 513                         freqn = perf->states[i + 1].core_frequency * 1000;
 514                         if ((2 * cpu_khz) > (freqn + freq)) {
 515                                 perf->state = i;
 516                                 return freq;
 517                         }
 518                 }
 519                 perf->state = perf->state_count - 1;
 520                 return freqn;
 521         } else {
 522                 /* assume CPU is at P0... */
 523                 perf->state = 0;
 524                 return perf->states[0].core_frequency * 1000;
 525         }
 526 }
 527
 528 /*
 529  * acpi_cpufreq_early_init - initialize ACPI P-States library
 530  *
 531  * Initialize the ACPI P-States library (drivers/acpi/processor_perflib.c)
 532  * in order to determine correct frequency and voltage pairings. We can
 533  * do _PDC and _PSD and find out the processor dependency for the
 534  * actual init that will happen later...
 535  */
 536 static int acpi_cpufreq_early_init(void)
 537 {
 538         struct acpi_processor_performance *data;
 539         cpumask_t covered;
 540         unsigned int i, j;
 541
 542         dprintk("acpi_cpufreq_early_init\n");
 543
 544         for_each_possible_cpu(i) {
 545                 data = kzalloc(sizeof(struct acpi_processor_performance),
 546                                GFP_KERNEL);
 547                 if (!data) {
 548                         for_each_cpu_mask(j, covered) {
 549                                 kfree(acpi_perf_data[j]);
 550                                 acpi_perf_data[j] = NULL;
 551                         }
 552                         return -ENOMEM;
 553                 }
 554                 acpi_perf_data[i] = data;
 555                 cpu_set(i, covered);
 556         }
 557
 558         /* Do initialization in ACPI core */
 559         acpi_processor_preregister_performance(acpi_perf_data);
 560         return 0;
 561 }
 562
 563 /*
 564  * Some BIOSes do SW_ANY coordination internally, either set it up in hw
 565  * or do it in BIOS firmware and won't inform about it to OS. If not
 566  * detected, this has a side effect of making CPU run at a different speed
 567  * than OS intended it to run at. Detect it and handle it cleanly.
 568  */
 569 static int bios_with_sw_any_bug;
 570
 571 static int sw_any_bug_found(struct dmi_system_id *d)
 572 {
 573         bios_with_sw_any_bug = 1;
 574         return 0;
 575 }
 576
 577 static struct dmi_system_id sw_any_bug_dmi_table[] = {
 578         {
 579                 .callback = sw_any_bug_found,
 580                 .ident = "Supermicro Server X6DLP",
 581                 .matches = {
 582                         DMI_MATCH(DMI_SYS_VENDOR, "Supermicro"),
 583                         DMI_MATCH(DMI_BIOS_VERSION, "080010"),
 584                         DMI_MATCH(DMI_PRODUCT_NAME, "X6DLP"),
 585                 },
 586         },
 587         { }
 588 };
 589
 590 static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
 591 {
 592         unsigned int i;
 593         unsigned int valid_states = 0;
 594         unsigned int cpu = policy->cpu;
 595         struct acpi_cpufreq_data *data;
 596         unsigned int result = 0;
 597         struct cpuinfo_x86 *c = &cpu_data[policy->cpu];
 598         struct acpi_processor_performance *perf;
 599
 600         dprintk("acpi_cpufreq_cpu_init\n");
 601
 602         if (!acpi_perf_data[cpu])
 603                 return -ENODEV;
 604
 605         data = kzalloc(sizeof(struct acpi_cpufreq_data), GFP_KERNEL);
 606         if (!data)
 607                 return -ENOMEM;
 608
 609         data->acpi_data = acpi_perf_data[cpu];
 610         drv_data[cpu] = data;
 611
 612         if (cpu_has(c, X86_FEATURE_CONSTANT_TSC)) {
 613                 acpi_cpufreq_driver.flags |= CPUFREQ_CONST_LOOPS;
 614         }
 615
 616         result = acpi_processor_register_performance(data->acpi_data, cpu);
 617         if (result)
 618                 goto err_free;
 619
 620         perf = data->acpi_data;
 621         policy->shared_type = perf->shared_type;
 622         /*
 623          * Will let policy->cpus know about dependency only when software
 624          * coordination is required.
 625          */
 626         if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL ||
 627             policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {
 628                 policy->cpus = perf->shared_cpu_map;
 629         }
 630
 631 #ifdef CONFIG_SMP
 632         dmi_check_system(sw_any_bug_dmi_table);
 633         if (bios_with_sw_any_bug && cpus_weight(policy->cpus) == 1) {
 634                 policy->shared_type = CPUFREQ_SHARED_TYPE_ALL;
 635                 policy->cpus = cpu_core_map[cpu];
 636         }
 637 #endif
 638
 639         /* capability check */
 640         if (perf->state_count <= 1) {
 641                 dprintk("No P-States\n");
 642                 result = -ENODEV;
 643                 goto err_unreg;
 644         }
 645
 646         if (perf->control_register.space_id != perf->status_register.space_id) {
 647                 result = -ENODEV;
 648                 goto err_unreg;
 649         }
 650
 651         switch (perf->control_register.space_id) {
 652         case ACPI_ADR_SPACE_SYSTEM_IO:
 653                 dprintk("SYSTEM IO addr space\n");
 654                 data->cpu_feature = SYSTEM_IO_CAPABLE;
 655                 break;
 656         case ACPI_ADR_SPACE_FIXED_HARDWARE:
 657                 dprintk("HARDWARE addr space\n");
 658                 if (!check_est_cpu(cpu)) {
 659                         result = -ENODEV;
 660                         goto err_unreg;
 661                 }
 662                 data->cpu_feature = SYSTEM_INTEL_MSR_CAPABLE;
 663                 break;
 664         default:
 665                 dprintk("Unknown addr space %d\n",
 666                         (u32) (perf->control_register.space_id));
 667                 result = -ENODEV;
 668                 goto err_unreg;
 669         }
 670
 671         data->freq_table =
 672             kmalloc(sizeof(struct cpufreq_frequency_table) *
 673                     (perf->state_count + 1), GFP_KERNEL);
 674         if (!data->freq_table) {
 675                 result = -ENOMEM;
 676                 goto err_unreg;
 677         }
 678
 679         /* detect transition latency */
 680         policy->cpuinfo.transition_latency = 0;
 681         for (i = 0; i < perf->state_count; i++) {
 682                 if ((perf->states[i].transition_latency * 1000) >
 683                     policy->cpuinfo.transition_latency)
 684                         policy->cpuinfo.transition_latency =
 685                             perf->states[i].transition_latency * 1000;
 686         }
 687         policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 688
 689         data->max_freq = perf->states[0].core_frequency * 1000;
 690         /* table init */
 691         for (i = 0; i < perf->state_count; i++) {
 692                 if (i > 0 && perf->states[i].core_frequency ==
 693                     perf->states[i - 1].core_frequency)
 694                         continue;
 695
 696                 data->freq_table[valid_states].index = i;
 697                 data->freq_table[valid_states].frequency =
 698                     perf->states[i].core_frequency * 1000;
 699                 valid_states++;
 700         }
 701         data->freq_table[perf->state_count].frequency = CPUFREQ_TABLE_END;
 702
 703         result = cpufreq_frequency_table_cpuinfo(policy, data->freq_table);
 704         if (result) {
 705                 goto err_freqfree;
 706         }
 707
 708         switch (data->cpu_feature) {
 709         case ACPI_ADR_SPACE_SYSTEM_IO:
 710                 /* Current speed is unknown and not detectable by IO port */
 711                 policy->cur = acpi_cpufreq_guess_freq(data, policy->cpu);
 712                 break;
 713         case ACPI_ADR_SPACE_FIXED_HARDWARE:
 714                 acpi_cpufreq_driver.get = get_cur_freq_on_cpu;
 715                 get_cur_freq_on_cpu(cpu);
 716                 break;
 717         default:
 718                 break;
 719         }
 720
 721         /* notify BIOS that we exist */
 722         acpi_processor_notify_smm(THIS_MODULE);
 723
 724         /* Check for APERF/MPERF support in hardware */
 725         if (c->x86_vendor == X86_VENDOR_INTEL && c->cpuid_level >= 6) {
 726                 unsigned int ecx;
 727                 ecx = cpuid_ecx(6);
 728                 if (ecx & CPUID_6_ECX_APERFMPERF_CAPABILITY) {
 729                         acpi_cpufreq_driver.getavg = get_measured_perf;
 730                 }
 731         }
 732
 733         dprintk("CPU%u - ACPI performance management activated.\n", cpu);
 734         for (i = 0; i < perf->state_count; i++)
 735                 dprintk("     %cP%d: %d MHz, %d mW, %d uS\n",
 736                         (i == perf->state ? '*' : ' '), i,
 737                         (u32) perf->states[i].core_frequency,
 738                         (u32) perf->states[i].power,
 739                         (u32) perf->states[i].transition_latency);
 740
 741         cpufreq_frequency_table_get_attr(data->freq_table, policy->cpu);
 742
 743         /*
 744          * the first call to ->target() should result in us actually
 745          * writing something to the appropriate registers.
 746          */
 747         data->resume = 1;
 748
 749         return result;
 750
 751       err_freqfree:
 752         kfree(data->freq_table);
 753       err_unreg:
 754         acpi_processor_unregister_performance(perf, cpu);
 755       err_free:
 756         kfree(data);
 757         drv_data[cpu] = NULL;
 758
 759         return result;
 760 }
 761
 762 static int acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy)
 763 {
 764         struct acpi_cpufreq_data *data = drv_data[policy->cpu];
 765
 766         dprintk("acpi_cpufreq_cpu_exit\n");
 767
 768         if (data) {
 769                 cpufreq_frequency_table_put_attr(policy->cpu);
 770                 drv_data[policy->cpu] = NULL;
 771                 acpi_processor_unregister_performance(data->acpi_data,
 772                                                       policy->cpu);
 773                 kfree(data);
 774         }
 775
 776         return 0;
 777 }
 778
 779 static int acpi_cpufreq_resume(struct cpufreq_policy *policy)
 780 {
 781         struct acpi_cpufreq_data *data = drv_data[policy->cpu];
 782
 783         dprintk("acpi_cpufreq_resume\n");
 784
 785         data->resume = 1;
 786
 787         return 0;
 788 }
 789
 790 static struct freq_attr *acpi_cpufreq_attr[] = {
 791         &cpufreq_freq_attr_scaling_available_freqs,
 792         NULL,
 793 };
 794
 795 static struct cpufreq_driver acpi_cpufreq_driver = {
 796         .verify = acpi_cpufreq_verify,
 797         .target = acpi_cpufreq_target,
 798         .init = acpi_cpufreq_cpu_init,
 799         .exit = acpi_cpufreq_cpu_exit,
 800         .resume = acpi_cpufreq_resume,
 801         .name = "acpi-cpufreq",
 802         .owner = THIS_MODULE,
 803         .attr = acpi_cpufreq_attr,
 804 };
 805
 806 static int __init acpi_cpufreq_init(void)
 807 {
 808         dprintk("acpi_cpufreq_init\n");
 809
 810         acpi_cpufreq_early_init();
 811
 812         return cpufreq_register_driver(&acpi_cpufreq_driver);
 813 }
 814
 815 static void __exit acpi_cpufreq_exit(void)
 816 {
 817         unsigned int i;
 818         dprintk("acpi_cpufreq_exit\n");
 819
 820         cpufreq_unregister_driver(&acpi_cpufreq_driver);
 821
 822         for_each_possible_cpu(i) {
 823                 kfree(acpi_perf_data[i]);
 824                 acpi_perf_data[i] = NULL;
 825         }
 826         return;
 827 }
 828
 829 module_param(acpi_pstate_strict, uint, 0644);
 830 MODULE_PARM_DESC(acpi_pstate_strict,
 831                  "value 0 or non-zero. non-zero -> strict ACPI checks are performed during frequency changes.");
 832
 833 late_initcall(acpi_cpufreq_init);
 834 module_exit(acpi_cpufreq_exit);
 835
 836 MODULE_ALIAS("acpi");