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_var_t 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         if (unlikely(!alloc_cpumask_var(&cmd.mask, GFP_KERNEL)))
 235                 return 0;
 236
 237         cpumask_copy(cmd.mask, mask);
 238
 239         drv_read(&cmd);
 240
 241         free_cpumask_var(cmd.mask);
 242
 243         dprintk("get_cur_val = %u\n", cmd.val);
 244
 245         return cmd.val;
 246 }
 247
 248 struct perf_cur {
 249         union {
 250                 struct {
 251                         u32 lo;
 252                         u32 hi;
 253                 } split;
 254                 u64 whole;
 255         } aperf_cur, mperf_cur;
 256 };
 257
 258
 259 static long read_measured_perf_ctrs(void *_cur)
 260 {
 261         struct perf_cur *cur = _cur;
 262
 263         rdmsr(MSR_IA32_APERF, cur->aperf_cur.split.lo, cur->aperf_cur.split.hi);
 264         rdmsr(MSR_IA32_MPERF, cur->mperf_cur.split.lo, cur->mperf_cur.split.hi);
 265
 266         wrmsr(MSR_IA32_APERF, 0, 0);
 267         wrmsr(MSR_IA32_MPERF, 0, 0);
 268
 269         return 0;
 270 }
 271
 272 /*
 273  * Return the measured active (C0) frequency on this CPU since last call
 274  * to this function.
 275  * Input: cpu number
 276  * Return: Average CPU frequency in terms of max frequency (zero on error)
 277  *
 278  * We use IA32_MPERF and IA32_APERF MSRs to get the measured performance
 279  * over a period of time, while CPU is in C0 state.
 280  * IA32_MPERF counts at the rate of max advertised frequency
 281  * IA32_APERF counts at the rate of actual CPU frequency
 282  * Only IA32_APERF/IA32_MPERF ratio is architecturally defined and
 283  * no meaning should be associated with absolute values of these MSRs.
 284  */
 285 static unsigned int get_measured_perf(struct cpufreq_policy *policy,
 286                                       unsigned int cpu)
 287 {
 288         struct perf_cur cur;
 289         unsigned int perf_percent;
 290         unsigned int retval;
 291
 292         if (!work_on_cpu(cpu, read_measured_perf_ctrs, &cur))
 293                 return 0;
 294
 295 #ifdef __i386__
 296         /*
 297          * We dont want to do 64 bit divide with 32 bit kernel
 298          * Get an approximate value. Return failure in case we cannot get
 299          * an approximate value.
 300          */
 301         if (unlikely(cur.aperf_cur.split.hi || cur.mperf_cur.split.hi)) {
 302                 int shift_count;
 303                 u32 h;
 304
 305                 h = max_t(u32, cur.aperf_cur.split.hi, cur.mperf_cur.split.hi);
 306                 shift_count = fls(h);
 307
 308                 cur.aperf_cur.whole >>= shift_count;
 309                 cur.mperf_cur.whole >>= shift_count;
 310         }
 311
 312         if (((unsigned long)(-1) / 100) < cur.aperf_cur.split.lo) {
 313                 int shift_count = 7;
 314                 cur.aperf_cur.split.lo >>= shift_count;
 315                 cur.mperf_cur.split.lo >>= shift_count;
 316         }
 317
 318         if (cur.aperf_cur.split.lo && cur.mperf_cur.split.lo)
 319                 perf_percent = (cur.aperf_cur.split.lo * 100) /
 320                                 cur.mperf_cur.split.lo;
 321         else
 322                 perf_percent = 0;
 323
 324 #else
 325         if (unlikely(((unsigned long)(-1) / 100) < cur.aperf_cur.whole)) {
 326                 int shift_count = 7;
 327                 cur.aperf_cur.whole >>= shift_count;
 328                 cur.mperf_cur.whole >>= shift_count;
 329         }
 330
 331         if (cur.aperf_cur.whole && cur.mperf_cur.whole)
 332                 perf_percent = (cur.aperf_cur.whole * 100) /
 333                                 cur.mperf_cur.whole;
 334         else
 335                 perf_percent = 0;
 336
 337 #endif
 338
 339         retval = per_cpu(drv_data, policy->cpu)->max_freq * perf_percent / 100;
 340
 341         return retval;
 342 }
 343
 344 static unsigned int get_cur_freq_on_cpu(unsigned int cpu)
 345 {
 346         struct acpi_cpufreq_data *data = per_cpu(drv_data, cpu);
 347         unsigned int freq;
 348         unsigned int cached_freq;
 349
 350         dprintk("get_cur_freq_on_cpu (%d)\n", cpu);
 351
 352         if (unlikely(data == NULL ||
 353                      data->acpi_data == NULL || data->freq_table == NULL)) {
 354                 return 0;
 355         }
 356
 357         cached_freq = data->freq_table[data->acpi_data->state].frequency;
 358         freq = extract_freq(get_cur_val(cpumask_of(cpu)), data);
 359         if (freq != cached_freq) {
 360                 /*
 361                  * The dreaded BIOS frequency change behind our back.
 362                  * Force set the frequency on next target call.
 363                  */
 364                 data->resume = 1;
 365         }
 366
 367         dprintk("cur freq = %u\n", freq);
 368
 369         return freq;
 370 }
 371
 372 static unsigned int check_freqs(const cpumask_t *mask, unsigned int freq,
 373                                 struct acpi_cpufreq_data *data)
 374 {
 375         unsigned int cur_freq;
 376         unsigned int i;
 377
 378         for (i=0; i<100; i++) {
 379                 cur_freq = extract_freq(get_cur_val(mask), data);
 380                 if (cur_freq == freq)
 381                         return 1;
 382                 udelay(10);
 383         }
 384         return 0;
 385 }
 386
 387 static int acpi_cpufreq_target(struct cpufreq_policy *policy,
 388                                unsigned int target_freq, unsigned int relation)
 389 {
 390         struct acpi_cpufreq_data *data = per_cpu(drv_data, policy->cpu);
 391         struct acpi_processor_performance *perf;
 392         struct cpufreq_freqs freqs;
 393         struct drv_cmd cmd;
 394         unsigned int next_state = 0; /* Index into freq_table */
 395         unsigned int next_perf_state = 0; /* Index into perf table */
 396         unsigned int i;
 397         int result = 0;
 398         struct power_trace it;
 399
 400         dprintk("acpi_cpufreq_target %d (%d)\n", target_freq, policy->cpu);
 401
 402         if (unlikely(data == NULL ||
 403              data->acpi_data == NULL || data->freq_table == NULL)) {
 404                 return -ENODEV;
 405         }
 406
 407         if (unlikely(!alloc_cpumask_var(&cmd.mask, GFP_KERNEL)))
 408                 return -ENOMEM;
 409
 410         perf = data->acpi_data;
 411         result = cpufreq_frequency_table_target(policy,
 412                                                 data->freq_table,
 413                                                 target_freq,
 414                                                 relation, &next_state);
 415         if (unlikely(result)) {
 416                 result = -ENODEV;
 417                 goto out;
 418         }
 419
 420         next_perf_state = data->freq_table[next_state].index;
 421         if (perf->state == next_perf_state) {
 422                 if (unlikely(data->resume)) {
 423                         dprintk("Called after resume, resetting to P%d\n",
 424                                 next_perf_state);
 425                         data->resume = 0;
 426                 } else {
 427                         dprintk("Already at target state (P%d)\n",
 428                                 next_perf_state);
 429                         goto out;
 430                 }
 431         }
 432
 433         trace_power_mark(&it, POWER_PSTATE, next_perf_state);
 434
 435         switch (data->cpu_feature) {
 436         case SYSTEM_INTEL_MSR_CAPABLE:
 437                 cmd.type = SYSTEM_INTEL_MSR_CAPABLE;
 438                 cmd.addr.msr.reg = MSR_IA32_PERF_CTL;
 439                 cmd.val = (u32) perf->states[next_perf_state].control;
 440                 break;
 441         case SYSTEM_IO_CAPABLE:
 442                 cmd.type = SYSTEM_IO_CAPABLE;
 443                 cmd.addr.io.port = perf->control_register.address;
 444                 cmd.addr.io.bit_width = perf->control_register.bit_width;
 445                 cmd.val = (u32) perf->states[next_perf_state].control;
 446                 break;
 447         default:
 448                 result = -ENODEV;
 449                 goto out;
 450         }
 451
 452         /* cpufreq holds the hotplug lock, so we are safe from here on */
 453         if (policy->shared_type != CPUFREQ_SHARED_TYPE_ANY)
 454                 cpumask_and(cmd.mask, cpu_online_mask, policy->cpus);
 455         else
 456                 cpumask_copy(cmd.mask, cpumask_of(policy->cpu));
 457
 458         freqs.old = perf->states[perf->state].core_frequency * 1000;
 459         freqs.new = data->freq_table[next_state].frequency;
 460         for_each_cpu(i, cmd.mask) {
 461                 freqs.cpu = i;
 462                 cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
 463         }
 464
 465         drv_write(&cmd);
 466
 467         if (acpi_pstate_strict) {
 468                 if (!check_freqs(cmd.mask, freqs.new, data)) {
 469                         dprintk("acpi_cpufreq_target failed (%d)\n",
 470                                 policy->cpu);
 471                         result = -EAGAIN;
 472                         goto out;
 473                 }
 474         }
 475
 476         for_each_cpu(i, cmd.mask) {
 477                 freqs.cpu = i;
 478                 cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
 479         }
 480         perf->state = next_perf_state;
 481
 482 out:
 483         free_cpumask_var(cmd.mask);
 484         return result;
 485 }
 486
 487 static int acpi_cpufreq_verify(struct cpufreq_policy *policy)
 488 {
 489         struct acpi_cpufreq_data *data = per_cpu(drv_data, policy->cpu);
 490
 491         dprintk("acpi_cpufreq_verify\n");
 492
 493         return cpufreq_frequency_table_verify(policy, data->freq_table);
 494 }
 495
 496 static unsigned long
 497 acpi_cpufreq_guess_freq(struct acpi_cpufreq_data *data, unsigned int cpu)
 498 {
 499         struct acpi_processor_performance *perf = data->acpi_data;
 500
 501         if (cpu_khz) {
 502                 /* search the closest match to cpu_khz */
 503                 unsigned int i;
 504                 unsigned long freq;
 505                 unsigned long freqn = perf->states[0].core_frequency * 1000;
 506
 507                 for (i=0; i<(perf->state_count-1); i++) {
 508                         freq = freqn;
 509                         freqn = perf->states[i+1].core_frequency * 1000;
 510                         if ((2 * cpu_khz) > (freqn + freq)) {
 511                                 perf->state = i;
 512                                 return freq;
 513                         }
 514                 }
 515                 perf->state = perf->state_count-1;
 516                 return freqn;
 517         } else {
 518                 /* assume CPU is at P0... */
 519                 perf->state = 0;
 520                 return perf->states[0].core_frequency * 1000;
 521         }
 522 }
 523
 524 static void free_acpi_perf_data(void)
 525 {
 526         unsigned int i;
 527
 528         /* Freeing a NULL pointer is OK, and alloc_percpu zeroes. */
 529         for_each_possible_cpu(i)
 530                 free_cpumask_var(per_cpu_ptr(acpi_perf_data, i)
 531                                  ->shared_cpu_map);
 532         free_percpu(acpi_perf_data);
 533 }
 534
 535 /*
 536  * acpi_cpufreq_early_init - initialize ACPI P-States library
 537  *
 538  * Initialize the ACPI P-States library (drivers/acpi/processor_perflib.c)
 539  * in order to determine correct frequency and voltage pairings. We can
 540  * do _PDC and _PSD and find out the processor dependency for the
 541  * actual init that will happen later...
 542  */
 543 static int __init acpi_cpufreq_early_init(void)
 544 {
 545         unsigned int i;
 546         dprintk("acpi_cpufreq_early_init\n");
 547
 548         acpi_perf_data = alloc_percpu(struct acpi_processor_performance);
 549         if (!acpi_perf_data) {
 550                 dprintk("Memory allocation error for acpi_perf_data.\n");
 551                 return -ENOMEM;
 552         }
 553         for_each_possible_cpu(i) {
 554                 if (!alloc_cpumask_var_node(
 555                         &per_cpu_ptr(acpi_perf_data, i)->shared_cpu_map,
 556                         GFP_KERNEL, cpu_to_node(i))) {
 557
 558                         /* Freeing a NULL pointer is OK: alloc_percpu zeroes. */
 559                         free_acpi_perf_data();
 560                         return -ENOMEM;
 561                 }
 562         }
 563
 564         /* Do initialization in ACPI core */
 565         acpi_processor_preregister_performance(acpi_perf_data);
 566         return 0;
 567 }
 568
 569 #ifdef CONFIG_SMP
 570 /*
 571  * Some BIOSes do SW_ANY coordination internally, either set it up in hw
 572  * or do it in BIOS firmware and won't inform about it to OS. If not
 573  * detected, this has a side effect of making CPU run at a different speed
 574  * than OS intended it to run at. Detect it and handle it cleanly.
 575  */
 576 static int bios_with_sw_any_bug;
 577
 578 static int sw_any_bug_found(const struct dmi_system_id *d)
 579 {
 580         bios_with_sw_any_bug = 1;
 581         return 0;
 582 }
 583
 584 static const struct dmi_system_id sw_any_bug_dmi_table[] = {
 585         {
 586                 .callback = sw_any_bug_found,
 587                 .ident = "Supermicro Server X6DLP",
 588                 .matches = {
 589                         DMI_MATCH(DMI_SYS_VENDOR, "Supermicro"),
 590                         DMI_MATCH(DMI_BIOS_VERSION, "080010"),
 591                         DMI_MATCH(DMI_PRODUCT_NAME, "X6DLP"),
 592                 },
 593         },
 594         { }
 595 };
 596 #endif
 597
 598 static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
 599 {
 600         unsigned int i;
 601         unsigned int valid_states = 0;
 602         unsigned int cpu = policy->cpu;
 603         struct acpi_cpufreq_data *data;
 604         unsigned int result = 0;
 605         struct cpuinfo_x86 *c = &cpu_data(policy->cpu);
 606         struct acpi_processor_performance *perf;
 607
 608         dprintk("acpi_cpufreq_cpu_init\n");
 609
 610         data = kzalloc(sizeof(struct acpi_cpufreq_data), GFP_KERNEL);
 611         if (!data)
 612                 return -ENOMEM;
 613
 614         data->acpi_data = percpu_ptr(acpi_perf_data, cpu);
 615         per_cpu(drv_data, cpu) = data;
 616
 617         if (cpu_has(c, X86_FEATURE_CONSTANT_TSC))
 618                 acpi_cpufreq_driver.flags |= CPUFREQ_CONST_LOOPS;
 619
 620         result = acpi_processor_register_performance(data->acpi_data, cpu);
 621         if (result)
 622                 goto err_free;
 623
 624         perf = data->acpi_data;
 625         policy->shared_type = perf->shared_type;
 626
 627         /*
 628          * Will let policy->cpus know about dependency only when software
 629          * coordination is required.
 630          */
 631         if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL ||
 632             policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {
 633                 cpumask_copy(policy->cpus, perf->shared_cpu_map);
 634         }
 635         cpumask_copy(policy->related_cpus, perf->shared_cpu_map);
 636
 637 #ifdef CONFIG_SMP
 638         dmi_check_system(sw_any_bug_dmi_table);
 639         if (bios_with_sw_any_bug && cpumask_weight(policy->cpus) == 1) {
 640                 policy->shared_type = CPUFREQ_SHARED_TYPE_ALL;
 641                 cpumask_copy(policy->cpus, cpu_core_mask(cpu));
 642         }
 643 #endif
 644
 645         /* capability check */
 646         if (perf->state_count <= 1) {
 647                 dprintk("No P-States\n");
 648                 result = -ENODEV;
 649                 goto err_unreg;
 650         }
 651
 652         if (perf->control_register.space_id != perf->status_register.space_id) {
 653                 result = -ENODEV;
 654                 goto err_unreg;
 655         }
 656
 657         switch (perf->control_register.space_id) {
 658         case ACPI_ADR_SPACE_SYSTEM_IO:
 659                 dprintk("SYSTEM IO addr space\n");
 660                 data->cpu_feature = SYSTEM_IO_CAPABLE;
 661                 break;
 662         case ACPI_ADR_SPACE_FIXED_HARDWARE:
 663                 dprintk("HARDWARE addr space\n");
 664                 if (!check_est_cpu(cpu)) {
 665                         result = -ENODEV;
 666                         goto err_unreg;
 667                 }
 668                 data->cpu_feature = SYSTEM_INTEL_MSR_CAPABLE;
 669                 break;
 670         default:
 671                 dprintk("Unknown addr space %d\n",
 672                         (u32) (perf->control_register.space_id));
 673                 result = -ENODEV;
 674                 goto err_unreg;
 675         }
 676
 677         data->freq_table = kmalloc(sizeof(struct cpufreq_frequency_table) *
 678                     (perf->state_count+1), GFP_KERNEL);
 679         if (!data->freq_table) {
 680                 result = -ENOMEM;
 681                 goto err_unreg;
 682         }
 683
 684         /* detect transition latency */
 685         policy->cpuinfo.transition_latency = 0;
 686         for (i=0; i<perf->state_count; i++) {
 687                 if ((perf->states[i].transition_latency * 1000) >
 688                     policy->cpuinfo.transition_latency)
 689                         policy->cpuinfo.transition_latency =
 690                             perf->states[i].transition_latency * 1000;
 691         }
 692
 693         data->max_freq = perf->states[0].core_frequency * 1000;
 694         /* table init */
 695         for (i=0; i<perf->state_count; i++) {
 696                 if (i>0 && perf->states[i].core_frequency >=
 697                     data->freq_table[valid_states-1].frequency / 1000)
 698                         continue;
 699
 700                 data->freq_table[valid_states].index = i;
 701                 data->freq_table[valid_states].frequency =
 702                     perf->states[i].core_frequency * 1000;
 703                 valid_states++;
 704         }
 705         data->freq_table[valid_states].frequency = CPUFREQ_TABLE_END;
 706         perf->state = 0;
 707
 708         result = cpufreq_frequency_table_cpuinfo(policy, data->freq_table);
 709         if (result)
 710                 goto err_freqfree;
 711
 712         switch (perf->control_register.space_id) {
 713         case ACPI_ADR_SPACE_SYSTEM_IO:
 714                 /* Current speed is unknown and not detectable by IO port */
 715                 policy->cur = acpi_cpufreq_guess_freq(data, policy->cpu);
 716                 break;
 717         case ACPI_ADR_SPACE_FIXED_HARDWARE:
 718                 acpi_cpufreq_driver.get = get_cur_freq_on_cpu;
 719                 policy->cur = get_cur_freq_on_cpu(cpu);
 720                 break;
 721         default:
 722                 break;
 723         }
 724
 725         /* notify BIOS that we exist */
 726         acpi_processor_notify_smm(THIS_MODULE);
 727
 728         /* Check for APERF/MPERF support in hardware */
 729         if (c->x86_vendor == X86_VENDOR_INTEL && c->cpuid_level >= 6) {
 730                 unsigned int ecx;
 731                 ecx = cpuid_ecx(6);
 732                 if (ecx & CPUID_6_ECX_APERFMPERF_CAPABILITY)
 733                         acpi_cpufreq_driver.getavg = get_measured_perf;
 734         }
 735
 736         dprintk("CPU%u - ACPI performance management activated.\n", cpu);
 737         for (i = 0; i < perf->state_count; i++)
 738                 dprintk("     %cP%d: %d MHz, %d mW, %d uS\n",
 739                         (i == perf->state ? '*' : ' '), i,
 740                         (u32) perf->states[i].core_frequency,
 741                         (u32) perf->states[i].power,
 742                         (u32) perf->states[i].transition_latency);
 743
 744         cpufreq_frequency_table_get_attr(data->freq_table, policy->cpu);
 745
 746         /*
 747          * the first call to ->target() should result in us actually
 748          * writing something to the appropriate registers.
 749          */
 750         data->resume = 1;
 751
 752         return result;
 753
 754 err_freqfree:
 755         kfree(data->freq_table);
 756 err_unreg:
 757         acpi_processor_unregister_performance(perf, cpu);
 758 err_free:
 759         kfree(data);
 760         per_cpu(drv_data, cpu) = NULL;
 761
 762         return result;
 763 }
 764
 765 static int acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy)
 766 {
 767         struct acpi_cpufreq_data *data = per_cpu(drv_data, policy->cpu);
 768
 769         dprintk("acpi_cpufreq_cpu_exit\n");
 770
 771         if (data) {
 772                 cpufreq_frequency_table_put_attr(policy->cpu);
 773                 per_cpu(drv_data, policy->cpu) = NULL;
 774                 acpi_processor_unregister_performance(data->acpi_data,
 775                                                       policy->cpu);
 776                 kfree(data);
 777         }
 778
 779         return 0;
 780 }
 781
 782 static int acpi_cpufreq_resume(struct cpufreq_policy *policy)
 783 {
 784         struct acpi_cpufreq_data *data = per_cpu(drv_data, policy->cpu);
 785
 786         dprintk("acpi_cpufreq_resume\n");
 787
 788         data->resume = 1;
 789
 790         return 0;
 791 }
 792
 793 static struct freq_attr *acpi_cpufreq_attr[] = {
 794         &cpufreq_freq_attr_scaling_available_freqs,
 795         NULL,
 796 };
 797
 798 static struct cpufreq_driver acpi_cpufreq_driver = {
 799         .verify = acpi_cpufreq_verify,
 800         .target = acpi_cpufreq_target,
 801         .init = acpi_cpufreq_cpu_init,
 802         .exit = acpi_cpufreq_cpu_exit,
 803         .resume = acpi_cpufreq_resume,
 804         .name = "acpi-cpufreq",
 805         .owner = THIS_MODULE,
 806         .attr = acpi_cpufreq_attr,
 807 };
 808
 809 static int __init acpi_cpufreq_init(void)
 810 {
 811         int ret;
 812
 813         if (acpi_disabled)
 814                 return 0;
 815
 816         dprintk("acpi_cpufreq_init\n");
 817
 818         ret = acpi_cpufreq_early_init();
 819         if (ret)
 820                 return ret;
 821
 822         ret = cpufreq_register_driver(&acpi_cpufreq_driver);
 823         if (ret)
 824                 free_acpi_perf_data();
 825
 826         return ret;
 827 }
 828
 829 static void __exit acpi_cpufreq_exit(void)
 830 {
 831         dprintk("acpi_cpufreq_exit\n");
 832
 833         cpufreq_unregister_driver(&acpi_cpufreq_driver);
 834
 835         free_percpu(acpi_perf_data);
 836 }
 837
 838 module_param(acpi_pstate_strict, uint, 0644);
 839 MODULE_PARM_DESC(acpi_pstate_strict,
 840         "value 0 or non-zero. non-zero -> strict ACPI checks are "
 841         "performed during frequency changes.");
 842
 843 late_initcall(acpi_cpufreq_init);
 844 module_exit(acpi_cpufreq_exit);
 845
 846 MODULE_ALIAS("acpi");