drivers/cpufreq/acpi-cpufreq.c

   1 /*
   2  * acpi-cpufreq.c - ACPI Processor P-States Driver
   3  *
   4  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
   5  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
   6  *  Copyright (C) 2002 - 2004 Dominik Brodowski <linux@brodo.de>
   7  *  Copyright (C) 2006       Denis Sadykov <denis.m.sadykov@intel.com>
   8  *
   9  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  10  *
  11  *  This program is free software; you can redistribute it and/or modify
  12  *  it under the terms of the GNU General Public License as published by
  13  *  the Free Software Foundation; either version 2 of the License, or (at
  14  *  your option) any later version.
  15  *
  16  *  This program is distributed in the hope that it will be useful, but
  17  *  WITHOUT ANY WARRANTY; without even the implied warranty of
  18  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  19  *  General Public License for more details.
  20  *
  21  *  You should have received a copy of the GNU General Public License along
  22  *  with this program; if not, write to the Free Software Foundation, Inc.,
  23  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  24  *
  25  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  26  */
  27
  28 #include <linux/kernel.h>
  29 #include <linux/module.h>
  30 #include <linux/init.h>
  31 #include <linux/smp.h>
  32 #include <linux/sched.h>
  33 #include <linux/cpufreq.h>
  34 #include <linux/compiler.h>
  35 #include <linux/dmi.h>
  36 #include <linux/slab.h>
  37
  38 #include <linux/acpi.h>
  39 #include <linux/io.h>
  40 #include <linux/delay.h>
  41 #include <linux/uaccess.h>
  42
  43 #include <acpi/processor.h>
  44
  45 #include <asm/msr.h>
  46 #include <asm/processor.h>
  47 #include <asm/cpufeature.h>
  48
  49 MODULE_AUTHOR("Paul Diefenbaugh, Dominik Brodowski");
  50 MODULE_DESCRIPTION("ACPI Processor P-States Driver");
  51 MODULE_LICENSE("GPL");
  52
  53 #define PFX "acpi-cpufreq: "
  54
  55 enum {
  56         UNDEFINED_CAPABLE = 0,
  57         SYSTEM_INTEL_MSR_CAPABLE,
  58         SYSTEM_AMD_MSR_CAPABLE,
  59         SYSTEM_IO_CAPABLE,
  60 };
  61
  62 #define INTEL_MSR_RANGE         (0xffff)
  63 #define AMD_MSR_RANGE           (0x7)
  64
  65 #define MSR_K7_HWCR_CPB_DIS     (1ULL << 25)
  66
  67 struct acpi_cpufreq_data {
  68         struct acpi_processor_performance *acpi_data;
  69         struct cpufreq_frequency_table *freq_table;
  70         unsigned int resume;
  71         unsigned int cpu_feature;
  72         cpumask_var_t freqdomain_cpus;
  73 };
  74
  75 static DEFINE_PER_CPU(struct acpi_cpufreq_data *, acfreq_data);
  76
  77 /* acpi_perf_data is a pointer to percpu data. */
  78 static struct acpi_processor_performance __percpu *acpi_perf_data;
  79
  80 static struct cpufreq_driver acpi_cpufreq_driver;
  81
  82 static unsigned int acpi_pstate_strict;
  83 static bool boost_enabled, boost_supported;
  84 static struct msr __percpu *msrs;
  85
  86 static bool boost_state(unsigned int cpu)
  87 {
  88         u32 lo, hi;
  89         u64 msr;
  90
  91         switch (boot_cpu_data.x86_vendor) {
  92         case X86_VENDOR_INTEL:
  93                 rdmsr_on_cpu(cpu, MSR_IA32_MISC_ENABLE, &lo, &hi);
  94                 msr = lo | ((u64)hi << 32);
  95                 return !(msr & MSR_IA32_MISC_ENABLE_TURBO_DISABLE);
  96         case X86_VENDOR_AMD:
  97                 rdmsr_on_cpu(cpu, MSR_K7_HWCR, &lo, &hi);
  98                 msr = lo | ((u64)hi << 32);
  99                 return !(msr & MSR_K7_HWCR_CPB_DIS);
 100         }
 101         return false;
 102 }
 103
 104 static void boost_set_msrs(bool enable, const struct cpumask *cpumask)
 105 {
 106         u32 cpu;
 107         u32 msr_addr;
 108         u64 msr_mask;
 109
 110         switch (boot_cpu_data.x86_vendor) {
 111         case X86_VENDOR_INTEL:
 112                 msr_addr = MSR_IA32_MISC_ENABLE;
 113                 msr_mask = MSR_IA32_MISC_ENABLE_TURBO_DISABLE;
 114                 break;
 115         case X86_VENDOR_AMD:
 116                 msr_addr = MSR_K7_HWCR;
 117                 msr_mask = MSR_K7_HWCR_CPB_DIS;
 118                 break;
 119         default:
 120                 return;
 121         }
 122
 123         rdmsr_on_cpus(cpumask, msr_addr, msrs);
 124
 125         for_each_cpu(cpu, cpumask) {
 126                 struct msr *reg = per_cpu_ptr(msrs, cpu);
 127                 if (enable)
 128                         reg->q &= ~msr_mask;
 129                 else
 130                         reg->q |= msr_mask;
 131         }
 132
 133         wrmsr_on_cpus(cpumask, msr_addr, msrs);
 134 }
 135
 136 static ssize_t _store_boost(const char *buf, size_t count)
 137 {
 138         int ret;
 139         unsigned long val = 0;
 140
 141         if (!boost_supported)
 142                 return -EINVAL;
 143
 144         ret = kstrtoul(buf, 10, &val);
 145         if (ret || (val > 1))
 146                 return -EINVAL;
 147
 148         if ((val && boost_enabled) || (!val && !boost_enabled))
 149                 return count;
 150
 151         get_online_cpus();
 152
 153         boost_set_msrs(val, cpu_online_mask);
 154
 155         put_online_cpus();
 156
 157         boost_enabled = val;
 158         pr_debug("Core Boosting %sabled.\n", val ? "en" : "dis");
 159
 160         return count;
 161 }
 162
 163 static ssize_t store_global_boost(struct kobject *kobj, struct attribute *attr,
 164                                   const char *buf, size_t count)
 165 {
 166         return _store_boost(buf, count);
 167 }
 168
 169 static ssize_t show_global_boost(struct kobject *kobj,
 170                                  struct attribute *attr, char *buf)
 171 {
 172         return sprintf(buf, "%u\n", boost_enabled);
 173 }
 174
 175 static struct global_attr global_boost = __ATTR(boost, 0644,
 176                                                 show_global_boost,
 177                                                 store_global_boost);
 178
 179 static ssize_t show_freqdomain_cpus(struct cpufreq_policy *policy, char *buf)
 180 {
 181         struct acpi_cpufreq_data *data = per_cpu(acfreq_data, policy->cpu);
 182
 183         return cpufreq_show_cpus(data->freqdomain_cpus, buf);
 184 }
 185
 186 cpufreq_freq_attr_ro(freqdomain_cpus);
 187
 188 #ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
 189 static ssize_t store_cpb(struct cpufreq_policy *policy, const char *buf,
 190                          size_t count)
 191 {
 192         return _store_boost(buf, count);
 193 }
 194
 195 static ssize_t show_cpb(struct cpufreq_policy *policy, char *buf)
 196 {
 197         return sprintf(buf, "%u\n", boost_enabled);
 198 }
 199
 200 cpufreq_freq_attr_rw(cpb);
 201 #endif
 202
 203 static int check_est_cpu(unsigned int cpuid)
 204 {
 205         struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
 206
 207         return cpu_has(cpu, X86_FEATURE_EST);
 208 }
 209
 210 static int check_amd_hwpstate_cpu(unsigned int cpuid)
 211 {
 212         struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
 213
 214         return cpu_has(cpu, X86_FEATURE_HW_PSTATE);
 215 }
 216
 217 static unsigned extract_io(u32 value, struct acpi_cpufreq_data *data)
 218 {
 219         struct acpi_processor_performance *perf;
 220         int i;
 221
 222         perf = data->acpi_data;
 223
 224         for (i = 0; i < perf->state_count; i++) {
 225                 if (value == perf->states[i].status)
 226                         return data->freq_table[i].frequency;
 227         }
 228         return 0;
 229 }
 230
 231 static unsigned extract_msr(u32 msr, struct acpi_cpufreq_data *data)
 232 {
 233         int i;
 234         struct acpi_processor_performance *perf;
 235
 236         if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
 237                 msr &= AMD_MSR_RANGE;
 238         else
 239                 msr &= INTEL_MSR_RANGE;
 240
 241         perf = data->acpi_data;
 242
 243         for (i = 0; data->freq_table[i].frequency != CPUFREQ_TABLE_END; i++) {
 244                 if (msr == perf->states[data->freq_table[i].driver_data].status)
 245                         return data->freq_table[i].frequency;
 246         }
 247         return data->freq_table[0].frequency;
 248 }
 249
 250 static unsigned extract_freq(u32 val, struct acpi_cpufreq_data *data)
 251 {
 252         switch (data->cpu_feature) {
 253         case SYSTEM_INTEL_MSR_CAPABLE:
 254         case SYSTEM_AMD_MSR_CAPABLE:
 255                 return extract_msr(val, data);
 256         case SYSTEM_IO_CAPABLE:
 257                 return extract_io(val, data);
 258         default:
 259                 return 0;
 260         }
 261 }
 262
 263 struct msr_addr {
 264         u32 reg;
 265 };
 266
 267 struct io_addr {
 268         u16 port;
 269         u8 bit_width;
 270 };
 271
 272 struct drv_cmd {
 273         unsigned int type;
 274         const struct cpumask *mask;
 275         union {
 276                 struct msr_addr msr;
 277                 struct io_addr io;
 278         } addr;
 279         u32 val;
 280 };
 281
 282 /* Called via smp_call_function_single(), on the target CPU */
 283 static void do_drv_read(void *_cmd)
 284 {
 285         struct drv_cmd *cmd = _cmd;
 286         u32 h;
 287
 288         switch (cmd->type) {
 289         case SYSTEM_INTEL_MSR_CAPABLE:
 290         case SYSTEM_AMD_MSR_CAPABLE:
 291                 rdmsr(cmd->addr.msr.reg, cmd->val, h);
 292                 break;
 293         case SYSTEM_IO_CAPABLE:
 294                 acpi_os_read_port((acpi_io_address)cmd->addr.io.port,
 295                                 &cmd->val,
 296                                 (u32)cmd->addr.io.bit_width);
 297                 break;
 298         default:
 299                 break;
 300         }
 301 }
 302
 303 /* Called via smp_call_function_many(), on the target CPUs */
 304 static void do_drv_write(void *_cmd)
 305 {
 306         struct drv_cmd *cmd = _cmd;
 307         u32 lo, hi;
 308
 309         switch (cmd->type) {
 310         case SYSTEM_INTEL_MSR_CAPABLE:
 311                 rdmsr(cmd->addr.msr.reg, lo, hi);
 312                 lo = (lo & ~INTEL_MSR_RANGE) | (cmd->val & INTEL_MSR_RANGE);
 313                 wrmsr(cmd->addr.msr.reg, lo, hi);
 314                 break;
 315         case SYSTEM_AMD_MSR_CAPABLE:
 316                 wrmsr(cmd->addr.msr.reg, cmd->val, 0);
 317                 break;
 318         case SYSTEM_IO_CAPABLE:
 319                 acpi_os_write_port((acpi_io_address)cmd->addr.io.port,
 320                                 cmd->val,
 321                                 (u32)cmd->addr.io.bit_width);
 322                 break;
 323         default:
 324                 break;
 325         }
 326 }
 327
 328 static void drv_read(struct drv_cmd *cmd)
 329 {
 330         int err;
 331         cmd->val = 0;
 332
 333         err = smp_call_function_any(cmd->mask, do_drv_read, cmd, 1);
 334         WARN_ON_ONCE(err);      /* smp_call_function_any() was buggy? */
 335 }
 336
 337 static void drv_write(struct drv_cmd *cmd)
 338 {
 339         int this_cpu;
 340
 341         this_cpu = get_cpu();
 342         if (cpumask_test_cpu(this_cpu, cmd->mask))
 343                 do_drv_write(cmd);
 344         smp_call_function_many(cmd->mask, do_drv_write, cmd, 1);
 345         put_cpu();
 346 }
 347
 348 static u32 get_cur_val(const struct cpumask *mask)
 349 {
 350         struct acpi_processor_performance *perf;
 351         struct drv_cmd cmd;
 352
 353         if (unlikely(cpumask_empty(mask)))
 354                 return 0;
 355
 356         switch (per_cpu(acfreq_data, cpumask_first(mask))->cpu_feature) {
 357         case SYSTEM_INTEL_MSR_CAPABLE:
 358                 cmd.type = SYSTEM_INTEL_MSR_CAPABLE;
 359                 cmd.addr.msr.reg = MSR_IA32_PERF_CTL;
 360                 break;
 361         case SYSTEM_AMD_MSR_CAPABLE:
 362                 cmd.type = SYSTEM_AMD_MSR_CAPABLE;
 363                 cmd.addr.msr.reg = MSR_AMD_PERF_CTL;
 364                 break;
 365         case SYSTEM_IO_CAPABLE:
 366                 cmd.type = SYSTEM_IO_CAPABLE;
 367                 perf = per_cpu(acfreq_data, cpumask_first(mask))->acpi_data;
 368                 cmd.addr.io.port = perf->control_register.address;
 369                 cmd.addr.io.bit_width = perf->control_register.bit_width;
 370                 break;
 371         default:
 372                 return 0;
 373         }
 374
 375         cmd.mask = mask;
 376         drv_read(&cmd);
 377
 378         pr_debug("get_cur_val = %u\n", cmd.val);
 379
 380         return cmd.val;
 381 }
 382
 383 static unsigned int get_cur_freq_on_cpu(unsigned int cpu)
 384 {
 385         struct acpi_cpufreq_data *data = per_cpu(acfreq_data, cpu);
 386         unsigned int freq;
 387         unsigned int cached_freq;
 388
 389         pr_debug("get_cur_freq_on_cpu (%d)\n", cpu);
 390
 391         if (unlikely(data == NULL ||
 392                      data->acpi_data == NULL || data->freq_table == NULL)) {
 393                 return 0;
 394         }
 395
 396         cached_freq = data->freq_table[data->acpi_data->state].frequency;
 397         freq = extract_freq(get_cur_val(cpumask_of(cpu)), data);
 398         if (freq != cached_freq) {
 399                 /*
 400                  * The dreaded BIOS frequency change behind our back.
 401                  * Force set the frequency on next target call.
 402                  */
 403                 data->resume = 1;
 404         }
 405
 406         pr_debug("cur freq = %u\n", freq);
 407
 408         return freq;
 409 }
 410
 411 static unsigned int check_freqs(const struct cpumask *mask, unsigned int freq,
 412                                 struct acpi_cpufreq_data *data)
 413 {
 414         unsigned int cur_freq;
 415         unsigned int i;
 416
 417         for (i = 0; i < 100; i++) {
 418                 cur_freq = extract_freq(get_cur_val(mask), data);
 419                 if (cur_freq == freq)
 420                         return 1;
 421                 udelay(10);
 422         }
 423         return 0;
 424 }
 425
 426 static int acpi_cpufreq_target(struct cpufreq_policy *policy,
 427                                unsigned int index)
 428 {
 429         struct acpi_cpufreq_data *data = per_cpu(acfreq_data, policy->cpu);
 430         struct acpi_processor_performance *perf;
 431         struct cpufreq_freqs freqs;
 432         struct drv_cmd cmd;
 433         unsigned int next_perf_state = 0; /* Index into perf table */
 434         int result = 0;
 435
 436         pr_debug("acpi_cpufreq_target %d (%d)\n",
 437                         data->freq_table[index].frequency, policy->cpu);
 438
 439         if (unlikely(data == NULL ||
 440              data->acpi_data == NULL || data->freq_table == NULL)) {
 441                 return -ENODEV;
 442         }
 443
 444         perf = data->acpi_data;
 445         next_perf_state = data->freq_table[index].driver_data;
 446         if (perf->state == next_perf_state) {
 447                 if (unlikely(data->resume)) {
 448                         pr_debug("Called after resume, resetting to P%d\n",
 449                                 next_perf_state);
 450                         data->resume = 0;
 451                 } else {
 452                         pr_debug("Already at target state (P%d)\n",
 453                                 next_perf_state);
 454                         goto out;
 455                 }
 456         }
 457
 458         switch (data->cpu_feature) {
 459         case SYSTEM_INTEL_MSR_CAPABLE:
 460                 cmd.type = SYSTEM_INTEL_MSR_CAPABLE;
 461                 cmd.addr.msr.reg = MSR_IA32_PERF_CTL;
 462                 cmd.val = (u32) perf->states[next_perf_state].control;
 463                 break;
 464         case SYSTEM_AMD_MSR_CAPABLE:
 465                 cmd.type = SYSTEM_AMD_MSR_CAPABLE;
 466                 cmd.addr.msr.reg = MSR_AMD_PERF_CTL;
 467                 cmd.val = (u32) perf->states[next_perf_state].control;
 468                 break;
 469         case SYSTEM_IO_CAPABLE:
 470                 cmd.type = SYSTEM_IO_CAPABLE;
 471                 cmd.addr.io.port = perf->control_register.address;
 472                 cmd.addr.io.bit_width = perf->control_register.bit_width;
 473                 cmd.val = (u32) perf->states[next_perf_state].control;
 474                 break;
 475         default:
 476                 result = -ENODEV;
 477                 goto out;
 478         }
 479
 480         /* cpufreq holds the hotplug lock, so we are safe from here on */
 481         if (policy->shared_type != CPUFREQ_SHARED_TYPE_ANY)
 482                 cmd.mask = policy->cpus;
 483         else
 484                 cmd.mask = cpumask_of(policy->cpu);
 485
 486         freqs.old = perf->states[perf->state].core_frequency * 1000;
 487         freqs.new = data->freq_table[index].frequency;
 488         cpufreq_notify_transition(policy, &freqs, CPUFREQ_PRECHANGE);
 489
 490         drv_write(&cmd);
 491
 492         if (acpi_pstate_strict) {
 493                 if (!check_freqs(cmd.mask, freqs.new, data)) {
 494                         pr_debug("acpi_cpufreq_target failed (%d)\n",
 495                                 policy->cpu);
 496                         result = -EAGAIN;
 497                         freqs.new = freqs.old;
 498                 }
 499         }
 500
 501         cpufreq_notify_transition(policy, &freqs, CPUFREQ_POSTCHANGE);
 502
 503         if (!result)
 504                 perf->state = next_perf_state;
 505
 506 out:
 507         return result;
 508 }
 509
 510 static unsigned long
 511 acpi_cpufreq_guess_freq(struct acpi_cpufreq_data *data, unsigned int cpu)
 512 {
 513         struct acpi_processor_performance *perf = data->acpi_data;
 514
 515         if (cpu_khz) {
 516                 /* search the closest match to cpu_khz */
 517                 unsigned int i;
 518                 unsigned long freq;
 519                 unsigned long freqn = perf->states[0].core_frequency * 1000;
 520
 521                 for (i = 0; i < (perf->state_count-1); i++) {
 522                         freq = freqn;
 523                         freqn = perf->states[i+1].core_frequency * 1000;
 524                         if ((2 * cpu_khz) > (freqn + freq)) {
 525                                 perf->state = i;
 526                                 return freq;
 527                         }
 528                 }
 529                 perf->state = perf->state_count-1;
 530                 return freqn;
 531         } else {
 532                 /* assume CPU is at P0... */
 533                 perf->state = 0;
 534                 return perf->states[0].core_frequency * 1000;
 535         }
 536 }
 537
 538 static void free_acpi_perf_data(void)
 539 {
 540         unsigned int i;
 541
 542         /* Freeing a NULL pointer is OK, and alloc_percpu zeroes. */
 543         for_each_possible_cpu(i)
 544                 free_cpumask_var(per_cpu_ptr(acpi_perf_data, i)
 545                                  ->shared_cpu_map);
 546         free_percpu(acpi_perf_data);
 547 }
 548
 549 static int boost_notify(struct notifier_block *nb, unsigned long action,
 550                       void *hcpu)
 551 {
 552         unsigned cpu = (long)hcpu;
 553         const struct cpumask *cpumask;
 554
 555         cpumask = get_cpu_mask(cpu);
 556
 557         /*
 558          * Clear the boost-disable bit on the CPU_DOWN path so that
 559          * this cpu cannot block the remaining ones from boosting. On
 560          * the CPU_UP path we simply keep the boost-disable flag in
 561          * sync with the current global state.
 562          */
 563
 564         switch (action) {
 565         case CPU_UP_PREPARE:
 566         case CPU_UP_PREPARE_FROZEN:
 567                 boost_set_msrs(boost_enabled, cpumask);
 568                 break;
 569
 570         case CPU_DOWN_PREPARE:
 571         case CPU_DOWN_PREPARE_FROZEN:
 572                 boost_set_msrs(1, cpumask);
 573                 break;
 574
 575         default:
 576                 break;
 577         }
 578
 579         return NOTIFY_OK;
 580 }
 581
 582
 583 static struct notifier_block boost_nb = {
 584         .notifier_call          = boost_notify,
 585 };
 586
 587 /*
 588  * acpi_cpufreq_early_init - initialize ACPI P-States library
 589  *
 590  * Initialize the ACPI P-States library (drivers/acpi/processor_perflib.c)
 591  * in order to determine correct frequency and voltage pairings. We can
 592  * do _PDC and _PSD and find out the processor dependency for the
 593  * actual init that will happen later...
 594  */
 595 static int __init acpi_cpufreq_early_init(void)
 596 {
 597         unsigned int i;
 598         pr_debug("acpi_cpufreq_early_init\n");
 599
 600         acpi_perf_data = alloc_percpu(struct acpi_processor_performance);
 601         if (!acpi_perf_data) {
 602                 pr_debug("Memory allocation error for acpi_perf_data.\n");
 603                 return -ENOMEM;
 604         }
 605         for_each_possible_cpu(i) {
 606                 if (!zalloc_cpumask_var_node(
 607                         &per_cpu_ptr(acpi_perf_data, i)->shared_cpu_map,
 608                         GFP_KERNEL, cpu_to_node(i))) {
 609
 610                         /* Freeing a NULL pointer is OK: alloc_percpu zeroes. */
 611                         free_acpi_perf_data();
 612                         return -ENOMEM;
 613                 }
 614         }
 615
 616         /* Do initialization in ACPI core */
 617         acpi_processor_preregister_performance(acpi_perf_data);
 618         return 0;
 619 }
 620
 621 #ifdef CONFIG_SMP
 622 /*
 623  * Some BIOSes do SW_ANY coordination internally, either set it up in hw
 624  * or do it in BIOS firmware and won't inform about it to OS. If not
 625  * detected, this has a side effect of making CPU run at a different speed
 626  * than OS intended it to run at. Detect it and handle it cleanly.
 627  */
 628 static int bios_with_sw_any_bug;
 629
 630 static int sw_any_bug_found(const struct dmi_system_id *d)
 631 {
 632         bios_with_sw_any_bug = 1;
 633         return 0;
 634 }
 635
 636 static const struct dmi_system_id sw_any_bug_dmi_table[] = {
 637         {
 638                 .callback = sw_any_bug_found,
 639                 .ident = "Supermicro Server X6DLP",
 640                 .matches = {
 641                         DMI_MATCH(DMI_SYS_VENDOR, "Supermicro"),
 642                         DMI_MATCH(DMI_BIOS_VERSION, "080010"),
 643                         DMI_MATCH(DMI_PRODUCT_NAME, "X6DLP"),
 644                 },
 645         },
 646         { }
 647 };
 648
 649 static int acpi_cpufreq_blacklist(struct cpuinfo_x86 *c)
 650 {
 651         /* Intel Xeon Processor 7100 Series Specification Update
 652          * http://www.intel.com/Assets/PDF/specupdate/314554.pdf
 653          * AL30: A Machine Check Exception (MCE) Occurring during an
 654          * Enhanced Intel SpeedStep Technology Ratio Change May Cause
 655          * Both Processor Cores to Lock Up. */
 656         if (c->x86_vendor == X86_VENDOR_INTEL) {
 657                 if ((c->x86 == 15) &&
 658                     (c->x86_model == 6) &&
 659                     (c->x86_mask == 8)) {
 660                         printk(KERN_INFO "acpi-cpufreq: Intel(R) "
 661                             "Xeon(R) 7100 Errata AL30, processors may "
 662                             "lock up on frequency changes: disabling "
 663                             "acpi-cpufreq.\n");
 664                         return -ENODEV;
 665                     }
 666                 }
 667         return 0;
 668 }
 669 #endif
 670
 671 static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
 672 {
 673         unsigned int i;
 674         unsigned int valid_states = 0;
 675         unsigned int cpu = policy->cpu;
 676         struct acpi_cpufreq_data *data;
 677         unsigned int result = 0;
 678         struct cpuinfo_x86 *c = &cpu_data(policy->cpu);
 679         struct acpi_processor_performance *perf;
 680 #ifdef CONFIG_SMP
 681         static int blacklisted;
 682 #endif
 683
 684         pr_debug("acpi_cpufreq_cpu_init\n");
 685
 686 #ifdef CONFIG_SMP
 687         if (blacklisted)
 688                 return blacklisted;
 689         blacklisted = acpi_cpufreq_blacklist(c);
 690         if (blacklisted)
 691                 return blacklisted;
 692 #endif
 693
 694         data = kzalloc(sizeof(*data), GFP_KERNEL);
 695         if (!data)
 696                 return -ENOMEM;
 697
 698         if (!zalloc_cpumask_var(&data->freqdomain_cpus, GFP_KERNEL)) {
 699                 result = -ENOMEM;
 700                 goto err_free;
 701         }
 702
 703         data->acpi_data = per_cpu_ptr(acpi_perf_data, cpu);
 704         per_cpu(acfreq_data, cpu) = data;
 705
 706         if (cpu_has(c, X86_FEATURE_CONSTANT_TSC))
 707                 acpi_cpufreq_driver.flags |= CPUFREQ_CONST_LOOPS;
 708
 709         result = acpi_processor_register_performance(data->acpi_data, cpu);
 710         if (result)
 711                 goto err_free_mask;
 712
 713         perf = data->acpi_data;
 714         policy->shared_type = perf->shared_type;
 715
 716         /*
 717          * Will let policy->cpus know about dependency only when software
 718          * coordination is required.
 719          */
 720         if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL ||
 721             policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {
 722                 cpumask_copy(policy->cpus, perf->shared_cpu_map);
 723         }
 724         cpumask_copy(data->freqdomain_cpus, perf->shared_cpu_map);
 725
 726 #ifdef CONFIG_SMP
 727         dmi_check_system(sw_any_bug_dmi_table);
 728         if (bios_with_sw_any_bug && !policy_is_shared(policy)) {
 729                 policy->shared_type = CPUFREQ_SHARED_TYPE_ALL;
 730                 cpumask_copy(policy->cpus, cpu_core_mask(cpu));
 731         }
 732
 733         if (check_amd_hwpstate_cpu(cpu) && !acpi_pstate_strict) {
 734                 cpumask_clear(policy->cpus);
 735                 cpumask_set_cpu(cpu, policy->cpus);
 736                 cpumask_copy(data->freqdomain_cpus, cpu_sibling_mask(cpu));
 737                 policy->shared_type = CPUFREQ_SHARED_TYPE_HW;
 738                 pr_info_once(PFX "overriding BIOS provided _PSD data\n");
 739         }
 740 #endif
 741
 742         /* capability check */
 743         if (perf->state_count <= 1) {
 744                 pr_debug("No P-States\n");
 745                 result = -ENODEV;
 746                 goto err_unreg;
 747         }
 748
 749         if (perf->control_register.space_id != perf->status_register.space_id) {
 750                 result = -ENODEV;
 751                 goto err_unreg;
 752         }
 753
 754         switch (perf->control_register.space_id) {
 755         case ACPI_ADR_SPACE_SYSTEM_IO:
 756                 if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
 757                     boot_cpu_data.x86 == 0xf) {
 758                         pr_debug("AMD K8 systems must use native drivers.\n");
 759                         result = -ENODEV;
 760                         goto err_unreg;
 761                 }
 762                 pr_debug("SYSTEM IO addr space\n");
 763                 data->cpu_feature = SYSTEM_IO_CAPABLE;
 764                 break;
 765         case ACPI_ADR_SPACE_FIXED_HARDWARE:
 766                 pr_debug("HARDWARE addr space\n");
 767                 if (check_est_cpu(cpu)) {
 768                         data->cpu_feature = SYSTEM_INTEL_MSR_CAPABLE;
 769                         break;
 770                 }
 771                 if (check_amd_hwpstate_cpu(cpu)) {
 772                         data->cpu_feature = SYSTEM_AMD_MSR_CAPABLE;
 773                         break;
 774                 }
 775                 result = -ENODEV;
 776                 goto err_unreg;
 777         default:
 778                 pr_debug("Unknown addr space %d\n",
 779                         (u32) (perf->control_register.space_id));
 780                 result = -ENODEV;
 781                 goto err_unreg;
 782         }
 783
 784         data->freq_table = kmalloc(sizeof(*data->freq_table) *
 785                     (perf->state_count+1), GFP_KERNEL);
 786         if (!data->freq_table) {
 787                 result = -ENOMEM;
 788                 goto err_unreg;
 789         }
 790
 791         /* detect transition latency */
 792         policy->cpuinfo.transition_latency = 0;
 793         for (i = 0; i < perf->state_count; i++) {
 794                 if ((perf->states[i].transition_latency * 1000) >
 795                     policy->cpuinfo.transition_latency)
 796                         policy->cpuinfo.transition_latency =
 797                             perf->states[i].transition_latency * 1000;
 798         }
 799
 800         /* Check for high latency (>20uS) from buggy BIOSes, like on T42 */
 801         if (perf->control_register.space_id == ACPI_ADR_SPACE_FIXED_HARDWARE &&
 802             policy->cpuinfo.transition_latency > 20 * 1000) {
 803                 policy->cpuinfo.transition_latency = 20 * 1000;
 804                 printk_once(KERN_INFO
 805                             "P-state transition latency capped at 20 uS\n");
 806         }
 807
 808         /* table init */
 809         for (i = 0; i < perf->state_count; i++) {
 810                 if (i > 0 && perf->states[i].core_frequency >=
 811                     data->freq_table[valid_states-1].frequency / 1000)
 812                         continue;
 813
 814                 data->freq_table[valid_states].driver_data = i;
 815                 data->freq_table[valid_states].frequency =
 816                     perf->states[i].core_frequency * 1000;
 817                 valid_states++;
 818         }
 819         data->freq_table[valid_states].frequency = CPUFREQ_TABLE_END;
 820         perf->state = 0;
 821
 822         result = cpufreq_table_validate_and_show(policy, data->freq_table);
 823         if (result)
 824                 goto err_freqfree;
 825
 826         if (perf->states[0].core_frequency * 1000 != policy->cpuinfo.max_freq)
 827                 printk(KERN_WARNING FW_WARN "P-state 0 is not max freq\n");
 828
 829         switch (perf->control_register.space_id) {
 830         case ACPI_ADR_SPACE_SYSTEM_IO:
 831                 /*
 832                  * The core will not set policy->cur, because
 833                  * cpufreq_driver->get is NULL, so we need to set it here.
 834                  * However, we have to guess it, because the current speed is
 835                  * unknown and not detectable via IO ports.
 836                  */
 837                 policy->cur = acpi_cpufreq_guess_freq(data, policy->cpu);
 838                 break;
 839         case ACPI_ADR_SPACE_FIXED_HARDWARE:
 840                 acpi_cpufreq_driver.get = get_cur_freq_on_cpu;
 841                 break;
 842         default:
 843                 break;
 844         }
 845
 846         /* notify BIOS that we exist */
 847         acpi_processor_notify_smm(THIS_MODULE);
 848
 849         pr_debug("CPU%u - ACPI performance management activated.\n", cpu);
 850         for (i = 0; i < perf->state_count; i++)
 851                 pr_debug("     %cP%d: %d MHz, %d mW, %d uS\n",
 852                         (i == perf->state ? '*' : ' '), i,
 853                         (u32) perf->states[i].core_frequency,
 854                         (u32) perf->states[i].power,
 855                         (u32) perf->states[i].transition_latency);
 856
 857         /*
 858          * the first call to ->target() should result in us actually
 859          * writing something to the appropriate registers.
 860          */
 861         data->resume = 1;
 862
 863         return result;
 864
 865 err_freqfree:
 866         kfree(data->freq_table);
 867 err_unreg:
 868         acpi_processor_unregister_performance(perf, cpu);
 869 err_free_mask:
 870         free_cpumask_var(data->freqdomain_cpus);
 871 err_free:
 872         kfree(data);
 873         per_cpu(acfreq_data, cpu) = NULL;
 874
 875         return result;
 876 }
 877
 878 static int acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy)
 879 {
 880         struct acpi_cpufreq_data *data = per_cpu(acfreq_data, policy->cpu);
 881
 882         pr_debug("acpi_cpufreq_cpu_exit\n");
 883
 884         if (data) {
 885                 cpufreq_frequency_table_put_attr(policy->cpu);
 886                 per_cpu(acfreq_data, policy->cpu) = NULL;
 887                 acpi_processor_unregister_performance(data->acpi_data,
 888                                                       policy->cpu);
 889                 free_cpumask_var(data->freqdomain_cpus);
 890                 kfree(data->freq_table);
 891                 kfree(data);
 892         }
 893
 894         return 0;
 895 }
 896
 897 static int acpi_cpufreq_resume(struct cpufreq_policy *policy)
 898 {
 899         struct acpi_cpufreq_data *data = per_cpu(acfreq_data, policy->cpu);
 900
 901         pr_debug("acpi_cpufreq_resume\n");
 902
 903         data->resume = 1;
 904
 905         return 0;
 906 }
 907
 908 static struct freq_attr *acpi_cpufreq_attr[] = {
 909         &cpufreq_freq_attr_scaling_available_freqs,
 910         &freqdomain_cpus,
 911         NULL,   /* this is a placeholder for cpb, do not remove */
 912         NULL,
 913 };
 914
 915 static struct cpufreq_driver acpi_cpufreq_driver = {
 916         .verify         = cpufreq_generic_frequency_table_verify,
 917         .target_index   = acpi_cpufreq_target,
 918         .bios_limit     = acpi_processor_get_bios_limit,
 919         .init           = acpi_cpufreq_cpu_init,
 920         .exit           = acpi_cpufreq_cpu_exit,
 921         .resume         = acpi_cpufreq_resume,
 922         .name           = "acpi-cpufreq",
 923         .attr           = acpi_cpufreq_attr,
 924 };
 925
 926 static void __init acpi_cpufreq_boost_init(void)
 927 {
 928         if (boot_cpu_has(X86_FEATURE_CPB) || boot_cpu_has(X86_FEATURE_IDA)) {
 929                 msrs = msrs_alloc();
 930
 931                 if (!msrs)
 932                         return;
 933
 934                 boost_supported = true;
 935                 boost_enabled = boost_state(0);
 936
 937                 get_online_cpus();
 938
 939                 /* Force all MSRs to the same value */
 940                 boost_set_msrs(boost_enabled, cpu_online_mask);
 941
 942                 register_cpu_notifier(&boost_nb);
 943
 944                 put_online_cpus();
 945         } else
 946                 global_boost.attr.mode = 0444;
 947
 948         /* We create the boost file in any case, though for systems without
 949          * hardware support it will be read-only and hardwired to return 0.
 950          */
 951         if (cpufreq_sysfs_create_file(&(global_boost.attr)))
 952                 pr_warn(PFX "could not register global boost sysfs file\n");
 953         else
 954                 pr_debug("registered global boost sysfs file\n");
 955 }
 956
 957 static void __exit acpi_cpufreq_boost_exit(void)
 958 {
 959         cpufreq_sysfs_remove_file(&(global_boost.attr));
 960
 961         if (msrs) {
 962                 unregister_cpu_notifier(&boost_nb);
 963
 964                 msrs_free(msrs);
 965                 msrs = NULL;
 966         }
 967 }
 968
 969 static int __init acpi_cpufreq_init(void)
 970 {
 971         int ret;
 972
 973         if (acpi_disabled)
 974                 return -ENODEV;
 975
 976         /* don't keep reloading if cpufreq_driver exists */
 977         if (cpufreq_get_current_driver())
 978                 return -EEXIST;
 979
 980         pr_debug("acpi_cpufreq_init\n");
 981
 982         ret = acpi_cpufreq_early_init();
 983         if (ret)
 984                 return ret;
 985
 986 #ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
 987         /* this is a sysfs file with a strange name and an even stranger
 988          * semantic - per CPU instantiation, but system global effect.
 989          * Lets enable it only on AMD CPUs for compatibility reasons and
 990          * only if configured. This is considered legacy code, which
 991          * will probably be removed at some point in the future.
 992          */
 993         if (check_amd_hwpstate_cpu(0)) {
 994                 struct freq_attr **iter;
 995
 996                 pr_debug("adding sysfs entry for cpb\n");
 997
 998                 for (iter = acpi_cpufreq_attr; *iter != NULL; iter++)
 999                         ;
1000
1001                 /* make sure there is a terminator behind it */
1002                 if (iter[1] == NULL)
1003                         *iter = &cpb;
1004         }
1005 #endif
1006
1007         ret = cpufreq_register_driver(&acpi_cpufreq_driver);
1008         if (ret)
1009                 free_acpi_perf_data();
1010         else
1011                 acpi_cpufreq_boost_init();
1012
1013         return ret;
1014 }
1015
1016 static void __exit acpi_cpufreq_exit(void)
1017 {
1018         pr_debug("acpi_cpufreq_exit\n");
1019
1020         acpi_cpufreq_boost_exit();
1021
1022         cpufreq_unregister_driver(&acpi_cpufreq_driver);
1023
1024         free_acpi_perf_data();
1025 }
1026
1027 module_param(acpi_pstate_strict, uint, 0644);
1028 MODULE_PARM_DESC(acpi_pstate_strict,
1029         "value 0 or non-zero. non-zero -> strict ACPI checks are "
1030         "performed during frequency changes.");
1031
1032 late_initcall(acpi_cpufreq_init);
1033 module_exit(acpi_cpufreq_exit);
1034
1035 static const struct x86_cpu_id acpi_cpufreq_ids[] = {
1036         X86_FEATURE_MATCH(X86_FEATURE_ACPI),
1037         X86_FEATURE_MATCH(X86_FEATURE_HW_PSTATE),
1038         {}
1039 };
1040 MODULE_DEVICE_TABLE(x86cpu, acpi_cpufreq_ids);
1041
1042 static const struct acpi_device_id processor_device_ids[] = {
1043         {ACPI_PROCESSOR_OBJECT_HID, },
1044         {ACPI_PROCESSOR_DEVICE_HID, },
1045         {},
1046 };
1047 MODULE_DEVICE_TABLE(acpi, processor_device_ids);
1048
1049 MODULE_ALIAS("acpi");