linux/drivers/cpufreq/acpi-cpufreq.c
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   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * acpi-cpufreq.c - ACPI Processor P-States Driver
   4 *
   5 *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
   6 *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
   7 *  Copyright (C) 2002 - 2004 Dominik Brodowski <linux@brodo.de>
   8 *  Copyright (C) 2006       Denis Sadykov <denis.m.sadykov@intel.com>
   9 */
  10
  11#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  12
  13#include <linux/kernel.h>
  14#include <linux/module.h>
  15#include <linux/init.h>
  16#include <linux/smp.h>
  17#include <linux/sched.h>
  18#include <linux/cpufreq.h>
  19#include <linux/compiler.h>
  20#include <linux/dmi.h>
  21#include <linux/slab.h>
  22
  23#include <linux/acpi.h>
  24#include <linux/io.h>
  25#include <linux/delay.h>
  26#include <linux/uaccess.h>
  27
  28#include <acpi/processor.h>
  29#include <acpi/cppc_acpi.h>
  30
  31#include <asm/msr.h>
  32#include <asm/processor.h>
  33#include <asm/cpufeature.h>
  34#include <asm/cpu_device_id.h>
  35
  36MODULE_AUTHOR("Paul Diefenbaugh, Dominik Brodowski");
  37MODULE_DESCRIPTION("ACPI Processor P-States Driver");
  38MODULE_LICENSE("GPL");
  39
  40enum {
  41        UNDEFINED_CAPABLE = 0,
  42        SYSTEM_INTEL_MSR_CAPABLE,
  43        SYSTEM_AMD_MSR_CAPABLE,
  44        SYSTEM_IO_CAPABLE,
  45};
  46
  47#define INTEL_MSR_RANGE         (0xffff)
  48#define AMD_MSR_RANGE           (0x7)
  49#define HYGON_MSR_RANGE         (0x7)
  50
  51#define MSR_K7_HWCR_CPB_DIS     (1ULL << 25)
  52
  53struct acpi_cpufreq_data {
  54        unsigned int resume;
  55        unsigned int cpu_feature;
  56        unsigned int acpi_perf_cpu;
  57        cpumask_var_t freqdomain_cpus;
  58        void (*cpu_freq_write)(struct acpi_pct_register *reg, u32 val);
  59        u32 (*cpu_freq_read)(struct acpi_pct_register *reg);
  60};
  61
  62/* acpi_perf_data is a pointer to percpu data. */
  63static struct acpi_processor_performance __percpu *acpi_perf_data;
  64
  65static inline struct acpi_processor_performance *to_perf_data(struct acpi_cpufreq_data *data)
  66{
  67        return per_cpu_ptr(acpi_perf_data, data->acpi_perf_cpu);
  68}
  69
  70static struct cpufreq_driver acpi_cpufreq_driver;
  71
  72static unsigned int acpi_pstate_strict;
  73
  74static bool boost_state(unsigned int cpu)
  75{
  76        u32 lo, hi;
  77        u64 msr;
  78
  79        switch (boot_cpu_data.x86_vendor) {
  80        case X86_VENDOR_INTEL:
  81                rdmsr_on_cpu(cpu, MSR_IA32_MISC_ENABLE, &lo, &hi);
  82                msr = lo | ((u64)hi << 32);
  83                return !(msr & MSR_IA32_MISC_ENABLE_TURBO_DISABLE);
  84        case X86_VENDOR_HYGON:
  85        case X86_VENDOR_AMD:
  86                rdmsr_on_cpu(cpu, MSR_K7_HWCR, &lo, &hi);
  87                msr = lo | ((u64)hi << 32);
  88                return !(msr & MSR_K7_HWCR_CPB_DIS);
  89        }
  90        return false;
  91}
  92
  93static int boost_set_msr(bool enable)
  94{
  95        u32 msr_addr;
  96        u64 msr_mask, val;
  97
  98        switch (boot_cpu_data.x86_vendor) {
  99        case X86_VENDOR_INTEL:
 100                msr_addr = MSR_IA32_MISC_ENABLE;
 101                msr_mask = MSR_IA32_MISC_ENABLE_TURBO_DISABLE;
 102                break;
 103        case X86_VENDOR_HYGON:
 104        case X86_VENDOR_AMD:
 105                msr_addr = MSR_K7_HWCR;
 106                msr_mask = MSR_K7_HWCR_CPB_DIS;
 107                break;
 108        default:
 109                return -EINVAL;
 110        }
 111
 112        rdmsrl(msr_addr, val);
 113
 114        if (enable)
 115                val &= ~msr_mask;
 116        else
 117                val |= msr_mask;
 118
 119        wrmsrl(msr_addr, val);
 120        return 0;
 121}
 122
 123static void boost_set_msr_each(void *p_en)
 124{
 125        bool enable = (bool) p_en;
 126
 127        boost_set_msr(enable);
 128}
 129
 130static int set_boost(struct cpufreq_policy *policy, int val)
 131{
 132        on_each_cpu_mask(policy->cpus, boost_set_msr_each,
 133                         (void *)(long)val, 1);
 134        pr_debug("CPU %*pbl: Core Boosting %sabled.\n",
 135                 cpumask_pr_args(policy->cpus), val ? "en" : "dis");
 136
 137        return 0;
 138}
 139
 140static ssize_t show_freqdomain_cpus(struct cpufreq_policy *policy, char *buf)
 141{
 142        struct acpi_cpufreq_data *data = policy->driver_data;
 143
 144        if (unlikely(!data))
 145                return -ENODEV;
 146
 147        return cpufreq_show_cpus(data->freqdomain_cpus, buf);
 148}
 149
 150cpufreq_freq_attr_ro(freqdomain_cpus);
 151
 152#ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
 153static ssize_t store_cpb(struct cpufreq_policy *policy, const char *buf,
 154                         size_t count)
 155{
 156        int ret;
 157        unsigned int val = 0;
 158
 159        if (!acpi_cpufreq_driver.set_boost)
 160                return -EINVAL;
 161
 162        ret = kstrtouint(buf, 10, &val);
 163        if (ret || val > 1)
 164                return -EINVAL;
 165
 166        get_online_cpus();
 167        set_boost(policy, val);
 168        put_online_cpus();
 169
 170        return count;
 171}
 172
 173static ssize_t show_cpb(struct cpufreq_policy *policy, char *buf)
 174{
 175        return sprintf(buf, "%u\n", acpi_cpufreq_driver.boost_enabled);
 176}
 177
 178cpufreq_freq_attr_rw(cpb);
 179#endif
 180
 181static int check_est_cpu(unsigned int cpuid)
 182{
 183        struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
 184
 185        return cpu_has(cpu, X86_FEATURE_EST);
 186}
 187
 188static int check_amd_hwpstate_cpu(unsigned int cpuid)
 189{
 190        struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
 191
 192        return cpu_has(cpu, X86_FEATURE_HW_PSTATE);
 193}
 194
 195static unsigned extract_io(struct cpufreq_policy *policy, u32 value)
 196{
 197        struct acpi_cpufreq_data *data = policy->driver_data;
 198        struct acpi_processor_performance *perf;
 199        int i;
 200
 201        perf = to_perf_data(data);
 202
 203        for (i = 0; i < perf->state_count; i++) {
 204                if (value == perf->states[i].status)
 205                        return policy->freq_table[i].frequency;
 206        }
 207        return 0;
 208}
 209
 210static unsigned extract_msr(struct cpufreq_policy *policy, u32 msr)
 211{
 212        struct acpi_cpufreq_data *data = policy->driver_data;
 213        struct cpufreq_frequency_table *pos;
 214        struct acpi_processor_performance *perf;
 215
 216        if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
 217                msr &= AMD_MSR_RANGE;
 218        else if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON)
 219                msr &= HYGON_MSR_RANGE;
 220        else
 221                msr &= INTEL_MSR_RANGE;
 222
 223        perf = to_perf_data(data);
 224
 225        cpufreq_for_each_entry(pos, policy->freq_table)
 226                if (msr == perf->states[pos->driver_data].status)
 227                        return pos->frequency;
 228        return policy->freq_table[0].frequency;
 229}
 230
 231static unsigned extract_freq(struct cpufreq_policy *policy, u32 val)
 232{
 233        struct acpi_cpufreq_data *data = policy->driver_data;
 234
 235        switch (data->cpu_feature) {
 236        case SYSTEM_INTEL_MSR_CAPABLE:
 237        case SYSTEM_AMD_MSR_CAPABLE:
 238                return extract_msr(policy, val);
 239        case SYSTEM_IO_CAPABLE:
 240                return extract_io(policy, val);
 241        default:
 242                return 0;
 243        }
 244}
 245
 246static u32 cpu_freq_read_intel(struct acpi_pct_register *not_used)
 247{
 248        u32 val, dummy __always_unused;
 249
 250        rdmsr(MSR_IA32_PERF_CTL, val, dummy);
 251        return val;
 252}
 253
 254static void cpu_freq_write_intel(struct acpi_pct_register *not_used, u32 val)
 255{
 256        u32 lo, hi;
 257
 258        rdmsr(MSR_IA32_PERF_CTL, lo, hi);
 259        lo = (lo & ~INTEL_MSR_RANGE) | (val & INTEL_MSR_RANGE);
 260        wrmsr(MSR_IA32_PERF_CTL, lo, hi);
 261}
 262
 263static u32 cpu_freq_read_amd(struct acpi_pct_register *not_used)
 264{
 265        u32 val, dummy __always_unused;
 266
 267        rdmsr(MSR_AMD_PERF_CTL, val, dummy);
 268        return val;
 269}
 270
 271static void cpu_freq_write_amd(struct acpi_pct_register *not_used, u32 val)
 272{
 273        wrmsr(MSR_AMD_PERF_CTL, val, 0);
 274}
 275
 276static u32 cpu_freq_read_io(struct acpi_pct_register *reg)
 277{
 278        u32 val;
 279
 280        acpi_os_read_port(reg->address, &val, reg->bit_width);
 281        return val;
 282}
 283
 284static void cpu_freq_write_io(struct acpi_pct_register *reg, u32 val)
 285{
 286        acpi_os_write_port(reg->address, val, reg->bit_width);
 287}
 288
 289struct drv_cmd {
 290        struct acpi_pct_register *reg;
 291        u32 val;
 292        union {
 293                void (*write)(struct acpi_pct_register *reg, u32 val);
 294                u32 (*read)(struct acpi_pct_register *reg);
 295        } func;
 296};
 297
 298/* Called via smp_call_function_single(), on the target CPU */
 299static void do_drv_read(void *_cmd)
 300{
 301        struct drv_cmd *cmd = _cmd;
 302
 303        cmd->val = cmd->func.read(cmd->reg);
 304}
 305
 306static u32 drv_read(struct acpi_cpufreq_data *data, const struct cpumask *mask)
 307{
 308        struct acpi_processor_performance *perf = to_perf_data(data);
 309        struct drv_cmd cmd = {
 310                .reg = &perf->control_register,
 311                .func.read = data->cpu_freq_read,
 312        };
 313        int err;
 314
 315        err = smp_call_function_any(mask, do_drv_read, &cmd, 1);
 316        WARN_ON_ONCE(err);      /* smp_call_function_any() was buggy? */
 317        return cmd.val;
 318}
 319
 320/* Called via smp_call_function_many(), on the target CPUs */
 321static void do_drv_write(void *_cmd)
 322{
 323        struct drv_cmd *cmd = _cmd;
 324
 325        cmd->func.write(cmd->reg, cmd->val);
 326}
 327
 328static void drv_write(struct acpi_cpufreq_data *data,
 329                      const struct cpumask *mask, u32 val)
 330{
 331        struct acpi_processor_performance *perf = to_perf_data(data);
 332        struct drv_cmd cmd = {
 333                .reg = &perf->control_register,
 334                .val = val,
 335                .func.write = data->cpu_freq_write,
 336        };
 337        int this_cpu;
 338
 339        this_cpu = get_cpu();
 340        if (cpumask_test_cpu(this_cpu, mask))
 341                do_drv_write(&cmd);
 342
 343        smp_call_function_many(mask, do_drv_write, &cmd, 1);
 344        put_cpu();
 345}
 346
 347static u32 get_cur_val(const struct cpumask *mask, struct acpi_cpufreq_data *data)
 348{
 349        u32 val;
 350
 351        if (unlikely(cpumask_empty(mask)))
 352                return 0;
 353
 354        val = drv_read(data, mask);
 355
 356        pr_debug("%s = %u\n", __func__, val);
 357
 358        return val;
 359}
 360
 361static unsigned int get_cur_freq_on_cpu(unsigned int cpu)
 362{
 363        struct acpi_cpufreq_data *data;
 364        struct cpufreq_policy *policy;
 365        unsigned int freq;
 366        unsigned int cached_freq;
 367
 368        pr_debug("%s (%d)\n", __func__, cpu);
 369
 370        policy = cpufreq_cpu_get_raw(cpu);
 371        if (unlikely(!policy))
 372                return 0;
 373
 374        data = policy->driver_data;
 375        if (unlikely(!data || !policy->freq_table))
 376                return 0;
 377
 378        cached_freq = policy->freq_table[to_perf_data(data)->state].frequency;
 379        freq = extract_freq(policy, get_cur_val(cpumask_of(cpu), data));
 380        if (freq != cached_freq) {
 381                /*
 382                 * The dreaded BIOS frequency change behind our back.
 383                 * Force set the frequency on next target call.
 384                 */
 385                data->resume = 1;
 386        }
 387
 388        pr_debug("cur freq = %u\n", freq);
 389
 390        return freq;
 391}
 392
 393static unsigned int check_freqs(struct cpufreq_policy *policy,
 394                                const struct cpumask *mask, unsigned int freq)
 395{
 396        struct acpi_cpufreq_data *data = policy->driver_data;
 397        unsigned int cur_freq;
 398        unsigned int i;
 399
 400        for (i = 0; i < 100; i++) {
 401                cur_freq = extract_freq(policy, get_cur_val(mask, data));
 402                if (cur_freq == freq)
 403                        return 1;
 404                udelay(10);
 405        }
 406        return 0;
 407}
 408
 409static int acpi_cpufreq_target(struct cpufreq_policy *policy,
 410                               unsigned int index)
 411{
 412        struct acpi_cpufreq_data *data = policy->driver_data;
 413        struct acpi_processor_performance *perf;
 414        const struct cpumask *mask;
 415        unsigned int next_perf_state = 0; /* Index into perf table */
 416        int result = 0;
 417
 418        if (unlikely(!data)) {
 419                return -ENODEV;
 420        }
 421
 422        perf = to_perf_data(data);
 423        next_perf_state = policy->freq_table[index].driver_data;
 424        if (perf->state == next_perf_state) {
 425                if (unlikely(data->resume)) {
 426                        pr_debug("Called after resume, resetting to P%d\n",
 427                                next_perf_state);
 428                        data->resume = 0;
 429                } else {
 430                        pr_debug("Already at target state (P%d)\n",
 431                                next_perf_state);
 432                        return 0;
 433                }
 434        }
 435
 436        /*
 437         * The core won't allow CPUs to go away until the governor has been
 438         * stopped, so we can rely on the stability of policy->cpus.
 439         */
 440        mask = policy->shared_type == CPUFREQ_SHARED_TYPE_ANY ?
 441                cpumask_of(policy->cpu) : policy->cpus;
 442
 443        drv_write(data, mask, perf->states[next_perf_state].control);
 444
 445        if (acpi_pstate_strict) {
 446                if (!check_freqs(policy, mask,
 447                                 policy->freq_table[index].frequency)) {
 448                        pr_debug("%s (%d)\n", __func__, policy->cpu);
 449                        result = -EAGAIN;
 450                }
 451        }
 452
 453        if (!result)
 454                perf->state = next_perf_state;
 455
 456        return result;
 457}
 458
 459static unsigned int acpi_cpufreq_fast_switch(struct cpufreq_policy *policy,
 460                                             unsigned int target_freq)
 461{
 462        struct acpi_cpufreq_data *data = policy->driver_data;
 463        struct acpi_processor_performance *perf;
 464        struct cpufreq_frequency_table *entry;
 465        unsigned int next_perf_state, next_freq, index;
 466
 467        /*
 468         * Find the closest frequency above target_freq.
 469         */
 470        if (policy->cached_target_freq == target_freq)
 471                index = policy->cached_resolved_idx;
 472        else
 473                index = cpufreq_table_find_index_dl(policy, target_freq);
 474
 475        entry = &policy->freq_table[index];
 476        next_freq = entry->frequency;
 477        next_perf_state = entry->driver_data;
 478
 479        perf = to_perf_data(data);
 480        if (perf->state == next_perf_state) {
 481                if (unlikely(data->resume))
 482                        data->resume = 0;
 483                else
 484                        return next_freq;
 485        }
 486
 487        data->cpu_freq_write(&perf->control_register,
 488                             perf->states[next_perf_state].control);
 489        perf->state = next_perf_state;
 490        return next_freq;
 491}
 492
 493static unsigned long
 494acpi_cpufreq_guess_freq(struct acpi_cpufreq_data *data, unsigned int cpu)
 495{
 496        struct acpi_processor_performance *perf;
 497
 498        perf = to_perf_data(data);
 499        if (cpu_khz) {
 500                /* search the closest match to cpu_khz */
 501                unsigned int i;
 502                unsigned long freq;
 503                unsigned long freqn = perf->states[0].core_frequency * 1000;
 504
 505                for (i = 0; i < (perf->state_count-1); i++) {
 506                        freq = freqn;
 507                        freqn = perf->states[i+1].core_frequency * 1000;
 508                        if ((2 * cpu_khz) > (freqn + freq)) {
 509                                perf->state = i;
 510                                return freq;
 511                        }
 512                }
 513                perf->state = perf->state_count-1;
 514                return freqn;
 515        } else {
 516                /* assume CPU is at P0... */
 517                perf->state = 0;
 518                return perf->states[0].core_frequency * 1000;
 519        }
 520}
 521
 522static void free_acpi_perf_data(void)
 523{
 524        unsigned int i;
 525
 526        /* Freeing a NULL pointer is OK, and alloc_percpu zeroes. */
 527        for_each_possible_cpu(i)
 528                free_cpumask_var(per_cpu_ptr(acpi_perf_data, i)
 529                                 ->shared_cpu_map);
 530        free_percpu(acpi_perf_data);
 531}
 532
 533static int cpufreq_boost_online(unsigned int cpu)
 534{
 535        /*
 536         * On the CPU_UP path we simply keep the boost-disable flag
 537         * in sync with the current global state.
 538         */
 539        return boost_set_msr(acpi_cpufreq_driver.boost_enabled);
 540}
 541
 542static int cpufreq_boost_down_prep(unsigned int cpu)
 543{
 544        /*
 545         * Clear the boost-disable bit on the CPU_DOWN path so that
 546         * this cpu cannot block the remaining ones from boosting.
 547         */
 548        return boost_set_msr(1);
 549}
 550
 551/*
 552 * acpi_cpufreq_early_init - initialize ACPI P-States library
 553 *
 554 * Initialize the ACPI P-States library (drivers/acpi/processor_perflib.c)
 555 * in order to determine correct frequency and voltage pairings. We can
 556 * do _PDC and _PSD and find out the processor dependency for the
 557 * actual init that will happen later...
 558 */
 559static int __init acpi_cpufreq_early_init(void)
 560{
 561        unsigned int i;
 562        pr_debug("%s\n", __func__);
 563
 564        acpi_perf_data = alloc_percpu(struct acpi_processor_performance);
 565        if (!acpi_perf_data) {
 566                pr_debug("Memory allocation error for acpi_perf_data.\n");
 567                return -ENOMEM;
 568        }
 569        for_each_possible_cpu(i) {
 570                if (!zalloc_cpumask_var_node(
 571                        &per_cpu_ptr(acpi_perf_data, i)->shared_cpu_map,
 572                        GFP_KERNEL, cpu_to_node(i))) {
 573
 574                        /* Freeing a NULL pointer is OK: alloc_percpu zeroes. */
 575                        free_acpi_perf_data();
 576                        return -ENOMEM;
 577                }
 578        }
 579
 580        /* Do initialization in ACPI core */
 581        acpi_processor_preregister_performance(acpi_perf_data);
 582        return 0;
 583}
 584
 585#ifdef CONFIG_SMP
 586/*
 587 * Some BIOSes do SW_ANY coordination internally, either set it up in hw
 588 * or do it in BIOS firmware and won't inform about it to OS. If not
 589 * detected, this has a side effect of making CPU run at a different speed
 590 * than OS intended it to run at. Detect it and handle it cleanly.
 591 */
 592static int bios_with_sw_any_bug;
 593
 594static int sw_any_bug_found(const struct dmi_system_id *d)
 595{
 596        bios_with_sw_any_bug = 1;
 597        return 0;
 598}
 599
 600static const struct dmi_system_id sw_any_bug_dmi_table[] = {
 601        {
 602                .callback = sw_any_bug_found,
 603                .ident = "Supermicro Server X6DLP",
 604                .matches = {
 605                        DMI_MATCH(DMI_SYS_VENDOR, "Supermicro"),
 606                        DMI_MATCH(DMI_BIOS_VERSION, "080010"),
 607                        DMI_MATCH(DMI_PRODUCT_NAME, "X6DLP"),
 608                },
 609        },
 610        { }
 611};
 612
 613static int acpi_cpufreq_blacklist(struct cpuinfo_x86 *c)
 614{
 615        /* Intel Xeon Processor 7100 Series Specification Update
 616         * https://www.intel.com/Assets/PDF/specupdate/314554.pdf
 617         * AL30: A Machine Check Exception (MCE) Occurring during an
 618         * Enhanced Intel SpeedStep Technology Ratio Change May Cause
 619         * Both Processor Cores to Lock Up. */
 620        if (c->x86_vendor == X86_VENDOR_INTEL) {
 621                if ((c->x86 == 15) &&
 622                    (c->x86_model == 6) &&
 623                    (c->x86_stepping == 8)) {
 624                        pr_info("Intel(R) Xeon(R) 7100 Errata AL30, processors may lock up on frequency changes: disabling acpi-cpufreq\n");
 625                        return -ENODEV;
 626                    }
 627                }
 628        return 0;
 629}
 630#endif
 631
 632#ifdef CONFIG_ACPI_CPPC_LIB
 633static u64 get_max_boost_ratio(unsigned int cpu)
 634{
 635        struct cppc_perf_caps perf_caps;
 636        u64 highest_perf, nominal_perf;
 637        int ret;
 638
 639        if (acpi_pstate_strict)
 640                return 0;
 641
 642        ret = cppc_get_perf_caps(cpu, &perf_caps);
 643        if (ret) {
 644                pr_debug("CPU%d: Unable to get performance capabilities (%d)\n",
 645                         cpu, ret);
 646                return 0;
 647        }
 648
 649        if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
 650                highest_perf = amd_get_highest_perf();
 651        else
 652                highest_perf = perf_caps.highest_perf;
 653
 654        nominal_perf = perf_caps.nominal_perf;
 655
 656        if (!highest_perf || !nominal_perf) {
 657                pr_debug("CPU%d: highest or nominal performance missing\n", cpu);
 658                return 0;
 659        }
 660
 661        if (highest_perf < nominal_perf) {
 662                pr_debug("CPU%d: nominal performance above highest\n", cpu);
 663                return 0;
 664        }
 665
 666        return div_u64(highest_perf << SCHED_CAPACITY_SHIFT, nominal_perf);
 667}
 668#else
 669static inline u64 get_max_boost_ratio(unsigned int cpu) { return 0; }
 670#endif
 671
 672static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
 673{
 674        struct cpufreq_frequency_table *freq_table;
 675        struct acpi_processor_performance *perf;
 676        struct acpi_cpufreq_data *data;
 677        unsigned int cpu = policy->cpu;
 678        struct cpuinfo_x86 *c = &cpu_data(cpu);
 679        unsigned int valid_states = 0;
 680        unsigned int result = 0;
 681        u64 max_boost_ratio;
 682        unsigned int i;
 683#ifdef CONFIG_SMP
 684        static int blacklisted;
 685#endif
 686
 687        pr_debug("%s\n", __func__);
 688
 689#ifdef CONFIG_SMP
 690        if (blacklisted)
 691                return blacklisted;
 692        blacklisted = acpi_cpufreq_blacklist(c);
 693        if (blacklisted)
 694                return blacklisted;
 695#endif
 696
 697        data = kzalloc(sizeof(*data), GFP_KERNEL);
 698        if (!data)
 699                return -ENOMEM;
 700
 701        if (!zalloc_cpumask_var(&data->freqdomain_cpus, GFP_KERNEL)) {
 702                result = -ENOMEM;
 703                goto err_free;
 704        }
 705
 706        perf = per_cpu_ptr(acpi_perf_data, cpu);
 707        data->acpi_perf_cpu = cpu;
 708        policy->driver_data = data;
 709
 710        if (cpu_has(c, X86_FEATURE_CONSTANT_TSC))
 711                acpi_cpufreq_driver.flags |= CPUFREQ_CONST_LOOPS;
 712
 713        result = acpi_processor_register_performance(perf, cpu);
 714        if (result)
 715                goto err_free_mask;
 716
 717        policy->shared_type = perf->shared_type;
 718
 719        /*
 720         * Will let policy->cpus know about dependency only when software
 721         * coordination is required.
 722         */
 723        if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL ||
 724            policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {
 725                cpumask_copy(policy->cpus, perf->shared_cpu_map);
 726        }
 727        cpumask_copy(data->freqdomain_cpus, perf->shared_cpu_map);
 728
 729#ifdef CONFIG_SMP
 730        dmi_check_system(sw_any_bug_dmi_table);
 731        if (bios_with_sw_any_bug && !policy_is_shared(policy)) {
 732                policy->shared_type = CPUFREQ_SHARED_TYPE_ALL;
 733                cpumask_copy(policy->cpus, topology_core_cpumask(cpu));
 734        }
 735
 736        if (check_amd_hwpstate_cpu(cpu) && boot_cpu_data.x86 < 0x19 &&
 737            !acpi_pstate_strict) {
 738                cpumask_clear(policy->cpus);
 739                cpumask_set_cpu(cpu, policy->cpus);
 740                cpumask_copy(data->freqdomain_cpus,
 741                             topology_sibling_cpumask(cpu));
 742                policy->shared_type = CPUFREQ_SHARED_TYPE_HW;
 743                pr_info_once("overriding BIOS provided _PSD data\n");
 744        }
 745#endif
 746
 747        /* capability check */
 748        if (perf->state_count <= 1) {
 749                pr_debug("No P-States\n");
 750                result = -ENODEV;
 751                goto err_unreg;
 752        }
 753
 754        if (perf->control_register.space_id != perf->status_register.space_id) {
 755                result = -ENODEV;
 756                goto err_unreg;
 757        }
 758
 759        switch (perf->control_register.space_id) {
 760        case ACPI_ADR_SPACE_SYSTEM_IO:
 761                if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
 762                    boot_cpu_data.x86 == 0xf) {
 763                        pr_debug("AMD K8 systems must use native drivers.\n");
 764                        result = -ENODEV;
 765                        goto err_unreg;
 766                }
 767                pr_debug("SYSTEM IO addr space\n");
 768                data->cpu_feature = SYSTEM_IO_CAPABLE;
 769                data->cpu_freq_read = cpu_freq_read_io;
 770                data->cpu_freq_write = cpu_freq_write_io;
 771                break;
 772        case ACPI_ADR_SPACE_FIXED_HARDWARE:
 773                pr_debug("HARDWARE addr space\n");
 774                if (check_est_cpu(cpu)) {
 775                        data->cpu_feature = SYSTEM_INTEL_MSR_CAPABLE;
 776                        data->cpu_freq_read = cpu_freq_read_intel;
 777                        data->cpu_freq_write = cpu_freq_write_intel;
 778                        break;
 779                }
 780                if (check_amd_hwpstate_cpu(cpu)) {
 781                        data->cpu_feature = SYSTEM_AMD_MSR_CAPABLE;
 782                        data->cpu_freq_read = cpu_freq_read_amd;
 783                        data->cpu_freq_write = cpu_freq_write_amd;
 784                        break;
 785                }
 786                result = -ENODEV;
 787                goto err_unreg;
 788        default:
 789                pr_debug("Unknown addr space %d\n",
 790                        (u32) (perf->control_register.space_id));
 791                result = -ENODEV;
 792                goto err_unreg;
 793        }
 794
 795        freq_table = kcalloc(perf->state_count + 1, sizeof(*freq_table),
 796                             GFP_KERNEL);
 797        if (!freq_table) {
 798                result = -ENOMEM;
 799                goto err_unreg;
 800        }
 801
 802        /* detect transition latency */
 803        policy->cpuinfo.transition_latency = 0;
 804        for (i = 0; i < perf->state_count; i++) {
 805                if ((perf->states[i].transition_latency * 1000) >
 806                    policy->cpuinfo.transition_latency)
 807                        policy->cpuinfo.transition_latency =
 808                            perf->states[i].transition_latency * 1000;
 809        }
 810
 811        /* Check for high latency (>20uS) from buggy BIOSes, like on T42 */
 812        if (perf->control_register.space_id == ACPI_ADR_SPACE_FIXED_HARDWARE &&
 813            policy->cpuinfo.transition_latency > 20 * 1000) {
 814                policy->cpuinfo.transition_latency = 20 * 1000;
 815                pr_info_once("P-state transition latency capped at 20 uS\n");
 816        }
 817
 818        /* table init */
 819        for (i = 0; i < perf->state_count; i++) {
 820                if (i > 0 && perf->states[i].core_frequency >=
 821                    freq_table[valid_states-1].frequency / 1000)
 822                        continue;
 823
 824                freq_table[valid_states].driver_data = i;
 825                freq_table[valid_states].frequency =
 826                    perf->states[i].core_frequency * 1000;
 827                valid_states++;
 828        }
 829        freq_table[valid_states].frequency = CPUFREQ_TABLE_END;
 830
 831        max_boost_ratio = get_max_boost_ratio(cpu);
 832        if (max_boost_ratio) {
 833                unsigned int freq = freq_table[0].frequency;
 834
 835                /*
 836                 * Because the loop above sorts the freq_table entries in the
 837                 * descending order, freq is the maximum frequency in the table.
 838                 * Assume that it corresponds to the CPPC nominal frequency and
 839                 * use it to set cpuinfo.max_freq.
 840                 */
 841                policy->cpuinfo.max_freq = freq * max_boost_ratio >> SCHED_CAPACITY_SHIFT;
 842        } else {
 843                /*
 844                 * If the maximum "boost" frequency is unknown, ask the arch
 845                 * scale-invariance code to use the "nominal" performance for
 846                 * CPU utilization scaling so as to prevent the schedutil
 847                 * governor from selecting inadequate CPU frequencies.
 848                 */
 849                arch_set_max_freq_ratio(true);
 850        }
 851
 852        policy->freq_table = freq_table;
 853        perf->state = 0;
 854
 855        switch (perf->control_register.space_id) {
 856        case ACPI_ADR_SPACE_SYSTEM_IO:
 857                /*
 858                 * The core will not set policy->cur, because
 859                 * cpufreq_driver->get is NULL, so we need to set it here.
 860                 * However, we have to guess it, because the current speed is
 861                 * unknown and not detectable via IO ports.
 862                 */
 863                policy->cur = acpi_cpufreq_guess_freq(data, policy->cpu);
 864                break;
 865        case ACPI_ADR_SPACE_FIXED_HARDWARE:
 866                acpi_cpufreq_driver.get = get_cur_freq_on_cpu;
 867                break;
 868        default:
 869                break;
 870        }
 871
 872        /* notify BIOS that we exist */
 873        acpi_processor_notify_smm(THIS_MODULE);
 874
 875        pr_debug("CPU%u - ACPI performance management activated.\n", cpu);
 876        for (i = 0; i < perf->state_count; i++)
 877                pr_debug("     %cP%d: %d MHz, %d mW, %d uS\n",
 878                        (i == perf->state ? '*' : ' '), i,
 879                        (u32) perf->states[i].core_frequency,
 880                        (u32) perf->states[i].power,
 881                        (u32) perf->states[i].transition_latency);
 882
 883        /*
 884         * the first call to ->target() should result in us actually
 885         * writing something to the appropriate registers.
 886         */
 887        data->resume = 1;
 888
 889        policy->fast_switch_possible = !acpi_pstate_strict &&
 890                !(policy_is_shared(policy) && policy->shared_type != CPUFREQ_SHARED_TYPE_ANY);
 891
 892        return result;
 893
 894err_unreg:
 895        acpi_processor_unregister_performance(cpu);
 896err_free_mask:
 897        free_cpumask_var(data->freqdomain_cpus);
 898err_free:
 899        kfree(data);
 900        policy->driver_data = NULL;
 901
 902        return result;
 903}
 904
 905static int acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy)
 906{
 907        struct acpi_cpufreq_data *data = policy->driver_data;
 908
 909        pr_debug("%s\n", __func__);
 910
 911        policy->fast_switch_possible = false;
 912        policy->driver_data = NULL;
 913        acpi_processor_unregister_performance(data->acpi_perf_cpu);
 914        free_cpumask_var(data->freqdomain_cpus);
 915        kfree(policy->freq_table);
 916        kfree(data);
 917
 918        return 0;
 919}
 920
 921static void acpi_cpufreq_cpu_ready(struct cpufreq_policy *policy)
 922{
 923        struct acpi_processor_performance *perf = per_cpu_ptr(acpi_perf_data,
 924                                                              policy->cpu);
 925        unsigned int freq = policy->freq_table[0].frequency;
 926
 927        if (perf->states[0].core_frequency * 1000 != freq)
 928                pr_warn(FW_WARN "P-state 0 is not max freq\n");
 929}
 930
 931static int acpi_cpufreq_resume(struct cpufreq_policy *policy)
 932{
 933        struct acpi_cpufreq_data *data = policy->driver_data;
 934
 935        pr_debug("%s\n", __func__);
 936
 937        data->resume = 1;
 938
 939        return 0;
 940}
 941
 942static struct freq_attr *acpi_cpufreq_attr[] = {
 943        &cpufreq_freq_attr_scaling_available_freqs,
 944        &freqdomain_cpus,
 945#ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
 946        &cpb,
 947#endif
 948        NULL,
 949};
 950
 951static struct cpufreq_driver acpi_cpufreq_driver = {
 952        .verify         = cpufreq_generic_frequency_table_verify,
 953        .target_index   = acpi_cpufreq_target,
 954        .fast_switch    = acpi_cpufreq_fast_switch,
 955        .bios_limit     = acpi_processor_get_bios_limit,
 956        .init           = acpi_cpufreq_cpu_init,
 957        .exit           = acpi_cpufreq_cpu_exit,
 958        .ready          = acpi_cpufreq_cpu_ready,
 959        .resume         = acpi_cpufreq_resume,
 960        .name           = "acpi-cpufreq",
 961        .attr           = acpi_cpufreq_attr,
 962};
 963
 964static enum cpuhp_state acpi_cpufreq_online;
 965
 966static void __init acpi_cpufreq_boost_init(void)
 967{
 968        int ret;
 969
 970        if (!(boot_cpu_has(X86_FEATURE_CPB) || boot_cpu_has(X86_FEATURE_IDA))) {
 971                pr_debug("Boost capabilities not present in the processor\n");
 972                return;
 973        }
 974
 975        acpi_cpufreq_driver.set_boost = set_boost;
 976        acpi_cpufreq_driver.boost_enabled = boost_state(0);
 977
 978        /*
 979         * This calls the online callback on all online cpu and forces all
 980         * MSRs to the same value.
 981         */
 982        ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "cpufreq/acpi:online",
 983                                cpufreq_boost_online, cpufreq_boost_down_prep);
 984        if (ret < 0) {
 985                pr_err("acpi_cpufreq: failed to register hotplug callbacks\n");
 986                return;
 987        }
 988        acpi_cpufreq_online = ret;
 989}
 990
 991static void acpi_cpufreq_boost_exit(void)
 992{
 993        if (acpi_cpufreq_online > 0)
 994                cpuhp_remove_state_nocalls(acpi_cpufreq_online);
 995}
 996
 997static int __init acpi_cpufreq_init(void)
 998{
 999        int ret;
1000
1001        if (acpi_disabled)
1002                return -ENODEV;
1003
1004        /* don't keep reloading if cpufreq_driver exists */
1005        if (cpufreq_get_current_driver())
1006                return -EEXIST;
1007
1008        pr_debug("%s\n", __func__);
1009
1010        ret = acpi_cpufreq_early_init();
1011        if (ret)
1012                return ret;
1013
1014#ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
1015        /* this is a sysfs file with a strange name and an even stranger
1016         * semantic - per CPU instantiation, but system global effect.
1017         * Lets enable it only on AMD CPUs for compatibility reasons and
1018         * only if configured. This is considered legacy code, which
1019         * will probably be removed at some point in the future.
1020         */
1021        if (!check_amd_hwpstate_cpu(0)) {
1022                struct freq_attr **attr;
1023
1024                pr_debug("CPB unsupported, do not expose it\n");
1025
1026                for (attr = acpi_cpufreq_attr; *attr; attr++)
1027                        if (*attr == &cpb) {
1028                                *attr = NULL;
1029                                break;
1030                        }
1031        }
1032#endif
1033        acpi_cpufreq_boost_init();
1034
1035        ret = cpufreq_register_driver(&acpi_cpufreq_driver);
1036        if (ret) {
1037                free_acpi_perf_data();
1038                acpi_cpufreq_boost_exit();
1039        }
1040        return ret;
1041}
1042
1043static void __exit acpi_cpufreq_exit(void)
1044{
1045        pr_debug("%s\n", __func__);
1046
1047        acpi_cpufreq_boost_exit();
1048
1049        cpufreq_unregister_driver(&acpi_cpufreq_driver);
1050
1051        free_acpi_perf_data();
1052}
1053
1054module_param(acpi_pstate_strict, uint, 0644);
1055MODULE_PARM_DESC(acpi_pstate_strict,
1056        "value 0 or non-zero. non-zero -> strict ACPI checks are "
1057        "performed during frequency changes.");
1058
1059late_initcall(acpi_cpufreq_init);
1060module_exit(acpi_cpufreq_exit);
1061
1062static const struct x86_cpu_id __maybe_unused acpi_cpufreq_ids[] = {
1063        X86_MATCH_FEATURE(X86_FEATURE_ACPI, NULL),
1064        X86_MATCH_FEATURE(X86_FEATURE_HW_PSTATE, NULL),
1065        {}
1066};
1067MODULE_DEVICE_TABLE(x86cpu, acpi_cpufreq_ids);
1068
1069static const struct acpi_device_id __maybe_unused processor_device_ids[] = {
1070        {ACPI_PROCESSOR_OBJECT_HID, },
1071        {ACPI_PROCESSOR_DEVICE_HID, },
1072        {},
1073};
1074MODULE_DEVICE_TABLE(acpi, processor_device_ids);
1075
1076MODULE_ALIAS("acpi");
1077