diff options
Diffstat (limited to 'drivers/cpufreq/acpi-cpufreq.c')
-rw-r--r-- | drivers/cpufreq/acpi-cpufreq.c | 1048 |
1 files changed, 1048 insertions, 0 deletions
diff --git a/drivers/cpufreq/acpi-cpufreq.c b/drivers/cpufreq/acpi-cpufreq.c new file mode 100644 index 0000000000..37f1cdf46d --- /dev/null +++ b/drivers/cpufreq/acpi-cpufreq.c @@ -0,0 +1,1048 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * acpi-cpufreq.c - ACPI Processor P-States Driver + * + * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com> + * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com> + * Copyright (C) 2002 - 2004 Dominik Brodowski <linux@brodo.de> + * Copyright (C) 2006 Denis Sadykov <denis.m.sadykov@intel.com> + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/smp.h> +#include <linux/sched.h> +#include <linux/cpufreq.h> +#include <linux/compiler.h> +#include <linux/dmi.h> +#include <linux/slab.h> +#include <linux/string_helpers.h> +#include <linux/platform_device.h> + +#include <linux/acpi.h> +#include <linux/io.h> +#include <linux/delay.h> +#include <linux/uaccess.h> + +#include <acpi/processor.h> +#include <acpi/cppc_acpi.h> + +#include <asm/msr.h> +#include <asm/processor.h> +#include <asm/cpufeature.h> +#include <asm/cpu_device_id.h> + +MODULE_AUTHOR("Paul Diefenbaugh, Dominik Brodowski"); +MODULE_DESCRIPTION("ACPI Processor P-States Driver"); +MODULE_LICENSE("GPL"); + +enum { + UNDEFINED_CAPABLE = 0, + SYSTEM_INTEL_MSR_CAPABLE, + SYSTEM_AMD_MSR_CAPABLE, + SYSTEM_IO_CAPABLE, +}; + +#define INTEL_MSR_RANGE (0xffff) +#define AMD_MSR_RANGE (0x7) +#define HYGON_MSR_RANGE (0x7) + +#define MSR_K7_HWCR_CPB_DIS (1ULL << 25) + +struct acpi_cpufreq_data { + unsigned int resume; + unsigned int cpu_feature; + unsigned int acpi_perf_cpu; + cpumask_var_t freqdomain_cpus; + void (*cpu_freq_write)(struct acpi_pct_register *reg, u32 val); + u32 (*cpu_freq_read)(struct acpi_pct_register *reg); +}; + +/* acpi_perf_data is a pointer to percpu data. */ +static struct acpi_processor_performance __percpu *acpi_perf_data; + +static inline struct acpi_processor_performance *to_perf_data(struct acpi_cpufreq_data *data) +{ + return per_cpu_ptr(acpi_perf_data, data->acpi_perf_cpu); +} + +static struct cpufreq_driver acpi_cpufreq_driver; + +static unsigned int acpi_pstate_strict; + +static bool boost_state(unsigned int cpu) +{ + u32 lo, hi; + u64 msr; + + switch (boot_cpu_data.x86_vendor) { + case X86_VENDOR_INTEL: + case X86_VENDOR_CENTAUR: + case X86_VENDOR_ZHAOXIN: + rdmsr_on_cpu(cpu, MSR_IA32_MISC_ENABLE, &lo, &hi); + msr = lo | ((u64)hi << 32); + return !(msr & MSR_IA32_MISC_ENABLE_TURBO_DISABLE); + case X86_VENDOR_HYGON: + case X86_VENDOR_AMD: + rdmsr_on_cpu(cpu, MSR_K7_HWCR, &lo, &hi); + msr = lo | ((u64)hi << 32); + return !(msr & MSR_K7_HWCR_CPB_DIS); + } + return false; +} + +static int boost_set_msr(bool enable) +{ + u32 msr_addr; + u64 msr_mask, val; + + switch (boot_cpu_data.x86_vendor) { + case X86_VENDOR_INTEL: + case X86_VENDOR_CENTAUR: + case X86_VENDOR_ZHAOXIN: + msr_addr = MSR_IA32_MISC_ENABLE; + msr_mask = MSR_IA32_MISC_ENABLE_TURBO_DISABLE; + break; + case X86_VENDOR_HYGON: + case X86_VENDOR_AMD: + msr_addr = MSR_K7_HWCR; + msr_mask = MSR_K7_HWCR_CPB_DIS; + break; + default: + return -EINVAL; + } + + rdmsrl(msr_addr, val); + + if (enable) + val &= ~msr_mask; + else + val |= msr_mask; + + wrmsrl(msr_addr, val); + return 0; +} + +static void boost_set_msr_each(void *p_en) +{ + bool enable = (bool) p_en; + + boost_set_msr(enable); +} + +static int set_boost(struct cpufreq_policy *policy, int val) +{ + on_each_cpu_mask(policy->cpus, boost_set_msr_each, + (void *)(long)val, 1); + pr_debug("CPU %*pbl: Core Boosting %s.\n", + cpumask_pr_args(policy->cpus), str_enabled_disabled(val)); + + return 0; +} + +static ssize_t show_freqdomain_cpus(struct cpufreq_policy *policy, char *buf) +{ + struct acpi_cpufreq_data *data = policy->driver_data; + + if (unlikely(!data)) + return -ENODEV; + + return cpufreq_show_cpus(data->freqdomain_cpus, buf); +} + +cpufreq_freq_attr_ro(freqdomain_cpus); + +#ifdef CONFIG_X86_ACPI_CPUFREQ_CPB +static ssize_t store_cpb(struct cpufreq_policy *policy, const char *buf, + size_t count) +{ + int ret; + unsigned int val = 0; + + if (!acpi_cpufreq_driver.set_boost) + return -EINVAL; + + ret = kstrtouint(buf, 10, &val); + if (ret || val > 1) + return -EINVAL; + + cpus_read_lock(); + set_boost(policy, val); + cpus_read_unlock(); + + return count; +} + +static ssize_t show_cpb(struct cpufreq_policy *policy, char *buf) +{ + return sprintf(buf, "%u\n", acpi_cpufreq_driver.boost_enabled); +} + +cpufreq_freq_attr_rw(cpb); +#endif + +static int check_est_cpu(unsigned int cpuid) +{ + struct cpuinfo_x86 *cpu = &cpu_data(cpuid); + + return cpu_has(cpu, X86_FEATURE_EST); +} + +static int check_amd_hwpstate_cpu(unsigned int cpuid) +{ + struct cpuinfo_x86 *cpu = &cpu_data(cpuid); + + return cpu_has(cpu, X86_FEATURE_HW_PSTATE); +} + +static unsigned extract_io(struct cpufreq_policy *policy, u32 value) +{ + struct acpi_cpufreq_data *data = policy->driver_data; + struct acpi_processor_performance *perf; + int i; + + perf = to_perf_data(data); + + for (i = 0; i < perf->state_count; i++) { + if (value == perf->states[i].status) + return policy->freq_table[i].frequency; + } + return 0; +} + +static unsigned extract_msr(struct cpufreq_policy *policy, u32 msr) +{ + struct acpi_cpufreq_data *data = policy->driver_data; + struct cpufreq_frequency_table *pos; + struct acpi_processor_performance *perf; + + if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD) + msr &= AMD_MSR_RANGE; + else if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON) + msr &= HYGON_MSR_RANGE; + else + msr &= INTEL_MSR_RANGE; + + perf = to_perf_data(data); + + cpufreq_for_each_entry(pos, policy->freq_table) + if (msr == perf->states[pos->driver_data].status) + return pos->frequency; + return policy->freq_table[0].frequency; +} + +static unsigned extract_freq(struct cpufreq_policy *policy, u32 val) +{ + struct acpi_cpufreq_data *data = policy->driver_data; + + switch (data->cpu_feature) { + case SYSTEM_INTEL_MSR_CAPABLE: + case SYSTEM_AMD_MSR_CAPABLE: + return extract_msr(policy, val); + case SYSTEM_IO_CAPABLE: + return extract_io(policy, val); + default: + return 0; + } +} + +static u32 cpu_freq_read_intel(struct acpi_pct_register *not_used) +{ + u32 val, dummy __always_unused; + + rdmsr(MSR_IA32_PERF_CTL, val, dummy); + return val; +} + +static void cpu_freq_write_intel(struct acpi_pct_register *not_used, u32 val) +{ + u32 lo, hi; + + rdmsr(MSR_IA32_PERF_CTL, lo, hi); + lo = (lo & ~INTEL_MSR_RANGE) | (val & INTEL_MSR_RANGE); + wrmsr(MSR_IA32_PERF_CTL, lo, hi); +} + +static u32 cpu_freq_read_amd(struct acpi_pct_register *not_used) +{ + u32 val, dummy __always_unused; + + rdmsr(MSR_AMD_PERF_CTL, val, dummy); + return val; +} + +static void cpu_freq_write_amd(struct acpi_pct_register *not_used, u32 val) +{ + wrmsr(MSR_AMD_PERF_CTL, val, 0); +} + +static u32 cpu_freq_read_io(struct acpi_pct_register *reg) +{ + u32 val; + + acpi_os_read_port(reg->address, &val, reg->bit_width); + return val; +} + +static void cpu_freq_write_io(struct acpi_pct_register *reg, u32 val) +{ + acpi_os_write_port(reg->address, val, reg->bit_width); +} + +struct drv_cmd { + struct acpi_pct_register *reg; + u32 val; + union { + void (*write)(struct acpi_pct_register *reg, u32 val); + u32 (*read)(struct acpi_pct_register *reg); + } func; +}; + +/* Called via smp_call_function_single(), on the target CPU */ +static void do_drv_read(void *_cmd) +{ + struct drv_cmd *cmd = _cmd; + + cmd->val = cmd->func.read(cmd->reg); +} + +static u32 drv_read(struct acpi_cpufreq_data *data, const struct cpumask *mask) +{ + struct acpi_processor_performance *perf = to_perf_data(data); + struct drv_cmd cmd = { + .reg = &perf->control_register, + .func.read = data->cpu_freq_read, + }; + int err; + + err = smp_call_function_any(mask, do_drv_read, &cmd, 1); + WARN_ON_ONCE(err); /* smp_call_function_any() was buggy? */ + return cmd.val; +} + +/* Called via smp_call_function_many(), on the target CPUs */ +static void do_drv_write(void *_cmd) +{ + struct drv_cmd *cmd = _cmd; + + cmd->func.write(cmd->reg, cmd->val); +} + +static void drv_write(struct acpi_cpufreq_data *data, + const struct cpumask *mask, u32 val) +{ + struct acpi_processor_performance *perf = to_perf_data(data); + struct drv_cmd cmd = { + .reg = &perf->control_register, + .val = val, + .func.write = data->cpu_freq_write, + }; + int this_cpu; + + this_cpu = get_cpu(); + if (cpumask_test_cpu(this_cpu, mask)) + do_drv_write(&cmd); + + smp_call_function_many(mask, do_drv_write, &cmd, 1); + put_cpu(); +} + +static u32 get_cur_val(const struct cpumask *mask, struct acpi_cpufreq_data *data) +{ + u32 val; + + if (unlikely(cpumask_empty(mask))) + return 0; + + val = drv_read(data, mask); + + pr_debug("%s = %u\n", __func__, val); + + return val; +} + +static unsigned int get_cur_freq_on_cpu(unsigned int cpu) +{ + struct acpi_cpufreq_data *data; + struct cpufreq_policy *policy; + unsigned int freq; + unsigned int cached_freq; + + pr_debug("%s (%d)\n", __func__, cpu); + + policy = cpufreq_cpu_get_raw(cpu); + if (unlikely(!policy)) + return 0; + + data = policy->driver_data; + if (unlikely(!data || !policy->freq_table)) + return 0; + + cached_freq = policy->freq_table[to_perf_data(data)->state].frequency; + freq = extract_freq(policy, get_cur_val(cpumask_of(cpu), data)); + if (freq != cached_freq) { + /* + * The dreaded BIOS frequency change behind our back. + * Force set the frequency on next target call. + */ + data->resume = 1; + } + + pr_debug("cur freq = %u\n", freq); + + return freq; +} + +static unsigned int check_freqs(struct cpufreq_policy *policy, + const struct cpumask *mask, unsigned int freq) +{ + struct acpi_cpufreq_data *data = policy->driver_data; + unsigned int cur_freq; + unsigned int i; + + for (i = 0; i < 100; i++) { + cur_freq = extract_freq(policy, get_cur_val(mask, data)); + if (cur_freq == freq) + return 1; + udelay(10); + } + return 0; +} + +static int acpi_cpufreq_target(struct cpufreq_policy *policy, + unsigned int index) +{ + struct acpi_cpufreq_data *data = policy->driver_data; + struct acpi_processor_performance *perf; + const struct cpumask *mask; + unsigned int next_perf_state = 0; /* Index into perf table */ + int result = 0; + + if (unlikely(!data)) { + return -ENODEV; + } + + perf = to_perf_data(data); + next_perf_state = policy->freq_table[index].driver_data; + if (perf->state == next_perf_state) { + if (unlikely(data->resume)) { + pr_debug("Called after resume, resetting to P%d\n", + next_perf_state); + data->resume = 0; + } else { + pr_debug("Already at target state (P%d)\n", + next_perf_state); + return 0; + } + } + + /* + * The core won't allow CPUs to go away until the governor has been + * stopped, so we can rely on the stability of policy->cpus. + */ + mask = policy->shared_type == CPUFREQ_SHARED_TYPE_ANY ? + cpumask_of(policy->cpu) : policy->cpus; + + drv_write(data, mask, perf->states[next_perf_state].control); + + if (acpi_pstate_strict) { + if (!check_freqs(policy, mask, + policy->freq_table[index].frequency)) { + pr_debug("%s (%d)\n", __func__, policy->cpu); + result = -EAGAIN; + } + } + + if (!result) + perf->state = next_perf_state; + + return result; +} + +static unsigned int acpi_cpufreq_fast_switch(struct cpufreq_policy *policy, + unsigned int target_freq) +{ + struct acpi_cpufreq_data *data = policy->driver_data; + struct acpi_processor_performance *perf; + struct cpufreq_frequency_table *entry; + unsigned int next_perf_state, next_freq, index; + + /* + * Find the closest frequency above target_freq. + */ + if (policy->cached_target_freq == target_freq) + index = policy->cached_resolved_idx; + else + index = cpufreq_table_find_index_dl(policy, target_freq, + false); + + entry = &policy->freq_table[index]; + next_freq = entry->frequency; + next_perf_state = entry->driver_data; + + perf = to_perf_data(data); + if (perf->state == next_perf_state) { + if (unlikely(data->resume)) + data->resume = 0; + else + return next_freq; + } + + data->cpu_freq_write(&perf->control_register, + perf->states[next_perf_state].control); + perf->state = next_perf_state; + return next_freq; +} + +static unsigned long +acpi_cpufreq_guess_freq(struct acpi_cpufreq_data *data, unsigned int cpu) +{ + struct acpi_processor_performance *perf; + + perf = to_perf_data(data); + if (cpu_khz) { + /* search the closest match to cpu_khz */ + unsigned int i; + unsigned long freq; + unsigned long freqn = perf->states[0].core_frequency * 1000; + + for (i = 0; i < (perf->state_count-1); i++) { + freq = freqn; + freqn = perf->states[i+1].core_frequency * 1000; + if ((2 * cpu_khz) > (freqn + freq)) { + perf->state = i; + return freq; + } + } + perf->state = perf->state_count-1; + return freqn; + } else { + /* assume CPU is at P0... */ + perf->state = 0; + return perf->states[0].core_frequency * 1000; + } +} + +static void free_acpi_perf_data(void) +{ + unsigned int i; + + /* Freeing a NULL pointer is OK, and alloc_percpu zeroes. */ + for_each_possible_cpu(i) + free_cpumask_var(per_cpu_ptr(acpi_perf_data, i) + ->shared_cpu_map); + free_percpu(acpi_perf_data); +} + +static int cpufreq_boost_down_prep(unsigned int cpu) +{ + /* + * Clear the boost-disable bit on the CPU_DOWN path so that + * this cpu cannot block the remaining ones from boosting. + */ + return boost_set_msr(1); +} + +/* + * acpi_cpufreq_early_init - initialize ACPI P-States library + * + * Initialize the ACPI P-States library (drivers/acpi/processor_perflib.c) + * in order to determine correct frequency and voltage pairings. We can + * do _PDC and _PSD and find out the processor dependency for the + * actual init that will happen later... + */ +static int __init acpi_cpufreq_early_init(void) +{ + unsigned int i; + pr_debug("%s\n", __func__); + + acpi_perf_data = alloc_percpu(struct acpi_processor_performance); + if (!acpi_perf_data) { + pr_debug("Memory allocation error for acpi_perf_data.\n"); + return -ENOMEM; + } + for_each_possible_cpu(i) { + if (!zalloc_cpumask_var_node( + &per_cpu_ptr(acpi_perf_data, i)->shared_cpu_map, + GFP_KERNEL, cpu_to_node(i))) { + + /* Freeing a NULL pointer is OK: alloc_percpu zeroes. */ + free_acpi_perf_data(); + return -ENOMEM; + } + } + + /* Do initialization in ACPI core */ + acpi_processor_preregister_performance(acpi_perf_data); + return 0; +} + +#ifdef CONFIG_SMP +/* + * Some BIOSes do SW_ANY coordination internally, either set it up in hw + * or do it in BIOS firmware and won't inform about it to OS. If not + * detected, this has a side effect of making CPU run at a different speed + * than OS intended it to run at. Detect it and handle it cleanly. + */ +static int bios_with_sw_any_bug; + +static int sw_any_bug_found(const struct dmi_system_id *d) +{ + bios_with_sw_any_bug = 1; + return 0; +} + +static const struct dmi_system_id sw_any_bug_dmi_table[] = { + { + .callback = sw_any_bug_found, + .ident = "Supermicro Server X6DLP", + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "Supermicro"), + DMI_MATCH(DMI_BIOS_VERSION, "080010"), + DMI_MATCH(DMI_PRODUCT_NAME, "X6DLP"), + }, + }, + { } +}; + +static int acpi_cpufreq_blacklist(struct cpuinfo_x86 *c) +{ + /* Intel Xeon Processor 7100 Series Specification Update + * https://www.intel.com/Assets/PDF/specupdate/314554.pdf + * AL30: A Machine Check Exception (MCE) Occurring during an + * Enhanced Intel SpeedStep Technology Ratio Change May Cause + * Both Processor Cores to Lock Up. */ + if (c->x86_vendor == X86_VENDOR_INTEL) { + if ((c->x86 == 15) && + (c->x86_model == 6) && + (c->x86_stepping == 8)) { + pr_info("Intel(R) Xeon(R) 7100 Errata AL30, processors may lock up on frequency changes: disabling acpi-cpufreq\n"); + return -ENODEV; + } + } + return 0; +} +#endif + +#ifdef CONFIG_ACPI_CPPC_LIB +static u64 get_max_boost_ratio(unsigned int cpu) +{ + struct cppc_perf_caps perf_caps; + u64 highest_perf, nominal_perf; + int ret; + + if (acpi_pstate_strict) + return 0; + + ret = cppc_get_perf_caps(cpu, &perf_caps); + if (ret) { + pr_debug("CPU%d: Unable to get performance capabilities (%d)\n", + cpu, ret); + return 0; + } + + if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD) + highest_perf = amd_get_highest_perf(); + else + highest_perf = perf_caps.highest_perf; + + nominal_perf = perf_caps.nominal_perf; + + if (!highest_perf || !nominal_perf) { + pr_debug("CPU%d: highest or nominal performance missing\n", cpu); + return 0; + } + + if (highest_perf < nominal_perf) { + pr_debug("CPU%d: nominal performance above highest\n", cpu); + return 0; + } + + return div_u64(highest_perf << SCHED_CAPACITY_SHIFT, nominal_perf); +} +#else +static inline u64 get_max_boost_ratio(unsigned int cpu) { return 0; } +#endif + +static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy) +{ + struct cpufreq_frequency_table *freq_table; + struct acpi_processor_performance *perf; + struct acpi_cpufreq_data *data; + unsigned int cpu = policy->cpu; + struct cpuinfo_x86 *c = &cpu_data(cpu); + unsigned int valid_states = 0; + unsigned int result = 0; + u64 max_boost_ratio; + unsigned int i; +#ifdef CONFIG_SMP + static int blacklisted; +#endif + + pr_debug("%s\n", __func__); + +#ifdef CONFIG_SMP + if (blacklisted) + return blacklisted; + blacklisted = acpi_cpufreq_blacklist(c); + if (blacklisted) + return blacklisted; +#endif + + data = kzalloc(sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + if (!zalloc_cpumask_var(&data->freqdomain_cpus, GFP_KERNEL)) { + result = -ENOMEM; + goto err_free; + } + + perf = per_cpu_ptr(acpi_perf_data, cpu); + data->acpi_perf_cpu = cpu; + policy->driver_data = data; + + if (cpu_has(c, X86_FEATURE_CONSTANT_TSC)) + acpi_cpufreq_driver.flags |= CPUFREQ_CONST_LOOPS; + + result = acpi_processor_register_performance(perf, cpu); + if (result) + goto err_free_mask; + + policy->shared_type = perf->shared_type; + + /* + * Will let policy->cpus know about dependency only when software + * coordination is required. + */ + if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL || + policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) { + cpumask_copy(policy->cpus, perf->shared_cpu_map); + } + cpumask_copy(data->freqdomain_cpus, perf->shared_cpu_map); + +#ifdef CONFIG_SMP + dmi_check_system(sw_any_bug_dmi_table); + if (bios_with_sw_any_bug && !policy_is_shared(policy)) { + policy->shared_type = CPUFREQ_SHARED_TYPE_ALL; + cpumask_copy(policy->cpus, topology_core_cpumask(cpu)); + } + + if (check_amd_hwpstate_cpu(cpu) && boot_cpu_data.x86 < 0x19 && + !acpi_pstate_strict) { + cpumask_clear(policy->cpus); + cpumask_set_cpu(cpu, policy->cpus); + cpumask_copy(data->freqdomain_cpus, + topology_sibling_cpumask(cpu)); + policy->shared_type = CPUFREQ_SHARED_TYPE_HW; + pr_info_once("overriding BIOS provided _PSD data\n"); + } +#endif + + /* capability check */ + if (perf->state_count <= 1) { + pr_debug("No P-States\n"); + result = -ENODEV; + goto err_unreg; + } + + if (perf->control_register.space_id != perf->status_register.space_id) { + result = -ENODEV; + goto err_unreg; + } + + switch (perf->control_register.space_id) { + case ACPI_ADR_SPACE_SYSTEM_IO: + if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD && + boot_cpu_data.x86 == 0xf) { + pr_debug("AMD K8 systems must use native drivers.\n"); + result = -ENODEV; + goto err_unreg; + } + pr_debug("SYSTEM IO addr space\n"); + data->cpu_feature = SYSTEM_IO_CAPABLE; + data->cpu_freq_read = cpu_freq_read_io; + data->cpu_freq_write = cpu_freq_write_io; + break; + case ACPI_ADR_SPACE_FIXED_HARDWARE: + pr_debug("HARDWARE addr space\n"); + if (check_est_cpu(cpu)) { + data->cpu_feature = SYSTEM_INTEL_MSR_CAPABLE; + data->cpu_freq_read = cpu_freq_read_intel; + data->cpu_freq_write = cpu_freq_write_intel; + break; + } + if (check_amd_hwpstate_cpu(cpu)) { + data->cpu_feature = SYSTEM_AMD_MSR_CAPABLE; + data->cpu_freq_read = cpu_freq_read_amd; + data->cpu_freq_write = cpu_freq_write_amd; + break; + } + result = -ENODEV; + goto err_unreg; + default: + pr_debug("Unknown addr space %d\n", + (u32) (perf->control_register.space_id)); + result = -ENODEV; + goto err_unreg; + } + + freq_table = kcalloc(perf->state_count + 1, sizeof(*freq_table), + GFP_KERNEL); + if (!freq_table) { + result = -ENOMEM; + goto err_unreg; + } + + /* detect transition latency */ + policy->cpuinfo.transition_latency = 0; + for (i = 0; i < perf->state_count; i++) { + if ((perf->states[i].transition_latency * 1000) > + policy->cpuinfo.transition_latency) + policy->cpuinfo.transition_latency = + perf->states[i].transition_latency * 1000; + } + + /* Check for high latency (>20uS) from buggy BIOSes, like on T42 */ + if (perf->control_register.space_id == ACPI_ADR_SPACE_FIXED_HARDWARE && + policy->cpuinfo.transition_latency > 20 * 1000) { + policy->cpuinfo.transition_latency = 20 * 1000; + pr_info_once("P-state transition latency capped at 20 uS\n"); + } + + /* table init */ + for (i = 0; i < perf->state_count; i++) { + if (i > 0 && perf->states[i].core_frequency >= + freq_table[valid_states-1].frequency / 1000) + continue; + + freq_table[valid_states].driver_data = i; + freq_table[valid_states].frequency = + perf->states[i].core_frequency * 1000; + valid_states++; + } + freq_table[valid_states].frequency = CPUFREQ_TABLE_END; + + max_boost_ratio = get_max_boost_ratio(cpu); + if (max_boost_ratio) { + unsigned int freq = freq_table[0].frequency; + + /* + * Because the loop above sorts the freq_table entries in the + * descending order, freq is the maximum frequency in the table. + * Assume that it corresponds to the CPPC nominal frequency and + * use it to set cpuinfo.max_freq. + */ + policy->cpuinfo.max_freq = freq * max_boost_ratio >> SCHED_CAPACITY_SHIFT; + } else { + /* + * If the maximum "boost" frequency is unknown, ask the arch + * scale-invariance code to use the "nominal" performance for + * CPU utilization scaling so as to prevent the schedutil + * governor from selecting inadequate CPU frequencies. + */ + arch_set_max_freq_ratio(true); + } + + policy->freq_table = freq_table; + perf->state = 0; + + switch (perf->control_register.space_id) { + case ACPI_ADR_SPACE_SYSTEM_IO: + /* + * The core will not set policy->cur, because + * cpufreq_driver->get is NULL, so we need to set it here. + * However, we have to guess it, because the current speed is + * unknown and not detectable via IO ports. + */ + policy->cur = acpi_cpufreq_guess_freq(data, policy->cpu); + break; + case ACPI_ADR_SPACE_FIXED_HARDWARE: + acpi_cpufreq_driver.get = get_cur_freq_on_cpu; + break; + default: + break; + } + + /* notify BIOS that we exist */ + acpi_processor_notify_smm(THIS_MODULE); + + pr_debug("CPU%u - ACPI performance management activated.\n", cpu); + for (i = 0; i < perf->state_count; i++) + pr_debug(" %cP%d: %d MHz, %d mW, %d uS\n", + (i == perf->state ? '*' : ' '), i, + (u32) perf->states[i].core_frequency, + (u32) perf->states[i].power, + (u32) perf->states[i].transition_latency); + + /* + * the first call to ->target() should result in us actually + * writing something to the appropriate registers. + */ + data->resume = 1; + + policy->fast_switch_possible = !acpi_pstate_strict && + !(policy_is_shared(policy) && policy->shared_type != CPUFREQ_SHARED_TYPE_ANY); + + if (perf->states[0].core_frequency * 1000 != freq_table[0].frequency) + pr_warn(FW_WARN "P-state 0 is not max freq\n"); + + if (acpi_cpufreq_driver.set_boost) + set_boost(policy, acpi_cpufreq_driver.boost_enabled); + + return result; + +err_unreg: + acpi_processor_unregister_performance(cpu); +err_free_mask: + free_cpumask_var(data->freqdomain_cpus); +err_free: + kfree(data); + policy->driver_data = NULL; + + return result; +} + +static int acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy) +{ + struct acpi_cpufreq_data *data = policy->driver_data; + + pr_debug("%s\n", __func__); + + cpufreq_boost_down_prep(policy->cpu); + policy->fast_switch_possible = false; + policy->driver_data = NULL; + acpi_processor_unregister_performance(data->acpi_perf_cpu); + free_cpumask_var(data->freqdomain_cpus); + kfree(policy->freq_table); + kfree(data); + + return 0; +} + +static int acpi_cpufreq_resume(struct cpufreq_policy *policy) +{ + struct acpi_cpufreq_data *data = policy->driver_data; + + pr_debug("%s\n", __func__); + + data->resume = 1; + + return 0; +} + +static struct freq_attr *acpi_cpufreq_attr[] = { + &cpufreq_freq_attr_scaling_available_freqs, + &freqdomain_cpus, +#ifdef CONFIG_X86_ACPI_CPUFREQ_CPB + &cpb, +#endif + NULL, +}; + +static struct cpufreq_driver acpi_cpufreq_driver = { + .verify = cpufreq_generic_frequency_table_verify, + .target_index = acpi_cpufreq_target, + .fast_switch = acpi_cpufreq_fast_switch, + .bios_limit = acpi_processor_get_bios_limit, + .init = acpi_cpufreq_cpu_init, + .exit = acpi_cpufreq_cpu_exit, + .resume = acpi_cpufreq_resume, + .name = "acpi-cpufreq", + .attr = acpi_cpufreq_attr, +}; + +static void __init acpi_cpufreq_boost_init(void) +{ + if (!(boot_cpu_has(X86_FEATURE_CPB) || boot_cpu_has(X86_FEATURE_IDA))) { + pr_debug("Boost capabilities not present in the processor\n"); + return; + } + + acpi_cpufreq_driver.set_boost = set_boost; + acpi_cpufreq_driver.boost_enabled = boost_state(0); +} + +static int __init acpi_cpufreq_probe(struct platform_device *pdev) +{ + int ret; + + if (acpi_disabled) + return -ENODEV; + + /* don't keep reloading if cpufreq_driver exists */ + if (cpufreq_get_current_driver()) + return -ENODEV; + + pr_debug("%s\n", __func__); + + ret = acpi_cpufreq_early_init(); + if (ret) + return ret; + +#ifdef CONFIG_X86_ACPI_CPUFREQ_CPB + /* this is a sysfs file with a strange name and an even stranger + * semantic - per CPU instantiation, but system global effect. + * Lets enable it only on AMD CPUs for compatibility reasons and + * only if configured. This is considered legacy code, which + * will probably be removed at some point in the future. + */ + if (!check_amd_hwpstate_cpu(0)) { + struct freq_attr **attr; + + pr_debug("CPB unsupported, do not expose it\n"); + + for (attr = acpi_cpufreq_attr; *attr; attr++) + if (*attr == &cpb) { + *attr = NULL; + break; + } + } +#endif + acpi_cpufreq_boost_init(); + + ret = cpufreq_register_driver(&acpi_cpufreq_driver); + if (ret) { + free_acpi_perf_data(); + } + return ret; +} + +static void acpi_cpufreq_remove(struct platform_device *pdev) +{ + pr_debug("%s\n", __func__); + + cpufreq_unregister_driver(&acpi_cpufreq_driver); + + free_acpi_perf_data(); +} + +static struct platform_driver acpi_cpufreq_platdrv = { + .driver = { + .name = "acpi-cpufreq", + }, + .remove_new = acpi_cpufreq_remove, +}; + +static int __init acpi_cpufreq_init(void) +{ + return platform_driver_probe(&acpi_cpufreq_platdrv, acpi_cpufreq_probe); +} + +static void __exit acpi_cpufreq_exit(void) +{ + platform_driver_unregister(&acpi_cpufreq_platdrv); +} + +module_param(acpi_pstate_strict, uint, 0644); +MODULE_PARM_DESC(acpi_pstate_strict, + "value 0 or non-zero. non-zero -> strict ACPI checks are " + "performed during frequency changes."); + +late_initcall(acpi_cpufreq_init); +module_exit(acpi_cpufreq_exit); + +MODULE_ALIAS("platform:acpi-cpufreq"); |