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-rw-r--r--drivers/cpufreq/acpi-cpufreq.c773
1 files changed, 773 insertions, 0 deletions
diff --git a/drivers/cpufreq/acpi-cpufreq.c b/drivers/cpufreq/acpi-cpufreq.c
new file mode 100644
index 000000000000..4e04e1274388
--- /dev/null
+++ b/drivers/cpufreq/acpi-cpufreq.c
@@ -0,0 +1,773 @@
+/*
+ * 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>
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or (at
+ * your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ */
+
+#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/acpi.h>
+#include <linux/io.h>
+#include <linux/delay.h>
+#include <linux/uaccess.h>
+
+#include <acpi/processor.h>
+
+#include <asm/msr.h>
+#include <asm/processor.h>
+#include <asm/cpufeature.h>
+#include "mperf.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_IO_CAPABLE,
+};
+
+#define INTEL_MSR_RANGE (0xffff)
+
+struct acpi_cpufreq_data {
+ struct acpi_processor_performance *acpi_data;
+ struct cpufreq_frequency_table *freq_table;
+ unsigned int resume;
+ unsigned int cpu_feature;
+};
+
+static DEFINE_PER_CPU(struct acpi_cpufreq_data *, acfreq_data);
+
+/* acpi_perf_data is a pointer to percpu data. */
+static struct acpi_processor_performance __percpu *acpi_perf_data;
+
+static struct cpufreq_driver acpi_cpufreq_driver;
+
+static unsigned int acpi_pstate_strict;
+
+static int check_est_cpu(unsigned int cpuid)
+{
+ struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
+
+ return cpu_has(cpu, X86_FEATURE_EST);
+}
+
+static unsigned extract_io(u32 value, struct acpi_cpufreq_data *data)
+{
+ struct acpi_processor_performance *perf;
+ int i;
+
+ perf = data->acpi_data;
+
+ for (i = 0; i < perf->state_count; i++) {
+ if (value == perf->states[i].status)
+ return data->freq_table[i].frequency;
+ }
+ return 0;
+}
+
+static unsigned extract_msr(u32 msr, struct acpi_cpufreq_data *data)
+{
+ int i;
+ struct acpi_processor_performance *perf;
+
+ msr &= INTEL_MSR_RANGE;
+ perf = data->acpi_data;
+
+ for (i = 0; data->freq_table[i].frequency != CPUFREQ_TABLE_END; i++) {
+ if (msr == perf->states[data->freq_table[i].index].status)
+ return data->freq_table[i].frequency;
+ }
+ return data->freq_table[0].frequency;
+}
+
+static unsigned extract_freq(u32 val, struct acpi_cpufreq_data *data)
+{
+ switch (data->cpu_feature) {
+ case SYSTEM_INTEL_MSR_CAPABLE:
+ return extract_msr(val, data);
+ case SYSTEM_IO_CAPABLE:
+ return extract_io(val, data);
+ default:
+ return 0;
+ }
+}
+
+struct msr_addr {
+ u32 reg;
+};
+
+struct io_addr {
+ u16 port;
+ u8 bit_width;
+};
+
+struct drv_cmd {
+ unsigned int type;
+ const struct cpumask *mask;
+ union {
+ struct msr_addr msr;
+ struct io_addr io;
+ } addr;
+ u32 val;
+};
+
+/* Called via smp_call_function_single(), on the target CPU */
+static void do_drv_read(void *_cmd)
+{
+ struct drv_cmd *cmd = _cmd;
+ u32 h;
+
+ switch (cmd->type) {
+ case SYSTEM_INTEL_MSR_CAPABLE:
+ rdmsr(cmd->addr.msr.reg, cmd->val, h);
+ break;
+ case SYSTEM_IO_CAPABLE:
+ acpi_os_read_port((acpi_io_address)cmd->addr.io.port,
+ &cmd->val,
+ (u32)cmd->addr.io.bit_width);
+ break;
+ default:
+ break;
+ }
+}
+
+/* Called via smp_call_function_many(), on the target CPUs */
+static void do_drv_write(void *_cmd)
+{
+ struct drv_cmd *cmd = _cmd;
+ u32 lo, hi;
+
+ switch (cmd->type) {
+ case SYSTEM_INTEL_MSR_CAPABLE:
+ rdmsr(cmd->addr.msr.reg, lo, hi);
+ lo = (lo & ~INTEL_MSR_RANGE) | (cmd->val & INTEL_MSR_RANGE);
+ wrmsr(cmd->addr.msr.reg, lo, hi);
+ break;
+ case SYSTEM_IO_CAPABLE:
+ acpi_os_write_port((acpi_io_address)cmd->addr.io.port,
+ cmd->val,
+ (u32)cmd->addr.io.bit_width);
+ break;
+ default:
+ break;
+ }
+}
+
+static void drv_read(struct drv_cmd *cmd)
+{
+ int err;
+ cmd->val = 0;
+
+ err = smp_call_function_any(cmd->mask, do_drv_read, cmd, 1);
+ WARN_ON_ONCE(err); /* smp_call_function_any() was buggy? */
+}
+
+static void drv_write(struct drv_cmd *cmd)
+{
+ int this_cpu;
+
+ this_cpu = get_cpu();
+ if (cpumask_test_cpu(this_cpu, cmd->mask))
+ do_drv_write(cmd);
+ smp_call_function_many(cmd->mask, do_drv_write, cmd, 1);
+ put_cpu();
+}
+
+static u32 get_cur_val(const struct cpumask *mask)
+{
+ struct acpi_processor_performance *perf;
+ struct drv_cmd cmd;
+
+ if (unlikely(cpumask_empty(mask)))
+ return 0;
+
+ switch (per_cpu(acfreq_data, cpumask_first(mask))->cpu_feature) {
+ case SYSTEM_INTEL_MSR_CAPABLE:
+ cmd.type = SYSTEM_INTEL_MSR_CAPABLE;
+ cmd.addr.msr.reg = MSR_IA32_PERF_STATUS;
+ break;
+ case SYSTEM_IO_CAPABLE:
+ cmd.type = SYSTEM_IO_CAPABLE;
+ perf = per_cpu(acfreq_data, cpumask_first(mask))->acpi_data;
+ cmd.addr.io.port = perf->control_register.address;
+ cmd.addr.io.bit_width = perf->control_register.bit_width;
+ break;
+ default:
+ return 0;
+ }
+
+ cmd.mask = mask;
+ drv_read(&cmd);
+
+ pr_debug("get_cur_val = %u\n", cmd.val);
+
+ return cmd.val;
+}
+
+static unsigned int get_cur_freq_on_cpu(unsigned int cpu)
+{
+ struct acpi_cpufreq_data *data = per_cpu(acfreq_data, cpu);
+ unsigned int freq;
+ unsigned int cached_freq;
+
+ pr_debug("get_cur_freq_on_cpu (%d)\n", cpu);
+
+ if (unlikely(data == NULL ||
+ data->acpi_data == NULL || data->freq_table == NULL)) {
+ return 0;
+ }
+
+ cached_freq = data->freq_table[data->acpi_data->state].frequency;
+ freq = extract_freq(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(const struct cpumask *mask, unsigned int freq,
+ struct acpi_cpufreq_data *data)
+{
+ unsigned int cur_freq;
+ unsigned int i;
+
+ for (i = 0; i < 100; i++) {
+ cur_freq = extract_freq(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 target_freq, unsigned int relation)
+{
+ struct acpi_cpufreq_data *data = per_cpu(acfreq_data, policy->cpu);
+ struct acpi_processor_performance *perf;
+ struct cpufreq_freqs freqs;
+ struct drv_cmd cmd;
+ unsigned int next_state = 0; /* Index into freq_table */
+ unsigned int next_perf_state = 0; /* Index into perf table */
+ unsigned int i;
+ int result = 0;
+
+ pr_debug("acpi_cpufreq_target %d (%d)\n", target_freq, policy->cpu);
+
+ if (unlikely(data == NULL ||
+ data->acpi_data == NULL || data->freq_table == NULL)) {
+ return -ENODEV;
+ }
+
+ perf = data->acpi_data;
+ result = cpufreq_frequency_table_target(policy,
+ data->freq_table,
+ target_freq,
+ relation, &next_state);
+ if (unlikely(result)) {
+ result = -ENODEV;
+ goto out;
+ }
+
+ next_perf_state = data->freq_table[next_state].index;
+ 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);
+ goto out;
+ }
+ }
+
+ switch (data->cpu_feature) {
+ case SYSTEM_INTEL_MSR_CAPABLE:
+ cmd.type = SYSTEM_INTEL_MSR_CAPABLE;
+ cmd.addr.msr.reg = MSR_IA32_PERF_CTL;
+ cmd.val = (u32) perf->states[next_perf_state].control;
+ break;
+ case SYSTEM_IO_CAPABLE:
+ cmd.type = SYSTEM_IO_CAPABLE;
+ cmd.addr.io.port = perf->control_register.address;
+ cmd.addr.io.bit_width = perf->control_register.bit_width;
+ cmd.val = (u32) perf->states[next_perf_state].control;
+ break;
+ default:
+ result = -ENODEV;
+ goto out;
+ }
+
+ /* cpufreq holds the hotplug lock, so we are safe from here on */
+ if (policy->shared_type != CPUFREQ_SHARED_TYPE_ANY)
+ cmd.mask = policy->cpus;
+ else
+ cmd.mask = cpumask_of(policy->cpu);
+
+ freqs.old = perf->states[perf->state].core_frequency * 1000;
+ freqs.new = data->freq_table[next_state].frequency;
+ for_each_cpu(i, policy->cpus) {
+ freqs.cpu = i;
+ cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
+ }
+
+ drv_write(&cmd);
+
+ if (acpi_pstate_strict) {
+ if (!check_freqs(cmd.mask, freqs.new, data)) {
+ pr_debug("acpi_cpufreq_target failed (%d)\n",
+ policy->cpu);
+ result = -EAGAIN;
+ goto out;
+ }
+ }
+
+ for_each_cpu(i, policy->cpus) {
+ freqs.cpu = i;
+ cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
+ }
+ perf->state = next_perf_state;
+
+out:
+ return result;
+}
+
+static int acpi_cpufreq_verify(struct cpufreq_policy *policy)
+{
+ struct acpi_cpufreq_data *data = per_cpu(acfreq_data, policy->cpu);
+
+ pr_debug("acpi_cpufreq_verify\n");
+
+ return cpufreq_frequency_table_verify(policy, data->freq_table);
+}
+
+static unsigned long
+acpi_cpufreq_guess_freq(struct acpi_cpufreq_data *data, unsigned int cpu)
+{
+ struct acpi_processor_performance *perf = data->acpi_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);
+}
+
+/*
+ * 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("acpi_cpufreq_early_init\n");
+
+ 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
+ * http://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_mask == 8)) {
+ printk(KERN_INFO "acpi-cpufreq: Intel(R) "
+ "Xeon(R) 7100 Errata AL30, processors may "
+ "lock up on frequency changes: disabling "
+ "acpi-cpufreq.\n");
+ return -ENODEV;
+ }
+ }
+ return 0;
+}
+#endif
+
+static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
+{
+ unsigned int i;
+ unsigned int valid_states = 0;
+ unsigned int cpu = policy->cpu;
+ struct acpi_cpufreq_data *data;
+ unsigned int result = 0;
+ struct cpuinfo_x86 *c = &cpu_data(policy->cpu);
+ struct acpi_processor_performance *perf;
+#ifdef CONFIG_SMP
+ static int blacklisted;
+#endif
+
+ pr_debug("acpi_cpufreq_cpu_init\n");
+
+#ifdef CONFIG_SMP
+ if (blacklisted)
+ return blacklisted;
+ blacklisted = acpi_cpufreq_blacklist(c);
+ if (blacklisted)
+ return blacklisted;
+#endif
+
+ data = kzalloc(sizeof(struct acpi_cpufreq_data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ data->acpi_data = per_cpu_ptr(acpi_perf_data, cpu);
+ per_cpu(acfreq_data, cpu) = data;
+
+ if (cpu_has(c, X86_FEATURE_CONSTANT_TSC))
+ acpi_cpufreq_driver.flags |= CPUFREQ_CONST_LOOPS;
+
+ result = acpi_processor_register_performance(data->acpi_data, cpu);
+ if (result)
+ goto err_free;
+
+ perf = data->acpi_data;
+ 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(policy->related_cpus, perf->shared_cpu_map);
+
+#ifdef CONFIG_SMP
+ dmi_check_system(sw_any_bug_dmi_table);
+ if (bios_with_sw_any_bug && cpumask_weight(policy->cpus) == 1) {
+ policy->shared_type = CPUFREQ_SHARED_TYPE_ALL;
+ cpumask_copy(policy->cpus, cpu_core_mask(cpu));
+ }
+#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:
+ pr_debug("SYSTEM IO addr space\n");
+ data->cpu_feature = SYSTEM_IO_CAPABLE;
+ break;
+ case ACPI_ADR_SPACE_FIXED_HARDWARE:
+ pr_debug("HARDWARE addr space\n");
+ if (!check_est_cpu(cpu)) {
+ result = -ENODEV;
+ goto err_unreg;
+ }
+ data->cpu_feature = SYSTEM_INTEL_MSR_CAPABLE;
+ break;
+ default:
+ pr_debug("Unknown addr space %d\n",
+ (u32) (perf->control_register.space_id));
+ result = -ENODEV;
+ goto err_unreg;
+ }
+
+ data->freq_table = kmalloc(sizeof(struct cpufreq_frequency_table) *
+ (perf->state_count+1), GFP_KERNEL);
+ if (!data->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;
+ printk_once(KERN_INFO
+ "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 >=
+ data->freq_table[valid_states-1].frequency / 1000)
+ continue;
+
+ data->freq_table[valid_states].index = i;
+ data->freq_table[valid_states].frequency =
+ perf->states[i].core_frequency * 1000;
+ valid_states++;
+ }
+ data->freq_table[valid_states].frequency = CPUFREQ_TABLE_END;
+ perf->state = 0;
+
+ result = cpufreq_frequency_table_cpuinfo(policy, data->freq_table);
+ if (result)
+ goto err_freqfree;
+
+ if (perf->states[0].core_frequency * 1000 != policy->cpuinfo.max_freq)
+ printk(KERN_WARNING FW_WARN "P-state 0 is not max freq\n");
+
+ switch (perf->control_register.space_id) {
+ case ACPI_ADR_SPACE_SYSTEM_IO:
+ /* Current speed is unknown and not detectable by IO port */
+ 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;
+ policy->cur = get_cur_freq_on_cpu(cpu);
+ break;
+ default:
+ break;
+ }
+
+ /* notify BIOS that we exist */
+ acpi_processor_notify_smm(THIS_MODULE);
+
+ /* Check for APERF/MPERF support in hardware */
+ if (cpu_has(c, X86_FEATURE_APERFMPERF))
+ acpi_cpufreq_driver.getavg = cpufreq_get_measured_perf;
+
+ 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);
+
+ cpufreq_frequency_table_get_attr(data->freq_table, policy->cpu);
+
+ /*
+ * the first call to ->target() should result in us actually
+ * writing something to the appropriate registers.
+ */
+ data->resume = 1;
+
+ return result;
+
+err_freqfree:
+ kfree(data->freq_table);
+err_unreg:
+ acpi_processor_unregister_performance(perf, cpu);
+err_free:
+ kfree(data);
+ per_cpu(acfreq_data, cpu) = NULL;
+
+ return result;
+}
+
+static int acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy)
+{
+ struct acpi_cpufreq_data *data = per_cpu(acfreq_data, policy->cpu);
+
+ pr_debug("acpi_cpufreq_cpu_exit\n");
+
+ if (data) {
+ cpufreq_frequency_table_put_attr(policy->cpu);
+ per_cpu(acfreq_data, policy->cpu) = NULL;
+ acpi_processor_unregister_performance(data->acpi_data,
+ policy->cpu);
+ kfree(data->freq_table);
+ kfree(data);
+ }
+
+ return 0;
+}
+
+static int acpi_cpufreq_resume(struct cpufreq_policy *policy)
+{
+ struct acpi_cpufreq_data *data = per_cpu(acfreq_data, policy->cpu);
+
+ pr_debug("acpi_cpufreq_resume\n");
+
+ data->resume = 1;
+
+ return 0;
+}
+
+static struct freq_attr *acpi_cpufreq_attr[] = {
+ &cpufreq_freq_attr_scaling_available_freqs,
+ NULL,
+};
+
+static struct cpufreq_driver acpi_cpufreq_driver = {
+ .verify = acpi_cpufreq_verify,
+ .target = acpi_cpufreq_target,
+ .bios_limit = acpi_processor_get_bios_limit,
+ .init = acpi_cpufreq_cpu_init,
+ .exit = acpi_cpufreq_cpu_exit,
+ .resume = acpi_cpufreq_resume,
+ .name = "acpi-cpufreq",
+ .owner = THIS_MODULE,
+ .attr = acpi_cpufreq_attr,
+};
+
+static int __init acpi_cpufreq_init(void)
+{
+ int ret;
+
+ if (acpi_disabled)
+ return 0;
+
+ pr_debug("acpi_cpufreq_init\n");
+
+ ret = acpi_cpufreq_early_init();
+ if (ret)
+ return ret;
+
+ ret = cpufreq_register_driver(&acpi_cpufreq_driver);
+ if (ret)
+ free_acpi_perf_data();
+
+ return ret;
+}
+
+static void __exit acpi_cpufreq_exit(void)
+{
+ pr_debug("acpi_cpufreq_exit\n");
+
+ cpufreq_unregister_driver(&acpi_cpufreq_driver);
+
+ free_percpu(acpi_perf_data);
+}
+
+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("acpi");