diff options
Diffstat (limited to 'drivers/cpufreq/intel_pstate.c')
-rw-r--r-- | drivers/cpufreq/intel_pstate.c | 823 |
1 files changed, 823 insertions, 0 deletions
diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c new file mode 100644 index 00000000000..096fde0ebcb --- /dev/null +++ b/drivers/cpufreq/intel_pstate.c @@ -0,0 +1,823 @@ +/* + * cpufreq_snb.c: Native P state management for Intel processors + * + * (C) Copyright 2012 Intel Corporation + * Author: Dirk Brandewie <dirk.j.brandewie@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; version 2 + * of the License. + */ + +#include <linux/kernel.h> +#include <linux/kernel_stat.h> +#include <linux/module.h> +#include <linux/ktime.h> +#include <linux/hrtimer.h> +#include <linux/tick.h> +#include <linux/slab.h> +#include <linux/sched.h> +#include <linux/list.h> +#include <linux/cpu.h> +#include <linux/cpufreq.h> +#include <linux/sysfs.h> +#include <linux/types.h> +#include <linux/fs.h> +#include <linux/debugfs.h> +#include <trace/events/power.h> + +#include <asm/div64.h> +#include <asm/msr.h> +#include <asm/cpu_device_id.h> + +#define SAMPLE_COUNT 3 + +#define FRAC_BITS 8 +#define int_tofp(X) ((int64_t)(X) << FRAC_BITS) +#define fp_toint(X) ((X) >> FRAC_BITS) + +static inline int32_t mul_fp(int32_t x, int32_t y) +{ + return ((int64_t)x * (int64_t)y) >> FRAC_BITS; +} + +static inline int32_t div_fp(int32_t x, int32_t y) +{ + return div_s64((int64_t)x << FRAC_BITS, (int64_t)y); +} + +struct sample { + ktime_t start_time; + ktime_t end_time; + int core_pct_busy; + int pstate_pct_busy; + u64 duration_us; + u64 idletime_us; + u64 aperf; + u64 mperf; + int freq; +}; + +struct pstate_data { + int current_pstate; + int min_pstate; + int max_pstate; + int turbo_pstate; +}; + +struct _pid { + int setpoint; + int32_t integral; + int32_t p_gain; + int32_t i_gain; + int32_t d_gain; + int deadband; + int last_err; +}; + +struct cpudata { + int cpu; + + char name[64]; + + struct timer_list timer; + + struct pstate_adjust_policy *pstate_policy; + struct pstate_data pstate; + struct _pid pid; + struct _pid idle_pid; + + int min_pstate_count; + int idle_mode; + + ktime_t prev_sample; + u64 prev_idle_time_us; + u64 prev_aperf; + u64 prev_mperf; + int sample_ptr; + struct sample samples[SAMPLE_COUNT]; +}; + +static struct cpudata **all_cpu_data; +struct pstate_adjust_policy { + int sample_rate_ms; + int deadband; + int setpoint; + int p_gain_pct; + int d_gain_pct; + int i_gain_pct; +}; + +static struct pstate_adjust_policy default_policy = { + .sample_rate_ms = 10, + .deadband = 0, + .setpoint = 109, + .p_gain_pct = 17, + .d_gain_pct = 0, + .i_gain_pct = 4, +}; + +struct perf_limits { + int no_turbo; + int max_perf_pct; + int min_perf_pct; + int32_t max_perf; + int32_t min_perf; +}; + +static struct perf_limits limits = { + .no_turbo = 0, + .max_perf_pct = 100, + .max_perf = int_tofp(1), + .min_perf_pct = 0, + .min_perf = 0, +}; + +static inline void pid_reset(struct _pid *pid, int setpoint, int busy, + int deadband, int integral) { + pid->setpoint = setpoint; + pid->deadband = deadband; + pid->integral = int_tofp(integral); + pid->last_err = setpoint - busy; +} + +static inline void pid_p_gain_set(struct _pid *pid, int percent) +{ + pid->p_gain = div_fp(int_tofp(percent), int_tofp(100)); +} + +static inline void pid_i_gain_set(struct _pid *pid, int percent) +{ + pid->i_gain = div_fp(int_tofp(percent), int_tofp(100)); +} + +static inline void pid_d_gain_set(struct _pid *pid, int percent) +{ + + pid->d_gain = div_fp(int_tofp(percent), int_tofp(100)); +} + +static signed int pid_calc(struct _pid *pid, int busy) +{ + signed int err, result; + int32_t pterm, dterm, fp_error; + int32_t integral_limit; + + err = pid->setpoint - busy; + fp_error = int_tofp(err); + + if (abs(err) <= pid->deadband) + return 0; + + pterm = mul_fp(pid->p_gain, fp_error); + + pid->integral += fp_error; + + /* limit the integral term */ + integral_limit = int_tofp(30); + if (pid->integral > integral_limit) + pid->integral = integral_limit; + if (pid->integral < -integral_limit) + pid->integral = -integral_limit; + + dterm = mul_fp(pid->d_gain, (err - pid->last_err)); + pid->last_err = err; + + result = pterm + mul_fp(pid->integral, pid->i_gain) + dterm; + + return (signed int)fp_toint(result); +} + +static inline void intel_pstate_busy_pid_reset(struct cpudata *cpu) +{ + pid_p_gain_set(&cpu->pid, cpu->pstate_policy->p_gain_pct); + pid_d_gain_set(&cpu->pid, cpu->pstate_policy->d_gain_pct); + pid_i_gain_set(&cpu->pid, cpu->pstate_policy->i_gain_pct); + + pid_reset(&cpu->pid, + cpu->pstate_policy->setpoint, + 100, + cpu->pstate_policy->deadband, + 0); +} + +static inline void intel_pstate_idle_pid_reset(struct cpudata *cpu) +{ + pid_p_gain_set(&cpu->idle_pid, cpu->pstate_policy->p_gain_pct); + pid_d_gain_set(&cpu->idle_pid, cpu->pstate_policy->d_gain_pct); + pid_i_gain_set(&cpu->idle_pid, cpu->pstate_policy->i_gain_pct); + + pid_reset(&cpu->idle_pid, + 75, + 50, + cpu->pstate_policy->deadband, + 0); +} + +static inline void intel_pstate_reset_all_pid(void) +{ + unsigned int cpu; + for_each_online_cpu(cpu) { + if (all_cpu_data[cpu]) + intel_pstate_busy_pid_reset(all_cpu_data[cpu]); + } +} + +/************************** debugfs begin ************************/ +static int pid_param_set(void *data, u64 val) +{ + *(u32 *)data = val; + intel_pstate_reset_all_pid(); + return 0; +} +static int pid_param_get(void *data, u64 *val) +{ + *val = *(u32 *)data; + return 0; +} +DEFINE_SIMPLE_ATTRIBUTE(fops_pid_param, pid_param_get, + pid_param_set, "%llu\n"); + +struct pid_param { + char *name; + void *value; +}; + +static struct pid_param pid_files[] = { + {"sample_rate_ms", &default_policy.sample_rate_ms}, + {"d_gain_pct", &default_policy.d_gain_pct}, + {"i_gain_pct", &default_policy.i_gain_pct}, + {"deadband", &default_policy.deadband}, + {"setpoint", &default_policy.setpoint}, + {"p_gain_pct", &default_policy.p_gain_pct}, + {NULL, NULL} +}; + +static struct dentry *debugfs_parent; +static void intel_pstate_debug_expose_params(void) +{ + int i = 0; + + debugfs_parent = debugfs_create_dir("pstate_snb", NULL); + if (IS_ERR_OR_NULL(debugfs_parent)) + return; + while (pid_files[i].name) { + debugfs_create_file(pid_files[i].name, 0660, + debugfs_parent, pid_files[i].value, + &fops_pid_param); + i++; + } +} + +/************************** debugfs end ************************/ + +/************************** sysfs begin ************************/ +#define show_one(file_name, object) \ + static ssize_t show_##file_name \ + (struct kobject *kobj, struct attribute *attr, char *buf) \ + { \ + return sprintf(buf, "%u\n", limits.object); \ + } + +static ssize_t store_no_turbo(struct kobject *a, struct attribute *b, + const char *buf, size_t count) +{ + unsigned int input; + int ret; + ret = sscanf(buf, "%u", &input); + if (ret != 1) + return -EINVAL; + limits.no_turbo = clamp_t(int, input, 0 , 1); + + return count; +} + +static ssize_t store_max_perf_pct(struct kobject *a, struct attribute *b, + const char *buf, size_t count) +{ + unsigned int input; + int ret; + ret = sscanf(buf, "%u", &input); + if (ret != 1) + return -EINVAL; + + limits.max_perf_pct = clamp_t(int, input, 0 , 100); + limits.max_perf = div_fp(int_tofp(limits.max_perf_pct), int_tofp(100)); + return count; +} + +static ssize_t store_min_perf_pct(struct kobject *a, struct attribute *b, + const char *buf, size_t count) +{ + unsigned int input; + int ret; + ret = sscanf(buf, "%u", &input); + if (ret != 1) + return -EINVAL; + limits.min_perf_pct = clamp_t(int, input, 0 , 100); + limits.min_perf = div_fp(int_tofp(limits.min_perf_pct), int_tofp(100)); + + return count; +} + +show_one(no_turbo, no_turbo); +show_one(max_perf_pct, max_perf_pct); +show_one(min_perf_pct, min_perf_pct); + +define_one_global_rw(no_turbo); +define_one_global_rw(max_perf_pct); +define_one_global_rw(min_perf_pct); + +static struct attribute *intel_pstate_attributes[] = { + &no_turbo.attr, + &max_perf_pct.attr, + &min_perf_pct.attr, + NULL +}; + +static struct attribute_group intel_pstate_attr_group = { + .attrs = intel_pstate_attributes, +}; +static struct kobject *intel_pstate_kobject; + +static void intel_pstate_sysfs_expose_params(void) +{ + int rc; + + intel_pstate_kobject = kobject_create_and_add("intel_pstate", + &cpu_subsys.dev_root->kobj); + BUG_ON(!intel_pstate_kobject); + rc = sysfs_create_group(intel_pstate_kobject, + &intel_pstate_attr_group); + BUG_ON(rc); +} + +/************************** sysfs end ************************/ + +static int intel_pstate_min_pstate(void) +{ + u64 value; + rdmsrl(0xCE, value); + return (value >> 40) & 0xFF; +} + +static int intel_pstate_max_pstate(void) +{ + u64 value; + rdmsrl(0xCE, value); + return (value >> 8) & 0xFF; +} + +static int intel_pstate_turbo_pstate(void) +{ + u64 value; + int nont, ret; + rdmsrl(0x1AD, value); + nont = intel_pstate_max_pstate(); + ret = ((value) & 255); + if (ret <= nont) + ret = nont; + return ret; +} + +static void intel_pstate_get_min_max(struct cpudata *cpu, int *min, int *max) +{ + int max_perf = cpu->pstate.turbo_pstate; + int min_perf; + if (limits.no_turbo) + max_perf = cpu->pstate.max_pstate; + + max_perf = fp_toint(mul_fp(int_tofp(max_perf), limits.max_perf)); + *max = clamp_t(int, max_perf, + cpu->pstate.min_pstate, cpu->pstate.turbo_pstate); + + min_perf = fp_toint(mul_fp(int_tofp(max_perf), limits.min_perf)); + *min = clamp_t(int, min_perf, + cpu->pstate.min_pstate, max_perf); +} + +static void intel_pstate_set_pstate(struct cpudata *cpu, int pstate) +{ + int max_perf, min_perf; + + intel_pstate_get_min_max(cpu, &min_perf, &max_perf); + + pstate = clamp_t(int, pstate, min_perf, max_perf); + + if (pstate == cpu->pstate.current_pstate) + return; + +#ifndef MODULE + trace_cpu_frequency(pstate * 100000, cpu->cpu); +#endif + cpu->pstate.current_pstate = pstate; + wrmsrl(MSR_IA32_PERF_CTL, pstate << 8); + +} + +static inline void intel_pstate_pstate_increase(struct cpudata *cpu, int steps) +{ + int target; + target = cpu->pstate.current_pstate + steps; + + intel_pstate_set_pstate(cpu, target); +} + +static inline void intel_pstate_pstate_decrease(struct cpudata *cpu, int steps) +{ + int target; + target = cpu->pstate.current_pstate - steps; + intel_pstate_set_pstate(cpu, target); +} + +static void intel_pstate_get_cpu_pstates(struct cpudata *cpu) +{ + sprintf(cpu->name, "Intel 2nd generation core"); + + cpu->pstate.min_pstate = intel_pstate_min_pstate(); + cpu->pstate.max_pstate = intel_pstate_max_pstate(); + cpu->pstate.turbo_pstate = intel_pstate_turbo_pstate(); + + /* + * goto max pstate so we don't slow up boot if we are built-in if we are + * a module we will take care of it during normal operation + */ + intel_pstate_set_pstate(cpu, cpu->pstate.max_pstate); +} + +static inline void intel_pstate_calc_busy(struct cpudata *cpu, + struct sample *sample) +{ + u64 core_pct; + sample->pstate_pct_busy = 100 - div64_u64( + sample->idletime_us * 100, + sample->duration_us); + core_pct = div64_u64(sample->aperf * 100, sample->mperf); + sample->freq = cpu->pstate.turbo_pstate * core_pct * 1000; + + sample->core_pct_busy = div_s64((sample->pstate_pct_busy * core_pct), + 100); +} + +static inline void intel_pstate_sample(struct cpudata *cpu) +{ + ktime_t now; + u64 idle_time_us; + u64 aperf, mperf; + + now = ktime_get(); + idle_time_us = get_cpu_idle_time_us(cpu->cpu, NULL); + + rdmsrl(MSR_IA32_APERF, aperf); + rdmsrl(MSR_IA32_MPERF, mperf); + /* for the first sample, don't actually record a sample, just + * set the baseline */ + if (cpu->prev_idle_time_us > 0) { + cpu->sample_ptr = (cpu->sample_ptr + 1) % SAMPLE_COUNT; + cpu->samples[cpu->sample_ptr].start_time = cpu->prev_sample; + cpu->samples[cpu->sample_ptr].end_time = now; + cpu->samples[cpu->sample_ptr].duration_us = + ktime_us_delta(now, cpu->prev_sample); + cpu->samples[cpu->sample_ptr].idletime_us = + idle_time_us - cpu->prev_idle_time_us; + + cpu->samples[cpu->sample_ptr].aperf = aperf; + cpu->samples[cpu->sample_ptr].mperf = mperf; + cpu->samples[cpu->sample_ptr].aperf -= cpu->prev_aperf; + cpu->samples[cpu->sample_ptr].mperf -= cpu->prev_mperf; + + intel_pstate_calc_busy(cpu, &cpu->samples[cpu->sample_ptr]); + } + + cpu->prev_sample = now; + cpu->prev_idle_time_us = idle_time_us; + cpu->prev_aperf = aperf; + cpu->prev_mperf = mperf; +} + +static inline void intel_pstate_set_sample_time(struct cpudata *cpu) +{ + int sample_time, delay; + + sample_time = cpu->pstate_policy->sample_rate_ms; + delay = msecs_to_jiffies(sample_time); + delay -= jiffies % delay; + mod_timer_pinned(&cpu->timer, jiffies + delay); +} + +static inline void intel_pstate_idle_mode(struct cpudata *cpu) +{ + cpu->idle_mode = 1; +} + +static inline void intel_pstate_normal_mode(struct cpudata *cpu) +{ + cpu->idle_mode = 0; +} + +static inline int intel_pstate_get_scaled_busy(struct cpudata *cpu) +{ + int32_t busy_scaled; + int32_t core_busy, turbo_pstate, current_pstate; + + core_busy = int_tofp(cpu->samples[cpu->sample_ptr].core_pct_busy); + turbo_pstate = int_tofp(cpu->pstate.turbo_pstate); + current_pstate = int_tofp(cpu->pstate.current_pstate); + busy_scaled = mul_fp(core_busy, div_fp(turbo_pstate, current_pstate)); + + return fp_toint(busy_scaled); +} + +static inline void intel_pstate_adjust_busy_pstate(struct cpudata *cpu) +{ + int busy_scaled; + struct _pid *pid; + signed int ctl = 0; + int steps; + + pid = &cpu->pid; + busy_scaled = intel_pstate_get_scaled_busy(cpu); + + ctl = pid_calc(pid, busy_scaled); + + steps = abs(ctl); + if (ctl < 0) + intel_pstate_pstate_increase(cpu, steps); + else + intel_pstate_pstate_decrease(cpu, steps); +} + +static inline void intel_pstate_adjust_idle_pstate(struct cpudata *cpu) +{ + int busy_scaled; + struct _pid *pid; + int ctl = 0; + int steps; + + pid = &cpu->idle_pid; + + busy_scaled = intel_pstate_get_scaled_busy(cpu); + + ctl = pid_calc(pid, 100 - busy_scaled); + + steps = abs(ctl); + if (ctl < 0) + intel_pstate_pstate_decrease(cpu, steps); + else + intel_pstate_pstate_increase(cpu, steps); + + if (cpu->pstate.current_pstate == cpu->pstate.min_pstate) + intel_pstate_normal_mode(cpu); +} + +static void intel_pstate_timer_func(unsigned long __data) +{ + struct cpudata *cpu = (struct cpudata *) __data; + + intel_pstate_sample(cpu); + + if (!cpu->idle_mode) + intel_pstate_adjust_busy_pstate(cpu); + else + intel_pstate_adjust_idle_pstate(cpu); + +#if defined(XPERF_FIX) + if (cpu->pstate.current_pstate == cpu->pstate.min_pstate) { + cpu->min_pstate_count++; + if (!(cpu->min_pstate_count % 5)) { + intel_pstate_set_pstate(cpu, cpu->pstate.max_pstate); + intel_pstate_idle_mode(cpu); + } + } else + cpu->min_pstate_count = 0; +#endif + intel_pstate_set_sample_time(cpu); +} + +#define ICPU(model, policy) \ + { X86_VENDOR_INTEL, 6, model, X86_FEATURE_ANY, (unsigned long)&policy } + +static const struct x86_cpu_id intel_pstate_cpu_ids[] = { + ICPU(0x2a, default_policy), + ICPU(0x2d, default_policy), + {} +}; +MODULE_DEVICE_TABLE(x86cpu, intel_pstate_cpu_ids); + +static int intel_pstate_init_cpu(unsigned int cpunum) +{ + + const struct x86_cpu_id *id; + struct cpudata *cpu; + + id = x86_match_cpu(intel_pstate_cpu_ids); + if (!id) + return -ENODEV; + + all_cpu_data[cpunum] = kzalloc(sizeof(struct cpudata), GFP_KERNEL); + if (!all_cpu_data[cpunum]) + return -ENOMEM; + + cpu = all_cpu_data[cpunum]; + + intel_pstate_get_cpu_pstates(cpu); + + cpu->cpu = cpunum; + cpu->pstate_policy = + (struct pstate_adjust_policy *)id->driver_data; + init_timer_deferrable(&cpu->timer); + cpu->timer.function = intel_pstate_timer_func; + cpu->timer.data = + (unsigned long)cpu; + cpu->timer.expires = jiffies + HZ/100; + intel_pstate_busy_pid_reset(cpu); + intel_pstate_idle_pid_reset(cpu); + intel_pstate_sample(cpu); + intel_pstate_set_pstate(cpu, cpu->pstate.max_pstate); + + add_timer_on(&cpu->timer, cpunum); + + pr_info("Intel pstate controlling: cpu %d\n", cpunum); + + return 0; +} + +static unsigned int intel_pstate_get(unsigned int cpu_num) +{ + struct sample *sample; + struct cpudata *cpu; + + cpu = all_cpu_data[cpu_num]; + if (!cpu) + return 0; + sample = &cpu->samples[cpu->sample_ptr]; + return sample->freq; +} + +static int intel_pstate_set_policy(struct cpufreq_policy *policy) +{ + struct cpudata *cpu; + int min, max; + + cpu = all_cpu_data[policy->cpu]; + + intel_pstate_get_min_max(cpu, &min, &max); + + limits.min_perf_pct = (policy->min * 100) / policy->cpuinfo.max_freq; + limits.min_perf_pct = clamp_t(int, limits.min_perf_pct, 0 , 100); + limits.min_perf = div_fp(int_tofp(limits.min_perf_pct), int_tofp(100)); + + limits.max_perf_pct = policy->max * 100 / policy->cpuinfo.max_freq; + limits.max_perf_pct = clamp_t(int, limits.max_perf_pct, 0 , 100); + limits.max_perf = div_fp(int_tofp(limits.max_perf_pct), int_tofp(100)); + + if (policy->policy == CPUFREQ_POLICY_PERFORMANCE) { + limits.min_perf_pct = 100; + limits.min_perf = int_tofp(1); + limits.max_perf_pct = 100; + limits.max_perf = int_tofp(1); + limits.no_turbo = 0; + } + + return 0; +} + +static int intel_pstate_verify_policy(struct cpufreq_policy *policy) +{ + cpufreq_verify_within_limits(policy, + policy->cpuinfo.min_freq, + policy->cpuinfo.max_freq); + + if ((policy->policy != CPUFREQ_POLICY_POWERSAVE) && + (policy->policy != CPUFREQ_POLICY_PERFORMANCE)) + return -EINVAL; + + return 0; +} + +static int __cpuinit intel_pstate_cpu_exit(struct cpufreq_policy *policy) +{ + int cpu = policy->cpu; + + del_timer(&all_cpu_data[cpu]->timer); + kfree(all_cpu_data[cpu]); + all_cpu_data[cpu] = NULL; + return 0; +} + +static int __cpuinit intel_pstate_cpu_init(struct cpufreq_policy *policy) +{ + int rc, min_pstate, max_pstate; + struct cpudata *cpu; + + rc = intel_pstate_init_cpu(policy->cpu); + if (rc) + return rc; + + cpu = all_cpu_data[policy->cpu]; + + if (!limits.no_turbo && + limits.min_perf_pct == 100 && limits.max_perf_pct == 100) + policy->policy = CPUFREQ_POLICY_PERFORMANCE; + else + policy->policy = CPUFREQ_POLICY_POWERSAVE; + + intel_pstate_get_min_max(cpu, &min_pstate, &max_pstate); + policy->min = min_pstate * 100000; + policy->max = max_pstate * 100000; + + /* cpuinfo and default policy values */ + policy->cpuinfo.min_freq = cpu->pstate.min_pstate * 100000; + policy->cpuinfo.max_freq = cpu->pstate.turbo_pstate * 100000; + policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL; + cpumask_set_cpu(policy->cpu, policy->cpus); + + return 0; +} + +static struct cpufreq_driver intel_pstate_driver = { + .flags = CPUFREQ_CONST_LOOPS, + .verify = intel_pstate_verify_policy, + .setpolicy = intel_pstate_set_policy, + .get = intel_pstate_get, + .init = intel_pstate_cpu_init, + .exit = intel_pstate_cpu_exit, + .name = "intel_pstate", + .owner = THIS_MODULE, +}; + +static void intel_pstate_exit(void) +{ + int cpu; + + sysfs_remove_group(intel_pstate_kobject, + &intel_pstate_attr_group); + debugfs_remove_recursive(debugfs_parent); + + cpufreq_unregister_driver(&intel_pstate_driver); + + if (!all_cpu_data) + return; + + get_online_cpus(); + for_each_online_cpu(cpu) { + if (all_cpu_data[cpu]) { + del_timer_sync(&all_cpu_data[cpu]->timer); + kfree(all_cpu_data[cpu]); + } + } + + put_online_cpus(); + vfree(all_cpu_data); +} +module_exit(intel_pstate_exit); + +static int __initdata no_load; + +static int __init intel_pstate_init(void) +{ + int rc = 0; + const struct x86_cpu_id *id; + + if (no_load) + return -ENODEV; + + id = x86_match_cpu(intel_pstate_cpu_ids); + if (!id) + return -ENODEV; + + pr_info("Intel P-state driver initializing.\n"); + + all_cpu_data = vmalloc(sizeof(void *) * num_possible_cpus()); + if (!all_cpu_data) + return -ENOMEM; + memset(all_cpu_data, 0, sizeof(void *) * num_possible_cpus()); + + rc = cpufreq_register_driver(&intel_pstate_driver); + if (rc) + goto out; + + intel_pstate_debug_expose_params(); + intel_pstate_sysfs_expose_params(); + return rc; +out: + intel_pstate_exit(); + return -ENODEV; +} +device_initcall(intel_pstate_init); + +static int __init intel_pstate_setup(char *str) +{ + if (!str) + return -EINVAL; + + if (!strcmp(str, "disable")) + no_load = 1; + return 0; +} +early_param("intel_pstate", intel_pstate_setup); + +MODULE_AUTHOR("Dirk Brandewie <dirk.j.brandewie@intel.com>"); +MODULE_DESCRIPTION("'intel_pstate' - P state driver Intel Core processors"); +MODULE_LICENSE("GPL"); |