diff options
Diffstat (limited to 'drivers/cpufreq/intel_pstate.c')
| -rw-r--r-- | drivers/cpufreq/intel_pstate.c | 1012 |
1 files changed, 1012 insertions, 0 deletions
diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c new file mode 100644 index 00000000000..86631cb6f7d --- /dev/null +++ b/drivers/cpufreq/intel_pstate.c @@ -0,0 +1,1012 @@ +/* + * intel_pstate.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 <linux/acpi.h> +#include <trace/events/power.h> + +#include <asm/div64.h> +#include <asm/msr.h> +#include <asm/cpu_device_id.h> + +#define BYT_RATIOS 0x66a +#define BYT_VIDS 0x66b +#define BYT_TURBO_RATIOS 0x66c +#define BYT_TURBO_VIDS 0x66d + + +#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 { + int32_t core_pct_busy; + u64 aperf; + u64 mperf; + int freq; + ktime_t time; +}; + +struct pstate_data { + int current_pstate; + int min_pstate; + int max_pstate; + int turbo_pstate; +}; + +struct vid_data { + int min; + int max; + int turbo; + int32_t ratio; +}; + +struct _pid { + int setpoint; + int32_t integral; + int32_t p_gain; + int32_t i_gain; + int32_t d_gain; + int deadband; + int32_t last_err; +}; + +struct cpudata { + int cpu; + + struct timer_list timer; + + struct pstate_data pstate; + struct vid_data vid; + struct _pid pid; + + ktime_t last_sample_time; + u64 prev_aperf; + u64 prev_mperf; + struct sample sample; +}; + +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; +}; + +struct pstate_funcs { + int (*get_max)(void); + int (*get_min)(void); + int (*get_turbo)(void); + void (*set)(struct cpudata*, int pstate); + void (*get_vid)(struct cpudata *); +}; + +struct cpu_defaults { + struct pstate_adjust_policy pid_policy; + struct pstate_funcs funcs; +}; + +static struct pstate_adjust_policy pid_params; +static struct pstate_funcs pstate_funcs; + +struct perf_limits { + int no_turbo; + int turbo_disabled; + int max_perf_pct; + int min_perf_pct; + int32_t max_perf; + int32_t min_perf; + int max_policy_pct; + int max_sysfs_pct; +}; + +static struct perf_limits limits = { + .no_turbo = 0, + .max_perf_pct = 100, + .max_perf = int_tofp(1), + .min_perf_pct = 0, + .min_perf = 0, + .max_policy_pct = 100, + .max_sysfs_pct = 100, +}; + +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 = int_tofp(setpoint) - int_tofp(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, int32_t busy) +{ + signed int result; + int32_t pterm, dterm, fp_error; + int32_t integral_limit; + + fp_error = int_tofp(pid->setpoint) - busy; + + if (abs(fp_error) <= int_tofp(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, fp_error - pid->last_err); + pid->last_err = fp_error; + + result = pterm + mul_fp(pid->integral, pid->i_gain) + dterm; + result = result + (1 << (FRAC_BITS-1)); + return (signed int)fp_toint(result); +} + +static inline void intel_pstate_busy_pid_reset(struct cpudata *cpu) +{ + pid_p_gain_set(&cpu->pid, pid_params.p_gain_pct); + pid_d_gain_set(&cpu->pid, pid_params.d_gain_pct); + pid_i_gain_set(&cpu->pid, pid_params.i_gain_pct); + + pid_reset(&cpu->pid, + pid_params.setpoint, + 100, + pid_params.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", &pid_params.sample_rate_ms}, + {"d_gain_pct", &pid_params.d_gain_pct}, + {"i_gain_pct", &pid_params.i_gain_pct}, + {"deadband", &pid_params.deadband}, + {"setpoint", &pid_params.setpoint}, + {"p_gain_pct", &pid_params.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); + if (limits.turbo_disabled) { + pr_warn("Turbo disabled by BIOS or unavailable on processor\n"); + limits.no_turbo = limits.turbo_disabled; + } + 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_sysfs_pct = clamp_t(int, input, 0 , 100); + limits.max_perf_pct = min(limits.max_policy_pct, limits.max_sysfs_pct); + 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 byt_get_min_pstate(void) +{ + u64 value; + rdmsrl(BYT_RATIOS, value); + return (value >> 8) & 0x7F; +} + +static int byt_get_max_pstate(void) +{ + u64 value; + rdmsrl(BYT_RATIOS, value); + return (value >> 16) & 0x7F; +} + +static int byt_get_turbo_pstate(void) +{ + u64 value; + rdmsrl(BYT_TURBO_RATIOS, value); + return value & 0x7F; +} + +static void byt_set_pstate(struct cpudata *cpudata, int pstate) +{ + u64 val; + int32_t vid_fp; + u32 vid; + + val = pstate << 8; + if (limits.no_turbo && !limits.turbo_disabled) + val |= (u64)1 << 32; + + vid_fp = cpudata->vid.min + mul_fp( + int_tofp(pstate - cpudata->pstate.min_pstate), + cpudata->vid.ratio); + + vid_fp = clamp_t(int32_t, vid_fp, cpudata->vid.min, cpudata->vid.max); + vid = fp_toint(vid_fp); + + if (pstate > cpudata->pstate.max_pstate) + vid = cpudata->vid.turbo; + + val |= vid; + + wrmsrl(MSR_IA32_PERF_CTL, val); +} + +static void byt_get_vid(struct cpudata *cpudata) +{ + u64 value; + + + rdmsrl(BYT_VIDS, value); + cpudata->vid.min = int_tofp((value >> 8) & 0x7f); + cpudata->vid.max = int_tofp((value >> 16) & 0x7f); + cpudata->vid.ratio = div_fp( + cpudata->vid.max - cpudata->vid.min, + int_tofp(cpudata->pstate.max_pstate - + cpudata->pstate.min_pstate)); + + rdmsrl(BYT_TURBO_VIDS, value); + cpudata->vid.turbo = value & 0x7f; +} + + +static int core_get_min_pstate(void) +{ + u64 value; + rdmsrl(MSR_PLATFORM_INFO, value); + return (value >> 40) & 0xFF; +} + +static int core_get_max_pstate(void) +{ + u64 value; + rdmsrl(MSR_PLATFORM_INFO, value); + return (value >> 8) & 0xFF; +} + +static int core_get_turbo_pstate(void) +{ + u64 value; + int nont, ret; + rdmsrl(MSR_NHM_TURBO_RATIO_LIMIT, value); + nont = core_get_max_pstate(); + ret = ((value) & 255); + if (ret <= nont) + ret = nont; + return ret; +} + +static void core_set_pstate(struct cpudata *cpudata, int pstate) +{ + u64 val; + + val = pstate << 8; + if (limits.no_turbo && !limits.turbo_disabled) + val |= (u64)1 << 32; + + wrmsrl_on_cpu(cpudata->cpu, MSR_IA32_PERF_CTL, val); +} + +static struct cpu_defaults core_params = { + .pid_policy = { + .sample_rate_ms = 10, + .deadband = 0, + .setpoint = 97, + .p_gain_pct = 20, + .d_gain_pct = 0, + .i_gain_pct = 0, + }, + .funcs = { + .get_max = core_get_max_pstate, + .get_min = core_get_min_pstate, + .get_turbo = core_get_turbo_pstate, + .set = core_set_pstate, + }, +}; + +static struct cpu_defaults byt_params = { + .pid_policy = { + .sample_rate_ms = 10, + .deadband = 0, + .setpoint = 97, + .p_gain_pct = 14, + .d_gain_pct = 0, + .i_gain_pct = 4, + }, + .funcs = { + .get_max = byt_get_max_pstate, + .get_min = byt_get_min_pstate, + .get_turbo = byt_get_turbo_pstate, + .set = byt_set_pstate, + .get_vid = byt_get_vid, + }, +}; + + +static void intel_pstate_get_min_max(struct cpudata *cpu, int *min, int *max) +{ + int max_perf = cpu->pstate.turbo_pstate; + int max_perf_adj; + int min_perf; + if (limits.no_turbo) + max_perf = cpu->pstate.max_pstate; + + max_perf_adj = fp_toint(mul_fp(int_tofp(max_perf), limits.max_perf)); + *max = clamp_t(int, max_perf_adj, + 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; + + trace_cpu_frequency(pstate * 100000, cpu->cpu); + + cpu->pstate.current_pstate = pstate; + + pstate_funcs.set(cpu, pstate); +} + +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) +{ + cpu->pstate.min_pstate = pstate_funcs.get_min(); + cpu->pstate.max_pstate = pstate_funcs.get_max(); + cpu->pstate.turbo_pstate = pstate_funcs.get_turbo(); + + if (pstate_funcs.get_vid) + pstate_funcs.get_vid(cpu); + intel_pstate_set_pstate(cpu, cpu->pstate.min_pstate); +} + +static inline void intel_pstate_calc_busy(struct cpudata *cpu) +{ + struct sample *sample = &cpu->sample; + int64_t core_pct; + int32_t rem; + + core_pct = int_tofp(sample->aperf) * int_tofp(100); + core_pct = div_u64_rem(core_pct, int_tofp(sample->mperf), &rem); + + if ((rem << 1) >= int_tofp(sample->mperf)) + core_pct += 1; + + sample->freq = fp_toint( + mul_fp(int_tofp(cpu->pstate.max_pstate * 1000), core_pct)); + + sample->core_pct_busy = (int32_t)core_pct; +} + +static inline void intel_pstate_sample(struct cpudata *cpu) +{ + u64 aperf, mperf; + + rdmsrl(MSR_IA32_APERF, aperf); + rdmsrl(MSR_IA32_MPERF, mperf); + + aperf = aperf >> FRAC_BITS; + mperf = mperf >> FRAC_BITS; + + cpu->last_sample_time = cpu->sample.time; + cpu->sample.time = ktime_get(); + cpu->sample.aperf = aperf; + cpu->sample.mperf = mperf; + cpu->sample.aperf -= cpu->prev_aperf; + cpu->sample.mperf -= cpu->prev_mperf; + + intel_pstate_calc_busy(cpu); + + 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 = pid_params.sample_rate_ms; + delay = msecs_to_jiffies(sample_time); + mod_timer_pinned(&cpu->timer, jiffies + delay); +} + +static inline int32_t intel_pstate_get_scaled_busy(struct cpudata *cpu) +{ + int32_t core_busy, max_pstate, current_pstate, sample_ratio; + u32 duration_us; + u32 sample_time; + + core_busy = cpu->sample.core_pct_busy; + max_pstate = int_tofp(cpu->pstate.max_pstate); + current_pstate = int_tofp(cpu->pstate.current_pstate); + core_busy = mul_fp(core_busy, div_fp(max_pstate, current_pstate)); + + sample_time = (pid_params.sample_rate_ms * USEC_PER_MSEC); + duration_us = (u32) ktime_us_delta(cpu->sample.time, + cpu->last_sample_time); + if (duration_us > sample_time * 3) { + sample_ratio = div_fp(int_tofp(sample_time), + int_tofp(duration_us)); + core_busy = mul_fp(core_busy, sample_ratio); + } + + return core_busy; +} + +static inline void intel_pstate_adjust_busy_pstate(struct cpudata *cpu) +{ + int32_t 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 void intel_pstate_timer_func(unsigned long __data) +{ + struct cpudata *cpu = (struct cpudata *) __data; + struct sample *sample; + + intel_pstate_sample(cpu); + + sample = &cpu->sample; + + intel_pstate_adjust_busy_pstate(cpu); + + trace_pstate_sample(fp_toint(sample->core_pct_busy), + fp_toint(intel_pstate_get_scaled_busy(cpu)), + cpu->pstate.current_pstate, + sample->mperf, + sample->aperf, + sample->freq); + + intel_pstate_set_sample_time(cpu); +} + +#define ICPU(model, policy) \ + { X86_VENDOR_INTEL, 6, model, X86_FEATURE_APERFMPERF,\ + (unsigned long)&policy } + +static const struct x86_cpu_id intel_pstate_cpu_ids[] = { + ICPU(0x2a, core_params), + ICPU(0x2d, core_params), + ICPU(0x37, byt_params), + ICPU(0x3a, core_params), + ICPU(0x3c, core_params), + ICPU(0x3d, core_params), + ICPU(0x3e, core_params), + ICPU(0x3f, core_params), + ICPU(0x45, core_params), + ICPU(0x46, core_params), + ICPU(0x4f, core_params), + ICPU(0x56, core_params), + {} +}; +MODULE_DEVICE_TABLE(x86cpu, intel_pstate_cpu_ids); + +static int intel_pstate_init_cpu(unsigned int cpunum) +{ + struct cpudata *cpu; + + all_cpu_data[cpunum] = kzalloc(sizeof(struct cpudata), GFP_KERNEL); + if (!all_cpu_data[cpunum]) + return -ENOMEM; + + cpu = all_cpu_data[cpunum]; + + cpu->cpu = cpunum; + intel_pstate_get_cpu_pstates(cpu); + + 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_sample(cpu); + + 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->sample; + return sample->freq; +} + +static int intel_pstate_set_policy(struct cpufreq_policy *policy) +{ + struct cpudata *cpu; + + cpu = all_cpu_data[policy->cpu]; + + if (!policy->cpuinfo.max_freq) + return -ENODEV; + + 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 = limits.turbo_disabled; + return 0; + } + 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_policy_pct = policy->max * 100 / policy->cpuinfo.max_freq; + limits.max_policy_pct = clamp_t(int, limits.max_policy_pct, 0 , 100); + limits.max_perf_pct = min(limits.max_policy_pct, limits.max_sysfs_pct); + limits.max_perf = div_fp(int_tofp(limits.max_perf_pct), int_tofp(100)); + + return 0; +} + +static int intel_pstate_verify_policy(struct cpufreq_policy *policy) +{ + cpufreq_verify_within_cpu_limits(policy); + + if ((policy->policy != CPUFREQ_POLICY_POWERSAVE) && + (policy->policy != CPUFREQ_POLICY_PERFORMANCE)) + return -EINVAL; + + return 0; +} + +static void intel_pstate_stop_cpu(struct cpufreq_policy *policy) +{ + int cpu_num = policy->cpu; + struct cpudata *cpu = all_cpu_data[cpu_num]; + + pr_info("intel_pstate CPU %d exiting\n", cpu_num); + + del_timer_sync(&all_cpu_data[cpu_num]->timer); + intel_pstate_set_pstate(cpu, cpu->pstate.min_pstate); + kfree(all_cpu_data[cpu_num]); + all_cpu_data[cpu_num] = NULL; +} + +static int intel_pstate_cpu_init(struct cpufreq_policy *policy) +{ + struct cpudata *cpu; + int rc; + u64 misc_en; + + rc = intel_pstate_init_cpu(policy->cpu); + if (rc) + return rc; + + cpu = all_cpu_data[policy->cpu]; + + rdmsrl(MSR_IA32_MISC_ENABLE, misc_en); + if (misc_en & MSR_IA32_MISC_ENABLE_TURBO_DISABLE || + cpu->pstate.max_pstate == cpu->pstate.turbo_pstate) { + limits.turbo_disabled = 1; + limits.no_turbo = 1; + } + if (limits.min_perf_pct == 100 && limits.max_perf_pct == 100) + policy->policy = CPUFREQ_POLICY_PERFORMANCE; + else + policy->policy = CPUFREQ_POLICY_POWERSAVE; + + policy->min = cpu->pstate.min_pstate * 100000; + policy->max = cpu->pstate.turbo_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, + .stop_cpu = intel_pstate_stop_cpu, + .name = "intel_pstate", +}; + +static int __initdata no_load; + +static int intel_pstate_msrs_not_valid(void) +{ + /* Check that all the msr's we are using are valid. */ + u64 aperf, mperf, tmp; + + rdmsrl(MSR_IA32_APERF, aperf); + rdmsrl(MSR_IA32_MPERF, mperf); + + if (!pstate_funcs.get_max() || + !pstate_funcs.get_min() || + !pstate_funcs.get_turbo()) + return -ENODEV; + + rdmsrl(MSR_IA32_APERF, tmp); + if (!(tmp - aperf)) + return -ENODEV; + + rdmsrl(MSR_IA32_MPERF, tmp); + if (!(tmp - mperf)) + return -ENODEV; + + return 0; +} + +static void copy_pid_params(struct pstate_adjust_policy *policy) +{ + pid_params.sample_rate_ms = policy->sample_rate_ms; + pid_params.p_gain_pct = policy->p_gain_pct; + pid_params.i_gain_pct = policy->i_gain_pct; + pid_params.d_gain_pct = policy->d_gain_pct; + pid_params.deadband = policy->deadband; + pid_params.setpoint = policy->setpoint; +} + +static void copy_cpu_funcs(struct pstate_funcs *funcs) +{ + pstate_funcs.get_max = funcs->get_max; + pstate_funcs.get_min = funcs->get_min; + pstate_funcs.get_turbo = funcs->get_turbo; + pstate_funcs.set = funcs->set; + pstate_funcs.get_vid = funcs->get_vid; +} + +#if IS_ENABLED(CONFIG_ACPI) +#include <acpi/processor.h> + +static bool intel_pstate_no_acpi_pss(void) +{ + int i; + + for_each_possible_cpu(i) { + acpi_status status; + union acpi_object *pss; + struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; + struct acpi_processor *pr = per_cpu(processors, i); + + if (!pr) + continue; + + status = acpi_evaluate_object(pr->handle, "_PSS", NULL, &buffer); + if (ACPI_FAILURE(status)) + continue; + + pss = buffer.pointer; + if (pss && pss->type == ACPI_TYPE_PACKAGE) { + kfree(pss); + return false; + } + + kfree(pss); + } + + return true; +} + +struct hw_vendor_info { + u16 valid; + char oem_id[ACPI_OEM_ID_SIZE]; + char oem_table_id[ACPI_OEM_TABLE_ID_SIZE]; +}; + +/* Hardware vendor-specific info that has its own power management modes */ +static struct hw_vendor_info vendor_info[] = { + {1, "HP ", "ProLiant"}, + {0, "", ""}, +}; + +static bool intel_pstate_platform_pwr_mgmt_exists(void) +{ + struct acpi_table_header hdr; + struct hw_vendor_info *v_info; + + if (acpi_disabled + || ACPI_FAILURE(acpi_get_table_header(ACPI_SIG_FADT, 0, &hdr))) + return false; + + for (v_info = vendor_info; v_info->valid; v_info++) { + if (!strncmp(hdr.oem_id, v_info->oem_id, ACPI_OEM_ID_SIZE) + && !strncmp(hdr.oem_table_id, v_info->oem_table_id, ACPI_OEM_TABLE_ID_SIZE) + && intel_pstate_no_acpi_pss()) + return true; + } + + return false; +} +#else /* CONFIG_ACPI not enabled */ +static inline bool intel_pstate_platform_pwr_mgmt_exists(void) { return false; } +#endif /* CONFIG_ACPI */ + +static int __init intel_pstate_init(void) +{ + int cpu, rc = 0; + const struct x86_cpu_id *id; + struct cpu_defaults *cpu_info; + + if (no_load) + return -ENODEV; + + id = x86_match_cpu(intel_pstate_cpu_ids); + if (!id) + return -ENODEV; + + /* + * The Intel pstate driver will be ignored if the platform + * firmware has its own power management modes. + */ + if (intel_pstate_platform_pwr_mgmt_exists()) + return -ENODEV; + + cpu_info = (struct cpu_defaults *)id->driver_data; + + copy_pid_params(&cpu_info->pid_policy); + copy_cpu_funcs(&cpu_info->funcs); + + if (intel_pstate_msrs_not_valid()) + return -ENODEV; + + pr_info("Intel P-state driver initializing.\n"); + + all_cpu_data = vzalloc(sizeof(void *) * num_possible_cpus()); + if (!all_cpu_data) + return -ENOMEM; + + rc = cpufreq_register_driver(&intel_pstate_driver); + if (rc) + goto out; + + intel_pstate_debug_expose_params(); + intel_pstate_sysfs_expose_params(); + + return rc; +out: + 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); + 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"); |