diff options
author | 2015-12-28 01:34:35 +0100 | |
---|---|---|
committer | 2015-12-28 01:34:35 +0100 | |
commit | 9ad55cd9e600de238e3937705e642f0253f3bc42 (patch) | |
tree | 09a32fd285cd16d145ade7ca148def347f4f462d /drivers/cpufreq | |
parent | cpufreq: scpi-cpufreq: signedness bug in scpi_get_dvfs_info() (diff) | |
parent | Merge back earlier cpufreq material for v4.5. (diff) | |
download | linux-9ad55cd9e600de238e3937705e642f0253f3bc42.tar.gz linux-9ad55cd9e600de238e3937705e642f0253f3bc42.tar.bz2 linux-9ad55cd9e600de238e3937705e642f0253f3bc42.zip |
Merge back earlier cpufreq material for v4.5.
Diffstat (limited to 'drivers/cpufreq')
-rw-r--r-- | drivers/cpufreq/Kconfig.arm | 12 | ||||
-rw-r--r-- | drivers/cpufreq/Makefile | 1 | ||||
-rw-r--r-- | drivers/cpufreq/arm_big_little.c | 41 | ||||
-rw-r--r-- | drivers/cpufreq/cpufreq-dt.c | 9 | ||||
-rw-r--r-- | drivers/cpufreq/cpufreq_conservative.c | 6 | ||||
-rw-r--r-- | drivers/cpufreq/cpufreq_governor.c | 143 | ||||
-rw-r--r-- | drivers/cpufreq/cpufreq_governor.h | 18 | ||||
-rw-r--r-- | drivers/cpufreq/cpufreq_ondemand.c | 61 | ||||
-rw-r--r-- | drivers/cpufreq/intel_pstate.c | 73 | ||||
-rw-r--r-- | drivers/cpufreq/mt8173-cpufreq.c | 124 | ||||
-rw-r--r-- | drivers/cpufreq/pcc-cpufreq.c | 2 | ||||
-rw-r--r-- | drivers/cpufreq/qoriq-cpufreq.c | 24 | ||||
-rw-r--r-- | drivers/cpufreq/sti-cpufreq.c | 294 |
13 files changed, 673 insertions, 135 deletions
diff --git a/drivers/cpufreq/Kconfig.arm b/drivers/cpufreq/Kconfig.arm index b1f8a73e5a94..0031069b64c9 100644 --- a/drivers/cpufreq/Kconfig.arm +++ b/drivers/cpufreq/Kconfig.arm @@ -6,6 +6,8 @@ config ARM_BIG_LITTLE_CPUFREQ tristate "Generic ARM big LITTLE CPUfreq driver" depends on (ARM_CPU_TOPOLOGY || ARM64) && HAVE_CLK + # if CPU_THERMAL is on and THERMAL=m, ARM_BIT_LITTLE_CPUFREQ cannot be =y + depends on !CPU_THERMAL || THERMAL select PM_OPP help This enables the Generic CPUfreq driver for ARM big.LITTLE platforms. @@ -217,6 +219,16 @@ config ARM_SPEAR_CPUFREQ help This adds the CPUFreq driver support for SPEAr SOCs. +config ARM_STI_CPUFREQ + tristate "STi CPUFreq support" + depends on SOC_STIH407 + help + This driver uses the generic OPP framework to match the running + platform with a predefined set of suitable values. If not provided + we will fall-back so safe-values contained in Device Tree. Enable + this config option if you wish to add CPUFreq support for STi based + SoCs. + config ARM_TEGRA20_CPUFREQ bool "Tegra20 CPUFreq support" depends on ARCH_TEGRA diff --git a/drivers/cpufreq/Makefile b/drivers/cpufreq/Makefile index c0af1a1281c8..9e63fb1b09f8 100644 --- a/drivers/cpufreq/Makefile +++ b/drivers/cpufreq/Makefile @@ -73,6 +73,7 @@ obj-$(CONFIG_ARM_SA1100_CPUFREQ) += sa1100-cpufreq.o obj-$(CONFIG_ARM_SA1110_CPUFREQ) += sa1110-cpufreq.o obj-$(CONFIG_ARM_SCPI_CPUFREQ) += scpi-cpufreq.o obj-$(CONFIG_ARM_SPEAR_CPUFREQ) += spear-cpufreq.o +obj-$(CONFIG_ARM_STI_CPUFREQ) += sti-cpufreq.o obj-$(CONFIG_ARM_TEGRA20_CPUFREQ) += tegra20-cpufreq.o obj-$(CONFIG_ARM_TEGRA124_CPUFREQ) += tegra124-cpufreq.o obj-$(CONFIG_ARM_VEXPRESS_SPC_CPUFREQ) += vexpress-spc-cpufreq.o diff --git a/drivers/cpufreq/arm_big_little.c b/drivers/cpufreq/arm_big_little.c index c5d256caa664..c251247ae661 100644 --- a/drivers/cpufreq/arm_big_little.c +++ b/drivers/cpufreq/arm_big_little.c @@ -23,6 +23,7 @@ #include <linux/cpu.h> #include <linux/cpufreq.h> #include <linux/cpumask.h> +#include <linux/cpu_cooling.h> #include <linux/export.h> #include <linux/module.h> #include <linux/mutex.h> @@ -55,6 +56,7 @@ static bool bL_switching_enabled; #define ACTUAL_FREQ(cluster, freq) ((cluster == A7_CLUSTER) ? freq << 1 : freq) #define VIRT_FREQ(cluster, freq) ((cluster == A7_CLUSTER) ? freq >> 1 : freq) +static struct thermal_cooling_device *cdev[MAX_CLUSTERS]; static struct cpufreq_arm_bL_ops *arm_bL_ops; static struct clk *clk[MAX_CLUSTERS]; static struct cpufreq_frequency_table *freq_table[MAX_CLUSTERS + 1]; @@ -493,6 +495,12 @@ static int bL_cpufreq_init(struct cpufreq_policy *policy) static int bL_cpufreq_exit(struct cpufreq_policy *policy) { struct device *cpu_dev; + int cur_cluster = cpu_to_cluster(policy->cpu); + + if (cur_cluster < MAX_CLUSTERS) { + cpufreq_cooling_unregister(cdev[cur_cluster]); + cdev[cur_cluster] = NULL; + } cpu_dev = get_cpu_device(policy->cpu); if (!cpu_dev) { @@ -507,6 +515,38 @@ static int bL_cpufreq_exit(struct cpufreq_policy *policy) return 0; } +static void bL_cpufreq_ready(struct cpufreq_policy *policy) +{ + struct device *cpu_dev = get_cpu_device(policy->cpu); + int cur_cluster = cpu_to_cluster(policy->cpu); + struct device_node *np; + + /* Do not register a cpu_cooling device if we are in IKS mode */ + if (cur_cluster >= MAX_CLUSTERS) + return; + + np = of_node_get(cpu_dev->of_node); + if (WARN_ON(!np)) + return; + + if (of_find_property(np, "#cooling-cells", NULL)) { + u32 power_coefficient = 0; + + of_property_read_u32(np, "dynamic-power-coefficient", + &power_coefficient); + + cdev[cur_cluster] = of_cpufreq_power_cooling_register(np, + policy->related_cpus, power_coefficient, NULL); + if (IS_ERR(cdev[cur_cluster])) { + dev_err(cpu_dev, + "running cpufreq without cooling device: %ld\n", + PTR_ERR(cdev[cur_cluster])); + cdev[cur_cluster] = NULL; + } + } + of_node_put(np); +} + static struct cpufreq_driver bL_cpufreq_driver = { .name = "arm-big-little", .flags = CPUFREQ_STICKY | @@ -517,6 +557,7 @@ static struct cpufreq_driver bL_cpufreq_driver = { .get = bL_cpufreq_get_rate, .init = bL_cpufreq_init, .exit = bL_cpufreq_exit, + .ready = bL_cpufreq_ready, .attr = cpufreq_generic_attr, }; diff --git a/drivers/cpufreq/cpufreq-dt.c b/drivers/cpufreq/cpufreq-dt.c index 90d64081ddb3..1ceece9d6711 100644 --- a/drivers/cpufreq/cpufreq-dt.c +++ b/drivers/cpufreq/cpufreq-dt.c @@ -407,8 +407,13 @@ static void cpufreq_ready(struct cpufreq_policy *policy) * thermal DT code takes care of matching them. */ if (of_find_property(np, "#cooling-cells", NULL)) { - priv->cdev = of_cpufreq_cooling_register(np, - policy->related_cpus); + u32 power_coefficient = 0; + + of_property_read_u32(np, "dynamic-power-coefficient", + &power_coefficient); + + priv->cdev = of_cpufreq_power_cooling_register(np, + policy->related_cpus, power_coefficient, NULL); if (IS_ERR(priv->cdev)) { dev_err(priv->cpu_dev, "running cpufreq without cooling device: %ld\n", diff --git a/drivers/cpufreq/cpufreq_conservative.c b/drivers/cpufreq/cpufreq_conservative.c index 1fa1deb6e91f..606ad74abe6e 100644 --- a/drivers/cpufreq/cpufreq_conservative.c +++ b/drivers/cpufreq/cpufreq_conservative.c @@ -115,13 +115,13 @@ static void cs_check_cpu(int cpu, unsigned int load) } } -static unsigned int cs_dbs_timer(struct cpu_dbs_info *cdbs, - struct dbs_data *dbs_data, bool modify_all) +static unsigned int cs_dbs_timer(struct cpufreq_policy *policy, bool modify_all) { + struct dbs_data *dbs_data = policy->governor_data; struct cs_dbs_tuners *cs_tuners = dbs_data->tuners; if (modify_all) - dbs_check_cpu(dbs_data, cdbs->shared->policy->cpu); + dbs_check_cpu(dbs_data, policy->cpu); return delay_for_sampling_rate(cs_tuners->sampling_rate); } diff --git a/drivers/cpufreq/cpufreq_governor.c b/drivers/cpufreq/cpufreq_governor.c index b260576ddb12..4de12fd35b1f 100644 --- a/drivers/cpufreq/cpufreq_governor.c +++ b/drivers/cpufreq/cpufreq_governor.c @@ -158,47 +158,55 @@ void dbs_check_cpu(struct dbs_data *dbs_data, int cpu) } EXPORT_SYMBOL_GPL(dbs_check_cpu); -static inline void __gov_queue_work(int cpu, struct dbs_data *dbs_data, - unsigned int delay) +void gov_add_timers(struct cpufreq_policy *policy, unsigned int delay) { - struct cpu_dbs_info *cdbs = dbs_data->cdata->get_cpu_cdbs(cpu); - - mod_delayed_work_on(cpu, system_wq, &cdbs->dwork, delay); -} - -void gov_queue_work(struct dbs_data *dbs_data, struct cpufreq_policy *policy, - unsigned int delay, bool all_cpus) -{ - int i; + struct dbs_data *dbs_data = policy->governor_data; + struct cpu_dbs_info *cdbs; + int cpu; - if (!all_cpus) { - /* - * Use raw_smp_processor_id() to avoid preemptible warnings. - * We know that this is only called with all_cpus == false from - * works that have been queued with *_work_on() functions and - * those works are canceled during CPU_DOWN_PREPARE so they - * can't possibly run on any other CPU. - */ - __gov_queue_work(raw_smp_processor_id(), dbs_data, delay); - } else { - for_each_cpu(i, policy->cpus) - __gov_queue_work(i, dbs_data, delay); + for_each_cpu(cpu, policy->cpus) { + cdbs = dbs_data->cdata->get_cpu_cdbs(cpu); + cdbs->timer.expires = jiffies + delay; + add_timer_on(&cdbs->timer, cpu); } } -EXPORT_SYMBOL_GPL(gov_queue_work); +EXPORT_SYMBOL_GPL(gov_add_timers); -static inline void gov_cancel_work(struct dbs_data *dbs_data, - struct cpufreq_policy *policy) +static inline void gov_cancel_timers(struct cpufreq_policy *policy) { + struct dbs_data *dbs_data = policy->governor_data; struct cpu_dbs_info *cdbs; int i; for_each_cpu(i, policy->cpus) { cdbs = dbs_data->cdata->get_cpu_cdbs(i); - cancel_delayed_work_sync(&cdbs->dwork); + del_timer_sync(&cdbs->timer); } } +void gov_cancel_work(struct cpu_common_dbs_info *shared) +{ + /* Tell dbs_timer_handler() to skip queuing up work items. */ + atomic_inc(&shared->skip_work); + /* + * If dbs_timer_handler() is already running, it may not notice the + * incremented skip_work, so wait for it to complete to prevent its work + * item from being queued up after the cancel_work_sync() below. + */ + gov_cancel_timers(shared->policy); + /* + * In case dbs_timer_handler() managed to run and spawn a work item + * before the timers have been canceled, wait for that work item to + * complete and then cancel all of the timers set up by it. If + * dbs_timer_handler() runs again at that point, it will see the + * positive value of skip_work and won't spawn any more work items. + */ + cancel_work_sync(&shared->work); + gov_cancel_timers(shared->policy); + atomic_set(&shared->skip_work, 0); +} +EXPORT_SYMBOL_GPL(gov_cancel_work); + /* Will return if we need to evaluate cpu load again or not */ static bool need_load_eval(struct cpu_common_dbs_info *shared, unsigned int sampling_rate) @@ -217,29 +225,21 @@ static bool need_load_eval(struct cpu_common_dbs_info *shared, return true; } -static void dbs_timer(struct work_struct *work) +static void dbs_work_handler(struct work_struct *work) { - struct cpu_dbs_info *cdbs = container_of(work, struct cpu_dbs_info, - dwork.work); - struct cpu_common_dbs_info *shared = cdbs->shared; + struct cpu_common_dbs_info *shared = container_of(work, struct + cpu_common_dbs_info, work); struct cpufreq_policy *policy; struct dbs_data *dbs_data; unsigned int sampling_rate, delay; - bool modify_all = true; - - mutex_lock(&shared->timer_mutex); + bool eval_load; policy = shared->policy; - - /* - * Governor might already be disabled and there is no point continuing - * with the work-handler. - */ - if (!policy) - goto unlock; - dbs_data = policy->governor_data; + /* Kill all timers */ + gov_cancel_timers(policy); + if (dbs_data->cdata->governor == GOV_CONSERVATIVE) { struct cs_dbs_tuners *cs_tuners = dbs_data->tuners; @@ -250,14 +250,37 @@ static void dbs_timer(struct work_struct *work) sampling_rate = od_tuners->sampling_rate; } - if (!need_load_eval(cdbs->shared, sampling_rate)) - modify_all = false; + eval_load = need_load_eval(shared, sampling_rate); - delay = dbs_data->cdata->gov_dbs_timer(cdbs, dbs_data, modify_all); - gov_queue_work(dbs_data, policy, delay, modify_all); - -unlock: + /* + * Make sure cpufreq_governor_limits() isn't evaluating load in + * parallel. + */ + mutex_lock(&shared->timer_mutex); + delay = dbs_data->cdata->gov_dbs_timer(policy, eval_load); mutex_unlock(&shared->timer_mutex); + + atomic_dec(&shared->skip_work); + + gov_add_timers(policy, delay); +} + +static void dbs_timer_handler(unsigned long data) +{ + struct cpu_dbs_info *cdbs = (struct cpu_dbs_info *)data; + struct cpu_common_dbs_info *shared = cdbs->shared; + + /* + * Timer handler may not be allowed to queue the work at the moment, + * because: + * - Another timer handler has done that + * - We are stopping the governor + * - Or we are updating the sampling rate of the ondemand governor + */ + if (atomic_inc_return(&shared->skip_work) > 1) + atomic_dec(&shared->skip_work); + else + queue_work(system_wq, &shared->work); } static void set_sampling_rate(struct dbs_data *dbs_data, @@ -287,6 +310,9 @@ static int alloc_common_dbs_info(struct cpufreq_policy *policy, for_each_cpu(j, policy->related_cpus) cdata->get_cpu_cdbs(j)->shared = shared; + mutex_init(&shared->timer_mutex); + atomic_set(&shared->skip_work, 0); + INIT_WORK(&shared->work, dbs_work_handler); return 0; } @@ -297,6 +323,8 @@ static void free_common_dbs_info(struct cpufreq_policy *policy, struct cpu_common_dbs_info *shared = cdbs->shared; int j; + mutex_destroy(&shared->timer_mutex); + for_each_cpu(j, policy->cpus) cdata->get_cpu_cdbs(j)->shared = NULL; @@ -433,7 +461,6 @@ static int cpufreq_governor_start(struct cpufreq_policy *policy, shared->policy = policy; shared->time_stamp = ktime_get(); - mutex_init(&shared->timer_mutex); for_each_cpu(j, policy->cpus) { struct cpu_dbs_info *j_cdbs = cdata->get_cpu_cdbs(j); @@ -450,7 +477,9 @@ static int cpufreq_governor_start(struct cpufreq_policy *policy, if (ignore_nice) j_cdbs->prev_cpu_nice = kcpustat_cpu(j).cpustat[CPUTIME_NICE]; - INIT_DEFERRABLE_WORK(&j_cdbs->dwork, dbs_timer); + __setup_timer(&j_cdbs->timer, dbs_timer_handler, + (unsigned long)j_cdbs, + TIMER_DEFERRABLE | TIMER_IRQSAFE); } if (cdata->governor == GOV_CONSERVATIVE) { @@ -468,8 +497,7 @@ static int cpufreq_governor_start(struct cpufreq_policy *policy, od_ops->powersave_bias_init_cpu(cpu); } - gov_queue_work(dbs_data, policy, delay_for_sampling_rate(sampling_rate), - true); + gov_add_timers(policy, delay_for_sampling_rate(sampling_rate)); return 0; } @@ -483,18 +511,9 @@ static int cpufreq_governor_stop(struct cpufreq_policy *policy, if (!shared || !shared->policy) return -EBUSY; - /* - * Work-handler must see this updated, as it should not proceed any - * further after governor is disabled. And so timer_mutex is taken while - * updating this value. - */ - mutex_lock(&shared->timer_mutex); + gov_cancel_work(shared); shared->policy = NULL; - mutex_unlock(&shared->timer_mutex); - - gov_cancel_work(dbs_data, policy); - mutex_destroy(&shared->timer_mutex); return 0; } diff --git a/drivers/cpufreq/cpufreq_governor.h b/drivers/cpufreq/cpufreq_governor.h index 5621bb03e874..91e767a058a7 100644 --- a/drivers/cpufreq/cpufreq_governor.h +++ b/drivers/cpufreq/cpufreq_governor.h @@ -17,6 +17,7 @@ #ifndef _CPUFREQ_GOVERNOR_H #define _CPUFREQ_GOVERNOR_H +#include <linux/atomic.h> #include <linux/cpufreq.h> #include <linux/kernel_stat.h> #include <linux/module.h> @@ -132,12 +133,14 @@ static void *get_cpu_dbs_info_s(int cpu) \ struct cpu_common_dbs_info { struct cpufreq_policy *policy; /* - * percpu mutex that serializes governor limit change with dbs_timer - * invocation. We do not want dbs_timer to run when user is changing - * the governor or limits. + * Per policy mutex that serializes load evaluation from limit-change + * and work-handler. */ struct mutex timer_mutex; + ktime_t time_stamp; + atomic_t skip_work; + struct work_struct work; }; /* Per cpu structures */ @@ -152,7 +155,7 @@ struct cpu_dbs_info { * wake-up from idle. */ unsigned int prev_load; - struct delayed_work dwork; + struct timer_list timer; struct cpu_common_dbs_info *shared; }; @@ -209,8 +212,7 @@ struct common_dbs_data { struct cpu_dbs_info *(*get_cpu_cdbs)(int cpu); void *(*get_cpu_dbs_info_s)(int cpu); - unsigned int (*gov_dbs_timer)(struct cpu_dbs_info *cdbs, - struct dbs_data *dbs_data, + unsigned int (*gov_dbs_timer)(struct cpufreq_policy *policy, bool modify_all); void (*gov_check_cpu)(int cpu, unsigned int load); int (*init)(struct dbs_data *dbs_data, bool notify); @@ -269,11 +271,11 @@ static ssize_t show_sampling_rate_min_gov_pol \ extern struct mutex cpufreq_governor_lock; +void gov_add_timers(struct cpufreq_policy *policy, unsigned int delay); +void gov_cancel_work(struct cpu_common_dbs_info *shared); void dbs_check_cpu(struct dbs_data *dbs_data, int cpu); int cpufreq_governor_dbs(struct cpufreq_policy *policy, struct common_dbs_data *cdata, unsigned int event); -void gov_queue_work(struct dbs_data *dbs_data, struct cpufreq_policy *policy, - unsigned int delay, bool all_cpus); void od_register_powersave_bias_handler(unsigned int (*f) (struct cpufreq_policy *, unsigned int, unsigned int), unsigned int powersave_bias); diff --git a/drivers/cpufreq/cpufreq_ondemand.c b/drivers/cpufreq/cpufreq_ondemand.c index 03ac6ce54042..eae51070c034 100644 --- a/drivers/cpufreq/cpufreq_ondemand.c +++ b/drivers/cpufreq/cpufreq_ondemand.c @@ -191,10 +191,9 @@ static void od_check_cpu(int cpu, unsigned int load) } } -static unsigned int od_dbs_timer(struct cpu_dbs_info *cdbs, - struct dbs_data *dbs_data, bool modify_all) +static unsigned int od_dbs_timer(struct cpufreq_policy *policy, bool modify_all) { - struct cpufreq_policy *policy = cdbs->shared->policy; + struct dbs_data *dbs_data = policy->governor_data; unsigned int cpu = policy->cpu; struct od_cpu_dbs_info_s *dbs_info = &per_cpu(od_cpu_dbs_info, cpu); @@ -247,40 +246,66 @@ static void update_sampling_rate(struct dbs_data *dbs_data, unsigned int new_rate) { struct od_dbs_tuners *od_tuners = dbs_data->tuners; + struct cpumask cpumask; int cpu; od_tuners->sampling_rate = new_rate = max(new_rate, dbs_data->min_sampling_rate); - for_each_online_cpu(cpu) { + /* + * Lock governor so that governor start/stop can't execute in parallel. + */ + mutex_lock(&od_dbs_cdata.mutex); + + cpumask_copy(&cpumask, cpu_online_mask); + + for_each_cpu(cpu, &cpumask) { struct cpufreq_policy *policy; struct od_cpu_dbs_info_s *dbs_info; + struct cpu_dbs_info *cdbs; + struct cpu_common_dbs_info *shared; unsigned long next_sampling, appointed_at; - policy = cpufreq_cpu_get(cpu); - if (!policy) - continue; - if (policy->governor != &cpufreq_gov_ondemand) { - cpufreq_cpu_put(policy); - continue; - } dbs_info = &per_cpu(od_cpu_dbs_info, cpu); - cpufreq_cpu_put(policy); + cdbs = &dbs_info->cdbs; + shared = cdbs->shared; - if (!delayed_work_pending(&dbs_info->cdbs.dwork)) + /* + * A valid shared and shared->policy means governor hasn't + * stopped or exited yet. + */ + if (!shared || !shared->policy) + continue; + + policy = shared->policy; + + /* clear all CPUs of this policy */ + cpumask_andnot(&cpumask, &cpumask, policy->cpus); + + /* + * Update sampling rate for CPUs whose policy is governed by + * dbs_data. In case of governor_per_policy, only a single + * policy will be governed by dbs_data, otherwise there can be + * multiple policies that are governed by the same dbs_data. + */ + if (dbs_data != policy->governor_data) continue; + /* + * Checking this for any CPU should be fine, timers for all of + * them are scheduled together. + */ next_sampling = jiffies + usecs_to_jiffies(new_rate); - appointed_at = dbs_info->cdbs.dwork.timer.expires; + appointed_at = dbs_info->cdbs.timer.expires; if (time_before(next_sampling, appointed_at)) { - cancel_delayed_work_sync(&dbs_info->cdbs.dwork); - - gov_queue_work(dbs_data, policy, - usecs_to_jiffies(new_rate), true); + gov_cancel_work(shared); + gov_add_timers(policy, usecs_to_jiffies(new_rate)); } } + + mutex_unlock(&od_dbs_cdata.mutex); } static ssize_t store_sampling_rate(struct dbs_data *dbs_data, const char *buf, diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c index 98fb8821382d..cd83d477e32d 100644 --- a/drivers/cpufreq/intel_pstate.c +++ b/drivers/cpufreq/intel_pstate.c @@ -66,6 +66,7 @@ static inline int ceiling_fp(int32_t x) struct sample { int32_t core_pct_busy; + int32_t busy_scaled; u64 aperf; u64 mperf; u64 tsc; @@ -112,6 +113,7 @@ struct cpudata { u64 prev_aperf; u64 prev_mperf; u64 prev_tsc; + u64 prev_cummulative_iowait; struct sample sample; }; @@ -133,6 +135,7 @@ struct pstate_funcs { int (*get_scaling)(void); void (*set)(struct cpudata*, int pstate); void (*get_vid)(struct cpudata *); + int32_t (*get_target_pstate)(struct cpudata *); }; struct cpu_defaults { @@ -140,6 +143,9 @@ struct cpu_defaults { struct pstate_funcs funcs; }; +static inline int32_t get_target_pstate_use_performance(struct cpudata *cpu); +static inline int32_t get_target_pstate_use_cpu_load(struct cpudata *cpu); + static struct pstate_adjust_policy pid_params; static struct pstate_funcs pstate_funcs; static int hwp_active; @@ -738,6 +744,7 @@ static struct cpu_defaults core_params = { .get_turbo = core_get_turbo_pstate, .get_scaling = core_get_scaling, .set = core_set_pstate, + .get_target_pstate = get_target_pstate_use_performance, }, }; @@ -758,6 +765,7 @@ static struct cpu_defaults silvermont_params = { .set = atom_set_pstate, .get_scaling = silvermont_get_scaling, .get_vid = atom_get_vid, + .get_target_pstate = get_target_pstate_use_cpu_load, }, }; @@ -778,6 +786,7 @@ static struct cpu_defaults airmont_params = { .set = atom_set_pstate, .get_scaling = airmont_get_scaling, .get_vid = atom_get_vid, + .get_target_pstate = get_target_pstate_use_cpu_load, }, }; @@ -797,6 +806,7 @@ static struct cpu_defaults knl_params = { .get_turbo = knl_get_turbo_pstate, .get_scaling = core_get_scaling, .set = core_set_pstate, + .get_target_pstate = get_target_pstate_use_performance, }, }; @@ -882,12 +892,11 @@ static inline void intel_pstate_sample(struct cpudata *cpu) local_irq_save(flags); rdmsrl(MSR_IA32_APERF, aperf); rdmsrl(MSR_IA32_MPERF, mperf); - if (cpu->prev_mperf == mperf) { + tsc = rdtsc(); + if ((cpu->prev_mperf == mperf) || (cpu->prev_tsc == tsc)) { local_irq_restore(flags); return; } - - tsc = rdtsc(); local_irq_restore(flags); cpu->last_sample_time = cpu->sample.time; @@ -922,7 +931,43 @@ static inline void intel_pstate_set_sample_time(struct cpudata *cpu) mod_timer_pinned(&cpu->timer, jiffies + delay); } -static inline int32_t intel_pstate_get_scaled_busy(struct cpudata *cpu) +static inline int32_t get_target_pstate_use_cpu_load(struct cpudata *cpu) +{ + struct sample *sample = &cpu->sample; + u64 cummulative_iowait, delta_iowait_us; + u64 delta_iowait_mperf; + u64 mperf, now; + int32_t cpu_load; + + cummulative_iowait = get_cpu_iowait_time_us(cpu->cpu, &now); + + /* + * Convert iowait time into number of IO cycles spent at max_freq. + * IO is considered as busy only for the cpu_load algorithm. For + * performance this is not needed since we always try to reach the + * maximum P-State, so we are already boosting the IOs. + */ + delta_iowait_us = cummulative_iowait - cpu->prev_cummulative_iowait; + delta_iowait_mperf = div64_u64(delta_iowait_us * cpu->pstate.scaling * + cpu->pstate.max_pstate, MSEC_PER_SEC); + + mperf = cpu->sample.mperf + delta_iowait_mperf; + cpu->prev_cummulative_iowait = cummulative_iowait; + + + /* + * The load can be estimated as the ratio of the mperf counter + * running at a constant frequency during active periods + * (C0) and the time stamp counter running at the same frequency + * also during C-states. + */ + cpu_load = div64_u64(int_tofp(100) * mperf, sample->tsc); + cpu->sample.busy_scaled = cpu_load; + + return cpu->pstate.current_pstate - pid_calc(&cpu->pid, cpu_load); +} + +static inline int32_t get_target_pstate_use_performance(struct cpudata *cpu) { int32_t core_busy, max_pstate, current_pstate, sample_ratio; s64 duration_us; @@ -960,30 +1005,24 @@ static inline int32_t intel_pstate_get_scaled_busy(struct cpudata *cpu) core_busy = mul_fp(core_busy, sample_ratio); } - return core_busy; + cpu->sample.busy_scaled = core_busy; + return cpu->pstate.current_pstate - pid_calc(&cpu->pid, core_busy); } static inline void intel_pstate_adjust_busy_pstate(struct cpudata *cpu) { - int32_t busy_scaled; - struct _pid *pid; - signed int ctl; - int from; + int from, target_pstate; struct sample *sample; from = cpu->pstate.current_pstate; - pid = &cpu->pid; - busy_scaled = intel_pstate_get_scaled_busy(cpu); + target_pstate = pstate_funcs.get_target_pstate(cpu); - ctl = pid_calc(pid, busy_scaled); - - /* Negative values of ctl increase the pstate and vice versa */ - intel_pstate_set_pstate(cpu, cpu->pstate.current_pstate - ctl, true); + intel_pstate_set_pstate(cpu, target_pstate, true); sample = &cpu->sample; trace_pstate_sample(fp_toint(sample->core_pct_busy), - fp_toint(busy_scaled), + fp_toint(sample->busy_scaled), from, cpu->pstate.current_pstate, sample->mperf, @@ -1237,6 +1276,8 @@ static void copy_cpu_funcs(struct pstate_funcs *funcs) pstate_funcs.get_scaling = funcs->get_scaling; pstate_funcs.set = funcs->set; pstate_funcs.get_vid = funcs->get_vid; + pstate_funcs.get_target_pstate = funcs->get_target_pstate; + } #if IS_ENABLED(CONFIG_ACPI) diff --git a/drivers/cpufreq/mt8173-cpufreq.c b/drivers/cpufreq/mt8173-cpufreq.c index 83001dc5b646..fd601b92f5ec 100644 --- a/drivers/cpufreq/mt8173-cpufreq.c +++ b/drivers/cpufreq/mt8173-cpufreq.c @@ -41,16 +41,35 @@ * the original PLL becomes stable at target frequency. */ struct mtk_cpu_dvfs_info { + struct cpumask cpus; struct device *cpu_dev; struct regulator *proc_reg; struct regulator *sram_reg; struct clk *cpu_clk; struct clk *inter_clk; struct thermal_cooling_device *cdev; + struct list_head list_head; int intermediate_voltage; bool need_voltage_tracking; }; +static LIST_HEAD(dvfs_info_list); + +static struct mtk_cpu_dvfs_info *mtk_cpu_dvfs_info_lookup(int cpu) +{ + struct mtk_cpu_dvfs_info *info; + struct list_head *list; + + list_for_each(list, &dvfs_info_list) { + info = list_entry(list, struct mtk_cpu_dvfs_info, list_head); + + if (cpumask_test_cpu(cpu, &info->cpus)) + return info; + } + + return NULL; +} + static int mtk_cpufreq_voltage_tracking(struct mtk_cpu_dvfs_info *info, int new_vproc) { @@ -59,7 +78,10 @@ static int mtk_cpufreq_voltage_tracking(struct mtk_cpu_dvfs_info *info, int old_vproc, old_vsram, new_vsram, vsram, vproc, ret; old_vproc = regulator_get_voltage(proc_reg); - old_vsram = regulator_get_voltage(sram_reg); + if (old_vproc < 0) { + pr_err("%s: invalid Vproc value: %d\n", __func__, old_vproc); + return old_vproc; + } /* Vsram should not exceed the maximum allowed voltage of SoC. */ new_vsram = min(new_vproc + MIN_VOLT_SHIFT, MAX_VOLT_LIMIT); @@ -72,7 +94,17 @@ static int mtk_cpufreq_voltage_tracking(struct mtk_cpu_dvfs_info *info, */ do { old_vsram = regulator_get_voltage(sram_reg); + if (old_vsram < 0) { + pr_err("%s: invalid Vsram value: %d\n", + __func__, old_vsram); + return old_vsram; + } old_vproc = regulator_get_voltage(proc_reg); + if (old_vproc < 0) { + pr_err("%s: invalid Vproc value: %d\n", + __func__, old_vproc); + return old_vproc; + } vsram = min(new_vsram, old_vproc + MAX_VOLT_SHIFT); @@ -117,7 +149,17 @@ static int mtk_cpufreq_voltage_tracking(struct mtk_cpu_dvfs_info *info, */ do { old_vproc = regulator_get_voltage(proc_reg); + if (old_vproc < 0) { + pr_err("%s: invalid Vproc value: %d\n", + __func__, old_vproc); + return old_vproc; + } old_vsram = regulator_get_voltage(sram_reg); + if (old_vsram < 0) { + pr_err("%s: invalid Vsram value: %d\n", + __func__, old_vsram); + return old_vsram; + } vproc = max(new_vproc, old_vsram - MAX_VOLT_SHIFT); ret = regulator_set_voltage(proc_reg, vproc, @@ -185,6 +227,10 @@ static int mtk_cpufreq_set_target(struct cpufreq_policy *policy, old_freq_hz = clk_get_rate(cpu_clk); old_vproc = regulator_get_voltage(info->proc_reg); + if (old_vproc < 0) { + pr_err("%s: invalid Vproc value: %d\n", __func__, old_vproc); + return old_vproc; + } freq_hz = freq_table[index].frequency * 1000; @@ -375,6 +421,9 @@ static int mtk_cpu_dvfs_info_init(struct mtk_cpu_dvfs_info *info, int cpu) */ info->need_voltage_tracking = !IS_ERR(sram_reg); + /* CPUs in the same cluster share a clock and power domain. */ + cpumask_copy(&info->cpus, &cpu_topology[cpu].core_sibling); + return 0; out_free_opp_table: @@ -413,22 +462,18 @@ static int mtk_cpufreq_init(struct cpufreq_policy *policy) struct cpufreq_frequency_table *freq_table; int ret; - info = kzalloc(sizeof(*info), GFP_KERNEL); - if (!info) - return -ENOMEM; - - ret = mtk_cpu_dvfs_info_init(info, policy->cpu); - if (ret) { - pr_err("%s failed to initialize dvfs info for cpu%d\n", - __func__, policy->cpu); - goto out_free_dvfs_info; + info = mtk_cpu_dvfs_info_lookup(policy->cpu); + if (!info) { + pr_err("dvfs info for cpu%d is not initialized.\n", + policy->cpu); + return -EINVAL; } ret = dev_pm_opp_init_cpufreq_table(info->cpu_dev, &freq_table); if (ret) { pr_err("failed to init cpufreq table for cpu%d: %d\n", policy->cpu, ret); - goto out_release_dvfs_info; + return ret; } ret = cpufreq_table_validate_and_show(policy, freq_table); @@ -437,8 +482,7 @@ static int mtk_cpufreq_init(struct cpufreq_policy *policy) goto out_free_cpufreq_table; } - /* CPUs in the same cluster share a clock and power domain. */ - cpumask_copy(policy->cpus, &cpu_topology[policy->cpu].core_sibling); + cpumask_copy(policy->cpus, &info->cpus); policy->driver_data = info; policy->clk = info->cpu_clk; @@ -446,13 +490,6 @@ static int mtk_cpufreq_init(struct cpufreq_policy *policy) out_free_cpufreq_table: dev_pm_opp_free_cpufreq_table(info->cpu_dev, &freq_table); - -out_release_dvfs_info: - mtk_cpu_dvfs_info_release(info); - -out_free_dvfs_info: - kfree(info); - return ret; } @@ -462,14 +499,13 @@ static int mtk_cpufreq_exit(struct cpufreq_policy *policy) cpufreq_cooling_unregister(info->cdev); dev_pm_opp_free_cpufreq_table(info->cpu_dev, &policy->freq_table); - mtk_cpu_dvfs_info_release(info); - kfree(info); return 0; } static struct cpufreq_driver mt8173_cpufreq_driver = { - .flags = CPUFREQ_STICKY | CPUFREQ_NEED_INITIAL_FREQ_CHECK, + .flags = CPUFREQ_STICKY | CPUFREQ_NEED_INITIAL_FREQ_CHECK | + CPUFREQ_HAVE_GOVERNOR_PER_POLICY, .verify = cpufreq_generic_frequency_table_verify, .target_index = mtk_cpufreq_set_target, .get = cpufreq_generic_get, @@ -482,11 +518,47 @@ static struct cpufreq_driver mt8173_cpufreq_driver = { static int mt8173_cpufreq_probe(struct platform_device *pdev) { - int ret; + struct mtk_cpu_dvfs_info *info; + struct list_head *list, *tmp; + int cpu, ret; + + for_each_possible_cpu(cpu) { + info = mtk_cpu_dvfs_info_lookup(cpu); + if (info) + continue; + + info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL); + if (!info) { + ret = -ENOMEM; + goto release_dvfs_info_list; + } + + ret = mtk_cpu_dvfs_info_init(info, cpu); + if (ret) { + dev_err(&pdev->dev, + "failed to initialize dvfs info for cpu%d\n", + cpu); + goto release_dvfs_info_list; + } + + list_add(&info->list_head, &dvfs_info_list); + } ret = cpufreq_register_driver(&mt8173_cpufreq_driver); - if (ret) - pr_err("failed to register mtk cpufreq driver\n"); + if (ret) { + dev_err(&pdev->dev, "failed to register mtk cpufreq driver\n"); + goto release_dvfs_info_list; + } + + return 0; + +release_dvfs_info_list: + list_for_each_safe(list, tmp, &dvfs_info_list) { + info = list_entry(list, struct mtk_cpu_dvfs_info, list_head); + + mtk_cpu_dvfs_info_release(info); + list_del(list); + } return ret; } diff --git a/drivers/cpufreq/pcc-cpufreq.c b/drivers/cpufreq/pcc-cpufreq.c index 2a0d58959acf..808a320e9d5d 100644 --- a/drivers/cpufreq/pcc-cpufreq.c +++ b/drivers/cpufreq/pcc-cpufreq.c @@ -555,6 +555,8 @@ static int pcc_cpufreq_cpu_init(struct cpufreq_policy *policy) policy->min = policy->cpuinfo.min_freq = ioread32(&pcch_hdr->minimum_frequency) * 1000; + policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL; + pr_debug("init: policy->max is %d, policy->min is %d\n", policy->max, policy->min); out: diff --git a/drivers/cpufreq/qoriq-cpufreq.c b/drivers/cpufreq/qoriq-cpufreq.c index 358f0752c31e..b23e525a7af3 100644 --- a/drivers/cpufreq/qoriq-cpufreq.c +++ b/drivers/cpufreq/qoriq-cpufreq.c @@ -12,6 +12,7 @@ #include <linux/clk.h> #include <linux/cpufreq.h> +#include <linux/cpu_cooling.h> #include <linux/errno.h> #include <linux/init.h> #include <linux/kernel.h> @@ -33,6 +34,7 @@ struct cpu_data { struct clk **pclk; struct cpufreq_frequency_table *table; + struct thermal_cooling_device *cdev; }; /** @@ -321,6 +323,27 @@ static int qoriq_cpufreq_target(struct cpufreq_policy *policy, return clk_set_parent(policy->clk, parent); } + +static void qoriq_cpufreq_ready(struct cpufreq_policy *policy) +{ + struct cpu_data *cpud = policy->driver_data; + struct device_node *np = of_get_cpu_node(policy->cpu, NULL); + + if (of_find_property(np, "#cooling-cells", NULL)) { + cpud->cdev = of_cpufreq_cooling_register(np, + policy->related_cpus); + + if (IS_ERR(cpud->cdev)) { + pr_err("Failed to register cooling device cpu%d: %ld\n", + policy->cpu, PTR_ERR(cpud->cdev)); + + cpud->cdev = NULL; + } + } + + of_node_put(np); +} + static struct cpufreq_driver qoriq_cpufreq_driver = { .name = "qoriq_cpufreq", .flags = CPUFREQ_CONST_LOOPS, @@ -329,6 +352,7 @@ static struct cpufreq_driver qoriq_cpufreq_driver = { .verify = cpufreq_generic_frequency_table_verify, .target_index = qoriq_cpufreq_target, .get = cpufreq_generic_get, + .ready = qoriq_cpufreq_ready, .attr = cpufreq_generic_attr, }; diff --git a/drivers/cpufreq/sti-cpufreq.c b/drivers/cpufreq/sti-cpufreq.c new file mode 100644 index 000000000000..a9c659f58974 --- /dev/null +++ b/drivers/cpufreq/sti-cpufreq.c @@ -0,0 +1,294 @@ +/* + * Match running platform with pre-defined OPP values for CPUFreq + * + * Author: Ajit Pal Singh <ajitpal.singh@st.com> + * Lee Jones <lee.jones@linaro.org> + * + * Copyright (C) 2015 STMicroelectronics (R&D) Limited + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the version 2 of the GNU General Public License as + * published by the Free Software Foundation + */ + +#include <linux/cpu.h> +#include <linux/io.h> +#include <linux/mfd/syscon.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_platform.h> +#include <linux/pm_opp.h> +#include <linux/regmap.h> + +#define VERSION_ELEMENTS 3 +#define MAX_PCODE_NAME_LEN 7 + +#define VERSION_SHIFT 28 +#define HW_INFO_INDEX 1 +#define MAJOR_ID_INDEX 1 +#define MINOR_ID_INDEX 2 + +/* + * Only match on "suitable for ALL versions" entries + * + * This will be used with the BIT() macro. It sets the + * top bit of a 32bit value and is equal to 0x80000000. + */ +#define DEFAULT_VERSION 31 + +enum { + PCODE = 0, + SUBSTRATE, + DVFS_MAX_REGFIELDS, +}; + +/** + * ST CPUFreq Driver Data + * + * @cpu_node CPU's OF node + * @syscfg_eng Engineering Syscon register map + * @regmap Syscon register map + */ +static struct sti_cpufreq_ddata { + struct device *cpu; + struct regmap *syscfg_eng; + struct regmap *syscfg; +} ddata; + +static int sti_cpufreq_fetch_major(void) { + struct device_node *np = ddata.cpu->of_node; + struct device *dev = ddata.cpu; + unsigned int major_offset; + unsigned int socid; + int ret; + + ret = of_property_read_u32_index(np, "st,syscfg", + MAJOR_ID_INDEX, &major_offset); + if (ret) { + dev_err(dev, "No major number offset provided in %s [%d]\n", + np->full_name, ret); + return ret; + } + + ret = regmap_read(ddata.syscfg, major_offset, &socid); + if (ret) { + dev_err(dev, "Failed to read major number from syscon [%d]\n", + ret); + return ret; + } + + return ((socid >> VERSION_SHIFT) & 0xf) + 1; +} + +static int sti_cpufreq_fetch_minor(void) +{ + struct device *dev = ddata.cpu; + struct device_node *np = dev->of_node; + unsigned int minor_offset; + unsigned int minid; + int ret; + + ret = of_property_read_u32_index(np, "st,syscfg-eng", + MINOR_ID_INDEX, &minor_offset); + if (ret) { + dev_err(dev, + "No minor number offset provided %s [%d]\n", + np->full_name, ret); + return ret; + } + + ret = regmap_read(ddata.syscfg_eng, minor_offset, &minid); + if (ret) { + dev_err(dev, + "Failed to read the minor number from syscon [%d]\n", + ret); + return ret; + } + + return minid & 0xf; +} + +static int sti_cpufreq_fetch_regmap_field(const struct reg_field *reg_fields, + int hw_info_offset, int field) +{ + struct regmap_field *regmap_field; + struct reg_field reg_field = reg_fields[field]; + struct device *dev = ddata.cpu; + unsigned int value; + int ret; + + reg_field.reg = hw_info_offset; + regmap_field = devm_regmap_field_alloc(dev, + ddata.syscfg_eng, + reg_field); + if (IS_ERR(regmap_field)) { + dev_err(dev, "Failed to allocate reg field\n"); + return PTR_ERR(regmap_field); + } + + ret = regmap_field_read(regmap_field, &value); + if (ret) { + dev_err(dev, "Failed to read %s code\n", + field ? "SUBSTRATE" : "PCODE"); + return ret; + } + + return value; +} + +static const struct reg_field sti_stih407_dvfs_regfields[DVFS_MAX_REGFIELDS] = { + [PCODE] = REG_FIELD(0, 16, 19), + [SUBSTRATE] = REG_FIELD(0, 0, 2), +}; + +static const struct reg_field *sti_cpufreq_match(void) +{ + if (of_machine_is_compatible("st,stih407") || + of_machine_is_compatible("st,stih410")) + return sti_stih407_dvfs_regfields; + + return NULL; +} + +static int sti_cpufreq_set_opp_info(void) +{ + struct device *dev = ddata.cpu; + struct device_node *np = dev->of_node; + const struct reg_field *reg_fields; + unsigned int hw_info_offset; + unsigned int version[VERSION_ELEMENTS]; + int pcode, substrate, major, minor; + int ret; + char name[MAX_PCODE_NAME_LEN]; + + reg_fields = sti_cpufreq_match(); + if (!reg_fields) { + dev_err(dev, "This SoC doesn't support voltage scaling"); + return -ENODEV; + } + + ret = of_property_read_u32_index(np, "st,syscfg-eng", + HW_INFO_INDEX, &hw_info_offset); + if (ret) { + dev_warn(dev, "Failed to read HW info offset from DT\n"); + substrate = DEFAULT_VERSION; + pcode = 0; + goto use_defaults; + } + + pcode = sti_cpufreq_fetch_regmap_field(reg_fields, + hw_info_offset, + PCODE); + if (pcode < 0) { + dev_warn(dev, "Failed to obtain process code\n"); + /* Use default pcode */ + pcode = 0; + } + + substrate = sti_cpufreq_fetch_regmap_field(reg_fields, + hw_info_offset, + SUBSTRATE); + if (substrate) { + dev_warn(dev, "Failed to obtain substrate code\n"); + /* Use default substrate */ + substrate = DEFAULT_VERSION; + } + +use_defaults: + major = sti_cpufreq_fetch_major(); + if (major < 0) { + dev_err(dev, "Failed to obtain major version\n"); + /* Use default major number */ + major = DEFAULT_VERSION; + } + + minor = sti_cpufreq_fetch_minor(); + if (minor < 0) { + dev_err(dev, "Failed to obtain minor version\n"); + /* Use default minor number */ + minor = DEFAULT_VERSION; + } + + snprintf(name, MAX_PCODE_NAME_LEN, "pcode%d", pcode); + + ret = dev_pm_opp_set_prop_name(dev, name); + if (ret) { + dev_err(dev, "Failed to set prop name\n"); + return ret; + } + + version[0] = BIT(major); + version[1] = BIT(minor); + version[2] = BIT(substrate); + + ret = dev_pm_opp_set_supported_hw(dev, version, VERSION_ELEMENTS); + if (ret) { + dev_err(dev, "Failed to set supported hardware\n"); + return ret; + } + + dev_dbg(dev, "pcode: %d major: %d minor: %d substrate: %d\n", + pcode, major, minor, substrate); + dev_dbg(dev, "version[0]: %x version[1]: %x version[2]: %x\n", + version[0], version[1], version[2]); + + return 0; +} + +static int sti_cpufreq_fetch_syscon_regsiters(void) +{ + struct device *dev = ddata.cpu; + struct device_node *np = dev->of_node; + + ddata.syscfg = syscon_regmap_lookup_by_phandle(np, "st,syscfg"); + if (IS_ERR(ddata.syscfg)) { + dev_err(dev, "\"st,syscfg\" not supplied\n"); + return PTR_ERR(ddata.syscfg); + } + + ddata.syscfg_eng = syscon_regmap_lookup_by_phandle(np, "st,syscfg-eng"); + if (IS_ERR(ddata.syscfg_eng)) { + dev_err(dev, "\"st,syscfg-eng\" not supplied\n"); + return PTR_ERR(ddata.syscfg_eng); + } + + return 0; +} + +static int sti_cpufreq_init(void) +{ + int ret; + + ddata.cpu = get_cpu_device(0); + if (!ddata.cpu) { + dev_err(ddata.cpu, "Failed to get device for CPU0\n"); + goto skip_voltage_scaling; + } + + if (!of_get_property(ddata.cpu->of_node, "operating-points-v2", NULL)) { + dev_err(ddata.cpu, "OPP-v2 not supported\n"); + goto skip_voltage_scaling; + } + + ret = sti_cpufreq_fetch_syscon_regsiters(); + if (ret) + goto skip_voltage_scaling; + + ret = sti_cpufreq_set_opp_info(); + if (!ret) + goto register_cpufreq_dt; + +skip_voltage_scaling: + dev_err(ddata.cpu, "Not doing voltage scaling\n"); + +register_cpufreq_dt: + platform_device_register_simple("cpufreq-dt", -1, NULL, 0); + + return 0; +} +module_init(sti_cpufreq_init); + +MODULE_DESCRIPTION("STMicroelectronics CPUFreq/OPP driver"); +MODULE_AUTHOR("Ajitpal Singh <ajitpal.singh@st.com>"); +MODULE_AUTHOR("Lee Jones <lee.jones@linaro.org>"); +MODULE_LICENSE("GPL v2"); |