From ace9429bb58fd418f0c81d4c2835699bddf6bde6 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Thu, 11 Apr 2024 10:27:49 +0200 Subject: Adding upstream version 6.6.15. Signed-off-by: Daniel Baumann --- drivers/devfreq/governor_passive.c | 451 +++++++++++++++++++++++++++++++++++++ 1 file changed, 451 insertions(+) create mode 100644 drivers/devfreq/governor_passive.c (limited to 'drivers/devfreq/governor_passive.c') diff --git a/drivers/devfreq/governor_passive.c b/drivers/devfreq/governor_passive.c new file mode 100644 index 0000000000..953cf9a1e9 --- /dev/null +++ b/drivers/devfreq/governor_passive.c @@ -0,0 +1,451 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * linux/drivers/devfreq/governor_passive.c + * + * Copyright (C) 2016 Samsung Electronics + * Author: Chanwoo Choi + * Author: MyungJoo Ham + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include "governor.h" + +static struct devfreq_cpu_data * +get_parent_cpu_data(struct devfreq_passive_data *p_data, + struct cpufreq_policy *policy) +{ + struct devfreq_cpu_data *parent_cpu_data; + + if (!p_data || !policy) + return NULL; + + list_for_each_entry(parent_cpu_data, &p_data->cpu_data_list, node) + if (parent_cpu_data->first_cpu == cpumask_first(policy->related_cpus)) + return parent_cpu_data; + + return NULL; +} + +static void delete_parent_cpu_data(struct devfreq_passive_data *p_data) +{ + struct devfreq_cpu_data *parent_cpu_data, *tmp; + + list_for_each_entry_safe(parent_cpu_data, tmp, &p_data->cpu_data_list, node) { + list_del(&parent_cpu_data->node); + + if (parent_cpu_data->opp_table) + dev_pm_opp_put_opp_table(parent_cpu_data->opp_table); + + kfree(parent_cpu_data); + } +} + +static unsigned long get_target_freq_by_required_opp(struct device *p_dev, + struct opp_table *p_opp_table, + struct opp_table *opp_table, + unsigned long *freq) +{ + struct dev_pm_opp *opp = NULL, *p_opp = NULL; + unsigned long target_freq; + + if (!p_dev || !p_opp_table || !opp_table || !freq) + return 0; + + p_opp = devfreq_recommended_opp(p_dev, freq, 0); + if (IS_ERR(p_opp)) + return 0; + + opp = dev_pm_opp_xlate_required_opp(p_opp_table, opp_table, p_opp); + dev_pm_opp_put(p_opp); + + if (IS_ERR(opp)) + return 0; + + target_freq = dev_pm_opp_get_freq(opp); + dev_pm_opp_put(opp); + + return target_freq; +} + +static int get_target_freq_with_cpufreq(struct devfreq *devfreq, + unsigned long *target_freq) +{ + struct devfreq_passive_data *p_data = + (struct devfreq_passive_data *)devfreq->data; + struct devfreq_cpu_data *parent_cpu_data; + struct cpufreq_policy *policy; + unsigned long cpu, cpu_cur, cpu_min, cpu_max, cpu_percent; + unsigned long dev_min, dev_max; + unsigned long freq = 0; + int ret = 0; + + for_each_online_cpu(cpu) { + policy = cpufreq_cpu_get(cpu); + if (!policy) { + ret = -EINVAL; + continue; + } + + parent_cpu_data = get_parent_cpu_data(p_data, policy); + if (!parent_cpu_data) { + cpufreq_cpu_put(policy); + continue; + } + + /* Get target freq via required opps */ + cpu_cur = parent_cpu_data->cur_freq * HZ_PER_KHZ; + freq = get_target_freq_by_required_opp(parent_cpu_data->dev, + parent_cpu_data->opp_table, + devfreq->opp_table, &cpu_cur); + if (freq) { + *target_freq = max(freq, *target_freq); + cpufreq_cpu_put(policy); + continue; + } + + /* Use interpolation if required opps is not available */ + devfreq_get_freq_range(devfreq, &dev_min, &dev_max); + + cpu_min = parent_cpu_data->min_freq; + cpu_max = parent_cpu_data->max_freq; + cpu_cur = parent_cpu_data->cur_freq; + + cpu_percent = ((cpu_cur - cpu_min) * 100) / (cpu_max - cpu_min); + freq = dev_min + mult_frac(dev_max - dev_min, cpu_percent, 100); + + *target_freq = max(freq, *target_freq); + cpufreq_cpu_put(policy); + } + + return ret; +} + +static int get_target_freq_with_devfreq(struct devfreq *devfreq, + unsigned long *freq) +{ + struct devfreq_passive_data *p_data + = (struct devfreq_passive_data *)devfreq->data; + struct devfreq *parent_devfreq = (struct devfreq *)p_data->parent; + unsigned long child_freq = ULONG_MAX; + int i, count; + + /* Get target freq via required opps */ + child_freq = get_target_freq_by_required_opp(parent_devfreq->dev.parent, + parent_devfreq->opp_table, + devfreq->opp_table, freq); + if (child_freq) + goto out; + + /* Use interpolation if required opps is not available */ + for (i = 0; i < parent_devfreq->max_state; i++) + if (parent_devfreq->freq_table[i] == *freq) + break; + + if (i == parent_devfreq->max_state) + return -EINVAL; + + if (i < devfreq->max_state) { + child_freq = devfreq->freq_table[i]; + } else { + count = devfreq->max_state; + child_freq = devfreq->freq_table[count - 1]; + } + +out: + *freq = child_freq; + + return 0; +} + +static int devfreq_passive_get_target_freq(struct devfreq *devfreq, + unsigned long *freq) +{ + struct devfreq_passive_data *p_data = + (struct devfreq_passive_data *)devfreq->data; + int ret; + + if (!p_data) + return -EINVAL; + + /* + * If the devfreq device with passive governor has the specific method + * to determine the next frequency, should use the get_target_freq() + * of struct devfreq_passive_data. + */ + if (p_data->get_target_freq) + return p_data->get_target_freq(devfreq, freq); + + switch (p_data->parent_type) { + case DEVFREQ_PARENT_DEV: + ret = get_target_freq_with_devfreq(devfreq, freq); + break; + case CPUFREQ_PARENT_DEV: + ret = get_target_freq_with_cpufreq(devfreq, freq); + break; + default: + ret = -EINVAL; + dev_err(&devfreq->dev, "Invalid parent type\n"); + break; + } + + return ret; +} + +static int cpufreq_passive_notifier_call(struct notifier_block *nb, + unsigned long event, void *ptr) +{ + struct devfreq_passive_data *p_data = + container_of(nb, struct devfreq_passive_data, nb); + struct devfreq *devfreq = (struct devfreq *)p_data->this; + struct devfreq_cpu_data *parent_cpu_data; + struct cpufreq_freqs *freqs = ptr; + unsigned int cur_freq; + int ret; + + if (event != CPUFREQ_POSTCHANGE || !freqs) + return 0; + + parent_cpu_data = get_parent_cpu_data(p_data, freqs->policy); + if (!parent_cpu_data || parent_cpu_data->cur_freq == freqs->new) + return 0; + + cur_freq = parent_cpu_data->cur_freq; + parent_cpu_data->cur_freq = freqs->new; + + mutex_lock(&devfreq->lock); + ret = devfreq_update_target(devfreq, freqs->new); + mutex_unlock(&devfreq->lock); + if (ret) { + parent_cpu_data->cur_freq = cur_freq; + dev_err(&devfreq->dev, "failed to update the frequency.\n"); + return ret; + } + + return 0; +} + +static int cpufreq_passive_unregister_notifier(struct devfreq *devfreq) +{ + struct devfreq_passive_data *p_data + = (struct devfreq_passive_data *)devfreq->data; + int ret; + + if (p_data->nb.notifier_call) { + ret = cpufreq_unregister_notifier(&p_data->nb, + CPUFREQ_TRANSITION_NOTIFIER); + if (ret < 0) + return ret; + } + + delete_parent_cpu_data(p_data); + + return 0; +} + +static int cpufreq_passive_register_notifier(struct devfreq *devfreq) +{ + struct devfreq_passive_data *p_data + = (struct devfreq_passive_data *)devfreq->data; + struct device *dev = devfreq->dev.parent; + struct opp_table *opp_table = NULL; + struct devfreq_cpu_data *parent_cpu_data; + struct cpufreq_policy *policy; + struct device *cpu_dev; + unsigned int cpu; + int ret; + + p_data->cpu_data_list + = (struct list_head)LIST_HEAD_INIT(p_data->cpu_data_list); + + p_data->nb.notifier_call = cpufreq_passive_notifier_call; + ret = cpufreq_register_notifier(&p_data->nb, CPUFREQ_TRANSITION_NOTIFIER); + if (ret) { + dev_err(dev, "failed to register cpufreq notifier\n"); + p_data->nb.notifier_call = NULL; + goto err; + } + + for_each_possible_cpu(cpu) { + policy = cpufreq_cpu_get(cpu); + if (!policy) { + ret = -EPROBE_DEFER; + goto err; + } + + parent_cpu_data = get_parent_cpu_data(p_data, policy); + if (parent_cpu_data) { + cpufreq_cpu_put(policy); + continue; + } + + parent_cpu_data = kzalloc(sizeof(*parent_cpu_data), + GFP_KERNEL); + if (!parent_cpu_data) { + ret = -ENOMEM; + goto err_put_policy; + } + + cpu_dev = get_cpu_device(cpu); + if (!cpu_dev) { + dev_err(dev, "failed to get cpu device\n"); + ret = -ENODEV; + goto err_free_cpu_data; + } + + opp_table = dev_pm_opp_get_opp_table(cpu_dev); + if (IS_ERR(opp_table)) { + dev_err(dev, "failed to get opp_table of cpu%d\n", cpu); + ret = PTR_ERR(opp_table); + goto err_free_cpu_data; + } + + parent_cpu_data->dev = cpu_dev; + parent_cpu_data->opp_table = opp_table; + parent_cpu_data->first_cpu = cpumask_first(policy->related_cpus); + parent_cpu_data->cur_freq = policy->cur; + parent_cpu_data->min_freq = policy->cpuinfo.min_freq; + parent_cpu_data->max_freq = policy->cpuinfo.max_freq; + + list_add_tail(&parent_cpu_data->node, &p_data->cpu_data_list); + cpufreq_cpu_put(policy); + } + + mutex_lock(&devfreq->lock); + ret = devfreq_update_target(devfreq, 0L); + mutex_unlock(&devfreq->lock); + if (ret) + dev_err(dev, "failed to update the frequency\n"); + + return ret; + +err_free_cpu_data: + kfree(parent_cpu_data); +err_put_policy: + cpufreq_cpu_put(policy); +err: + + return ret; +} + +static int devfreq_passive_notifier_call(struct notifier_block *nb, + unsigned long event, void *ptr) +{ + struct devfreq_passive_data *data + = container_of(nb, struct devfreq_passive_data, nb); + struct devfreq *devfreq = (struct devfreq *)data->this; + struct devfreq *parent = (struct devfreq *)data->parent; + struct devfreq_freqs *freqs = (struct devfreq_freqs *)ptr; + unsigned long freq = freqs->new; + int ret = 0; + + mutex_lock_nested(&devfreq->lock, SINGLE_DEPTH_NESTING); + switch (event) { + case DEVFREQ_PRECHANGE: + if (parent->previous_freq > freq) + ret = devfreq_update_target(devfreq, freq); + + break; + case DEVFREQ_POSTCHANGE: + if (parent->previous_freq < freq) + ret = devfreq_update_target(devfreq, freq); + break; + } + mutex_unlock(&devfreq->lock); + + if (ret < 0) + dev_warn(&devfreq->dev, + "failed to update devfreq using passive governor\n"); + + return NOTIFY_DONE; +} + +static int devfreq_passive_unregister_notifier(struct devfreq *devfreq) +{ + struct devfreq_passive_data *p_data + = (struct devfreq_passive_data *)devfreq->data; + struct devfreq *parent = (struct devfreq *)p_data->parent; + struct notifier_block *nb = &p_data->nb; + + return devfreq_unregister_notifier(parent, nb, DEVFREQ_TRANSITION_NOTIFIER); +} + +static int devfreq_passive_register_notifier(struct devfreq *devfreq) +{ + struct devfreq_passive_data *p_data + = (struct devfreq_passive_data *)devfreq->data; + struct devfreq *parent = (struct devfreq *)p_data->parent; + struct notifier_block *nb = &p_data->nb; + + if (!parent) + return -EPROBE_DEFER; + + nb->notifier_call = devfreq_passive_notifier_call; + return devfreq_register_notifier(parent, nb, DEVFREQ_TRANSITION_NOTIFIER); +} + +static int devfreq_passive_event_handler(struct devfreq *devfreq, + unsigned int event, void *data) +{ + struct devfreq_passive_data *p_data + = (struct devfreq_passive_data *)devfreq->data; + int ret = 0; + + if (!p_data) + return -EINVAL; + + p_data->this = devfreq; + + switch (event) { + case DEVFREQ_GOV_START: + if (p_data->parent_type == DEVFREQ_PARENT_DEV) + ret = devfreq_passive_register_notifier(devfreq); + else if (p_data->parent_type == CPUFREQ_PARENT_DEV) + ret = cpufreq_passive_register_notifier(devfreq); + break; + case DEVFREQ_GOV_STOP: + if (p_data->parent_type == DEVFREQ_PARENT_DEV) + WARN_ON(devfreq_passive_unregister_notifier(devfreq)); + else if (p_data->parent_type == CPUFREQ_PARENT_DEV) + WARN_ON(cpufreq_passive_unregister_notifier(devfreq)); + break; + default: + break; + } + + return ret; +} + +static struct devfreq_governor devfreq_passive = { + .name = DEVFREQ_GOV_PASSIVE, + .flags = DEVFREQ_GOV_FLAG_IMMUTABLE, + .get_target_freq = devfreq_passive_get_target_freq, + .event_handler = devfreq_passive_event_handler, +}; + +static int __init devfreq_passive_init(void) +{ + return devfreq_add_governor(&devfreq_passive); +} +subsys_initcall(devfreq_passive_init); + +static void __exit devfreq_passive_exit(void) +{ + int ret; + + ret = devfreq_remove_governor(&devfreq_passive); + if (ret) + pr_err("%s: failed remove governor %d\n", __func__, ret); +} +module_exit(devfreq_passive_exit); + +MODULE_AUTHOR("Chanwoo Choi "); +MODULE_AUTHOR("MyungJoo Ham "); +MODULE_DESCRIPTION("DEVFREQ Passive governor"); +MODULE_LICENSE("GPL v2"); -- cgit v1.2.3