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path: root/drivers/devfreq/governor_passive.c
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Diffstat (limited to 'drivers/devfreq/governor_passive.c')
-rw-r--r--drivers/devfreq/governor_passive.c403
1 files changed, 335 insertions, 68 deletions
diff --git a/drivers/devfreq/governor_passive.c b/drivers/devfreq/governor_passive.c
index fc09324a03e0..72c67979ebe1 100644
--- a/drivers/devfreq/governor_passive.c
+++ b/drivers/devfreq/governor_passive.c
@@ -1,4 +1,4 @@
-// SPDX-License-Identifier: GPL-2.0-only
+	// SPDX-License-Identifier: GPL-2.0-only
 /*
  * linux/drivers/devfreq/governor_passive.c
  *
@@ -8,76 +8,129 @@
  */
 
 #include <linux/module.h>
+#include <linux/cpu.h>
+#include <linux/cpufreq.h>
+#include <linux/cpumask.h>
+#include <linux/slab.h>
 #include <linux/device.h>
 #include <linux/devfreq.h>
 #include "governor.h"
 
-static int devfreq_passive_get_target_freq(struct devfreq *devfreq,
-					unsigned long *freq)
+#define HZ_PER_KHZ	1000
+
+static struct devfreq_cpu_data *
+get_parent_cpu_data(struct devfreq_passive_data *p_data,
+		    struct cpufreq_policy *policy)
 {
-	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;
-	struct dev_pm_opp *opp, *p_opp;
-	int i, count;
+	struct devfreq_cpu_data *parent_cpu_data;
 
-	/*
-	 * 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);
+	if (!p_data || !policy)
+		return NULL;
 
-	/*
-	 * If the parent and passive devfreq device uses the OPP table,
-	 * get the next frequency by using the OPP table.
-	 */
+	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;
 
-	/*
-	 * - parent devfreq device uses the governors except for passive.
-	 * - passive devfreq device uses the passive governor.
-	 *
-	 * Each devfreq has the OPP table. After deciding the new frequency
-	 * from the governor of parent devfreq device, the passive governor
-	 * need to get the index of new frequency on OPP table of parent
-	 * device. And then the index is used for getting the suitable
-	 * new frequency for passive devfreq device.
-	 */
-	if (!devfreq->profile || !devfreq->profile->freq_table
-		|| devfreq->profile->max_state <= 0)
-		return -EINVAL;
+	return NULL;
+}
 
-	/*
-	 * The passive governor have to get the correct frequency from OPP
-	 * list of parent device. Because in this case, *freq is temporary
-	 * value which is decided by ondemand governor.
-	 */
-	if (devfreq->opp_table && parent_devfreq->opp_table) {
-		p_opp = devfreq_recommended_opp(parent_devfreq->dev.parent,
-						freq, 0);
-		if (IS_ERR(p_opp))
-			return PTR_ERR(p_opp);
+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;
 
-		opp = dev_pm_opp_xlate_required_opp(parent_devfreq->opp_table,
-						    devfreq->opp_table, p_opp);
-		dev_pm_opp_put(p_opp);
+	if (!p_dev || !p_opp_table || !opp_table || !freq)
+		return 0;
 
-		if (IS_ERR(opp))
-			goto no_required_opp;
+	p_opp = devfreq_recommended_opp(p_dev, freq, 0);
+	if (IS_ERR(p_opp))
+		return 0;
 
-		*freq = dev_pm_opp_get_freq(opp);
-		dev_pm_opp_put(opp);
+	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);
 	}
 
-no_required_opp:
-	/*
-	 * Get the OPP table's index of decided frequency by governor
-	 * of parent device.
-	 */
+	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->profile->max_state; i++)
 		if (parent_devfreq->profile->freq_table[i] == *freq)
 			break;
@@ -85,7 +138,6 @@ no_required_opp:
 	if (i == parent_devfreq->profile->max_state)
 		return -EINVAL;
 
-	/* Get the suitable frequency by using index of parent device. */
 	if (i < devfreq->profile->max_state) {
 		child_freq = devfreq->profile->freq_table[i];
 	} else {
@@ -93,12 +145,202 @@ no_required_opp:
 		child_freq = devfreq->profile->freq_table[count - 1];
 	}
 
-	/* Return the suitable frequency for passive device. */
+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;
+	struct devfreq_cpu_data *parent_cpu_data;
+	int cpu, ret = 0;
+
+	if (p_data->nb.notifier_call) {
+		ret = cpufreq_unregister_notifier(&p_data->nb,
+					CPUFREQ_TRANSITION_NOTIFIER);
+		if (ret < 0)
+			return ret;
+	}
+
+	for_each_possible_cpu(cpu) {
+		struct cpufreq_policy *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;
+		}
+
+		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);
+		cpufreq_cpu_put(policy);
+	}
+
+	return ret;
+}
+
+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:
+	WARN_ON(cpufreq_passive_unregister_notifier(devfreq));
+
+	return ret;
+}
+
 static int devfreq_passive_notifier_call(struct notifier_block *nb,
 				unsigned long event, void *ptr)
 {
@@ -131,30 +373,55 @@ static int devfreq_passive_notifier_call(struct notifier_block *nb,
 	return NOTIFY_DONE;
 }
 
-static int devfreq_passive_event_handler(struct devfreq *devfreq,
-				unsigned int event, void *data)
+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;
-	int ret = 0;
 
 	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;
+
+	if (!p_data->this)
+		p_data->this = devfreq;
+
 	switch (event) {
 	case DEVFREQ_GOV_START:
-		if (!p_data->this)
-			p_data->this = devfreq;
-
-		nb->notifier_call = devfreq_passive_notifier_call;
-		ret = devfreq_register_notifier(parent, nb,
-					DEVFREQ_TRANSITION_NOTIFIER);
+		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:
-		WARN_ON(devfreq_unregister_notifier(parent, nb,
-					DEVFREQ_TRANSITION_NOTIFIER));
+		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;