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Diffstat (limited to 'drivers/base/power/opp.c')
-rw-r--r--drivers/base/power/opp.c196
1 files changed, 155 insertions, 41 deletions
diff --git a/drivers/base/power/opp.c b/drivers/base/power/opp.c
index 89ced955fafa..2d195f3a1998 100644
--- a/drivers/base/power/opp.c
+++ b/drivers/base/power/opp.c
@@ -49,11 +49,12 @@
* are protected by the dev_opp_list_lock for integrity.
* IMPORTANT: the opp nodes should be maintained in increasing
* order.
+ * @dynamic: not-created from static DT entries.
* @available: true/false - marks if this OPP as available or not
* @rate: Frequency in hertz
* @u_volt: Nominal voltage in microvolts corresponding to this OPP
* @dev_opp: points back to the device_opp struct this opp belongs to
- * @head: RCU callback head used for deferred freeing
+ * @rcu_head: RCU callback head used for deferred freeing
*
* This structure stores the OPP information for a given device.
*/
@@ -61,11 +62,12 @@ struct dev_pm_opp {
struct list_head node;
bool available;
+ bool dynamic;
unsigned long rate;
unsigned long u_volt;
struct device_opp *dev_opp;
- struct rcu_head head;
+ struct rcu_head rcu_head;
};
/**
@@ -76,7 +78,8 @@ struct dev_pm_opp {
* RCU usage: nodes are not modified in the list of device_opp,
* however addition is possible and is secured by dev_opp_list_lock
* @dev: device pointer
- * @head: notifier head to notify the OPP availability changes.
+ * @srcu_head: notifier head to notify the OPP availability changes.
+ * @rcu_head: RCU callback head used for deferred freeing
* @opp_list: list of opps
*
* This is an internal data structure maintaining the link to opps attached to
@@ -87,7 +90,8 @@ struct device_opp {
struct list_head node;
struct device *dev;
- struct srcu_notifier_head head;
+ struct srcu_notifier_head srcu_head;
+ struct rcu_head rcu_head;
struct list_head opp_list;
};
@@ -378,30 +382,8 @@ struct dev_pm_opp *dev_pm_opp_find_freq_floor(struct device *dev,
}
EXPORT_SYMBOL_GPL(dev_pm_opp_find_freq_floor);
-/**
- * dev_pm_opp_add() - Add an OPP table from a table definitions
- * @dev: device for which we do this operation
- * @freq: Frequency in Hz for this OPP
- * @u_volt: Voltage in uVolts for this OPP
- *
- * This function adds an opp definition to the opp list and returns status.
- * The opp is made available by default and it can be controlled using
- * dev_pm_opp_enable/disable functions.
- *
- * Locking: The internal device_opp and opp structures are RCU protected.
- * Hence this function internally uses RCU updater strategy with mutex locks
- * to keep the integrity of the internal data structures. Callers should ensure
- * that this function is *NOT* called under RCU protection or in contexts where
- * mutex cannot be locked.
- *
- * Return:
- * 0: On success OR
- * Duplicate OPPs (both freq and volt are same) and opp->available
- * -EEXIST: Freq are same and volt are different OR
- * Duplicate OPPs (both freq and volt are same) and !opp->available
- * -ENOMEM: Memory allocation failure
- */
-int dev_pm_opp_add(struct device *dev, unsigned long freq, unsigned long u_volt)
+static int dev_pm_opp_add_dynamic(struct device *dev, unsigned long freq,
+ unsigned long u_volt, bool dynamic)
{
struct device_opp *dev_opp = NULL;
struct dev_pm_opp *opp, *new_opp;
@@ -417,6 +399,13 @@ int dev_pm_opp_add(struct device *dev, unsigned long freq, unsigned long u_volt)
/* Hold our list modification lock here */
mutex_lock(&dev_opp_list_lock);
+ /* populate the opp table */
+ new_opp->dev_opp = dev_opp;
+ new_opp->rate = freq;
+ new_opp->u_volt = u_volt;
+ new_opp->available = true;
+ new_opp->dynamic = dynamic;
+
/* Check for existing list for 'dev' */
dev_opp = find_device_opp(dev);
if (IS_ERR(dev_opp)) {
@@ -436,19 +425,15 @@ int dev_pm_opp_add(struct device *dev, unsigned long freq, unsigned long u_volt)
}
dev_opp->dev = dev;
- srcu_init_notifier_head(&dev_opp->head);
+ srcu_init_notifier_head(&dev_opp->srcu_head);
INIT_LIST_HEAD(&dev_opp->opp_list);
/* Secure the device list modification */
list_add_rcu(&dev_opp->node, &dev_opp_list);
+ head = &dev_opp->opp_list;
+ goto list_add;
}
- /* populate the opp table */
- new_opp->dev_opp = dev_opp;
- new_opp->rate = freq;
- new_opp->u_volt = u_volt;
- new_opp->available = true;
-
/*
* Insert new OPP in order of increasing frequency
* and discard if already present
@@ -474,6 +459,7 @@ int dev_pm_opp_add(struct device *dev, unsigned long freq, unsigned long u_volt)
return ret;
}
+list_add:
list_add_rcu(&new_opp->node, head);
mutex_unlock(&dev_opp_list_lock);
@@ -481,11 +467,109 @@ int dev_pm_opp_add(struct device *dev, unsigned long freq, unsigned long u_volt)
* Notify the changes in the availability of the operable
* frequency/voltage list.
*/
- srcu_notifier_call_chain(&dev_opp->head, OPP_EVENT_ADD, new_opp);
+ srcu_notifier_call_chain(&dev_opp->srcu_head, OPP_EVENT_ADD, new_opp);
return 0;
}
+
+/**
+ * dev_pm_opp_add() - Add an OPP table from a table definitions
+ * @dev: device for which we do this operation
+ * @freq: Frequency in Hz for this OPP
+ * @u_volt: Voltage in uVolts for this OPP
+ *
+ * This function adds an opp definition to the opp list and returns status.
+ * The opp is made available by default and it can be controlled using
+ * dev_pm_opp_enable/disable functions.
+ *
+ * Locking: The internal device_opp and opp structures are RCU protected.
+ * Hence this function internally uses RCU updater strategy with mutex locks
+ * to keep the integrity of the internal data structures. Callers should ensure
+ * that this function is *NOT* called under RCU protection or in contexts where
+ * mutex cannot be locked.
+ *
+ * Return:
+ * 0: On success OR
+ * Duplicate OPPs (both freq and volt are same) and opp->available
+ * -EEXIST: Freq are same and volt are different OR
+ * Duplicate OPPs (both freq and volt are same) and !opp->available
+ * -ENOMEM: Memory allocation failure
+ */
+int dev_pm_opp_add(struct device *dev, unsigned long freq, unsigned long u_volt)
+{
+ return dev_pm_opp_add_dynamic(dev, freq, u_volt, true);
+}
EXPORT_SYMBOL_GPL(dev_pm_opp_add);
+static void kfree_opp_rcu(struct rcu_head *head)
+{
+ struct dev_pm_opp *opp = container_of(head, struct dev_pm_opp, rcu_head);
+
+ kfree_rcu(opp, rcu_head);
+}
+
+static void kfree_device_rcu(struct rcu_head *head)
+{
+ struct device_opp *device_opp = container_of(head, struct device_opp, rcu_head);
+
+ kfree(device_opp);
+}
+
+void __dev_pm_opp_remove(struct device_opp *dev_opp, struct dev_pm_opp *opp)
+{
+ /*
+ * Notify the changes in the availability of the operable
+ * frequency/voltage list.
+ */
+ srcu_notifier_call_chain(&dev_opp->srcu_head, OPP_EVENT_REMOVE, opp);
+ list_del_rcu(&opp->node);
+ call_srcu(&dev_opp->srcu_head.srcu, &opp->rcu_head, kfree_opp_rcu);
+
+ if (list_empty(&dev_opp->opp_list)) {
+ list_del_rcu(&dev_opp->node);
+ call_srcu(&dev_opp->srcu_head.srcu, &dev_opp->rcu_head,
+ kfree_device_rcu);
+ }
+}
+
+/**
+ * dev_pm_opp_remove() - Remove an OPP from OPP list
+ * @dev: device for which we do this operation
+ * @freq: OPP to remove with matching 'freq'
+ *
+ * This function removes an opp from the opp list.
+ */
+void dev_pm_opp_remove(struct device *dev, unsigned long freq)
+{
+ struct dev_pm_opp *opp;
+ struct device_opp *dev_opp;
+ bool found = false;
+
+ /* Hold our list modification lock here */
+ mutex_lock(&dev_opp_list_lock);
+
+ dev_opp = find_device_opp(dev);
+ if (IS_ERR(dev_opp))
+ goto unlock;
+
+ list_for_each_entry(opp, &dev_opp->opp_list, node) {
+ if (opp->rate == freq) {
+ found = true;
+ break;
+ }
+ }
+
+ if (!found) {
+ dev_warn(dev, "%s: Couldn't find OPP with freq: %lu\n",
+ __func__, freq);
+ goto unlock;
+ }
+
+ __dev_pm_opp_remove(dev_opp, opp);
+unlock:
+ mutex_unlock(&dev_opp_list_lock);
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_remove);
+
/**
* opp_set_availability() - helper to set the availability of an opp
* @dev: device for which we do this operation
@@ -557,14 +641,14 @@ static int opp_set_availability(struct device *dev, unsigned long freq,
list_replace_rcu(&opp->node, &new_opp->node);
mutex_unlock(&dev_opp_list_lock);
- kfree_rcu(opp, head);
+ call_srcu(&dev_opp->srcu_head.srcu, &opp->rcu_head, kfree_opp_rcu);
/* Notify the change of the OPP availability */
if (availability_req)
- srcu_notifier_call_chain(&dev_opp->head, OPP_EVENT_ENABLE,
+ srcu_notifier_call_chain(&dev_opp->srcu_head, OPP_EVENT_ENABLE,
new_opp);
else
- srcu_notifier_call_chain(&dev_opp->head, OPP_EVENT_DISABLE,
+ srcu_notifier_call_chain(&dev_opp->srcu_head, OPP_EVENT_DISABLE,
new_opp);
return 0;
@@ -629,7 +713,7 @@ struct srcu_notifier_head *dev_pm_opp_get_notifier(struct device *dev)
if (IS_ERR(dev_opp))
return ERR_CAST(dev_opp); /* matching type */
- return &dev_opp->head;
+ return &dev_opp->srcu_head;
}
#ifdef CONFIG_OF
@@ -666,7 +750,7 @@ int of_init_opp_table(struct device *dev)
unsigned long freq = be32_to_cpup(val++) * 1000;
unsigned long volt = be32_to_cpup(val++);
- if (dev_pm_opp_add(dev, freq, volt))
+ if (dev_pm_opp_add_dynamic(dev, freq, volt, false))
dev_warn(dev, "%s: Failed to add OPP %ld\n",
__func__, freq);
nr -= 2;
@@ -675,4 +759,34 @@ int of_init_opp_table(struct device *dev)
return 0;
}
EXPORT_SYMBOL_GPL(of_init_opp_table);
+
+/**
+ * of_free_opp_table() - Free OPP table entries created from static DT entries
+ * @dev: device pointer used to lookup device OPPs.
+ *
+ * Free OPPs created using static entries present in DT.
+ */
+void of_free_opp_table(struct device *dev)
+{
+ struct device_opp *dev_opp = find_device_opp(dev);
+ struct dev_pm_opp *opp, *tmp;
+
+ /* Check for existing list for 'dev' */
+ dev_opp = find_device_opp(dev);
+ if (WARN(IS_ERR(dev_opp), "%s: dev_opp: %ld\n", dev_name(dev),
+ PTR_ERR(dev_opp)))
+ return;
+
+ /* Hold our list modification lock here */
+ mutex_lock(&dev_opp_list_lock);
+
+ /* Free static OPPs */
+ list_for_each_entry_safe(opp, tmp, &dev_opp->opp_list, node) {
+ if (!opp->dynamic)
+ __dev_pm_opp_remove(dev_opp, opp);
+ }
+
+ mutex_unlock(&dev_opp_list_lock);
+}
+EXPORT_SYMBOL_GPL(of_free_opp_table);
#endif