In order to prepare for the later commits, this relocates few routines towards the top as they will be used earlier in the code.

Signed-off-by: Viresh Kumar viresh.kumar@linaro.org --- drivers/base/power/opp.c | 277 ++++++++++++++++++++++++----------------------- 1 file changed, 139 insertions(+), 138 deletions(-)

diff --git a/drivers/base/power/opp.c b/drivers/base/power/opp.c index 677fb2843553..8c3fd57975fb 100644 --- a/drivers/base/power/opp.c +++ b/drivers/base/power/opp.c @@ -438,6 +438,102 @@ static struct device_opp *_add_device_opp(struct device *dev) }

/** + * _kfree_device_rcu() - Free device_opp RCU handler + * @head: 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_rcu(device_opp, rcu_head); +} + +/** + * _kfree_opp_rcu() - Free OPP RCU handler + * @head: RCU head + */ +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); +} + +/** + * _opp_remove() - Remove an OPP from a table definition + * @dev_opp: points back to the device_opp struct this opp belongs to + * @opp: pointer to the OPP to remove + * + * This function removes an opp definition from the opp list. + * + * Locking: The internal device_opp and opp structures are RCU protected. + * It is assumed that the caller holds required mutex for an RCU updater + * strategy. + */ +static void _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. + * + * 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. + */ +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; + } + + _opp_remove(dev_opp, opp); +unlock: + mutex_unlock(&dev_opp_list_lock); +} +EXPORT_SYMBOL_GPL(dev_pm_opp_remove); + +/** * _opp_add_dynamic() - Allocate a dynamic OPP. * @dev: device for which we do this operation * @freq: Frequency in Hz for this OPP @@ -570,102 +666,6 @@ int dev_pm_opp_add(struct device *dev, unsigned long freq, unsigned long u_volt) EXPORT_SYMBOL_GPL(dev_pm_opp_add);

/** - * _kfree_opp_rcu() - Free OPP RCU handler - * @head: RCU head - */ -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); -} - -/** - * _kfree_device_rcu() - Free device_opp RCU handler - * @head: 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_rcu(device_opp, rcu_head); -} - -/** - * _opp_remove() - Remove an OPP from a table definition - * @dev_opp: points back to the device_opp struct this opp belongs to - * @opp: pointer to the OPP to remove - * - * This function removes an opp definition from the opp list. - * - * Locking: The internal device_opp and opp structures are RCU protected. - * It is assumed that the caller holds required mutex for an RCU updater - * strategy. - */ -static void _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. - * - * 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. - */ -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; - } - - _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 * @freq: OPP frequency to modify availability @@ -825,6 +825,49 @@ EXPORT_SYMBOL_GPL(dev_pm_opp_get_notifier);

#ifdef CONFIG_OF /** + * 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. + * + * Locking: The internal device_opp and opp structures are RCU protected. + * Hence this function indirectly 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. + */ +void of_free_opp_table(struct device *dev) +{ + struct device_opp *dev_opp; + struct dev_pm_opp *opp, *tmp; + + /* Check for existing list for 'dev' */ + dev_opp = _find_device_opp(dev); + if (IS_ERR(dev_opp)) { + int error = PTR_ERR(dev_opp); + + if (error != -ENODEV) + WARN(1, "%s: dev_opp: %d\n", + IS_ERR_OR_NULL(dev) ? + "Invalid device" : dev_name(dev), + error); + 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) + _opp_remove(dev_opp, opp); + } + + mutex_unlock(&dev_opp_list_lock); +} +EXPORT_SYMBOL_GPL(of_free_opp_table); + +/** * of_init_opp_table() - Initialize opp table from device tree * @dev: device pointer used to lookup device OPPs. * @@ -882,46 +925,4 @@ 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. - * - * Locking: The internal device_opp and opp structures are RCU protected. - * Hence this function indirectly 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. - */ -void of_free_opp_table(struct device *dev) -{ - struct device_opp *dev_opp; - struct dev_pm_opp *opp, *tmp; - - /* Check for existing list for 'dev' */ - dev_opp = _find_device_opp(dev); - if (IS_ERR(dev_opp)) { - int error = PTR_ERR(dev_opp); - if (error != -ENODEV) - WARN(1, "%s: dev_opp: %d\n", - IS_ERR_OR_NULL(dev) ? - "Invalid device" : dev_name(dev), - error); - 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) - _opp_remove(dev_opp, opp); - } - - mutex_unlock(&dev_opp_list_lock); -} -EXPORT_SYMBOL_GPL(of_free_opp_table); #endif

There is no need to complicate _opp_add_dynamic() with allocation of dev_opp as well. Allocate it from _add_device_opp() instead.

Signed-off-by: Viresh Kumar viresh.kumar@linaro.org --- drivers/base/power/opp.c | 39 +++++++++++++++++++-------------------- 1 file changed, 19 insertions(+), 20 deletions(-)

diff --git a/drivers/base/power/opp.c b/drivers/base/power/opp.c index 7895fdd64192..4b646f36f252 100644 --- a/drivers/base/power/opp.c +++ b/drivers/base/power/opp.c @@ -408,11 +408,11 @@ struct dev_pm_opp *dev_pm_opp_find_freq_floor(struct device *dev, EXPORT_SYMBOL_GPL(dev_pm_opp_find_freq_floor);

/** - * _add_device_opp() - Allocate a new device OPP table + * _add_device_opp() - Returns device OPP table * @dev: device for which we do this operation * - * New device node which uses OPPs - used when multiple devices with OPP tables - * are maintained. + * It tries to find an existing table first, if it couldn't find one, it + * allocates a new OPP table and returns that. * * Return: valid device_opp pointer if success, else NULL. */ @@ -420,6 +420,11 @@ static struct device_opp *_add_device_opp(struct device *dev) { struct device_opp *dev_opp;

+ /* Check for existing list for 'dev' first */ + dev_opp = _find_device_opp(dev); + if (!IS_ERR(dev_opp)) + return dev_opp; + /* * Allocate a new device OPP table. In the infrequent case where a new * device is needed to be added, we pay this penalty. @@ -575,8 +580,8 @@ EXPORT_SYMBOL_GPL(dev_pm_opp_remove); static int _opp_add_dynamic(struct device *dev, unsigned long freq, long u_volt, bool dynamic) { - struct device_opp *dev_opp = NULL; - struct dev_pm_opp *opp, *new_opp; + struct device_opp *dev_opp; + struct dev_pm_opp *opp = NULL, *new_opp; struct list_head *head; int ret;

@@ -592,19 +597,11 @@ static int _opp_add_dynamic(struct device *dev, unsigned long freq, 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)) { - dev_opp = _add_device_opp(dev); - if (!dev_opp) { - ret = -ENOMEM; - goto free_opp; - } - - head = &dev_opp->opp_list; - goto list_add; + dev_opp = _add_device_opp(dev); + if (!dev_opp) { + ret = -ENOMEM; + goto free_opp; }

/* @@ -620,17 +617,17 @@ static int _opp_add_dynamic(struct device *dev, unsigned long freq, }

/* Duplicate OPPs ? */ - if (new_opp->rate == opp->rate) { + if (opp && new_opp->rate == opp->rate) { ret = opp->available && new_opp->u_volt == opp->u_volt ? 0 : -EEXIST;

dev_warn(dev, "%s: duplicate OPPs detected. Existing: freq: %lu, volt: %lu, enabled: %d. New: freq: %lu, volt: %lu, enabled: %d\n", __func__, opp->rate, opp->u_volt, opp->available, new_opp->rate, new_opp->u_volt, new_opp->available); - goto free_opp; + goto remove_dev_opp; }

-list_add: + new_opp->dynamic = dynamic; new_opp->dev_opp = dev_opp; list_add_rcu(&new_opp->node, head); mutex_unlock(&dev_opp_list_lock); @@ -642,6 +639,8 @@ static int _opp_add_dynamic(struct device *dev, unsigned long freq, srcu_notifier_call_chain(&dev_opp->srcu_head, OPP_EVENT_ADD, new_opp); return 0;

+remove_dev_opp: + _remove_device_opp(dev_opp); free_opp: mutex_unlock(&dev_opp_list_lock); kfree(new_opp);

With "operating-points-v2" bindings, clock-latency is defined per OPP. Users of this value expect a single value which defines the latency to switch to any clock rate. Find maximum clock-latency-ns from the OPP table to service requests from such users.

Signed-off-by: Viresh Kumar viresh.kumar@linaro.org --- drivers/base/power/opp.c | 41 +++++++++++++++++++++++++++++++++++++++-- include/linux/pm_opp.h | 6 ++++++ 2 files changed, 45 insertions(+), 2 deletions(-)

diff --git a/drivers/base/power/opp.c b/drivers/base/power/opp.c index 3198c3e77224..fe79e5146a29 100644 --- a/drivers/base/power/opp.c +++ b/drivers/base/power/opp.c @@ -57,6 +57,8 @@ * @u_volt_min: Minimum voltage in microvolts corresponding to this OPP * @u_volt_max: Maximum voltage in microvolts corresponding to this OPP * @u_amp: Maximum current drawn by the device in microamperes + * @clock_latency_ns: Latency (in nanoseconds) of switching to this OPP's + * frequency from any other OPP's frequency. * @dev_opp: points back to the device_opp struct this opp belongs to * @rcu_head: RCU callback head used for deferred freeing * @np: OPP's device node. @@ -79,6 +81,7 @@ struct dev_pm_opp { unsigned long u_volt_min; unsigned long u_volt_max; unsigned long u_amp; + unsigned long clock_latency_ns;

struct device_opp *dev_opp; struct rcu_head rcu_head; @@ -113,6 +116,8 @@ struct device_opp { struct srcu_notifier_head srcu_head; struct rcu_head rcu_head; struct list_head opp_list; + + unsigned long clock_latency_ns_max; };

/* @@ -230,6 +235,32 @@ unsigned long dev_pm_opp_get_freq(struct dev_pm_opp *opp) EXPORT_SYMBOL_GPL(dev_pm_opp_get_freq);

/** + * dev_pm_opp_get_max_clock_latency() - Get max clock latency in nanoseconds + * @dev: device for which we do this operation + * + * Return: This function returns the max clock latency in nanoseconds. + * + * Locking: This function takes rcu_read_lock(). + */ +unsigned long dev_pm_opp_get_max_clock_latency(struct device *dev) +{ + struct device_opp *dev_opp; + unsigned long clock_latency_ns; + + rcu_read_lock(); + + dev_opp = _find_device_opp(dev); + if (IS_ERR(dev_opp)) + clock_latency_ns = 0; + else + clock_latency_ns = dev_opp->clock_latency_ns_max; + + rcu_read_unlock(); + return clock_latency_ns; +} +EXPORT_SYMBOL_GPL(dev_pm_opp_get_max_clock_latency); + +/** * dev_pm_opp_get_opp_count() - Get number of opps available in the opp list * @dev: device for which we do this operation * @@ -741,6 +772,8 @@ static int _opp_add_static_v2(struct device *dev, struct device_node *np) new_opp->np = np; new_opp->dynamic = false; new_opp->available = true; + of_property_read_u32(np, "clock-latency-ns", + (u32 *)&new_opp->clock_latency_ns);

/* * TODO: Support multiple regulators @@ -765,9 +798,13 @@ static int _opp_add_static_v2(struct device *dev, struct device_node *np) if (ret) goto free_opp;

- pr_debug("%s: turbo:%d rate:%lu uv:%lu uvmin:%lu uvmax:%lu\n", + if (new_opp->clock_latency_ns > dev_opp->clock_latency_ns_max) + dev_opp->clock_latency_ns_max = new_opp->clock_latency_ns; + + pr_debug("%s: turbo:%d rate:%lu uv:%lu uvmin:%lu uvmax:%lu latency:%lu\n", __func__, new_opp->turbo, new_opp->rate, new_opp->u_volt, - new_opp->u_volt_min, new_opp->u_volt_max); + new_opp->u_volt_min, new_opp->u_volt_max, + new_opp->clock_latency_ns);

mutex_unlock(&dev_opp_list_lock);

diff --git a/include/linux/pm_opp.h b/include/linux/pm_opp.h index cec2d4540914..20324b579adc 100644 --- a/include/linux/pm_opp.h +++ b/include/linux/pm_opp.h @@ -31,6 +31,7 @@ unsigned long dev_pm_opp_get_voltage(struct dev_pm_opp *opp); unsigned long dev_pm_opp_get_freq(struct dev_pm_opp *opp);

int dev_pm_opp_get_opp_count(struct device *dev); +unsigned long dev_pm_opp_get_max_clock_latency(struct device *dev);

struct dev_pm_opp *dev_pm_opp_find_freq_exact(struct device *dev, unsigned long freq, @@ -67,6 +68,11 @@ static inline int dev_pm_opp_get_opp_count(struct device *dev) return 0; }

+static inline unsigned long dev_pm_opp_get_max_clock_latency(struct device *dev) +{ + return 0; +} + static inline struct dev_pm_opp *dev_pm_opp_find_freq_exact(struct device *dev, unsigned long freq, bool available) {

An opp can be shared by multiple devices, for example its very common for CPUs to share the OPPs, i.e. when they share clock/voltage rails.

This patch adds support of shared OPPs to the OPP library.

Instead of a single device, dev_opp will not contain a list of devices that use it. It also senses if the device (we are trying to initialize OPPs for) shares OPPs with a device added earlier and in that case we update the list of devices managed by OPPs instead of duplicating OPPs again.

The same infrastructure will be used for the old OPP bindings, with later patches.

Signed-off-by: Viresh Kumar viresh.kumar@linaro.org --- drivers/base/power/opp.c | 176 ++++++++++++++++++++++++++++++++++++++++------- 1 file changed, 152 insertions(+), 24 deletions(-)

diff --git a/drivers/base/power/opp.c b/drivers/base/power/opp.c index fe79e5146a29..6b554e417b1f 100644 --- a/drivers/base/power/opp.c +++ b/drivers/base/power/opp.c @@ -90,16 +90,33 @@ struct dev_pm_opp { };

/** + * struct device_list_opp - devices managed by 'struct device_opp' + * @node: list node + * @dev: device to which the struct object belongs + * @rcu_head: RCU callback head used for deferred freeing + * + * This is an internal data structure maintaining the list of devices that are + * managed by 'struct device_opp'. + */ +struct device_list_opp { + struct list_head node; + struct device *dev; + struct rcu_head rcu_head; +}; + +/** * struct device_opp - Device opp structure * @node: list node - contains the devices with OPPs that * have been registered. Nodes once added are not modified in this * list. * 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 * @srcu_head: notifier head to notify the OPP availability changes. * @rcu_head: RCU callback head used for deferred freeing + * @dev_list: list of devices that share these OPPs * @opp_list: list of opps + * @np: struct device_node pointer for opp's DT node. + * @shared_opp: OPP is shared between multiple devices. * * This is an internal data structure maintaining the link to opps attached to * a device. This structure is not meant to be shared to users as it is @@ -112,12 +129,14 @@ struct dev_pm_opp { struct device_opp { struct list_head node;

- struct device *dev; struct srcu_notifier_head srcu_head; struct rcu_head rcu_head; + struct list_head dev_list; struct list_head opp_list;

+ struct device_node *np; unsigned long clock_latency_ns_max; + bool shared_opp; };

/* @@ -137,6 +156,40 @@ do { \ "dev_opp_list_lock protection"); \ } while (0)

+static struct device_list_opp *_find_list_dev(struct device *dev, + struct device_opp *dev_opp) +{ + struct device_list_opp *list_dev; + + list_for_each_entry(list_dev, &dev_opp->dev_list, node) + if (list_dev->dev == dev) + return list_dev; + + return NULL; +} + +static struct device_opp *_managed_opp(struct device_node *np) +{ + struct device_opp *dev_opp; + + list_for_each_entry_rcu(dev_opp, &dev_opp_list, node) + if (dev_opp->np == np) { + /* + * Multiple devices can point to the same OPP table and + * so will have same node-pointer, np. + * + * But the OPPs will be considered as shared only if the + * OPP table contains a "opp-shared" property. + */ + if (dev_opp->shared_opp) + return dev_opp; + else + return NULL; + } + + return NULL; +} + /** * _find_device_opp() - find device_opp struct using device pointer * @dev: device pointer used to lookup device OPPs @@ -153,21 +206,18 @@ do { \ */ static struct device_opp *_find_device_opp(struct device *dev) { - struct device_opp *tmp_dev_opp, *dev_opp = ERR_PTR(-ENODEV); + struct device_opp *dev_opp;

if (unlikely(IS_ERR_OR_NULL(dev))) { pr_err("%s: Invalid parameters\n", __func__); return ERR_PTR(-EINVAL); }

- list_for_each_entry_rcu(tmp_dev_opp, &dev_opp_list, node) { - if (tmp_dev_opp->dev == dev) { - dev_opp = tmp_dev_opp; - break; - } - } + list_for_each_entry_rcu(dev_opp, &dev_opp_list, node) + if (_find_list_dev(dev, dev_opp)) + return dev_opp;

- return dev_opp; + return ERR_PTR(-ENODEV); }

/** @@ -454,6 +504,39 @@ struct dev_pm_opp *dev_pm_opp_find_freq_floor(struct device *dev, } EXPORT_SYMBOL_GPL(dev_pm_opp_find_freq_floor);

+/* List-dev Helpers */ +static void _kfree_list_dev_rcu(struct rcu_head *head) +{ + struct device_list_opp *list_dev; + + list_dev = container_of(head, struct device_list_opp, rcu_head); + kfree_rcu(list_dev, rcu_head); +} + +static void _remove_list_dev(struct device_list_opp *list_dev, + struct device_opp *dev_opp) +{ + list_del(&list_dev->node); + call_srcu(&dev_opp->srcu_head.srcu, &list_dev->rcu_head, + _kfree_list_dev_rcu); +} + +static struct device_list_opp *_add_list_dev(struct device *dev, + struct device_opp *dev_opp) +{ + struct device_list_opp *list_dev; + + list_dev = kzalloc(sizeof(*list_dev), GFP_KERNEL); + if (!list_dev) + return NULL; + + /* Initialize list-dev */ + list_add_rcu(&list_dev->node, &dev_opp->dev_list); + list_dev->dev = dev; + + return list_dev; +} + /** * _add_device_opp() - Returns device OPP table * @dev: device for which we do this operation @@ -466,6 +549,7 @@ EXPORT_SYMBOL_GPL(dev_pm_opp_find_freq_floor); static struct device_opp *_add_device_opp(struct device *dev) { struct device_opp *dev_opp; + struct device_list_opp *list_dev;

/* Check for existing list for 'dev' first */ dev_opp = _find_device_opp(dev); @@ -480,7 +564,14 @@ static struct device_opp *_add_device_opp(struct device *dev) if (!dev_opp) return NULL;

- dev_opp->dev = dev; + INIT_LIST_HEAD(&dev_opp->dev_list); + + list_dev = _add_list_dev(dev, dev_opp); + if (!list_dev) { + kfree(dev_opp); + return NULL; + } + srcu_init_notifier_head(&dev_opp->srcu_head); INIT_LIST_HEAD(&dev_opp->opp_list);

@@ -508,9 +599,19 @@ static void _kfree_device_rcu(struct rcu_head *head) */ static void _remove_device_opp(struct device_opp *dev_opp) { + struct device_list_opp *list_dev; + if (!list_empty(&dev_opp->opp_list)) return;

+ list_dev = list_first_entry(&dev_opp->dev_list, struct device_list_opp, + node); + + _remove_list_dev(list_dev, dev_opp); + + /* dev_list must be empty now */ + WARN_ON(!list_empty(&dev_opp->dev_list)); + list_del_rcu(&dev_opp->node); call_srcu(&dev_opp->srcu_head.srcu, &dev_opp->rcu_head, _kfree_device_rcu); @@ -621,7 +722,8 @@ static struct dev_pm_opp *_allocate_opp(struct device *dev, return opp; }

-static int _opp_add(struct dev_pm_opp *new_opp, struct device_opp *dev_opp) +static int _opp_add(struct device *dev, struct dev_pm_opp *new_opp, + struct device_opp *dev_opp) { struct dev_pm_opp *opp = NULL; struct list_head *head = &dev_opp->opp_list; @@ -639,7 +741,7 @@ static int _opp_add(struct dev_pm_opp *new_opp, struct device_opp *dev_opp)

/* Duplicate OPPs ? */ if (opp && new_opp->rate == opp->rate) { - dev_warn(dev_opp->dev, + dev_warn(dev, "%s: duplicate OPPs detected. Existing: freq: %lu, volt: %lu, enabled: %d. New: freq: %lu, volt: %lu, enabled: %d\n", __func__, opp->rate, opp->u_volt, opp->available, new_opp->rate, new_opp->u_volt, new_opp->available); @@ -702,7 +804,7 @@ static int _opp_add_dynamic(struct device *dev, unsigned long freq, new_opp->available = true; new_opp->dynamic = dynamic;

- ret = _opp_add(new_opp, dev_opp); + ret = _opp_add(dev, new_opp, dev_opp); if (ret) goto free_opp;

@@ -794,7 +896,7 @@ static int _opp_add_static_v2(struct device *dev, struct device_node *np)

of_property_read_u32(np, "opp-microamp", (u32 *)&new_opp->u_amp);

- ret = _opp_add(new_opp, dev_opp); + ret = _opp_add(dev, new_opp, dev_opp); if (ret) goto free_opp;

@@ -1027,6 +1129,9 @@ void of_free_opp_table(struct device *dev) struct device_opp *dev_opp; struct dev_pm_opp *opp, *tmp;

+ /* Hold our list modification lock here */ + mutex_lock(&dev_opp_list_lock); + /* Check for existing list for 'dev' */ dev_opp = _find_device_opp(dev); if (IS_ERR(dev_opp)) { @@ -1037,18 +1142,21 @@ void of_free_opp_table(struct device *dev) IS_ERR_OR_NULL(dev) ? "Invalid device" : dev_name(dev), error); - return; + goto unlock; }

- /* 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) - _opp_remove(dev_opp, opp, true); + /* Find if dev_opp manages a single device */ + if (list_is_singular(&dev_opp->dev_list)) { + /* Free static OPPs */ + list_for_each_entry_safe(opp, tmp, &dev_opp->opp_list, node) { + if (!opp->dynamic) + _opp_remove(dev_opp, opp, true); + } + } else { + _remove_list_dev(_find_list_dev(dev, dev_opp), dev_opp); }

+unlock: mutex_unlock(&dev_opp_list_lock); } EXPORT_SYMBOL_GPL(of_free_opp_table); @@ -1074,6 +1182,7 @@ static int _of_init_opp_table_v2(struct device *dev, const struct property *prop) { struct device_node *opp_np, *np; + struct device_opp *dev_opp; int ret = 0, count = 0;

if (!prop->value) @@ -1084,6 +1193,14 @@ static int _of_init_opp_table_v2(struct device *dev, if (IS_ERR(opp_np)) return PTR_ERR(opp_np);

+ dev_opp = _managed_opp(opp_np); + if (dev_opp) { + /* OPPs are already managed */ + if (!_add_list_dev(dev, dev_opp)) + ret = -ENOMEM; + goto put_opp_np; + } + /* We have opp-list node now, iterate over it and add OPPs */ for_each_available_child_of_node(opp_np, np) { count++; @@ -1100,8 +1217,19 @@ static int _of_init_opp_table_v2(struct device *dev, if (WARN_ON(!count)) goto put_opp_np;

- if (ret) + if (!ret) { + if (!dev_opp) { + dev_opp = _find_device_opp(dev); + if (WARN_ON(!dev_opp)) + goto put_opp_np; + } + + dev_opp->np = opp_np; + if (of_get_property(opp_np, "opp-shared", NULL)) + dev_opp->shared_opp = true; + } else { of_free_opp_table(dev); + }

put_opp_np: of_node_put(opp_np);

With "operating-points-v2" bindings, its possible to specify the OPP to which the device must be switched, before suspending.

This patch adds support for getting that information.

Signed-off-by: Viresh Kumar viresh.kumar@linaro.org --- drivers/base/power/opp.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+)

diff --git a/drivers/base/power/opp.c b/drivers/base/power/opp.c index 6b554e417b1f..0022453e4b60 100644 --- a/drivers/base/power/opp.c +++ b/drivers/base/power/opp.c @@ -137,6 +137,7 @@ struct device_opp { struct device_node *np; unsigned long clock_latency_ns_max; bool shared_opp; + struct dev_pm_opp *suspend_opp; };

/* @@ -1218,6 +1219,8 @@ static int _of_init_opp_table_v2(struct device *dev, goto put_opp_np;

if (!ret) { + const phandle *handle; + if (!dev_opp) { dev_opp = _find_device_opp(dev); if (WARN_ON(!dev_opp)) @@ -1227,6 +1230,25 @@ static int _of_init_opp_table_v2(struct device *dev, dev_opp->np = opp_np; if (of_get_property(opp_np, "opp-shared", NULL)) dev_opp->shared_opp = true; + + /* OPP to select on device suspend */ + handle = of_get_property(opp_np, "opp-suspend", NULL); + if (handle) { + struct device_node *suspend_opp_np; + struct dev_pm_opp *opp; + + suspend_opp_np = of_find_node_by_phandle(be32_to_cpup(handle)); + + list_for_each_entry_rcu(opp, &dev_opp->opp_list, node) + if (opp->np == suspend_opp_np) { + dev_opp->suspend_opp = opp; + break; + } + + if (!dev_opp->suspend_opp) + dev_err(dev, "%s: Invalid opp-suspend\n", + __func__); + } } else { of_free_opp_table(dev); }

Support for parsing operating-points-v2 bindings is in place now, lets modify cpufreq-dt driver to use them.

For backward compatibility we will continue to support earlier bindings. Special handling for that is required, to make sure OPPs are initialized for all the CPUs.

Signed-off-by: Viresh Kumar viresh.kumar@linaro.org --- drivers/cpufreq/cpufreq-dt.c | 58 +++++++++++++++++++++++++++++++++++--------- 1 file changed, 47 insertions(+), 11 deletions(-)

diff --git a/drivers/cpufreq/cpufreq-dt.c b/drivers/cpufreq/cpufreq-dt.c index bab67db54b7e..f7bb2976059a 100644 --- a/drivers/cpufreq/cpufreq-dt.c +++ b/drivers/cpufreq/cpufreq-dt.c @@ -184,7 +184,6 @@ static int allocate_resources(int cpu, struct device **cdev,

static int cpufreq_init(struct cpufreq_policy *policy) { - struct cpufreq_dt_platform_data *pd; struct cpufreq_frequency_table *freq_table; struct device_node *np; struct private_data *priv; @@ -192,7 +191,8 @@ static int cpufreq_init(struct cpufreq_policy *policy) struct regulator *cpu_reg; struct clk *cpu_clk; unsigned long min_uV = ~0, max_uV = 0; - unsigned int transition_latency; + unsigned int transition_latency = 0; + bool need_update = false; int ret;

ret = allocate_resources(policy->cpu, &cpu_dev, &cpu_reg, &cpu_clk); @@ -208,8 +208,47 @@ static int cpufreq_init(struct cpufreq_policy *policy) goto out_put_reg_clk; }

- /* OPPs might be populated at runtime, don't check for error here */ - of_init_opp_table(cpu_dev); + /* Get OPP-sharing information from "operating-points-v2" bindings */ + ret = of_get_cpus_sharing_opps(cpu_dev, policy->cpus); + if (ret) { + /* + * operating-points-v2 not supported, fallback to old method of + * finding shared-OPPs for backward compatibility. + */ + if (ret == -ENOENT) + need_update = true; + else + goto out_node_put; + } + + /* + * Initialize OPP tables for all policy->cpus. They will be shared by + * all CPUs which have marked their CPUs shared with OPP bindings. + * + * For platforms not using operating-points-v2 bindings, we do this + * before updating policy->cpus. Otherwise, we will end up creating + * duplicate OPPs for policy->cpus. + * + * OPPs might be populated at runtime, don't check for error here + */ + of_cpumask_init_opp_table(policy->cpus); + + if (need_update) { + struct cpufreq_dt_platform_data *pd = cpufreq_get_driver_data(); + + if (!pd || !pd->independent_clocks) + cpumask_setall(policy->cpus); + + /* + * OPP tables are initialized only for policy->cpu, do it for + * others as well. + */ + set_cpus_sharing_opps(cpu_dev, policy->cpus); + + of_property_read_u32(np, "clock-latency", &transition_latency); + } else { + transition_latency = dev_pm_opp_get_max_clock_latency(cpu_dev); + }

/* * But we need OPP table to function so if it is not there let's @@ -230,7 +269,7 @@ static int cpufreq_init(struct cpufreq_policy *policy)

of_property_read_u32(np, "voltage-tolerance", &priv->voltage_tolerance);

- if (of_property_read_u32(np, "clock-latency", &transition_latency)) + if (!transition_latency) transition_latency = CPUFREQ_ETERNAL;

if (!IS_ERR(cpu_reg)) { @@ -293,10 +332,6 @@ static int cpufreq_init(struct cpufreq_policy *policy)

policy->cpuinfo.transition_latency = transition_latency;

- pd = cpufreq_get_driver_data(); - if (!pd || !pd->independent_clocks) - cpumask_setall(policy->cpus); - of_node_put(np);

return 0; @@ -306,7 +341,8 @@ static int cpufreq_init(struct cpufreq_policy *policy) out_free_priv: kfree(priv); out_free_opp: - of_free_opp_table(cpu_dev); + of_cpumask_free_opp_table(policy->cpus); +out_node_put: of_node_put(np); out_put_reg_clk: clk_put(cpu_clk); @@ -322,7 +358,7 @@ static int cpufreq_exit(struct cpufreq_policy *policy)

cpufreq_cooling_unregister(priv->cdev); dev_pm_opp_free_cpufreq_table(priv->cpu_dev, &policy->freq_table); - of_free_opp_table(priv->cpu_dev); + of_cpumask_free_opp_table(policy->related_cpus); clk_put(policy->clk); if (!IS_ERR(priv->cpu_reg)) regulator_put(priv->cpu_reg);