diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/gpu/host1x/bus.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/gpu/host1x/bus.c')
-rw-r--r-- | drivers/gpu/host1x/bus.c | 984 |
1 files changed, 984 insertions, 0 deletions
diff --git a/drivers/gpu/host1x/bus.c b/drivers/gpu/host1x/bus.c new file mode 100644 index 000000000..bdee16a0b --- /dev/null +++ b/drivers/gpu/host1x/bus.c @@ -0,0 +1,984 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2012 Avionic Design GmbH + * Copyright (C) 2012-2013, NVIDIA Corporation + */ + +#include <linux/debugfs.h> +#include <linux/dma-mapping.h> +#include <linux/host1x.h> +#include <linux/of.h> +#include <linux/seq_file.h> +#include <linux/slab.h> +#include <linux/of_device.h> + +#include "bus.h" +#include "dev.h" + +static DEFINE_MUTEX(clients_lock); +static LIST_HEAD(clients); + +static DEFINE_MUTEX(drivers_lock); +static LIST_HEAD(drivers); + +static DEFINE_MUTEX(devices_lock); +static LIST_HEAD(devices); + +struct host1x_subdev { + struct host1x_client *client; + struct device_node *np; + struct list_head list; +}; + +/** + * host1x_subdev_add() - add a new subdevice with an associated device node + * @device: host1x device to add the subdevice to + * @driver: host1x driver containing the subdevices + * @np: device node + */ +static int host1x_subdev_add(struct host1x_device *device, + struct host1x_driver *driver, + struct device_node *np) +{ + struct host1x_subdev *subdev; + struct device_node *child; + int err; + + subdev = kzalloc(sizeof(*subdev), GFP_KERNEL); + if (!subdev) + return -ENOMEM; + + INIT_LIST_HEAD(&subdev->list); + subdev->np = of_node_get(np); + + mutex_lock(&device->subdevs_lock); + list_add_tail(&subdev->list, &device->subdevs); + mutex_unlock(&device->subdevs_lock); + + /* recursively add children */ + for_each_child_of_node(np, child) { + if (of_match_node(driver->subdevs, child) && + of_device_is_available(child)) { + err = host1x_subdev_add(device, driver, child); + if (err < 0) { + /* XXX cleanup? */ + of_node_put(child); + return err; + } + } + } + + return 0; +} + +/** + * host1x_subdev_del() - remove subdevice + * @subdev: subdevice to remove + */ +static void host1x_subdev_del(struct host1x_subdev *subdev) +{ + list_del(&subdev->list); + of_node_put(subdev->np); + kfree(subdev); +} + +/** + * host1x_device_parse_dt() - scan device tree and add matching subdevices + * @device: host1x logical device + * @driver: host1x driver + */ +static int host1x_device_parse_dt(struct host1x_device *device, + struct host1x_driver *driver) +{ + struct device_node *np; + int err; + + for_each_child_of_node(device->dev.parent->of_node, np) { + if (of_match_node(driver->subdevs, np) && + of_device_is_available(np)) { + err = host1x_subdev_add(device, driver, np); + if (err < 0) { + of_node_put(np); + return err; + } + } + } + + return 0; +} + +static void host1x_subdev_register(struct host1x_device *device, + struct host1x_subdev *subdev, + struct host1x_client *client) +{ + int err; + + /* + * Move the subdevice to the list of active (registered) subdevices + * and associate it with a client. At the same time, associate the + * client with its parent device. + */ + mutex_lock(&device->subdevs_lock); + mutex_lock(&device->clients_lock); + list_move_tail(&client->list, &device->clients); + list_move_tail(&subdev->list, &device->active); + client->host = &device->dev; + subdev->client = client; + mutex_unlock(&device->clients_lock); + mutex_unlock(&device->subdevs_lock); + + if (list_empty(&device->subdevs)) { + err = device_add(&device->dev); + if (err < 0) + dev_err(&device->dev, "failed to add: %d\n", err); + else + device->registered = true; + } +} + +static void __host1x_subdev_unregister(struct host1x_device *device, + struct host1x_subdev *subdev) +{ + struct host1x_client *client = subdev->client; + + /* + * If all subdevices have been activated, we're about to remove the + * first active subdevice, so unload the driver first. + */ + if (list_empty(&device->subdevs)) { + if (device->registered) { + device->registered = false; + device_del(&device->dev); + } + } + + /* + * Move the subdevice back to the list of idle subdevices and remove + * it from list of clients. + */ + mutex_lock(&device->clients_lock); + subdev->client = NULL; + client->host = NULL; + list_move_tail(&subdev->list, &device->subdevs); + /* + * XXX: Perhaps don't do this here, but rather explicitly remove it + * when the device is about to be deleted. + * + * This is somewhat complicated by the fact that this function is + * used to remove the subdevice when a client is unregistered but + * also when the composite device is about to be removed. + */ + list_del_init(&client->list); + mutex_unlock(&device->clients_lock); +} + +static void host1x_subdev_unregister(struct host1x_device *device, + struct host1x_subdev *subdev) +{ + mutex_lock(&device->subdevs_lock); + __host1x_subdev_unregister(device, subdev); + mutex_unlock(&device->subdevs_lock); +} + +/** + * host1x_device_init() - initialize a host1x logical device + * @device: host1x logical device + * + * The driver for the host1x logical device can call this during execution of + * its &host1x_driver.probe implementation to initialize each of its clients. + * The client drivers access the subsystem specific driver data using the + * &host1x_client.parent field and driver data associated with it (usually by + * calling dev_get_drvdata()). + */ +int host1x_device_init(struct host1x_device *device) +{ + struct host1x_client *client; + int err; + + mutex_lock(&device->clients_lock); + + list_for_each_entry(client, &device->clients, list) { + if (client->ops && client->ops->early_init) { + err = client->ops->early_init(client); + if (err < 0) { + dev_err(&device->dev, "failed to early initialize %s: %d\n", + dev_name(client->dev), err); + goto teardown_late; + } + } + } + + list_for_each_entry(client, &device->clients, list) { + if (client->ops && client->ops->init) { + err = client->ops->init(client); + if (err < 0) { + dev_err(&device->dev, + "failed to initialize %s: %d\n", + dev_name(client->dev), err); + goto teardown; + } + } + } + + mutex_unlock(&device->clients_lock); + + return 0; + +teardown: + list_for_each_entry_continue_reverse(client, &device->clients, list) + if (client->ops->exit) + client->ops->exit(client); + + /* reset client to end of list for late teardown */ + client = list_entry(&device->clients, struct host1x_client, list); + +teardown_late: + list_for_each_entry_continue_reverse(client, &device->clients, list) + if (client->ops->late_exit) + client->ops->late_exit(client); + + mutex_unlock(&device->clients_lock); + return err; +} +EXPORT_SYMBOL(host1x_device_init); + +/** + * host1x_device_exit() - uninitialize host1x logical device + * @device: host1x logical device + * + * When the driver for a host1x logical device is unloaded, it can call this + * function to tear down each of its clients. Typically this is done after a + * subsystem-specific data structure is removed and the functionality can no + * longer be used. + */ +int host1x_device_exit(struct host1x_device *device) +{ + struct host1x_client *client; + int err; + + mutex_lock(&device->clients_lock); + + list_for_each_entry_reverse(client, &device->clients, list) { + if (client->ops && client->ops->exit) { + err = client->ops->exit(client); + if (err < 0) { + dev_err(&device->dev, + "failed to cleanup %s: %d\n", + dev_name(client->dev), err); + mutex_unlock(&device->clients_lock); + return err; + } + } + } + + list_for_each_entry_reverse(client, &device->clients, list) { + if (client->ops && client->ops->late_exit) { + err = client->ops->late_exit(client); + if (err < 0) { + dev_err(&device->dev, "failed to late cleanup %s: %d\n", + dev_name(client->dev), err); + mutex_unlock(&device->clients_lock); + return err; + } + } + } + + mutex_unlock(&device->clients_lock); + + return 0; +} +EXPORT_SYMBOL(host1x_device_exit); + +static int host1x_add_client(struct host1x *host1x, + struct host1x_client *client) +{ + struct host1x_device *device; + struct host1x_subdev *subdev; + + mutex_lock(&host1x->devices_lock); + + list_for_each_entry(device, &host1x->devices, list) { + list_for_each_entry(subdev, &device->subdevs, list) { + if (subdev->np == client->dev->of_node) { + host1x_subdev_register(device, subdev, client); + mutex_unlock(&host1x->devices_lock); + return 0; + } + } + } + + mutex_unlock(&host1x->devices_lock); + return -ENODEV; +} + +static int host1x_del_client(struct host1x *host1x, + struct host1x_client *client) +{ + struct host1x_device *device, *dt; + struct host1x_subdev *subdev; + + mutex_lock(&host1x->devices_lock); + + list_for_each_entry_safe(device, dt, &host1x->devices, list) { + list_for_each_entry(subdev, &device->active, list) { + if (subdev->client == client) { + host1x_subdev_unregister(device, subdev); + mutex_unlock(&host1x->devices_lock); + return 0; + } + } + } + + mutex_unlock(&host1x->devices_lock); + return -ENODEV; +} + +static int host1x_device_match(struct device *dev, struct device_driver *drv) +{ + return strcmp(dev_name(dev), drv->name) == 0; +} + +static int host1x_device_uevent(struct device *dev, + struct kobj_uevent_env *env) +{ + struct device_node *np = dev->parent->of_node; + unsigned int count = 0; + struct property *p; + const char *compat; + + /* + * This duplicates most of of_device_uevent(), but the latter cannot + * be called from modules and operates on dev->of_node, which is not + * available in this case. + * + * Note that this is really only needed for backwards compatibility + * with libdrm, which parses this information from sysfs and will + * fail if it can't find the OF_FULLNAME, specifically. + */ + add_uevent_var(env, "OF_NAME=%pOFn", np); + add_uevent_var(env, "OF_FULLNAME=%pOF", np); + + of_property_for_each_string(np, "compatible", p, compat) { + add_uevent_var(env, "OF_COMPATIBLE_%u=%s", count, compat); + count++; + } + + add_uevent_var(env, "OF_COMPATIBLE_N=%u", count); + + return 0; +} + +static int host1x_dma_configure(struct device *dev) +{ + return of_dma_configure(dev, dev->of_node, true); +} + +static const struct dev_pm_ops host1x_device_pm_ops = { + .suspend = pm_generic_suspend, + .resume = pm_generic_resume, + .freeze = pm_generic_freeze, + .thaw = pm_generic_thaw, + .poweroff = pm_generic_poweroff, + .restore = pm_generic_restore, +}; + +struct bus_type host1x_bus_type = { + .name = "host1x", + .match = host1x_device_match, + .uevent = host1x_device_uevent, + .dma_configure = host1x_dma_configure, + .pm = &host1x_device_pm_ops, +}; + +static void __host1x_device_del(struct host1x_device *device) +{ + struct host1x_subdev *subdev, *sd; + struct host1x_client *client, *cl; + + mutex_lock(&device->subdevs_lock); + + /* unregister subdevices */ + list_for_each_entry_safe(subdev, sd, &device->active, list) { + /* + * host1x_subdev_unregister() will remove the client from + * any lists, so we'll need to manually add it back to the + * list of idle clients. + * + * XXX: Alternatively, perhaps don't remove the client from + * any lists in host1x_subdev_unregister() and instead do + * that explicitly from host1x_unregister_client()? + */ + client = subdev->client; + + __host1x_subdev_unregister(device, subdev); + + /* add the client to the list of idle clients */ + mutex_lock(&clients_lock); + list_add_tail(&client->list, &clients); + mutex_unlock(&clients_lock); + } + + /* remove subdevices */ + list_for_each_entry_safe(subdev, sd, &device->subdevs, list) + host1x_subdev_del(subdev); + + mutex_unlock(&device->subdevs_lock); + + /* move clients to idle list */ + mutex_lock(&clients_lock); + mutex_lock(&device->clients_lock); + + list_for_each_entry_safe(client, cl, &device->clients, list) + list_move_tail(&client->list, &clients); + + mutex_unlock(&device->clients_lock); + mutex_unlock(&clients_lock); + + /* finally remove the device */ + list_del_init(&device->list); +} + +static void host1x_device_release(struct device *dev) +{ + struct host1x_device *device = to_host1x_device(dev); + + __host1x_device_del(device); + kfree(device); +} + +static int host1x_device_add(struct host1x *host1x, + struct host1x_driver *driver) +{ + struct host1x_client *client, *tmp; + struct host1x_subdev *subdev; + struct host1x_device *device; + int err; + + device = kzalloc(sizeof(*device), GFP_KERNEL); + if (!device) + return -ENOMEM; + + device_initialize(&device->dev); + + mutex_init(&device->subdevs_lock); + INIT_LIST_HEAD(&device->subdevs); + INIT_LIST_HEAD(&device->active); + mutex_init(&device->clients_lock); + INIT_LIST_HEAD(&device->clients); + INIT_LIST_HEAD(&device->list); + device->driver = driver; + + device->dev.coherent_dma_mask = host1x->dev->coherent_dma_mask; + device->dev.dma_mask = &device->dev.coherent_dma_mask; + dev_set_name(&device->dev, "%s", driver->driver.name); + device->dev.release = host1x_device_release; + device->dev.bus = &host1x_bus_type; + device->dev.parent = host1x->dev; + + of_dma_configure(&device->dev, host1x->dev->of_node, true); + + device->dev.dma_parms = &device->dma_parms; + dma_set_max_seg_size(&device->dev, UINT_MAX); + + err = host1x_device_parse_dt(device, driver); + if (err < 0) { + kfree(device); + return err; + } + + list_add_tail(&device->list, &host1x->devices); + + mutex_lock(&clients_lock); + + list_for_each_entry_safe(client, tmp, &clients, list) { + list_for_each_entry(subdev, &device->subdevs, list) { + if (subdev->np == client->dev->of_node) { + host1x_subdev_register(device, subdev, client); + break; + } + } + } + + mutex_unlock(&clients_lock); + + return 0; +} + +/* + * Removes a device by first unregistering any subdevices and then removing + * itself from the list of devices. + * + * This function must be called with the host1x->devices_lock held. + */ +static void host1x_device_del(struct host1x *host1x, + struct host1x_device *device) +{ + if (device->registered) { + device->registered = false; + device_del(&device->dev); + } + + put_device(&device->dev); +} + +static void host1x_attach_driver(struct host1x *host1x, + struct host1x_driver *driver) +{ + struct host1x_device *device; + int err; + + mutex_lock(&host1x->devices_lock); + + list_for_each_entry(device, &host1x->devices, list) { + if (device->driver == driver) { + mutex_unlock(&host1x->devices_lock); + return; + } + } + + err = host1x_device_add(host1x, driver); + if (err < 0) + dev_err(host1x->dev, "failed to allocate device: %d\n", err); + + mutex_unlock(&host1x->devices_lock); +} + +static void host1x_detach_driver(struct host1x *host1x, + struct host1x_driver *driver) +{ + struct host1x_device *device, *tmp; + + mutex_lock(&host1x->devices_lock); + + list_for_each_entry_safe(device, tmp, &host1x->devices, list) + if (device->driver == driver) + host1x_device_del(host1x, device); + + mutex_unlock(&host1x->devices_lock); +} + +static int host1x_devices_show(struct seq_file *s, void *data) +{ + struct host1x *host1x = s->private; + struct host1x_device *device; + + mutex_lock(&host1x->devices_lock); + + list_for_each_entry(device, &host1x->devices, list) { + struct host1x_subdev *subdev; + + seq_printf(s, "%s\n", dev_name(&device->dev)); + + mutex_lock(&device->subdevs_lock); + + list_for_each_entry(subdev, &device->active, list) + seq_printf(s, " %pOFf: %s\n", subdev->np, + dev_name(subdev->client->dev)); + + list_for_each_entry(subdev, &device->subdevs, list) + seq_printf(s, " %pOFf:\n", subdev->np); + + mutex_unlock(&device->subdevs_lock); + } + + mutex_unlock(&host1x->devices_lock); + + return 0; +} +DEFINE_SHOW_ATTRIBUTE(host1x_devices); + +/** + * host1x_register() - register a host1x controller + * @host1x: host1x controller + * + * The host1x controller driver uses this to register a host1x controller with + * the infrastructure. Note that all Tegra SoC generations have only ever come + * with a single host1x instance, so this function is somewhat academic. + */ +int host1x_register(struct host1x *host1x) +{ + struct host1x_driver *driver; + + mutex_lock(&devices_lock); + list_add_tail(&host1x->list, &devices); + mutex_unlock(&devices_lock); + + mutex_lock(&drivers_lock); + + list_for_each_entry(driver, &drivers, list) + host1x_attach_driver(host1x, driver); + + mutex_unlock(&drivers_lock); + + debugfs_create_file("devices", S_IRUGO, host1x->debugfs, host1x, + &host1x_devices_fops); + + return 0; +} + +/** + * host1x_unregister() - unregister a host1x controller + * @host1x: host1x controller + * + * The host1x controller driver uses this to remove a host1x controller from + * the infrastructure. + */ +int host1x_unregister(struct host1x *host1x) +{ + struct host1x_driver *driver; + + mutex_lock(&drivers_lock); + + list_for_each_entry(driver, &drivers, list) + host1x_detach_driver(host1x, driver); + + mutex_unlock(&drivers_lock); + + mutex_lock(&devices_lock); + list_del_init(&host1x->list); + mutex_unlock(&devices_lock); + + return 0; +} + +static int host1x_device_probe(struct device *dev) +{ + struct host1x_driver *driver = to_host1x_driver(dev->driver); + struct host1x_device *device = to_host1x_device(dev); + + if (driver->probe) + return driver->probe(device); + + return 0; +} + +static int host1x_device_remove(struct device *dev) +{ + struct host1x_driver *driver = to_host1x_driver(dev->driver); + struct host1x_device *device = to_host1x_device(dev); + + if (driver->remove) + return driver->remove(device); + + return 0; +} + +static void host1x_device_shutdown(struct device *dev) +{ + struct host1x_driver *driver = to_host1x_driver(dev->driver); + struct host1x_device *device = to_host1x_device(dev); + + if (driver->shutdown) + driver->shutdown(device); +} + +/** + * host1x_driver_register_full() - register a host1x driver + * @driver: host1x driver + * @owner: owner module + * + * Drivers for host1x logical devices call this function to register a driver + * with the infrastructure. Note that since these drive logical devices, the + * registration of the driver actually triggers tho logical device creation. + * A logical device will be created for each host1x instance. + */ +int host1x_driver_register_full(struct host1x_driver *driver, + struct module *owner) +{ + struct host1x *host1x; + + INIT_LIST_HEAD(&driver->list); + + mutex_lock(&drivers_lock); + list_add_tail(&driver->list, &drivers); + mutex_unlock(&drivers_lock); + + mutex_lock(&devices_lock); + + list_for_each_entry(host1x, &devices, list) + host1x_attach_driver(host1x, driver); + + mutex_unlock(&devices_lock); + + driver->driver.bus = &host1x_bus_type; + driver->driver.owner = owner; + driver->driver.probe = host1x_device_probe; + driver->driver.remove = host1x_device_remove; + driver->driver.shutdown = host1x_device_shutdown; + + return driver_register(&driver->driver); +} +EXPORT_SYMBOL(host1x_driver_register_full); + +/** + * host1x_driver_unregister() - unregister a host1x driver + * @driver: host1x driver + * + * Unbinds the driver from each of the host1x logical devices that it is + * bound to, effectively removing the subsystem devices that they represent. + */ +void host1x_driver_unregister(struct host1x_driver *driver) +{ + struct host1x *host1x; + + driver_unregister(&driver->driver); + + mutex_lock(&devices_lock); + + list_for_each_entry(host1x, &devices, list) + host1x_detach_driver(host1x, driver); + + mutex_unlock(&devices_lock); + + mutex_lock(&drivers_lock); + list_del_init(&driver->list); + mutex_unlock(&drivers_lock); +} +EXPORT_SYMBOL(host1x_driver_unregister); + +/** + * __host1x_client_init() - initialize a host1x client + * @client: host1x client + * @key: lock class key for the client-specific mutex + */ +void __host1x_client_init(struct host1x_client *client, struct lock_class_key *key) +{ + host1x_bo_cache_init(&client->cache); + INIT_LIST_HEAD(&client->list); + __mutex_init(&client->lock, "host1x client lock", key); + client->usecount = 0; +} +EXPORT_SYMBOL(__host1x_client_init); + +/** + * host1x_client_exit() - uninitialize a host1x client + * @client: host1x client + */ +void host1x_client_exit(struct host1x_client *client) +{ + mutex_destroy(&client->lock); +} +EXPORT_SYMBOL(host1x_client_exit); + +/** + * __host1x_client_register() - register a host1x client + * @client: host1x client + * + * Registers a host1x client with each host1x controller instance. Note that + * each client will only match their parent host1x controller and will only be + * associated with that instance. Once all clients have been registered with + * their parent host1x controller, the infrastructure will set up the logical + * device and call host1x_device_init(), which will in turn call each client's + * &host1x_client_ops.init implementation. + */ +int __host1x_client_register(struct host1x_client *client) +{ + struct host1x *host1x; + int err; + + mutex_lock(&devices_lock); + + list_for_each_entry(host1x, &devices, list) { + err = host1x_add_client(host1x, client); + if (!err) { + mutex_unlock(&devices_lock); + return 0; + } + } + + mutex_unlock(&devices_lock); + + mutex_lock(&clients_lock); + list_add_tail(&client->list, &clients); + mutex_unlock(&clients_lock); + + return 0; +} +EXPORT_SYMBOL(__host1x_client_register); + +/** + * host1x_client_unregister() - unregister a host1x client + * @client: host1x client + * + * Removes a host1x client from its host1x controller instance. If a logical + * device has already been initialized, it will be torn down. + */ +int host1x_client_unregister(struct host1x_client *client) +{ + struct host1x_client *c; + struct host1x *host1x; + int err; + + mutex_lock(&devices_lock); + + list_for_each_entry(host1x, &devices, list) { + err = host1x_del_client(host1x, client); + if (!err) { + mutex_unlock(&devices_lock); + return 0; + } + } + + mutex_unlock(&devices_lock); + mutex_lock(&clients_lock); + + list_for_each_entry(c, &clients, list) { + if (c == client) { + list_del_init(&c->list); + break; + } + } + + mutex_unlock(&clients_lock); + + host1x_bo_cache_destroy(&client->cache); + + return 0; +} +EXPORT_SYMBOL(host1x_client_unregister); + +int host1x_client_suspend(struct host1x_client *client) +{ + int err = 0; + + mutex_lock(&client->lock); + + if (client->usecount == 1) { + if (client->ops && client->ops->suspend) { + err = client->ops->suspend(client); + if (err < 0) + goto unlock; + } + } + + client->usecount--; + dev_dbg(client->dev, "use count: %u\n", client->usecount); + + if (client->parent) { + err = host1x_client_suspend(client->parent); + if (err < 0) + goto resume; + } + + goto unlock; + +resume: + if (client->usecount == 0) + if (client->ops && client->ops->resume) + client->ops->resume(client); + + client->usecount++; +unlock: + mutex_unlock(&client->lock); + return err; +} +EXPORT_SYMBOL(host1x_client_suspend); + +int host1x_client_resume(struct host1x_client *client) +{ + int err = 0; + + mutex_lock(&client->lock); + + if (client->parent) { + err = host1x_client_resume(client->parent); + if (err < 0) + goto unlock; + } + + if (client->usecount == 0) { + if (client->ops && client->ops->resume) { + err = client->ops->resume(client); + if (err < 0) + goto suspend; + } + } + + client->usecount++; + dev_dbg(client->dev, "use count: %u\n", client->usecount); + + goto unlock; + +suspend: + if (client->parent) + host1x_client_suspend(client->parent); +unlock: + mutex_unlock(&client->lock); + return err; +} +EXPORT_SYMBOL(host1x_client_resume); + +struct host1x_bo_mapping *host1x_bo_pin(struct device *dev, struct host1x_bo *bo, + enum dma_data_direction dir, + struct host1x_bo_cache *cache) +{ + struct host1x_bo_mapping *mapping; + + if (cache) { + mutex_lock(&cache->lock); + + list_for_each_entry(mapping, &cache->mappings, entry) { + if (mapping->bo == bo && mapping->direction == dir) { + kref_get(&mapping->ref); + goto unlock; + } + } + } + + mapping = bo->ops->pin(dev, bo, dir); + if (IS_ERR(mapping)) + goto unlock; + + spin_lock(&mapping->bo->lock); + list_add_tail(&mapping->list, &bo->mappings); + spin_unlock(&mapping->bo->lock); + + if (cache) { + INIT_LIST_HEAD(&mapping->entry); + mapping->cache = cache; + + list_add_tail(&mapping->entry, &cache->mappings); + + /* bump reference count to track the copy in the cache */ + kref_get(&mapping->ref); + } + +unlock: + if (cache) + mutex_unlock(&cache->lock); + + return mapping; +} +EXPORT_SYMBOL(host1x_bo_pin); + +static void __host1x_bo_unpin(struct kref *ref) +{ + struct host1x_bo_mapping *mapping = to_host1x_bo_mapping(ref); + + /* + * When the last reference of the mapping goes away, make sure to remove the mapping from + * the cache. + */ + if (mapping->cache) + list_del(&mapping->entry); + + spin_lock(&mapping->bo->lock); + list_del(&mapping->list); + spin_unlock(&mapping->bo->lock); + + mapping->bo->ops->unpin(mapping); +} + +void host1x_bo_unpin(struct host1x_bo_mapping *mapping) +{ + struct host1x_bo_cache *cache = mapping->cache; + + if (cache) + mutex_lock(&cache->lock); + + kref_put(&mapping->ref, __host1x_bo_unpin); + + if (cache) + mutex_unlock(&cache->lock); +} +EXPORT_SYMBOL(host1x_bo_unpin); |