diff options
Diffstat (limited to 'drivers/interconnect/core.c')
| -rw-r--r-- | drivers/interconnect/core.c | 84 |
1 files changed, 81 insertions, 3 deletions
diff --git a/drivers/interconnect/core.c b/drivers/interconnect/core.c index 5fac448c28fd..dfab160ca529 100644 --- a/drivers/interconnect/core.c +++ b/drivers/interconnect/core.c @@ -28,6 +28,7 @@ static LIST_HEAD(icc_providers); static int providers_count; static bool synced_state; static DEFINE_MUTEX(icc_lock); +static DEFINE_MUTEX(icc_bw_lock); static struct dentry *icc_debugfs_dir; static void icc_summary_show_one(struct seq_file *s, struct icc_node *n) @@ -147,6 +148,21 @@ static struct icc_node *node_find(const int id) return idr_find(&icc_idr, id); } +static struct icc_node *node_find_by_name(const char *name) +{ + struct icc_provider *provider; + struct icc_node *n; + + list_for_each_entry(provider, &icc_providers, provider_list) { + list_for_each_entry(n, &provider->nodes, node_list) { + if (!strcmp(n->name, name)) + return n; + } + } + + return NULL; +} + static struct icc_path *path_init(struct device *dev, struct icc_node *dst, ssize_t num_nodes) { @@ -562,6 +578,54 @@ struct icc_path *of_icc_get(struct device *dev, const char *name) EXPORT_SYMBOL_GPL(of_icc_get); /** + * icc_get() - get a path handle between two endpoints + * @dev: device pointer for the consumer device + * @src: source node name + * @dst: destination node name + * + * This function will search for a path between two endpoints and return an + * icc_path handle on success. Use icc_put() to release constraints when they + * are not needed anymore. + * + * Return: icc_path pointer on success or ERR_PTR() on error. NULL is returned + * when the API is disabled. + */ +struct icc_path *icc_get(struct device *dev, const char *src, const char *dst) +{ + struct icc_node *src_node, *dst_node; + struct icc_path *path = ERR_PTR(-EPROBE_DEFER); + + mutex_lock(&icc_lock); + + src_node = node_find_by_name(src); + if (!src_node) { + dev_err(dev, "%s: invalid src=%s\n", __func__, src); + goto out; + } + + dst_node = node_find_by_name(dst); + if (!dst_node) { + dev_err(dev, "%s: invalid dst=%s\n", __func__, dst); + goto out; + } + + path = path_find(dev, src_node, dst_node); + if (IS_ERR(path)) { + dev_err(dev, "%s: invalid path=%ld\n", __func__, PTR_ERR(path)); + goto out; + } + + path->name = kasprintf(GFP_KERNEL, "%s-%s", src_node->name, dst_node->name); + if (!path->name) { + kfree(path); + path = ERR_PTR(-ENOMEM); + } +out: + mutex_unlock(&icc_lock); + return path; +} + +/** * icc_set_tag() - set an optional tag on a path * @path: the path we want to tag * @tag: the tag value @@ -631,7 +695,7 @@ int icc_set_bw(struct icc_path *path, u32 avg_bw, u32 peak_bw) if (WARN_ON(IS_ERR(path) || !path->num_nodes)) return -EINVAL; - mutex_lock(&icc_lock); + mutex_lock(&icc_bw_lock); old_avg = path->reqs[0].avg_bw; old_peak = path->reqs[0].peak_bw; @@ -663,7 +727,7 @@ int icc_set_bw(struct icc_path *path, u32 avg_bw, u32 peak_bw) apply_constraints(path); } - mutex_unlock(&icc_lock); + mutex_unlock(&icc_bw_lock); trace_icc_set_bw_end(path, ret); @@ -872,6 +936,7 @@ void icc_node_add(struct icc_node *node, struct icc_provider *provider) return; mutex_lock(&icc_lock); + mutex_lock(&icc_bw_lock); node->provider = provider; list_add_tail(&node->node_list, &provider->nodes); @@ -900,6 +965,7 @@ void icc_node_add(struct icc_node *node, struct icc_provider *provider) node->avg_bw = 0; node->peak_bw = 0; + mutex_unlock(&icc_bw_lock); mutex_unlock(&icc_lock); } EXPORT_SYMBOL_GPL(icc_node_add); @@ -1025,6 +1091,7 @@ void icc_sync_state(struct device *dev) return; mutex_lock(&icc_lock); + mutex_lock(&icc_bw_lock); synced_state = true; list_for_each_entry(p, &icc_providers, provider_list) { dev_dbg(p->dev, "interconnect provider is in synced state\n"); @@ -1037,13 +1104,21 @@ void icc_sync_state(struct device *dev) } } } + mutex_unlock(&icc_bw_lock); mutex_unlock(&icc_lock); } EXPORT_SYMBOL_GPL(icc_sync_state); static int __init icc_init(void) { - struct device_node *root = of_find_node_by_path("/"); + struct device_node *root; + + /* Teach lockdep about lock ordering wrt. shrinker: */ + fs_reclaim_acquire(GFP_KERNEL); + might_lock(&icc_bw_lock); + fs_reclaim_release(GFP_KERNEL); + + root = of_find_node_by_path("/"); providers_count = of_count_icc_providers(root); of_node_put(root); @@ -1053,6 +1128,9 @@ static int __init icc_init(void) icc_debugfs_dir, NULL, &icc_summary_fops); debugfs_create_file("interconnect_graph", 0444, icc_debugfs_dir, NULL, &icc_graph_fops); + + icc_debugfs_client_init(icc_debugfs_dir); + return 0; } |