diff options
Diffstat (limited to 'drivers/interconnect/core.c')
| -rw-r--r-- | drivers/interconnect/core.c | 1184 |
1 files changed, 1184 insertions, 0 deletions
diff --git a/drivers/interconnect/core.c b/drivers/interconnect/core.c new file mode 100644 index 000000000..1d9494f64 --- /dev/null +++ b/drivers/interconnect/core.c @@ -0,0 +1,1184 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Interconnect framework core driver + * + * Copyright (c) 2017-2019, Linaro Ltd. + * Author: Georgi Djakov <georgi.djakov@linaro.org> + */ + +#include <linux/debugfs.h> +#include <linux/device.h> +#include <linux/idr.h> +#include <linux/init.h> +#include <linux/interconnect.h> +#include <linux/interconnect-provider.h> +#include <linux/list.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/slab.h> +#include <linux/of.h> +#include <linux/overflow.h> + +#include "internal.h" + +#define CREATE_TRACE_POINTS +#include "trace.h" + +static DEFINE_IDR(icc_idr); +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) +{ + if (!n) + return; + + seq_printf(s, "%-42s %12u %12u\n", + n->name, n->avg_bw, n->peak_bw); +} + +static int icc_summary_show(struct seq_file *s, void *data) +{ + struct icc_provider *provider; + + seq_puts(s, " node tag avg peak\n"); + seq_puts(s, "--------------------------------------------------------------------\n"); + + mutex_lock(&icc_lock); + + list_for_each_entry(provider, &icc_providers, provider_list) { + struct icc_node *n; + + list_for_each_entry(n, &provider->nodes, node_list) { + struct icc_req *r; + + icc_summary_show_one(s, n); + hlist_for_each_entry(r, &n->req_list, req_node) { + u32 avg_bw = 0, peak_bw = 0; + + if (!r->dev) + continue; + + if (r->enabled) { + avg_bw = r->avg_bw; + peak_bw = r->peak_bw; + } + + seq_printf(s, " %-27s %12u %12u %12u\n", + dev_name(r->dev), r->tag, avg_bw, peak_bw); + } + } + } + + mutex_unlock(&icc_lock); + + return 0; +} +DEFINE_SHOW_ATTRIBUTE(icc_summary); + +static void icc_graph_show_link(struct seq_file *s, int level, + struct icc_node *n, struct icc_node *m) +{ + seq_printf(s, "%s\"%d:%s\" -> \"%d:%s\"\n", + level == 2 ? "\t\t" : "\t", + n->id, n->name, m->id, m->name); +} + +static void icc_graph_show_node(struct seq_file *s, struct icc_node *n) +{ + seq_printf(s, "\t\t\"%d:%s\" [label=\"%d:%s", + n->id, n->name, n->id, n->name); + seq_printf(s, "\n\t\t\t|avg_bw=%ukBps", n->avg_bw); + seq_printf(s, "\n\t\t\t|peak_bw=%ukBps", n->peak_bw); + seq_puts(s, "\"]\n"); +} + +static int icc_graph_show(struct seq_file *s, void *data) +{ + struct icc_provider *provider; + struct icc_node *n; + int cluster_index = 0; + int i; + + seq_puts(s, "digraph {\n\trankdir = LR\n\tnode [shape = record]\n"); + mutex_lock(&icc_lock); + + /* draw providers as cluster subgraphs */ + cluster_index = 0; + list_for_each_entry(provider, &icc_providers, provider_list) { + seq_printf(s, "\tsubgraph cluster_%d {\n", ++cluster_index); + if (provider->dev) + seq_printf(s, "\t\tlabel = \"%s\"\n", + dev_name(provider->dev)); + + /* draw nodes */ + list_for_each_entry(n, &provider->nodes, node_list) + icc_graph_show_node(s, n); + + /* draw internal links */ + list_for_each_entry(n, &provider->nodes, node_list) + for (i = 0; i < n->num_links; ++i) + if (n->provider == n->links[i]->provider) + icc_graph_show_link(s, 2, n, + n->links[i]); + + seq_puts(s, "\t}\n"); + } + + /* draw external links */ + list_for_each_entry(provider, &icc_providers, provider_list) + list_for_each_entry(n, &provider->nodes, node_list) + for (i = 0; i < n->num_links; ++i) + if (n->provider != n->links[i]->provider) + icc_graph_show_link(s, 1, n, + n->links[i]); + + mutex_unlock(&icc_lock); + seq_puts(s, "}"); + + return 0; +} +DEFINE_SHOW_ATTRIBUTE(icc_graph); + +static struct icc_node *node_find(const int id) +{ + return idr_find(&icc_idr, id); +} + +static struct icc_path *path_init(struct device *dev, struct icc_node *dst, + ssize_t num_nodes) +{ + struct icc_node *node = dst; + struct icc_path *path; + int i; + + path = kzalloc(struct_size(path, reqs, num_nodes), GFP_KERNEL); + if (!path) + return ERR_PTR(-ENOMEM); + + path->num_nodes = num_nodes; + + for (i = num_nodes - 1; i >= 0; i--) { + node->provider->users++; + hlist_add_head(&path->reqs[i].req_node, &node->req_list); + path->reqs[i].node = node; + path->reqs[i].dev = dev; + path->reqs[i].enabled = true; + /* reference to previous node was saved during path traversal */ + node = node->reverse; + } + + return path; +} + +static struct icc_path *path_find(struct device *dev, struct icc_node *src, + struct icc_node *dst) +{ + struct icc_path *path = ERR_PTR(-EPROBE_DEFER); + struct icc_node *n, *node = NULL; + struct list_head traverse_list; + struct list_head edge_list; + struct list_head visited_list; + size_t i, depth = 1; + bool found = false; + + INIT_LIST_HEAD(&traverse_list); + INIT_LIST_HEAD(&edge_list); + INIT_LIST_HEAD(&visited_list); + + list_add(&src->search_list, &traverse_list); + src->reverse = NULL; + + do { + list_for_each_entry_safe(node, n, &traverse_list, search_list) { + if (node == dst) { + found = true; + list_splice_init(&edge_list, &visited_list); + list_splice_init(&traverse_list, &visited_list); + break; + } + for (i = 0; i < node->num_links; i++) { + struct icc_node *tmp = node->links[i]; + + if (!tmp) { + path = ERR_PTR(-ENOENT); + goto out; + } + + if (tmp->is_traversed) + continue; + + tmp->is_traversed = true; + tmp->reverse = node; + list_add_tail(&tmp->search_list, &edge_list); + } + } + + if (found) + break; + + list_splice_init(&traverse_list, &visited_list); + list_splice_init(&edge_list, &traverse_list); + + /* count the hops including the source */ + depth++; + + } while (!list_empty(&traverse_list)); + +out: + + /* reset the traversed state */ + list_for_each_entry_reverse(n, &visited_list, search_list) + n->is_traversed = false; + + if (found) + path = path_init(dev, dst, depth); + + return path; +} + +/* + * We want the path to honor all bandwidth requests, so the average and peak + * bandwidth requirements from each consumer are aggregated at each node. + * The aggregation is platform specific, so each platform can customize it by + * implementing its own aggregate() function. + */ + +static int aggregate_requests(struct icc_node *node) +{ + struct icc_provider *p = node->provider; + struct icc_req *r; + u32 avg_bw, peak_bw; + + node->avg_bw = 0; + node->peak_bw = 0; + + if (p->pre_aggregate) + p->pre_aggregate(node); + + hlist_for_each_entry(r, &node->req_list, req_node) { + if (r->enabled) { + avg_bw = r->avg_bw; + peak_bw = r->peak_bw; + } else { + avg_bw = 0; + peak_bw = 0; + } + p->aggregate(node, r->tag, avg_bw, peak_bw, + &node->avg_bw, &node->peak_bw); + + /* during boot use the initial bandwidth as a floor value */ + if (!synced_state) { + node->avg_bw = max(node->avg_bw, node->init_avg); + node->peak_bw = max(node->peak_bw, node->init_peak); + } + } + + return 0; +} + +static int apply_constraints(struct icc_path *path) +{ + struct icc_node *next, *prev = NULL; + struct icc_provider *p; + int ret = -EINVAL; + int i; + + for (i = 0; i < path->num_nodes; i++) { + next = path->reqs[i].node; + p = next->provider; + + /* both endpoints should be valid master-slave pairs */ + if (!prev || (p != prev->provider && !p->inter_set)) { + prev = next; + continue; + } + + /* set the constraints */ + ret = p->set(prev, next); + if (ret) + goto out; + + prev = next; + } +out: + return ret; +} + +int icc_std_aggregate(struct icc_node *node, u32 tag, u32 avg_bw, + u32 peak_bw, u32 *agg_avg, u32 *agg_peak) +{ + *agg_avg += avg_bw; + *agg_peak = max(*agg_peak, peak_bw); + + return 0; +} +EXPORT_SYMBOL_GPL(icc_std_aggregate); + +/* of_icc_xlate_onecell() - Translate function using a single index. + * @spec: OF phandle args to map into an interconnect node. + * @data: private data (pointer to struct icc_onecell_data) + * + * This is a generic translate function that can be used to model simple + * interconnect providers that have one device tree node and provide + * multiple interconnect nodes. A single cell is used as an index into + * an array of icc nodes specified in the icc_onecell_data struct when + * registering the provider. + */ +struct icc_node *of_icc_xlate_onecell(struct of_phandle_args *spec, + void *data) +{ + struct icc_onecell_data *icc_data = data; + unsigned int idx = spec->args[0]; + + if (idx >= icc_data->num_nodes) { + pr_err("%s: invalid index %u\n", __func__, idx); + return ERR_PTR(-EINVAL); + } + + return icc_data->nodes[idx]; +} +EXPORT_SYMBOL_GPL(of_icc_xlate_onecell); + +/** + * of_icc_get_from_provider() - Look-up interconnect node + * @spec: OF phandle args to use for look-up + * + * Looks for interconnect provider under the node specified by @spec and if + * found, uses xlate function of the provider to map phandle args to node. + * + * Returns a valid pointer to struct icc_node_data on success or ERR_PTR() + * on failure. + */ +struct icc_node_data *of_icc_get_from_provider(struct of_phandle_args *spec) +{ + struct icc_node *node = ERR_PTR(-EPROBE_DEFER); + struct icc_node_data *data = NULL; + struct icc_provider *provider; + + if (!spec) + return ERR_PTR(-EINVAL); + + mutex_lock(&icc_lock); + list_for_each_entry(provider, &icc_providers, provider_list) { + if (provider->dev->of_node == spec->np) { + if (provider->xlate_extended) { + data = provider->xlate_extended(spec, provider->data); + if (!IS_ERR(data)) { + node = data->node; + break; + } + } else { + node = provider->xlate(spec, provider->data); + if (!IS_ERR(node)) + break; + } + } + } + mutex_unlock(&icc_lock); + + if (!node) + return ERR_PTR(-EINVAL); + + if (IS_ERR(node)) + return ERR_CAST(node); + + if (!data) { + data = kzalloc(sizeof(*data), GFP_KERNEL); + if (!data) + return ERR_PTR(-ENOMEM); + data->node = node; + } + + return data; +} +EXPORT_SYMBOL_GPL(of_icc_get_from_provider); + +static void devm_icc_release(struct device *dev, void *res) +{ + icc_put(*(struct icc_path **)res); +} + +struct icc_path *devm_of_icc_get(struct device *dev, const char *name) +{ + struct icc_path **ptr, *path; + + ptr = devres_alloc(devm_icc_release, sizeof(*ptr), GFP_KERNEL); + if (!ptr) + return ERR_PTR(-ENOMEM); + + path = of_icc_get(dev, name); + if (!IS_ERR(path)) { + *ptr = path; + devres_add(dev, ptr); + } else { + devres_free(ptr); + } + + return path; +} +EXPORT_SYMBOL_GPL(devm_of_icc_get); + +/** + * of_icc_get_by_index() - get a path handle from a DT node based on index + * @dev: device pointer for the consumer device + * @idx: interconnect path index + * + * 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. + * If the interconnect API is disabled, NULL is returned and the consumer + * drivers will still build. Drivers are free to handle this specifically, + * but they don't have to. + * + * Return: icc_path pointer on success or ERR_PTR() on error. NULL is returned + * when the API is disabled or the "interconnects" DT property is missing. + */ +struct icc_path *of_icc_get_by_index(struct device *dev, int idx) +{ + struct icc_path *path; + struct icc_node_data *src_data, *dst_data; + struct device_node *np; + struct of_phandle_args src_args, dst_args; + int ret; + + if (!dev || !dev->of_node) + return ERR_PTR(-ENODEV); + + np = dev->of_node; + + /* + * When the consumer DT node do not have "interconnects" property + * return a NULL path to skip setting constraints. + */ + if (!of_find_property(np, "interconnects", NULL)) + return NULL; + + /* + * We use a combination of phandle and specifier for endpoint. For now + * lets support only global ids and extend this in the future if needed + * without breaking DT compatibility. + */ + ret = of_parse_phandle_with_args(np, "interconnects", + "#interconnect-cells", idx * 2, + &src_args); + if (ret) + return ERR_PTR(ret); + + of_node_put(src_args.np); + + ret = of_parse_phandle_with_args(np, "interconnects", + "#interconnect-cells", idx * 2 + 1, + &dst_args); + if (ret) + return ERR_PTR(ret); + + of_node_put(dst_args.np); + + src_data = of_icc_get_from_provider(&src_args); + + if (IS_ERR(src_data)) { + dev_err_probe(dev, PTR_ERR(src_data), "error finding src node\n"); + return ERR_CAST(src_data); + } + + dst_data = of_icc_get_from_provider(&dst_args); + + if (IS_ERR(dst_data)) { + dev_err_probe(dev, PTR_ERR(dst_data), "error finding dst node\n"); + kfree(src_data); + return ERR_CAST(dst_data); + } + + mutex_lock(&icc_lock); + path = path_find(dev, src_data->node, dst_data->node); + mutex_unlock(&icc_lock); + if (IS_ERR(path)) { + dev_err(dev, "%s: invalid path=%ld\n", __func__, PTR_ERR(path)); + goto free_icc_data; + } + + if (src_data->tag && src_data->tag == dst_data->tag) + icc_set_tag(path, src_data->tag); + + path->name = kasprintf(GFP_KERNEL, "%s-%s", + src_data->node->name, dst_data->node->name); + if (!path->name) { + kfree(path); + path = ERR_PTR(-ENOMEM); + } + +free_icc_data: + kfree(src_data); + kfree(dst_data); + return path; +} +EXPORT_SYMBOL_GPL(of_icc_get_by_index); + +/** + * of_icc_get() - get a path handle from a DT node based on name + * @dev: device pointer for the consumer device + * @name: interconnect path 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. + * If the interconnect API is disabled, NULL is returned and the consumer + * drivers will still build. Drivers are free to handle this specifically, + * but they don't have to. + * + * Return: icc_path pointer on success or ERR_PTR() on error. NULL is returned + * when the API is disabled or the "interconnects" DT property is missing. + */ +struct icc_path *of_icc_get(struct device *dev, const char *name) +{ + struct device_node *np; + int idx = 0; + + if (!dev || !dev->of_node) + return ERR_PTR(-ENODEV); + + np = dev->of_node; + + /* + * When the consumer DT node do not have "interconnects" property + * return a NULL path to skip setting constraints. + */ + if (!of_find_property(np, "interconnects", NULL)) + return NULL; + + /* + * We use a combination of phandle and specifier for endpoint. For now + * lets support only global ids and extend this in the future if needed + * without breaking DT compatibility. + */ + if (name) { + idx = of_property_match_string(np, "interconnect-names", name); + if (idx < 0) + return ERR_PTR(idx); + } + + return of_icc_get_by_index(dev, idx); +} +EXPORT_SYMBOL_GPL(of_icc_get); + +/** + * icc_set_tag() - set an optional tag on a path + * @path: the path we want to tag + * @tag: the tag value + * + * This function allows consumers to append a tag to the requests associated + * with a path, so that a different aggregation could be done based on this tag. + */ +void icc_set_tag(struct icc_path *path, u32 tag) +{ + int i; + + if (!path) + return; + + mutex_lock(&icc_lock); + + for (i = 0; i < path->num_nodes; i++) + path->reqs[i].tag = tag; + + mutex_unlock(&icc_lock); +} +EXPORT_SYMBOL_GPL(icc_set_tag); + +/** + * icc_get_name() - Get name of the icc path + * @path: reference to the path returned by icc_get() + * + * This function is used by an interconnect consumer to get the name of the icc + * path. + * + * Returns a valid pointer on success, or NULL otherwise. + */ +const char *icc_get_name(struct icc_path *path) +{ + if (!path) + return NULL; + + return path->name; +} +EXPORT_SYMBOL_GPL(icc_get_name); + +/** + * icc_set_bw() - set bandwidth constraints on an interconnect path + * @path: reference to the path returned by icc_get() + * @avg_bw: average bandwidth in kilobytes per second + * @peak_bw: peak bandwidth in kilobytes per second + * + * This function is used by an interconnect consumer to express its own needs + * in terms of bandwidth for a previously requested path between two endpoints. + * The requests are aggregated and each node is updated accordingly. The entire + * path is locked by a mutex to ensure that the set() is completed. + * The @path can be NULL when the "interconnects" DT properties is missing, + * which will mean that no constraints will be set. + * + * Returns 0 on success, or an appropriate error code otherwise. + */ +int icc_set_bw(struct icc_path *path, u32 avg_bw, u32 peak_bw) +{ + struct icc_node *node; + u32 old_avg, old_peak; + size_t i; + int ret; + + if (!path) + return 0; + + if (WARN_ON(IS_ERR(path) || !path->num_nodes)) + return -EINVAL; + + mutex_lock(&icc_bw_lock); + + old_avg = path->reqs[0].avg_bw; + old_peak = path->reqs[0].peak_bw; + + for (i = 0; i < path->num_nodes; i++) { + node = path->reqs[i].node; + + /* update the consumer request for this path */ + path->reqs[i].avg_bw = avg_bw; + path->reqs[i].peak_bw = peak_bw; + + /* aggregate requests for this node */ + aggregate_requests(node); + + trace_icc_set_bw(path, node, i, avg_bw, peak_bw); + } + + ret = apply_constraints(path); + if (ret) { + pr_debug("interconnect: error applying constraints (%d)\n", + ret); + + for (i = 0; i < path->num_nodes; i++) { + node = path->reqs[i].node; + path->reqs[i].avg_bw = old_avg; + path->reqs[i].peak_bw = old_peak; + aggregate_requests(node); + } + apply_constraints(path); + } + + mutex_unlock(&icc_bw_lock); + + trace_icc_set_bw_end(path, ret); + + return ret; +} +EXPORT_SYMBOL_GPL(icc_set_bw); + +static int __icc_enable(struct icc_path *path, bool enable) +{ + int i; + + if (!path) + return 0; + + if (WARN_ON(IS_ERR(path) || !path->num_nodes)) + return -EINVAL; + + mutex_lock(&icc_lock); + + for (i = 0; i < path->num_nodes; i++) + path->reqs[i].enabled = enable; + + mutex_unlock(&icc_lock); + + return icc_set_bw(path, path->reqs[0].avg_bw, + path->reqs[0].peak_bw); +} + +int icc_enable(struct icc_path *path) +{ + return __icc_enable(path, true); +} +EXPORT_SYMBOL_GPL(icc_enable); + +int icc_disable(struct icc_path *path) +{ + return __icc_enable(path, false); +} +EXPORT_SYMBOL_GPL(icc_disable); + +/** + * icc_get() - return a handle for path between two endpoints + * @dev: the device requesting the path + * @src_id: source device port id + * @dst_id: destination device port id + * + * 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. + * If the interconnect API is disabled, NULL is returned and the consumer + * drivers will still build. Drivers are free to handle this specifically, + * but they don't have to. + * + * Return: icc_path pointer on success, ERR_PTR() on error or NULL if the + * interconnect API is disabled. + */ +struct icc_path *icc_get(struct device *dev, const int src_id, const int dst_id) +{ + struct icc_node *src, *dst; + struct icc_path *path = ERR_PTR(-EPROBE_DEFER); + + mutex_lock(&icc_lock); + + src = node_find(src_id); + if (!src) + goto out; + + dst = node_find(dst_id); + if (!dst) + goto out; + + path = path_find(dev, src, dst); + 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->name, dst->name); + if (!path->name) { + kfree(path); + path = ERR_PTR(-ENOMEM); + } +out: + mutex_unlock(&icc_lock); + return path; +} +EXPORT_SYMBOL_GPL(icc_get); + +/** + * icc_put() - release the reference to the icc_path + * @path: interconnect path + * + * Use this function to release the constraints on a path when the path is + * no longer needed. The constraints will be re-aggregated. + */ +void icc_put(struct icc_path *path) +{ + struct icc_node *node; + size_t i; + int ret; + + if (!path || WARN_ON(IS_ERR(path))) + return; + + ret = icc_set_bw(path, 0, 0); + if (ret) + pr_err("%s: error (%d)\n", __func__, ret); + + mutex_lock(&icc_lock); + for (i = 0; i < path->num_nodes; i++) { + node = path->reqs[i].node; + hlist_del(&path->reqs[i].req_node); + if (!WARN_ON(!node->provider->users)) + node->provider->users--; + } + mutex_unlock(&icc_lock); + + kfree_const(path->name); + kfree(path); +} +EXPORT_SYMBOL_GPL(icc_put); + +static struct icc_node *icc_node_create_nolock(int id) +{ + struct icc_node *node; + + /* check if node already exists */ + node = node_find(id); + if (node) + return node; + + node = kzalloc(sizeof(*node), GFP_KERNEL); + if (!node) + return ERR_PTR(-ENOMEM); + + id = idr_alloc(&icc_idr, node, id, id + 1, GFP_KERNEL); + if (id < 0) { + WARN(1, "%s: couldn't get idr\n", __func__); + kfree(node); + return ERR_PTR(id); + } + + node->id = id; + + return node; +} + +/** + * icc_node_create() - create a node + * @id: node id + * + * Return: icc_node pointer on success, or ERR_PTR() on error + */ +struct icc_node *icc_node_create(int id) +{ + struct icc_node *node; + + mutex_lock(&icc_lock); + + node = icc_node_create_nolock(id); + + mutex_unlock(&icc_lock); + + return node; +} +EXPORT_SYMBOL_GPL(icc_node_create); + +/** + * icc_node_destroy() - destroy a node + * @id: node id + */ +void icc_node_destroy(int id) +{ + struct icc_node *node; + + mutex_lock(&icc_lock); + + node = node_find(id); + if (node) { + idr_remove(&icc_idr, node->id); + WARN_ON(!hlist_empty(&node->req_list)); + } + + mutex_unlock(&icc_lock); + + if (!node) + return; + + kfree(node->links); + kfree(node); +} +EXPORT_SYMBOL_GPL(icc_node_destroy); + +/** + * icc_link_create() - create a link between two nodes + * @node: source node id + * @dst_id: destination node id + * + * Create a link between two nodes. The nodes might belong to different + * interconnect providers and the @dst_id node might not exist (if the + * provider driver has not probed yet). So just create the @dst_id node + * and when the actual provider driver is probed, the rest of the node + * data is filled. + * + * Return: 0 on success, or an error code otherwise + */ +int icc_link_create(struct icc_node *node, const int dst_id) +{ + struct icc_node *dst; + struct icc_node **new; + int ret = 0; + + if (!node->provider) + return -EINVAL; + + mutex_lock(&icc_lock); + + dst = node_find(dst_id); + if (!dst) { + dst = icc_node_create_nolock(dst_id); + + if (IS_ERR(dst)) { + ret = PTR_ERR(dst); + goto out; + } + } + + new = krealloc(node->links, + (node->num_links + 1) * sizeof(*node->links), + GFP_KERNEL); + if (!new) { + ret = -ENOMEM; + goto out; + } + + node->links = new; + node->links[node->num_links++] = dst; + +out: + mutex_unlock(&icc_lock); + + return ret; +} +EXPORT_SYMBOL_GPL(icc_link_create); + +/** + * icc_link_destroy() - destroy a link between two nodes + * @src: pointer to source node + * @dst: pointer to destination node + * + * Return: 0 on success, or an error code otherwise + */ +int icc_link_destroy(struct icc_node *src, struct icc_node *dst) +{ + struct icc_node **new; + size_t slot; + int ret = 0; + + if (IS_ERR_OR_NULL(src)) + return -EINVAL; + + if (IS_ERR_OR_NULL(dst)) + return -EINVAL; + + mutex_lock(&icc_lock); + + for (slot = 0; slot < src->num_links; slot++) + if (src->links[slot] == dst) + break; + + if (WARN_ON(slot == src->num_links)) { + ret = -ENXIO; + goto out; + } + + src->links[slot] = src->links[--src->num_links]; + + new = krealloc(src->links, src->num_links * sizeof(*src->links), + GFP_KERNEL); + if (new) + src->links = new; + else + ret = -ENOMEM; + +out: + mutex_unlock(&icc_lock); + + return ret; +} +EXPORT_SYMBOL_GPL(icc_link_destroy); + +/** + * icc_node_add() - add interconnect node to interconnect provider + * @node: pointer to the interconnect node + * @provider: pointer to the interconnect provider + */ +void icc_node_add(struct icc_node *node, struct icc_provider *provider) +{ + if (WARN_ON(node->provider)) + return; + + mutex_lock(&icc_lock); + mutex_lock(&icc_bw_lock); + + node->provider = provider; + list_add_tail(&node->node_list, &provider->nodes); + + /* get the initial bandwidth values and sync them with hardware */ + if (provider->get_bw) { + provider->get_bw(node, &node->init_avg, &node->init_peak); + } else { + node->init_avg = INT_MAX; + node->init_peak = INT_MAX; + } + node->avg_bw = node->init_avg; + node->peak_bw = node->init_peak; + + if (provider->pre_aggregate) + provider->pre_aggregate(node); + + if (provider->aggregate) + provider->aggregate(node, 0, node->init_avg, node->init_peak, + &node->avg_bw, &node->peak_bw); + + provider->set(node, node); + node->avg_bw = 0; + node->peak_bw = 0; + + mutex_unlock(&icc_bw_lock); + mutex_unlock(&icc_lock); +} +EXPORT_SYMBOL_GPL(icc_node_add); + +/** + * icc_node_del() - delete interconnect node from interconnect provider + * @node: pointer to the interconnect node + */ +void icc_node_del(struct icc_node *node) +{ + mutex_lock(&icc_lock); + + list_del(&node->node_list); + + mutex_unlock(&icc_lock); +} +EXPORT_SYMBOL_GPL(icc_node_del); + +/** + * icc_nodes_remove() - remove all previously added nodes from provider + * @provider: the interconnect provider we are removing nodes from + * + * Return: 0 on success, or an error code otherwise + */ +int icc_nodes_remove(struct icc_provider *provider) +{ + struct icc_node *n, *tmp; + + if (WARN_ON(IS_ERR_OR_NULL(provider))) + return -EINVAL; + + list_for_each_entry_safe_reverse(n, tmp, &provider->nodes, node_list) { + icc_node_del(n); + icc_node_destroy(n->id); + } + + return 0; +} +EXPORT_SYMBOL_GPL(icc_nodes_remove); + +/** + * icc_provider_init() - initialize a new interconnect provider + * @provider: the interconnect provider to initialize + * + * Must be called before adding nodes to the provider. + */ +void icc_provider_init(struct icc_provider *provider) +{ + WARN_ON(!provider->set); + + INIT_LIST_HEAD(&provider->nodes); +} +EXPORT_SYMBOL_GPL(icc_provider_init); + +/** + * icc_provider_register() - register a new interconnect provider + * @provider: the interconnect provider to register + * + * Return: 0 on success, or an error code otherwise + */ +int icc_provider_register(struct icc_provider *provider) +{ + if (WARN_ON(!provider->xlate && !provider->xlate_extended)) + return -EINVAL; + + mutex_lock(&icc_lock); + list_add_tail(&provider->provider_list, &icc_providers); + mutex_unlock(&icc_lock); + + dev_dbg(provider->dev, "interconnect provider registered\n"); + + return 0; +} +EXPORT_SYMBOL_GPL(icc_provider_register); + +/** + * icc_provider_deregister() - deregister an interconnect provider + * @provider: the interconnect provider to deregister + */ +void icc_provider_deregister(struct icc_provider *provider) +{ + mutex_lock(&icc_lock); + WARN_ON(provider->users); + + list_del(&provider->provider_list); + mutex_unlock(&icc_lock); +} +EXPORT_SYMBOL_GPL(icc_provider_deregister); + +int icc_provider_add(struct icc_provider *provider) +{ + icc_provider_init(provider); + + return icc_provider_register(provider); +} +EXPORT_SYMBOL_GPL(icc_provider_add); + +void icc_provider_del(struct icc_provider *provider) +{ + WARN_ON(!list_empty(&provider->nodes)); + + icc_provider_deregister(provider); +} +EXPORT_SYMBOL_GPL(icc_provider_del); + +static const struct of_device_id __maybe_unused ignore_list[] = { + { .compatible = "qcom,sc7180-ipa-virt" }, + { .compatible = "qcom,sdx55-ipa-virt" }, + { .compatible = "qcom,sm8150-ipa-virt" }, + {} +}; + +static int of_count_icc_providers(struct device_node *np) +{ + struct device_node *child; + int count = 0; + + for_each_available_child_of_node(np, child) { + if (of_property_read_bool(child, "#interconnect-cells") && + likely(!of_match_node(ignore_list, child))) + count++; + count += of_count_icc_providers(child); + } + + return count; +} + +void icc_sync_state(struct device *dev) +{ + struct icc_provider *p; + struct icc_node *n; + static int count; + + count++; + + if (count < providers_count) + 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"); + list_for_each_entry(n, &p->nodes, node_list) { + if (n->init_avg || n->init_peak) { + n->init_avg = 0; + n->init_peak = 0; + aggregate_requests(n); + p->set(n, n); + } + } + } + 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; + + /* 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); + + icc_debugfs_dir = debugfs_create_dir("interconnect", NULL); + debugfs_create_file("interconnect_summary", 0444, + icc_debugfs_dir, NULL, &icc_summary_fops); + debugfs_create_file("interconnect_graph", 0444, + icc_debugfs_dir, NULL, &icc_graph_fops); + return 0; +} + +device_initcall(icc_init); + +MODULE_AUTHOR("Georgi Djakov <georgi.djakov@linaro.org>"); +MODULE_DESCRIPTION("Interconnect Driver Core"); +MODULE_LICENSE("GPL v2"); |