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-rw-r--r--drivers/interconnect/core.c1184
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");