From 0675c10316a29db4ef61bb3006d64183df90b33f Mon Sep 17 00:00:00 2001 From: Murali Krishna Date: Tue, 9 Jun 2026 16:09:57 +0530 Subject: [PATCH] interconnect: qcom: Add bandwidth limiter support for QLI targets Introduce a sysfs interface to allow userspace-controlled bandwidth limiting for QLI targets. The current PMU-based scaling using static DDR-CPU operating points is overly aggressive for certain workloads and results in power regressions. Provide a fine-grained mechanism to restrict bandwidth at the client level, enabling better control of interconnect usage. This improves power efficiency by allowing targeted bandwidth throttling for specific clients and workloads. List of all the interconnect clients are populated inside /sys/kernel/interconnect folder and each client's voting can be limited by setting the limit_ab, limit_ib and limit_commit sysfs options present inside the path folder. Following would be the directory structure. + soc:qcom,dcvs:llcc:sp + chm_apps-qns_llcc --> path used by the client - limit_ab --> AB limit in KBps - limit_ib --> IB limit in KBps - limit_commit --> limits will be applied once commit is set Signed-off-by: Raviteja Laggyshetty --- drivers/interconnect/core.c | 313 +++++++- drivers/interconnect/core.c.orig | 1252 ++++++++++++++++++++++++++++++ drivers/interconnect/internal.h | 41 + 3 files changed, 1604 insertions(+), 2 deletions(-) create mode 100644 drivers/interconnect/core.c.orig diff --git a/drivers/interconnect/core.c b/drivers/interconnect/core.c index 6cc979b26151e..6cc59f5e6ff19 100644 --- a/drivers/interconnect/core.c +++ b/drivers/interconnect/core.c @@ -12,9 +12,11 @@ #include #include #include +#include #include #include #include +#include #include #include @@ -27,11 +29,14 @@ static DEFINE_IDR(icc_idr); static LIST_HEAD(icc_providers); +static LIST_HEAD(icc_clients); static int providers_count; static bool synced_state; static DEFINE_MUTEX(icc_lock); static DEFINE_MUTEX(icc_bw_lock); +static DEFINE_MUTEX(icc_sysfs_lock); static struct dentry *icc_debugfs_dir; +static struct kobject *icc_kobj; static void icc_summary_show_one(struct seq_file *s, struct icc_node *n) { @@ -284,10 +289,18 @@ static int aggregate_requests(struct icc_node *node) if (r->enabled) { avg_bw = r->avg_bw; peak_bw = r->peak_bw; + + if (r->limit_ab) + avg_bw = min(avg_bw, r->limit_ab); + + if (r->limit_ib) + peak_bw = min(peak_bw, r->limit_ib); + } else { avg_bw = 0; peak_bw = 0; } + p->aggregate(node, r->tag, avg_bw, peak_bw, &node->avg_bw, &node->peak_bw); @@ -443,6 +456,225 @@ struct icc_path *devm_of_icc_get(struct device *dev, const char *name) } EXPORT_SYMBOL_GPL(devm_of_icc_get); +static int icc_limit_apply(struct icc_client_path *l_path, + u32 limit_ab, u32 limit_ib) +{ + struct icc_path *path = l_path->path; + struct icc_node *node; + int i,ret; + + if (!path) + return -EINVAL; + + mutex_lock(&icc_lock); + mutex_lock(&icc_bw_lock); + for (i = 0; i < path->num_nodes; i++) { + node = path->reqs[i].node; + path->reqs[i].limit_ab = limit_ab; + path->reqs[i].limit_ib = limit_ib; + aggregate_requests(node); + } + + ret = apply_constraints(path); + mutex_unlock(&icc_bw_lock); + mutex_unlock(&icc_lock); + + return ret; +} + +static ssize_t limit_ab_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + u32 val; + struct icc_client_path *l_path = container_of(kobj, struct icc_client_path, kobj); + + mutex_lock(&icc_sysfs_lock); + val = l_path->limit_ab; + mutex_unlock(&icc_sysfs_lock); + + return sysfs_emit(buf, "%u\n", val); +} + +static ssize_t limit_ab_store(struct kobject *kobj, + struct kobj_attribute *attr, const char *buf, size_t count) +{ + u32 val; + int ret = 0; + struct icc_client_path *l_path = container_of(kobj, struct icc_client_path, kobj); + + if (kstrtou32(buf, 0, &val)) + return -EINVAL; + + mutex_lock(&icc_sysfs_lock); + l_path->limit_ab = val; + mutex_unlock(&icc_sysfs_lock); + if (ret) + return ret; + + return count; +} + +static ssize_t limit_ib_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + u32 val; + struct icc_client_path *l_path = container_of(kobj, struct icc_client_path, kobj); + + mutex_lock(&icc_sysfs_lock); + val = l_path->limit_ib; + mutex_unlock(&icc_sysfs_lock); + + return sysfs_emit(buf, "%u\n", val); +} + +static ssize_t limit_ib_store(struct kobject *kobj, + struct kobj_attribute *attr, const char *buf, size_t count) +{ + u32 val; + int ret = 0; + struct icc_client_path *l_path = container_of(kobj, struct icc_client_path, kobj); + + if (kstrtou32(buf, 0, &val)) + return -EINVAL; + + mutex_lock(&icc_sysfs_lock); + + l_path->limit_ib = val; + + mutex_unlock(&icc_sysfs_lock); + if (ret) + return ret; + + return count; +} + +static ssize_t limit_commit_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + bool val; + struct icc_client_path *l_path = container_of(kobj, struct icc_client_path, kobj); + + mutex_lock(&icc_sysfs_lock); + val = l_path->commit; + mutex_unlock(&icc_sysfs_lock); + + return sysfs_emit(buf, "%d\n", val); +} + +static ssize_t limit_commit_store(struct kobject *kobj, + struct kobj_attribute *attr, const char *buf, size_t count) +{ + bool val; + u32 prev_ab , prev_ib ; + int ret = 0; + struct icc_client_path *l_path = container_of(kobj, struct icc_client_path, kobj); + + if (kstrtobool(buf, &val)) + return -EINVAL; + + + mutex_lock(&icc_sysfs_lock); + if (!l_path->path) { + ret = -EINVAL; + goto unlock; + } + + prev_ab = l_path->limit_ab; + prev_ib = l_path->limit_ib; + + if (l_path->commit != val) { + if (val) + ret = icc_limit_apply(l_path, l_path->limit_ab, + l_path->limit_ib); + else + ret = icc_limit_apply(l_path, 0, 0); + if (ret) { + icc_limit_apply(l_path, prev_ab, + prev_ib); + goto unlock; + } + } + + l_path->commit = val; + +unlock: + mutex_unlock(&icc_sysfs_lock); + if (ret) + return ret; + + return count; +} +static void icc_limit_release(struct kobject *kobj) +{ +} + +static void icc_client_release(struct kobject *kobj) +{ + struct icc_client *client = container_of(kobj, struct icc_client, kobj); + + kfree(client); +} + +static const struct kobj_type icc_client_ktype = { + .release = icc_client_release, + .sysfs_ops = &kobj_sysfs_ops, +}; + +static const struct kobj_type icc_limit_ktype = { + .release = icc_limit_release, + .sysfs_ops = &kobj_sysfs_ops, +}; + +static struct kobj_attribute attr_limit_ab = __ATTR_RW(limit_ab); +static struct kobj_attribute attr_limit_ib = __ATTR_RW(limit_ib); +static struct kobj_attribute attr_limit_commit = __ATTR_RW(limit_commit); + +static struct attribute *bw_limiter_attr[] = { + &attr_limit_ab.attr, + &attr_limit_ib.attr, + &attr_limit_commit.attr, + NULL, +}; + +static struct attribute_group icc_bw_limit_attrs = { + .attrs = bw_limiter_attr, +}; + + +static void icc_sysfs_create_path_entry(struct device *dev, struct icc_client *c) +{ + int i, ret; + + if (!c->kobj_inited) { + ret = kobject_init_and_add(&c->kobj, &icc_client_ktype, + icc_kobj, dev_name(c->dev)); + if (ret) + kobject_put(&c->kobj); + else + c->kobj_inited = true; + } + + for (i = 0; i < c->num_paths; i++) { + if (!c->paths[i].path || c->paths[i].kobj_inited) + continue; + + ret = kobject_init_and_add(&c->paths[i].kobj, &icc_limit_ktype, + &c->kobj, c->paths[i].path->name); + if (ret) { + kobject_put(&c->paths[i].kobj); + continue; + } + + ret = sysfs_create_group(&c->paths[i].kobj, &icc_bw_limit_attrs); + if (ret) { + kobject_put(&c->paths[i].kobj); + continue; + } + + c->paths[i].kobj_inited = true; + } +} + /** * of_icc_get_by_index() - get a path handle from a DT node based on index * @dev: device pointer for the consumer device @@ -464,7 +696,8 @@ struct icc_path *of_icc_get_by_index(struct device *dev, int idx) struct icc_node_data *src_data, *dst_data; struct device_node *np; struct of_phandle_args src_args, dst_args; - int ret; + struct icc_client *c, *client = NULL; + int ret, num_paths; if (!dev || !dev->of_node) return ERR_PTR(-ENODEV); @@ -478,6 +711,9 @@ struct icc_path *of_icc_get_by_index(struct device *dev, int idx) if (!of_property_present(np, "interconnects")) return NULL; + num_paths = max(of_count_phandle_with_args(np, "interconnects", + "#interconnect-cells")/2, 1); + /* * 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 @@ -507,7 +743,6 @@ struct icc_path *of_icc_get_by_index(struct device *dev, int idx) } 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); @@ -530,6 +765,33 @@ struct icc_path *of_icc_get_by_index(struct device *dev, int idx) if (!path->name) { kfree(path); path = ERR_PTR(-ENOMEM); + } else { + mutex_lock(&icc_sysfs_lock); + list_for_each_entry(c, &icc_clients, client_list) { + if (c->dev == dev) { + client = c; + break; + } + } + + if (!client) { + client = kzalloc(struct_size(client, paths, num_paths), + GFP_KERNEL); + if (client) { + client->dev = dev; + list_add_tail(&client->client_list, &icc_clients); + } + else { + mutex_unlock(&icc_sysfs_lock); + goto free_icc_data; + } + } + + if (client->num_paths < num_paths) + client->paths[client->num_paths++].path = path; + + icc_sysfs_create_path_entry(dev, client); + mutex_unlock(&icc_sysfs_lock); } free_icc_data: @@ -765,6 +1027,46 @@ static int __icc_enable(struct icc_path *path, bool enable) path->reqs[0].peak_bw); } +static void icc_client_remove_path(struct icc_path *path) +{ + struct icc_client *client; + size_t i; + + if (!path) + return; + + mutex_lock(&icc_sysfs_lock); + list_for_each_entry(client, &icc_clients, client_list) { + for (i = 0; i < client->num_paths; i++) { + if (client->paths[i].path != path) + continue; + + client->paths[i].path = NULL; + client->paths[i].limit_ab = 0; + client->paths[i].limit_ib = 0; + client->paths[i].commit = false; + if (client->paths[i].kobj_inited) { + client->paths[i].kobj_inited = false; + kobject_put(&client->paths[i].kobj); + } + + if (client->num_paths) + client->num_paths--; + + if (!client->num_paths) { + list_del(&client->client_list); + if (client->kobj_inited) + kobject_put(&client->kobj); + else + kfree(client); + } + mutex_unlock(&icc_sysfs_lock); + return; + } + } + mutex_unlock(&icc_sysfs_lock); +} + int icc_enable(struct icc_path *path) { return __icc_enable(path, true); @@ -807,6 +1109,8 @@ void icc_put(struct icc_path *path) node->provider->users--; } + icc_client_remove_path(path); + mutex_unlock(&icc_bw_lock); mutex_unlock(&icc_lock); @@ -1246,6 +1550,11 @@ static int __init icc_init(void) icc_debugfs_client_init(icc_debugfs_dir); + icc_kobj = kobject_create_and_add("interconnect", kernel_kobj); + if (!icc_kobj) { + pr_err("interconnect: failed to create sysfs kobject\n"); + } + return 0; } diff --git a/drivers/interconnect/core.c.orig b/drivers/interconnect/core.c.orig new file mode 100644 index 0000000000000..6cc979b26151e --- /dev/null +++ b/drivers/interconnect/core.c.orig @@ -0,0 +1,1252 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Interconnect framework core driver + * + * Copyright (c) 2017-2019, Linaro Ltd. + * Author: Georgi Djakov + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "internal.h" + +#define ICC_DYN_ID_START 100000 + +#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_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) +{ + 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; + + mutex_lock(&icc_bw_lock); + + 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; + } + + mutex_unlock(&icc_bw_lock); + + 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(const 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(const 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 (device_match_of_node(provider->dev, 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_property_present(np, "interconnects")) + 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_property_present(np, "interconnects")) + 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_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 + * + * 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: interconnect path + * + * 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: interconnect path + * @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_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); + mutex_lock(&icc_bw_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_bw_lock); + mutex_unlock(&icc_lock); + + kfree(path->name); + kfree(path); +} +EXPORT_SYMBOL_GPL(icc_put); + +static struct icc_node *icc_node_create_nolock(int id) +{ + struct icc_node *node; + + if (id >= ICC_DYN_ID_START) + return ERR_PTR(-EINVAL); + + /* 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); + + /* dynamic id allocation */ + if (id == ICC_ALLOC_DYN_ID) + id = idr_alloc(&icc_idr, node, ICC_DYN_ID_START, 0, GFP_KERNEL); + else + 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_dyn() - create a node with dynamic id + * + * Return: icc_node pointer on success, or ERR_PTR() on error + */ +struct icc_node *icc_node_create_dyn(void) +{ + struct icc_node *node; + + mutex_lock(&icc_lock); + + node = icc_node_create_nolock(ICC_ALLOC_DYN_ID); + + mutex_unlock(&icc_lock); + + return node; +} +EXPORT_SYMBOL_GPL(icc_node_create_dyn); + +/** + * 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); + if (node->id >= ICC_DYN_ID_START) + kfree(node->name); + kfree(node); +} +EXPORT_SYMBOL_GPL(icc_node_destroy); + +/** + * icc_node_set_name() - set node name + * @node: node + * @provider: node provider + * @name: node name + * + * Return: 0 on success, or -ENOMEM on allocation failure + */ +int icc_node_set_name(struct icc_node *node, const struct icc_provider *provider, const char *name) +{ + if (node->id >= ICC_DYN_ID_START) { + node->name = kasprintf(GFP_KERNEL, "%s@%s", name, + dev_name(provider->dev)); + if (!node->name) + return -ENOMEM; + } else { + node->name = name; + } + + return 0; +} +EXPORT_SYMBOL_GPL(icc_node_set_name); + +/** + * icc_link_nodes() - create link between two nodes + * @src_node: source node + * @dst_node: destination node + * + * Create a link between two nodes. The nodes might belong to different + * interconnect providers and the @dst_node might not exist (if the + * provider driver has not probed yet). So just create the @dst_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_nodes(struct icc_node *src_node, struct icc_node **dst_node) +{ + struct icc_node **new; + int ret = 0; + + if (!src_node->provider) + return -EINVAL; + + mutex_lock(&icc_lock); + + if (!*dst_node) { + *dst_node = icc_node_create_nolock(ICC_ALLOC_DYN_ID); + + if (IS_ERR(*dst_node)) { + ret = PTR_ERR(*dst_node); + goto out; + } + } + + new = krealloc(src_node->links, + (src_node->num_links + 1) * sizeof(*src_node->links), + GFP_KERNEL); + if (!new) { + ret = -ENOMEM; + goto out; + } + + src_node->links = new; + src_node->links[src_node->num_links++] = *dst_node; + +out: + mutex_unlock(&icc_lock); + + return ret; +} +EXPORT_SYMBOL_GPL(icc_link_nodes); + +/** + * 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_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 (node->avg_bw || node->peak_bw) { + 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); + if (provider->set) + 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); + +static const struct of_device_id __maybe_unused ignore_list[] = { + { .compatible = "qcom,sc7180-ipa-virt" }, + { .compatible = "qcom,sc8180x-ipa-virt" }, + { .compatible = "qcom,sdx55-ipa-virt" }, + { .compatible = "qcom,sm8150-ipa-virt" }, + { .compatible = "qcom,sm8250-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_present(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); + + icc_debugfs_client_init(icc_debugfs_dir); + + return 0; +} + +device_initcall(icc_init); diff --git a/drivers/interconnect/internal.h b/drivers/interconnect/internal.h index 3b9d50589c01a..af086a67b9f6a 100644 --- a/drivers/interconnect/internal.h +++ b/drivers/interconnect/internal.h @@ -9,6 +9,43 @@ #ifndef __DRIVERS_INTERCONNECT_INTERNAL_H #define __DRIVERS_INTERCONNECT_INTERNAL_H +/** + * struct icc_client_path - structure to hold client path information + * @kobj: kobj used for uniquely storing/showing the limit parameters + * associated with path + * @dev: client's dev node pointer + * @limit_ab: ab bw value in KBpS used for limiting client voting + * @limit_ib: ib bw value in KBpS used for limiting client voting + * @commit: used to enforce the limit on client voting on path + * @kobj_inited: bool to indicate if kobj init + */ +struct icc_client_path { + struct icc_path *path; + struct kobject kobj; + u32 limit_ab; + u32 limit_ib; + bool commit; + bool kobj_inited; +}; + +/** + * struct icc_client - structure to hold client path and limit information + * @client_list: list to hold the clients + * @kobj: kobj used for displaying the client list in sysfs + * @dev: client's dev node pointer + * @num_paths : number of paths used by client + * @kobj_inited: bool to indicate if kobj init + * @paths: paths used by the client + */ +struct icc_client { + struct list_head client_list; + struct kobject kobj; + struct device *dev; + size_t num_paths; + bool kobj_inited; + struct icc_client_path paths[] __counted_by(num_paths); +}; + /** * struct icc_req - constraints that are attached to each node * @req_node: entry in list of requests for the particular @node @@ -18,6 +55,8 @@ * @tag: path tag (optional) * @avg_bw: an integer describing the average bandwidth in kBps * @peak_bw: an integer describing the peak bandwidth in kBps + * @limit_ab: ab bw value in KBpS used for limiting client voting + * @limit_ib: ib bw value in KBpS used for limiting client voting */ struct icc_req { struct hlist_node req_node; @@ -27,6 +66,8 @@ struct icc_req { u32 tag; u32 avg_bw; u32 peak_bw; + u32 limit_ab; + u32 limit_ib; }; /**