path: root/drivers/interconnect/core.c

// 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 DEFINE_MUTEX(icc_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) {
				if (!r->dev)
					continue;

				seq_printf(s, "  %-27s %12u %12u %12u\n",
					   dev_name(r->dev), r->tag, r->avg_bw,
					   r->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 (!