1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Generic OPP debugfs interface
4 *
5 * Copyright (C) 2015-2016 Viresh Kumar <viresh.kumar@linaro.org>
6 */
7
8#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9
10#include <linux/debugfs.h>
11#include <linux/device.h>
12#include <linux/err.h>
13#include <linux/of.h>
14#include <linux/init.h>
15#include <linux/limits.h>
16#include <linux/slab.h>
17
18#include "opp.h"
19
20static struct dentry *rootdir;
21
22static void opp_set_dev_name(const struct device *dev, char *name)
23{
24	if (dev->parent)
25		snprintf(name, NAME_MAX, "%s-%s", dev_name(dev->parent),
26			 dev_name(dev));
27	else
28		snprintf(name, NAME_MAX, "%s", dev_name(dev));
29}
30
31void opp_debug_remove_one(struct dev_pm_opp *opp)
32{
33	debugfs_remove_recursive(opp->dentry);
34}
35
36static ssize_t bw_name_read(struct file *fp, char __user *userbuf,
37			    size_t count, loff_t *ppos)
38{
39	struct icc_path *path = fp->private_data;
40	const char *name = icc_get_name(path);
41	char buf[64];
42	int i = 0;
43
44	if (name)
45		i = scnprintf(buf, sizeof(buf), "%.62s\n", name);
46
47	return simple_read_from_buffer(userbuf, count, ppos, buf, i);
48}
49
50static const struct file_operations bw_name_fops = {
51	.open = simple_open,
52	.read = bw_name_read,
53	.llseek = default_llseek,
54};
55
56static void opp_debug_create_bw(struct dev_pm_opp *opp,
57				struct opp_table *opp_table,
58				struct dentry *pdentry)
59{
60	struct dentry *d;
61	char name[] = "icc-path-XXXXXXXXXXX"; /* Integers can take 11 chars max */
62	int i;
63
64	for (i = 0; i < opp_table->path_count; i++) {
65		snprintf(name, sizeof(name), "icc-path-%d", i);
66
67		/* Create per-path directory */
68		d = debugfs_create_dir(name, pdentry);
69
70		debugfs_create_file("name", S_IRUGO, d, opp_table->paths[i],
71				    &bw_name_fops);
72		debugfs_create_u32("peak_bw", S_IRUGO, d,
73				   &opp->bandwidth[i].peak);
74		debugfs_create_u32("avg_bw", S_IRUGO, d,
75				   &opp->bandwidth[i].avg);
76	}
77}
78
79static void opp_debug_create_clks(struct dev_pm_opp *opp,
80				  struct opp_table *opp_table,
81				  struct dentry *pdentry)
82{
83	char name[] = "rate_hz_XXXXXXXXXXX"; /* Integers can take 11 chars max */
84	int i;
85
86	if (opp_table->clk_count == 1) {
87		debugfs_create_ulong("rate_hz", S_IRUGO, pdentry, &opp->rates[0]);
88		return;
89	}
90
91	for (i = 0; i < opp_table->clk_count; i++) {
92		snprintf(name, sizeof(name), "rate_hz_%d", i);
93		debugfs_create_ulong(name, S_IRUGO, pdentry, &opp->rates[i]);
94	}
95}
96
97static void opp_debug_create_supplies(struct dev_pm_opp *opp,
98				      struct opp_table *opp_table,
99				      struct dentry *pdentry)
100{
101	struct dentry *d;
102	int i;
103
104	for (i = 0; i < opp_table->regulator_count; i++) {
105		char name[] = "supply-XXXXXXXXXXX"; /* Integers can take 11 chars max */
106
107		snprintf(name, sizeof(name), "supply-%d", i);
108
109		/* Create per-opp directory */
110		d = debugfs_create_dir(name, pdentry);
111
112		debugfs_create_ulong("u_volt_target", S_IRUGO, d,
113				     &opp->supplies[i].u_volt);
114
115		debugfs_create_ulong("u_volt_min", S_IRUGO, d,
116				     &opp->supplies[i].u_volt_min);
117
118		debugfs_create_ulong("u_volt_max", S_IRUGO, d,
119				     &opp->supplies[i].u_volt_max);
120
121		debugfs_create_ulong("u_amp", S_IRUGO, d,
122				     &opp->supplies[i].u_amp);
123
124		debugfs_create_ulong("u_watt", S_IRUGO, d,
125				     &opp->supplies[i].u_watt);
126	}
127}
128
129void opp_debug_create_one(struct dev_pm_opp *opp, struct opp_table *opp_table)
130{
131	struct dentry *pdentry = opp_table->dentry;
132	struct dentry *d;
133	unsigned long id;
134	char name[25];	/* 20 chars for 64 bit value + 5 (opp:\0) */
135
136	/*
137	 * Get directory name for OPP.
138	 *
139	 * - Normally rate is unique to each OPP, use it to get unique opp-name.
140	 * - For some devices rate isn't available or there are multiple, use
141	 *   index instead for them.
142	 */
143	if (likely(opp_table->clk_count == 1 && opp->rates[0]))
144		id = opp->rates[0];
145	else
146		id = _get_opp_count(opp_table);
147
148	snprintf(name, sizeof(name), "opp:%lu", id);
149
150	/* Create per-opp directory */
151	d = debugfs_create_dir(name, pdentry);
152
153	debugfs_create_bool("available", S_IRUGO, d, &opp->available);
154	debugfs_create_bool("dynamic", S_IRUGO, d, &opp->dynamic);
155	debugfs_create_bool("turbo", S_IRUGO, d, &opp->turbo);
156	debugfs_create_bool("suspend", S_IRUGO, d, &opp->suspend);
157	debugfs_create_u32("level", S_IRUGO, d, &opp->level);
158	debugfs_create_ulong("clock_latency_ns", S_IRUGO, d,
159			     &opp->clock_latency_ns);
160
161	opp->of_name = of_node_full_name(opp->np);
162	debugfs_create_str("of_name", S_IRUGO, d, (char **)&opp->of_name);
163
164	opp_debug_create_clks(opp, opp_table, d);
165	opp_debug_create_supplies(opp, opp_table, d);
166	opp_debug_create_bw(opp, opp_table, d);
167
168	opp->dentry = d;
169}
170
171static void opp_list_debug_create_dir(struct opp_device *opp_dev,
172				      struct opp_table *opp_table)
173{
174	const struct device *dev = opp_dev->dev;
175	struct dentry *d;
176
177	opp_set_dev_name(dev, opp_table->dentry_name);
178
179	/* Create device specific directory */
180	d = debugfs_create_dir(opp_table->dentry_name, rootdir);
181
182	opp_dev->dentry = d;
183	opp_table->dentry = d;
184}
185
186static void opp_list_debug_create_link(struct opp_device *opp_dev,
187				       struct opp_table *opp_table)
188{
189	char name[NAME_MAX];
190
191	opp_set_dev_name(opp_dev->dev, name);
192
193	/* Create device specific directory link */
194	opp_dev->dentry = debugfs_create_symlink(name, rootdir,
195						 opp_table->dentry_name);
196}
197
198/**
199 * opp_debug_register - add a device opp node to the debugfs 'opp' directory
200 * @opp_dev: opp-dev pointer for device
201 * @opp_table: the device-opp being added
202 *
203 * Dynamically adds device specific directory in debugfs 'opp' directory. If the
204 * device-opp is shared with other devices, then links will be created for all
205 * devices except the first.
206 */
207void opp_debug_register(struct opp_device *opp_dev, struct opp_table *opp_table)
208{
209	if (opp_table->dentry)
210		opp_list_debug_create_link(opp_dev, opp_table);
211	else
212		opp_list_debug_create_dir(opp_dev, opp_table);
213}
214
215static void opp_migrate_dentry(struct opp_device *opp_dev,
216			       struct opp_table *opp_table)
217{
218	struct opp_device *new_dev = NULL, *iter;
219	const struct device *dev;
220	struct dentry *dentry;
221
222	/* Look for next opp-dev */
223	list_for_each_entry(iter, &opp_table->dev_list, node)
224		if (iter != opp_dev) {
225			new_dev = iter;
226			break;
227		}
228
229	BUG_ON(!new_dev);
230
231	/* new_dev is guaranteed to be valid here */
232	dev = new_dev->dev;
233	debugfs_remove_recursive(new_dev->dentry);
234
235	opp_set_dev_name(dev, opp_table->dentry_name);
236
237	dentry = debugfs_rename(rootdir, opp_dev->dentry, rootdir,
238				opp_table->dentry_name);
239	if (IS_ERR(dentry)) {
240		dev_err(dev, "%s: Failed to rename link from: %s to %s\n",
241			__func__, dev_name(opp_dev->dev), dev_name(dev));
242		return;
243	}
244
245	new_dev->dentry = dentry;
246	opp_table->dentry = dentry;
247}
248
249/**
250 * opp_debug_unregister - remove a device opp node from debugfs opp directory
251 * @opp_dev: opp-dev pointer for device
252 * @opp_table: the device-opp being removed
253 *
254 * Dynamically removes device specific directory from debugfs 'opp' directory.
255 */
256void opp_debug_unregister(struct opp_device *opp_dev,
257			  struct opp_table *opp_table)
258{
259	if (opp_dev->dentry == opp_table->dentry) {
260		/* Move the real dentry object under another device */
261		if (!list_is_singular(&opp_table->dev_list)) {
262			opp_migrate_dentry(opp_dev, opp_table);
263			goto out;
264		}
265		opp_table->dentry = NULL;
266	}
267
268	debugfs_remove_recursive(opp_dev->dentry);
269
270out:
271	opp_dev->dentry = NULL;
272}
273
274static int __init opp_debug_init(void)
275{
276	/* Create /sys/kernel/debug/opp directory */
277	rootdir = debugfs_create_dir("opp", NULL);
278
279	return 0;
280}
281core_initcall(opp_debug_init);
282