projects/linux·blob v5.8 · refs

249 lines · 6.3 KiB

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