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