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/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), dev_name(dev));
25    } else {
26        snprintf(name, NAME_MAX, "%s", dev_name(dev));
27    }
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, size_t count, loff_t *ppos)
36{
37    struct icc_path *path = fp->private_data;
38    char buf[64];
39    int i;
40
41    i = scnprintf(buf, sizeof(buf), "%.62s\n", icc_get_name(path));
42
43    return simple_read_from_buffer(userbuf, count, ppos, buf, i);
44}
45
46static const struct file_operations bw_name_fops = {
47    .open = simple_open,
48    .read = bw_name_read,
49    .llseek = default_llseek,
50};
51
52static void opp_debug_create_bw(struct dev_pm_opp *opp, struct opp_table *opp_table, struct dentry *pdentry)
53{
54    struct dentry *d;
55    char name[11];
56    int i, ret;
57
58    for (i = 0; i < opp_table->path_count; i++) {
59        ret = snprintf(name, sizeof(name), "icc-path-%.1d", i);
60
61        /* Create per-path directory */
62        d = debugfs_create_dir(name, pdentry);
63
64        debugfs_create_file("name", S_IRUGO, d, opp_table->paths[i], &bw_name_fops);
65        debugfs_create_u32("peak_bw", S_IRUGO, d, &opp->bandwidth[i].peak);
66        debugfs_create_u32("avg_bw", S_IRUGO, d, &opp->bandwidth[i].avg);
67    }
68}
69
70static void opp_debug_create_supplies(struct dev_pm_opp *opp, struct opp_table *opp_table, struct dentry *pdentry)
71{
72    struct dentry *d;
73    int i, ret;
74
75    for (i = 0; i < opp_table->regulator_count; i++) {
76        char name[15];
77
78        ret = snprintf(name, sizeof(name), "supply-%d", i);
79
80        /* Create per-opp directory */
81        d = debugfs_create_dir(name, pdentry);
82
83        debugfs_create_ulong("u_volt_target", S_IRUGO, d, &opp->supplies[i].u_volt);
84
85        debugfs_create_ulong("u_volt_min", S_IRUGO, d, &opp->supplies[i].u_volt_min);
86
87        debugfs_create_ulong("u_volt_max", S_IRUGO, d, &opp->supplies[i].u_volt_max);
88
89        debugfs_create_ulong("u_amp", S_IRUGO, d, &opp->supplies[i].u_amp);
90    }
91}
92
93void opp_debug_create_one(struct dev_pm_opp *opp, struct opp_table *opp_table)
94{
95    struct dentry *pdentry = opp_table->dentry;
96    struct dentry *d;
97    unsigned long id;
98    char name[25]; /* 20 chars for 64 bit value + 5 (opp:\0) */
99    int ret;
100    /*
101     * Get directory name for OPP.
102     *
103     * - Normally rate is unique to each OPP, use it to get unique opp-name.
104     * - For some devices rate isn't available, use index instead.
105     */
106    if (likely(opp->rate)) {
107        id = opp->rate;
108    } else {
109        id = _get_opp_count(opp_table);
110    }
111
112    ret = snprintf(name, sizeof(name), "opp:%lu", id);
113
114    /* Create per-opp directory */
115    d = debugfs_create_dir(name, pdentry);
116
117    debugfs_create_bool("available", S_IRUGO, d, &opp->available);
118    debugfs_create_bool("dynamic", S_IRUGO, d, &opp->dynamic);
119    debugfs_create_bool("turbo", S_IRUGO, d, &opp->turbo);
120    debugfs_create_bool("suspend", S_IRUGO, d, &opp->suspend);
121    debugfs_create_u32("performance_state", S_IRUGO, d, &opp->pstate);
122    debugfs_create_ulong("rate_hz", S_IRUGO, d, &opp->rate);
123    debugfs_create_ulong("clock_latency_ns", S_IRUGO, d, &opp->clock_latency_ns);
124
125    opp_debug_create_supplies(opp, opp_table, d);
126    opp_debug_create_bw(opp, opp_table, d);
127
128    opp->dentry = d;
129}
130
131static void opp_list_debug_create_dir(struct opp_device *opp_dev, struct opp_table *opp_table)
132{
133    const struct device *dev = opp_dev->dev;
134    struct dentry *d;
135
136    opp_set_dev_name(dev, opp_table->dentry_name);
137
138    /* Create device specific directory */
139    d = debugfs_create_dir(opp_table->dentry_name, rootdir);
140
141    opp_dev->dentry = d;
142    opp_table->dentry = d;
143}
144
145static void opp_list_debug_create_link(struct opp_device *opp_dev, struct opp_table *opp_table)
146{
147    char name[NAME_MAX];
148
149    opp_set_dev_name(opp_dev->dev, name);
150
151    /* Create device specific directory link */
152    opp_dev->dentry = debugfs_create_symlink(name, rootdir, opp_table->dentry_name);
153}
154
155/**
156 * opp_debug_register - add a device opp node to the debugfs 'opp' directory
157 * @opp_dev: opp-dev pointer for device
158 * @opp_table: the device-opp being added
159 *
160 * Dynamically adds device specific directory in debugfs 'opp' directory. If the
161 * device-opp is shared with other devices, then links will be created for all
162 * devices except the first.
163 */
164void opp_debug_register(struct opp_device *opp_dev, struct opp_table *opp_table)
165{
166    if (opp_table->dentry) {
167        opp_list_debug_create_link(opp_dev, opp_table);
168    } else {
169        opp_list_debug_create_dir(opp_dev, opp_table);
170    }
171}
172
173static void opp_migrate_dentry(struct opp_device *opp_dev, struct opp_table *opp_table)
174{
175    struct opp_device *new_dev;
176    const struct device *dev;
177    struct dentry *dentry;
178
179    /* Look for next opp-dev */
180    list_for_each_entry(new_dev, &opp_table->dev_list, node) if (new_dev != opp_dev) break;
181
182    /* new_dev is guaranteed to be valid here */
183    dev = new_dev->dev;
184    debugfs_remove_recursive(new_dev->dentry);
185
186    opp_set_dev_name(dev, opp_table->dentry_name);
187
188    dentry = debugfs_rename(rootdir, opp_dev->dentry, rootdir, opp_table->dentry_name);
189    if (!dentry) {
190        dev_err(dev, "%s: Failed to rename link from: %s to %s\n", __func__, dev_name(opp_dev->dev), dev_name(dev));
191        return;
192    }
193
194    new_dev->dentry = dentry;
195    opp_table->dentry = dentry;
196}
197
198/**
199 * opp_debug_unregister - remove a device opp node from debugfs opp directory
200 * @opp_dev: opp-dev pointer for device
201 * @opp_table: the device-opp being removed
202 *
203 * Dynamically removes device specific directory from debugfs 'opp' directory.
204 */
205void opp_debug_unregister(struct opp_device *opp_dev, struct opp_table *opp_table)
206{
207    if (opp_dev->dentry == opp_table->dentry) {
208        /* Move the real dentry object under another device */
209        if (!list_is_singular(&opp_table->dev_list)) {
210            opp_migrate_dentry(opp_dev, opp_table);
211            goto out;
212        }
213        opp_table->dentry = NULL;
214    }
215
216    debugfs_remove_recursive(opp_dev->dentry);
217
218out:
219    opp_dev->dentry = NULL;
220}
221
222static int opp_summary_show(struct seq_file *s, void *data)
223{
224    struct list_head *lists = (struct list_head *)s->private;
225    struct opp_table *opp_table;
226    struct dev_pm_opp *opp;
227
228    mutex_lock(&opp_table_lock);
229
230    seq_puts(s, " device                rate(Hz)    target(uV)    min(uV)    max(uV)\n");
231    seq_puts(s, "-------------------------------------------------------------------\n");
232
233    list_for_each_entry(opp_table, lists, node)
234    {
235        seq_printf(s, " %s\n", opp_table->dentry_name);
236        mutex_lock(&opp_table->lock);
237        list_for_each_entry(opp, &opp_table->opp_list, node)
238        {
239            seq_printf(s, "%31lu %12lu %11lu %11lu\n", opp->rate, opp->supplies[0].u_volt, opp->supplies[0].u_volt_min,
240                       opp->supplies[0].u_volt_max);
241        }
242        mutex_unlock(&opp_table->lock);
243    }
244
245    mutex_unlock(&opp_table_lock);
246
247    return 0;
248}
249
250static int opp_summary_open(struct inode *inode, struct file *file)
251{
252    return single_open(file, opp_summary_show, inode->i_private);
253}
254
255static const struct file_operations opp_summary_fops = {
256    .open = opp_summary_open,
257    .read = seq_read,
258    .llseek = seq_lseek,
259    .release = single_release,
260};
261
262static int __init opp_debug_init(void)
263{
264    /* Create /sys/kernel/debug/opp directory */
265    rootdir = debugfs_create_dir("opp", NULL);
266
267    debugfs_create_file("opp_summary", 0444, rootdir, &opp_tables, &opp_summary_fops);
268
269    return 0;
270}
271core_initcall(opp_debug_init);
272