blob: 70277a530133451dd298281c214f91bcc9d66006 [file] [log] [blame]
Ohad Ben-Cohen6391a702011-10-20 17:24:15 +02001/*
2 * Remote Processor Framework
3 *
4 * Copyright (C) 2011 Texas Instruments, Inc.
5 * Copyright (C) 2011 Google, Inc.
6 *
7 * Ohad Ben-Cohen <ohad@wizery.com>
8 * Mark Grosen <mgrosen@ti.com>
9 * Brian Swetland <swetland@google.com>
10 * Fernando Guzman Lugo <fernando.lugo@ti.com>
11 * Suman Anna <s-anna@ti.com>
12 * Robert Tivy <rtivy@ti.com>
13 * Armando Uribe De Leon <x0095078@ti.com>
14 *
15 * This program is free software; you can redistribute it and/or
16 * modify it under the terms of the GNU General Public License
17 * version 2 as published by the Free Software Foundation.
18 *
19 * This program is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 * GNU General Public License for more details.
23 */
24
25#define pr_fmt(fmt) "%s: " fmt, __func__
26
27#include <linux/kernel.h>
28#include <linux/debugfs.h>
29#include <linux/remoteproc.h>
30#include <linux/device.h>
31
32/* remoteproc debugfs parent dir */
33static struct dentry *rproc_dbg;
34
35/*
36 * Some remote processors may support dumping trace logs into a shared
37 * memory buffer. We expose this trace buffer using debugfs, so users
38 * can easily tell what's going on remotely.
39 *
40 * We will most probably improve the rproc tracing facilities later on,
41 * but this kind of lightweight and simple mechanism is always good to have,
42 * as it provides very early tracing with little to no dependencies at all.
43 */
44static ssize_t rproc_trace_read(struct file *filp, char __user *userbuf,
45 size_t count, loff_t *ppos)
46{
47 struct rproc_mem_entry *trace = filp->private_data;
48 int len = strnlen(trace->va, trace->len);
49
50 return simple_read_from_buffer(userbuf, count, ppos, trace->va, len);
51}
52
53static int rproc_open_generic(struct inode *inode, struct file *file)
54{
55 file->private_data = inode->i_private;
56
57 return 0;
58}
59
60static const struct file_operations trace_rproc_ops = {
61 .read = rproc_trace_read,
62 .open = rproc_open_generic,
63 .llseek = generic_file_llseek,
64};
65
66/*
67 * A state-to-string lookup table, for exposing a human readable state
68 * via debugfs. Always keep in sync with enum rproc_state
69 */
70static const char * const rproc_state_string[] = {
71 "offline",
72 "suspended",
73 "running",
74 "crashed",
75 "invalid",
76};
77
78/* expose the state of the remote processor via debugfs */
79static ssize_t rproc_state_read(struct file *filp, char __user *userbuf,
80 size_t count, loff_t *ppos)
81{
82 struct rproc *rproc = filp->private_data;
83 unsigned int state;
84 char buf[30];
85 int i;
86
87 state = rproc->state > RPROC_LAST ? RPROC_LAST : rproc->state;
88
89 i = snprintf(buf, 30, "%.28s (%d)\n", rproc_state_string[state],
90 rproc->state);
91
92 return simple_read_from_buffer(userbuf, count, ppos, buf, i);
93}
94
95static const struct file_operations rproc_state_ops = {
96 .read = rproc_state_read,
97 .open = rproc_open_generic,
98 .llseek = generic_file_llseek,
99};
100
101/* expose the name of the remote processor via debugfs */
102static ssize_t rproc_name_read(struct file *filp, char __user *userbuf,
103 size_t count, loff_t *ppos)
104{
105 struct rproc *rproc = filp->private_data;
106 /* need room for the name, a newline and a terminating null */
107 char buf[100];
108 int i;
109
110 i = snprintf(buf, sizeof(buf), "%.98s\n", rproc->name);
111
112 return simple_read_from_buffer(userbuf, count, ppos, buf, i);
113}
114
115static const struct file_operations rproc_name_ops = {
116 .read = rproc_name_read,
117 .open = rproc_open_generic,
118 .llseek = generic_file_llseek,
119};
120
121void rproc_remove_trace_file(struct dentry *tfile)
122{
123 debugfs_remove(tfile);
124}
125
126struct dentry *rproc_create_trace_file(const char *name, struct rproc *rproc,
127 struct rproc_mem_entry *trace)
128{
129 struct dentry *tfile;
130
131 tfile = debugfs_create_file(name, 0400, rproc->dbg_dir,
132 trace, &trace_rproc_ops);
133 if (!tfile) {
134 dev_err(rproc->dev, "failed to create debugfs trace entry\n");
135 return NULL;
136 }
137
138 return tfile;
139}
140
141void rproc_delete_debug_dir(struct rproc *rproc)
142{
143 if (!rproc->dbg_dir)
144 return;
145
146 debugfs_remove_recursive(rproc->dbg_dir);
147}
148
149void rproc_create_debug_dir(struct rproc *rproc)
150{
151 struct device *dev = rproc->dev;
152
153 if (!rproc_dbg)
154 return;
155
156 rproc->dbg_dir = debugfs_create_dir(dev_name(dev), rproc_dbg);
157 if (!rproc->dbg_dir)
158 return;
159
160 debugfs_create_file("name", 0400, rproc->dbg_dir,
161 rproc, &rproc_name_ops);
162 debugfs_create_file("state", 0400, rproc->dbg_dir,
163 rproc, &rproc_state_ops);
164}
165
166void __init rproc_init_debugfs(void)
167{
168 if (debugfs_initialized()) {
169 rproc_dbg = debugfs_create_dir(KBUILD_MODNAME, NULL);
170 if (!rproc_dbg)
171 pr_err("can't create debugfs dir\n");
172 }
173}
174
175void __exit rproc_exit_debugfs(void)
176{
177 if (rproc_dbg)
178 debugfs_remove(rproc_dbg);
179}