1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
|
/*
* avila-wdt.c
* Copyright (C) 2009 Felix Fietkau <nbd@openwrt.org>
*
* based on:
* drivers/char/watchdog/ixp4xx_wdt.c
*
* Watchdog driver for Intel IXP4xx network processors
*
* Author: Deepak Saxena <dsaxena@plexity.net>
*
* Copyright 2004 (c) MontaVista, Software, Inc.
* Based on sa1100 driver, Copyright (C) 2000 Oleg Drokin <green@crimea.edu>
*
* This file is licensed under the terms of the GNU General Public
* License version 2. This program is licensed "as is" without any
* warranty of any kind, whether express or implied.
*/
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/miscdevice.h>
#include <linux/watchdog.h>
#include <linux/init.h>
#include <linux/bitops.h>
#include <linux/uaccess.h>
#include <mach/hardware.h>
static int nowayout = WATCHDOG_NOWAYOUT;
static int heartbeat = 20; /* (secs) Default is 20 seconds */
static unsigned long wdt_status;
static atomic_t wdt_counter;
struct timer_list wdt_timer;
#define WDT_IN_USE 0
#define WDT_OK_TO_CLOSE 1
#define WDT_RUNNING 2
static void wdt_refresh(unsigned long data)
{
if (test_bit(WDT_RUNNING, &wdt_status)) {
if (atomic_dec_and_test(&wdt_counter)) {
printk(KERN_WARNING "Avila watchdog expired, expect a reboot soon!\n");
clear_bit(WDT_RUNNING, &wdt_status);
return;
}
}
/* strobe to the watchdog */
gpio_line_set(14, IXP4XX_GPIO_HIGH);
gpio_line_set(14, IXP4XX_GPIO_LOW);
mod_timer(&wdt_timer, jiffies + msecs_to_jiffies(500));
}
static void wdt_enable(void)
{
atomic_set(&wdt_counter, heartbeat * 2);
/* Disable clock generator output on GPIO 14/15 */
*IXP4XX_GPIO_GPCLKR &= ~(1 << 8);
/* activate GPIO 14 out */
gpio_line_config(14, IXP4XX_GPIO_OUT);
gpio_line_set(14, IXP4XX_GPIO_LOW);
if (!test_bit(WDT_RUNNING, &wdt_status))
wdt_refresh(0);
set_bit(WDT_RUNNING, &wdt_status);
}
static void wdt_disable(void)
{
/* NB: we can't turn off the watchdog anymore, so we
* have to keep running the strobe timer without decrementing
* the counter */
clear_bit(WDT_RUNNING, &wdt_status);
}
static int avila_wdt_open(struct inode *inode, struct file *file)
{
if (test_and_set_bit(WDT_IN_USE, &wdt_status))
return -EBUSY;
clear_bit(WDT_OK_TO_CLOSE, &wdt_status);
wdt_enable();
return nonseekable_open(inode, file);
}
static ssize_t
avila_wdt_write(struct file *file, const char *data, size_t len, loff_t *ppos)
{
if (len) {
if (!nowayout) {
size_t i;
clear_bit(WDT_OK_TO_CLOSE, &wdt_status);
for (i = 0; i != len; i++) {
char c;
if (get_user(c, data + i))
return -EFAULT;
if (c == 'V')
set_bit(WDT_OK_TO_CLOSE, &wdt_status);
}
}
wdt_enable();
}
return len;
}
static struct watchdog_info ident = {
.options = WDIOF_CARDRESET | WDIOF_MAGICCLOSE |
WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
.identity = "Avila Watchdog",
};
static long avila_wdt_ioctl(struct file *file, unsigned int cmd,
unsigned long arg)
{
int ret = -ENOTTY;
int time;
switch (cmd) {
case WDIOC_GETSUPPORT:
ret = copy_to_user((struct watchdog_info *)arg, &ident,
sizeof(ident)) ? -EFAULT : 0;
break;
case WDIOC_GETSTATUS:
ret = put_user(0, (int *)arg);
break;
case WDIOC_KEEPALIVE:
wdt_enable();
ret = 0;
break;
case WDIOC_SETTIMEOUT:
ret = get_user(time, (int *)arg);
if (ret)
break;
if (time <= 0 || time > 60) {
ret = -EINVAL;
break;
}
heartbeat = time;
wdt_enable();
/* Fall through */
case WDIOC_GETTIMEOUT:
ret = put_user(heartbeat, (int *)arg);
break;
}
return ret;
}
static int avila_wdt_release(struct inode *inode, struct file *file)
{
if (test_bit(WDT_OK_TO_CLOSE, &wdt_status))
wdt_disable();
else
printk(KERN_CRIT "WATCHDOG: Device closed unexpectedly - "
"timer will not stop\n");
clear_bit(WDT_IN_USE, &wdt_status);
clear_bit(WDT_OK_TO_CLOSE, &wdt_status);
return 0;
}
static const struct file_operations avila_wdt_fops = {
.owner = THIS_MODULE,
.llseek = no_llseek,
.write = avila_wdt_write,
.unlocked_ioctl = avila_wdt_ioctl,
.open = avila_wdt_open,
.release = avila_wdt_release,
};
static struct miscdevice avila_wdt_miscdev = {
.minor = WATCHDOG_MINOR + 1,
.name = "avila_watchdog",
.fops = &avila_wdt_fops,
};
static int __init avila_wdt_init(void)
{
int ret;
init_timer(&wdt_timer);
wdt_timer.expires = 0;
wdt_timer.data = 0;
wdt_timer.function = wdt_refresh;
ret = misc_register(&avila_wdt_miscdev);
if (ret == 0)
printk(KERN_INFO "Avila Watchdog Timer: heartbeat %d sec\n",
heartbeat);
return ret;
}
static void __exit avila_wdt_exit(void)
{
misc_deregister(&avila_wdt_miscdev);
}
module_init(avila_wdt_init);
module_exit(avila_wdt_exit);
MODULE_AUTHOR("Felix Fietkau <nbd@openwrt.org>");
MODULE_DESCRIPTION("Gateworks Avila Hardware Watchdog");
module_param(heartbeat, int, 0);
MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds (default 20s)");
module_param(nowayout, int, 0);
MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started");
MODULE_LICENSE("GPL");
MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
|
