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
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
|
/*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* Copyright 2004 Wu Qi Ming <gokimi@msn.com>
* Copyright (C) 2007 John Crispin <blogic@openwrt.org>
*/
#include <linux/version.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/timer.h>
#include <linux/fs.h>
#include <linux/errno.h>
#include <linux/proc_fs.h>
#include <linux/stat.h>
#include <linux/tty.h>
#include <linux/selection.h>
#include <linux/kmod.h>
#include <linux/vmalloc.h>
#include <linux/kdev_t.h>
#include <linux/ioctl.h>
#include <asm/uaccess.h>
#include <asm/system.h>
#include <linux/platform_device.h>
#include <asm/amazon/amazon.h>
#include <asm/amazon/amazon_wdt.h>
#define DRV_NAME "AMAZON WDT:"
#undef AMAZON_WDT_DEBUG
static int amazon_wdt_isopen = 0;
#ifdef AMAZON_WDT_DEBUG
static struct proc_dir_entry* amazon_wdt_dir;
#endif
int wdt_enable(int timeout)
{
u32 hard_psw, ffpi;
int reload_value, divider = 1;
ffpi = amazon_get_fpi_hz();
reload_value = 65536 - timeout * ffpi / 256;
if (reload_value < 0) {
divider = 0;
reload_value = 65536 - timeout * ffpi / 16384;
}
if (reload_value < 0){
printk(KERN_INFO DRV_NAME "timeout too large %d\n", timeout);
return -EINVAL;
}
printk(KERN_INFO DRV_NAME "timeout:%d reload_value: %8x\n", timeout, reload_value);
hard_psw = (amazon_readl(AMAZON_WDT_CON0) & 0xffffff01) +
(amazon_readl(AMAZON_WDT_CON1) & 0xc) + 0xf0;
amazon_writel(hard_psw, AMAZON_WDT_CON0);
wmb();
amazon_writel((hard_psw & 0xff00) + (reload_value << 16) + 0xf2, AMAZON_WDT_CON0);
wmb();
amazon_writel(divider << 2, AMAZON_WDT_CON1);
wmb();
hard_psw = (amazon_readl(AMAZON_WDT_CON0) & 0xffffff01) +
(amazon_readl(AMAZON_WDT_CON1) & 0xc) + 0xf0;
amazon_writel(hard_psw, AMAZON_WDT_CON0);
wmb();
amazon_writel_masked(AMAZON_WDT_CON0, 0xff, 0xf3);
wmb();
return 0;
}
void wdt_disable(void)
{
u32 hard_psw = 0;
hard_psw = (amazon_readl(AMAZON_WDT_CON0) & 0xffffff01) +
(amazon_readl(AMAZON_WDT_CON1) & 0xc) + 0xf0;
amazon_writel(hard_psw, AMAZON_WDT_CON0);
wmb();
amazon_writel_masked(AMAZON_WDT_CON0, 0xff, 0xf2);
wmb();
amazon_writel_masked(AMAZON_WDT_CON1, 0x8, 0x8);
wmb();
hard_psw=(amazon_readl(AMAZON_WDT_CON0) & 0xffffff01) +
(amazon_readl(AMAZON_WDT_CON1) & 0xc) + 0xf0;
amazon_writel(hard_psw, AMAZON_WDT_CON0);
wmb();
amazon_writel_masked(AMAZON_WDT_CON0, 0xff, 0xf3);
wmb();
return;
}
#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,36))
static long wdt_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
#else
static int wdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
#endif
{
int result=0;
static int timeout=-1;
switch(cmd){
case AMAZON_WDT_IOC_START:
printk(KERN_INFO DRV_NAME "enable watch dog timer!\n");
if (copy_from_user((void*)&timeout, (void*)arg, sizeof (int))) {
printk(KERN_INFO DRV_NAME "invalid argument\n");
result=-EINVAL;
} else if ((result = wdt_enable(timeout)) < 0) {
timeout = -1;
}
break;
case AMAZON_WDT_IOC_STOP:
printk(KERN_INFO DRV_NAME "disable watch dog timer\n");
timeout = -1;
wdt_disable();
break;
case AMAZON_WDT_IOC_PING:
if (timeout < 0) {
result = -EIO;
} else {
result = wdt_enable(timeout);
}
break;
default:
result=-EINVAL;
break;
}
return result;
}
static ssize_t wdt_read(struct file *file, char *buf, size_t count, loff_t *offset)
{
return 0;
}
static ssize_t wdt_write(struct file *file, const char *buf, size_t count, loff_t *offset)
{
return count;
}
static int wdt_open(struct inode *inode, struct file *file)
{
if (amazon_wdt_isopen == 1)
return -EBUSY;
amazon_wdt_isopen = 1;
printk(KERN_INFO DRV_NAME "opened\n");
return 0;
}
static int wdt_release(struct inode *inode, struct file *file)
{
amazon_wdt_isopen = 0;
printk(KERN_INFO DRV_NAME "closed\n");
return 0;
}
#ifdef AMAZON_WDT_DEBUG
int wdt_register_proc_read(char *buf, char **start, off_t offset,
int count, int *eof, void *data)
{
int len=0;
len+=sprintf(buf+len,"NMISR: 0x%08x\n",AMAZON_WDT_REG32(AMAZON_WDT_NMISR));
len+=sprintf(buf+len,"RST_REQ: 0x%08x\n",AMAZON_WDT_REG32(AMAZON_RST_REQ));
len+=sprintf(buf+len,"RST_SR: 0x%08x\n",AMAZON_WDT_REG32(AMAZON_RST_SR));
len+=sprintf(buf+len,"WDT_CON0: 0x%08x\n",AMAZON_WDT_REG32(AMAZON_WDT_CON0));
len+=sprintf(buf+len,"WDT_CON1: 0x%08x\n",AMAZON_WDT_REG32(AMAZON_WDT_CON1));
len+=sprintf(buf+len,"WDT_SR: 0x%08x\n",AMAZON_WDT_REG32(AMAZON_WDT_SR));
*eof = 1;
return len;
}
#endif
static struct file_operations wdt_fops = {
read: wdt_read,
write: wdt_write,
#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,36))
unlocked_ioctl: wdt_ioctl,
#else
ioctl: wdt_ioctl,
#endif
open: wdt_open,
release: wdt_release,
};
static int __init amazon_wdt_probe(struct platform_device *dev)
{
int result = result = register_chrdev(0, "watchdog", &wdt_fops);
if (result < 0) {
printk(KERN_INFO DRV_NAME "cannot register device\n");
return result;
}
#ifdef AMAZON_WDT_DEBUG
amazon_wdt_dir=proc_mkdir("amazon_wdt",NULL);
create_proc_read_entry("wdt_register", 0, amazon_wdt_dir,
wdt_register_proc_read, NULL);
#endif
amazon_wdt_isopen=0;
printk(KERN_INFO DRV_NAME "driver loaded but inactive\n");
return 0;
}
static int amazon_wdt_remove(struct platform_device *dev)
{
unregister_chrdev(0, "watchdog");
#ifdef AMAZON_WDT_DEBUG
remove_proc_entry("wdt_register", amazon_wdt_dir);
remove_proc_entry("amazon_wdt", NULL);
#endif
printk(KERN_INFO DRV_NAME "unregistered\n");
return 0;
}
static struct platform_driver amazon_wdt_driver = {
.probe = amazon_wdt_probe,
.remove = amazon_wdt_remove,
.driver = {
.name = "amazon_wdt",
.owner = THIS_MODULE,
},
};
static int __init amazon_wdt_init(void)
{
int ret = platform_driver_register(&amazon_wdt_driver);
if (ret)
printk(KERN_WARNING "amazon_wdt: error registering platfom driver!\n");
return ret;
}
static void __exit amazon_wdt_exit(void)
{
platform_driver_unregister(&amazon_wdt_driver);
}
module_init(amazon_wdt_init);
module_exit(amazon_wdt_exit);
MODULE_LICENSE ("GPL");
MODULE_AUTHOR("Infineon / John Crispin <blogic@openwrt.org>");
MODULE_DESCRIPTION("AMAZON WDT driver");
|
