danube to ifxmips transition
[openwrt/svn-archive/archive.git] / target / linux / ifxmips / files / drivers / char / watchdog / danube_wdt.c
1 /*
2 * This program is free software; you can redistribute it and/or modify
3 * it under the terms of the GNU General Public License as published by
4 * the Free Software Foundation; either version 2 of the License, or
5 * (at your option) any later version.
6 *
7 * This program is distributed in the hope that it will be useful,
8 * but WITHOUT ANY WARRANTY; without even the implied warranty of
9 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
10 * GNU General Public License for more details.
11 *
12 * You should have received a copy of the GNU General Public License
13 * along with this program; if not, write to the Free Software
14 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
15 *
16 * Copyright (C) 2006 infineon
17 * Copyright (C) 2007 John Crispin <blogic@openwrt.org>
18 *
19 */
20
21 #include <asm/uaccess.h>
22 #include <linux/errno.h>
23 #include <linux/proc_fs.h>
24 #include <linux/ioctl.h>
25 #include <linux/module.h>
26 #include <asm-mips/ifxmips/ifxmips_wdt.h>
27 #include <asm-mips/ifxmips/ifxmips.h>
28
29
30 // TODO remove magic numbers and weirdo macros
31
32 extern unsigned int ifxmips_get_fpi_hz (void);
33
34 static int ifxmips_wdt_inuse = 0;
35 static int ifxmips_wdt_major = 0;
36
37 int
38 ifxmips_wdt_enable (unsigned int timeout)
39 {
40 unsigned int wdt_cr = 0;
41 unsigned int wdt_reload = 0;
42 unsigned int wdt_clkdiv, wdt_pwl, ffpi;
43 int retval = 0;
44
45 /* clock divider & prewarning limit */
46 wdt_clkdiv = 1 << (7 * IFXMIPS_BIU_WDT_CR_CLKDIV_GET(readl(IFXMIPS_BIU_WDT_CR)));
47 wdt_pwl = 0x8000 >> IFXMIPS_BIU_WDT_CR_PWL_GET(readl(IFXMIPS_BIU_WDT_CR));
48
49 //TODO
50 printk("WARNING FUNCTION CALL MISSING!!!");
51 //ffpi = cgu_get_io_region_clock();
52 printk("cpu clock = %d\n", ffpi);
53
54 /* caculate reload value */
55 wdt_reload = (timeout * (ffpi / wdt_clkdiv)) + wdt_pwl;
56
57 printk("wdt_pwl=0x%x, wdt_clkdiv=%d, ffpi=%d, wdt_reload = 0x%x\n",
58 wdt_pwl, wdt_clkdiv, ffpi, wdt_reload);
59
60 if (wdt_reload > 0xFFFF)
61 {
62 printk ("timeout too large %d\n", timeout);
63 retval = -EINVAL;
64 goto out;
65 }
66
67 /* Write first part of password access */
68 writel(IFXMIPS_BIU_WDT_CR_PW_SET(IFXMIPS_WDT_PW1), IFXMIPS_BIU_WDT_CR);
69
70 wdt_cr = readl(IFXMIPS_BIU_WDT_CR);
71 wdt_cr &= (!IFXMIPS_BIU_WDT_CR_PW_SET(0xff) &
72 !IFXMIPS_BIU_WDT_CR_PWL_SET(0x3) &
73 !IFXMIPS_BIU_WDT_CR_CLKDIV_SET(0x3) &
74 !IFXMIPS_BIU_WDT_CR_RELOAD_SET(0xffff));
75
76 wdt_cr |= (IFXMIPS_BIU_WDT_CR_PW_SET(IFXMIPS_WDT_PW2) |
77 IFXMIPS_BIU_WDT_CR_PWL_SET(IFXMIPS_BIU_WDT_CR_PWL_GET(readl(IFXMIPS_BIU_WDT_CR))) |
78 IFXMIPS_BIU_WDT_CR_CLKDIV_SET(IFXMIPS_BIU_WDT_CR_CLKDIV_GET(readl(IFXMIPS_BIU_WDT_CR))) |
79 IFXMIPS_BIU_WDT_CR_RELOAD_SET(wdt_reload) |
80 IFXMIPS_BIU_WDT_CR_GEN);
81
82 writel(wdt_cr, IFXMIPS_BIU_WDT_CR);
83
84 printk("watchdog enabled\n");
85
86 out:
87 return retval;
88 }
89
90 void
91 ifxmips_wdt_disable (void)
92 {
93 writel(IFXMIPS_BIU_WDT_CR_PW_SET(IFXMIPS_WDT_PW1), IFXMIPS_BIU_WDT_CR);
94 writel(IFXMIPS_BIU_WDT_CR_PW_SET(IFXMIPS_WDT_PW2), IFXMIPS_BIU_WDT_CR);
95
96 printk("watchdog disabled\n");
97 }
98
99 /* passed LPEN or DSEN */
100 void
101 ifxmips_wdt_enable_feature (int en, int type)
102 {
103 unsigned int wdt_cr = 0;
104
105 writel(IFXMIPS_BIU_WDT_CR_PW_SET(IFXMIPS_WDT_PW1), IFXMIPS_BIU_WDT_CR);
106
107 wdt_cr = readl(IFXMIPS_BIU_WDT_CR);
108
109 if (en)
110 {
111 wdt_cr &= (~IFXMIPS_BIU_WDT_CR_PW_SET(0xff));
112 wdt_cr |= (IFXMIPS_BIU_WDT_CR_PW_SET(IFXMIPS_WDT_PW2) | type);
113 } else {
114 wdt_cr &= (~IFXMIPS_BIU_WDT_CR_PW_SET(0xff) & ~type);
115 wdt_cr |= IFXMIPS_BIU_WDT_CR_PW_SET(IFXMIPS_WDT_PW2);
116 }
117
118 writel(wdt_cr, IFXMIPS_BIU_WDT_CR);
119 }
120
121 void
122 ifxmips_wdt_prewarning_limit (int pwl)
123 {
124 unsigned int wdt_cr = 0;
125
126 wdt_cr = readl(IFXMIPS_BIU_WDT_CR);
127 writel(IFXMIPS_BIU_WDT_CR_PW_SET(IFXMIPS_WDT_PW1), IFXMIPS_BIU_WDT_CR);
128
129 wdt_cr &= 0xf300ffff;
130 wdt_cr |= (IFXMIPS_BIU_WDT_CR_PW_SET(IFXMIPS_WDT_PW2) | IFXMIPS_BIU_WDT_CR_PWL_SET(pwl));
131
132 /* Set reload value in second password access */
133 writel(wdt_cr, IFXMIPS_BIU_WDT_CR);
134 }
135
136 void
137 ifxmips_wdt_set_clkdiv (int clkdiv)
138 {
139 unsigned int wdt_cr = 0;
140
141 wdt_cr = readl(IFXMIPS_BIU_WDT_CR);
142 writel(IFXMIPS_BIU_WDT_CR_PW_SET(IFXMIPS_WDT_PW1), IFXMIPS_BIU_WDT_CR);
143
144 wdt_cr &= 0xfc00ffff;
145 wdt_cr |= (IFXMIPS_BIU_WDT_CR_PW_SET(IFXMIPS_WDT_PW2) | IFXMIPS_BIU_WDT_CR_CLKDIV_SET(clkdiv));
146
147 /* Set reload value in second password access */
148 writel(wdt_cr, IFXMIPS_BIU_WDT_CR);
149 }
150
151 static int
152 ifxmips_wdt_ioctl (struct inode *inode, struct file *file, unsigned int cmd,
153 unsigned long arg)
154 {
155 int result = 0;
156 static int timeout = -1;
157 unsigned int user_arg;
158
159 if ((cmd != IFXMIPS_WDT_IOC_STOP) && (cmd != IFXMIPS_WDT_IOC_PING) && (cmd != IFXMIPS_WDT_IOC_GET_STATUS))
160 {
161 if (copy_from_user((void *) &user_arg, (void *) arg, sizeof (int))){
162 result = -EINVAL;
163 goto out;
164 }
165 }
166
167 switch (cmd)
168 {
169 case IFXMIPS_WDT_IOC_START:
170 if ((result = ifxmips_wdt_enable(user_arg)) < 0)
171 timeout = -1;
172 else
173 timeout = user_arg;
174 break;
175
176 case IFXMIPS_WDT_IOC_STOP:
177 printk("disable watch dog timer\n");
178 ifxmips_wdt_disable();
179 break;
180
181 case IFXMIPS_WDT_IOC_PING:
182 if (timeout < 0)
183 result = -EIO;
184 else
185 result = ifxmips_wdt_enable(timeout);
186 break;
187
188 case IFXMIPS_WDT_IOC_GET_STATUS:
189 user_arg = readl(IFXMIPS_BIU_WDT_SR);
190 copy_to_user((int*)arg, (int*)&user_arg, sizeof(int));
191 break;
192
193 case IFXMIPS_WDT_IOC_SET_PWL:
194 ifxmips_wdt_prewarning_limit(user_arg);
195 break;
196
197 case IFXMIPS_WDT_IOC_SET_DSEN:
198 ifxmips_wdt_enable_feature(user_arg, IFXMIPS_BIU_WDT_CR_DSEN);
199 break;
200
201 case IFXMIPS_WDT_IOC_SET_LPEN:
202 ifxmips_wdt_enable_feature(user_arg, IFXMIPS_BIU_WDT_CR_LPEN);
203 break;
204
205 case IFXMIPS_WDT_IOC_SET_CLKDIV:
206 ifxmips_wdt_set_clkdiv(user_arg);
207 break;
208
209 default:
210 printk("unknown watchdog iotcl\n");
211 }
212
213 out:
214 return result;
215 }
216
217 static int
218 ifxmips_wdt_open (struct inode *inode, struct file *file)
219 {
220 if (ifxmips_wdt_inuse)
221 return -EBUSY;
222
223 ifxmips_wdt_inuse = 1;
224
225 return 0;
226 }
227
228 static int
229 ifxmips_wdt_release (struct inode *inode, struct file *file)
230 {
231 ifxmips_wdt_inuse = 0;
232
233 return 0;
234 }
235
236 int
237 ifxmips_wdt_register_proc_read (char *buf, char **start, off_t offset, int count,
238 int *eof, void *data)
239 {
240 int len = 0;
241
242 len += sprintf (buf + len, "IFXMIPS_BIU_WDT_PROC_READ\n");
243 len += sprintf (buf + len, "IFXMIPS_BIU_WDT_CR(0x%08x) : 0x%08x\n",
244 (unsigned int)IFXMIPS_BIU_WDT_CR, readl(IFXMIPS_BIU_WDT_CR));
245 len += sprintf (buf + len, "IFXMIPS_BIU_WDT_SR(0x%08x) : 0x%08x\n",
246 (unsigned int)IFXMIPS_BIU_WDT_SR, readl(IFXMIPS_BIU_WDT_SR));
247
248 *eof = 1;
249
250 return len;
251 }
252
253 static struct file_operations wdt_fops = {
254 .owner = THIS_MODULE,
255 .ioctl = ifxmips_wdt_ioctl,
256 .open = ifxmips_wdt_open,
257 .release = ifxmips_wdt_release,
258 };
259
260 int __init
261 ifxmips_wdt_init_module (void)
262 {
263 ifxmips_wdt_major = register_chrdev(0, "wdt", &wdt_fops);
264
265 if (ifxmips_wdt_major < 0)
266 {
267 printk("cannot register watchdog device\n");
268
269 return -EINVAL;
270 }
271
272 create_proc_read_entry("ifxmips_wdt", 0, NULL, ifxmips_wdt_register_proc_read, NULL);
273
274 printk("ifxmips watchdog loaded\n");
275
276 return 0;
277 }
278
279 void
280 ifxmips_wdt_cleanup_module (void)
281 {
282 unregister_chrdev(ifxmips_wdt_major, "wdt");
283 remove_proc_entry("ifxmips_wdt", NULL);
284 }
285
286 module_init(ifxmips_wdt_init_module);
287 module_exit(ifxmips_wdt_cleanup_module);