diff options
author | Wim Van Sebroeck <wim@iguana.be> | 2007-08-17 04:38:02 -0400 |
---|---|---|
committer | Wim Van Sebroeck <wim@iguana.be> | 2007-10-18 06:39:03 -0400 |
commit | b7e04f8c61a46d742de23af5d7ca2b41b33e40ac (patch) | |
tree | c52a7ea568648e2d8ed0d423098b42298de2058b /drivers/watchdog/machzwd.c | |
parent | d85714d81cc0408daddb68c10f7fd69eafe7c213 (diff) |
mv watchdog tree under drivers
move watchdog tree from drivers/char/watchdog to drivers/watchdog.
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Diffstat (limited to 'drivers/watchdog/machzwd.c')
-rw-r--r-- | drivers/watchdog/machzwd.c | 489 |
1 files changed, 489 insertions, 0 deletions
diff --git a/drivers/watchdog/machzwd.c b/drivers/watchdog/machzwd.c new file mode 100644 index 000000000000..6d35bb112a5f --- /dev/null +++ b/drivers/watchdog/machzwd.c | |||
@@ -0,0 +1,489 @@ | |||
1 | /* | ||
2 | * MachZ ZF-Logic Watchdog Timer driver for Linux | ||
3 | * | ||
4 | * | ||
5 | * This program is free software; you can redistribute it and/or | ||
6 | * modify it under the terms of the GNU General Public License | ||
7 | * as published by the Free Software Foundation; either version | ||
8 | * 2 of the License, or (at your option) any later version. | ||
9 | * | ||
10 | * The author does NOT admit liability nor provide warranty for | ||
11 | * any of this software. This material is provided "AS-IS" in | ||
12 | * the hope that it may be useful for others. | ||
13 | * | ||
14 | * Author: Fernando Fuganti <fuganti@conectiva.com.br> | ||
15 | * | ||
16 | * Based on sbc60xxwdt.c by Jakob Oestergaard | ||
17 | * | ||
18 | * | ||
19 | * We have two timers (wd#1, wd#2) driven by a 32 KHz clock with the | ||
20 | * following periods: | ||
21 | * wd#1 - 2 seconds; | ||
22 | * wd#2 - 7.2 ms; | ||
23 | * After the expiration of wd#1, it can generate a NMI, SCI, SMI, or | ||
24 | * a system RESET and it starts wd#2 that unconditionaly will RESET | ||
25 | * the system when the counter reaches zero. | ||
26 | * | ||
27 | * 14-Dec-2001 Matt Domsch <Matt_Domsch@dell.com> | ||
28 | * Added nowayout module option to override CONFIG_WATCHDOG_NOWAYOUT | ||
29 | */ | ||
30 | |||
31 | #include <linux/module.h> | ||
32 | #include <linux/moduleparam.h> | ||
33 | #include <linux/types.h> | ||
34 | #include <linux/timer.h> | ||
35 | #include <linux/jiffies.h> | ||
36 | #include <linux/miscdevice.h> | ||
37 | #include <linux/watchdog.h> | ||
38 | #include <linux/fs.h> | ||
39 | #include <linux/ioport.h> | ||
40 | #include <linux/notifier.h> | ||
41 | #include <linux/reboot.h> | ||
42 | #include <linux/init.h> | ||
43 | |||
44 | #include <asm/io.h> | ||
45 | #include <asm/uaccess.h> | ||
46 | #include <asm/system.h> | ||
47 | |||
48 | /* ports */ | ||
49 | #define ZF_IOBASE 0x218 | ||
50 | #define INDEX 0x218 | ||
51 | #define DATA_B 0x219 | ||
52 | #define DATA_W 0x21A | ||
53 | #define DATA_D 0x21A | ||
54 | |||
55 | /* indexes */ /* size */ | ||
56 | #define ZFL_VERSION 0x02 /* 16 */ | ||
57 | #define CONTROL 0x10 /* 16 */ | ||
58 | #define STATUS 0x12 /* 8 */ | ||
59 | #define COUNTER_1 0x0C /* 16 */ | ||
60 | #define COUNTER_2 0x0E /* 8 */ | ||
61 | #define PULSE_LEN 0x0F /* 8 */ | ||
62 | |||
63 | /* controls */ | ||
64 | #define ENABLE_WD1 0x0001 | ||
65 | #define ENABLE_WD2 0x0002 | ||
66 | #define RESET_WD1 0x0010 | ||
67 | #define RESET_WD2 0x0020 | ||
68 | #define GEN_SCI 0x0100 | ||
69 | #define GEN_NMI 0x0200 | ||
70 | #define GEN_SMI 0x0400 | ||
71 | #define GEN_RESET 0x0800 | ||
72 | |||
73 | |||
74 | /* utilities */ | ||
75 | |||
76 | #define WD1 0 | ||
77 | #define WD2 1 | ||
78 | |||
79 | #define zf_writew(port, data) { outb(port, INDEX); outw(data, DATA_W); } | ||
80 | #define zf_writeb(port, data) { outb(port, INDEX); outb(data, DATA_B); } | ||
81 | #define zf_get_ZFL_version() zf_readw(ZFL_VERSION) | ||
82 | |||
83 | |||
84 | static unsigned short zf_readw(unsigned char port) | ||
85 | { | ||
86 | outb(port, INDEX); | ||
87 | return inw(DATA_W); | ||
88 | } | ||
89 | |||
90 | |||
91 | MODULE_AUTHOR("Fernando Fuganti <fuganti@conectiva.com.br>"); | ||
92 | MODULE_DESCRIPTION("MachZ ZF-Logic Watchdog driver"); | ||
93 | MODULE_LICENSE("GPL"); | ||
94 | MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); | ||
95 | |||
96 | static int nowayout = WATCHDOG_NOWAYOUT; | ||
97 | module_param(nowayout, int, 0); | ||
98 | MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); | ||
99 | |||
100 | #define PFX "machzwd" | ||
101 | |||
102 | static struct watchdog_info zf_info = { | ||
103 | .options = WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE, | ||
104 | .firmware_version = 1, | ||
105 | .identity = "ZF-Logic watchdog", | ||
106 | }; | ||
107 | |||
108 | |||
109 | /* | ||
110 | * action refers to action taken when watchdog resets | ||
111 | * 0 = GEN_RESET | ||
112 | * 1 = GEN_SMI | ||
113 | * 2 = GEN_NMI | ||
114 | * 3 = GEN_SCI | ||
115 | * defaults to GEN_RESET (0) | ||
116 | */ | ||
117 | static int action = 0; | ||
118 | module_param(action, int, 0); | ||
119 | MODULE_PARM_DESC(action, "after watchdog resets, generate: 0 = RESET(*) 1 = SMI 2 = NMI 3 = SCI"); | ||
120 | |||
121 | static void zf_ping(unsigned long data); | ||
122 | |||
123 | static int zf_action = GEN_RESET; | ||
124 | static unsigned long zf_is_open; | ||
125 | static char zf_expect_close; | ||
126 | static spinlock_t zf_lock; | ||
127 | static spinlock_t zf_port_lock; | ||
128 | static DEFINE_TIMER(zf_timer, zf_ping, 0, 0); | ||
129 | static unsigned long next_heartbeat = 0; | ||
130 | |||
131 | |||
132 | /* timeout for user land heart beat (10 seconds) */ | ||
133 | #define ZF_USER_TIMEO (HZ*10) | ||
134 | |||
135 | /* timeout for hardware watchdog (~500ms) */ | ||
136 | #define ZF_HW_TIMEO (HZ/2) | ||
137 | |||
138 | /* number of ticks on WD#1 (driven by a 32KHz clock, 2s) */ | ||
139 | #define ZF_CTIMEOUT 0xffff | ||
140 | |||
141 | #ifndef ZF_DEBUG | ||
142 | # define dprintk(format, args...) | ||
143 | #else | ||
144 | # define dprintk(format, args...) printk(KERN_DEBUG PFX ":%s:%d: " format, __FUNCTION__, __LINE__ , ## args) | ||
145 | #endif | ||
146 | |||
147 | |||
148 | static inline void zf_set_status(unsigned char new) | ||
149 | { | ||
150 | zf_writeb(STATUS, new); | ||
151 | } | ||
152 | |||
153 | |||
154 | /* CONTROL register functions */ | ||
155 | |||
156 | static inline unsigned short zf_get_control(void) | ||
157 | { | ||
158 | return zf_readw(CONTROL); | ||
159 | } | ||
160 | |||
161 | static inline void zf_set_control(unsigned short new) | ||
162 | { | ||
163 | zf_writew(CONTROL, new); | ||
164 | } | ||
165 | |||
166 | |||
167 | /* WD#? counter functions */ | ||
168 | /* | ||
169 | * Just set counter value | ||
170 | */ | ||
171 | |||
172 | static inline void zf_set_timer(unsigned short new, unsigned char n) | ||
173 | { | ||
174 | switch(n){ | ||
175 | case WD1: | ||
176 | zf_writew(COUNTER_1, new); | ||
177 | case WD2: | ||
178 | zf_writeb(COUNTER_2, new > 0xff ? 0xff : new); | ||
179 | default: | ||
180 | return; | ||
181 | } | ||
182 | } | ||
183 | |||
184 | /* | ||
185 | * stop hardware timer | ||
186 | */ | ||
187 | static void zf_timer_off(void) | ||
188 | { | ||
189 | unsigned int ctrl_reg = 0; | ||
190 | unsigned long flags; | ||
191 | |||
192 | /* stop internal ping */ | ||
193 | del_timer_sync(&zf_timer); | ||
194 | |||
195 | spin_lock_irqsave(&zf_port_lock, flags); | ||
196 | /* stop watchdog timer */ | ||
197 | ctrl_reg = zf_get_control(); | ||
198 | ctrl_reg |= (ENABLE_WD1|ENABLE_WD2); /* disable wd1 and wd2 */ | ||
199 | ctrl_reg &= ~(ENABLE_WD1|ENABLE_WD2); | ||
200 | zf_set_control(ctrl_reg); | ||
201 | spin_unlock_irqrestore(&zf_port_lock, flags); | ||
202 | |||
203 | printk(KERN_INFO PFX ": Watchdog timer is now disabled\n"); | ||
204 | } | ||
205 | |||
206 | |||
207 | /* | ||
208 | * start hardware timer | ||
209 | */ | ||
210 | static void zf_timer_on(void) | ||
211 | { | ||
212 | unsigned int ctrl_reg = 0; | ||
213 | unsigned long flags; | ||
214 | |||
215 | spin_lock_irqsave(&zf_port_lock, flags); | ||
216 | |||
217 | zf_writeb(PULSE_LEN, 0xff); | ||
218 | |||
219 | zf_set_timer(ZF_CTIMEOUT, WD1); | ||
220 | |||
221 | /* user land ping */ | ||
222 | next_heartbeat = jiffies + ZF_USER_TIMEO; | ||
223 | |||
224 | /* start the timer for internal ping */ | ||
225 | mod_timer(&zf_timer, jiffies + ZF_HW_TIMEO); | ||
226 | |||
227 | /* start watchdog timer */ | ||
228 | ctrl_reg = zf_get_control(); | ||
229 | ctrl_reg |= (ENABLE_WD1|zf_action); | ||
230 | zf_set_control(ctrl_reg); | ||
231 | spin_unlock_irqrestore(&zf_port_lock, flags); | ||
232 | |||
233 | printk(KERN_INFO PFX ": Watchdog timer is now enabled\n"); | ||
234 | } | ||
235 | |||
236 | |||
237 | static void zf_ping(unsigned long data) | ||
238 | { | ||
239 | unsigned int ctrl_reg = 0; | ||
240 | unsigned long flags; | ||
241 | |||
242 | zf_writeb(COUNTER_2, 0xff); | ||
243 | |||
244 | if(time_before(jiffies, next_heartbeat)){ | ||
245 | |||
246 | dprintk("time_before: %ld\n", next_heartbeat - jiffies); | ||
247 | |||
248 | /* | ||
249 | * reset event is activated by transition from 0 to 1 on | ||
250 | * RESET_WD1 bit and we assume that it is already zero... | ||
251 | */ | ||
252 | |||
253 | spin_lock_irqsave(&zf_port_lock, flags); | ||
254 | ctrl_reg = zf_get_control(); | ||
255 | ctrl_reg |= RESET_WD1; | ||
256 | zf_set_control(ctrl_reg); | ||
257 | |||
258 | /* ...and nothing changes until here */ | ||
259 | ctrl_reg &= ~(RESET_WD1); | ||
260 | zf_set_control(ctrl_reg); | ||
261 | spin_unlock_irqrestore(&zf_port_lock, flags); | ||
262 | |||
263 | mod_timer(&zf_timer, jiffies + ZF_HW_TIMEO); | ||
264 | }else{ | ||
265 | printk(KERN_CRIT PFX ": I will reset your machine\n"); | ||
266 | } | ||
267 | } | ||
268 | |||
269 | static ssize_t zf_write(struct file *file, const char __user *buf, size_t count, | ||
270 | loff_t *ppos) | ||
271 | { | ||
272 | /* See if we got the magic character */ | ||
273 | if(count){ | ||
274 | |||
275 | /* | ||
276 | * no need to check for close confirmation | ||
277 | * no way to disable watchdog ;) | ||
278 | */ | ||
279 | if (!nowayout) { | ||
280 | size_t ofs; | ||
281 | |||
282 | /* | ||
283 | * note: just in case someone wrote the magic character | ||
284 | * five months ago... | ||
285 | */ | ||
286 | zf_expect_close = 0; | ||
287 | |||
288 | /* now scan */ | ||
289 | for (ofs = 0; ofs != count; ofs++){ | ||
290 | char c; | ||
291 | if (get_user(c, buf + ofs)) | ||
292 | return -EFAULT; | ||
293 | if (c == 'V'){ | ||
294 | zf_expect_close = 42; | ||
295 | dprintk("zf_expect_close = 42\n"); | ||
296 | } | ||
297 | } | ||
298 | } | ||
299 | |||
300 | /* | ||
301 | * Well, anyhow someone wrote to us, | ||
302 | * we should return that favour | ||
303 | */ | ||
304 | next_heartbeat = jiffies + ZF_USER_TIMEO; | ||
305 | dprintk("user ping at %ld\n", jiffies); | ||
306 | |||
307 | } | ||
308 | |||
309 | return count; | ||
310 | } | ||
311 | |||
312 | static int zf_ioctl(struct inode *inode, struct file *file, unsigned int cmd, | ||
313 | unsigned long arg) | ||
314 | { | ||
315 | void __user *argp = (void __user *)arg; | ||
316 | int __user *p = argp; | ||
317 | switch (cmd) { | ||
318 | case WDIOC_GETSUPPORT: | ||
319 | if (copy_to_user(argp, &zf_info, sizeof(zf_info))) | ||
320 | return -EFAULT; | ||
321 | break; | ||
322 | |||
323 | case WDIOC_GETSTATUS: | ||
324 | case WDIOC_GETBOOTSTATUS: | ||
325 | return put_user(0, p); | ||
326 | |||
327 | case WDIOC_KEEPALIVE: | ||
328 | zf_ping(0); | ||
329 | break; | ||
330 | |||
331 | default: | ||
332 | return -ENOTTY; | ||
333 | } | ||
334 | |||
335 | return 0; | ||
336 | } | ||
337 | |||
338 | static int zf_open(struct inode *inode, struct file *file) | ||
339 | { | ||
340 | spin_lock(&zf_lock); | ||
341 | if(test_and_set_bit(0, &zf_is_open)) { | ||
342 | spin_unlock(&zf_lock); | ||
343 | return -EBUSY; | ||
344 | } | ||
345 | |||
346 | if (nowayout) | ||
347 | __module_get(THIS_MODULE); | ||
348 | |||
349 | spin_unlock(&zf_lock); | ||
350 | |||
351 | zf_timer_on(); | ||
352 | |||
353 | return nonseekable_open(inode, file); | ||
354 | } | ||
355 | |||
356 | static int zf_close(struct inode *inode, struct file *file) | ||
357 | { | ||
358 | if(zf_expect_close == 42){ | ||
359 | zf_timer_off(); | ||
360 | } else { | ||
361 | del_timer(&zf_timer); | ||
362 | printk(KERN_ERR PFX ": device file closed unexpectedly. Will not stop the WDT!\n"); | ||
363 | } | ||
364 | |||
365 | spin_lock(&zf_lock); | ||
366 | clear_bit(0, &zf_is_open); | ||
367 | spin_unlock(&zf_lock); | ||
368 | |||
369 | zf_expect_close = 0; | ||
370 | |||
371 | return 0; | ||
372 | } | ||
373 | |||
374 | /* | ||
375 | * Notifier for system down | ||
376 | */ | ||
377 | |||
378 | static int zf_notify_sys(struct notifier_block *this, unsigned long code, | ||
379 | void *unused) | ||
380 | { | ||
381 | if(code == SYS_DOWN || code == SYS_HALT){ | ||
382 | zf_timer_off(); | ||
383 | } | ||
384 | |||
385 | return NOTIFY_DONE; | ||
386 | } | ||
387 | |||
388 | |||
389 | |||
390 | |||
391 | static const struct file_operations zf_fops = { | ||
392 | .owner = THIS_MODULE, | ||
393 | .llseek = no_llseek, | ||
394 | .write = zf_write, | ||
395 | .ioctl = zf_ioctl, | ||
396 | .open = zf_open, | ||
397 | .release = zf_close, | ||
398 | }; | ||
399 | |||
400 | static struct miscdevice zf_miscdev = { | ||
401 | .minor = WATCHDOG_MINOR, | ||
402 | .name = "watchdog", | ||
403 | .fops = &zf_fops, | ||
404 | }; | ||
405 | |||
406 | |||
407 | /* | ||
408 | * The device needs to learn about soft shutdowns in order to | ||
409 | * turn the timebomb registers off. | ||
410 | */ | ||
411 | static struct notifier_block zf_notifier = { | ||
412 | .notifier_call = zf_notify_sys, | ||
413 | }; | ||
414 | |||
415 | static void __init zf_show_action(int act) | ||
416 | { | ||
417 | char *str[] = { "RESET", "SMI", "NMI", "SCI" }; | ||
418 | |||
419 | printk(KERN_INFO PFX ": Watchdog using action = %s\n", str[act]); | ||
420 | } | ||
421 | |||
422 | static int __init zf_init(void) | ||
423 | { | ||
424 | int ret; | ||
425 | |||
426 | printk(KERN_INFO PFX ": MachZ ZF-Logic Watchdog driver initializing.\n"); | ||
427 | |||
428 | ret = zf_get_ZFL_version(); | ||
429 | if ((!ret) || (ret == 0xffff)) { | ||
430 | printk(KERN_WARNING PFX ": no ZF-Logic found\n"); | ||
431 | return -ENODEV; | ||
432 | } | ||
433 | |||
434 | if((action <= 3) && (action >= 0)){ | ||
435 | zf_action = zf_action>>action; | ||
436 | } else | ||
437 | action = 0; | ||
438 | |||
439 | zf_show_action(action); | ||
440 | |||
441 | spin_lock_init(&zf_lock); | ||
442 | spin_lock_init(&zf_port_lock); | ||
443 | |||
444 | if(!request_region(ZF_IOBASE, 3, "MachZ ZFL WDT")){ | ||
445 | printk(KERN_ERR "cannot reserve I/O ports at %d\n", | ||
446 | ZF_IOBASE); | ||
447 | ret = -EBUSY; | ||
448 | goto no_region; | ||
449 | } | ||
450 | |||
451 | ret = register_reboot_notifier(&zf_notifier); | ||
452 | if(ret){ | ||
453 | printk(KERN_ERR "can't register reboot notifier (err=%d)\n", | ||
454 | ret); | ||
455 | goto no_reboot; | ||
456 | } | ||
457 | |||
458 | ret = misc_register(&zf_miscdev); | ||
459 | if (ret){ | ||
460 | printk(KERN_ERR "can't misc_register on minor=%d\n", | ||
461 | WATCHDOG_MINOR); | ||
462 | goto no_misc; | ||
463 | } | ||
464 | |||
465 | zf_set_status(0); | ||
466 | zf_set_control(0); | ||
467 | |||
468 | return 0; | ||
469 | |||
470 | no_misc: | ||
471 | unregister_reboot_notifier(&zf_notifier); | ||
472 | no_reboot: | ||
473 | release_region(ZF_IOBASE, 3); | ||
474 | no_region: | ||
475 | return ret; | ||
476 | } | ||
477 | |||
478 | |||
479 | static void __exit zf_exit(void) | ||
480 | { | ||
481 | zf_timer_off(); | ||
482 | |||
483 | misc_deregister(&zf_miscdev); | ||
484 | unregister_reboot_notifier(&zf_notifier); | ||
485 | release_region(ZF_IOBASE, 3); | ||
486 | } | ||
487 | |||
488 | module_init(zf_init); | ||
489 | module_exit(zf_exit); | ||