summaryrefslogtreecommitdiffstats
path: root/drivers/char/watchdog/pcwd_pci.c
blob: 2b13afb09c5dfc4d601e65256ccf20bacc0641b2 (plain)
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
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
/*
 *	Berkshire PCI-PC Watchdog Card Driver
 *
 *	(c) Copyright 2003 Wim Van Sebroeck <wim@iguana.be>.
 *
 *	Based on source code of the following authors:
 *	  Ken Hollis <kenji@bitgate.com>,
 *	  Lindsay Harris <lindsay@bluegum.com>,
 *	  Alan Cox <alan@redhat.com>,
 *	  Matt Domsch <Matt_Domsch@dell.com>,
 *	  Rob Radez <rob@osinvestor.com>
 *
 *	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.
 *
 *	Neither Wim Van Sebroeck nor Iguana vzw. admit liability nor
 *	provide warranty for any of this software. This material is
 *	provided "AS-IS" and at no charge.
 */

/*
 *	A bells and whistles driver is available from http://www.pcwd.de/
 *	More info available at http://www.berkprod.com/ or http://www.pcwatchdog.com/
 */

/*
 *	Includes, defines, variables, module parameters, ...
 */

#include <linux/config.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/types.h>
#include <linux/delay.h>
#include <linux/miscdevice.h>
#include <linux/watchdog.h>
#include <linux/notifier.h>
#include <linux/reboot.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/pci.h>
#include <linux/ioport.h>
#include <linux/spinlock.h>

#include <asm/uaccess.h>
#include <asm/io.h>

/* Module and version information */
#define WATCHDOG_VERSION "1.01"
#define WATCHDOG_DATE "15 Mar 2005"
#define WATCHDOG_DRIVER_NAME "PCI-PC Watchdog"
#define WATCHDOG_NAME "pcwd_pci"
#define PFX WATCHDOG_NAME ": "
#define DRIVER_VERSION WATCHDOG_DRIVER_NAME " driver, v" WATCHDOG_VERSION " (" WATCHDOG_DATE ")\n"

/* Stuff for the PCI ID's  */
#ifndef PCI_VENDOR_ID_QUICKLOGIC
#define PCI_VENDOR_ID_QUICKLOGIC    0x11e3
#endif

#ifndef PCI_DEVICE_ID_WATCHDOG_PCIPCWD
#define PCI_DEVICE_ID_WATCHDOG_PCIPCWD 0x5030
#endif

/*
 * These are the defines that describe the control status bits for the
 * PCI-PC Watchdog card.
 */
#define WD_PCI_WTRP             0x01	/* Watchdog Trip status */
#define WD_PCI_HRBT             0x02	/* Watchdog Heartbeat */
#define WD_PCI_TTRP             0x04	/* Temperature Trip status */

/* according to documentation max. time to process a command for the pci
 * watchdog card is 100 ms, so we give it 150 ms to do it's job */
#define PCI_COMMAND_TIMEOUT	150

/* Watchdog's internal commands */
#define CMD_GET_STATUS			0x04
#define CMD_GET_FIRMWARE_VERSION	0x08
#define CMD_READ_WATCHDOG_TIMEOUT	0x18
#define CMD_WRITE_WATCHDOG_TIMEOUT	0x19

/* We can only use 1 card due to the /dev/watchdog restriction */
static int cards_found;

/* internal variables */
static int temp_panic;
static unsigned long is_active;
static char expect_release;
static struct {
	int supports_temp;	/* Wether or not the card has a temperature device */
	int boot_status;	/* The card's boot status */
	unsigned long io_addr;	/* The cards I/O address */
	spinlock_t io_lock;
	struct pci_dev *pdev;
} pcipcwd_private;

/* module parameters */
#define WATCHDOG_HEARTBEAT 2	/* 2 sec default heartbeat */
static int heartbeat = WATCHDOG_HEARTBEAT;
module_param(heartbeat, int, 0);
MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds. (0<heartbeat<65536, default=" __MODULE_STRING(WATCHDOG_HEARTBEAT) ")");

static int nowayout = WATCHDOG_NOWAYOUT;
module_param(nowayout, int, 0);
MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=CONFIG_WATCHDOG_NOWAYOUT)");

/*
 *	Internal functions
 */

static int send_command(int cmd, int *msb, int *lsb)
{
	int got_response, count;

	spin_lock(&pcipcwd_private.io_lock);
	/* If a command requires data it should be written first.
	 * Data for commands with 8 bits of data should be written to port 4.
	 * Commands with 16 bits of data, should be written as LSB to port 4
	 * and MSB to port 5.
	 * After the required data has been written then write the command to
	 * port 6. */
	outb_p(*lsb, pcipcwd_private.io_addr + 4);
	outb_p(*msb, pcipcwd_private.io_addr + 5);
	outb_p(cmd, pcipcwd_private.io_addr + 6);

	/* wait till the pci card processed the command, signaled by
	 * the WRSP bit in port 2 and give it a max. timeout of
	 * PCI_COMMAND_TIMEOUT to process */
	got_response = inb_p(pcipcwd_private.io_addr + 2) & 0x40;
	for (count = 0; (count < PCI_COMMAND_TIMEOUT) && (!got_response); count++) {
		mdelay(1);
		got_response = inb_p(pcipcwd_private.io_addr + 2) & 0x40;
	}

	if (got_response) {
		/* read back response */
		*lsb = inb_p(pcipcwd_private.io_addr + 4);
		*msb = inb_p(pcipcwd_private.io_addr + 5);

		/* clear WRSP bit */
		inb_p(pcipcwd_private.io_addr + 6);
	}
	spin_unlock(&pcipcwd_private.io_lock);

	return got_response;
}

static int pcipcwd_start(void)
{
	int stat_reg;

	spin_lock(&pcipcwd_private.io_lock);
	outb_p(0x00, pcipcwd_private.io_addr + 3);
	udelay(1000);

	stat_reg = inb_p(pcipcwd_private.io_addr + 2);
	spin_unlock(&pcipcwd_private.io_lock);

	if (stat_reg & 0x10) {
		printk(KERN_ERR PFX "Card timer not enabled\n");
		return -1;
	}

	return 0;
}

static int pcipcwd_stop(void)
{
	int stat_reg;

	spin_lock(&pcipcwd_private.io_lock);
	outb_p(0xA5, pcipcwd_private.io_addr + 3);
	udelay(1000);

	outb_p(0xA5, pcipcwd_private.io_addr + 3);
	udelay(1000);

	stat_reg = inb_p(pcipcwd_private.io_addr + 2);
	spin_unlock(&pcipcwd_private.io_lock);

	if (!(stat_reg & 0x10)) {
		printk(KERN_ERR PFX "Card did not acknowledge disable attempt\n");
		return -1;
	}

	return 0;
}

static int pcipcwd_keepalive(void)
{
	/* Re-trigger watchdog by writing to port 0 */
	outb_p(0x42, pcipcwd_private.io_addr);
	return 0;
}

static int pcipcwd_set_heartbeat(int t)
{
	int t_msb = t / 256;
	int t_lsb = t % 256;

	if ((t < 0x0001) || (t > 0xFFFF))
		return -EINVAL;

	/* Write new heartbeat to watchdog */
	send_command(CMD_WRITE_WATCHDOG_TIMEOUT, &t_msb, &t_lsb);

	heartbeat = t;
	return 0;
}

static int pcipcwd_get_status(int *status)
{
	int new_status;

	*status=0;
	new_status = inb_p(pcipcwd_private.io_addr + 1);
	if (new_status & WD_PCI_WTRP)
		*status |= WDIOF_CARDRESET;
	if (new_status & WD_PCI_TTRP) {
		*status |= WDIOF_OVERHEAT;
		if (temp_panic)
			panic(PFX "Temperature overheat trip!\n");
	}

	return 0;
}

static int pcipcwd_clear_status(void)
{
	outb_p(0x01, pcipcwd_private.io_addr + 1);
	return 0;
}

static int pcipcwd_get_temperature(int *temperature)
{
	*temperature = 0;
	if (!pcipcwd_private.supports_temp)
		return -ENODEV;

	/*
	 * Convert celsius to fahrenheit, since this was
	 * the decided 'standard' for this return value.
	 */
	*temperature = ((inb_p(pcipcwd_private.io_addr)) * 9 / 5) + 32;

	return 0;
}

/*
 *	/dev/watchdog handling
 */

static ssize_t pcipcwd_write(struct file *file, const char __user *data,
			      size_t len, loff_t *ppos)
{
	/* See if we got the magic character 'V' and reload the timer */
	if (len) {
		if (!nowayout) {
			size_t i;

			/* note: just in case someone wrote the magic character
			 * five months ago... */
			expect_release = 0;

			/* scan to see whether or not we got the magic character */
			for (i = 0; i != len; i++) {
				char c;
				if(get_user(c, data+i))
					return -EFAULT;
				if (c == 'V')
					expect_release = 42;
			}
		}

		/* someone wrote to us, we should reload the timer */
		pcipcwd_keepalive();
	}
	return len;
}

static int pcipcwd_ioctl(struct inode *inode, struct file *file,
			  unsigned int cmd, unsigned long arg)
{
	void __user *argp = (void __user *)arg;
	int __user *p = argp;
	static struct watchdog_info ident = {
		.options =		WDIOF_OVERHEAT |
					WDIOF_CARDRESET |
					WDIOF_KEEPALIVEPING |
					WDIOF_SETTIMEOUT |
					WDIOF_MAGICCLOSE,
		.firmware_version =	1,
		.identity =		WATCHDOG_DRIVER_NAME,
	};

	switch (cmd) {
		case WDIOC_GETSUPPORT:
			return copy_to_user(argp, &ident,
				sizeof (ident)) ? -EFAULT : 0;

		case WDIOC_GETSTATUS:
		{
			int status;

			pcipcwd_get_status(&status);

			return put_user(status, p);
		}

		case WDIOC_GETBOOTSTATUS:
			return put_user(pcipcwd_private.boot_status, p);

		case WDIOC_GETTEMP:
		{
			int temperature;

			if (pcipcwd_get_temperature(&temperature))
				return -EFAULT;

			return put_user(temperature, p);
		}

		case WDIOC_KEEPALIVE:
			pcipcwd_keepalive();
			return 0;

		case WDIOC_SETOPTIONS:
		{
			int new_options, retval = -EINVAL;

			if (get_user (new_options, p))
				return -EFAULT;

			if (new_options & WDIOS_DISABLECARD) {
				pcipcwd_stop();
				retval = 0;
			}

			if (new_options & WDIOS_ENABLECARD) {
				pcipcwd_start();
				retval = 0;
			}

			if (new_options & WDIOS_TEMPPANIC) {
				temp_panic = 1;
				retval = 0;
			}

			return retval;
		}

		case WDIOC_SETTIMEOUT:
		{
			int new_heartbeat;

			if (get_user(new_heartbeat, p))
				return -EFAULT;

			if (pcipcwd_set_heartbeat(new_heartbeat))
			    return -EINVAL;

			pcipcwd_keepalive();
			/* Fall */
		}

		case WDIOC_GETTIMEOUT:
			return put_user(heartbeat, p);

		default:
			return -ENOIOCTLCMD;
	}
}

static int pcipcwd_open(struct inode *inode, struct file *file)
{
	/* /dev/watchdog can only be opened once */
	if (test_and_set_bit(0, &is_active))
		return -EBUSY;

	/* Activate */
	pcipcwd_start();
	pcipcwd_keepalive();
	return nonseekable_open(inode, file);
}

static int pcipcwd_release(struct inode *inode, struct file *file)
{
	/*
	 *      Shut off the timer.
	 */
	if (expect_release == 42) {
		pcipcwd_stop();
	} else {
		printk(KERN_CRIT PFX "Unexpected close, not stopping watchdog!\n");
		pcipcwd_keepalive();
	}
	expect_release = 0;
	clear_bit(0, &is_active);
	return 0;
}

/*
 *	/dev/temperature handling
 */

static ssize_t pcipcwd_temp_read(struct file *file, char __user *data,
				size_t len, loff_t *ppos)
{
	int temperature;

	if (pcipcwd_get_temperature(&temperature))
		return -EFAULT;

	if (copy_to_user (data, &temperature, 1))
		return -EFAULT;

	return 1;
}

static int pcipcwd_temp_open(struct inode *inode, struct file *file)
{
	if (!pcipcwd_private.supports_temp)
		return -ENODEV;

	return nonseekable_open(inode, file);
}

static int pcipcwd_temp_release(struct inode *inode, struct file *file)
{
	return 0;
}

/*
 *	Notify system
 */

static int pcipcwd_notify_sys(struct notifier_block *this, unsigned long code, void *unused)
{
	if (code==SYS_DOWN || code==SYS_HALT) {
		/* Turn the WDT off */
		pcipcwd_stop();
	}

	return NOTIFY_DONE;
}

/*
 *	Kernel Interfaces
 */

static struct file_operations pcipcwd_fops = {
	.owner =	THIS_MODULE,
	.llseek =	no_llseek,
	.write =	pcipcwd_write,
	.ioctl =	pcipcwd_ioctl,
	.open =		pcipcwd_open,
	.release =	pcipcwd_release,
};

static struct miscdevice pcipcwd_miscdev = {
	.minor =	WATCHDOG_MINOR,
	.name =		"watchdog",
	.fops =		&pcipcwd_fops,
};

static struct file_operations pcipcwd_temp_fops = {
	.owner =	THIS_MODULE,
	.llseek =	no_llseek,
	.read =		pcipcwd_temp_read,
	.open =		pcipcwd_temp_open,
	.release =	pcipcwd_temp_release,
};

static struct miscdevice pcipcwd_temp_miscdev = {
	.minor =	TEMP_MINOR,
	.name =		"temperature",
	.fops =		&pcipcwd_temp_fops,
};

static struct notifier_block pcipcwd_notifier = {
	.notifier_call =	pcipcwd_notify_sys,
};

/*
 *	Init & exit routines
 */

static inline void check_temperature_support(void)
{
	if (inb_p(pcipcwd_private.io_addr) != 0xF0)
		pcipcwd_private.supports_temp = 1;
}

static int __devinit pcipcwd_card_init(struct pci_dev *pdev,
		const struct pci_device_id *ent)
{
	int ret = -EIO;
	int got_fw_rev, fw_rev_major, fw_rev_minor;
	char fw_ver_str[20];
	char option_switches;

	cards_found++;
	if (cards_found == 1)
		printk(KERN_INFO PFX DRIVER_VERSION);

	if (cards_found > 1) {
		printk(KERN_ERR PFX "This driver only supports 1 device\n");
		return -ENODEV;
	}

	if (pci_enable_device(pdev)) {
		printk(KERN_ERR PFX "Not possible to enable PCI Device\n");
		return -ENODEV;
	}

	if (pci_resource_start(pdev, 0) == 0x0000) {
		printk(KERN_ERR PFX "No I/O-Address for card detected\n");
		ret = -ENODEV;
		goto err_out_disable_device;
	}

	pcipcwd_private.pdev = pdev;
	pcipcwd_private.io_addr = pci_resource_start(pdev, 0);

	if (pci_request_regions(pdev, WATCHDOG_NAME)) {
		printk(KERN_ERR PFX "I/O address 0x%04x already in use\n",
			(int) pcipcwd_private.io_addr);
		ret = -EIO;
		goto err_out_disable_device;
	}

	/* get the boot_status */
	pcipcwd_get_status(&pcipcwd_private.boot_status);

	/* clear the "card caused reboot" flag */
	pcipcwd_clear_status();

	/* disable card */
	pcipcwd_stop();

	/* Check whether or not the card supports the temperature device */
	check_temperature_support();

	/* Get the Firmware Version */
	got_fw_rev = send_command(CMD_GET_FIRMWARE_VERSION, &fw_rev_major, &fw_rev_minor);
	if (got_fw_rev) {
		sprintf(fw_ver_str, "%u.%02u", fw_rev_major, fw_rev_minor);
	} else {
		sprintf(fw_ver_str, "<card no answer>");
	}

	/* Get switch settings */
	option_switches = inb_p(pcipcwd_private.io_addr + 3);

	printk(KERN_INFO PFX "Found card at port 0x%04x (Firmware: %s) %s temp option\n",
		(int) pcipcwd_private.io_addr, fw_ver_str,
		(pcipcwd_private.supports_temp ? "with" : "without"));

	printk(KERN_INFO PFX "Option switches (0x%02x): Temperature Reset Enable=%s, Power On Delay=%s\n",
		option_switches,
		((option_switches & 0x10) ? "ON" : "OFF"),
		((option_switches & 0x08) ? "ON" : "OFF"));

	if (pcipcwd_private.boot_status & WDIOF_CARDRESET)
		printk(KERN_INFO PFX "Previous reset was caused by the Watchdog card\n");

	if (pcipcwd_private.boot_status & WDIOF_OVERHEAT)
		printk(KERN_INFO PFX "Card sensed a CPU Overheat\n");

	if (pcipcwd_private.boot_status == 0)
		printk(KERN_INFO PFX "No previous trip detected - Cold boot or reset\n");

	/* Check that the heartbeat value is within it's range ; if not reset to the default */
	if (pcipcwd_set_heartbeat(heartbeat)) {
		pcipcwd_set_heartbeat(WATCHDOG_HEARTBEAT);
		printk(KERN_INFO PFX "heartbeat value must be 0<heartbeat<65536, using %d\n",
			WATCHDOG_HEARTBEAT);
	}

	ret = register_reboot_notifier(&pcipcwd_notifier);
	if (ret != 0) {
		printk(KERN_ERR PFX "cannot register reboot notifier (err=%d)\n",
			ret);
		goto err_out_release_region;
	}

	if (pcipcwd_private.supports_temp) {
		ret = misc_register(&pcipcwd_temp_miscdev);
		if (ret != 0) {
			printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
				TEMP_MINOR, ret);
			goto err_out_unregister_reboot;
		}
	}

	ret = misc_register(&pcipcwd_miscdev);
	if (ret != 0) {
		printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
			WATCHDOG_MINOR, ret);
		goto err_out_misc_deregister;
	}

	printk(KERN_INFO PFX "initialized. heartbeat=%d sec (nowayout=%d)\n",
		heartbeat, nowayout);

	return 0;

err_out_misc_deregister:
	if (pcipcwd_private.supports_temp)
		misc_deregister(&pcipcwd_temp_miscdev);
err_out_unregister_reboot:
	unregister_reboot_notifier(&pcipcwd_notifier);
err_out_release_region:
	pci_release_regions(pdev);
err_out_disable_device:
	pci_disable_device(pdev);
	return ret;
}

static void __devexit pcipcwd_card_exit(struct pci_dev *pdev)
{
	/* Stop the timer before we leave */
	if (!nowayout)
		pcipcwd_stop();

	/* Deregister */
	misc_deregister(&pcipcwd_miscdev);
	if (pcipcwd_private.supports_temp)
		misc_deregister(&pcipcwd_temp_miscdev);
	unregister_reboot_notifier(&pcipcwd_notifier);
	pci_release_regions(pdev);
	pci_disable_device(pdev);
	cards_found--;
}

static struct pci_device_id pcipcwd_pci_tbl[] = {
	{ PCI_VENDOR_ID_QUICKLOGIC, PCI_DEVICE_ID_WATCHDOG_PCIPCWD,
		PCI_ANY_ID, PCI_ANY_ID, },
	{ 0 },			/* End of list */
};
MODULE_DEVICE_TABLE(pci, pcipcwd_pci_tbl);

static struct pci_driver pcipcwd_driver = {
	.name		= WATCHDOG_NAME,
	.id_table	= pcipcwd_pci_tbl,
	.probe		= pcipcwd_card_init,
	.remove		= __devexit_p(pcipcwd_card_exit),
};

static int __init pcipcwd_init_module(void)
{
	spin_lock_init (&pcipcwd_private.io_lock);

	return pci_register_driver(&pcipcwd_driver);
}

static void __exit pcipcwd_cleanup_module(void)
{
	pci_unregister_driver(&pcipcwd_driver);
}

module_init(pcipcwd_init_module);
module_exit(pcipcwd_cleanup_module);

MODULE_AUTHOR("Wim Van Sebroeck <wim@iguana.be>");
MODULE_DESCRIPTION("Berkshire PCI-PC Watchdog driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
MODULE_ALIAS_MISCDEV(TEMP_MINOR);