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v3.1
  1/*
  2 *	i6300esb:	Watchdog timer driver for Intel 6300ESB chipset
  3 *
  4 *	(c) Copyright 2004 Google Inc.
  5 *	(c) Copyright 2005 David Härdeman <david@2gen.com>
  6 *
  7 *	This program is free software; you can redistribute it and/or
  8 *	modify it under the terms of the GNU General Public License
  9 *	as published by the Free Software Foundation; either version
 10 *	2 of the License, or (at your option) any later version.
 11 *
 12 *	based on i810-tco.c which is in turn based on softdog.c
 13 *
 14 *	The timer is implemented in the following I/O controller hubs:
 15 *	(See the intel documentation on http://developer.intel.com.)
 16 *	6300ESB chip : document number 300641-004
 17 *
 18 *  2004YYZZ Ross Biro
 19 *	Initial version 0.01
 20 *  2004YYZZ Ross Biro
 21 *	Version 0.02
 22 *  20050210 David Härdeman <david@2gen.com>
 23 *	Ported driver to kernel 2.6
 
 
 
 24 */
 25
 26/*
 27 *      Includes, defines, variables, module parameters, ...
 28 */
 29
 30#include <linux/module.h>
 31#include <linux/types.h>
 32#include <linux/kernel.h>
 33#include <linux/fs.h>
 34#include <linux/mm.h>
 35#include <linux/miscdevice.h>
 36#include <linux/watchdog.h>
 37#include <linux/init.h>
 38#include <linux/pci.h>
 39#include <linux/ioport.h>
 40#include <linux/uaccess.h>
 41#include <linux/io.h>
 42
 43/* Module and version information */
 44#define ESB_VERSION "0.05"
 45#define ESB_MODULE_NAME "i6300ESB timer"
 46#define ESB_DRIVER_NAME ESB_MODULE_NAME ", v" ESB_VERSION
 47#define PFX ESB_MODULE_NAME ": "
 48
 49/* PCI configuration registers */
 50#define ESB_CONFIG_REG  0x60            /* Config register                   */
 51#define ESB_LOCK_REG    0x68            /* WDT lock register                 */
 52
 53/* Memory mapped registers */
 54#define ESB_TIMER1_REG (BASEADDR + 0x00)/* Timer1 value after each reset     */
 55#define ESB_TIMER2_REG (BASEADDR + 0x04)/* Timer2 value after each reset     */
 56#define ESB_GINTSR_REG (BASEADDR + 0x08)/* General Interrupt Status Register */
 57#define ESB_RELOAD_REG (BASEADDR + 0x0c)/* Reload register                   */
 58
 59/* Lock register bits */
 60#define ESB_WDT_FUNC    (0x01 << 2)   /* Watchdog functionality            */
 61#define ESB_WDT_ENABLE  (0x01 << 1)   /* Enable WDT                        */
 62#define ESB_WDT_LOCK    (0x01 << 0)   /* Lock (nowayout)                   */
 63
 64/* Config register bits */
 65#define ESB_WDT_REBOOT  (0x01 << 5)   /* Enable reboot on timeout          */
 66#define ESB_WDT_FREQ    (0x01 << 2)   /* Decrement frequency               */
 67#define ESB_WDT_INTTYPE (0x03 << 0)   /* Interrupt type on timer1 timeout  */
 68
 69/* Reload register bits */
 70#define ESB_WDT_TIMEOUT (0x01 << 9)    /* Watchdog timed out                */
 71#define ESB_WDT_RELOAD  (0x01 << 8)    /* prevent timeout                   */
 72
 73/* Magic constants */
 74#define ESB_UNLOCK1     0x80            /* Step 1 to unlock reset registers  */
 75#define ESB_UNLOCK2     0x86            /* Step 2 to unlock reset registers  */
 76
 77/* internal variables */
 78static void __iomem *BASEADDR;
 79static DEFINE_SPINLOCK(esb_lock); /* Guards the hardware */
 80static unsigned long timer_alive;
 81static struct pci_dev *esb_pci;
 82static unsigned short triggered; /* The status of the watchdog upon boot */
 83static char esb_expect_close;
 84
 85/* We can only use 1 card due to the /dev/watchdog restriction */
 86static int cards_found;
 87
 88/* module parameters */
 89/* 30 sec default heartbeat (1 < heartbeat < 2*1023) */
 90#define WATCHDOG_HEARTBEAT 30
 91static int heartbeat = WATCHDOG_HEARTBEAT;  /* in seconds */
 
 
 
 
 92module_param(heartbeat, int, 0);
 93MODULE_PARM_DESC(heartbeat,
 94		"Watchdog heartbeat in seconds. (1<heartbeat<2046, default="
 95				__MODULE_STRING(WATCHDOG_HEARTBEAT) ")");
 96
 97static int nowayout = WATCHDOG_NOWAYOUT;
 98module_param(nowayout, int, 0);
 99MODULE_PARM_DESC(nowayout,
100		"Watchdog cannot be stopped once started (default="
101				__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
102
 
 
 
 
 
 
 
 
 
103/*
104 * Some i6300ESB specific functions
105 */
106
107/*
108 * Prepare for reloading the timer by unlocking the proper registers.
109 * This is performed by first writing 0x80 followed by 0x86 to the
110 * reload register. After this the appropriate registers can be written
111 * to once before they need to be unlocked again.
112 */
113static inline void esb_unlock_registers(void)
114{
115	writew(ESB_UNLOCK1, ESB_RELOAD_REG);
116	writew(ESB_UNLOCK2, ESB_RELOAD_REG);
117}
118
119static int esb_timer_start(void)
120{
 
 
121	u8 val;
122
123	spin_lock(&esb_lock);
124	esb_unlock_registers();
125	writew(ESB_WDT_RELOAD, ESB_RELOAD_REG);
126	/* Enable or Enable + Lock? */
127	val = ESB_WDT_ENABLE | (nowayout ? ESB_WDT_LOCK : 0x00);
128	pci_write_config_byte(esb_pci, ESB_LOCK_REG, val);
129	spin_unlock(&esb_lock);
130	return 0;
131}
132
133static int esb_timer_stop(void)
134{
 
135	u8 val;
136
137	spin_lock(&esb_lock);
138	/* First, reset timers as suggested by the docs */
139	esb_unlock_registers();
140	writew(ESB_WDT_RELOAD, ESB_RELOAD_REG);
141	/* Then disable the WDT */
142	pci_write_config_byte(esb_pci, ESB_LOCK_REG, 0x0);
143	pci_read_config_byte(esb_pci, ESB_LOCK_REG, &val);
144	spin_unlock(&esb_lock);
145
146	/* Returns 0 if the timer was disabled, non-zero otherwise */
147	return val & ESB_WDT_ENABLE;
148}
149
150static void esb_timer_keepalive(void)
151{
152	spin_lock(&esb_lock);
153	esb_unlock_registers();
154	writew(ESB_WDT_RELOAD, ESB_RELOAD_REG);
 
155	/* FIXME: Do we need to flush anything here? */
156	spin_unlock(&esb_lock);
157}
158
159static int esb_timer_set_heartbeat(int time)
 
160{
 
161	u32 val;
162
163	if (time < 0x1 || time > (2 * 0x03ff))
164		return -EINVAL;
165
166	spin_lock(&esb_lock);
167
168	/* We shift by 9, so if we are passed a value of 1 sec,
169	 * val will be 1 << 9 = 512, then write that to two
170	 * timers => 2 * 512 = 1024 (which is decremented at 1KHz)
171	 */
172	val = time << 9;
173
174	/* Write timer 1 */
175	esb_unlock_registers();
176	writel(val, ESB_TIMER1_REG);
177
178	/* Write timer 2 */
179	esb_unlock_registers();
180	writel(val, ESB_TIMER2_REG);
181
182	/* Reload */
183	esb_unlock_registers();
184	writew(ESB_WDT_RELOAD, ESB_RELOAD_REG);
185
186	/* FIXME: Do we need to flush everything out? */
187
188	/* Done */
189	heartbeat = time;
190	spin_unlock(&esb_lock);
191	return 0;
192}
193
194/*
195 *	/dev/watchdog handling
196 */
197
198static int esb_open(struct inode *inode, struct file *file)
199{
200	/* /dev/watchdog can only be opened once */
201	if (test_and_set_bit(0, &timer_alive))
202		return -EBUSY;
203
204	/* Reload and activate timer */
205	esb_timer_start();
206
207	return nonseekable_open(inode, file);
208}
209
210static int esb_release(struct inode *inode, struct file *file)
211{
212	/* Shut off the timer. */
213	if (esb_expect_close == 42)
214		esb_timer_stop();
215	else {
216		printk(KERN_CRIT PFX
217				"Unexpected close, not stopping watchdog!\n");
218		esb_timer_keepalive();
219	}
220	clear_bit(0, &timer_alive);
221	esb_expect_close = 0;
222	return 0;
223}
224
225static ssize_t esb_write(struct file *file, const char __user *data,
226			  size_t len, loff_t *ppos)
227{
228	/* See if we got the magic character 'V' and reload the timer */
229	if (len) {
230		if (!nowayout) {
231			size_t i;
232
233			/* note: just in case someone wrote the magic character
234			 * five months ago... */
235			esb_expect_close = 0;
236
237			/* scan to see whether or not we got the
238			 * magic character */
239			for (i = 0; i != len; i++) {
240				char c;
241				if (get_user(c, data + i))
242					return -EFAULT;
243				if (c == 'V')
244					esb_expect_close = 42;
245			}
246		}
247
248		/* someone wrote to us, we should reload the timer */
249		esb_timer_keepalive();
250	}
251	return len;
252}
253
254static long esb_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
255{
256	int new_options, retval = -EINVAL;
257	int new_heartbeat;
258	void __user *argp = (void __user *)arg;
259	int __user *p = argp;
260	static const struct watchdog_info ident = {
261		.options =		WDIOF_SETTIMEOUT |
262					WDIOF_KEEPALIVEPING |
263					WDIOF_MAGICCLOSE,
264		.firmware_version =	0,
265		.identity =		ESB_MODULE_NAME,
266	};
267
268	switch (cmd) {
269	case WDIOC_GETSUPPORT:
270		return copy_to_user(argp, &ident,
271					sizeof(ident)) ? -EFAULT : 0;
272
273	case WDIOC_GETSTATUS:
274		return put_user(0, p);
275
276	case WDIOC_GETBOOTSTATUS:
277		return put_user(triggered, p);
278
279	case WDIOC_SETOPTIONS:
280	{
281		if (get_user(new_options, p))
282			return -EFAULT;
283
284		if (new_options & WDIOS_DISABLECARD) {
285			esb_timer_stop();
286			retval = 0;
287		}
288
289		if (new_options & WDIOS_ENABLECARD) {
290			esb_timer_start();
291			retval = 0;
292		}
293		return retval;
294	}
295	case WDIOC_KEEPALIVE:
296		esb_timer_keepalive();
297		return 0;
298
299	case WDIOC_SETTIMEOUT:
300	{
301		if (get_user(new_heartbeat, p))
302			return -EFAULT;
303		if (esb_timer_set_heartbeat(new_heartbeat))
304			return -EINVAL;
305		esb_timer_keepalive();
306		/* Fall */
307	}
308	case WDIOC_GETTIMEOUT:
309		return put_user(heartbeat, p);
310	default:
311		return -ENOTTY;
312	}
313}
314
315/*
316 *      Kernel Interfaces
317 */
318
319static const struct file_operations esb_fops = {
320	.owner = THIS_MODULE,
321	.llseek = no_llseek,
322	.write = esb_write,
323	.unlocked_ioctl = esb_ioctl,
324	.open = esb_open,
325	.release = esb_release,
326};
327
328static struct miscdevice esb_miscdev = {
329	.minor = WATCHDOG_MINOR,
330	.name = "watchdog",
331	.fops = &esb_fops,
 
 
332};
333
334/*
335 * Data for PCI driver interface
336 */
337static DEFINE_PCI_DEVICE_TABLE(esb_pci_tbl) = {
338	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ESB_9), },
339	{ 0, },                 /* End of list */
340};
341MODULE_DEVICE_TABLE(pci, esb_pci_tbl);
342
343/*
344 *      Init & exit routines
345 */
346
347static unsigned char __devinit esb_getdevice(struct pci_dev *pdev)
348{
349	if (pci_enable_device(pdev)) {
350		printk(KERN_ERR PFX "failed to enable device\n");
351		goto err_devput;
352	}
353
354	if (pci_request_region(pdev, 0, ESB_MODULE_NAME)) {
355		printk(KERN_ERR PFX "failed to request region\n");
356		goto err_disable;
357	}
358
359	BASEADDR = pci_ioremap_bar(pdev, 0);
360	if (BASEADDR == NULL) {
361		/* Something's wrong here, BASEADDR has to be set */
362		printk(KERN_ERR PFX "failed to get BASEADDR\n");
363		goto err_release;
364	}
365
366	/* Done */
367	esb_pci = pdev;
368	return 1;
369
370err_release:
371	pci_release_region(pdev, 0);
372err_disable:
373	pci_disable_device(pdev);
374err_devput:
375	return 0;
376}
377
378static void __devinit esb_initdevice(void)
379{
380	u8 val1;
381	u16 val2;
382
383	/*
384	 * Config register:
385	 * Bit    5 : 0 = Enable WDT_OUTPUT
386	 * Bit    2 : 0 = set the timer frequency to the PCI clock
387	 * divided by 2^15 (approx 1KHz).
388	 * Bits 1:0 : 11 = WDT_INT_TYPE Disabled.
389	 * The watchdog has two timers, it can be setup so that the
390	 * expiry of timer1 results in an interrupt and the expiry of
391	 * timer2 results in a reboot. We set it to not generate
392	 * any interrupts as there is not much we can do with it
393	 * right now.
394	 */
395	pci_write_config_word(esb_pci, ESB_CONFIG_REG, 0x0003);
396
397	/* Check that the WDT isn't already locked */
398	pci_read_config_byte(esb_pci, ESB_LOCK_REG, &val1);
399	if (val1 & ESB_WDT_LOCK)
400		printk(KERN_WARNING PFX "nowayout already set\n");
401
402	/* Set the timer to watchdog mode and disable it for now */
403	pci_write_config_byte(esb_pci, ESB_LOCK_REG, 0x00);
404
405	/* Check if the watchdog was previously triggered */
406	esb_unlock_registers();
407	val2 = readw(ESB_RELOAD_REG);
408	if (val2 & ESB_WDT_TIMEOUT)
409		triggered = WDIOF_CARDRESET;
410
411	/* Reset WDT_TIMEOUT flag and timers */
412	esb_unlock_registers();
413	writew((ESB_WDT_TIMEOUT | ESB_WDT_RELOAD), ESB_RELOAD_REG);
414
415	/* And set the correct timeout value */
416	esb_timer_set_heartbeat(heartbeat);
417}
418
419static int __devinit esb_probe(struct pci_dev *pdev,
420		const struct pci_device_id *ent)
421{
 
422	int ret;
423
424	cards_found++;
425	if (cards_found == 1)
426		printk(KERN_INFO PFX "Intel 6300ESB WatchDog Timer Driver v%s\n",
427			ESB_VERSION);
428
429	if (cards_found > 1) {
430		printk(KERN_ERR PFX "This driver only supports 1 device\n");
431		return -ENODEV;
432	}
433
434	/* Check whether or not the hardware watchdog is there */
435	if (!esb_getdevice(pdev) || esb_pci == NULL)
 
436		return -ENODEV;
437
438	/* Check that the heartbeat value is within it's range;
439	   if not reset to the default */
440	if (heartbeat < 0x1 || heartbeat > 2 * 0x03ff) {
441		heartbeat = WATCHDOG_HEARTBEAT;
442		printk(KERN_INFO PFX
443			"heartbeat value must be 1<heartbeat<2046, using %d\n",
444								heartbeat);
445	}
446
447	/* Initialize the watchdog and make sure it does not run */
448	esb_initdevice();
 
 
 
 
 
 
 
 
 
 
 
 
449
450	/* Register the watchdog so that userspace has access to it */
451	ret = misc_register(&esb_miscdev);
452	if (ret != 0) {
453		printk(KERN_ERR PFX
454			"cannot register miscdev on minor=%d (err=%d)\n",
455							WATCHDOG_MINOR, ret);
456		goto err_unmap;
457	}
458	printk(KERN_INFO PFX
459		"initialized (0x%p). heartbeat=%d sec (nowayout=%d)\n",
460						BASEADDR, heartbeat, nowayout);
461	return 0;
462
463err_unmap:
464	iounmap(BASEADDR);
465	pci_release_region(esb_pci, 0);
466	pci_disable_device(esb_pci);
467	esb_pci = NULL;
468	return ret;
469}
470
471static void __devexit esb_remove(struct pci_dev *pdev)
472{
473	/* Stop the timer before we leave */
474	if (!nowayout)
475		esb_timer_stop();
476
477	/* Deregister */
478	misc_deregister(&esb_miscdev);
479	iounmap(BASEADDR);
480	pci_release_region(esb_pci, 0);
481	pci_disable_device(esb_pci);
482	esb_pci = NULL;
483}
484
485static void esb_shutdown(struct pci_dev *pdev)
486{
487	esb_timer_stop();
 
488}
489
490static struct pci_driver esb_driver = {
491	.name		= ESB_MODULE_NAME,
492	.id_table	= esb_pci_tbl,
493	.probe          = esb_probe,
494	.remove         = __devexit_p(esb_remove),
495	.shutdown       = esb_shutdown,
496};
497
498static int __init watchdog_init(void)
499{
500	return pci_register_driver(&esb_driver);
501}
502
503static void __exit watchdog_cleanup(void)
504{
505	pci_unregister_driver(&esb_driver);
506	printk(KERN_INFO PFX "Watchdog Module Unloaded.\n");
507}
508
509module_init(watchdog_init);
510module_exit(watchdog_cleanup);
511
512MODULE_AUTHOR("Ross Biro and David Härdeman");
513MODULE_DESCRIPTION("Watchdog driver for Intel 6300ESB chipsets");
514MODULE_LICENSE("GPL");
515MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
v4.17
  1/*
  2 *	i6300esb:	Watchdog timer driver for Intel 6300ESB chipset
  3 *
  4 *	(c) Copyright 2004 Google Inc.
  5 *	(c) Copyright 2005 David Härdeman <david@2gen.com>
  6 *
  7 *	This program is free software; you can redistribute it and/or
  8 *	modify it under the terms of the GNU General Public License
  9 *	as published by the Free Software Foundation; either version
 10 *	2 of the License, or (at your option) any later version.
 11 *
 12 *	based on i810-tco.c which is in turn based on softdog.c
 13 *
 14 *	The timer is implemented in the following I/O controller hubs:
 15 *	(See the intel documentation on http://developer.intel.com.)
 16 *	6300ESB chip : document number 300641-004
 17 *
 18 *  2004YYZZ Ross Biro
 19 *	Initial version 0.01
 20 *  2004YYZZ Ross Biro
 21 *	Version 0.02
 22 *  20050210 David Härdeman <david@2gen.com>
 23 *	Ported driver to kernel 2.6
 24 *  20171016 Radu Rendec <rrendec@arista.com>
 25 *	Change driver to use the watchdog subsystem
 26 *	Add support for multiple 6300ESB devices
 27 */
 28
 29/*
 30 *      Includes, defines, variables, module parameters, ...
 31 */
 32
 33#include <linux/module.h>
 34#include <linux/types.h>
 35#include <linux/kernel.h>
 36#include <linux/fs.h>
 37#include <linux/mm.h>
 38#include <linux/miscdevice.h>
 39#include <linux/watchdog.h>
 
 40#include <linux/pci.h>
 41#include <linux/ioport.h>
 42#include <linux/uaccess.h>
 43#include <linux/io.h>
 44
 45/* Module and version information */
 
 46#define ESB_MODULE_NAME "i6300ESB timer"
 
 
 47
 48/* PCI configuration registers */
 49#define ESB_CONFIG_REG  0x60            /* Config register                   */
 50#define ESB_LOCK_REG    0x68            /* WDT lock register                 */
 51
 52/* Memory mapped registers */
 53#define ESB_TIMER1_REG(w) ((w)->base + 0x00)/* Timer1 value after each reset */
 54#define ESB_TIMER2_REG(w) ((w)->base + 0x04)/* Timer2 value after each reset */
 55#define ESB_GINTSR_REG(w) ((w)->base + 0x08)/* General Interrupt Status Reg  */
 56#define ESB_RELOAD_REG(w) ((w)->base + 0x0c)/* Reload register               */
 57
 58/* Lock register bits */
 59#define ESB_WDT_FUNC    (0x01 << 2)   /* Watchdog functionality            */
 60#define ESB_WDT_ENABLE  (0x01 << 1)   /* Enable WDT                        */
 61#define ESB_WDT_LOCK    (0x01 << 0)   /* Lock (nowayout)                   */
 62
 63/* Config register bits */
 64#define ESB_WDT_REBOOT  (0x01 << 5)   /* Enable reboot on timeout          */
 65#define ESB_WDT_FREQ    (0x01 << 2)   /* Decrement frequency               */
 66#define ESB_WDT_INTTYPE (0x03 << 0)   /* Interrupt type on timer1 timeout  */
 67
 68/* Reload register bits */
 69#define ESB_WDT_TIMEOUT (0x01 << 9)    /* Watchdog timed out                */
 70#define ESB_WDT_RELOAD  (0x01 << 8)    /* prevent timeout                   */
 71
 72/* Magic constants */
 73#define ESB_UNLOCK1     0x80            /* Step 1 to unlock reset registers  */
 74#define ESB_UNLOCK2     0x86            /* Step 2 to unlock reset registers  */
 75
 
 
 
 
 
 
 
 
 
 
 
 76/* module parameters */
 77/* 30 sec default heartbeat (1 < heartbeat < 2*1023) */
 78#define ESB_HEARTBEAT_MIN	1
 79#define ESB_HEARTBEAT_MAX	2046
 80#define ESB_HEARTBEAT_DEFAULT	30
 81#define ESB_HEARTBEAT_RANGE __MODULE_STRING(ESB_HEARTBEAT_MIN) \
 82	"<heartbeat<" __MODULE_STRING(ESB_HEARTBEAT_MAX)
 83static int heartbeat; /* in seconds */
 84module_param(heartbeat, int, 0);
 85MODULE_PARM_DESC(heartbeat,
 86	"Watchdog heartbeat in seconds. (" ESB_HEARTBEAT_RANGE
 87	", default=" __MODULE_STRING(ESB_HEARTBEAT_DEFAULT) ")");
 88
 89static bool nowayout = WATCHDOG_NOWAYOUT;
 90module_param(nowayout, bool, 0);
 91MODULE_PARM_DESC(nowayout,
 92		"Watchdog cannot be stopped once started (default="
 93				__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
 94
 95/* internal variables */
 96struct esb_dev {
 97	struct watchdog_device wdd;
 98	void __iomem *base;
 99	struct pci_dev *pdev;
100};
101
102#define to_esb_dev(wptr) container_of(wptr, struct esb_dev, wdd)
103
104/*
105 * Some i6300ESB specific functions
106 */
107
108/*
109 * Prepare for reloading the timer by unlocking the proper registers.
110 * This is performed by first writing 0x80 followed by 0x86 to the
111 * reload register. After this the appropriate registers can be written
112 * to once before they need to be unlocked again.
113 */
114static inline void esb_unlock_registers(struct esb_dev *edev)
115{
116	writew(ESB_UNLOCK1, ESB_RELOAD_REG(edev));
117	writew(ESB_UNLOCK2, ESB_RELOAD_REG(edev));
118}
119
120static int esb_timer_start(struct watchdog_device *wdd)
121{
122	struct esb_dev *edev = to_esb_dev(wdd);
123	int _wdd_nowayout = test_bit(WDOG_NO_WAY_OUT, &wdd->status);
124	u8 val;
125
126	esb_unlock_registers(edev);
127	writew(ESB_WDT_RELOAD, ESB_RELOAD_REG(edev));
 
128	/* Enable or Enable + Lock? */
129	val = ESB_WDT_ENABLE | (_wdd_nowayout ? ESB_WDT_LOCK : 0x00);
130	pci_write_config_byte(edev->pdev, ESB_LOCK_REG, val);
 
131	return 0;
132}
133
134static int esb_timer_stop(struct watchdog_device *wdd)
135{
136	struct esb_dev *edev = to_esb_dev(wdd);
137	u8 val;
138
 
139	/* First, reset timers as suggested by the docs */
140	esb_unlock_registers(edev);
141	writew(ESB_WDT_RELOAD, ESB_RELOAD_REG(edev));
142	/* Then disable the WDT */
143	pci_write_config_byte(edev->pdev, ESB_LOCK_REG, 0x0);
144	pci_read_config_byte(edev->pdev, ESB_LOCK_REG, &val);
 
145
146	/* Returns 0 if the timer was disabled, non-zero otherwise */
147	return val & ESB_WDT_ENABLE;
148}
149
150static int esb_timer_keepalive(struct watchdog_device *wdd)
151{
152	struct esb_dev *edev = to_esb_dev(wdd);
153
154	esb_unlock_registers(edev);
155	writew(ESB_WDT_RELOAD, ESB_RELOAD_REG(edev));
156	/* FIXME: Do we need to flush anything here? */
157	return 0;
158}
159
160static int esb_timer_set_heartbeat(struct watchdog_device *wdd,
161		unsigned int time)
162{
163	struct esb_dev *edev = to_esb_dev(wdd);
164	u32 val;
165
 
 
 
 
 
166	/* We shift by 9, so if we are passed a value of 1 sec,
167	 * val will be 1 << 9 = 512, then write that to two
168	 * timers => 2 * 512 = 1024 (which is decremented at 1KHz)
169	 */
170	val = time << 9;
171
172	/* Write timer 1 */
173	esb_unlock_registers(edev);
174	writel(val, ESB_TIMER1_REG(edev));
175
176	/* Write timer 2 */
177	esb_unlock_registers(edev);
178	writel(val, ESB_TIMER2_REG(edev));
179
180	/* Reload */
181	esb_unlock_registers(edev);
182	writew(ESB_WDT_RELOAD, ESB_RELOAD_REG(edev));
183
184	/* FIXME: Do we need to flush everything out? */
185
186	/* Done */
187	wdd->timeout = time;
 
188	return 0;
189}
190
191/*
192 * Watchdog Subsystem Interfaces
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
193 */
194
195static struct watchdog_info esb_info = {
196	.identity = ESB_MODULE_NAME,
197	.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
 
 
 
 
198};
199
200static const struct watchdog_ops esb_ops = {
201	.owner = THIS_MODULE,
202	.start = esb_timer_start,
203	.stop = esb_timer_stop,
204	.set_timeout = esb_timer_set_heartbeat,
205	.ping = esb_timer_keepalive,
206};
207
208/*
209 * Data for PCI driver interface
210 */
211static const struct pci_device_id esb_pci_tbl[] = {
212	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ESB_9), },
213	{ 0, },                 /* End of list */
214};
215MODULE_DEVICE_TABLE(pci, esb_pci_tbl);
216
217/*
218 *      Init & exit routines
219 */
220
221static unsigned char esb_getdevice(struct esb_dev *edev)
222{
223	if (pci_enable_device(edev->pdev)) {
224		dev_err(&edev->pdev->dev, "failed to enable device\n");
225		goto err_devput;
226	}
227
228	if (pci_request_region(edev->pdev, 0, ESB_MODULE_NAME)) {
229		dev_err(&edev->pdev->dev, "failed to request region\n");
230		goto err_disable;
231	}
232
233	edev->base = pci_ioremap_bar(edev->pdev, 0);
234	if (edev->base == NULL) {
235		/* Something's wrong here, BASEADDR has to be set */
236		dev_err(&edev->pdev->dev, "failed to get BASEADDR\n");
237		goto err_release;
238	}
239
240	/* Done */
241	dev_set_drvdata(&edev->pdev->dev, edev);
242	return 1;
243
244err_release:
245	pci_release_region(edev->pdev, 0);
246err_disable:
247	pci_disable_device(edev->pdev);
248err_devput:
249	return 0;
250}
251
252static void esb_initdevice(struct esb_dev *edev)
253{
254	u8 val1;
255	u16 val2;
256
257	/*
258	 * Config register:
259	 * Bit    5 : 0 = Enable WDT_OUTPUT
260	 * Bit    2 : 0 = set the timer frequency to the PCI clock
261	 * divided by 2^15 (approx 1KHz).
262	 * Bits 1:0 : 11 = WDT_INT_TYPE Disabled.
263	 * The watchdog has two timers, it can be setup so that the
264	 * expiry of timer1 results in an interrupt and the expiry of
265	 * timer2 results in a reboot. We set it to not generate
266	 * any interrupts as there is not much we can do with it
267	 * right now.
268	 */
269	pci_write_config_word(edev->pdev, ESB_CONFIG_REG, 0x0003);
270
271	/* Check that the WDT isn't already locked */
272	pci_read_config_byte(edev->pdev, ESB_LOCK_REG, &val1);
273	if (val1 & ESB_WDT_LOCK)
274		dev_warn(&edev->pdev->dev, "nowayout already set\n");
275
276	/* Set the timer to watchdog mode and disable it for now */
277	pci_write_config_byte(edev->pdev, ESB_LOCK_REG, 0x00);
278
279	/* Check if the watchdog was previously triggered */
280	esb_unlock_registers(edev);
281	val2 = readw(ESB_RELOAD_REG(edev));
282	if (val2 & ESB_WDT_TIMEOUT)
283		edev->wdd.bootstatus = WDIOF_CARDRESET;
284
285	/* Reset WDT_TIMEOUT flag and timers */
286	esb_unlock_registers(edev);
287	writew((ESB_WDT_TIMEOUT | ESB_WDT_RELOAD), ESB_RELOAD_REG(edev));
288
289	/* And set the correct timeout value */
290	esb_timer_set_heartbeat(&edev->wdd, edev->wdd.timeout);
291}
292
293static int esb_probe(struct pci_dev *pdev,
294		const struct pci_device_id *ent)
295{
296	struct esb_dev *edev;
297	int ret;
298
299	edev = devm_kzalloc(&pdev->dev, sizeof(*edev), GFP_KERNEL);
300	if (!edev)
301		return -ENOMEM;
 
 
 
 
 
 
302
303	/* Check whether or not the hardware watchdog is there */
304	edev->pdev = pdev;
305	if (!esb_getdevice(edev))
306		return -ENODEV;
307
 
 
 
 
 
 
 
 
 
308	/* Initialize the watchdog and make sure it does not run */
309	edev->wdd.info = &esb_info;
310	edev->wdd.ops = &esb_ops;
311	edev->wdd.min_timeout = ESB_HEARTBEAT_MIN;
312	edev->wdd.max_timeout = ESB_HEARTBEAT_MAX;
313	edev->wdd.timeout = ESB_HEARTBEAT_DEFAULT;
314	if (watchdog_init_timeout(&edev->wdd, heartbeat, NULL))
315		dev_info(&pdev->dev,
316			"heartbeat value must be " ESB_HEARTBEAT_RANGE
317			", using %u\n", edev->wdd.timeout);
318	watchdog_set_nowayout(&edev->wdd, nowayout);
319	watchdog_stop_on_reboot(&edev->wdd);
320	watchdog_stop_on_unregister(&edev->wdd);
321	esb_initdevice(edev);
322
323	/* Register the watchdog so that userspace has access to it */
324	ret = watchdog_register_device(&edev->wdd);
325	if (ret != 0) {
326		dev_err(&pdev->dev,
327			"cannot register watchdog device (err=%d)\n", ret);
 
328		goto err_unmap;
329	}
330	dev_info(&pdev->dev,
331		"initialized (0x%p). heartbeat=%d sec (nowayout=%d)\n",
332		edev->base, edev->wdd.timeout, nowayout);
333	return 0;
334
335err_unmap:
336	iounmap(edev->base);
337	pci_release_region(edev->pdev, 0);
338	pci_disable_device(edev->pdev);
 
339	return ret;
340}
341
342static void esb_remove(struct pci_dev *pdev)
343{
344	struct esb_dev *edev = dev_get_drvdata(&pdev->dev);
 
 
 
 
 
 
 
 
 
 
345
346	watchdog_unregister_device(&edev->wdd);
347	iounmap(edev->base);
348	pci_release_region(edev->pdev, 0);
349	pci_disable_device(edev->pdev);
350}
351
352static struct pci_driver esb_driver = {
353	.name		= ESB_MODULE_NAME,
354	.id_table	= esb_pci_tbl,
355	.probe          = esb_probe,
356	.remove         = esb_remove,
 
357};
358
359module_pci_driver(esb_driver);
 
 
 
 
 
 
 
 
 
 
 
 
360
361MODULE_AUTHOR("Ross Biro and David Härdeman");
362MODULE_DESCRIPTION("Watchdog driver for Intel 6300ESB chipsets");
363MODULE_LICENSE("GPL");