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v6.13.7
  1// SPDX-License-Identifier: GPL-2.0+
  2/*
  3 *	intel TCO Watchdog Driver
  4 *
  5 *	(c) Copyright 2006-2011 Wim Van Sebroeck <wim@iguana.be>.
  6 *
 
 
 
 
 
  7 *	Neither Wim Van Sebroeck nor Iguana vzw. admit liability nor
  8 *	provide warranty for any of this software. This material is
  9 *	provided "AS-IS" and at no charge.
 10 *
 11 *	The TCO watchdog is implemented in the following I/O controller hubs:
 12 *	(See the intel documentation on http://developer.intel.com.)
 13 *	document number 290655-003, 290677-014: 82801AA (ICH), 82801AB (ICHO)
 14 *	document number 290687-002, 298242-027: 82801BA (ICH2)
 15 *	document number 290733-003, 290739-013: 82801CA (ICH3-S)
 16 *	document number 290716-001, 290718-007: 82801CAM (ICH3-M)
 17 *	document number 290744-001, 290745-025: 82801DB (ICH4)
 18 *	document number 252337-001, 252663-008: 82801DBM (ICH4-M)
 19 *	document number 273599-001, 273645-002: 82801E (C-ICH)
 20 *	document number 252516-001, 252517-028: 82801EB (ICH5), 82801ER (ICH5R)
 21 *	document number 300641-004, 300884-013: 6300ESB
 22 *	document number 301473-002, 301474-026: 82801F (ICH6)
 23 *	document number 313082-001, 313075-006: 631xESB, 632xESB
 24 *	document number 307013-003, 307014-024: 82801G (ICH7)
 25 *	document number 322896-001, 322897-001: NM10
 26 *	document number 313056-003, 313057-017: 82801H (ICH8)
 27 *	document number 316972-004, 316973-012: 82801I (ICH9)
 28 *	document number 319973-002, 319974-002: 82801J (ICH10)
 29 *	document number 322169-001, 322170-003: 5 Series, 3400 Series (PCH)
 30 *	document number 320066-003, 320257-008: EP80597 (IICH)
 31 *	document number 324645-001, 324646-001: Cougar Point (CPT)
 32 *	document number TBD                   : Patsburg (PBG)
 33 *	document number TBD                   : DH89xxCC
 34 *	document number TBD                   : Panther Point
 35 *	document number TBD                   : Lynx Point
 36 *	document number TBD                   : Lynx Point-LP
 37 */
 38
 39/*
 40 *	Includes, defines, variables, module parameters, ...
 41 */
 42
 
 
 43/* Module and version information */
 44#define DRV_NAME	"iTCO_wdt"
 45#define DRV_VERSION	"1.11"
 46
 47/* Includes */
 48#include <linux/acpi.h>			/* For ACPI support */
 49#include <linux/bits.h>			/* For BIT() */
 50#include <linux/module.h>		/* For module specific items */
 51#include <linux/moduleparam.h>		/* For new moduleparam's */
 52#include <linux/types.h>		/* For standard types (like size_t) */
 53#include <linux/errno.h>		/* For the -ENODEV/... values */
 54#include <linux/kernel.h>		/* For printk/panic/... */
 55#include <linux/watchdog.h>		/* For the watchdog specific items */
 56#include <linux/init.h>			/* For __init/__exit/... */
 57#include <linux/fs.h>			/* For file operations */
 58#include <linux/platform_device.h>	/* For platform_driver framework */
 59#include <linux/pci.h>			/* For pci functions */
 60#include <linux/ioport.h>		/* For io-port access */
 61#include <linux/spinlock.h>		/* For spin_lock/spin_unlock/... */
 62#include <linux/uaccess.h>		/* For copy_to_user/put_user/... */
 63#include <linux/io.h>			/* For inb/outb/... */
 64#include <linux/platform_data/itco_wdt.h>
 65#include <linux/mfd/intel_pmc_bxt.h>
 66
 67#include "iTCO_vendor.h"
 68
 69/* Address definitions for the TCO */
 70/* TCO base address */
 71#define TCOBASE(p)	((p)->tco_res->start)
 72/* SMI Control and Enable Register */
 73#define SMI_EN(p)	((p)->smi_res->start)
 74
 75#define TCO_RLD(p)	(TCOBASE(p) + 0x00) /* TCO Timer Reload/Curr. Value */
 76#define TCOv1_TMR(p)	(TCOBASE(p) + 0x01) /* TCOv1 Timer Initial Value*/
 77#define TCO_DAT_IN(p)	(TCOBASE(p) + 0x02) /* TCO Data In Register	*/
 78#define TCO_DAT_OUT(p)	(TCOBASE(p) + 0x03) /* TCO Data Out Register	*/
 79#define TCO1_STS(p)	(TCOBASE(p) + 0x04) /* TCO1 Status Register	*/
 80#define TCO2_STS(p)	(TCOBASE(p) + 0x06) /* TCO2 Status Register	*/
 81#define TCO1_CNT(p)	(TCOBASE(p) + 0x08) /* TCO1 Control Register	*/
 82#define TCO2_CNT(p)	(TCOBASE(p) + 0x0a) /* TCO2 Control Register	*/
 83#define TCOv2_TMR(p)	(TCOBASE(p) + 0x12) /* TCOv2 Timer Initial Value*/
 84
 85/*
 86 * NMI_NOW is bit 8 of TCO1_CNT register
 87 * Read/Write
 88 * This bit is implemented as RW but has no effect on HW.
 89 */
 90#define NMI_NOW		BIT(8)
 91
 92/* internal variables */
 93struct iTCO_wdt_private {
 94	struct watchdog_device wddev;
 95
 96	/* TCO version/generation */
 97	unsigned int iTCO_version;
 98	struct resource *tco_res;
 99	struct resource *smi_res;
100	/*
101	 * NO_REBOOT flag is Memory-Mapped GCS register bit 5 (TCO version 2),
102	 * or memory-mapped PMC register bit 4 (TCO version 3).
103	 */
 
104	unsigned long __iomem *gcs_pmc;
105	/* the lock for io operations */
106	spinlock_t io_lock;
107	/* the PCI-device */
108	struct pci_dev *pci_dev;
109	/* whether or not the watchdog has been suspended */
110	bool suspended;
111	/* no reboot API private data */
112	void *no_reboot_priv;
113	/* no reboot update function pointer */
114	int (*update_no_reboot_bit)(void *p, bool set);
115};
116
117/* module parameters */
118#define WATCHDOG_TIMEOUT 30	/* 30 sec default heartbeat */
119static int heartbeat = WATCHDOG_TIMEOUT;  /* in seconds */
120module_param(heartbeat, int, 0);
121MODULE_PARM_DESC(heartbeat, "Watchdog timeout in seconds. "
122	"5..76 (TCO v1) or 3..614 (TCO v2), default="
123				__MODULE_STRING(WATCHDOG_TIMEOUT) ")");
124
125static bool nowayout = WATCHDOG_NOWAYOUT;
126module_param(nowayout, bool, 0);
127MODULE_PARM_DESC(nowayout,
128	"Watchdog cannot be stopped once started (default="
129				__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
130
131static int turn_SMI_watchdog_clear_off = 1;
132module_param(turn_SMI_watchdog_clear_off, int, 0);
133MODULE_PARM_DESC(turn_SMI_watchdog_clear_off,
134	"Turn off SMI clearing watchdog (depends on TCO-version)(default=1)");
135
136/*
137 * Some TCO specific functions
138 */
139
140/*
141 * The iTCO v1 and v2's internal timer is stored as ticks which decrement
142 * every 0.6 seconds.  v3's internal timer is stored as seconds (some
143 * datasheets incorrectly state 0.6 seconds).
144 */
145static inline unsigned int seconds_to_ticks(struct iTCO_wdt_private *p,
146					    int secs)
147{
148	return p->iTCO_version == 3 ? secs : (secs * 10) / 6;
149}
150
151static inline unsigned int ticks_to_seconds(struct iTCO_wdt_private *p,
152					    int ticks)
153{
154	return p->iTCO_version == 3 ? ticks : (ticks * 6) / 10;
155}
156
157static inline u32 no_reboot_bit(struct iTCO_wdt_private *p)
158{
159	u32 enable_bit;
160
161	switch (p->iTCO_version) {
162	case 5:
163	case 3:
164		enable_bit = 0x00000010;
165		break;
166	case 2:
167		enable_bit = 0x00000020;
168		break;
169	case 4:
170	case 1:
171	default:
172		enable_bit = 0x00000002;
173		break;
174	}
175
176	return enable_bit;
177}
178
179static int update_no_reboot_bit_def(void *priv, bool set)
180{
181	return 0;
182}
183
184static int update_no_reboot_bit_pci(void *priv, bool set)
185{
186	struct iTCO_wdt_private *p = priv;
187	u32 val32 = 0, newval32 = 0;
188
189	pci_read_config_dword(p->pci_dev, 0xd4, &val32);
190	if (set)
191		val32 |= no_reboot_bit(p);
192	else
193		val32 &= ~no_reboot_bit(p);
194	pci_write_config_dword(p->pci_dev, 0xd4, val32);
195	pci_read_config_dword(p->pci_dev, 0xd4, &newval32);
196
197	/* make sure the update is successful */
198	if (val32 != newval32)
199		return -EIO;
200
201	return 0;
202}
203
204static int update_no_reboot_bit_mem(void *priv, bool set)
205{
206	struct iTCO_wdt_private *p = priv;
207	u32 val32 = 0, newval32 = 0;
208
209	val32 = readl(p->gcs_pmc);
210	if (set)
211		val32 |= no_reboot_bit(p);
212	else
213		val32 &= ~no_reboot_bit(p);
214	writel(val32, p->gcs_pmc);
215	newval32 = readl(p->gcs_pmc);
216
217	/* make sure the update is successful */
218	if (val32 != newval32)
219		return -EIO;
220
221	return 0;
222}
223
224static int update_no_reboot_bit_cnt(void *priv, bool set)
225{
226	struct iTCO_wdt_private *p = priv;
227	u16 val, newval;
228
229	/*
230	 * writing back 1b1 to NMI_NOW of TCO1_CNT register
231	 * causes NMI_NOW bit inversion what consequently does
232	 * not allow to perform the register's value comparison
233	 * properly.
234	 *
235	 * NMI_NOW bit masking for TCO1_CNT register values
236	 * helps to avoid possible NMI_NOW bit inversions on
237	 * following write operation.
238	 */
239	val = inw(TCO1_CNT(p)) & ~NMI_NOW;
240	if (set)
241		val |= BIT(0);
242	else
243		val &= ~BIT(0);
244	outw(val, TCO1_CNT(p));
245	newval = inw(TCO1_CNT(p)) & ~NMI_NOW;
246
247	/* make sure the update is successful */
248	return val != newval ? -EIO : 0;
249}
250
251static int update_no_reboot_bit_pmc(void *priv, bool set)
252{
253	struct intel_pmc_dev *pmc = priv;
254	u32 bits = PMC_CFG_NO_REBOOT_EN;
255	u32 value = set ? bits : 0;
256
257	return intel_pmc_gcr_update(pmc, PMC_GCR_PMC_CFG_REG, bits, value);
258}
259
260static void iTCO_wdt_no_reboot_bit_setup(struct iTCO_wdt_private *p,
261					 struct platform_device *pdev,
262					 struct itco_wdt_platform_data *pdata)
263{
264	if (pdata->no_reboot_use_pmc) {
265		struct intel_pmc_dev *pmc = dev_get_drvdata(pdev->dev.parent);
266
267		p->update_no_reboot_bit = update_no_reboot_bit_pmc;
268		p->no_reboot_priv = pmc;
269		return;
270	}
271
272	if (p->iTCO_version >= 6)
273		p->update_no_reboot_bit = update_no_reboot_bit_cnt;
274	else if (p->iTCO_version >= 2)
275		p->update_no_reboot_bit = update_no_reboot_bit_mem;
276	else if (p->iTCO_version == 1)
277		p->update_no_reboot_bit = update_no_reboot_bit_pci;
278	else
279		p->update_no_reboot_bit = update_no_reboot_bit_def;
280
281	p->no_reboot_priv = p;
282}
283
284static int iTCO_wdt_start(struct watchdog_device *wd_dev)
285{
286	struct iTCO_wdt_private *p = watchdog_get_drvdata(wd_dev);
287	unsigned int val;
288
289	spin_lock(&p->io_lock);
290
291	iTCO_vendor_pre_start(p->smi_res, wd_dev->timeout);
292
293	/* disable chipset's NO_REBOOT bit */
294	if (p->update_no_reboot_bit(p->no_reboot_priv, false)) {
295		spin_unlock(&p->io_lock);
296		dev_err(wd_dev->parent, "failed to reset NO_REBOOT flag, reboot disabled by hardware/BIOS\n");
297		return -EIO;
298	}
299
300	/* Force the timer to its reload value by writing to the TCO_RLD
301	   register */
302	if (p->iTCO_version >= 2)
303		outw(0x01, TCO_RLD(p));
304	else if (p->iTCO_version == 1)
305		outb(0x01, TCO_RLD(p));
306
307	/* Bit 11: TCO Timer Halt -> 0 = The TCO timer is enabled to count */
308	val = inw(TCO1_CNT(p));
309	val &= 0xf7ff;
310	outw(val, TCO1_CNT(p));
311	val = inw(TCO1_CNT(p));
312	spin_unlock(&p->io_lock);
313
314	if (val & 0x0800)
315		return -1;
316	return 0;
317}
318
319static int iTCO_wdt_stop(struct watchdog_device *wd_dev)
320{
321	struct iTCO_wdt_private *p = watchdog_get_drvdata(wd_dev);
322	unsigned int val;
323
324	spin_lock(&p->io_lock);
325
326	iTCO_vendor_pre_stop(p->smi_res);
327
328	/* Bit 11: TCO Timer Halt -> 1 = The TCO timer is disabled */
329	val = inw(TCO1_CNT(p));
330	val |= 0x0800;
331	outw(val, TCO1_CNT(p));
332	val = inw(TCO1_CNT(p));
333
334	/* Set the NO_REBOOT bit to prevent later reboots, just for sure */
335	p->update_no_reboot_bit(p->no_reboot_priv, true);
336
337	spin_unlock(&p->io_lock);
338
339	if ((val & 0x0800) == 0)
340		return -1;
341	return 0;
342}
343
344static int iTCO_wdt_ping(struct watchdog_device *wd_dev)
345{
346	struct iTCO_wdt_private *p = watchdog_get_drvdata(wd_dev);
347
348	spin_lock(&p->io_lock);
349
 
 
350	/* Reload the timer by writing to the TCO Timer Counter register */
351	if (p->iTCO_version >= 2) {
352		outw(0x01, TCO_RLD(p));
353	} else if (p->iTCO_version == 1) {
354		/* Reset the timeout status bit so that the timer
355		 * needs to count down twice again before rebooting */
356		outw(0x0008, TCO1_STS(p));	/* write 1 to clear bit */
357
358		outb(0x01, TCO_RLD(p));
359	}
360
361	spin_unlock(&p->io_lock);
362	return 0;
363}
364
365static int iTCO_wdt_set_timeout(struct watchdog_device *wd_dev, unsigned int t)
366{
367	struct iTCO_wdt_private *p = watchdog_get_drvdata(wd_dev);
368	unsigned int val16;
369	unsigned char val8;
370	unsigned int tmrval;
371
372	tmrval = seconds_to_ticks(p, t);
373
374	/* For TCO v1 the timer counts down twice before rebooting */
375	if (p->iTCO_version == 1)
376		tmrval /= 2;
377
378	/* from the specs: */
379	/* "Values of 0h-3h are ignored and should not be attempted" */
380	if (tmrval < 0x04)
381		return -EINVAL;
382	if ((p->iTCO_version >= 2 && tmrval > 0x3ff) ||
383	    (p->iTCO_version == 1 && tmrval > 0x03f))
384		return -EINVAL;
385
 
 
386	/* Write new heartbeat to watchdog */
387	if (p->iTCO_version >= 2) {
388		spin_lock(&p->io_lock);
389		val16 = inw(TCOv2_TMR(p));
390		val16 &= 0xfc00;
391		val16 |= tmrval;
392		outw(val16, TCOv2_TMR(p));
393		val16 = inw(TCOv2_TMR(p));
394		spin_unlock(&p->io_lock);
395
396		if ((val16 & 0x3ff) != tmrval)
397			return -EINVAL;
398	} else if (p->iTCO_version == 1) {
399		spin_lock(&p->io_lock);
400		val8 = inb(TCOv1_TMR(p));
401		val8 &= 0xc0;
402		val8 |= (tmrval & 0xff);
403		outb(val8, TCOv1_TMR(p));
404		val8 = inb(TCOv1_TMR(p));
405		spin_unlock(&p->io_lock);
406
407		if ((val8 & 0x3f) != tmrval)
408			return -EINVAL;
409	}
410
411	wd_dev->timeout = t;
412	return 0;
413}
414
415static unsigned int iTCO_wdt_get_timeleft(struct watchdog_device *wd_dev)
416{
417	struct iTCO_wdt_private *p = watchdog_get_drvdata(wd_dev);
418	unsigned int val16;
419	unsigned char val8;
420	unsigned int time_left = 0;
421
422	/* read the TCO Timer */
423	if (p->iTCO_version >= 2) {
424		spin_lock(&p->io_lock);
425		val16 = inw(TCO_RLD(p));
426		val16 &= 0x3ff;
427		spin_unlock(&p->io_lock);
428
429		time_left = ticks_to_seconds(p, val16);
430	} else if (p->iTCO_version == 1) {
431		spin_lock(&p->io_lock);
432		val8 = inb(TCO_RLD(p));
433		val8 &= 0x3f;
434		if (!(inw(TCO1_STS(p)) & 0x0008))
435			val8 += (inb(TCOv1_TMR(p)) & 0x3f);
436		spin_unlock(&p->io_lock);
437
438		time_left = ticks_to_seconds(p, val8);
439	}
440	return time_left;
441}
442
443/* Returns true if the watchdog was running */
444static bool iTCO_wdt_set_running(struct iTCO_wdt_private *p)
445{
446	u16 val;
447
448	/* Bit 11: TCO Timer Halt -> 0 = The TCO timer is enabled */
449	val = inw(TCO1_CNT(p));
450	if (!(val & BIT(11))) {
451		set_bit(WDOG_HW_RUNNING, &p->wddev.status);
452		return true;
453	}
454	return false;
455}
456
457/*
458 *	Kernel Interfaces
459 */
460
461static struct watchdog_info ident = {
462	.options =		WDIOF_SETTIMEOUT |
463				WDIOF_KEEPALIVEPING |
464				WDIOF_MAGICCLOSE,
 
465	.identity =		DRV_NAME,
466};
467
468static const struct watchdog_ops iTCO_wdt_ops = {
469	.owner =		THIS_MODULE,
470	.start =		iTCO_wdt_start,
471	.stop =			iTCO_wdt_stop,
472	.ping =			iTCO_wdt_ping,
473	.set_timeout =		iTCO_wdt_set_timeout,
474	.get_timeleft =		iTCO_wdt_get_timeleft,
475};
476
477/*
478 *	Init & exit routines
479 */
480
481static int iTCO_wdt_probe(struct platform_device *pdev)
482{
483	struct device *dev = &pdev->dev;
484	struct itco_wdt_platform_data *pdata = dev_get_platdata(dev);
485	struct iTCO_wdt_private *p;
486	unsigned long val32;
487	int ret;
488
489	if (!pdata)
490		return -ENODEV;
491
492	p = devm_kzalloc(dev, sizeof(*p), GFP_KERNEL);
493	if (!p)
494		return -ENOMEM;
495
496	spin_lock_init(&p->io_lock);
497
498	p->tco_res = platform_get_resource(pdev, IORESOURCE_IO, ICH_RES_IO_TCO);
499	if (!p->tco_res)
500		return -ENODEV;
501
502	p->iTCO_version = pdata->version;
503	p->pci_dev = to_pci_dev(dev->parent);
504
505	p->smi_res = platform_get_resource(pdev, IORESOURCE_IO, ICH_RES_IO_SMI);
506	if (p->smi_res) {
507		/* The TCO logic uses the TCO_EN bit in the SMI_EN register */
508		if (!devm_request_region(dev, p->smi_res->start,
509					 resource_size(p->smi_res),
510					 pdev->name)) {
511			dev_err(dev, "I/O address 0x%04llx already in use, device disabled\n",
512			       (u64)SMI_EN(p));
513			return -EBUSY;
514		}
515	} else if (iTCO_vendorsupport ||
516		   turn_SMI_watchdog_clear_off >= p->iTCO_version) {
517		dev_err(dev, "SMI I/O resource is missing\n");
518		return -ENODEV;
519	}
520
521	iTCO_wdt_no_reboot_bit_setup(p, pdev, pdata);
 
 
 
522
523	/*
524	 * Get the Memory-Mapped GCS or PMC register, we need it for the
525	 * NO_REBOOT flag (TCO v2 and v3).
526	 */
527	if (p->iTCO_version >= 2 && p->iTCO_version < 6 &&
528	    !pdata->no_reboot_use_pmc) {
529		p->gcs_pmc = devm_platform_ioremap_resource(pdev, ICH_RES_MEM_GCS_PMC);
 
 
530		if (IS_ERR(p->gcs_pmc))
531			return PTR_ERR(p->gcs_pmc);
532	}
533
534	/* Check chipset's NO_REBOOT bit */
535	if (p->update_no_reboot_bit(p->no_reboot_priv, false) &&
536	    iTCO_vendor_check_noreboot_on()) {
537		dev_info(dev, "unable to reset NO_REBOOT flag, device disabled by hardware/BIOS\n");
538		return -ENODEV;	/* Cannot reset NO_REBOOT bit */
539	}
540
 
 
 
 
 
 
 
 
 
 
 
541	if (turn_SMI_watchdog_clear_off >= p->iTCO_version) {
542		/*
543		 * Bit 13: TCO_EN -> 0
544		 * Disables TCO logic generating an SMI#
545		 */
546		val32 = inl(SMI_EN(p));
547		val32 &= 0xffffdfff;	/* Turn off SMI clearing watchdog */
548		outl(val32, SMI_EN(p));
549	}
550
551	if (!devm_request_region(dev, p->tco_res->start,
552				 resource_size(p->tco_res),
553				 pdev->name)) {
554		dev_err(dev, "I/O address 0x%04llx already in use, device disabled\n",
555		       (u64)TCOBASE(p));
556		return -EBUSY;
557	}
558
559	dev_info(dev, "Found a %s TCO device (Version=%d, TCOBASE=0x%04llx)\n",
560		pdata->name, pdata->version, (u64)TCOBASE(p));
561
562	/* Clear out the (probably old) status */
563	switch (p->iTCO_version) {
564	case 6:
565	case 5:
566	case 4:
567		outw(0x0008, TCO1_STS(p)); /* Clear the Time Out Status bit */
568		outw(0x0002, TCO2_STS(p)); /* Clear SECOND_TO_STS bit */
569		break;
570	case 3:
571		outl(0x20008, TCO1_STS(p));
572		break;
573	case 2:
574	case 1:
575	default:
576		outw(0x0008, TCO1_STS(p)); /* Clear the Time Out Status bit */
577		outw(0x0002, TCO2_STS(p)); /* Clear SECOND_TO_STS bit */
578		outw(0x0004, TCO2_STS(p)); /* Clear BOOT_STS bit */
579		break;
580	}
581
582	ident.firmware_version = p->iTCO_version;
583	p->wddev.info = &ident;
584	p->wddev.ops = &iTCO_wdt_ops;
585	p->wddev.bootstatus = 0;
586	p->wddev.timeout = WATCHDOG_TIMEOUT;
587	watchdog_set_nowayout(&p->wddev, nowayout);
588	p->wddev.parent = dev;
589
590	watchdog_set_drvdata(&p->wddev, p);
591	platform_set_drvdata(pdev, p);
592
593	if (!iTCO_wdt_set_running(p)) {
594		/*
595		 * If the watchdog was not running set NO_REBOOT now to
596		 * prevent later reboots.
597		 */
598		p->update_no_reboot_bit(p->no_reboot_priv, true);
599	}
600
601	/* Check that the heartbeat value is within it's range;
602	   if not reset to the default */
603	if (iTCO_wdt_set_timeout(&p->wddev, heartbeat)) {
604		iTCO_wdt_set_timeout(&p->wddev, WATCHDOG_TIMEOUT);
605		dev_info(dev, "timeout value out of range, using %d\n",
606			WATCHDOG_TIMEOUT);
607	}
608
609	watchdog_stop_on_reboot(&p->wddev);
610	watchdog_stop_on_unregister(&p->wddev);
611	ret = devm_watchdog_register_device(dev, &p->wddev);
612	if (ret != 0)
 
613		return ret;
 
614
615	dev_info(dev, "initialized. heartbeat=%d sec (nowayout=%d)\n",
616		heartbeat, nowayout);
617
618	return 0;
619}
620
 
 
 
 
 
 
 
 
 
 
 
 
621/*
622 * Suspend-to-idle requires this, because it stops the ticks and timekeeping, so
623 * the watchdog cannot be pinged while in that state.  In ACPI sleep states the
624 * watchdog is stopped by the platform firmware.
625 */
626
627#ifdef CONFIG_ACPI
628static inline bool __maybe_unused need_suspend(void)
629{
630	return acpi_target_system_state() == ACPI_STATE_S0;
631}
632#else
633static inline bool __maybe_unused need_suspend(void) { return true; }
634#endif
635
636static int __maybe_unused iTCO_wdt_suspend_noirq(struct device *dev)
637{
638	struct iTCO_wdt_private *p = dev_get_drvdata(dev);
639	int ret = 0;
640
641	p->suspended = false;
642	if (watchdog_active(&p->wddev) && need_suspend()) {
643		ret = iTCO_wdt_stop(&p->wddev);
644		if (!ret)
645			p->suspended = true;
646	}
647	return ret;
648}
649
650static int __maybe_unused iTCO_wdt_resume_noirq(struct device *dev)
651{
652	struct iTCO_wdt_private *p = dev_get_drvdata(dev);
653
654	if (p->suspended)
655		iTCO_wdt_start(&p->wddev);
656
657	return 0;
658}
659
660static const struct dev_pm_ops iTCO_wdt_pm = {
661	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(iTCO_wdt_suspend_noirq,
662				      iTCO_wdt_resume_noirq)
663};
664
 
 
 
 
 
665static struct platform_driver iTCO_wdt_driver = {
666	.probe          = iTCO_wdt_probe,
 
667	.driver         = {
668		.name   = DRV_NAME,
669		.pm     = &iTCO_wdt_pm,
670	},
671};
672
673module_platform_driver(iTCO_wdt_driver);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
674
675MODULE_AUTHOR("Wim Van Sebroeck <wim@iguana.be>");
676MODULE_DESCRIPTION("Intel TCO WatchDog Timer Driver");
677MODULE_VERSION(DRV_VERSION);
678MODULE_LICENSE("GPL");
679MODULE_ALIAS("platform:" DRV_NAME);
v4.17
 
  1/*
  2 *	intel TCO Watchdog Driver
  3 *
  4 *	(c) Copyright 2006-2011 Wim Van Sebroeck <wim@iguana.be>.
  5 *
  6 *	This program is free software; you can redistribute it and/or
  7 *	modify it under the terms of the GNU General Public License
  8 *	as published by the Free Software Foundation; either version
  9 *	2 of the License, or (at your option) any later version.
 10 *
 11 *	Neither Wim Van Sebroeck nor Iguana vzw. admit liability nor
 12 *	provide warranty for any of this software. This material is
 13 *	provided "AS-IS" and at no charge.
 14 *
 15 *	The TCO watchdog is implemented in the following I/O controller hubs:
 16 *	(See the intel documentation on http://developer.intel.com.)
 17 *	document number 290655-003, 290677-014: 82801AA (ICH), 82801AB (ICHO)
 18 *	document number 290687-002, 298242-027: 82801BA (ICH2)
 19 *	document number 290733-003, 290739-013: 82801CA (ICH3-S)
 20 *	document number 290716-001, 290718-007: 82801CAM (ICH3-M)
 21 *	document number 290744-001, 290745-025: 82801DB (ICH4)
 22 *	document number 252337-001, 252663-008: 82801DBM (ICH4-M)
 23 *	document number 273599-001, 273645-002: 82801E (C-ICH)
 24 *	document number 252516-001, 252517-028: 82801EB (ICH5), 82801ER (ICH5R)
 25 *	document number 300641-004, 300884-013: 6300ESB
 26 *	document number 301473-002, 301474-026: 82801F (ICH6)
 27 *	document number 313082-001, 313075-006: 631xESB, 632xESB
 28 *	document number 307013-003, 307014-024: 82801G (ICH7)
 29 *	document number 322896-001, 322897-001: NM10
 30 *	document number 313056-003, 313057-017: 82801H (ICH8)
 31 *	document number 316972-004, 316973-012: 82801I (ICH9)
 32 *	document number 319973-002, 319974-002: 82801J (ICH10)
 33 *	document number 322169-001, 322170-003: 5 Series, 3400 Series (PCH)
 34 *	document number 320066-003, 320257-008: EP80597 (IICH)
 35 *	document number 324645-001, 324646-001: Cougar Point (CPT)
 36 *	document number TBD                   : Patsburg (PBG)
 37 *	document number TBD                   : DH89xxCC
 38 *	document number TBD                   : Panther Point
 39 *	document number TBD                   : Lynx Point
 40 *	document number TBD                   : Lynx Point-LP
 41 */
 42
 43/*
 44 *	Includes, defines, variables, module parameters, ...
 45 */
 46
 47#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 48
 49/* Module and version information */
 50#define DRV_NAME	"iTCO_wdt"
 51#define DRV_VERSION	"1.11"
 52
 53/* Includes */
 54#include <linux/acpi.h>			/* For ACPI support */
 
 55#include <linux/module.h>		/* For module specific items */
 56#include <linux/moduleparam.h>		/* For new moduleparam's */
 57#include <linux/types.h>		/* For standard types (like size_t) */
 58#include <linux/errno.h>		/* For the -ENODEV/... values */
 59#include <linux/kernel.h>		/* For printk/panic/... */
 60#include <linux/watchdog.h>		/* For the watchdog specific items */
 61#include <linux/init.h>			/* For __init/__exit/... */
 62#include <linux/fs.h>			/* For file operations */
 63#include <linux/platform_device.h>	/* For platform_driver framework */
 64#include <linux/pci.h>			/* For pci functions */
 65#include <linux/ioport.h>		/* For io-port access */
 66#include <linux/spinlock.h>		/* For spin_lock/spin_unlock/... */
 67#include <linux/uaccess.h>		/* For copy_to_user/put_user/... */
 68#include <linux/io.h>			/* For inb/outb/... */
 69#include <linux/platform_data/itco_wdt.h>
 
 70
 71#include "iTCO_vendor.h"
 72
 73/* Address definitions for the TCO */
 74/* TCO base address */
 75#define TCOBASE(p)	((p)->tco_res->start)
 76/* SMI Control and Enable Register */
 77#define SMI_EN(p)	((p)->smi_res->start)
 78
 79#define TCO_RLD(p)	(TCOBASE(p) + 0x00) /* TCO Timer Reload/Curr. Value */
 80#define TCOv1_TMR(p)	(TCOBASE(p) + 0x01) /* TCOv1 Timer Initial Value*/
 81#define TCO_DAT_IN(p)	(TCOBASE(p) + 0x02) /* TCO Data In Register	*/
 82#define TCO_DAT_OUT(p)	(TCOBASE(p) + 0x03) /* TCO Data Out Register	*/
 83#define TCO1_STS(p)	(TCOBASE(p) + 0x04) /* TCO1 Status Register	*/
 84#define TCO2_STS(p)	(TCOBASE(p) + 0x06) /* TCO2 Status Register	*/
 85#define TCO1_CNT(p)	(TCOBASE(p) + 0x08) /* TCO1 Control Register	*/
 86#define TCO2_CNT(p)	(TCOBASE(p) + 0x0a) /* TCO2 Control Register	*/
 87#define TCOv2_TMR(p)	(TCOBASE(p) + 0x12) /* TCOv2 Timer Initial Value*/
 88
 
 
 
 
 
 
 
 89/* internal variables */
 90struct iTCO_wdt_private {
 91	struct watchdog_device wddev;
 92
 93	/* TCO version/generation */
 94	unsigned int iTCO_version;
 95	struct resource *tco_res;
 96	struct resource *smi_res;
 97	/*
 98	 * NO_REBOOT flag is Memory-Mapped GCS register bit 5 (TCO version 2),
 99	 * or memory-mapped PMC register bit 4 (TCO version 3).
100	 */
101	struct resource *gcs_pmc_res;
102	unsigned long __iomem *gcs_pmc;
103	/* the lock for io operations */
104	spinlock_t io_lock;
105	/* the PCI-device */
106	struct pci_dev *pci_dev;
107	/* whether or not the watchdog has been suspended */
108	bool suspended;
109	/* no reboot API private data */
110	void *no_reboot_priv;
111	/* no reboot update function pointer */
112	int (*update_no_reboot_bit)(void *p, bool set);
113};
114
115/* module parameters */
116#define WATCHDOG_TIMEOUT 30	/* 30 sec default heartbeat */
117static int heartbeat = WATCHDOG_TIMEOUT;  /* in seconds */
118module_param(heartbeat, int, 0);
119MODULE_PARM_DESC(heartbeat, "Watchdog timeout in seconds. "
120	"5..76 (TCO v1) or 3..614 (TCO v2), default="
121				__MODULE_STRING(WATCHDOG_TIMEOUT) ")");
122
123static bool nowayout = WATCHDOG_NOWAYOUT;
124module_param(nowayout, bool, 0);
125MODULE_PARM_DESC(nowayout,
126	"Watchdog cannot be stopped once started (default="
127				__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
128
129static int turn_SMI_watchdog_clear_off = 1;
130module_param(turn_SMI_watchdog_clear_off, int, 0);
131MODULE_PARM_DESC(turn_SMI_watchdog_clear_off,
132	"Turn off SMI clearing watchdog (depends on TCO-version)(default=1)");
133
134/*
135 * Some TCO specific functions
136 */
137
138/*
139 * The iTCO v1 and v2's internal timer is stored as ticks which decrement
140 * every 0.6 seconds.  v3's internal timer is stored as seconds (some
141 * datasheets incorrectly state 0.6 seconds).
142 */
143static inline unsigned int seconds_to_ticks(struct iTCO_wdt_private *p,
144					    int secs)
145{
146	return p->iTCO_version == 3 ? secs : (secs * 10) / 6;
147}
148
149static inline unsigned int ticks_to_seconds(struct iTCO_wdt_private *p,
150					    int ticks)
151{
152	return p->iTCO_version == 3 ? ticks : (ticks * 6) / 10;
153}
154
155static inline u32 no_reboot_bit(struct iTCO_wdt_private *p)
156{
157	u32 enable_bit;
158
159	switch (p->iTCO_version) {
160	case 5:
161	case 3:
162		enable_bit = 0x00000010;
163		break;
164	case 2:
165		enable_bit = 0x00000020;
166		break;
167	case 4:
168	case 1:
169	default:
170		enable_bit = 0x00000002;
171		break;
172	}
173
174	return enable_bit;
175}
176
177static int update_no_reboot_bit_def(void *priv, bool set)
178{
179	return 0;
180}
181
182static int update_no_reboot_bit_pci(void *priv, bool set)
183{
184	struct iTCO_wdt_private *p = priv;
185	u32 val32 = 0, newval32 = 0;
186
187	pci_read_config_dword(p->pci_dev, 0xd4, &val32);
188	if (set)
189		val32 |= no_reboot_bit(p);
190	else
191		val32 &= ~no_reboot_bit(p);
192	pci_write_config_dword(p->pci_dev, 0xd4, val32);
193	pci_read_config_dword(p->pci_dev, 0xd4, &newval32);
194
195	/* make sure the update is successful */
196	if (val32 != newval32)
197		return -EIO;
198
199	return 0;
200}
201
202static int update_no_reboot_bit_mem(void *priv, bool set)
203{
204	struct iTCO_wdt_private *p = priv;
205	u32 val32 = 0, newval32 = 0;
206
207	val32 = readl(p->gcs_pmc);
208	if (set)
209		val32 |= no_reboot_bit(p);
210	else
211		val32 &= ~no_reboot_bit(p);
212	writel(val32, p->gcs_pmc);
213	newval32 = readl(p->gcs_pmc);
214
215	/* make sure the update is successful */
216	if (val32 != newval32)
217		return -EIO;
218
219	return 0;
220}
221
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
222static void iTCO_wdt_no_reboot_bit_setup(struct iTCO_wdt_private *p,
223		struct itco_wdt_platform_data *pdata)
 
224{
225	if (pdata->update_no_reboot_bit) {
226		p->update_no_reboot_bit = pdata->update_no_reboot_bit;
227		p->no_reboot_priv = pdata->no_reboot_priv;
 
 
228		return;
229	}
230
231	if (p->iTCO_version >= 2)
 
 
232		p->update_no_reboot_bit = update_no_reboot_bit_mem;
233	else if (p->iTCO_version == 1)
234		p->update_no_reboot_bit = update_no_reboot_bit_pci;
235	else
236		p->update_no_reboot_bit = update_no_reboot_bit_def;
237
238	p->no_reboot_priv = p;
239}
240
241static int iTCO_wdt_start(struct watchdog_device *wd_dev)
242{
243	struct iTCO_wdt_private *p = watchdog_get_drvdata(wd_dev);
244	unsigned int val;
245
246	spin_lock(&p->io_lock);
247
248	iTCO_vendor_pre_start(p->smi_res, wd_dev->timeout);
249
250	/* disable chipset's NO_REBOOT bit */
251	if (p->update_no_reboot_bit(p->no_reboot_priv, false)) {
252		spin_unlock(&p->io_lock);
253		pr_err("failed to reset NO_REBOOT flag, reboot disabled by hardware/BIOS\n");
254		return -EIO;
255	}
256
257	/* Force the timer to its reload value by writing to the TCO_RLD
258	   register */
259	if (p->iTCO_version >= 2)
260		outw(0x01, TCO_RLD(p));
261	else if (p->iTCO_version == 1)
262		outb(0x01, TCO_RLD(p));
263
264	/* Bit 11: TCO Timer Halt -> 0 = The TCO timer is enabled to count */
265	val = inw(TCO1_CNT(p));
266	val &= 0xf7ff;
267	outw(val, TCO1_CNT(p));
268	val = inw(TCO1_CNT(p));
269	spin_unlock(&p->io_lock);
270
271	if (val & 0x0800)
272		return -1;
273	return 0;
274}
275
276static int iTCO_wdt_stop(struct watchdog_device *wd_dev)
277{
278	struct iTCO_wdt_private *p = watchdog_get_drvdata(wd_dev);
279	unsigned int val;
280
281	spin_lock(&p->io_lock);
282
283	iTCO_vendor_pre_stop(p->smi_res);
284
285	/* Bit 11: TCO Timer Halt -> 1 = The TCO timer is disabled */
286	val = inw(TCO1_CNT(p));
287	val |= 0x0800;
288	outw(val, TCO1_CNT(p));
289	val = inw(TCO1_CNT(p));
290
291	/* Set the NO_REBOOT bit to prevent later reboots, just for sure */
292	p->update_no_reboot_bit(p->no_reboot_priv, true);
293
294	spin_unlock(&p->io_lock);
295
296	if ((val & 0x0800) == 0)
297		return -1;
298	return 0;
299}
300
301static int iTCO_wdt_ping(struct watchdog_device *wd_dev)
302{
303	struct iTCO_wdt_private *p = watchdog_get_drvdata(wd_dev);
304
305	spin_lock(&p->io_lock);
306
307	iTCO_vendor_pre_keepalive(p->smi_res, wd_dev->timeout);
308
309	/* Reload the timer by writing to the TCO Timer Counter register */
310	if (p->iTCO_version >= 2) {
311		outw(0x01, TCO_RLD(p));
312	} else if (p->iTCO_version == 1) {
313		/* Reset the timeout status bit so that the timer
314		 * needs to count down twice again before rebooting */
315		outw(0x0008, TCO1_STS(p));	/* write 1 to clear bit */
316
317		outb(0x01, TCO_RLD(p));
318	}
319
320	spin_unlock(&p->io_lock);
321	return 0;
322}
323
324static int iTCO_wdt_set_timeout(struct watchdog_device *wd_dev, unsigned int t)
325{
326	struct iTCO_wdt_private *p = watchdog_get_drvdata(wd_dev);
327	unsigned int val16;
328	unsigned char val8;
329	unsigned int tmrval;
330
331	tmrval = seconds_to_ticks(p, t);
332
333	/* For TCO v1 the timer counts down twice before rebooting */
334	if (p->iTCO_version == 1)
335		tmrval /= 2;
336
337	/* from the specs: */
338	/* "Values of 0h-3h are ignored and should not be attempted" */
339	if (tmrval < 0x04)
340		return -EINVAL;
341	if ((p->iTCO_version >= 2 && tmrval > 0x3ff) ||
342	    (p->iTCO_version == 1 && tmrval > 0x03f))
343		return -EINVAL;
344
345	iTCO_vendor_pre_set_heartbeat(tmrval);
346
347	/* Write new heartbeat to watchdog */
348	if (p->iTCO_version >= 2) {
349		spin_lock(&p->io_lock);
350		val16 = inw(TCOv2_TMR(p));
351		val16 &= 0xfc00;
352		val16 |= tmrval;
353		outw(val16, TCOv2_TMR(p));
354		val16 = inw(TCOv2_TMR(p));
355		spin_unlock(&p->io_lock);
356
357		if ((val16 & 0x3ff) != tmrval)
358			return -EINVAL;
359	} else if (p->iTCO_version == 1) {
360		spin_lock(&p->io_lock);
361		val8 = inb(TCOv1_TMR(p));
362		val8 &= 0xc0;
363		val8 |= (tmrval & 0xff);
364		outb(val8, TCOv1_TMR(p));
365		val8 = inb(TCOv1_TMR(p));
366		spin_unlock(&p->io_lock);
367
368		if ((val8 & 0x3f) != tmrval)
369			return -EINVAL;
370	}
371
372	wd_dev->timeout = t;
373	return 0;
374}
375
376static unsigned int iTCO_wdt_get_timeleft(struct watchdog_device *wd_dev)
377{
378	struct iTCO_wdt_private *p = watchdog_get_drvdata(wd_dev);
379	unsigned int val16;
380	unsigned char val8;
381	unsigned int time_left = 0;
382
383	/* read the TCO Timer */
384	if (p->iTCO_version >= 2) {
385		spin_lock(&p->io_lock);
386		val16 = inw(TCO_RLD(p));
387		val16 &= 0x3ff;
388		spin_unlock(&p->io_lock);
389
390		time_left = ticks_to_seconds(p, val16);
391	} else if (p->iTCO_version == 1) {
392		spin_lock(&p->io_lock);
393		val8 = inb(TCO_RLD(p));
394		val8 &= 0x3f;
395		if (!(inw(TCO1_STS(p)) & 0x0008))
396			val8 += (inb(TCOv1_TMR(p)) & 0x3f);
397		spin_unlock(&p->io_lock);
398
399		time_left = ticks_to_seconds(p, val8);
400	}
401	return time_left;
402}
403
 
 
 
 
 
 
 
 
 
 
 
 
 
 
404/*
405 *	Kernel Interfaces
406 */
407
408static const struct watchdog_info ident = {
409	.options =		WDIOF_SETTIMEOUT |
410				WDIOF_KEEPALIVEPING |
411				WDIOF_MAGICCLOSE,
412	.firmware_version =	0,
413	.identity =		DRV_NAME,
414};
415
416static const struct watchdog_ops iTCO_wdt_ops = {
417	.owner =		THIS_MODULE,
418	.start =		iTCO_wdt_start,
419	.stop =			iTCO_wdt_stop,
420	.ping =			iTCO_wdt_ping,
421	.set_timeout =		iTCO_wdt_set_timeout,
422	.get_timeleft =		iTCO_wdt_get_timeleft,
423};
424
425/*
426 *	Init & exit routines
427 */
428
429static int iTCO_wdt_probe(struct platform_device *pdev)
430{
431	struct device *dev = &pdev->dev;
432	struct itco_wdt_platform_data *pdata = dev_get_platdata(dev);
433	struct iTCO_wdt_private *p;
434	unsigned long val32;
435	int ret;
436
437	if (!pdata)
438		return -ENODEV;
439
440	p = devm_kzalloc(dev, sizeof(*p), GFP_KERNEL);
441	if (!p)
442		return -ENOMEM;
443
444	spin_lock_init(&p->io_lock);
445
446	p->tco_res = platform_get_resource(pdev, IORESOURCE_IO, ICH_RES_IO_TCO);
447	if (!p->tco_res)
448		return -ENODEV;
449
 
 
 
450	p->smi_res = platform_get_resource(pdev, IORESOURCE_IO, ICH_RES_IO_SMI);
451	if (!p->smi_res)
 
 
 
 
 
 
 
 
 
 
 
452		return -ENODEV;
 
453
454	p->iTCO_version = pdata->version;
455	p->pci_dev = to_pci_dev(dev->parent);
456
457	iTCO_wdt_no_reboot_bit_setup(p, pdata);
458
459	/*
460	 * Get the Memory-Mapped GCS or PMC register, we need it for the
461	 * NO_REBOOT flag (TCO v2 and v3).
462	 */
463	if (p->iTCO_version >= 2 && !pdata->update_no_reboot_bit) {
464		p->gcs_pmc_res = platform_get_resource(pdev,
465						       IORESOURCE_MEM,
466						       ICH_RES_MEM_GCS_PMC);
467		p->gcs_pmc = devm_ioremap_resource(dev, p->gcs_pmc_res);
468		if (IS_ERR(p->gcs_pmc))
469			return PTR_ERR(p->gcs_pmc);
470	}
471
472	/* Check chipset's NO_REBOOT bit */
473	if (p->update_no_reboot_bit(p->no_reboot_priv, false) &&
474	    iTCO_vendor_check_noreboot_on()) {
475		pr_info("unable to reset NO_REBOOT flag, device disabled by hardware/BIOS\n");
476		return -ENODEV;	/* Cannot reset NO_REBOOT bit */
477	}
478
479	/* Set the NO_REBOOT bit to prevent later reboots, just for sure */
480	p->update_no_reboot_bit(p->no_reboot_priv, true);
481
482	/* The TCO logic uses the TCO_EN bit in the SMI_EN register */
483	if (!devm_request_region(dev, p->smi_res->start,
484				 resource_size(p->smi_res),
485				 pdev->name)) {
486		pr_err("I/O address 0x%04llx already in use, device disabled\n",
487		       (u64)SMI_EN(p));
488		return -EBUSY;
489	}
490	if (turn_SMI_watchdog_clear_off >= p->iTCO_version) {
491		/*
492		 * Bit 13: TCO_EN -> 0
493		 * Disables TCO logic generating an SMI#
494		 */
495		val32 = inl(SMI_EN(p));
496		val32 &= 0xffffdfff;	/* Turn off SMI clearing watchdog */
497		outl(val32, SMI_EN(p));
498	}
499
500	if (!devm_request_region(dev, p->tco_res->start,
501				 resource_size(p->tco_res),
502				 pdev->name)) {
503		pr_err("I/O address 0x%04llx already in use, device disabled\n",
504		       (u64)TCOBASE(p));
505		return -EBUSY;
506	}
507
508	pr_info("Found a %s TCO device (Version=%d, TCOBASE=0x%04llx)\n",
509		pdata->name, pdata->version, (u64)TCOBASE(p));
510
511	/* Clear out the (probably old) status */
512	switch (p->iTCO_version) {
 
513	case 5:
514	case 4:
515		outw(0x0008, TCO1_STS(p)); /* Clear the Time Out Status bit */
516		outw(0x0002, TCO2_STS(p)); /* Clear SECOND_TO_STS bit */
517		break;
518	case 3:
519		outl(0x20008, TCO1_STS(p));
520		break;
521	case 2:
522	case 1:
523	default:
524		outw(0x0008, TCO1_STS(p)); /* Clear the Time Out Status bit */
525		outw(0x0002, TCO2_STS(p)); /* Clear SECOND_TO_STS bit */
526		outw(0x0004, TCO2_STS(p)); /* Clear BOOT_STS bit */
527		break;
528	}
529
530	p->wddev.info =	&ident,
531	p->wddev.ops = &iTCO_wdt_ops,
 
532	p->wddev.bootstatus = 0;
533	p->wddev.timeout = WATCHDOG_TIMEOUT;
534	watchdog_set_nowayout(&p->wddev, nowayout);
535	p->wddev.parent = dev;
536
537	watchdog_set_drvdata(&p->wddev, p);
538	platform_set_drvdata(pdev, p);
539
540	/* Make sure the watchdog is not running */
541	iTCO_wdt_stop(&p->wddev);
 
 
 
 
 
542
543	/* Check that the heartbeat value is within it's range;
544	   if not reset to the default */
545	if (iTCO_wdt_set_timeout(&p->wddev, heartbeat)) {
546		iTCO_wdt_set_timeout(&p->wddev, WATCHDOG_TIMEOUT);
547		pr_info("timeout value out of range, using %d\n",
548			WATCHDOG_TIMEOUT);
549	}
550
551	watchdog_stop_on_reboot(&p->wddev);
 
552	ret = devm_watchdog_register_device(dev, &p->wddev);
553	if (ret != 0) {
554		pr_err("cannot register watchdog device (err=%d)\n", ret);
555		return ret;
556	}
557
558	pr_info("initialized. heartbeat=%d sec (nowayout=%d)\n",
559		heartbeat, nowayout);
560
561	return 0;
562}
563
564static int iTCO_wdt_remove(struct platform_device *pdev)
565{
566	struct iTCO_wdt_private *p = platform_get_drvdata(pdev);
567
568	/* Stop the timer before we leave */
569	if (!nowayout)
570		iTCO_wdt_stop(&p->wddev);
571
572	return 0;
573}
574
575#ifdef CONFIG_PM_SLEEP
576/*
577 * Suspend-to-idle requires this, because it stops the ticks and timekeeping, so
578 * the watchdog cannot be pinged while in that state.  In ACPI sleep states the
579 * watchdog is stopped by the platform firmware.
580 */
581
582#ifdef CONFIG_ACPI
583static inline bool need_suspend(void)
584{
585	return acpi_target_system_state() == ACPI_STATE_S0;
586}
587#else
588static inline bool need_suspend(void) { return true; }
589#endif
590
591static int iTCO_wdt_suspend_noirq(struct device *dev)
592{
593	struct iTCO_wdt_private *p = dev_get_drvdata(dev);
594	int ret = 0;
595
596	p->suspended = false;
597	if (watchdog_active(&p->wddev) && need_suspend()) {
598		ret = iTCO_wdt_stop(&p->wddev);
599		if (!ret)
600			p->suspended = true;
601	}
602	return ret;
603}
604
605static int iTCO_wdt_resume_noirq(struct device *dev)
606{
607	struct iTCO_wdt_private *p = dev_get_drvdata(dev);
608
609	if (p->suspended)
610		iTCO_wdt_start(&p->wddev);
611
612	return 0;
613}
614
615static const struct dev_pm_ops iTCO_wdt_pm = {
616	.suspend_noirq = iTCO_wdt_suspend_noirq,
617	.resume_noirq = iTCO_wdt_resume_noirq,
618};
619
620#define ITCO_WDT_PM_OPS	(&iTCO_wdt_pm)
621#else
622#define ITCO_WDT_PM_OPS	NULL
623#endif /* CONFIG_PM_SLEEP */
624
625static struct platform_driver iTCO_wdt_driver = {
626	.probe          = iTCO_wdt_probe,
627	.remove         = iTCO_wdt_remove,
628	.driver         = {
629		.name   = DRV_NAME,
630		.pm     = ITCO_WDT_PM_OPS,
631	},
632};
633
634static int __init iTCO_wdt_init_module(void)
635{
636	pr_info("Intel TCO WatchDog Timer Driver v%s\n", DRV_VERSION);
637
638	return platform_driver_register(&iTCO_wdt_driver);
639}
640
641static void __exit iTCO_wdt_cleanup_module(void)
642{
643	platform_driver_unregister(&iTCO_wdt_driver);
644	pr_info("Watchdog Module Unloaded\n");
645}
646
647module_init(iTCO_wdt_init_module);
648module_exit(iTCO_wdt_cleanup_module);
649
650MODULE_AUTHOR("Wim Van Sebroeck <wim@iguana.be>");
651MODULE_DESCRIPTION("Intel TCO WatchDog Timer Driver");
652MODULE_VERSION(DRV_VERSION);
653MODULE_LICENSE("GPL");
654MODULE_ALIAS("platform:" DRV_NAME);