/* *	i8xx_tco:	TCO timer driver for i8xx chipsets * *	(c) Copyright 2000 kernel concepts <nils@kernelconcepts.de>, All Rights Reserved. *				http://www.kernelconcepts.de * *	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 kernel concepts nor Nils Faerber admit liability nor provide *	warranty for any of this software. This material is provided *	"AS-IS" and at no charge. * *	(c) Copyright 2000	kernel concepts <nils@kernelconcepts.de> *				developed for *                              Jentro AG, Haar/Munich (Germany) * *	TCO timer driver for i8xx chipsets *	based on softdog.c by Alan Cox <alan@redhat.com> * *	The TCO timer is implemented in the following I/O controller hubs: *	(See the intel documentation on http://developer.intel.com.) *	82801AA  (ICH)    : document number 290655-003, 290677-014, *	82801AB  (ICHO)   : document number 290655-003, 290677-014, *	82801BA  (ICH2)   : document number 290687-002, 298242-027, *	82801BAM (ICH2-M) : document number 290687-002, 298242-027, *	82801CA  (ICH3-S) : document number 290733-003, 290739-013, *	82801CAM (ICH3-M) : document number 290716-001, 290718-007, *	82801DB  (ICH4)   : document number 290744-001, 290745-020, *	82801DBM (ICH4-M) : document number 252337-001, 252663-005, *	82801E   (C-ICH)  : document number 273599-001, 273645-002, *	82801EB  (ICH5)   : document number 252516-001, 252517-003, *	82801ER  (ICH5R)  : document number 252516-001, 252517-003, *	82801FB  (ICH6)   : document number 301473-002, 301474-007, *	82801FR  (ICH6R)  : document number 301473-002, 301474-007, *	82801FBM (ICH6-M) : document number 301473-002, 301474-007, *	82801FW  (ICH6W)  : document number 301473-001, 301474-007, *	82801FRW (ICH6RW) : document number 301473-001, 301474-007 * *  20000710 Nils Faerber *	Initial Version 0.01 *  20000728 Nils Faerber *	0.02 Fix for SMI_EN->TCO_EN bit, some cleanups *  20011214 Matt Domsch <Matt_Domsch@dell.com> *	0.03 Added nowayout module option to override CONFIG_WATCHDOG_NOWAYOUT *	     Didn't add timeout option as i810_margin already exists. *  20020224 Joel Becker, Wim Van Sebroeck *	0.04 Support for 82801CA(M) chipset, timer margin needs to be > 3, *	     add support for WDIOC_SETTIMEOUT and WDIOC_GETTIMEOUT. *  20020412 Rob Radez <rob@osinvestor.com>, Wim Van Sebroeck *	0.05 Fix possible timer_alive race, add expect close support, *	     clean up ioctls (WDIOC_GETSTATUS, WDIOC_GETBOOTSTATUS and *	     WDIOC_SETOPTIONS), made i810tco_getdevice __init, *	     removed boot_status, removed tco_timer_read, *	     added support for 82801DB and 82801E chipset, *	     added support for 82801EB and 8280ER chipset, *	     general cleanup. *  20030921 Wim Van Sebroeck <wim@iguana.be> *	0.06 change i810_margin to heartbeat, use module_param, *	     added notify system support, renamed module to i8xx_tco. *  20050128 Wim Van Sebroeck <wim@iguana.be> *	0.07 Added support for the ICH4-M, ICH6, ICH6R, ICH6-M, ICH6W and ICH6RW *	     chipsets. Also added support for the "undocumented" ICH7 chipset. *  20050807 Wim Van Sebroeck <wim@iguana.be> *	0.08 Make sure that the watchdog is only "armed" when started. *	     (Kernel Bug 4251) *//* *	Includes, defines, variables, module parameters, ... */#include <linux/module.h>#include <linux/moduleparam.h>#include <linux/types.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 <asm/uaccess.h>#include <asm/io.h>#include "i8xx_tco.h"/* Module and version information */#define TCO_VERSION "0.08"#define TCO_MODULE_NAME "i8xx TCO timer"#define TCO_DRIVER_NAME   TCO_MODULE_NAME ", v" TCO_VERSION#define PFX TCO_MODULE_NAME ": "/* internal variables */static unsigned int ACPIBASE;static spinlock_t tco_lock;	/* Guards the hardware */static unsigned long timer_alive;static char tco_expect_close;static struct pci_dev *i8xx_tco_pci;/* module parameters */#define WATCHDOG_HEARTBEAT 30	/* 30 sec default heartbeat (2<heartbeat<39) */static int heartbeat = WATCHDOG_HEARTBEAT;  /* in seconds */module_param(heartbeat, int, 0);MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds. (2<heartbeat<39, 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)");/* * Some TCO specific functions */static inline unsigned char seconds_to_ticks(int seconds){	/* the internal timer is stored as ticks which decrement	 * every 0.6 seconds */	return (seconds * 10) / 6;}static int tco_timer_start (void){	unsigned char val;	spin_lock(&tco_lock);	/* disable chipset's NO_REBOOT bit */	pci_read_config_byte (i8xx_tco_pci, 0xd4, &val);	val &= 0xfd;	pci_write_config_byte (i8xx_tco_pci, 0xd4, val);	/* Bit 11: TCO Timer Halt -> 0 = The TCO timer is enabled to count */	val = inb (TCO1_CNT + 1);	val &= 0xf7;	outb (val, TCO1_CNT + 1);	val = inb (TCO1_CNT + 1);	spin_unlock(&tco_lock);	if (val & 0x08)		return -1;	return 0;}static int tco_timer_stop (void){	unsigned char val, val1;	spin_lock(&tco_lock);	/* Bit 11: TCO Timer Halt -> 1 = The TCO timer is disabled */	val = inb (TCO1_CNT + 1);	val |= 0x08;	outb (val, TCO1_CNT + 1);	val = inb (TCO1_CNT + 1);	/* Set the NO_REBOOT bit to prevent later reboots, just for sure */	pci_read_config_byte (i8xx_tco_pci, 0xd4, &val1);	val1 |= 0x02;	pci_write_config_byte (i8xx_tco_pci, 0xd4, val1);	spin_unlock(&tco_lock);	if ((val & 0x08) == 0)		return -1;	return 0;}static int tco_timer_keepalive (void){	spin_lock(&tco_lock);	/* Reload the timer by writing to the TCO Timer Reload register */	outb (0x01, TCO1_RLD);	spin_unlock(&tco_lock);	return 0;}static int tco_timer_set_heartbeat (int t){	unsigned char val;	unsigned char tmrval;	tmrval = seconds_to_ticks(t);	/* from the specs: */	/* "Values of 0h-3h are ignored and should not be attempted" */	if (tmrval > 0x3f || tmrval < 0x04)		return -EINVAL;	/* Write new heartbeat to watchdog */	spin_lock(&tco_lock);	val = inb (TCO1_TMR);	val &= 0xc0;	val |= tmrval;	outb (val, TCO1_TMR);	val = inb (TCO1_TMR);	spin_unlock(&tco_lock);	if ((val & 0x3f) != tmrval)		return -EINVAL;	heartbeat = t;	return 0;}/* *	/dev/watchdog handling */static int i8xx_tco_open (struct inode *inode, struct file *file){	/* /dev/watchdog can only be opened once */	if (test_and_set_bit(0, &timer_alive))		return -EBUSY;	/*	 *      Reload and activate timer	 */	tco_timer_keepalive ();	tco_timer_start ();	return nonseekable_open(inode, file);}static int i8xx_tco_release (struct inode *inode, struct file *file){	/*	 *      Shut off the timer.	 */	if (tco_expect_close == 42) {		tco_timer_stop ();	} else {		printk(KERN_CRIT PFX "Unexpected close, not stopping watchdog!\n");		tco_timer_keepalive ();	}	clear_bit(0, &timer_alive);	tco_expect_close = 0;	return 0;}static ssize_t i8xx_tco_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... */			tco_expect_close = 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')					tco_expect_close = 42;			}		}		/* someone wrote to us, we should reload the timer */		tco_timer_keepalive ();	}	return len;}static int i8xx_tco_ioctl (struct inode *inode, struct file *file,			  unsigned int cmd, unsigned long arg){	int new_options, retval = -EINVAL;	int new_heartbeat;	void __user *argp = (void __user *)arg;	int __user *p = argp;	static struct watchdog_info ident = {		.options =		WDIOF_SETTIMEOUT |					WDIOF_KEEPALIVEPING |					WDIOF_MAGICCLOSE,		.firmware_version =	0,		.identity =		TCO_MODULE_NAME,	};	switch (cmd) {		case WDIOC_GETSUPPORT:			return copy_to_user(argp, &ident,				sizeof (ident)) ? -EFAULT : 0;		case WDIOC_GETSTATUS:		case WDIOC_GETBOOTSTATUS:			return put_user (0, p);		case WDIOC_KEEPALIVE:			tco_timer_keepalive ();			return 0;		case WDIOC_SETOPTIONS:		{			if (get_user (new_options, p))				return -EFAULT;			if (new_options & WDIOS_DISABLECARD) {				tco_timer_stop ();				retval = 0;			}			if (new_options & WDIOS_ENABLECARD) {				tco_timer_keepalive ();				tco_timer_start ();				retval = 0;			}			return retval;		}		case WDIOC_SETTIMEOUT:		{			if (get_user(new_heartbeat, p))				return -EFAULT;			if (tco_timer_set_heartbeat(new_heartbeat))			    return -EINVAL;			tco_timer_keepalive ();			/* Fall */		}		case WDIOC_GETTIMEOUT:			return put_user(heartbeat, p);		default:			return -ENOIOCTLCMD;	}}/* *	Notify system */static int i8xx_tco_notify_sys (struct notifier_block *this, unsigned long code, void *unused){	if (code==SYS_DOWN || code==SYS_HALT) {		/* Turn the WDT off */		tco_timer_stop ();	}	return NOTIFY_DONE;}/* *	Kernel Interfaces */static struct file_operations i8xx_tco_fops = {	.owner =	THIS_MODULE,	.llseek =	no_llseek,	.write =	i8xx_tco_write,	.ioctl =	i8xx_tco_ioctl,	.open =		i8xx_tco_open,	.release =	i8xx_tco_release,};static struct miscdevice i8xx_tco_miscdev = {	.minor =	WATCHDOG_MINOR,	.name =		"watchdog",	.fops =		&i8xx_tco_fops,};static struct notifier_block i8xx_tco_notifier = {	.notifier_call =	i8xx_tco_notify_sys,};/* * Data for PCI driver interface * * This data only exists for exporting the supported * PCI ids via MODULE_DEVICE_TABLE.  We do not actually * register a pci_driver, because someone else might one day * want to register another driver on the same PCI id. */static struct pci_device_id i8xx_tco_pci_tbl[] = {	{ PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801AA_0,	PCI_ANY_ID, PCI_ANY_ID, },	{ PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801AB_0,	PCI_ANY_ID, PCI_ANY_ID, },	{ PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801BA_0,	PCI_ANY_ID, PCI_ANY_ID, },	{ PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801BA_10,	PCI_ANY_ID, PCI_ANY_ID, },	{ PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801CA_0,	PCI_ANY_ID, PCI_ANY_ID, },	{ PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801CA_12,	PCI_ANY_ID, PCI_ANY_ID, },	{ PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801DB_0,	PCI_ANY_ID, PCI_ANY_ID, },	{ PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801DB_12,	PCI_ANY_ID, PCI_ANY_ID, },	{ PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801E_0,	PCI_ANY_ID, PCI_ANY_ID, },	{ PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801EB_0,	PCI_ANY_ID, PCI_ANY_ID, },	{ PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH6_0,	PCI_ANY_ID, PCI_ANY_ID, },	{ PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH6_1,	PCI_ANY_ID, PCI_ANY_ID, },	{ PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH6_2,	PCI_ANY_ID, PCI_ANY_ID, },	{ PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH7_0,	PCI_ANY_ID, PCI_ANY_ID, },	{ PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH7_1,	PCI_ANY_ID, PCI_ANY_ID, },	{ PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ESB_1,	PCI_ANY_ID, PCI_ANY_ID, },	{ 0, },			/* End of list */};MODULE_DEVICE_TABLE (pci, i8xx_tco_pci_tbl);/* *	Init & exit routines */static unsigned char __init i8xx_tco_getdevice (void){	struct pci_dev *dev = NULL;	u8 val1, val2;	u16 badr;	/*	 *      Find the PCI device	 */	while ((dev = pci_find_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) {		if (pci_match_id(i8xx_tco_pci_tbl, dev)) {			i8xx_tco_pci = dev;			break;		}	}	if (i8xx_tco_pci) {		/*		 *      Find the ACPI base I/O address which is the base		 *      for the TCO registers (TCOBASE=ACPIBASE + 0x60)		 *      ACPIBASE is bits [15:7] from 0x40-0x43		 */		pci_read_config_byte (i8xx_tco_pci, 0x40, &val1);		pci_read_config_byte (i8xx_tco_pci, 0x41, &val2);		badr = ((val2 << 1) | (val1 >> 7)) << 7;		ACPIBASE = badr;		/* Something's wrong here, ACPIBASE has to be set */		if (badr == 0x0001 || badr == 0x0000) {			printk (KERN_ERR PFX "failed to get TCOBASE address\n");			return 0;		}		/* Check chipset's NO_REBOOT bit */		pci_read_config_byte (i8xx_tco_pci, 0xd4, &val1);		if (val1 & 0x02) {			val1 &= 0xfd;			pci_write_config_byte (i8xx_tco_pci, 0xd4, val1);			pci_read_config_byte (i8xx_tco_pci, 0xd4, &val1);			if (val1 & 0x02) {				printk (KERN_ERR PFX "failed to reset NO_REBOOT flag, reboot disabled by hardware\n");				return 0;	/* Cannot reset NO_REBOOT bit */			}		}		/* Disable reboots untill the watchdog starts */		val1 |= 0x02;		pci_write_config_byte (i8xx_tco_pci, 0xd4, val1);		/* Set the TCO_EN bit in SMI_EN register */		if (!request_region (SMI_EN + 1, 1, "i8xx TCO")) {			printk (KERN_ERR PFX "I/O address 0x%04x already in use\n",				SMI_EN + 1);			return 0;		}		val1 = inb (SMI_EN + 1);		val1 &= 0xdf;		outb (val1, SMI_EN + 1);		release_region (SMI_EN + 1, 1);		return 1;	}	return 0;}static int __init watchdog_init (void){	int ret;	spin_lock_init(&tco_lock);	/* Check whether or not the hardware watchdog is there */	if (!i8xx_tco_getdevice () || i8xx_tco_pci == NULL)		return -ENODEV;	if (!request_region (TCOBASE, 0x10, "i8xx TCO")) {		printk (KERN_ERR PFX "I/O address 0x%04x already in use\n",			TCOBASE);		ret = -EIO;		goto out;	}	/* Clear out the (probably old) status */	outb (0, TCO1_STS);	outb (3, TCO2_STS);	/* Check that the heartbeat value is within it's range ; if not reset to the default */	if (tco_timer_set_heartbeat (heartbeat)) {		heartbeat = WATCHDOG_HEARTBEAT;		tco_timer_set_heartbeat (heartbeat);		printk(KERN_INFO PFX "heartbeat value must be 2<heartbeat<39, using %d\n",			heartbeat);	}	ret = register_reboot_notifier(&i8xx_tco_notifier);	if (ret != 0) {		printk(KERN_ERR PFX "cannot register reboot notifier (err=%d)\n",			ret);		goto unreg_region;	}	ret = misc_register(&i8xx_tco_miscdev);	if (ret != 0) {		printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",			WATCHDOG_MINOR, ret);		goto unreg_notifier;	}	tco_timer_stop ();	printk (KERN_INFO PFX "initialized (0x%04x). heartbeat=%d sec (nowayout=%d)\n",		TCOBASE, heartbeat, nowayout);	return 0;unreg_notifier:	unregister_reboot_notifier(&i8xx_tco_notifier);unreg_region:	release_region (TCOBASE, 0x10);out:	return ret;}static void __exit watchdog_cleanup (void){	/* Stop the timer before we leave */	if (!nowayout)		tco_timer_stop ();	/* Deregister */	misc_deregister (&i8xx_tco_miscdev);	unregister_reboot_notifier(&i8xx_tco_notifier);	release_region (TCOBASE, 0x10);}module_init(watchdog_init);module_exit(watchdog_cleanup);MODULE_AUTHOR("Nils Faerber");MODULE_DESCRIPTION("TCO timer driver for i8xx chipsets");MODULE_LICENSE("GPL");MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);