/*
* 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,
*
* 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)
* 20060416 Wim Van Sebroeck <wim@iguana.be>
* 0.09 Remove support for the ICH6, ICH6R, ICH6-M, ICH6W and ICH6RW and
* ICH7 chipsets. (See Kernel Bug 6031 - other code will support these
* chipsets)
*/
/*
* 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 "0.09"
#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=" __MODULE_STRING(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;
}
static int tco_timer_get_timeleft (int *time_left)
{
unsigned char val;
spin_lock(&tco_lock);
/* read the TCO Timer */
val = inb (TCO1_RLD);
val &= 0x3f;
spin_unlock(&tco_lock);
*time_left = (int)((val * 6) / 10);
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;
int time_left;
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);
case WDIOC_GETTIMELEFT:
{
if (tco_timer_get_timeleft(&time_left))
return -EINVAL;
return put_user(time_left, p);
}
default:
return -ENOTTY;
}
}
/*
* 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 const 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_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801AA_0) },
{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801AB_0) },
{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801BA_0) },
{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801BA_10) },
{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801CA_0) },
{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801CA_12) },
{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801DB_0) },
{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801DB_12) },
{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801E_0) },
{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801EB_0) },
{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ESB_1) },
{ }, /* 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
*/
for_each_pci_dev(dev)
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");
pci_dev_put(i8xx_tco_pci);
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");
pci_dev_put(i8xx_tco_pci);
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);
pci_dev_put(i8xx_tco_pci);
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:
pci_dev_put(i8xx_tco_pci);
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);
pci_dev_put(i8xx_tco_pci);
}
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);
