Commit 47c44594 authored by Linus Torvalds's avatar Linus Torvalds

Merge http://linux-watchdog.bkbits.net/linux-2.5-watchdog

into home.osdl.org:/home/torvalds/v2.5/linux
parents e5dbafd4 e26d4f47
/* /*
* ALi M7101 PMU Computer Watchdog Timer driver for Linux 2.4.x * ALi M7101 PMU Computer Watchdog Timer driver
* *
* Based on w83877f_wdt.c by Scott Jennings <management@oro.net> * Based on w83877f_wdt.c by Scott Jennings <linuxdrivers@oro.net>
* and the Cobalt kernel WDT timer driver by Tim Hockin * and the Cobalt kernel WDT timer driver by Tim Hockin
* <thockin@cobaltnet.com> * <thockin@cobaltnet.com>
* *
* (c)2002 Steve Hill <steve@navaho.co.uk> * (c)2002 Steve Hill <steve@navaho.co.uk>
*
* Theory of operation:
* A Watchdog Timer (WDT) is a hardware circuit that can
* reset the computer system in case of a software fault.
* You probably knew that already.
*
* Usually a userspace daemon will notify the kernel WDT driver
* via the /proc/watchdog special device file that userspace is
* still alive, at regular intervals. When such a notification
* occurs, the driver will usually tell the hardware watchdog
* that everything is in order, and that the watchdog should wait
* for yet another little while to reset the system.
* If userspace fails (RAM error, kernel bug, whatever), the
* notifications cease to occur, and the hardware watchdog will
* reset the system (causing a reboot) after the timeout occurs.
* *
* This WDT driver is different from most other Linux WDT * This WDT driver is different from most other Linux WDT
* drivers in that the driver will ping the watchdog by itself, * drivers in that the driver will ping the watchdog by itself,
...@@ -30,6 +15,7 @@ ...@@ -30,6 +15,7 @@
*/ */
#include <linux/module.h> #include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/types.h> #include <linux/types.h>
#include <linux/timer.h> #include <linux/timer.h>
#include <linux/miscdevice.h> #include <linux/miscdevice.h>
...@@ -38,7 +24,6 @@ ...@@ -38,7 +24,6 @@
#include <linux/notifier.h> #include <linux/notifier.h>
#include <linux/reboot.h> #include <linux/reboot.h>
#include <linux/init.h> #include <linux/init.h>
#include <linux/moduleparam.h>
#include <linux/pci.h> #include <linux/pci.h>
#include <asm/io.h> #include <asm/io.h>
...@@ -46,6 +31,7 @@ ...@@ -46,6 +31,7 @@
#include <asm/system.h> #include <asm/system.h>
#define OUR_NAME "alim7101_wdt" #define OUR_NAME "alim7101_wdt"
#define PFX OUR_NAME ": "
#define WDT_ENABLE 0x9C #define WDT_ENABLE 0x9C
#define WDT_DISABLE 0x8C #define WDT_DISABLE 0x8C
...@@ -65,13 +51,16 @@ ...@@ -65,13 +51,16 @@
* char to /dev/watchdog every 30 seconds. * char to /dev/watchdog every 30 seconds.
*/ */
#define WDT_HEARTBEAT (HZ * 30) #define WATCHDOG_TIMEOUT 30 /* 30 sec default timeout */
static int timeout = WATCHDOG_TIMEOUT; /* in seconds, will be multiplied by HZ to get seconds to wait for a ping */
module_param(timeout, int, 0);
MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds. (1<=timeout<=3600, default=" __MODULE_STRING(WATCHDOG_TIMEOUT) ")");
static void wdt_timer_ping(unsigned long); static void wdt_timer_ping(unsigned long);
static struct timer_list timer; static struct timer_list timer;
static unsigned long next_heartbeat; static unsigned long next_heartbeat;
static unsigned long wdt_is_open; static unsigned long wdt_is_open;
static int wdt_expect_close; static char wdt_expect_close;
static struct pci_dev *alim7101_pmu; static struct pci_dev *alim7101_pmu;
#ifdef CONFIG_WATCHDOG_NOWAYOUT #ifdef CONFIG_WATCHDOG_NOWAYOUT
...@@ -79,7 +68,7 @@ static int nowayout = 1; ...@@ -79,7 +68,7 @@ static int nowayout = 1;
#else #else
static int nowayout = 0; static int nowayout = 0;
#endif #endif
module_param(nowayout, int, 0); module_param(nowayout, int, 0);
MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=CONFIG_WATCHDOG_NOWAYOUT)"); MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=CONFIG_WATCHDOG_NOWAYOUT)");
...@@ -90,25 +79,25 @@ MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=CON ...@@ -90,25 +79,25 @@ MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=CON
static void wdt_timer_ping(unsigned long data) static void wdt_timer_ping(unsigned long data)
{ {
/* If we got a heartbeat pulse within the WDT_US_INTERVAL /* If we got a heartbeat pulse within the WDT_US_INTERVAL
* we agree to ping the WDT * we agree to ping the WDT
*/ */
char tmp; char tmp;
if(time_before(jiffies, next_heartbeat)) if(time_before(jiffies, next_heartbeat))
{ {
/* Ping the WDT (this is actually a disarm/arm sequence) */ /* Ping the WDT (this is actually a disarm/arm sequence) */
pci_read_config_byte(alim7101_pmu, 0x92, &tmp); pci_read_config_byte(alim7101_pmu, 0x92, &tmp);
pci_write_config_byte(alim7101_pmu, ALI_7101_WDT, (tmp & ~ALI_WDT_ARM)); pci_write_config_byte(alim7101_pmu, ALI_7101_WDT, (tmp & ~ALI_WDT_ARM));
pci_write_config_byte(alim7101_pmu, ALI_7101_WDT, (tmp | ALI_WDT_ARM)); pci_write_config_byte(alim7101_pmu, ALI_7101_WDT, (tmp | ALI_WDT_ARM));
} else { } else {
printk(KERN_INFO OUR_NAME ": Heartbeat lost! Will not ping the watchdog\n"); printk(KERN_WARNING PFX "Heartbeat lost! Will not ping the watchdog\n");
} }
/* Re-set the timer interval */ /* Re-set the timer interval */
timer.expires = jiffies + WDT_INTERVAL; timer.expires = jiffies + WDT_INTERVAL;
add_timer(&timer); add_timer(&timer);
} }
/* /*
* Utility routines * Utility routines
*/ */
...@@ -125,7 +114,7 @@ static void wdt_change(int writeval) ...@@ -125,7 +114,7 @@ static void wdt_change(int writeval)
static void wdt_startup(void) static void wdt_startup(void)
{ {
next_heartbeat = jiffies + WDT_HEARTBEAT; next_heartbeat = jiffies + (timeout * HZ);
/* We must enable before we kick off the timer in case the timer /* We must enable before we kick off the timer in case the timer
occurs as we ping it */ occurs as we ping it */
...@@ -133,11 +122,11 @@ static void wdt_startup(void) ...@@ -133,11 +122,11 @@ static void wdt_startup(void)
wdt_change(WDT_ENABLE); wdt_change(WDT_ENABLE);
/* Start the timer */ /* Start the timer */
timer.expires = jiffies + WDT_INTERVAL; timer.expires = jiffies + WDT_INTERVAL;
add_timer(&timer); add_timer(&timer);
printk(KERN_INFO OUR_NAME ": Watchdog timer is now enabled.\n"); printk(KERN_INFO PFX "Watchdog timer is now enabled.\n");
} }
static void wdt_turnoff(void) static void wdt_turnoff(void)
...@@ -145,7 +134,13 @@ static void wdt_turnoff(void) ...@@ -145,7 +134,13 @@ static void wdt_turnoff(void)
/* Stop the timer */ /* Stop the timer */
del_timer_sync(&timer); del_timer_sync(&timer);
wdt_change(WDT_DISABLE); wdt_change(WDT_DISABLE);
printk(KERN_INFO OUR_NAME ": Watchdog timer is now disabled...\n"); printk(KERN_INFO PFX "Watchdog timer is now disabled...\n");
}
static void wdt_keepalive(void)
{
/* user land ping */
next_heartbeat = jiffies + (timeout * HZ);
} }
/* /*
...@@ -158,7 +153,7 @@ static ssize_t fop_write(struct file * file, const char * buf, size_t count, lof ...@@ -158,7 +153,7 @@ static ssize_t fop_write(struct file * file, const char * buf, size_t count, lof
if(ppos != &file->f_pos) if(ppos != &file->f_pos)
return -ESPIPE; return -ESPIPE;
/* See if we got the magic character */ /* See if we got the magic character 'V' and reload the timer */
if(count) { if(count) {
if (!nowayout) { if (!nowayout) {
size_t ofs; size_t ofs;
...@@ -173,14 +168,13 @@ static ssize_t fop_write(struct file * file, const char * buf, size_t count, lof ...@@ -173,14 +168,13 @@ static ssize_t fop_write(struct file * file, const char * buf, size_t count, lof
if (get_user(c, buf+ofs)) if (get_user(c, buf+ofs))
return -EFAULT; return -EFAULT;
if (c == 'V') if (c == 'V')
wdt_expect_close = 1; wdt_expect_close = 42;
} }
} }
/* someone wrote to us, we should restart timer */ /* someone wrote to us, we should restart timer */
next_heartbeat = jiffies + WDT_HEARTBEAT; wdt_keepalive();
return 1; }
}; return count;
return 0;
} }
static int fop_open(struct inode * inode, struct file * file) static int fop_open(struct inode * inode, struct file * file)
...@@ -195,12 +189,14 @@ static int fop_open(struct inode * inode, struct file * file) ...@@ -195,12 +189,14 @@ static int fop_open(struct inode * inode, struct file * file)
static int fop_close(struct inode * inode, struct file * file) static int fop_close(struct inode * inode, struct file * file)
{ {
if(wdt_expect_close) if(wdt_expect_close == 42)
wdt_turnoff(); wdt_turnoff();
else else {
printk(KERN_INFO OUR_NAME ": device file closed unexpectedly. Will not stop the WDT!\n"); /* wim: shouldn't there be a: del_timer(&timer); */
printk(KERN_CRIT PFX "device file closed unexpectedly. Will not stop the WDT!\n");
}
clear_bit(0, &wdt_is_open); clear_bit(0, &wdt_is_open);
wdt_expect_close = 0;
return 0; return 0;
} }
...@@ -208,20 +204,58 @@ static int fop_ioctl(struct inode *inode, struct file *file, unsigned int cmd, u ...@@ -208,20 +204,58 @@ static int fop_ioctl(struct inode *inode, struct file *file, unsigned int cmd, u
{ {
static struct watchdog_info ident = static struct watchdog_info ident =
{ {
.options = WDIOF_MAGICCLOSE, .options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE,
.firmware_version = 1, .firmware_version = 1,
.identity = "ALiM7101" .identity = "ALiM7101",
}; };
switch(cmd) switch(cmd)
{ {
case WDIOC_GETSUPPORT: case WDIOC_GETSUPPORT:
return copy_to_user((struct watchdog_info *)arg, &ident, sizeof(ident))?-EFAULT:0; return copy_to_user((struct watchdog_info *)arg, &ident, sizeof(ident))?-EFAULT:0;
case WDIOC_GETSTATUS:
case WDIOC_GETBOOTSTATUS:
return put_user(0, (int *)arg);
case WDIOC_KEEPALIVE: case WDIOC_KEEPALIVE:
next_heartbeat = jiffies + WDT_HEARTBEAT; wdt_keepalive();
return 0; return 0;
case WDIOC_SETOPTIONS:
{
int new_options, retval = -EINVAL;
if(get_user(new_options, (int *)arg))
return -EFAULT;
if(new_options & WDIOS_DISABLECARD) {
wdt_turnoff();
retval = 0;
}
if(new_options & WDIOS_ENABLECARD) {
wdt_startup();
retval = 0;
}
return retval;
}
case WDIOC_SETTIMEOUT:
{
int new_timeout;
if(get_user(new_timeout, (int *)arg))
return -EFAULT;
if(new_timeout < 1 || new_timeout > 3600) /* arbitrary upper limit */
return -EINVAL;
timeout = new_timeout;
wdt_keepalive();
/* Fall through */
}
case WDIOC_GETTIMEOUT:
return put_user(timeout, (int *)arg);
default: default:
return -ENOTTY; return -ENOIOCTLCMD;
} }
} }
...@@ -231,13 +265,13 @@ static struct file_operations wdt_fops = { ...@@ -231,13 +265,13 @@ static struct file_operations wdt_fops = {
.write= fop_write, .write= fop_write,
.open= fop_open, .open= fop_open,
.release= fop_close, .release= fop_close,
.ioctl= fop_ioctl .ioctl= fop_ioctl,
}; };
static struct miscdevice wdt_miscdev = { static struct miscdevice wdt_miscdev = {
.minor=WATCHDOG_MINOR, .minor=WATCHDOG_MINOR,
.name="watchdog", .name="watchdog",
.fops=&wdt_fops .fops=&wdt_fops,
}; };
/* /*
...@@ -256,21 +290,21 @@ static int wdt_notify_sys(struct notifier_block *this, unsigned long code, void ...@@ -256,21 +290,21 @@ static int wdt_notify_sys(struct notifier_block *this, unsigned long code, void
* reboot with no heartbeat * reboot with no heartbeat
*/ */
wdt_change(WDT_ENABLE); wdt_change(WDT_ENABLE);
printk(KERN_INFO OUR_NAME ": Watchdog timer is now enabled with no heartbeat - should reboot in ~1 second.\n"); printk(KERN_INFO PFX "Watchdog timer is now enabled with no heartbeat - should reboot in ~1 second.\n");
} }
return NOTIFY_DONE; return NOTIFY_DONE;
} }
/* /*
* The WDT needs to learn about soft shutdowns in order to * The WDT needs to learn about soft shutdowns in order to
* turn the timebomb registers off. * turn the timebomb registers off.
*/ */
static struct notifier_block wdt_notifier= static struct notifier_block wdt_notifier=
{ {
.notifier_call = wdt_notify_sys, .notifier_call = wdt_notify_sys,
.next = 0, .next = 0,
.priority = 0 .priority = 0,
}; };
static void __exit alim7101_wdt_unload(void) static void __exit alim7101_wdt_unload(void)
...@@ -287,10 +321,10 @@ static int __init alim7101_wdt_init(void) ...@@ -287,10 +321,10 @@ static int __init alim7101_wdt_init(void)
struct pci_dev *ali1543_south; struct pci_dev *ali1543_south;
char tmp; char tmp;
printk(KERN_INFO OUR_NAME ": Steve Hill <steve@navaho.co.uk>.\n"); printk(KERN_INFO PFX "Steve Hill <steve@navaho.co.uk>.\n");
alim7101_pmu = pci_find_device(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M7101,NULL); alim7101_pmu = pci_find_device(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M7101,NULL);
if (!alim7101_pmu) { if (!alim7101_pmu) {
printk(KERN_INFO OUR_NAME ": ALi M7101 PMU not present - WDT not set\n"); printk(KERN_INFO PFX "ALi M7101 PMU not present - WDT not set\n");
return -EBUSY; return -EBUSY;
} }
...@@ -299,35 +333,53 @@ static int __init alim7101_wdt_init(void) ...@@ -299,35 +333,53 @@ static int __init alim7101_wdt_init(void)
ali1543_south = pci_find_device(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M1533, NULL); ali1543_south = pci_find_device(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M1533, NULL);
if (!ali1543_south) { if (!ali1543_south) {
printk(KERN_INFO OUR_NAME ": ALi 1543 South-Bridge not present - WDT not set\n"); printk(KERN_INFO PFX "ALi 1543 South-Bridge not present - WDT not set\n");
return -EBUSY; return -EBUSY;
} }
pci_read_config_byte(ali1543_south, 0x5e, &tmp); pci_read_config_byte(ali1543_south, 0x5e, &tmp);
if ((tmp & 0x1e) != 0x12) { if ((tmp & 0x1e) != 0x12) {
printk(KERN_INFO OUR_NAME ": ALi 1543 South-Bridge does not have the correct revision number (???1001?) - WDT not set\n"); printk(KERN_INFO PFX "ALi 1543 South-Bridge does not have the correct revision number (???1001?) - WDT not set\n");
return -EBUSY; return -EBUSY;
} }
if(timeout < 1 || timeout > 3600) /* arbitrary upper limit */
{
timeout = WATCHDOG_TIMEOUT;
printk(KERN_INFO PFX "timeout value must be 1<=x<=3600, using %d\n",
timeout);
}
init_timer(&timer); init_timer(&timer);
timer.function = wdt_timer_ping; timer.function = wdt_timer_ping;
timer.data = 1; timer.data = 1;
rc = misc_register(&wdt_miscdev); rc = misc_register(&wdt_miscdev);
if (rc) if (rc) {
return rc; printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
wdt_miscdev.minor, rc);
goto err_out;
}
rc = register_reboot_notifier(&wdt_notifier); rc = register_reboot_notifier(&wdt_notifier);
if (rc) { if (rc) {
misc_deregister(&wdt_miscdev); printk(KERN_ERR PFX "cannot register reboot notifier (err=%d)\n",
return rc; rc);
goto err_out_miscdev;
} }
printk(KERN_INFO OUR_NAME ": WDT driver for ALi M7101 initialised.\n"); printk(KERN_INFO PFX "WDT driver for ALi M7101 initialised. timeout=%d sec (nowayout=%d)\n",
timeout, nowayout);
return 0; return 0;
err_out_miscdev:
misc_deregister(&wdt_miscdev);
err_out:
return rc;
} }
module_init(alim7101_wdt_init); module_init(alim7101_wdt_init);
module_exit(alim7101_wdt_unload); module_exit(alim7101_wdt_unload);
MODULE_AUTHOR("Steve Hill"); MODULE_AUTHOR("Steve Hill");
MODULE_DESCRIPTION("ALi M7101 PMU Computer Watchdog Timer driver");
MODULE_LICENSE("GPL"); MODULE_LICENSE("GPL");
/* /*
* AMD Elan SC520 processor Watchdog Timer driver for Linux 2.4.x * AMD Elan SC520 processor Watchdog Timer driver
* *
* Based on acquirewdt.c by Alan Cox, * Based on acquirewdt.c by Alan Cox,
* and sbc60xxwdt.c by Jakob Oestergaard <jakob@ostenfeld.dk> * and sbc60xxwdt.c by Jakob Oestergaard <jakob@unthought.net>
* *
* This program is free software; you can redistribute it and/or * This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License * modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version * as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version. * 2 of the License, or (at your option) any later version.
* *
* The authors do NOT admit liability nor provide warranty for * The authors do NOT admit liability nor provide warranty for
* any of this software. This material is provided "AS-IS" in * any of this software. This material is provided "AS-IS" in
* the hope that it may be useful for others. * the hope that it may be useful for others.
* *
* (c) Copyright 2001 Scott Jennings <linuxdrivers@oro.net> * (c) Copyright 2001 Scott Jennings <linuxdrivers@oro.net>
* 9/27 - 2001 [Initial release] * 9/27 - 2001 [Initial release]
* *
* Additional fixes Alan Cox * Additional fixes Alan Cox
* - Fixed formatting * - Fixed formatting
* - Removed debug printks * - Removed debug printks
...@@ -24,20 +24,21 @@ ...@@ -24,20 +24,21 @@
* - Used ioremap/writew/readw * - Used ioremap/writew/readw
* - Added NOWAYOUT support * - Added NOWAYOUT support
* *
* Theory of operation: * 4/12 - 2002 Changes by Rob Radez <rob@osinvestor.com>
* A Watchdog Timer (WDT) is a hardware circuit that can * - Change comments
* reset the computer system in case of a software fault. * - Eliminate fop_llseek
* You probably knew that already. * - Change CONFIG_WATCHDOG_NOWAYOUT semantics
* * - Add KERN_* tags to printks
* Usually a userspace daemon will notify the kernel WDT driver * - fix possible wdt_is_open race
* via the /proc/watchdog special device file that userspace is * - Report proper capabilities in watchdog_info
* still alive, at regular intervals. When such a notification * - Add WDIOC_{GETSTATUS, GETBOOTSTATUS, SETTIMEOUT,
* occurs, the driver will usually tell the hardware watchdog * GETTIMEOUT, SETOPTIONS} ioctls
* that everything is in order, and that the watchdog should wait * 09/8 - 2003 Changes by Wim Van Sebroeck <wim@iguana.be>
* for yet another little while to reset the system. * - cleanup of trailing spaces
* If userspace fails (RAM error, kernel bug, whatever), the * - added extra printk's for startup problems
* notifications cease to occur, and the hardware watchdog will * - use module_param
* reset the system (causing a reboot) after the timeout occurs. * - made timeout (the emulated heartbeat) a module_param
* - made the keepalive ping an internal subroutine
* *
* This WDT driver is different from most other Linux WDT * This WDT driver is different from most other Linux WDT
* drivers in that the driver will ping the watchdog by itself, * drivers in that the driver will ping the watchdog by itself,
...@@ -77,7 +78,10 @@ ...@@ -77,7 +78,10 @@
* char to /dev/watchdog every 30 seconds. * char to /dev/watchdog every 30 seconds.
*/ */
#define WDT_HEARTBEAT (HZ * 30) #define WATCHDOG_TIMEOUT 30 /* 30 sec default timeout */
static int timeout = WATCHDOG_TIMEOUT; /* in seconds, will be multiplied by HZ to get seconds to wait for a ping */
module_param(timeout, int, 0);
MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds. (1<=timeout<=3600, default=" __MODULE_STRING(WATCHDOG_TIMEOUT) ")");
/* /*
* AMD Elan SC520 timeout value is 492us times a power of 2 (0-7) * AMD Elan SC520 timeout value is 492us times a power of 2 (0-7)
...@@ -95,6 +99,7 @@ ...@@ -95,6 +99,7 @@
#define WDT_WRST_ENB 0x4000 /* [14] Watchdog Timer Reset Enable */ #define WDT_WRST_ENB 0x4000 /* [14] Watchdog Timer Reset Enable */
#define OUR_NAME "sc520_wdt" #define OUR_NAME "sc520_wdt"
#define PFX OUR_NAME ": "
#define WRT_DOG(data) *wdtmrctl=data #define WRT_DOG(data) *wdtmrctl=data
...@@ -104,7 +109,8 @@ static void wdt_timer_ping(unsigned long); ...@@ -104,7 +109,8 @@ static void wdt_timer_ping(unsigned long);
static struct timer_list timer; static struct timer_list timer;
static unsigned long next_heartbeat; static unsigned long next_heartbeat;
static unsigned long wdt_is_open; static unsigned long wdt_is_open;
static int wdt_expect_close; static char wdt_expect_close;
static spinlock_t wdt_spinlock;
#ifdef CONFIG_WATCHDOG_NOWAYOUT #ifdef CONFIG_WATCHDOG_NOWAYOUT
static int nowayout = 1; static int nowayout = 1;
...@@ -115,7 +121,6 @@ static int nowayout = 0; ...@@ -115,7 +121,6 @@ static int nowayout = 0;
module_param(nowayout, int, 0); module_param(nowayout, int, 0);
MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=CONFIG_WATCHDOG_NOWAYOUT)"); MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=CONFIG_WATCHDOG_NOWAYOUT)");
static spinlock_t wdt_spinlock;
/* /*
* Whack the dog * Whack the dog
*/ */
...@@ -123,9 +128,9 @@ static spinlock_t wdt_spinlock; ...@@ -123,9 +128,9 @@ static spinlock_t wdt_spinlock;
static void wdt_timer_ping(unsigned long data) static void wdt_timer_ping(unsigned long data)
{ {
/* If we got a heartbeat pulse within the WDT_US_INTERVAL /* If we got a heartbeat pulse within the WDT_US_INTERVAL
* we agree to ping the WDT * we agree to ping the WDT
*/ */
if(time_before(jiffies, next_heartbeat)) if(time_before(jiffies, next_heartbeat))
{ {
/* Ping the WDT */ /* Ping the WDT */
spin_lock(&wdt_spinlock); spin_lock(&wdt_spinlock);
...@@ -137,11 +142,11 @@ static void wdt_timer_ping(unsigned long data) ...@@ -137,11 +142,11 @@ static void wdt_timer_ping(unsigned long data)
timer.expires = jiffies + WDT_INTERVAL; timer.expires = jiffies + WDT_INTERVAL;
add_timer(&timer); add_timer(&timer);
} else { } else {
printk(OUR_NAME ": Heartbeat lost! Will not ping the watchdog\n"); printk(KERN_WARNING PFX "Heartbeat lost! Will not ping the watchdog\n");
} }
} }
/* /*
* Utility routines * Utility routines
*/ */
...@@ -165,14 +170,14 @@ static void wdt_config(int writeval) ...@@ -165,14 +170,14 @@ static void wdt_config(int writeval)
static void wdt_startup(void) static void wdt_startup(void)
{ {
next_heartbeat = jiffies + WDT_HEARTBEAT; next_heartbeat = jiffies + (timeout * HZ);
/* Start the timer */ /* Start the timer */
timer.expires = jiffies + WDT_INTERVAL; timer.expires = jiffies + WDT_INTERVAL;
add_timer(&timer); add_timer(&timer);
wdt_config(WDT_ENB | WDT_WRST_ENB | TIMEOUT_EXPONENT); wdt_config(WDT_ENB | WDT_WRST_ENB | TIMEOUT_EXPONENT);
printk(OUR_NAME ": Watchdog timer is now enabled.\n"); printk(KERN_INFO PFX "Watchdog timer is now enabled.\n");
} }
static void wdt_turnoff(void) static void wdt_turnoff(void)
...@@ -181,10 +186,15 @@ static void wdt_turnoff(void) ...@@ -181,10 +186,15 @@ static void wdt_turnoff(void)
/* Stop the timer */ /* Stop the timer */
del_timer(&timer); del_timer(&timer);
wdt_config(0); wdt_config(0);
printk(OUR_NAME ": Watchdog timer is now disabled...\n"); printk(KERN_INFO PFX "Watchdog timer is now disabled...\n");
} }
} }
static void wdt_keepalive(void)
{
/* user land ping */
next_heartbeat = jiffies + (timeout * HZ);
}
/* /*
* /dev/watchdog handling * /dev/watchdog handling
...@@ -196,62 +206,56 @@ static ssize_t fop_write(struct file * file, const char * buf, size_t count, lof ...@@ -196,62 +206,56 @@ static ssize_t fop_write(struct file * file, const char * buf, size_t count, lof
if(ppos != &file->f_pos) if(ppos != &file->f_pos)
return -ESPIPE; return -ESPIPE;
/* See if we got the magic character */ /* See if we got the magic character 'V' and reload the timer */
if(count) if(count)
{ {
size_t ofs; if (!nowayout)
{
/* note: just in case someone wrote the magic character size_t ofs;
* five months ago... */
wdt_expect_close = 0; /* note: just in case someone wrote the magic character
* five months ago... */
/* now scan */ wdt_expect_close = 0;
for(ofs = 0; ofs != count; ofs++) {
char c; /* now scan */
if (get_user(c, buf + ofs)) for(ofs = 0; ofs != count; ofs++) {
return -EFAULT; char c;
if(c == 'V') if (get_user(c, buf + ofs))
wdt_expect_close = 1; return -EFAULT;
if(c == 'V')
wdt_expect_close = 42;
}
} }
/* Well, anyhow someone wrote to us, we should return that favour */ /* Well, anyhow someone wrote to us, we should return that favour */
next_heartbeat = jiffies + WDT_HEARTBEAT; wdt_keepalive();
return 1;
} }
return 0; return count;
} }
static int fop_open(struct inode * inode, struct file * file) static int fop_open(struct inode * inode, struct file * file)
{ {
switch(minor(inode->i_rdev)) /* Just in case we're already talking to someone... */
{ if(test_and_set_bit(0, &wdt_is_open))
case WATCHDOG_MINOR: return -EBUSY;
/* Just in case we're already talking to someone... */ if (nowayout)
if(test_and_set_bit(0, &wdt_is_open)) __module_get(THIS_MODULE);
return -EBUSY;
/* Good, fire up the show */ /* Good, fire up the show */
wdt_startup(); wdt_startup();
if (nowayout) return 0;
__module_get(THIS_MODULE);
return 0;
default:
return -ENODEV;
}
} }
static int fop_close(struct inode * inode, struct file * file) static int fop_close(struct inode * inode, struct file * file)
{ {
if(minor(inode->i_rdev) == WATCHDOG_MINOR) if(wdt_expect_close == 42)
{ wdt_turnoff();
if(wdt_expect_close) else {
wdt_turnoff(); del_timer(&timer);
else { printk(KERN_CRIT PFX "device file closed unexpectedly. Will not stop the WDT!\n");
del_timer(&timer);
printk(OUR_NAME ": device file closed unexpectedly. Will not stop the WDT!\n");
}
} }
clear_bit(0, &wdt_is_open); clear_bit(0, &wdt_is_open);
wdt_expect_close = 0;
return 0; return 0;
} }
...@@ -260,20 +264,58 @@ static int fop_ioctl(struct inode *inode, struct file *file, unsigned int cmd, ...@@ -260,20 +264,58 @@ static int fop_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
{ {
static struct watchdog_info ident= static struct watchdog_info ident=
{ {
.options = WDIOF_MAGICCLOSE, .options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE,
.firmware_version = 1, .firmware_version = 1,
.identity = "SC520" .identity = "SC520",
}; };
switch(cmd) switch(cmd)
{ {
default: default:
return -ENOIOCTLCMD; return -ENOIOCTLCMD;
case WDIOC_GETSUPPORT: case WDIOC_GETSUPPORT:
return copy_to_user((struct watchdog_info *)arg, &ident, sizeof(ident))?-EFAULT:0; return copy_to_user((struct watchdog_info *)arg, &ident, sizeof(ident))?-EFAULT:0;
case WDIOC_GETSTATUS:
case WDIOC_GETBOOTSTATUS:
return put_user(0, (int *)arg);
case WDIOC_KEEPALIVE: case WDIOC_KEEPALIVE:
next_heartbeat = jiffies + WDT_HEARTBEAT; wdt_keepalive();
return 0; return 0;
case WDIOC_SETOPTIONS:
{
int new_options, retval = -EINVAL;
if(get_user(new_options, (int *)arg))
return -EFAULT;
if(new_options & WDIOS_DISABLECARD) {
wdt_turnoff();
retval = 0;
}
if(new_options & WDIOS_ENABLECARD) {
wdt_startup();
retval = 0;
}
return retval;
}
case WDIOC_SETTIMEOUT:
{
int new_timeout;
if(get_user(new_timeout, (int *)arg))
return -EFAULT;
if(new_timeout < 1 || new_timeout > 3600) /* arbitrary upper limit */
return -EINVAL;
timeout = new_timeout;
wdt_keepalive();
/* Fall through */
}
case WDIOC_GETTIMEOUT:
return put_user(timeout, (int *)arg);
} }
} }
...@@ -283,13 +325,13 @@ static struct file_operations wdt_fops = { ...@@ -283,13 +325,13 @@ static struct file_operations wdt_fops = {
.write = fop_write, .write = fop_write,
.open = fop_open, .open = fop_open,
.release = fop_close, .release = fop_close,
.ioctl = fop_ioctl .ioctl = fop_ioctl,
}; };
static struct miscdevice wdt_miscdev = { static struct miscdevice wdt_miscdev = {
.minor = WATCHDOG_MINOR, .minor = WATCHDOG_MINOR,
.name = "watchdog", .name = "watchdog",
.fops = &wdt_fops .fops = &wdt_fops,
}; };
/* /*
...@@ -299,21 +341,21 @@ static struct miscdevice wdt_miscdev = { ...@@ -299,21 +341,21 @@ static struct miscdevice wdt_miscdev = {
static int wdt_notify_sys(struct notifier_block *this, unsigned long code, static int wdt_notify_sys(struct notifier_block *this, unsigned long code,
void *unused) void *unused)
{ {
if(code==SYS_DOWN || code==SYS_HALT) if(code==SYS_DOWN || code==SYS_HALT)
wdt_turnoff(); wdt_turnoff();
return NOTIFY_DONE; return NOTIFY_DONE;
} }
/* /*
* The WDT needs to learn about soft shutdowns in order to * The WDT needs to learn about soft shutdowns in order to
* turn the timebomb registers off. * turn the timebomb registers off.
*/ */
static struct notifier_block wdt_notifier= static struct notifier_block wdt_notifier=
{ {
.notifier_call = wdt_notify_sys, .notifier_call = wdt_notify_sys,
.next = NULL, .next = NULL,
.priority = 0 .priority = 0,
}; };
static void __exit sc520_wdt_unload(void) static void __exit sc520_wdt_unload(void)
...@@ -333,27 +375,42 @@ static int __init sc520_wdt_init(void) ...@@ -333,27 +375,42 @@ static int __init sc520_wdt_init(void)
spin_lock_init(&wdt_spinlock); spin_lock_init(&wdt_spinlock);
if(timeout < 1 || timeout > 3600) /* arbitrary upper limit */
{
timeout = WATCHDOG_TIMEOUT;
printk(KERN_INFO PFX "timeout value must be 1<=x<=3600, using %d\n",
timeout);
}
init_timer(&timer); init_timer(&timer);
timer.function = wdt_timer_ping; timer.function = wdt_timer_ping;
timer.data = 0; timer.data = 0;
rc = misc_register(&wdt_miscdev); rc = misc_register(&wdt_miscdev);
if (rc) if (rc)
{
printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
wdt_miscdev.minor, rc);
goto err_out_region2; goto err_out_region2;
}
rc = register_reboot_notifier(&wdt_notifier); rc = register_reboot_notifier(&wdt_notifier);
if (rc) if (rc)
{
printk(KERN_ERR PFX "cannot register reboot notifier (err=%d)\n",
rc);
goto err_out_miscdev; goto err_out_miscdev;
}
/* get the Base Address Register */ /* get the Base Address Register */
cbar = inl_p(0xfffc); cbar = inl_p(0xfffc);
printk(OUR_NAME ": CBAR: 0x%08lx\n", cbar); printk(KERN_INFO PFX "CBAR: 0x%08lx\n", cbar);
/* check if MMCR aliasing bit is set */ /* check if MMCR aliasing bit is set */
if (cbar & 0x80000000) { if (cbar & 0x80000000) {
printk(OUR_NAME ": MMCR Aliasing enabled.\n"); printk(KERN_INFO PFX "MMCR Aliasing enabled.\n");
wdtmrctl = (__u16 *)(cbar & 0x3fffffff); wdtmrctl = (__u16 *)(cbar & 0x3fffffff);
} else { } else {
printk(OUR_NAME "!!! WARNING !!!\n" printk(KERN_INFO PFX "!!! WARNING !!!\n"
"\t MMCR Aliasing found NOT enabled!\n" "\t MMCR Aliasing found NOT enabled!\n"
"\t Using default value of: %p\n" "\t Using default value of: %p\n"
"\t This has not been tested!\n" "\t This has not been tested!\n"
...@@ -366,7 +423,8 @@ static int __init sc520_wdt_init(void) ...@@ -366,7 +423,8 @@ static int __init sc520_wdt_init(void)
wdtmrctl = (__u16 *)((char *)wdtmrctl + OFFS_WDTMRCTL); wdtmrctl = (__u16 *)((char *)wdtmrctl + OFFS_WDTMRCTL);
wdtmrctl = ioremap((unsigned long)wdtmrctl, 2); wdtmrctl = ioremap((unsigned long)wdtmrctl, 2);
printk(KERN_INFO OUR_NAME ": WDT driver for SC520 initialised.\n"); printk(KERN_INFO PFX "WDT driver for SC520 initialised. timeout=%d sec (nowayout=%d)\n",
timeout,nowayout);
return 0; return 0;
......
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