Commit 0df01764 authored by Wim Van Sebroeck's avatar Wim Van Sebroeck

[WATCHDOG] sc520_wdt.c patch

cleanup comments and trailing spaces
add KERN_* tags to printks
added extra printk's to report what problem occured
parent d2473081
/* /*
* 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 +24,15 @@ ...@@ -24,20 +24,15 @@
* - 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 * 09/8 - 2003 Changes by Wim Van Sebroeck <wim@iguana.be>
* via the /proc/watchdog special device file that userspace is * - cleanup of trailing spaces
* still alive, at regular intervals. When such a notification * - added extra printk's for startup problems
* occurs, the driver will usually tell the hardware watchdog * - use module_param
* 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,
...@@ -95,6 +90,7 @@ ...@@ -95,6 +90,7 @@
#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
...@@ -123,9 +119,9 @@ static spinlock_t wdt_spinlock; ...@@ -123,9 +119,9 @@ 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 +133,11 @@ static void wdt_timer_ping(unsigned long data) ...@@ -137,11 +133,11 @@ 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
*/ */
...@@ -168,11 +164,11 @@ static void wdt_startup(void) ...@@ -168,11 +164,11 @@ static void wdt_startup(void)
next_heartbeat = jiffies + WDT_HEARTBEAT; next_heartbeat = jiffies + WDT_HEARTBEAT;
/* 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)
...@@ -181,7 +177,7 @@ static void wdt_turnoff(void) ...@@ -181,7 +177,7 @@ 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");
} }
} }
...@@ -197,7 +193,7 @@ static ssize_t fop_write(struct file * file, const char * buf, size_t count, lof ...@@ -197,7 +193,7 @@ static ssize_t fop_write(struct file * file, const char * buf, size_t count, lof
return -ESPIPE; return -ESPIPE;
/* See if we got the magic character */ /* See if we got the magic character */
if(count) if(count)
{ {
size_t ofs; size_t ofs;
...@@ -223,7 +219,7 @@ static ssize_t fop_write(struct file * file, const char * buf, size_t count, lof ...@@ -223,7 +219,7 @@ static ssize_t fop_write(struct file * file, const char * buf, size_t count, lof
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)) switch(minor(inode->i_rdev))
{ {
case WATCHDOG_MINOR: case WATCHDOG_MINOR:
/* Just in case we're already talking to someone... */ /* Just in case we're already talking to someone... */
...@@ -242,13 +238,13 @@ static int fop_open(struct inode * inode, struct file * file) ...@@ -242,13 +238,13 @@ 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(minor(inode->i_rdev) == WATCHDOG_MINOR) if(minor(inode->i_rdev) == WATCHDOG_MINOR)
{ {
if(wdt_expect_close) if(wdt_expect_close)
wdt_turnoff(); wdt_turnoff();
else { else {
del_timer(&timer); del_timer(&timer);
printk(OUR_NAME ": device file closed unexpectedly. Will not stop the WDT!\n"); 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);
...@@ -262,9 +258,9 @@ static int fop_ioctl(struct inode *inode, struct file *file, unsigned int cmd, ...@@ -262,9 +258,9 @@ static int fop_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
{ {
.options = WDIOF_MAGICCLOSE, .options = WDIOF_MAGICCLOSE,
.firmware_version = 1, .firmware_version = 1,
.identity = "SC520" .identity = "SC520",
}; };
switch(cmd) switch(cmd)
{ {
default: default:
...@@ -283,13 +279,13 @@ static struct file_operations wdt_fops = { ...@@ -283,13 +279,13 @@ 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 +295,21 @@ static struct miscdevice wdt_miscdev = { ...@@ -299,21 +295,21 @@ 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)
...@@ -339,21 +335,29 @@ static int __init sc520_wdt_init(void) ...@@ -339,21 +335,29 @@ static int __init sc520_wdt_init(void)
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 +370,7 @@ static int __init sc520_wdt_init(void) ...@@ -366,7 +370,7 @@ 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.\n");
return 0; return 0;
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment