mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-19 02:04:19 +08:00
33c050c586
Add support for PNX833x watchdog timer. Signed-off-by: Daniel Laird <daniel.j.laird@nxp.com> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
283 lines
7.1 KiB
C
283 lines
7.1 KiB
C
/*
|
|
* PNX833x Hardware Watchdog Driver
|
|
* Copyright 2008 NXP Semiconductors
|
|
* Daniel Laird <daniel.j.laird@nxp.com>
|
|
* Andre McCurdy <andre.mccurdy@nxp.com>
|
|
*
|
|
* Heavily based upon - IndyDog 0.3
|
|
* A Hardware Watchdog Device for SGI IP22
|
|
*
|
|
* (c) Copyright 2002 Guido Guenther <agx@sigxcpu.org>, All Rights Reserved.
|
|
*
|
|
* 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.
|
|
*
|
|
* based on softdog.c by Alan Cox <alan@redhat.com>
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/moduleparam.h>
|
|
#include <linux/types.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/fs.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/miscdevice.h>
|
|
#include <linux/watchdog.h>
|
|
#include <linux/notifier.h>
|
|
#include <linux/reboot.h>
|
|
#include <linux/init.h>
|
|
#include <asm/mach-pnx833x/pnx833x.h>
|
|
|
|
#define PFX "pnx833x: "
|
|
#define WATCHDOG_TIMEOUT 30 /* 30 sec Maximum timeout */
|
|
#define WATCHDOG_COUNT_FREQUENCY 68000000U /* Watchdog counts at 68MHZ. */
|
|
|
|
/** CONFIG block */
|
|
#define PNX833X_CONFIG (0x07000U)
|
|
#define PNX833X_CONFIG_CPU_WATCHDOG (0x54)
|
|
#define PNX833X_CONFIG_CPU_WATCHDOG_COMPARE (0x58)
|
|
#define PNX833X_CONFIG_CPU_COUNTERS_CONTROL (0x1c)
|
|
|
|
/** RESET block */
|
|
#define PNX833X_RESET (0x08000U)
|
|
#define PNX833X_RESET_CONFIG (0x08)
|
|
|
|
static int pnx833x_wdt_alive;
|
|
|
|
/* Set default timeout in MHZ.*/
|
|
static int pnx833x_wdt_timeout = (WATCHDOG_TIMEOUT * WATCHDOG_COUNT_FREQUENCY);
|
|
module_param(pnx833x_wdt_timeout, int, 0);
|
|
MODULE_PARM_DESC(timeout, "Watchdog timeout in Mhz. (68Mhz clock), default="
|
|
__MODULE_STRING(pnx833x_wdt_timeout) "(30 seconds).");
|
|
|
|
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) ")");
|
|
|
|
static int start_enabled = 1;
|
|
module_param(start_enabled, int, 0);
|
|
MODULE_PARM_DESC(start_enabled, "Watchdog is started on module insertion "
|
|
"(default=" __MODULE_STRING(start_enabled) ")");
|
|
|
|
static void pnx833x_wdt_start(void)
|
|
{
|
|
/* Enable watchdog causing reset. */
|
|
PNX833X_REG(PNX833X_RESET + PNX833X_RESET_CONFIG) |= 0x1;
|
|
/* Set timeout.*/
|
|
PNX833X_REG(PNX833X_CONFIG +
|
|
PNX833X_CONFIG_CPU_WATCHDOG_COMPARE) = pnx833x_wdt_timeout;
|
|
/* Enable watchdog. */
|
|
PNX833X_REG(PNX833X_CONFIG +
|
|
PNX833X_CONFIG_CPU_COUNTERS_CONTROL) |= 0x1;
|
|
|
|
printk(KERN_INFO PFX "Started watchdog timer.\n");
|
|
}
|
|
|
|
static void pnx833x_wdt_stop(void)
|
|
{
|
|
/* Disable watchdog causing reset. */
|
|
PNX833X_REG(PNX833X_RESET + PNX833X_CONFIG) &= 0xFFFFFFFE;
|
|
/* Disable watchdog.*/
|
|
PNX833X_REG(PNX833X_CONFIG +
|
|
PNX833X_CONFIG_CPU_COUNTERS_CONTROL) &= 0xFFFFFFFE;
|
|
|
|
printk(KERN_INFO PFX "Stopped watchdog timer.\n");
|
|
}
|
|
|
|
static void pnx833x_wdt_ping(void)
|
|
{
|
|
PNX833X_REG(PNX833X_CONFIG +
|
|
PNX833X_CONFIG_CPU_WATCHDOG_COMPARE) = pnx833x_wdt_timeout;
|
|
}
|
|
|
|
/*
|
|
* Allow only one person to hold it open
|
|
*/
|
|
static int pnx833x_wdt_open(struct inode *inode, struct file *file)
|
|
{
|
|
if (test_and_set_bit(0, &pnx833x_wdt_alive))
|
|
return -EBUSY;
|
|
|
|
if (nowayout)
|
|
__module_get(THIS_MODULE);
|
|
|
|
/* Activate timer */
|
|
if (!start_enabled)
|
|
pnx833x_wdt_start();
|
|
|
|
pnx833x_wdt_ping();
|
|
|
|
printk(KERN_INFO "Started watchdog timer.\n");
|
|
|
|
return nonseekable_open(inode, file);
|
|
}
|
|
|
|
static int pnx833x_wdt_release(struct inode *inode, struct file *file)
|
|
{
|
|
/* Shut off the timer.
|
|
* Lock it in if it's a module and we defined ...NOWAYOUT */
|
|
if (!nowayout)
|
|
pnx833x_wdt_stop(); /* Turn the WDT off */
|
|
|
|
clear_bit(0, &pnx833x_wdt_alive);
|
|
return 0;
|
|
}
|
|
|
|
static ssize_t pnx833x_wdt_write(struct file *file, const char *data, size_t len, loff_t *ppos)
|
|
{
|
|
/* Refresh the timer. */
|
|
if (len)
|
|
pnx833x_wdt_ping();
|
|
|
|
return len;
|
|
}
|
|
|
|
static long pnx833x_wdt_ioctl(struct file *file, unsigned int cmd,
|
|
unsigned long arg)
|
|
{
|
|
int options, new_timeout = 0;
|
|
uint32_t timeout, timeout_left = 0;
|
|
|
|
static struct watchdog_info ident = {
|
|
.options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT,
|
|
.firmware_version = 0,
|
|
.identity = "Hardware Watchdog for PNX833x",
|
|
};
|
|
|
|
switch (cmd) {
|
|
default:
|
|
return -ENOTTY;
|
|
|
|
case WDIOC_GETSUPPORT:
|
|
if (copy_to_user((struct watchdog_info *)arg,
|
|
&ident, sizeof(ident)))
|
|
return -EFAULT;
|
|
return 0;
|
|
|
|
case WDIOC_GETSTATUS:
|
|
case WDIOC_GETBOOTSTATUS:
|
|
return put_user(0, (int *)arg);
|
|
|
|
case WDIOC_SETOPTIONS:
|
|
if (get_user(options, (int *)arg))
|
|
return -EFAULT;
|
|
|
|
if (options & WDIOS_DISABLECARD)
|
|
pnx833x_wdt_stop();
|
|
|
|
if (options & WDIOS_ENABLECARD)
|
|
pnx833x_wdt_start();
|
|
|
|
return 0;
|
|
|
|
case WDIOC_KEEPALIVE:
|
|
pnx833x_wdt_ping();
|
|
return 0;
|
|
|
|
case WDIOC_SETTIMEOUT:
|
|
{
|
|
if (get_user(new_timeout, (int *)arg))
|
|
return -EFAULT;
|
|
|
|
pnx833x_wdt_timeout = new_timeout;
|
|
PNX833X_REG(PNX833X_CONFIG +
|
|
PNX833X_CONFIG_CPU_WATCHDOG_COMPARE) = new_timeout;
|
|
return put_user(new_timeout, (int *)arg);
|
|
}
|
|
|
|
case WDIOC_GETTIMEOUT:
|
|
timeout = PNX833X_REG(PNX833X_CONFIG +
|
|
PNX833X_CONFIG_CPU_WATCHDOG_COMPARE);
|
|
return put_user(timeout, (int *)arg);
|
|
|
|
case WDIOC_GETTIMELEFT:
|
|
timeout_left = PNX833X_REG(PNX833X_CONFIG +
|
|
PNX833X_CONFIG_CPU_WATCHDOG);
|
|
return put_user(timeout_left, (int *)arg);
|
|
|
|
}
|
|
}
|
|
|
|
static int pnx833x_wdt_notify_sys(struct notifier_block *this,
|
|
unsigned long code, void *unused)
|
|
{
|
|
if (code == SYS_DOWN || code == SYS_HALT)
|
|
pnx833x_wdt_stop(); /* Turn the WDT off */
|
|
|
|
return NOTIFY_DONE;
|
|
}
|
|
|
|
static const struct file_operations pnx833x_wdt_fops = {
|
|
.owner = THIS_MODULE,
|
|
.llseek = no_llseek,
|
|
.write = pnx833x_wdt_write,
|
|
.unlocked_ioctl = pnx833x_wdt_ioctl,
|
|
.open = pnx833x_wdt_open,
|
|
.release = pnx833x_wdt_release,
|
|
};
|
|
|
|
static struct miscdevice pnx833x_wdt_miscdev = {
|
|
.minor = WATCHDOG_MINOR,
|
|
.name = "watchdog",
|
|
.fops = &pnx833x_wdt_fops,
|
|
};
|
|
|
|
static struct notifier_block pnx833x_wdt_notifier = {
|
|
.notifier_call = pnx833x_wdt_notify_sys,
|
|
};
|
|
|
|
static char banner[] __initdata =
|
|
KERN_INFO PFX "Hardware Watchdog Timer for PNX833x: Version 0.1\n";
|
|
|
|
static int __init watchdog_init(void)
|
|
{
|
|
int ret, cause;
|
|
|
|
/* Lets check the reason for the reset.*/
|
|
cause = PNX833X_REG(PNX833X_RESET);
|
|
/*If bit 31 is set then watchdog was cause of reset.*/
|
|
if (cause & 0x80000000) {
|
|
printk(KERN_INFO PFX "The system was previously reset due to "
|
|
"the watchdog firing - please investigate...\n");
|
|
}
|
|
|
|
ret = register_reboot_notifier(&pnx833x_wdt_notifier);
|
|
if (ret) {
|
|
printk(KERN_ERR PFX
|
|
"cannot register reboot notifier (err=%d)\n", ret);
|
|
return ret;
|
|
}
|
|
|
|
ret = misc_register(&pnx833x_wdt_miscdev);
|
|
if (ret) {
|
|
printk(KERN_ERR PFX
|
|
"cannot register miscdev on minor=%d (err=%d)\n",
|
|
WATCHDOG_MINOR, ret);
|
|
unregister_reboot_notifier(&pnx833x_wdt_notifier);
|
|
return ret;
|
|
}
|
|
|
|
printk(banner);
|
|
if (start_enabled)
|
|
pnx833x_wdt_start();
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void __exit watchdog_exit(void)
|
|
{
|
|
misc_deregister(&pnx833x_wdt_miscdev);
|
|
unregister_reboot_notifier(&pnx833x_wdt_notifier);
|
|
}
|
|
|
|
module_init(watchdog_init);
|
|
module_exit(watchdog_exit);
|
|
|
|
MODULE_AUTHOR("Daniel Laird/Andre McCurdy");
|
|
MODULE_DESCRIPTION("Hardware Watchdog Device for PNX833x");
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
|