253 lines
5.9 KiB
C
253 lines
5.9 KiB
C
![]() |
/*
|
||
|
* mv64x60_wdt.c - MV64X60 (Marvell Discovery) watchdog userspace interface
|
||
|
*
|
||
|
* Author: James Chapman <jchapman@katalix.com>
|
||
|
*
|
||
|
* Platform-specific setup code should configure the dog to generate
|
||
|
* interrupt or reset as required. This code only enables/disables
|
||
|
* and services the watchdog.
|
||
|
*
|
||
|
* Derived from mpc8xx_wdt.c, with the following copyright.
|
||
|
*
|
||
|
* 2002 (c) Florian Schirmer <jolt@tuxbox.org> This file is licensed under
|
||
|
* the terms of the GNU General Public License version 2. This program
|
||
|
* is licensed "as is" without any warranty of any kind, whether express
|
||
|
* or implied.
|
||
|
*/
|
||
|
|
||
|
#include <linux/config.h>
|
||
|
#include <linux/fs.h>
|
||
|
#include <linux/init.h>
|
||
|
#include <linux/kernel.h>
|
||
|
#include <linux/miscdevice.h>
|
||
|
#include <linux/module.h>
|
||
|
#include <linux/watchdog.h>
|
||
|
#include <asm/mv64x60.h>
|
||
|
#include <asm/uaccess.h>
|
||
|
#include <asm/io.h>
|
||
|
|
||
|
/* MV64x60 WDC (config) register access definitions */
|
||
|
#define MV64x60_WDC_CTL1_MASK (3 << 24)
|
||
|
#define MV64x60_WDC_CTL1(val) ((val & 3) << 24)
|
||
|
#define MV64x60_WDC_CTL2_MASK (3 << 26)
|
||
|
#define MV64x60_WDC_CTL2(val) ((val & 3) << 26)
|
||
|
|
||
|
/* Flags bits */
|
||
|
#define MV64x60_WDOG_FLAG_OPENED 0
|
||
|
#define MV64x60_WDOG_FLAG_ENABLED 1
|
||
|
|
||
|
static unsigned long wdt_flags;
|
||
|
static int wdt_status;
|
||
|
static void __iomem *mv64x60_regs;
|
||
|
static int mv64x60_wdt_timeout;
|
||
|
|
||
|
static void mv64x60_wdt_reg_write(u32 val)
|
||
|
{
|
||
|
/* Allow write only to CTL1 / CTL2 fields, retaining values in
|
||
|
* other fields.
|
||
|
*/
|
||
|
u32 data = readl(mv64x60_regs + MV64x60_WDT_WDC);
|
||
|
data &= ~(MV64x60_WDC_CTL1_MASK | MV64x60_WDC_CTL2_MASK);
|
||
|
data |= val;
|
||
|
writel(data, mv64x60_regs + MV64x60_WDT_WDC);
|
||
|
}
|
||
|
|
||
|
static void mv64x60_wdt_service(void)
|
||
|
{
|
||
|
/* Write 01 followed by 10 to CTL2 */
|
||
|
mv64x60_wdt_reg_write(MV64x60_WDC_CTL2(0x01));
|
||
|
mv64x60_wdt_reg_write(MV64x60_WDC_CTL2(0x02));
|
||
|
}
|
||
|
|
||
|
static void mv64x60_wdt_handler_disable(void)
|
||
|
{
|
||
|
if (test_and_clear_bit(MV64x60_WDOG_FLAG_ENABLED, &wdt_flags)) {
|
||
|
/* Write 01 followed by 10 to CTL1 */
|
||
|
mv64x60_wdt_reg_write(MV64x60_WDC_CTL1(0x01));
|
||
|
mv64x60_wdt_reg_write(MV64x60_WDC_CTL1(0x02));
|
||
|
printk(KERN_NOTICE "mv64x60_wdt: watchdog deactivated\n");
|
||
|
}
|
||
|
}
|
||
|
|
||
|
static void mv64x60_wdt_handler_enable(void)
|
||
|
{
|
||
|
if (!test_and_set_bit(MV64x60_WDOG_FLAG_ENABLED, &wdt_flags)) {
|
||
|
/* Write 01 followed by 10 to CTL1 */
|
||
|
mv64x60_wdt_reg_write(MV64x60_WDC_CTL1(0x01));
|
||
|
mv64x60_wdt_reg_write(MV64x60_WDC_CTL1(0x02));
|
||
|
printk(KERN_NOTICE "mv64x60_wdt: watchdog activated\n");
|
||
|
}
|
||
|
}
|
||
|
|
||
|
static int mv64x60_wdt_open(struct inode *inode, struct file *file)
|
||
|
{
|
||
|
if (test_and_set_bit(MV64x60_WDOG_FLAG_OPENED, &wdt_flags))
|
||
|
return -EBUSY;
|
||
|
|
||
|
mv64x60_wdt_service();
|
||
|
mv64x60_wdt_handler_enable();
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static int mv64x60_wdt_release(struct inode *inode, struct file *file)
|
||
|
{
|
||
|
mv64x60_wdt_service();
|
||
|
|
||
|
#if !defined(CONFIG_WATCHDOG_NOWAYOUT)
|
||
|
mv64x60_wdt_handler_disable();
|
||
|
#endif
|
||
|
|
||
|
clear_bit(MV64x60_WDOG_FLAG_OPENED, &wdt_flags);
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static ssize_t mv64x60_wdt_write(struct file *file, const char *data,
|
||
|
size_t len, loff_t * ppos)
|
||
|
{
|
||
|
if (*ppos != file->f_pos)
|
||
|
return -ESPIPE;
|
||
|
|
||
|
if (len)
|
||
|
mv64x60_wdt_service();
|
||
|
|
||
|
return len;
|
||
|
}
|
||
|
|
||
|
static int mv64x60_wdt_ioctl(struct inode *inode, struct file *file,
|
||
|
unsigned int cmd, unsigned long arg)
|
||
|
{
|
||
|
int timeout;
|
||
|
static struct watchdog_info info = {
|
||
|
.options = WDIOF_KEEPALIVEPING,
|
||
|
.firmware_version = 0,
|
||
|
.identity = "MV64x60 watchdog",
|
||
|
};
|
||
|
|
||
|
switch (cmd) {
|
||
|
case WDIOC_GETSUPPORT:
|
||
|
if (copy_to_user((void *)arg, &info, sizeof(info)))
|
||
|
return -EFAULT;
|
||
|
break;
|
||
|
|
||
|
case WDIOC_GETSTATUS:
|
||
|
case WDIOC_GETBOOTSTATUS:
|
||
|
if (put_user(wdt_status, (int *)arg))
|
||
|
return -EFAULT;
|
||
|
wdt_status &= ~WDIOF_KEEPALIVEPING;
|
||
|
break;
|
||
|
|
||
|
case WDIOC_GETTEMP:
|
||
|
return -EOPNOTSUPP;
|
||
|
|
||
|
case WDIOC_SETOPTIONS:
|
||
|
return -EOPNOTSUPP;
|
||
|
|
||
|
case WDIOC_KEEPALIVE:
|
||
|
mv64x60_wdt_service();
|
||
|
wdt_status |= WDIOF_KEEPALIVEPING;
|
||
|
break;
|
||
|
|
||
|
case WDIOC_SETTIMEOUT:
|
||
|
return -EOPNOTSUPP;
|
||
|
|
||
|
case WDIOC_GETTIMEOUT:
|
||
|
timeout = mv64x60_wdt_timeout * HZ;
|
||
|
if (put_user(timeout, (int *)arg))
|
||
|
return -EFAULT;
|
||
|
break;
|
||
|
|
||
|
default:
|
||
|
return -ENOIOCTLCMD;
|
||
|
}
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static struct file_operations mv64x60_wdt_fops = {
|
||
|
.owner = THIS_MODULE,
|
||
|
.llseek = no_llseek,
|
||
|
.write = mv64x60_wdt_write,
|
||
|
.ioctl = mv64x60_wdt_ioctl,
|
||
|
.open = mv64x60_wdt_open,
|
||
|
.release = mv64x60_wdt_release,
|
||
|
};
|
||
|
|
||
|
static struct miscdevice mv64x60_wdt_miscdev = {
|
||
|
.minor = WATCHDOG_MINOR,
|
||
|
.name = "watchdog",
|
||
|
.fops = &mv64x60_wdt_fops,
|
||
|
};
|
||
|
|
||
|
static int __devinit mv64x60_wdt_probe(struct device *dev)
|
||
|
{
|
||
|
struct platform_device *pd = to_platform_device(dev);
|
||
|
struct mv64x60_wdt_pdata *pdata = pd->dev.platform_data;
|
||
|
int bus_clk = 133;
|
||
|
|
||
|
mv64x60_wdt_timeout = 10;
|
||
|
if (pdata) {
|
||
|
mv64x60_wdt_timeout = pdata->timeout;
|
||
|
bus_clk = pdata->bus_clk;
|
||
|
}
|
||
|
|
||
|
mv64x60_regs = mv64x60_get_bridge_vbase();
|
||
|
|
||
|
writel((mv64x60_wdt_timeout * (bus_clk * 1000000)) >> 8,
|
||
|
mv64x60_regs + MV64x60_WDT_WDC);
|
||
|
|
||
|
return misc_register(&mv64x60_wdt_miscdev);
|
||
|
}
|
||
|
|
||
|
static int __devexit mv64x60_wdt_remove(struct device *dev)
|
||
|
{
|
||
|
misc_deregister(&mv64x60_wdt_miscdev);
|
||
|
|
||
|
mv64x60_wdt_service();
|
||
|
mv64x60_wdt_handler_disable();
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static struct device_driver mv64x60_wdt_driver = {
|
||
|
.name = MV64x60_WDT_NAME,
|
||
|
.bus = &platform_bus_type,
|
||
|
.probe = mv64x60_wdt_probe,
|
||
|
.remove = __devexit_p(mv64x60_wdt_remove),
|
||
|
};
|
||
|
|
||
|
static struct platform_device *mv64x60_wdt_dev;
|
||
|
|
||
|
static int __init mv64x60_wdt_init(void)
|
||
|
{
|
||
|
int ret;
|
||
|
|
||
|
printk(KERN_INFO "MV64x60 watchdog driver\n");
|
||
|
|
||
|
mv64x60_wdt_dev = platform_device_register_simple(MV64x60_WDT_NAME,
|
||
|
-1, NULL, 0);
|
||
|
if (IS_ERR(mv64x60_wdt_dev)) {
|
||
|
ret = PTR_ERR(mv64x60_wdt_dev);
|
||
|
goto out;
|
||
|
}
|
||
|
|
||
|
ret = driver_register(&mv64x60_wdt_driver);
|
||
|
out:
|
||
|
return ret;
|
||
|
}
|
||
|
|
||
|
static void __exit mv64x60_wdt_exit(void)
|
||
|
{
|
||
|
driver_unregister(&mv64x60_wdt_driver);
|
||
|
platform_device_unregister(mv64x60_wdt_dev);
|
||
|
}
|
||
|
|
||
|
module_init(mv64x60_wdt_init);
|
||
|
module_exit(mv64x60_wdt_exit);
|
||
|
|
||
|
MODULE_AUTHOR("James Chapman <jchapman@katalix.com>");
|
||
|
MODULE_DESCRIPTION("MV64x60 watchdog driver");
|
||
|
MODULE_LICENSE("GPL");
|
||
|
MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
|