openwrt/target/linux/ifxmips/files/drivers/watchdog/ifxmips_wdt.c

326 lines
7.9 KiB
C

/*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
*
* Copyright (C) 2006 infineon
* Copyright (C) 2007 John Crispin <blogic@openwrt.org>
*
*/
#include <asm/uaccess.h>
#include <linux/errno.h>
#include <linux/proc_fs.h>
#include <linux/ioctl.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/watchdog.h>
#include <linux/miscdevice.h>
#include <asm-mips/ifxmips/ifxmips_wdt.h>
#include <asm-mips/ifxmips/ifxmips.h>
#define DRVNAME "ifxmips_wdt"
// TODO remove magic numbers and weirdo macros
extern unsigned int ifxmips_get_fpi_hz (void);
static int ifxmips_wdt_inuse = 0;
static int ifxmips_wdt_major = 0;
int
ifxmips_wdt_enable (unsigned int timeout)
{
unsigned int wdt_cr = 0;
unsigned int wdt_reload = 0;
unsigned int wdt_clkdiv, wdt_pwl, ffpi;
int retval = 0;
/* clock divider & prewarning limit */
wdt_clkdiv = 1 << (7 * IFXMIPS_BIU_WDT_CR_CLKDIV_GET(readl(IFXMIPS_BIU_WDT_CR)));
wdt_pwl = 0x8000 >> IFXMIPS_BIU_WDT_CR_PWL_GET(readl(IFXMIPS_BIU_WDT_CR));
//TODO
printk("WARNING FUNCTION CALL MISSING!!!");
//ffpi = cgu_get_io_region_clock();
printk("cpu clock = %d\n", ffpi);
/* caculate reload value */
wdt_reload = (timeout * (ffpi / wdt_clkdiv)) + wdt_pwl;
printk(KERN_WARNING DRVNAME ": wdt_pwl=0x%x, wdt_clkdiv=%d, ffpi=%d, wdt_reload = 0x%x\n",
wdt_pwl, wdt_clkdiv, ffpi, wdt_reload);
if (wdt_reload > 0xFFFF)
{
printk(KERN_WARNING DRVNAME ": timeout too large %d\n", timeout);
retval = -EINVAL;
goto out;
}
/* Write first part of password access */
writel(IFXMIPS_BIU_WDT_CR_PW_SET(IFXMIPS_WDT_PW1), IFXMIPS_BIU_WDT_CR);
wdt_cr = readl(IFXMIPS_BIU_WDT_CR);
wdt_cr &= (!IFXMIPS_BIU_WDT_CR_PW_SET(0xff) &
!IFXMIPS_BIU_WDT_CR_PWL_SET(0x3) &
!IFXMIPS_BIU_WDT_CR_CLKDIV_SET(0x3) &
!IFXMIPS_BIU_WDT_CR_RELOAD_SET(0xffff));
wdt_cr |= (IFXMIPS_BIU_WDT_CR_PW_SET(IFXMIPS_WDT_PW2) |
IFXMIPS_BIU_WDT_CR_PWL_SET(IFXMIPS_BIU_WDT_CR_PWL_GET(readl(IFXMIPS_BIU_WDT_CR))) |
IFXMIPS_BIU_WDT_CR_CLKDIV_SET(IFXMIPS_BIU_WDT_CR_CLKDIV_GET(readl(IFXMIPS_BIU_WDT_CR))) |
IFXMIPS_BIU_WDT_CR_RELOAD_SET(wdt_reload) |
IFXMIPS_BIU_WDT_CR_GEN);
writel(wdt_cr, IFXMIPS_BIU_WDT_CR);
printk("watchdog enabled\n");
out:
return retval;
}
void
ifxmips_wdt_disable (void)
{
writel(IFXMIPS_BIU_WDT_CR_PW_SET(IFXMIPS_WDT_PW1), IFXMIPS_BIU_WDT_CR);
writel(IFXMIPS_BIU_WDT_CR_PW_SET(IFXMIPS_WDT_PW2), IFXMIPS_BIU_WDT_CR);
printk("watchdog disabled\n");
}
/* passed LPEN or DSEN */
void
ifxmips_wdt_enable_feature (int en, int type)
{
unsigned int wdt_cr = 0;
writel(IFXMIPS_BIU_WDT_CR_PW_SET(IFXMIPS_WDT_PW1), IFXMIPS_BIU_WDT_CR);
wdt_cr = readl(IFXMIPS_BIU_WDT_CR);
if (en)
{
wdt_cr &= (~IFXMIPS_BIU_WDT_CR_PW_SET(0xff));
wdt_cr |= (IFXMIPS_BIU_WDT_CR_PW_SET(IFXMIPS_WDT_PW2) | type);
} else {
wdt_cr &= (~IFXMIPS_BIU_WDT_CR_PW_SET(0xff) & ~type);
wdt_cr |= IFXMIPS_BIU_WDT_CR_PW_SET(IFXMIPS_WDT_PW2);
}
writel(wdt_cr, IFXMIPS_BIU_WDT_CR);
}
void
ifxmips_wdt_prewarning_limit (int pwl)
{
unsigned int wdt_cr = 0;
wdt_cr = readl(IFXMIPS_BIU_WDT_CR);
writel(IFXMIPS_BIU_WDT_CR_PW_SET(IFXMIPS_WDT_PW1), IFXMIPS_BIU_WDT_CR);
wdt_cr &= 0xf300ffff;
wdt_cr |= (IFXMIPS_BIU_WDT_CR_PW_SET(IFXMIPS_WDT_PW2) | IFXMIPS_BIU_WDT_CR_PWL_SET(pwl));
/* Set reload value in second password access */
writel(wdt_cr, IFXMIPS_BIU_WDT_CR);
}
void
ifxmips_wdt_set_clkdiv (int clkdiv)
{
unsigned int wdt_cr = 0;
wdt_cr = readl(IFXMIPS_BIU_WDT_CR);
writel(IFXMIPS_BIU_WDT_CR_PW_SET(IFXMIPS_WDT_PW1), IFXMIPS_BIU_WDT_CR);
wdt_cr &= 0xfc00ffff;
wdt_cr |= (IFXMIPS_BIU_WDT_CR_PW_SET(IFXMIPS_WDT_PW2) | IFXMIPS_BIU_WDT_CR_CLKDIV_SET(clkdiv));
/* Set reload value in second password access */
writel(wdt_cr, IFXMIPS_BIU_WDT_CR);
}
static int
ifxmips_wdt_ioctl (struct inode *inode, struct file *file, unsigned int cmd,
unsigned long arg)
{
int result = 0;
static int timeout = -1;
unsigned int user_arg;
if ((cmd != IFXMIPS_WDT_IOC_STOP) && (cmd != IFXMIPS_WDT_IOC_PING) && (cmd != IFXMIPS_WDT_IOC_GET_STATUS))
{
if (copy_from_user((void *) &user_arg, (void *) arg, sizeof (int))){
result = -EINVAL;
goto out;
}
}
switch (cmd)
{
case IFXMIPS_WDT_IOC_START:
if ((result = ifxmips_wdt_enable(user_arg)) < 0)
timeout = -1;
else
timeout = user_arg;
break;
case IFXMIPS_WDT_IOC_STOP:
printk(KERN_INFO DRVNAME ": disable watch dog timer\n");
ifxmips_wdt_disable();
break;
case IFXMIPS_WDT_IOC_PING:
if (timeout < 0)
result = -EIO;
else
result = ifxmips_wdt_enable(timeout);
break;
case IFXMIPS_WDT_IOC_GET_STATUS:
user_arg = readl(IFXMIPS_BIU_WDT_SR);
copy_to_user((int*)arg, (int*)&user_arg, sizeof(int));
break;
case IFXMIPS_WDT_IOC_SET_PWL:
ifxmips_wdt_prewarning_limit(user_arg);
break;
case IFXMIPS_WDT_IOC_SET_DSEN:
ifxmips_wdt_enable_feature(user_arg, IFXMIPS_BIU_WDT_CR_DSEN);
break;
case IFXMIPS_WDT_IOC_SET_LPEN:
ifxmips_wdt_enable_feature(user_arg, IFXMIPS_BIU_WDT_CR_LPEN);
break;
case IFXMIPS_WDT_IOC_SET_CLKDIV:
ifxmips_wdt_set_clkdiv(user_arg);
break;
default:
printk(KERN_WARNING DRVNAME ": unknown watchdog iotcl\n");
}
out:
return result;
}
static int
ifxmips_wdt_open (struct inode *inode, struct file *file)
{
if (ifxmips_wdt_inuse)
return -EBUSY;
ifxmips_wdt_inuse = 1;
return 0;
}
static int
ifxmips_wdt_release (struct inode *inode, struct file *file)
{
ifxmips_wdt_inuse = 0;
return 0;
}
int
ifxmips_wdt_register_proc_read (char *buf, char **start, off_t offset, int count,
int *eof, void *data)
{
int len = 0;
len += sprintf (buf + len, "IFXMIPS_BIU_WDT_PROC_READ\n");
len += sprintf (buf + len, "IFXMIPS_BIU_WDT_CR(0x%08x) : 0x%08x\n",
(unsigned int)IFXMIPS_BIU_WDT_CR, readl(IFXMIPS_BIU_WDT_CR));
len += sprintf (buf + len, "IFXMIPS_BIU_WDT_SR(0x%08x) : 0x%08x\n",
(unsigned int)IFXMIPS_BIU_WDT_SR, readl(IFXMIPS_BIU_WDT_SR));
*eof = 1;
return len;
}
static const struct file_operations ifxmips_wdt_fops = {
.owner = THIS_MODULE,
.llseek = no_llseek,
.ioctl = ifxmips_wdt_ioctl,
.open = ifxmips_wdt_open,
.release = ifxmips_wdt_release,
// .write = at91_wdt_write,
};
static struct miscdevice ifxmips_wdt_miscdev = {
.minor = WATCHDOG_MINOR,
.name = "ifxmips_wdt",
.fops = &ifxmips_wdt_fops,
};
static int
ifxmips_wdt_probe (struct platform_device *pdev)
{
int ret = misc_register(&ifxmips_wdt_miscdev);
if (ret)
return ret;
create_proc_read_entry(DRVNAME, 0, NULL, ifxmips_wdt_register_proc_read, NULL);
printk(KERN_INFO DRVNAME ": ifxmips watchdog loaded\n");
return 0;
}
static int
ifxmips_wdt_remove (struct platform_device *pdev)
{
misc_deregister(&ifxmips_wdt_miscdev);
remove_proc_entry(DRVNAME, NULL);
return 0;
}
static struct
platform_driver ifxmips_wdt_driver = {
.probe = ifxmips_wdt_probe,
.remove = ifxmips_wdt_remove,
.driver = {
.name = DRVNAME,
.owner = THIS_MODULE,
},
};
int __init
ifxmips_wdt_init_module (void)
{
int ret = platform_driver_register(&ifxmips_wdt_driver);
if (ret)
printk(KERN_INFO DRVNAME ": Error registering platfom driver!");
return ret;
}
void
ifxmips_wdt_cleanup_module (void)
{
platform_driver_unregister(&ifxmips_wdt_driver);
}
module_init(ifxmips_wdt_init_module);
module_exit(ifxmips_wdt_cleanup_module);
MODULE_AUTHOR("John Crispin <blogic@openwrt.org>");
MODULE_DESCRIPTION("Watchdog driver for infineon ifxmips family");
MODULE_LICENSE("GPL");
MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);