diff options
Diffstat (limited to 'target/linux/brcm63xx/files/arch/mips/bcm963xx/wdt.c')
| -rw-r--r-- | target/linux/brcm63xx/files/arch/mips/bcm963xx/wdt.c | 246 |
1 files changed, 246 insertions, 0 deletions
diff --git a/target/linux/brcm63xx/files/arch/mips/bcm963xx/wdt.c b/target/linux/brcm63xx/files/arch/mips/bcm963xx/wdt.c new file mode 100644 index 0000000..0ea36a6 --- /dev/null +++ b/target/linux/brcm63xx/files/arch/mips/bcm963xx/wdt.c @@ -0,0 +1,246 @@ +/* + * Watchdog driver for the BCM963xx devices + * + * Copyright (C) 2007 OpenWrt.org + * Florian Fainelli <florian@openwrt.org> + * + * 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. + */ + +#include <linux/module.h> +#include <linux/types.h> +#include <linux/errno.h> +#include <linux/miscdevice.h> +#include <linux/fs.h> +#include <linux/init.h> +#include <linux/notifier.h> +#include <linux/watchdog.h> +#include <linux/timer.h> +#include <linux/jiffies.h> +#include <linux/completion.h> +#include <linux/ioport.h> + +typedef struct bcm963xx_timer { + unsigned short unused0; + unsigned char timer_mask; +#define TIMER0EN 0x01 +#define TIMER1EN 0x02 +#define TIMER2EN 0x04 + unsigned char timer_ints; +#define TIMER0 0x01 +#define TIMER1 0x02 +#define TIMER2 0x04 +#define WATCHDOG 0x08 + unsigned long timer_ctl0; + unsigned long timer_ctl1; + unsigned long timer_ctl2; +#define TIMERENABLE 0x80000000 +#define RSTCNTCLR 0x40000000 + unsigned long timer_cnt0; + unsigned long timer_cnt1; + unsigned long timer_cnt2; + unsigned long wdt_def_count; + + /* Write 0xff00 0x00ff to Start timer + * Write 0xee00 0x00ee to Stop and re-load default count + * Read from this register returns current watch dog count + */ + unsigned long wdt_ctl; + + /* Number of 40-MHz ticks for WD Reset pulse to last */ + unsigned long wdt_rst_count; +} bcm963xx_timer; + +static struct bcm963xx_wdt_device { + struct completion stop; + volatile int running; + struct timer_list timer; + volatile int queue; + int default_ticks; + unsigned long inuse; +} bcm963xx_wdt_device; + +static int ticks = 1000; + +#define WDT_BASE 0xfffe0200 +#define WDT ((volatile bcm963xx_timer * const) WDT_BASE) + +#define BCM963XX_INTERVAL (HZ/10+1) + +static void bcm963xx_wdt_trigger(unsigned long unused) +{ + if (bcm963xx_wdt_device.running) + ticks--; + + /* Load the default ticking value into the reset counter register */ + WDT->wdt_rst_count = bcm963xx_wdt_device.default_ticks; + + if (bcm963xx_wdt_device.queue && ticks) { + bcm963xx_wdt_device.timer.expires = jiffies + BCM963XX_INTERVAL; + add_timer(&bcm963xx_wdt_device.timer); + } + else { + complete(&bcm963xx_wdt_device.stop); + } +} + +static void bcm963xx_wdt_reset(void) +{ + ticks = bcm963xx_wdt_device.default_ticks; + /* Also reload default count */ + WDT->wdt_def_count = ticks; + WDT->wdt_ctl = 0xee00; + WDT->wdt_ctl = 0x00ee; +} + +static void bcm963xx_wdt_start(void) +{ + if (!bcm963xx_wdt_device.queue) { + bcm963xx_wdt_device.queue; + /* Enable the watchdog by writing 0xff00 ,then 0x00ff to the control register */ + WDT->wdt_ctl = 0xff00; + WDT->wdt_ctl = 0x00ff; + bcm963xx_wdt_device.timer.expires = jiffies + BCM963XX_INTERVAL; + add_timer(&bcm963xx_wdt_device.timer); + } + bcm963xx_wdt_device.running++; +} + +static int bcm963xx_wdt_stop(void) +{ + if (bcm963xx_wdt_device.running) + bcm963xx_wdt_device.running = 0; + + ticks = bcm963xx_wdt_device.default_ticks; + + /* Stop the watchdog by writing 0xee00 then 0x00ee to the control register */ + WDT->wdt_ctl = 0xee00; + WDT->wdt_ctl = 0x00ee; + + return -EIO; +} + +static int bcm963xx_wdt_open(struct inode *inode, struct file *file) +{ + if (test_and_set_bit(0, &bcm963xx_wdt_device.inuse)) + return -EBUSY; + return nonseekable_open(inode, file); +} + +static int bcm963xx_wdt_release(struct inode *inode, struct file *file) +{ + clear_bit(0, &bcm963xx_wdt_device.inuse); + return 0; +} + +static int bcm963xx_wdt_ioctl(struct inode *inode, struct file *file, + unsigned int cmd, unsigned long arg) +{ + void __user *argp = (void __user *)arg; + unsigned int value; + + static struct watchdog_info ident = { + .options = WDIOF_CARDRESET, + .identity = "BCM963xx WDT", + }; + + switch (cmd) { + case WDIOC_KEEPALIVE: + bcm963xx_wdt_reset(); + break; + case WDIOC_GETSTATUS: + /* Reading from the control register will return the current value */ + value = WDT->wdt_ctl; + if ( copy_to_user(argp, &value, sizeof(int)) ) + return -EFAULT; + break; + case WDIOC_GETSUPPORT: + if ( copy_to_user(argp, &ident, sizeof(ident)) ) + return -EFAULT; + break; + case WDIOC_SETOPTIONS: + if ( copy_from_user(&value, argp, sizeof(int)) ) + return -EFAULT; + switch(value) { + case WDIOS_ENABLECARD: + bcm963xx_wdt_start(); + break; + case WDIOS_DISABLECARD: + bcm963xx_wdt_stop(); + break; + default: + return -EINVAL; + } + break; + default: + return -ENOTTY; + } + return 0; +} + +static int bcm963xx_wdt_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos) +{ + if (!count) + return -EIO; + bcm963xx_wdt_reset(); + return count; +} + +static const struct file_operations bcm963xx_wdt_fops = { + .owner = THIS_MODULE, + .llseek = no_llseek, + .write = bcm963xx_wdt_write, + .ioctl = bcm963xx_wdt_ioctl, + .open = bcm963xx_wdt_open, + .release = bcm963xx_wdt_release, +}; + +static struct miscdevice bcm963xx_wdt_miscdev = { + .minor = WATCHDOG_MINOR, + .name = "watchdog", + .fops = &bcm963xx_wdt_fops, +}; + +static void __exit bcm963xx_wdt_exit(void) +{ + if (bcm963xx_wdt_device.queue ){ + bcm963xx_wdt_device.queue = 0; + wait_for_completion(&bcm963xx_wdt_device.stop); + } + misc_deregister(&bcm963xx_wdt_miscdev); +} + +static int __init bcm963xx_wdt_init(void) +{ + int ret = 0; + + printk("Broadcom BCM963xx Watchdog timer\n"); + + ret = misc_register(&bcm963xx_wdt_miscdev); + if (ret) { + printk(KERN_CRIT "Cannot register miscdev on minor=%d (err=%d)\n", WATCHDOG_MINOR, ret); + return ret; + } + init_completion(&bcm963xx_wdt_device.stop); + bcm963xx_wdt_device.queue = 0; + + clear_bit(0, &bcm963xx_wdt_device.inuse); + + init_timer(&bcm963xx_wdt_device.timer); + bcm963xx_wdt_device.timer.function = bcm963xx_wdt_trigger; + bcm963xx_wdt_device.timer.data = 0; + + bcm963xx_wdt_device.default_ticks = ticks; + return ret; +} + + +module_init(bcm963xx_wdt_init); +module_exit(bcm963xx_wdt_exit); + +MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>"); +MODULE_DESCRIPTION("Broadcom BCM963xx Watchdog driver"); +MODULE_LICENSE("GPL"); |