diff options
Diffstat (limited to 'target/linux/amazon/files/drivers/watchdog/amazon_wdt.c')
| -rw-r--r-- | target/linux/amazon/files/drivers/watchdog/amazon_wdt.c | 277 |
1 files changed, 277 insertions, 0 deletions
diff --git a/target/linux/amazon/files/drivers/watchdog/amazon_wdt.c b/target/linux/amazon/files/drivers/watchdog/amazon_wdt.c new file mode 100644 index 000000000..b18296b79 --- /dev/null +++ b/target/linux/amazon/files/drivers/watchdog/amazon_wdt.c @@ -0,0 +1,277 @@ +/* + * 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 2004 Wu Qi Ming <gokimi@msn.com> + * Copyright (C) 2007 John Crispin <blogic@openwrt.org> + */ + +#include <linux/version.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/sched.h> +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/string.h> +#include <linux/timer.h> +#include <linux/fs.h> +#include <linux/errno.h> +#include <linux/proc_fs.h> +#include <linux/stat.h> +#include <linux/tty.h> +#include <linux/selection.h> +#include <linux/kmod.h> +#include <linux/vmalloc.h> +#include <linux/kdev_t.h> +#include <linux/ioctl.h> +#include <asm/uaccess.h> +#include <asm/system.h> +#include <linux/platform_device.h> +#include <asm/amazon/amazon.h> +#include <asm/amazon/amazon_wdt.h> + +#define DRV_NAME "AMAZON WDT:" + +#undef AMAZON_WDT_DEBUG + +static int amazon_wdt_isopen = 0; + +#ifdef AMAZON_WDT_DEBUG +static struct proc_dir_entry* amazon_wdt_dir; +#endif + +int wdt_enable(int timeout) +{ + u32 hard_psw, ffpi; + int reload_value, divider = 1; + + ffpi = amazon_get_fpi_hz(); + + reload_value = 65536 - timeout * ffpi / 256; + + if (reload_value < 0) { + divider = 0; + reload_value = 65536 - timeout * ffpi / 16384; + } + + if (reload_value < 0){ + printk(KERN_INFO DRV_NAME "timeout too large %d\n", timeout); + return -EINVAL; + } + + printk(KERN_INFO DRV_NAME "timeout:%d reload_value: %8x\n", timeout, reload_value); + + hard_psw = (amazon_readl(AMAZON_WDT_CON0) & 0xffffff01) + + (amazon_readl(AMAZON_WDT_CON1) & 0xc) + 0xf0; + amazon_writel(hard_psw, AMAZON_WDT_CON0); + wmb(); + + amazon_writel((hard_psw & 0xff00) + (reload_value << 16) + 0xf2, AMAZON_WDT_CON0); + wmb(); + + amazon_writel(divider << 2, AMAZON_WDT_CON1); + wmb(); + + hard_psw = (amazon_readl(AMAZON_WDT_CON0) & 0xffffff01) + + (amazon_readl(AMAZON_WDT_CON1) & 0xc) + 0xf0; + amazon_writel(hard_psw, AMAZON_WDT_CON0); + wmb(); + + amazon_writel_masked(AMAZON_WDT_CON0, 0xff, 0xf3); + wmb(); + return 0; +} + +void wdt_disable(void) +{ + u32 hard_psw = 0; + + hard_psw = (amazon_readl(AMAZON_WDT_CON0) & 0xffffff01) + + (amazon_readl(AMAZON_WDT_CON1) & 0xc) + 0xf0; + amazon_writel(hard_psw, AMAZON_WDT_CON0); + wmb(); + + amazon_writel_masked(AMAZON_WDT_CON0, 0xff, 0xf2); + wmb(); + + amazon_writel_masked(AMAZON_WDT_CON1, 0x8, 0x8); + wmb(); + + hard_psw=(amazon_readl(AMAZON_WDT_CON0) & 0xffffff01) + + (amazon_readl(AMAZON_WDT_CON1) & 0xc) + 0xf0; + amazon_writel(hard_psw, AMAZON_WDT_CON0); + wmb(); + + amazon_writel_masked(AMAZON_WDT_CON0, 0xff, 0xf3); + wmb(); + + return; +} + +#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,36)) +static long wdt_ioctl(struct file *file, unsigned int cmd, unsigned long arg) +#else +static int wdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg) +#endif +{ + int result=0; + static int timeout=-1; + + switch(cmd){ + case AMAZON_WDT_IOC_START: + printk(KERN_INFO DRV_NAME "enable watch dog timer!\n"); + if (copy_from_user((void*)&timeout, (void*)arg, sizeof (int))) { + printk(KERN_INFO DRV_NAME "invalid argument\n"); + result=-EINVAL; + } else if ((result = wdt_enable(timeout)) < 0) { + timeout = -1; + } + break; + + case AMAZON_WDT_IOC_STOP: + printk(KERN_INFO DRV_NAME "disable watch dog timer\n"); + timeout = -1; + wdt_disable(); + break; + + case AMAZON_WDT_IOC_PING: + if (timeout < 0) { + result = -EIO; + } else { + result = wdt_enable(timeout); + } + break; + + default: + result=-EINVAL; + break; + } + return result; +} + +static ssize_t wdt_read(struct file *file, char *buf, size_t count, loff_t *offset) +{ + return 0; +} + +static ssize_t wdt_write(struct file *file, const char *buf, size_t count, loff_t *offset) +{ + return count; +} + +static int wdt_open(struct inode *inode, struct file *file) +{ + if (amazon_wdt_isopen == 1) + return -EBUSY; + + amazon_wdt_isopen = 1; + printk(KERN_INFO DRV_NAME "opened\n"); + return 0; +} + +static int wdt_release(struct inode *inode, struct file *file) +{ + amazon_wdt_isopen = 0; + printk(KERN_INFO DRV_NAME "closed\n"); + return 0; +} + +#ifdef AMAZON_WDT_DEBUG +int wdt_register_proc_read(char *buf, char **start, off_t offset, + int count, int *eof, void *data) +{ + int len=0; + len+=sprintf(buf+len,"NMISR: 0x%08x\n",AMAZON_WDT_REG32(AMAZON_WDT_NMISR)); + len+=sprintf(buf+len,"RST_REQ: 0x%08x\n",AMAZON_WDT_REG32(AMAZON_RST_REQ)); + len+=sprintf(buf+len,"RST_SR: 0x%08x\n",AMAZON_WDT_REG32(AMAZON_RST_SR)); + len+=sprintf(buf+len,"WDT_CON0: 0x%08x\n",AMAZON_WDT_REG32(AMAZON_WDT_CON0)); + len+=sprintf(buf+len,"WDT_CON1: 0x%08x\n",AMAZON_WDT_REG32(AMAZON_WDT_CON1)); + len+=sprintf(buf+len,"WDT_SR: 0x%08x\n",AMAZON_WDT_REG32(AMAZON_WDT_SR)); + *eof = 1; + return len; +} +#endif + +static struct file_operations wdt_fops = { + read: wdt_read, + write: wdt_write, +#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,36)) + unlocked_ioctl: wdt_ioctl, +#else + ioctl: wdt_ioctl, +#endif + open: wdt_open, + release: wdt_release, +}; + +static int amazon_wdt_probe(struct platform_device *dev) +{ + int result = result = register_chrdev(0, "watchdog", &wdt_fops); + + if (result < 0) { + printk(KERN_INFO DRV_NAME "cannot register device\n"); + return result; + } + +#ifdef AMAZON_WDT_DEBUG + amazon_wdt_dir=proc_mkdir("amazon_wdt",NULL); + create_proc_read_entry("wdt_register", 0, amazon_wdt_dir, + wdt_register_proc_read, NULL); +#endif + + amazon_wdt_isopen=0; + printk(KERN_INFO DRV_NAME "driver loaded but inactive\n"); + return 0; +} + +static int amazon_wdt_remove(struct platform_device *dev) +{ + unregister_chrdev(0, "watchdog"); +#ifdef AMAZON_WDT_DEBUG + remove_proc_entry("wdt_register", amazon_wdt_dir); + remove_proc_entry("amazon_wdt", NULL); +#endif + printk(KERN_INFO DRV_NAME "unregistered\n"); + return 0; +} + +static struct platform_driver amazon_wdt_driver = { + .probe = amazon_wdt_probe, + .remove = amazon_wdt_remove, + .driver = { + .name = "amazon_wdt", + .owner = THIS_MODULE, + }, +}; + +static int __init amazon_wdt_init(void) +{ + int ret = platform_driver_register(&amazon_wdt_driver); + if (ret) + printk(KERN_WARNING "amazon_wdt: error registering platfom driver!\n"); + return ret; +} + +static void __exit amazon_wdt_exit(void) +{ + platform_driver_unregister(&amazon_wdt_driver); +} + +module_init(amazon_wdt_init); +module_exit(amazon_wdt_exit); + +MODULE_LICENSE ("GPL"); +MODULE_AUTHOR("Infineon / John Crispin <blogic@openwrt.org>"); +MODULE_DESCRIPTION("AMAZON WDT driver"); + |