296 lines
6.5 KiB
C
296 lines
6.5 KiB
C
/* $Id: riowatchdog.c,v 1.3.2.2 2002/01/23 18:48:02 davem Exp $
|
|
* riowatchdog.c - driver for hw watchdog inside Super I/O of RIO
|
|
*
|
|
* Copyright (C) 2001 David S. Miller (davem@redhat.com)
|
|
*/
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/types.h>
|
|
#include <linux/fs.h>
|
|
#include <linux/errno.h>
|
|
#include <linux/init.h>
|
|
#include <linux/miscdevice.h>
|
|
#include <linux/smp_lock.h>
|
|
|
|
#include <asm/io.h>
|
|
#include <asm/ebus.h>
|
|
#include <asm/bbc.h>
|
|
#include <asm/oplib.h>
|
|
#include <asm/uaccess.h>
|
|
|
|
#include <asm/watchdog.h>
|
|
|
|
/* RIO uses the NatSemi Super I/O power management logical device
|
|
* as its' watchdog.
|
|
*
|
|
* When the watchdog triggers, it asserts a line to the BBC (Boot Bus
|
|
* Controller) of the machine. The BBC can only be configured to
|
|
* trigger a power-on reset when the signal is asserted. The BBC
|
|
* can be configured to ignore the signal entirely as well.
|
|
*
|
|
* The only Super I/O device register we care about is at index
|
|
* 0x05 (WDTO_INDEX) which is the watchdog time-out in minutes (1-255).
|
|
* If set to zero, this disables the watchdog. When set, the system
|
|
* must periodically (before watchdog expires) clear (set to zero) and
|
|
* re-set the watchdog else it will trigger.
|
|
*
|
|
* There are two other indexed watchdog registers inside this Super I/O
|
|
* logical device, but they are unused. The first, at index 0x06 is
|
|
* the watchdog control and can be used to make the watchdog timer re-set
|
|
* when the PS/2 mouse or serial lines show activity. The second, at
|
|
* index 0x07 is merely a sampling of the line from the watchdog to the
|
|
* BBC.
|
|
*
|
|
* The watchdog device generates no interrupts.
|
|
*/
|
|
|
|
MODULE_AUTHOR("David S. Miller <davem@redhat.com>");
|
|
MODULE_DESCRIPTION("Hardware watchdog driver for Sun RIO");
|
|
MODULE_SUPPORTED_DEVICE("watchdog");
|
|
MODULE_LICENSE("GPL");
|
|
|
|
#define RIOWD_NAME "pmc"
|
|
#define RIOWD_MINOR 215
|
|
|
|
static DEFINE_SPINLOCK(riowd_lock);
|
|
|
|
static void __iomem *bbc_regs;
|
|
static void __iomem *riowd_regs;
|
|
#define WDTO_INDEX 0x05
|
|
|
|
static int riowd_timeout = 1; /* in minutes */
|
|
module_param(riowd_timeout, int, 0);
|
|
MODULE_PARM_DESC(riowd_timeout, "Watchdog timeout in minutes");
|
|
|
|
#if 0 /* Currently unused. */
|
|
static u8 riowd_readreg(int index)
|
|
{
|
|
unsigned long flags;
|
|
u8 ret;
|
|
|
|
spin_lock_irqsave(&riowd_lock, flags);
|
|
writeb(index, riowd_regs + 0);
|
|
ret = readb(riowd_regs + 1);
|
|
spin_unlock_irqrestore(&riowd_lock, flags);
|
|
|
|
return ret;
|
|
}
|
|
#endif
|
|
|
|
static void riowd_writereg(u8 val, int index)
|
|
{
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&riowd_lock, flags);
|
|
writeb(index, riowd_regs + 0);
|
|
writeb(val, riowd_regs + 1);
|
|
spin_unlock_irqrestore(&riowd_lock, flags);
|
|
}
|
|
|
|
static void riowd_pingtimer(void)
|
|
{
|
|
riowd_writereg(riowd_timeout, WDTO_INDEX);
|
|
}
|
|
|
|
static void riowd_stoptimer(void)
|
|
{
|
|
u8 val;
|
|
|
|
riowd_writereg(0, WDTO_INDEX);
|
|
|
|
val = readb(bbc_regs + BBC_WDACTION);
|
|
val &= ~BBC_WDACTION_RST;
|
|
writeb(val, bbc_regs + BBC_WDACTION);
|
|
}
|
|
|
|
static void riowd_starttimer(void)
|
|
{
|
|
u8 val;
|
|
|
|
riowd_writereg(riowd_timeout, WDTO_INDEX);
|
|
|
|
val = readb(bbc_regs + BBC_WDACTION);
|
|
val |= BBC_WDACTION_RST;
|
|
writeb(val, bbc_regs + BBC_WDACTION);
|
|
}
|
|
|
|
static int riowd_open(struct inode *inode, struct file *filp)
|
|
{
|
|
cycle_kernel_lock();
|
|
nonseekable_open(inode, filp);
|
|
return 0;
|
|
}
|
|
|
|
static int riowd_release(struct inode *inode, struct file *filp)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static int riowd_ioctl(struct inode *inode, struct file *filp,
|
|
unsigned int cmd, unsigned long arg)
|
|
{
|
|
static struct watchdog_info info = {
|
|
WDIOF_SETTIMEOUT, 0, "Natl. Semiconductor PC97317"
|
|
};
|
|
void __user *argp = (void __user *)arg;
|
|
unsigned int options;
|
|
int new_margin;
|
|
|
|
switch (cmd) {
|
|
case WDIOC_GETSUPPORT:
|
|
if (copy_to_user(argp, &info, sizeof(info)))
|
|
return -EFAULT;
|
|
break;
|
|
|
|
case WDIOC_GETSTATUS:
|
|
case WDIOC_GETBOOTSTATUS:
|
|
if (put_user(0, (int __user *)argp))
|
|
return -EFAULT;
|
|
break;
|
|
|
|
case WDIOC_KEEPALIVE:
|
|
riowd_pingtimer();
|
|
break;
|
|
|
|
case WDIOC_SETOPTIONS:
|
|
if (copy_from_user(&options, argp, sizeof(options)))
|
|
return -EFAULT;
|
|
|
|
if (options & WDIOS_DISABLECARD)
|
|
riowd_stoptimer();
|
|
else if (options & WDIOS_ENABLECARD)
|
|
riowd_starttimer();
|
|
else
|
|
return -EINVAL;
|
|
|
|
break;
|
|
|
|
case WDIOC_SETTIMEOUT:
|
|
if (get_user(new_margin, (int __user *)argp))
|
|
return -EFAULT;
|
|
if ((new_margin < 60) || (new_margin > (255 * 60)))
|
|
return -EINVAL;
|
|
riowd_timeout = (new_margin + 59) / 60;
|
|
riowd_pingtimer();
|
|
/* Fall */
|
|
|
|
case WDIOC_GETTIMEOUT:
|
|
return put_user(riowd_timeout * 60, (int __user *)argp);
|
|
|
|
default:
|
|
return -EINVAL;
|
|
};
|
|
|
|
return 0;
|
|
}
|
|
|
|
static ssize_t riowd_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
|
|
{
|
|
if (count) {
|
|
riowd_pingtimer();
|
|
return 1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct file_operations riowd_fops = {
|
|
.owner = THIS_MODULE,
|
|
.ioctl = riowd_ioctl,
|
|
.open = riowd_open,
|
|
.write = riowd_write,
|
|
.release = riowd_release,
|
|
};
|
|
|
|
static struct miscdevice riowd_miscdev = { RIOWD_MINOR, RIOWD_NAME, &riowd_fops };
|
|
|
|
static int __init riowd_bbc_init(void)
|
|
{
|
|
struct linux_ebus *ebus = NULL;
|
|
struct linux_ebus_device *edev = NULL;
|
|
u8 val;
|
|
|
|
for_each_ebus(ebus) {
|
|
for_each_ebusdev(edev, ebus) {
|
|
if (!strcmp(edev->ofdev.node->name, "bbc"))
|
|
goto found_bbc;
|
|
}
|
|
}
|
|
|
|
found_bbc:
|
|
if (!edev)
|
|
return -ENODEV;
|
|
bbc_regs = ioremap(edev->resource[0].start, BBC_REGS_SIZE);
|
|
if (!bbc_regs)
|
|
return -ENODEV;
|
|
|
|
/* Turn it off. */
|
|
val = readb(bbc_regs + BBC_WDACTION);
|
|
val &= ~BBC_WDACTION_RST;
|
|
writeb(val, bbc_regs + BBC_WDACTION);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int __init riowd_init(void)
|
|
{
|
|
struct linux_ebus *ebus = NULL;
|
|
struct linux_ebus_device *edev = NULL;
|
|
|
|
for_each_ebus(ebus) {
|
|
for_each_ebusdev(edev, ebus) {
|
|
if (!strcmp(edev->ofdev.node->name, RIOWD_NAME))
|
|
goto ebus_done;
|
|
}
|
|
}
|
|
|
|
ebus_done:
|
|
if (!edev)
|
|
goto fail;
|
|
|
|
riowd_regs = ioremap(edev->resource[0].start, 2);
|
|
if (riowd_regs == NULL) {
|
|
printk(KERN_ERR "pmc: Cannot map registers.\n");
|
|
return -ENODEV;
|
|
}
|
|
|
|
if (riowd_bbc_init()) {
|
|
printk(KERN_ERR "pmc: Failure initializing BBC config.\n");
|
|
goto fail;
|
|
}
|
|
|
|
if (misc_register(&riowd_miscdev)) {
|
|
printk(KERN_ERR "pmc: Cannot register watchdog misc device.\n");
|
|
goto fail;
|
|
}
|
|
|
|
printk(KERN_INFO "pmc: Hardware watchdog [%i minutes], "
|
|
"regs at %p\n", riowd_timeout, riowd_regs);
|
|
|
|
return 0;
|
|
|
|
fail:
|
|
if (riowd_regs) {
|
|
iounmap(riowd_regs);
|
|
riowd_regs = NULL;
|
|
}
|
|
if (bbc_regs) {
|
|
iounmap(bbc_regs);
|
|
bbc_regs = NULL;
|
|
}
|
|
return -ENODEV;
|
|
}
|
|
|
|
static void __exit riowd_cleanup(void)
|
|
{
|
|
misc_deregister(&riowd_miscdev);
|
|
iounmap(riowd_regs);
|
|
riowd_regs = NULL;
|
|
iounmap(bbc_regs);
|
|
bbc_regs = NULL;
|
|
}
|
|
|
|
module_init(riowd_init);
|
|
module_exit(riowd_cleanup);
|