* reset 'stopped' watchdogs on affected platforms.
*
* Copyright (c) 2000 Eric Brower (ebrower@usa.net)
+ * Copyright (C) 2008 David S. Miller <davem@davemloft.net>
*/
#include <linux/kernel.h>
#include <linux/timer.h>
#include <linux/smp_lock.h>
#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+
#include <asm/irq.h>
-#include <asm/ebus.h>
-#include <asm/oplib.h>
#include <asm/uaccess.h>
#include <asm/watchdog.h>
+#define DRIVER_NAME "cpwd"
+#define PFX DRIVER_NAME ": "
+
#define WD_OBPNAME "watchdog"
-#define WD_BADMODEL "SUNW,501-5336"
+#define WD_BADMODEL "SUNW,501-5336"
#define WD_BTIMEOUT (jiffies + (HZ * 1000))
#define WD_BLIMIT 0xFFFF
-#define WD0_DEVNAME "watchdog0"
-#define WD1_DEVNAME "watchdog1"
-#define WD2_DEVNAME "watchdog2"
-
#define WD0_MINOR 212
#define WD1_MINOR 213
#define WD2_MINOR 214
+/* Internal driver definitions. */
+#define WD0_ID 0
+#define WD1_ID 1
+#define WD2_ID 2
+#define WD_NUMDEVS 3
-/* Internal driver definitions
- */
-#define WD0_ID 0 /* Watchdog0 */
-#define WD1_ID 1 /* Watchdog1 */
-#define WD2_ID 2 /* Watchdog2 */
-#define WD_NUMDEVS 3 /* Device contains 3 timers */
-
-#define WD_INTR_OFF 0 /* Interrupt disable value */
-#define WD_INTR_ON 1 /* Interrupt enable value */
+#define WD_INTR_OFF 0
+#define WD_INTR_ON 1
#define WD_STAT_INIT 0x01 /* Watchdog timer is initialized */
#define WD_STAT_BSTOP 0x02 /* Watchdog timer is brokenstopped */
#define WD_S_RUNNING 0x01 /* Watchdog device status running */
#define WD_S_EXPIRED 0x02 /* Watchdog device status expired */
+struct cpwd {
+ void __iomem *regs;
+ spinlock_t lock;
+
+ unsigned int irq;
+
+ unsigned long timeout;
+ bool enabled;
+ bool reboot;
+ bool broken;
+ bool initialized;
+
+ struct {
+ struct miscdevice misc;
+ void __iomem *regs;
+ u8 intr_mask;
+ u8 runstatus;
+ u16 timeout;
+ } devs[WD_NUMDEVS];
+};
+
+static struct cpwd *cpwd_device;
+
/* Sun uses Altera PLD EPF8820ATC144-4
* providing three hardware watchdogs:
*
#define PLD_IMASK (PLD_OFF + 0x00)
#define PLD_STATUS (PLD_OFF + 0x04)
-/* Individual timer structure
- */
-struct wd_timer {
- __u16 timeout;
- __u8 intr_mask;
- unsigned char runstatus;
- void __iomem *regs;
-};
-
-/* Device structure
- */
-struct wd_device {
- int irq;
- spinlock_t lock;
- unsigned char isbaddoggie; /* defective PLD */
- unsigned char opt_enable;
- unsigned char opt_reboot;
- unsigned short opt_timeout;
- unsigned char initialized;
- struct wd_timer watchdog[WD_NUMDEVS];
- void __iomem *regs;
-};
-
-static struct wd_device wd_dev = {
- 0, __SPIN_LOCK_UNLOCKED(wd_dev.lock), 0, 0, 0, 0,
-};
-
-static struct timer_list wd_timer;
+static struct timer_list cpwd_timer;
static int wd0_timeout = 0;
static int wd1_timeout = 0;
static int wd2_timeout = 0;
-#ifdef MODULE
module_param (wd0_timeout, int, 0);
MODULE_PARM_DESC(wd0_timeout, "Default watchdog0 timeout in 1/10secs");
module_param (wd1_timeout, int, 0);
module_param (wd2_timeout, int, 0);
MODULE_PARM_DESC(wd2_timeout, "Default watchdog2 timeout in 1/10secs");
-MODULE_AUTHOR
- ("Eric Brower <ebrower@usa.net>");
-MODULE_DESCRIPTION
- ("Hardware watchdog driver for Sun Microsystems CP1400/1500");
+MODULE_AUTHOR("Eric Brower <ebrower@usa.net>");
+MODULE_DESCRIPTION("Hardware watchdog driver for Sun Microsystems CP1400/1500");
MODULE_LICENSE("GPL");
-MODULE_SUPPORTED_DEVICE
- ("watchdog");
-#endif /* ifdef MODULE */
+MODULE_SUPPORTED_DEVICE("watchdog");
+
+static void cpwd_writew(u16 val, void __iomem *addr)
+{
+ writew(cpu_to_le16(val), addr);
+}
+static u16 cpwd_readw(void __iomem *addr)
+{
+ u16 val = readw(addr);
+
+ return le16_to_cpu(val);
+}
+
+static void cpwd_writeb(u8 val, void __iomem *addr)
+{
+ writeb(val, addr);
+}
+
+static u8 cpwd_readb(void __iomem *addr)
+{
+ return readb(addr);
+}
-/* Forward declarations of internal methods
+/* Enable or disable watchdog interrupts
+ * Because of the CP1400 defect this should only be
+ * called during initialzation or by wd_[start|stop]timer()
+ *
+ * index - sub-device index, or -1 for 'all'
+ * enable - non-zero to enable interrupts, zero to disable
*/
-#ifdef WD_DEBUG
-static void wd_dumpregs(void);
-#endif
-static irqreturn_t wd_interrupt(int irq, void *dev_id);
-static void wd_toggleintr(struct wd_timer* pTimer, int enable);
-static void wd_pingtimer(struct wd_timer* pTimer);
-static void wd_starttimer(struct wd_timer* pTimer);
-static void wd_resetbrokentimer(struct wd_timer* pTimer);
-static void wd_stoptimer(struct wd_timer* pTimer);
-static void wd_brokentimer(unsigned long data);
-static int wd_getstatus(struct wd_timer* pTimer);
-
-/* PLD expects words to be written in LSB format,
- * so we must flip all words prior to writing them to regs
+static void cpwd_toggleintr(struct cpwd *p, int index, int enable)
+{
+ unsigned char curregs = cpwd_readb(p->regs + PLD_IMASK);
+ unsigned char setregs =
+ (index == -1) ?
+ (WD0_INTR_MASK | WD1_INTR_MASK | WD2_INTR_MASK) :
+ (p->devs[index].intr_mask);
+
+ if (enable == WD_INTR_ON)
+ curregs &= ~setregs;
+ else
+ curregs |= setregs;
+
+ cpwd_writeb(curregs, p->regs + PLD_IMASK);
+}
+
+/* Restarts timer with maximum limit value and
+ * does not unset 'brokenstop' value.
*/
-static inline unsigned short flip_word(unsigned short word)
+static void cpwd_resetbrokentimer(struct cpwd *p, int index)
{
- return ((word & 0xff) << 8) | ((word >> 8) & 0xff);
+ cpwd_toggleintr(p, index, WD_INTR_ON);
+ cpwd_writew(WD_BLIMIT, p->devs[index].regs + WD_LIMIT);
}
-#define wd_writew(val, addr) (writew(flip_word(val), addr))
-#define wd_readw(addr) (flip_word(readw(addr)))
-#define wd_writeb(val, addr) (writeb(val, addr))
-#define wd_readb(addr) (readb(addr))
+/* Timer method called to reset stopped watchdogs--
+ * because of the PLD bug on CP1400, we cannot mask
+ * interrupts within the PLD so me must continually
+ * reset the timers ad infinitum.
+ */
+static void cpwd_brokentimer(unsigned long data)
+{
+ struct cpwd *p = (struct cpwd *) data;
+ int id, tripped = 0;
+
+ /* kill a running timer instance, in case we
+ * were called directly instead of by kernel timer
+ */
+ if (timer_pending(&cpwd_timer))
+ del_timer(&cpwd_timer);
+ for (id = 0; id < WD_NUMDEVS; id++) {
+ if (p->devs[id].runstatus & WD_STAT_BSTOP) {
+ ++tripped;
+ cpwd_resetbrokentimer(p, id);
+ }
+ }
-/* CP1400s seem to have broken PLD implementations--
- * the interrupt_mask register cannot be written, so
- * no timer interrupts can be masked within the PLD.
+ if (tripped) {
+ /* there is at least one timer brokenstopped-- reschedule */
+ cpwd_timer.expires = WD_BTIMEOUT;
+ add_timer(&cpwd_timer);
+ }
+}
+
+/* Reset countdown timer with 'limit' value and continue countdown.
+ * This will not start a stopped timer.
*/
-static inline int wd_isbroken(void)
+static void cpwd_pingtimer(struct cpwd *p, int index)
{
- /* we could test this by read/write/read/restore
- * on the interrupt mask register only if OBP
- * 'watchdog-enable?' == FALSE, but it seems
- * ubiquitous on CP1400s
- */
- char val[32];
- prom_getproperty(prom_root_node, "model", val, sizeof(val));
- return((!strcmp(val, WD_BADMODEL)) ? 1 : 0);
+ if (cpwd_readb(p->devs[index].regs + WD_STATUS) & WD_S_RUNNING)
+ cpwd_readw(p->devs[index].regs + WD_DCNTR);
}
-
-/* Retrieve watchdog-enable? option from OBP
- * Returns 0 if false, 1 if true
+
+/* Stop a running watchdog timer-- the timer actually keeps
+ * running, but the interrupt is masked so that no action is
+ * taken upon expiration.
*/
-static inline int wd_opt_enable(void)
+static void cpwd_stoptimer(struct cpwd *p, int index)
{
- int opt_node;
+ if (cpwd_readb(p->devs[index].regs + WD_STATUS) & WD_S_RUNNING) {
+ cpwd_toggleintr(p, index, WD_INTR_OFF);
- opt_node = prom_getchild(prom_root_node);
- opt_node = prom_searchsiblings(opt_node, "options");
- return((-1 == prom_getint(opt_node, "watchdog-enable?")) ? 0 : 1);
+ if (p->broken) {
+ p->devs[index].runstatus |= WD_STAT_BSTOP;
+ cpwd_brokentimer((unsigned long) p);
+ }
+ }
}
-/* Retrieve watchdog-reboot? option from OBP
- * Returns 0 if false, 1 if true
+/* Start a watchdog timer with the specified limit value
+ * If the watchdog is running, it will be restarted with
+ * the provided limit value.
+ *
+ * This function will enable interrupts on the specified
+ * watchdog.
*/
-static inline int wd_opt_reboot(void)
+static void cpwd_starttimer(struct cpwd *p, int index)
{
- int opt_node;
+ if (p->broken)
+ p->devs[index].runstatus &= ~WD_STAT_BSTOP;
+
+ p->devs[index].runstatus &= ~WD_STAT_SVCD;
- opt_node = prom_getchild(prom_root_node);
- opt_node = prom_searchsiblings(opt_node, "options");
- return((-1 == prom_getint(opt_node, "watchdog-reboot?")) ? 0 : 1);
+ cpwd_writew(p->devs[index].timeout, p->devs[index].regs + WD_LIMIT);
+ cpwd_toggleintr(p, index, WD_INTR_ON);
}
-/* Retrieve watchdog-timeout option from OBP
- * Returns OBP value, or 0 if not located
- */
-static inline int wd_opt_timeout(void)
+static int cpwd_getstatus(struct cpwd *p, int index)
{
- int opt_node;
- char value[32];
- char *p = value;
-
- opt_node = prom_getchild(prom_root_node);
- opt_node = prom_searchsiblings(opt_node, "options");
- opt_node = prom_getproperty(opt_node,
- "watchdog-timeout",
- value,
- sizeof(value));
- if(-1 != opt_node) {
- /* atoi implementation */
- for(opt_node = 0; /* nop */; p++) {
- if(*p >= '0' && *p <= '9') {
- opt_node = (10*opt_node)+(*p-'0');
- }
- else {
- break;
+ unsigned char stat = cpwd_readb(p->devs[index].regs + WD_STATUS);
+ unsigned char intr = cpwd_readb(p->devs[index].regs + PLD_IMASK);
+ unsigned char ret = WD_STOPPED;
+
+ /* determine STOPPED */
+ if (!stat)
+ return ret;
+
+ /* determine EXPIRED vs FREERUN vs RUNNING */
+ else if (WD_S_EXPIRED & stat) {
+ ret = WD_EXPIRED;
+ } else if(WD_S_RUNNING & stat) {
+ if (intr & p->devs[index].intr_mask) {
+ ret = WD_FREERUN;
+ } else {
+ /* Fudge WD_EXPIRED status for defective CP1400--
+ * IF timer is running
+ * AND brokenstop is set
+ * AND an interrupt has been serviced
+ * we are WD_EXPIRED.
+ *
+ * IF timer is running
+ * AND brokenstop is set
+ * AND no interrupt has been serviced
+ * we are WD_FREERUN.
+ */
+ if (p->broken &&
+ (p->devs[index].runstatus & WD_STAT_BSTOP)) {
+ if (p->devs[index].runstatus & WD_STAT_SVCD) {
+ ret = WD_EXPIRED;
+ } else {
+ /* we could as well pretend we are expired */
+ ret = WD_FREERUN;
+ }
+ } else {
+ ret = WD_RUNNING;
}
}
}
- return((-1 == opt_node) ? (0) : (opt_node));
+
+ /* determine SERVICED */
+ if (p->devs[index].runstatus & WD_STAT_SVCD)
+ ret |= WD_SERVICED;
+
+ return(ret);
+}
+
+static irqreturn_t cpwd_interrupt(int irq, void *dev_id)
+{
+ struct cpwd *p = dev_id;
+
+ /* Only WD0 will interrupt-- others are NMI and we won't
+ * see them here....
+ */
+ spin_lock_irq(&p->lock);
+
+ cpwd_stoptimer(p, WD0_ID);
+ p->devs[WD0_ID].runstatus |= WD_STAT_SVCD;
+
+ spin_unlock_irq(&p->lock);
+
+ return IRQ_HANDLED;
}
-static int wd_open(struct inode *inode, struct file *f)
+static int cpwd_open(struct inode *inode, struct file *f)
{
+ struct cpwd *p = cpwd_device;
+
lock_kernel();
- switch(iminor(inode))
- {
+ switch(iminor(inode)) {
case WD0_MINOR:
- f->private_data = &wd_dev.watchdog[WD0_ID];
- break;
case WD1_MINOR:
- f->private_data = &wd_dev.watchdog[WD1_ID];
- break;
case WD2_MINOR:
- f->private_data = &wd_dev.watchdog[WD2_ID];
break;
+
default:
unlock_kernel();
- return(-ENODEV);
+ return -ENODEV;
}
/* Register IRQ on first open of device */
- if(0 == wd_dev.initialized)
- {
- if (request_irq(wd_dev.irq,
- &wd_interrupt,
- IRQF_SHARED,
- WD_OBPNAME,
- (void *)wd_dev.regs)) {
- printk("%s: Cannot register IRQ %d\n",
- WD_OBPNAME, wd_dev.irq);
+ if (!p->initialized) {
+ if (request_irq(p->irq, &cpwd_interrupt,
+ IRQF_SHARED, DRIVER_NAME, p)) {
+ printk(KERN_ERR PFX "Cannot register IRQ %d\n",
+ p->irq);
unlock_kernel();
- return(-EBUSY);
+ return -EBUSY;
}
- wd_dev.initialized = 1;
+ p->initialized = true;
}
unlock_kernel();
- return(nonseekable_open(inode, f));
+
+ return nonseekable_open(inode, f);
}
-static int wd_release(struct inode *inode, struct file *file)
+static int cpwd_release(struct inode *inode, struct file *file)
{
return 0;
}
-static int wd_ioctl(struct inode *inode, struct file *file,
- unsigned int cmd, unsigned long arg)
+static int cpwd_ioctl(struct inode *inode, struct file *file,
+ unsigned int cmd, unsigned long arg)
{
- int setopt = 0;
- struct wd_timer* pTimer = (struct wd_timer*)file->private_data;
- void __user *argp = (void __user *)arg;
- struct watchdog_info info = {
- 0,
- 0,
- "Altera EPF8820ATC144-4"
+ static struct watchdog_info info = {
+ .options = WDIOF_SETTIMEOUT,
+ .firmware_version = 1,
+ .identity = DRIVER_NAME,
};
+ void __user *argp = (void __user *)arg;
+ int index = iminor(inode) - WD0_MINOR;
+ struct cpwd *p = cpwd_device;
+ int setopt = 0;
- if(NULL == pTimer) {
- return(-EINVAL);
- }
+ switch (cmd) {
+ /* Generic Linux IOCTLs */
+ case WDIOC_GETSUPPORT:
+ if (copy_to_user(argp, &info, sizeof(struct watchdog_info)))
+ return -EFAULT;
+ break;
- switch(cmd)
- {
- /* Generic Linux IOCTLs */
- case WDIOC_GETSUPPORT:
- if(copy_to_user(argp, &info, sizeof(struct watchdog_info))) {
- return(-EFAULT);
- }
- break;
- case WDIOC_GETSTATUS:
- case WDIOC_GETBOOTSTATUS:
- if (put_user(0, (int __user *)argp))
- return -EFAULT;
- break;
- case WDIOC_KEEPALIVE:
- wd_pingtimer(pTimer);
- break;
- case WDIOC_SETOPTIONS:
- if(copy_from_user(&setopt, argp, sizeof(unsigned int))) {
- return -EFAULT;
- }
- if(setopt & WDIOS_DISABLECARD) {
- if(wd_dev.opt_enable) {
- printk(
- "%s: cannot disable watchdog in ENABLED mode\n",
- WD_OBPNAME);
- return(-EINVAL);
- }
- wd_stoptimer(pTimer);
- }
- else if(setopt & WDIOS_ENABLECARD) {
- wd_starttimer(pTimer);
- }
- else {
- return(-EINVAL);
- }
- break;
- /* Solaris-compatible IOCTLs */
- case WIOCGSTAT:
- setopt = wd_getstatus(pTimer);
- if(copy_to_user(argp, &setopt, sizeof(unsigned int))) {
- return(-EFAULT);
- }
- break;
- case WIOCSTART:
- wd_starttimer(pTimer);
- break;
- case WIOCSTOP:
- if(wd_dev.opt_enable) {
- printk("%s: cannot disable watchdog in ENABLED mode\n",
- WD_OBPNAME);
- return(-EINVAL);
- }
- wd_stoptimer(pTimer);
- break;
- default:
+ case WDIOC_GETSTATUS:
+ case WDIOC_GETBOOTSTATUS:
+ if (put_user(0, (int __user *)argp))
+ return -EFAULT;
+ break;
+
+ case WDIOC_KEEPALIVE:
+ cpwd_pingtimer(p, index);
+ break;
+
+ case WDIOC_SETOPTIONS:
+ if (copy_from_user(&setopt, argp, sizeof(unsigned int)))
+ return -EFAULT;
+
+ if (setopt & WDIOS_DISABLECARD) {
+ if (p->enabled)
+ return -EINVAL;
+ cpwd_stoptimer(p, index);
+ } else if (setopt & WDIOS_ENABLECARD) {
+ cpwd_starttimer(p, index);
+ } else {
+ return -EINVAL;
+ }
+ break;
+
+ /* Solaris-compatible IOCTLs */
+ case WIOCGSTAT:
+ setopt = cpwd_getstatus(p, index);
+ if (copy_to_user(argp, &setopt, sizeof(unsigned int)))
+ return -EFAULT;
+ break;
+
+ case WIOCSTART:
+ cpwd_starttimer(p, index);
+ break;
+
+ case WIOCSTOP:
+ if (p->enabled)
return(-EINVAL);
+
+ cpwd_stoptimer(p, index);
+ break;
+
+ default:
+ return -EINVAL;
}
- return(0);
+
+ return 0;
}
-static long wd_compat_ioctl(struct file *file, unsigned int cmd,
- unsigned long arg)
+static long cpwd_compat_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
{
int rval = -ENOIOCTLCMD;
case WIOCSTOP:
case WIOCGSTAT:
lock_kernel();
- rval = wd_ioctl(file->f_path.dentry->d_inode, file, cmd, arg);
+ rval = cpwd_ioctl(file->f_path.dentry->d_inode, file, cmd, arg);
unlock_kernel();
break;
+
/* everything else is handled by the generic compat layer */
default:
break;
return rval;
}
-static ssize_t wd_write(struct file *file,
- const char __user *buf,
- size_t count,
- loff_t *ppos)
+static ssize_t cpwd_write(struct file *file, const char __user *buf,
+ size_t count, loff_t *ppos)
{
- struct wd_timer* pTimer = (struct wd_timer*)file->private_data;
-
- if(NULL == pTimer) {
- return(-EINVAL);
- }
+ struct inode *inode = file->f_path.dentry->d_inode;
+ struct cpwd *p = cpwd_device;
+ int index = iminor(inode);
if (count) {
- wd_pingtimer(pTimer);
+ cpwd_pingtimer(p, index);
return 1;
}
- return 0;
-}
-static ssize_t wd_read(struct file * file, char __user *buffer,
- size_t count, loff_t *ppos)
-{
-#ifdef WD_DEBUG
- wd_dumpregs();
- return(0);
-#else
- return(-EINVAL);
-#endif /* ifdef WD_DEBUG */
+ return 0;
}
-static irqreturn_t wd_interrupt(int irq, void *dev_id)
+static ssize_t cpwd_read(struct file * file, char __user *buffer,
+ size_t count, loff_t *ppos)
{
- /* Only WD0 will interrupt-- others are NMI and we won't
- * see them here....
- */
- spin_lock_irq(&wd_dev.lock);
- if((unsigned long)wd_dev.regs == (unsigned long)dev_id)
- {
- wd_stoptimer(&wd_dev.watchdog[WD0_ID]);
- wd_dev.watchdog[WD0_ID].runstatus |= WD_STAT_SVCD;
- }
- spin_unlock_irq(&wd_dev.lock);
- return IRQ_HANDLED;
+ return -EINVAL;
}
-static const struct file_operations wd_fops = {
+static const struct file_operations cpwd_fops = {
.owner = THIS_MODULE,
- .ioctl = wd_ioctl,
- .compat_ioctl = wd_compat_ioctl,
- .open = wd_open,
- .write = wd_write,
- .read = wd_read,
- .release = wd_release,
+ .ioctl = cpwd_ioctl,
+ .compat_ioctl = cpwd_compat_ioctl,
+ .open = cpwd_open,
+ .write = cpwd_write,
+ .read = cpwd_read,
+ .release = cpwd_release,
};
-static struct miscdevice wd0_miscdev = { WD0_MINOR, WD0_DEVNAME, &wd_fops };
-static struct miscdevice wd1_miscdev = { WD1_MINOR, WD1_DEVNAME, &wd_fops };
-static struct miscdevice wd2_miscdev = { WD2_MINOR, WD2_DEVNAME, &wd_fops };
-
-#ifdef WD_DEBUG
-static void wd_dumpregs(void)
+static int __devinit cpwd_probe(struct of_device *op,
+ const struct of_device_id *match)
{
- /* Reading from downcounters initiates watchdog countdown--
- * Example is included below for illustration purposes.
- */
- int i;
- printk("%s: dumping register values\n", WD_OBPNAME);
- for(i = WD0_ID; i < WD_NUMDEVS; ++i) {
- /* printk("\t%s%i: dcntr at 0x%lx: 0x%x\n",
- * WD_OBPNAME,
- * i,
- * (unsigned long)(&wd_dev.watchdog[i].regs->dcntr),
- * readw(&wd_dev.watchdog[i].regs->dcntr));
- */
- printk("\t%s%i: limit at 0x%lx: 0x%x\n",
- WD_OBPNAME,
- i,
- (unsigned long)(&wd_dev.watchdog[i].regs->limit),
- readw(&wd_dev.watchdog[i].regs->limit));
- printk("\t%s%i: status at 0x%lx: 0x%x\n",
- WD_OBPNAME,
- i,
- (unsigned long)(&wd_dev.watchdog[i].regs->status),
- readb(&wd_dev.watchdog[i].regs->status));
- printk("\t%s%i: driver status: 0x%x\n",
- WD_OBPNAME,
- i,
- wd_getstatus(&wd_dev.watchdog[i]));
- }
- printk("\tintr_mask at %p: 0x%x\n",
- wd_dev.regs + PLD_IMASK,
- readb(wd_dev.regs + PLD_IMASK));
- printk("\tpld_status at %p: 0x%x\n",
- wd_dev.regs + PLD_STATUS,
- readb(wd_dev.regs + PLD_STATUS));
-}
-#endif
-
-/* Enable or disable watchdog interrupts
- * Because of the CP1400 defect this should only be
- * called during initialzation or by wd_[start|stop]timer()
- *
- * pTimer - pointer to timer device, or NULL to indicate all timers
- * enable - non-zero to enable interrupts, zero to disable
- */
-static void wd_toggleintr(struct wd_timer* pTimer, int enable)
-{
- unsigned char curregs = wd_readb(wd_dev.regs + PLD_IMASK);
- unsigned char setregs =
- (NULL == pTimer) ?
- (WD0_INTR_MASK | WD1_INTR_MASK | WD2_INTR_MASK) :
- (pTimer->intr_mask);
-
- (WD_INTR_ON == enable) ?
- (curregs &= ~setregs):
- (curregs |= setregs);
+ struct device_node *options;
+ const char *str_prop;
+ const void *prop_val;
+ int i, err = -EINVAL;
+ struct cpwd *p;
- wd_writeb(curregs, wd_dev.regs + PLD_IMASK);
- return;
-}
+ if (cpwd_device)
+ return -EINVAL;
-/* Reset countdown timer with 'limit' value and continue countdown.
- * This will not start a stopped timer.
- *
- * pTimer - pointer to timer device
- */
-static void wd_pingtimer(struct wd_timer* pTimer)
-{
- if (wd_readb(pTimer->regs + WD_STATUS) & WD_S_RUNNING) {
- wd_readw(pTimer->regs + WD_DCNTR);
+ p = kzalloc(sizeof(*p), GFP_KERNEL);
+ err = -ENOMEM;
+ if (!p) {
+ printk(KERN_ERR PFX "Unable to allocate struct cpwd.\n");
+ goto out;
}
-}
-/* Stop a running watchdog timer-- the timer actually keeps
- * running, but the interrupt is masked so that no action is
- * taken upon expiration.
- *
- * pTimer - pointer to timer device
- */
-static void wd_stoptimer(struct wd_timer* pTimer)
-{
- if(wd_readb(pTimer->regs + WD_STATUS) & WD_S_RUNNING) {
- wd_toggleintr(pTimer, WD_INTR_OFF);
+ p->irq = op->irqs[0];
- if(wd_dev.isbaddoggie) {
- pTimer->runstatus |= WD_STAT_BSTOP;
- wd_brokentimer((unsigned long)&wd_dev);
- }
- }
-}
+ spin_lock_init(&p->lock);
-/* Start a watchdog timer with the specified limit value
- * If the watchdog is running, it will be restarted with
- * the provided limit value.
- *
- * This function will enable interrupts on the specified
- * watchdog.
- *
- * pTimer - pointer to timer device
- * limit - limit (countdown) value in 1/10th seconds
- */
-static void wd_starttimer(struct wd_timer* pTimer)
-{
- if(wd_dev.isbaddoggie) {
- pTimer->runstatus &= ~WD_STAT_BSTOP;
+ p->regs = of_ioremap(&op->resource[0], 0,
+ 4 * WD_TIMER_REGSZ, DRIVER_NAME);
+ if (!p->regs) {
+ printk(KERN_ERR PFX "Unable to map registers.\n");
+ goto out_free;
}
- pTimer->runstatus &= ~WD_STAT_SVCD;
- wd_writew(pTimer->timeout, pTimer->regs + WD_LIMIT);
- wd_toggleintr(pTimer, WD_INTR_ON);
-}
+ options = of_find_node_by_path("/options");
+ err = -ENODEV;
+ if (!options) {
+ printk(KERN_ERR PFX "Unable to find /options node.\n");
+ goto out_iounmap;
+ }
-/* Restarts timer with maximum limit value and
- * does not unset 'brokenstop' value.
- */
-static void wd_resetbrokentimer(struct wd_timer* pTimer)
-{
- wd_toggleintr(pTimer, WD_INTR_ON);
- wd_writew(WD_BLIMIT, pTimer->regs + WD_LIMIT);
-}
+ prop_val = of_get_property(options, "watchdog-enable?", NULL);
+ p->enabled = (prop_val ? true : false);
-/* Timer device initialization helper.
- * Returns 0 on success, other on failure
- */
-static int wd_inittimer(int whichdog)
-{
- struct miscdevice *whichmisc;
- void __iomem *whichregs;
- char whichident[8];
- int whichmask;
- __u16 whichlimit;
+ prop_val = of_get_property(options, "watchdog-reboot?", NULL);
+ p->reboot = (prop_val ? true : false);
- switch(whichdog)
- {
- case WD0_ID:
- whichmisc = &wd0_miscdev;
- strcpy(whichident, "RIC");
- whichregs = wd_dev.regs + WD0_OFF;
- whichmask = WD0_INTR_MASK;
- whichlimit= (0 == wd0_timeout) ?
- (wd_dev.opt_timeout):
- (wd0_timeout);
- break;
- case WD1_ID:
- whichmisc = &wd1_miscdev;
- strcpy(whichident, "XIR");
- whichregs = wd_dev.regs + WD1_OFF;
- whichmask = WD1_INTR_MASK;
- whichlimit= (0 == wd1_timeout) ?
- (wd_dev.opt_timeout):
- (wd1_timeout);
- break;
- case WD2_ID:
- whichmisc = &wd2_miscdev;
- strcpy(whichident, "POR");
- whichregs = wd_dev.regs + WD2_OFF;
- whichmask = WD2_INTR_MASK;
- whichlimit= (0 == wd2_timeout) ?
- (wd_dev.opt_timeout):
- (wd2_timeout);
- break;
- default:
- printk("%s: %s: invalid watchdog id: %i\n",
- WD_OBPNAME, __func__, whichdog);
- return(1);
- }
- if(0 != misc_register(whichmisc))
- {
- return(1);
- }
- wd_dev.watchdog[whichdog].regs = whichregs;
- wd_dev.watchdog[whichdog].timeout = whichlimit;
- wd_dev.watchdog[whichdog].intr_mask = whichmask;
- wd_dev.watchdog[whichdog].runstatus &= ~WD_STAT_BSTOP;
- wd_dev.watchdog[whichdog].runstatus |= WD_STAT_INIT;
-
- printk("%s%i: %s hardware watchdog [%01i.%i sec] %s\n",
- WD_OBPNAME,
- whichdog,
- whichident,
- wd_dev.watchdog[whichdog].timeout / 10,
- wd_dev.watchdog[whichdog].timeout % 10,
- (0 != wd_dev.opt_enable) ? "in ENABLED mode" : "");
- return(0);
-}
+ str_prop = of_get_property(options, "watchdog-timeout", NULL);
+ if (str_prop)
+ p->timeout = simple_strtoul(str_prop, NULL, 10);
-/* Timer method called to reset stopped watchdogs--
- * because of the PLD bug on CP1400, we cannot mask
- * interrupts within the PLD so me must continually
- * reset the timers ad infinitum.
- */
-static void wd_brokentimer(unsigned long data)
-{
- struct wd_device* pDev = (struct wd_device*)data;
- int id, tripped = 0;
-
- /* kill a running timer instance, in case we
- * were called directly instead of by kernel timer
+ /* CP1400s seem to have broken PLD implementations-- the
+ * interrupt_mask register cannot be written, so no timer
+ * interrupts can be masked within the PLD.
*/
- if(timer_pending(&wd_timer)) {
- del_timer(&wd_timer);
- }
-
- for(id = WD0_ID; id < WD_NUMDEVS; ++id) {
- if(pDev->watchdog[id].runstatus & WD_STAT_BSTOP) {
- ++tripped;
- wd_resetbrokentimer(&pDev->watchdog[id]);
+ str_prop = of_get_property(op->node, "model", NULL);
+ p->broken = (str_prop && !strcmp(str_prop, WD_BADMODEL));
+
+ if (!p->enabled)
+ cpwd_toggleintr(p, -1, WD_INTR_OFF);
+
+ for (i = 0; i < WD_NUMDEVS; i++) {
+ static const char *cpwd_names[] = { "RIC", "XIR", "POR" };
+ static int *parms[] = { &wd0_timeout,
+ &wd1_timeout,
+ &wd2_timeout };
+ struct miscdevice *mp = &p->devs[i].misc;
+
+ mp->minor = WD0_MINOR + i;
+ mp->name = cpwd_names[i];
+ mp->fops = &cpwd_fops;
+
+ p->devs[i].regs = p->regs + (i * WD_TIMER_REGSZ);
+ p->devs[i].intr_mask = (WD0_INTR_MASK << i);
+ p->devs[i].runstatus &= ~WD_STAT_BSTOP;
+ p->devs[i].runstatus |= WD_STAT_INIT;
+ p->devs[i].timeout = p->timeout;
+ if (*parms[i])
+ p->devs[i].timeout = *parms[i];
+
+ err = misc_register(&p->devs[i].misc);
+ if (err) {
+ printk(KERN_ERR "Could not register misc device for "
+ "dev %d\n", i);
+ goto out_unregister;
}
}
- if(tripped) {
- /* there is at least one timer brokenstopped-- reschedule */
- init_timer(&wd_timer);
- wd_timer.expires = WD_BTIMEOUT;
- add_timer(&wd_timer);
+ if (p->broken) {
+ init_timer(&cpwd_timer);
+ cpwd_timer.function = cpwd_brokentimer;
+ cpwd_timer.data = (unsigned long) p;
+ cpwd_timer.expires = WD_BTIMEOUT;
+
+ printk(KERN_INFO PFX "PLD defect workaround enabled for "
+ "model " WD_BADMODEL ".\n");
}
-}
-static int wd_getstatus(struct wd_timer* pTimer)
-{
- unsigned char stat = wd_readb(pTimer->regs + WD_STATUS);
- unsigned char intr = wd_readb(wd_dev.regs + PLD_IMASK);
- unsigned char ret = WD_STOPPED;
+ dev_set_drvdata(&op->dev, p);
+ cpwd_device = p;
+ err = 0;
- /* determine STOPPED */
- if(0 == stat ) {
- return(ret);
- }
- /* determine EXPIRED vs FREERUN vs RUNNING */
- else if(WD_S_EXPIRED & stat) {
- ret = WD_EXPIRED;
- }
- else if(WD_S_RUNNING & stat) {
- if(intr & pTimer->intr_mask) {
- ret = WD_FREERUN;
- }
- else {
- /* Fudge WD_EXPIRED status for defective CP1400--
- * IF timer is running
- * AND brokenstop is set
- * AND an interrupt has been serviced
- * we are WD_EXPIRED.
- *
- * IF timer is running
- * AND brokenstop is set
- * AND no interrupt has been serviced
- * we are WD_FREERUN.
- */
- if(wd_dev.isbaddoggie && (pTimer->runstatus & WD_STAT_BSTOP)) {
- if(pTimer->runstatus & WD_STAT_SVCD) {
- ret = WD_EXPIRED;
- }
- else {
- /* we could as well pretend we are expired */
- ret = WD_FREERUN;
- }
- }
- else {
- ret = WD_RUNNING;
- }
- }
- }
+out:
+ return err;
- /* determine SERVICED */
- if(pTimer->runstatus & WD_STAT_SVCD) {
- ret |= WD_SERVICED;
- }
+out_unregister:
+ for (i--; i >= 0; i--)
+ misc_deregister(&p->devs[i].misc);
- return(ret);
+out_iounmap:
+ of_iounmap(&op->resource[0], p->regs, 4 * WD_TIMER_REGSZ);
+
+out_free:
+ kfree(p);
+ goto out;
}
-static int __init wd_init(void)
+static int __devexit cpwd_remove(struct of_device *op)
{
- int id;
- 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, WD_OBPNAME))
- goto ebus_done;
+ struct cpwd *p = dev_get_drvdata(&op->dev);
+ int i;
+
+ for (i = 0; i < 4; i++) {
+ misc_deregister(&p->devs[i].misc);
+
+ if (!p->enabled) {
+ cpwd_stoptimer(p, i);
+ if (p->devs[i].runstatus & WD_STAT_BSTOP)
+ cpwd_resetbrokentimer(p, i);
}
}
-ebus_done:
- if(!edev) {
- printk("%s: unable to locate device\n", WD_OBPNAME);
- return -ENODEV;
- }
+ if (p->broken)
+ del_timer_sync(&cpwd_timer);
- wd_dev.regs =
- ioremap(edev->resource[0].start, 4 * WD_TIMER_REGSZ); /* ? */
+ if (p->initialized)
+ free_irq(p->irq, p);
- if(NULL == wd_dev.regs) {
- printk("%s: unable to map registers\n", WD_OBPNAME);
- return(-ENODEV);
- }
+ of_iounmap(&op->resource[0], p->regs, 4 * WD_TIMER_REGSZ);
+ kfree(p);
- /* initialize device structure from OBP parameters */
- wd_dev.irq = edev->irqs[0];
- wd_dev.opt_enable = wd_opt_enable();
- wd_dev.opt_reboot = wd_opt_reboot();
- wd_dev.opt_timeout = wd_opt_timeout();
- wd_dev.isbaddoggie = wd_isbroken();
+ cpwd_device = NULL;
- /* disable all interrupts unless watchdog-enabled? == true */
- if(! wd_dev.opt_enable) {
- wd_toggleintr(NULL, WD_INTR_OFF);
- }
+ return 0;
+}
- /* register miscellaneous devices */
- for(id = WD0_ID; id < WD_NUMDEVS; ++id) {
- if(0 != wd_inittimer(id)) {
- printk("%s%i: unable to initialize\n", WD_OBPNAME, id);
- }
- }
+static struct of_device_id cpwd_match[] = {
+ {
+ .name = "watchdog",
+ },
+ {},
+};
+MODULE_DEVICE_TABLE(of, cpwd_match);
- /* warn about possible defective PLD */
- if(wd_dev.isbaddoggie) {
- init_timer(&wd_timer);
- wd_timer.function = wd_brokentimer;
- wd_timer.data = (unsigned long)&wd_dev;
- wd_timer.expires = WD_BTIMEOUT;
+static struct of_platform_driver cpwd_driver = {
+ .name = DRIVER_NAME,
+ .match_table = cpwd_match,
+ .probe = cpwd_probe,
+ .remove = __devexit_p(cpwd_remove),
+};
- printk("%s: PLD defect workaround enabled for model %s\n",
- WD_OBPNAME, WD_BADMODEL);
- }
- return(0);
+static int __init cpwd_init(void)
+{
+ return of_register_driver(&cpwd_driver, &of_bus_type);
}
-static void __exit wd_cleanup(void)
+static void __exit cpwd_exit(void)
{
- int id;
-
- /* if 'watchdog-enable?' == TRUE, timers are not stopped
- * when module is unloaded. All brokenstopped timers will
- * also now eventually trip.
- */
- for(id = WD0_ID; id < WD_NUMDEVS; ++id) {
- if(WD_S_RUNNING == wd_readb(wd_dev.watchdog[id].regs + WD_STATUS)) {
- if(wd_dev.opt_enable) {
- printk(KERN_WARNING "%s%i: timer not stopped at release\n",
- WD_OBPNAME, id);
- }
- else {
- wd_stoptimer(&wd_dev.watchdog[id]);
- if(wd_dev.watchdog[id].runstatus & WD_STAT_BSTOP) {
- wd_resetbrokentimer(&wd_dev.watchdog[id]);
- printk(KERN_WARNING
- "%s%i: defect workaround disabled at release, "\
- "timer expires in ~%01i sec\n",
- WD_OBPNAME, id,
- wd_readw(wd_dev.watchdog[id].regs + WD_LIMIT) / 10);
- }
- }
- }
- }
-
- if(wd_dev.isbaddoggie && timer_pending(&wd_timer)) {
- del_timer(&wd_timer);
- }
- if(0 != (wd_dev.watchdog[WD0_ID].runstatus & WD_STAT_INIT)) {
- misc_deregister(&wd0_miscdev);
- }
- if(0 != (wd_dev.watchdog[WD1_ID].runstatus & WD_STAT_INIT)) {
- misc_deregister(&wd1_miscdev);
- }
- if(0 != (wd_dev.watchdog[WD2_ID].runstatus & WD_STAT_INIT)) {
- misc_deregister(&wd2_miscdev);
- }
- if(0 != wd_dev.initialized) {
- free_irq(wd_dev.irq, (void *)wd_dev.regs);
- }
- iounmap(wd_dev.regs);
+ of_unregister_driver(&cpwd_driver);
}
-module_init(wd_init);
-module_exit(wd_cleanup);
+module_init(cpwd_init);
+module_exit(cpwd_exit);
projects / linux-2.6-omap-h63xx.git / commitdiff