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Commit c5f8556c authored by David S. Miller's avatar David S. Miller
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cpwatchdog: Cleanup and convert to pure OF driver. 

Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent e25ecd08
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Showing with 436 additions and 599 deletions
drivers/sbus/char/cpwatchdog.c
View file @ c5f8556c
......@@ -11,6 +11,7 @@
* 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>
......@@ -25,36 +26,34 @@
#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 */
......@@ -69,6 +68,29 @@
#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:
*
......@@ -130,40 +152,12 @@
#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);
......@@ -171,234 +165,313 @@ MODULE_PARM_DESC(wd1_timeout, "Default watchdog1 timeout in 1/10secs");
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;
......@@ -408,9 +481,10 @@ static long wd_compat_ioctl(struct file *file, unsigned int cmd,
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;
......@@ -419,440 +493,203 @@ static long wd_compat_ioctl(struct file *file, unsigned int cmd,
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);
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