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path: root/drivers/sbus/char/cpwatchdog.c
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Diffstat (limited to 'drivers/sbus/char/cpwatchdog.c')
-rw-r--r--drivers/sbus/char/cpwatchdog.c695
1 files changed, 0 insertions, 695 deletions
diff --git a/drivers/sbus/char/cpwatchdog.c b/drivers/sbus/char/cpwatchdog.c
deleted file mode 100644
index c88df62e705..00000000000
--- a/drivers/sbus/char/cpwatchdog.c
+++ /dev/null
@@ -1,695 +0,0 @@
-/* cpwatchdog.c - driver implementation for hardware watchdog
- * timers found on Sun Microsystems CP1400 and CP1500 boards.
- *
- * This device supports both the generic Linux watchdog
- * interface and Solaris-compatible ioctls as best it is
- * able.
- *
- * NOTE: CP1400 systems appear to have a defective intr_mask
- * register on the PLD, preventing the disabling of
- * timer interrupts. We use a timer to periodically
- * 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/module.h>
-#include <linux/fs.h>
-#include <linux/errno.h>
-#include <linux/major.h>
-#include <linux/init.h>
-#include <linux/miscdevice.h>
-#include <linux/interrupt.h>
-#include <linux/ioport.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/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_BTIMEOUT (jiffies + (HZ * 1000))
-#define WD_BLIMIT 0xFFFF
-
-#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
-
-#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_STAT_SVCD 0x04 /* Watchdog interrupt occurred */
-
-/* Register value definitions
- */
-#define WD0_INTR_MASK 0x01 /* Watchdog device interrupt masks */
-#define WD1_INTR_MASK 0x02
-#define WD2_INTR_MASK 0x04
-
-#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:
- *
- * 1) RIC - sends an interrupt when triggered
- * 2) XIR - asserts XIR_B_RESET when triggered, resets CPU
- * 3) POR - asserts POR_B_RESET when triggered, resets CPU, backplane, board
- *
- *** Timer register block definition (struct wd_timer_regblk)
- *
- * dcntr and limit registers (halfword access):
- * -------------------
- * | 15 | ...| 1 | 0 |
- * -------------------
- * |- counter val -|
- * -------------------
- * dcntr - Current 16-bit downcounter value.
- * When downcounter reaches '0' watchdog expires.
- * Reading this register resets downcounter with 'limit' value.
- * limit - 16-bit countdown value in 1/10th second increments.
- * Writing this register begins countdown with input value.
- * Reading from this register does not affect counter.
- * NOTES: After watchdog reset, dcntr and limit contain '1'
- *
- * status register (byte access):
- * ---------------------------
- * | 7 | ... | 2 | 1 | 0 |
- * --------------+------------
- * |- UNUSED -| EXP | RUN |
- * ---------------------------
- * status- Bit 0 - Watchdog is running
- * Bit 1 - Watchdog has expired
- *
- *** PLD register block definition (struct wd_pld_regblk)
- *
- * intr_mask register (byte access):
- * ---------------------------------
- * | 7 | ... | 3 | 2 | 1 | 0 |
- * +-------------+------------------
- * |- UNUSED -| WD3 | WD2 | WD1 |
- * ---------------------------------
- * WD3 - 1 == Interrupt disabled for watchdog 3
- * WD2 - 1 == Interrupt disabled for watchdog 2
- * WD1 - 1 == Interrupt disabled for watchdog 1
- *
- * pld_status register (byte access):
- * UNKNOWN, MAGICAL MYSTERY REGISTER
- *
- */
-#define WD_TIMER_REGSZ 16
-#define WD0_OFF 0
-#define WD1_OFF (WD_TIMER_REGSZ * 1)
-#define WD2_OFF (WD_TIMER_REGSZ * 2)
-#define PLD_OFF (WD_TIMER_REGSZ * 3)
-
-#define WD_DCNTR 0x00
-#define WD_LIMIT 0x04
-#define WD_STATUS 0x08
-
-#define PLD_IMASK (PLD_OFF + 0x00)
-#define PLD_STATUS (PLD_OFF + 0x04)
-
-static struct timer_list cpwd_timer;
-
-static int wd0_timeout = 0;
-static int wd1_timeout = 0;
-static int wd2_timeout = 0;
-
-module_param (wd0_timeout, int, 0);
-MODULE_PARM_DESC(wd0_timeout, "Default watchdog0 timeout in 1/10secs");
-module_param (wd1_timeout, int, 0);
-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_LICENSE("GPL");
-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);
-}
-
-/* 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
- */
-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 void cpwd_resetbrokentimer(struct cpwd *p, int index)
-{
- cpwd_toggleintr(p, index, WD_INTR_ON);
- cpwd_writew(WD_BLIMIT, p->devs[index].regs + WD_LIMIT);
-}
-
-/* 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);
- }
- }
-
- 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 void cpwd_pingtimer(struct cpwd *p, int index)
-{
- if (cpwd_readb(p->devs[index].regs + WD_STATUS) & WD_S_RUNNING)
- cpwd_readw(p->devs[index].regs + WD_DCNTR);
-}
-
-/* Stop a running watchdog timer-- the timer actually keeps
- * running, but the interrupt is masked so that no action is
- * taken upon expiration.
- */
-static void cpwd_stoptimer(struct cpwd *p, int index)
-{
- if (cpwd_readb(p->devs[index].regs + WD_STATUS) & WD_S_RUNNING) {
- cpwd_toggleintr(p, index, WD_INTR_OFF);
-
- if (p->broken) {
- p->devs[index].runstatus |= WD_STAT_BSTOP;
- cpwd_brokentimer((unsigned long) p);
- }
- }
-}
-
-/* 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 void cpwd_starttimer(struct cpwd *p, int index)
-{
- if (p->broken)
- p->devs[index].runstatus &= ~WD_STAT_BSTOP;
-
- p->devs[index].runstatus &= ~WD_STAT_SVCD;
-
- cpwd_writew(p->devs[index].timeout, p->devs[index].regs + WD_LIMIT);
- cpwd_toggleintr(p, index, WD_INTR_ON);
-}
-
-static int cpwd_getstatus(struct cpwd *p, int index)
-{
- 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;
- }
- }
- }
-
- /* 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 cpwd_open(struct inode *inode, struct file *f)
-{
- struct cpwd *p = cpwd_device;
-
- lock_kernel();
- switch(iminor(inode)) {
- case WD0_MINOR:
- case WD1_MINOR:
- case WD2_MINOR:
- break;
-
- default:
- unlock_kernel();
- return -ENODEV;
- }
-
- /* Register IRQ on first open of device */
- 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;
- }
- p->initialized = true;
- }
-
- unlock_kernel();
-
- return nonseekable_open(inode, f);
-}
-
-static int cpwd_release(struct inode *inode, struct file *file)
-{
- return 0;
-}
-
-static int cpwd_ioctl(struct inode *inode, struct file *file,
- unsigned int cmd, unsigned long arg)
-{
- 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;
-
- 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:
- 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;
-}
-
-static long cpwd_compat_ioctl(struct file *file, unsigned int cmd,
- unsigned long arg)
-{
- int rval = -ENOIOCTLCMD;
-
- switch (cmd) {
- /* solaris ioctls are specific to this driver */
- case WIOCSTART:
- case WIOCSTOP:
- case WIOCGSTAT:
- lock_kernel();
- 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 cpwd_write(struct file *file, const char __user *buf,
- size_t count, loff_t *ppos)
-{
- struct inode *inode = file->f_path.dentry->d_inode;
- struct cpwd *p = cpwd_device;
- int index = iminor(inode);
-
- if (count) {
- cpwd_pingtimer(p, index);
- return 1;
- }
-
- return 0;
-}
-
-static ssize_t cpwd_read(struct file * file, char __user *buffer,
- size_t count, loff_t *ppos)
-{
- return -EINVAL;
-}
-
-static const struct file_operations cpwd_fops = {
- .owner = THIS_MODULE,
- .ioctl = cpwd_ioctl,
- .compat_ioctl = cpwd_compat_ioctl,
- .open = cpwd_open,
- .write = cpwd_write,
- .read = cpwd_read,
- .release = cpwd_release,
-};
-
-static int __devinit cpwd_probe(struct of_device *op,
- const struct of_device_id *match)
-{
- struct device_node *options;
- const char *str_prop;
- const void *prop_val;
- int i, err = -EINVAL;
- struct cpwd *p;
-
- if (cpwd_device)
- return -EINVAL;
-
- p = kzalloc(sizeof(*p), GFP_KERNEL);
- err = -ENOMEM;
- if (!p) {
- printk(KERN_ERR PFX "Unable to allocate struct cpwd.\n");
- goto out;
- }
-
- p->irq = op->irqs[0];
-
- spin_lock_init(&p->lock);
-
- 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;
- }
-
- options = of_find_node_by_path("/options");
- err = -ENODEV;
- if (!options) {
- printk(KERN_ERR PFX "Unable to find /options node.\n");
- goto out_iounmap;
- }
-
- prop_val = of_get_property(options, "watchdog-enable?", NULL);
- p->enabled = (prop_val ? true : false);
-
- prop_val = of_get_property(options, "watchdog-reboot?", NULL);
- p->reboot = (prop_val ? true : false);
-
- str_prop = of_get_property(options, "watchdog-timeout", NULL);
- if (str_prop)
- p->timeout = simple_strtoul(str_prop, NULL, 10);
-
- /* CP1400s seem to have broken PLD implementations-- the
- * interrupt_mask register cannot be written, so no timer
- * interrupts can be masked within the PLD.
- */
- 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 (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");
- }
-
- dev_set_drvdata(&op->dev, p);
- cpwd_device = p;
- err = 0;
-
-out:
- return err;
-
-out_unregister:
- for (i--; i >= 0; i--)
- misc_deregister(&p->devs[i].misc);
-
-out_iounmap:
- of_iounmap(&op->resource[0], p->regs, 4 * WD_TIMER_REGSZ);
-
-out_free:
- kfree(p);
- goto out;
-}
-
-static int __devexit cpwd_remove(struct of_device *op)
-{
- 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);
- }
- }
-
- if (p->broken)
- del_timer_sync(&cpwd_timer);
-
- if (p->initialized)
- free_irq(p->irq, p);
-
- of_iounmap(&op->resource[0], p->regs, 4 * WD_TIMER_REGSZ);
- kfree(p);
-
- cpwd_device = NULL;
-
- return 0;
-}
-
-static struct of_device_id cpwd_match[] = {
- {
- .name = "watchdog",
- },
- {},
-};
-MODULE_DEVICE_TABLE(of, cpwd_match);
-
-static struct of_platform_driver cpwd_driver = {
- .name = DRIVER_NAME,
- .match_table = cpwd_match,
- .probe = cpwd_probe,
- .remove = __devexit_p(cpwd_remove),
-};
-
-static int __init cpwd_init(void)
-{
- return of_register_driver(&cpwd_driver, &of_bus_type);
-}
-
-static void __exit cpwd_exit(void)
-{
- of_unregister_driver(&cpwd_driver);
-}
-
-module_init(cpwd_init);
-module_exit(cpwd_exit);