diff options
Diffstat (limited to 'drivers/sbus/char/cpwatchdog.c')
| -rw-r--r-- | drivers/sbus/char/cpwatchdog.c | 695 |
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); |