[PATCH] WDT Driver for Book-E [2/2] Device driver part.

Kumar Gala kumar.gala at freescale.com
Sat Mar 5 03:02:40 EST 2005


Matt,

Do you think this really needs a config option?  Should it not be  
sufficient that if you enable watchdog you get this functionality on  
4xx/e500?

- kumar

On Mar 4, 2005, at 3:38 AM, Takeharu KATO wrote:

> Matt and Kurmar:
>
> I post the device driver part with this mail.
>
> This is the last part of this driver.
>
> Please apply.
>
> Regards,
>
> Signed-off-by: Takeharu KATO <kato.takeharu at jp.fujitsu.com>
>
> --- linux-2.6.11/drivers/char/watchdog/Kconfig  2005-03-04  
> 17:14:57.687966296 +0900
>  +++ linux-2.6.11-booke-wdt/drivers/char/watchdog/Kconfig         
> 2005-03-04 13:21:32.000000000 +0900
>  @@ -346,6 +346,13 @@ config 8xx_WDT
>          tristate "MPC8xx Watchdog Timer"
>          depends on WATCHDOG && 8xx
>
> +config BOOKE_WDT
>  +    bool "Book E(PowerPC 4xx/e500) Watchdog Timer"
>  +    depends on WATCHDOG && ( 4xx || E500 )
>  +    ---help---
>  +      This is the driver for the watchdog timers on
>  +      PowerPC 4xx and PowerPC e500.
>  +
>    # MIPS Architecture
>
>   config INDYDOG
>  --- linux-2.6.11/drivers/char/watchdog/Makefile 2005-03-04  
> 17:15:30.582965496 +0900
>  +++ linux-2.6.11-booke-wdt/drivers/char/watchdog/Makefile        
> 2005-03-04 13:21:32.000000000 +0900
>  @@ -39,3 +39,4 @@ obj-$(CONFIG_USBPCWATCHDOG) += pcwd_usb.
>    obj-$(CONFIG_IXP4XX_WATCHDOG) += ixp4xx_wdt.o
>    obj-$(CONFIG_IXP2000_WATCHDOG) += ixp2000_wdt.o
>   obj-$(CONFIG_8xx_WDT) += mpc8xx_wdt.o
>  +obj-$(CONFIG_BOOKE_WDT) += booke_wdt.o
>  --- linux-2.6.11/drivers/char/watchdog/booke_wdt.c      1970-01-01  
> 09:00:00.000000000 +0900
>  +++ linux-2.6.11-booke-wdt/drivers/char/watchdog/booke_wdt.c     
> 2005-03-04 16:38:58.000000000 +0900
>  @@ -0,0 +1,664 @@
>  +/*
>  + *    Copyright (c) 2005 Fujitsu Limited
>  + *
>  + *    Module name: booke_wdt.c
>  + *    Author:      Takeharu KATO<kato.takeharu at jp.fujitsu.com>
> + *
>  + *    This program is free software; you can redistribute it and/or
>  + *    modify it under the terms of the GNU General Public License
> + *    as published by the Free Software Foundation; either version 2
>  + *    of the License, or (at your option) any later version.
>  + *
>  + *    Neither Takeharu KATO nor Fujitsu Ltd. admit liability nor  
> provide
>  + *    warranty for any of this software.
>  + *
>  + *    Description:
>  + *     Watchdog driver for PowerPC Book E (PowerPC 4xx series  
> processors and
>  + *     PowerPC e500 series processors).
>  + *     Derived from drivers/char/watchdog/wdt.c by Alan cox
>  + *              and  drivers/char/watchdog/ppc405_wdt.c by Armin  
> Kuster.
>  + *     PPC4xx WDT operation is driverd from Appendix of
>  + *     PowerPC Embedded Processors Application Note
>  + *      ``PowerPC 40x Watch Dog Timer'' published from IBM.
>  + *     This driver is written according to ``PowerPC e500 Core  
> Complex
>  + *     Reference Manual'' for e500 part.
>  + */
>  +#include <linux/config.h>
> +#include <linux/kernel.h>
> +#include <linux/types.h>
> +#include <linux/miscdevice.h>
> +#include <linux/watchdog.h>
> +#include <linux/fs.h>
>  +#include <linux/reboot.h>
> +#include <linux/init.h>
>  +#include <linux/capability.h>
> +#include <linux/string.h>
> +#include <linux/ptrace.h>
> +#include <asm/reg.h>
>  +#include <asm/uaccess.h>
> +#include <asm/system.h>
> +#include "booke_wdt.h"
> +
>  +/* micro seconds per one milli-second(used to calculatewatchdog
> + * counter to be set). */
>  +#define US_PER_MS 1000
>  +/*  Calculate watchdog count   */
>  +#define calculate_wdt_count(t) ((((unsigned long)(t))*HZ)/1000)
> +
>  +int wdt_enable=0;             /* WDT start on boot  */
>  +int wdt_period=WDT_TIMO;       /* Time out in ms */
>  +
>  +#ifdef CONFIG_WATCHDOG_NOWAYOUT
> +static int nowayout = 1;
>  +#else
>  +static int nowayout = 0;
>  +#endif
>  +
>  +/*
>  + * Global variables
>  + */
>  +static int wdt_count = 0;            /* WDT intrrupt counter to be  
> reloaded */
>  +static volatile int wdt_heartbeat_count = 0;  /* WDT intrrupt  
> counter(compatible mode)*/
>  +static unsigned long driver_state; /* Driver status (see:  
> booke_wdt.h) */
>  +/*
>  + *  Identifier for this watchdog
>  + */
>  +static struct watchdog_info ident = {
>  +  .options=WDIOF_SETTIMEOUT|WDIOF_KEEPALIVEPING|WDIOF_MAGICCLOSE,
> +  .firmware_version =    0, /*  This is filled with PVR in  
> initialization. */
>  +  .identity =        "Book E(PPC 4xx/e500) WDT",
>  +};
>  +
>  +/*
>  + *  PowerPC Linux common exception handler
>  + */
>  +extern void _exception(int signr, struct pt_regs *regs, int code,  
> unsigned long addr);
>  +/*  Panic notifier  */
>  +extern struct notifier_block *panic_notifier_list;
> +/*
>  + *  External linkage functions
>  + */
>  +void booke_wdt_heartbeat(void);
> +void booke_wdt_setup_options(char *cmd_line);
>  +void booke_wdt_exception(struct pt_regs *regs);
> +/*
>  + * Internal linkage functions
>  + */
>  +static __inline__ void __booke_wdt_setup_val(int period,int reset);
>  +static __inline__ void __booke_wdt_enable(void);
> +static __inline__ void __booke_wdt_disable(void);
> +static __inline__ int  __booke_wdt_is_enabled(void);
> +static __inline__ void __booke_wdt_clear_int_stat(void);
> +static __inline__ void __booke_wdt_set_timeout(int t);
>  +static __inline__ void booke_wdt_init_device(void);
> +static __inline__ int  booke_wdt_is_enabled(void);
> +static __inline__ int  booke_wdt_start(void);
> +static __inline__ int  booke_wdt_stop(void);
> +static __inline__ int  booke_wdt_ping(void);
> +static __inline__ int  booke_wdt_set_timeout(int t);
>  +static __inline__ int  booke_wdt_get_status(int *status);
>  +static ssize_t booke_wdt_write(struct file *file, const char *buf,  
> size_t count, loff_t *ppos);
>  +static int booke_wdt_ioctl(struct inode *inode, struct file *file,  
> unsigned int cmd,unsigned long arg);
>  +static int booke_wdt_open(struct inode *inode, struct file *file);
> +static int booke_wdt_release(struct inode *inode, struct file *file);
> +static int booke_wdt_notify_sys(struct notifier_block *this, unsigned  
> long code,void *unused);
>  +static int __init booke_wdt_init(void);
> +static void __exit booke_wdt_exit(void);
> +
>  +/*
>  + *    Watchdog operations on PPC4xx/e500 MPU
>  + */
>  +
>  +/**
>  + *      __booke_wdt_setup_val
> + *      Enable Watchdog, sets up passed in values for TCR[WP],
>  + *      TCR[WRC]
>  + *
>  + *    @period:    Input Watchdog Period - TCR[WP]
>  + *                      0 = 217 clocks
> + *                      1 = 221 clocks
> + *                      2 = 225 clocks
> + *                      3 = 229 clocks
> + *      @reset:         Watchdog reset control - TCR[WRC]
>  + *                      0 = No reset
>  + *                      1 = PPC Core reset only
>  + *                      2 = PPC Chip reset
>  + *                      3 = System reset
>  + *     Note: The meaning of period number is differ PPC440GP from  
> PPC440GX.
>  + */
>  +#if defined(CONFIG_4xx)
> +static __inline__ void
> +__booke_wdt_setup_val(int period,int reset)
>  +{
>  +  unsigned long val;
>  +
>  +  /*  Set up TCR  */
>> val=((period)<<WDT_TCR_WP_SHIFT|(reset)<<WDT_TCR_WRC_SHIFT)|mfspr(SPRN_ 
> TCR);
> +  /*  Disable WDT  */
>  +  val &= ~(WDT_TCR_WDT_ENABLE);
> +
>  +  mtspr(SPRN_TCR,val);
> +}
>  +#else
>  +/*  e500  */
>  +static __inline__ void
> +__booke_wdt_setup_val(int period,int reset)
>  +{
>  +  unsigned long val;
>  +  /*  Set up TCR  */
>  +
>  +  val=(((period)&(WDT_TCR_WP_BITMSK)) << WDT_TCR_WP_SHIFT|
> +       ( ( (period) >> 2 )&(WDT_TCR_WPEXT_BITMSK)) <<  
> WDT_TCR_WPEXT_SHIFT|
> +       (reset)<<WDT_TCR_WRC_SHIFT)|mfspr(SPRN_TCR);
> +  /*  Disable WDT  */
>  +  val &= ~(WDT_TCR_WDT_ENABLE);
> +
>  +  mtspr(SPRN_TCR,val);
> +}
>  +#endif  /*  CONFIG_E500 */
>  +/**
>  + *      __booke_wdt_enable
> + *      Enable Watchdog
>  + */
>  +static __inline__ void
> +__booke_wdt_enable(void)
> +{
>  +  mtspr(SPRN_TCR,(mfspr(SPRN_TCR)|WDT_TCR_WDT_ENABLE));
> +}
>  +/**
>  + *      __booke_wdt_disable
> + *      Disable Watchdog
>  + */
>  +static __inline__ void
> +__booke_wdt_disable(void)
> +{
>  +  mtspr(SPRN_TCR,(mfspr(SPRN_TCR)&(~(WDT_TCR_WDT_ENABLE))));
> +}
>  +/**
>  + *      __booke_wdt_is_enabled
> + *      Check whether Watchdog is enabled.
>  + */
>  +static __inline__ int
>  +__booke_wdt_is_enabled(void)
> +{
>  +  return (mfspr(SPRN_TCR) & WDT_TCR_WDT_ENABLE);
> +}
>  +/**
>  + *      __booke_wdt_clear_init_stat
> + *      Clear interrupt status of watchdog to ping it.
>  + */
>  +static __inline__ void
> +__booke_wdt_clear_int_stat(void)
> +{
>  +  mtspr(SPRN_TSR, (TSR_ENW|TSR_WIS));
> +}
>  +/**
>  + *    __booke_wdt_set_timeout:
> + *    @t:    the new time out value that needs to be set.
>  + *
>  + *    Set a new time out value for the watchdog device.
>  + *
>  + */
>  +static __inline__ void
> +__booke_wdt_set_timeout(int t)
>  +{
>  +  wdt_count=calculate_wdt_count(t);
> +  return;
>  +}
>  +
>  +/*
>  + * Driver specific functions
>  + */
>  +
>  +/**
>  + *   booke_wdt_setup_options
> + *   @cmd_line : a pointer to kernel command line.
> + *
>  + */
>  +void
>  +booke_wdt_setup_options(char *cmd_line)
>  +{
>  +/*
>  + * Look for wdt= option on command line
>  + */
>  +  if (strstr(cmd_line, "wdt=")) {
>  +    int valid_wdt = 0;
>  +    char *p, *q;
> +
>  +    for (q = cmd_line; (p = strstr(q, "wdt=")) != 0;) {
> +      q = p + 4;
> +      if (p > cmd_line && p[-1] != ' ')
>  +    continue;
>  +      wdt_period = simple_strtoul(q, &q, 0);
>  +      valid_wdt = 1;
>  +      ++q;
>  +    }
>  +    wdt_enable = valid_wdt;
>  +  }
>  +  return;
>  +}
>  +/**
>  + *    booke_wdt_heartbeat:
> + *      Ping routine called from kernel.
>  + */
>  +void
>  +booke_wdt_heartbeat(void)
> +{
>  +  /* Disable watchdog */
>  +  __booke_wdt_disable();
> +
>  +  /* Write a watchdog value */
>  +  __booke_wdt_clear_int_stat();
> +
>  +  if (!wdt_enable)
>  +    goto out;
>  +
>  +  if  (wdt_heartbeat_count > 0)
>  +    wdt_heartbeat_count--;
>  +  else
>  +    panic(booke_mkmsg("Initiating system reboot.\n"));
>  +
>  +  /* Enable watchdog */
>  +  __booke_wdt_enable();
> + out:
>  +  /*  Reset count  */
>  +  ppc_md.heartbeat_count = 0;
>  +}
>  +/**
>  + *    booke_wdt_exception:
> + *      WatchDog Exception handler for PPC4xx/e500.
> + *      @regs : A registers information.
>  + */
>  +void
>  +booke_wdt_exception(struct pt_regs *regs)
>  +{
>  +  wdt_enable=0;
> +  __booke_wdt_disable();
> +  printk("WDT Exception at PC: %lx, MSR: %lx, vector=%lx    %s\n",
>  +        regs->nip, regs->msr, regs->trap, print_tainted());
> +  panic(booke_mkmsg("Initiating system reboot.\n"));
>  +}
>  +/*
>  + *    Driver Logic functions
> + */
>  +static __inline__ int
>  +booke_wdt_is_enabled(void)
> +{
>  +  return  __booke_wdt_is_enabled();
> +}
>  +/**
>  + *    booke_wdt_start:
> + *
>  + *    Start the watchdog driver.
>  + */
>  +static __inline__ int
>  +booke_wdt_start(void)
> +{
>  +  __booke_wdt_enable();
> +  return 0;
>  +}
>  +
>  +/**
>  + *    booke_wdt_stop:
> + *
>  + *    Stop the watchdog driver.
>  + */
>  +static __inline__ int
>  +booke_wdt_stop (void)
>  +{
>  +  __booke_wdt_disable();
> +  return 0;
>  +}
>  +/**
>  + *    booke_wdt_ping:
> + *
>  + *    Reload counter one with the watchdog heartbeat. We don't  
> bother reloading
>  + *    the cascade counter.
>  + */
>  +static __inline__ int
>  +booke_wdt_ping(void)
> +{
>  +  /* Disable watchdog */
>  +  __booke_wdt_disable();
> +  /* Write a watchdog value */
>  +  __booke_wdt_clear_int_stat();
> +  /*  Reset count  */
>  +  wdt_heartbeat_count=wdt_count;
> +  /* Enable watchdog */
>  +  __booke_wdt_enable();
> +
>  +  return 0;
>  +}
>  +/**
>  + *    booke_wdt_set_timeout:
> + *    @t:        the new timeout value that needs to be set.
>  + *
>  + *    Set a new time out value for the watchdog device.
>  + *      If the heartbeat value is incorrect we keep the old value
>  + *      and return -EINVAL. If successfull we return 0.
>  + */
>  +static __inline__ int
>  +booke_wdt_set_timeout(int t)
>  +{
>  +  if ((t < WDT_HEARTBEAT_MIN) || (t > WDT_HEARTBEAT_MAX))
> +    return -EINVAL;
>  +
>  +  wdt_period = t;
>  +  __booke_wdt_set_timeout(t);
> +  wdt_heartbeat_count=wdt_count;
> +  booke_wdt_dbg("The WDT counter set %d.\n",wdt_count);
> +
>  +  return 0;
>  +}
>  +
>  +/**
>  + *    booke_wdt_get_status:
> + *    @status: the new status.
>  + *
>  + *    Return the enable/disable card status.
>  + */
>  +static __inline__ int
>  +booke_wdt_get_status(int *status)
>  +{
>  +  if (wdt_enable)
>  +      *status = WDIOS_ENABLECARD;
> +  else
>  +      *status = WDIOS_DISABLECARD;
> +
>  +  return 0;
>  +}
>  +/*
>  + *    Kernel Interfaces
>  + */
>  +/**
>  + *    booke_wdt_init_device:
> + *
>  + *      Initilize PowerPC 4xx/e500 family Watch Dog facility.
>  + */
>  +static void
>  +booke_wdt_init_device(void)
> +{
>  +        /* Hardware WDT provided by the processor.
>  +     * So, we set firmware version as processor version number.
>  +     */
>  +    ident.firmware_version=mfspr(PVR);
> +    __booke_wdt_setup_val(WDT_WP,WDT_RESET_NONE);
> +}
>  +/**
>  + *    booke_wdt_write:
> + *    @file: file handle to the watchdog
>  + *    @buf: buffer to write (unused as data does not matter here
>  + *    @count: count of bytes
>  + *    @ppos: pointer to the position to write. No seeks allowed
>  + *
>  + *    A write to a watchdog device is defined as a keepalive signal.  
> Any
>  + *    write of data will do, as we we don't define content meaning  
> expept
>  + *      'V' character. It is performed as a sign to set  
> stop-on-close mode.
>  + */
>  +
>  +static ssize_t
>  +booke_wdt_write(struct file *file, const char *buf, size_t count,  
> loff_t *ppos)
>  +{
>  +  size_t i;
>  +
>  +    if (!nowayout) {
>  +      /* In case it was set long ago */
>  +      clear_bit(WDT_STATE_STOP_ON_CLOSE, &driver_state);
> +
>  +      for (i = 0; i < count; i++) {
> +    char c;
>  +
>  +    if (get_user(c, buf + i))
>  +      return -EFAULT;
>  +
>  +    if (c == 'V') {
>  +      set_bit(WDT_STATE_STOP_ON_CLOSE, &driver_state);
> +    }
>  +      }
>  +    }
>  +    booke_wdt_ping();
> +
>  +  return count;
>  +}
>  +
>  +/**
>  + *    booke_wdt_ioctl:
> + *    @inode: inode of the device
>  + *    @file: file handle to the device
>  + *    @cmd: watchdog command
>  + *    @arg: argument pointer
>  + *
>  + */
>  +static int
>  +booke_wdt_ioctl(struct inode *inode, struct file *file, unsigned int  
> cmd,
>  +    unsigned long arg)
>  +{
>  +    int new_timeout;
>  +    int status;
>  +
>  +    if (!capable(CAP_SYS_ADMIN))
> +        return -EPERM;  /*  It may be too strict manner.  */
>  +    switch(cmd)
>  +    {
>  +    default:
>  +        return -ENOIOCTLCMD;
> +    case WDIOC_GETSUPPORT:
> +        if (copy_to_user((struct watchdog_info *)arg, &ident,  
> sizeof(struct watchdog_info)))
> +            return -EFAULT;
>  +        else
>  +            break;
>  +    case WDIOC_GETSTATUS:
> +        booke_wdt_get_status(&status);
> +        return put_user(status,(int *)arg);
>  +    case WDIOC_KEEPALIVE:
> +        booke_wdt_ping();
> +        break;
>  +    case WDIOC_SETTIMEOUT:
> +        if (get_user(new_timeout, (int *)arg))
>  +            return -EFAULT;
>  +        if (booke_wdt_set_timeout(new_timeout))
> +            return -EINVAL;
>  +        booke_wdt_ping();
> +        break;
>  +    case WDIOC_GETTIMEOUT:
> +        return put_user(wdt_period, (int *)arg);
>  +    case WDIOC_SETOPTIONS:
> +        if (get_user(status, (int *)arg))
>  +            return -EFAULT;
>  +        /*  Return -EINVAL when the driver can not figure out
>  +         *  what it should do. Unknown cases are just ignored.
>  +         */
>  +        if ( (status & (WDIOS_DISABLECARD|WDIOS_ENABLECARD))
> +             == (WDIOS_DISABLECARD|WDIOS_ENABLECARD) )
>  +            return -EINVAL;
>  +        if (status & WDIOS_DISABLECARD) {
>  +            wdt_enable = 0;
>  +            booke_wdt_stop();
> +            booke_wdt_info("Watchdog timer is disabled\n");
>  +        }
>  +        if (status & WDIOS_ENABLECARD) {
>  +            wdt_enable = 1;
>  +            booke_wdt_start();
> +            booke_wdt_info("Watchdog timer is enabled\n");
>  +        }
>  +        break;
>  +    }
>  +    return 0;
>  +}
>  +/**
>  + *    booke_wdt_open:
> + *    @inode: inode of device
>  + *    @file: file handle to device
>  + *
>  + *    The watchdog device has been opened. The watchdog device is  
> single
> + *    open and start the WDT timer.
>  + */
>  +static int
>  +booke_wdt_open(struct inode *inode, struct file *file)
>  +{
>  +    if (!capable(CAP_SYS_ADMIN))
> +        return -EPERM;
>  +
>  +    if (test_and_set_bit(WDT_STATE_OPEN, &driver_state))
> +        return -EBUSY;
>  +    /*
>  +     * Activate
>  +     */
>  +    booke_wdt_start();
> +    wdt_enable=1;
> +
>  +    if (nowayout)
>  +      set_bit(WDT_STATE_STOP_ON_CLOSE, &driver_state);
> +
>  +    return 0;
>  +}
>  +
>  +/**
>  + *    booke_wdt_release:
> + *    @inode: inode to board
> + *    @file: file handle to board
>  + *
>  + */
>  +static int
>  +booke_wdt_release(struct inode *inode, struct file *file)
>  +{
>  +  if (test_bit(WDT_STATE_STOP_ON_CLOSE, &driver_state)) {
>  +      booke_wdt_note("WDT device is stopped.\n");
>  +    booke_wdt_stop();
> +    wdt_enable=0;
> +  } else {
>  +    if ( (booke_wdt_is_enabled()) && (!nowayout) ) {
>  +      booke_wdt_note("WDT device may be closed unexpectedly.  WDT  
> will not stop!\n");
>  +      booke_wdt_ping();
> +    }
>  +  }
>  +  clear_bit(WDT_STATE_OPEN, &driver_state);
> +
>  +  return 0;
>  +}
>  +/**
>  + *    notify_sys:
>  + *    @this: our notifier block
>  + *    @code: the event being reported
> + *    @unused: unused
>  + *    Note: This function assume that the panic notifier is called  
> with CODE=0
>  + *          (see panic function in kernel/panic.c).
> + */
>  +static int
>  +booke_wdt_notify_sys(struct notifier_block *this, unsigned long code,
>  +    void *unused)
>  +{
>  +
>  +    if (code != SYS_POWER_OFF)   /* Turn the card off */
>  +      booke_wdt_stop();
> +
>  +    return NOTIFY_DONE;
> +}
>  +
>  +static struct file_operations booke_wdt_fops = {
>  +    .owner        = THIS_MODULE,
> +    .llseek        = no_llseek,
>  +    .write        = booke_wdt_write,
> +    .ioctl        = booke_wdt_ioctl,
> +    .open        = booke_wdt_open,
> +    .release    = booke_wdt_release,
> +};
>  +
>  +static struct miscdevice booke_wdt_miscdev = {
>  +    .minor    = WATCHDOG_MINOR,
> +    .name    = "watchdog",
>  +    .fops    = &booke_wdt_fops,
> +};
>  +
>  +/*
>  + *    The WDT card needs to know about shutdowns in order to
>  + *    turn WDT off.
>  + */
>  +
>  +static struct notifier_block booke_wdt_notifier = {
>  +    .notifier_call = booke_wdt_notify_sys,
> +};
>  +
>  +/**
>  + *    cleanup_module:
> + *
>  + *    If your watchdog is set to continue ticking on close and you  
> unload
>  + *    it, well it keeps ticking.  You just have to load a new
>  + *    module in 60 seconds or reboot.
>  + *      This behavior(more over the comments as above) is borrowed  
> from
>  + *      Alan cox's driver.
>  + */
>  +
>  +static void __exit
>  +booke_wdt_exit(void)
> +{
>  +    misc_deregister(&booke_wdt_miscdev);
> +    unregister_reboot_notifier(&booke_wdt_notifier);
> +     
> notifier_chain_unregister(&panic_notifier_list,&booke_wdt_notifier);
> +}
>  +
>  +/**
>  + *     booke_wdt_init:
> + *
>  + *    Set up the WDT relevant timer facility.
>  + */
>  +
>  +static int __init
>  +booke_wdt_init(void)
> +{
>  +    int ret;
>  +    unsigned long flags;
>  +
>  +    ret = register_reboot_notifier(&booke_wdt_notifier);
> +    if(ret) {
>  +      booke_wdt_err("Cannot register reboot notifier (err=%d)\n",  
> ret);
>  +      return ret;
> +    }
>  +
>  +    /* Register panic notifier  */
>  +    ret =  
> notifier_chain_register(&panic_notifier_list,&booke_wdt_notifier);
> +    if(ret) {
>  +      booke_wdt_err("Cannot register panic notifier (err=%d)\n",  
> ret);
>  +      unregister_reboot_notifier(&booke_wdt_notifier);
> +      return ret;
> +    }
>  +
>  +    ret = 0;
>  +    booke_wdt_init_device();
> +    /* Check that the heartbeat value is within it's range ; if not  
> reset to the default */
>  +    if (booke_wdt_set_timeout(wdt_period)) {
>  +      if (wdt_period)
>  +        booke_wdt_info("The heartbeat value must be %d < wdt_period  
> < %d, using
> %d\n",WDT_HEARTBEAT_MIN,WDT_HEARTBEAT_MAX,WDT_TIMO);
> +      booke_wdt_set_timeout(WDT_TIMO);
> +    }
>  +
>  +    local_irq_save(flags); /* Prevent timer interrupt */
>  +    ppc_md.heartbeat_count = 0;
>  +    ppc_md.heartbeat=booke_wdt_heartbeat;
> +    local_irq_restore(flags);
> +
>  +    booke_wdt_info("Book E(PPC 4xx/e500) Watchdog Driver. period=%d  
> ms (nowayout=%d)\n",wdt_period,
>  nowayout);
>  +
>  +    ret = misc_register(&booke_wdt_miscdev);
> +    if (ret) {
>  +      booke_wdt_err("Cannot register miscdev on minor=%d (err=%d)\n",
>  +            WATCHDOG_MINOR, ret);
>  +        goto outmisc;
>  +    }
>  +
>  +    if (wdt_enable) {
>  +      booke_wdt_info("WDT start on boot.\n");
>  +      booke_wdt_start();
> +    }
>  +out:
>  +    return ret;
>  +outmisc:
>  +    unregister_reboot_notifier(&booke_wdt_notifier);
> +    local_irq_save(flags);
> +    ppc_md.heartbeat=NULL;
> +    ppc_md.heartbeat_count = 0;
>  +    local_irq_restore(flags);
> +    goto out;
>  +}
>  +
>  +device_initcall(booke_wdt_init);
> --- linux-2.6.11/drivers/char/watchdog/booke_wdt.h      1970-01-01  
> 09:00:00.000000000 +0900
>  +++ linux-2.6.11-booke-wdt/drivers/char/watchdog/booke_wdt.h     
> 2005-03-04 16:38:58.000000000 +0900
>  @@ -0,0 +1,125 @@
>  +/*
>  + *
>  + *    Copyright (c) 2004 Fujitsu Limited
>  + *
>  + *    Module name: booke_wdt.h
>  + *    Author:      Takeharu KATO<kato.takeharu at jp.fujitsu.com>
> + *    Description:
>  + *      Header file for PowerPC Book E(PPC 4xx/e500) watchdog driver.
>  + *
>  + *    This program is free software; you can redistribute it and/or
>  + *    modify it under the terms of the GNU General Public License
> + *    as published by the Free Software Foundation; either version 2
>  + *    of the License, or (at your option) any later version.
>  + *
>  + *    Neither Takeharu KATO nor Fujitsu Ltd. admit liability nor  
> provide
>  + *    warranty for any of this software.
>  + *
>  + */
>  +#ifndef _DRIVERS_CHAR_WATCHDOG_BOOKE_WDT_H
> +#define _DRIVERS_CHAR_WATCHDOG_BOOKE_WDT_H
> +#include <linux/config.h>
> +#include <linux/kernel.h>
> +#include <linux/ptrace.h>
> +#include <linux/watchdog.h>
> +
>  +/*
>  + *  Driver state flags(bit position)
>  + */
>  +#define WDT_STATE_OPEN                  0   /* driver is opend  */
>  +#define WDT_STATE_STOP_ON_CLOSE         1   /* Stop with close is  
> expected */
>  +/*
>  + * Configurations
> + */
>  +#define WDT_TIMO           60000    /* Default timeout = 60000  
> ms(1min) */
>  +#define WDT_HEARTBEAT_MIN  100          /* Minimum timeout = 100 ms  
> */
>  +#define WDT_HEARTBEAT_MAX  600000       /* Maximum timeout =  
> 600000ms(1hour) */
>  +#ifdef __KERNEL__
>  +//#define BOOKE_WDT_DEBUG                     /*  Debug switch */
>  +/*
>  + *  Reset type
> + */
>  +#define WDT_RESET_NONE     0
>  +#define WDT_RESET_CORE     1
>  +#define WDT_RESET_CHIP     2
>  +#define WDT_RESET_SYS      3
>  +/*
>  + *   Bit positions in  TCR register on PPC4xx/e500 series.
>  + */
>  +#define WDT_TCR_WP_BIT     1   /*  WP  bit in TCR (bit[0..1])   */
>  +#define WDT_TCR_WRC_BIT    3   /*  WRC bit in TCR (bit[2..3])   */
>  +#define WDT_TCR_WIE_BIT    4   /*  WIE bit in TCR (bit[4])      */
>  +/*
>  + *  TCR[WP] relevant definitions
>  + */
>  +#define WDT_TCR_WP_SHIFT       (31 - WDT_TCR_WP_BIT)
> +#define WDT_TCR_WRC_SHIFT      (31 - WDT_TCR_WRC_BIT)
> +#define WDT_TCR_WIE_SHIFT      (31 - WDT_TCR_WIE_BIT)
> +#define WDT_TCR_WDT_ENABLE     (1<<WDT_TCR_WIE_SHIFT)
> +/*  MASK value to obatain TCR[WP]  */
>  +#define WDT_TCR_WP_MASK        (3<<(WDT_TCR_WP_SHIFT))
> +
>  +/*  Watchdog timer periods can be set on PPC 4xx cpus. */
>  +#if defined(CONFIG_4xx)
> +/*
>  + *  For PowerPC 4xx
>  + */
>  +#define WDT_WP0               0
>  +#define WDT_WP1               1
>  +#define WDT_WP2               2
>  +#define WDT_WP3               3
>  +#else
>  +#if defined(CONFIG_E500)
> +/*
>  + *  For e500 CPU
>  + *  Actually, e500 can arbitrary periods can be set,
>  + *  But this driver uses fix period value as same as PPC440
>  + *  on purpose for simplicity.
>  + *  Following values split into WP and WP_EXT parts in booke_wdt.c.
>  + */
>  +#define WDT_WP0               21
>  +#define WDT_WP1               25
>  +#define WDT_WP2               29
>  +#define WDT_WP3               33
>  +#define WDT_TCR_WP_BITMSK     0x3  /*  2bit length  */
>  +#define WDT_TCR_WPEXT_BITMSK  0xf  /*  4bit length  */
>  +#define WDT_TCR_WPEXT_SHIFT  17
>  +#else
>  +#error "Book E WDT detects invalid configuration(Unknown CPU)"
>  +#endif  /*  CONFIG_E500  */
>  +#endif  /*  CONFIG_4xx   */
>  +/*
>  + *  WP relevant values used in our driver.
>  + *  Note:WDT period must be more than HZ(Timer ticks)
> + */
>  +#define WDT_WP                 WDT_WP3
>  +
>  +/*
>  + *  IOCTL commands for comaptiblity for old driver
>  + */
>  +#define WDIOC_GETPERIOD         WDIOC_GETTIMEOUT
> +#define WDIOC_SETPERIOD         WDIOC_SETTIMEOUT
> +
>  +/*
>  + *  output messages
>  + */
>  +#define __BOOKE_WDT_MSG "BookE-WDT : "
>  +#define booke_mkmsg(str) __BOOKE_WDT_MSG str
>  +#define booke_wdt_info(fmt,arg...) \
>  +    printk(KERN_INFO __BOOKE_WDT_MSG fmt,##arg)
>  +#define booke_wdt_note(fmt,arg...) \
>  +    printk(KERN_NOTICE __BOOKE_WDT_MSG fmt,##arg)
>  +#define booke_wdt_err(fmt,arg...) \
>  +    printk(KERN_ALERT __BOOKE_WDT_MSG fmt,##arg)
>  +#define booke_wdt_crit(fmt,arg...) \
>  +    printk(KERN_ALERT __BOOKE_WDT_MSG fmt,##arg)
>  +#if defined(BOOKE_WDT_DEBUG)
> +#define booke_wdt_dbg(fmt,arg...) \
>  +    printk(KERN_ALERT __BOOKE_WDT_MSG fmt,##arg)
>  +#else
>  +#define booke_wdt_dbg(fmt,arg...) \
>  +        do{}while(0)
>  +#endif  /*  WDT_DEBUG  */
>  +
>  +#endif  /* __KERNEL__  */
>  +#endif  /*  _DRIVERS_CHAR_WATCHDOG_BOOKE_WDT_H  */
>
>  



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