linux-imx

// SPDX-License-Identifier: GPL-2.0+

/*

 *  Broadcom BCM63xx SoC watchdog driver

 *

 *  Copyright (C) 2007, Miguel Gaio <miguel.gaio@efixo.com>

 *  Copyright (C) 2008, Florian Fainelli <florian@openwrt.org>

 *

 */

​

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

​

#include <linux/bitops.h>

#include <linux/errno.h>

#include <linux/fs.h>

#include <linux/io.h>

#include <linux/kernel.h>

#include <linux/miscdevice.h>

#include <linux/module.h>

#include <linux/moduleparam.h>

#include <linux/types.h>

#include <linux/uaccess.h>

#include <linux/watchdog.h>

#include <linux/timer.h>

#include <linux/jiffies.h>

#include <linux/interrupt.h>

#include <linux/ptrace.h>

#include <linux/resource.h>

#include <linux/platform_device.h>

​

#include <bcm63xx_cpu.h>

#include <bcm63xx_io.h>

#include <bcm63xx_regs.h>

#include <bcm63xx_timer.h>

​

#define PFX KBUILD_MODNAME

​

#define WDT_HZ      50000000 /* Fclk */

#define WDT_DEFAULT_TIME    30      /* seconds */

#define WDT_MAX_TIME        256     /* seconds */

​

static struct {

    void __iomem *regs;

    struct timer_list timer;

    unsigned long inuse;

    atomic_t ticks;

} bcm63xx_wdt_device;

​

static int expect_close;

​

static int wdt_time = WDT_DEFAULT_TIME;

static bool nowayout = WATCHDOG_NOWAYOUT;

module_param(nowayout, bool, 0);

MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="

    __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");

​

/* HW functions */

static void bcm63xx_wdt_hw_start(void)

{

    bcm_writel(0xfffffffe, bcm63xx_wdt_device.regs + WDT_DEFVAL_REG);

    bcm_writel(WDT_START_1, bcm63xx_wdt_device.regs + WDT_CTL_REG);

    bcm_writel(WDT_START_2, bcm63xx_wdt_device.regs + WDT_CTL_REG);

}

​

static void bcm63xx_wdt_hw_stop(void)

{

    bcm_writel(WDT_STOP_1, bcm63xx_wdt_device.regs + WDT_CTL_REG);

    bcm_writel(WDT_STOP_2, bcm63xx_wdt_device.regs + WDT_CTL_REG);

}

​

static void bcm63xx_wdt_isr(void *data)

{

    struct pt_regs *regs = get_irq_regs();

​

    die(PFX " fire", regs);

}

​

static void bcm63xx_timer_tick(struct timer_list *unused)

{

    if (!atomic_dec_and_test(&bcm63xx_wdt_device.ticks)) {

        bcm63xx_wdt_hw_start();

        mod_timer(&bcm63xx_wdt_device.timer, jiffies + HZ);

    } else

        pr_crit("watchdog will restart system\n");

}

​

static void bcm63xx_wdt_pet(void)

{

    atomic_set(&bcm63xx_wdt_device.ticks, wdt_time);

}

​

static void bcm63xx_wdt_start(void)

{