+++ /dev/null
-// 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)
-{
- bcm63xx_wdt_pet();
- bcm63xx_timer_tick(0);
-}
-
-static void bcm63xx_wdt_pause(void)
-{
- del_timer_sync(&bcm63xx_wdt_device.timer);
- bcm63xx_wdt_hw_stop();
-}
-
-static int bcm63xx_wdt_settimeout(int new_time)
-{
- if ((new_time <= 0) || (new_time > WDT_MAX_TIME))
- return -EINVAL;
-
- wdt_time = new_time;
-
- return 0;
-}
-
-static int bcm63xx_wdt_open(struct inode *inode, struct file *file)
-{
- if (test_and_set_bit(0, &bcm63xx_wdt_device.inuse))
- return -EBUSY;
-
- bcm63xx_wdt_start();
- return stream_open(inode, file);
-}
-
-static int bcm63xx_wdt_release(struct inode *inode, struct file *file)
-{
- if (expect_close == 42)
- bcm63xx_wdt_pause();
- else {
- pr_crit("Unexpected close, not stopping watchdog!\n");
- bcm63xx_wdt_start();
- }
- clear_bit(0, &bcm63xx_wdt_device.inuse);
- expect_close = 0;
- return 0;
-}
-
-static ssize_t bcm63xx_wdt_write(struct file *file, const char *data,
- size_t len, loff_t *ppos)
-{
- if (len) {
- if (!nowayout) {
- size_t i;
-
- /* In case it was set long ago */
- expect_close = 0;
-
- for (i = 0; i != len; i++) {
- char c;
- if (get_user(c, data + i))
- return -EFAULT;
- if (c == 'V')
- expect_close = 42;
- }
- }
- bcm63xx_wdt_pet();
- }
- return len;
-}
-
-static struct watchdog_info bcm63xx_wdt_info = {
- .identity = PFX,
- .options = WDIOF_SETTIMEOUT |
- WDIOF_KEEPALIVEPING |
- WDIOF_MAGICCLOSE,
-};
-
-
-static long bcm63xx_wdt_ioctl(struct file *file, unsigned int cmd,
- unsigned long arg)
-{
- void __user *argp = (void __user *)arg;
- int __user *p = argp;
- int new_value, retval = -EINVAL;
-
- switch (cmd) {
- case WDIOC_GETSUPPORT:
- return copy_to_user(argp, &bcm63xx_wdt_info,
- sizeof(bcm63xx_wdt_info)) ? -EFAULT : 0;
-
- case WDIOC_GETSTATUS:
- case WDIOC_GETBOOTSTATUS:
- return put_user(0, p);
-
- case WDIOC_SETOPTIONS:
- if (get_user(new_value, p))
- return -EFAULT;
-
- if (new_value & WDIOS_DISABLECARD) {
- bcm63xx_wdt_pause();
- retval = 0;
- }
- if (new_value & WDIOS_ENABLECARD) {
- bcm63xx_wdt_start();
- retval = 0;
- }
-
- return retval;
-
- case WDIOC_KEEPALIVE:
- bcm63xx_wdt_pet();
- return 0;
-
- case WDIOC_SETTIMEOUT:
- if (get_user(new_value, p))
- return -EFAULT;
-
- if (bcm63xx_wdt_settimeout(new_value))
- return -EINVAL;
-
- bcm63xx_wdt_pet();
-
- fallthrough;
-
- case WDIOC_GETTIMEOUT:
- return put_user(wdt_time, p);
-
- default:
- return -ENOTTY;
-
- }
-}
-
-static const struct file_operations bcm63xx_wdt_fops = {
- .owner = THIS_MODULE,
- .llseek = no_llseek,
- .write = bcm63xx_wdt_write,
- .unlocked_ioctl = bcm63xx_wdt_ioctl,
- .compat_ioctl = compat_ptr_ioctl,
- .open = bcm63xx_wdt_open,
- .release = bcm63xx_wdt_release,
-};
-
-static struct miscdevice bcm63xx_wdt_miscdev = {
- .minor = WATCHDOG_MINOR,
- .name = "watchdog",
- .fops = &bcm63xx_wdt_fops,
-};
-
-
-static int bcm63xx_wdt_probe(struct platform_device *pdev)
-{
- int ret;
- struct resource *r;
-
- timer_setup(&bcm63xx_wdt_device.timer, bcm63xx_timer_tick, 0);
-
- r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- if (!r) {
- dev_err(&pdev->dev, "failed to get resources\n");
- return -ENODEV;
- }
-
- bcm63xx_wdt_device.regs = devm_ioremap(&pdev->dev, r->start,
- resource_size(r));
- if (!bcm63xx_wdt_device.regs) {
- dev_err(&pdev->dev, "failed to remap I/O resources\n");
- return -ENXIO;
- }
-
- ret = bcm63xx_timer_register(TIMER_WDT_ID, bcm63xx_wdt_isr, NULL);
- if (ret < 0) {
- dev_err(&pdev->dev, "failed to register wdt timer isr\n");
- return ret;
- }
-
- if (bcm63xx_wdt_settimeout(wdt_time)) {
- bcm63xx_wdt_settimeout(WDT_DEFAULT_TIME);
- dev_info(&pdev->dev,
- ": wdt_time value must be 1 <= wdt_time <= 256, using %d\n",
- wdt_time);
- }
-
- ret = misc_register(&bcm63xx_wdt_miscdev);
- if (ret < 0) {
- dev_err(&pdev->dev, "failed to register watchdog device\n");
- goto unregister_timer;
- }
-
- dev_info(&pdev->dev, " started, timer margin: %d sec\n",
- WDT_DEFAULT_TIME);
-
- return 0;
-
-unregister_timer:
- bcm63xx_timer_unregister(TIMER_WDT_ID);
- return ret;
-}
-
-static int bcm63xx_wdt_remove(struct platform_device *pdev)
-{
- if (!nowayout)
- bcm63xx_wdt_pause();
-
- misc_deregister(&bcm63xx_wdt_miscdev);
- bcm63xx_timer_unregister(TIMER_WDT_ID);
- return 0;
-}
-
-static void bcm63xx_wdt_shutdown(struct platform_device *pdev)
-{
- bcm63xx_wdt_pause();
-}
-
-static struct platform_driver bcm63xx_wdt_driver = {
- .probe = bcm63xx_wdt_probe,
- .remove = bcm63xx_wdt_remove,
- .shutdown = bcm63xx_wdt_shutdown,
- .driver = {
- .name = "bcm63xx-wdt",
- }
-};
-
-module_platform_driver(bcm63xx_wdt_driver);
-
-MODULE_AUTHOR("Miguel Gaio <miguel.gaio@efixo.com>");
-MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
-MODULE_DESCRIPTION("Driver for the Broadcom BCM63xx SoC watchdog");
-MODULE_LICENSE("GPL");
-MODULE_ALIAS("platform:bcm63xx-wdt");
projects / platform / kernel / linux-rpi.git / commitdiff