+++ /dev/null
-// SPDX-License-Identifier: GPL-2.0-or-later
-/*
- * PNX833x Hardware Watchdog Driver
- * Copyright 2008 NXP Semiconductors
- * Daniel Laird <daniel.j.laird@nxp.com>
- * Andre McCurdy <andre.mccurdy@nxp.com>
- *
- * Heavily based upon - IndyDog 0.3
- * A Hardware Watchdog Device for SGI IP22
- *
- * (c) Copyright 2002 Guido Guenther <agx@sigxcpu.org>, All Rights Reserved.
- *
- * based on softdog.c by Alan Cox <alan@redhat.com>
- */
-
-#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-
-#include <linux/module.h>
-#include <linux/moduleparam.h>
-#include <linux/types.h>
-#include <linux/kernel.h>
-#include <linux/fs.h>
-#include <linux/mm.h>
-#include <linux/miscdevice.h>
-#include <linux/watchdog.h>
-#include <linux/notifier.h>
-#include <linux/reboot.h>
-#include <linux/init.h>
-#include <asm/mach-pnx833x/pnx833x.h>
-
-#define WATCHDOG_TIMEOUT 30 /* 30 sec Maximum timeout */
-#define WATCHDOG_COUNT_FREQUENCY 68000000U /* Watchdog counts at 68MHZ. */
-#define PNX_WATCHDOG_TIMEOUT (WATCHDOG_TIMEOUT * WATCHDOG_COUNT_FREQUENCY)
-#define PNX_TIMEOUT_VALUE 2040000000U
-
-/** CONFIG block */
-#define PNX833X_CONFIG (0x07000U)
-#define PNX833X_CONFIG_CPU_WATCHDOG (0x54)
-#define PNX833X_CONFIG_CPU_WATCHDOG_COMPARE (0x58)
-#define PNX833X_CONFIG_CPU_COUNTERS_CONTROL (0x1c)
-
-/** RESET block */
-#define PNX833X_RESET (0x08000U)
-#define PNX833X_RESET_CONFIG (0x08)
-
-static int pnx833x_wdt_alive;
-
-/* Set default timeout in MHZ.*/
-static int pnx833x_wdt_timeout = PNX_WATCHDOG_TIMEOUT;
-module_param(pnx833x_wdt_timeout, int, 0);
-MODULE_PARM_DESC(timeout, "Watchdog timeout in Mhz. (68Mhz clock), default="
- __MODULE_STRING(PNX_TIMEOUT_VALUE) "(30 seconds).");
-
-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) ")");
-
-#define START_DEFAULT 1
-static int start_enabled = START_DEFAULT;
-module_param(start_enabled, int, 0);
-MODULE_PARM_DESC(start_enabled, "Watchdog is started on module insertion "
- "(default=" __MODULE_STRING(START_DEFAULT) ")");
-
-static void pnx833x_wdt_start(void)
-{
- /* Enable watchdog causing reset. */
- PNX833X_REG(PNX833X_RESET + PNX833X_RESET_CONFIG) |= 0x1;
- /* Set timeout.*/
- PNX833X_REG(PNX833X_CONFIG +
- PNX833X_CONFIG_CPU_WATCHDOG_COMPARE) = pnx833x_wdt_timeout;
- /* Enable watchdog. */
- PNX833X_REG(PNX833X_CONFIG +
- PNX833X_CONFIG_CPU_COUNTERS_CONTROL) |= 0x1;
-
- pr_info("Started watchdog timer\n");
-}
-
-static void pnx833x_wdt_stop(void)
-{
- /* Disable watchdog causing reset. */
- PNX833X_REG(PNX833X_RESET + PNX833X_CONFIG) &= 0xFFFFFFFE;
- /* Disable watchdog.*/
- PNX833X_REG(PNX833X_CONFIG +
- PNX833X_CONFIG_CPU_COUNTERS_CONTROL) &= 0xFFFFFFFE;
-
- pr_info("Stopped watchdog timer\n");
-}
-
-static void pnx833x_wdt_ping(void)
-{
- PNX833X_REG(PNX833X_CONFIG +
- PNX833X_CONFIG_CPU_WATCHDOG_COMPARE) = pnx833x_wdt_timeout;
-}
-
-/*
- * Allow only one person to hold it open
- */
-static int pnx833x_wdt_open(struct inode *inode, struct file *file)
-{
- if (test_and_set_bit(0, &pnx833x_wdt_alive))
- return -EBUSY;
-
- if (nowayout)
- __module_get(THIS_MODULE);
-
- /* Activate timer */
- if (!start_enabled)
- pnx833x_wdt_start();
-
- pnx833x_wdt_ping();
-
- pr_info("Started watchdog timer\n");
-
- return stream_open(inode, file);
-}
-
-static int pnx833x_wdt_release(struct inode *inode, struct file *file)
-{
- /* Shut off the timer.
- * Lock it in if it's a module and we defined ...NOWAYOUT */
- if (!nowayout)
- pnx833x_wdt_stop(); /* Turn the WDT off */
-
- clear_bit(0, &pnx833x_wdt_alive);
- return 0;
-}
-
-static ssize_t pnx833x_wdt_write(struct file *file, const char *data, size_t len, loff_t *ppos)
-{
- /* Refresh the timer. */
- if (len)
- pnx833x_wdt_ping();
-
- return len;
-}
-
-static long pnx833x_wdt_ioctl(struct file *file, unsigned int cmd,
- unsigned long arg)
-{
- int options, new_timeout = 0;
- uint32_t timeout, timeout_left = 0;
-
- static const struct watchdog_info ident = {
- .options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT,
- .firmware_version = 0,
- .identity = "Hardware Watchdog for PNX833x",
- };
-
- switch (cmd) {
- default:
- return -ENOTTY;
-
- case WDIOC_GETSUPPORT:
- if (copy_to_user((struct watchdog_info *)arg,
- &ident, sizeof(ident)))
- return -EFAULT;
- return 0;
-
- case WDIOC_GETSTATUS:
- case WDIOC_GETBOOTSTATUS:
- return put_user(0, (int *)arg);
-
- case WDIOC_SETOPTIONS:
- if (get_user(options, (int *)arg))
- return -EFAULT;
-
- if (options & WDIOS_DISABLECARD)
- pnx833x_wdt_stop();
-
- if (options & WDIOS_ENABLECARD)
- pnx833x_wdt_start();
-
- return 0;
-
- case WDIOC_KEEPALIVE:
- pnx833x_wdt_ping();
- return 0;
-
- case WDIOC_SETTIMEOUT:
- {
- if (get_user(new_timeout, (int *)arg))
- return -EFAULT;
-
- pnx833x_wdt_timeout = new_timeout;
- PNX833X_REG(PNX833X_CONFIG +
- PNX833X_CONFIG_CPU_WATCHDOG_COMPARE) = new_timeout;
- return put_user(new_timeout, (int *)arg);
- }
-
- case WDIOC_GETTIMEOUT:
- timeout = PNX833X_REG(PNX833X_CONFIG +
- PNX833X_CONFIG_CPU_WATCHDOG_COMPARE);
- return put_user(timeout, (int *)arg);
-
- case WDIOC_GETTIMELEFT:
- timeout_left = PNX833X_REG(PNX833X_CONFIG +
- PNX833X_CONFIG_CPU_WATCHDOG);
- return put_user(timeout_left, (int *)arg);
-
- }
-}
-
-static int pnx833x_wdt_notify_sys(struct notifier_block *this,
- unsigned long code, void *unused)
-{
- if (code == SYS_DOWN || code == SYS_HALT)
- pnx833x_wdt_stop(); /* Turn the WDT off */
-
- return NOTIFY_DONE;
-}
-
-static const struct file_operations pnx833x_wdt_fops = {
- .owner = THIS_MODULE,
- .llseek = no_llseek,
- .write = pnx833x_wdt_write,
- .unlocked_ioctl = pnx833x_wdt_ioctl,
- .compat_ioctl = compat_ptr_ioctl,
- .open = pnx833x_wdt_open,
- .release = pnx833x_wdt_release,
-};
-
-static struct miscdevice pnx833x_wdt_miscdev = {
- .minor = WATCHDOG_MINOR,
- .name = "watchdog",
- .fops = &pnx833x_wdt_fops,
-};
-
-static struct notifier_block pnx833x_wdt_notifier = {
- .notifier_call = pnx833x_wdt_notify_sys,
-};
-
-static int __init watchdog_init(void)
-{
- int ret, cause;
-
- /* Lets check the reason for the reset.*/
- cause = PNX833X_REG(PNX833X_RESET);
- /*If bit 31 is set then watchdog was cause of reset.*/
- if (cause & 0x80000000) {
- pr_info("The system was previously reset due to the watchdog firing - please investigate...\n");
- }
-
- ret = register_reboot_notifier(&pnx833x_wdt_notifier);
- if (ret) {
- pr_err("cannot register reboot notifier (err=%d)\n", ret);
- return ret;
- }
-
- ret = misc_register(&pnx833x_wdt_miscdev);
- if (ret) {
- pr_err("cannot register miscdev on minor=%d (err=%d)\n",
- WATCHDOG_MINOR, ret);
- unregister_reboot_notifier(&pnx833x_wdt_notifier);
- return ret;
- }
-
- pr_info("Hardware Watchdog Timer for PNX833x: Version 0.1\n");
-
- if (start_enabled)
- pnx833x_wdt_start();
-
- return 0;
-}
-
-static void __exit watchdog_exit(void)
-{
- misc_deregister(&pnx833x_wdt_miscdev);
- unregister_reboot_notifier(&pnx833x_wdt_notifier);
-}
-
-module_init(watchdog_init);
-module_exit(watchdog_exit);
-
-MODULE_AUTHOR("Daniel Laird/Andre McCurdy");
-MODULE_DESCRIPTION("Hardware Watchdog Device for PNX833x");
-MODULE_LICENSE("GPL");
projects / platform / kernel / linux-starfive.git / commitdiff