[WATCHDOG] mpc83xx_wdt: add support for MPC86xx CPUs (500c919e) · Commits · 戴 / test

drivers/watchdog/Kconfig

+2 −2

Original line number	Diff line number	Diff line
		@@ -696,8 +696,8 @@ config 8xx_WDT
		depends on 8xx

		config 83xx_WDT
		tristate "MPC83xx Watchdog Timer"
		depends on PPC_83xx
		tristate "MPC83xx/MPC86xx Watchdog Timer"
		depends on PPC_83xx \|\| PPC_86xx

		config MV64X60_WDT
		tristate "MV64X60 (Marvell Discovery) Watchdog Timer"

drivers/watchdog/mpc83xx_wdt.c

+72 −8

Original line number	Diff line number	Diff line
		/*
		* mpc83xx_wdt.c - MPC83xx watchdog userspace interface
		* mpc83xx_wdt.c - MPC83xx/MPC86xx watchdog userspace interface
		*
		* Authors: Dave Updegraff <dave@cray.org>
		* Kumar Gala <galak@kernel.crashing.org>
		* Attribution: from 83xx_wst: Florian Schirmer <jolt@tuxbox.org>
		* ..and from sc520_wdt
		* Copyright (c) 2008 MontaVista Software, Inc.
		* Anton Vorontsov <avorontsov@ru.mvista.com>
		*
		* Note: it appears that you can only actually ENABLE or DISABLE the thing
		* once after POR. Once enabled, you cannot disable, and vice versa.
		@@ -18,6 +20,7 @@
		#include <linux/fs.h>
		#include <linux/init.h>
		#include <linux/kernel.h>
		#include <linux/timer.h>
		#include <linux/miscdevice.h>
		#include <linux/of_platform.h>
		#include <linux/module.h>
		@@ -39,6 +42,11 @@ struct mpc83xx_wdt {
		u8 res2[0xF0];
		};

		struct mpc83xx_wdt_type {
		int prescaler;
		bool hw_enabled;
		};

		static struct mpc83xx_wdt __iomem *wd_base;

		static u16 timeout = 0xffff;
		@@ -51,6 +59,11 @@ module_param(reset, bool, 0);
		MODULE_PARM_DESC(reset,
		"Watchdog Interrupt/Reset Mode. 0 = interrupt, 1 = reset");

		static int nowayout = WATCHDOG_NOWAYOUT;
		module_param(nowayout, int, 0);
		MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started "
		"(default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");

		/*
		* We always prescale, but if someone really doesn't want to they can set this
		* to 0
		@@ -70,6 +83,22 @@ static void mpc83xx_wdt_keepalive(void)
		spin_unlock(&wdt_spinlock);
		}

		static void mpc83xx_wdt_timer_ping(unsigned long arg);
		static DEFINE_TIMER(wdt_timer, mpc83xx_wdt_timer_ping, 0, 0);

		static void mpc83xx_wdt_timer_ping(unsigned long arg)
		{
		mpc83xx_wdt_keepalive();
		/* We're pinging it twice faster than needed, just to be sure. */
		mod_timer(&wdt_timer, jiffies + HZ * timeout_sec / 2);
		}

		static void mpc83xx_wdt_pr_warn(const char *msg)
		{
		pr_crit("mpc83xx_wdt: %s, expect the %s soon!\n", msg,
		reset ? "reset" : "machine check exception");
		}

		static ssize_t mpc83xx_wdt_write(struct file file, const char __user buf,
		size_t count, loff_t *ppos)
		{
		@@ -85,6 +114,7 @@ static int mpc83xx_wdt_open(struct inode inode, struct file file)
		return -EBUSY;

		/* Once we start the watchdog we can't stop it */
		if (nowayout)
		__module_get(THIS_MODULE);

		/* Good, fire up the show */
		@@ -97,13 +127,17 @@ static int mpc83xx_wdt_open(struct inode inode, struct file file)

		out_be32(&wd_base->swcrr, tmp);

		del_timer_sync(&wdt_timer);

		return nonseekable_open(inode, file);
		}

		static int mpc83xx_wdt_release(struct inode inode, struct file file)
		{
		printk(KERN_CRIT "Unexpected close, not stopping watchdog!\n");
		mpc83xx_wdt_keepalive();
		if (!nowayout)
		mpc83xx_wdt_timer_ping(0);
		else
		mpc83xx_wdt_pr_warn("watchdog closed");
		clear_bit(0, &wdt_is_open);
		return 0;
		}
		@@ -154,15 +188,25 @@ static int __devinit mpc83xx_wdt_probe(struct of_device *ofdev,
		const struct of_device_id *match)
		{
		int ret;
		struct device_node *np = ofdev->node;
		struct mpc83xx_wdt_type *wdt_type = match->data;
		u32 freq = fsl_get_sys_freq();
		bool enabled;

		if (!freq \|\| freq == -1)
		return -EINVAL;

		wd_base = of_iomap(ofdev->node, 0);
		wd_base = of_iomap(np, 0);
		if (!wd_base)
		return -ENOMEM;

		enabled = in_be32(&wd_base->swcrr) & SWCRR_SWEN;
		if (!enabled && wdt_type->hw_enabled) {
		pr_info("mpc83xx_wdt: could not be enabled in software\n");
		ret = -ENOSYS;
		goto err_unmap;
		}

		ret = misc_register(&mpc83xx_wdt_miscdev);
		if (ret) {
		pr_err("cannot register miscdev on minor=%d (err=%d)\n",
		@@ -172,13 +216,21 @@ static int __devinit mpc83xx_wdt_probe(struct of_device *ofdev,

		/* Calculate the timeout in seconds */
		if (prescale)
		timeout_sec = (timeout * 0x10000) / freq;
		timeout_sec = (timeout * wdt_type->prescaler) / freq;
		else
		timeout_sec = timeout / freq;

		pr_info("WDT driver for MPC83xx initialized. mode:%s timeout=%d "
		"(%d seconds)\n", reset ? "reset" : "interrupt", timeout,
		timeout_sec);

		/*
		* If the watchdog was previously enabled or we're running on
		* MPC86xx, we should ping the wdt from the kernel until the
		* userspace handles it.
		*/
		if (enabled)
		mpc83xx_wdt_timer_ping(0);
		return 0;
		err_unmap:
		iounmap(wd_base);
		@@ -187,6 +239,8 @@ err_unmap:

		static int __devexit mpc83xx_wdt_remove(struct of_device *ofdev)
		{
		mpc83xx_wdt_pr_warn("watchdog removed");
		del_timer_sync(&wdt_timer);
		misc_deregister(&mpc83xx_wdt_miscdev);
		iounmap(wd_base);

		@@ -196,6 +250,16 @@ static int __devexit mpc83xx_wdt_remove(struct of_device *ofdev)
		static const struct of_device_id mpc83xx_wdt_match[] = {
		{
		.compatible = "mpc83xx_wdt",
		.data = &(struct mpc83xx_wdt_type) {
		.prescaler = 0x10000,
		},
		},
		{
		.compatible = "fsl,mpc8610-wdt",
		.data = &(struct mpc83xx_wdt_type) {
		.prescaler = 0x10000,
		.hw_enabled = true,
		},
		},
		{},
		};
		@@ -221,10 +285,10 @@ static void __exit mpc83xx_wdt_exit(void)
		of_unregister_platform_driver(&mpc83xx_wdt_driver);
		}

		module_init(mpc83xx_wdt_init);
		subsys_initcall(mpc83xx_wdt_init);
		module_exit(mpc83xx_wdt_exit);

		MODULE_AUTHOR("Dave Updegraff, Kumar Gala");
		MODULE_DESCRIPTION("Driver for watchdog timer in MPC83xx uProcessor");
		MODULE_DESCRIPTION("Driver for watchdog timer in MPC83xx/MPC86xx uProcessors");
		MODULE_LICENSE("GPL");
		MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);

Admin message