[linux-2.6-block.git] / drivers / watchdog / bcm_kona_wdt.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (C) 2013 Broadcom Corporation
 *
 */

#include <linux/debugfs.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/of_address.h>
#include <linux/platform_device.h>
#include <linux/watchdog.h>

#define SECWDOG_CTRL_REG		0x00000000
#define SECWDOG_COUNT_REG		0x00000004

#define SECWDOG_RESERVED_MASK		0x1dffffff
#define SECWDOG_WD_LOAD_FLAG		0x10000000
#define SECWDOG_EN_MASK			0x08000000
#define SECWDOG_SRSTEN_MASK		0x04000000
#define SECWDOG_RES_MASK		0x00f00000
#define SECWDOG_COUNT_MASK		0x000fffff

#define SECWDOG_MAX_COUNT		SECWDOG_COUNT_MASK
#define SECWDOG_CLKS_SHIFT		20
#define SECWDOG_MAX_RES			15
#define SECWDOG_DEFAULT_RESOLUTION	4
#define SECWDOG_MAX_TRY			1000

#define SECS_TO_TICKS(x, w)		((x) << (w)->resolution)
#define TICKS_TO_SECS(x, w)		((x) >> (w)->resolution)

#define BCM_KONA_WDT_NAME		"bcm_kona_wdt"

struct bcm_kona_wdt {
	void __iomem *base;
	/*
	 * One watchdog tick is 1/(2^resolution) seconds. Resolution can take
	 * the values 0-15, meaning one tick can be 1s to 30.52us. Our default
	 * resolution of 4 means one tick is 62.5ms.
	 *
	 * The watchdog counter is 20 bits. Depending on resolution, the maximum
	 * counter value of 0xfffff expires after about 12 days (resolution 0)
	 * down to only 32s (resolution 15). The default resolution of 4 gives
	 * us a maximum of about 18 hours and 12 minutes before the watchdog
	 * times out.
	 */
	int resolution;
	spinlock_t lock;
#ifdef CONFIG_BCM_KONA_WDT_DEBUG
	unsigned long busy_count;
	struct dentry *debugfs;
#endif
};

static int secure_register_read(struct bcm_kona_wdt *wdt, uint32_t offset)
{
	uint32_t val;
	unsigned count = 0;

	/*
	 * If the WD_LOAD_FLAG is set, the watchdog counter field is being
	 * updated in hardware. Once the WD timer is updated in hardware, it
	 * gets cleared.
	 */
	do {
		if (unlikely(count > 1))
			udelay(5);
		val = readl_relaxed(wdt->base + offset);
		count++;
	} while ((val & SECWDOG_WD_LOAD_FLAG) && count < SECWDOG_MAX_TRY);

#ifdef CONFIG_BCM_KONA_WDT_DEBUG
	/* Remember the maximum number iterations due to WD_LOAD_FLAG */
	if (count > wdt->busy_count)
		wdt->busy_count = count;
#endif

	/* This is the only place we return a negative value. */
	if (val & SECWDOG_WD_LOAD_FLAG)
		return -ETIMEDOUT;

	/* We always mask out reserved bits. */
	val &= SECWDOG_RESERVED_MASK;

	return val;
}

#ifdef CONFIG_BCM_KONA_WDT_DEBUG

static int bcm_kona_show(struct seq_file *s, void *data)
{
	int ctl_val, cur_val;
	unsigned long flags;
	struct bcm_kona_wdt *wdt = s->private;

	if (!wdt) {
		seq_puts(s, "No device pointer\n");
		return 0;
	}

	spin_lock_irqsave(&wdt->lock, flags);
	ctl_val = secure_register_read(wdt, SECWDOG_CTRL_REG);
	cur_val = secure_register_read(wdt, SECWDOG_COUNT_REG);
	spin_unlock_irqrestore(&wdt->lock, flags);

	if (ctl_val < 0 || cur_val < 0) {
		seq_puts(s, "Error accessing hardware\n");
	} else {
		int ctl, cur, ctl_sec, cur_sec, res;

		ctl = ctl_val & SECWDOG_COUNT_MASK;
		res = (ctl_val & SECWDOG_RES_MASK) >> SECWDOG_CLKS_SHIFT;
		cur = cur_val & SECWDOG_COUNT_MASK;
		ctl_sec = TICKS_TO_SECS(ctl, wdt);
		cur_sec = TICKS_TO_SECS(cur, wdt);
		seq_printf(s,
			   "Resolution: %d / %d\n"
			   "Control: %d s / %d (%#x) ticks\n"
			   "Current: %d s / %d (%#x) ticks\n"
			   "Busy count: %lu\n",
			   res, wdt->resolution,
			   ctl_sec, ctl, ctl,
			   cur_sec, cur, cur,
			   wdt->busy_count);
	}

	return 0;
}

DEFINE_SHOW_ATTRIBUTE(bcm_kona);

static void bcm_kona_wdt_debug_init(struct platform_device *pdev)
{
	struct dentry *dir;
	struct bcm_kona_wdt *wdt = platform_get_drvdata(pdev);

	if (!wdt)
		return;

	wdt->debugfs = NULL;

	dir = debugfs_create_dir(BCM_KONA_WDT_NAME, NULL);
	if (IS_ERR_OR_NULL(dir))
		return;

	if (debugfs_create_file("info", S_IFREG | S_IRUGO, dir, wdt,
				&bcm_kona_fops))
		wdt->debugfs = dir;
	else
		debugfs_remove_recursive(dir);
}

static void bcm_kona_wdt_debug_exit(struct platform_device *pdev)
{
	struct bcm_kona_wdt *wdt = platform_get_drvdata(pdev);

	if (wdt && wdt->debugfs) {
		debugfs_remove_recursive(wdt->debugfs);
		wdt->debugfs = NULL;
	}
}

#else

static void bcm_kona_wdt_debug_init(struct platform_device *pdev) {}
static void bcm_kona_wdt_debug_exit(struct platform_device *pdev) {}

#endif /* CONFIG_BCM_KONA_WDT_DEBUG */

static int bcm_kona_wdt_ctrl_reg_modify(struct bcm_kona_wdt *wdt,
					unsigned mask, unsigned newval)
{
	int val;
	unsigned long flags;
	int ret = 0;

	spin_lock_irqsave(&wdt->lock, flags);

	val = secure_register_read(wdt, SECWDOG_CTRL_REG);
	if (val < 0) {
		ret = val;
	} else {
		val &= ~mask;
		val |= newval;
		writel_relaxed(val, wdt->base + SECWDOG_CTRL_REG);
	}

	spin_unlock_irqrestore(&wdt->lock, flags);

	return ret;
}

static int bcm_kona_wdt_set_resolution_reg(struct bcm_kona_wdt *wdt)
{
	if (wdt->resolution > SECWDOG_MAX_RES)
		return -EINVAL;

	return bcm_kona_wdt_ctrl_reg_modify(wdt, SECWDOG_RES_MASK,
					wdt->resolution << SECWDOG_CLKS_SHIFT);
}

static int bcm_kona_wdt_set_timeout_reg(struct watchdog_device *wdog,
					unsigned watchdog_flags)
{
	struct bcm_kona_wdt *wdt = watchdog_get_drvdata(wdog);

	return bcm_kona_wdt_ctrl_reg_modify(wdt, SECWDOG_COUNT_MASK,
					SECS_TO_TICKS(wdog->timeout, wdt) |
					watchdog_flags);
}

static int bcm_kona_wdt_set_timeout(struct watchdog_device *wdog,
	unsigned int t)
{
	wdog->timeout = t;
	return 0;
}

static unsigned int bcm_kona_wdt_get_timeleft(struct watchdog_device *wdog)
{
	struct bcm_kona_wdt *wdt = watchdog_get_drvdata(wdog);
	int val;
	unsigned long flags;

	spin_lock_irqsave(&wdt->lock, flags);
	val = secure_register_read(wdt, SECWDOG_COUNT_REG);
	spin_unlock_irqrestore(&wdt->lock, flags);

	if (val < 0)
		return val;

	return TICKS_TO_SECS(val & SECWDOG_COUNT_MASK, wdt);
}

static int bcm_kona_wdt_start(struct watchdog_device *wdog)
{
	return bcm_kona_wdt_set_timeout_reg(wdog,
					SECWDOG_EN_MASK | SECWDOG_SRSTEN_MASK);
}

static int bcm_kona_wdt_stop(struct watchdog_device *wdog)
{
	struct bcm_kona_wdt *wdt = watchdog_get_drvdata(wdog);

	return bcm_kona_wdt_ctrl_reg_modify(wdt, SECWDOG_EN_MASK |
					    SECWDOG_SRSTEN_MASK, 0);
}

static const struct watchdog_ops bcm_kona_wdt_ops = {
	.owner =	THIS_MODULE,
	.start =	bcm_kona_wdt_start,
	.stop =		bcm_kona_wdt_stop,
	.set_timeout =	bcm_kona_wdt_set_timeout,
	.get_timeleft =	bcm_kona_wdt_get_timeleft,
};

static const struct watchdog_info bcm_kona_wdt_info = {
	.options =	WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE |
			WDIOF_KEEPALIVEPING,
	.identity =	"Broadcom Kona Watchdog Timer",
};

static struct watchdog_device bcm_kona_wdt_wdd = {
	.info =		&bcm_kona_wdt_info,
	.ops =		&bcm_kona_wdt_ops,
	.min_timeout =	1,
	.max_timeout =	SECWDOG_MAX_COUNT >> SECWDOG_DEFAULT_RESOLUTION,
	.timeout =	SECWDOG_MAX_COUNT >> SECWDOG_DEFAULT_RESOLUTION,
};

static void bcm_kona_wdt_shutdown(struct platform_device *pdev)
{
	bcm_kona_wdt_stop(&bcm_kona_wdt_wdd);
}

static int bcm_kona_wdt_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct bcm_kona_wdt *wdt;
	struct resource *res;
	int ret;

	wdt = devm_kzalloc(dev, sizeof(*wdt), GFP_KERNEL);
	if (!wdt)
		return -ENOMEM;

	spin_lock_init(&wdt->lock);

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	wdt->base = devm_ioremap_resource(dev, res);
	if (IS_ERR(wdt->base))
		return -ENODEV;

	wdt->resolution = SECWDOG_DEFAULT_RESOLUTION;
	ret = bcm_kona_wdt_set_resolution_reg(wdt);
	if (ret) {
		dev_err(dev, "Failed to set resolution (error: %d)", ret);
		return ret;
	}

	platform_set_drvdata(pdev, wdt);
	watchdog_set_drvdata(&bcm_kona_wdt_wdd, wdt);
	bcm_kona_wdt_wdd.parent = &pdev->dev;

	ret = bcm_kona_wdt_set_timeout_reg(&bcm_kona_wdt_wdd, 0);
	if (ret) {
		dev_err(dev, "Failed set watchdog timeout");
		return ret;
	}

	ret = watchdog_register_device(&bcm_kona_wdt_wdd);
	if (ret) {
		dev_err(dev, "Failed to register watchdog device");
		return ret;
	}

	bcm_kona_wdt_debug_init(pdev);
	dev_dbg(dev, "Broadcom Kona Watchdog Timer");

	return 0;
}

static int bcm_kona_wdt_remove(struct platform_device *pdev)
{
	bcm_kona_wdt_debug_exit(pdev);
	bcm_kona_wdt_shutdown(pdev);
	watchdog_unregister_device(&bcm_kona_wdt_wdd);
	dev_dbg(&pdev->dev, "Watchdog driver disabled");

	return 0;
}

static const struct of_device_id bcm_kona_wdt_of_match[] = {
	{ .compatible = "brcm,kona-wdt", },
	{},
};
MODULE_DEVICE_TABLE(of, bcm_kona_wdt_of_match);

static struct platform_driver bcm_kona_wdt_driver = {
	.driver = {
			.name = BCM_KONA_WDT_NAME,
			.of_match_table = bcm_kona_wdt_of_match,
		  },
	.probe = bcm_kona_wdt_probe,
	.remove = bcm_kona_wdt_remove,
	.shutdown = bcm_kona_wdt_shutdown,
};

module_platform_driver(bcm_kona_wdt_driver);

MODULE_ALIAS("platform:" BCM_KONA_WDT_NAME);
MODULE_AUTHOR("Markus Mayer <mmayer@broadcom.com>");
MODULE_DESCRIPTION("Broadcom Kona Watchdog Driver");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
2e62c498	1	// SPDX-License-Identifier: GPL-2.0
6adb730d MM	2	/*
	3	* Copyright (C) 2013 Broadcom Corporation
	4	*
6adb730d MM	5	*/
6adb730d MM	6
6e2ac20e	7	#include <linux/debugfs.h>
6adb730d MM	8	#include <linux/delay.h>
	9	#include <linux/err.h>
	10	#include <linux/io.h>
	11	#include <linux/module.h>
	12	#include <linux/of_address.h>
	13	#include <linux/platform_device.h>
	14	#include <linux/watchdog.h>
	15
	16	#define SECWDOG_CTRL_REG 0x00000000
	17	#define SECWDOG_COUNT_REG 0x00000004
	18
	19	#define SECWDOG_RESERVED_MASK 0x1dffffff
	20	#define SECWDOG_WD_LOAD_FLAG 0x10000000
	21	#define SECWDOG_EN_MASK 0x08000000
	22	#define SECWDOG_SRSTEN_MASK 0x04000000
	23	#define SECWDOG_RES_MASK 0x00f00000
	24	#define SECWDOG_COUNT_MASK 0x000fffff
	25
	26	#define SECWDOG_MAX_COUNT SECWDOG_COUNT_MASK
	27	#define SECWDOG_CLKS_SHIFT 20
	28	#define SECWDOG_MAX_RES 15
	29	#define SECWDOG_DEFAULT_RESOLUTION 4
	30	#define SECWDOG_MAX_TRY 1000
	31
	32	#define SECS_TO_TICKS(x, w) ((x) << (w)->resolution)
	33	#define TICKS_TO_SECS(x, w) ((x) >> (w)->resolution)
	34
	35	#define BCM_KONA_WDT_NAME "bcm_kona_wdt"
	36
	37	struct bcm_kona_wdt {
	38	void __iomem *base;
	39	/*
	40	* One watchdog tick is 1/(2^resolution) seconds. Resolution can take
	41	* the values 0-15, meaning one tick can be 1s to 30.52us. Our default
	42	* resolution of 4 means one tick is 62.5ms.
	43	*
	44	* The watchdog counter is 20 bits. Depending on resolution, the maximum
	45	* counter value of 0xfffff expires after about 12 days (resolution 0)
	46	* down to only 32s (resolution 15). The default resolution of 4 gives
	47	* us a maximum of about 18 hours and 12 minutes before the watchdog
	48	* times out.
	49	*/
	50	int resolution;
	51	spinlock_t lock;
6e2ac20e MM	52	#ifdef CONFIG_BCM_KONA_WDT_DEBUG
	53	unsigned long busy_count;
	54	struct dentry *debugfs;
	55	#endif
6adb730d MM	56	};
6adb730d MM	57
6e2ac20e	58	static int secure_register_read(struct bcm_kona_wdt *wdt, uint32_t offset)
6adb730d MM	59	{
	60	uint32_t val;
	61	unsigned count = 0;
	62
	63	/*
	64	* If the WD_LOAD_FLAG is set, the watchdog counter field is being
	65	* updated in hardware. Once the WD timer is updated in hardware, it
	66	* gets cleared.
	67	*/
	68	do {
	69	if (unlikely(count > 1))
	70	udelay(5);
6e2ac20e	71	val = readl_relaxed(wdt->base + offset);
6adb730d MM	72	count++;
	73	} while ((val & SECWDOG_WD_LOAD_FLAG) && count < SECWDOG_MAX_TRY);
	74
6e2ac20e MM	75	#ifdef CONFIG_BCM_KONA_WDT_DEBUG
	76	/* Remember the maximum number iterations due to WD_LOAD_FLAG */
	77	if (count > wdt->busy_count)
	78	wdt->busy_count = count;
	79	#endif
	80
6adb730d MM	81	/* This is the only place we return a negative value. */
	82	if (val & SECWDOG_WD_LOAD_FLAG)
	83	return -ETIMEDOUT;
	84
	85	/* We always mask out reserved bits. */
	86	val &= SECWDOG_RESERVED_MASK;
	87
	88	return val;
	89	}
	90
6e2ac20e MM	91	#ifdef CONFIG_BCM_KONA_WDT_DEBUG
6e2ac20e MM	92
57808f44	93	static int bcm_kona_show(struct seq_file s, void data)
6e2ac20e	94	{
e1dbde29	95	int ctl_val, cur_val;
6e2ac20e MM	96	unsigned long flags;
	97	struct bcm_kona_wdt *wdt = s->private;
	98
e1dbde29 JP	99	if (!wdt) {
	100	seq_puts(s, "No device pointer\n");
	101	return 0;
	102	}
6e2ac20e MM	103
	104	spin_lock_irqsave(&wdt->lock, flags);
	105	ctl_val = secure_register_read(wdt, SECWDOG_CTRL_REG);
	106	cur_val = secure_register_read(wdt, SECWDOG_COUNT_REG);
	107	spin_unlock_irqrestore(&wdt->lock, flags);
	108
	109	if (ctl_val < 0 \|\| cur_val < 0) {
e1dbde29	110	seq_puts(s, "Error accessing hardware\n");
6e2ac20e MM	111	} else {
	112	int ctl, cur, ctl_sec, cur_sec, res;
	113
	114	ctl = ctl_val & SECWDOG_COUNT_MASK;
	115	res = (ctl_val & SECWDOG_RES_MASK) >> SECWDOG_CLKS_SHIFT;
	116	cur = cur_val & SECWDOG_COUNT_MASK;
	117	ctl_sec = TICKS_TO_SECS(ctl, wdt);
	118	cur_sec = TICKS_TO_SECS(cur, wdt);
e1dbde29 JP	119	seq_printf(s,
	120	"Resolution: %d / %d\n"
	121	"Control: %d s / %d (%#x) ticks\n"
	122	"Current: %d s / %d (%#x) ticks\n"
	123	"Busy count: %lu\n",
	124	res, wdt->resolution,
	125	ctl_sec, ctl, ctl,
	126	cur_sec, cur, cur,
	127	wdt->busy_count);
6e2ac20e MM	128	}
6e2ac20e MM	129
e1dbde29	130	return 0;
6e2ac20e MM	131	}
6e2ac20e MM	132
57808f44	133	DEFINE_SHOW_ATTRIBUTE(bcm_kona);
6e2ac20e MM	134
	135	static void bcm_kona_wdt_debug_init(struct platform_device *pdev)
	136	{
	137	struct dentry *dir;
	138	struct bcm_kona_wdt *wdt = platform_get_drvdata(pdev);
	139
	140	if (!wdt)
	141	return;
	142
	143	wdt->debugfs = NULL;
	144
	145	dir = debugfs_create_dir(BCM_KONA_WDT_NAME, NULL);
	146	if (IS_ERR_OR_NULL(dir))
	147	return;
	148
	149	if (debugfs_create_file("info", S_IFREG \| S_IRUGO, dir, wdt,
57808f44	150	&bcm_kona_fops))
6e2ac20e MM	151	wdt->debugfs = dir;
	152	else
	153	debugfs_remove_recursive(dir);
	154	}
	155
	156	static void bcm_kona_wdt_debug_exit(struct platform_device *pdev)
	157	{
	158	struct bcm_kona_wdt *wdt = platform_get_drvdata(pdev);
	159
	160	if (wdt && wdt->debugfs) {
	161	debugfs_remove_recursive(wdt->debugfs);
	162	wdt->debugfs = NULL;
	163	}
	164	}
	165
	166	#else
	167
	168	static void bcm_kona_wdt_debug_init(struct platform_device *pdev) {}
	169	static void bcm_kona_wdt_debug_exit(struct platform_device *pdev) {}
	170
	171	#endif /* CONFIG_BCM_KONA_WDT_DEBUG */
	172
6adb730d MM	173	static int bcm_kona_wdt_ctrl_reg_modify(struct bcm_kona_wdt *wdt,
	174	unsigned mask, unsigned newval)
	175	{
	176	int val;
	177	unsigned long flags;
	178	int ret = 0;
	179
	180	spin_lock_irqsave(&wdt->lock, flags);
	181
6e2ac20e	182	val = secure_register_read(wdt, SECWDOG_CTRL_REG);
6adb730d MM	183	if (val < 0) {
	184	ret = val;
	185	} else {
	186	val &= ~mask;
	187	val \|= newval;
	188	writel_relaxed(val, wdt->base + SECWDOG_CTRL_REG);
	189	}
	190
	191	spin_unlock_irqrestore(&wdt->lock, flags);
	192
	193	return ret;
	194	}
	195
	196	static int bcm_kona_wdt_set_resolution_reg(struct bcm_kona_wdt *wdt)
	197	{
	198	if (wdt->resolution > SECWDOG_MAX_RES)
	199	return -EINVAL;
	200
	201	return bcm_kona_wdt_ctrl_reg_modify(wdt, SECWDOG_RES_MASK,
	202	wdt->resolution << SECWDOG_CLKS_SHIFT);
	203	}
	204
	205	static int bcm_kona_wdt_set_timeout_reg(struct watchdog_device *wdog,
	206	unsigned watchdog_flags)
	207	{
	208	struct bcm_kona_wdt *wdt = watchdog_get_drvdata(wdog);
	209
	210	return bcm_kona_wdt_ctrl_reg_modify(wdt, SECWDOG_COUNT_MASK,
	211	SECS_TO_TICKS(wdog->timeout, wdt) \|
	212	watchdog_flags);
	213	}
	214
	215	static int bcm_kona_wdt_set_timeout(struct watchdog_device *wdog,
	216	unsigned int t)
	217	{
	218	wdog->timeout = t;
	219	return 0;
	220	}
	221
	222	static unsigned int bcm_kona_wdt_get_timeleft(struct watchdog_device *wdog)
	223	{
	224	struct bcm_kona_wdt *wdt = watchdog_get_drvdata(wdog);
	225	int val;
	226	unsigned long flags;
	227
	228	spin_lock_irqsave(&wdt->lock, flags);
6e2ac20e	229	val = secure_register_read(wdt, SECWDOG_COUNT_REG);
6adb730d MM	230	spin_unlock_irqrestore(&wdt->lock, flags);
	231
	232	if (val < 0)
	233	return val;
	234
	235	return TICKS_TO_SECS(val & SECWDOG_COUNT_MASK, wdt);
	236	}
	237
	238	static int bcm_kona_wdt_start(struct watchdog_device *wdog)
	239	{
	240	return bcm_kona_wdt_set_timeout_reg(wdog,
	241	SECWDOG_EN_MASK \| SECWDOG_SRSTEN_MASK);
	242	}
	243
	244	static int bcm_kona_wdt_stop(struct watchdog_device *wdog)
	245	{
	246	struct bcm_kona_wdt *wdt = watchdog_get_drvdata(wdog);
	247
	248	return bcm_kona_wdt_ctrl_reg_modify(wdt, SECWDOG_EN_MASK \|
	249	SECWDOG_SRSTEN_MASK, 0);
	250	}
	251
b893e344	252	static const struct watchdog_ops bcm_kona_wdt_ops = {
6adb730d MM	253	.owner = THIS_MODULE,
	254	.start = bcm_kona_wdt_start,
	255	.stop = bcm_kona_wdt_stop,
	256	.set_timeout = bcm_kona_wdt_set_timeout,
	257	.get_timeleft = bcm_kona_wdt_get_timeleft,
	258	};
	259
6c368932	260	static const struct watchdog_info bcm_kona_wdt_info = {
6adb730d MM	261	.options = WDIOF_SETTIMEOUT \| WDIOF_MAGICCLOSE \|
	262	WDIOF_KEEPALIVEPING,
	263	.identity = "Broadcom Kona Watchdog Timer",
	264	};
	265
	266	static struct watchdog_device bcm_kona_wdt_wdd = {
	267	.info = &bcm_kona_wdt_info,
	268	.ops = &bcm_kona_wdt_ops,
	269	.min_timeout = 1,
	270	.max_timeout = SECWDOG_MAX_COUNT >> SECWDOG_DEFAULT_RESOLUTION,
	271	.timeout = SECWDOG_MAX_COUNT >> SECWDOG_DEFAULT_RESOLUTION,
	272	};
	273
	274	static void bcm_kona_wdt_shutdown(struct platform_device *pdev)
	275	{
	276	bcm_kona_wdt_stop(&bcm_kona_wdt_wdd);
	277	}
	278
	279	static int bcm_kona_wdt_probe(struct platform_device *pdev)
	280	{
	281	struct device *dev = &pdev->dev;
	282	struct bcm_kona_wdt *wdt;
	283	struct resource *res;
	284	int ret;
	285
	286	wdt = devm_kzalloc(dev, sizeof(*wdt), GFP_KERNEL);
	287	if (!wdt)
	288	return -ENOMEM;
	289
fedf266f EA	290	spin_lock_init(&wdt->lock);
fedf266f EA	291
6adb730d MM	292	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	293	wdt->base = devm_ioremap_resource(dev, res);
	294	if (IS_ERR(wdt->base))
	295	return -ENODEV;
	296
	297	wdt->resolution = SECWDOG_DEFAULT_RESOLUTION;
	298	ret = bcm_kona_wdt_set_resolution_reg(wdt);
	299	if (ret) {
	300	dev_err(dev, "Failed to set resolution (error: %d)", ret);
	301	return ret;
	302	}
	303
6adb730d MM	304	platform_set_drvdata(pdev, wdt);
6adb730d MM	305	watchdog_set_drvdata(&bcm_kona_wdt_wdd, wdt);
6551881c	306	bcm_kona_wdt_wdd.parent = &pdev->dev;
6adb730d MM	307
	308	ret = bcm_kona_wdt_set_timeout_reg(&bcm_kona_wdt_wdd, 0);
	309	if (ret) {
	310	dev_err(dev, "Failed set watchdog timeout");
	311	return ret;
	312	}
	313
	314	ret = watchdog_register_device(&bcm_kona_wdt_wdd);
	315	if (ret) {
	316	dev_err(dev, "Failed to register watchdog device");
	317	return ret;
	318	}
	319
6e2ac20e	320	bcm_kona_wdt_debug_init(pdev);
6adb730d MM	321	dev_dbg(dev, "Broadcom Kona Watchdog Timer");
	322
	323	return 0;
	324	}
	325
	326	static int bcm_kona_wdt_remove(struct platform_device *pdev)
	327	{
6e2ac20e	328	bcm_kona_wdt_debug_exit(pdev);
6adb730d MM	329	bcm_kona_wdt_shutdown(pdev);
	330	watchdog_unregister_device(&bcm_kona_wdt_wdd);
	331	dev_dbg(&pdev->dev, "Watchdog driver disabled");
	332
	333	return 0;
	334	}
	335
	336	static const struct of_device_id bcm_kona_wdt_of_match[] = {
	337	{ .compatible = "brcm,kona-wdt", },
	338	{},
	339	};
	340	MODULE_DEVICE_TABLE(of, bcm_kona_wdt_of_match);
	341
	342	static struct platform_driver bcm_kona_wdt_driver = {
	343	.driver = {
	344	.name = BCM_KONA_WDT_NAME,
6adb730d MM	345	.of_match_table = bcm_kona_wdt_of_match,
	346	},
	347	.probe = bcm_kona_wdt_probe,
	348	.remove = bcm_kona_wdt_remove,
	349	.shutdown = bcm_kona_wdt_shutdown,
	350	};
	351
	352	module_platform_driver(bcm_kona_wdt_driver);
	353
	354	MODULE_ALIAS("platform:" BCM_KONA_WDT_NAME);
	355	MODULE_AUTHOR("Markus Mayer <mmayer@broadcom.com>");
	356	MODULE_DESCRIPTION("Broadcom Kona Watchdog Driver");
	357	MODULE_LICENSE("GPL v2");