[J-u-boot.git] / drivers / watchdog / bcm6345_wdt.c

// SPDX-License-Identifier: GPL-2.0+
/*
 * Copyright (C) 2017 Álvaro Fernández Rojas <[email protected]>
 *
 * Derived from linux/drivers/watchdog/bcm63xx_wdt.c:
 *	Copyright (C) 2007 Miguel Gaio <[email protected]>
 *	Copyright (C) 2008 Florian Fainelli <[email protected]>
 */

#include <dm.h>
#include <log.h>
#include <wdt.h>
#include <clk.h>
#include <asm/io.h>

/* WDT Value register */
#define WDT_VAL_REG		0x0
#define WDT_VAL_MIN		0x00000002
#define WDT_VAL_MAX		0xfffffffe

/* WDT Control register */
#define WDT_CTL_REG		0x4
#define WDT_CTL_START1_MASK	0x0000ff00
#define WDT_CTL_START2_MASK	0x000000ff
#define WDT_CTL_STOP1_MASK	0x0000ee00
#define WDT_CTL_STOP2_MASK	0x000000ee

struct bcm6345_wdt_priv {
	void __iomem *regs;
	unsigned long clk_rate;
};

static int bcm6345_wdt_reset(struct udevice *dev)
{
	struct bcm6345_wdt_priv *priv = dev_get_priv(dev);

	writel(WDT_CTL_START1_MASK, priv->regs + WDT_CTL_REG);
	writel(WDT_CTL_START2_MASK, priv->regs + WDT_CTL_REG);

	return 0;
}

static int bcm6345_wdt_start(struct udevice *dev, u64 timeout, ulong flags)
{
	struct bcm6345_wdt_priv *priv = dev_get_priv(dev);
	u32 val = priv->clk_rate / 1000 * timeout;

	if (val < WDT_VAL_MIN) {
		debug("watchdog won't fire with less than 2 ticks\n");
		val = WDT_VAL_MIN;
	} else if (val > WDT_VAL_MAX) {
		debug("maximum watchdog timeout exceeded\n");
		val = WDT_VAL_MAX;
	}

	writel(val, priv->regs + WDT_VAL_REG);

	return bcm6345_wdt_reset(dev);
}

static int bcm6345_wdt_expire_now(struct udevice *dev, ulong flags)
{
	return bcm6345_wdt_start(dev, WDT_VAL_MIN, flags);
}

static int bcm6345_wdt_stop(struct udevice *dev)
{
	struct bcm6345_wdt_priv *priv = dev_get_priv(dev);

	writel(WDT_CTL_STOP1_MASK, priv->regs + WDT_CTL_REG);
	writel(WDT_CTL_STOP2_MASK, priv->regs + WDT_CTL_REG);

	return 0;
}

static const struct wdt_ops bcm6345_wdt_ops = {
	.expire_now = bcm6345_wdt_expire_now,
	.reset = bcm6345_wdt_reset,
	.start = bcm6345_wdt_start,
	.stop = bcm6345_wdt_stop,
};

static const struct udevice_id bcm6345_wdt_ids[] = {
	{ .compatible = "brcm,bcm6345-wdt" },
	{ /* sentinel */ }
};

static int bcm6345_wdt_probe(struct udevice *dev)
{
	struct bcm6345_wdt_priv *priv = dev_get_priv(dev);
	struct clk clk;
	int ret;

	priv->regs = dev_remap_addr(dev);
	if (!priv->regs)
		return -EINVAL;

	ret = clk_get_by_index(dev, 0, &clk);
	if (!ret)
		priv->clk_rate = clk_get_rate(&clk);
	else
		return -EINVAL;

	bcm6345_wdt_stop(dev);

	return 0;
}

U_BOOT_DRIVER(wdt_bcm6345) = {
	.name = "wdt_bcm6345",
	.id = UCLASS_WDT,
	.of_match = bcm6345_wdt_ids,
	.ops = &bcm6345_wdt_ops,
	.priv_auto	= sizeof(struct bcm6345_wdt_priv),
	.probe = bcm6345_wdt_probe,
};
Commit	Line	Data
83d290c5	1	// SPDX-License-Identifier: GPL-2.0+
77331934 ÁFR	2	/*
	3	* Copyright (C) 2017 Álvaro Fernández Rojas <[email protected]>
	4	*
	5	* Derived from linux/drivers/watchdog/bcm63xx_wdt.c:
	6	* Copyright (C) 2007 Miguel Gaio <[email protected]>
	7	* Copyright (C) 2008 Florian Fainelli <[email protected]>
77331934 ÁFR	8	*/
77331934 ÁFR	9
77331934	10	#include <dm.h>
f7ae49fc	11	#include <log.h>
77331934	12	#include <wdt.h>
c411adbd	13	#include <clk.h>
77331934 ÁFR	14	#include <asm/io.h>
	15
	16	/* WDT Value register */
	17	#define WDT_VAL_REG 0x0
	18	#define WDT_VAL_MIN 0x00000002
	19	#define WDT_VAL_MAX 0xfffffffe
	20
	21	/* WDT Control register */
	22	#define WDT_CTL_REG 0x4
	23	#define WDT_CTL_START1_MASK 0x0000ff00
	24	#define WDT_CTL_START2_MASK 0x000000ff
	25	#define WDT_CTL_STOP1_MASK 0x0000ee00
	26	#define WDT_CTL_STOP2_MASK 0x000000ee
	27
	28	struct bcm6345_wdt_priv {
	29	void __iomem *regs;
c411adbd	30	unsigned long clk_rate;
77331934 ÁFR	31	};
	32
	33	static int bcm6345_wdt_reset(struct udevice *dev)
	34	{
	35	struct bcm6345_wdt_priv *priv = dev_get_priv(dev);
	36
771ee9b6 PR	37	writel(WDT_CTL_START1_MASK, priv->regs + WDT_CTL_REG);
771ee9b6 PR	38	writel(WDT_CTL_START2_MASK, priv->regs + WDT_CTL_REG);
77331934 ÁFR	39
	40	return 0;
	41	}
	42
	43	static int bcm6345_wdt_start(struct udevice *dev, u64 timeout, ulong flags)
	44	{
	45	struct bcm6345_wdt_priv *priv = dev_get_priv(dev);
c411adbd	46	u32 val = priv->clk_rate / 1000 * timeout;
77331934	47
c411adbd	48	if (val < WDT_VAL_MIN) {
77331934	49	debug("watchdog won't fire with less than 2 ticks\n");
c411adbd PR	50	val = WDT_VAL_MIN;
c411adbd PR	51	} else if (val > WDT_VAL_MAX) {
77331934	52	debug("maximum watchdog timeout exceeded\n");
c411adbd	53	val = WDT_VAL_MAX;
77331934 ÁFR	54	}
77331934 ÁFR	55
c411adbd	56	writel(val, priv->regs + WDT_VAL_REG);
77331934 ÁFR	57
	58	return bcm6345_wdt_reset(dev);
	59	}
	60
	61	static int bcm6345_wdt_expire_now(struct udevice *dev, ulong flags)
	62	{
	63	return bcm6345_wdt_start(dev, WDT_VAL_MIN, flags);
	64	}
	65
	66	static int bcm6345_wdt_stop(struct udevice *dev)
	67	{
	68	struct bcm6345_wdt_priv *priv = dev_get_priv(dev);
	69
771ee9b6 PR	70	writel(WDT_CTL_STOP1_MASK, priv->regs + WDT_CTL_REG);
771ee9b6 PR	71	writel(WDT_CTL_STOP2_MASK, priv->regs + WDT_CTL_REG);
77331934 ÁFR	72
	73	return 0;
	74	}
	75
	76	static const struct wdt_ops bcm6345_wdt_ops = {
	77	.expire_now = bcm6345_wdt_expire_now,
	78	.reset = bcm6345_wdt_reset,
	79	.start = bcm6345_wdt_start,
	80	.stop = bcm6345_wdt_stop,
	81	};
	82
	83	static const struct udevice_id bcm6345_wdt_ids[] = {
	84	{ .compatible = "brcm,bcm6345-wdt" },
	85	{ /* sentinel */ }
	86	};
	87
	88	static int bcm6345_wdt_probe(struct udevice *dev)
	89	{
	90	struct bcm6345_wdt_priv *priv = dev_get_priv(dev);
c411adbd PR	91	struct clk clk;
c411adbd PR	92	int ret;
77331934	93
aa8f8250 ÁFR	94	priv->regs = dev_remap_addr(dev);
aa8f8250 ÁFR	95	if (!priv->regs)
77331934 ÁFR	96	return -EINVAL;
77331934 ÁFR	97
c411adbd PR	98	ret = clk_get_by_index(dev, 0, &clk);
	99	if (!ret)
	100	priv->clk_rate = clk_get_rate(&clk);
	101	else
	102	return -EINVAL;
	103
77331934 ÁFR	104	bcm6345_wdt_stop(dev);
	105
	106	return 0;
	107	}
	108
	109	U_BOOT_DRIVER(wdt_bcm6345) = {
	110	.name = "wdt_bcm6345",
	111	.id = UCLASS_WDT,
	112	.of_match = bcm6345_wdt_ids,
	113	.ops = &bcm6345_wdt_ops,
41575d8e	114	.priv_auto = sizeof(struct bcm6345_wdt_priv),
77331934 ÁFR	115	.probe = bcm6345_wdt_probe,
77331934 ÁFR	116	};