u-boot/drivers/watchdog/mt7621_wdt.c
Stefan Roese 053fce84c1 wdt: Add MT7621 watchdog driver
This patch adds watchdog support for the Mediatek MT7621 SoC. The driver
is loosly based on the Linux kernel version.

Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
[fixed merge conflict in drivers/watchdog/Kconfig]
Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
2018-11-18 16:02:22 +01:00

103 lines
2.1 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Ralink / Mediatek RT288x/RT3xxx/MT76xx built-in hardware watchdog timer
*
* Copyright (C) 2018 Stefan Roese <sr@denx.de>
*
* Based on the Linux driver version which is:
* Copyright (C) 2011 Gabor Juhos <juhosg@openwrt.org>
* Copyright (C) 2013 John Crispin <blogic@openwrt.org>
*/
#include <common.h>
#include <dm.h>
#include <wdt.h>
#include <linux/io.h>
DECLARE_GLOBAL_DATA_PTR;
struct mt762x_wdt {
void __iomem *regs;
};
#define TIMER_REG_TMRSTAT 0x00
#define TIMER_REG_TMR1CTL 0x20
#define TIMER_REG_TMR1LOAD 0x24
#define TMR1CTL_ENABLE BIT(7)
#define TMR1CTL_RESTART BIT(9)
#define TMR1CTL_PRESCALE_SHIFT 16
static int mt762x_wdt_ping(struct mt762x_wdt *priv)
{
writel(TMR1CTL_RESTART, priv->regs + TIMER_REG_TMRSTAT);
return 0;
}
static int mt762x_wdt_start(struct udevice *dev, u64 ms, ulong flags)
{
struct mt762x_wdt *priv = dev_get_priv(dev);
/* set the prescaler to 1ms == 1000us */
writel(1000 << TMR1CTL_PRESCALE_SHIFT, priv->regs + TIMER_REG_TMR1CTL);
writel(ms, priv->regs + TIMER_REG_TMR1LOAD);
setbits_le32(priv->regs + TIMER_REG_TMR1CTL, TMR1CTL_ENABLE);
return 0;
}
static int mt762x_wdt_stop(struct udevice *dev)
{
struct mt762x_wdt *priv = dev_get_priv(dev);
mt762x_wdt_ping(priv);
clrbits_le32(priv->regs + TIMER_REG_TMR1CTL, TMR1CTL_ENABLE);
return 0;
}
static int mt762x_wdt_reset(struct udevice *dev)
{
struct mt762x_wdt *priv = dev_get_priv(dev);
mt762x_wdt_ping(priv);
return 0;
}
static int mt762x_wdt_probe(struct udevice *dev)
{
struct mt762x_wdt *priv = dev_get_priv(dev);
priv->regs = dev_remap_addr(dev);
if (!priv->regs)
return -EINVAL;
mt762x_wdt_stop(dev);
return 0;
}
static const struct wdt_ops mt762x_wdt_ops = {
.start = mt762x_wdt_start,
.reset = mt762x_wdt_reset,
.stop = mt762x_wdt_stop,
};
static const struct udevice_id mt762x_wdt_ids[] = {
{ .compatible = "mediatek,mt7621-wdt" },
{}
};
U_BOOT_DRIVER(mt762x_wdt) = {
.name = "mt762x_wdt",
.id = UCLASS_WDT,
.of_match = mt762x_wdt_ids,
.probe = mt762x_wdt_probe,
.priv_auto_alloc_size = sizeof(struct mt762x_wdt),
.ops = &mt762x_wdt_ops,
};