u-boot/drivers/watchdog/npcm_wdt.c
Jim Liu 0ab55cb6f7 wdt: nuvoton: add expire function for generic reset
Add expire_now function for generic sysreset request

Signed-off-by: Jim Liu <JJLIU0@nuvoton.com>
2022-10-24 11:06:24 +02:00

123 lines
2.5 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (c) 2022 Nuvoton Technology, Inc
*/
#include <dm.h>
#include <errno.h>
#include <log.h>
#include <wdt.h>
#include <asm/io.h>
#include <linux/delay.h>
#include <linux/err.h>
#define NPCM_WTCLK (BIT(10) | BIT(11)) /* Clock divider */
#define NPCM_WTE BIT(7) /* Enable */
#define NPCM_WTIE BIT(6) /* Enable irq */
#define NPCM_WTIS (BIT(4) | BIT(5)) /* Interval selection */
#define NPCM_WTIF BIT(3) /* Interrupt flag*/
#define NPCM_WTRF BIT(2) /* Reset flag */
#define NPCM_WTRE BIT(1) /* Reset enable */
#define NPCM_WTR BIT(0) /* Reset counter */
struct npcm_wdt_priv {
void __iomem *regs;
};
static int npcm_wdt_start(struct udevice *dev, u64 timeout_ms, ulong flags)
{
struct npcm_wdt_priv *priv = dev_get_priv(dev);
u32 time_out, val;
time_out = (u32)(timeout_ms) / 1000;
if (time_out < 2)
val = 0x800;
else if (time_out < 3)
val = 0x420;
else if (time_out < 6)
val = 0x810;
else if (time_out < 11)
val = 0x430;
else if (time_out < 22)
val = 0x820;
else if (time_out < 44)
val = 0xc00;
else if (time_out < 87)
val = 0x830;
else if (time_out < 173)
val = 0xc10;
else if (time_out < 688)
val = 0xc20;
else
val = 0xc30;
val |= NPCM_WTRE | NPCM_WTE | NPCM_WTR | NPCM_WTIE;
writel(val, priv->regs);
return 0;
}
static int npcm_wdt_stop(struct udevice *dev)
{
struct npcm_wdt_priv *priv = dev_get_priv(dev);
writel(0, priv->regs);
return 0;
}
static int npcm_wdt_reset(struct udevice *dev)
{
struct npcm_wdt_priv *priv = dev_get_priv(dev);
writel(NPCM_WTR | NPCM_WTRE | NPCM_WTE, priv->regs);
return 0;
}
static int npcm_wdt_expire_now(struct udevice *dev, ulong flags)
{
return npcm_wdt_reset(dev);
}
static int npcm_wdt_of_to_plat(struct udevice *dev)
{
struct npcm_wdt_priv *priv = dev_get_priv(dev);
priv->regs = dev_read_addr_ptr(dev);
if (!priv->regs)
return -EINVAL;
return 0;
}
static const struct wdt_ops npcm_wdt_ops = {
.expire_now = npcm_wdt_expire_now,
.start = npcm_wdt_start,
.reset = npcm_wdt_reset,
.stop = npcm_wdt_stop,
};
static const struct udevice_id npcm_wdt_ids[] = {
{ .compatible = "nuvoton,npcm750-wdt" },
{ }
};
static int npcm_wdt_probe(struct udevice *dev)
{
debug("%s() wdt%u\n", __func__, dev_seq(dev));
npcm_wdt_stop(dev);
return 0;
}
U_BOOT_DRIVER(npcm_wdt) = {
.name = "npcm_wdt",
.id = UCLASS_WDT,
.of_match = npcm_wdt_ids,
.probe = npcm_wdt_probe,
.priv_auto = sizeof(struct npcm_wdt_priv),
.of_to_plat = npcm_wdt_of_to_plat,
.ops = &npcm_wdt_ops,
};