linuxOS_D21X/source/uboot-2021.10/drivers/watchdog/artinchip_wdt_v1.0.c
2024-11-29 16:13:46 +08:00

150 lines
3.4 KiB
C

// SPDX-License-Identifier: GPL-2.0+ OR BSD-3-Clause
/*
* Copyright (C) 2021 ArtInChip Technology Co.,Ltd.
*/
#define LOG_CATEGORY UCLASS_WDT
#include <common.h>
#include <clk.h>
#include <reset.h>
#include <dm.h>
#include <log.h>
#include <syscon.h>
#include <wdt.h>
#include <asm/io.h>
#include <dm/device_compat.h>
#include <linux/bitops.h>
#include <linux/iopoll.h>
#define WDT_REG_CTRL 0x00
#define WDT_REG_CNTR 0x04
#define WDT_REG_ICR 0x08
#define WDT_REG_ISR 0x0C
/* 4 groups configuration n = [0,1,2,3] */
#define WDT_REG_CLR_CFG(n) (0x40 + n * 0x10)
#define WDT_REG_IRQ_CFG(n) (0x44 + n * 0x10)
#define WDT_REG_RST_CFG(n) (0x48 + n * 0x10)
#define WDT_REG_OP 0xE8
#define CNT_PER_MSECOND (32) /* 32KHz counter clock */
#define WDT_OP_CNT_CLR_CMD0 0xA1C55555
#define WDT_OP_CNT_CLR_CMD1 0xA1CAAAAA
#define WDT_OP_WRITE_EN_CMD0 0xA1C99999
#define WDT_OP_WRITE_EN_CMD1 0xA1C66666
#define WDT_MAX_TIMEOUT_MS (3600000) /* 1 hour */
struct aic_wdt_priv {
fdt_addr_t base; /* registers addr in physical memory */
};
static int aic_wdt_reset(struct udevice *dev)
{
struct aic_wdt_priv *priv = dev_get_priv(dev);
/* Write OP commands in sequence to reset counter and reload cfg */
writel(WDT_OP_CNT_CLR_CMD0, (void *)(priv->base + WDT_REG_OP));
writel(WDT_OP_CNT_CLR_CMD1, (void *)(priv->base + WDT_REG_OP));
return 0;
}
static int aic_wdt_start(struct udevice *dev, u64 timeout_ms, ulong flags)
{
struct aic_wdt_priv *priv = dev_get_priv(dev);
u32 val;
if (timeout_ms > WDT_MAX_TIMEOUT_MS) {
dev_err(dev, "Max timeout is 1hour\n");
return -EINVAL;
}
val = timeout_ms * CNT_PER_MSECOND;
writel(0, (void *)(priv->base + WDT_REG_CLR_CFG(0)));
writel(val, (void *)(priv->base + WDT_REG_IRQ_CFG(0)));
writel(val, (void *)(priv->base + WDT_REG_RST_CFG(0)));
/* Reset counter and reload cfg */
aic_wdt_reset(dev);
/* Enable watchdog */
writel(1, (void *)(priv->base + WDT_REG_CTRL));
return 0;
}
static int aic_wdt_expire_now(struct udevice *dev, ulong flags)
{
return aic_wdt_start(dev, 0, flags);
}
static int aic_wdt_stop(struct udevice *dev)
{
struct aic_wdt_priv *priv = dev_get_priv(dev);
writel(0, (void *)(priv->base + WDT_REG_CTRL));
return 0;
}
static int aic_wdt_probe(struct udevice *dev)
{
struct aic_wdt_priv *priv = dev_get_priv(dev);
struct clk clk;
struct reset_ctl reset;
int ret;
priv->base = dev_read_addr(dev);
if (priv->base == FDT_ADDR_T_NONE)
return -EINVAL;
ret = clk_get_by_index(dev, 0, &clk);
if (ret && ret != -ENOENT) {
dev_err(dev, "failed to get clock\n");
return ret;
}
ret = clk_enable(&clk);
if (ret)
return ret;
ret = reset_get_by_index(dev, 0, &reset);
if (ret && ret != -ENOENT) {
dev_err(dev, "failed to get reset\n");
return ret;
}
ret = reset_deassert(&reset);
if (ret) {
dev_err(dev, "failed to deassert reset\n");
return ret;
}
dev_info(dev, "%s done\n", __func__);
return 0;
}
static const struct wdt_ops aic_wdt_ops = {
.start = aic_wdt_start,
.stop = aic_wdt_stop,
.expire_now = aic_wdt_expire_now,
.reset = aic_wdt_reset,
};
static const struct udevice_id aic_wdt_match[] = {
{ .compatible = "artinchip,aic-wdt-v1.0" },
{ /* sentinel */ }
};
U_BOOT_DRIVER(aic_wdt) = {
.name = "artinchip_aic_wdt_v1_0",
.id = UCLASS_WDT,
.of_match = aic_wdt_match,
.priv_auto = sizeof(struct aic_wdt_priv),
.probe = aic_wdt_probe,
.ops = &aic_wdt_ops,
};