u-boot/drivers/watchdog/ulp_wdog.c

114 lines
2.5 KiB
C
Raw Normal View History

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2016 Freescale Semiconductor, Inc.
*/
#include <common.h>
#include <cpu_func.h>
#include <asm/io.h>
#include <asm/arch/imx-regs.h>
/*
* MX7ULP WDOG Register Map
*/
struct wdog_regs {
u32 cs;
u32 cnt;
u32 toval;
u32 win;
};
#ifndef CONFIG_WATCHDOG_TIMEOUT_MSECS
#define CONFIG_WATCHDOG_TIMEOUT_MSECS 0x1500
#endif
#define REFRESH_WORD0 0xA602 /* 1st refresh word */
#define REFRESH_WORD1 0xB480 /* 2nd refresh word */
#define UNLOCK_WORD0 0xC520 /* 1st unlock word */
#define UNLOCK_WORD1 0xD928 /* 2nd unlock word */
#define WDGCS_WDGE BIT(7)
#define WDGCS_WDGUPDATE BIT(5)
#define WDGCS_RCS BIT(10)
#define WDGCS_ULK BIT(11)
#define WDGCS_FLG BIT(14)
#define WDG_BUS_CLK (0x0)
#define WDG_LPO_CLK (0x1)
#define WDG_32KHZ_CLK (0x2)
#define WDG_EXT_CLK (0x3)
void hw_watchdog_set_timeout(u16 val)
{
/* setting timeout value */
struct wdog_regs *wdog = (struct wdog_regs *)WDOG_BASE_ADDR;
writel(val, &wdog->toval);
}
void hw_watchdog_reset(void)
{
struct wdog_regs *wdog = (struct wdog_regs *)WDOG_BASE_ADDR;
dmb();
__raw_writel(REFRESH_WORD0, &wdog->cnt);
__raw_writel(REFRESH_WORD1, &wdog->cnt);
dmb();
}
void hw_watchdog_init(void)
{
struct wdog_regs *wdog = (struct wdog_regs *)WDOG_BASE_ADDR;
dmb();
__raw_writel(UNLOCK_WORD0, &wdog->cnt);
__raw_writel(UNLOCK_WORD1, &wdog->cnt);
dmb();
/* Wait WDOG Unlock */
while (!(readl(&wdog->cs) & WDGCS_ULK))
;
hw_watchdog_set_timeout(CONFIG_WATCHDOG_TIMEOUT_MSECS);
writel(0, &wdog->win);
/* setting 1-kHz clock source, enable counter running, and clear interrupt */
writel((WDGCS_WDGE | WDGCS_WDGUPDATE |(WDG_LPO_CLK << 8) | WDGCS_FLG), &wdog->cs);
/* Wait WDOG reconfiguration */
while (!(readl(&wdog->cs) & WDGCS_RCS))
;
hw_watchdog_reset();
}
void reset_cpu(void)
{
struct wdog_regs *wdog = (struct wdog_regs *)WDOG_BASE_ADDR;
dmb();
__raw_writel(UNLOCK_WORD0, &wdog->cnt);
__raw_writel(UNLOCK_WORD1, &wdog->cnt);
dmb();
/* Wait WDOG Unlock */
while (!(readl(&wdog->cs) & WDGCS_ULK))
;
hw_watchdog_set_timeout(5); /* 5ms timeout */
writel(0, &wdog->win);
/* enable counter running */
writel((WDGCS_WDGE | (WDG_LPO_CLK << 8)), &wdog->cs);
/* Wait WDOG reconfiguration */
while (!(readl(&wdog->cs) & WDGCS_RCS))
;
hw_watchdog_reset();
while (1);
}