u-boot/drivers/watchdog/ulp_wdog.c
Ye Li 253531bbd9 wdog: Add the watchdog driver for MX7ULP.
This driver implements the HW WATCHDOG functions. Which needs
to set CONFIG_HW_WATCHDOG to use them. This is disabled by default for
mx7ulp.

Use watchdog for reset cpu. Implement this in the driver.
Need to define CONFIG_ULP_WATCHDOG to build it.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Ye Li <ye.li@nxp.com>
Cc: Stefano Babic <sbabic@denx.de>
2017-03-17 09:27:08 +01:00

98 lines
2.1 KiB
C

/*
* Copyright (C) 2016 Freescale Semiconductor, Inc.
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <asm/io.h>
#include <asm/arch/imx-regs.h>
/*
* MX7ULP WDOG Register Map
*/
struct wdog_regs {
u8 cs1;
u8 cs2;
u16 reserve0;
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 WDGCS1_WDGE (1<<7)
#define WDGCS1_WDGUPDATE (1<<5)
#define WDGCS2_FLG (1<<6)
#define WDG_BUS_CLK (0x0)
#define WDG_LPO_CLK (0x1)
#define WDG_32KHZ_CLK (0x2)
#define WDG_EXT_CLK (0x3)
DECLARE_GLOBAL_DATA_PTR;
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;
writel(REFRESH_WORD0, &wdog->cnt);
writel(REFRESH_WORD1, &wdog->cnt);
}
void hw_watchdog_init(void)
{
u8 val;
struct wdog_regs *wdog = (struct wdog_regs *)WDOG_BASE_ADDR;
writel(UNLOCK_WORD0, &wdog->cnt);
writel(UNLOCK_WORD1, &wdog->cnt);
val = readb(&wdog->cs2);
val |= WDGCS2_FLG;
writeb(val, &wdog->cs2);
hw_watchdog_set_timeout(CONFIG_WATCHDOG_TIMEOUT_MSECS);
writel(0, &wdog->win);
writeb(WDG_LPO_CLK, &wdog->cs2);/* setting 1-kHz clock source */
writeb((WDGCS1_WDGE | WDGCS1_WDGUPDATE), &wdog->cs1);/* enable counter running */
hw_watchdog_reset();
}
void reset_cpu(ulong addr)
{
struct wdog_regs *wdog = (struct wdog_regs *)WDOG_BASE_ADDR;
writel(UNLOCK_WORD0, &wdog->cnt);
writel(UNLOCK_WORD1, &wdog->cnt);
hw_watchdog_set_timeout(5); /* 5ms timeout */
writel(0, &wdog->win);
writeb(WDG_LPO_CLK, &wdog->cs2);/* setting 1-kHz clock source */
writeb(WDGCS1_WDGE, &wdog->cs1);/* enable counter running */
hw_watchdog_reset();
while (1);
}