xref: /openbmc/u-boot/drivers/watchdog/s5p_wdt.c (revision dd1033e4)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2012 Samsung Electronics
4  * Minkyu Kang <mk7.kang@samsung.com>
5  */
6 
7 #include <common.h>
8 #include <asm/io.h>
9 #include <asm/arch/watchdog.h>
10 
11 #define PRESCALER_VAL 255
12 
13 void wdt_stop(void)
14 {
15 	struct s5p_watchdog *wdt =
16 		(struct s5p_watchdog *)samsung_get_base_watchdog();
17 	unsigned int wtcon;
18 
19 	wtcon = readl(&wdt->wtcon);
20 	wtcon &= ~(WTCON_EN | WTCON_INT | WTCON_RESET);
21 
22 	writel(wtcon, &wdt->wtcon);
23 }
24 
25 void wdt_start(unsigned int timeout)
26 {
27 	struct s5p_watchdog *wdt =
28 		(struct s5p_watchdog *)samsung_get_base_watchdog();
29 	unsigned int wtcon;
30 
31 	wdt_stop();
32 
33 	wtcon = readl(&wdt->wtcon);
34 	wtcon |= (WTCON_EN | WTCON_CLK(WTCON_CLK_128));
35 	wtcon &= ~WTCON_INT;
36 	wtcon |= WTCON_RESET;
37 	wtcon |= WTCON_PRESCALER(PRESCALER_VAL);
38 
39 	writel(timeout, &wdt->wtdat);
40 	writel(timeout, &wdt->wtcnt);
41 	writel(wtcon, &wdt->wtcon);
42 }
43