1*4882a593Smuzhiyun /*
2*4882a593Smuzhiyun * Copyright (C) 2017 Álvaro Fernández Rojas <noltari@gmail.com>
3*4882a593Smuzhiyun *
4*4882a593Smuzhiyun * Derived from linux/drivers/watchdog/bcm63xx_wdt.c:
5*4882a593Smuzhiyun * Copyright (C) 2007 Miguel Gaio <miguel.gaio@efixo.com>
6*4882a593Smuzhiyun * Copyright (C) 2008 Florian Fainelli <florian@openwrt.org>
7*4882a593Smuzhiyun *
8*4882a593Smuzhiyun * SPDX-License-Identifier: GPL-2.0+
9*4882a593Smuzhiyun */
10*4882a593Smuzhiyun
11*4882a593Smuzhiyun #include <common.h>
12*4882a593Smuzhiyun #include <dm.h>
13*4882a593Smuzhiyun #include <wdt.h>
14*4882a593Smuzhiyun #include <asm/io.h>
15*4882a593Smuzhiyun
16*4882a593Smuzhiyun /* WDT Value register */
17*4882a593Smuzhiyun #define WDT_VAL_REG 0x0
18*4882a593Smuzhiyun #define WDT_VAL_MIN 0x00000002
19*4882a593Smuzhiyun #define WDT_VAL_MAX 0xfffffffe
20*4882a593Smuzhiyun
21*4882a593Smuzhiyun /* WDT Control register */
22*4882a593Smuzhiyun #define WDT_CTL_REG 0x4
23*4882a593Smuzhiyun #define WDT_CTL_START1_MASK 0x0000ff00
24*4882a593Smuzhiyun #define WDT_CTL_START2_MASK 0x000000ff
25*4882a593Smuzhiyun #define WDT_CTL_STOP1_MASK 0x0000ee00
26*4882a593Smuzhiyun #define WDT_CTL_STOP2_MASK 0x000000ee
27*4882a593Smuzhiyun
28*4882a593Smuzhiyun struct bcm6345_wdt_priv {
29*4882a593Smuzhiyun void __iomem *regs;
30*4882a593Smuzhiyun };
31*4882a593Smuzhiyun
bcm6345_wdt_reset(struct udevice * dev)32*4882a593Smuzhiyun static int bcm6345_wdt_reset(struct udevice *dev)
33*4882a593Smuzhiyun {
34*4882a593Smuzhiyun struct bcm6345_wdt_priv *priv = dev_get_priv(dev);
35*4882a593Smuzhiyun
36*4882a593Smuzhiyun writel_be(WDT_CTL_START1_MASK, priv->regs + WDT_CTL_REG);
37*4882a593Smuzhiyun writel_be(WDT_CTL_START2_MASK, priv->regs + WDT_CTL_REG);
38*4882a593Smuzhiyun
39*4882a593Smuzhiyun return 0;
40*4882a593Smuzhiyun }
41*4882a593Smuzhiyun
bcm6345_wdt_start(struct udevice * dev,u64 timeout,ulong flags)42*4882a593Smuzhiyun static int bcm6345_wdt_start(struct udevice *dev, u64 timeout, ulong flags)
43*4882a593Smuzhiyun {
44*4882a593Smuzhiyun struct bcm6345_wdt_priv *priv = dev_get_priv(dev);
45*4882a593Smuzhiyun
46*4882a593Smuzhiyun if (timeout < WDT_VAL_MIN) {
47*4882a593Smuzhiyun debug("watchdog won't fire with less than 2 ticks\n");
48*4882a593Smuzhiyun timeout = WDT_VAL_MIN;
49*4882a593Smuzhiyun } else if (timeout > WDT_VAL_MAX) {
50*4882a593Smuzhiyun debug("maximum watchdog timeout exceeded\n");
51*4882a593Smuzhiyun timeout = WDT_VAL_MAX;
52*4882a593Smuzhiyun }
53*4882a593Smuzhiyun
54*4882a593Smuzhiyun writel_be(timeout, priv->regs + WDT_VAL_REG);
55*4882a593Smuzhiyun
56*4882a593Smuzhiyun return bcm6345_wdt_reset(dev);
57*4882a593Smuzhiyun }
58*4882a593Smuzhiyun
bcm6345_wdt_expire_now(struct udevice * dev,ulong flags)59*4882a593Smuzhiyun static int bcm6345_wdt_expire_now(struct udevice *dev, ulong flags)
60*4882a593Smuzhiyun {
61*4882a593Smuzhiyun return bcm6345_wdt_start(dev, WDT_VAL_MIN, flags);
62*4882a593Smuzhiyun }
63*4882a593Smuzhiyun
bcm6345_wdt_stop(struct udevice * dev)64*4882a593Smuzhiyun static int bcm6345_wdt_stop(struct udevice *dev)
65*4882a593Smuzhiyun {
66*4882a593Smuzhiyun struct bcm6345_wdt_priv *priv = dev_get_priv(dev);
67*4882a593Smuzhiyun
68*4882a593Smuzhiyun writel_be(WDT_CTL_STOP1_MASK, priv->regs + WDT_CTL_REG);
69*4882a593Smuzhiyun writel_be(WDT_CTL_STOP2_MASK, priv->regs + WDT_CTL_REG);
70*4882a593Smuzhiyun
71*4882a593Smuzhiyun return 0;
72*4882a593Smuzhiyun }
73*4882a593Smuzhiyun
74*4882a593Smuzhiyun static const struct wdt_ops bcm6345_wdt_ops = {
75*4882a593Smuzhiyun .expire_now = bcm6345_wdt_expire_now,
76*4882a593Smuzhiyun .reset = bcm6345_wdt_reset,
77*4882a593Smuzhiyun .start = bcm6345_wdt_start,
78*4882a593Smuzhiyun .stop = bcm6345_wdt_stop,
79*4882a593Smuzhiyun };
80*4882a593Smuzhiyun
81*4882a593Smuzhiyun static const struct udevice_id bcm6345_wdt_ids[] = {
82*4882a593Smuzhiyun { .compatible = "brcm,bcm6345-wdt" },
83*4882a593Smuzhiyun { /* sentinel */ }
84*4882a593Smuzhiyun };
85*4882a593Smuzhiyun
bcm6345_wdt_probe(struct udevice * dev)86*4882a593Smuzhiyun static int bcm6345_wdt_probe(struct udevice *dev)
87*4882a593Smuzhiyun {
88*4882a593Smuzhiyun struct bcm6345_wdt_priv *priv = dev_get_priv(dev);
89*4882a593Smuzhiyun fdt_addr_t addr;
90*4882a593Smuzhiyun fdt_size_t size;
91*4882a593Smuzhiyun
92*4882a593Smuzhiyun addr = devfdt_get_addr_size_index(dev, 0, &size);
93*4882a593Smuzhiyun if (addr == FDT_ADDR_T_NONE)
94*4882a593Smuzhiyun return -EINVAL;
95*4882a593Smuzhiyun
96*4882a593Smuzhiyun priv->regs = ioremap(addr, size);
97*4882a593Smuzhiyun
98*4882a593Smuzhiyun bcm6345_wdt_stop(dev);
99*4882a593Smuzhiyun
100*4882a593Smuzhiyun return 0;
101*4882a593Smuzhiyun }
102*4882a593Smuzhiyun
103*4882a593Smuzhiyun U_BOOT_DRIVER(wdt_bcm6345) = {
104*4882a593Smuzhiyun .name = "wdt_bcm6345",
105*4882a593Smuzhiyun .id = UCLASS_WDT,
106*4882a593Smuzhiyun .of_match = bcm6345_wdt_ids,
107*4882a593Smuzhiyun .ops = &bcm6345_wdt_ops,
108*4882a593Smuzhiyun .priv_auto_alloc_size = sizeof(struct bcm6345_wdt_priv),
109*4882a593Smuzhiyun .probe = bcm6345_wdt_probe,
110*4882a593Smuzhiyun };
111