1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
|
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (c) 2016 Yang Ling <gnaygnil@gmail.com>
* Copyright (C) 2025 Binbin Zhou <zhoubinbin@loongson.cn>
*/
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/watchdog.h>
/* Loongson Watchdog Register Definitions */
#define WDT_EN 0x0
#define DEFAULT_HEARTBEAT 30
static bool nowayout = WATCHDOG_NOWAYOUT;
module_param(nowayout, bool, 0);
MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
static unsigned int heartbeat;
module_param(heartbeat, uint, 0);
MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds. (default="
__MODULE_STRING(DEFAULT_HEARTBEAT) ")");
struct ls1x_wdt_pdata {
u32 timer_offset;
u32 set_offset;
u32 wdt_en_bit;
};
static const struct ls1x_wdt_pdata ls1b_wdt_pdata = {
.timer_offset = 0x4,
.set_offset = 0x8,
.wdt_en_bit = BIT(0),
};
static const struct ls1x_wdt_pdata ls2k0300_wdt_pdata = {
.timer_offset = 0x8,
.set_offset = 0x4,
.wdt_en_bit = BIT(1),
};
struct ls1x_wdt_drvdata {
void __iomem *base;
struct clk *clk;
unsigned long clk_rate;
struct watchdog_device wdt;
const struct ls1x_wdt_pdata *pdata;
};
static int ls1x_wdt_ping(struct watchdog_device *wdt_dev)
{
struct ls1x_wdt_drvdata *drvdata = watchdog_get_drvdata(wdt_dev);
writel(0x1, drvdata->base + drvdata->pdata->set_offset);
return 0;
}
static int ls1x_wdt_set_timeout(struct watchdog_device *wdt_dev,
unsigned int timeout)
{
struct ls1x_wdt_drvdata *drvdata = watchdog_get_drvdata(wdt_dev);
unsigned int max_hw_heartbeat = wdt_dev->max_hw_heartbeat_ms / 1000;
unsigned int counts;
wdt_dev->timeout = timeout;
counts = drvdata->clk_rate * min(timeout, max_hw_heartbeat);
writel(counts, drvdata->base + drvdata->pdata->timer_offset);
return 0;
}
static int ls1x_wdt_start(struct watchdog_device *wdt_dev)
{
struct ls1x_wdt_drvdata *drvdata = watchdog_get_drvdata(wdt_dev);
writel(drvdata->pdata->wdt_en_bit, drvdata->base + WDT_EN);
return 0;
}
static int ls1x_wdt_stop(struct watchdog_device *wdt_dev)
{
struct ls1x_wdt_drvdata *drvdata = watchdog_get_drvdata(wdt_dev);
u32 val = readl(drvdata->base + WDT_EN);
val &= ~(drvdata->pdata->wdt_en_bit);
writel(val, drvdata->base + WDT_EN);
return 0;
}
static int ls1x_wdt_restart(struct watchdog_device *wdt_dev,
unsigned long action, void *data)
{
struct ls1x_wdt_drvdata *drvdata = watchdog_get_drvdata(wdt_dev);
writel(drvdata->pdata->wdt_en_bit, drvdata->base + WDT_EN);
writel(0x1, drvdata->base + drvdata->pdata->timer_offset);
writel(0x1, drvdata->base + drvdata->pdata->set_offset);
return 0;
}
static const struct watchdog_info ls1x_wdt_info = {
.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
.identity = "Loongson1 Watchdog",
};
static const struct watchdog_ops ls1x_wdt_ops = {
.owner = THIS_MODULE,
.start = ls1x_wdt_start,
.stop = ls1x_wdt_stop,
.ping = ls1x_wdt_ping,
.set_timeout = ls1x_wdt_set_timeout,
.restart = ls1x_wdt_restart,
};
static int ls1x_wdt_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct ls1x_wdt_drvdata *drvdata;
struct watchdog_device *ls1x_wdt;
unsigned long clk_rate;
drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
if (!drvdata)
return -ENOMEM;
platform_set_drvdata(pdev, drvdata);
drvdata->pdata = of_device_get_match_data(dev);
drvdata->base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(drvdata->base))
return PTR_ERR(drvdata->base);
drvdata->clk = devm_clk_get_enabled(dev, NULL);
if (IS_ERR(drvdata->clk))
return PTR_ERR(drvdata->clk);
clk_rate = clk_get_rate(drvdata->clk);
if (!clk_rate)
return -EINVAL;
drvdata->clk_rate = clk_rate;
ls1x_wdt = &drvdata->wdt;
ls1x_wdt->info = &ls1x_wdt_info;
ls1x_wdt->ops = &ls1x_wdt_ops;
ls1x_wdt->timeout = DEFAULT_HEARTBEAT;
ls1x_wdt->min_timeout = 1;
ls1x_wdt->max_hw_heartbeat_ms = U32_MAX / clk_rate * 1000;
ls1x_wdt->parent = dev;
watchdog_init_timeout(ls1x_wdt, heartbeat, dev);
watchdog_set_nowayout(ls1x_wdt, nowayout);
watchdog_set_drvdata(ls1x_wdt, drvdata);
return devm_watchdog_register_device(dev, &drvdata->wdt);
}
static int ls1x_wdt_resume(struct device *dev)
{
struct ls1x_wdt_drvdata *data = dev_get_drvdata(dev);
if (watchdog_active(&data->wdt))
ls1x_wdt_start(&data->wdt);
return 0;
}
static int ls1x_wdt_suspend(struct device *dev)
{
struct ls1x_wdt_drvdata *data = dev_get_drvdata(dev);
if (watchdog_active(&data->wdt))
ls1x_wdt_stop(&data->wdt);
return 0;
}
static DEFINE_SIMPLE_DEV_PM_OPS(ls1x_wdt_pm_ops, ls1x_wdt_suspend, ls1x_wdt_resume);
static const struct of_device_id ls1x_wdt_dt_ids[] = {
{ .compatible = "loongson,ls1b-wdt", .data = &ls1b_wdt_pdata },
{ .compatible = "loongson,ls1c-wdt", .data = &ls1b_wdt_pdata },
{ .compatible = "loongson,ls2k0300-wdt", .data = &ls2k0300_wdt_pdata },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, ls1x_wdt_dt_ids);
static struct platform_driver ls1x_wdt_driver = {
.probe = ls1x_wdt_probe,
.driver = {
.name = "ls1x-wdt",
.of_match_table = ls1x_wdt_dt_ids,
.pm = pm_ptr(&ls1x_wdt_pm_ops),
},
};
module_platform_driver(ls1x_wdt_driver);
MODULE_AUTHOR("Yang Ling <gnaygnil@gmail.com>");
MODULE_AUTHOR("Binbin Zhou <zhoubinbin@loongson.cn>");
MODULE_DESCRIPTION("Loongson Watchdog Driver");
MODULE_LICENSE("GPL");
|
