This source file includes following definitions.
- imx_sc_wdt_ping
- imx_sc_wdt_start
- imx_sc_wdt_stop
- imx_sc_wdt_set_timeout
- imx_sc_wdt_set_pretimeout
- imx_sc_wdt_notify
- imx_sc_wdt_action
- imx_sc_wdt_probe
- imx_sc_wdt_suspend
- imx_sc_wdt_resume
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6 #include <linux/arm-smccc.h>
7 #include <linux/firmware/imx/sci.h>
8 #include <linux/io.h>
9 #include <linux/init.h>
10 #include <linux/kernel.h>
11 #include <linux/module.h>
12 #include <linux/moduleparam.h>
13 #include <linux/of.h>
14 #include <linux/platform_device.h>
15 #include <linux/reboot.h>
16 #include <linux/watchdog.h>
17
18 #define DEFAULT_TIMEOUT 60
19
20
21
22
23
24 #define MAX_TIMEOUT 128
25
26 #define IMX_SIP_TIMER 0xC2000002
27 #define IMX_SIP_TIMER_START_WDOG 0x01
28 #define IMX_SIP_TIMER_STOP_WDOG 0x02
29 #define IMX_SIP_TIMER_SET_WDOG_ACT 0x03
30 #define IMX_SIP_TIMER_PING_WDOG 0x04
31 #define IMX_SIP_TIMER_SET_TIMEOUT_WDOG 0x05
32 #define IMX_SIP_TIMER_GET_WDOG_STAT 0x06
33 #define IMX_SIP_TIMER_SET_PRETIME_WDOG 0x07
34
35 #define SC_TIMER_WDOG_ACTION_PARTITION 0
36
37 #define SC_IRQ_WDOG 1
38 #define SC_IRQ_GROUP_WDOG 1
39
40 static bool nowayout = WATCHDOG_NOWAYOUT;
41 module_param(nowayout, bool, 0000);
42 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
43 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
44
45 struct imx_sc_wdt_device {
46 struct watchdog_device wdd;
47 struct notifier_block wdt_notifier;
48 };
49
50 static int imx_sc_wdt_ping(struct watchdog_device *wdog)
51 {
52 struct arm_smccc_res res;
53
54 arm_smccc_smc(IMX_SIP_TIMER, IMX_SIP_TIMER_PING_WDOG,
55 0, 0, 0, 0, 0, 0, &res);
56
57 return 0;
58 }
59
60 static int imx_sc_wdt_start(struct watchdog_device *wdog)
61 {
62 struct arm_smccc_res res;
63
64 arm_smccc_smc(IMX_SIP_TIMER, IMX_SIP_TIMER_START_WDOG,
65 0, 0, 0, 0, 0, 0, &res);
66 if (res.a0)
67 return -EACCES;
68
69 arm_smccc_smc(IMX_SIP_TIMER, IMX_SIP_TIMER_SET_WDOG_ACT,
70 SC_TIMER_WDOG_ACTION_PARTITION,
71 0, 0, 0, 0, 0, &res);
72 return res.a0 ? -EACCES : 0;
73 }
74
75 static int imx_sc_wdt_stop(struct watchdog_device *wdog)
76 {
77 struct arm_smccc_res res;
78
79 arm_smccc_smc(IMX_SIP_TIMER, IMX_SIP_TIMER_STOP_WDOG,
80 0, 0, 0, 0, 0, 0, &res);
81
82 return res.a0 ? -EACCES : 0;
83 }
84
85 static int imx_sc_wdt_set_timeout(struct watchdog_device *wdog,
86 unsigned int timeout)
87 {
88 struct arm_smccc_res res;
89
90 wdog->timeout = timeout;
91 arm_smccc_smc(IMX_SIP_TIMER, IMX_SIP_TIMER_SET_TIMEOUT_WDOG,
92 timeout * 1000, 0, 0, 0, 0, 0, &res);
93
94 return res.a0 ? -EACCES : 0;
95 }
96
97 static int imx_sc_wdt_set_pretimeout(struct watchdog_device *wdog,
98 unsigned int pretimeout)
99 {
100 struct arm_smccc_res res;
101
102
103
104
105
106
107 arm_smccc_smc(IMX_SIP_TIMER, IMX_SIP_TIMER_SET_PRETIME_WDOG,
108 (wdog->timeout - pretimeout) * 1000, 0, 0, 0,
109 0, 0, &res);
110 if (res.a0)
111 return -EACCES;
112
113 wdog->pretimeout = pretimeout;
114
115 return 0;
116 }
117
118 static int imx_sc_wdt_notify(struct notifier_block *nb,
119 unsigned long event, void *group)
120 {
121 struct imx_sc_wdt_device *imx_sc_wdd =
122 container_of(nb,
123 struct imx_sc_wdt_device,
124 wdt_notifier);
125
126 if (event & SC_IRQ_WDOG &&
127 *(u8 *)group == SC_IRQ_GROUP_WDOG)
128 watchdog_notify_pretimeout(&imx_sc_wdd->wdd);
129
130 return 0;
131 }
132
133 static void imx_sc_wdt_action(void *data)
134 {
135 struct notifier_block *wdt_notifier = data;
136
137 imx_scu_irq_unregister_notifier(wdt_notifier);
138 imx_scu_irq_group_enable(SC_IRQ_GROUP_WDOG,
139 SC_IRQ_WDOG,
140 false);
141 }
142
143 static const struct watchdog_ops imx_sc_wdt_ops = {
144 .owner = THIS_MODULE,
145 .start = imx_sc_wdt_start,
146 .stop = imx_sc_wdt_stop,
147 .ping = imx_sc_wdt_ping,
148 .set_timeout = imx_sc_wdt_set_timeout,
149 .set_pretimeout = imx_sc_wdt_set_pretimeout,
150 };
151
152 static struct watchdog_info imx_sc_wdt_info = {
153 .identity = "i.MX SC watchdog timer",
154 .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING |
155 WDIOF_MAGICCLOSE,
156 };
157
158 static int imx_sc_wdt_probe(struct platform_device *pdev)
159 {
160 struct imx_sc_wdt_device *imx_sc_wdd;
161 struct watchdog_device *wdog;
162 struct device *dev = &pdev->dev;
163 int ret;
164
165 imx_sc_wdd = devm_kzalloc(dev, sizeof(*imx_sc_wdd), GFP_KERNEL);
166 if (!imx_sc_wdd)
167 return -ENOMEM;
168
169 platform_set_drvdata(pdev, imx_sc_wdd);
170
171 wdog = &imx_sc_wdd->wdd;
172 wdog->info = &imx_sc_wdt_info;
173 wdog->ops = &imx_sc_wdt_ops;
174 wdog->min_timeout = 1;
175 wdog->max_timeout = MAX_TIMEOUT;
176 wdog->parent = dev;
177 wdog->timeout = DEFAULT_TIMEOUT;
178
179 watchdog_init_timeout(wdog, 0, dev);
180
181 ret = imx_sc_wdt_set_timeout(wdog, wdog->timeout);
182 if (ret)
183 return ret;
184
185 watchdog_stop_on_reboot(wdog);
186 watchdog_stop_on_unregister(wdog);
187
188 ret = devm_watchdog_register_device(dev, wdog);
189 if (ret)
190 return ret;
191
192 ret = imx_scu_irq_group_enable(SC_IRQ_GROUP_WDOG,
193 SC_IRQ_WDOG,
194 true);
195 if (ret) {
196 dev_warn(dev, "Enable irq failed, pretimeout NOT supported\n");
197 return 0;
198 }
199
200 imx_sc_wdd->wdt_notifier.notifier_call = imx_sc_wdt_notify;
201 ret = imx_scu_irq_register_notifier(&imx_sc_wdd->wdt_notifier);
202 if (ret) {
203 imx_scu_irq_group_enable(SC_IRQ_GROUP_WDOG,
204 SC_IRQ_WDOG,
205 false);
206 dev_warn(dev,
207 "Register irq notifier failed, pretimeout NOT supported\n");
208 return 0;
209 }
210
211 ret = devm_add_action_or_reset(dev, imx_sc_wdt_action,
212 &imx_sc_wdd->wdt_notifier);
213 if (!ret)
214 imx_sc_wdt_info.options |= WDIOF_PRETIMEOUT;
215 else
216 dev_warn(dev, "Add action failed, pretimeout NOT supported\n");
217
218 return 0;
219 }
220
221 static int __maybe_unused imx_sc_wdt_suspend(struct device *dev)
222 {
223 struct imx_sc_wdt_device *imx_sc_wdd = dev_get_drvdata(dev);
224
225 if (watchdog_active(&imx_sc_wdd->wdd))
226 imx_sc_wdt_stop(&imx_sc_wdd->wdd);
227
228 return 0;
229 }
230
231 static int __maybe_unused imx_sc_wdt_resume(struct device *dev)
232 {
233 struct imx_sc_wdt_device *imx_sc_wdd = dev_get_drvdata(dev);
234
235 if (watchdog_active(&imx_sc_wdd->wdd))
236 imx_sc_wdt_start(&imx_sc_wdd->wdd);
237
238 return 0;
239 }
240
241 static SIMPLE_DEV_PM_OPS(imx_sc_wdt_pm_ops,
242 imx_sc_wdt_suspend, imx_sc_wdt_resume);
243
244 static const struct of_device_id imx_sc_wdt_dt_ids[] = {
245 { .compatible = "fsl,imx-sc-wdt", },
246 { }
247 };
248 MODULE_DEVICE_TABLE(of, imx_sc_wdt_dt_ids);
249
250 static struct platform_driver imx_sc_wdt_driver = {
251 .probe = imx_sc_wdt_probe,
252 .driver = {
253 .name = "imx-sc-wdt",
254 .of_match_table = imx_sc_wdt_dt_ids,
255 .pm = &imx_sc_wdt_pm_ops,
256 },
257 };
258 module_platform_driver(imx_sc_wdt_driver);
259
260 MODULE_AUTHOR("Robin Gong <yibin.gong@nxp.com>");
261 MODULE_DESCRIPTION("NXP i.MX system controller watchdog driver");
262 MODULE_LICENSE("GPL v2");