1 // SPDX-License-Identifier: GPL-2.0+
3 * Copyright 2017 Google, Inc
6 #define LOG_CATEGORY UCLASS_WDT
16 #include <asm/global_data.h>
17 #include <dm/device-internal.h>
20 DECLARE_GLOBAL_DATA_PTR;
22 #define WATCHDOG_TIMEOUT_SECS (CONFIG_WATCHDOG_TIMEOUT_MSECS / 1000)
25 /* Timeout, in seconds, to configure this device to. */
28 * Time, in milliseconds, between calling the device's ->reset()
29 * method from watchdog_reset().
33 * Next time (as returned by get_timer(0)) to call
37 /* Whether watchdog_start() has been called on the device. */
41 static void init_watchdog_dev(struct udevice *dev)
43 struct wdt_priv *priv;
46 priv = dev_get_uclass_priv(dev);
48 if (IS_ENABLED(CONFIG_SYSRESET_WATCHDOG_AUTO)) {
49 ret = sysreset_register_wdt(dev);
51 printf("WDT: Failed to register %s for sysreset\n",
55 if (!IS_ENABLED(CONFIG_WATCHDOG_AUTOSTART)) {
56 printf("WDT: Not starting %s\n", dev->name);
60 ret = wdt_start(dev, priv->timeout * 1000, 0);
62 printf("WDT: Failed to start %s\n", dev->name);
66 printf("WDT: Started %s with%s servicing (%ds timeout)\n", dev->name,
67 IS_ENABLED(CONFIG_WATCHDOG) ? "" : "out", priv->timeout);
70 int initr_watchdog(void)
76 ret = uclass_get(UCLASS_WDT, &uc);
78 log_debug("Error getting UCLASS_WDT: %d\n", ret);
82 uclass_foreach_dev(dev, uc) {
83 ret = device_probe(dev);
85 log_debug("Error probing %s: %d\n", dev->name, ret);
88 init_watchdog_dev(dev);
91 gd->flags |= GD_FLG_WDT_READY;
95 int wdt_start(struct udevice *dev, u64 timeout_ms, ulong flags)
97 const struct wdt_ops *ops = device_get_ops(dev);
103 ret = ops->start(dev, timeout_ms, flags);
105 struct wdt_priv *priv = dev_get_uclass_priv(dev);
107 priv->running = true;
113 int wdt_stop(struct udevice *dev)
115 const struct wdt_ops *ops = device_get_ops(dev);
121 ret = ops->stop(dev);
123 struct wdt_priv *priv = dev_get_uclass_priv(dev);
125 priv->running = false;
131 int wdt_stop_all(void)
133 struct wdt_priv *priv;
138 ret = uclass_get(UCLASS_WDT, &uc);
142 uclass_foreach_dev(dev, uc) {
143 if (!device_active(dev))
145 priv = dev_get_uclass_priv(dev);
156 int wdt_reset(struct udevice *dev)
158 const struct wdt_ops *ops = device_get_ops(dev);
163 return ops->reset(dev);
166 int wdt_expire_now(struct udevice *dev, ulong flags)
169 const struct wdt_ops *ops;
171 debug("WDT Resetting: %lu\n", flags);
172 ops = device_get_ops(dev);
173 if (ops->expire_now) {
174 return ops->expire_now(dev, flags);
176 ret = wdt_start(dev, 1, flags);
187 #if defined(CONFIG_WATCHDOG)
189 * Called by macro WATCHDOG_RESET. This function be called *very* early,
190 * so we need to make sure, that the watchdog driver is ready before using
191 * it in this function.
193 void watchdog_reset(void)
195 struct wdt_priv *priv;
200 /* Exit if GD is not ready or watchdog is not initialized yet */
201 if (!gd || !(gd->flags & GD_FLG_WDT_READY))
204 if (uclass_get(UCLASS_WDT, &uc))
208 * All devices bound to the wdt uclass should have been probed
209 * in initr_watchdog(). But just in case something went wrong,
210 * check device_active() before accessing the uclass private
213 uclass_foreach_dev(dev, uc) {
214 if (!device_active(dev))
216 priv = dev_get_uclass_priv(dev);
219 /* Do not reset the watchdog too often */
221 if (time_after_eq(now, priv->next_reset)) {
222 priv->next_reset = now + priv->reset_period;
229 static int wdt_post_bind(struct udevice *dev)
231 #if defined(CONFIG_NEEDS_MANUAL_RELOC)
232 struct wdt_ops *ops = (struct wdt_ops *)device_get_ops(dev);
233 static int reloc_done;
237 ops->start += gd->reloc_off;
239 ops->stop += gd->reloc_off;
241 ops->reset += gd->reloc_off;
243 ops->expire_now += gd->reloc_off;
251 static int wdt_pre_probe(struct udevice *dev)
253 u32 timeout = WATCHDOG_TIMEOUT_SECS;
255 * Reset every 1000ms, or however often is required as
256 * indicated by a hw_margin_ms property.
258 ulong reset_period = 1000;
259 struct wdt_priv *priv;
261 if (CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA)) {
262 timeout = dev_read_u32_default(dev, "timeout-sec", timeout);
263 reset_period = dev_read_u32_default(dev, "hw_margin_ms",
264 4 * reset_period) / 4;
266 priv = dev_get_uclass_priv(dev);
267 priv->timeout = timeout;
268 priv->reset_period = reset_period;
270 * Pretend this device was last reset "long" ago so the first
271 * watchdog_reset will actually call its ->reset method.
273 priv->next_reset = get_timer(0);
278 UCLASS_DRIVER(wdt) = {
281 .flags = DM_UC_FLAG_SEQ_ALIAS,
282 .post_bind = wdt_post_bind,
283 .pre_probe = wdt_pre_probe,
284 .per_device_auto = sizeof(struct wdt_priv),