4  * SPDX-License-Identifier: Apache-2.0
18  *            +---------------------+    +-----------------+
19  *  LFCLK --->| T0 Prescale Counter |-+->| 16-Bit T0 Timer |--------> T0 Timer
21  *            +---------------------+ |  +-----------------+
22  *  +---------------------------------+
24  *  |    +-------------------+    +-----------------+
25  *  +--->| Watchdog Prescale |--->| 8-Bit Watchdog  |-----> Watchdog Event/Reset
27  *       +-------------------+    +-----------------+
49  * Maximum watchdog window time. Keep the timer and watchdog clock prescaler
50  * (TWCP) to 0x5. Since the watchdog counter is 8-bits, maximum time supported
73 	/* t0 timer wake-up input source configuration */
79 	/* Timestamp of touching watchdog last time */
92 #define HAL_INSTANCE(dev) ((struct twd_reg *)((const struct wdt_npcx_config *)(dev)->config)->base)
101 	inst->T0CSR = (inst->T0CSR & ~BIT(NPCX_T0CSR_WDRST_STS)) |  in wdt_t0out_reload()
105 	while (IS_BIT_SET(inst->T0CSR, NPCX_T0CSR_RST)) {  in wdt_t0out_reload()
106 		if (k_uptime_get() - st > NPCX_T0CSR_RST_TIMEOUT) {  in wdt_t0out_reload()
108 			if (IS_BIT_SET(inst->T0CSR, NPCX_T0CSR_RST)) {  in wdt_t0out_reload()
110 				return -ETIMEDOUT;  in wdt_t0out_reload()
125 	while (IS_BIT_SET(inst->T0CSR, NPCX_T0CSR_WD_RUN)) {  in wdt_wait_stopped()
126 		if (k_uptime_get() - st > NPCX_WATCHDOG_STOP_TIMEOUT) {  in wdt_wait_stopped()
128 			if (IS_BIT_SET(inst->T0CSR, NPCX_T0CSR_WD_RUN)) {  in wdt_wait_stopped()
130 				return -ETIMEDOUT;  in wdt_wait_stopped()
141 	struct wdt_npcx_data *const data = dev->data;  in wdt_t0out_isr()
145 		CONFIG_WDT_NPCX_WARNING_LEADING_TIME_MS, wui->table, wui->group, wui->bit);  in wdt_t0out_isr()
148 	if (data->cb) {  in wdt_t0out_isr()
149 		data->cb(dev, 0);  in wdt_t0out_isr()
155 	const struct wdt_npcx_config *const config = dev->config;  in wdt_config_t0out_interrupt()
158 	npcx_miwu_init_dev_callback(&miwu_cb, &config->t0out, wdt_t0out_isr,  in wdt_config_t0out_interrupt()
163 	 * Configure the T0 wake-up event triggered from a rising edge  in wdt_config_t0out_interrupt()
166 	npcx_miwu_interrupt_configure(&config->t0out,  in wdt_config_t0out_interrupt()
174 	struct wdt_npcx_data *const data = dev->data;  in wdt_npcx_install_timeout()
178 	if (IS_BIT_SET(inst->T0CSR, NPCX_T0CSR_WD_RUN)) {  in wdt_npcx_install_timeout()
179 		return -EBUSY;  in wdt_npcx_install_timeout()
183 	if (cfg->window.min != 0) {  in wdt_npcx_install_timeout()
184 		data->timeout_installed = false;  in wdt_npcx_install_timeout()
185 		return -EINVAL;  in wdt_npcx_install_timeout()
189 	 * Since the watchdog counter in npcx series is 8-bits, maximum time  in wdt_npcx_install_timeout()
191 	 * allowed range of 1-8000 in milliseconds. Check if the provided value  in wdt_npcx_install_timeout()
194 	if (cfg->window.max > NPCX_WDT_MAX_WND_TIME || cfg->window.max == 0) {  in wdt_npcx_install_timeout()
195 		data->timeout_installed = false;  in wdt_npcx_install_timeout()
196 		return -EINVAL;  in wdt_npcx_install_timeout()
200 	data->timeout = cfg->window.max;  in wdt_npcx_install_timeout()
203 	data->cb = cfg->callback;  in wdt_npcx_install_timeout()
204 	data->timeout_installed = true;  in wdt_npcx_install_timeout()
212 	const struct wdt_npcx_config *const config = dev->config;  in wdt_npcx_setup()
213 	struct wdt_npcx_data *const data = dev->data;  in wdt_npcx_setup()
219 	/* Disable irq of t0-out expired event first */  in wdt_npcx_setup()
220 	npcx_miwu_irq_disable(&config->t0out);  in wdt_npcx_setup()
222 	if (!data->timeout_installed) {  in wdt_npcx_setup()
224 		return -EINVAL;  in wdt_npcx_setup()
227 	if (IS_BIT_SET(inst->T0CSR, NPCX_T0CSR_WD_RUN)) {  in wdt_npcx_setup()
229 		return -EBUSY;  in wdt_npcx_setup()
234 		return -ENOTSUP;  in wdt_npcx_setup()
246 	 * Then the counter value is timeout/0.976 - 1.  in wdt_npcx_setup()
248 	inst->TWDT0 = MAX(DIV_ROUND_UP(data->timeout * NPCX_WDT_CLK,  in wdt_npcx_setup()
249 				32 * 1000) - 1, 1);  in wdt_npcx_setup()
251 	/* Configure 8-bit watchdog counter  in wdt_npcx_setup()
252 	 * Change the prescaler of watchdog clock for larger timeout  in wdt_npcx_setup()
254 	wd_cnt = DIV_ROUND_UP((data->timeout + CONFIG_WDT_NPCX_WARNING_LEADING_TIME_MS) *  in wdt_npcx_setup()
262 	 * prescaler  in wdt_npcx_setup()
264 	wdcp = LOG2(pre_scal - 1) + 1;  in wdt_npcx_setup()
267 	inst->WDCP = wdcp;  in wdt_npcx_setup()
268 	inst->WDCNT = wd_cnt / pre_scal;  in wdt_npcx_setup()
270 	LOG_DBG("WDT setup: TWDT0, WDCNT are %d, %d", inst->TWDT0, inst->WDCNT);  in wdt_npcx_setup()
278 	/* Enable irq of t0-out expired event */  in wdt_npcx_setup()
279 	npcx_miwu_irq_enable(&config->t0out);  in wdt_npcx_setup()
286 	const struct wdt_npcx_config *const config = dev->config;  in wdt_npcx_disable()
287 	struct wdt_npcx_data *const data = dev->data;  in wdt_npcx_disable()
295 	min_wnd_t = DIV_ROUND_UP(3 * NPCX_WDT_CLK, 32 * (1 << inst->WDCP));  in wdt_npcx_disable()
296 	while (k_uptime_get() - data->last_watchdog_touch < min_wnd_t) {  in wdt_npcx_disable()
304 	inst->WDSDM = 0x87;  in wdt_npcx_disable()
305 	inst->WDSDM = 0x61;  in wdt_npcx_disable()
306 	inst->WDSDM = 0x63;  in wdt_npcx_disable()
308 	/* Disable irq of t0-out expired event and mark it uninstalled */  in wdt_npcx_disable()
309 	npcx_miwu_irq_disable(&config->t0out);  in wdt_npcx_disable()
310 	data->timeout_installed = false;  in wdt_npcx_disable()
319 	struct wdt_npcx_data *const data = dev->data;  in wdt_npcx_feed()
323 	inst->WDSDM = 0x5C;  in wdt_npcx_feed()
324 	data->last_watchdog_touch = k_uptime_get();  in wdt_npcx_feed()
348 	 * [7:6]- Reserved = 0  in wdt_npcx_init()
349 	 * [5]  - WDSDME   = 1: Feed watchdog by writing 5Ch to WDSDM  in wdt_npcx_init()
350 	 * [4]  - WDCT0I   = 1: Select T0IN as watchdog prescaler clock  in wdt_npcx_init()
351 	 * [3]  - LWDCNT   = 0: Don't lock WDCNT register  in wdt_npcx_init()
352 	 * [2]  - LTWDT0   = 0: Don't lock TWDT0 register  in wdt_npcx_init()
353 	 * [1]  - LTWCP    = 0: Don't lock TWCP register  in wdt_npcx_init()
354 	 * [0]  - LTWCFG   = 0: Don't lock TWCFG register  in wdt_npcx_init()
356 	inst->TWCFG = BIT(NPCX_TWCFG_WDSDME) | BIT(NPCX_TWCFG_WDCT0I);  in wdt_npcx_init()
359 	inst->T0CSR = (inst->T0CSR & ~BIT(NPCX_T0CSR_WDRST_STS)) |  in wdt_npcx_init()
363 	 * - T0 Timer freq is LFCLK/32 Hz  in wdt_npcx_init()
364 	 * - Watchdog freq is T0CLK/32 Hz (ie. LFCLK/1024 Hz)  in wdt_npcx_init()
366 	inst->WDCP = 0x05; /* Prescaler is 32 in Watchdog Timer */  in wdt_npcx_init()
367 	inst->TWCP = 0x05; /* Prescaler is 32 in T0 Timer */  in wdt_npcx_init()