1 /**
2 ******************************************************************************
3 * @file stm32n6xx_hal_iwdg.c
4 * @author MCD Application Team
5 * @brief IWDG HAL module driver.
6 * This file provides firmware functions to manage the following
7 * functionalities of the Independent Watchdog (IWDG) peripheral:
8 * + Initialization and Start functions
9 * + IO operation functions
10 *
11 ******************************************************************************
12 * @attention
13 *
14 * Copyright (c) 2023 STMicroelectronics.
15 * All rights reserved.
16 *
17 * This software is licensed under terms that can be found in the LICENSE file
18 * in the root directory of this software component.
19 * If no LICENSE file comes with this software, it is provided AS-IS.
20 *
21 ******************************************************************************
22 @verbatim
23 ==============================================================================
24 ##### IWDG Generic features #####
25 ==============================================================================
26 [..]
27 (+) The IWDG can be started by either software or hardware (configurable
28 through option byte).
29
30 (+) The IWDG is clocked by the Low-Speed Internal clock (LSI) and thus stays
31 active even if the main clock fails.
32
33 (+) Once the IWDG is started, the LSI is forced ON and both cannot be
34 disabled. The counter starts counting down from the reset value (0xFFF).
35 When it reaches the end of count value (0x000) a reset signal is
36 generated (IWDG reset).
37
38 (+) Whenever the key value 0x0000 AAAA is written in the IWDG_KR register,
39 the IWDG_RLR value is reloaded into the counter and the watchdog reset
40 is prevented.
41
42 (+) The IWDG is implemented in the VDD voltage domain that is still functional
43 in STOP and STANDBY mode (IWDG reset can wake up the CPU from STANDBY).
44 IWDGRST flag in RCC_CSR register can be used to inform when an IWDG
45 reset occurs.
46
47 (+) Debug mode: When the microcontroller enters debug mode (core halted),
48 the IWDG counter either continues to work normally or stops, depending
49 on DBG_IWDG_STOP configuration bit in DBG module, accessible through
50 __HAL_DBGMCU_FREEZE_IWDG() and __HAL_DBGMCU_UNFREEZE_IWDG() macros.
51
52 [..] Min-max timeout value @32KHz (LSI): ~125us / ~131.04s
53 The IWDG timeout may vary due to LSI clock frequency dispersion.
54 STM32N6xx devices provide the capability to measure the LSI clock
55 frequency (LSI clock is internally connected to TIM16 CH1 input capture).
56 The measured value can be used to have an IWDG timeout with an
57 acceptable accuracy.
58
59 [..] Default timeout value (necessary for IWDG_SR status register update):
60 Constant LSI_VALUE is defined based on the nominal LSI clock frequency.
61 This frequency being subject to variations as mentioned above, the
62 default timeout value (defined through constant HAL_IWDG_DEFAULT_TIMEOUT
63 below) may become too short or too long.
64 In such cases, this default timeout value can be tuned by redefining
65 the constant LSI_VALUE at user-application level (based, for instance,
66 on the measured LSI clock frequency as explained above).
67
68 ##### How to use this driver #####
69 ==============================================================================
70 [..]
71 (#) Register callback to treat Iwdg interrupt and MspInit using HAL_IWDG_RegisterCallback().
72 (++) Provide exiting handle as first parameter.
73 (++) Provide which callback will be registered using one value from
74 HAL_IWDG_CallbackIDTypeDef.
75 (++) Provide callback function pointer.
76
77 (#) Use IWDG using HAL_IWDG_Init() function to :
78 (++) Enable instance by writing Start keyword in IWDG_KEY register. LSI
79 clock is forced ON and IWDG counter starts counting down.
80 (++) Enable write access to configuration registers:
81 IWDG_PR, IWDG_RLR, IWDG_WINR and EWCR.
82 (++) Configure the IWDG prescaler and counter reload value. This reload
83 value will be loaded in the IWDG counter each time the watchdog is
84 reloaded, then the IWDG will start counting down from this value.
85 (++) Depending on window parameter:
86 (+++) If Window Init parameter is same as Window register value,
87 nothing more is done but reload counter value in order to exit
88 function with exact time base.
89 (+++) Else modify Window register. This will automatically reload
90 watchdog counter.
91 (++) Depending on Early Wakeup Interrupt parameter:
92 (+++) If EWI is set to disable, comparator is set to 0, interrupt is
93 disable & flag is clear.
94 (+++) Else modify EWCR register, setting comparator value, enable
95 interrupt & clear flag.
96 (++) Wait for status flags to be reset.
97
98 (#) Then the application program must refresh the IWDG counter at regular
99 intervals during normal operation to prevent an MCU reset, using
100 HAL_IWDG_Refresh() function.
101
102 *** IWDG HAL driver macros list ***
103 ====================================
104 [..]
105 Below the list of most used macros in IWDG HAL driver:
106 (+) __HAL_IWDG_START: Enable the IWDG peripheral
107 (+) __HAL_IWDG_RELOAD_COUNTER: Reloads IWDG counter with value defined in
108 the reload register
109
110 @endverbatim
111 */
112
113 /* Includes ------------------------------------------------------------------*/
114 #include "stm32n6xx_hal.h"
115
116 /** @addtogroup STM32N6xx_HAL_Driver
117 * @{
118 */
119
120 #ifdef HAL_IWDG_MODULE_ENABLED
121 /** @addtogroup IWDG
122 * @brief IWDG HAL module driver.
123 * @{
124 */
125
126 /* Private typedef -----------------------------------------------------------*/
127 /* Private define ------------------------------------------------------------*/
128 /** @defgroup IWDG_Private_Defines IWDG Private Defines
129 * @{
130 */
131 /* Status register needs up to 5 LSI clock periods to be updated. However a
132 synchronisation is added on prescaled LSI clock rising edge, so we only
133 consider a highest prescaler cycle.
134 The timeout value is calculated using the highest prescaler (1024) and
135 the LSI_VALUE constant. The value of this constant can be changed by the user
136 to take into account possible LSI clock period variations.
137 The timeout value is multiplied by 1000 to be converted in milliseconds.
138 LSI startup time is also considered here by adding LSI_STARTUP_TIME
139 converted in milliseconds. */
140 #define HAL_IWDG_DEFAULT_TIMEOUT (((1UL * 1024UL * 1000UL) / LSI_VALUE) + ((LSI_STARTUP_TIME / 1000UL) + 1UL))
141 #define IWDG_KERNEL_UPDATE_FLAGS (IWDG_SR_EWU | IWDG_SR_WVU | IWDG_SR_RVU | IWDG_SR_PVU)
142 /**
143 * @}
144 */
145
146 /* Private macro -------------------------------------------------------------*/
147 /* Private variables ---------------------------------------------------------*/
148 /* Private function prototypes -----------------------------------------------*/
149 /* Exported functions --------------------------------------------------------*/
150
151 /** @addtogroup IWDG_Exported_Functions
152 * @{
153 */
154
155 /** @addtogroup IWDG_Exported_Functions_Group1
156 * @brief Initialization and Start functions.
157 *
158 @verbatim
159 ===============================================================================
160 ##### Initialization and Start functions #####
161 ===============================================================================
162 [..] This section provides functions allowing to:
163 (+) Initialize the IWDG according to the specified parameters in the
164 IWDG_InitTypeDef of associated handle.
165 (+) Manage Window option.
166 (+) Once initialization is performed in HAL_IWDG_Init function, Watchdog
167 is reloaded in order to exit function with correct time base.
168
169 @endverbatim
170 * @{
171 */
172
173 /**
174 * @brief Initialize the IWDG according to the specified parameters in the
175 * IWDG_InitTypeDef and start watchdog. Before exiting function,
176 * watchdog is refreshed in order to have correct time base.
177 * @param hiwdg pointer to a IWDG_HandleTypeDef structure that contains
178 * the configuration information for the specified IWDG module.
179 * @retval HAL status
180 */
HAL_IWDG_Init(IWDG_HandleTypeDef * hiwdg)181 HAL_StatusTypeDef HAL_IWDG_Init(IWDG_HandleTypeDef *hiwdg)
182 {
183 uint32_t tickstart;
184
185 /* Check the IWDG handle allocation */
186 if (hiwdg == NULL)
187 {
188 return HAL_ERROR;
189 }
190
191 /* Check the parameters */
192 assert_param(IS_IWDG_ALL_INSTANCE(hiwdg->Instance));
193 assert_param(IS_IWDG_PRESCALER(hiwdg->Init.Prescaler));
194 assert_param(IS_IWDG_RELOAD(hiwdg->Init.Reload));
195 assert_param(IS_IWDG_WINDOW(hiwdg->Init.Window));
196 assert_param(IS_IWDG_EWI(hiwdg->Init.EWI));
197
198 #if (USE_HAL_IWDG_REGISTER_CALLBACKS == 1)
199 /* Reset Callback pointers */
200 if (hiwdg->EwiCallback == NULL)
201 {
202 hiwdg->EwiCallback = HAL_IWDG_EarlyWakeupCallback;
203 }
204 if (hiwdg->MspInitCallback == NULL)
205 {
206 hiwdg->MspInitCallback = HAL_IWDG_MspInit;
207 }
208
209 /* Init the low level hardware */
210 hiwdg->MspInitCallback(hiwdg);
211 #else
212 /* Init the low level hardware */
213 HAL_IWDG_MspInit(hiwdg);
214 #endif /* USE_HAL_IWDG_REGISTER_CALLBACKS */
215
216 /* Enable IWDG. LSI is turned on automatically */
217 __HAL_IWDG_START(hiwdg);
218
219 /* Enable write access to IWDG_PR, IWDG_RLR, IWDG_WINR and EWCR registers by writing
220 0x5555 in KR */
221 IWDG_ENABLE_WRITE_ACCESS(hiwdg);
222
223 /* Write to IWDG registers the Prescaler & Reload values to work with */
224 hiwdg->Instance->PR = hiwdg->Init.Prescaler;
225 hiwdg->Instance->RLR = hiwdg->Init.Reload;
226
227 /* Check Reload update flag, before performing any reload of the counter, else previous value
228 will be taken. */
229 tickstart = HAL_GetTick();
230
231 /* Wait for register to be updated */
232 while ((hiwdg->Instance->SR & IWDG_SR_RVU) != 0x00u)
233 {
234 if ((HAL_GetTick() - tickstart) > HAL_IWDG_DEFAULT_TIMEOUT)
235 {
236 if ((hiwdg->Instance->SR & IWDG_SR_RVU) != 0x00u)
237 {
238 return HAL_TIMEOUT;
239 }
240 }
241 }
242
243 /* Acknowledge the early wakeup interrupt in any cases. it clears the EWIF flag in SR register */
244 hiwdg->Instance->ICR = IWDG_ICR_EWIC;
245
246 if (hiwdg->Init.EWI != IWDG_EWI_DISABLE)
247 {
248 /* EWI comparator value different from 0, Enable the early wakeup interrupt
249 * Set Watchdog Early Wakeup Comparator value
250 */
251 hiwdg->Instance->EWCR = IWDG_EWCR_EWIE | hiwdg->Init.EWI;
252 }
253 else
254 {
255 hiwdg->Instance->EWCR = 0x00U;
256 }
257 /* Check pending flag, if previous update not done, return timeout */
258 tickstart = HAL_GetTick();
259
260 /* Wait for register to be updated */
261 while ((hiwdg->Instance->SR & IWDG_KERNEL_UPDATE_FLAGS) != 0x00u)
262 {
263 if ((HAL_GetTick() - tickstart) > HAL_IWDG_DEFAULT_TIMEOUT)
264 {
265 if ((hiwdg->Instance->SR & IWDG_KERNEL_UPDATE_FLAGS) != 0x00u)
266 {
267 return HAL_TIMEOUT;
268 }
269 }
270 }
271
272 /* If window parameter is different than current value, modify window
273 register */
274 if (hiwdg->Instance->WINR != hiwdg->Init.Window)
275 {
276 /* Write to IWDG WINR the IWDG_Window value to compare with. In any case,
277 even if window feature is disabled, Watchdog will be reloaded by writing
278 windows register */
279 hiwdg->Instance->WINR = hiwdg->Init.Window;
280 }
281 else
282 {
283 /* Reload IWDG counter with value defined in the reload register */
284 __HAL_IWDG_RELOAD_COUNTER(hiwdg);
285 }
286
287 /* Return function status */
288 return HAL_OK;
289 }
290
291
292 /**
293 * @brief Initialize the IWDG MSP.
294 * @param hiwdg pointer to a IWDG_HandleTypeDef structure that contains
295 * the configuration information for the specified IWDG module.
296 * @note When rewriting this function in user file, mechanism may be added
297 * to avoid multiple initialize when HAL_IWDG_Init function is called
298 * again to change parameters.
299 * @retval None
300 */
HAL_IWDG_MspInit(IWDG_HandleTypeDef * hiwdg)301 __weak void HAL_IWDG_MspInit(IWDG_HandleTypeDef *hiwdg)
302 {
303 /* Prevent unused argument(s) compilation warning */
304 UNUSED(hiwdg);
305
306 /* NOTE: This function should not be modified, when the callback is needed,
307 the HAL_IWDG_MspInit could be implemented in the user file
308 */
309 }
310
311
312 #if (USE_HAL_IWDG_REGISTER_CALLBACKS == 1)
313 /**
314 * @brief Register a User IWDG Callback
315 * To be used instead of the weak (surcharged) predefined callback
316 * @param hiwdg IWDG handle
317 * @param CallbackID ID of the callback to be registered
318 * This parameter can be one of the following values:
319 * @arg @ref HAL_IWDG_EWI_CB_ID Early WakeUp Interrupt Callback ID
320 * @arg @ref HAL_IWDG_MSPINIT_CB_ID MspInit callback ID
321 * @param pCallback pointer to the Callback function
322 * @retval status
323 */
HAL_IWDG_RegisterCallback(IWDG_HandleTypeDef * hiwdg,HAL_IWDG_CallbackIDTypeDef CallbackID,pIWDG_CallbackTypeDef pCallback)324 HAL_StatusTypeDef HAL_IWDG_RegisterCallback(IWDG_HandleTypeDef *hiwdg, HAL_IWDG_CallbackIDTypeDef CallbackID,
325 pIWDG_CallbackTypeDef pCallback)
326 {
327 HAL_StatusTypeDef status = HAL_OK;
328
329 if (pCallback == NULL)
330 {
331 status = HAL_ERROR;
332 }
333 else
334 {
335 switch (CallbackID)
336 {
337 case HAL_IWDG_EWI_CB_ID:
338 hiwdg->EwiCallback = pCallback;
339 break;
340 case HAL_IWDG_MSPINIT_CB_ID:
341 hiwdg->MspInitCallback = pCallback;
342 break;
343
344 default:
345 status = HAL_ERROR;
346 break;
347 }
348 }
349
350 return status;
351 }
352
353
354 /**
355 * @brief Unregister a IWDG Callback
356 * IWDG Callback is redirected to the weak (surcharged) predefined callback
357 * @param hiwdg IWDG handle
358 * @param CallbackID ID of the callback to be registered
359 * This parameter can be one of the following values:
360 * @arg @ref HAL_IWDG_EWI_CB_ID Early WakeUp Interrupt Callback ID
361 * @arg @ref HAL_IWDG_MSPINIT_CB_ID MspInit callback ID
362 * @retval status
363 */
HAL_IWDG_UnRegisterCallback(IWDG_HandleTypeDef * hiwdg,HAL_IWDG_CallbackIDTypeDef CallbackID)364 HAL_StatusTypeDef HAL_IWDG_UnRegisterCallback(IWDG_HandleTypeDef *hiwdg, HAL_IWDG_CallbackIDTypeDef CallbackID)
365 {
366 HAL_StatusTypeDef status = HAL_OK;
367
368 switch (CallbackID)
369 {
370 case HAL_IWDG_EWI_CB_ID:
371 hiwdg->EwiCallback = HAL_IWDG_EarlyWakeupCallback;
372 break;
373 case HAL_IWDG_MSPINIT_CB_ID:
374 hiwdg->MspInitCallback = HAL_IWDG_MspInit;
375 break;
376
377 default:
378 status = HAL_ERROR;
379 break;
380 }
381
382 return status;
383 }
384 #endif /* USE_HAL_IWDG_REGISTER_CALLBACKS */
385
386
387 /**
388 * @}
389 */
390
391
392 /** @addtogroup IWDG_Exported_Functions_Group2
393 * @brief IO operation functions
394 *
395 @verbatim
396 ===============================================================================
397 ##### IO operation functions #####
398 ===============================================================================
399 [..] This section provides functions allowing to:
400 (+) Refresh the IWDG.
401
402 @endverbatim
403 * @{
404 */
405
406 /**
407 * @brief Refresh the IWDG.
408 * @param hiwdg pointer to a IWDG_HandleTypeDef structure that contains
409 * the configuration information for the specified IWDG module.
410 * @retval HAL status
411 */
HAL_IWDG_Refresh(IWDG_HandleTypeDef * hiwdg)412 HAL_StatusTypeDef HAL_IWDG_Refresh(IWDG_HandleTypeDef *hiwdg)
413 {
414 /* Reload IWDG counter with value defined in the reload register */
415 __HAL_IWDG_RELOAD_COUNTER(hiwdg);
416
417 /* Return function status */
418 return HAL_OK;
419 }
420
421
422 /**
423 * @brief Get back IWDG running status
424 * @note This API allows to know if IWDG has been started by other master, thread
425 * or by hardware.
426 * @param hiwdg pointer to a IWDG_HandleTypeDef structure that contains
427 * the configuration information for the specified IWDG module.
428 * @retval can be one of following value :
429 * @arg @ref IWDG_STATUS_DISABLE
430 * @arg @ref IWDG_STATUS_ENABLE
431 */
HAL_IWDG_GetActiveStatus(const IWDG_HandleTypeDef * hiwdg)432 uint32_t HAL_IWDG_GetActiveStatus(const IWDG_HandleTypeDef *hiwdg)
433 {
434 uint32_t status;
435
436 /* Get back ONF flag */
437 status = (hiwdg->Instance->SR & IWDG_SR_ONF);
438
439 /* Return status */
440 return status;
441 }
442
443
444 /**
445 * @brief Handle IWDG interrupt request.
446 * @note The Early Wakeup Interrupt (EWI) can be used if specific safety operations
447 * or data logging must be performed before the actual reset is generated.
448 * The EWI interrupt is enabled by calling HAL_IWDG_Init function with
449 * EWIMode set to IWDG_EWI_ENABLE.
450 * When the downcounter reaches the value 0x40, and EWI interrupt is
451 * generated and the corresponding Interrupt Service Routine (ISR) can
452 * be used to trigger specific actions (such as communications or data
453 * logging), before resetting the device.
454 * @param hiwdg pointer to a IWDG_HandleTypeDef structure that contains
455 * the configuration information for the specified IWDG module.
456 * @retval None
457 */
HAL_IWDG_IRQHandler(IWDG_HandleTypeDef * hiwdg)458 void HAL_IWDG_IRQHandler(IWDG_HandleTypeDef *hiwdg)
459 {
460 /* Check if IWDG Early Wakeup Interrupt occurred */
461 if ((hiwdg->Instance->SR & IWDG_SR_EWIF) != 0x00u)
462 {
463 /* Clear the IWDG Early Wakeup flag */
464 hiwdg->Instance->ICR = IWDG_ICR_EWIC;
465
466 #if (USE_HAL_IWDG_REGISTER_CALLBACKS == 1)
467 /* Early Wakeup registered callback */
468 hiwdg->EwiCallback(hiwdg);
469 #else
470 /* Early Wakeup callback */
471 HAL_IWDG_EarlyWakeupCallback(hiwdg);
472 #endif /* USE_HAL_IWDG_REGISTER_CALLBACKS */
473 }
474 }
475
476
477 /**
478 * @brief IWDG Early Wakeup callback.
479 * @param hiwdg pointer to a IWDG_HandleTypeDef structure that contains
480 * the configuration information for the specified IWDG module.
481 * @retval None
482 */
HAL_IWDG_EarlyWakeupCallback(IWDG_HandleTypeDef * hiwdg)483 __weak void HAL_IWDG_EarlyWakeupCallback(IWDG_HandleTypeDef *hiwdg)
484 {
485 /* Prevent unused argument(s) compilation warning */
486 UNUSED(hiwdg);
487
488 /* NOTE: This function should not be modified, when the callback is needed,
489 the HAL_IWDG_EarlyWakeupCallback could be implemented in the user file
490 */
491 }
492
493
494 /**
495 * @}
496 */
497
498 /**
499 * @}
500 */
501
502 #endif /* HAL_IWDG_MODULE_ENABLED */
503 /**
504 * @}
505 */
506
507 /**
508 * @}
509 */
510
