Test/try reverting watchdog changes

src/apps/rs232_expander_apps/aanderaa/CMakeLists.txt

@@ -14,6 +14,7 @@ set(APP_LIBS
 
 set(APP_DEFINES
     APP_NAME="${APP_NAME}"
+    APP_AANDERAA_CURRENT_METER
     # Add network stress test functions
     STRESS_TEST_ENABLE
 )

src/apps/rs232_expander_apps/rs232_expander_apps_common/FreeRTOSConfig.h

@@ -63,7 +63,11 @@ extern "C" {
 #define configUSE_PREEMPTION                     1
 #define configSUPPORT_STATIC_ALLOCATION          1
 #define configSUPPORT_DYNAMIC_ALLOCATION         1
+#ifdef APP_AANDERAA_CURRENT_METER
+#define configUSE_IDLE_HOOK                      0
+#else // APP_AANDERAA_CURRENT_METER
 #define configUSE_IDLE_HOOK                      1
+#endif // APP_AANDERAA_CURRENT_METER
 #define configUSE_TICK_HOOK                      0
 #define configCPU_CLOCK_HZ                       ( SystemCoreClock )
 #define configTICK_RATE_HZ                       ((TickType_t)1000)

src/apps/rs232_expander_apps/rs232_expander_apps_common/app_main.cpp

@@ -268,6 +268,9 @@ static void defaultTask(void *parameters) {
   // platform boot before starting the watchdog task
   memfault_platform_boot();
 
+  #ifdef APP_AANDERAA_CURRENT_METER
+  startIWDGTask();
+  #endif // APP_AANDERAA_CURRENT_METER
   startSerial();
 
   startSerialConsole(&usbCLI);

src/apps/rs232_expander_apps/rs232_expander_apps_common/task_priorities.h

@@ -29,3 +29,4 @@
 #define CLI_TASK_PRIORITY 1
 #define DEFAULT_TASK_PRIORITY 1
 
+#define IWDG_TASK_PRIORITY 0

src/lib/common/lpm_u5.c

@@ -152,10 +152,18 @@ void lpmPreSleepProcessing() {
 }
 
 void lpmPostSleepProcessing() {
+  //
+  // A bug was found with the Aanderaa Current Meter RS232 Mote application with this
+  // implementation of the watchdog. So for now while we figure out how to workaround it
+  // we will go back to using the old watchdog for the Aanderaa Current Meter RS232 app.
+  // See watchdog.c for more details.
+  //
+  #ifndef APP_AANDERAA_CURRENT_METER
   // reference xMaximumSuppressedTicks, the maximum amount of time we can sleep
   // is 1998 ticks (or ms, ref configTICK_RATE_HZ). Feed the watchdog here
   // before moving onto next tasks
   watchdogFeed();
+  #endif // APP_AANDERAA_CURRENT_METER
   if (SCB->SCR & SCB_SCR_SLEEPDEEP_Msk)
    {
       //      We may have been in deep sleep.  If we were, the RCC cleared several enable bits in the CR, and

src/lib/common/watchdog.c

@@ -6,8 +6,36 @@
 #include "iwdg.h"
 #include "task_priorities.h"
 
+// If you want to use the memfault watchdog, uncomment the following include,
+// enable the LPTIM2 clock, and uncomment the memfault_software_watchdog_enable()
+// call in startIWDGTask() and the memfault_software_watchdog_feed() call in watchdogFeed()
+// #include "memfault/ports/watchdog.h"
+
 void watchdogFeed() {
   LL_IWDG_ReloadCounter(IWDG);
+  // memfault_software_watchdog_feed();
+}
+
+/***************************************************************************************
+ *
+ * Potential Watchdog issue relating to STM32u575 Errata 2.2.26
+ *
+ * We have observed that the Aanderaa Current Meter RS232 application has been
+ * unexpectedly resetting during some of our testing. Through testing and git bisecting
+ * we were able to determine that the commit that changed the watchdog from PR#316
+ * was the commit that introduced the issue. Interestingly with the watchdog changes
+ * this vApplicationIdleHook gets called before we enter Stop mode. Errata 2.2.26 states
+ * that there are certain conditions that if met upon entering sleep would result in
+ * the processor being stuck in stop mode with a system reset being the only recovery
+ * method. So this errata, along with other theories are being investigated to root
+ * cause the unexpected resets.
+ *
+ * While we are doing that we are going to go back to using the old watchdog for the
+ * Current Meter Aanderaa RS232 application.
+ *
+***************************************************************************************/
+void vApplicationIdleHook(void) {
+    watchdogFeed();
 }
 
 //
@@ -25,10 +53,33 @@ void watchdogFeed() {
 //        periodically and the watchdog is only refreshed when several
 //        conditions are met.
 //
+#ifdef APP_AANDERAA_CURRENT_METER
+static void iWDGTask( void *parameters );
 
-void vApplicationIdleHook(void) {
+void startIWDGTask() {
+  // memfault_software_watchdog_enable();
+  BaseType_t rval;
+  rval = xTaskCreate(
+              iWDGTask,
+              "IWDG",
+              configMINIMAL_STACK_SIZE,
+              NULL,
+              IWDG_TASK_PRIORITY,
+              NULL);
+
+  configASSERT(rval == pdTRUE);
+}
+
+static void iWDGTask( void *parameters ) {
+  // Don't warn about unused parameters
+  (void) parameters;
+
+  for(;;) {
     watchdogFeed();
+    vTaskDelay(2 * 1000);
+  }
 }
+#endif // APP_AANDERAA_CURRENT_METER
 
 void IWDG_IRQHandler(void) {
   LL_IWDG_EnableWriteAccess(IWDG);

src/lib/common/watchdog.h

@@ -4,6 +4,7 @@
 extern "C" {
 #endif
 
+void startIWDGTask();
 void watchdogFeed();
 
 #ifdef __cplusplus