[G4] Persistent object support

src/main/drivers/persistent.c

@@ -51,18 +51,33 @@ void persistentObjectWrite(persistentObjectId_e id, uint32_t value)
 
 void persistentObjectRTCEnable(void)
 {
+#if !defined(STM32G4)
+    // G4 library V1.0.0 __HAL_RTC_WRITEPROTECTION_ENABLE/DISABLE macro does not use handle parameter
     RTC_HandleTypeDef rtcHandle = { .Instance = RTC };
+#endif
 
 #if !defined(STM32H7)
     __HAL_RCC_PWR_CLK_ENABLE(); // Enable Access to PWR
 #endif
+
     HAL_PWR_EnableBkUpAccess(); // Disable backup domain protection
 
+#if defined(STM32G4)
+    /* Enable RTC APB clock  */
+    __HAL_RCC_RTCAPB_CLK_ENABLE();
+
+    /* Peripheral clock enable */
+    __HAL_RCC_RTC_ENABLE();
+
+#else // !STM32G4, F7 and H7 case
+
 #if defined(__HAL_RCC_RTC_CLK_ENABLE)
     // For those MCUs with RTCAPBEN bit in RCC clock enable register, turn it on.
     __HAL_RCC_RTC_CLK_ENABLE(); // Enable RTC module
 #endif
 
+#endif // STM32G4
+
     // We don't need a clock source for RTC itself. Skip it.
 
     __HAL_RTC_WRITEPROTECTION_ENABLE(&rtcHandle);  // Reset sequence

src/main/drivers/system.h

@@ -66,7 +66,7 @@ bool isMPUSoftReset(void);
 void cycleCounterInit(void);
 uint32_t clockCyclesToMicros(uint32_t clockCycles);
 uint32_t getCycleCounter(void);
-#if defined(STM32H7)
+#if defined(STM32H7) || defined(STM32G4)
 void systemCheckResetReason(void);
 #endif