MAGIC value for powerReason should be stored in RTC backup on Horus (#7096)

- Allows the radio main application to start correctly when coming from an app in RAM
- Refactoring of the `UNEXPECTED_SHUTDOWN()` process
- Saves the RTC battery as BACKUP RAM is not needed on normal shutdown
- On PWR OFF on an ALERT, the radio won't show the next alert before shutting down
- Bootloader flashable through the SD Manager

radio/src/storage/eeprom_rlc.cpp

@@ -729,7 +729,7 @@ void RlcFile::nextRlcWriteStep()
 void RlcFile::flush()
 {
   while (!eepromIsTransferComplete())
-    wdt_reset();
+    WDG_RESET();
 
   ENABLE_SYNC_WRITE(true);
 

radio/src/storage/rtc_backup.h

@@ -0,0 +1,33 @@
+/*
+ * Copyright (C) OpenTX
+ *
+ * Based on code named
+ *   th9x - http://code.google.com/p/th9x
+ *   er9x - http://code.google.com/p/er9x
+ *   gruvin9x - http://code.google.com/p/gruvin9x
+ *
+ * License GPLv2: http://www.gnu.org/licenses/gpl-2.0.html
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef _RAM_BACKUP_H_
+#define _RAM_BACKUP_H_
+
+#include "definitions.h"
+
+PACK(struct RamBackup {
+  uint16_t size;
+  uint8_t data[4094];
+});
+
+extern RamBackup * ramBackup;
+
+#endif // _RAM_BACKUP_H_

radio/src/storage/sdcard_raw.h

@@ -38,11 +38,4 @@ const char * createModel();
 const char * loadRadioSettings(const char * path);
 const char * loadRadioSettings();
 
-PACK(struct RamBackup {
-  uint16_t size;
-  uint8_t data[4094];
-});
-
-extern RamBackup * ramBackup;
-
 #endif // _SDCARD_RAW_H_

radio/src/storage/storage.h

@@ -23,7 +23,7 @@
 
 #if defined(SIMU)
   #define WRITE_DELAY_10MS 100
-#elif defined(RAMBACKUP)
+#elif defined(RTC_BACKUP_RAM)
   #define WRITE_DELAY_10MS 1500 /* 15s */
 #elif defined(PCBTARANIS)
   #define WRITE_DELAY_10MS 500
@@ -37,10 +37,11 @@ extern uint8_t   storageDirtyMsk;
 extern tmr10ms_t storageDirtyTime10ms;
 #define TIME_TO_WRITE()                (storageDirtyMsk && (tmr10ms_t)(get_tmr10ms() - storageDirtyTime10ms) >= (tmr10ms_t)WRITE_DELAY_10MS)
 
-#if defined(RAMBACKUP)
+#if defined(RTC_BACKUP_RAM)
+#include "storage/rtc_backup.h"
 extern uint8_t   rambackupDirtyMsk;
 extern tmr10ms_t rambackupDirtyTime10ms;
-#define TIME_TO_RAMBACKUP()            (rambackupDirtyMsk && (tmr10ms_t)(get_tmr10ms() - rambackupDirtyTime10ms) >= (tmr10ms_t)100)
+#define TIME_TO_BACKUP_RAM()            (rambackupDirtyMsk && (tmr10ms_t)(get_tmr10ms() - rambackupDirtyTime10ms) >= (tmr10ms_t)100)
 #endif
 
 void storageEraseAll(bool warn);
@@ -64,7 +65,7 @@ void checkExternalAntenna();
 #include "sdcard_raw.h"
 #endif
 
-#if defined(RAMBACKUP)
+#if defined(RTC_BACKUP_RAM)
 void rambackupWrite();
 bool rambackupRestore();
 unsigned int compress(uint8_t * dst, unsigned int dstsize, const uint8_t * src, unsigned int len);

radio/src/storage/storage_common.cpp

@@ -24,7 +24,7 @@
 uint8_t   storageDirtyMsk;
 tmr10ms_t storageDirtyTime10ms;
 
-#if defined(RAMBACKUP)
+#if defined(RTC_BACKUP_RAM)
 uint8_t   rambackupDirtyMsk;
 tmr10ms_t rambackupDirtyTime10ms;
 #endif
@@ -34,7 +34,7 @@ void storageDirty(uint8_t msk)
   storageDirtyMsk |= msk;
   storageDirtyTime10ms = get_tmr10ms();
 
-#if defined(RAMBACKUP)
+#if defined(RTC_BACKUP_RAM)
   rambackupDirtyMsk = storageDirtyMsk;
   rambackupDirtyTime10ms = storageDirtyTime10ms;
 #endif