backup ram: store MMC card status in backup register

Author: dron0gus

firmware/hw_layer/backup_ram.h

@@ -26,6 +26,12 @@ enum class backup_ram_e {
 	 */
 	IgnCounter,
 
+	/**
+	 * MMC card status
+	 * 32 bits value, see mmc_card.c for details
+	 */
+	MccStatus,
+
 	/* The number of stored backup variables */
 	BACKUP_RAM_NUM,
 };

firmware/hw_layer/ports/stm32/backup_ram.cpp

@@ -13,6 +13,8 @@ uint32_t backupRamLoad(backup_ram_e idx) {
 		return RTCD1.rtc->BKP0R & 0xffff;
 	case backup_ram_e::IgnCounter:
 		return (RTCD1.rtc->BKP0R >> 16) & 0xff;
+	case backup_ram_e::MccStatus:
+		return RTCD1.rtc->BKP1R;
 	default:
 		criticalError("Invalid backup ram idx %d", (int)idx);
 		return 0;
@@ -31,6 +33,9 @@ void backupRamSave(backup_ram_e idx, uint32_t value) {
 	case backup_ram_e::IgnCounter:
 		RTCD1.rtc->BKP0R = (RTCD1.rtc->BKP0R & ~0x00ff0000) | ((value & 0xff) << 16);
 		break;
+	case backup_ram_e::MccStatus:
+		RTCD1.rtc->BKP1R = value;
+		break;
 	default:
 		criticalError("Invalid backup ram idx %d, value %lx", (int)idx, value);
 		break;