Https://www.sammobile.com/firmwares/gt-s5380/GT-S5380/
Cred ca asta vrei tu. Descarci asta, descarci odin, intri in download mode, conectezi la pc, deschizi odin, bagi fisierele in odin si astepti sa se instaleze firmware-ul.
Am gasit si asta, poate te referiai la asta: https://www.youtube.com/watch?v=Mfs8A9kTLjc