As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT 612 - PHX - RTF - AVIONICS SMOKE DISPLAYED ON UPPER ECAM AFTER TAKEOFF. CREW DECLARED AN EMERGENCY AND RETURNED TO PHX LANDING WITHOUT INCIDENT. MAINTENANCE REMOVED AND REPLACED THE AVIONICS EQUIPMENT VENTILATION COMPUTER 10HQ IAW AIRBUS MAINTENANCE MANUAL 21-26-34.