The datasheet of LS1020A says, that pins IFC_A16 - IFC_A20 can be pulled up or tristate (mark 5). Just a requirement - no pull-down.
The application note AN4878 says:
For LS1020A device configuration, IFC_A16 and IFC_A17 must be pulled up
during power-on reset.
Where is the truth? Can these pins be floating or not?