For information on 5V tolerance, please refer to the following document.

・IGLOO2
Documentation > User Guides Tab > UG0445: SmartFusion2 SoC FPGA and IGLOO2 FPGA Fabric User Guide
"6.13 5 V Input Tolerance and Output Driving Compatibility (only MSIO)"
　https://www.microchip.com/en-us/products/fpgas-and-plds/fpgas/igloo-2-fpgas#Documentation

・ProASIC3
   Documentation > User Guides tab >ProASIC3 FPGA Fabric User's Guide
"5V Input and Output Tolerance"
　https://www.microchip.com/en-us/products/fpgas-and-plds/fpgas/proasic-3-fpgas

For input, please follow the documentation by adding resistors or Zener diodes, etc.
Please also check the datasheet to see if the output meets the specifications of the connected device.

・IGLOO2
Documentation > Data Sheets tab > IGLOO 2 FPGA and SmartFusion 2 SoC FPGA Datasheet
"3.5.6.2 3.3V LVCMOS/LVTTL"
   https://www.microchip.com/en-us/products/fpgas-and-plds/fpgas/igloo-2-fpgas#Documentation

・ProASIC3
Documentation > Data Sheets Tab > ProASIC 3 Flash Family FPGAs with Optional Soft ARM
“2.3.2.1 Summary of I/O DC Input and Output Levels – Default I/O Software Settings”
　https://www.microchip.com/en-us/products/fpgas-and-plds/fpgas/proasic-3-fpgas