＜エラーメッセージ＞
Error (14566): Could not place periphery component(s) due to conflicts with existing constraints ( Transmitter channel(s))
Error (175020): Illegal constraint of Transmitter channel that is part of Arria V Transceiver Native PHY xxxxxxxx to the region (x, x) to (x, x): no valid locations in region
Error (16234): No legal location could be found out of 1 considered location(s). Reasons why each location could not be used are summarized below:
Error (175005): Could not find a location with: xxxxxx (1 location affected)

Category: Transceiver
Tools: Quartus® Prime / Quartus® II
Device: Arria® V


The cause of the error is that the IP setting is set to "PMA Direct".
Arria V devices do not support PMA Direct.

Reference information
https://www.altera.com/en_US/pdfs/literature/ug/xcvr_user_guide.pdf
(Search for Arria V Transceiver Native PHY, Standard PCS, PMA Direct, etc.)