No need to use ip/ and no need to use *_top.vhd.

libraries/technology/ip_arria10/phy_10gbase_r/README.txt

libraries/technology/ip_arria10/phy_10gbase_r/compile_ip.tcl

libraries/technology/ip_arria10/phy_10gbase_r/generate_ip.sh

libraries/technology/ip_arria10/phy_10gbase_r/hdllib.cfg

libraries/technology/ip_arria10/phy_10gbase_r/ip/hdllib.cfg

...gy/ip_arria10/phy_10gbase_r/ip_arria10_phy_10gbase_r.qsys

...ip_arria10/phy_10gbase_r/ip_arria10_phy_10gbase_r_top.vhd