Hi All,
I was going to post my solution soon but was too busy. So,
Yes I was able to solve the issue. The problem was that since i was only using the Dq_dqs2_bidir IP to write data out so i was not using the Read_data_out lines coming to the core from dq_dqs2 IP.
So i added the following code to use the read_data lines and the error "RDEN not legally connected or configured" was not occuring anymore.
process(core_clk)
begin
if(rising_edge(core_clk) ) then
read_datacore <= read_data_out;
end if;
end process;
Hope it solves your problem too :)
Best regards
waqas