In reply to vybhava:
If you want to share signals in one interface with another interface, make them ports of the interface. You need to use wires if you want to have bidirectional signals.
interface mem_ctrl_if (
input logic Reset, // shared signals
input logic Clock
);
logic [9:0] Addr; // per interface instance signals
wire [7:0] Data;
logic RWn;
endinterface
interface mem_if(
input logic reset,
input logic clock
);
logic enable;
logic [7:0] addr;
wire [7:0] data;
logic rwn;
endinterface
Then when you instantiate them
mem_if mem0if(ctrl_if.Reset,ctrl_if.Clock);