In reply to rgarcia07:
You can also do
covergroup cg @(posedge clk) {
enable_cp: coverpoint enable;
bins v = {1};
}
one_hot_mode_cp: coverpoint mode {
bins one_hot[N] = one_hot_mode_cp with ($onehot(item));
}
cross enable_cp, one_hot_mode_cp;
endgroup