Need some help with PHP

please read the code below,
<form action="login.php?mode=login" method="post" >
Username: <input type="text" name="username"><br />
Password: <input type="password" name="password"><br />
<input type="submit" value="login" name="login">
</form>
my requirement is display user name and password in the top of “login.php” , can someone please provide PHP code
