VHDL timer

hie i am a newbie ..

i managed to create a program that read input from the PIR sensor from the gpio and when sensor sense movement it will turn on and LED on the DE2 board. how can i write the timer that stays on for 5 to 10 minutes.

here i attcehed my code...

library IEEE;

use ieee.std_logic_1164.all;

use IEEE.numeric_std.all;

entity ltestinggpiowithdelay is

port( GPIO_0 : in std_logic_vector(2 downto 0);

q : out std_logic_vector(2 downto 0));

end ltestinggpiowithdelay ;

architecture bufferwithGpio_arc of ltestinggpiowithdelay is

begin

process(GPIO_0)

begin

if (GPIO_0(0)='1') then q<=GPIO_0(2 downto 0);

else q<= "000";

end if;

end process;

end bufferwithGpio_arc;