Generic FF procedure

generic_ff_pack.vhd

library ieee;
  use ieee.std_logic_1164.all;

package generic_ff_pack is
  procedure FF
    generic (
      type T)
    parameter (
      signal   q         : out   T;
      constant d         : in    T;
      constant INIT_VAL  : in    T;
      constant rst       : in    std_logic;
      signal   clk       : in    std_logic;
      constant en        : in    std_logic := '1');
end package generic_ff_pack;

package body generic_ff_pack is
  procedure FF
    generic (
      type T)
    parameter (
      signal   q         : out T;
      constant d         : in  T;
      constant INIT_VAL  : in  T;
      constant rst       : in  std_logic;
      signal   clk       : in  std_logic;
      constant en        : in  std_logic := '1') is
  begin
    if (rising_edge(clk)) then
      if (rst /= '0') then
        q <= INIT_VAL;
      elsif (en = '1') then
        q <= d;
      end if;
    end if;
  end procedure FF;
end package body;

generic_ff_tb.vhd

library ieee;
  use ieee.std_logic_1164.all;
library generic_ff_lib;
  use generic_ff_lib.generic_ff_pack.all;

entity generic_ff_tb is
  port (
    clkIn       : in    std_logic;
    rstIn       : in    std_logic;
    enIn        : in    std_logic;
    valIn       : in    std_logic_vector(7 downto 0);
    valOut      :   out std_logic_vector(7 downto 0));
end entity generic_ff_tb;

architecture behav of generic_ff_tb is
  procedure ff_byte is new FF generic map (T => std_logic_vector(7 downto 0));
  constant INIT_VAL : std_logic_vector(7 downto 0) := (others=>'0');
begin
  ff_byte(valOut, valIn, INIT_VAL, rstIn, clkIn, enIn, '1');
end architecture behav;