clock divider

You better use a modulo adder e.g. add 83 modulo 125 and generate clk en at overflow.

You may try this code, I haven't tested it but I will appreciate if you do and let me know the outcome:

variable count : integer range 0 to 124 := 0;
process
begin
wait until clk50mhz = '1';
if count < 125 then
     count := count + 83;
     clken <= '0';
else
     count := count - 125;
     clken <= '1';
end if;
end process;