install tftpd

apt-get install tftpd tftp xinetd

cd /etc/xinetd.d/
vi tftp 
service tftp
{
socket_type = dgram
protocol = udp
wait = yes
user = root
server = /usr/sbin/in.tftpd
server_args = -s /tftpboot
disable = no
per_source = 11
cps = 100 2
flags = IPv4
}