TFTP download kernel, NFS mount file system

TFTP Download function ：

1、 First, build tftp The server ： Under the virtual machine Ubuntu20

sudo apt-get install tftp-hpa tftpd-hpa
sudo apt-get install xinetd

mkdir -p /home/ckl/my_board/tftp

sudo chmod 777 /home/ckl/my_board/tftp

2、 To configure tftp：

New file /etc/xinetd.d/tftp

server tftp
{
		socket_type = dgram
		protocol = udp
		wait = yes
		user = root
		server = /usr/sbin/in.tftpd
		server_args = -s /home/ckl/my_board/tftp
		disable = no
		per_source = 11
		cps = 100 2
		flags = IPv4
}

Modify file ：/etc/default/tftpd-hpa

# /etc/default/tftpd-hpa

TFTP_USERNAME="tftp"
TFTP_DIRECTORY="/home/ckl/my_board/tftp"
TFTP_ADDRESS=":69"
TFTP_OPTIONS="-l -c -s"

3、 take Image and dtb Put it in tftp Under the table of contents

mount ：

1、 Format a SD card （fat32 Format ）

2、 Only the modified atom is burned uboot

sudo dd if=./u-boot.imx of=/dev/sdc bs=1024 seek=1

 3、 Set network related parameters ：

==> setenv ipaddr 192.168.1.100
==> setenv ethaddr 0:0c:29:c6:ff:c9
==> setenv gatewayip 192.168.1.1
==> setenv netmask 255.255.255.0
==> setenv serverip 192.168.1.99

【 Premise ： It's set up 】： Reference resources ：uboot Next use nfs Download Online kernel

4、 a key ：

1、 Set up bootarges( Set up nfs Mount file system )

setenv bootargs 'console=ttymxc0,115200 root=/dev/nfs nfsroot=192.168.1.99:/home/ckl/my_board/nfs/rootfs,proto=tcp nfsvers=4 rw ip=192.168.1.100:192.168.1.99:192.168.1.1:255.255.255.0:ckl:eth0:off'

$ root=/dev/nfs nfsroot=[<server-ip>:]<root-dir>[,<nfs-options>] ip=<client-ip>:<server-ip>:<gwip>:<netmask>:<hostname>:<device>:<autoconf>:<dns0-ip>:<dns1-ip>
 

<server-ip>： The server IP Address , That is, the host where the root file system is stored IP Address
<root-dir>： Storage path of root file system
<nfs-options>： NFS Other optional options for , Generally not set
<client-ip>： client IP Address , That is, our development board IP Address
<server-ip>： The server IP Address , ditto

<gw-ip>： default gateway
<netmask>： Subnet mask , It's usually 255.255.255.0

<hostname>： The name of the client , This value can be left blank

<device>： Device name , That is, the network card name , The use of atomic alpha use ENET2, Network card name is eth0

<autoconf>： Automatic configuration , Generally not used , So set to off
<dns0-ip>： DNS0 The server IP Address , Don't use
<dns1-ip>： DNS1 The server IP Address , Don't use

therefore ：root=/dev/nfs nfsroot=192.168.1.99:/home/ckl/my_board/nfs/rootfs,proto=tcp rw ip=192.168.1.100:192.168.1.99:192.168.1.1:255.255.255.0:ckl:eth0:off

proto=tcp” Said the use of TCP agreement ,“rw” Express nfs The mounted root file system is readable and writable

Baidu ：nfs The mount is incompatible , So will bootargs Change to specify NFSv4

2、 Set up bootcmd

setenv bootcmd 'tftp 80800000 zImage;tftp 83000000 standerd.dtb;bootz 80800000 - 83000000'

​=> saveenv

=> reset