CL-SOM-iMX7: Linux: Manual Installation: Source: Network
Contents
Introduction
This article provides an introduction on how to install the Linux kernel and the example root filesystem image on the CompuLab CL-SOM-iMX7 System-on-Module / Computer-on-Module eMMC internal storage device using network interface as the installation source.
Preparation steps
- Obtain a PC workstation with a serial communication port.
- For networked installation you need to install a TFTP server on the host PC. For Windows machines we recommend TFTPD32 included in the Linux package for CL-SOM-iMX7 (link below).
- Download the CL-SOM-iMX7 BSP binary from CompuLab website. Unzip the package to a directory on your host workstation.
- All image files mentioned below can be found in the install sub-directory.
- Connect the host PC to the SBC-iMX7 USB console connector (P7) with the USB cable supplied in the evaluation kit.
Preparing installation media
- Connect the CL-SOM-iMX7 Ethernet port (connector P21 on the SBC-iMX7) to your local network using the standard Cat 5 LAN cable.
- Make sure the dedicated TFTP server as well as NFS server (may be the same machine) are connected to the local network too.
- Put kernel.img, ramdisk.img from the unzipped BSP binary package to a location accessible by the TFTP server:
- - On Windows machine: copy files to the same folder and point the TFTP server to that folder
- - On Linux machine: copy files to the TFTP server root directory, usually /tftpboot or /tftproot.
Boot into the installation environment (ramdisk)
- Start terminal emulation software on your PC with the following serial port settings:
Baud Rate Data Bits Stop Bits Parity Flow Control 115200 8 1 none none
- Make sure no removable media (e.g.USB storage, micro SD) is plugged.
- Turn on the device. Press a key to prevent a possible autoboot and get into the U-Boot command prompt.
If the boot settings of your device are different than the default, you may need to press and hold Ctrl-C while turning the device on, in order to get command prompt. |
- You can use U-Boot dhcp command to obtain an IP address or manually set ipaddr environment variable:
dhcp
- or
setenv ipaddr <device ip address>
- Set the serverip environment variable:
setenv serverip <tftp server ip address>
- Use the following U-Boot commands to boot Linux:
setenv fdtfile imx7d-sbc-imx7.dtb
setenv loadaddr 0x80800000 setenv fdtaddr 0x83000000 setenv ramdisk_addr 0x82000000 setenv bootargs 'root=/dev/ram0 rw ramdisk_size=16384 console=ttymxc0,115200 ip=dhcp vram=16M' tftpboot ${loadaddr} kernel.img && tftpboot ${fdtaddr} ${fdtfile} && tftpboot ${ramdisk_addr} ramdisk.img bootz ${loadaddr} ${ramdisk_addr} ${fdtaddr}
Install Linux Images
The next step is installing the kernel and Debian Linux images.
Mount an NFS drive
- Copy the rootfs.tar.bz2, imx7d-*.dtb and the zImage from the unzipped BSP binary package to a directory exported through NFS.
- Obtain an IP address for the device:
- Using DHCP:
root@cl-ramdisk:~# ifup eth0
- If you do not have a DHCP server, you can set a static IP address using ifconfig:
root@cl-ramdisk:~# ifconfig eth0 <ip address>
- Using DHCP:
- Mount the NFS share:
root@cl-ramdisk:~# mount -o nolock <host ip>:/path/to/nfs/share /mnt/install
Install Images on eMMC
- Unmount all eMMC partitions:
root@cl-ramdisk:~# umount -l /dev/mmcblk2p*
- Clean up the on the eMMC flash:
root@cl-ramdisk:~# dd if=/dev/zero of=/dev/mmcblk2 bs=1M count=1 root@cl-ramdisk:~# hdparm -z /dev/mmcblk2
- Create two partitions for the Linux kernel (EXT2 100M) and root file system (EXT4 the rest of the disk) on the eMMC flash:
root@cl-ramdisk:~# echo -e "n\np\n1\n\n+100M\nn\np\n2\n\n\nw\neof\n" | fdisk /dev/mmcblk2
- Format the first partition with EXT2 file system:
root@cl-ramdisk:~# mkfs.ext2 -L boot /dev/mmcblk2p1
- Format the second partition with EXT4 file system:
root@cl-ramdisk:~# mkfs.ext4 -L rootfs /dev/mmcblk2p2
- Mount both partitions:
root@cl-ramdisk:~# mkdir -p /media/boot && mount /dev/mmcblk2p1 /media/boot root@cl-ramdisk:~# mkdir -p /media/rootfs && mount /dev/mmcblk2p2 /media/rootfs
- Copy zImage and imx7d-*imx7.dtb to the first (EXT2) partition:
root@cl-ramdisk:~# cp /mnt/install/zImage /mnt/install/imx7d-*.dtb /media/boot && sync
- Extract the content of rootfs.tar.bz2 onto the second partition:
root@cl-ramdisk:~# tar --numeric-owner -xpf /mnt/install/rootfs.tar.bz2 -C /media/rootfs && sync
- Unmount both partitions:
root@cl-ramdisk:~# umount /dev/mmcblk2p1 root@cl-ramdisk:~# umount /dev/mmcblk2p2
After Installation
- Reboot the device
- Press a key to prevent a possible autoboot and get into the U-Boot command prompt.
- Use the following U-Boot commands to configure eMMC as the main storage for both Linux kernel and root filesystem images:
env default -a setenv bootdelay 3 setenv kernel zImage setenv loadaddr 0x80800000 setenv fdtfile imx7d-sbc-imx7.dtb setenv fdtaddr 0x83000000 setenv mmcroot "/dev/mmcblk2p2 rootwait rw" setenv loadimage 'load mmc 1:1 ${loadaddr} ${kernel}' setenv loadfdt 'load mmc 1:1 ${fdtaddr} ${fdtfile}' setenv bootargs "console=ttymxc0,115200 root=${mmcroot}" setenv bootcmd 'run loadimage; run loadfdt; bootz ${loadaddr} - ${fdtaddr}'
- To save this configuration:
saveenv
- To boot Linux type:
run bootcmd