UCM-iMX7: Linux: Manual Installation: SD
Instoduction
This article provides an introduction on how to install the Linux kernel and the example root filesystem image for the CompuLab UCM-iMX7 System-on-Module / Computer-on-Module onto removable micro SD card using Linux host machine.
Preparation steps
- Obtain a Linux PC workstation with a USB port.
- Download the Linux package for UCM-iMX7 from CompuLab website. Unzip the package to a directory on your host workstation. The following article uses /path/to/ucm-imx7-linux/ template for this location. Please use the real path to the Linux package instead.
- All image files mentioned below can be found in the images subdirectory.
- Obtain an SD card. Any commercially available SD card of 1GB (or larger) may be used.
- Obtain a USB Card reader with SD card slot.
Install Linux Images
- Plug the USB SD Card reader to a host Linux PC. Insert the SD Card into the USB Card reader. The following discussion assumes the device name of the SD card on your Linux PC is /dev/sdc Please use the actual device name instead.
- Depending on the desktop system setup, following steps might require super user privileges.
- Unmount all SD card partitions:
umount -l /dev/sdc*
- Clean up the on the SD card:
dd if=/dev/zero of=/dev/sdc bs=1M count=1 hdparm -z /dev/sdc
- Create two partitions for the Linux kernel (EXT2 100M) and root file system (EXT4 the rest of the disk) on the SD card:
echo -e "n\np\n1\n\n+100M\nn\np\n2\n\n\nw\neof\n" | fdisk /dev/sdc
- Format the first partition with EXT2 file system:
mkfs.ext2 -L boot /dev/sdc1
- Format the second partition with EXT4 file system:
mkfs.ext4 -L rootfs /dev/sdc2
- Mount both partitions:
mkdir -p /media/boot && mount /dev/sdc1 /media/boot mkdir -p /media/rootfs && mount /dev/sdc2 /media/rootfs
- Copy zImage and imx7d-*imx7.dtb to the first (EXT2) partition:
cp /path/to/ucm-imx7-linux/images/zImage /path/to/ucm-imx7-linux/images/imx7d-*.dtb /media/boot && sync
- Extract the content of rootfs.tar.bz2 onto the second partition:
tar --numeric-owner -xpf /path/to/ucm-imx7-linux/images/rootfs.tar.bz2 -C /media/rootfs && sync
- Unmount both partitions:
umount /media/boot umount /media/rootfs
- Eject the SD card
eject /dev/sdc
- Remove the SD card from the SD card reader
After Installation
- Plug the SD card to the micro SD socket (P8) on the SBC-UCM-iMX7.
- The default U-Boot environment configuration can boot from am external micro SD card if proper images are found on it.
- Alternatively, you can use the following U-Boot commands to configure removable micro SD card as the main storage for both Linux kernel and root filesystem images manually:
UCM-iMX7 # env default -a
UCM-iMX7 # setenv bootdelay 3
UCM-iMX7 # setenv image zImage
UCM-iMX7 # setenv loadaddr 0x80800000
UCM-iMX7 # setenv fdt_file imx7d-sbc-ucm-imx7.dtb
UCM-iMX7 # setenv fdt_addr 0x83000000
UCM-iMX7 # setenv mmcroot "/dev/mmcblk0p2 rootwait rw"
UCM-iMX7 # setenv loadimage 'load mmc 0:1 ${loadaddr} ${image}'
UCM-iMX7 # setenv loadfdt 'load mmc 0:1 ${fdt_addr} ${fdt_file}'
UCM-iMX7 # setenv bootargs "console=ttymxc0,115200 root=${mmcroot}"
UCM-iMX7 # setenv bootcmd 'run loadimage; run loadfdt; bootz ${loadaddr} - ${fdt_addr}'
- To save this configuration:
UCM-iMX7 # saveenv
- To boot Linux type:
UCM-iMX7 # boot
