IOT-GATE-iMX7 and SBC-IOT-iMX7: Linux: Manual Installation: Micro SD

Instoduction

This article provides an introduction on how to install the Linux kernel and the example root filesystem image for the IOT-GATE-iMX7 Internet of Things Gateway or CompuLab SBC-IOT-iMX7 Internet of Things Single Board Computer onto removable micro SD card using Linux host machine.

Preparation steps

• Obtain a Linux PC workstation with a USB port.
• Download the BSP binary package for IOT-GATE-iMX7 and SBC-IOT-iMX7 from CompuLab website. Use either IOT-GATE-iMX7 or SBC-IOT-iMX7 product web page for downloading. Unzip the package to a directory on your host workstation. The following discussion uses /path/to/cl-som-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 install subdirectory.
• Obtain a micro SD card. Any commercially available micro SD card of 1GB (or larger) may be used.
• Obtain a USB Card reader with micro SD card slot or use microSD-to-SD adapter.

Install Linux Images

• Plug the USB SD Card reader to a host Linux PC. Insert the micro SD Card into the USB Card reader. The following discussion assumes the device name of the micro 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/cl-som-imx7-linux/images/zImage /path/to/cl-som-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/cl-som-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 installation media (micro MMC/SD card) to the microSD socket marked uSD on IOT-GATE-iMX7 front panel (slot P18 on the SBC-iMX7).
• Use the following U-Boot commands to configure removable micro SD card 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-iot-imx7.dtb
setenv fdtaddr 0x83000000
setenv mmcroot "/dev/mmcblk0p2 rootwait rw"
setenv loadimage 'load mmc 0:1 ${loadaddr} ${kernel}'
setenv loadfdt 'load mmc 0:1 ${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