Frequently Asked Questions for i.MX6 Linux

Compiling

U-boot

Please refer to the following sections for details

• Getting Started / Build Instructions / To build u-boot _{(LBV3) (LBV5) (LBV6)}

• Customization / Building & updating u-boot manually _{(LBV3) (LBV5) (LBV6)}

Kernel

Please refer to the following sections for details

• Getting Started / Build Instructions / To build linux kernel _{(LBV3) (LBV5) (LBV6)}
• Customization / Building & updating kernel/modules/dtb manually _{(LBV3) (LBV5) (LBV6)}

Boot Logo

Kernel

In Yocto Project, it is called "boot splashscreen", please refer to the each BSP's corresponding official Yocto website (list as below) for details

• Yocto Project Reference Manual / Other Tips. _{(LBV3) (LBV5) (LBV6)}

SDcard image

To build from prebuilt image, please refer to the following sections for details.

• Getting Started / Introducing BSP / Prebuilt image _{(LBV3) (LBV5) (LBV6)}

To build from BSP, please refer to the following sections for details.

• Getting Started / Build Instructions / To build sdcard image _{(LBV3) (LBV5) (LBV6)}

How To Stress Test On a Linux

Perform the command as below:

stress -c 4 -i 4  -d 1 --hdd-bytes 512

How To create one LIV disk image of SD card

The LIV disk image of SD card is used to boot target device up and to install the entire system to on-baord eMMC.

• Prerequisites
  1. one free loop device with partition support
  2. prewritten script tarball, mk_inand.tar.gz.
  3. the original sdcard _{(LBV3) (LBV5) (LBV6)}
  4. 3700MB more available disk space

E.g.

$ export LODEV=$(sudo losetup -f)
$ export MKINAND=mk_inand.tar.gz
$ export SDCARD=fsl-image-qt5-imx6qrsb4410a1.sdcard
$ export LIV=4410A1LIV6000.img
$ cp ${SDCARD} ${LIV}
$ dd if=/dev/zero of=${LIV} bs=1M seek=3700 count=0

• using the following commands to create one

$ sudo losetup ${LODEV} ${LIV}
$ cat << EOF | sudo fdisk -u ${LODEV}
d
2
n
p
2
24576

w
EOF
$ sudo e2fsck -f ${LODEV}p2
$ sudo resize2fs ${LODEV}p2
$ mkdir -p ~/mnt/p2
$ sudo mount /dev/loop0p2 ~/mnt/p2
$ sudo mkdir ~/mnt/p2/{mk_inand,image}
$ sudo cp ${SDCARD} ~/mnt/p2/image/
$ cat << 'MKSD_EOF' > ${MKSD}
#!/bin/bash

echo -e "\nTransfer U-Boot & Linux to target device\n"

[ $# -lt 1 ] && echo "Please input target device, e.g. ./mksd-linux.sh /dev/mmcblk0" && exit 1
[ ! -e $1 ] && echo "Device $1 not found" && exit 1
[ "`cat /sys/block/${1##*/}/device/type`" == "SD" ] && echo "Device $1 is type of SD." && exit 1

echo "All data on "$1" now will be destroyed! Continue? [y/n]"
read ans
if [ $ans != 'y' ]; then exit 1; fi

echo 0 > /proc/sys/kernel/printk

echo "[Unmounting all existing partitions on the device ]"

umount $1* &> /dev/null

echo "[Partitioning $1...]"

DRIVE=$1

cd ../image

filename="fsl-image*.sdcard"
current_filename=`ls | grep fsl-image*.sdcard`

if [ -e $filename ];then
    echo "[Copy $current_filename image]"
    dd if=$current_filename of=$1 &>/dev/null
else
    echo $filename does not exist
    exit 1
fi

echo "[Resize filesystems...]"

rootfs_start=`fdisk -u -l ${DRIVE} | grep ${DRIVE}p2 | awk '{print $2}'`

# Create partition table for extend root file system (/dev/mmcblk1p2) partition
fdisk -u $DRIVE << EOF &>/dev/null
d
2
n
p
2
$rootfs_start

w
EOF

if [ -x /sbin/partprobe ]; then
    /sbin/partprobe ${DRIVE} &> /dev/null
else
    sleep 1
fi

e2fsck -f -y ${DRIVE}p2 &> /dev/null
resize2fs ${DRIVE}p2 &> /dev/null

if [ -x /sbin/partprobe ]; then
    /sbin/partprobe ${DRIVE} &> /dev/null
else
    sleep 1
fi

echo 7 > /proc/sys/kernel/printk
echo "[Done]"

MKSD_EOF
$ sudo cp ${MKSD} ~/mnt/p2/mk_inand/

Other Features

• see Linux Features