SolidRun's i.MX8MP build scripts

Introduction

Main intention of this repository is to produce a reference system for i.MX8MP based product evaluation. Automatic binary releases are available on our website IMX8MP_Images for download.

The build script provides ready to use Debian/Buildroot images that can be deployed on micro SD and eMMC.

Compiling Image from Source

Configuration Options

The build script supports several customisation options that can be applied through environment variables:

• BOOTSOURCE: Select bootloader media
  • mmc-data (SD/eMMC Data Partition, default)
  • mmc-boot0 (eMMC Partition boot0)
  • mmc-boot1 (eMMC Partition boot1)
• DISTRO: Choose Linux distribution for rootfs
  • buildroot (default)
  • debian
• BUILDROOT_VERSION: Select version of buildroot
  • 2023.11 (default)
• BUILDROOT_DEFCONFIG: Select buildroot defconfig file name from config/ folder
  • buildroot_defconfig (default)
• BUILDROOT_ROOTFS_SIZE: Specify rootfs size
  • 448M (default)
• BR2_PRIMARY_SITE: Use specific (local) buildroot mirror
• DEBIAN_VERSION
  • bullseye (default)
• DEBIAN_ROOTFS_SIZE
  • 936M (default)
• OPTEE_STORAGE_PRIVATE_RPMB: enable optee-os secure storage on emmc rpmb partition
  • true (default)
• OPTEE_STORAGE_PRIVATE_REE: enable optee-os secure storage with insecure real-world fs
  • false (default)

Example

generating buildroot image

./runme.sh

generating debian image

DISTRO=debian ./runme.sh

Build with Docker

A docker image providing a consistent build environment can be used as below:

1. build container image (first time only)

   docker build -t imx8mp_build docker
   # optional with an apt proxy, e.g. apt-cacher-ng
   # docker build --build-arg APTPROXY=http://127.0.0.1:3142 -t imx8mp_build docker
   

2. invoke build script in working directory

   docker run -i -t -v "$PWD":/work imx8mp_build -u $(id -u) -g $(id -g)
   

rootless Podman

Due to the way podman performs user-id mapping, the root user inside the container (uid=0, gid=0) will be mapped to the user running podman (e.g. 1000:100). Therefore in order for the build directory to be owned by current user, -u 0 -g 0 have to be passed to docker run.

Deploying

SD

Default sdcard images combine bootloader and operating system in a single image generated during the build: images/<distro>-bootimg>-<hash>.img

For installation to a microSD card use etcher.io or Unix dd command:

# ensure card is not mounted
umount /dev/sdX*
# write image
sudo dd if=images/<distro>-bootimg>-<hash>.img of=/dev/sdX

Note: dd command will eat your data, carefully substitute sdX with the name of the actual device representing the microSD connected to your PC!

Finally connect microSD card to the device and set boot-switches accordingly.

eMMC

1. Boot from a bootable microSD card per instructions above.

2. Interrupt at the U-Boot console by pressing a key at the prompt:

   ...
   Normal Boot
   Hit any key to stop autoboot:  0
   u-boot=>
   

3. Configure the target eMMC partition for bootloader by executing the respective U-Boot command (choose one):

   • data: mmc partconf 2 1 7 0
   • boot0: mmc partconf 2 1 1 1
   • boot1: mmc partconf 2 1 2 2

   Using the boot0 partition is recommended unless special requirements dictate otherwise.

4. Prepare a USB flash drive with the Bootloader and OS images to be programmed to the eMMC:

   USB Flash drive should be formatted FAT32 (readable by most PCs) or EXT4 (readable from Linux only), then copy the following files as needed:

   • images/<distro>-bootimg>-<hash>.img -> bootimg.img (for OS & Bootloader combined)
   • images/<distro>-rootimg>-<hash>.img -> rootimg.img (for OS only)
   • images/u-boot-mmc-data-<hash>.bin -> u-boot-mmc-data.bin (for eMMC data partition)
   • images/u-boot-mmc-boot0-<hash>.bin -> u-boot-mmc-boot0.bin (for eMMC boot0 partition)
   • images/u-boot-mmc-boot1-<hash>.bin -> u-boot-mmc-boot1.bin (for eMMC boot1 partition)

5. Install Bootloader:

   Connect the prepared USB flash drive, confirm the board can see it's files:

   u-boot=> usb start
   starting USB...
   Bus usb@32e40000: USB EHCI 1.00
   scanning bus usb@32e40000 for devices... 3 USB Device(s) found
          scanning usb for storage devices... 1 Storage Device(s) found
   u-boot=> ls usb 0:1 /
   696254464   bootimg.img
   696254464   rootimg.img
     1166536   u-boot-mmc-boot0.bin
     1166536   u-boot-mmc-boot1.bin
     1166552   u-boot-mmc-data.bin
   
   5 file(s), 0 dir(s)
   

   Then install bootloader to the previously chosen and ocnfigured eMMC partition:

   • data:

      u-boot=> load usb 0:1 $kernel_addr_r u-boot-mmc-data.bin
      u-boot=> setexpr nblocks 0x$filesize + 0x1ff
      u-boot=> setexpr nblocks 0x$nblocks / 0x200
      u-boot=> mmc dev 2 0
      switch to partitions #0, OK
      mmc2(part 0) is current device
      u-boot=> mmc write $kernel_addr_r 0x40 0x$nblocks
     
      MMC write: dev # 2, block # 64, count 2279 ... 2279 blocks written: OK
     

   • boot0:

      u-boot=> load usb 0:1 $kernel_addr_r u-boot-mmc-boot0.bin
      u-boot=> setexpr nblocks 0x$filesize + 0x1ff
      u-boot=> setexpr nblocks 0x$nblocks / 0x200
      u-boot=> mmc dev 2 1
      switch to partitions #0, OK
      mmc2(part 1) is current device
      u-boot=> mmc write $kernel_addr_r 0 0x$nblocks
     
      MMC write: dev # 2, block # 0, count 2279 ... 2279 blocks written: OK
     

   • boot1:

      u-boot=> load usb 0:1 $kernel_addr_r u-boot-mmc-boot1.bin
      u-boot=> setexpr nblocks 0x$filesize + 0x1ff
      u-boot=> setexpr nblocks 0x$nblocks / 0x200
      u-boot=> mmc dev 2 2
      switch to partitions #0, OK
      mmc2(part 2) is current device
      u-boot=> mmc write $kernel_addr_r 0 0x$nblocks
     
      MMC write: dev # 2, block # 0, count 2279 ... 2279 blocks written: OK
     

6. Install OS:

   TBD.

7. Finally set boot-switches for eMMC, remove microSD and power-cycle the board.

Boot Select

| SolidSense N8 Boot Select (DIP-Switch S1) | 1 | 2 | | micro-SD | ON | ON | | eMMC | OFF | ON |

Login

• username: root
• password: root