Flashing SD Card with Linux Image using the USB Serial Downloader

Installing Using USB Serial Downloader Protocol (SDP)

The preferred method of installing Yocto images to SD card is this: Flashing SD Card with Linux Image from Linux Host. However sometimes, extracting the SD card from the kit is not possible (for example, when the kit is installed to a device and is not easily accessible). In this case, use the method below.

Perform the following step-wise procedure to install the Yocto images to SD card installed into i.MX 8M NAVQ Plus kit:

Power the kit off by disconnecting the USB Type C cable from the development host.
Set the target boot mode to the USB serial downloader mode by setting the boot switches as follows:
- SW2.1 - 1
- SW2.2 - 0
Power the kit on by connecting the USB Type C cable to the development host. Use the kit port labeled USB1.

Check that the new USB device has appeared on your development host:

[psl@i7 ~]$ lsusb | grep -i nxp 
Bus 001 Device 025: ID 1fc9:0146 NXP Semiconductors

On the host, go to the Yocto images directory:
```
[psl@i7 ~]$ cd ~/5-15-5-DESKTOP/builddir/tmp/deploy/images/imx8mpnavq 
[psl@i7 imx8mmnavq]$ ls -1
...
imx-boot-imx8mpnavq-sd.bin-flash_evk
imx-image-desktop-ros-imx8mpnavq.wic.bz2
uuu
...
```
- The images above are:
- imx-boot-imx8mpnavq-sd.bin-flash_evk - U-Boot-ATF-OPTEE boot image;
- imx-image-desktop-ros-imx8mpnavq.wic.bz2 - Ubuntu 20 root filesystem;
- uuu - pre-built image of the uuu utility (you could also use pre-built uuu image from https://github.com/NXPmicro/mfgtools/releases/latest, or build it from sources https://github.com/NXPmicro/mfgtools/tree/master);

Unpack the compressed image of the root filesystem:

[psl@i7 imx8mmnavq]$ bzip2 -d imx-image-desktop-ros-imx8mpnavq.wic.bz2
...

Launch the uuu tool with appropriate script as a parameter for installing the bootable Linux image:

[psl@i7 imx8mmnavq]$ sudo ./uuu -v -b sd_all imx-boot-imx8mpnavq-sd.bin-flash_evk imx-image-desktop-ros-imx8mpnavq.wic
uuu (Universal Update Utility) for nxp imx chips -- libuuu_1.3.82-0-g9c56e46

Wait for Known USB Device Appear...

The uuu tool will proceed to install the Production Yocto image to the storage device (SD card) on the target board:

uuu (Universal Update Utility) for nxp imx chips -- libuuu_1.3.74-2-g302da91 

Success 1 Failure 0
...
1:3 7/ 7 [Done ] FB: Done

When uuu has finished, the bootable Linux image has been installed to the on-module storage. Given proper setting of the boot switches, next power-on will boot the target board from the SD storage device.

Verifying New Installation

Perform the following step-wise procedure to verify boot of the newly installed Linux images from the SD card plugged into the kit:

Power the kit off by disconnecting the USB Type C cable from the development host.
Select the appropriate boot mode (boot from SD) by setting the boot switches as follows:
- SW2.1 - 1
- SW2.2 - 1
Power the kit on by connecting the USB Type C cable to the development host.

Verify that the following Linux boot-up messages appear on the serial console:

NOTICE:  BL31: v2.4(release): 
NOTICE:  BL31: Built : 05:49:10, Mar  2 2022


U-Boot 2021.04-lf_v2021.04+g60519b47e7 (Jul 31 2022 - 08:56:04 +0000)

CPU:   i.MX8MP[8] rev1.1 1800 MHz (running at 1200 MHz)
CPU:   Commercial temperature grade (0C to 95C) at 44C
Reset cause: POR
Model: Voxelbotics NAVQ+ board
DRAM:  4 GiB
...
Starting kernel ...

[    0.000000] Booting Linux on physical CPU 0x0000000000 [0x410fd034]
...
Ubuntu 20.04.3 LTS imx8mpnavq ttymxc1

imx8mpnavq login:

Enter the Linux session by typing user for both the user name and password.