Deploy kernel and/or device tree

This topic shows how to quickly deploy a customized kernel and/or device tree to your target device.

The methods explained in this topic are for manual deployment during the development phase. For production-ready firmware updates see:

After customizing the kernel source code, you may have built just the kernel recipe or a full Digi Embedded Yocto image recipe.

Program single files

If you built only the kernel recipe, you can find the kernel binary and device tree blobs in the tmp/deploy/images/ccimx93-dvk/ folder of your project. You can deploy these single files to your linux partition, which is formatted in FAT file system.

Update files from the operating system

The linux partition is automatically mounted to /mnt/linux, but as a read-only file system.

Remount the linux partition with read/write permissions:
```
# mount -o remount,rw /mnt/linux
```

Copy the kernel file, device tree blob, or device tree overlay, from the development computer to the target, for example via SSH:

$ scp tmp/deploy/images/ccimx93-dvk/Image.gz-ccimx93-dvk.bin root@<cc93-IP>:/mnt/linux/
$ scp tmp/deploy/images/ccimx93-dvk/your-platform.dtb root@<cc93-IP>:/mnt/linux/
$ scp tmp/deploy/images/ccimx93-dvk/your-dt-overlay.dtbo root@<cc93-IP>:/mnt/linux/

Run sync on the target to make sure Linux writes the changes to the file system:
```
# sync
```

Reboot the target to load the new files.

U-Boot loads:

the kernel file pointed to by environment variable imagegz
the device tree pointed to by variable fdt-file
the device tree overlays in variable overlays

Check if you need to change the values of these U-Boot variables to point to your new files.

Update files from U-Boot

Place the file or files you want to update (kernel file, device tree blob, or device tree overlays) into your TFTP exposed folder. You can alternatively use an external media, such as a USB disk or a microSD card.
Power on your target and press any key to stop automatic U-Boot boot process.
Run the updatefile command to copy the files from the development computer to the target, for example via TFTP:
```
=> updatefile linux tftp <filename>
```

See Update files within partition, for additional information.

Program image files (full partition update)

If you built a full image recipe (dey-image-qt, for example), Digi Embedded Yocto generates an image file for the linux partition, such as dey-image-qt-xwayland-ccimx93-dvk.boot.vfat.

Place the image file into your TFTP exposed folder. You can alternatively use an external media, such as a USB disk or a microSD card.
Boot the target and press any key to stop the automatic U-Boot boot process.
Run the update command to update the entire linux partition, for example via TFTP:
```
=> update linux tftp <image-filename>
```

See Program images from U-Boot for additional information on updating from U-Boot.