How to enable a device tree with Yocto?

[rockerr]

I'm working with Yocto and an imx evaluation board. I want to enable the imx93-11x11-evk-aud-hat.dtb device tree to enable the aud-hat, what are the steps to do that?

This question is really about enabling any device tree build into a dtb file other than the main board file - imx93-11x11-evk.dts. I cannot find any information about enabling custom device trees, not even that aud hat device tree. The build .dtb files are present in tmp/deploy/images/imx93-11x11-evk-... directory, however when the imaged is flashed on the SD card it seems to lack the dtb files, I couldn't find the imx93-11x11-evk-aud-hat.dtb file on the running system.

[brian14]

Hi @rockerr, 

Thank you for contacting NXP Support. 

To properly list and enable a device tree from the BSP you will need to follow these steps:

1. Use the following command to list interfaces
 

=> mmc list
Output example
=> FSL_SDHC: 1 (SD)
=> FSL_SDHC: 2

 The above command will show you the device number in this example for SD, the device number is 1
2. Then use fatls <interface> <device[:partition]> [<directory>]
 

fatls mmc 1:1
(Device 1 : Partition 1)

 With this command, we will be able to list device tree files.
 

=> fatls mmc 1:1

 3. Select your device tree and use the command editenv fdtfile 
 

=> editenv fdtfile 
Output example
edit: imx8mp-evk-basler.dtb

4. In edit command line put the selected device tree .dtb
5. Use saveenv command to save environment and continue with the boot process.

I hope this information will be helpful.