Device Tree Overlays with Yocto-project

Hi, I have a question.
I´m working with a module imx6ull in yocto-project, and I need build a device tree overlay for custom the device tree. But I don´t understad where I build my overlays for compiler.

Hi @facundo.n.r !

Which exact Colibri iMX6ULL are you working with? To be able to use Device Tree Overlays with this module, it must be the eMMC version instead of NAND. The NAND ones don’t support Device Tree Overlays.

Please share the full name and version of your Colibri iMX6ULL. Also, please share the BSP version you are using.

To get started with Device Trees, we recommend you take the time to read our documentation about Device Tree (and Device Tree Overlays).

Please let us know if this helps you.

Best regards,

Hi @henrique.tx , I´m working with Colibri IMX6ULL 512MB WB IT V1.1 A, it include WIFI and Bluetooth, and Im using the version kirstone 6.x.y.

Can this module use device tree overlays?

I saw on the forum how to create device tree overlays (DTOs), but I have some questions.

I understand that the configuration is:

  1. Create a layer
  2. Inside the layer, create a recipe, with a device-tree-overlays folder that containing the .dts files. Also, you need to create a .bbapend file.

After, Do execute bitbake device-tree-overlays or I have to do another setup before?

Hi @facundo.n.r !

Only Colibri iMX6ULL 1GB RAM is eMMC, so your module has raw NAND, therefore your module doesn’t support Device Tree Overlays (only Device Tree). You can easily check it on NXP i.MX 6ULL - Arm Computer/System on Module iMX6ULL, enabling the “Table view” at the right of the page and comparing the Memory.

Best regards,

Hi @facundo.n.r !

Regarding how to build the device tree overlays, please refer to the following articles:

Best regards,

Thank you @herique.tx, and now for modifying the device tree.
What´s better?

Build Linux Kernel from Source Code: Build Linux Kernel from Source Code | Toradex Developer Center

Or modify the files .dts and add my configuration on the file imx6ull-colibri-eval-v3.dts

those articles:

Are they compatible with my module NAND?

Hi @facundo.n.r !

Depends on your needs.

If you modify Toradex files, you will need to keep an eye on the upcoming updates to keep your patches applicable.

If you create and maintain your own Device Tree source code files, it may be easier on you maintenance-wide.

As pointed out previously, Raw NAND modules have no support for Device Tree Overlays. This aspect is not dependent on the approach to building the Device Tree Overlays.

Best regards,

I’m sorry, but I don’t understand.
Are you saying that I can apply these instructions in my module?

Hi @facundo.n.r !

Your module (Colibri IMX6ULL 512MB WB IT V1.1 A) does not support Device Tree Overlays.

I am saying the opposite: no device tree overlay approach will work on your module.

Best regards,

Thanks for your time.
Do you have any recommendations for modifying the device tree in my module?

Hi @facundo.n.r !

I recommend you invest time reading our nice documentation about Device Tree. By following it I am sure you will have a nice understanding of Device Trees in general and how you can use/customize/build/deploy them specifically for Toradex modules.

Best regards,

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