Background of splitting the metadata and FIT image creation into two repos

[shoudil]

Currently dtb metadata and FIT generation scripts are maintained in two repos respectively. Is the any plan to centralized the FIT creation in this qcom-dtb-metadata as well ? If not, what is the consideration behind this ?
Thanks.

FIT creation script:
https://github.com/qualcomm-linux/kmake-image/blob/main/make_fitimage.sh
dtb metadata:
https://github.com/qualcomm-linux/qcom-dtb-metadata

[lool]

It looks like kmake-image is a collection of utilities for the kernel team to build kernels, including the FIT image generation.

I'd very much like to move the FIT image generation closer to the data it needs/processes (qcom-dtb-metadata) as to use these in other projects (qcom-deb-images, perhaps meta-qcom would be amenable too, I guess this would also be worth considering for qcom-distro-images).

[NainaMehtaQUIC]

There is a limitation that ITS can't be built without the actual DTB(O)s that it is referencing and these DTB(O)s are not available in qcom-dtb-metadata. The kmake-image tool takes care of fetching the kernel source which wouldn't be possible in the current project.

[lool]

There is a limitation that ITS can't be built without the actual DTB(O)s that it is referencing and these DTB(O)s are not available in qcom-dtb-metadata. The kmake-image tool takes care of fetching the kernel source which wouldn't be possible in the current project.

Would you think it is possible to provide the tool next to the ITS data and call it from kmage-image (kernel team), meta-qcom, or qcom-deb-images?

[lool]

Responses to questions from @NainaMehtaQUIC (out of band):

We don’t have FIT image support in qcom-deb-images, and I understand what’s needed for it. Basically in qcom-deb-images we already have a tarball with dtbs, and we use it to generate dtb.bin FAT images. My simple idea is:

• Make sure all relevant DTBs are installed by the kernel (this is a separate issue)
• Create a stateless script next to qcom-dtb-metadata that takes a .its file as input and a path to a directory full of DTBs, and outputs the FIT image; similar to the kernel build script https://github.com/qualcomm-linux/qcom-deb-images/blob/main/scripts/build-linux-deb.py
• Use this script from qcom-deb-images and replace the implementation in meta-qcom, make-kernel-package, qcom-distro-images to call that scripts instead

[shoudil]

Responses to questions from @NainaMehtaQUIC (out of band):

We don’t have FIT image support in qcom-deb-images, and I understand what’s needed for it. Basically in qcom-deb-images we already have a tarball with dtbs, and we use it to generate dtb.bin FAT images. My simple idea is:

• Make sure all relevant DTBs are installed by the kernel (this is a separate issue)
• Create a stateless script next to qcom-dtb-metadata that takes a .its file as input and a path to a directory full of DTBs, and outputs the FIT image; similar to the kernel build script https://github.com/qualcomm-linux/qcom-deb-images/blob/main/scripts/build-linux-deb.py
• Use this script from qcom-deb-images and replace the implementation in meta-qcom, make-kernel-package, qcom-distro-images to call that scripts instead

Issue was created qualcomm-linux/kernel-topics#849 to track this:

• Make sure all relevant DTBs are installed by the kernel (this is a separate issue)

[NainaMehtaQUIC]

Hi @vkraleti, can you please confirm if it would be feasible to call make_fitimage.sh from below to create FIT image in meta-qcom if we add make_fitimage.sh in qcom-dtb-metadata?

https://github.com/qualcomm-linux/meta-qcom/blob/5b44f6c9c8b342d582f35033826edcfd7b6d306a/classes-recipe/dtb-fit-image.bbclass#L102
https://github.com/qualcomm-linux/meta-qcom/blob/5b44f6c9c8b342d582f35033826edcfd7b6d306a/classes/linux-qcom-dtbbin.bbclass#L30

[NainaMehtaQUIC]

Responses to questions from @NainaMehtaQUIC (out of band):

We don’t have FIT image support in qcom-deb-images, and I understand what’s needed for it. Basically in qcom-deb-images we already have a tarball with dtbs, and we use it to generate dtb.bin FAT images. My simple idea is:

• Make sure all relevant DTBs are installed by the kernel (this is a separate issue)
• Create a stateless script next to qcom-dtb-metadata that takes a .its file as input and a path to a directory full of DTBs, and outputs the FIT image; similar to the kernel build script https://github.com/qualcomm-linux/qcom-deb-images/blob/main/scripts/build-linux-deb.py

ITS file would also need the path for all the DTBs and would require update as per the path passed to the script.
If a user has to add a new DTB(O), user will need to update the ITS file accordingly before running the script.

[NainaMehtaQUIC]

Hi,

We are planning to implement the following approach.

1. DTBO installation would be addressed through the changes introduced in arm64: dts: qcom: Install DTBO overlays kernel-topics#887.
2. The FIT image generation script will be ported to the qcom-dtb-metadata project.
3. A wrapper will be added around the FIT generation script to support DEB and RPM packages.
4. The FIT generation script can also be leveraged to build a standalone FIT image with meta-qcom. @vkraleti can help provide additional information on meta-qcom-related aspects.

We would appreciate your feedback on this approach.

[vkraleti]

meta-qcom only uses qcom-metadata.dts DT from this project. OE provides a U-boot aligned FIT generation bbclass and meta-qcom uses it instead of make_fitimage.sh for FIT image generation.