[meta-mender-tegra] self update single copy machinism

[EasyIP2023]

I've briefly looked into to mender and was wondering if it is possible to do single copy updates like with swupdate? (https://sbabic.github.io/swupdate/overview.html#single-copy). Would prefer this update approach as it helps with reduction of the overall image size. Also, would rather not do dual copy A/B partition approach. Per looking into swupdate doesn't seem to work with nvidia's L4T C-boot for xavier series boards. If single-copy update approach isn't possible would it be possible to switch from c-boot over to u-boot? Or is nvidia not having it like is say in this forum post https://forums.developer.nvidia.com/t/custom-u-boot-on-xavier-solved/65885/2

[kekiefer]

Conceivably, one could boot into the recovery mode kernel + initrd to prepare the system for an upgrade. As for the feasibility of doing this with Mender, someone else would have to say. I've only seen full A/B and delta update done with mender.

Support for t19x u-boot does not exist, and sounds unlikely considering NVIDIA's recent moves towards EFI boot schemes for mainline support instead.

[EasyIP2023]

Thanks

[ichergui]

@EasyIP2023

SWUpdate requires u-boot, maybe some image types that are not support yet such as WIC image.

Nvidia Tegra194 SOC doesn't support u-boot, I believe that is difficult to adapt software update mechanism when using Nvidia bootloader cboot.

Also, Kernel and DTB are installed in different partition, and the complicated part is when secure boot is enable (images are signed). I don't know how SWUpdate manage this.

As @kekiefer mentioned, maybe delta update with mender will be interesting for you.

[kekiefer]

SWUpdate requires u-boot, maybe some image types that are not support yet such as WIC image.

To be clear, I think you mean to say that the swupdate single copy mechanism requires u-boot, which may be true. A/B update with swupdate and cboot is no problem.

[EasyIP2023]

Thanks guys

[ichergui]

Please refer to the link1 and link2

[ichergui]

@EasyIP2023

You're welcome

[dwalkes]

One comment I wanted to add about this:

If single-copy update approach isn't possible would it be possible to switch from c-boot over to u-boot?

I'm not sure if you've noticed this but both c-boot and u-boot are going the way of the dodo bird with Jetpack 5, so it would be better to end up with something which was as decoupled as possible from either. Also, with u-boot you can end up with multiple sources of truth for rootfs which can be confusing and difficult to manage. See discussion at sighthoundinc/meta-mender-community#1 for details.

Update has been a hot topic recently. There's been discussion in the meeting this week and on the slack channel, so you might be able to collaborate with others if you are just starting out on this.