How to upgrade yocto from one version to another one

[Tech_Traveler]

Hello everyone,

Sorry if someone already asked this  question, but I have looked all around and have not found yet an answer for my concern.

I'm using a custom board made of the "VAR-SOM-DUAL" development kit using a NXP imx6 DL processor.

The board is working with Yocto Kogroth on it. I would like to upgrade yocto to Dunfell (That's what was asked) but do not know where to exactly start in a step-by-step manner.

The board has a SIM card (with all the drivers that goes with it), python applications on it, an eMMC chip has been added on it in addition to the NAND and a couple of other things. 

I have found this link: https://docs.yoctoproject.org/3.3/ref-manual/migration.html

allowing to migrate Yocto step-by-step from one version to the next one (Which I like). My questions is the following:

• Since I want to go from Kogroth to Dunfell (Jump over a couple of version: Around 8), How would you do that in a step-by-step manner?
• Do I need to it manually from one version after another one? (There must be a more efficient way out there).
• What about the applications. How would go about updating them if needed? and see the dependencies that are needed.

Thank you for you time and insights.

[Tech_Traveler]

Hi @hector_delgado 

I have done some modifications starting with the u-boot recipe to boot Dunfell (I have a eMMC and a NAND on the board).

• The system can boot uboot (when choosing eMMC until the Kernel says "starting the kernel" and stays there forever). 
• When trying to boot form the NAND, the uboot won't work and the kernel as well.

Anyone has met a similar case when updating a yocto version?

[hector_delgado]

Hi @Tech_Traveler ,

If you are upgrading over multiple releases, you will need to follow the sections from the version following the one you were previously using up to the new version you are upgrading to.

The link you provided opens an outdated version of the Yocto Project Documentation, here is the up-to-date version: 
Welcome to the Yocto Project Documentation — The Yocto Project ® 4.1.999 documentation

And here is the introductory section regarding migration to newer versions of the Yocto Project:
Introduction — The Yocto Project ® 4.1.999 documentation

In the Introduction section you'll find the following info:
"This guide provides a list of the backwards-incompatible changes you might need to adapt to in your existing Yocto Project configuration when upgrading to a new release.

If you are upgrading over multiple releases, you will need to follow the sections from the version following the one you were previously using up to the new version you are upgrading to."

Regarding your third question, you'd need to check the corresponding documentation and information for each application and adapt them as needed.

I hope you find this information useful.

Best regards,
Hector Delgado.

[Tech_Traveler]

Hi Hector,

Thanks for your quick answer.

I appreciate your time to explain me better how to do all of that and the path I need to follow. 

So If I understand correctly, I will need to update manually each version from the one following the one I'm using (Kogroth) until the one I want to use (Dunfell) with all the modifications they advised at each version. Then Make the version work. And when done, switch to the following version and do the same until I reach the version I want?

I will need to build each version in-between Kogroth and Dunfell to be able to test (with the modifications on the Yocto General Migration considerations link) them I suppose?

Is there an automatic way to do update from one version to the following one? I keep my fingers crossed. lol

For the kernel and the U-boot, Should I jump directly to the Dunfell version of it or still do it for each version in-between?

Thanks very much for your help, it's really precious.

P.S: I will follow your advice to update the applications, recipes, layers, etc

[hector_delgado · Accepted solution]

Hi @Tech_Traveler ,

Yes, you'll need to manually upgrade to each version of Yocto from Kogroth up until Dunfell. I'd recommend the same for the kernel and the u-boot if specified any important changes in the Yocto Porject User Guide and the Yocto Project Reference Manual.

Unfortunately, there's no automatic way at the moment.

Best regards,
Hector Delgado.