Creating a Linux image for a custom board - how????

[cbcooper]

I've inherited a custom board that contains (among other things) an STM32MP135AAE3, an eMMC, and an Ethernet controller (DP83826ERHBR).  No SD card, no HDMI, no keyboard.  For that matter, no JTAG (board error). 

I had thought about running Zephyr but it's looking like that's not currently possible (discussion here).

The documentation for creating a Linux image for this chip seem to fall under two categories:

1) If you are using one of the development kits, here are explicit step-by-step instructions that will make it a joy

2) If not, here (thud) are the manuals for yocto, bitbake, repo, and really the entire Linux kernel.  Read them all, digest them completely, and the answer will be obvious.

Am I missing something?  Are there instructions somewhere to help me create a Linux image?  I don't need to become a yocto expert, I just need to create one Linux image one time.

Thanks,

Chris

[Jean-Christophe_TROTIN]

Hi @cbcooper,

I could suggest that you have a look at the following documents (if not already done):

• https://wiki.st.com/stm32mpu/wiki/How_to_create_your_own_image: this article highlights several chapters of the Yocto documentation that might be useful for you.
• https://wiki.st.com/stm32mpu/wiki/How_to_create_your_own_distribution: this article points out some configuration examples.

Hope this information helps.

Regards,

JC.

[cbcooper]

Hi,

Unfortunately both of those pages show the problem I was describing.

Despite its name, "How to create your own image" does not tell you how to create your own image.  I'm sure if you have been working with yocto for a while it is all crystal clear, but the page mostly explains what some of the files in the OpenSTLinux folder are, and then has a link to the yocto "megamanual".  I'm sure I'm not the only developer out here who doesn't want to become a yocto expert, I just want to write a program that runs on this chip.  I understand that some customization is required because my board will have different components from your discovery board, but that learning curve is just way too steep.

"How to create your own distribution" is also just a thin layer over the yocto mega-manual.  It does point to "How to create a new open embedded layer" which is much better, but unfortunately still requires a large investment in understanding yocto in order to put that information to use.

For now, I don't see creating my own Linux distro as being at all feasible, and it looks like Zephyr is not ready for prime time.  We need to do a board spin, I'm going to highly recommend not using anything in the STM32MP13 family.

What would change my mind is a process like this:

Step 1: Here is a list of applications and libraries you need to download & install.

Step 2: Run this script, telling it which chip you are using, it will generate the necessary yocto files as much as it can (obviously it doesn't know what I've got connect to the chip on my board).  These files will be generated outside of the yocto folders so you can check them into your repo.

Step 3: Here is the file you need to edit and some basic information about what things you need to change.

Step 4: Here is a 'build' command that actually works