Hi, On Fri, Apr 23, Paul Graham wrote:

Unfortunately, most of the ARM hardware I am looking at does not have UEFI support. They tend to require U-Boot. Given that, what is expected of the bootloader to use it with MicroOS? I know that U-Boot has a "distro boot" configuration now that might make it easier to use out-of-the-box OS images.

We create many MicroOS images for ARM. Best is to look at the kiwi file for this images, then it should be clear what is needed. There is no separate documentation.

Also, the ARM SoCs have particular features that make them useful for my applications, but sometimes those features are not yet in the upstream Linux kernel. Additionally, I sometimes have to build custom kernels even when using the upstream kernel source. If I need a custom kernel (from the device vendor or otherwise), is there a reasonable way to support this situation with MicroOS? In the past, I have created my own kernel package (with a different name) and managed things that way.

You can do the same things with MicroOS as you do with Tumbleweed, except that MicroOS has a read-only root filesystem and uses transactional updates. So yes, you can of course continue to build your own kernel. Thorsten

Anyway, if you can point me to some documentation, that would be very helpful.

Thanks!

Paul

On Wed, Mar 31, 2021 at 6:56 PM Anthony J Rabbito <hello@anthonyrabbito.com> wrote:

...

Hi Paul,

You may be best off getting your custom arm device to boot to standard aarch64 UEFI then having kubic take over from there.

The alternative route would be to bake yourself a custom KIWI OEM image.

Kubic gets build here: https://build.opensuse.org/package/show/devel:kubic:images/openSUSE-MicroOS Kiwi Docs are here: https://osinside.github.io/kiwi/quickstart.html Thanks, Anthony

On Mar 31 2021, at 8:49 pm, Paul Graham <pgrahamdev@gmail.com> wrote:

Is it possible to use a custom kernel and bootloader with MicroOS? I ask specifically because I am interested in supporting some specific ARM devices that may require custom kernel and bootloader support. WIth other Linux distributions, I effectively can package up my custom kernel and bootloaders and use them instead of the stock versions. At that point, I am mainly just using the userland software from the distribution, of course.

If it is possible to use custom kernels and bootloaders, are there specific changes/support required for U-Boot or the kernel to support MicroOS and its many features beyond what a regular openSUSE distribution might need?

Thanks!

Paul

-- Thorsten Kukuk, Distinguished Engineer, Senior Architect SLES & MicroOS SUSE Software Solutions Germany GmbH, Maxfeldstr. 5, 90409 Nuernberg, Germany Managing Director: Felix Imendoerffer (HRB 36809, AG Nürnberg)

Never mind. I found the information in Anthony's email above. Paul On Fri, Apr 23, 2021 at 11:59 AM Paul Graham <pgrahamdev@gmail.com> wrote:

Thanks for the pointers and responses!

I have one additional question for now. Where can I find the kiwi files for the MicroOS images (or other relevant images)? I found the examples referenced in the kiwi docs (https://github.com/OSInside/kiwi-descriptions), but I couldn't locate the kiwi files for MicroOS there or with a simple search in the openSUSE source on GitHub.

Thanks again,

Paul

On Fri, Apr 23, 2021 at 10:49 AM Thorsten Kukuk <kukuk@suse.de> wrote:

...

Hi,

On Fri, Apr 23, Paul Graham wrote:

...

Unfortunately, most of the ARM hardware I am looking at does not have UEFI support. They tend to require U-Boot. Given that, what is expected of the bootloader to use it with MicroOS? I know that U-Boot has a "distro boot" configuration now that might make it easier to use out-of-the-box OS images.

We create many MicroOS images for ARM. Best is to look at the kiwi file for this images, then it should be clear what is needed. There is no separate documentation.

...

Also, the ARM SoCs have particular features that make them useful for my applications, but sometimes those features are not yet in the upstream Linux kernel. Additionally, I sometimes have to build custom kernels even when using the upstream kernel source. If I need a custom kernel (from the device vendor or otherwise), is there a reasonable way to support this situation with MicroOS? In the past, I have created my own kernel package (with a different name) and managed things that way.

You can do the same things with MicroOS as you do with Tumbleweed, except that MicroOS has a read-only root filesystem and uses transactional updates. So yes, you can of course continue to build your own kernel.

Thorsten

...

Anyway, if you can point me to some documentation, that would be very helpful.

Thanks!

Paul

On Wed, Mar 31, 2021 at 6:56 PM Anthony J Rabbito <hello@anthonyrabbito.com> wrote:

...

Hi Paul,

You may be best off getting your custom arm device to boot to standard aarch64 UEFI then having kubic take over from there.

The alternative route would be to bake yourself a custom KIWI OEM image.

Kubic gets build here: https://build.opensuse.org/package/show/devel:kubic:images/openSUSE-MicroOS Kiwi Docs are here: https://osinside.github.io/kiwi/quickstart.html Thanks, Anthony

On Mar 31 2021, at 8:49 pm, Paul Graham <pgrahamdev@gmail.com> wrote:

Is it possible to use a custom kernel and bootloader with MicroOS? I ask specifically because I am interested in supporting some specific ARM devices that may require custom kernel and bootloader support. WIth other Linux distributions, I effectively can package up my custom kernel and bootloaders and use them instead of the stock versions. At that point, I am mainly just using the userland software from the distribution, of course.

If it is possible to use custom kernels and bootloaders, are there specific changes/support required for U-Boot or the kernel to support MicroOS and its many features beyond what a regular openSUSE distribution might need?

Thanks!

Paul

-- Thorsten Kukuk, Distinguished Engineer, Senior Architect SLES & MicroOS SUSE Software Solutions Germany GmbH, Maxfeldstr. 5, 90409 Nuernberg, Germany Managing Director: Felix Imendoerffer (HRB 36809, AG Nürnberg)