Tock: Host OpenTitan boot rom?

[ppannuto]

1935 raised a good point that pointing to a random azure cloud build link isn't terribly reliable.

Proposal: We host a copy of the image on www.tockos.org.

I think the way to do this is to use git-lfs. Netlify has first-class support for large artifacts stored in LFS being served (i.e. I do this for ppts and videos on my personal website). It works great.

Holler if folks have other thoughts?

Attn: @alistair23

[alistair23]

Does the license for the boot ROM allow this? My main concern was that we wouldn't be allowed to duplicate the boot ROM.

[ppannuto]

@tock/opentitan-wg Any thoughts on this? Either Tock hosting a copy or providing something more canonical than an Azure build link for those who need images?

[gkelly]

So long as the terms of the license are respected I don't think there are any issues. Currently the boot ROM isn't nearly as full-featured as it's going to end up being, and isn't changing very rapidly right now. We're looking to spin up development in about a month's time and we can start discussing what a reasonable release mechanism is then.

[ppannuto]

Okay, I have to confess some OT ignorance here: what I know of this boot ROM is that you can download it from a magic Azure link Alistair has provided and (from a quick search) its documentation is here: https://docs.opentitan.org/sw/device/boot_rom/README/ (?). What license / potential license issues do we need to be looking at here?

[gkelly]

The boot ROM code is Apache 2.0, so we're very aligned with the Tock side of things. The azure link you're getting is probably just a CI link that includes a boot ROM image as part of the normal build flow. We'll probably switch to tagged releases when the boot ROM stabilizes, and so there will be a stable GCS link for the artifacts.

[bradjc]

I fully support this. I also think we should add the FPGA bitstream as well.

[ppannuto]

Can you drop a link / copy of the bitstream here? I need to set up some things on the netlify side, but I'll do them together in a little bit.

[lschuermann]

Has someone considered Zenodo, maybe if only as a secondary mirror?
Given OpenTitan's nature and Tock's role in research I think this could be a reasonable platform.

[ppannuto]

I've happily used Zenodo for research stuff before (indeed, it backs the datasets for DATA). I probably don't want to upload someone else's artifact there though.

Happy to point to artifacts there if OT folks are willing to publish them that way.

[hudson-ayers]

Relying on the OpenTitan CI artifact for our CI is continuing to cause issues, most recently in libtock-rs as the disappearing artifacts force libtock-rs to update to the latest upstream Tock submodule in order to run the QEMU tests. From reading this thread it doesn't sound like hosting a copy of the boot ROM on TockOS should be an issue, I think it would be great if we could move forward with that approach.

[alistair23]

Just to clarify, to host it in the Tock repo?

[brghena]

I believe the thinking was to host it in the Tock website somewhere: https://github.com/tock/tock-www. That way we could reliably access it and update it if needed through PRs. But also people who don't need it don't have to download it with the repo clone.

[jrvanwhy]

We plan to host a copy of the Mask ROM (previously called the boot ROM) in a GCS bucket. I'll send a PR when that is available to point Tock at the GCS bucket rather than OpenTitan's CI artifacts. That should resolve the CI reliability issues currently caused by the boot ROM.

[hudson-ayers]

Closed by #2170 🎉