"Beyond Buildworld" (was Re: RFC: "Crochet" build tool)

[Warner Losh]

On Apr 6, 2013, at 3:09 PM, Adrian Chadd wrote:
> FreeBSD doesn't necessarily need to support all of that, at least just yet.

I tend to agree, but only to a point. We should have a long-range plan in mind, as well as a long term destination. We need not hit that with the first iteration, but each iteration should get us closer.

> I think we'd be in a good position if we had build scripts and base
> support to build a variety of target system filesystem configurations
> and images; then leave it up to an external project (which may or may
> not _be_ at freebsd.org, but it doesn't have to be in /usr/src) that
> builds the platform specific stuff. That way we don't get bogged down
> with bootloaders and such at this stage.

Yes. We don't want to be in the boot loader business. The board should provide. Unfortunately, most board providers don't yet support the callback API that we need to support the ubldr. We should accept that there will be a wide range of versions and possibly even different loaders like barebox. Linux is able to cope by having a very standardized interface. We don't have that now, and we should adopt one. We're currently not likely large enough to do anything other than the Linux interface.

> Ideally i'd like to see all of those bootloaders and tools in
> /usr/src, just like we do for booting i386/amd64/etc systems. That way
> we _do_ have a nice, tightly integrated system. But I think that's a
> stretch goal.

I'd opt for a ports solution to the bare-metal loader. The experience that we had with AT91 suggests supporting a wide range of boards with the bare-metal loaders is very hard, and we don't have the bandwidth to do this.

Warner