[yocto] Problems building core-minimal-rt on Jethro (2.0.1) and Krogoth (2.1)

[Bruce Ashfield]

On 2016-05-04 10:02 AM, Ronald Oakes wrote:
> My project will need to be real-time (we're probably putting a crystal
> controlled clock in), so I'd like to have the real-time kernel.  So,
> I've been attempting to build core-minimal-rt on both 2.0.1 and 2.1.
> I get errors on both, albeit different errors.
>
> Jethro:
>
> On 2.0.1, the do-patch for linux-yocto-rt-* fails, ultimately with the
> message: "Your branch is behind 'origin/standard/preempt-rt/base' by
> 691 commits, and can be fast-forwarded." followed by "(use "git pull"
> to update your local branch)"
>
> I get this error on all distros, including poky-bleeding.  I've not
> been successful in disabling the mirrors just for linux-yocto-rt.  I
> am now trying a build, albeit on my slow machine (two cores, where if
> I don't force bitbake into running one task at a time, it hangs),
> after deleting everything except the conf directory to see if that
> makes any difference
>
> Krogoth:
>
> On 2.1, the error message occurs very quickly:
>
> ERROR: Nothing PROVIDES 'linux-yocto-rt' (but
> /home/ron/yocto_2.1/poky/meta/recipes-rt/images/core-image-rt.bb
> DEPENDS on or otherwise requires it)
> ERROR: linux-yocto-rt was skipped: PREFERRED_PROVIDER_virtual/kernel
> set to linux-yocto, not linux-yocto-rt
> ERROR: linux-yocto-rt was skipped: PREFERRED_PROVIDER_virtual/kernel
> set to linux-yocto, not linux-yocto-rt
> NOTE: Target 'linux-yocto-rt' is unbuildable, removing...
> Missing or unbuildable dependency chain was: ['linux-yocto-rt']
> NOTE: Target 'core-image-rt' is unbuildable, removing...
> Missing or unbuildable dependency chain was: ['core-image-rt', 'linux-yocto-rt']
> ERROR: Required build target 'core-image-rt' has no buildable providers.
> Missing or unbuildable dependency chain was: ['core-image-rt', 'linux-yocto-rt']
>
> ---
>
> Any clues as how to work around either?

On 2.1, set:

PREFERRED_PROVIDER_virtual/kernel = "linux-yocto-rt"

I also have all my latest SRCREV commits here:

git://git.pokylinux.org/poky-contrib master:zedd/kernel

That's the latest 4.1 and 4.4 -rt changes that I'm about to send
to the mailing list.

Bruce

>
> Ron Oakes
>