[OpenPower-Firmware] Dropping Power8 in op-build

[Klaus Heinrich Kiwi]

On 6/17/2020 4:58 AM, Joel Stanley wrote:
> On Wed, 17 Jun 2020 at 05:38, Paul Menzel
> <pmenzel+openpower-firmware at molgen.mpg.de> wrote:
>> It looks like they are held up due to failing in IBM internal build
>> environment. Can that internal environment be integrated into the public
>> CI infrastructure?
> 
> If the reason we can't merge is internal CI fails to build, won't that
> same internal CI fail to build if we remove Power8 from the tree and
> update to the newer compilers?

I think Dean and Dan can better comment on this, but my take is that the Hostboot team
(as well as SBE, OCC etc) have a Power8 branch, on which we based several of our products,
and they're maintaining that branch as those products still require them. Since those are
long-term products in "fixes" mode only, they'd prefer not to change the toolchain
from underneath it, adding risk to existing products using them and essentially having
to re-validate all of them end-to-end.

  
> I can't see the downside to merging these patches in. There's no
> guarantee of support or testing, but it allows folks like Paul to
> still build from master, and take advantage of updates to skiboot,
> buildroot and Linux.


I believe it would require the HB, OCC, SBE teams etc to perform "a branch of a branch",
i.e., continue to maintain the branch in which we have products still in service,
while creating a new branch, that sits somewhere in between "hostboot-p8" and
"hostboot-master", that is able to drive the Power8 chip while still tolerating newer
compilers and toolchains (and new features?).


If IBM won't create and maintain that branch, it is still possible for someone else to fork
and do it, which is still compatible with my proposal below.

>>> My proposal here is to remove all Power8 support from master op-build,
>>> and if someone is still interested in
>>> maintaining a Power8 branch, we have op-build-2.5.y or other older
>>> branches available for that (patches welcome),
>>> or one could fork and maintain their own tree (I'd be happy to point to
>>> it in our official documentation).
>>
>> As patches are available, it’d be great to keep POWER8 in master. No
>> idea, how to solve the issue with the internal build tools conflict.

  -Klaus

-- 
Klaus Heinrich Kiwi <klaus at linux.vnet.ibm.com>