Re: Deprecate the ppc405 boards in QEMU? (was: [PATCH v3 4/7] MAINTAINERS: Orphan obscure ppc platforms)

["Daniel P. Berrangé" <berrange@redhat.com>]

On Tue, Oct 05, 2021 at 06:44:23AM +0200, Christophe Leroy wrote:
> 
> 
> Le 05/10/2021 à 02:48, David Gibson a écrit :
> > On Fri, Oct 01, 2021 at 04:18:49PM +0200, Thomas Huth wrote:
> > > On 01/10/2021 15.04, Christophe Leroy wrote:
> > > > 
> > > > 
> > > > Le 01/10/2021 à 14:04, Thomas Huth a écrit :
> > > > > On 01/10/2021 13.12, Peter Maydell wrote:
> > > > > > On Fri, 1 Oct 2021 at 10:43, Thomas Huth <thuth@redhat.com> wrote:
> > > > > > > Nevertheless, as long as nobody has a hint where to find that
> > > > > > > ppc405_rom.bin, I think both boards are pretty useless in QEMU (as far as I
> > > > > > > can see, they do not work without the bios at all, so it's
> > > > > > > also not possible
> > > > > > > to use a Linux image with the "-kernel" CLI option directly).
> > > > > > 
> > > > > > It is at least in theory possible to run bare-metal code on
> > > > > > either board, by passing either a pflash or a bios argument.
> > > > > 
> > > > > True. I did some more research, and seems like there was once
> > > > > support for those boards in u-boot, but it got removed there a
> > > > > couple of years ago already:
> > > > > 
> > > > > https://gitlab.com/qemu-project/u-boot/-/commit/98f705c9cefdf
> > > > > 
> > > > > https://gitlab.com/qemu-project/u-boot/-/commit/b147ff2f37d5b
> > > > > 
> > > > > https://gitlab.com/qemu-project/u-boot/-/commit/7514037bcdc37
> > > > > 
> > > > > > But I agree that there seem to be no signs of anybody actually
> > > > > > successfully using these boards for anything, so we should
> > > > > > deprecate-and-delete them.
> > > > > 
> > > > > Yes, let's mark them as deprecated now ... if someone still uses
> > > > > them and speaks up, we can still revert the deprecation again.
> > > > 
> > > > I really would like to be able to use them to validate Linux Kernel
> > > > changes, hence looking for that missing BIOS.
> > > > 
> > > > If we remove ppc405 from QEMU, we won't be able to do any regression
> > > > tests of Linux Kernel on those processors.
> > > 
> > > If you/someone managed to compile an old version of u-boot for one of these
> > > two boards, so that we would finally have something for regression testing,
> > > we can of course also keep the boards in QEMU...
> > 
> > I can see that it would be usefor for some cases, but unless someone
> > volunteers to track down the necessary firmware and look after it, I
> > think we do need to deprecate it - I certainly don't have the capacity
> > to look into this.
> > 
> 
> I will look at it, please allow me a few weeks though.

Once something is deprecated, it remains in QEMU for a minimum of two
release cycles, before being deleted. At any time in that deprecation
period it can be returned to supported status, if someone provides a
good enough justification to keep it.

IOW, we can deprecate this now, and you still have plenty of time to
investigate more.


Regards,
Daniel
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