[v2] Old platforms: bring out your dead

[Arnd Bergmann]

On Sun, Jan 17, 2021 at 11:33 AM Michael Ellerman <mpe at ellerman.id.au> wrote:
> Arnd Bergmann <arnd at kernel.org> writes:
> > On Fri, Jan 15, 2021 at 9:37 PM John Paul Adrian Glaubitz
> > <glaubitz at physik.fu-berlin.de> wrote:
> >>
> >> Hello Arnd!
> >>
> >> > * No objection to removing arch/powerpc/platforms/cell that I
> >> >   had mentioned I plan to do.
> >>
> >> Does this affect the capability to run Linux on the PS3?
> >>
> >> If yes, it would be great if it could stay as the PS3 is a rather
> >> widely used platform although you certainly won't find any PS3
> >> users on the LKML.
> >
> > No, as I wrote in the initial email, I'm planning to move the things
> > (like spufs) that are shared with PS3 into arch/powerpc/platforms/ps3
> > and remove the parts that are only used on the IBM blades.
>
> As I said a while back, I'm not convinced that's a good idea.
>
> The only way I have of testing cell is using a QS22, I don't have a PS3
> capable of running Linux these days. I worry that if I can't test cell
> at all then the PS3 support will bit rot.

Fair enough. I must have missed your previous reply and expected
that your QS22 had stopped being operational years ago and that
there were already zero machines getting kernel updates.

Are you aware of any other users?

> I know Geoff tests PS3, but that seems sporadic, I don't think he tests
> linux-next every day.
>
> I also don't think the cell blade support is really causing much in the
> way of maintenance overhead. The thing that's causing work is spufs, and
> that would remain either way.
>
> I'd be happy to drop any QS20/21 code we have, but I'm not convinced
> dropping QS22 is a good trade off.

Right, I agree that there is little to gain from dropping QS20/21, the
only files that I see this would impact are

arch/powerpc/platforms/cell/spider-pci.c
arch/powerpc/platforms/cell/spider-pic.c
drivers/net/ethernet/toshiba/spider_net*

Dropping all of native (as opposed to PS3 hypervisor based) Cell support
would be a useful cleanup I think, but not as long as you still use it.

        Arnd