Re: [PATCH 0/2] powerpc: Remove support for ppc405/440 Xilinx platforms

[Christophe Leroy]

Le 21/05/2020 à 12:38, Christophe Leroy a écrit :
> Le 21/05/2020 à 09:02, Michael Ellerman a écrit :
> > Arnd Bergmann <arnd@xxxxxxxx> writes:
> > > +On Wed, Apr 8, 2020 at 2:04 PM Michael Ellerman <mpe@xxxxxxxxxxxxxx> wrote:
> > > > Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> writes:
> > > > > On Fri, 2020-04-03 at 15:59 +1100, Michael Ellerman wrote:
> > > > > > Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> writes:
> > > > > IBM still put 40x cores inside POWER chips no ?
> > > >
> > > > Oh yeah that's true. I guess most folks don't know that, or that they
> > > > run RHEL on them.
> > >
> > > Is there a reason for not having those dts files in mainline then?
> > > If nothing else, it would document what machines are still being
> > > used with future kernels.
> >
> > Sorry that part was a joke :D  Those chips don't run Linux.
>
> Nice to know :)
>
> What's the plan then, do we still want to keep 40x in the kernel ?
>
> If yes, is it ok to drop the oldies anyway as done in my series 
> https://patchwork.ozlabs.org/project/linuxppc-dev/list/?series=172630 ?
>
> (Note that this series will conflict with my series on hugepages on 8xx due to the 
> PTE_ATOMIC_UPDATES stuff. I can rebase the 40x modernisation series on top of the 8xx hugepages 
> series if it is worth it)

Do we still want to keep 40x in the kernel ? We don't even have a running 40x QEMU machine as far as 
I know.

I'm asking because I'd like to drop the non CONFIG_VMAP_STACK code to simplify and ease stuff (code 
that works with vmalloc'ed stacks also works with stacks in linear memory), but I can't do it 
because 40x doesn't have VMAP_STACK and should I implement it for 40x, I have to means to test it.

So it would ease things if we could drop 40x completely, unless someone there has a 40x platform to 
test stuff.

Thanks
Christophe