[PATCH v2] arm: Support initrd with address in boot alias region

[Arnd Bergmann]

On Thu, Aug 18, 2022 at 2:28 PM Matija Glavinic Pecotic
<matija.glavinic-pecotic.ext at nokia.com> wrote:
>
> On 18.08.2022 14:03, Arnd Bergmann wrote:
> > I think the logic looks correct, but I' would not put this into init/initramfs.c
> > when the problem is specific to Arm. The function is called from
> > arch/arm/mm/init.c, so you could just put it there.
> >
> > I'm fairly sure that only keystone2 is affected by this, so it might
> > even be possible to do this inside of keystone specific code,
> > e.g. in keystone_pv_fixup(), which is called a little earlier.
>
> Thanks, I agree initramfs was wrong place to put it.
>
> I will find better place, however since idmap is generic (although with
> only one known user platform), I'd like to keep it for arm in general.

Let's see if Russell has an opinion either way. I think at the time the idmap
code was added, the expectation was that additional platforms might
need it, but now it should be a fairly safe assumption that this won't
be the case. This was really only needed for keystone2 because it
supports a large amount of RAM in 2012, but this was also the peak
point of available RAM. Later chips either went with 64-bit cores, or
they have narrower DDR3 interfaces that only allow at most 2GB
of RAM.

> Let me prepare next patch.

Thanks,

        Arnd