Scheduling (unused) board file removal for linux-6.x

[Rob Herring]

On Wed, Jun 29, 2022 at 2:44 PM Arnd Bergmann <arnd at kernel.org> wrote:
>
> With the multiplatform work completed in the past merge window, and the
> scheduled deprecation of the Samsung s3c platforms, I decided to have a
> look at the remaining board files. There are 196 remaining boards, down
> from 489 boards ten years ago, but my estimate is that only few of those
> ever booted a linux-5.x kernel, and even less for future kernels. The
> question is how to find out which ones are still used, and which ones
> can go.
>
> I would propose that we start by changing the assumption that all boards
> might be used, instead assuming that they are all outdated unless someone
> says that they actually prefer to keep it in the kernel.  I have started
> a list of all 196 boards and annotated the ones that look like candidates
> for removal [1]. If a board you use is on that list, please either reply
> here or add a comment in the document.
>
> Unless someone has a better idea for how to proceed, I would allow
> six months for users to speak up and then remove the orphaned board
> files for the release following the LTS kernel. I can't list all boards
> individually, so here is a breakdown by platform:
>
> s3c24xx
>
> These are all scheduled for removal in early 2023 already, once the next
> longterm stable kernel is out. No changes here, but it seems useful
> to use the same timeline for removing unused board files of the other
> platforms together.
>
> s3c64xx
>
> There are ten board files, which are currently scheduled for removal in
> 2024, along with the DT based boards for this SoC. We can still decide
> to throw out some of the board files earlier though, while keeping the
> platform around.
>
> cns3xxx
>
> There is only one reference board here, the actual products that were
> previously supported, none of the board files from openwrt (now gone) made
> it in, and the DT support was never completed, so the entire platform can
> go away. We could also consider dropping the other arm11mpcore platforms
> (oxnas and the mpcore variants of realview/integrator) at the same time,
> since there are known issues with the CPU core.
>
> iop32x
>
> Some of the NAS devices were still in use two years ago as they have
> a lot of RAM for an ARMv5 based machine, not sure if they still are
> used. If they are, a DT conversion similar to what we did for ixp4xx
> should be possible.
>
> pxa
>
> There are a ton of boards on this one, including seven with qemu support,
> but based on IRC discussions, my feeling is that everyone who worked on
> this has already lost interest a few years ago. There is rudimentary DT
> support, so it may be helpful to pick one or two boards (gumstix?) with
> good qemu support and keep them around for conversion to DT, while
> removing all other boards.

FWIW, u-boot is removing all PXA support.

Rob