Re: [PATCH v3 08/10] x86: document X86_INTEL_MID as 64-bit-only

Andy Shevchenko
2025-02-28T18:40:59Z

On Fri, Feb 28, 2025 at 05:20:54PM +0100, Ferry Toth wrote:
> Hi,
>
> On 26-02-2025 22:37, Arnd Bergmann wrote:
> > From: Arnd Bergmann <arnd@arndb.de>
> >
> > The X86_INTEL_MID code was originally introduced for the 32-bit
> > Moorestown/Medfield/Clovertrail platform, later the 64-bit
> > Merrifield/Moorefield variants were added, but the final Morganfield
> > 14nm platform was canceled before it hit the market.
> >
> > To help users understand what the option actually refers to, update the
> > help text, and add a dependency on 64-bit kernels.
> >
> > Ferry confirmed that all the hardware can run 64-bit kernels these days,
> > but is still testing 32-bit kernels on the Intel Edison board, so this
> > remains possible, but is guarded by a CONFIG_EXPERT dependency now,
> > to gently push remaining users towards using CONFIG_64BIT.
>
> That is a bit more than I said :-) I only know of Merrifield, as Andy
> removed the SFI bits and got ACPI working. For the other platforms I don't
> know the status. Additionally there are pieces of code where 32b runs
> substantially faster than 64b (I know of at least crc32c).
>
> Maybe Andy can confirm the other platforms?

Listed SoCs are all capable of running 64-bit code.

Telling that they 64-bit only is a bit of a lie but it seems for good. :-)

OTOH I dunno if there is still a plan by community to resurrect Intel Medifield
and Clovertrail (there are phones in a working shape still around), but either
way they will need to switch to ACPI and U-boot to begin with and that's in my
knowledge not trivial and not easy task. That said, I don't think it will ever
happen.

--
With Best Regards,
Andy Shevchenko