Re: What's the plan for powerpc64 in FreeBSD 16

----- Original Message -----
> From: "Piotr Kubaj" <[email protected]>
> To: "Al" <[email protected]>
> Cc: "Poul-Henning Kamp" <[email protected]>, "Minsoo Choo" <[email protected]>, "Warner Losh" <[email protected]>,
> "[email protected]" <[email protected]>, "freebsd-ppc" <[email protected]>
> Sent: Wednesday, November 26, 2025 3:01:26 PM
> Subject: Re: What's the plan for powerpc64 in FreeBSD 16

> On 25-11-26 15:47:38, Al wrote:
>> 
>> On Wed, 26 Nov 2025, Poul-Henning Kamp wrote:
>> 
>> > Date: Wed, 26 Nov 2025 17:07:23 +0000
>> > From: Poul-Henning Kamp <[email protected]>
>> > To: Minsoo Choo <[email protected]>
>> > Cc: Warner Losh <[email protected]>,
>> >     "[email protected]" <[email protected]>
>> > Subject: Re: What's the plan for powerpc64 in FreeBSD 16
>> > 
>> > Minsoo Choo writes:
>> >
>> >> After reading replies, I still have questions why we should keep powerpc64be.
>> >
>> >> Second, regarding arguments about keeping big-endian support in codebase even
>> >> if no one actually physically runs the code:
>> >> This also applies to leaving 32-bit code (armv7) in tree for future
>> >> compatibility.
>> >
>> > I think that is a bit of a leap, although in principle I agree.
>> >
>> > However, I am much less convinced that a relevant new 32 bit platform
>> > will appear, than that somebody comes out with a 64 BE platform.
>> >
>> > Bit-rot is a thing, and unless we are willing to say "Screw anybody
>> > silly enough to create BE platform now or in the future" we should
>> > still guard against it.
>> 
>> There is a number of new PowerPC 64 BE systems:
>> A1222
> BE, but not 64-bit. It's supported via powerpcspe port on FreeBSD, which
> is already deprecated along with powerpc.
>> Sam460 several versions
> I'm not sure about that, I think it's also 32-bit.
>> Mirari (New PPC hardware)
> This one will be ugly, similarly to e5500. e5500 is 64-bit, but without
> Altivec, so it's below the usual baseline. Mirari will use e6500. e6500
> supports BE with Altivec. It also supports LE, but without VSX. The
> current baseline for LE is POWER8, which supports VSX.
> e5500 works on FreeBSD, but requires building everything on your own,
> along with the OS itself, by using CPUTYPE?=e5500 in make.conf,
> otherwise Altivec instructions will be issued by clang. If we ever get
> binary packages on powerpc64, e5500 users will still need to build their
> own because of that.

If that's correct, then ABIv2 would be broken in LE mode, making LE mode even less useful on that hardware.  I really don't want to be forced to keep the early ABI support around just for quite old, fairly quirky cores.