On Thu Sep 22, 2022 at 4:50 AM AEST, Segher Boessenkool wrote:

On Wed, Sep 21, 2022 at 11:41:02AM +1000, Nicholas Piggin wrote:

quoted

Big-endian GENERIC_CPU supports 970, but builds with -mcpu=power5.
POWER5 is ISA v2.02 whereas 970 is v2.01 plus Altivec. 2.02 added
the popcntb instruction which a compiler might use.

Use -mcpu=power4.

Fixes: 471d7ff8b51b ("powerpc/64s: Remove POWER4 support")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>

Reviewed-by: Segher Boessenkool <redacted>

Thank you!

Maybe superfluous, but some more context: GCC's -mcpu=power4 means
POWER4+, ISA 2.01, according to our documentation.  There is no
difference with ISA 2.00 (what plain POWER4 implements) for anything
GCC does.

Huh, okay. Well I guess we are past that point now, interesting that
another ISA version was done for 4+ though, and then another for 5.
I don't see a list of changes from 2.00 in the public version, I
wonder what else changed other than mtmsrd.

Thanks,
Nick