Maynard Handley (name99.delete@this.name99.org) on February 4, 2015 11:42 am wrote:
> You don't think they'll at least add the ARMv8.1 RMW atomics? (Not that that changes performance
> substantially, but I imagine they want that part of the ISA to be universalized ASAP.)
>
>

No I do not think so.

All cores used in a big-little configuration must be on the exact same architectural level, either ARMv7, ARMv8 or ARMv8.1. Because A72 are designed to be paired with A53, this implies A72 can never support the ARMv8.1 programming model.

Of cause it is possible that the a A72 chip will implement ARMv8.1, but initially disabled until the little cores start to support ARMv8.1. If that is the case, then I really hope that ARM's marketing department is wise enough to allocate a new model number for ARMv8.1 compatible cores. Otherwise 'Cortex-A72 with ARMv8.1 Feature Set' is such a mouth full.

Ronald