The Cortex A57 succeeded the Cortex A15 and was ARM’s first “big” core to employ ARMv8 64-bit ISA. Accompanied by the high-efficiency Cortex A53 cores this represented an important shift not unlike the x86-64 introduction in the desktop PC space well over a decade before. The cores came at a moment where the industry was still at shock of Apple’s introduction of the A7 SoC and Cyclone CPU micro-architecture, beating ARM in terms delivering the first 64-bit ARMv8 silicon. Suddenly everybody in the industry was playing catch-up in trying to bring their own 64-bit products as it was seen as an absolutely required feature-check to remain competitive.
This pressured shift to 64-bit was in my view a crippling blow to many 2015’s SoCs as it forced vendors into employing sub-optimal Cortex A57 and A53 designs. HiSilicon and MediaTek saw an actual regression in performance as flagship SoCs such as the Kirin 930 and Helio X10 had to make due with only A53 cores for performance as they decided against employing A57 cores due to power consumption concerns. The Kirin 930 or the X10 were in effect slower chipsets than their predecessors. Only Samsung was fairly successful in releasing reasonable designs such as the Exynos 5433 and Exynos 7420 – yet these had respectively regressed or barely improved in terms of power efficiency when compared to mature Cortex A15 implementations such as the Exynos 5430. Then of course we had sort of a lost generation of devices due to Qualcomm’s unsuccessful Snapdragon 810 and 808 SoCs, a topic we’ll eventually revisit in our deep dive of the Snapdragon 820 and Exynos 8890.
