According to a slide leaked on Weibo, ARM will have a total of five new CPU cores for 10nm and 16nm class processes. If legit, the slide points to a new direction for ARM – instead of having two cores like the current Cortex-A57 and Cortex-A53, the company will introduce a new medium tier.
ARM’s core reshuffle
The news comes just a few weeks after we published an analysis of SoC design trends this year, suggesting that we will see very few new Cortex-A57 designs. Most chipmakers are waiting for Cortex-A72 and filling the mid-range gap with octa-core Cortex-A53 designs.
The leaked roadmap suggests we were right to predict a new mid-range ARMv8 design, but let’s start with the top tier first.
The Cortex-A72 will eventually be replaced by Ares, a 10nm design with a power envelope of 1-1.2W per core. However, Ares is not designed for smartphones – it will go after server/enterprise clamshell markets and large tablets.
The Cortex-A57 will be replaced by Prometheus 10nm parts, (600-750mW per core) and will be used in flagship phones and tablets.
This is where it gets interesting. Part of the A57 and A17 segment will be replaced by Artemis, a 16nm design with the same power envelope as Prometheus. However, the upcoming Ananke core will replace the 32-bit A17 and part of A53 segments. It will be used in entry to mid-range mobiles, with big.LITTLE support.
Ananke and Mercury are designed for high efficiency, at 100-250mW and 50-150mW respectively. The latter is going after ultra-low cost mobiles and wearables. It will replace some Cortex-A53 parts, along with 32-bit A7 and A5 cores.
The only problem with the roadmap is that we have no idea when the new designs will come online. ARM doesn’t even say which node Ananke and Mercury are designed for. Ares and Prometheus are designed for 10nm, while Artemis is supposed to end up in 16nm class designs.
This suggests Artemis will be the first part to launch, which is good news, as it will supplement and replace A57 and A17 parts in the performance segment.