New ARM products: the Cortex A72, the CCI 500 and the Mali T880
At the beginning of February this year, ARM announced the launch of its Cortex‑A72, CCI‑500 and Mali‑T880 for "high end" mobile solutions. Just two years ago, ARM already attracted a great deal of attention with its Cortex‑A50, its first step in the 64-bit universe in the early days of ARMv8 architecture. Shortly thereafter, the Cortex‑A50 family grew with the addition of the Cortex‑A53 and Cortex‑A57, which could be coupled with big.LITTLE architecture to achieve significant power savings during low-energy usage. Though we’re barely beginning to see real-world commercial applications of the Cortex A57 and Mali-T760, ARM is showing all the signs of leading the pack and setting the pace in 2016 with this latest announcement.
The Cortex‑A53 has a new, more powerful sibling with ARM’s latest addition to the family, the Cortex‑A72, which takes ARM processors to a whole new level of performance on a lower power budget. This makes it the highest-performing processor of the ARMv8‑A family at a time when 4K video requires at least 64 bits of processing power, though its 32-bit base makes it backward-compatible. This means 16nm FinFET implementations can reach speeds of 2.5 GHz, though the architecture has been designed to enable even greater performance.
The Cortex-A72 promises a 3.5x increase in sustained performance over the 32-bit Cortex‑A15 launched in 2014, with its 28nm technology, which is the current standard on the mobile market. But this latest arrival sports major improvements in ARMv8‑A microarchitecture for performance enhancements such as memory management and floating point number handling. Enhanced energy efficiency reduces consumption by 75% as compared with the Cortex‑A15 for equivalent tasks.
The Cortex‑A72 high-level architecture is based on Cortex‑A50 functionality on the NEON SIMD engine with support for the floating point number. The instruction cache supports parity while the data cache supports the ECC, as is the case with the L2 cache. But the Cortex‑A72 also supports the Accelerator Coherency Port (ACP) (optional) and the Snoop Control Unit (SCU). The SCU’s snoop filter now resides on the interconnect itself rather than within the core for optimal cache management and energy efficiency. The 128-bit external Coherency interface can be AMBA 4 ACE or AMBA 5 CHI.
The CoreLink CCI‑500 (SoC Interconnect)
With the CoreLink CCI‑500 SoC interconnect, ARM claims a 30% processor memory performance improvement over the CCI‑400, introduced three years ago. Further, the CCI‑500 should offer twice as much bandwidth, at 34 GB/s, i.e. three times as much as high-end smartphones currently on the market. This significant increase will easily support the display of 4K content on mobile devices. 4K specifications are quite demanding, with 4 times more pixels per inch than HD displays.
Further, the CCI‑500 will allow a 12% efficiency gain in system memory thanks to the integrated snoop filter mentioned above. The role of snoop filters is to maintain a common directory of cache contents in order to free up bandwidth for reduced energy consumption, and to free up resources for use by other applications.
Another advantage of the CoreLink CCI‑500 is its flexibility and scalability, enabling it to meet the needs of both mobile devices and enterprise servers.
The Mali‑T880 GPU
ARM also announced an addition to the Mali‑T800 GPU family, with the new T880 completing the T820, T830 and T860 series. Like the other new products, this new GPU will offer enhanced performance and energy efficiency compared to previous versions.
The new GPU will support games with complex graphics and enable UHD content visualisation on mobile devices. ARM’s Mali‑T880 GPU is scalable from 1 to 16 cores and delivers 1.8 times more performance and 40% more energy efficiency when compared to the Mali‑T760.
The new GPU can be coupled with the Mali-V550 VPU and Mali-DP550 DPU for enhanced HD video compression (HEVC) and image post-processing from the GPU. Finally, the Mali‑T880 supports TrustZone media protection, thereby enabling a secure video path for 4K content.
The stage is set for 2016 in the field of mobile devices. I can’t wait to see how the competition will react to ARM’s announcements. One thing is certain: the Cortex‑A72, the CoreLink CCI‑500 and the Mali‑T880 GPU will be part of our device future.