According to projections made by ARM and Gartner, 580 million mid-range smartphones and tablets will be sold in 2015. In preparation for this ARM has updated its mid-range offering and replaced the Cortex-A9 with the Cortex-A12. On top of the performance and energy improvements the A12 adds hardware support for OS virtualization and can address up to 1 Terabyte of physical memory. The A12 can also be used in a big.LITTLE configuration bringing the advantages of that architecture to the mid-range.
This is what the specification of the Cortex-A12 look like on paper:
- ARMv7-A Cortex Architecture
- Multicore 1-4X SMP within a single processor cluster
- Multiple coherent processor clusters through AMBA® 4 technology
- TrustZone® security technology
- NEON™ Advanced SIMD
- DSP & SIMD extensions
- VFPv4 Floating point
- Hardware virtualization support
- Large Physical Address Extensions (LPAE)
TrustZone is a security related technology that is used in a range of applications including digital rights management and electronic payments. The NEON instructions are used to accelerate multimedia program such as video decoding and speech processing, while the DSP & SIMD extensions increase the DSP processing capability of the CPU and are used for things like Voice over IP (VOIP) as well as in video & audio codecs.
Because the Cortex-A12 uses the same ARMv7A architecture as the Cortex-A9 it is fully software compatible with the other Cortex processors and will support Android, Linux and even Windows right out of the box.
[quote qtext=”Mobile users expect a range of devices at different price points and for a mid-range mobile experience to include some high end mobile features.” qperson=”Ian Drew, an EVP of ARM” qsource=”” qposition=”left”]
There has been lots of discussion about the big.LITTLE architecture along with some recent worries about Samsung’s current implementation in the Exynos Octa 5. However it looks like big.LITTLE is here to stay as ARM has added the ability to use the Cortex-A12 in a big.LITTLE setup along with the Cortex-A7, effectively taking the place of the more expensive and power hungry Cortex-A15. This means that we will see more big.LITTLE implementations on mid-range SoCs in the future.
GPU and video processing
ARM has improved the GPU in the Cortex-A12. The new Mali-T622 is smaller and brings 50% energy efficiency improvements over the original Mali-T604. It also supports Renderscript Compute, OpenGL ES 3.0, DirectX 11 and OpenCL 1.1. The new design can be used in a dual core configuration and can handle 4x Full Scene Anti-Aliasing (FSAA) with a minimal performance drop.
New to the Cortex-A12 is the addition of a dedicated video processing unit. The Mali-V500 is a multicore video solution and by adding it ARM have reduced the system bandwidth requirements by more than 50 percent when compared to the current solutions. It can handle encoding and decoding video at 1080p/60 with a single core and when scaled to a multiple core solution, it can support ultra-high definition 4K at an amazing 120 frames per second.
In the server room
Many of the features found in the new Cortex-A12 won’t be used in smartphones but are aimed at the server room. With operating systems like Linux running comfortably on ARM and with the chips low energy consumption, the new A12 could be a good choice for data centers and server rooms. Now with added support for Hardware Virtualization the Cortex-A12 can be used in environments that need virtual machine hypervisors. Combined with LPAE the processor can access up to 1TB of memory. Although these features also exist in the Cortex-A15, it is interesting to see ARM include them in a mid-range processor, clearly it is thinking about low priced, energy efficient server solutions.
The Cortex-A9 was announced in 2007 and has served the mobile device market well, but things move fast in technology and it was time the architecture was updated. Its replacement, the A12, is faster, more energy efficient and adds a whole range of new features like big.LITTLE, virtualization and LPAE. If the history of the A9 is anything to go by, the A12 should be with us for the next five years or more. If you buy a mid-range Android smartphone in 2014 it could well be powered by this design.