Samsung Electronics Co. Ltd. surprised a few people when it kept them guessing about the graphics core inside the Exynos Octa mobile applications processor launched at the beginning of the year. (See: London Calling: Whose GPU in Exynos Octa?)
Six months on and the company has now appears to be running a two-horse strategy with regard to licensing in graphics. Having launched the Exynos 5410 Octa with PowerVR SGX544MP from Imagination Technologies Group plc as the graphics processor in January, the company has now announced the Exynos 5420 Octa with a six-core Mali T628 from ARM Holdings plc as the graphics engine.
That's good news for ARM, dispelling the idea of a glass ceiling above which it might struggle to gain design wins.
Samsung has been a major licensor of ARM processor cores, and the Octa was itself a lead implementation of ARM's big-little strategy for running applications with energy efficiency by pairing off Cortex-A15 and Cortex-A7 processor cores. So Samsung's jump to PowerVR was a blow to ARM's aspirations to compete at the leading-edge in licensable GPUs. ARM had achieved success in licensing a large number of second-tier design wins in Southeast Asia, but it looked as if Imagination was holding and even regaining ground at the high-end of the market with high volume SoC vendors.
So Samsung's jump back to Mali is good for ARM, particularly as Samsung has been prepared to publicly compare the two iterations of Exynos 5 Octa -- although clearly the implementation and the number of cores deployed is a design choice rather than a direct comparison of the two architectures.
The Exynos 5420, based on the Mali T628 MP6 achieves twice the graphics processing capability of its 5410 predecessor. However, it is also clear that Samsung has brought the Mali T628 into Exynos for its ability to perform general-computing, otherwise known as GPU-compute. Samsung also claims to have tweaked the big-little 4x4 processor design to obtain a further 20 percent power saving over the previous chip.
While the Exynos 5410 began shipping in the second quarter, the 5420 is now sampling to customers and is scheduled for mass-production in August.
What is clear, as with the recent AnTuTu benchmarking affair, is that the system part of SoC is most important when it comes to working out computational and power efficiencies. Such things as the inclusion of the right compression/decompression engine for graphics textures, the right caching strategy, and the right ports to off-chip memory storage -- possibly more so than the native architecture -- are keys to achieving the right performance and power consumption and getting design wins.
So with this win ARM has turned the tide somewhat. Imagination will almost certainly be designed-in elsewhere with its PowerVR Series 6 GPUs, including with Samsung, and in so doing will oust ARM's Mali. But the rising significance of GPU-compute means that when it comes to graphics there is no glass ceiling -- and between Imagination and ARM it is "game on."