Understanding PowerVR Series5XT: PowerVR GPUs and graphics API standards
On March 15th, Samsung announced their flagship Galaxy S4 smartphone – powered by their own Samsung Exynos 5 Octa SoC with a PowerVR Series5XT SGX544MP3 GPU core. Samsung’s return to PowerVR should be no surprise given the defining role played by the SGX540 in the original Galaxy and for Imagination, it’s simply a continuation of the remarkable success story of this PowerVR Series5XT GPU IP core.
The Exynos 5 Octa processor inside the Samsung Galaxy S4 uses a PowerVR SGX544MP3 GPU
The PowerVR SGX544 graphics processor was released in 2010 which may lead to the false conclusion that it is an ‘old’ GPU; however reality couldn’t be more different and with this article I’d like to provide an exciting insight into the market leading feature set, architectural efficiency, software stack and ecosystem which surrounds all our SGX cores.
PowerVR Series5XT provides a market leading feature set
Features can make or break a product. Miss out on a key feature required by the latest killer application and your product instantly becomes obsolete and nearly impossible to sell. On the other hand, overload on features and they might go unused resulting in increased costs.
This becomes especially important for SoCs where excess silicon area and (even worse) increased power consumption easily leads to reduced battery life and possibly even heat problems. As an Intellectual Property (IP) provider, Imagination Technologies have invested a lot of time and care into market requirements analysis to ensure that our GPU cores are ‘just right’, not too much and definitely not too little, ensuring that we carefully match market demand.
This is actually a lot more complex than you might think as IP needs to be developed as far ahead of new API standards as possible to allow for design-in time. Flexibility, knowledge and experience are all critical in this process. Time to market is a complex factor in the life of an IP provider as we have to take into account that our GPU IP has to be integrated into an SoC (System on Chip).
This chart shows the typical stages of a product’s design cycle from design and production to shipment
This takes both hardware and software development time, as the SoC then needs to be integrated into a product, which again takes both product hardware and software development time. Ultimately everybody involved in this process makes a profit by shipping the SoC and products in large volume and – if at all possible – for as long as possible, something which depends on the longevity of the architecture.
Imagination cannot just provide a point solution; we need to provide GPU IP that is consistently ahead of its time. By doing this, we can help our partners cover SoC and product development time. We also ensure that both remain relevant across multiple years of shipping in volume. All of this is only possible by delivering a market leading architectural design backed up by a tremendous continuous software development effort and developer support – the latter which I’ll discuss later in this series.
In this section however, I’ll focus on why the feature set choices made for our PowerVR Series5XT products provide a correct balance for system designers. This has been proven not just by the adoption in the Galaxy S4 flagship phone but also by the adoption by numerous other SoC vendors.
Even more importantly, the PowerVR Series5XT GPU has been used in more than 100 different products shipping today – and many more are soon to ship and will continue to be shipped and used by consumers for many years.
Much more than a conformant OpenGL ES 2.0 implementation
Today, industry standardisation of graphics APIs is absolutely critical. It’s simply not realistic to expect software developers to support proprietary APIs. Such an archaic approach would lead to very wide fragmentation of the market making it near impossible for software developers to make a living as they would have to invest very heavily into supporting each and every specific device.
Supporting an industry standard has to be taken seriously and no shortcuts can be taken as again this leads to fragmentation due to unexpected behaviour of the software across different devices. For this reason Imagination Technologies is always focussed on providing full, complete and conformance tested hardware support for industry standards such as the Khronos developed OpenGL ES 2.0 standard – today’s dominant graphics API in the mobile market.
Our PowerVR Series5XT GPU IP does not just implement the baseline minimal OpenGL ES 2.0 specifications; rather we fully and completely support the OpenGL ES 2.0 specifications including all optional components. This approach ensures that developers do not need to have any concerns: whatever feature they opt to use from the standard it will work at full performance on SoCs and products containing our graphics hardware.
The difference between implementing the full OpenGL ES 2.0 standard (PowerVR) and just the basic, minimal specifications (competing GPUs)
For our customers, full support translates to low risk and a future proof design as there is no need to worry about that next killer application which depends on an optional feature.
Competing GPU designs, in house or IP licensed, have failed to recognise this and their architects have opted to save silicon costs by providing an incomplete implementation. As a result, many of those SoCs and Products today have already become obsolete as software developers increasingly tap into ever more advanced graphical features and algorithms.
The Chase demo shown by Unity at GDC 2013 is a perfect example of how forward thinking in designing your GPU IP leads to the best graphics performance on the market:
Optional features fully supported by PowerVR Series5XT include:
- Vertex Texturing which enables displacement mapping style effects (e.g. footsteps in snow) and massive look-up tables
- High Precision support in shaders (support for full 32 bits floating point) which ensures maximal image quality and shading algorithm precision.
Both of these are critical for today’s Retina-like display resolutions as well as ever more advanced shader effects as shown above.
Because SGX implements the full OpenGL ES 2.0 specifications, Imagination’s customers, our customers’ customers as well as end users have the benefit of a feature-complete, future proof product with maximum application compatibility. This ensures a realistic immersive experience for consumers and maximum revenue opportunities for all companies involved.
In the next blog post, I will discuss how and why we’ve chosen to support not just the full OpenGL ES 2.0 specification, but also provide powerful extensions that bring OpenGL ES 3.0 features to current devices. I will also describe our DirectX roadmap and Windows 8 support.
If you have any questions or feedback about Imagination’s graphics IP, please use the comments box below. To keep up to date with the latest developments on PowerVR, follow us on Twitter (@GPUCompute, @PowerVRInsider and @ImaginationPR) and subscribe to our blog feed.
‘Understanding PowerVR’ is an on-going, multi-part series of blog posts from Kristof Beets, Imagination’s Senior Business Development Manager for PowerVR. These articles not only focus on the features that make PowerVR GPUs great, but also provide a detailed look at graphics hardware architectures and software ecosystems in mobile markets.
If you’ve missed any of the posts, here are some backlinks:
- PowerVR GPUs and graphics API standards (part 1)
- PowerVR GPUs and graphics API standards (part 2)
- PowerVR and GPU compute (part 3)
- PowerVR, TBDR and architecture efficiency (part 4)
- Multithreading, multitasking ALUs, the MicroKernel and core scalability (part 5)
- PVRTC, PVRTC2 and texture compression (part 6)
- YUV colour space conversions and the 2D core (part 7)
- PowerVR’s market leading fillrate efficiency (part 8)
- PowerVR’s hardware is nothing without software optimization (part 9)
- The PowerVR Insider ecosystem and final thoughts (part 10)