The increasing cost of developing system-on-chip (SoC) devices is driving more importance onto the software. More designers are turning to programmable SoCs which can be used across a range of different applications, but that is driving more emphasis on the software development.

The move was recognised several years ago with processor vendors supplying the software development environment, but this is now moving up to providing more of the application software and application level tools.

New SoC devices, such as Japanese consumer chip maker NEC’s fourth generation EMMA multimedia chip, have over 1.7 million lines of code. That software has to run on several generations of the chip to recoup the investment in such a huge development project.

Even the ‘must have’ toys this Christmas, such as the RoboSapien from Wow Wee, are powered by a 32-bit SoC - with a processor from Cambridge-based ARM - with significant software development.

Now the processor vendor has to provide codecs, networking stacks and Java engines, or at least have a strong ecosystem of suppliers with the available application software. But for the processor vendor this then becomes a balance of commoditisation, where there is little return for the investment in developing the software, little differentiation from other products and brings it into competition with the customer, the SoC designer.

But this raises the question of how much the processor vendor has to invest in application software. Some companies such as MIPS Technologies have partnered closely with software providers such as Dolby. Others, such as UK-based configurable processor developer ARC, have bought software companies such as Russian codec developer Alarity and US multicore start-up Teja Technologies.

That is partly a result of the configurable technology but also more of a focus on the vertical consumer market.

“At the end of the day, it’s the software that makes the difference,” says Carl Schlachte, CEO of ARC. “Our focus on low power consumer electronics means we have to deliver a suite of technologies that allows them to support a range of standards and differentiate at the same time.”

ARC has been developing the codecs to go on its audio and now video subsystems, based around the ARC core with configurable instructions to accelerate the specific applications. While there have been automatically generated software tools to help generate these applications, now ARC has moved to providing more standard cores.

“We have abstracted the range [of products] away from configurability because, from the consumer standpoint, configurable out-of-the-box design at the device level doesn’t matter,” explains Schlachte.

“It’s the ability to deliver a low power MP3 coder design that matters, and we are focussing on the software as that’s the way we can get development times down to four to six months from 18 months. But configurable is definitely not dead – it’s importance has shot up dramatically in providing these different engines quickly,” adds Schlachte.

This is also driven by the fact that much of the SoC development is happening in Taiwan and Asia, and, according to Sclachte, they want the chips out as quickly as possible. “The US is flat and Europe has grown slightly as markets,” says Sclachte.

“It really is becoming more of a software business,” says Jack Browne, vice-president of marketing for the processor division at MIPS Technologies. “Our customers are talking about the system platform to give them a range of IP that they can migrate across several technology nodes so that their software will live across three or four generations of silicon technology.”

Browne says there has been a lot of discussion in the SoC industry about the cost of doing SoC designs.

“At 130nm the cost of software development is roughly equal to the hardware development and today we are talking about 65nm and 45nm and that’s why we are hearing all the SoC vendors talking about platforms – that’s the software environment,” explains Browne.

A typical SoC for a recordable DVD player needs around 25 different audio codecs, he says: “We have 17 of these, half developed by us and half by partners.”

How these are developed depends on the partners and the customers.

“It’s not that one business model fits all, so what we are trying to do is make the technology available pervasively,” says Browne. “For instance Dolby [which includes codec provider Coding Technologies] publish their algorithms and source code so we take that and pre-certify it, while we are able to collaborate with partners such as Fraunhofer so that they provide support.”

Browne says the areas where MIPS provide technology are pretty commoditised. “That’s where it makes sense to do it, as we provide it for less than the cost of the customer doing it themselves,” he explains.

Alongside audio and video, there are increasingly areas such as VoIP and interoperable networking standards, such as MoCa home networking. “But there are extensions to all these areas going on with new standards for voice and video, such as On2 and flash,” Browne says.

Even the ‘hardwired’ video controllers in a device such as Texas Instrument’s (TI) Da Vinci SoC are processors running software. The latest C6467 part uses an ARM9 processor and a DSP core alongside two video and imaging co-processors (VICP) to handle high definition video encoding and decoding.

These VICPs also include ARM9 cores and this programmability is part of the differentiation. “The reason the DSP is so valuable is because of the flexibility in handling multiple types of video with the ability to modify the motion estimation algorithm on the co-processor in real time,” says JB Fowler, SoC product marketing manager for Da Vinci at TI. “This allows you to change the search patterns and the size of the macro blocks so, for example, you could also run a flash-based player with different search windows from H.264.”

But some of the software can be very specific, and ARM has also been working on helping the developers in these more specific areas.

It has teamed up with safety-critical software developer Esterel Technologies to develop a toolchain for safety-critical systems requiring IEC 61508 certification. This combines Esterel’s SCADE Suite and ARM’s RealView Compilation Tools, from modelling and code generation to compiling and debugging, for safety-critical systems in automotive, transportation and industrial control.

The SCADE Suite automatically generates code that is compliant with IEC 61508, as well as the Motor Industry Software Reliability Association (MISRA) rules for software development in the C programming language.

By using SCADE Suite together with RealView, automotive system design engineers will be able to significantly reduce the time it takes to develop software, remove errors, and optimise the speed, memory and code size for SoCs based on the Cortex-M3 and Cortex-R4 processors.