Even though Apple has been shipping a 64-bit capable SoC since the release of the A7 part in September of 2013, the Android market has yet to see its first consumer 64-bit SoC release. That is about to change as we progress through the rest of 2014 and ARM is making sure that major software developers have the tools they need to be ready for the architecture shift. That help is will come in the form of the Juno ARM Development Platform (ADP) and 64-bit ready software stack.
Apple's A7 is the first core to implement ARMv8 but companies like Qualcomm, NVIDIA and course ARM have their own cores based on the 64-bit architecture. Much like we saw the with the 64-bit transition in the x86 ecosystem, ARMv8 will improve access to large datasets, will result in gains in performance thanks to increased register sizes, larger virtual address spaces above 4GB and more. ARM also improved performance of NEON (SIMD) and cryptography support while they were in there fixing up the house.
The Juno platform is the first 64-bit development platform to come directly from ARM and combines a host of components to create a reference hardware design for integrators and developers to target moving forward. Featuring a test chip built around Cortex-A57 (dual core), Cortex-A53 (quad core) and Mali-T624 (quad core), Juno allows software to target 64-bit development immediately without waiting for other SoC vendors to have product silicon ready. The hardware configuration implements big.LITTLE, OpenGL ES3.0 support, thermal and power management, Secure OS capability and more. In theory, ARM has built a platform that will be very similar to SoCs built by its partners in the coming months.
ARM isn't quite talking about the specific availability of the Juno platform, but for the target audience ARM should be able to provide the amount of development platforms necessary. Juno enables software development for 64-bit kernels, drivers, and tools and virtual machine hypervisors but it's not necessarily going to help developers writing generic applications. Think of Juno as the development platform for the low level designers and coders, not those that are migrating Facebook or Flappy Bird to your next smartphone.
The Juno platform helps ARM in a couple of specific ways. From a software perspective, it creates common foundation for the ARMv8 ecosystem and allows developer access to silicon before ARM's partners have prepared their own platforms. ARM claims that Juno is a fairly "neutral" platform so software developers won't feel like they are being funneled in one direction. I'd be curious what ARM's partners actually think about that though with the inclusion of Mali graphics, a product that ARM is definitely trying to promote in a competitive market.
Though the primary focus might be software, hardware partners will be able to benefit from Juno. On this board they will find the entire ARMv8 IP portfolio tested up to modern silicon. This should enable hardware vendors to see A57 and A53 working, in action and with the added benefit of a full big.LITTLE implementation. The hope is that this will dramatically accelerate the time to market for future 64-bit ARM designs.
The diagram above shows the full break down of the Juno SoC as well as some of the external connectivity on the board itself. The memory system is built around 8GB of DDR3 running at 12.8 GB/s and the is extensible through the PCI Express slots and the FPGA options.
Of course hardware is only half the story – today Linaro is releasing a 64-bit port of the Android Open Source Project (AOSP) that will run on Juno. That, along with the Linux kernel v3.14 with ARMv8-A support should give developers the tools needed to write the applications, middleware and kernels for future hardware. Also worth noting on June 25th at Google I/O was the announcement of developer access coming for Android L. This build will support ARMv8-A as well.
The switch to 64-bit technology on ARM devices isn't going to happen overnight but ARM and its partners have put together a collective ecosystem that will allow the software and hardware developers to make transition as quick and, most importantly, as painless as possible. With outside pressure pushing on ARM and its low power processor designs, it is taking more of its fate in its own hands, pushing the 64-bit transition forward at an accelerated pace. This helps ARM in the mobile space, the consumer space as well as the enterprise markets, a key market for SoC growth.