Samsung Announces A15/Mali-T604 Based Exynos 5 Dual

Yesterday Samsung officially announced what we all knew was coming: the Exynos 5 Dual. Due to start shipping sometime between the end of the year and early next year, the Exynos 5 Dual combines two ARM Cortex A15s with an ARM Mali-T604 GPU on a single 32nm HK+MG die from Samsung.

The CPU

Samsung's Exynos 5 Dual integrates two ARM Cortex A15 cores running at up to 1.7GHz with a shared 1MB L2 cache. The A15 is a 3-issue, Out of Order ARMv7 architecture with advanced SIMDv2 support. The memory interface side of the A15 should be much improved compared to the A9. The wider front end, beefed up internal data structures and higher clock speed will all contribute to a significant performance improvement over Cortex A9 based designs. It's even likely that we'll see A15 give Krait a run for its money, although Qualcomm is expected to introduce another revision of the Krait architecture sometime next year to improve IPC and overall performance. The A15 is also found in TI's OMAP 5. It will likely be used in NVIDIA's forthcoming Wayne SoC, as well as the Apple SoC driving the next iPad in 2013.

The Memory Interface

With its A5X Apple introduced the first mobile SoC with a 128-bit wide memory controller. A look at the A5X die reveals four 32-bit LPDDR2 memory partitions. The four memory channels are routed to two LPDDR2 packages each with two 32-bit interfaces (and two DRAM die) per package. Samsung, having manufactured the A5X for Apple, learned from the best. The Exynos 5 Dual is referred to as having a two-port LPDDR3-800 controller delivering 12.8GB/s of memory bandwidth. Samsung isn't specific about the width of each port, but the memory bandwidth figure tells us all we need to know. Each port is either 64-bits wide or the actual LPDDR3 data rate is 1600MHz. If I had to guess I would assume the latter. I don't know that the 32nm Exynos 5 Dual die is big eough to accommodate a 128-bit memory interface (you need to carefully balance IO pins with die size to avoid ballooning your die to accommodate a really wide interface). Either way the Exynos 5 Dual will equal Apple's A5X in terms of memory bandwidth.

TI's OMAP 5 features a 2x32-bit LPDDR2/DDR3 interface and is currently rated for data rates of up to 1066MHz, although I suspect it wouldn't be too much of a stretch to get DDR3-1600 memory working with the SoC. Qualcomm's Krait based Snapdragon S4 also has a dual-channel LPDDR2 interface, although once again there's no word on what the upper bound will be for supported memory frequencies.

The GPU

Samsung's fondness of ARM designed GPU cores continues with the Exynos 5 Dual. The ARM Mali-T604 makes its debut in the Exynos 5 Dual in quad-core form. Mali-T604 is ARM's first unified shader architecture GPU, which should help it deliver more balanced performance regardless of workload (the current Mali-400 falls short in the latest polygon heavy workloads thanks to its unbalanced pixel/vertex shader count). Each core has been improved (there are now two ALU pipes per core vs. one in the Mali-400) and core clocks should be much higher thanks to Samsung's 32nm LP process. Add in gobs of memory bandwidth and you've got a recipe for a pretty powerful GPU. Depending on clock speeds I would expect peak performance north of the PowerVR SGX 543MP2, although I'm not sure if we'll see performance greater than the 543MP4. The Mali-T604 also brings expanded API support including DirectX 11 (feature level 9_3 though, not 11_0).

Video encode and decode are rated at 1080p60.

The Rest

To complete the package Samsung integrates USB 3.0, SATA 3, HDMI 1.4 and eDP interfaces into the Exynos 5 Dual. The latter supports display resolutions up to 2560 x 1600. The complete package is the new face of a modern day mobile system on a chip.

Samsung remains very aggressive on the SoC front. The real trick will be whether or not Samsung can convince other smartphone and tablet vendors (not just Samsung Mobile) to use its solution instead of something from TI, NVIDIA or Qualcomm. As long as Samsung Mobile ships successful devices the Samsung Semiconductor folks don't have to worry too much about growing marketshare, but long term it has to be a concern.