Freescale Adds ARM to QorIQJune 21, 2012
Author: Tom R. Halfhill
Some future QorIQ chips will use ARM CPUs instead of Freescale's PowerPC cores, the company announced at its recent technology forum. Although the ARM-based chips will be built in the same 28nm technology as today's QorIQ T-series, they herald a new product generation that includes a revamped chip-level architecture. That architecture, dubbed Layerscape, is the cornerstone of Freescale's post-2013 QorIQ strategy.
Layerscape divides the chip into three logical partitions: a general-purpose processing layer (the CPUs), an acceleration layer (packet-processing engines), and a packet-I/O layer. This stratification is not radically different from QorIQ today, but some chips will have a new packet-processing core, application programming will be more abstract, packet processing will be more buffered from the wire-speed I/O, and the CPU layer will accommodate either ARM CPUs or Freescale's usual Power cores. In addition, Layerscape extends virtualization, allowing better resource partitioning among virtual machines.
The first two ARM-based QorIQ processors -- the LS1 and LS2 -- embody the entry-level side of Freescale's Layerscape strategy. The LS1 will use the ARM Cortex-A7 CPU; it will include devices that consume less than 3W (estimated TDP) at 1.2GHz and that sell for less than $10 in volume. The LS2 will use the more powerful Cortex-A15 CPU and consume less than 5.5W (estimated TDP) at 1.5GHz. These chips will be pin and software compatible and are scheduled to sample in 2H13, with production likely in 2H14.
Never has Freescale offered QorIQ processors at such a low price -- at least a few dollars less than our estimated price for the least-expensive P1-series chip. Although the company could probably hit the same price and power-consumption targets using a PowerPC design, some customers in the low-end market want ARM compatibility. Freescale says it has no plans to replace Power CPUs with ARM CPUs in all QorIQ chips, however.
Note that ARM is already pervasive throughout other Freescale product lines: Kinetis microcontrollers, Vybrid industrial/automotive SoCs, and i.MX application processors. In that context, adding ARM to the QorIQ family is not a drastic departure. Freescale customers will get new CPU options without switching chip vendors, and next-generation QorIQ processors will span a greater range of performance, power consumption, and cost than any competing product line. For ARM, it's another step toward dominating 32-bit embedded processing.