Adaptive Voltage Scaling with In-Situ Detectors in Commercial FPGAs

Energy proportional computing with OpenCL on a FPGA-based overlay architecture

“…The energy proportional system consists of in-situ detectors and additional hardware and software to support adaptive voltage and frequency scaling (AVFS). The in-situ detectors [11] are used to protect critical paths in order to reliably operate the design across a range of frequencies and voltages whereas AVFS is used together with system characterization to influence the voltage and frequency on the fly in closedloop configuration. The in-situ detectors have been introduced in the design netlist using the post place & route timing information of the system.…”

“…The in-situ detectors have been introduced in the design netlist using the post place & route timing information of the system. The core of the flow is the Elongate tool [11] that transforms the original design netlist into a new netlist with identical functionality and additional power management IP and in-situ detectors. Fig.…”

“…We have used the ZYNQ-based ZC702 Evaluation Board running UBUNTU Linux OS. The DVS (Dynamic Voltage Scaling) unit originally presented in [11] has been removed since the voltage scaling is done by the ARM directly using the I2C controller shown to the right of the figure. The DFS (Dynamic Frequency Scaler) shows the addition of a PLL whose clock input is connected to the clock output of the MMCM (Mixed Mode Clock Manager).…”

Run-time power and performance scaling with CPU-FPGA hybrids

“…In ASICS lowering the supply voltage reduces both dynamic and static power at the cost of increased circuit delay and a similar approach can be used with FPGAs as well [2]. Voltage scaling is often combined with frequency scaling in order to compensate for the variation of circuit delay.…”

“…However, worst case variability is rarely the case. Previous work [2] has validated an approach called Elongate based on in-situ detectors that uses the logic available in the FPGA slices of Xilinx 65 nm Virtex-5 devices to adjust voltage and frequency.…”