Power Management Software Architecture - 2020.2 English

Zynq UltraScale+ MPSoC Software Developer Guide (UG1137)

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2020.2 English

The Zynq UltraScale+ MPSoC architecture employs a dedicated programmable unit (PMU) that controls the power-up, power-down, monitor, and wakeup mechanisms of all system resources. The customer benefits from a system that is better equipped on handling power management administration for a multiprocessor heterogeneous system. However, it is inherently more complex. The goal of the Power Management Framework is to abstract this complexity, exposing only the APIs you need to be aware of to meet your power budget goal.

Figure 1. Power Management Framework

The intention of the EEMI is to provide a common API that allows all software components to power manage cores and peripherals. At a high level, EEMI allows you to specify a high-level power management goal such as suspending a complex processor cluster or just a single core. The underlying implementation is then free to autonomously implement an optimal power-saving approach.

The Linux device tree provides a common description format for each device and its power characteristics. Linux also provides basic power management capabilities such as idle, hotplug, suspend, resume, and wakeup. The kernel relies on the underlining APIs to execute power management decisions.

You can also create your own power management applications using the XilPM library, which provides access to more than 24 APIs.