Linux power Management system architecture and drivers (1)-linux Power Management Global Architecture

1. Linux Power Management Global architecture

Linux power management is very complex, involving system-level standby, frequency-voltage transformation, System idle processing, and each device driver support for system standby and runtime power management for each device, which can be say and every device driver in the system.

Power management is very important for consumer electronics products. Therefore, this part of the work often occupies a considerable proportion in the development cycle, and figure 1 presents the overall architecture of Linux kernel power management. It can be summed up in the following categories:

1. Cpufreq of dynamic voltage and frequency conversion of CPU at runtime according to system load

2. The CPU Cpuidle in low-power mode based on idle conditions when the system is idle

3. CPU hot-swap support for multicore systems

4. PM QoS applied to systems and equipment for delayed special requirements, which will act on the specific strategy of Cpuidle

5. Device driver A series of entry functions for system suspend to Ram/disk

6. Soc enters suspend state, SDRAM self-refresh entrance

7. Runtime (runtime) dynamic power management, dynamic switching of equipment according to the use of the device

8. The underlying clock, voltage regulator, frequency/voltmeter (OPP module complete) support, each drive subsystem may use

Figure 1 Linux Power Management system architecture

Linux power Management system architecture and drivers (1)-linux Power Management Global Architecture