Linux power management system architecture and drive (1)-Linux Power Management Global Architecture, system architecture-linux

Linux power management system architecture and drive (1)-Linux Power Management Global Architecture, system architecture-linux
1. Global Linux Power Management Architecture

Linux power management is very complex, involving system-level standby, frequency and voltage conversion, processing when the system is idle, support for system standby by each device driver, and power management when each device is running, it can be said that it is closely related to every device driver in the system.

Power management is very important for consumer electronic products. Therefore, this part of work usually occupies a considerable proportion in the development cycle. Figure 1 shows the overall architecture of Linux kernel power management. It can be summarized into the following categories:

1. CPU runs according to the system load for dynamic voltage and frequency conversion CPUFreq

2. When the system is idle, the CPU uses the CPU idle in the low-power mode.

3. Support for hot swapping of CPU in multi-core systems

4. The PM QoS requested by the system and devices for special latency requirements will apply to the specific CPUIdle policy.

5. A series of entry functions of the device driver for the system Suspend to RAM/Disk

6. the SoC enters the suspend status and the SDRAM self-Refresh entry.

7. The runtime (runtime) Dynamic Power Management of the device. The device is dynamically switched according to the usage.

8. Underlying clock, voltage regulator, frequency/voltmeter (OPP module completed) support, may be used by various driving subsystems

Figure 1 Linux Power Management System Architecture