# Linux Power Management - ACPI S-States

[TOC]

## Tooling

### `fwts`

The `fwts` tool on Linux can be used to test the firmware behaviors. One of those behaviors are whether Linux function normally on various ACPI states. The [*Firmware Test Suite (fwts)*](https://wiki.ubuntu.com/FirmwareTestSuite/Reference) on Ubuntu wiki contains descriptions for usage of `fwts`.

Notably, the [`s3`](https://wiki.ubuntu.com/FirmwareTestSuite/Reference/s3) option can put the device into ACPI S3 state, with various options available.

## References

### [Arch4001 07 Power Transition 01 Intro 01 Intr](https://youtu.be/YZ_1Ec_zBYw)

{%youtube YZ_1Ec_zBYw %}

### [Computer Architecture: CPU ACPI Power Management lecture 1](https://youtu.be/JJOrrF41wP8)

{%youtube JJOrrF41wP8 %}

### [Improving monitoring of power saving states - Mr Stanislaw Kardach (Google), Sven van Ashbrook](https://youtu.be/VSfkQ9DcPqI)

{%youtube VSfkQ9DcPqI %}