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gerrit.openbmc.org / openbmc / x86-power-control / refs/heads/master
commitf0b0fbddc050a87a39ae3f5a42aa7333290adfbf[log] [tgz]
authorNathan Jian <Hank.Jian@quantatw.com>Wed Jan 21 12:50:43 2026 +0000
committerNathan Jian <Hank.Jian@quantatw.com>Thu Jan 29 10:30:13 2026 +0800
treebec557f9e462a15f7a6c50cc2cb56d6803e92704
parent9cf51d8d8745b1fb6b14198b0004a1507d00e8ca [diff]
power-control: Use constexpr string_view

Convert getPowerStateName() and getEventName() to return constexpr
std::string_view instead of std::string to avoid heap allocations.

Update logStateTransition() and logEvent() to handle unknown enum
values by logging an error with the integer value for debugging.

Tested:
- Build verification: Compiled successfully with no warnings
- Power state transitions on AST2600: All states logged correctly

Change-Id: I644dd2e6ac6502d8a5460be393997a37e8da0134
Signed-off-by: Nathan Jian <Hank.Jian@quantatw.com>
1 file changed
tree: bec557f9e462a15f7a6c50cc2cb56d6803e92704
  1. config/
  2. service_files/
  3. src/
  4. subprojects/
  5. .clang-format
  6. .clang-tidy
  7. .gitignore
  8. LICENSE
  9. meson.build
  10. meson.options
  11. OWNERS
  12. README.md
README.md

X86 power control

This repository contains an OpenBMC compliant implementation of power control for x86 servers. It relies on a number of features to do its job. It has several intentional design goals.

  1. The BMC should maintain the Host state machine internally, and be able to track state changes.
  2. The implementation should either give the requested power control result, or should log an error on the failure it detected.
  3. The BMC should support all the common operations, hard power on/off/cycle, soft power on/off/cycle.

This daemon has been successfully used on a variety of server platforms; it should be able to support platforms with power control GPIOs similar to those in its config file.

x86-power-control uses default json file (power-config-host0.json) for GPIO configuration. However this can be customized by producing your own power-config-host0.json file.

Signal Definitions

Definitions can be configured by two type: GPIO and DBUS

GPIO

For the platform having direct GPIO access can use the type GPIO and define like below.

{
  "Name": "PostComplete",
  "LineName": "POST_COMPLETE",
  "Type": "GPIO"
}

DBUS

For the platform not having direct GPIO access can use dbus based event monitor by using the type DBUS.

{
  "Name": "PowerButton",
  "DbusName": "xyz.openbmc_project.Chassis.Event",
  "Path": "/xyz/openbmc_project/Chassis/Event",
  "Interface": "xyz.openbmc_project.Chassis.Event",
  "Property": "PowerButton_Host1",
  "Type": "DBUS"
}

x86-power-control will monitor the property change from the given DbusName and take appropriate action. *define Property as a bool variable.

Caveats: This implementation does not currently implement the common targets that other implementations do. There were several attempts to, but all ended in timing issues and boot inconsistencies during stress operations.

Build Options

chassis-system-reset

Enable chassis system power reset to allow removing power and restoring back.

use-plt-rst

The POST Complete GPIO is usually held asserted by BIOS after POST complete and de-asserts on reset. This de-assert behavior is currently used to detect warm resets.

Some systems are adding support for a PLT_RST eSPI signal that can be used to more accurately detect warm resets. When this option is enabled, x86-power-control will use PLT_RST to detect warm resets instead of POST Complete.

See https://github.com/Intel-BMC/host-misc-comm-manager for implementation example.