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.

At this point in time, this daemon targets Lewisburg based, dual socket x86 server platforms, such as S2600WFT. It is likely that other platforms will work as well.

Because this relies on the hardware passthrough support in the AST2500 to function, it requires a few patches to work correctly.

This patch adds support to UBOOT to keep the passthrough enabled https://github.com/Intel-BMC/openbmc/blob/intel/meta-openbmc-mods/meta-common/ recipes-bsp/u-boot/files/0005-enable-passthrough-in-uboot.patch

The DTS file for your platform will need the following GPIO definitions RESET_BUTTON RESET_OUT POWER_BUTTON POWER_OUT

On an aspeed, these are generally connected to E0, E1, E2, and E3 respecitvely. An example of this is available in the s2600WF config.

This patch allows the passthrough to be reenabled to the default condition when the appropriate pin is released. This allows power control to take control when needed by a user power action, but leave the hardware in control a majority of the time, reducing the possibilty of bricking a system due to a failed BMC.

https://github.com/Intel-BMC/openbmc/blob/intel/meta-openbmc-mods/meta-ast2500/recipes-kernel/linux/linux-aspeed/0002-Enable-pass-through-on-GPIOE1-and-GPIOE3-free.patch https://github.com/Intel-BMC/openbmc/blob/intel/meta-openbmc-mods/meta-ast2500/recipes-kernel/linux/linux-aspeed/0003-Enable-GPIOE0-and-GPIOE2-pass-through-by-default.patch https://github.com/Intel-BMC/openbmc/blob/intel/meta-openbmc-mods/meta-ast2500/recipes-kernel/linux/linux-aspeed/0006-Allow-monitoring-of-power-control-input-GPIOs.patch

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.