Intel PECI Submitted As Part Of Char/Misc Changes For Linux 5.18

After being years in development, the Intel PECI subsystem is landing for the Linux 5.18 kernel.

Intel's Platform Environment Control Interface (PECI) with this Linux kernel support is for exposing the PECI interface between the CPU and baseboard management controllers (BMCs) and other platform management devices on Intel server platforms. This Intel PECI Linux code supports Xeon E5/E7 v3, Xeon E5/E7 v4, and Xeon Scalable CPUs.

As part of the PECI subsystem bring-up for Linux 5.18, there is the core infrastructure, an ASpeed controller driver for use with AST2400/AST2500/AST2600 BMC SoCs, and CPU and memory module temperature sensor drivers. The peci-cputemp driver is able to expose the current die and DTS temperatures, fan temperature target, the throttle temperature, and the maximum junction temperature. The peci-dimmtemp driver exposes the temperature sensor on DIMM readings that are accessible via PECI.

This PECI addition to the mainline Linux kernel will be principally useful when building a Linux kernel for BMCs on Intel platforms such as with OpenBMC.

The PECI code was sent in today as part of the char/misc changes for the Linux 5.18 merge window. This pull also has various updates for the Intel-owned Habana Labs driver code for these AI accelerators.

On the other side of the table, Linux 5.18 is also adding the AMD HSMP driver for the Host System Management Port on EPYC server platforms.