About

This project aims to implement and upstream the MM service group based on MPXY SBI extension and RPMI protocol in EDK2.  This project helps the PoC project EDK2_00_02 - StandaloneMmPkg (PoC) and let it use the spec defined SBI interface.

Latest update (22-June-2025): Based on latest discussions, we will have 2 separate data paths to enable MM properly. 1. Communicate with m-mode over MPXY (using MM RPMI API). Have a monitor like code in OpenSBI to forward MM data packets to STMM using RPMI Req-Fwd APIs.

Project Scope and Timelines

The MM service group implementation includes.

• Leverage the SBI MPXY extension and RPMI protocol, which carries the RPMI message in EDK2

• Put MM inter-domain messaging payload in shared memory in EDK2

• Add an MM Service in RPMI with APIs:

  • MM_VERSION

  • MM_COMMUNICATE

  • MM_COMPLETE

Components and Repos.

Baseline code (RPMI PoC)

^{OpenSBI :} https://github.com/cap2k4-rivos/opensbi/tree/dev/cap2k4/MultiChannelV2

^{EDK2 :} https://github.com/cap2k4-rivos/edk2-staging/tree/dev/cap2k4/multiChannel

Stakeholders and Partners

• RISE

  • Dhaval Sharma <dhaval@rivosinc.com>

  • Akshay Behl <cap2k4@rivosinc.com>

  • Intel: Yong Li <yong.li@intel.com>

Dependencies

Here are the links to the draft specifications for RPMI and MPXY which were shared in the past on the riscv org mailing list for review.
RPMI: https://github.com/riscv-non-isa/riscv-rpmi
MPXY: https://lists.riscv.org/g/tech-prs/message/948

Measure of Success

Code upstream to EDK2 and OpenSBI

RISE Requirements

None,

Status

Updates

Jul 3, 2025 

1. Communicate with m-mode over MPXY (using MM RPMI API). Have a monitor like code in OpenSBI to forward MM data packets to STMM using RPMI Req-Fwd APIs. (In development, OpenSBI part works but not yet ready for upstream).

2. Currently a shared buffer between Non Secure(UPL) and Secure Mode(STMM) is setup for data transfer between them.

Jul 11, 2024 

Rebased code with the latest RPMI PoC

https://github.com/yli147/edk2/tree/dev-standalonemm-mpxy-v3

Mar 6, 2024 

Pending on RPMI spec ratification, will do the code rebase once spec has been ratified