Copyright (c) 2011-2023, Arm Limited. All rights reserved.

[1] Power Control System Architecture - DEN0050C (Please contact Arm directly to obtain a copy of this document)

[2] System Control and Management Interface - DEN0056A

[3] Power Policy Unit - DEN0051C (Please contact Arm directly to obtain a copy of this document)

[4] System Guidance

There is a strong trend in the industry to provide microcontrollers in systems to abstract various power, or other system management tasks, away from Application Processors (APs). The Power Control System Architecture (PCSA) [1] describes how systems can be built following this approach.

The PCSA defines the concept of the System Control Processor (SCP), a dedicated processor that is used to abstract power and system management tasks away from application processors.

Similar to the SCP, the Manageability Control Processor (MCP) follows the same approach with the goal of providing a management entry-point to the System on Chip (SoC) where manageability is required, such as on a SoC targeting servers.

SCP-firmware provides a software reference implementation for the System Control Processor (SCP) and Manageability Control Processor (MCP) components found in several Arm Compute Sub-Systems.

• Initialization of the system to enable application core boot
• Runtime services:
  • Power domain management
  • System power management
  • Performance domain management (Dynamic Voltage and Frequency Scaling)
  • Clock management
  • Sensor management
  • Reset domain management
  • Voltage domain management
• System Control and Management Interface (SCMI, platform-side)
• Support for the GNU Arm Embedded, Arm Compiler 6 and LLVM toolchains
• Support for platforms with several control processors
• Interactive debugging (with Command Line Interface)

Various builds of the release have been tested on the following ARM Fixed Virtual Platforms (FVPs or boards where possible):

• System Guidance for Mobile platform SGM-775 (Version 11.3 Build 42)
• System Guidance for Infrastruture SGI-575 (Version 11.3 Build 42)
• Neoverse N1 reference design (Version 11.6 Build 45)
• System Guidance for Mobile platform SGM-776 (Version 11.6 Build 45)
• Juno reference design (Please contact Arm directly to obtain the Juno FVP)
• RD-N1-Edge Dual-Chip reference design (Please contact Arm directly to obtain the RdN1EdgeX2 FVP)
• RD-V1 reference design (Please contact Arm directly to obtain the RD_V1 FVP)
• RD-V1-MC reference design (Please contact Arm directly to obtain the RD_V1_Multichip FVP)
• Renesas R-Car platform
• Total Compute (tc0) platform (Please contact Arm directly to obtain the TC0 FVP)
• Morello (Please see Arm's Ecosystem FVPs Developer page)
• Total Compute (tc1) platform (Please contact Arm directly to obtain the TC1 FVP)

The software is provided under a BSD-3-Clause license.

The license for CMock can be found in contrib/cmock/git/LICENSE.txt.

The license for unity framework can be found in contrib/cmock/git/vendor/unity/LICENSE.txt.

See user_guide.md for instructions on how to get, install, build and use SCP-firmware on supported Arm platforms.

SCP-firmware now supports building with CMake. See doc/cmake_readme.md for details.

Arm welcomes any feedback on SCP-firmware. Please contact the maintainers (see maintainers.md).

To request support please contact Arm by email at support@arm.com. Arm licensees may also contact Arm via their partner managers.

To report any security issue please contact Arm by email at arm-security@arm.com.

More details can be found at Arm Developer website.