DC-SCM compatible open source BMC hardware platform


Topics: Open hardware, Open cloud systems, Open FPGA

Open source software is omnipresent in the server and cloud world, with open source operating systems, container runtimes, as well as frameworks for device management, monitoring and data pipelining, workload execution etc. This has given the rise to impressive successes in the SaaS space, where useful products can be rapidly created from open source components.

Following this clear pattern from the software world, increasingly cloud providers and users are looking at building their servers using open source hardware as well. Antmicro has been supporting its customers (including hyperscalers like Google) in creating useful server-facing open source hardware such as Scalenode or ARVSOM.

Most recently, in one of our projects with Google we have developed an open source hardware FPGA-based Baseboard Management Controller (BMC) platform compliant with the new DC-SCM specification to help increase the security, configurability and flexibility of server management and monitoring infrastructure, which was since then adopted by the LibreBMC workgroup as the base hardware platform.

Open-hardware DC-SCM Artix7 board

The DC-SCM spec

Developed by the Open Compute Project, the Datacenter-ready Secure Control Module (DC-SCM) specification aims to move common server management, security and control features from a typical motherboard into a module designed in one of the two form factors featured in the specification (Horizontal or Vertical), which can be used across various datacenter platforms.

Currently being adopted by the likes of Google, Microsoft, Facebook and IBM, the spec will let leading players in the industry share costs, risks and increase reuse. Coupled with a fully open source implementation based on our open source FPGA-based modules, it has a chance to redefine the way board management is done. Basing the module on popular, inexpensive FPGA platforms will not only allow for more configurability and a tighter integration between hardware and software, but also tap into the momentum behind the broader open source hardware community via groups like CHIPS Alliance, OpenPOWER and RISC-V.

The hardware

We have developed two implementations of our DC-SCM-compatible BMC. Both designs meet the Open Compute Project specification for a Horizontal Form Factor 90x120 mm DC-SCM.

The BMCs role is central to the server’s faultless operation: it is responsible for monitoring the system and preventing and mitigating failures, acting as an external watchdog.

To be able to provide this functionality, according to the requirements, the module offers a feature-packed Secure Control Interface for communication with the host platform, including:

  • PCI Express
  • USB
  • QSPI
  • NCSI
  • multiple I2C, I3C and UART channels.

The unique property of our implementation of the standard is merging DC-SCM’s central Baseband Management Controller and programmable SCM CPLD block into one powerful FPGA. This solution was chosen having in mind flexibility of the design, allowing remote updates of DC-SCM peripherals, and most notably, placing OpenPOWER or RISC-V IP cores as central processing units of the module.

One of our designs is based on the Xilinx Artix-7 FPGA, whereas the other one features a Lattice ECP5 FPGA - both low-cost and open source friendly FPGAs supported by the open source SymbiFlow FPGA toolchain project we are heavily involved with.

The FPGA is complemented by 512MB of DDR3 memory, 16GB of eMMC flash, as well as a dedicated Gigabit-Ethernet interface. To ensure the security of the Datacenter Control Module, external cryptographic modules: Root of Trust (RoT) and Trusted Platform Module (TPM) can be connected. This will allow future integration with e.g. open hardware Root of Trust projects such as OpenTitan (which we are also supporting with our open source developments) and implementing various boot flow and authentication approaches.

Use in LibreBMC / OpenPOWER

Open source, configurable hardware platforms based on FPGA, open tooling and standards can make BMC more flexible for tomorrow’s challenges. Antmicro’s DC-SCM boards have been adopted by the LibreBMC Workgroup, operating under the umbrella of the OpenPOWER Foundation, in a push to build a complete, fully transparent BMC solution. The workgroup, with participation from IBM, Google and Antmicro, among others, will be involved with creating FPGA gateware and software needed to make the hardware fully operational in real-world server solutions. Variants involving both Linux (in its default open source server-oriented distribution, OpenBMC) and Zephyr RTOS, as well as with both POWER and RISC-V cores are planned and thanks to the flexibility of FPGA all of those options will be just one gateware update away. Of course, both the gateware and software will be open source as well.

OpenPOWER Foundation logo

Open cloud and edge/cloud hybrid systems by Antmicro

At Antmicro, we strongly believe crucial technology should be open. With a DC-SCM spec-compatible OpenBMC platform by Antmicro and our broader expertise in server hardware and cloud infrastructure, you can take things further and hire us to build scalable cloud or hybrid edge/cloud systems dedicated to both your use case, and keeping things safe and open. Find out more at contact@antmicro.com.

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