Server Base System Architecture
The Server Base System Architecture is a hardware system architecture for servers based on 64-bit ARM processors.
Rationale
Historically, ARM-based products have often been tailored for specific applications and power profiles. Variation between ARM-based hardware platforms has been an impediment requiring operating system adjustments for each product.The SBSA seeks to strengthen the ARM ecosystem by specifying a minimal set of standardized features so that an OS built for this standard platform should function correctly without modification on all hardware products compliant with the specification.
Features
- CPU features
- Memory management
- Peripheral access
- Interrupts
- Watchdog
Server Base Boot Requirements
Firmware issues are addressed separately in the Server Base Boot Requirements specification.Platform validation
The Architecture Compliance Suite checks whether an environment is compliant with the SBSA specification, and is provided under an Apache 2 open source license. It is available at https://github.com/ARM-software/sbsa-acs.Compliance levels
The specification defines levels of compliance, with level 0 being the most basic, and successive levels building on prior levels. In the words of the spec, "Unless explicitly stated, all specification items belonging to level N apply to levels greater than N."Level 0, 1, and 2
Levels 0, 1, and 2 have been deprecated and folded into level 3.Level 3
Level 3 contains base-level specifications for:- PE features
- Memory map
- Interrupt controller
- PPI assignments
- MMU behavior
- Clock and timer subsystem
- Wake up semantics
- Power state semantics
- Watchdogs
- Peripheral subsystems