Glossary of Terms¶
Advanced Configuration and Power Interface
ACRN is a flexible, lightweight reference hypervisor, built with real-time and safety-criticality in mind, optimized to streamline embedded development through an open source platform.
A user mode device model application running in Service OS to provide device emulations in ACRN hypervisor.
Intel GVT-g technology for ACRN.
CPU-visible graphics memory
Application Program Interface: A defined set of routines and protocols for building application software.
Apollo Lake platform
Broadwell, Intel 5th-generation CPU platform
Basic Input/Output System.
- Dom0 i915
The Intel Graphics driver running in Domain 0
GPU’s ExecList submission port
Global Graphic Translation Table. The virtual address page table used by a GPU to reference system memory.
Graphics Memory Address
Graphics Processing Unit
Graphic Translation Table
Graphic Translation Table Memory Map Address
Graphics Virtual Technology. GVT-g core device model module up-streamed to the Linux kernel.
Virtual dedicated graphics acceleration (one VM to one physical GPU)
Virtual graphics processing unit (multiple VMs to one physical GPU)
Virtual shared graphics acceleration (multiple VMs to one physical GPU)
- Hidden GM
Hidden or High graphics memory, not visible to the CPU.
- High GM
See Hidden GM
Hypervisor Service Module
- Hybrid Mode
One of three operation modes (hybrid, partition, sharing) that ACRN supports. In this mixed mode, physical hardware resources can be both partitioned to individual user VMs and shared across user VMs.
The Intel Graphics driver
Interrupt Descriptor Table: a data structure used by the x86 architecture to implement an interrupt vector table. The IDT is used to determine the correct response to interrupts and exceptions.
Interrupt Service Routine: Also known as an interrupt handler, an ISR is a callback function whose execution is triggered by a hardware interrupt (or software interrupt instructions) and is used to handle high-priority conditions that require interrupting the current code executing on the processor.
- low GM
Operating System Power Management
- Partition Mode
One of three operation modes (partition, sharing, hybrid) that ACRN supports. Physical hardware resources are partitioned to individual user VMs.
- Passthrough Device
Physical devices (typically PCI) exclusively assigned to a guest. In the Project ACRN architecture, passthrough devices are owned by the foreground OS.
Peripheral Component Interface.
Page Directory Entry
- Post-launched VM
Post-Launched VMs are launched and configured by the Service VM. (See Pre-launched VM)
- Pre-launched VM
Pre-launched VMs are started by the ACRN hypervisor before the Service VM is launched. (See Post-launched VM)
Page Table Entry
Para-virtualization (See https://en.wikipedia.org/wiki/Paravirtualization)
Para-Virtualization Information Page, a MMIO range used to implement para-virtualization
Quick EMUlator. Machine emulator running in user space.
Intel Resource Director Technology (Intel RDT) provides a set of monitoring and allocation capabilities to control resources such as Cache and Memory. ACRN supports Cache Allocation Technology (CAT) and Memory Bandwidth Allocation (MBA).
Rear Seat Entertainment
Real-time VM. A specially-designed VM that can run hard real-time or soft real-time workloads (or applications) much more efficiently than the typical User VM through the use of a passthrough interrupt controller, polling-mode Virtio, Intel RDT allocation features (CAT, MBA), and I/O prioritization. RTVMs are typically a Pre-launched VM. A non-Safety VM with real-time requirements is a Post-launched VM.
- Safety VM
A special VM with dedicated hardware resources, running in partition mode, and providing overall system health-monitoring functionality. Currently, a Safety VM is always a pre-launched User VM.
Software Defined Cockpit
- Service OS
Obsolete, see Service VM
- Service VM
The Service VM is generally the first VM launched by ACRN and can access hardware resources directly by running native drivers and provides device sharing services to User VMs via the Device Model.
- Sharing Mode
One of three operation modes (sharing, hybrid, partition) that ACRN supports. Most of the physical hardware resources are shared across user VMs.
Obsolete, see Service VM
Unified Extensible Firmare Interface. UEFI replaces the traditional BIOS on PCs, while also providing BIOS emulation for backward compatibility. UEFI can run in 32-bit or 64-bit mode and, more important, support Secure Boot, checking the OS validity to ensure no malware has tampered with the boot process.
Obsolete, see User VM
- User OS
Obsolete, see User VM
- User VM
User Virtual Machine.
Virtual GPU Instance, created by GVT-g and used by a VM
Back-End, VirtIO framework provides front-end driver and back-end driver for IO mediators, developer has habit of using Shorthand. So they say Virtio-BE and Virtio-FE
Front-End, VirtIO framework provides front-end driver and back-end driver for IO mediators, developer has habit of using Shorthand. So they say Virtio-BE and Virtio-FE
Virtual Machine, a guest OS running environment
Virtual Machine Monitor
Virtual Machine Extension
Intel Virtualization Technology
Virtualization Technology for Directed I/O