.. _glossary: Glossary of Terms ################# .. glossary:: :sorted: ACPI Advanced Configuration and Power Interface ACRN 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. AcrnGT Intel GVT-g technology for ACRN. ACRN-DM A user mode device model application running in Service OS to provide device emulations in ACRN hypervisor. aperture CPU-visible graphics memory low GM see :term:`aperture` API Application Program Interface: A defined set of routines and protocols for building application software. APL Apollo Lake platform BDW Broadwell, Intel 5th-generation CPU platform BIOS Basic Input/Output System. Dom0 i915 The Intel Graphics driver running in Domain 0 ELSP GPU's ExecList submission port GGTT Global Graphic Translation Table. The virtual address page table used by a GPU to reference system memory. GMA Graphics Memory Address GPU Graphics Processing Unit GTT Graphic Translation Table GTTMMADR Graphic Translation Table Memory Map Address GuC Graphic Micro-controller GVT Graphics Virtual Technology. GVT-g core device model module up-streamed to the Linux kernel. GVT-d Virtual dedicated graphics acceleration (one VM to one physical GPU) GVT-g Virtual graphics processing unit (multiple VMs to one physical GPU) GVT-s 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 :term:`Hidden GM` 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. I2C Inter-Integrated Circuit i915 The Intel Graphics driver IC Instrument Cluster IDT 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. ISR 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. IVE In-Vehicle Experience IVI In-vehicle Infotainment OS Operating System OSPM Operating System Power Management Passthrough Device Physical devices (typically PCI) exclusively assigned to a guest. In the Project ACRN architecture, passthrough devices are owned by the foreground OS. Partition Mode One of three operation modes (partition, sharing, hybrid) that ACRN supports. Physical hardware resources are partitioned to individual user VMs. PCI Peripheral Component Interface. PDE Page Directory Entry PM Power Management Pre-launched VM Pre-launched VMs are started by the ACRN hypervisor before the Service VM is launched. (See :term:`Post-launched VM`) Post-launched VM Post-Launched VMs are launched and configured by the Service VM. (See :term:`Pre-launched VM`) PTE Page Table Entry PV Para-virtualization (See https://en.wikipedia.org/wiki/Paravirtualization) PVINFO Para-Virtualization Information Page, a MMIO range used to implement para-virtualization QEMU Quick EMUlator. Machine emulator running in user space. RSE Rear Seat Entertainment RDT 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). RTVM 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 :term:`Pre-launched VM`. A non-:term:`Safety VM` with real-time requirements is a :term:`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. SDC Software Defined Cockpit 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. SOS Obsolete, see :term:`Service VM` Service OS Obsolete, see :term:`Service VM` UEFI 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. User VM User Virtual Machine. UOS Obsolete, see :term:`User VM` User OS Obsolete, see :term:`User VM` vGPU Virtual GPU Instance, created by GVT-g and used by a VM VHM Virtio and Hypervisor Service Module Virtio-BE 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 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 VM Virtual Machine, a guest OS running environment VMM Virtual Machine Monitor VMX Virtual Machine Extension VT Intel Virtualization Technology VT-d Virtualization Technology for Directed I/O