computing Computing is any goal-oriented activity requiring, benefiting from, or creating computer, computing machinery. It includes the study and experimentation of algorithmic processes, and the development of both computer hardware, hardware and softw ...

, Quark is an

operating system An operating system (OS) is system software that manages computer hardware and software resources, and provides common daemon (computing), services for computer programs. Time-sharing operating systems scheduler (computing), schedule tasks for ...

kernel Kernel may refer to: Computing * Kernel (operating system), the central component of most operating systems * Kernel (image processing), a matrix used for image convolution * Compute kernel, in GPGPU programming * Kernel method, in machine learnin ...

used in

MorphOS MorphOS is an AmigaOS-like operating system designed for Power and PowerPC based computers. The core, based on the Quark microkernel, is proprietary, although several libraries and other parts are open source, such as the Ambient desktop. The p ...

. It is a

microkernel In computer science, a microkernel (often abbreviated as μ-kernel) is the near-minimum amount of software that can provide the mechanisms needed to implement an operating system (OS). These mechanisms include low-level address space management, ...

designed to run fully virtualized computers, called ''boxes'' (see

sandbox A sandbox is a sandpit, a wide, shallow playground construction to hold sand, often made of wood or plastic. Sandbox or sand box may also refer to: Arts, entertainment, and media * Sandbox (band), a Canadian rock music group * Sandbox (Gu ...

). , only one ''box'' is available, the ''ABox'', that lets users run extant

AmigaOS AmigaOS is a family of proprietary native operating systems of the Amiga and AmigaOne personal computers. It was developed first by Commodore International and introduced with the launch of the first Amiga, the Amiga 1000, in 1985. Early versions ...

software compiled for

Motorola 68000 series The Motorola 68000 series (also known as 680x0, m68000, m68k, or 68k) is a family of 32-bit computing, 32-bit complex instruction set computer (CISC) microprocessors. During the 1980s and early 1990s, they were popular in personal computers and ...

(MC680x0 or 68k) and

PowerPC PowerPC (with the backronym Performance Optimization With Enhanced RISC – Performance Computing, sometimes abbreviated as PPC) is a reduced instruction set computer (RISC) instruction set architecture (ISA) created by the 1991 Apple Inc., App ...

central processing unit A central processing unit (CPU), also called a central processor, main processor, or just processor, is the primary Processor (computing), processor in a given computer. Its electronic circuitry executes Instruction (computing), instructions ...

s (CPUs).

Design goals

The Quark microkernel is not a member of the

L4 microkernel family L4 is a family of second-generation microkernels, used to implement a variety of types of operating systems (OS), though mostly for Unix-like, ''Portable Operating System Interface'' (POSIX) compliant types. L4, like its predecessor microkernel ...

, but borrows concepts from it, including: the ''clan'' (group of tasks), ID concept, and recursive address mapping. Quark also has an asynchronous/synchronous message interface similar to

Amiga Amiga is a family of personal computers produced by Commodore International, Commodore from 1985 until the company's bankruptcy in 1994, with production by others afterward. The original model is one of a number of mid-1980s computers with 16-b ...

's Exec kernel but adapted to an environment with

memory protection Memory protection is a way to control memory access rights on a computer, and is a part of most modern instruction set architectures and operating systems. The main purpose of memory protection is to prevent a process from accessing memory that h ...

. Other Quark features include: * High super/usermode switch speed * Low interrupt latency *

Interrupt In digital computers, an interrupt (sometimes referred to as a trap) is a request for the processor to ''interrupt'' currently executing code (when permitted), so that the event can be processed in a timely manner. If the request is accepted ...

threads (IntThreads) and Int

P-code Bytecode (also called portable code or p-code) is a form of instruction set designed for efficient execution by a software interpreter. Unlike human-readable source code, bytecodes are compact numeric codes, constants, and references (normal ...

abstraction *

Symmetric multiprocessing Symmetric multiprocessing or shared-memory multiprocessing (SMP) involves a multiprocessor computer hardware and software architecture where two or more identical processors are connected to a single, shared main memory, have full access to all ...

(SMP) * Models task/thread and clan/chief * Resource tracking *

Virtual memory In computing, virtual memory, or virtual storage, is a memory management technique that provides an "idealized abstraction of the storage resources that are actually available on a given machine" which "creates the illusion to users of a ver ...

(optional) *

Distributed computing Distributed computing is a field of computer science that studies distributed systems, defined as computer systems whose inter-communicating components are located on different networked computers. The components of a distributed system commu ...

* No access to

structures * Clean design with an elegant application programming interface (

API An application programming interface (API) is a connection between computers or between computer programs. It is a type of software interface, offering a service to other pieces of software. A document or standard that describes how to build ...

) * Micro/pico kernel mix For this new kernel, a

hardware abstraction layer Hardware abstractions are sets of routines in software that provide programs with access to hardware resources through programming interfaces. The programming interface allows all devices in a particular class ''C'' of hardware devices to be acc ...

is used which provides the needed hardware resource information like scanning all

Amiga Zorro II Zorro II is the general purpose expansion bus used by the Amiga 2000 computer. The bus is mainly a buffered extension of the Motorola 68000 bus, with support for bus mastering DMA. The expansion slots use a 100-pin connector and the card form f ...

bus boards,

Peripheral Component Interconnect Peripheral Component Interconnect (PCI) is a local computer bus for attaching hardware devices in a computer and is part of the PCI Local Bus standard. The PCI bus supports the functions found on a processor bus but in a standardized format ...

(PCI) boards, and local hardware resources.

Functions

* SYS_AddLinkMessage * SYS_AttemptSemaphore * SYS_AttemptSemaphoreShared * SYS_CopyCPUHalConfig * SYS_CreateMemList * SYS_CreateTask * SYS_DeletePort * SYS_DeleteSemaphore * SYS_DumpMemHeader * SYS_FindFreeMemArea * SYS_FindSkipSize * SYS_GetLinkMessage * SYS_GetMessageAttr * SYS_GetNextCPU * SYS_Init * SYS_InsideClan * SYS_IsClanMember * SYS_MMUAddPage * SYS_MMUGetEntry * SYS_MoveRomModuleToMemoryEnd * SYS_ObtainPort * SYS_ObtainSemaphore * SYS_ObtainSemaphoreShared * SYS_ReleaseSemaphore * SYS_ReplyMessage * SYS_SendMessage * SYS_SetMessageAttr * SYS_SetupPageTable * SYS_ShowExceptionThreads * SYS_ShowForbidThreads * SYS_ShowIntThreads * SYS_ShowQuarkState * SYS_ShowReadyThreads * SYS_ShowRunThreads * SYS_ShowThreads * SYS_ShowWaitIntThreads * SYS_ShowWaitThreads * SYS_Start * SYS_StartNextThread * SYS_StartThread * SYS_WaitPort

Trance JIT

'' Trance JIT'' is a

just-in-time (JIT)

compiler In computing, a compiler is a computer program that Translator (computing), translates computer code written in one programming language (the ''source'' language) into another language (the ''target'' language). The name "compiler" is primaril ...

, or code translator, for running 68k applications within the MorphOS environment. It has been part of the MorphOS operating system since MorphOS 1.4. MorphOS has a fully integrated 68k emulator to run many Amiga applications, which were almost exclusively compiled for the 68k processor, though MorphOS runs on

. Trance supplements this function by adding JIT compiling, increasing the speed of the emulation. It does not interfere with the full integration of 68k and PowerPC tasks MorphOS provides. Trance exists in the form of an executable, run during boot, and a shared library. Although it is not technically part of the kernel, and MorphOS can be run without it, Trance is considered a fundamental part of MorphOS and one of its most powerful features. Compatibility of Trance is considered to be very high and there are few to no 68k instruction sequences or applications which cause it any problems. It is also considered to be very fast, with users noticing few differences between 68k programs and native PowerPC code. Trance was developed by Ralph Schmidt and Teemu Suikki, with minor support from other MorphOS team members, Mark Olsen, Sigbjørn Skjæret, and Harry Sintonen.

ABox

Under the Quark kernel, a

native reimplementation of the OS known from the

Commodore International Commodore International Corporation was a home computer and electronics manufacturer with its head office in The Bahamas and its executive office in the United States founded in 1976 by Jack Tramiel and Irving Gould. It was the successor compan ...

A1000, A500(+), A600, A2000, A1200, A3000(T), and A4000(T) systems runs as a mix of a virtual emulation and a driver. This OS driver is called an ABox. The 68k emulation is written in C and uses

GNU Compiler Collection The GNU Compiler Collection (GCC) is a collection of compilers from the GNU Project that support various programming languages, Computer architecture, hardware architectures, and operating systems. The Free Software Foundation (FSF) distributes ...

(GCC)

assembly language In computing, assembly language (alternatively assembler language or symbolic machine code), often referred to simply as assembly and commonly abbreviated as ASM or asm, is any low-level programming language with a very strong correspondence bet ...

macros where needed to speed up some complex instructions. A JIT engine named

Trance Trance is a state of semi-consciousness in which a person is not self-aware and is either altogether unresponsive to external stimuli (but nevertheless capable of pursuing and realizing an aim) or is selectively responsive in following the dir ...

is also available for MorphOS, to speed up old 68k programs beyond the current state of the traditional emulation. The PPC native Exec supports the PowerPC register model which means there is no difference for this Exec if it runs 68k or PowerPC code. PowerPC code does not block multitasking inside the OS box like in emulations where the 68k code is just emulated in some host system's task (then every access outside this environment would stop the multitasking in the emulated environment). For applications running under this new PowerPC ABox kernel 68k code runs as subroutines inside PowerPC tasks. For 68k or PowerPC applications it's fully transparent if some library, hook, interrupt is still 68k or already using PowerPC code.

References

{{Microkernel Microkernels MorphOS