[PATCH] doxygen: Replace and move main page
Sebastian Huber
sebastian.huber at embedded-brains.de
Fri Jul 28 14:37:17 UTC 2023
Replace the main page with a high level description of the RTEMS feature
set similar to:
https://docs.rtems.org/branches/master/user/overview/index.html#features
The replaced content can be found in the RTEMS Classic API Guide:
https://docs.rtems.org/branches/master/c-user/overview.html
https://docs.rtems.org/branches/master/c-user/key_concepts.html
Update #3705.
---
v2:
* Add OAR copyright.
* Move to cpukit/doxygen/mainpage.h
* Not not install
cpukit/doxygen/mainpage.h | 204 ++++++
cpukit/include/rtems/rtems/mainpage.h | 951 --------------------------
spec/build/cpukit/librtemscpu.yml | 1 -
3 files changed, 204 insertions(+), 952 deletions(-)
create mode 100644 cpukit/doxygen/mainpage.h
delete mode 100644 cpukit/include/rtems/rtems/mainpage.h
diff --git a/cpukit/doxygen/mainpage.h b/cpukit/doxygen/mainpage.h
new file mode 100644
index 0000000000..ce341e0ffd
--- /dev/null
+++ b/cpukit/doxygen/mainpage.h
@@ -0,0 +1,204 @@
+/* SPDX-License-Identifier: BSD-2-Clause */
+
+/**
+ * @file
+ *
+ * @ingroup RTEMSImplDoxygen
+ *
+ * @brief This file exists to provide a top level description of RTEMS for
+ * Doxygen.
+ */
+
+/*
+ * Copyright (C) 2021 embedded brains GmbH & Co. KG
+ * Copyright (C) 1989, 2014 On-Line Applications Research Corporation (OAR)
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/**
+ * @mainpage
+ *
+ * The Real-Time Executive for Multiprocessor Systems (RTEMS) is a
+ * multi-threaded, single address-space, real-time operating system with no
+ * kernel-space/user-space separation. It is capable to operate in an SMP
+ * configuration providing a state of the art feature set.
+ *
+ * RTEMS and all third-party software distributed with RTEMS which may be
+ * linked to the application is licensed under permissive open source licenses.
+ * This means that the licenses do not properagate to the application software.
+ * Most of the original RTEMS code is now under the [BSD 2-Clause
+ * license](https://git.rtems.org/rtems/tree/LICENSE.BSD-2-Clause). Legacy
+ * code of RTEMS is under a [modified GPL 2.0 or later license with an
+ * exception for static linking](https://git.rtems.org/rtems/tree/LICENSE>).
+ * It exposes no license requirements on application code. Everything
+ * necessary to build RTEMS applications is available as open source software.
+ * This makes you completely vendor independent.
+ *
+ * RTEMS provides the following basic feature set:
+ *
+ * - @ref RTEMSAPI
+ *
+ * - POSIX with
+ * [pthreads](http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/pthread.h.html)
+ * (enables a broad range of standard software to run on RTEMS)
+ *
+ * - @ref RTEMSAPIClassic
+ *
+ * - C11 (including
+ * [thread](https://en.cppreference.com/w/c/thread) support)
+ *
+ * - C++11 (including
+ * [thread](https://en.cppreference.com/w/cpp/thread>) support)
+ *
+ * - Newlib and GCC internal
+ *
+ * - Programming languages
+ *
+ * - C/C++/OpenMP (RTEMS Source Builder, RSB)
+ *
+ * - Ada (RSB, ``--with-ada``)
+ *
+ * - Erlang
+ *
+ * - Fortran (RSB, ``--with-fortran``)
+ *
+ * - Python and MicroPython
+ *
+ * - Parallel languages
+ *
+ * - [Embedded Multicore Building Blocks](https://embb.io/)
+ *
+ * - [OpenMP](https://www.openmp.org/)
+ *
+ * - Thread synchronization and communication
+ *
+ * - Mutexes with and without locking protocols
+ *
+ * - Counting semaphores
+ *
+ * - Binary semaphores
+ *
+ * - Condition variables
+ *
+ * - Events
+ *
+ * - Message queues
+ *
+ * - Barriers
+ *
+ * - [Futex](@ref RTEMSScoreFutex) (used by OpenMP barriers)
+ *
+ * - Epoch Based Reclamation (libbsd)
+ *
+ * - Locking protocols
+ *
+ * - Transitive Priority Inheritance
+ *
+ * - OMIP (SMP feature)
+ *
+ * - Priority Ceiling
+ *
+ * - MrsP (SMP feature)
+ *
+ * - Scalable timer and timeout support
+ *
+ * - Lock-free timestamps (FreeBSD timecounters)
+ *
+ * - Responsive interrupt management
+ *
+ * - C11/C++11 Thread-Local Storage (TLS)
+ *
+ * - Link-time configurable schedulers
+ *
+ * - Fixed-priority
+ *
+ * - Job-level fixed-priority (EDF)
+ *
+ * - Constant Bandwidth Server (experimental)
+ *
+ * - Clustered scheduling (SMP feature)
+ *
+ * - Flexible link-time configuration
+ *
+ * - Job-level fixed-priority scheduler (EDF) with support for one-to-one
+ * and one-to-all thread to processor affinities (default SMP scheduler)
+ *
+ * - Fixed-priority scheduler
+ *
+ * - Proof-of-concept strong APA scheduler
+ *
+ * - Focus on link-time application-specific configuration
+ *
+ * - Linker-set based initialization (similar to global C++ constructors)
+ *
+ * - Operating system uses fine-grained locking (SMP feature)
+ *
+ * - Dynamic memory allocators
+ *
+ * - First-fit (default)
+ *
+ * - Universal Memory Allocator
+ * ([UMA](https://www.freebsd.org/cgi/man.cgi?query=uma&sektion=9),
+ * libbsd)
+ *
+ * - File systems
+ *
+ * - IMFS
+ *
+ * - FAT
+ *
+ * - RFS
+ *
+ * - NFSv2
+ *
+ * - JFFS2 (NOR flashes)
+ *
+ * - [YAFFS2](https://git.rtems.org/sebh/rtems-yaffs2.git/)
+ * (NAND flashes, GPL or commercial license required)
+ *
+ * - Device drivers
+ *
+ * - Termios (serial interfaces)
+ *
+ * - I2C (Linux user-space API compatible)
+ *
+ * - SPI (Linux user-space API compatible)
+ *
+ * - Network stacks (legacy, libbsd, lwIP)
+ *
+ * - USB stack (libbsd)
+ *
+ * - SD/MMC card stack (libbsd)
+ *
+ * - Framebuffer (Linux user-space API compatible, Qt)
+ *
+ * - Application runs in kernel-space and can access hardware directly
+ *
+ * - [libbsd](https://git.rtems.org/rtems-libbsd/)
+ *
+ * - Port of FreeBSD user-space and kernel-space components to RTEMS
+ *
+ * - Easy access to FreeBSD software for RTEMS
+ *
+ * - Support to stay in synchronization with FreeBSD
+ */
diff --git a/cpukit/include/rtems/rtems/mainpage.h b/cpukit/include/rtems/rtems/mainpage.h
deleted file mode 100644
index f168cc3395..0000000000
--- a/cpukit/include/rtems/rtems/mainpage.h
+++ /dev/null
@@ -1,951 +0,0 @@
-/* SPDX-License-Identifier: BSD-2-Clause */
-
-/**
- * @file
- *
- * @ingroup RTEMSImplDoxygen
- *
- * @brief This file exists to provide a top level description of RTEMS for
- * Doxygen.
- */
-
-/*
- * COPYRIGHT (c) 1989-2014.
- * On-Line Applications Research Corporation (OAR).
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
- * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
- * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
- * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
- * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
- * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
- * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
- * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
- * POSSIBILITY OF SUCH DAMAGE.
- */
-
-/**
- * @mainpage
- *
- * The RTEMS real-time operating systems is a layered system with each of the
- * public APIs implemented in terms of a common foundation layer called the
- * SuperCore. This is the Doxygen generated documentation for the RTEMS CPU
- * Kit including the Classic API, POSIX API and SuperCore.
- */
-
-/**
- * @page RTEMSPreface RTEMS History and Introduction
- *
- * In recent years, the cost required to develop a software product has
- * increased significantly while the target hardware costs have decreased. Now
- * a larger portion of money is expended in developing, using, and maintaining
- * software. The trend in computing costs is the complete dominance of software
- * over hardware costs. Because of this, it is necessary that formal
- * disciplines be established to increase the probability that software is
- * characterized by a high degree of correctness, maintainability, and
- * portability. In addition, these disciplines must promote practices that aid
- * in the consistent and orderly development of a software system within
- * schedule and budgetary constraints. To be effective, these disciplines must
- * adopt standards which channel individual software efforts toward a common
- * goal.
- *
- * The push for standards in the software development field has been met with
- * various degrees of success. The Microprocessor Operating Systems Interfaces
- * (MOSI) effort has experienced only limited success. As popular as the UNIX
- * operating system has grown, the attempt to develop a standard interface
- * definition to allow portable application development has only recently begun
- * to produce the results needed in this area. Unfortunately, very little
- * effort has been expended to provide standards addressing the needs of the
- * real-time community. Several organizations have addressed this need during
- * recent years.
- *
- * The Real Time Executive Interface Definition (RTEID) was developed by
- * Motorola with technical input from Software Components Group. RTEID was
- * adopted by the VMEbus International Trade Association (VITA) as a baseline
- * draft for their proposed standard multiprocessor, real-time executive
- * interface, Open Real-Time Kernel Interface Definition (ORKID). These two
- * groups are currently working together with the IEEE P1003.4 committee to
- * insure that the functionality of their proposed standards is adopted as the
- * real-time extensions to POSIX.
- *
- * This emerging standard defines an interface for the development of real-time
- * software to ease the writing of real-time application programs that are
- * directly portable across multiple real-time executive implementations. This
- * interface includes both the source code interfaces and run-time behavior as
- * seen by a real-time application. It does not include the details of how a
- * kernel implements these functions. The standard's goal is to serve as a
- * complete definition of external interfaces so that application code that
- * conforms to these interfaces will execute properly in all real-time
- * executive environments. With the use of a standards compliant executive,
- * routines that acquire memory blocks, create and manage message queues,
- * establish and use semaphores, and send and receive signals need not be
- * redeveloped for a different real-time environment as long as the new
- * environment is compliant with the standard. Software developers need only
- * concentrate on the hardware dependencies of the real-time system.
- * Furthermore, most hardware dependencies for real-time applications can be
- * localized to the device drivers.
- *
- * A compliant executive provides simple and flexible real-time
- * multiprocessing. It easily lends itself to both tightly-coupled and
- * loosely-coupled configurations (depending on the system hardware
- * configuration). Objects such as tasks, queues, events, signals, semaphores,
- * and memory blocks can be designated as global objects and accessed by any
- * task regardless of which processor the object and the accessing task reside.
- *
- * The acceptance of a standard for real-time executives will produce the same
- * advantages enjoyed from the push for UNIX standardization by AT&T's System V
- * Interface Definition and IEEE's POSIX efforts. A compliant multiprocessing
- * executive will allow close coupling between UNIX systems and real-time
- * executives to provide the many benefits of the UNIX development environment
- * to be applied to real-time software development. Together they provide the
- * necessary laboratory environment to implement real-time, distributed,
- * embedded systems using a wide variety of computer architectures.
- *
- * A study was completed in 1988, within the Research, Development, and
- * Engineering Center, U.S. Army Missile Command, which compared the various
- * aspects of the Ada programming language as they related to the application
- * of Ada code in distributed and/or multiple processing systems. Several
- * critical conclusions were derived from the study. These conclusions have a
- * major impact on the way the Army develops application software for embedded
- * applications. These impacts apply to both in-house software development and
- * contractor developed software.
- *
- * A conclusion of the analysis, which has been previously recognized by other
- * agencies attempting to utilize Ada in a distributed or multiprocessing
- * environment, is that the Ada programming language does not adequately
- * support multiprocessing. Ada does provide a mechanism for multi-tasking,
- * however, this capability exists only for a single processor system. The
- * language also does not have inherent capabilities to access global named
- * variables, flags or program code. These critical features are essential in
- * order for data to be shared between processors. However, these drawbacks do
- * have workarounds which are sometimes awkward and defeat the intent of
- * software maintainability and portability goals.
- *
- * Another conclusion drawn from the analysis, was that the run time executives
- * being delivered with the Ada compilers were too slow and inefficient to be
- * used in modern missile systems. A run time executive is the core part of the
- * run time system code, or operating system code, that controls task
- * scheduling, input/output management and memory management. Traditionally,
- * whenever efficient executive (also known as kernel) code was required by the
- * application, the user developed in-house software. This software was usually
- * written in assembly language for optimization.
- *
- * Because of this shortcoming in the Ada programming language, software
- * developers in research and development and contractors for project managed
- * systems, are mandated by technology to purchase and utilize off-the-shelf
- * third party kernel code. The contractor, and eventually the Government, must
- * pay a licensing fee for every copy of the kernel code used in an embedded
- * system.
- *
- * The main drawback to this development environment is that the Government
- * does not own, nor has the right to modify code contained within the kernel.
- * V&V techniques in this situation are more difficult than if the complete
- * source code were available. Responsibility for system failures due to faulty
- * software is yet another area to be resolved under this environment.
- *
- * The Guidance and Control Directorate began a software development effort to
- * address these problems. A project to develop an experimental run time kernel
- * was begun that will eliminate the major drawbacks of the Ada programming
- * language mentioned above. The Real Time Executive for Multiprocessor Systems
- * (RTEMS) provides full capabilities for management of tasks, interrupts,
- * time, and multiple processors in addition to those features typical of
- * generic operating systems. The code is Government owned, so no licensing
- * fees are necessary. RTEMS has been implemented in both the Ada and C
- * programming languages. It has been ported to the following processor
- * families:
- *
- * - Altera NIOS II
- * - Analog Devices Blackfin
- * - ARM
- * - Freescale (formerly Motorola) MC68xxx
- * - Freescale (formerly Motorola) MC683xx
- * - Freescale (formerly Motorola) ColdFire
- * - Intel i386 and above
- * - Lattice Semiconductor LM32
- * - MIPS
- * - PowerPC
- * - Renesas (formerly Hitachi) SuperH
- * - Renesas (formerly Hitachi) H8/300
- * - SPARC
- * - Texas Instruments C3x/C4x
- * - UNIX
- *
- * Support for other processor families, including RISC, CISC, and DSP, is
- * planned. Since almost all of RTEMS is written in a high level language,
- * ports to additional processor families require minimal effort.
- *
- * RTEMS multiprocessor support is capable of handling either homogeneous or
- * heterogeneous systems. The kernel automatically compensates for
- * architectural differences (byte swapping, etc.) between processors. This
- * allows a much easier transition from one processor family to another without
- * a major system redesign.
- *
- * Since the proposed standards are still in draft form, RTEMS cannot and does
- * not claim compliance. However, the status of the standard is being carefully
- * monitored to guarantee that RTEMS provides the functionality specified in
- * the standard. Once approved, RTEMS will be made compliant.
- */
-
-/**
- * @page RTEMSOverview RTEMS Overview
- *
- * @section RTEMSOverviewSecIntroduction Introduction
- *
- * RTEMS, Real-Time Executive for Multiprocessor Systems, is a real-time
- * executive (kernel) which provides a high performance environment for
- * embedded military applications including the following features:
- *
- * - multitasking capabilities
- * - homogeneous and heterogeneous multiprocessor systems
- * - event-driven, priority-based, preemptive scheduling
- * - optional rate monotonic scheduling
- * - intertask communication and synchronization
- * - priority inheritance
- * - responsive interrupt management
- * - dynamic memory allocation
- * - high level of user configurability
- *
- * This manual describes the usage of RTEMS for applications written in the C
- * programming language. Those implementation details that are processor
- * dependent are provided in the Applications Supplement documents. A
- * supplement document which addresses specific architectural issues that
- * affect RTEMS is provided for each processor type that is supported.
- *
- * @section RTEMSOverviewSecRealtimeApplicationSystems Real-time Application Systems
- *
- * Real-time application systems are a special class of computer applications.
- * They have a complex set of characteristics that distinguish them from other
- * software problems. Generally, they must adhere to more rigorous
- * requirements. The correctness of the system depends not only on the results
- * of computations, but also on the time at which the results are produced. The
- * most important and complex characteristic of real-time application systems
- * is that they must receive and respond to a set of external stimuli within
- * rigid and critical time constraints referred to as deadlines. Systems can be
- * buried by an avalanche of interdependent, asynchronous or cyclical event
- * streams.
- *
- * Deadlines can be further characterized as either hard or soft based upon the
- * value of the results when produced after the deadline has passed. A deadline
- * is hard if the results have no value or if their use will result in a
- * catastrophic event. In contrast, results which are produced after a soft
- * deadline may have some value.
- *
- * Another distinguishing requirement of real-time application systems is the
- * ability to coordinate or manage a large number of concurrent activities.
- * Since software is a synchronous entity, this presents special problems. One
- * instruction follows another in a repeating synchronous cycle. Even though
- * mechanisms have been developed to allow for the processing of external
- * asynchronous events, the software design efforts required to process and
- * manage these events and tasks are growing more complicated.
- *
- * The design process is complicated further by spreading this activity over a
- * set of processors instead of a single processor. The challenges associated
- * with designing and building real-time application systems become very
- * complex when multiple processors are involved. New requirements such as
- * interprocessor communication channels and global resources that must be
- * shared between competing processors are introduced. The ramifications of
- * multiple processors complicate each and every characteristic of a real-time
- * system.
- *
- * @section RTEMSOverviewSecRealtimeExecutive Real-time Executive
- *
- * Fortunately, real-time operating systems or real-time executives serve as a
- * cornerstone on which to build the application system. A real-time
- * multitasking executive allows an application to be cast into a set of
- * logical, autonomous processes or tasks which become quite manageable. Each
- * task is internally synchronous, but different tasks execute independently,
- * resulting in an asynchronous processing stream. Tasks can be dynamically
- * paused for many reasons resulting in a different task being allowed to
- * execute for a period of time. The executive also provides an interface to
- * other system components such as interrupt handlers and device drivers.
- * System components may request the executive to allocate and coordinate
- * resources, and to wait for and trigger synchronizing conditions. The
- * executive system calls effectively extend the CPU instruction set to support
- * efficient multitasking. By causing tasks to travel through well-defined
- * state transitions, system calls permit an application to demand-switch
- * between tasks in response to real-time events.
- *
- * By proper grouping of responses to stimuli into separate tasks, a system can
- * now asynchronously switch between independent streams of execution, directly
- * responding to external stimuli as they occur. This allows the system design
- * to meet critical performance specifications which are typically measured by
- * guaranteed response time and transaction throughput. The multiprocessor
- * extensions of RTEMS provide the features necessary to manage the extra
- * requirements introduced by a system distributed across several processors.
- * It removes the physical barriers of processor boundaries from the world of
- * the system designer, enabling more critical aspects of the system to receive
- * the required attention. Such a system, based on an efficient real-time,
- * multiprocessor executive, is a more realistic model of the outside world or
- * environment for which it is designed. As a result, the system will always be
- * more logical, efficient, and reliable.
- *
- * By using the directives provided by RTEMS, the real-time applications
- * developer is freed from the problem of controlling and synchronizing
- * multiple tasks and processors. In addition, one need not develop, test,
- * debug, and document routines to manage memory, pass messages, or provide
- * mutual exclusion. The developer is then able to concentrate solely on the
- * application. By using standard software components, the time and cost
- * required to develop sophisticated real-time applications is significantly
- * reduced.
- *
- * @section RTEMSOverviewSecApplicationArchitecture RTEMS Application Architecture
- *
- * One important design goal of RTEMS was to provide a bridge between two
- * critical layers of typical real-time systems. As shown in the following
- * figure, RTEMS serves as a buffer between the project dependent application
- * code and the target hardware. Most hardware dependencies for real-time
- * applications can be localized to the low level device drivers.
- *
- * @todo Image RTEMS Application Architecture
- *
- * The RTEMS I/O interface manager provides an efficient tool for incorporating
- * these hardware dependencies into the system while simultaneously providing a
- * general mechanism to the application code that accesses them. A well
- * designed real-time system can benefit from this architecture by building a
- * rich library of standard application components which can be used repeatedly
- * in other real-time projects.
- *
- * @section RTEMSOverviewSecInternalArchitecture RTEMS Internal Architecture
- *
- * RTEMS can be viewed as a set of layered components that work in harmony to
- * provide a set of services to a real-time application system. The executive
- * interface presented to the application is formed by grouping directives into
- * logical sets called resource managers. Functions utilized by multiple
- * managers such as scheduling, dispatching, and object management are provided
- * in the executive core. The executive core depends on a small set of CPU
- * dependent routines. Together these components provide a powerful run time
- * environment that promotes the development of efficient real-time application
- * systems. The following figure illustrates this organization:
- *
- * @todo Image RTEMS Architecture
- *
- * Subsequent chapters present a detailed description of the capabilities
- * provided by each of the following RTEMS managers:
- *
- * - initialization
- * - task
- * - interrupt
- * - clock
- * - timer
- * - semaphore
- * - message
- * - event
- * - signal
- * - partition
- * - region
- * - dual ported memory
- * - I/O
- * - fatal error
- * - rate monotonic
- * - user extensions
- * - multiprocessing
- *
- * @section RTEMSOverviewSecUserCustomization User Customization and Extensibility
- *
- * As 32-bit microprocessors have decreased in cost, they have become
- * increasingly common in a variety of embedded systems. A wide range of custom
- * and general-purpose processor boards are based on various 32-bit
- * processors. RTEMS was designed to make no assumptions concerning the
- * characteristics of individual microprocessor families or of specific support
- * hardware. In addition, RTEMS allows the system developer a high degree of
- * freedom in customizing and extending its features.
- *
- * RTEMS assumes the existence of a supported microprocessor and sufficient
- * memory for both RTEMS and the real-time application. Board dependent
- * components such as clocks, interrupt controllers, or I/O devices can be
- * easily integrated with RTEMS. The customization and extensibility features
- * allow RTEMS to efficiently support as many environments as possible.
- *
- * @section RTEMSOverviewSecPortability Portability
- *
- * The issue of portability was the major factor in the creation of RTEMS.
- * Since RTEMS is designed to isolate the hardware dependencies in the specific
- * board support packages, the real-time application should be easily ported to
- * any other processor. The use of RTEMS allows the development of real-time
- * applications which can be completely independent of a particular
- * microprocessor architecture.
- *
- * @section RTEMSOverviewSecMemoryRequirements Memory Requirements
- *
- * Since memory is a critical resource in many real-time embedded systems,
- * RTEMS was specifically designed to automatically leave out all services that
- * are not required from the run-time environment. Features such as networking,
- * various filesystems, and many other features are completely optional. This
- * allows the application designer the flexibility to tailor RTEMS to most
- * efficiently meet system requirements while still satisfying even the most
- * stringent memory constraints. As a result, the size of the RTEMS executive
- * is application dependent.
- *
- * RTEMS requires RAM to manage each instance of an RTEMS object that is
- * created. Thus the more RTEMS objects an application needs, the more memory
- * that must be reserved. See Configuring a System Determining Memory
- * Requirements for more details.
- *
- * @todo Link to Configuring a SystemDetermining Memory Requirements
- *
- * RTEMS utilizes memory for both code and data space. Although RTEMS' data
- * space must be in RAM, its code space can be located in either ROM or RAM.
- *
- * @section RTEMSOverviewSecAudience Audience
- *
- * This manual was written for experienced real-time software developers.
- * Although some background is provided, it is assumed that the reader is
- * familiar with the concepts of task management as well as intertask
- * communication and synchronization. Since directives, user related data
- * structures, and examples are presented in C, a basic understanding of the C
- * programming language is required to fully understand the material presented.
- * However, because of the similarity of the Ada and C RTEMS implementations,
- * users will find that the use and behavior of the two implementations is very
- * similar. A working knowledge of the target processor is helpful in
- * understanding some of RTEMS' features. A thorough understanding of the
- * executive cannot be obtained without studying the entire manual because many
- * of RTEMS' concepts and features are interrelated. Experienced RTEMS users
- * will find that the manual organization facilitates its use as a reference
- * document.
- */
-
-/**
- * @addtogroup RTEMSAPIClassic
- *
- * The facilities provided by RTEMS are built upon a foundation of very
- * powerful concepts. These concepts must be understood before the application
- * developer can efficiently utilize RTEMS. The purpose of this chapter is to
- * familiarize one with these concepts.
- *
- * @section ClassicRTEMSSecObjects Objects
- *
- * RTEMS provides directives which can be used to dynamically create, delete,
- * and manipulate a set of predefined object types. These types include tasks,
- * message queues, semaphores, memory regions, memory partitions, timers,
- * ports, and rate monotonic periods. The object-oriented nature of RTEMS
- * encourages the creation of modular applications built upon re-usable
- * "building block" routines.
- *
- * All objects are created on the local node as required by the application and
- * have an RTEMS assigned ID. All objects have a user-assigned name. Although a
- * relationship exists between an object's name and its RTEMS assigned ID, the
- * name and ID are not identical. Object names are completely arbitrary and
- * selected by the user as a meaningful "tag" which may commonly reflect the
- * object's use in the application. Conversely, object IDs are designed to
- * facilitate efficient object manipulation by the executive.
- *
- * @subsection ClassicRTEMSSubSecObjectNames Object Names
- *
- * An object name is an unsigned 32-bit entity associated with the
- * object by the user. The data type @ref rtems_name is used to store object names.
- *
- * Although not required by RTEMS, object names are often composed of four
- * ASCII characters which help identify that object. For example, a task which
- * causes a light to blink might be called "LITE". The rtems_build_name()
- * routine is provided to build an object name from four ASCII characters. The
- * following example illustrates this:
- *
- * @code
- * rtems_name my_name = rtems_build_name('L', 'I', 'T', 'E');
- * @endcode
- *
- * However, it is not required that the application use ASCII characters to
- * build object names. For example, if an application requires one-hundred
- * tasks, it would be difficult to assign meaningful ASCII names to each task.
- * A more convenient approach would be to name them the binary values one
- * through one-hundred, respectively.
- *
- * RTEMS provides a helper routine, rtems_object_get_name(), which can be used to
- * obtain the name of any RTEMS object using just its ID. This routine attempts
- * to convert the name into a printable string.
- *
- * @subsection ClassicRTEMSSubSecObjectIdentifiers Object Identifiers
- *
- * An object ID is a unique unsigned integer value which uniquely identifies an
- * object instance. Object IDs are passed as arguments to many directives in
- * RTEMS and RTEMS translates the ID to an internal object pointer. The
- * efficient manipulation of object IDs is critical to the performance of RTEMS
- * services. Because of this, there are two object ID formats defined. Each
- * target architecture specifies which format it will use. There is a 32-bit
- * format which is used for most of the supported architectures and supports
- * multiprocessor configurations. There is also a simpler 16-bit format which
- * is appropriate for smaller target architectures and does not support
- * multiprocessor configurations.
- *
- * @subsubsection ClassicRTEMSSubSec32BitObjectIdentifierFormat 32-Bit Object Identifier Format
- *
- * The 32-bit format for an object ID is composed of four parts: API,
- * object class, node, and index. The data type @ref rtems_id is used to store
- * object IDs.
- *
- * <table>
- * <tr>
- * <th>Bits</th>
- * <td>31</td><td>30</td><td>29</td><td>28</td><td>27</td><td>26</td><td>25</td><td>24</td>
- * <td>23</td><td>22</td><td>21</td><td>20</td><td>19</td><td>18</td><td>17</td><td>16</td>
- * <td>15</td><td>14</td><td>13</td><td>12</td><td>11</td><td>10</td><td>09</td><td>08</td>
- * <td>07</td><td>06</td><td>05</td><td>04</td><td>03</td><td>02</td><td>01</td><td>00</td>
- * </tr>
- * <tr>
- * <th>Contents</th>
- * <td colspan=5>Class</td><td colspan=3>API</td><td colspan=8>Node</td><td colspan=16>Object Index</td>
- * </tr>
- * </table>
- *
- * The most significant five bits are the object class. The next three bits
- * indicate the API to which the object class belongs. The next eight bits
- * (16 .. 23) are the number of the node on which this object was created. The
- * node number is always one (1) in a single processor system. The least
- * significant 16-bits form an identifier within a particular object type.
- * This identifier, called the object index, ranges in value from one to the
- * maximum number of objects configured for this object type.
- *
- * @subsubsection ClassicRTEMSSubSec16BitObjectIdentifierFormat 16-Bit Object Identifier Format
- *
- * The 16-bit format for an object ID is composed of three parts: API, object
- * class, and index. The data type @ref rtems_id is used to store object IDs.
- *
- * <table>
- * <tr>
- * <th>Bits</th>
- * <td>15</td><td>14</td><td>13</td><td>12</td><td>11</td><td>10</td><td>09</td><td>08</td>
- * <td>07</td><td>06</td><td>05</td><td>04</td><td>03</td><td>02</td><td>01</td><td>00</td>
- * </tr>
- * <tr>
- * <th>Contents</th>
- * <td colspan=5>Class</td><td colspan=3>API</td><td colspan=8>Object Index</td>
- * </tr>
- * </table>
- *
- * The 16-bit format is designed to be as similar as possible to the 32-bit
- * format. The differences are limited to the elimination of the node field
- * and reduction of the index field from 16-bits to 8-bits. Thus the 16-bit
- * format only supports up to 255 object instances per API/Class combination
- * and single processor systems. As this format is typically utilized by 16-bit
- * processors with limited address space, this is more than enough object
- * instances.
- *
- * @subsection ClassicRTEMSSubSecObjectIdentiferDescription Object Identifer Description
- *
- * The components of an object ID make it possible to quickly locate any object
- * in even the most complicated multiprocessor system. Object ID's are
- * associated with an object by RTEMS when the object is created and the
- * corresponding ID is returned by the appropriate object create directive. The
- * object ID is required as input to all directives involving objects, except
- * those which create an object or obtain the ID of an object.
- *
- * The object identification directives can be used to dynamically obtain a
- * particular object's ID given its name. This mapping is accomplished by
- * searching the name table associated with this object type. If the name is
- * non-unique, then the ID associated with the first occurrence of the name
- * will be returned to the application. Since object IDs are returned when the
- * object is created, the object identification directives are not necessary in
- * a properly designed single processor application.
- *
- * In addition, services are provided to portably examine the subcomponents of
- * an RTEMS ID. These services are described in detail later in this manual but
- * are prototyped as follows:
- *
- * - rtems_object_id_get_api()
- * - rtems_object_id_get_class()
- * - rtems_object_id_get_node()
- * - rtems_object_id_get_index()
- *
- * An object control block is a data structure defined by RTEMS which contains
- * the information necessary to manage a particular object type. For efficiency
- * reasons, the format of each object type's control block is different.
- * However, many of the fields are similar in function. The number of each type
- * of control block is application dependent and determined by the values
- * specified in the user's Configuration Table. An object control block is
- * allocated at object create time and freed when the object is deleted. With
- * the exception of user extension routines, object control blocks are not
- * directly manipulated by user applications.
- *
- * @section ClassicRTEMSSecComSync Communication and Synchronization
- *
- * In real-time multitasking applications, the ability for cooperating
- * execution threads to communicate and synchronize with each other is
- * imperative. A real-time executive should provide an application with the
- * following capabilities
- *
- * - data transfer between cooperating tasks,
- * - data transfer between tasks and ISRs,
- * - synchronization of cooperating tasks, and
- * - synchronization of tasks and ISRs.
- *
- * Most RTEMS managers can be used to provide some form of communication and/or
- * synchronization. However, managers dedicated specifically to communication
- * and synchronization provide well established mechanisms which directly map
- * to the application's varying needs. This level of flexibility allows the
- * application designer to match the features of a particular manager with the
- * complexity of communication and synchronization required. The following
- * managers were specifically designed for communication and synchronization:
- *
- * - @ref ClassicSem
- * - @ref ClassicMessageQueue
- * - @ref ClassicEvent
- * - @ref ClassicSignal
- *
- * The semaphore manager supports mutual exclusion involving the
- * synchronization of access to one or more shared user resources. Binary
- * semaphores may utilize the optional priority inheritance algorithm to avoid
- * the problem of priority inversion. The message manager supports both
- * communication and synchronization, while the event manager primarily
- * provides a high performance synchronization mechanism. The signal manager
- * supports only asynchronous communication and is typically used for exception
- * handling.
- *
- * @section ClassicRTEMSSecTime Time
- *
- * The development of responsive real-time applications requires an
- * understanding of how RTEMS maintains and supports time-related operations.
- * The basic unit of time in RTEMS is known as a tick. The frequency of clock
- * ticks is completely application dependent and determines the granularity and
- * accuracy of all interval and calendar time operations.
- *
- * By tracking time in units of ticks, RTEMS is capable of supporting interval
- * timing functions such as task delays, timeouts, timeslicing, the delayed
- * execution of timer service routines, and the rate monotonic scheduling of
- * tasks. An interval is defined as a number of ticks relative to the current
- * time. For example, when a task delays for an interval of ten ticks, it is
- * implied that the task will not execute until ten clock ticks have occurred.
- * All intervals are specified using data type @ref rtems_interval.
- *
- * A characteristic of interval timing is that the actual interval period may
- * be a fraction of a tick less than the interval requested. This occurs
- * because the time at which the delay timer is set up occurs at some time
- * between two clock ticks. Therefore, the first countdown tick occurs in less
- * than the complete time interval for a tick. This can be a problem if the
- * clock granularity is large.
- *
- * The rate monotonic scheduling algorithm is a hard real-time scheduling
- * methodology. This methodology provides rules which allows one to guarantee
- * that a set of independent periodic tasks will always meet their deadlines --
- * even under transient overload conditions. The rate monotonic manager
- * provides directives built upon the Clock Manager's interval timer support
- * routines.
- *
- * Interval timing is not sufficient for the many applications which require
- * that time be kept in wall time or true calendar form. Consequently, RTEMS
- * maintains the current date and time. This allows selected time operations to
- * be scheduled at an actual calendar date and time. For example, a task could
- * request to delay until midnight on New Year's Eve before lowering the ball
- * at Times Square. The data type @ref rtems_time_of_day is used to specify
- * calendar time in RTEMS services. See Clock Manager Time and Date Data
- * Structures.
- *
- * @todo Link to Clock Manager Time and Date Data Structures
- *
- * Obviously, the directives which use intervals or wall time cannot operate
- * without some external mechanism which provides a periodic clock tick. This
- * clock tick is typically provided by a real time clock or counter/timer
- * device.
- *
- * @section ClassicRTEMSSecMemoryManagement Memory Management
- *
- * RTEMS memory management facilities can be grouped into two classes: dynamic
- * memory allocation and address translation. Dynamic memory allocation is
- * required by applications whose memory requirements vary through the
- * application's course of execution. Address translation is needed by
- * applications which share memory with another CPU or an intelligent
- * Input/Output processor. The following RTEMS managers provide facilities to
- * manage memory:
- *
- * - @ref ClassicRegion
- * - @ref ClassicPart
- * - @ref ClassicDPMEM
- *
- * RTEMS memory management features allow an application to create simple
- * memory pools of fixed size buffers and/or more complex memory pools of
- * variable size segments. The partition manager provides directives to manage
- * and maintain pools of fixed size entities such as resource control blocks.
- * Alternatively, the region manager provides a more general purpose memory
- * allocation scheme that supports variable size blocks of memory which are
- * dynamically obtained and freed by the application. The dual-ported memory
- * manager provides executive support for address translation between internal
- * and external dual-ported RAM address space.
- */
-
-/**
- * @addtogroup RTEMSAPIClassicTasks
- *
- * @section ClassicTasksSecTaskDefinition Task Definition
- *
- * Many definitions of a task have been proposed in computer literature.
- * Unfortunately, none of these definitions encompasses all facets of the
- * concept in a manner which is operating system independent. Several of the
- * more common definitions are provided to enable each user to select a
- * definition which best matches their own experience and understanding of the
- * task concept:
- *
- * - a "dispatchable" unit.
- * - an entity to which the processor is allocated.
- * - an atomic unit of a real-time, multiprocessor system.
- * - single threads of execution which concurrently compete for resources.
- * - a sequence of closely related computations which can execute concurrently
- * with other computational sequences.
- *
- * From RTEMS' perspective, a task is the smallest thread of execution which
- * can compete on its own for system resources. A task is manifested by the
- * existence of a task control block (TCB).
- *
- * @section ClassicTasksSecTaskControlBlock Task Control Block
- *
- * The Task Control Block (TCB) is an RTEMS defined data structure which
- * contains all the information that is pertinent to the execution of a task.
- * During system initialization, RTEMS reserves a TCB for each task configured.
- * A TCB is allocated upon creation of the task and is returned to the TCB free
- * list upon deletion of the task.
- *
- * The TCB's elements are modified as a result of system calls made by the
- * application in response to external and internal stimuli. TCBs are the only
- * RTEMS internal data structure that can be accessed by an application via
- * user extension routines. The TCB contains a task's name, ID, current
- * priority, current and starting states, execution mode, TCB user extension
- * pointer, scheduling control structures, as well as data required by a
- * blocked task.
- *
- * A task's context is stored in the TCB when a task switch occurs. When the
- * task regains control of the processor, its context is restored from the TCB.
- * When a task is restarted, the initial state of the task is restored from the
- * starting context area in the task's TCB.
- *
- * @section ClassicTasksSecTaskStates Task States
- *
- * A task may exist in one of the following five states:
- *
- * - executing - Currently scheduled to the CPU
- * - ready - May be scheduled to the CPU
- * - blocked - Unable to be scheduled to the CPU
- * - dormant - Created task that is not started
- * - non-existent - Uncreated or deleted task
- *
- * An active task may occupy the executing, ready, blocked or dormant state,
- * otherwise the task is considered non-existent. One or more tasks may be
- * active in the system simultaneously. Multiple tasks communicate,
- * synchronize, and compete for system resources with each other via system
- * calls. The multiple tasks appear to execute in parallel, but actually each
- * is dispatched to the CPU for periods of time determined by the RTEMS
- * scheduling algorithm. The scheduling of a task is based on its current state
- * and priority.
- *
- * @section ClassicTasksSecTaskPriority Task Priority
- *
- * A task's priority determines its importance in relation to the other tasks
- * executing on the same processor. RTEMS supports 255 levels of priority
- * ranging from 1 to 255. The data type rtems_task_priority() is used to store
- * task priorities.
- *
- * Tasks of numerically smaller priority values are more important tasks than
- * tasks of numerically larger priority values. For example, a task at priority
- * level 5 is of higher privilege than a task at priority level 10. There is no
- * limit to the number of tasks assigned to the same priority.
- *
- * Each task has a priority associated with it at all times. The initial value
- * of this priority is assigned at task creation time. The priority of a task
- * may be changed at any subsequent time.
- *
- * Priorities are used by the scheduler to determine which ready task will be
- * allowed to execute. In general, the higher the logical priority of a task,
- * the more likely it is to receive processor execution time.
- *
- * @section ClassicTasksSecTaskMode Task Mode
- *
- * A task's execution mode is a combination of the following four components:
- *
- * - preemption
- * - ASR processing
- * - timeslicing
- * - interrupt level
- *
- * It is used to modify RTEMS' scheduling process and to alter the execution
- * environment of the task. The data type rtems_task_mode() is used to manage
- * the task execution mode.
- *
- * The preemption component allows a task to determine when control of the
- * processor is relinquished. If preemption is disabled (@c
- * RTEMS_NO_PREEMPT), the task will retain control of the
- * processor as long as it is in the executing state -- even if a higher
- * priority task is made ready. If preemption is enabled (@c RTEMS_PREEMPT)
- * and a higher priority task is made ready, then the processor will be
- * taken away from the current task immediately and given to the higher
- * priority task.
- *
- * The timeslicing component is used by the RTEMS scheduler to determine how
- * the processor is allocated to tasks of equal priority. If timeslicing is
- * enabled (@c RTEMS_TIMESLICE), then RTEMS will limit the amount of time the
- * task can execute before the processor is allocated to another ready task of
- * equal priority. The length of the timeslice is application dependent and
- * specified in the Configuration Table. If timeslicing is disabled (@c
- * RTEMS_NO_TIMESLICE), then the task will be allowed to
- * execute until a task of higher priority is made ready. If @c
- * RTEMS_NO_PREEMPT is selected, then the timeslicing component is ignored by
- * the scheduler.
- *
- * The asynchronous signal processing component is used to determine when
- * received signals are to be processed by the task. If signal processing is
- * enabled (@c RTEMS_ASR), then signals sent to the task will be processed
- * the next time the task executes. If signal processing is disabled (@c
- * RTEMS_NO_ASR), then all signals received by the task will
- * remain posted until signal processing is enabled. This component affects
- * only tasks which have established a routine to process asynchronous signals.
- *
- * The interrupt level component is used to determine which interrupts will be
- * enabled when the task is executing. @c RTEMS_INTERRUPT_LEVEL(n) specifies
- * that the task will execute at interrupt level n.
- *
- * - @ref RTEMS_PREEMPT - enable preemption (default)
- * - @ref RTEMS_NO_PREEMPT - disable preemption
- * - @ref RTEMS_NO_TIMESLICE - disable timeslicing (default)
- * - @ref RTEMS_TIMESLICE - enable timeslicing
- * - @ref RTEMS_ASR - enable ASR processing (default)
- * - @ref RTEMS_NO_ASR - disable ASR processing
- * - @ref RTEMS_INTERRUPT_LEVEL(0) - enable all interrupts (default)
- * - @ref RTEMS_INTERRUPT_LEVEL(n) - execute at interrupt level n
- *
- * The set of default modes may be selected by specifying the @ref
- * RTEMS_DEFAULT_MODES constant.
- *
- * @section ClassicTasksSecAccessingTaskArguments Accessing Task Arguments
- *
- * All RTEMS tasks are invoked with a single argument which is specified when
- * they are started or restarted. The argument is commonly used to communicate
- * startup information to the task. The simplest manner in which to define a
- * task which accesses it argument is:
- *
- * @code
- * rtems_task user_task(
- * rtems_task_argument argument
- * );
- * @endcode
- *
- * Application tasks requiring more information may view this single argument
- * as an index into an array of parameter blocks.
- *
- * @section ClassicTasksSecFloatingPointConsiderations Floating Point Considerations
- *
- * Creating a task with the @ref RTEMS_FLOATING_POINT attribute flag results in
- * additional memory being allocated for the TCB to store the state of the
- * numeric coprocessor during task switches. This additional memory is NOT
- * allocated for @ref RTEMS_NO_FLOATING_POINT tasks. Saving and restoring the
- * context of a @c RTEMS_FLOATING_POINT task takes longer than that of a @c
- * RTEMS_NO_FLOATING_POINT task because of the relatively large amount of time
- * required for the numeric coprocessor to save or restore its computational
- * state.
- *
- * Since RTEMS was designed specifically for embedded military applications
- * which are floating point intensive, the executive is optimized to avoid
- * unnecessarily saving and restoring the state of the numeric coprocessor. The
- * state of the numeric coprocessor is only saved when a @c
- * RTEMS_FLOATING_POINT task is dispatched and that task was not the last task
- * to utilize the coprocessor. In a system with only one @c
- * RTEMS_FLOATING_POINT task, the state of the numeric coprocessor will never
- * be saved or restored.
- *
- * Although the overhead imposed by @c RTEMS_FLOATING_POINT tasks is minimal,
- * some applications may wish to completely avoid the overhead associated with
- * @c RTEMS_FLOATING_POINT tasks and still utilize a numeric coprocessor. By
- * preventing a task from being preempted while performing a sequence of
- * floating point operations, a @c RTEMS_NO_FLOATING_POINT task can utilize
- * the numeric coprocessor without incurring the overhead of a @c
- * RTEMS_FLOATING_POINT context switch. This approach also avoids the
- * allocation of a floating point context area. However, if this approach is
- * taken by the application designer, NO tasks should be created as @c
- * RTEMS_FLOATING_POINT tasks. Otherwise, the floating point context will not
- * be correctly maintained because RTEMS assumes that the state of the numeric
- * coprocessor will not be altered by @c RTEMS_NO_FLOATING_POINT tasks.
- *
- * If the supported processor type does not have hardware floating capabilities
- * or a standard numeric coprocessor, RTEMS will not provide built-in support
- * for hardware floating point on that processor. In this case, all tasks are
- * considered @c RTEMS_NO_FLOATING_POINT whether created as @c
- * RTEMS_FLOATING_POINT or @c RTEMS_NO_FLOATING_POINT tasks. A floating point
- * emulation software library must be utilized for floating point operations.
- *
- * On some processors, it is possible to disable the floating point unit
- * dynamically. If this capability is supported by the target processor, then
- * RTEMS will utilize this capability to enable the floating point unit only
- * for tasks which are created with the @c RTEMS_FLOATING_POINT attribute.
- * The consequence of a @c RTEMS_NO_FLOATING_POINT task attempting to access
- * the floating point unit is CPU dependent but will generally result in an
- * exception condition.
- *
- * @section ClassicTasksSecPerTaskVariables Per Task Variables
- *
- * Per task variables are no longer available. In particular the
- * rtems_task_variable_add(), rtems_task_variable_get() and
- * rtems_task_variable_delete() functions are neither declared nor defined
- * anymore. Use thread local storage or POSIX Keys instead.
- *
- * @section ClassicTasksSecBuildingTaskAttributeSet Building a Task Attribute Set
- *
- * In general, an attribute set is built by a bitwise OR of the desired
- * components. The set of valid task attribute components is listed below:
- *
- * - @ref RTEMS_NO_FLOATING_POINT - does not use coprocessor (default)
- * - @ref RTEMS_FLOATING_POINT - uses numeric coprocessor
- * - @ref RTEMS_LOCAL - local task (default)
- * - @ref RTEMS_GLOBAL - global task
- *
- * Attribute values are specifically designed to be mutually exclusive,
- * therefore bitwise OR and addition operations are equivalent as long as each
- * attribute appears exactly once in the component list. A component listed as
- * a default is not required to appear in the component list, although it is a
- * good programming practice to specify default components. If all defaults are
- * desired, then @ref RTEMS_DEFAULT_ATTRIBUTES should be used. This example
- * demonstrates the attribute_set parameter needed to create a local task which
- * utilizes the numeric coprocessor. The attribute_set parameter could be @c
- * RTEMS_FLOATING_POINT or @c RTEMS_LOCAL | @c RTEMS_FLOATING_POINT. The
- * attribute_set parameter can be set to @c RTEMS_FLOATING_POINT because @c
- * RTEMS_LOCAL is the default for all created tasks. If the task were global
- * and used the numeric coprocessor, then the attribute_set parameter would be
- * @c RTEMS_GLOBAL | @c RTEMS_FLOATING_POINT.
- *
- * @section ClassicTasksSecBuildingModeAndMask Building a Mode and Mask
- *
- * In general, a mode and its corresponding mask is built by a bitwise OR of
- * the desired components. The set of valid mode constants and each mode's
- * corresponding mask constant is listed below:
- *
- * <table>
- * <tr><th>Mode Constant</th><th>Mask Constant</th><th>Description</th></tr>
- * <tr><td>@ref RTEMS_PREEMPT</td><td>@ref RTEMS_PREEMPT_MASK</td><td>enables preemption</td></tr>
- * <tr><td>@ref RTEMS_NO_PREEMPT</td><td>@ref RTEMS_PREEMPT_MASK</td><td>disables preemption</td></tr>
- * <tr><td>@ref RTEMS_NO_TIMESLICE</td><td>@ref RTEMS_TIMESLICE_MASK</td><td>disables timeslicing</td></tr>
- * <tr><td>@ref RTEMS_TIMESLICE</td><td>@ref RTEMS_TIMESLICE_MASK</td><td>enables timeslicing</td></tr>
- * <tr><td>@ref RTEMS_ASR</td><td>@ref RTEMS_ASR_MASK</td><td>enables ASR processing</td></tr>
- * <tr><td>@ref RTEMS_NO_ASR</td><td>@ref RTEMS_ASR_MASK</td><td>disables ASR processing</td></tr>
- * <tr><td>@ref RTEMS_INTERRUPT_LEVEL(0)</td><td>@ref RTEMS_INTERRUPT_MASK</td><td>enables all interrupts</td></tr>
- * <tr><td>@ref RTEMS_INTERRUPT_LEVEL(n)</td><td>@ref RTEMS_INTERRUPT_MASK</td><td>sets interrupts level n</td></tr>
- * </table>
- *
- * Mode values are specifically designed to be mutually exclusive, therefore
- * bitwise OR and addition operations are equivalent as long as each mode
- * appears exactly once in the component list. A mode component listed as a
- * default is not required to appear in the mode component list, although it is
- * a good programming practice to specify default components. If all defaults
- * are desired, the mode @ref RTEMS_DEFAULT_MODES and the mask @ref
- * RTEMS_ALL_MODE_MASKS should be used.
- *
- * The following example demonstrates the mode and mask parameters used with
- * the rtems_task_mode() directive to place a task at interrupt level 3 and
- * make it non-preemptible. The mode should be set to @c
- * RTEMS_INTERRUPT_LEVEL(3) | @c RTEMS_NO_PREEMPT to indicate the desired
- * preemption mode and interrupt level, while the mask parameter should be set
- * to @c RTEMS_INTERRUPT_MASK | @c RTEMS_PREEMPT_MASK to indicate that
- * the calling task's interrupt level and preemption mode are being altered.
- */
-
- /**
- * @defgroup LocalPackages Local Packages
- *
- * @ingroup RTEMSAPIClassic
- *
- * @brief Local packages.
- */
diff --git a/spec/build/cpukit/librtemscpu.yml b/spec/build/cpukit/librtemscpu.yml
index ff4ac8e944..14a9de009b 100644
--- a/spec/build/cpukit/librtemscpu.yml
+++ b/spec/build/cpukit/librtemscpu.yml
@@ -281,7 +281,6 @@ install:
- cpukit/include/rtems/rtems/eventimpl.h
- cpukit/include/rtems/rtems/eventmp.h
- cpukit/include/rtems/rtems/intr.h
- - cpukit/include/rtems/rtems/mainpage.h
- cpukit/include/rtems/rtems/message.h
- cpukit/include/rtems/rtems/messagedata.h
- cpukit/include/rtems/rtems/messageimpl.h
--
2.35.3
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