[rtems commit] doc/user/conf.t: Rewrite to emphasize confdefs. h and add detail

Joel Sherrill joel at rtems.org
Tue Apr 9 18:10:22 UTC 2013


Module:    rtems
Branch:    master
Commit:    6cb356713bab17edc691748675652e7754a3212f
Changeset: http://git.rtems.org/rtems/commit/?id=6cb356713bab17edc691748675652e7754a3212f

Author:    Joel Sherrill <joel.sherrill at oarcorp.com>
Date:      Sat Mar  9 07:43:03 2013 -0600

doc/user/conf.t: Rewrite to emphasize confdefs.h and add detail

This patch includes a heavy rewrite of the chapter to have a more
structured approach to this chapter.  It also changes the sectioning
to have the Data Structures be a section to themselves as a peer in the
outline with each logical area of macros in confdefs.h.

---

 doc/user/Makefile.am |    2 +-
 doc/user/conf.t      | 5654 +++++++++++++++++++++++++++++++++-----------------
 2 files changed, 3782 insertions(+), 1874 deletions(-)

diff --git a/doc/user/Makefile.am b/doc/user/Makefile.am
index 07735ff..7992b29 100644
--- a/doc/user/Makefile.am
+++ b/doc/user/Makefile.am
@@ -159,7 +159,7 @@ conf.texi: conf.t
 	    -n "Multiprocessing Manager" < $< > $@
 
 mp.texi: mp.t
-	$(BMENU2) -p "Configuring a System Unlimited Objects" \
+	$(BMENU2) -p "Configuring a System Configuration Data Structures" \
 	    -u "Top" \
 	    -n "Stack Bounds Checker" < $< > $@
 
diff --git a/doc/user/conf.t b/doc/user/conf.t
index 48cc63f..412759a 100644
--- a/doc/user/conf.t
+++ b/doc/user/conf.t
@@ -1,32 +1,36 @@
- at c  COPYRIGHT (c) 1988-2011.
+ at c  COPYRIGHT (c) 1988-2013.
 @c  On-Line Applications Research Corporation (OAR).
 @c  All rights reserved.
 
- at c The following macros from confdefs.h have not been discussed in this
- at c chapter:
- at c 
- at c CONFIGURE_NEWLIB_EXTENSION - probably not needed
- at c 
- at c In addition, there should be examples of defining your own
- at c Device Driver Table, Init task table, etc.
+ at c TODO:
+ at c   + Ensure all macros are documented.
+ at c   + Verify which structures may actually be defined by a user
+ at c   + Add Go configuration.
+
+ at c Questions:
+ at c   + Should there be examples of defining your own
+ at c     Device Driver Table, Init task table, etc.?
 @c
- at c Regardless, this is a big step up. :)
- at c 
 
 @chapter Configuring a System
 
+ at c
+ at c === Introduction ===
+ at c
 @section Introduction
 
 RTEMS must be configured for an application.  This configuration
-information encompasses a variety of information including 
+information encompasses a variety of information including
 the length of each clock tick, the maximum number of each RTEMS
 object that can be created, the application initialization tasks,
-the task scheduling algorithm to be used, 
-and the device drivers in the application.  This information
-is placed in data structures that are given to RTEMS at
-system initialization time.  This chapter details the 
-format of these data structures as well as a simpler
-mechanism to automate the generation of these structures.
+the task scheduling algorithm to be used, and the device drivers in
+the application.
+
+Although this information is contained in data structures that are used
+to RTEMS at system initialization time, the data structures themselves
+should only rarely to be generated by hand. RTEMS provides a macro based
+system which provides the standard and simple mechanism to automate the
+generation of these structures.
 
 @ifset is-Ada
 System configuration is ALWAYS done from C.  When developing
@@ -37,272 +41,2130 @@ for RTEMS System Configuration information.  Thus all examples
 and data structures shown in this chapter are in C.
 @end ifset
 
- at section Automatic Generation of System Configuration
-
 @cindex confdefs.h
 @findex confdefs.h
+ at cindex <rtems/confdefs.h>
+ at findex <rtems/confdefs.h>
+
+The RTEMS header file @code{<rtems/confdefs.h>} is the core of the
+automatic generation of system configuration. It is based on the idea
+of setting macros which define configuration parameters of interest to
+the application and defaulting or calculating all others. This variety
+of macros can automatically produce all of the configuration data
+required for an RTEMS application.
+
+Trivia: @code{confdefs} is shorthand for a @b{Configuration Defaults}.
+
+As a general rule, the application developer only specifies values
+for the configuration parameters of interest to them. They define what
+resources or features they require. In most cases, when a parameter is
+not specified, it defaults to zero (0) instances, a standards compliant
+value, or disabled as appropriate. For example, by default there will be
+256 task priority levels but this can be lowered by the application. This
+number of priority levels is required to be standards compliant.
+
+For each configuration parameter in the configuration tables, the macro
+corresponding to that field is discussed. It is expected that all systems
+can be easily configured using the @code{<rtems/confdefs.h>} mechanism. It
+is also expected that using this mechanism will avoid internal RTEMS
+configuration changes impacting applications.
+
+ at c
+ at c === Philospohy ===
+ at c
+ at section Default Value Selection Philosophy
+
+The user should be aware that the defaults are intentionally set as
+low as possible.  By default, no application resources are configured.
+The @code{<rtems/confdefs.h>} file ensures that at least one application
+tasks or thread is configured and that at least one of the initialization
+task/thread tables is configured.
+
+ at c
+ at c === Sizing the RTEMS Workspace ===
+ at c
+ at section Sizing the RTEMS Workspace
+
+The RTEMS Workspace is a user-specified block of memory reserved for
+use by RTEMS.  The application should NOT modify this memory.  This area
+consists primarily of the RTEMS data structures whose exact size depends
+upon the values specified in the Configuration Table.  In addition,
+task stacks and floating point context areas are dynamically allocated
+from the RTEMS Workspace.
+
+The @code{<rtems/confdefs.h>} mechanism calculates the size of the RTEMS
+Workspace automatically.  It assumes that all tasks are floating point and
+that all will be allocated the mininum stack space.  This calculation also
+automatically includes the memory that will be allocated for internal
+use by RTEMS. In the event, there is an under-estimation of the amount
+of memoryy required, the @code{CONFIGURE_MEMORY_OVERHEAD} is provided
+as a work-around.
+
+The starting address of the RTEMS Workspace is determined
+by the BSP must be aligned on at least a four-byte boundary.
+Failure to properly align the workspace area will result in the
+ at code{@value{DIRPREFIX}fatal_error_occurred} directive being invoked
+with the @code{@value{RPREFIX}INVALID_ADDRESS} error code.
+
+The file @code{<rtems/confdefs.h>} will calculate the value that is
+specified as the @code{work_space_size} parameter of the Configuration
+Table. There are many parameters the application developer can
+specify to help @code{<rtems/confdefs.h>} in its calculations.
+Correctly specifying the application requirements via parameters such
+as @code{CONFIGURE_EXTRA_TASK_STACKS} and @code{CONFIGURE_MAXIMUM_TASKS}
+is critical for production software.
+
+The allocation of objects can operate in two modes. The default mode
+has an object number ceiling. No more than the specified number of
+objects can be allocated from the RTEMS Workspace. The number of objects
+specified in the particular API Configuration table fields are
+allocated at initialisation. The second mode allows the number of
+objects to grow to use the available free memory in the RTEMS Workspace.
+
+See @ref{Configuring a System Unlimited Objects} for more details about
+the second mode, which allows for dynamic allocation of objects and
+therefore does not provide determinism.  This mode is useful mostly for
+when the number of objects cannot be determined ahead of time or when
+porting software for which you do not know the object requirements.
+
+Note that future versions of RTEMS may not have the same memory
+requirements per object. Although the value calculated is sufficient
+for a particular target processor and release of RTEMS, memory usage
+is subject to change across versions and target processors.  To avoid
+problems, users should accurately specify each configuration parameter and
+allow @code{<rtems/confdefs.h>} to calculate the memory requirements.
+The memory requirements are likely to change each time one of the
+following events occurs:
+
+ at itemize @bullet
+ at item a configuration parameter is modified,
+ at item task or interrupt stack requirements change,
+ at item task floating point attribute is altered,
+ at item RTEMS is upgraded, or
+ at item the target processor is changed.
+ at end itemize
+
+Failure to provide enough space in the RTEMS Workspace will result in
+the @code{@value{DIRPREFIX}fatal_error_occurred} directive being invoked
+with the appropriate error code.
+
+ at c
+ at c === Potential Issues ===
+ at c
+ at section Potential Issues with RTEMS Workspace Estimation
 
-RTEMS provides the @code{rtems/confdefs.h} C language header file that
-based on the setting of a variety of macros can automatically
-produce nearly all of the configuration tables required
-by an RTEMS application.  Rather than building the individual
-tables by hand, the application simply specifies the values
-for the configuration parameters it wishes to set.  In the following
-example, the configuration information for a simple system with
-a message queue and a time slice of 50 milliseconds is configured:
+The @code{<rtems/confdefs.h>} file estimates the amount of memory
+required for the RTEMS Workspace.  This estimate is only as accurate
+as the information given to @code{<rtems/confdefs.h>} and may be either
+too high or too low for a variety of reasons.  Some of the reasons that
+ at code{<rtems/confdefs.h>} may reserve too much memory for RTEMS are:
+
+ at itemize @bullet
+ at item All tasks/threads are assumed to be floating point.
+ at end itemize
+
+Conversely, there are many more reasons, the resource estimate could be
+too low:
+
+ at itemize @bullet
+ at item Task/thread stacks greater than minimum size must be
+accounted for explicitly by developer.
+
+ at item Memory for messages is not included.
+
+ at item Device driver requirements are not included.
+
+ at item Network stack requirements are not included.
+
+ at item Requirements for add-on libraries are not included.
+ at end itemize
+
+In general, @code{<rtems/confdefs.h>} is very accurate when given enough
+information.  However, it is quite easy to use a library and forget to
+account for its resources.
+
+ at c
+ at c === Configuration Example ===
+ at c
+ at section Configuration Example
+
+In the following example, the configuration information for a system
+with a single message queue, four (4) tasks, and a time slice
+fifty (50) milliseconds is as follows:
 
 @example
 @group
+#include <bsp.h>
+
 #define CONFIGURE_APPLICATION_NEEDS_CONSOLE_DRIVER
 #define CONFIGURE_APPLICATION_NEEDS_CLOCK_DRIVER
 
 #define CONFIGURE_MICROSECONDS_PER_TICK   1000 /* 1 millisecond */
 #define CONFIGURE_TICKS_PER_TIMESLICE       50 /* 50 milliseconds */
 
-#define CONFIGURE_MAXIMUM_TASKS 4
 #define CONFIGURE_RTEMS_INIT_TASKS_TABLE
+
+#define CONFIGURE_MAXIMUM_TASKS 4
+#define CONFIGURE_MAXIMUM_MESSAGE_QUEUES 1
+
+#define CONFIGURE_MESSAGE_BUFFER_MEMORY \
+  CONFIGURE_MESSAGE_BUFFERS_FOR_QUEUE( 10, sizeof(struct USER_MESSAGE))
+
+#define CONFIGURE_INIT
+#include <rtems/confdefs.h>
 @end group
 @end example
 
-This system will begin execution with the single initialization task
-named @code{Init}.  It will be configured to have both a console
-device driver (for standard I/O) and a clock tick device driver.
+In this example, only a few configuration parameters are specified. The
+impact of these are as follows:
 
-For each configuration parameter in the configuration tables, the
-macro corresponding to that field is discussed.  Most systems
-can be easily configured using the @code{rtems/confdefs.h} mechanism.
+ at itemize @bullet
 
-The @code{CONFIGURE_INIT} constant must be defined in order to
-make @code{rtems/confdefs.h} instantiate the configuration data
+ at item The example specified @code{CONFIGURE_RTEMS_INIT_TASK_TABLE}
+but did not specify any additional parameters. This results in a
+configuration which will begin execution at  single initialization task
+named @code{Init} which is non-preemptible and at priority one (1).
+
+ at item By specifying @code{CONFIGURE_APPLICATION_NEEDS_CLOCK_DRIVER},
+this application is configured to have a clock tick device
+driver. This is required for the passage of time including
+delays and wall time. Further configuration details about time
+are provided. Per @code{CONFIGURE_MICROSECONDS_PER_TICK} and
+ at code{CONFIGURE_TICKS_PER_TIMESLICE}, the user specified they wanted a
+clock tick to occur each millisecond, and that the length of a timeslice
+would be fifty (50) milliseconds.
+
+ at item By specifying @code{CONFIGURE_APPLICATION_NEEDS_CONSOLE_DRIVER},
+the application will include a console device driver. This provides
+for standard I/O) on at least @code{/dev/console}. Implicitly, the
+Configuration Defaults header file configures enough resources for three
+(3) file descriptors to be used for standard in, out, and error on a
+device that supports the POSIX @i{termios} interface.
+
+ at item The example above specifies via @code{CONFIGURE_MAXIMUM_TASKS},
+that the application requires a maximum of four (4)
+concurrently existent Classic API tasks. Similarly, by specifying
+ at code{CONFIGURE_MAXIMUM_MESSAGE_QUEUES}, there may be a maximum of only
+one (1) concurrently existent Classic API message queues.
+
+ at item The most surprising configuration parameter in this example is the
+use of @code{CONFIGURE_MESSAGE_BUFFER_MEMORY}. Message buffer memory is
+allocated from the RTEMS Workspace and must be accounted for. In this
+example, the single message queue will have up to twenty (20) messages
+of type @code{struct USER_MESSAGE}.
+
+ at item The @code{CONFIGURE_INIT} constant must be defined in order to
+make @code{<rtems/confdefs.h>} instantiate the configuration data
 structures.  This can only be defined in one source file per
-application that includes @code{rtems/confdefs.h} or the symbol
+application that includes @code{<rtems/confdefs.h>} or the symbol
 table will be instantiated multiple times and linking errors
 produced.
 
-The user should be aware that the defaults are intentionally
-set as low as possible.  By default, no application resources
-are configured.  The @code{rtems/confdefs.h} file ensures that
-at least one application tasks or thread is configured
-and that at least one of the initialization task/thread
-tables is configured.
-
-The @code{rtems/confdefs.h} file estimates the amount of 
-memory required for the RTEMS Executive Workspace.  This
-estimate is only as accurate as the information given
-to @code{rtems/confdefs.h} and may be either too high or too
-low for a variety of reasons.  Some of the reasons that
- at code{rtems/confdefs.h} may reserve too much memory for RTEMS
-are:
+ at end itemize
+
+This example illustrates that parameters have default values. Among
+other things, the application implicitly used the following defaults:
 
 @itemize @bullet
- at item All tasks/threads are assumed to be floating point.
+ at item All unspecified types of communications and synchronization objects
+in the Classic and POSIX Threads API have maximums of zero (0).
+
+ at item The filesystem will be the default filesystem which only supports device nodes.
+
+ at item The application will have the default number of priority levels.
+
+ at item The minimum task stack size will be that recommended by RTEMS for
+the target architecture.
 @end itemize
 
-Conversely, there are many more reasons, the resource
-estimate could be too low:
+ at c
+ at c === Unlimited Objects ===
+ at c
+ at subsection Unlimited Objects
+
+In real-time embedded systems the RAM is normally a limited, critical
+resource and dynamic allocation is avoided as much as possible to
+ensure predictable, deterministic execution times. For such cases, see
+ at ref{Configuring a System Sizing the RTEMS Workspace} for an overview
+of how to tune the size of the workspace.  Frequently when users are
+porting software to RTEMS the precise resource requirements of the
+software is unknown. In these situations users do not need to control
+the size of the workspace very tightly because they just want to get
+the new software to run; later they can tune the workspace size as needed.
+
+The following object classes in the Classic API can be configured in
+unlimited mode:
 
 @itemize @bullet
- at item Task/thread stacks greater than minimum size must be
-accounted for explicitly by developer.
+ at item Tasks
+ at item Timers
+ at item Semaphores
+ at item Message Queues
+ at item Periods
+ at item Barriers
+ at item Partitions
+ at item Regions
+ at item Ports
+ at end itemize
 
- at item Memory for messages is not included.
+Additionally, the following object classes from the POSIX API can be
+configured in unlimited mode:
 
- at item Device driver requirements are not included.
+ at itemize @bullet
+ at item Threads
+ at item Mutexes
+ at item Condition Variables
+ at item Keys
+ at item Timers
+ at item Message Queues
+ at item Message Queue Descriptors
+ at item Semaphores
+ at item Barriers
+ at item Read/Write Locks
+ at item Spinlocks
+ at end itemize
 
+Due to how the POSIX object memory requirements are configured the
+unlimited object support does not provide unlimited size declarations
+for POSIX keys or queued signals.
 
- at item Network stack requirements are not included.
+Users are cautioned that using unlimited objects is not recommended for
+production software unless the dynamic growth is absolutely required. It
+is generally considered a safer embedded systems programming practice to
+know the system limits rather than experience an out of memory error
+at an arbitrary and largely unpredictable time in the field.
 
- at item Requirements for add-on libraries are not included.
- at end itemize
+ at c
+ at c === Per Object Class Unlimited Object Instances ===
+ at c
+ at subsection Per Object Class Unlimited Object Instances
 
-In general, @code{rtems/confdefs.h} is very accurate when given
-enough information.  However, it is quite easy to use
-a library and not account for its resources.
+ at findex rtems_resource_unlimited
+When the number of objects is not known ahead of time, RTEMS provides an
+auto-extending mode that can be enabled individually for each object
+type by using the macro @code{rtems_resource_unlimited}. This takes a value
+as a parameter, and is used to set the object maximum number field in
+an API Configuration table. The value is an allocation unit size. When
+RTEMS is required to grow the object table it is grown by this
+size. The kernel will return the object memory back to the RTEMS Workspace
+when an object is destroyed. The kernel will only return an allocated
+block of objects to the RTEMS Workspace if at least half the allocation
+size of free objects remain allocated. RTEMS always keeps one
+allocation block of objects allocated. Here is an example of using
+ at code{rtems_resource_unlimited}:
 
-The following subsection list all of the constants which can be
-set by the user.
+ at example
+#define CONFIGURE_MAXIMUM_TASKS rtems_resource_unlimited(5)
+ at end example
 
- at subsection Library Support Definitions
+ at findex rtems_resource_is_unlimited
+ at findex rtems_resource_maximum_per_allocation
+Object maximum specifications can be evaluated with the
+ at code{rtems_resource_is_unlimited} and
+ at code{rtems_resource_maximum_per_allocation} macros.
 
-This section defines the file system and IO library
-related configuration parameters supported by
- at code{rtems/confdefs.h}.
+ at c
+ at c === Unlimited Object Instances ===
+ at c
+ at subsection Unlimited Object Instances
 
- at itemize @bullet
- at findex CONFIGURE_MALLOC_STATISTICS
- at item @code{CONFIGURE_MALLOC_STATISTICS} is defined when the application
-wishes to enable the gathering of more detailed statistics on the
-C Malloc Family of routines.
+To ease the burden of developers who are porting new software RTEMS
+also provides the capability to make all object classes listed above
+operate in unlimited mode in a simple manner. The application developer
+is only responsible for enabling unlimited objects and specifying the
+allocation size.
 
- at findex CONFIGURE_MALLOC_BSP_SUPPORTS_SBRK
- at item @code{CONFIGURE_MALLOC_BSP_SUPPORTS_SBRK} is defined by a BSP
-to indicate that it does not allocate all available memory to the
-C Program Heap used by the Malloc Family of routines.  If defined,
-when @code{malloc()} is unable to allocate memory, it will call
-the BSP supplied @code{sbrk()} to obtain more memory.
+ at c
+ at c === CONFIGURE_OBJECTS_UNLIMITED ===
+ at c
+ at subsection Enable Unlimited Object Instances
 
- at findex CONFIGURE_LIBIO_MAXIMUM_FILE_DESCRIPTORS
- at item @code{CONFIGURE_LIBIO_MAXIMUM_FILE_DESCRIPTORS} is set to the
-maximum number of files that can be concurrently open.  Libio requires
-a Classic RTEMS semaphore for each file descriptor as well as one 
-global one.  The default value is 3 file descriptors which is
-enough to support standard input, output, and error output.
+ at findex CONFIGURE_OBJECTS_UNLIMITED
 
- at findex CONFIGURE_TERMIOS_DISABLED
- at item @code{CONFIGURE_TERMIOS_DISABLED} is defined if the
-software implementing POSIX termios functionality is
-not going to be used by this application.  By default, this
-is not defined and resources are reserved for the
-termios functionality.
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_OBJECTS_UNLIMITED}
 
- at findex CONFIGURE_NUMBER_OF_TERMIOS_PORTS
- at item @code{CONFIGURE_NUMBER_OF_TERMIOS_PORTS} is set to the
-number of ports using the termios functionality.  Each 
-concurrently active termios port requires resources.
-By default, this is set to 1 so a console port can be
-used.
+ at item DATA TYPE:
+Boolean feature macro.
 
- at findex CONFIGURE_HAS_OWN_MOUNT_TABLE
- at item @code{CONFIGURE_HAS_OWN_MOUNT_TABLE} is defined when the
-application provides their own filesystem mount table.  The
-mount table is an array of @code{rtems_filesystem_mount_table_t}
-entries pointed to by the global variable
- at code{rtems_filesystem_mount_table}.  The number of
-entries in this table is in an integer variable named
- at code{rtems_filesystem_mount_table_t}.
+ at item RANGE:
+Defined or undefined.
 
- at findex CONFIGURE_USE_IMFS_AS_BASE_FILESYSTEM
- at item @code{CONFIGURE_USE_IMFS_AS_BASE_FILESYSTEM} is defined
-if the application wishes to use the full functionality
-IMFS.  By default, the miniIMFS is used.  The miniIMFS
-is a minimal functionality subset of the In-Memory
-FileSystem (IMFS).  The miniIMFS is comparable
-in functionality to the pseudo-filesystem name space provided 
-before RTEMS release 4.5.0.  The miniIMFS supports
-only directories and device nodes and is smaller in executable
-code size than the full IMFS.
+ at item DEFAULT VALUE:
+This is not defined by default.
 
- at findex CONFIGURE_USE_DEVFS_AS_BASE_FILESYSTEM
- at item @code{CONFIGURE_USE_DEVFS_AS_BASE_FILESYSTEM} is defined
-if the application wishes to use the device-only filesytem. The 
-device-only filesystem supports only device nodes and is smaller 
-in executable code size than the full IMFS and miniIMFS.
+ at end table
 
- at findex CONFIGURE_APPLICATION_DISABLE_FILESYSTEM
- at item @code{CONFIGURE_APPLICATION_DISABLE_FILESYSTEM} is defined
-if the application dose not intend to use any kind of filesystem
-supports(including printf family). 
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_OBJECTS_UNLIMITED} enables @code{rtems_resource_unlimited}
+mode for Classic API and POSIX API objects that do not already have a
+specific maximum limit defined.
 
+ at subheading NOTES:
+When using unlimited objects, it is common practice to also specify
+ at code{CONFIGURE_UNIFIED_WORK_AREAS} so the system operates with a single
+pool of memory for both RTEMS and application memory allocations.
 
- at findex CONFIGURE_STACK_CHECKER_ENABLED
- at item @code{CONFIGURED_STACK_CHECKER_ENABLED} is defined when
-the application wishes to enable run-time stack bounds checking.
-This increases the time required to create tasks as well as adding
-overhead to each context switch.  By default, this is not defined and
-thus stack checking is disabled.  NOTE: In 4.9 and older, this was named
- at code{STACK_CHECKER_ON}
+ at c
+ at c === CONFIGURE_OBJECTS_ALLOCATION_SIZE ===
+ at c
+ at subsection Specify Unlimited Objects Allocation Size
 
- at end itemize
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_OBJECTS_ALLOCATION_SIZE}
 
- at subsection Basic System Information
+ at item DATA TYPE:
+integer
 
-This section defines the general system configuration parameters supported by
- at code{rtems/confdefs.h}.
+ at item RANGE:
+undefined or positive
 
- at itemize @bullet
- at findex CONFIGURE_HAS_OWN_CONFIGURATION_TABLE
- at item @code{CONFIGURE_HAS_OWN_CONFIGURATION_TABLE} should only be defined
-if the application is providing their own complete set of configuration 
-tables.
+ at item DEFAULT VALUE:
+If not defined and @code{CONFIGURE_OBJECTS_UNLIMITED} is defined, the
+default value is eight (8).
 
- at findex CONFIGURE_EXECUTIVE_RAM_WORK_AREA
- at item @code{CONFIGURE_EXECUTIVE_RAM_WORK_AREA} is the base 
-address of the RTEMS RAM Workspace.  By default, this value
-is NULL indicating that the BSP is to determine the location
-of the RTEMS RAM Workspace.
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_OBJECTS_ALLOCATION_SIZE} provides an
+allocation size to use for @code{rtems_resource_unlimited} when using
+ at code{CONFIGURE_OBJECTS_UNLIMITED}.
+
+ at subheading NOTES:
+By allowing users to declare all resources as being unlimited
+the user can avoid identifying and limiting the resources used.
+ at code{CONFIGURE_OBJECTS_UNLIMITED} does not support varying the allocation
+sizes for different objects; users who want that much control can define
+the @code{rtems_resource_unlimited} macros themselves.
+
+ at example
+#define CONFIGURE_OBJECTS_UNLIMITED
+#define CONFIGURE_OBJECTS_ALLOCATION_SIZE 5
+ at end example
+
+ at c
+ at c === Classic API Configuration ===
+ at c
+ at section Classic API Configuration
+
+This section defines the Classic API related system configuration
+parameters supported by @code{<rtems/confdefs.h>}.
+
+ at c
+ at c === CONFIGURE_MAXIMUM_TASKS ===
+ at c
+ at subsection Specify Maximum Classic API Tasks
+
+ at findex CONFIGURE_MAXIMUM_TASKS
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_MAXIMUM_TASKS}
+
+ at item DATA TYPE:
+integer
+
+ at item RANGE:
+zero or positive
+
+ at item DEFAULT VALUE:
+The default for this field is 0.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_MAXIMUM_TASKS} is the maximum number of Classic API
+Tasks that can be concurrently active.
+
+ at subheading NOTES:
+This object class can be configured in unlimited allocation mode.
+
+This calculations for the required memory in the RTEMS Workspace
+for tasks assume that each task has a minimum stack size and
+has floating point support enabled.  The configuration parameter
+ at code{CONFIGURE_EXTRA_TASK_STACKS} is used to specify task stack
+requirements @b{ABOVE} the minimum size required.  See
+ at ref{Configuring a System Reserve Task/Thread Stack Memory Above Minimum}
+for more information about @code{CONFIGURE_EXTRA_TASK_STACKS}.
+
+The maximumm number of POSIX threads is specified by
+ at code{CONFIGURE_MAXIMUM_POSIX_THREADS}.
+ at c XXX - Add xref to CONFIGURE_MAXIMUM_POSIX_THREADS.
+
+A future enhancement to @code{<rtems/confdefs.h>} could be to eliminate
+the assumption that all tasks have floating point enabled. This would
+require the addition of a new configuration parameter to specify the
+number of tasks which enable floating point support.
+
+ at c
+ at c === CONFIGURE_DISABLE_CLASSIC_API_NOTEPADS ===
+ at c
+ at subsection Disable Classic API Notepads
+
+ at findex CONFIGURE_DISABLE_CLASSIC_API_NOTEPADS
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_DISABLE_CLASSIC_API_NOTEPADS}
+
+ at item DATA TYPE:
+Boolean feature macro.
+
+ at item RANGE:
+Defined or undefined.
+
+ at item DEFAULT VALUE:
+By default, this is not defined and Classic API Notepads are supported.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_DISABLE_CLASSIC_API_NOTEPADS} should be defined if the
+user does not want to have support for Classic API Notepads in their
+application.
+
+ at subheading NOTES:
+Disabling Classic API Notepads saves the allocation of sixteen (16)
+thirty-two bit integers. This saves sixty-four bytes per task/thread
+plus the allocation overhead. Notepads are rarely used in applications
+and this can save significant memory in a low RAM system.
+
+ at c
+ at c === CONFIGURE_MAXIMUM_TIMERS ===
+ at c
+ at subsection Specify Maximum Classic API Timers
+
+ at findex CONFIGURE_MAXIMUM_TIMERS
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_MAXIMUM_TIMERS}
+
+ at item DATA TYPE:
+integer
+
+ at item RANGE:
+zero or positive
+
+ at item DEFAULT VALUE:
+The default for this field is 0.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_MAXIMUM_TIMERS} is the maximum number of Classic API
+Timers that can be concurrently active.
+
+ at subheading NOTES:
+This object class can be configured in unlimited allocation mode.
+
+ at c
+ at c === CONFIGURE_MAXIMUM_SEMAPHORES ===
+ at c
+ at subsection Specify Maximum Classic API Semaphores
+
+ at findex CONFIGURE_MAXIMUM_SEMAPHORES
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_MAXIMUM_SEMAPHORES}
+
+ at item DATA TYPE:
+integer
+
+ at item RANGE:
+zero or positive
+
+ at item DEFAULT VALUE:
+The default for this field is 0.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_MAXIMUM_SEMAPHORES} is the maximum number of Classic
+API Semaphores that can be concurrently active.
+
+ at subheading NOTES:
+This object class can be configured in unlimited allocation mode.
+
+ at c
+ at c === CONFIGURE_MAXIMUM_MESSAGE_QUEUES ===
+ at c
+ at subsection Specify Maximum Classic API Message Queues
+
+ at findex CONFIGURE_MAXIMUM_MESSAGE_QUEUES
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_MAXIMUM_MESSAGE_QUEUES}
+
+ at item DATA TYPE:
+integer
+
+ at item RANGE:
+zero or positive
+
+ at item DEFAULT VALUE:
+The default for this field is 0.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_MAXIMUM_MESSAGE_QUEUES} is the maximum number of Classic
+API Message Queues that can be concurrently active.
+
+ at subheading NOTES:
+This object class can be configured in unlimited allocation mode.
+
+ at c
+ at c === CONFIGURE_MAXIMUM_BARRIERS ===
+ at c
+ at subsection Specify Maximum Classic API Barriers
+
+ at findex CONFIGURE_MAXIMUM_BARRIERS
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_MAXIMUM_BARRIERS}
+
+ at item DATA TYPE:
+integer
+
+ at item RANGE:
+zero or positive
+
+ at item DEFAULT VALUE:
+The default for this field is 0.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_MAXIMUM_BARRIERS} is the maximum number of Classic
+API Barriers that can be concurrently active.
+
+ at subheading NOTES:
+This object class can be configured in unlimited allocation mode.
+
+ at c
+ at c === CONFIGURE_MAXIMUM_PERIODS ===
+ at c
+ at subsection Specify Maximum Classic API Periods
+
+ at findex CONFIGURE_MAXIMUM_PERIODS
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_MAXIMUM_PERIODS}
+
+ at item DATA TYPE:
+integer
+
+ at item RANGE:
+zero or positive
+
+ at item DEFAULT VALUE:
+The default for this field is 0.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_MAXIMUM_PERIODS} is the maximum number of Classic
+API Periods that can be concurrently active.
+
+ at subheading NOTES:
+This object class can be configured in unlimited allocation mode.
+
+ at c
+ at c === CONFIGURE_MAXIMUM_PARTITIONS ===
+ at c
+ at subsection Specify Maximum Classic API Partitions
+
+ at findex CONFIGURE_MAXIMUM_PARTITIONS
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_MAXIMUM_PARTITIONS}
+
+ at item DATA TYPE:
+integer
+
+ at item RANGE:
+zero or positive
+
+ at item DEFAULT VALUE:
+The default for this field is 0.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_MAXIMUM_PARTITIONS} is the maximum number of Classic
+API Partitions that can be concurrently active.
+
+ at subheading NOTES:
+This object class can be configured in unlimited allocation mode.
+
+ at c
+ at c === CONFIGURE_MAXIMUM_REGIONS ===
+ at c
+ at subsection Specify Maximum Classic API Regions
+
+ at findex CONFIGURE_MAXIMUM_REGIONS
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_MAXIMUM_REGIONS}
+
+ at item DATA TYPE:
+integer
+
+ at item RANGE:
+zero or positive
+
+ at item DEFAULT VALUE:
+The default for this field is 0.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_MAXIMUM_REGIONS} is the maximum number of Classic
+API Regions that can be concurrently active.
+
+ at subheading NOTES:
+None.
+
+ at c
+ at c === CONFIGURE_MAXIMUM_PORTS ===
+ at c
+ at subsection Specify Maximum Classic API Ports
+
+ at findex CONFIGURE_MAXIMUM_PORTS
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_MAXIMUM_PORTS}
+
+ at item DATA TYPE:
+integer
+
+ at item RANGE:
+zero or positive
+
+ at item DEFAULT VALUE:
+The default for this field is 0.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_MAXIMUM_PORTS} is the maximum number of Classic
+API Ports that can be concurrently active.
+
+ at subheading NOTES:
+This object class can be configured in unlimited allocation mode.
+
+ at c
+ at c === CONFIGURE_MAXIMUM_USER_EXTENSIONS ===
+ at c
+ at subsection Specify Maximum Classic API User Extensions
+
+ at findex CONFIGURE_MAXIMUM_USER_EXTENSIONS
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_MAXIMUM_USER_EXTENSIONS}
+
+ at item DATA TYPE:
+integer
+
+ at item RANGE:
+zero or positive
+
+ at item DEFAULT VALUE:
+The default for this field is 0.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_MAXIMUM_USER_EXTENSIONS} is the maximum number of Classic
+API User Extensions that can be concurrently active.
+
+ at subheading NOTES:
+This object class can be configured in unlimited allocation mode.
+
+ at c
+ at c === Classic API Initialization Task Configuration ===
+ at c
+ at section Classic API Initialization Tasks Table Configuration
+
+The @code{<rtems/confdefs.h>} configuration system can automatically
+generate an Initialization Tasks Table named
+ at code{Initialization_tasks} with a single entry.  The following
+parameters control the generation of that table.
+
+ at c
+ at c === CONFIGURE_RTEMS_INIT_TASKS_TABLE ===
+ at c
+ at subsection Instantiate Classic API Initialization Task Table
+
+ at findex CONFIGURE_RTEMS_INIT_TASKS_TABLE
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_RTEMS_INIT_TASKS_TABLE}
+
+ at item DATA TYPE:
+Boolean feature macro.
+
+ at item RANGE:
+Defined or undefined.
+
+ at item DEFAULT VALUE:
+This is not defined by default.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_RTEMS_INIT_TASKS_TABLE} is defined if the user wishes
+to use a Classic RTEMS API Initialization Task Table. The table built by
+ at code{<rtems/confdefs.h>} specifies the parameters for a single task. This
+is sufficient for applications which initialization the system from a
+single task.
+
+By default, this field is not defined as the user MUST select their own
+API for initialization tasks.
+
+ at subheading NOTES:
+The application may choose to use the initialization tasks or threads
+table from another API.
+
+A compile time error will be generated if the user does not configure
+any initialization tasks or threads.
+
+ at c
+ at c === CONFIGURE_INIT_TASK_ENTRY_POINT ===
+ at c
+ at subsection Specifying Classic API Initialization Task Entry Point
+
+ at findex CONFIGURE_INIT_TASK_ENTRY_POINT
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_INIT_TASK_ENTRY_POINT}
+
+ at item DATA TYPE:
+rtems_task_entry
+
+ at item RANGE:
+valid method pointer
+
+ at item DEFAULT VALUE:
+By default the value is @code{Init}.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_INIT_TASK_ENTRY_POINT} is the entry point (a.k.a. function
+name) of the single initialization task defined by the Classic API
+Initialization Tasks Table.
+
+ at subheading NOTES:
+The user must implement the method @code{Init} or the method name provided
+in this configuration parameter.
+
+ at c
+ at c === CONFIGURE_INIT_TASK_NAME ===
+ at c
+ at subsection Specifying Classic API Initialization Task Name
+
+ at findex CONFIGURE_INIT_TASK_NAME
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_INIT_TASK_NAME}
+
+ at item DATA TYPE:
+rtems_name
+
+ at item RANGE:
+any value
+
+ at item DEFAULT VALUE:
+By default the value is @code{rtems_build_name( 'U', 'I', '1', ' ' )}.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_INIT_TASK_NAME} is the name of the single initialization
+task defined by the Classic API Initialization Tasks Table.
+
+ at subheading NOTES:
+None.
+
+ at c
+ at c === CONFIGURE_INIT_TASK_STACK_SIZE ===
+ at c
+ at subsection Specifying Classic API Initialization Task Stack Size
+
+ at findex CONFIGURE_INIT_TASK_STACK_SIZE
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_INIT_TASK_STACK_SIZE}
+
+ at item DATA TYPE:
+integer
+
+ at item RANGE:
+zero or positive
+
+ at item DEFAULT VALUE:
+By default value is the configured minimum stack size.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_INIT_TASK_STACK_SIZE} is the stack size of the single
+initialization task defined by the Classic API Initialization Tasks Table.
+
+ at subheading NOTES:
+If the stack size specified is greater than the configured minimum,
+it must be accounted for in @code{CONFIGURE_EXTRA_TASK_STACKS}.
+See @ref{Configuring a System Reserve Task/Thread Stack Memory Above Minimum}
+for more information about @code{CONFIGURE_EXTRA_TASK_STACKS}.
+
+ at c
+ at c === CONFIGURE_INIT_TASK_PRIORITY ===
+ at c
+ at subsection Specifying Classic API Initialization Task Priority
+
+ at findex CONFIGURE_INIT_TASK_PRIORITY
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_INIT_TASK_PRIORITY}
+
+ at item DATA TYPE:
+rtems_task_priority
+
+ at item RANGE:
+1 to CONFIGURE_MAXIMUM_PRIORITY
+
+ at item DEFAULT VALUE:
+By default the value is one (1) which is the highest priority in the
+Classic API.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_INIT_TASK_PRIORITY} is the initial priority of the single
+initialization task defined by the Classic API Initialization Tasks Table.
+
+ at subheading NOTES:
+None.
+
+ at c
+ at c === CONFIGURE_INIT_TASK_ATTRIBUTES ===
+ at c
+ at subsection Specifying Classic API Initialization Task Attributes
+
+ at findex CONFIGURE_INIT_TASK_ATTRIBUTES
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_INIT_TASK_ATTRIBUTES}
+
+
+ at item DATA TYPE:
+rtems_attributes
+
+ at item RANGE:
+valid task attribute sets
+
+ at item DEFAULT VALUE:
+By default the tvalue is @code{RTEMS_DEFAULT_ATTRIBUTES}.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_INIT_TASK_ATTRIBUTES} is the task attributes of the single
+initialization task defined by the Classic API Initialization Tasks Table.
+
+ at subheading NOTES:
+None.
+
+ at c
+ at c === CONFIGURE_INIT_TASK_INITIAL_MODES ===
+ at c
+ at subsection Specifying Classic API Initialization Task Modes
+
+ at findex CONFIGURE_INIT_TASK_INITIAL_MODES
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_INIT_TASK_INITIAL_MODES}
+
+ at item DATA TYPE:
+rtems_mode
+
+ at item RANGE:
+valid task mode sets
+
+ at item DEFAULT VALUE:
+By default the value is @code{RTEMS_NO_PREEMPT}.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_INIT_TASK_INITIAL_MODES} is the initial execution mode of
+the single initialization task defined by the Classic API Initialization
+Tasks Table.
+
+ at subheading NOTES:
+None.
+
+ at c
+ at c === CONFIGURE_INIT_TASK_ARGUMENTS ===
+ at c
+ at subsection Specifying Classic API Initialization Task Arguments
+
+ at findex CONFIGURE_INIT_TASK_ARGUMENTS
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_INIT_TASK_ARGUMENTS}
+
+ at item DATA TYPE:
+rtems_task_argument
+
+ at item RANGE:
+valid rtems_task_argument values
+
+ at item DEFAULT VALUE:
+By default the value is 0.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_INIT_TASK_ARGUMENTS} is the task argument of the single
+initialization task defined by the Classic API Initialization Tasks Table.
+
+ at subheading NOTES:
+None.
+
+ at c
+ at c === CONFIGURE_HAS_OWN_INIT_TASK_TABLE ===
+ at c
+ at subsection Not Using Generated Initialization Tasks Table
+
+ at findex CONFIGURE_HAS_OWN_INIT_TASK_TABLE
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_HAS_OWN_INIT_TASK_TABLE}
+
+ at item DATA TYPE:
+Boolean feature macro.
+
+ at item RANGE:
+Defined or undefined.
+
+ at item DEFAULT VALUE:
+This is not defined by default.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_HAS_OWN_INIT_TASK_TABLE} is defined if the user wishes
+to define their own Classic API Initialization Tasks Table.  This table
+should be named @code{Initialization_tasks}.
+
+ at subheading NOTES:
+This is a seldom used configuration parameter. The most likely use case
+is when an application desires to have more than one initialization task.
+
+ at c
+ at c === POSIX API Configuration ===
+ at c
+ at section POSIX API Configuration
+
+The parameters in this section are used to configure resources
+for the RTEMS POSIX API.  They are only relevant if the POSIX API
+is enabled at configure time using the @code{--enable-posix} option.
+
+ at c
+ at c === CONFIGURE_MAXIMUM_POSIX_THREADS ===
+ at c
+ at subsection Specify Maximum POSIX API Threads
+
+ at findex CONFIGURE_MAXIMUM_POSIX_THREADS
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_MAXIMUM_POSIX_THREADS}
+
+ at item DATA TYPE:
+integer
+
+ at item RANGE:
+zero or positive
+
+ at item DEFAULT VALUE:
+The default for this field is 0.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_MAXIMUM_POSIX_THREADS} is the maximum number of POSIX API
+Threads that can be concurrently active.
+
+ at subheading NOTES:
+This object class can be configured in unlimited allocation mode.
+
+This calculations for the required memory in the RTEMS Workspace
+for threads assume that each thread has a minimum stack size and
+has floating point support enabled.  The configuration parameter
+ at code{CONFIGURE_EXTRA_TASK_STACKS} is used to specify thread stack
+requirements @b{ABOVE} the minimum size required.
+See @ref{Configuring a System Reserve Task/Thread Stack Memory Above Minimum}
+for more information about @code{CONFIGURE_EXTRA_TASK_STACKS}.
+
+The maximum number of Classic API Tasks is specified by
+ at code{CONFIGURE_MAXIMUM_TASKS}.
+
+All POSIX threads have floating point enabled.
+
+ at c XXX - Add xref to CONFIGURE_MAXIMUM_TASKS.
+
+ at c
+ at c === CONFIGURE_MAXIMUM_POSIX_MUTEXES ===
+ at c
+ at subsection Specify Maximum POSIX API Mutexes
+
+ at findex CONFIGURE_MAXIMUM_POSIX_MUTEXES
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_MAXIMUM_POSIX_MUTEXES}
+
+ at item DATA TYPE:
+integer
+
+ at item RANGE:
+zero or positive
+
+ at item DEFAULT VALUE:
+The default for this field is 0.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_MAXIMUM_POSIX_MUTEXES} is the maximum number of POSIX
+API Mutexes that can be concurrently active.
+
+ at subheading NOTES:
+This object class can be configured in unlimited allocation mode.
+
+ at c
+ at c === CONFIGURE_MAXIMUM_POSIX_CONDITION_VARIABLES ===
+ at c
+ at subsection Specify Maximum POSIX API Condition Variables
+
+ at findex CONFIGURE_MAXIMUM_POSIX_CONDITION_VARIABLES
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_MAXIMUM_POSIX_CONDITION_VARIABLES}
+
+ at item DATA TYPE:
+integer
+
+ at item RANGE:
+zero or positive
+
+ at item DEFAULT VALUE:
+The default for this field is 0.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_MAXIMUM_POSIX_CONDITION_VARIABLES} is the maximum number
+of POSIX API Condition Variables that can be concurrently active.
+
+ at subheading NOTES:
+This object class can be configured in unlimited allocation mode.
+
+ at c
+ at c === CONFIGURE_MAXIMUM_POSIX_KEYS ===
+ at c
+ at subsection Specify Maximum POSIX API Keys
+
+ at findex CONFIGURE_MAXIMUM_POSIX_KEYS
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_MAXIMUM_POSIX_KEYS}
+
+ at item DATA TYPE:
+integer
+
+ at item RANGE:
+zero or positive
+
+ at item DEFAULT VALUE:
+The default for this field is 0.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_MAXIMUM_POSIX_KEYS} is the maximum number of POSIX
+API Keys that can be concurrently active.
+
+ at subheading NOTES:
+This object class can be configured in unlimited allocation mode.
+
+ at c XXX - Key pairs
+
+ at c
+ at c === CONFIGURE_MAXIMUM_POSIX_TIMERS ===
+ at c
+ at subsection Specify Maximum POSIX API Timers
+
+ at findex CONFIGURE_MAXIMUM_POSIX_TIMERS
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_MAXIMUM_POSIX_TIMERS}
+
+ at item DATA TYPE:
+integer
+
+ at item RANGE:
+zero or positive
+
+ at item DEFAULT VALUE:
+The default for this field is 0.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_MAXIMUM_POSIX_TIMERS} is the maximum number of POSIX
+API Timers that can be concurrently active.
+
+ at subheading NOTES:
+This object class can be configured in unlimited allocation mode.
+
+ at c
+ at c === CONFIGURE_MAXIMUM_POSIX_QUEUED_SIGNALS ===
+ at c
+ at subsection Specify Maximum POSIX API Queued Signals
+
+ at findex CONFIGURE_MAXIMUM_POSIX_QUEUED_SIGNALS
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_MAXIMUM_POSIX_QUEUED_SIGNALS}
+
+ at item DATA TYPE:
+integer
+
+ at item RANGE:
+zero or positive
+
+ at item DEFAULT VALUE:
+The default for this field is 0.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_MAXIMUM_POSIX_QUEUED_SIGNALS} is the maximum number of POSIX
+API Queued Signals that can be concurrently active.
+
+ at subheading NOTES:
+None.
+
+ at c
+ at c === CONFIGURE_MAXIMUM_POSIX_MESSAGE_QUEUES ===
+ at c
+ at subsection Specify Maximum POSIX API Message Queues
+
+ at findex CONFIGURE_MAXIMUM_POSIX_MESSAGE_QUEUES
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_MAXIMUM_POSIX_MESSAGE_QUEUES}
+
+ at item DATA TYPE:
+integer
+
+ at item RANGE:
+zero or positive
+
+ at item DEFAULT VALUE:
+The default for this field is 0.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_MAXIMUM_POSIX_MESSAGE_QUEUES} is the maximum number of POSIX
+API Message Queues that can be concurrently active.
+
+ at subheading NOTES:
+This object class can be configured in unlimited allocation mode.
+
+ at c XXX - memory for buffers note
+
+ at c
+ at c === CONFIGURE_MAXIMUM_POSIX_MESSAGE_QUEUE_DESCRIPTORS ===
+ at c
+ at subsection Specify Maximum POSIX API Message Queue Descriptors
+
+ at findex CONFIGURE_MAXIMUM_POSIX_MESSAGE_QUEUE_DESCRIPTORS
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_MAXIMUM_POSIX_MESSAGE_QUEUE_DESCRIPTORS}
+
+ at item DATA TYPE:
+integer
+
+ at item RANGE:
+greater than or equal to @code{CONFIGURE_MAXIMUM_POSIX_MESSAGES_QUEUES}
+
+ at item DEFAULT VALUE:
+The default for this field is 0.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_MAXIMUM_POSIX_MESSAGE_QUEUE_DESCRIPTORS} is the maximum
+number of POSIX API Message Queue Descriptors that can be concurrently
+active.
+
+ at subheading NOTES:
+This object class can be configured in unlimited allocation mode.
+
+ at code{CONFIGURE_MAXIMUM_POSIX_MESSAGE_QUEUE_DESCRIPTORS} should be
+greater than or equal to @code{CONFIGURE_MAXIMUM_POSIX_MESSAGE_QUEUES}.
+
+ at c
+ at c === CONFIGURE_MAXIMUM_POSIX_SEMAPHORES ===
+ at c
+ at subsection Specify Maximum POSIX API Semaphores
+
+ at findex CONFIGURE_MAXIMUM_POSIX_SEMAPHORES
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_MAXIMUM_POSIX_SEMAPHORES}
+
+ at item DATA TYPE:
+integer
+
+ at item RANGE:
+zero or positive
+
+ at item DEFAULT VALUE:
+The default for this field is 0.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_MAXIMUM_POSIX_SEMAPHORES} is the maximum number of POSIX
+API Semaphores that can be concurrently active.
+
+ at subheading NOTES:
+None.
+
+ at c
+ at c === CONFIGURE_MAXIMUM_POSIX_BARRIERS ===
+ at c
+ at subsection Specify Maximum POSIX API Barriers
+
+ at findex CONFIGURE_MAXIMUM_POSIX_BARRIERS
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_MAXIMUM_POSIX_BARRIERS}
+
+ at item DATA TYPE:
+integer
+
+ at item RANGE:
+zero or positive
+
+ at item DEFAULT VALUE:
+The default for this field is 0.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_MAXIMUM_POSIX_BARRIERS} is the maximum number of POSIX
+API Barriers that can be concurrently active.
+
+ at subheading NOTES:
+This object class can be configured in unlimited allocation mode.
+
+ at c
+ at c === CONFIGURE_MAXIMUM_POSIX_SPINLOCKS ===
+ at c
+ at subsection Specify Maximum POSIX API Spinlocks
+
+ at findex CONFIGURE_MAXIMUM_POSIX_SPINLOCKS
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_MAXIMUM_POSIX_SPINLOCKS}
+
+ at item DATA TYPE:
+integer
+
+ at item RANGE:
+zero or positive
+
+ at item DEFAULT VALUE:
+The default for this field is 0.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_MAXIMUM_POSIX_SPINLOCKS} is the maximum number of POSIX
+API Spinlocks that can be concurrently active.
+
+ at subheading NOTES:
+This object class can be configured in unlimited allocation mode.
+
+ at c
+ at c === CONFIGURE_MAXIMUM_POSIX_RWLOCKS ===
+ at c
+ at subsection Specify Maximum POSIX API Read/Write Locks
+
+ at findex CONFIGURE_MAXIMUM_POSIX_RWLOCKS
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_MAXIMUM_POSIX_RWLOCKS}
+
+ at item DATA TYPE:
+integer
+
+ at item RANGE:
+zero or positive
+
+ at item DEFAULT VALUE:
+The default for this field is 0.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_MAXIMUM_POSIX_RWLOCKS} is the maximum number of POSIX
+API Read/Write Locks that can be concurrently active.
+
+ at subheading NOTES:
+This object class can be configured in unlimited allocation mode.
+
+ at c
+ at c === POSIX Initialization Threads Table Configuration ===
+ at c
+ at section POSIX Initialization Threads Table Configuration
+
+The @code{<rtems/confdefs.h>} configuration system can automatically
+generate a POSIX Initialization Threads Table named
+ at code{POSIX_Initialization_threads} with a single entry.  The following
+parameters control the generation of that table.
+
+ at c
+ at c === CONFIGURE_POSIX_INIT_THREAD_TABLE ===
+ at c
+ at subsection Instantiate POSIX API Initialization Thread Table
+
+ at findex CONFIGURE_POSIX_INIT_THREAD_TABLE
+
+ at table @b
+ at item CONSTANT:
+ at findex CONFIGURE_POSIX_INIT_THREAD_TABLE
+
+ at item DATA TYPE:
+Boolean feature macro.
+
+ at item RANGE:
+Defined or undefined.
+
+ at item DEFAULT VALUE:
+By default, this field is not defined as the user MUST select their own
+API for initialization tasks.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_POSIX_INIT_THREAD_TABLE} is defined if the user wishes
+to use a POSIX API Initialization Threads Table.  The table built
+by @code{<rtems/confdefs.h>} specifies the parameters for a single
+thread. This is sufficient for applications which initialization the
+system from a
+single task.
+
+By default, this field is not defined as the user MUST select their own
+API for initialization tasks.
+
+ at subheading NOTES:
+The application may choose to use the initialization tasks or threads
+table from another API.
+
+A compile time error will be generated if the user does not configure
+any initialization tasks or threads.
+
+ at c
+ at c === CONFIGURE_POSIX_INIT_THREAD_ENTRY_POINT ===
+ at c
+ at subsection Specifying POSIX API Initialization Thread Entry Point
+
+ at findex CONFIGURE_POSIX_INIT_THREAD_ENTRY_POINT
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_POSIX_INIT_THREAD_ENTRY_POINT}
+
+ at item DATA TYPE:
+void *(*entry_point)(void *)
+
+ at item RANGE:
+valid method pointer
+
+ at item DEFAULT VALUE:
+By default the value is @code{POSIX_Init}.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_POSIX_INIT_THREAD_ENTRY_POINT} is the entry point
+(a.k.a. function name) of the single initialization thread defined by
+the POSIX API Initialization Threads Table.
+
+ at subheading NOTES:
+The user must implement the method @code{POSIX_Init} or the method name
+provided in this configuration parameter.
+
+ at c
+ at c === CONFIGURE_POSIX_INIT_THREAD_STACK_SIZE ===
+ at c
+ at subsection Specifying POSIX API Initialization Thread Stack Size
+
+ at findex CONFIGURE_POSIX_INIT_THREAD_STACK_SIZE
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_POSIX_INIT_THREAD_STACK_SIZE}
+
+ at item DATA TYPE:
+integer
+
+ at item RANGE:
+zero or positive
+
+ at item DEFAULT VALUE:
+By default value is twice the configured minimum stack size.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_POSIX_INIT_THREAD_STACK_SIZE} is the stack size of the
+single initialization thread defined by the POSIX API Initialization
+Threads Table.
+
+ at subheading NOTES:
+If the stack size specified is greater than the configured minimum,
+it must be accounted for in @code{CONFIGURE_EXTRA_TASK_STACKS}.
+See @ref{Configuring a System Reserve Task/Thread Stack Memory Above Minimum}
+for more information about @code{CONFIGURE_EXTRA_TASK_STACKS}.
+
+ at c
+ at c === CONFIGURE_POSIX_HAS_OWN_INIT_THREAD_TABLE ===
+ at c
+ at subsection Not Using Generated POSIX Initialization Threads Table
+
+ at findex CONFIGURE_POSIX_HAS_OWN_INIT_THREAD_TABLE
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_POSIX_HAS_OWN_INIT_THREAD_TABLE}
+
+ at item DATA TYPE:
+Boolean feature macro.
+
+ at item RANGE:
+Defined or undefined.
+
+ at item DEFAULT VALUE:
+This is not defined by default.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_POSIX_HAS_OWN_INIT_THREAD_TABLE} is defined if the
+user wishes to define their own POSIX API Initialization Threads Table.
+This table should be named @code{POSIX_Initialization_threads}.
+
+ at subheading NOTES:
+This is a seldom used configuration parameter. The most likely use case
+is when an application desires to have more than one initialization task.
+
+ at c
+ at c === Basic System Information ===
+ at c
+ at section Basic System Information
+
+This section defines the general system configuration parameters supported by
+ at code{<rtems/confdefs.h>}.
+
+ at c
+ at c === CONFIGURE_UNIFIED_WORK_AREAS ===
+ at c
+ at subsection Separate or Unified Work Areas
 
 @findex CONFIGURE_UNIFIED_WORK_AREAS
- at item @code{CONFIGURE_UNIFIED_WORK_AREAS} configures RTEMS to use a
-single memory pool for the RTEMS Workspace and C Program Heap.  If not
-defined, there will be separate memory pools for the RTEMS Workspace and
-C Program Heap.  Having separate pools does have some advantages in the
-event a task blows a stack or writes outside its memory area. However,
-in low memory systems the overhead of the two pools plus the potential
-for unused memory in either pool is very undesirable.
+ at cindex unified work areas
+ at cindex separate work areas
+ at cindex RTEMS Workspace
+ at cindex C Program Heap
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_UNIFIED_WORK_AREAS}
+
+ at item DATA TYPE:
+Boolean feature macro.
+
+ at item RANGE:
+Defined or undefined.
+
+ at item DEFAULT VALUE:
+By default, this is undefined which specifies that the C Program Heap
+and the RTEMS Workspace will be separate.
+
+ at end table
+
+ at subheading DESCRIPTION:
+When defined, the C Program Heap and the RTEMS Workspace will be one pool
+of memory.
+
+When not defined, there will be separate memory pools for the RTEMS
+Workspace and C Program Heap.
+
+ at subheading NOTES:
+Having separate pools does have some advantages in the event a task blows
+a stack or writes outside its memory area. However, in low memory systems
+the overhead of the two pools plus the potential for unused memory in
+either pool is very undesirable.
 
 In high memory environments, this is desirable when you want to use the
 RTEMS "unlimited" objects option.  You will be able to create objects
 until you run out of all available memory rather then just until you
 run out of RTEMS Workspace.
 
+ at c
+ at c === CONFIGURE_MICROSECONDS_PER_TICK ===
+ at c
+ at subsection Length of Each Clock Tick
+
 @findex CONFIGURE_MICROSECONDS_PER_TICK
- at item @code{CONFIGURE_MICROSECONDS_PER_TICK} is the length
-of time between clock ticks.  By default, this is set to
-10000 microseconds.
+ at cindex tick quantum
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_MICROSECONDS_PER_TICK}
+
+ at item DATA TYPE:
+integer
+
+ at item RANGE:
+non-zero positive values
+
+ at item DEFAULT VALUE:
+When not defined, the clock tick quantum is configured to be 10,000
+microseconds which is ten (10) milliseconds.
+
+ at end table
+
+ at subheading DESCRIPTION:
+This constant is  used to specify the length of time between clock ticks.
+
+When the clock tick quantum value is too low, the system will spend so
+much time processing clock ticks that it does not have processing time
+available to perform application work. In this case, the system will
+become unresponsive.
+
+The lowest practical time quantum varies widely based upon the speed
+of the target hardware and the architectural overhead associated with
+interrupts. In general terms, you do not want to configure it lower than
+is needed for the application.
+
+The clock tick quantum should be selected such that it all blocking and
+delay times in the application are evenly divisible by it. Otherwise,
+rounding errors will be introduced which may negatively impact the
+application.
+
+ at subheading NOTES:
+This configuration parameter has no impact if the Clock Tick Device
+driver is not configured.
+
+There may be BSP specific limits on the resolution or maximum value of
+a clock tick quantum.
+
+ at c
+ at c === CONFIGURE_TICKS_PER_TIMESLICE ===
+ at c
+ at subsection Specifying Timeslicing Quantum
 
 @findex CONFIGURE_TICKS_PER_TIMESLICE
- at item @code{CONFIGURE_TICKS_PER_TIMESLICE} is the length
-of the timeslice quantum in ticks for each task.  By
-default, this is 50.
+ at cindex ticks per timeslice
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_TICKS_PER_TIMESLICE}
+
+
+ at item DATA TYPE:
+integer
+
+ at item RANGE:
+non-zero positive values
+
+ at item DEFAULT VALUE:
+If unspecified, this parameter defaults to fifty (50).
+
+ at end table
+
+ at subheading DESCRIPTION:
+This configuration parameter specifies the length of the timeslice
+quantum in ticks for each task.
+
+ at subheading NOTES:
+This configuration parameter has no impact if the Clock Tick Device
+driver is not configured.
+
+ at c
+ at c === CONFIGURE_MAXIMUM_PRIORITY ===
+ at c
+ at subsection Specifying the Number of Thread Priority Levels
 
 @findex CONFIGURE_MAXIMUM_PRIORITY
- at item @code{CONFIGURE_MAXIMUM_PRIORITY} is the maximum numeric priority
-of any task in the system and one less that the number of priority levels
-in the system.  The numerically greatest priority is the logically lowest
-priority in the system and will thus be used by the IDLE task.  Valid values
-for this configuration parameter must be one (1) less than than a power
-of two (2) between 4 and 256 inclusively.  In other words, valid values
-are 3, 7, 31, 63, 127, and 255.  Reducing the number of priorities in the
-system reduces the amount of memory allocated from the RTEMS Workspace.
-By default, RTEMS supports 256 priority levels ranging from 0 to 255 so
+ at cindex maximum priority
+ at cindex number of priority levels
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_MAXIMUM_PRIORITY}
+
+ at item DATA TYPE:
+integer
+
+ at item RANGE:
+Valid values for this configuration parameter must be one (1) less than
+than a power of two (2) between 4 and 256 inclusively.  In other words,
+valid values are 3, 7, 31, 63, 127, and 255.
+
+ at item DEFAULT VALUE:
+By default, RTEMS must support 256 priority levels to be compliant with
+various standards. These priorities range from zero (0) to 255.  Thus,
 the default value for this field is 255.
 
- at fnindex CONFIGURE_MINIMUM_TASK_STACK_SIZE
- at item @code{CONFIGURE_MINIMUM_TASK_STACK_SIZE} is set to the number of bytes
- at fnindex CONFIGURE_MINIMUM_STACK_SIZE
- at item @code{CONFIGURE_MINIMUM_STACK_SIZE} is set to the number of bytes
-the application wants the minimum stack size to be for every task or 
-thread in the system.  By default, this is set to the recommended minimum
-stack size for this processor.
-
- at fnindex CONFIGURE_INTERRUPT_STACK_SIZE
- at item @code{CONFIGURE_INTERRUPT_STACK_SIZE} is set to the 
-size of the interrupt stack.  The interrupt stack size is
-usually set by the BSP but since this memory may be allocated
-from the RTEMS Ram Workspace, it must be accounted for.  The
-default for this field is the configured minimum stack size.  [NOTE:
+ at end table
+
+ at subheading DESCRIPTION:
+This configuration parameter specified the maximum numeric priority
+of any task in the system and one less that the number of priority levels
+in the system.
+
+Reducing the number of priorities in the system reduces the amount of
+memory allocated from the RTEMS Workspace.
+
+ at subheading NOTES:
+The numerically greatest priority is the logically lowest priority in
+the system and will thus be used by the IDLE task.
+
+Priority zero (0) is reserved for internal use by RTEMS and is not
+available to applications.
+
+With some schedulers, reducing the number of priorities can reduce the
+amount of memory used by the scheduler. For example, the Deterministic
+Priority Scheduler (DPS) used by default uses three pointers of storage
+per priority level. Reducing the number of priorities from 256 levels
+to sixteen (16) can reduce memory usage by about three (3) kilobytes.
+
+ at c
+ at c === CONFIGURE_MINIMUM_TASK_STACK_SIZE ===
+ at c
+ at subsection Specifying the Minimum Task Size
+
+ at findex CONFIGURE_MINIMUM_TASK_STACK_SIZE
+ at cindex minimum task stack size
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_MINIMUM_TASK_STACK_SIZE}
+
+ at item DATA TYPE:
+integer
+
+ at item RANGE:
+non-zero positive integer
+
+ at item DEFAULT VALUE:
+When not defined by the application, this is set to the recommended
+minimum stack size for this processor.
+
+ at end table
+
+ at subheading DESCRIPTION:
+The configuration parameter is set to the number of bytes the application
+wants the minimum stack size to be for every task or thread in the system.
+
+Adjusting this parameter should be done with caution. Examining the actual
+usage using the Stack Checker Usage Reporting facility is recommended.
+
+ at subheading NOTES:
+This parameter can be used to lower the minimum from that
+recommended. This can be used in low memory systems to reduce memory
+consumption for stacks. However, this must be done with caution as it
+could increase the possibility of a blown task stack.
+
+This parameter can be used to increase the minimum from that
+recommended. This can be used in higher memory systems to reduce the
+risk of stack overflow without performing analysis on actual consumption.
+
+ at c
+ at c === CONFIGURE_INTERRUPT_STACK_SIZE ===
+ at c
+ at subsection Configuring the Size of the Interrupt Stack
+
+ at findex CONFIGURE_INTERRUPT_STACK_SIZE
+ at cindex interrupt stack size
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_INTERRUPT_STACK_SIZE}
+
+ at item DATA TYPE:
+integer
+
+ at item RANGE:
+non-zero positive integer
+
+ at item DEFAULT VALUE:
+If not specified, the interrupt stack will be of minimum size.
+The default value is the configured minimum task stack size.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_INTERRUPT_STACK_SIZE} is set to the size of the
+interrupt stack.  The interrupt stack size is often set by the BSP but
+since this memory may be allocated from the RTEMS Workspace, it must be
+accounted for.
+
+ at subheading NOTES:
 In some BSPs, changing this constant does NOT change the
 size of the interrupt stack, only the amount of memory
-reserved for it.] If not specified, the interrupt stack
-will be of minimum size.  The default value is the configured
-minimum stack size.
+reserved for it.
 
- at findex CONFIGURE_TASK_STACK_ALLOCATOR
+Patches which result in this constant only being used in memory
+calculations when the interrupt stack is intended to be allocated
+from the RTEMS Workspace would be welcomed by the RTEMS Project.
+
+ at c
+ at c === CONFIGURE_EXTRA_TASK_STACKS ===
+ at c
+ at subsection Reserve Task/Thread Stack Memory Above Minimum
+
+ at findex CONFIGURE_EXTRA_TASK_STACKS
+ at cindex memory for task tasks
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_EXTRA_TASK_STACKS}
+
+ at item DATA TYPE:
+integer
+
+ at item RANGE:
+Undefined or positive
+
+ at item DEFAULT VALUE:
+When this is not defined, the default value is 0.
+
+ at end table
+
+ at subheading DESCRIPTION:
+This configuration parameter is set to the number of bytes the
+applications wishes to add to the task stack requirements calculated
+by @code{<rtems/confdefs.h>}.
+
+ at subheading NOTES:
+This parameter is very important.  If the application creates tasks with
+stacks larger then the minimum, then that memory is NOT accounted for
+by @code{<rtems/confdefs.h>}.
+
+ at c
+ at c === CONFIGURE_ZERO_WORKSPACE_AUTOMATICALLY ===
+ at c
+ at subsection Automatically Zeroing the RTEMS Workspace and C Program Heap
+
+ at findex CONFIGURE_ZERO_WORKSPACE_AUTOMATICALLY
+ at cindex clear C Program Heap
+ at cindex clear RTEMS Workspace
+ at cindex zero C Program Heap
+ at cindex zero RTEMS Workspace
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_ZERO_WORKSPACE_AUTOMATICALLY}
+
+ at item DATA TYPE:
+Boolean feature macro.
+
+ at item RANGE:
+Defined or undefined.
+
+ at item DEFAULT VALUE:
+Unless overridden by the BSP, this is not defined by default.  The default
+is @b{NOT} to zero out the RTEMS Workspace or C Program Heap.
+
+ at end table
+
+ at subheading DESCRIPTION:
+This macro indicates whether RTEMS should zero the RTEMS Workspace and
+C Program Heap as part of its initialization.  If defined, the memory
+regions are zeroed.  Otherwise, they are not.
+
+ at subheading NOTES:
+Zeroing memory can add significantly to system boot time. It is not
+necessary for RTEMS but is often assumed by support libraries.
+
+ at c
+ at c === CONFIGURE_STACK_CHECKER_ENABLED ===
+ at c
+ at subsection Enable The Task Stack Usage Checker
+
+ at findex CONFIGURE_STACK_CHECKER_ENABLED
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURED_STACK_CHECKER_ENABLED}
+
+ at item DATA TYPE:
+Boolean feature macro.
+
+ at item RANGE:
+Defined or undefined.
+
+ at item DEFAULT VALUE:
+By default, this is not defined and thus stack checking is disabled.
+
+ at end table
+
+ at subheading DESCRIPTION:
+This configuration parameter is defined when the application wishes to
+enable run-time stack bounds checking.
+
+
+ at subheading NOTES:
+In 4.9 and older, this configuration parameter was named
+ at code{STACK_CHECKER_ON}.
+
+This increases the time required to create tasks as well as adding
+overhead to each context switch.
+
+ at c
+ at c === CONFIGURE_INITIAL_EXTENSIONS ===
+ at c
+ at subsection Specify Application Specific User Extensions
+
+ at findex CONFIGURE_INITIAL_EXTENSIONS
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_INITIAL_EXTENSIONS}
+
+ at item DATA TYPE:
+List of @code{rtems_extensions_table} entries
+
+ at item RANGE:
+Undefined or a list of one or more user extensions.
+
+ at item DEFAULT VALUE:
+This value is not defined by default.
+
+ at end table
+
+ at subheading DESCRIPTION:
+If @code{CONFIGURE_INITIAL_EXTENSIONS} is defined by the application,
+then this application specific set of initial extensions will be placed
+in the initial extension table.
+
+ at subheading NOTES:
+None.
+
+ at c
+ at c === Custom Stack Allocator ===
+ at c
+ at section Configuring Custom Task Stack Allocation
+
+RTEMS allows the application or BSP to define its own allocation and
+deallocation methods for task stacks. This can be used to place task
+stacks in special areas of memory or to utilize a Memory Management Unit
+so that stack overflows are detected in hardware.
+
+ at c
+ at c === CONFIGURE_TASK_STACK_ALLOCATOR_INIT ===
+ at c
+ at subsection Custom Task Stack Allocator Initialization
+
+ at findex CONFIGURE_TASK_STACK_ALLOCATOR_INIT
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_TASK_STACK_ALLOCATOR_INIT}
+
+ at item DATA TYPE:
+method pointer
+
+ at item RANGE:
+NULL or valid pointer to a method
+
+ at item DEFAULT VALUE:
+The default value for this field is NULL which indicates that
+task stacks will be allocated from the RTEMS Workspace.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_TASK_STACK_ALLOCATOR_INIT} configures the initialization
+method for an application or BSP specific task stack allocation
+implementation.
+
+ at subheading NOTES:
+A correctly configured system must configure the following to be consistent:
+
+ at itemize @bullet
+ at item @code{CONFIGURE_TASK_STACK_ALLOCATOR_INIT}
 @item @code{CONFIGURE_TASK_STACK_ALLOCATOR}
-may point to a user provided routine to allocate task stacks.
+ at item @code{CONFIGURE_TASK_STACK_DEALLOCATOR}
+ at end itemize
+
+ at c
+ at c === CONFIGURE_TASK_STACK_ALLOCATOR ===
+ at c
+ at subsection Custom Task Stack Allocator
+
+ at findex CONFIGURE_TASK_STACK_ALLOCATOR
+
+ at cindex task stack allocator
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_TASK_STACK_ALLOCATOR}
+
+ at item DATA TYPE:
+method pointer
+
+ at item RANGE:
+NULL or valid method pointer
+
+ at item DEFAULT VALUE:
 The default value for this field is NULL which indicates that
 task stacks will be allocated from the RTEMS Workspace.
 
- at findex CONFIGURE_TASK_STACK_DEALLOCATOR
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_TASK_STACK_ALLOCATOR} may point to a user provided
+routine to allocate task stacks.
+
+ at subheading NOTES:
+A correctly configured system must configure the following to be consistent:
+
+ at itemize @bullet
+ at item @code{CONFIGURE_TASK_STACK_ALLOCATOR_INIT}
+ at item @code{CONFIGURE_TASK_STACK_ALLOCATOR}
 @item @code{CONFIGURE_TASK_STACK_DEALLOCATOR}
-may point to a user provided routine to free task stacks.
+ at end itemize
+
+ at c
+ at c === CONFIGURE_TASK_STACK_DEALLOCATOR ===
+ at c
+ at subsection Custom Task Stack Deallocator
+
+ at findex CONFIGURE_TASK_STACK_DEALLOCATOR
+ at cindex task stack deallocator
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_TASK_STACK_DEALLOCATOR}
+
+ at item DATA TYPE:
+method pointer
+
+ at item RANGE:
+undefined or valid pointer
+
+ at item DEFAULT VALUE:
 The default value for this field is NULL which indicates that
 task stacks will be allocated from the RTEMS Workspace.
 
- at findex CONFIGURE_ZERO_WORKSPACE_AUTOMATICALLY
- at item @code{CONFIGURE_ZERO_WORKSPACE_AUTOMATICALLY}
-indicates whether RTEMS should zero the RTEMS Workspace and
-C Program Heap as part of its initialization.  If set to
-TRUE, the Workspace is zeroed.  Otherwise, it is not.
-Unless overridden by the BSP, the default value for this
-field is FALSE.
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_TASK_STACK_DEALLOCATOR} may point to a user provided
+routine to free task stacks.
+
+ at subheading NOTES:
+A correctly configured system must configure the following to be consistent:
+
+ at itemize @bullet
+ at item @code{CONFIGURE_TASK_STACK_ALLOCATOR_INIT}
+ at item @code{CONFIGURE_TASK_STACK_ALLOCATOR}
+ at item @code{CONFIGURE_TASK_STACK_DEALLOCATOR}
+ at end itemize
+
+ at c
+ at c === Classic API Message Buffers ===
+ at c
+ at section Configuring Memory for Classic API Message Buffers
+
+This section describes the configuration parameters related to specifying
+the amount of memory reserved for Classic API Message Buffers.
+
+ at c
+ at c === CONFIGURE_MESSAGE_BUFFERS_FOR_QUEUE ===
+ at c
+ at subsection Calculate Memory for a Single Classic Message API Message Queue
 
 @findex CONFIGURE_MESSAGE_BUFFERS_FOR_QUEUE
- at item @code{CONFIGURE_MESSAGE_BUFFERS_FOR_QUEUE} is a helper macro
-which is used to assist in computing the total amount of memory
-required for message buffers.  Each message queue will have its
-own configuration with maximum message size and maximum number of
-pending messages.  The interface for this macro is as follows:
+ at cindex memory for a single message queue's buffers
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_MESSAGE_BUFFERS_FOR_QUEUE}
+
+ at item DATA TYPE:
+integer
+
+ at item RANGE:
+zero or positive
+
+ at item DEFAULT VALUE:
+This macro is only used as input to
+
+ at end table
+
+ at subheading DESCRIPTION:
+This is a helper macro which is used to assist in computing the total
+amount of memory required for message buffers.  Each message queue will
+have its own configuration with maximum message size and maximum number
+of pending messages.
+
+The interface for this macro is as follows:
 
 @example
 CONFIGURE_MESSAGE_BUFFERS_FOR_QUEUE(max_messages, size_per)
@@ -311,12 +2173,37 @@ CONFIGURE_MESSAGE_BUFFERS_FOR_QUEUE(max_messages, size_per)
 Where @code{max_messages} is the maximum number of pending messages
 and @code{size_per} is the size in bytes of the user message.
 
+ at subheading NOTES:
+This macro is only used in support of @code{CONFIGURE_MESSAGE_BUFFER_MEMORY}.
+
+ at c
+ at c === CONFIGURE_MESSAGE_BUFFER_MEMORY ===
+ at c
+ at subsection Reserve Memory for All Classic Message API Message Queues
+
 @findex CONFIGURE_MESSAGE_BUFFER_MEMORY
- at item @code{CONFIGURE_MESSAGE_BUFFER_MEMORY} is set to the number of
-bytes the application requires to be reserved for pending message queue
-buffers.  This value should include memory for all buffers across
-all APIs.  The default value is 0. 
+ at cindex configure message queue buffer memory
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_MESSAGE_BUFFER_MEMORY}
+
+ at item DATA TYPE:
+integer summation macro
 
+ at item RANGE:
+undefined (zero) or calculation resulting in a positive integer
+
+ at item DEFAULT VALUE:
+By default, this is not defined and zero (0) memory is reserved.
+
+ at end table
+
+ at subheading DESCRIPTION:
+This macro is set to the number of bytes the application requires to be
+reserved for pending Classic API Message Queue buffers.
+
+ at subheading NOTES:
 The following illustrates how the help macro
 @code{CONFIGURE_MESSAGE_BUFFERS_FOR_QUEUE} can be used to assist in
 calculating the message buffer memory required.  In this example, there
@@ -327,1980 +2214,2001 @@ has maximum of 500 pending messages with the message structure defined
 by the type @code{other_message_type}.
 
 @example
-
+ at group
 #define CONFIGURE_MESSAGE_BUFFER_MEMORY \
  (CONFIGURE_MESSAGE_BUFFERS_FOR_QUEUE( \
     24, sizeof(one_message_type) + \
   CONFIGURE_MESSAGE_BUFFERS_FOR_QUEUE( \
     500, sizeof(other_message_type) \
  )
+ at end group
 @end example
 
+ at c
+ at c === Seldom Used Configuration Parameters ===
+ at c
+ at section Seldom Used Configuration Parameters
+
+This section describes configuration parameters supported by
+ at code{<rtems/confdefs.h>} which are seldom used by applications. These
+parameters tend to be oriented to debugging system configurations
+and providing work-arounds when the memory estimated by
+ at code{<rtems/confdefs.h>} is incorrect.
+
+ at c
+ at c === CONFIGURE_MEMORY_OVERHEAD ===
+ at c
+ at subsection Specify Memory Overhead
+
 @findex CONFIGURE_MEMORY_OVERHEAD
- at item @code{CONFIGURE_MEMORY_OVERHEAD} is set to the number of
-kilobytes the application wishes to add to the requirements calculated
-by @code{rtems/confdefs.h}.  The default value is 0.
 
- at findex CONFIGURE_EXTRA_TASK_STACKS
- at item @code{CONFIGURE_EXTRA_TASK_STACKS} is set to the number of
-bytes the applications wishes to add to the task stack requirements
-calculated by @code{rtems/confdefs.h}.  This parameter is very important.
-If the application creates tasks with stacks larger then the 
-minimum, then that memory is NOT accounted for by @code{rtems/confdefs.h}.
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_MEMORY_OVERHEAD}
+
+ at item DATA TYPE:
+undefined or integer
+
+ at item RANGE:
+zero or positive
+
+ at item DEFAULT VALUE:
 The default value is 0.
 
- at end itemize
+ at end table
+
+ at subheading DESCRIPTION:
+Thie parameter is set to the number of kilobytes the application wishes
+to add to the requirements calculated by @code{<rtems/confdefs.h>}.
+
+ at subheading NOTES:
+This configuration parameter should only be used when it is suspected that
+a bug in @code{<rtems/confdefs.h>} has resulted in an underestimation.
+Typically the memory allocation will be too low when an application does
+not account for all message queue buffers or task stacks.
+
+ at c
+ at c === CONFIGURE_HAS_OWN_CONFIGURATION_TABLE ===
+ at c
+ at subsection Do Not Generate Configuration Information
+
+ at findex CONFIGURE_HAS_OWN_CONFIGURATION_TABLE
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_HAS_OWN_CONFIGURATION_TABLE}
+
+ at item DATA TYPE:
+Boolean feature macro.
+
+ at item RANGE:
+Defined or undefined.
+
+ at item DEFAULT VALUE:
+This is not defined by default.
+
+ at end table
+
+ at subheading DESCRIPTION:
+This configuration parameter should only be defined if the application
+is providing their own complete set of configuration tables.
+
+ at subheading NOTES:
+None.
+
+ at c
+ at c === CONFIGURE_EXECUTIVE_RAM_WORK_AREA ===
+ at c
+ at subsection Specify Location of RTEMS Workspace
+
+ at findex CONFIGURE_EXECUTIVE_RAM_WORK_AREA
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_EXECUTIVE_RAM_WORK_AREA}
+
+ at item DATA TYPE:
+pointer
+
+ at item RANGE:
+NULL or valid pointer
+
+ at item DEFAULT VALUE:
+By default, this value is not defined indicating that the BSP is to determine
+the location of the RTEMS Workspace.
+
+ at end table
+
+ at subheading DESCRIPTION:
+This configuration parameter is the base address of the RTEMS Workspace.
+
+ at subheading NOTES:
+The BSP is responsible for setting this address. It is highly unlikely
+that an application could do this portably and reliably.
+
+ at c
+ at c === C Library Support Configuration ===
+ at c
+ at section C Library Support Configuration
+
+This section defines the file system and IO library
+related configuration parameters supported by
+ at code{<rtems/confdefs.h>}.
+
+ at c
+ at c === CONFIGURE_MALLOC_STATISTICS ===
+ at c
+ at subsection Enable Malloc Family Statistics
+
+ at findex CONFIGURE_MALLOC_STATISTICS
+
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_MALLOC_STATISTICS}
+
+ at item DATA TYPE:
+Boolean feature macro.
+
+ at item RANGE:
+Defined or undefined.
+
+ at item DEFAULT VALUE:
+This is undefined by default and Malloc Statistics are disabled.
+
+ at end table
+
+ at subheading DESCRIPTION:
+This configuration parameter is defined when the application wishes to
+enable the gathering of more detailed statistics on the C Malloc Family
+of routines.
+
+ at subheading NOTES:
+None.
+
+ at c
+ at c === CONFIGURE_LIBIO_MAXIMUM_FILE_DESCRIPTORS ===
+ at c
+ at subsection Specify Maximum Number of File Descriptors
+
+ at findex CONFIGURE_LIBIO_MAXIMUM_FILE_DESCRIPTORS
+ at cindex maximum file descriptors
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_LIBIO_MAXIMUM_FILE_DESCRIPTORS}
+
+ at item DATA TYPE:
+integer
+
+ at item RANGE:
+Zero or positive
+
+ at item DEFAULT VALUE:
+If not defined, the default value is either zero (0) or three if
+ at code{CONFIGURE_APPLICATION_NEEDS_CONSOLE_DRIVER} is defined. Three file
+descriptors allows RTEMS to support standard input, output, and error
+I/O streams on @code{/dev/console}.
+
+ at end table
+
+ at subheading DESCRIPTION:
+This configuration parameter is set to the maximum number of files that
+can be concurrently open.
+
+ at subheading NOTES:
+In addition to the actual file descriptor data structures, the RTEMS
+Libio Support library requires a Classic API semaphore for each file
+descriptor as well as one to manage the set. Thus this configuration
+parameter implicitly impacts the configured number of Classic API
+semaphores configured for the application.
+
+ at c
+ at c === CONFIGURE_TERMIOS_DISABLED ===
+ at c
+ at subsection Disable POSIX Termios Support
+
+ at findex CONFIGURE_TERMIOS_DISABLED
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_TERMIOS_DISABLED}
+
+ at item DATA TYPE:
+Boolean feature macro.
+
+ at item RANGE:
+Defined or undefined.
+
+ at item DEFAULT VALUE:
+By default, this is not defined and resources are reserved for the
+termios functionality.
+
+ at end table
+
+ at subheading DESCRIPTION:
+This configuration parameter is defined if the software implementing
+POSIX termios functionality is not going to be used by this application.
+
+ at subheading NOTES:
+The termios support library should not be included in an application
+executable unless it is directly referenced by the application or a
+device driver.
+
+ at c
+ at c === CONFIGURE_NUMBER_OF_TERMIOS_PORTS ===
+ at c
+ at subsection Specify Maximum Termios Ports
+
+ at findex CONFIGURE_NUMBER_OF_TERMIOS_PORTS
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_NUMBER_OF_TERMIOS_PORTS}
+
+ at item DATA TYPE:
+integer
+
+ at item RANGE:
+zero or positive integer
+
+ at item DEFAULT VALUE:
+By default, this is set to 1 so a console port can be used.
+
+ at end table
+
+ at subheading DESCRIPTION:
+This configuration parameter is set to the number of ports using the
+termios functionality.  Each concurrently active termios port requires
+resources.
+
+ at subheading NOTES:
+If the application will be using serial ports
+including, but not limited to, the Console Device
+(e.g. @code{CONFIGURE_APPLICATION_NEEDS_CONSOLE_DRIVER}), then it is
+highly likely that this configuration parameter should NOT be is defined.
+
+ at c
+ at c === File System Configuration Parameters ===
+ at c
+ at section File System Configuration Parameters
+
+This section defines File System related configuration parameters.
+
+ at c
+ at c === CONFIGURE_HAS_OWN_MOUNT_TABLE ===
+ at c
+ at subsection Providing Application Specific Mount Table
+
+ at findex CONFIGURE_HAS_OWN_MOUNT_TABLE
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_HAS_OWN_MOUNT_TABLE}
+
+ at item DATA TYPE:
+Undefined or an array of type @code{rtems_filesystem_mount_table_t}.
+
+ at item RANGE:
+Undefined or an array of type @code{rtems_filesystem_mount_table_t}.
+
+ at item DEFAULT VALUE:
+This is not defined by default.
+
+ at end table
+
+ at subheading DESCRIPTION:
+This configuration parameter is defined when the application
+provides their own filesystem mount table.  The mount table is an
+array of @code{rtems_filesystem_mount_table_t} entries pointed
+to by the global variable @code{rtems_filesystem_mount_table}.
+The number of entries in this table is in an integer variable named
+ at code{rtems_filesystem_mount_table_t}.
+
+ at c XXX - is the variable name for the count right?
+
+ at subheading NOTES:
+None.
+ at c XXX - Please provide an example
+
+ at c
+ at c === CONFIGURE_USE_MINIIMFS_AS_BASE_SYSTEM ===
+ at c
+ at subsection Configure miniIMFS as Root File System
+
+ at findex CONFIGURE_USE_MINIIMFS_AS_BASE_FILESYSTEM
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_USE_MINIIMFS_AS_BASE_FILESYSTEM}
+
+ at item DATA TYPE:
+Boolean feature macro.
+
+ at item RANGE:
+Defined or undefined.
+
+ at item DEFAULT VALUE:
+
+This value is not defined by default. If no other root file system
+configuration parameters are specified, the IMFS will be used as the
+root file system.
+
+ at end table
+
+ at subheading DESCRIPTION:
+This configuration parameter is defined if the application wishes to use
+the reduced functionality miniIMFS as the root filesystem. This reduced
+version of the full IMFS does not include the capability to mount other
+file system types, but it does support directories, device nodes, and
+symbolic links.
+
+ at subheading NOTES:
+The miniIMFS nodes and is smaller in executable code size than the full IMFS.
+
+ at c
+ at c === CONFIGURE_USE_DEVFS_AS_BASE_FILESYSTEM ===
+ at c
+ at subsection Configure devFS as Root File System
+
+ at findex CONFIGURE_USE_DEVFS_AS_BASE_FILESYSTEM
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_USE_DEVFS_AS_BASE_FILESYSTEM}
+
+ at item DATA TYPE:
+Boolean feature macro.
+
+ at item RANGE:
+Defined or undefined.
+
+ at item DEFAULT VALUE:
+This value is not defined by default. If no other root file system
+configuration parameters are specified, the IMFS will be used as the
+root file system.
+
+ at end table
+
+ at subheading DESCRIPTION:
+This configuration parameter is defined if the application wishes to
+use the device-only filesytem as the root file system.
+
+ at subheading NOTES:
+The device-only filesystem supports only device nodes and is smaller in
+executable code size than the full IMFS and miniIMFS.
+
+The devFS is comparable in functionality to the pseudo-filesystem name
+space provided before RTEMS release 4.5.0.
+
+ at c
+ at c === CONFIGURE_APPLICATION_DISABLE_FILESYSTEM ===
+ at c
+ at subsection Disable File System Support
+
+ at findex CONFIGURE_APPLICATION_DISABLE_FILESYSTEM
+
+ at table @b
+ at item CONSTANT:
+
+ at item DATA TYPE:
+Boolean feature macro.
+
+ at item RANGE:
+Defined or undefined.
+
+ at item DEFAULT VALUE:
+This value is not defined by default. If no other root file system
+configuration parameters are specified, the IMFS will be used as the
+root file system.
 
-NOTE: The required size of the Executive RAM Work Area is calculated
-automatically when using the @code{rtems/confdefs.h} mechanism.
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_APPLICATION_DISABLE_FILESYSTEM}
 
- at subsection BSP Specific Settings
+ at subheading NOTES:
+This configuration parameter is defined if the application dose not
+intend to use any kind of filesystem support. This include the device
+infrastructure necessary to support @code{printf()}.
+
+ at c
+ at c === BSP Specific Settings ===
+ at c
+ at section BSP Specific Settings
 
 This section describes BSP specific configuration settings used by
- at code{<rtems/confdefs.h>}.  The BSP specific configuration settings are defined
-in @code{<bsp.h>}.
+ at code{<rtems/confdefs.h>}.  The BSP specific configuration settings are
+defined in @code{<bsp.h>}.
 
- at itemize @bullet
+ at c
+ at c === Disable BSP Settings ===
+ at c
+ at subsection Disable BSP Configuration Settings
+
+ at findex CONFIGURE_DISABLE_BSP_SETTINGS
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_DISABLE_BSP_SETTINGS}
+
+ at item DATA TYPE:
+Boolean feature macro.
+
+ at item RANGE:
+Defined or undefined.
+
+ at item DEFAULT VALUE:
+This is not defined by default.
+
+ at end table
+
+ at subheading DESCRIPTION:
+All BSP specific configuration settings can be disabled by the application
+with the @code{CONFIGURE_DISABLE_BSP_SETTINGS} option.
+
+ at subheading NOTES:
+None.
+
+ at c
+ at c === CONFIGURE_MALLOC_BSP_SUPPORTS_SBRK ===
+ at c
+ at subsection Specify BSP Supports sbrk()
+
+ at findex CONFIGURE_MALLOC_BSP_SUPPORTS_SBRK
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_MALLOC_BSP_SUPPORTS_SBRK}
+
+ at item DATA TYPE:
+Boolean feature macro.
+
+ at item RANGE:
+Defined or undefined.
+
+ at item DEFAULT VALUE:
+This configuration is undefined by default.
 
- at findex BSP_DEFAULT_UNIFIED_WORK_AREAS
- at item If @code{BSP_DEFAULT_UNIFIED_WORK_AREAS} is defined by the BSP and
- at code{CONFIGURE_UNIFIED_WORK_AREAS} is not defined by the application, then
-unified work areas will be used.
+ at end table
+
+ at subheading DESCRIPTION:
+This configuration parameter is defined by a BSP to indicate that it
+does not allocate all available memory to the C Program Heap used by
+the Malloc Family of routines.
+
+If defined, when @code{malloc()} is unable to allocate memory, it will
+call the BSP supplied @code{sbrk()} to obtain more memory.
+
+ at subheading NOTES:
+This parameter should not be defined by the application. Only the BSP
+knows how it allocates memory to the C Program Heap.
+
+ at c
+ at c === BSP_IDLE_TASK_BODY ===
+ at c
+ at subsection Specify BSP Specific Idle Task
 
 @findex BSP_IDLE_TASK_BODY
- at item If @code{BSP_IDLE_TASK_BODY} is defined by the BSP and
- at code{CONFIGURE_IDLE_TASK_BODY} is not defined by the application, then
-this BSP specific idle task body will be used.
+
+ at table @b
+ at item CONSTANT:
+ at code{BSP_IDLE_TASK_BODY}
+
+ at item DATA TYPE:
+Pointer to method.
+
+ at item RANGE:
+Null or pointer to method.
+
+ at item DEFAULT VALUE:
+This is not defined by default.
+
+ at end table
+
+ at subheading DESCRIPTION:
+If @code{BSP_IDLE_TASK_BODY} is defined by the BSP and
+ at code{CONFIGURE_IDLE_TASK_BODY} is not defined by the application,
+then this BSP specific idle task body will be used.
+
+ at subheading NOTES:
+As it has knowledge of the specific CPU model, system controller logic,
+and peripheral buses, a BSP specific IDLE task may be capable of turning
+components off to save power during extended periods of no task activity
+
+ at c
+ at c === BSP_IDLE_TASK_STACK_SIZE ===
+ at c
+ at subsection Specify BSP Suggested Value for IDLE Task Stack Size
 
 @findex BSP_IDLE_TASK_STACK_SIZE
- at item If @code{BSP_IDLE_TASK_STACK_SIZE} is defined by the BSP and
- at code{CONFIGURE_IDLE_TASK_STACK_SIZE} is not defined by the application, then
-this BSP specific idle task stack size will be used.
+
+ at table @b
+ at item CONSTANT:
+ at code{BSP_IDLE_TASK_STACK_SIZE}
+
+ at item DATA TYPE:
+integer
+
+ at item RANGE:
+undefined or positive integer
+
+ at item DEFAULT VALUE:
+This is not defined by default.
+
+ at end table
+
+ at subheading DESCRIPTION:
+If @code{BSP_IDLE_TASK_STACK_SIZE} is defined by the BSP and
+ at code{CONFIGURE_IDLE_TASK_STACK_SIZE} is not defined by the application,
+then this BSP suggested idle task stack size will be used.
+
+
+ at subheading NOTES:
+The order of precedence for configuring the IDLE task stack size is:
+
+ at itemize @bullet
+ at item RTEMS default minimum stack size.
+ at item If defined, then @code{CONFIGURE_MINIMUM_TASK_STACK_SIZE}.
+ at item If defined, then the BSP specific @code{BSP_IDLE_TASK_SIZE}.
+ at item If defined, then the application specified
+ at code{CONFIGURE_IDLE_TASK_SIZE}.
+ at end itemize
+
+ at c XXX - add cross references to other related values.
+
+ at c
+ at c === BSP_INITIAL_EXTENSION ===
+ at c
+ at subsection Specify BSP Specific User Extensions
 
 @findex BSP_INITIAL_EXTENSION
- at item If @code{BSP_INITIAL_EXTENSION} is defined by the BSP, then this BSP
+
+ at table @b
+ at item CONSTANT:
+ at code{BSP_INITIAL_EXTENSION}
+
+ at item DATA TYPE:
+List of @code{rtems_extensions_table} entries
+
+ at item RANGE:
+Undefined or a list of one or more user extensions.
+
+ at item DEFAULT VALUE:
+This value is not defined by default.
+
+ at end table
+
+ at subheading DESCRIPTION:
+If @code{BSP_INITIAL_EXTENSION} is defined by the BSP, then this BSP
 specific initial extension will be placed as the last entry in the initial
 extension table.
 
+ at subheading NOTES:
+None.
+
+ at c
+ at c === BSP_INTERRUPT_STACK_SIZE ===
+ at c
+ at subsection Specifying BSP Specific Interrupt Stack Size
+
 @findex BSP_INTERRUPT_STACK_SIZE
- at item If @code{BSP_INTERRUPT_STACK_SIZE} is defined by the BSP and
- at code{CONFIGURE_INTERRUPT_STACK_SIZE} is not defined by the application, then
-this BSP specific interrupt stack size will be used.
+
+ at table @b
+ at item CONSTANT:
+ at code{BSP_INTERRUPT_STACK_SIZE}
+
+ at item DATA TYPE:
+
+ at item RANGE:
+
+ at item DEFAULT VALUE:
+
+ at end table
+
+ at subheading DESCRIPTION:
+If @code{BSP_INTERRUPT_STACK_SIZE} is defined by the BSP and
+ at code{CONFIGURE_INTERRUPT_STACK_SIZE} is not defined by the application,
+then this BSP specific interrupt stack size will be used.
+
+ at subheading NOTES:
+None.
+
+ at c
+ at c === BSP_MAXIMUM_DEVICES ===
+ at c
+ at subsection Specifying BSP Specific Maximum Devices
 
 @findex BSP_MAXIMUM_DEVICES
- at item If @code{BSP_MAXIMUM_DEVICES} is defined by the BSP and
- at code{CONFIGURE_MAXIMUM_DEVICES} is not defined by the application, then
-this BSP specific maximum device count will be used.  This option is specific
-to the device file system (devfs) and should not be confused with the
- at code{CONFIGURE_MAXIMUM_DRIVERS} option.
+
+ at table @b
+ at item CONSTANT:
+ at code{BSP_MAXIMUM_DEVICES}
+
+ at item DATA TYPE:
+integer
+
+ at item RANGE:
+zero or positive
+
+ at item DEFAULT VALUE:
+By default, this is not defined.
+
+ at end table
+
+ at subheading DESCRIPTION:
+If @code{BSP_MAXIMUM_DEVICES} is defined by the BSP and
+ at code{CONFIGURE_MAXIMUM_DEVICES} is not defined by the application,
+then this BSP specific maximum device count will be used.  This option
+is specific to the device file system (devFS) and should not be confused
+with the @code{CONFIGURE_MAXIMUM_DRIVERS} option.
+
+ at subheading NOTES:
+This parameter only impacts the devFS and thus
+is only used by @code{<rtems/confdefs.h>} when
+ at code{CONFIGURE_USE_DEVFS_AS_BASE_FILESYSTEM} is specified.
+
+ at c
+ at c === BSP_ZERO_WORKSPACE_AUTOMATICALLY ===
+ at c
+ at subsection BSP Recommends RTEMS Workspace be Cleared
 
 @findex BSP_ZERO_WORKSPACE_AUTOMATICALLY
- at item If @code{BSP_ZERO_WORKSPACE_AUTOMATICALLY} is defined by the BSP and
+
+ at table @b
+ at item CONSTANT:
+ at code{BSP_ZERO_WORKSPACE_AUTOMATICALLY}
+
+ at item DATA TYPE:
+Boolean feature macro.
+
+ at item RANGE:
+Defined or undefined.
+
+ at item DEFAULT VALUE:
+This is not defined by default.
+
+ at end table
+
+ at subheading DESCRIPTION:
+If @code{BSP_ZERO_WORKSPACE_AUTOMATICALLY} is defined by the BSP and
 @code{CONFIGURE_ZERO_WORKSPACE_AUTOMATICALLY} is not defined by the
 application, then the workspace will be zeroed automatically.
 
+ at subheading NOTES:
+Zeroing memory can add significantly to system boot time. It is not
+necessary for RTEMS but is often assumed by support libraries.
+
+ at c
+ at c === CONFIGURE_BSP_PREREQUISITE_DRIVERS ===
+ at c
+ at subsection Specify BSP Prerequisite Drivers
+
 @findex CONFIGURE_BSP_PREREQUISITE_DRIVERS
- at item If @code{CONFIGURE_BSP_PREREQUISITE_DRIVERS} is defined by the BSP, then
-these BSP specific drivers will be placed as the first entries in the drivers
-table.  The application specific prerequisite drivers are placed after the BSP
-specific drivers.
 
- at findex CONFIGURE_MALLOC_BSP_SUPPORTS_SBRK
- at item @code{CONFIGURE_MALLOC_BSP_SUPPORTS_SBRK} is defined by the BSP to
-indicate that it does not allocate all available memory to the C Program Heap
-used by the Malloc Family of routines.  If defined, when @code{malloc()} is
-unable to allocate memory, it will call the BSP supplied @code{sbrk()} to
-obtain more memory.
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_BSP_PREREQUISITE_DRIVERS}
 
- at end itemize
+ at item DATA TYPE:
+array of device drivers
+
+ at item RANGE:
+Undefined or array of device drivers
+
+ at item DEFAULT VALUE:
+By default, this is not defined.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_BSP_PREREQUISITE_DRIVERS} is defined if the BSP has device
+drivers it needs to include in the Device Driver Table.  This should be
+defined to the set of device driver entries that will be placed in the
+table at the @b{FRONT} of the Device Driver Table and initialized before
+any other drivers @b{INCLUDING} any application prerequisite drivers.
+
+ at subheading NOTES:
+ at code{CONFIGURE_BSP_PREREQUISITE_DRIVERS} is typically used by BSPs
+to configure common infrastructure such as bus controllers or probe
+for devices.
 
-All BSP specific configuration settings can be disabled by the application with
-the @code{CONFIGURE_DISABLE_BSP_SETTINGS} option.
 
 @c
+ at c === Idle Task Configuration ===
 @c
- at c
- at subsection Idle Task Configuration
+ at section Idle Task Configuration
 
 This section defines the IDLE task related configuration parameters
-supported by @code{rtems/confdefs.h}.
+supported by @code{<rtems/confdefs.h>}.
 
- at itemize @bullet
+ at c
+ at c === CONFIGURE_IDLE_TASK_BODY ===
+ at c
+ at subsection Specify Application Specific Idle Task Body
+
+ at findex CONFIGURE_IDLE_TASK_BODY
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_IDLE_TASK_BODY}
+
+ at item DATA TYPE:
+method pointer.
+
+ at item RANGE:
+Undefined or method pointer.
+
+ at item DEFAULT VALUE:
+By default, this is not defined.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_IDLE_TASK_BODY} is set to the method name corresponding
+to the application specific IDLE thread body.  If not specified, the
+BSP or RTEMS default IDLE thread body will be used.
+
+ at subheading NOTES:
+None.
+
+ at c
+ at c === CONFIGURE_IDLE_TASK_STACK_SIZE ===
+ at c
+ at subsection Specify Idle Task Stack Size
+
+ at findex CONFIGURE_IDLE_TASK_STACK_SIZE
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_IDLE_TASK_STACK_SIZE}
+
+ at item DATA TYPE:
+integer
+
+ at item RANGE:
+undefined or positive
+
+ at item DEFAULT VALUE:
+If not specified, the IDLE task will have a stack of the configured
+minimum stack size.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_IDLE_TASK_STACK_SIZE} is set to the
+desired stack size for the IDLE task.
+
+ at subheading NOTES:
+None.
+
+ at c
+ at c === CONFIGURE_IDLE_TASK_INITIALIZES_APPLICATION ===
+ at c
+ at subsection Specify Idle Task Performs Application Initialization
+
+ at findex CONFIGURE_IDLE_TASK_INITIALIZES_APPLICATION
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_IDLE_TASK_INITIALIZES_APPLICATION}
 
- at fnindex CONFIGURE_IDLE_TASK_BODY
- at item @code{CONFIGURE_IDLE_TASK_BODY} is set to the method name
-corresponding to the application specific IDLE thread body.  If
-not specified, the BSP or RTEMS default IDLE thread body will
-be used.  The default value is NULL.
+ at item DATA TYPE:
+Boolean feature macro.
 
- at fnindex CONFIGURE_IDLE_TASK_STACK_SIZE
- at item @code{CONFIGURE_IDLE_TASK_STACK_SIZE} is set to the 
-desired stack size for the IDLE task.  If not specified,
-the IDLE task will have a stack of minimum size.  The default
-value is the configured minimum stack size.
+ at item RANGE:
+Defined or undefined.
+
+ at item DEFAULT VALUE:
+By default, this is not the mode of operation and the user is assumed
+to provide one or more initialization tasks.
+
+ at end table
 
- at fnindex CONFIGURE_IDLE_TASK_INITIALIZES_APPLICATION
- at item @code{CONFIGURE_IDLE_TASK_INITIALIZES_APPLICATION} is set to
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_IDLE_TASK_INITIALIZES_APPLICATION} is set to
 indicate that the user has configured @b{NO} user initialization tasks
 or threads and that the user provided IDLE task will perform application
-initialization and then transform itself into an IDLE task.  If you
-use this option be careful, the user IDLE task @b{CANNOT} block at
-all during the initialization sequence.  Further, once application
-initialization is complete, it must make itself preemptible and 
-enter an IDLE body loop.  By default, this is not the mode of operation
-and the user is assumed to provide one or more initialization tasks.
+initialization and then transform itself into an IDLE task.
 
- at end itemize
+ at subheading NOTES:
+If you use this option be careful, the user IDLE task @b{CANNOT} block
+at all during the initialization sequence.  Further, once application
+initialization is complete, it must make itself preemptible and enter
+an IDLE body loop.
+
+The IDLE task must run at the lowest priority of all tasks in the system.
 
 @c
+ at c === Scheduler Algorithm Configuration ===
 @c
- at c
- at subsection Scheduler Algorithm Configuration
+ at section Scheduler Algorithm Configuration
 
-This section defines the configuration parameters related to selecting 
-a scheduling algorithm for an application.  For the schedulers built into RTEMS, the configuration is straightforward.  All that is required is to define the configuration macro which specifies which scheduler you want for in your application.  The currently available schedulers are:
+This section defines the configuration parameters related to selecting a
+scheduling algorithm for an application.  For the schedulers built into
+RTEMS, the configuration is straightforward.  All that is required is
+to define the configuration macro which specifies which scheduler you
+want for in your application.  The currently available schedulers are:
 
- at itemize @bullet
+The pluggable scheduler interface also enables the user to provide their
+own scheduling algorithm.  If you choose to do this, you must define
+multiple configuration macros.
+
+ at c
+ at c === CONFIGURE_SCHEDULER_PRIORITY ===
+ at c
+ at subsection Use Deterministic Priority Scheduler
 
 @findex CONFIGURE_SCHEDULER_PRIORITY
- at item Deterministic Priority Scheduler - This is the default scheduler
-in RTEMS for single core applications and is designed for predictable
-performance under the highest loads.  It can block or unblock a thread
-in a constant amount of time.  This scheduler requires a variable
-amount of memory based upon the number of priorities configured in
-the system.  This scheduler may be explicitly selected by defining
- at code{CONFIGURE_SCHEDULER_PRIORITY}.
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_SCHEDULER_PRIORITY}
+
+ at item DATA TYPE:
+Boolean feature macro.
+
+ at item RANGE:
+Defined or undefined.
+
+ at item DEFAULT VALUE:
+This is the default scheduler and specifying this configuration parameter
+is redundant.
+
+ at end table
+
+ at subheading DESCRIPTION:
+The Deterministic Priority Scheduler is the default scheduler in RTEMS
+for single core applications and is designed for predictable performance
+under the highest loads.  It can block or unblock a thread in a constant
+amount of time.  This scheduler requires a variable amount of memory
+based upon the number of priorities configured in the system.
+
+ at subheading NOTES:
+This scheduler may be explicitly selected by defining
+ at code{CONFIGURE_SCHEDULER_PRIORITY} although this is equivalent to the
+default behavior.
+
+ at c
+ at c === CONFIGURE_SCHEDULER_SIMPLE ===
+ at c
+ at subsection Use Simple Priority Scheduler
 
 @findex CONFIGURE_SCHEDULER_SIMPLE
- at item Simple Priority Scheduler - This is an alternative scheduler
-in RTEMS.  It is designed to provide the same task scheduling behaviour
-as the Deterministic Priority Scheduler while being simpler in implementation
-and uses less memory for data management.  It maintains a single sorted list
-of all ready threads.  Thus blocking or unblocking a thread is not a
-constant time operation with this scheduler.  This scheduler is appropriate
-for use in small systems where RAM is limited.  This scheduler may be explicitly
-selected by defining @code{CONFIGURE_SCHEDULER_SIMPLE}.
 
- at findex CONFIGURE_SCHEDULER_SIMPLE_SMP
- at item Simple SMP Priority Scheduler - This scheduler is derived from the
-Simple Priority Scheduler but is capable of scheduling threads across
-multiple cores.  It is designed to provide the same task scheduling
-behaviour as the Deterministic Priority Scheduler while distributing
-threads across multiple cores.  Being based upon the Simple Priority
-Scheduler, it also maintains a single sorted list of all ready threads.
-Thus blocking or unblocking a thread is not a constant time operation
-with this scheduler.  In addition, when allocating threads to cores,
-the algorithm is not constant time.  This algorithm was not designed
-with efficiency as a primary design goal.  Its primary design goal was to
-provide an SMP-aware scheduling algorithm that is simple to understand.
-This scheduler is currently the default in SMP configurations and is
-only selected when @code{CONFIGURE_SMP_APPLICATION} is defined.  In a
-configuration with SMP enabled at configure time, it may be explicitly
-selected by defining @code{CONFIGURE_SCHEDULER_SIMPLE_SMP}.
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_SCHEDULER_SIMPLE}
+
+ at item DATA TYPE:
+Boolean feature macro.
+
+ at item RANGE:
+Defined or undefined.
+
+ at item DEFAULT VALUE:
+This is not defined by default.
+
+ at end table
+
+ at subheading DESCRIPTION:
+When defined, the Simple Priority Scheduler is used at the thread
+scheduling algorithm. This is an alternative scheduler in RTEMS.
+It is designed to provide the same task scheduling behaviour as the
+Deterministic Priority Scheduler while being simpler in implementation
+and uses less memory for data management.  It maintains a single sorted
+list of all ready threads.  Thus blocking or unblocking a thread is not
+a constant time operation with this scheduler.
+
+This scheduler may be explicitly selected by defining
+ at code{CONFIGURE_SCHEDULER_SIMPLE}.
+
+ at subheading NOTES:
+This scheduler is appropriate for use in small systems where RAM is limited.
+
+ at c
+ at c === CONFIGURE_SCHEDULER_EDF ===
+ at c
+ at subsection Use Earliest Deadline First Scheduler
 
 @findex CONFIGURE_SCHEDULER_EDF
- at item Earliest Deadline First Scheduler (EDF) - This is an alternative
-scheduler in RTEMS for single core applications. The EDF schedules tasks
-with dynamic priorities equal to deadlines. The deadlines are
-declared using only Rate Monotonic manager which handles periodic behavior.
-Period is always equal to deadline. If a task does not have any deadline
-declared or the deadline is cancelled, the task is considered a background
-task which is scheduled in case no deadline-driven tasks are ready to run.
-Moreover, multiple background tasks are scheduled according their priority
-assigned upon initialization. All ready tasks reside in a single ready queue.
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_SCHEDULER_EDF}
+
+ at item DATA TYPE:
+Boolean feature macro.
+
+ at item RANGE:
+Defined or undefined.
+
+ at item DEFAULT VALUE:
+This is not defined by default.
+
+ at end table
+
+ at subheading DESCRIPTION:
+The Earliest Deadline First Scheduler (EDF) is an alternative scheduler in
+RTEMS for single core applications. The EDF schedules tasks with dynamic
+priorities equal to deadlines. The deadlines are declared using only
+Rate Monotonic manager which handles periodic behavior.  Period is always
+equal to deadline. If a task does not have any deadline declared or the
+deadline is cancelled, the task is considered a background task which is
+scheduled in case no deadline-driven tasks are ready to run.  Moreover,
+multiple background tasks are scheduled according their priority assigned
+upon initialization. All ready tasks reside in a single ready queue.
+
 This scheduler may be explicitly selected by defining
 @code{CONFIGURE_SCHEDULER_EDF}.
 
+ at subheading NOTES:
+None.
+
+
+ at c
+ at c === CONFIGURE_SCHEDULER_CBS ===
+ at c
+ at subsection Use Constant Bandwidth Server Scheduler
+
 @findex CONFIGURE_SCHEDULER_CBS
- at item Constant Bandwidth Server Scheduler (CBS) - This is an alternative
-scheduler in RTEMS for single core applications. The CBS is a budget aware
-extention of EDF scheduler. The goal of this scheduler is to ensure temporal
-isolation of tasks. The CBS is equipped with a set of additional rules and
-provides with an extensive API. This scheduler may be explicitly selected
-by defining @code{CONFIGURE_SCHEDULER_CBS}.
 
- at end itemize
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_SCHEDULER_CBS}
+
+ at item DATA TYPE:
+Boolean feature macro.
+
+ at item RANGE:
+Defined or undefined.
+
+ at item DEFAULT VALUE:
+This is not defined by default.
+
+ at end table
+
+ at subheading DESCRIPTION:
+The Constant Bandwidth Server Scheduler (CBS) is an alternative scheduler
+in RTEMS for single core applications. The CBS is a budget aware extension
+of EDF scheduler. The goal of this scheduler is to ensure temporal
+isolation of tasks. The CBS is equipped with a set of additional rules
+and provides with an extensive API.
+
+This scheduler may be explicitly selected by defining
+ at code{CONFIGURE_SCHEDULER_CBS}.
+ at c XXX - add cross reference to API chapter
+
+ at subheading NOTES:
+None.
+
+ at c
+ at c === CONFIGURE_SCHEDULER_SIMPLE_SMP ===
+ at c
+ at subsection Use Simple SMP Priority Scheduler
 
-The pluggable scheduler interface was added after the 4.10 release series
-so there are not a lot of options at this point.  We anticipate a lower
-memory and a non-deterministic priority scheduler suitable for use in small
-systems to arrive in the future.
+ at findex CONFIGURE_SCHEDULER_SIMPLE_SMP
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_SCHEDULER_SIMPLE_SMP}
+
+ at item DATA TYPE:
+Boolean feature macro.
+
+ at item RANGE:
+Defined or undefined.
+
+ at item DEFAULT VALUE:
+This is not defined by default.
+
+ at end table
+
+ at subheading DESCRIPTION:
+The Simple SMP Priority Scheduler is derived from the Simple Priority
+Scheduler but is capable of scheduling threads across multiple cores.
+It is designed to provide the same task scheduling behaviour as the
+Deterministic Priority Scheduler while distributing threads across
+multiple cores.  Being based upon the Simple Priority Scheduler, it also
+maintains a single sorted list of all ready threads.  Thus blocking or
+unblocking a thread is not a constant time operation with this scheduler.
+
+In addition, when allocating threads to cores, the algorithm is not
+constant time. This algorithm was not designed with efficiency as a
+primary design goal.  Its primary design goal was to provide an SMP-aware
+scheduling algorithm that is simple to understand.
+
+In a configuration with SMP enabled at configure time, it may be
+explicitly selected by defining @code{CONFIGURE_SCHEDULER_SIMPLE_SMP}.
+
+ at subheading NOTES:
+This scheduler is only available when RTEMS is configured with SMP
+support enabled.
+
+This scheduler is currently the default in SMP configurations and is
+only selected when @code{CONFIGURE_SMP_APPLICATION} is defined.
 
-The pluggable scheduler interface enables the user to provide their own scheduling algorithm.  If you choose to do this, you must define multiple configuration macros.  
+ at c
+ at c === Configuring a User Scheduler ===
+ at c
+ at subsection Configuring a User Provided Scheduler
 
 @findex CONFIGURE_SCHEDULER_USER
-First, you must define @code{CONFIGURE_SCHEDULER_USER} to indicate the application provides its own scheduling algorithm. If @code{CONFIGURE_SCHEDULER_USER} is defined then the following additional macros must be defined:
 
- at itemize @bullet
- at item @code{CONFIGURE_SCHEDULER_ENTRY_POINTS} must be defined with the set of methods which implement this scheduler.  
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_SCHEDULER_USER}
+
+ at item DATA TYPE:
+Entry points for scheduler
+
+ at item RANGE:
+Undefined or scheduler entry set
+
+ at item DEFAULT VALUE:
 
+ at end table
+
+ at subheading DESCRIPTION:
+RTEMS allows the application to provide its own task/thread
+scheduling algorithm. In order to do this, one must define
+ at code{CONFIGURE_SCHEDULER_USER} to indicate the application provides its
+own scheduling algorithm. If @code{CONFIGURE_SCHEDULER_USER} is defined
+then the following additional macros must be defined:
+
+ at itemize @bullet
 @item @code{CONFIGURE_MEMORY_FOR_SCHEDULER} must be defined with the
 amount of memory required as a base amount for the scheduler.
 
 @item @code{CONFIGURE_MEMORY_PER_TASK_FOR_SCHEDULER(_tasks)} must be
-defined as a formula which computes the amount of memory required based upon the number of tasks configured.
+defined as a formula which computes the amount of memory required based
+upon the number of tasks configured.
 
 @end itemize
 
-At this time, the mechanics and requirements for writing a new
-scheduler are evolving and not fully documented.  It is recommended
-that you look at the existing Deterministic Priority Scheduler
-in @code{cpukit/score/src/schedulerpriority*.c} for guidance.
-For guidance on the configuration macros, please examine
+ at subheading NOTES:
+At this time, the mechanics and requirements for writing a
+new scheduler are evolving and not fully documented.  It is
+recommended that you look at the existing Deterministic Priority
+Scheduler in @code{cpukit/score/src/schedulerpriority*.c} for
+guidance.  For guidance on the configuration macros, please examine
 @code{cpukit/sapi/include/confdefs.h} for how these are defined for the
 Deterministic Priority Scheduler.
 
 @c
+ at c === SMP Specific Configuration Parameters ===
 @c
- at c
- at subsection SMP Specific Configuration Parameters
+ at section SMP Specific Configuration Parameters
 
 When RTEMS is configured to support SMP target systems, there are other
 configuration parameters which apply.
 
- at itemize @bullet
+ at c XXX - add --enable-smp
+
+ at c
+ at c === CONFIGURE_SMP_APPLICATION ===
+ at c
+ at subsection Specify Application Uses Multiple Cores (is SMP)
 
 @findex CONFIGURE_SMP_APPLICATION
- at item @code{CONFIGURE_SMP_APPLICATION} must be defined if the application
-is to make use of multiple CPU cores in an SMP target system.
 
- at item @code{CONFIGURE_SMP_MAXIMUM_PROCESSORS} must be set to the number
-of CPU cores in the SMP configuration.  If there are more cores available
-than configured, the rest will be ignored.
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_SMP_APPLICATION}
 
- at end itemize
+ at item DATA TYPE:
+Boolean feature macro.
+
+ at item RANGE:
+Defined or undefined.
+
+ at item DEFAULT VALUE:
+This is not defined by default.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_SMP_APPLICATION} must be defined if the application is
+to make use of multiple CPU cores in an SMP target system.
 
+ at subheading NOTES:
+None.
+
+ at c
+ at c === CONFIGURE_SMP_MAXIMUM_PROCESSORS ===
 @c
+ at subsection Specify Maximum Processors in SMP System
+
+ at findex CONFIGURE_SMP_MAXIMUM_PROCESSORS
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_SMP_MAXIMUM_PROCESSORS}
+
+ at item DATA TYPE:
+Boolean feature macro.
+
+ at item RANGE:
+Defined or undefined.
+
+ at item DEFAULT VALUE:
+This is not defined by default.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_SMP_MAXIMUM_PROCESSORS} must be set to the number of
+CPU cores in the SMP configuration.
+
+ at subheading NOTES:
+If there are more cores available than configured, the rest will be
+ignored.
+
 @c
+ at c === Device Driver Table ===
 @c
- at subsection Device Driver Table
+ at section Device Driver Table
 
 This section defines the configuration parameters related
 to the automatic generation of a Device Driver Table.  As
- at code{rtems/confdefs.h} only is aware of a small set of 
+ at code{<rtems/confdefs.h>} only is aware of a small set of
 standard device drivers, the generated Device Driver
 Table is suitable for simple applications with no
 custom device drivers.
 
- at itemize @bullet
+Note that network device drivers are not configured in the Device Driver Table.
+
+ at c
+ at c === CONFIGURE_HAS_OWN_DEVICE_DRIVER_TABLE ===
+ at c
+ at subsection Specifying Application Defined Device Driver Table
+
 @findex CONFIGURE_HAS_OWN_DEVICE_DRIVER_TABLE
- at item @code{CONFIGURE_HAS_OWN_DEVICE_DRIVER_TABLE} is defined if
-the application wishes to provide their own Device Driver Table.
-The table generated is an array of @code{rtems_driver_address_table}
-entries named @code{Device_drivers}.  By default, this is not
-defined indicating the @code{rtems/confdefs.h} is providing the
-device driver table.
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_HAS_OWN_DEVICE_DRIVER_TABLE}
+
+ at item DATA TYPE:
+Array of device drivers.
+
+ at item RANGE:
+Undefined or array of device drivers.
+
+ at item DEFAULT VALUE:
+By default, this is not defined indicating the @code{<rtems/confdefs.h>}
+is providing the device driver table.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_HAS_OWN_DEVICE_DRIVER_TABLE} is defined if the application
+wishes to provide their own Device Driver Table.
+
+The table must be an array of @code{rtems_driver_address_table} entries
+named @code{Device_drivers}.
+
+ at subheading NOTES:
+It is expected that there the application would only rarely need to do this.
+
+ at c
+ at c === CONFIGURE_MAXIMUM_DRIVERS ===
+ at c
+ at subsection Specifying the Maximum Number of Device Drivers
 
 @findex CONFIGURE_MAXIMUM_DRIVERS
- at item @code{CONFIGURE_MAXIMUM_DRIVERS} is defined
-as the number of device drivers per node.  By default, this is 
-set to 10.
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_MAXIMUM_DRIVERS}
+
+ at item DATA TYPE:
+integer
+
+ at item RANGE:
+zero or positive
+
+ at item DEFAULT VALUE:
+By default, this is set to the number of device drivers configured
+using the @code{CONFIGURE_APPLICATIONS_NEEDS_XXX_DRIVER} configuration
+parameters.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_MAXIMUM_DRIVERS} is defined as the number of device
+drivers per node.
+
+ at subheading NOTES:
+If the application will dynamically install device drivers, then this
+configuration parameter must be larger than the number of statically
+configured device drivers. Drivers configured using the
+ at code{CONFIGURE_APPLICATIONS_NEEDS_XXX_DRIVER} configuration parameters
+are statically installed.
+
+ at c
+ at c === CONFIGURE_MAXIMUM_DEVICES ===
+ at c
+ at subsection Specifying Maximum Devices
 
 @findex CONFIGURE_MAXIMUM_DEVICES
- at item @code{CONFIGURE_MAXIMUM_DEVICES} is defined
-to the number of individual devices that may be registered
-in the system.  Unless @code{BSP_MAXIMUM_DEVICES} is set
-by the BSP, the default value for this is set to 4.
-If overridden by the BSP the value is set to the value
-specified by the BSP.
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_MAXIMUM_DEVICES}
+
+ at item DATA TYPE:
+integer
+
+ at item RANGE:
+undefined or positive integer.
+
+ at item DEFAULT VALUE:
+Unless @code{BSP_MAXIMUM_DEVICES} is set by the BSP, the default value
+for this is set to 4.  If overridden by the BSP the value is set to the
+value specified by the BSP.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_MAXIMUM_DEVICES} is defined to the number of
+individual devices that may be registered in the system.
+
+ at subheading NOTES:
+This parameter only impacts the devFS and thus
+is only used by @code{<rtems/confdefs.h>} when
+ at code{CONFIGURE_USE_DEVFS_AS_BASE_FILESYSTEM} is specified.
+
+ at c
+ at c === CONFIGURE_APPLICATION_NEEDS_CONSOLE_DRIVER ===
+ at c
+ at subsection Enable Console Device Driver
 
 @findex CONFIGURE_APPLICATION_NEEDS_CONSOLE_DRIVER
+
+ at table @b
+ at item CONSTANT:
 @item @code{CONFIGURE_APPLICATION_NEEDS_CONSOLE_DRIVER}
-is defined
-if the application wishes to include the Console Device Driver.
-This device driver is responsible for providing standard input
-and output using "/dev/console".  By default, this is not
-defined.
 
- at findex CONFIGURE_APPLICATION_NEEDS_CLOCK_DRIVER
- at item @code{CONFIGURE_APPLICATION_NEEDS_CLOCK_DRIVER}
-is defined
-if the application wishes to include the Clock Device Driver.
-This device driver is responsible for providing a regular
-interrupt which invokes the @code{rtems_clock_tick} directive.
+ at item DATA TYPE:
+Boolean feature macro.
+
+ at item RANGE:
+Defined or undefined.
+
+ at item DEFAULT VALUE:
 By default, this is not defined.
 
- at findex CONFIGURE_APPLICATION_NEEDS_TIMER_DRIVER
- at item @code{CONFIGURE_APPLICATION_NEEDS_TIMER_DRIVER}
-is defined if the application wishes to include the Timer Driver.
-This device driver is used to benchmark execution times
-by the RTEMS Timing Test Suites.  By default, this is not
-defined.
+ at end table
 
- at findex CONFIGURE_APPLICATION_DOES_NOT_NEED_CLOCK_DRIVER
- at item @code{CONFIGURE_APPLICATION_DOES_NOT_NEED_CLOCK_DRIVER} is defined
-when the application does @b{NOT} want the Clock Device Driver
-and is @b{NOT} using the Timer Driver.  The inclusion or
-exclusion of the Clock Driver must be explicit in typical
-user applications.  This is intended to prevent the common
-user error of using the Hello World example as the baseline
-for an application and leaving out a clock tick source.
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_APPLICATION_NEEDS_CONSOLE_DRIVER} is defined if the
+application wishes to include the Console Device Driver.
 
- at findex CONFIGURE_APPLICATION_NEEDS_RTC_DRIVER
- at item @code{CONFIGURE_APPLICATION_NEEDS_RTC_DRIVER}
-is defined if the application wishes to include the Real-Time Clock Driver.
-By default, this is not defined.
+ at subheading NOTES:
+This device driver is responsible for providing standard input and output
+using @i{/dev/console}.
 
- at findex CONFIGURE_APPLICATION_NEEDS_WATCHDOG_DRIVER
- at item @code{CONFIGURE_APPLICATION_NEEDS_WATCHDOG_DRIVER}
-is defined if the application wishes to include the Watchdog Driver.
-By default, this is not defined.
+BSPs should be constructed in a manner that allows @code{printk()}
+to work properly without the need for the console driver to be configured.
 
- at findex CONFIGURE_APPLICATION_NEEDS_FRAME_BUFFER_DRIVER
- at item @code{CONFIGURE_APPLICATION_NEEDS_FRAME_BUFFER_DRIVER}
-is defined
-if the application wishes to include the BSP's Frame Buffer Device Driver.
-Most BSPs do not provide a Frame Buffer Device Driver.  If this is
-defined and the BSP does not have this device driver, then the user
-will get a link time error for an undefined symbol.
-By default, this is not defined.
+ at c
+ at c === CONFIGURE_APPLICATION_NEEDS_CLOCK_DRIVER ===
+ at c
+ at subsection Enable Clock Driver
 
- at findex CONFIGURE_APPLICATION_NEEDS_STUB_DRIVER
- at item @code{CONFIGURE_APPLICATION_NEEDS_STUB_DRIVER}
-is defined if the application wishes to include the Stub Device Driver.
-This device driver simply provides entry points that return
-successful and is primarily a test fixture.
-By default, this is not defined.
+ at findex CONFIGURE_APPLICATION_NEEDS_CLOCK_DRIVER
 
- at findex CONFIGURE_BSP_PREREQUISITE_DRIVERS
- at item @code{CONFIGURE_BSP_PREREQUISITE_DRIVERS} is defined if the
-BSP has device drivers it needs to include in the Device Driver
-Table.  This should be defined to the set of device driver entries that
-will be placed in the table at the @b{FRONT} of the Device Driver Table
-and initialized before any other drivers @b{INCLUDING} any application
-prerequisite drivers.  By default,this is not defined.
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_APPLICATION_NEEDS_CLOCK_DRIVER}
 
- at findex CONFIGURE_APPLICATION_PREREQUISITE_DRIVERS
- at item @code{CONFIGURE_APPLICATION_PREREQUISITE_DRIVERS} is defined if the
-application has device drivers it needs to include in the Device Driver
-Table.  This should be defined to the set of device driver entries that
-will be placed in the table at the @b{FRONT} of the Device Driver Table
-and initialized before any other drivers @b{EXCEPT} any BSP prerequisite
-drivers.  By default,this is not defined.
+ at item DATA TYPE:
+Boolean feature macro.
 
- at findex CONFIGURE_APPLICATION_EXTRA_DRIVERS
- at item @code{CONFIGURE_APPLICATION_EXTRA_DRIVERS} is defined if the
-application has device drivers it needs to include in the Device Driver
-Table.  This should be defined to the set of device driver entries that
-will be placed in the table at the @b{END} of the Device Driver Table.
-By default,this is not defined.
+ at item RANGE:
+Defined or undefined.
 
- at end itemize
+ at item DEFAULT VALUE:
+By default, this is not defined.
 
- at subsection Multiprocessing Configuration
+ at end table
 
-This section defines the multiprocessing related
-system configuration parameters supported by @code{rtems/confdefs.h}.
-This class of Configuration Constants are only applicable if
- at code{CONFIGURE_MP_APPLICATION} is defined.
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_APPLICATION_NEEDS_CLOCK_DRIVER} is defined if the
+application wishes to include the Clock Device Driver.
 
- at itemize @bullet
- at findex CONFIGURE_HAS_OWN_MULTIPROCESSING_TABLE
- at item @code{CONFIGURE_HAS_OWN_MULTIPROCESSING_TABLE} is defined
-if the application wishes to provide their own Multiprocessing
-Configuration Table.  The generated table is named
- at code{Multiprocessing_configuration}.  By default, this
-is not defined.
+ at subheading NOTES:
+This device driver is responsible for providing a regular
+interrupt which invokes the @code{rtems_clock_tick} directive.
 
- at findex CONFIGURE_MP_NODE_NUMBER
- at item @code{CONFIGURE_MP_NODE_NUMBER} is the node number of
-this node in a multiprocessor system.  The default node number
-is @code{NODE_NUMBER} which is set directly in RTEMS test Makefiles.
+If neither the Clock Driver not Benchmark Timer is enabled and
+the configuration parameter
+ at code{CONFIGURE_APPLICATION_DOES_NOT_NEED_CLOCK_DRIVER} is not defined,
+then a compile time error will occur.
 
- at findex CONFIGURE_MP_MAXIMUM_NODES
- at item @code{CONFIGURE_MP_MAXIMUM_NODES} is the maximum number
-of nodes in a multiprocessor system.  The default is 2.
+ at c
+ at c === CONFIGURE_APPLICATION_NEEDS_TIMER_DRIVER ===
+ at c
+ at subsection Enable the Benchmark Timer Driver
 
- at findex CONFIGURE_MP_MAXIMUM_GLOBAL_OBJECTS
- at item @code{CONFIGURE_MP_MAXIMUM_GLOBAL_OBJECTS}
-is the maximum number
-of concurrently active global objects in a multiprocessor
-system.  The default is 32.
+ at findex CONFIGURE_APPLICATION_NEEDS_TIMER_DRIVER
 
- at findex CONFIGURE_MP_MAXIMUM_PROXIES
- at item @code{CONFIGURE_MP_MAXIMUM_PROXIES} is the maximum number
-of concurrently active thread/task proxies in a multiprocessor
-system.  The default is 32.
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_APPLICATION_NEEDS_TIMER_DRIVER}
 
- at findex CONFIGURE_MP_MPCI_TABLE_POINTER
- at item @code{CONFIGURE_MP_MPCI_TABLE_POINTER} is the pointer
-to the MPCI Configuration Table.  The default value of
-this field is @code{&MPCI_table}.
- at end itemize
+ at item DATA TYPE:
+Boolean feature macro.
 
- at subsection Classic API Configuration
+ at item RANGE:
+Defined or undefined.
 
-This section defines the Classic API related
-system configuration parameters supported by @code{rtems/confdefs.h}.
+ at item DEFAULT VALUE:
+By default, this is not defined.
 
- at itemize @bullet
- at findex CONFIGURE_MAXIMUM_TASKS
- at item @code{CONFIGURE_MAXIMUM_TASKS} is the maximum number of
-Classic API tasks that can be concurrently active. 
-The default for this field is 0.
+ at end table
 
- at findex CONFIGURE_DISABLE_CLASSIC_API_NOTEPADS
- at item @code{CONFIGURE_DISABLE_CLASSIC_API_NOTEPADS} should be defined
-if the user does not want to have support for Classic API Notepads
-in their application.  By default, this is not defined and Classic API
-Notepads are supported.
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_APPLICATION_NEEDS_TIMER_DRIVER} is defined if the
+application wishes to include the Timer Driver.  This device driver is
+used to benchmark execution times by the RTEMS Timing Test Suites.
 
- at findex CONFIGURE_MAXIMUM_TIMERS
- at item @code{CONFIGURE_MAXIMUM_TIMERS} is the maximum number of
-Classic API timers that can be concurrently active. 
-The default for this field is 0.
+ at subheading NOTES:
+If neither the Clock Driver not Benchmark Timer is enabled and
+the configuration parameter
+ at code{CONFIGURE_APPLICATION_DOES_NOT_NEED_CLOCK_DRIVER} is not defined,
+then a compile time error will occur.
 
- at findex CONFIGURE_MAXIMUM_SEMAPHORES
- at item @code{CONFIGURE_MAXIMUM_SEMAPHORES} is the maximum number of
-Classic API semaphores that can be concurrently active. 
-The default for this field is 0.
+ at c
+ at c === CONFIGURE_APPLICATION_DOES_NOT_NEED_CLOCK_DRIVER ===
+ at c
+ at subsection Specify Clock and Benchmark Timer Drivers Are Not Needed
 
- at findex CONFIGURE_MAXIMUM_MESSAGE_QUEUES
- at item @code{CONFIGURE_MAXIMUM_MESSAGE_QUEUES} is the maximum number of
-Classic API message queues that can be concurrently active. 
-The default for this field is 0.
+ at findex CONFIGURE_APPLICATION_DOES_NOT_NEED_CLOCK_DRIVER
 
- at findex CONFIGURE_MAXIMUM_PARTITIONS
- at item @code{CONFIGURE_MAXIMUM_PARTITIONS} is the maximum number of
-Classic API partitions that can be concurrently active. 
-The default for this field is 0.
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_APPLICATION_DOES_NOT_NEED_CLOCK_DRIVER}
 
- at findex CONFIGURE_MAXIMUM_REGIONS
- at item @code{CONFIGURE_MAXIMUM_REGIONS} is the maximum number of
-Classic API regions that can be concurrently active. 
-The default for this field is 0.
+ at item DATA TYPE:
+Boolean feature macro.
 
- at findex CONFIGURE_MAXIMUM_PORTS
- at item @code{CONFIGURE_MAXIMUM_PORTS} is the maximum number of
-Classic API ports that can be concurrently active. 
-The default for this field is 0.
+ at item RANGE:
+Defined or undefined.
 
- at findex CONFIGURE_MAXIMUM_PERIODS
- at item @code{CONFIGURE_MAXIMUM_PERIODS} is the maximum number of
-Classic API rate monotonic periods that can be concurrently active. 
-The default for this field is 0.
+ at item DEFAULT VALUE:
+This is not defined by default.
 
- at findex CONFIGURE_MAXIMUM_USER_EXTENSIONS
- at item @code{CONFIGURE_MAXIMUM_USER_EXTENSIONS} is the maximum number of
-Classic API user extensions that can be concurrently active. 
-The default for this field is 0.
+ at end table
 
- at end itemize
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_APPLICATION_DOES_NOT_NEED_CLOCK_DRIVER} is defined when
+the application does @b{NOT} want the Clock Device Driver and is @b{NOT}
+using the Timer Driver.  The inclusion or exclusion of the Clock Driver
+must be explicit in user applications.
 
- at subsection Classic API Initialization Tasks Table Configuration
+ at subheading NOTES:
+This configuration parameter is intended to prevent the common user error
+of using the Hello World example as the baseline for an application and
+leaving out a clock tick source.
 
-The @code{rtems/confdefs.h} configuration system can automatically
-generate an Initialization Tasks Table named 
- at code{Initialization_tasks} with a single entry.  The following
-parameters control the generation of that table.
+ at c
+ at c === CONFIGURE_APPLICATION_NEEDS_RTC_DRIVER ===
+ at c
+ at subsection Enable Real-Time Clock Driver
 
- at itemize @bullet
- at findex CONFIGURE_RTEMS_INIT_TASKS_TABLE
- at item @code{CONFIGURE_RTEMS_INIT_TASKS_TABLE} is defined
-if the user wishes to use a Classic RTEMS API Initialization
-Task Table.  The application may choose to use the initialization
-tasks or threads table from another API.  By default, this
-field is not defined as the user MUST select their own
-API for initialization tasks.
+ at findex CONFIGURE_APPLICATION_NEEDS_RTC_DRIVER
 
- at findex CONFIGURE_HAS_OWN_INIT_TASK_TABLE
- at item @code{CONFIGURE_HAS_OWN_INIT_TASK_TABLE} is defined
-if the user wishes to define their own Classic API Initialization
-Tasks Table.  This table should be named @code{Initialization_tasks}.
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_APPLICATION_NEEDS_RTC_DRIVER}
+
+ at item DATA TYPE:
+Boolean feature macro.
+
+ at item RANGE:
+Defined or undefined.
+
+ at item DEFAULT VALUE:
 By default, this is not defined.
 
- at findex CONFIGURE_INIT_TASK_NAME
- at item @code{CONFIGURE_INIT_TASK_NAME} is the name
-of the single initialization task defined by the
-Classic API Initialization Tasks Table.  By default
-the value is @code{rtems_build_name( 'U', 'I', '1', ' ' )}.
+ at end table
 
- at findex CONFIGURE_INIT_TASK_STACK_SIZE
- at item @code{CONFIGURE_INIT_TASK_STACK_SIZE}
-is the stack size
-of the single initialization task defined by the
-Classic API Initialization Tasks Table.  By default
-value is the configured minimum stack size.
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_APPLICATION_NEEDS_RTC_DRIVER} is defined if the
+application wishes to include the Real-Time Clock Driver.
 
- at findex CONFIGURE_INIT_TASK_PRIORITY
- at item @code{CONFIGURE_INIT_TASK_PRIORITY}
-is the initial priority
-of the single initialization task defined by the
-Classic API Initialization Tasks Table.  By default
-the value is 1 which is the highest priority
-in the Classic API.
+ at subheading NOTES:
+Most BSPs do not include support for a real-time clock. This is because
+many boards do not include the required hardware.
 
- at findex CONFIGURE_INIT_TASK_ATTRIBUTES
- at item @code{CONFIGURE_INIT_TASK_ATTRIBUTES}
-is the task attributes
-of the single initialization task defined by the
-Classic API Initialization Tasks Table.  By default
-the value is @code{RTEMS_DEFAULT_ATTRIBUTES}.
+If this is defined and the BSP does not have this device driver, then
+the user will get a link time error for an undefined symbol.
 
- at findex CONFIGURE_INIT_TASK_ENTRY_POINT
- at item @code{CONFIGURE_INIT_TASK_ENTRY_POINT}
-is the entry point (a.k.a. function name)
-of the single initialization task defined by the
-Classic API Initialization Tasks Table.  By default
-the value is @code{Init}.
+ at c
+ at c === CONFIGURE_APPLICATION_NEEDS_WATCHDOG_DRIVER ===
+ at c
+ at subsection Enable the Watchdog Device Driver
 
- at findex CONFIGURE_INIT_TASK_INITIAL_MODES
- at item @code{CONFIGURE_INIT_TASK_INITIAL_MODES}
-is the initial execution mode
-of the single initialization task defined by the
-Classic API Initialization Tasks Table.  By default
-the value is @code{RTEMS_NO_PREEMPT}.
+ at findex CONFIGURE_APPLICATION_NEEDS_WATCHDOG_DRIVER
 
- at findex CONFIGURE_INIT_TASK_ARGUMENTS
- at item @code{CONFIGURE_INIT_TASK_ARGUMENTS}
-is the task argument
-of the single initialization task defined by the
-Classic API Initialization Tasks Table.  By default
-the value is 0.
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_APPLICATION_NEEDS_WATCHDOG_DRIVER}
 
- at end itemize
+ at item DATA TYPE:
+Boolean feature macro.
 
+ at item RANGE:
+Defined or undefined.
 
- at subsection POSIX API Configuration
+ at item DEFAULT VALUE:
+By default, this is not defined.
 
-The parameters in this section are used to configure resources
-for the RTEMS POSIX API.  They are only relevant if the POSIX API
-is enabled at configure time using the @code{--enable-posix} option.
+ at end table
 
- at itemize @bullet
- at findex CONFIGURE_MAXIMUM_POSIX_THREADS
- at item @code{CONFIGURE_MAXIMUM_POSIX_THREADS} is the maximum number of
-POSIX API threads that can be concurrently active.
-The default is 0.
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_APPLICATION_NEEDS_WATCHDOG_DRIVER}
+is defined if the application wishes to include the Watchdog Driver.
 
- at findex CONFIGURE_MAXIMUM_POSIX_MUTEXES
- at item @code{CONFIGURE_MAXIMUM_POSIX_MUTEXES} is the maximum number of
-POSIX API mutexes that can be concurrently active.
-The default is 0.
+ at subheading NOTES:
+Most BSPs do not include support for a watchdog device driver. This is
+because many boards do not include the required hardware.
 
- at findex CONFIGURE_MAXIMUM_POSIX_CONDITION_VARIABLES
- at item @code{CONFIGURE_MAXIMUM_POSIX_CONDITION_VARIABLES} is the maximum number of
-POSIX API condition variables that can be concurrently active.
-The default is 0.
+If this is defined and the BSP does not have this device driver, then
+the user will get a link time error for an undefined symbol.
 
- at findex CONFIGURE_MAXIMUM_POSIX_KEYS
- at item @code{CONFIGURE_MAXIMUM_POSIX_KEYS} is the maximum number of
-POSIX API keys that can be concurrently active.
-The default is 0.
+ at c
+ at c === CONFIGURE_APPLICATION_NEEDS_FRAME_BUFFER_DRIVER ===
+ at c
+ at subsection Enable the Graphics Frame Buffer Device Driver
 
- at findex CONFIGURE_MAXIMUM_POSIX_TIMERS
- at item @code{CONFIGURE_MAXIMUM_POSIX_TIMERS} is the maximum number of
-POSIX API timers that can be concurrently active.
-The default is 0.
+ at findex CONFIGURE_APPLICATION_NEEDS_FRAME_BUFFER_DRIVER
 
- at findex CONFIGURE_MAXIMUM_POSIX_QUEUED_SIGNALS
- at item @code{CONFIGURE_MAXIMUM_POSIX_QUEUED_SIGNALS} is the maximum number of
-POSIX API queued signals that can be concurrently active.
-The default is 0.
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_APPLICATION_NEEDS_FRAME_BUFFER_DRIVER}
 
- at findex CONFIGURE_MAXIMUM_POSIX_MESSAGE_QUEUES
- at item @code{CONFIGURE_MAXIMUM_POSIX_MESSAGE_QUEUES} is the maximum number of
-POSIX API message queues that can be concurrently active.
-The default is 0.
+ at item DATA TYPE:
+Boolean feature macro.
 
- at findex CONFIGURE_MAXIMUM_POSIX_MESSAGE_QUEUE_DESCRIPTORS
- at item @code{CONFIGURE_MAXIMUM_POSIX_MESSAGE_QUEUE_DESCRIPTORS}
-is the maximum number of POSIX API message
-queue descriptors that can be concurrently
-active. @code{CONFIGURE_MAXIMUM_POSIX_MESSAGE_QUEUE_DESCRIPTORS}
-should be greater than or equal to
- at code{CONFIGURE_MAXIMUM_POSIX_MESSAGE_QUEUES}. The default is 0.
+ at item RANGE:
+Defined or undefined.
 
- at findex CONFIGURE_MAXIMUM_POSIX_SEMAPHORES
- at item @code{CONFIGURE_MAXIMUM_POSIX_SEMAPHORES} is the maximum number of
-POSIX API semaphores that can be concurrently active.
-The default is 0.
+ at item DEFAULT VALUE:
+By default, this is not defined.
 
- at findex CONFIGURE_MAXIMUM_POSIX_BARRIERS
- at item @code{CONFIGURE_MAXIMUM_POSIX_BARRIERS} is the maximum number of
-POSIX API barriers that can be concurrently active.
-The default is 0.
+ at end table
 
- at findex CONFIGURE_MAXIMUM_POSIX_SPINLOCKS
- at item @code{CONFIGURE_MAXIMUM_POSIX_SPINLOCKS} is the maximum number of
-POSIX API spinlocks that can be concurrently active.
-The default is 0.
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_APPLICATION_NEEDS_FRAME_BUFFER_DRIVER} is defined
+if the application wishes to include the BSP's Frame Buffer Device Driver.
 
- at findex CONFIGURE_MAXIMUM_POSIX_RWLOCKS
- at item @code{CONFIGURE_MAXIMUM_POSIX_RWLOCKS} is the maximum number of
-POSIX API read-write locks that can be concurrently active.
-The default is 0.
+ at subheading NOTES:
+Most BSPs do not include support for a Frame Buffer Device Driver. This is
+because many boards do not include the required hardware.
 
- at end itemize
+If this is defined and the BSP does not have this device driver, then
+the user will get a link time error for an undefined symbol.
 
- at subsection POSIX Initialization Threads Table Configuration
+ at c
+ at c === CONFIGURE_APPLICATION_NEEDS_STUB_DRIVER ===
+ at c
+ at subsection Enable Stub Device Driver
 
-The @code{rtems/confdefs.h} configuration system can automatically
-generate a POSIX Initialization Threads Table named 
- at code{POSIX_Initialization_threads} with a single entry.  The following
-parameters control the generation of that table.
+ at findex CONFIGURE_APPLICATION_NEEDS_STUB_DRIVER
 
- at itemize @bullet
- at findex CONFIGURE_POSIX_INIT_THREAD_TABLE
- at item @code{CONFIGURE_POSIX_INIT_THREAD_TABLE}
-is defined
-if the user wishes to use a POSIX API Initialization
-Threads Table.  The application may choose to use the initialization
-tasks or threads table from another API.  By default, this
-field is not defined as the user MUST select their own
-API for initialization tasks.
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_APPLICATION_NEEDS_STUB_DRIVER}
 
- at findex CONFIGURE_POSIX_HAS_OWN_INIT_THREAD_TABLE
- at item @code{CONFIGURE_POSIX_HAS_OWN_INIT_THREAD_TABLE}
-is defined if the user wishes to define their own POSIX API Initialization
-Threads Table.  This table should be named @code{POSIX_Initialization_threads}.
+ at item DATA TYPE:
+Boolean feature macro.
+
+ at item RANGE:
+Defined or undefined.
+
+ at item DEFAULT VALUE:
 By default, this is not defined.
 
- at findex CONFIGURE_POSIX_INIT_THREAD_ENTRY_POINT
- at item @code{CONFIGURE_POSIX_INIT_THREAD_ENTRY_POINT}
-is the entry point (a.k.a. function name)
-of the single initialization thread defined by the
-POSIX API Initialization Threads Table.  By default
-the value is @code{POSIX_Init}.
+ at end table
 
- at findex CONFIGURE_POSIX_INIT_THREAD_STACK_SIZE
- at item @code{CONFIGURE_POSIX_INIT_THREAD_STACK_SIZE}
-is the stack size of the single initialization thread defined by the
-POSIX API Initialization Threads Table.  By default
-value is twice the configured minimum stack size.
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_APPLICATION_NEEDS_STUB_DRIVER} is defined if the
+application wishes to include the Stub Device Driver.
 
- at end itemize
+ at subheading NOTES:
+This device driver simply provides entry points that return successful
+and is primarily a test fixture. It is supported by all BSPs.
 
- at subsection Ada Tasks
+ at c
+ at c === CONFIGURE_APPLICATION_PREREQUISITE_DRIVERS ===
+ at c
+ at subsection Specify Application Prerequisite Device Drivers
 
-This section defines the system configuration parameters supported
-by @code{rtems/confdefs.h} related to configuring RTEMS to support
-a task using Ada tasking with GNAT.
+ at findex CONFIGURE_APPLICATION_PREREQUISITE_DRIVERS
 
- at itemize @bullet
- at findex CONFIGURE_GNAT_RTEMS
- at item @code{CONFIGURE_GNAT_RTEMS} is defined to inform
-RTEMS that the GNAT Ada run-time is to be used by the 
-application.  This configuration parameter is critical
-as it makes @code{rtems/confdefs.h} configure the resources
-(mutexes and keys) used implicitly by the GNAT run-time.
-By default, this parameter is not defined.
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_APPLICATION_PREREQUISITE_DRIVERS}
 
- at findex CONFIGURE_MAXIMUM_ADA_TASKS
- at item @code{CONFIGURE_MAXIMUM_ADA_TASKS} is the 
-number of Ada tasks that can be concurrently active
-in the system.  By default, when @code{CONFIGURE_GNAT_RTEMS}
-is defined, this is set to 20.
+ at item DATA TYPE:
+device driver entry structures
 
- at findex CONFIGURE_MAXIMUM_FAKE_ADA_TASKS
- at item @code{CONFIGURE_MAXIMUM_FAKE_ADA_TASKS} is
-the number of "fake" Ada tasks that can be concurrently
-active in the system.  A "fake" Ada task is a non-Ada
-task that makes calls back into Ada code and thus
-implicitly uses the Ada run-time.
+ at item RANGE:
+Undefined or set of device driver entry structures
 
- at end itemize
+ at item DEFAULT VALUE:
+By default,this is not defined.
 
- at section Configuration Data Structures
+ at end table
 
-It is recommended that applications be configured using
- at code{rtems/confdefs.h} as it is simpler and insulates applications from
-changes in the underlying data structures.  However, it is sometimes
-important to understand the data structures that are automatically filled
-in by the configuration parameters.  This section describes the primary
-configuration data structures.
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_APPLICATION_PREREQUISITE_DRIVERS} is defined if the
+application has device drivers it needs to include in the Device Driver
+Table.  This should be defined to the set of device driver entries that
+will be placed in the table at the @b{FRONT} of the Device Driver Table
+and initialized before any other drivers @b{EXCEPT} any BSP prerequisite
+drivers.
 
- at subsection Configuration Table
+ at subheading NOTES:
+In some cases, it is used by System On Chip BSPs to support peripheral
+buses beyond those normally found on the System On Chip. For example,
+this is used by one RTEMS system which has implemented a SPARC/ERC32
+based board with VMEBus. The VMEBus Controller initialization is performed
+by a device driver configured via this configuration parameter.
 
- at cindex Configuration Table
- at cindex RTEMS Configuration Table
+ at c XXX Add example
 
-The RTEMS Configuration Table is used to tailor an
-application for its specific needs.  For example, the user can
-configure the number of device drivers or which APIs may be used.
-THe address of the user-defined Configuration Table is passed as an
-argument to the @code{rtems_initialize_executive}
-directive, which MUST be the first RTEMS directive called.  
-The RTEMS Configuration Table is defined in the following C structure:
+ at c
+ at c === CONFIGURE_APPLICATION_EXTRA_DRIVERS ===
+ at c
+ at subsection Specify Extra Application Device Drivers
 
- at findex rtems_configuration_table
- at example
- at group
-typedef struct @{
-  void                           *work_space_start;
-  uintptr_t                       work_space_size;
-  uint32_t                        maximum_extensions;
-  uint32_t                        microseconds_per_tick;
-  uint32_t                        ticks_per_timeslice;
-  uint32_t                        scheduler_policy;
-  void                          (*idle_task)( void );
-  uint32_t                        idle_task_stack_size;
-  uint32_t                        interrupt_stack_size;
-  void *                        (*stack_allocate_hook)( size_t );
-  void                          (*stack_free_hook)( void * );
-  bool                            do_zero_of_workspace;
-  uint32_t                        maximum_drivers;
-  uint32_t                        number_of_device_drivers;
-  rtems_driver_address_table     *Device_driver_table;
-  uint32_t                        number_of_initial_extensions;
-  rtems_extensions_table         *User_extension_table;
-#if defined(RTEMS_MULTIPROCESSING)
-  rtems_multiprocessing_table    *User_multiprocessing_table;
-#endif
-  rtems_api_configuration_table  *RTEMS_api_configuration;
-  posix_api_configuration_table  *POSIX_api_configuration;
-@} rtems_configuration_table;
- at end group
- at end example
+ at findex CONFIGURE_APPLICATION_EXTRA_DRIVERS
 
 @table @b
- at item work_space_start
-is the address of the RTEMS RAM Workspace.  
-This area contains items such as the
-various object control blocks (TCBs, QCBs, ...) and task stacks.
-If the address is not aligned on a four-word boundary, then
-RTEMS will invoke the fatal error handler during
- at code{rtems_initialize_executive}.
-When using the @code{rtems/confdefs.h} mechanism for configuring
-an RTEMS application, the value for this field corresponds
-to the setting of the macro @code{CONFIGURE_EXECUTIVE_RAM_WORK_AREA}
-which defaults to @code{NULL}.  Normally, this field should be 
-configured as @code{NULL} as BSPs will assign memory for the
-RTEMS RAM Workspace as part of system initialization.
-
- at item work_space_size
-is the calculated size of the
-RTEMS RAM Workspace.  The section Sizing the RTEMS RAM Workspace
-details how to arrive at this number.
-When using the @code{rtems/confdefs.h} mechanism for configuring
-an RTEMS application, the value for this field corresponds
-to the setting of the macro @code{CONFIGURE_EXECUTIVE_RAM_SIZE}
-and is calculated based on the other system configuration settings.
-
- at item microseconds_per_tick
-is number of microseconds per clock tick.
-When using the @code{rtems/confdefs.h} mechanism for configuring
-an RTEMS application, the value for this field corresponds
-to the setting of the macro @code{CONFIGURE_MICROSECONDS_PER_TICK}.
-If not defined by the application, then the
- at code{CONFIGURE_MICROSECONDS_PER_TICK} macro defaults to 10000 
-(10 milliseconds).
-
- at item ticks_per_timeslice
-is the number of clock ticks for a timeslice.
-When using the @code{rtems/confdefs.h} mechanism for configuring
-an RTEMS application, the value for this field corresponds
-to the setting of the macro @code{CONFIGURE_TICKS_PER_TIMESLICE}.
-
- at item scheduler_policy
-is the algorithm to use for task scheduling.
-When using the @code{rtems/confdefs.h} mechanism for configuring
-an RTEMS application, the value for this field corresponds
-to the setting of the macro @code{CONFIGURE_SCHEDULER_POLICY}.
-
- at item idle_task
-is the address of the optional user
-provided routine which is used as the system's IDLE task.  If
-this field is not NULL, then the RTEMS default IDLE task is not
-used.  This field may be NULL to indicate that the default IDLE
-is to be used.  When using the @code{rtems/confdefs.h} mechanism
-for configuring an RTEMS application, the value for this field
-corresponds to the setting of the macro @code{CONFIGURE_IDLE_TASK_BODY}.
-
- at item idle_task_stack_size
-is the size of the RTEMS idle task stack in bytes.  If this number is less
-than the configured minimum stack size, then the idle task's stack will
-be set to the minimum.  When using the @code{rtems/confdefs.h} mechanism
-for configuring an RTEMS application, the value for this field corresponds
-to the setting of the macro @code{CONFIGURE_IDLE_TASK_STACK_SIZE}.
-
- at item interrupt_stack_size
-is the size of the RTEMS interrupt stack in bytes.  If this number is less
-than configured minimum stack size, then the interrupt stack will be set
-to the minimum.  When using the @code{rtems/confdefs.h} mechanism for
-configuring an RTEMS application, the value for this field corresponds
-to the setting of the macro @code{CONFIGURE_INTERRUPT_STACK_SIZE}.
-
- at item stack_allocate_hook
-may point to a user provided routine to allocate task stacks.
-The default is to allocate task stacks from the RTEMS Workspace.
-When using the @code{rtems/confdefs.h} mechanism
-for configuring an RTEMS application, the value for this field
-corresponds to the setting of the macro
- at code{CONFIGURE_TASK_STACK_ALLOCATOR}.
-
- at item stack_free_hook
-may point to a user provided routine to free task stacks.
-The default is to allocate task stacks from the RTEMS Workspace.
-When using the @code{rtems/confdefs.h} mechanism
-for configuring an RTEMS application, the value for this field
-corresponds to the setting of the macro
- at code{CONFIGURE_TASK_STACK_DEALLOCATOR}.
-
- at item do_zero_of_workspace
-indicates whether RTEMS should zero the RTEMS Workspace and
-C Program Heap as part of its initialization.  If set to
-TRUE, the Workspace is zeroed.  Otherwise, it is not.
-When using the @code{rtems/confdefs.h} mechanism
-for configuring an RTEMS application, the value for this field
-corresponds to the setting of the macro
- at code{CONFIGURE_ZERO_WORKSPACE_AUTOMATICALLY}.
-
- at item maximum_drivers
-is the maximum number of device drivers that can be registered.
-When using the @code{rtems/confdefs.h} mechanism for configuring
-an RTEMS application, the value for this field corresponds
-to the setting of the macro @code{CONFIGURE_MAXIMUM_DRIVERS}.
-
- at item number_of_device_drivers
-is the number of device drivers for the system.  There should be
-the same number of entries in the Device Driver Table.  If this field
-is zero, then the @code{User_driver_address_table} entry should be NULL.
-When using the @code{rtems/confdefs.h} mechanism for configuring
-an RTEMS application, the value for this field is calculated
-automatically based on the number of entries in the 
-Device Driver Table.  This calculation is based on the assumption
-that the Device Driver Table is named @code{Device_drivers}
-and defined in C.  This table may be generated automatically
-for simple applications using only the device drivers that correspond
-to the following macros:
-
- at itemize @bullet
+ at item CONSTANT:
+ at code{CONFIGURE_APPLICATION_EXTRA_DRIVERS}
 
- at item @code{CONFIGURE_APPLICATION_NEEDS_CONSOLE_DRIVER}
- at item @code{CONFIGURE_APPLICATION_NEEDS_CLOCK_DRIVER}
- at item @code{CONFIGURE_APPLICATION_NEEDS_TIMER_DRIVER}
- at item @code{CONFIGURE_APPLICATION_NEEDS_RTC_DRIVER}
- at item @code{CONFIGURE_APPLICATION_NEEDS_STUB_DRIVER}
+ at item DATA TYPE:
+device driver entry structures
 
- at end itemize
+ at item RANGE:
+Undefined or set of device driver entry structures
 
-Note that network device drivers are not configured in the
-Device Driver Table.
-
- at item Device_driver_table
-is the address of the Device Driver Table.  This table contains the entry
-points for each device driver.  If the number_of_device_drivers field is zero,
-then this entry should be NULL. The format of this table will be
-discussed below.
-When using the @code{rtems/confdefs.h} mechanism for configuring
-an RTEMS application, the Device Driver Table is assumed to be
-named @code{Device_drivers} and defined in C.  If the application is providing
-its own Device Driver Table, then the macro
- at code{CONFIGURE_HAS_OWN_DEVICE_DRIVER_TABLE} must be defined to indicate
-this and prevent @code{rtems/confdefs.h} from generating the table.
-
- at item number_of_initial_extensions
-is the number of initial user extensions.  There should be
-the same number of entries as in the User_extension_table.  If this field
-is zero, then the User_driver_address_table entry should be NULL.
-When using the @code{rtems/confdefs.h} mechanism for configuring
-an RTEMS application, the value for this field corresponds
-to the setting of the macro @code{CONFIGURE_NUMBER_OF_INITIAL_EXTENSIONS}
-which is set automatically by @code{rtems/confdefs.h} based on the size
-of the User Extensions Table.
-
- at item User_extension_table
-is the address of the User
-Extension Table.  This table contains the entry points for the
-static set of optional user extensions.  If no user extensions
-are configured, then this entry should be NULL.  The format of
-this table will be discussed below.
-When using the @code{rtems/confdefs.h} mechanism for configuring
-an RTEMS application, the User Extensions Table is named
- at code{Configuration_Initial_Extensions} and defined in
-confdefs.h.  It is initialized based on the following
-macros:
+ at item DEFAULT VALUE:
+By default,this is not defined.
 
- at itemize @bullet
+ at end table
 
- at item @code{CONFIGURE_INITIAL_EXTENSIONS}
- at item @code{STACK_CHECKER_EXTENSION}
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_APPLICATION_EXTRA_DRIVERS} is defined if the
+application has device drivers it needs to include in the Device Driver
+Table.  This should be defined to the set of device driver entries that
+will be placed in the table at the @b{END} of the Device Driver Table.
 
- at end itemize
+ at subheading NOTES:
+None.
 
-The application may configure one or more initial user extension
-sets by setting the @code{CONFIGURE_INITIAL_EXTENSIONS} macro.  By
-defining the @code{STACK_CHECKER_EXTENSION} macro, the task stack bounds
-checking user extension set is automatically included in the
-application.
+ at c
+ at c === CONFIGURE_APPLICATION_NEEDS_NULL_DRIVER ===
+ at c
+ at subsection Enable /dev/null Device Driver
 
- at item User_multiprocessing_table
-is the address of the Multiprocessor Configuration Table.  This
-table contains information needed by RTEMS only when used in a multiprocessor
-configuration.  This field must be NULL when RTEMS is used in a
-single processor configuration.
-When using the @code{rtems/confdefs.h} mechanism for configuring
-an RTEMS application, the Multiprocessor Configuration Table
-is automatically generated when the @code{CONFIGURE_MP_APPLICATION}
-is defined.  If @code{CONFIGURE_MP_APPLICATION} is not defined, the this
-entry is set to NULL.  The generated table has the name
- at code{Multiprocessing_configuration}.
-
- at item RTEMS_api_configuration
-is the address of the RTEMS API Configuration Table.  This table
-contains information needed by the RTEMS API.  This field should be
-NULL if the RTEMS API is not used.  [NOTE: Currently the RTEMS API
-is required to support support components such as BSPs and libraries 
-which use this API.]  This table is built automatically and this
-entry filled in, if using the @code{rtems/confdefs.h} application
-configuration mechanism.  The generated table has the name
- at code{Configuration_RTEMS_API}.
-
- at item POSIX_api_configuration
-is the address of the POSIX API Configuration Table.  This table
-contains information needed by the POSIX API.  This field should be
-NULL if the POSIX API is not used.  This table is built automatically
-and this entry filled in, if using the @code{rtems/confdefs.h} application
-configuration mechanism.  The @code{rtems/confdefs.h} application 
-mechanism will fill this field in with the address of the
- at code{Configuration_POSIX_API} table of POSIX API is configured
-and NULL if the POSIX API is not configured.
-
- at end table
-
- at subsection RTEMS API Configuration Table
-
- at cindex RTEMS API Configuration Table
-
-The RTEMS API Configuration Table is used to configure the 
-managers which constitute the RTEMS API for a particular application.  
-For example, the user can configure the maximum number of tasks for 
-this application. The RTEMS API Configuration Table is defined in 
-the following C structure:
-
- at findex rtems_api_configuration_table
- at example
- at group
-typedef struct @{
-  uint32_t  maximum_tasks;
-  uint32_t  maximum_timers;
-  uint32_t  maximum_semaphores;
-  uint32_t  maximum_message_queues;
-  uint32_t  maximum_partitions;
-  uint32_t  maximum_regions;
-  uint32_t  maximum_ports;
-  uint32_t  maximum_periods;
-  uint32_t  maximum_barriers;
-  uint32_t  number_of_initialization_tasks;
-  rtems_initialization_tasks_table *User_initialization_tasks_table;
-@} rtems_api_configuration_table;
- at end group
- at end example
+ at findex CONFIGURE_APPLICATION_NEEDS_NULL_DRIVER
+ at cindex /dev/null
 
 @table @b
- at item maximum_tasks
-is the maximum number of tasks that
-can be concurrently active (created) in the system including
-initialization tasks.
-When using the @code{rtems/confdefs.h} mechanism for configuring
-an RTEMS application, the value for this field corresponds
-to the setting of the macro @code{CONFIGURE_MAXIMUM_TASKS}.
-If not defined by the application, then the @code{CONFIGURE_MAXIMUM_TASKS}
-macro defaults to 0.
-
- at item maximum_timers
-is the maximum number of timers
-that can be concurrently active in the system.
-When using the @code{rtems/confdefs.h} mechanism for configuring
-an RTEMS application, the value for this field corresponds
-to the setting of the macro @code{CONFIGURE_MAXIMUM_TIMERS}.
-If not defined by the application, then the @code{CONFIGURE_MAXIMUM_TIMERS}
-macro defaults to 0.
-
- at item maximum_semaphores
-is the maximum number of
-semaphores that can be concurrently active in the system.
-When using the @code{rtems/confdefs.h} mechanism for configuring
-an RTEMS application, the value for this field corresponds
-to the setting of the macro @code{CONFIGURE_MAXIMUM_SEMAPHORES}.
-If not defined by the application, then the @code{CONFIGURE_MAXIMUM_SEMAPHORES}
-macro defaults to 0.
-
- at item maximum_message_queues
-is the maximum number of
-message queues that can be concurrently active in the system.
-When using the @code{rtems/confdefs.h} mechanism for configuring
-an RTEMS application, the value for this field corresponds
-to the setting of the macro @code{CONFIGURE_MAXIMUM_MESSAGE_QUEUES}.
-If not defined by the application, then the
- at code{CONFIGURE_MAXIMUM_MESSAGE_QUEUES} macro defaults to 0.
-
- at item maximum_partitions
-is the maximum number of
-partitions that can be concurrently active in the system.
-When using the @code{rtems/confdefs.h} mechanism for configuring
-an RTEMS application, the value for this field corresponds
-to the setting of the macro @code{CONFIGURE_MAXIMUM_PARTITIONS}.
-If not defined by the application, then the @code{CONFIGURE_MAXIMUM_PARTITIONS}
-macro defaults to 0.
-
- at item maximum_regions
-is the maximum number of regions
-that can be concurrently active in the system.
-When using the @code{rtems/confdefs.h} mechanism for configuring
-an RTEMS application, the value for this field corresponds
-to the setting of the macro @code{CONFIGURE_MAXIMUM_REGIONS}.
-If not defined by the application, then the @code{CONFIGURE_MAXIMUM_REGIONS}
-macro defaults to 0.
-
- at item maximum_ports
-is the maximum number of ports into
-dual-port memory areas that can be concurrently active in the
-system.
-When using the @code{rtems/confdefs.h} mechanism for configuring
-an RTEMS application, the value for this field corresponds
-to the setting of the macro @code{CONFIGURE_MAXIMUM_PORTS}.
-If not defined by the application, then the @code{CONFIGURE_MAXIMUM_PORTS}
-macro defaults to 0.
-
- at item number_of_initialization_tasks
-is the number of initialization tasks configured.  At least one
-RTEMS initialization task or POSIX initializatin must be configured
-in order for the user's application to begin executing.
-When using the @code{rtems/confdefs.h} mechanism for configuring
-an RTEMS application, the user must define the
- at code{CONFIGURE_RTEMS_INIT_TASKS_TABLE} to indicate that there
-is one or more RTEMS initialization task.  If the application
-only has one RTEMS initialization task, then the automatically
-generated Initialization Task Table will be sufficient.  The following
-macros correspond to the single initialization task:
-  
- at itemize @bullet
+ at item CONSTANT:
+ at code{CONFIGURE_APPLICATION_NEEDS_NULL_DRIVER}
 
- at item @code{CONFIGURE_INIT_TASK_NAME} - is the name of the task.  
-If this macro is not defined by the application, then this defaults
-to the task name of @code{"UI1 "} for User Initialization Task 1.
+ at item DATA TYPE:
+Boolean feature macro.
 
- at item @code{CONFIGURE_INIT_TASK_STACK_SIZE} - is the stack size
-of the single initialization task.  If this macro is not defined
-by the application, then this defaults to configured minimum
-stack size.
+ at item RANGE:
+Defined or undefined.
 
- at item @code{CONFIGURE_INIT_TASK_PRIORITY} - is the initial priority
-of the single initialization task.  If this macro is not defined
-by the application, then this defaults to 1.
+ at item DEFAULT VALUE:
+By default,this is not defined.
 
- at item @code{CONFIGURE_INIT_TASK_ATTRIBUTES} - is the attributes
-of the single initialization task.  If this macro is not defined
-by the application, then this defaults to @code{RTEMS_DEFAULT_ATTRIBUTES}.
+ at end table
 
- at item @code{CONFIGURE_INIT_TASK_ENTRY_POINT} - is the entry point
-of the single initialization task.  If this macro is not defined
-by the application, then this defaults to the C language routine
- at code{Init}.
+ at subheading DESCRIPTION:
+This configuration variable is specified to enable @i{/dev/null}
+device driver.
 
- at item @code{CONFIGURE_INIT_TASK_INITIAL_MODES} - is the initial execution
-modes of the single initialization task.  If this macro is not defined
-by the application, then this defaults to @code{RTEMS_NO_PREEMPT}.
+ at subheading NOTES:
+This device driver is supported by all BSPs.
 
- at item @code{CONFIGURE_INIT_TASK_ARGUMENTS} - is the argument passed to the 
-of the single initialization task.  If this macro is not defined
-by the application, then this defaults to 0.
+ at c
+ at c === CONFIGURE_APPLICATION_NEEDS_ZERO_DRIVER ===
+ at c
+ at subsection Enable /dev/zero Device Driver
 
+ at findex CONFIGURE_APPLICATION_NEEDS_ZERO_DRIVER
+ at cindex /dev/zero
 
- at end itemize
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_APPLICATION_NEEDS_ZERO_DRIVER}
 
+ at item DATA TYPE:
+Boolean feature macro.
 
-has the option to have 
- value for this field corresponds
-to the setting of the macro @code{}.
+ at item RANGE:
+Defined or undefined.
 
- at item User_initialization_tasks_table
-is the address of the Initialization Task Table. This table contains the
-information needed to create and start each of the
-initialization tasks.  The format of this table will be discussed below.
-When using the @code{rtems/confdefs.h} mechanism for configuring
-an RTEMS application, the value for this field corresponds
-to the setting of the macro @code{CONFIGURE_EXECUTIVE_RAM_WORK_AREA}.
+ at item DEFAULT VALUE:
+By default,this is not defined.
 
 @end table
 
- at subsection POSIX API Configuration Table
+ at subheading DESCRIPTION:
+This configuration variable is specified to enable @i{/dev/zero}
+device driver.
 
- at cindex POSIX API Configuration Table
+ at subheading NOTES:
+This device driver is supported by all BSPs.
 
-The POSIX API Configuration Table is used to configure the
-managers which constitute the POSIX API for a particular application.
-For example, the user can configure the maximum number of threads for
-this application. The POSIX API Configuration Table is defined in
-the following C structure:
- 
- at findex posix_initialization_threads_table
- at findex posix_api_configuration_table
- at example
- at group
-typedef struct @{
-  void       *(*thread_entry)(void *);
-@} posix_initialization_threads_table;
- 
-typedef struct @{
-  int                                 maximum_threads;
-  int                                 maximum_mutexes;
-  int                                 maximum_condition_variables;
-  int                                 maximum_keys;
-  int                                 maximum_timers;
-  int                                 maximum_queued_signals;
-  int                                 maximum_message_queues;
-  int                                 maximum_message_queue_descriptors;
-  int                                 maximum_semaphores;
-  int                                 maximum_barriers;
-  int                                 maximum_rwlocks;
-  int                                 maximum_spinlocks;
-  int                                 number_of_initialization_threads;
-  posix_initialization_threads_table *User_initialization_tasks_table;
-@} posix_api_configuration_table;
- at end group
- at end example
- 
- at table @b
- at item maximum_threads
-is the maximum number of threads that
-can be concurrently active (created) in the system including
-initialization threads.
-When using the @code{rtems/confdefs.h} mechanism for configuring
-an RTEMS application, the value for this field corresponds
-to the setting of the macro @code{CONFIGURE_MAXIMUM_POSIX_THREADS}.
-If not defined by the application, then the
- at code{CONFIGURE_MAXIMUM_POSIX_THREADS} macro defaults to 0.
-
- at item maximum_mutexes
-is the maximum number of mutexes that can be concurrently 
-active in the system.
-When using the @code{rtems/confdefs.h} mechanism for configuring
-an RTEMS application, the value for this field corresponds
-to the setting of the macro @code{CONFIGURE_MAXIMUM_POSIX_MUTEXES}.
-If not defined by the application, then the
- at code{CONFIGURE_MAXIMUM_POSIX_MUTEXES} macro defaults to 0.
-
- at item maximum_condition_variables
-is the maximum number of condition variables that can be 
-concurrently active in the system.
-When using the @code{rtems/confdefs.h} mechanism for configuring
-an RTEMS application, the value for this field corresponds
-to the setting of the macro @code{CONFIGURE_MAXIMUM_POSIX_CONDITION_VARIABLES}.
-If not defined by the application, then the
- at code{CONFIGURE_MAXIMUM_POSIX_CONDITION_VARIABLES} macro defaults to 0.
-
- at item maximum_keys
-is the maximum number of keys that can be concurrently active in the system.
-When using the @code{rtems/confdefs.h} mechanism for configuring
-an RTEMS application, the value for this field corresponds
-to the setting of the macro @code{CONFIGURE_MAXIMUM_POSIX_KEYS}.
-If not defined by the application, then the
- at code{CONFIGURE_MAXIMUM_POSIX_KEYS} macro defaults to 0.
-
- at item maximum_timers
-is the maximum number of POSIX timers that can be concurrently active
-in the system.
-When using the @code{rtems/confdefs.h} mechanism for configuring
-an RTEMS application, the value for this field corresponds
-to the setting of the macro @code{CONFIGURE_MAXIMUM_POSIX_TIMERS}.
-If not defined by the application, then the
- at code{CONFIGURE_MAXIMUM_POSIX_TIMERS} macro defaults to 0.
-
- at item maximum_queued_signals
-is the maximum number of queued signals that can be concurrently 
-pending in the system.
-When using the @code{rtems/confdefs.h} mechanism for configuring
-an RTEMS application, the value for this field corresponds
-to the setting of the macro @code{CONFIGURE_MAXIMUM_POSIX_QUEUED_SIGNALS}.
-If not defined by the application, then the
- at code{CONFIGURE_MAXIMUM_POSIX_QUEUED_SIGNALS} macro defaults to 0.
-
- at item maximum_message_queues
-is the maximum number of POSIX message queues that can be concurrently
-active in the system.  When using the @code{rtems/confdefs.h}
-mechanism for configuring an RTEMS application, the
-value for this field corresponds to the setting of the macro
- at code{CONFIGURE_MAXIMUM_POSIX_MESSAGE_QUEUES}.  If not defined by the
-application, then the @code{CONFIGURE_MAXIMUM_POSIX_MESSAGE_QUEUES}
-macro defaults to 0.
-
- at item maximum_message_queue_descriptors
-is the maximum number of POSIX message queue descriptors
-that can be concurrently active in the system.  When using the
- at code{rtems/confdefs.h} mechanism for configuring an RTEMS application,
-the value for this field corresponds to the setting of the macro
- at code{CONFIGURE_MAXIMUM_POSIX_MESSAGE_QUEUE_DESCRIPTORS}.
-If not defined by the application, then the
- at code{CONFIGURE_MAXIMUM_POSIX_MESSAGE_QUEUE_DESCRIPTORS} macro defaults
-to the value of @code{CONFIGURE_MAXIMUM_POSIX_MESSAGE_QUEUES}
-
- at item maximum_semaphores
-is the maximum number of POSIX semaphore that can be concurrently
-active in the system.  When using the @code{rtems/confdefs.h}
-mechanism for configuring an RTEMS application, the
-value for this field corresponds to the setting of the macro
- at code{CONFIGURE_MAXIMUM_POSIX_SEMAPHORES}.  If not defined by the
-application, then the @code{CONFIGURE_MAXIMUM_POSIX_SEMAPHORES}
-macro defaults to 0.
-
- at item maximum_barriers
-is the maximum number of POSIX barriers that can be concurrently
-active in the system.  When using the @code{rtems/confdefs.h}
-mechanism for configuring an RTEMS application, the
-value for this field corresponds to the setting of the macro
- at code{CONFIGURE_MAXIMUM_POSIX_BARRIERS}.  If not defined by the
-application, then the @code{CONFIGURE_MAXIMUM_POSIX_BARRIERS}
-macro defaults to 0.
-
- at item maximum_rwlocks
-is the maximum number of POSIX rwlocks that can be concurrently
-active in the system.  When using the @code{rtems/confdefs.h}
-mechanism for configuring an RTEMS application, the
-value for this field corresponds to the setting of the macro
- at code{CONFIGURE_MAXIMUM_POSIX_SPINLOCKS}.  If not defined by the
-application, then the @code{CONFIGURE_MAXIMUM_POSIX_SPINLOCKS}
-macro defaults to 0.
-
- at item maximum_spinlocks
-is the maximum number of POSIX spinlocks that can be concurrently
-active in the system.  When using the @code{rtems/confdefs.h}
-mechanism for configuring an RTEMS application, the
-value for this field corresponds to the setting of the macro
- at code{CONFIGURE_MAXIMUM_POSIX_MESSAGE_QUEUES}.  If not defined by the
-application, then the @code{CONFIGURE_MAXIMUM_POSIX_MESSAGE_QUEUES}
-macro defaults to 0.
-
- at item number_of_initialization_threads
-is the number of initialization threads configured.  At least one
-initialization threads must be configured.
-When using the @code{rtems/confdefs.h} mechanism for configuring
-an RTEMS application, the user must define the
- at code{CONFIGURE_POSIX_INIT_THREAD_TABLE} to indicate that there
-is one or more POSIX initialization thread.  If the application
-only has one POSIX initialization thread, then the automatically
-generated POSIX Initialization Thread Table will be sufficient.  The following
-macros correspond to the single initialization task:
+ at c
+ at c === Multiprocessing Configuration ===
+ at c
+ at section Multiprocessing Configuration
 
- at itemize @bullet
+This section defines the multiprocessing related system configuration
+parameters supported by @code{<rtems/confdefs.h>}.  They are only used
+if the Multiprocessing Support (distinct from the SMP support) is enabled
+at configure time using the @code{--enable-multiprocessing} option.
 
- at item @code{CONFIGURE_POSIX_INIT_THREAD_ENTRY_POINT} - is the entry
-point of the thread.  If this macro is not defined by the application,
-then this defaults to the C routine @code{POSIX_Init}.
+Additionally, this class of Configuration Constants are only applicable if
+ at code{CONFIGURE_MP_APPLICATION} is defined.
 
- at item @code{CONFIGURE_POSIX_INIT_TASK_STACK_SIZE} - is the stack size
-of the single initialization thread.  If this macro is not defined
-by the application, then this defaults to twice the configured
-minimum stack size.
+ at c
+ at c === CONFIGURE_MP_APPLICATION ===
+ at c
+ at subsection Specify Application Will Use Multiprocessing
 
- at end itemize
- 
- at item User_initialization_threads_table
-is the address of the Initialization Threads Table. This table contains the
-information needed to create and start each of the initialization threads.  
-The format of each entry in this table is defined in the 
- at code{posix_initialization_threads_table} structure.
-When using the @code{rtems/confdefs.h} mechanism for configuring
-an RTEMS application, the value for this field corresponds
-to the address of the @code{POSIX_Initialization_threads} structure.
+ at findex CONFIGURE_MP_APPLICATION
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_MP_APPLICATION}
+
+ at item DATA TYPE:
+Boolean feature macro.
+
+ at item RANGE:
+Defined or undefined.
+
+ at item DEFAULT VALUE:
+This is not defined by default.
 
 @end table
 
- at subsection CPU Dependent Information Table
+ at subheading DESCRIPTION:
+This configuration parameter must be defined to indicate
+that the application intends to be part of a multiprocessing
+configuration. Additional configuration parameters are assumed to be
+provided.
 
- at cindex CPU Dependent Information Table
+ at subheading NOTES:
+This has no impact unless RTEMS was configured and built using the
+ at code{--enable-multiprocessing} option.
 
-The CPU Dependent Information Table is used to
-describe processor dependent information required by RTEMS.
-This table is generally used to supply RTEMS with information
-only known by the Board Support Package.  The contents of this
-table are discussed in the CPU Dependent Information Table
-chapter of the Applications Supplement document for a specific
-target processor.
+ at c
+ at c === CONFIGURE_MP_NODE_NUMBER ===
+ at c
+ at subsection Configure Node Number in Multiprocessor Configuration
 
-The @code{rtems/confdefs.h} mechanism does not support generating this
-table.  It is normally filled in by the Board Support Package.
+ at findex CONFIGURE_MP_NODE_NUMBER
 
- at subsection Initialization Task Table
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_MP_NODE_NUMBER}
 
- at cindex Initialization Tasks Table
+ at item DATA TYPE:
+integer
 
-The Initialization Task Table is used to describe
-each of the user initialization tasks to the Initialization
-Manager.  The table contains one entry for each initialization
-task the user wishes to create and start.  The fields of this
-data structure directly correspond to arguments to the
- at code{@value{DIRPREFIX}task_create} and
- at code{@value{DIRPREFIX}task_start} directives.  The number of entries is
-found in the @code{number_of_initialization_tasks} entry in the
-Configuration Table.  
+ at item RANGE:
+positive integer
 
-The format of each entry in the
-Initialization Task Table is defined in the following C structure:
+ at item DEFAULT VALUE:
+If not defined, it is set to @code{NODE_NUMBER} which is assumed to be
+set by the compilation environment.
 
- at findex rtems_initialization_tasks_table
- at example
-typedef struct @{
-  rtems_name           name;
-  size_t               stack_size;
-  rtems_task_priority  initial_priority;
-  rtems_attribute      attribute_set;
-  rtems_task_entry     entry_point;
-  rtems_mode           mode_set;
-  rtems_task_argument  argument;
-@} rtems_initialization_tasks_table;
- at end example
+ at end table
 
- at table @b
- at item name
-is the name of this initialization task.
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_MP_NODE_NUMBER} is the node number of
+this node in a multiprocessor system.
 
- at item stack_size
-is the size of the stack for this initialization task.
+ at subheading NOTES:
+In the RTEMS Multiprocessing Test Suite, the node number is derived from
+the Makefile variable @code{NODE_NUMBER}. The same code is compiled with
+the @code{NODE_NUMBER} set to different values. The test programs behave
+differently based upon their node number.
 
- at item initial_priority
-is the priority of this initialization task.
 
- at item attribute_set
-is the attribute set used during creation of this initialization task.
+ at c
+ at c === CONFIGURE_MP_MAXIMUM_NODES ===
+ at c
+ at subsection Configure Maximum Node in Multiprocessor Configuration
 
- at item entry_point
-is the address of the entry point of this initialization task.
+ at findex CONFIGURE_MP_MAXIMUM_NODES
 
- at item mode_set
-is the initial execution mode of this initialization task.
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_MP_MAXIMUM_NODES}
 
- at item argument
-is the initial argument for this initialization task.
+ at item DATA TYPE:
+integer
 
- at end table
+ at item RANGE:
+positive
 
-A typical declaration for an Initialization Task Table might appear as follows:
+ at item DEFAULT VALUE:
+The default is two (2).
 
- at example
-rtems_initialization_tasks_table
-Initialization_tasks[2] = @{
-   @{ INIT_1_NAME,
-     1024,
-     1,
-     DEFAULT_ATTRIBUTES,
-     Init_1,
-     DEFAULT_MODES,
-     1
-
-   @},
-   @{ INIT_2_NAME,
-     1024,
-     250,
-     FLOATING_POINT,
-     Init_2,
-     NO_PREEMPT,
-     2
-
-   @}
-@};
- at end example
+ at end table
 
- at subsection Driver Address Table
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_MP_MAXIMUM_NODES} is the maximum number of nodes in a
+multiprocessor system.
 
- at cindex Device Driver Table
+ at subheading NOTES:
+None.
 
-The Device Driver Table is used to inform the I/O Manager of the set of
-entry points for each device driver configured in the system.  The table
-contains one entry for each device driver required by the application.
-The number of entries is defined in the number_of_device_drivers entry
-in the Configuration Table.  This table is copied to the Device Drive
-Table during the IO Manager's initialization giving the entries in this
-table the lower major numbers.  The format of each entry in the Device
-Driver Table is defined in the following C structure:
+ at c
+ at c === CONFIGURE_MP_MAXIMUM_GLOBAL_OBJECTS ===
+ at c
+ at subsection Configure Maximum Global Objects in Multiprocessor Configuration
 
- at findex rtems_driver_address_table
- at example
-typedef struct @{
-  rtems_device_driver_entry initialization_entry;
-  rtems_device_driver_entry open_entry;
-  rtems_device_driver_entry close_entry;
-  rtems_device_driver_entry read_entry;
-  rtems_device_driver_entry write_entry;
-  rtems_device_driver_entry control_entry;
-@} rtems_driver_address_table;
- at end example
+ at findex CONFIGURE_MP_MAXIMUM_GLOBAL_OBJECTS
 
 @table @b
- at item initialization_entry
-is the address of the entry point called by
- at code{rtems_io_initialize}
-to initialize a device driver and its associated devices.
+ at item CONSTANT:
+ at code{CONFIGURE_MP_MAXIMUM_GLOBAL_OBJECTS}
+
+ at item DATA TYPE:
+integer
+
+ at item RANGE:
+positive
+
+ at item DEFAULT VALUE:
+The default is 32.
+
+ at end table
 
- at item open_entry
-is the address of the entry point called by @code{rtems_io_open}.
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_MP_MAXIMUM_GLOBAL_OBJECTS} is the maximum number of
+concurrently active global objects in a multiprocessor system.
 
- at item close_entry
-is the address of the entry point called by @code{rtems_io_close}.
+ at subheading NOTES:
+This value corresponds to the total number of objects which can be
+created with the @code{RTEMS_GLOBAL} attribute.
+
+ at c
+ at c === CONFIGURE_MP_MAXIMUM_PROXIES ===
+ at c
+ at subsection Configure Maximum Proxies in Multiprocessor Configuration
+
+ at findex CONFIGURE_MP_MAXIMUM_PROXIES
+
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_MP_MAXIMUM_PROXIES}
 
- at item read_entry
-is the address of the entry point called by @code{rtems_io_read}.
+ at item DATA TYPE:
+integer
 
- at item write_entry
-is the address of the entry point called by @code{rtems_io_write}.
+ at item RANGE:
+undefined or positive
 
- at item control_entry
-is the address of the entry point called by @code{rtems_io_control}.
+ at item DEFAULT VALUE:
+The default is 32.
 
 @end table
 
-Driver entry points configured as NULL will always
-return a status code of @code{@value{RPREFIX}SUCCESSFUL}.  No user code will be
-executed in this situation.
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_MP_MAXIMUM_PROXIES} is the maximum number of concurrently
+active thread/task proxies on this node in a multiprocessor system.
 
-A typical declaration for a Device Driver Table might appear as follows:
+ at subheading NOTES:
+Since a proxy is used to represent a remote task/thread which is blocking on
+this node. This configuration parameter reflects the maximum number of
+remote tasks/threads which can be blocked on objects on this node.
 
- at example
-rtems_driver_address_table Driver_table[2] = @{
-   @{ tty_initialize, tty_open,  tty_close,  /* major = 0 */
-     tty_read,       tty_write, tty_control
-   @},
-   @{ lp_initialize, lp_open,    lp_close,   /* major = 1 */
-     NULL,          lp_write,   lp_control
-   @}
-@};
- at end example
+ at c XXX - add xref to proxy discussion in MP chapter
 
-More information regarding the construction and
-operation of device drivers is provided in the I/O Manager
-chapter.
+ at c
+ at c === CONFIGURE_MP_MPCI_TABLE_POINTER ===
+ at c
+ at subsection Configure MPCI in Multiprocessor Configuration
 
- at subsection User Extensions Table
+ at findex CONFIGURE_MP_MPCI_TABLE_POINTER
 
- at cindex User Extensions Table
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_MP_MPCI_TABLE_POINTER}
 
-The User Extensions Table is used to inform RTEMS of
-the optional user-supplied static extension set.  This table
-contains one entry for each possible extension.  The entries are
-called at critical times in the life of the system and
-individual tasks.  The application may create dynamic extensions
-in addition to this single static set.  The format of each entry
-in the User Extensions Table is defined in the following C structure:
+ at item DATA TYPE:
+pointer to @code{rtems_mpci_table}
 
- at example
-typedef void           rtems_extension;
-typedef void (*rtems_task_create_extension)(
-   Thread_Control * /* executing */,
-   Thread_Control * /* created */
-);
-typedef void (*rtems_task_delete_extension)(
-   Thread_Control * /* executing */,
-   Thread_Control * /* deleted */
-);
-typedef void (*rtems_task_start_extension)(
-   Thread_Control * /* executing */,
-   Thread_Control * /* started */
-);
-typedef void (*rtems_task_restart_extension)(
-   Thread_Control * /* executing */,
-   Thread_Control * /* restarted */
-);
-typedef void (*rtems_task_switch_extension)(
-   Thread_Control * /* executing */,
-   Thread_Control * /* heir */
-);
-typedef void (*rtems_task_begin_extension)(
-   Thread_Control * /* beginning */
-);
-typedef void (*rtems_task_exitted_extension)(
-   Thread_Control * /* exiting */
-);
-typedef void (*rtems_fatal_extension)(
-   Internal_errors_Source /* the_source */,
-   bool                   /* is_internal */,
-   uint32_t               /* the_error */
-);
-
-typedef struct @{
-  rtems_task_create_extension      thread_create;
-  rtems_task_start_extension       thread_start;
-  rtems_task_restart_extension     thread_restart;
-  rtems_task_delete_extension      thread_delete;
-  rtems_task_switch_extension      thread_switch;
-  rtems_task_begin_extension       thread_begin;
-  rtems_task_exitted_extension     thread_exitted;
-  rtems_fatal_extension            fatal;
-@} rtems_extensions_table;
- at end example
+ at item RANGE:
+undefined or valid pointer
+
+ at item DEFAULT VALUE:
+This is not defined by default.
+
+ at end table
+
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_MP_MPCI_TABLE_POINTER} is the pointer to the
+MPCI Configuration Table.  The default value of this field is
+ at code{&MPCI_table}.
+
+ at subheading NOTES:
+RTEMS provides a Shared Memory MPCI Device Driver which can be used on
+any Multiprocessor System assuming the BSP provides the proper set of
+supporting methods.
+
+ at c
+ at c === CONFIGURE_HAS_OWN_MULTIPROCESSING_TABLE ===
+ at c
+ at subsection Do Not Generate Multiprocessor Configuration Table
+
+ at findex CONFIGURE_HAS_OWN_MULTIPROCESSING_TABLE
 
 @table @b
+ at item CONSTANT:
+ at code{CONFIGURE_HAS_OWN_MULTIPROCESSING_TABLE}
 
- at item thread_create
-is the address of the
-user-supplied subroutine for the TASK_CREATE extension.  If this
-extension for task creation is defined, it is called from the
-task_create directive.  A value of NULL indicates that no
-extension is provided.
+ at item DATA TYPE:
+Boolean feature macro.
 
- at item thread_start
-is the address of the user-supplied
-subroutine for the TASK_START extension.  If this extension for
-task initiation is defined, it is called from the task_start
-directive.  A value of NULL indicates that no extension is
-provided.
+ at item RANGE:
+Defined or undefined.
 
- at item thread_restart
-is the address of the user-supplied
-subroutine for the TASK_RESTART extension.  If this extension
-for task re-initiation is defined, it is called from the
-task_restart directive.  A value of NULL indicates that no
-extension is provided.
-
- at item thread_delete
-is the address of the user-supplied
-subroutine for the TASK_DELETE extension.  If this RTEMS
-extension for task deletion is defined, it is called from the
-task_delete directive.  A value of NULL indicates that no
-extension is provided.
-
- at item thread_switch
-is the address of the user-supplied
-subroutine for the task context switch extension.  This
-subroutine is called from RTEMS dispatcher after the current
-task has been swapped out but before the new task has been
-swapped in.  A value of NULL indicates that no extension is
-provided.  As this routine is invoked after saving the current
-task's context and before restoring the heir task's context, it
-is not necessary for this routine to save and restore any
-registers.
-
- at item thread_begin
-is the address of the user-supplied
-subroutine which is invoked immediately before a task begins
-execution.  It is invoked in the context of the beginning task.
-A value of NULL indicates that no extension is provided.
-
- at item thread_exitted
-is the address of the user-supplied
-subroutine which is invoked when a task exits.  This procedure
-is responsible for some action which will allow the system to
-continue execution (i.e. delete or restart the task) or to
-terminate with a fatal error.  If this field is set to NULL, the
-default RTEMS TASK_EXITTED handler will be invoked.
-
- at item fatal
-is the address of the user-supplied
-subroutine for the FATAL extension.  This RTEMS extension of
-fatal error handling is called from the 
- at code{@value{DIRPREFIX}fatal_error_occurred}
-directive.  If the user's fatal error handler returns or if this
-entry is NULL then the default RTEMS fatal error handler will be
-executed.
-
- at end table
-
-A typical declaration for a User Extension Table
-which defines the TASK_CREATE, TASK_DELETE, TASK_SWITCH, and
-FATAL extension might appear as follows:
+ at item DEFAULT VALUE:
+This is not defined by default.
 
- at example
-rtems_extensions_table User_extensions = @{
-   task_create_extension,
-   NULL,
-   NULL,
-   task_delete_extension,
-   task_switch_extension,
-   NULL,
-   NULL,
-   fatal_extension
-@};
- at end example
+ at end table
 
-More information regarding the user extensions is
-provided in the User Extensions chapter.
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_HAS_OWN_MULTIPROCESSING_TABLE} is defined if the
+application wishes to provide their own Multiprocessing Configuration
+Table.  The generated table is named @code{Multiprocessing_configuration}.
 
- at subsection Multiprocessor Configuration Table
+ at subheading NOTES:
+This is a configuration parameter which is very unlikely to be used by
+an application. If you find yourself wanting to use it in an application,
+please reconsider and discuss this on the RTEMS Users mailing list.
 
- at cindex Multiprocessor Configuration Table
+ at c
+ at c === Ada Tasks ===
+ at c
+ at section Ada Tasks
 
-The Multiprocessor Configuration Table contains
-information needed when using RTEMS in a multiprocessor
-configuration.  Many of the details associated with configuring
-a multiprocessor system are dependent on the multiprocessor
-communications layer provided by the user.  The address of the
-Multiprocessor Configuration Table should be placed in the
- at code{User_multiprocessing_table} entry in the primary Configuration
-Table.  Further details regarding many of the entries in the
-Multiprocessor Configuration Table will be provided in the
-Multiprocessing chapter.  
+This section defines the system configuration parameters supported
+by @code{<rtems/confdefs.h>} related to configuring RTEMS to support
+a task using Ada tasking with GNAT/RTEMS.
 
+These configuration parameters are only available when RTEMS is built with
+the @code{--enable-ada} configure option and the application specifies
+ at code{CONFIGURE_GNAT_RTEMS}.
 
-When using the @code{rtems/confdefs.h} mechanism for configuring
-an RTEMS application, the macro @code{CONFIGURE_MP_APPLICATION} must
-be defined to automatically generate the Multiprocessor Configuration Table.
-If @code{CONFIGURE_MP_APPLICATION}, is not defined, then a NULL pointer
-is configured as the address of this table.
+Additionally RTEMS includes an Ada language binding to the Classic
+API which has a test suite. This test suite is enabled only when
+ at code{--enable-tests} and @code{--enable-expada} are specified on the
+configure command.
 
-The format of the Multiprocessor Configuration Table is defined in 
-the following C structure:
+ at c
+ at c === CONFIGURE_GNAT_RTEMS ===
+ at c
+ at subsection Specify Application Includes Ada Code
 
- at example
-typedef struct @{
-  uint32_t          node;
-  uint32_t          maximum_nodes;
-  uint32_t          maximum_global_objects;
-  uint32_t          maximum_proxies;
-  uint32_t          extra_mpci_receive_server_stack;
-  rtems_mpci_table *User_mpci_table;
-@} rtems_multiprocessing_table;
- at end example
+ at findex CONFIGURE_GNAT_RTEMS
 
 @table @b
- at item node
-is a unique processor identifier
-and is used in routing messages between nodes in a
-multiprocessor configuration.  Each processor must have a unique
-node number.  RTEMS assumes that node numbers start at one and
-increase sequentially.  This assumption can be used to advantage
-by the user-supplied MPCI layer.  Typically, this requirement is
-made when the node numbers are used to calculate the address of
-inter-processor communication links.  Zero should be avoided as
-a node number because some MPCI layers use node zero to
-represent broadcasted packets.  Thus, it is recommended that
-node numbers start at one and increase sequentially.
-When using the @code{rtems/confdefs.h} mechanism for configuring
-an RTEMS application, the value for this field corresponds
-to the setting of the macro @code{CONFIGURE_MP_NODE_NUMBER}.
-If not defined by the application, then the @code{CONFIGURE_MP_NODE_NUMBER}
-macro defaults to the value of the @code{NODE_NUMBER} macro which is
-set on the compiler command line by the RTEMS Multiprocessing Test Suites.
-
-
- at item maximum_nodes
-is the number of processor nodes in the system.
-When using the @code{rtems/confdefs.h} mechanism for configuring
-an RTEMS application, the value for this field corresponds
-to the setting of the macro @code{CONFIGURE_MP_MAXIMUM_NODES}.
-If not defined by the application, then the @code{CONFIGURE_MP_MAXIMUM_NODES}
-macro defaults to the value 2.
-
- at item maximum_global_objects
-is the maximum number of global objects which can exist at any
-given moment in the entire system.  If this parameter is not the
-same on all nodes in the system, then a fatal error is generated
-to inform the user that the system is inconsistent.
-When using the @code{rtems/confdefs.h} mechanism for configuring
-an RTEMS application, the value for this field corresponds
-to the setting of the macro @code{CONFIGURE_MP_MAXIMUM_GLOBAL_OBJECTS}.
-If not defined by the application, then the
- at code{CONFIGURE_MP_MAXIMUM_GLOBAL_OBJECTS} macro defaults to the value 32.
-
-
- at item maximum_proxies
-is the maximum number of proxies which can exist at any given moment
-on this particular node.  A proxy is a substitute task control block
-which represent a task residing on a remote node when that task blocks
-on a remote object.  Proxies are used in situations in which delayed
-interaction is required with a remote node.
-When using the @code{rtems/confdefs.h} mechanism for configuring
-an RTEMS application, the value for this field corresponds
-to the setting of the macro @code{CONFIGURE_MP_MAXIMUM_PROXIES}.
-If not defined by the application, then the @code{CONFIGURE_MP_MAXIMUM_PROXIES}
-macro defaults to the value 32.
-
- at item extra_mpci_receive_server_stack
-is the extra stack space allocated for the RTEMS MPCI receive server task
-in bytes.  The MPCI receive server may invoke nearly all directives and 
-may require extra stack space on some targets.
-
- at item User_mpci_table
-is the address of the Multiprocessor Communications Interface
-Table.  This table contains the entry points of user-provided functions
-which constitute the multiprocessor communications layer.  This table
-must be provided in multiprocessor configurations with all
-entries configured.  The format of this table and details
-regarding its entries can be found in the next section.
-When using the @code{rtems/confdefs.h} mechanism for configuring
-an RTEMS application, the value for this field corresponds
-to the setting of the macro @code{CONFIGURE_MP_MPCI_TABLE_POINTER}.
-If not defined by the application, then the
- at code{CONFIGURE_MP_MPCI_TABLE_POINTER} macro defaults to the 
-address of the table named @code{MPCI_table}.
-
-
- at end table
-
- at subsection Multiprocessor Communications Interface Table
-
- at cindex  Multiprocessor Communications Interface Table
-
-This table defines the set of callouts that must be provided by 
-an Multiprocessor Communications Interface implementation.  
-
-When using the @code{rtems/confdefs.h} mechanism for configuring
-an RTEMS application, the name of this table is assumed
-to be @code{MPCI_table} unless the application sets
-the @code{CONFIGURE_MP_MPCI_TABLE_POINTER} when configuring a
-multiprocessing system. 
-
-The format of this table is defined in 
-the following C structure:
+ at item CONSTANT:
+ at code{CONFIGURE_GNAT_RTEMS}
 
- at example
-typedef struct @{
-  uint32_t                        default_timeout; /* in ticks */
-  uint32_t                        maximum_packet_size;
-  rtems_mpci_initialization_entry initialization;
-  rtems_mpci_get_packet_entry     get_packet;
-  rtems_mpci_return_packet_entry  return_packet;
-  rtems_mpci_send_entry           send_packet;
-  rtems_mpci_receive_entry        receive_packet;
-@} rtems_mpci_table;
- at end example
+ at item DATA TYPE:
+Boolean feature macro.
 
- at table @b
- at item default_timeout
-is the default maximum length of time a task should block waiting for
-a response to a directive which results in communication with a remote node.
-The maximum length of time is a function the user supplied
-multiprocessor communications layer and the media used.  This
-timeout only applies to directives which would not block if the
-operation were performed locally.
-
- at item maximum_packet_size
-is the size in bytes of the longest packet which the MPCI layer is capable
-of sending.  This value should represent the total number of bytes available
-for a RTEMS interprocessor messages.
-
- at item initialization
-is the address of the entry point for the initialization procedure of the
-user supplied multiprocessor communications layer.
-
- at item get_packet
-is the address of the entry point for the procedure called by RTEMS to
-obtain a packet from the user supplied multiprocessor communications layer.
-
- at item return_packet
-is the address of the entry point for the procedure called by RTEMS to
-return a packet to the user supplied multiprocessor communications layer.
-
- at item send
-is the address of the entry point for the procedure called by RTEMS to
-send an envelope to another node.  This procedure is part of the user
-supplied multiprocessor communications layer.
-
- at item receive
-is the address of the entry point for the
-procedure called by RTEMS to retrieve an envelope containing a
-message from another node.  This procedure is part of the user
-supplied multiprocessor communications layer.
-
- at end table
-
-More information regarding the required functionality of these
-entry points is provided in the Multiprocessor chapter.
-
- at subsection Determining Memory Requirements
-
-Since memory is a critical resource in many real-time
-embedded systems, the RTEMS Classic API was specifically designed to allow
-unused managers to be forcibly excluded from the run-time environment.
-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
-result, the size of the RTEMS executive is application
-dependent.
-
-It is not necessary for RTEMS Application Developers to calculate
-the amount of memory required for the RTEMS Workspace.  This
-is done automatically by @code{<rtems/confdefs.h>}.  
-See @ref{Configuring a System Sizing the RTEMS RAM Workspace} for
-more details on how 
-this works.  In the event, you are interested in the memory required
-for an instance of a particular RTEMS object, please run the test
- at code{spsize} on your target board.
-
-RTEMS is built to be a library and any routines that you do not 
-directly or indirectly require in your application will @b{NOT}
-be included in your executable image.  However, some managers
-may be explicitly excluded and no attempt to create these instances
-of these objects will succeed even if they are configured.
-The following Classic API managers may be optionally excluded:
+ at item RANGE:
+Defined or undefined.
 
- at itemize @bullet
- at item signal
- at item region
- at item dual ported memory
- at item event
- at item multiprocessing
- at item partition
- at item timer
- at item semaphore
- at item message
- at item rate monotonic
- at end itemize
+ at item DEFAULT VALUE:
+This is not defined by default.
 
-RTEMS is designed to be built and installed as a library
-that is linked into the application.  As such, much of
-RTEMS is implemented in such a way that there is a single
-entry point per source file.  This avoids having the 
-linker being forced to pull large object files in their
-entirety into an application when the application references
-a single symbol.  In the event you discover an RTEMS method
-that is included in your executable but never entered, please
-let us know.  It might be an opportunity to break a dependency
-and shrink many RTEMS applications.
-
-RTEMS based applications must somehow provide memory
-for RTEMS' code and data space.  Although RTEMS' data space must
-be in RAM, its code space can be located in either ROM or RAM.
-In addition, the user must allocate RAM for the RTEMS RAM
-Workspace.  The size of this area is application dependent and
-can be calculated using the formula provided in the Memory
-Requirements chapter of the Applications Supplement document
-for a specific target processor.
-
-All private RTEMS data variables and routine names used by
-RTEMS begin with the underscore ( _ ) character followed by an
-upper-case letter.  If RTEMS is linked with an application, then
-the application code should NOT contain any symbols which begin
-with the underscore character and followed by an upper-case
-letter to avoid any naming conflicts.  All RTEMS directive names
-should be treated as reserved words.
-
- at subsection Sizing the RTEMS RAM Workspace
-
-The RTEMS RAM Workspace is a user-specified block of
-memory reserved for use by RTEMS.  The application should NOT
-modify this memory.  This area consists primarily of the RTEMS
-data structures whose exact size depends upon the values
-specified in the Configuration Table.  In addition, task stacks
-and floating point context areas are dynamically allocated from
-the RTEMS RAM Workspace.
-
-The @code{rtems/confdefs.h} mechanism calcalutes the size
-of the RTEMS RAM Workspace automatically.  It assumes that
-all tasks are floating point and that all will be allocated
-the miminum stack space.  This calculation also automatically
-includes the memory that will be allocated for internal use
-by RTEMS.  The following macros may be set
-by the application to make the calculation
-of memory required more accurate:
+ at end table
 
- at itemize @bullet
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_GNAT_RTEMS} is defined to inform RTEMS that the GNAT
+Ada run-time is to be used by the application.
 
- at item @code{CONFIGURE_MEMORY_OVERHEAD}
- at item @code{CONFIGURE_EXTRA_TASK_STACKS}
+ at subheading NOTES:
+This configuration parameter is critical as it makes
+ at code{<rtems/confdefs.h>} configure the resources (POSIX API Threads,
+Mutexes, Condition Variables, and Keys) used implicitly by the GNAT
+run-time.
 
- at end itemize
+ at c
+ at c === CONFIGURE_MAXIMUM_ADA_TASKS ===
+ at c
+ at subsection Specify the Maximum Number of Ada Tasks.
 
-The starting address of the RTEMS RAM Workspace must
-be aligned on a four-byte boundary.  Failure to properly align
-the workspace area will result in the 
- at code{@value{DIRPREFIX}fatal_error_occurred}
-directive being invoked with the
- at code{@value{RPREFIX}INVALID_ADDRESS} error code.
-
-The file @code{<rtems/confdefs.h>} will calculate the 
-value that is specified as the @code{work_space_size}
-parameter of the Configuration Table. There are many
-parameters the application developer can specify to
-help @code{<rtems/confdefs.h>} in its calculations.  Correctly
-specifying the application requirements via parameters
-such as @code{CONFIGURE_EXTRA_TASK_STACKS} and
- at code{CONFIGURE_MAXIMUM_TASKS} is critical for production software.
+ at findex CONFIGURE_MAXIMUM_ADA_TASKS
 
-The allocation of objects can operate in two modes. The default mode
-has an object number ceiling. No more than the specified number of
-objects can be allocated from the RTEMS RAM Workspace. The number of objects
-specified in the particular API Configuration table fields are
-allocated at initialisation. The second mode allows the number of
-objects to grow to use the available free memory in the RTEMS RAM Workspace.
-
-See @ref{Configuring a System Unlimited Objects} for more details
-about the second mode, which allows for dynamic allocation of objects
-and therefore does not provide determinism.
-This mode is useful mostly for when the number of objects cannot be
-determined ahead of time or when porting software for which you do not
-know the object requirements.
-
-Note that future versions of RTEMS may not have the
-same memory requirements per object. Although the value calculated is
-sufficient for a particular target processor and release of RTEMS,
-memory usage is subject to change across versions and target
-processors.  To avoid problems, users should accurately 
-specify each configuration parameter and allow
- at code{<rtems/confdefs.h>} to calculate the memory requirements.
-The memory requirements are likely to change each
-time one of the following events occurs:
+ at table @b
+ at item CONSTANT:
+ at code{CONFIGURE_MAXIMUM_ADA_TASKS}
 
- at itemize @bullet
- at item a configuration parameter is modified,
- at item task or interrupt stack requirements change,
- at item task floating point attribute is altered,
- at item RTEMS is upgraded, or
- at item the target processor is changed.
- at end itemize
+ at item DATA TYPE:
+integer
 
-Failure to provide enough space in the RTEMS RAM
-Workspace will result in the 
- at code{@value{DIRPREFIX}fatal_error_occurred} directive
-being invoked with the appropriate error code.
+ at item RANGE:
+undefined or positive
 
- at subsection Unlimited Objects
+ at item DEFAULT VALUE:
+By default, when @code{CONFIGURE_GNAT_RTEMS} is defined, this is set to 20.
 
-In real-time embedded systems the RAM is normally a limited, critical resource
-and dynamic allocation is avoided as much as possible to ensure predictable,
-deterministic execution times. For such cases,
-see @ref{Configuring a System Sizing the RTEMS RAM Workspace}
-for an overview of how to tune the size of the workspace.
-Frequently when users are porting software to RTEMS the precise resource
-requirements of the software is unknown. In these situations users do not
-need to control the size of the workspace very tightly because they just
-want to get the new software to run; later they can tune the workspace size
-as needed.
+ at end table
 
- at findex rtems_resource_unlimited
-When the number of objects is not known ahead of time, RTEMS provides an
-auto-extending mode that can be enabled individually for each object
-type by using the macro @code{rtems_resource_unlimited}. This takes a value
-as a parameter, and is used to set the object maximum number field in
-an API Configuration table. The value is an allocation unit size. When
-RTEMS is required to grow the object table it is grown by this
-size. The kernel will return the object memory back to the RTEMS RAM Workspace
-when an object is destroyed. The kernel will only return an allocated
-block of objects to the RTEMS RAM Workspace if at least half the allocation
-size of free objects remain allocated. RTEMS always keeps one
-allocation block of objects allocated. Here is an example of using 
- at code{rtems_resource_unlimited}:
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_MAXIMUM_ADA_TASKS} is the number of Ada tasks that can
+be concurrently active in the system.
 
- at example
-#define CONFIGURE_MAXIMUM_TASKS rtems_resource_unlimited(5)
- at end example
+ at subheading NOTES:
+None.
 
- at findex rtems_resource_is_unlimited
- at findex rtems_resource_maximum_per_allocation
-Object maximum specifications can be evaluated with the
- at code{rtems_resource_is_unlimited} and
- at code{rtems_resource_maximum_per_allocation} macros.
+ at c
+ at c === CONFIGURE_MAXIMUM_FAKE_ADA_TASKS ===
+ at c
+ at subsection Specify the Maximum Fake Ada Tasks
 
-To ease the burden of developers who are porting new software RTEMS also
-provides the following macros:
- at itemize @bullet
+ at findex CONFIGURE_MAXIMUM_FAKE_ADA_TASKS
 
- at findex CONFIGURE_OBJECTS_UNLIMITED
- at item @code{CONFIGURE_OBJECTS_UNLIMITED}
-uses @code{rtems_resource_unlimited} for classic and posix objects that
-do not already have a maximum limit defined.
+ at table @b
+ at item CONSTANT:
+ at findex CONFIGURE_MAXIMUM_FAKE_ADA_TASKS
 
- at findex CONFIGURE_OBJECTS_ALLOCATION_SIZE
- at item @code{CONFIGURE_OBJECTS_ALLOCATION_SIZE}
-provides an allocation size to use for @code{rtems_resource_unlimited} when
-using @code{CONFIGURE_OBJECTS_UNLIMITED}; the default value is 8.
+ at item DATA TYPE:
+integer
 
- at end itemize
+ at item RANGE:
+zero or positive
 
-By allowing users to declare all resources as being unlimited the user
-can avoid identifying and limiting the resources used.
- at code{CONFIGURE_OBJECTS_UNLIMITED} does not support varying
-the allocation sizes for different objects; users who want that
-much control can define the @code{rtems_resource_unlimited} macros themselves.
+ at item DEFAULT VALUE:
+By default, this is undefined which implies zero (0) @i{fake} Ada Tasks.
 
- at example
-#define CONFIGURE_OBJECTS_UNLIMITED
-#define CONFIGURE_OBJECTS_ALLOCATION_SIZE 5
- at end example
+ at end table
 
-Due to how the posix object memory requirements are configured the
-unlimited object support does not provide unlimited size declarations
-for posix keys or queued signals.
+ at subheading DESCRIPTION:
+ at code{CONFIGURE_MAXIMUM_FAKE_ADA_TASKS} is the number of @i{fake} Ada tasks
+that can be concurrently active in the system.  A @i{fake} Ada task is
+a non-Ada task that makes calls back into Ada code and thus implicitly
+uses the Ada run-time.
 
-Users are cautioned that using unlimited objects is not recommended for
-production software unless the dynamic growth is absolutely required.
+ at subheading NOTES:
+None.
+
+ at c
+ at c === Configuration Data Structures ===
+ at c
+ at section Configuration Data Structures
+
+It is recommended that applications be configured using
+ at code{<rtems/confdefs.h>} as it is simpler and insulates applications
+from changes in the underlying data structures.  However, it is sometimes
+important to understand the data structures that are automatically filled
+in by the configuration parameters.  This section describes the primary
+configuration data structures.
+
+If the user wishes to see the details of a particular data structure,
+they are are advised to look at the source code. After all, that is one
+of the advantages of RTEMS.




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