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diff --git a/ada_user/configuring_a_system.rst b/ada_user/configuring_a_system.rst deleted file mode 100644 index 0ca65f7..0000000 --- a/ada_user/configuring_a_system.rst +++ /dev/null @@ -1,5026 +0,0 @@ -Configuring a System -#################### - -.. COMMENT: === Introduction === - -Introduction -============ - -RTEMS must be configured for an application. This configuration -encompasses a variety of information including the length of each clock -tick, the maximum number of each information RTEMS object that can -be created, the application initialization tasks, 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 -by RTEMS at system initialization time, the data structures themselves -should only rarely to be generated by hand. RTEMS provides a set of -macros system which provides a simple standard mechanism to automate -the generation of these structures. - -System configuration is ALWAYS done from C. When developing -an Ada application, the user is responsible for creating at -least one C file which contains the Ada run-time initialization -and the RTEMS System Configuration. There is no Ada binding -for RTEMS System Configuration information. Thus all examples -and data structures shown in this chapter are in C... index:: confdefs.h -.. index:: confdefs.h -.. index:: <rtems/confdefs.h> -.. index:: <rtems/confdefs.h> - -The RTEMS header file ``<rtems/confdefs.h>`` is at 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: ``confdefs`` is shorthand for a *Configuration Defaults*. - -As a general rule, application developers only specify 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 compliant with the RTEID/ORKID -standards upon which the Classic API is based. There are similar cases -where the default is selected to be compliant with with the POSIX standard. - -For each configuration parameter in the configuration tables, the macro -corresponding to that field is discussed. The RTEMS Maintainers -expect that all systems can be easily configured using the``<rtems/confdefs.h>`` mechanism and that using this mechanism will -avoid internal RTEMS configuration changes impacting applications. - -.. COMMENT: === Philosophy === - -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 ``<rtems/confdefs.h>`` file ensures that at least one application -task or thread is configured and that at least one of the initialization -task/thread tables is configured. - -.. COMMENT: === Sizing the RTEMS Workspace === - - -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 ``<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 minimum stack space. This calculation -includes the amount of memory that will be allocated for internal use -by RTEMS. The automatic calculation may underestimate the workspace -size truly needed by the application, in which case one can use the``CONFIGURE_MEMORY_OVERHEAD`` macro to add a value to the estimate. See `Specify Memory Overhead`_ for more details. - -The memory area for the RTEMS Workspace is determined by the BSP. In case the -RTEMS Workspace is too large for the available memory, then a fatal run-time -error occurs and the system terminates. - -The file ``<rtems/confdefs.h>`` will calculate the value of the``work_space_size`` parameter of the Configuration Table. There -are many parameters the application developer can specify to -help ``<rtems/confdefs.h>`` in its calculations. Correctly -specifying the application requirements via parameters such as``CONFIGURE_EXTRA_TASK_STACKS`` and ``CONFIGURE_MAXIMUM_TASKS`` -is critical for production software. - -For each class of objects, the allocation can operate in one of two ways. -The default way has an ceiling on the maximum number of object instances -which can concurrently exist in the system. Memory for all instances of -that object class is reserved at system initialization. The second -way allocates memory for an initial number of objects and increases the -current allocation by a fixed increment when required. Both ways allocate -space from inside the RTEMS Workspace. - -See `Unlimited Objects`_ for more details about -the second way, 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. - -The space needed for stacks and for RTEMS objects will vary from -one version of RTEMS and from one target processor to another. -Therefore it is safest to use ``<rtems/confdefs.h>`` and specify -your application’s requirements in terms of the numbers of objects and -multiples of ``RTEMS_MINIMUM_STACK_SIZE``, as far as is possible. The -automatic estimates of space required will in general change when: - -- a configuration parameter is changed, - -- task or interrupt stack sizes change, - -- the floating point attribute of a task changes, - -- task floating point attribute is altered, - -- RTEMS is upgraded, or - -- the target processor is changed. - -Failure to provide enough space in the RTEMS Workspace may result in fatal -run-time errors terminating the system. - -.. COMMENT: === Potential Issues === - -Potential Issues with RTEMS Workspace Size Estimation -===================================================== - -The ``<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 ``<rtems/confdefs.h>`` and may be either -too high or too low for a variety of reasons. Some of the reasons that``<rtems/confdefs.h>`` may reserve too much memory for RTEMS are: - -- All tasks/threads are assumed to be floating point. - -Conversely, there are many more reasons that the resource estimate could be -too low: - -- Task/thread stacks greater than minimum size must be - accounted for explicitly by developer. - -- Memory for messages is not included. - -- Device driver requirements are not included. - -- Network stack requirements are not included. - -- Requirements for add-on libraries are not included. - -In general, ``<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. - -.. COMMENT: === Format to be followed for making changes in this file === - -Format to be followed for making changes in this file -===================================================== - -- MACRO NAME - Should be alphanumeric. Can have ’_’ (underscore). - -- DATA TYPE - Please refer to all existing formats. - -- RANGE: - The range depends on the Data Type of the macro. - - - − If the data type is of type task priority, then its value should - be an integer in the range of 1 to 255. - - - − If the data type is an integer, then it can have numbers, characters - (in case the value is defined using another macro) and arithmetic operations - (+, -, \*, /). - - - − If the data type is a function pointer the first character - should be an alphabet or an underscore. The rest of the string - can be alphanumeric. - - - − If the data type is RTEMS Attributes or RTEMS Mode then - the string should be alphanumeric. - - - − If the data type is RTEMS NAME then the value should be - an integer>=0 or RTEMS_BUILD_NAME( ’U’, ’I’, ’1’, ’ ’ ) - -- DEFAULT VALUE - The default value should be in the following formats- - Please note that the ’.’ (full stop) is necessary. - - - − In case the value is not defined then: - This is not defined by default. - - - − If we know the default value then: - The default value is XXX. - - - − If the default value is BSP Specific then: - This option is BSP specific. - -- DESCRIPTION - The description of the macro. (No specific format) - -- NOTES - Any further notes. (No specific format) - -.. COMMENT: === Configuration Example === - -Configuration Example -===================== - -In the following example, the configuration information for a system -with a single message queue, four (4) tasks, and a timeslice of -fifty (50) milliseconds is as follows: -.. code:: c - - #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_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(20, sizeof(struct USER_MESSAGE)) - #define CONFIGURE_INIT - #include <rtems/confdefs.h> - -In this example, only a few configuration parameters are specified. The -impact of these are as follows: - -- The example specified ``CONFIGURE_RTEMS_INIT_TASK_TABLE`` - but did not specify any additional parameters. This results in a - configuration of an application which will begin execution of a single - initialization task named ``Init`` which is non-preemptible and at - priority one (1). - -- By specifying ``CONFIGURE_APPLICATION_NEEDS_CLOCK_DRIVER``, - this application is configured to have a clock tick device - driver. Without a clock tick device driver, RTEMS has no way to know - that time is passing and will be unable to support delays and wall - time. Further configuration details about time are - provided. Per ``CONFIGURE_MICROSECONDS_PER_TICK`` and``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. - -- By specifying ``CONFIGURE_APPLICATION_NEEDS_CONSOLE_DRIVER``, - the application will include a console device driver. Although the - console device driver may support a combination of multiple serial - ports and display and keyboard combinations, it is only required to - provide a single device named ``/dev/console``. This device will - be used for Standard Input, Output and Error I/O Streams. Thus when``CONFIGURE_APPLICATION_NEEDS_CONSOLE_DRIVER`` is specified, implicitly - three (3) file descriptors are reserved for the Standard I/O Streams and - those file descriptors are associated with ``/dev/console`` during - initialization. All console devices are expected to support the POSIX*termios* interface. - -- The example above specifies via ``CONFIGURE_MAXIMUM_TASKS`` - that the application requires a maximum of four (4) - simultaneously existing Classic API tasks. Similarly, by specifying``CONFIGURE_MAXIMUM_MESSAGE_QUEUES``, there may be a maximum of only - one (1) concurrently existent Classic API message queues. - -- The most surprising configuration parameter in this example is the - use of ``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 ``struct USER_MESSAGE``. - -- The ``CONFIGURE_INIT`` constant must be defined in order to - make ``<rtems/confdefs.h>`` instantiate the configuration data - structures. This can only be defined in one source file per - application that includes ``<rtems/confdefs.h>`` or the symbol - table will be instantiated multiple times and linking errors - produced. - -This example illustrates that parameters have default values. Among -other things, the application implicitly used the following defaults: - -- All unspecified types of communications and synchronization objects - in the Classic and POSIX Threads API have maximums of zero (0). - -- The filesystem will be the default filesystem which is the In-Memory File - System (IMFS). - -- The application will have the default number of priority levels. - -- The minimum task stack size will be that recommended by RTEMS for - the target architecture. - -.. COMMENT: === Unlimited Objects === - - -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 `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 API-independent object classes can be configured in -unlimited mode: - -- POSIX Keys - -- POSIX Key Value Pairs - -The following object classes in the Classic API can be configured in -unlimited mode: - -- Tasks - -- Timers - -- Semaphores - -- Message Queues - -- Periods - -- Barriers - -- Partitions - -- Regions - -- Ports - -Additionally, the following object classes from the POSIX API can be -configured in unlimited mode: - -- Threads - -- Mutexes - -- Condition Variables - -- Timers - -- Message Queues - -- Message Queue Descriptors - -- Semaphores - -- Barriers - -- Read/Write Locks - -- Spinlocks - -The following object classes can *not* be configured in unlimited mode: - -- Drivers - -- File Descriptors - -- User Extensions - -- POSIX Queued Signals - -Due to the memory requirements of unlimited objects it is strongly recommended -to use them only in combination with the unified work areas. See `Separate or Unified Work Areas`_ for more information -on unified work areas. - -The following example demonstrates how the two simple configuration defines for -unlimited objects and unified works areas can replace many seperate -configuration defines for supported object classes: -.. code:: c - - #define CONFIGURE_APPLICATION_NEEDS_CLOCK_DRIVER - #define CONFIGURE_APPLICATION_NEEDS_CONSOLE_DRIVER - #define CONFIGURE_UNIFIED_WORK_AREAS - #define CONFIGURE_UNLIMITED_OBJECTS - #define CONFIGURE_RTEMS_INIT_TASKS_TABLE - #define CONFIGURE_INIT - #include <rtems/confdefs.h> - -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. - -.. COMMENT: === Per Object Class Unlimited Object Instances === - -Per Object Class Unlimited Object Instances -------------------------------------------- -.. index:: 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 ``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``rtems_resource_unlimited``: -.. code:: c - - #define CONFIGURE_MAXIMUM_TASKS rtems_resource_unlimited(5) - -.. index:: rtems_resource_is_unlimited -.. index:: rtems_resource_maximum_per_allocation - -Object maximum specifications can be evaluated with the``rtems_resource_is_unlimited`` and``rtems_resource_maximum_per_allocation`` macros. - -.. COMMENT: === Unlimited Object Instances === - -Unlimited Object Instances --------------------------- - -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. - -.. COMMENT: === CONFIGURE_UNLIMITED_OBJECTS === - -Enable Unlimited Object Instances ---------------------------------- -.. index:: CONFIGURE_UNLIMITED_OBJECTS - -*CONSTANT:* - ``CONFIGURE_UNLIMITED_OBJECTS`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -``CONFIGURE_UNLIMITED_OBJECTS`` enables ``rtems_resource_unlimited`` -mode for Classic API and POSIX API objects that do not already have a -specific maximum limit defined. - -**NOTES:** - -When using unlimited objects, it is common practice to also specify``CONFIGURE_UNIFIED_WORK_AREAS`` so the system operates with a single -pool of memory for both RTEMS and application memory allocations. - -.. COMMENT: === CONFIGURE_UNLIMITED_ALLOCATION_SIZE === - -Specify Unlimited Objects Allocation Size ------------------------------------------ - -*CONSTANT:* - ``CONFIGURE_UNLIMITED_ALLOCATION_SIZE`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Positive. - -*DEFAULT VALUE:* - If not defined and ``CONFIGURE_UNLIMITED_OBJECTS`` is defined, the - default value is eight (8). - -**DESCRIPTION:** - -``CONFIGURE_UNLIMITED_ALLOCATION_SIZE`` provides an -allocation size to use for ``rtems_resource_unlimited`` when using``CONFIGURE_UNLIMITED_OBJECTS``. - -**NOTES:** - -By allowing users to declare all resources as being unlimited -the user can avoid identifying and limiting the resources used.``CONFIGURE_UNLIMITED_OBJECTS`` does not support varying the allocation -sizes for different objects; users who want that much control can define -the ``rtems_resource_unlimited`` macros themselves. -.. code:: c - - #define CONFIGURE_UNLIMITED_OBJECTS - #define CONFIGURE_UNLIMITED_ALLOCATION_SIZE 5 - -.. COMMENT: === Classic API Configuration === - -Classic API Configuration -========================= - -This section defines the Classic API related system configuration -parameters supported by ``<rtems/confdefs.h>``. - -.. COMMENT: === CONFIGURE_MAXIMUM_TASKS === - -Specify Maximum Classic API Tasks ---------------------------------- -.. index:: CONFIGURE_MAXIMUM_TASKS - -*CONSTANT:* - ``CONFIGURE_MAXIMUM_TASKS`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Zero or positive. - -*DEFAULT VALUE:* - The default value is 0. - -**DESCRIPTION:** - -``CONFIGURE_MAXIMUM_TASKS`` is the maximum number of Classic API -Tasks that can be concurrently active. - -**NOTES:** - -This object class can be configured in unlimited allocation mode. - -The 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``CONFIGURE_EXTRA_TASK_STACKS`` is used to specify task stack -requirements *ABOVE* the minimum size required. See `Reserve Task/Thread Stack Memory Above Minimum`_ -for more information about ``CONFIGURE_EXTRA_TASK_STACKS``. - -The maximum number of POSIX threads is specified by``CONFIGURE_MAXIMUM_POSIX_THREADS``. - -.. COMMENT: XXX - Add xref to CONFIGURE_MAXIMUM_POSIX_THREADS. - -A future enhancement to ``<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. - -.. COMMENT: === CONFIGURE_MAXIMUM_TIMERS === - -Specify Maximum Classic API Timers ----------------------------------- -.. index:: CONFIGURE_MAXIMUM_TIMERS - -*CONSTANT:* - ``CONFIGURE_MAXIMUM_TIMERS`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Zero or positive. - -*DEFAULT VALUE:* - The default value is 0. - -**DESCRIPTION:** - -``CONFIGURE_MAXIMUM_TIMERS`` is the maximum number of Classic API -Timers that can be concurrently active. - -**NOTES:** - -This object class can be configured in unlimited allocation mode. - -.. COMMENT: === CONFIGURE_MAXIMUM_SEMAPHORES === - -Specify Maximum Classic API Semaphores --------------------------------------- -.. index:: CONFIGURE_MAXIMUM_SEMAPHORES - -*CONSTANT:* - ``CONFIGURE_MAXIMUM_SEMAPHORES`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Zero or positive. - -*DEFAULT VALUE:* - The default value is 0. - -**DESCRIPTION:** - -``CONFIGURE_MAXIMUM_SEMAPHORES`` is the maximum number of Classic -API Semaphores that can be concurrently active. - -**NOTES:** - -This object class can be configured in unlimited allocation mode. - -.. COMMENT: === CONFIGURE_MAXIMUM_MRSP_SEMAPHORES === - -Specify Maximum Classic API Semaphores usable with MrsP -------------------------------------------------------- -.. index:: CONFIGURE_MAXIMUM_MRSP_SEMAPHORES - -*CONSTANT:* - ``CONFIGURE_MAXIMUM_MRSP_SEMAPHORES`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Zero or positive. - -*DEFAULT VALUE:* - The default value is 0. - -**DESCRIPTION:** - -``CONFIGURE_MAXIMUM_MRSP_SEMAPHORES`` is the -maximum number of Classic API Semaphores using the Multiprocessor Resource -Sharing Protocol (MrsP) that can be concurrently active. - -**NOTES:** - -This configuration option is only used on SMP configurations. On uni-processor -configurations the Priority Ceiling Protocol is used for MrsP semaphores and -thus no extra memory is necessary. - -.. COMMENT: === CONFIGURE_MAXIMUM_MESSAGE_QUEUES === - -Specify Maximum Classic API Message Queues ------------------------------------------- -.. index:: CONFIGURE_MAXIMUM_MESSAGE_QUEUES - -*CONSTANT:* - ``CONFIGURE_MAXIMUM_MESSAGE_QUEUES`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Zero or positive. - -*DEFAULT VALUE:* - The default value is 0. - -**DESCRIPTION:** - -``CONFIGURE_MAXIMUM_MESSAGE_QUEUES`` is the maximum number of Classic -API Message Queues that can be concurrently active. - -**NOTES:** - -This object class can be configured in unlimited allocation mode. - -.. COMMENT: === CONFIGURE_MAXIMUM_BARRIERS === - -Specify Maximum Classic API Barriers ------------------------------------- -.. index:: CONFIGURE_MAXIMUM_BARRIERS - -*CONSTANT:* - ``CONFIGURE_MAXIMUM_BARRIERS`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Zero or positive. - -*DEFAULT VALUE:* - The default value is 0. - -**DESCRIPTION:** - -``CONFIGURE_MAXIMUM_BARRIERS`` is the maximum number of Classic -API Barriers that can be concurrently active. - -**NOTES:** - -This object class can be configured in unlimited allocation mode. - -.. COMMENT: === CONFIGURE_MAXIMUM_PERIODS === - -Specify Maximum Classic API Periods ------------------------------------ -.. index:: CONFIGURE_MAXIMUM_PERIODS - -*CONSTANT:* - ``CONFIGURE_MAXIMUM_PERIODS`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Zero or positive. - -*DEFAULT VALUE:* - The default value is 0. - -**DESCRIPTION:** - -``CONFIGURE_MAXIMUM_PERIODS`` is the maximum number of Classic -API Periods that can be concurrently active. - -**NOTES:** - -This object class can be configured in unlimited allocation mode. - -.. COMMENT: === CONFIGURE_MAXIMUM_PARTITIONS === - -Specify Maximum Classic API Partitions --------------------------------------- -.. index:: CONFIGURE_MAXIMUM_PARTITIONS - -*CONSTANT:* - ``CONFIGURE_MAXIMUM_PARTITIONS`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Zero or positive. - -*DEFAULT VALUE:* - The default value is 0. - -**DESCRIPTION:** - -``CONFIGURE_MAXIMUM_PARTITIONS`` is the maximum number of Classic -API Partitions that can be concurrently active. - -**NOTES:** - -This object class can be configured in unlimited allocation mode. - -.. COMMENT: === CONFIGURE_MAXIMUM_REGIONS === - -Specify Maximum Classic API Regions ------------------------------------ -.. index:: CONFIGURE_MAXIMUM_REGIONS - -*CONSTANT:* - ``CONFIGURE_MAXIMUM_REGIONS`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Zero or positive. - -*DEFAULT VALUE:* - The default value is 0. - -**DESCRIPTION:** - -``CONFIGURE_MAXIMUM_REGIONS`` is the maximum number of Classic -API Regions that can be concurrently active. - -**NOTES:** - -None. - -.. COMMENT: === CONFIGURE_MAXIMUM_PORTS === - -Specify Maximum Classic API Ports ---------------------------------- -.. index:: CONFIGURE_MAXIMUM_PORTS - -*CONSTANT:* - ``CONFIGURE_MAXIMUM_PORTS`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Zero or positive. - -*DEFAULT VALUE:* - The default value is 0. - -**DESCRIPTION:** - -``CONFIGURE_MAXIMUM_PORTS`` is the maximum number of Classic -API Ports that can be concurrently active. - -**NOTES:** - -This object class can be configured in unlimited allocation mode. - -.. COMMENT: === CONFIGURE_MAXIMUM_USER_EXTENSIONS === - -Specify Maximum Classic API User Extensions -------------------------------------------- -.. index:: CONFIGURE_MAXIMUM_USER_EXTENSIONS - -*CONSTANT:* - ``CONFIGURE_MAXIMUM_USER_EXTENSIONS`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Zero or positive. - -*DEFAULT VALUE:* - The default value is 0. - -**DESCRIPTION:** - -``CONFIGURE_MAXIMUM_USER_EXTENSIONS`` is the maximum number of Classic -API User Extensions that can be concurrently active. - -**NOTES:** - -This object class can be configured in unlimited allocation mode. - -.. COMMENT: === Classic API Initialization Task Configuration === - -Classic API Initialization Tasks Table Configuration -==================================================== - -The ``<rtems/confdefs.h>`` configuration system can automatically -generate an Initialization Tasks Table named``Initialization_tasks`` with a single entry. The following -parameters control the generation of that table. - -.. COMMENT: === CONFIGURE_RTEMS_INIT_TASKS_TABLE === - -Instantiate Classic API Initialization Task Table -------------------------------------------------- -.. index:: CONFIGURE_RTEMS_INIT_TASKS_TABLE - -*CONSTANT:* - ``CONFIGURE_RTEMS_INIT_TASKS_TABLE`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -``CONFIGURE_RTEMS_INIT_TASKS_TABLE`` is defined if the user wishes -to use a Classic RTEMS API Initialization Task Table. The table built by``<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. - -**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. - -.. COMMENT: === CONFIGURE_INIT_TASK_ENTRY_POINT === - -Specifying Classic API Initialization Task Entry Point ------------------------------------------------------- -.. index:: CONFIGURE_INIT_TASK_ENTRY_POINT - -*CONSTANT:* - ``CONFIGURE_INIT_TASK_ENTRY_POINT`` - -*DATA TYPE:* - Task entry function pointer (``rtems_task_entry``). - -*RANGE:* - Valid task entry function pointer. - -*DEFAULT VALUE:* - The default value is ``Init``. - -**DESCRIPTION:** - -``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. - -**NOTES:** - -The user must implement the function ``Init`` or the function name provided -in this configuration parameter. - -.. COMMENT: === CONFIGURE_INIT_TASK_NAME === - -Specifying Classic API Initialization Task Name ------------------------------------------------ -.. index:: CONFIGURE_INIT_TASK_NAME - -*CONSTANT:* - ``CONFIGURE_INIT_TASK_NAME`` - -*DATA TYPE:* - RTEMS Name (``rtems_name``). - -*RANGE:* - Any value. - -*DEFAULT VALUE:* - The default value is ``rtems_build_name( 'U', 'I', '1', ' ' )``. - -**DESCRIPTION:** - -``CONFIGURE_INIT_TASK_NAME`` is the name of the single initialization -task defined by the Classic API Initialization Tasks Table. - -**NOTES:** - -None. - -.. COMMENT: === CONFIGURE_INIT_TASK_STACK_SIZE === - -Specifying Classic API Initialization Task Stack Size ------------------------------------------------------ -.. index:: CONFIGURE_INIT_TASK_STACK_SIZE - -*CONSTANT:* - ``CONFIGURE_INIT_TASK_STACK_SIZE`` - -*DATA TYPE:* - Unsigned integer (``size_t``). - -*RANGE:* - Zero or positive. - -*DEFAULT VALUE:* - The default value is RTEMS_MINIMUM_STACK_SIZE. - -**DESCRIPTION:** - -``CONFIGURE_INIT_TASK_STACK_SIZE`` is the stack size of the single -initialization task defined by the Classic API Initialization Tasks Table. - -**NOTES:** - -If the stack size specified is greater than the configured minimum, -it must be accounted for in ``CONFIGURE_EXTRA_TASK_STACKS``. -See `Reserve Task/Thread Stack Memory Above Minimum`_ -for more information about ``CONFIGURE_EXTRA_TASK_STACKS``. - -.. COMMENT: === CONFIGURE_INIT_TASK_PRIORITY === - -Specifying Classic API Initialization Task Priority ---------------------------------------------------- -.. index:: CONFIGURE_INIT_TASK_PRIORITY - -*CONSTANT:* - ``CONFIGURE_INIT_TASK_PRIORITY`` - -*DATA TYPE:* - RTEMS Task Priority (``rtems_task_priority``). - -*RANGE:* - One (1) to CONFIGURE_MAXIMUM_PRIORITY. - -*DEFAULT VALUE:* - The default value is 1, which is the highest priority in the - Classic API. - -**DESCRIPTION:** - -``CONFIGURE_INIT_TASK_PRIORITY`` is the initial priority of the single -initialization task defined by the Classic API Initialization Tasks Table. - -**NOTES:** - -None. - -.. COMMENT: === CONFIGURE_INIT_TASK_ATTRIBUTES === - -Specifying Classic API Initialization Task Attributes ------------------------------------------------------ -.. index:: CONFIGURE_INIT_TASK_ATTRIBUTES - -*CONSTANT:* - ``CONFIGURE_INIT_TASK_ATTRIBUTES`` - -*DATA TYPE:* - RTEMS Attributes (``rtems_attribute``). - -*RANGE:* - Valid task attribute sets. - -*DEFAULT VALUE:* - The default value is ``RTEMS_DEFAULT_ATTRIBUTES``. - -**DESCRIPTION:** - -``CONFIGURE_INIT_TASK_ATTRIBUTES`` is the task attributes of the single -initialization task defined by the Classic API Initialization Tasks Table. - -**NOTES:** - -None. - -.. COMMENT: === CONFIGURE_INIT_TASK_INITIAL_MODES === - -Specifying Classic API Initialization Task Modes ------------------------------------------------- -.. index:: CONFIGURE_INIT_TASK_INITIAL_MODES - -*CONSTANT:* - ``CONFIGURE_INIT_TASK_INITIAL_MODES`` - -*DATA TYPE:* - RTEMS Mode (``rtems_mode``). - -*RANGE:* - Valid task mode sets. - -*DEFAULT VALUE:* - The default value is ``RTEMS_NO_PREEMPT``. - -**DESCRIPTION:** - -``CONFIGURE_INIT_TASK_INITIAL_MODES`` is the initial execution mode of -the single initialization task defined by the Classic API Initialization -Tasks Table. - -**NOTES:** - -None. - -.. COMMENT: === CONFIGURE_INIT_TASK_ARGUMENTS === - -Specifying Classic API Initialization Task Arguments ----------------------------------------------------- -.. index:: CONFIGURE_INIT_TASK_ARGUMENTS - -*CONSTANT:* - ``CONFIGURE_INIT_TASK_ARGUMENTS`` - -*DATA TYPE:* - RTEMS Task Argument (``rtems_task_argument``). - -*RANGE:* - Complete range of the type. - -*DEFAULT VALUE:* - The default value is 0. - -**DESCRIPTION:** - -``CONFIGURE_INIT_TASK_ARGUMENTS`` is the task argument of the single -initialization task defined by the Classic API Initialization Tasks Table. - -**NOTES:** - -None. - -.. COMMENT: === CONFIGURE_HAS_OWN_INIT_TASK_TABLE === - -Not Using Generated Initialization Tasks Table ----------------------------------------------- -.. index:: CONFIGURE_HAS_OWN_INIT_TASK_TABLE - -*CONSTANT:* - ``CONFIGURE_HAS_OWN_INIT_TASK_TABLE`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -``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 ``Initialization_tasks``. - -**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. - -.. COMMENT: === POSIX API Configuration === - -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 ``--enable-posix`` option. - -.. COMMENT: === CONFIGURE_MAXIMUM_POSIX_THREADS === - -Specify Maximum POSIX API Threads ---------------------------------- -.. index:: CONFIGURE_MAXIMUM_POSIX_THREADS - -*CONSTANT:* - ``CONFIGURE_MAXIMUM_POSIX_THREADS`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Zero or positive. - -*DEFAULT VALUE:* - The default value is 0. - -**DESCRIPTION:** - -``CONFIGURE_MAXIMUM_POSIX_THREADS`` is the maximum number of POSIX API -Threads that can be concurrently active. - -**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``CONFIGURE_EXTRA_TASK_STACKS`` is used to specify thread stack -requirements *ABOVE* the minimum size required. -See `Reserve Task/Thread Stack Memory Above Minimum`_ -for more information about ``CONFIGURE_EXTRA_TASK_STACKS``. - -The maximum number of Classic API Tasks is specified by``CONFIGURE_MAXIMUM_TASKS``. - -All POSIX threads have floating point enabled. - -.. COMMENT: XXX - Add xref to CONFIGURE_MAXIMUM_TASKS. - -.. COMMENT: === CONFIGURE_MAXIMUM_POSIX_MUTEXES === - -Specify Maximum POSIX API Mutexes ---------------------------------- -.. index:: CONFIGURE_MAXIMUM_POSIX_MUTEXES - -*CONSTANT:* - ``CONFIGURE_MAXIMUM_POSIX_MUTEXES`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Zero or positive. - -*DEFAULT VALUE:* - The default value is 0. - -**DESCRIPTION:** - -``CONFIGURE_MAXIMUM_POSIX_MUTEXES`` is the maximum number of POSIX -API Mutexes that can be concurrently active. - -**NOTES:** - -This object class can be configured in unlimited allocation mode. - -.. COMMENT: === CONFIGURE_MAXIMUM_POSIX_CONDITION_VARIABLES === - -Specify Maximum POSIX API Condition Variables ---------------------------------------------- -.. index:: CONFIGURE_MAXIMUM_POSIX_CONDITION_VARIABLES - -*CONSTANT:* - ``CONFIGURE_MAXIMUM_POSIX_CONDITION_VARIABLES`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Zero or positive. - -*DEFAULT VALUE:* - The default value is 0. - -**DESCRIPTION:** - -``CONFIGURE_MAXIMUM_POSIX_CONDITION_VARIABLES`` is the maximum number -of POSIX API Condition Variables that can be concurrently active. - -**NOTES:** - -This object class can be configured in unlimited allocation mode. - -.. COMMENT: === CONFIGURE_MAXIMUM_POSIX_KEYS === - -Specify Maximum POSIX API Keys ------------------------------- -.. index:: CONFIGURE_MAXIMUM_POSIX_KEYS - -*CONSTANT:* - ``CONFIGURE_MAXIMUM_POSIX_KEYS`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Zero or positive. - -*DEFAULT VALUE:* - The default value is 0. - -**DESCRIPTION:** - -``CONFIGURE_MAXIMUM_POSIX_KEYS`` is the maximum number of POSIX -API Keys that can be concurrently active. - -**NOTES:** - -This object class can be configured in unlimited allocation mode. - -.. COMMENT: XXX - Key pairs - -.. COMMENT: === CONFIGURE_MAXIMUM_POSIX_TIMERS === - -Specify Maximum POSIX API Timers --------------------------------- -.. index:: CONFIGURE_MAXIMUM_POSIX_TIMERS - -*CONSTANT:* - ``CONFIGURE_MAXIMUM_POSIX_TIMERS`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Zero or positive. - -*DEFAULT VALUE:* - The default value is 0. - -**DESCRIPTION:** - -``CONFIGURE_MAXIMUM_POSIX_TIMERS`` is the maximum number of POSIX -API Timers that can be concurrently active. - -**NOTES:** - -This object class can be configured in unlimited allocation mode. - -.. COMMENT: === CONFIGURE_MAXIMUM_POSIX_QUEUED_SIGNALS === - -Specify Maximum POSIX API Queued Signals ----------------------------------------- -.. index:: CONFIGURE_MAXIMUM_POSIX_QUEUED_SIGNALS - -*CONSTANT:* - ``CONFIGURE_MAXIMUM_POSIX_QUEUED_SIGNALS`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Zero or positive. - -*DEFAULT VALUE:* - The default value is 0. - -**DESCRIPTION:** - -``CONFIGURE_MAXIMUM_POSIX_QUEUED_SIGNALS`` is the maximum number of POSIX -API Queued Signals that can be concurrently active. - -**NOTES:** - -None. - -.. COMMENT: === CONFIGURE_MAXIMUM_POSIX_MESSAGE_QUEUES === - -Specify Maximum POSIX API Message Queues ----------------------------------------- -.. index:: CONFIGURE_MAXIMUM_POSIX_MESSAGE_QUEUES - -*CONSTANT:* - ``CONFIGURE_MAXIMUM_POSIX_MESSAGE_QUEUES`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Zero or positive. - -*DEFAULT VALUE:* - The default value is 0. - -**DESCRIPTION:** - -``CONFIGURE_MAXIMUM_POSIX_MESSAGE_QUEUES`` is the maximum number of POSIX -API Message Queues that can be concurrently active. - -**NOTES:** - -This object class can be configured in unlimited allocation mode. - -.. COMMENT: XXX - memory for buffers note - -.. COMMENT: === CONFIGURE_MAXIMUM_POSIX_MESSAGE_QUEUE_DESCRIPTORS === - -Specify Maximum POSIX API Message Queue Descriptors ---------------------------------------------------- -.. index:: CONFIGURE_MAXIMUM_POSIX_MESSAGE_QUEUE_DESCRIPTORS - -*CONSTANT:* - ``CONFIGURE_MAXIMUM_POSIX_MESSAGE_QUEUE_DESCRIPTORS`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - greater than or equal to ``CONFIGURE_MAXIMUM_POSIX_MESSAGES_QUEUES`` - -*DEFAULT VALUE:* - The default value is 0. - -**DESCRIPTION:** - -``CONFIGURE_MAXIMUM_POSIX_MESSAGE_QUEUE_DESCRIPTORS`` is the maximum -number of POSIX API Message Queue Descriptors that can be concurrently -active. - -**NOTES:** - -This object class can be configured in unlimited allocation mode. - -``CONFIGURE_MAXIMUM_POSIX_MESSAGE_QUEUE_DESCRIPTORS`` should be -greater than or equal to ``CONFIGURE_MAXIMUM_POSIX_MESSAGE_QUEUES``. - -.. COMMENT: === CONFIGURE_MAXIMUM_POSIX_SEMAPHORES === - -Specify Maximum POSIX API Semaphores ------------------------------------- -.. index:: CONFIGURE_MAXIMUM_POSIX_SEMAPHORES - -*CONSTANT:* - ``CONFIGURE_MAXIMUM_POSIX_SEMAPHORES`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Zero or positive. - -*DEFAULT VALUE:* - The default value is 0. - -**DESCRIPTION:** - -``CONFIGURE_MAXIMUM_POSIX_SEMAPHORES`` is the maximum number of POSIX -API Semaphores that can be concurrently active. - -**NOTES:** - -None. - -.. COMMENT: === CONFIGURE_MAXIMUM_POSIX_BARRIERS === - -Specify Maximum POSIX API Barriers ----------------------------------- -.. index:: CONFIGURE_MAXIMUM_POSIX_BARRIERS - -*CONSTANT:* - ``CONFIGURE_MAXIMUM_POSIX_BARRIERS`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Zero or positive. - -*DEFAULT VALUE:* - The default value is 0. - -**DESCRIPTION:** - -``CONFIGURE_MAXIMUM_POSIX_BARRIERS`` is the maximum number of POSIX -API Barriers that can be concurrently active. - -**NOTES:** - -This object class can be configured in unlimited allocation mode. - -.. COMMENT: === CONFIGURE_MAXIMUM_POSIX_SPINLOCKS === - -Specify Maximum POSIX API Spinlocks ------------------------------------ -.. index:: CONFIGURE_MAXIMUM_POSIX_SPINLOCKS - -*CONSTANT:* - ``CONFIGURE_MAXIMUM_POSIX_SPINLOCKS`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Zero or positive. - -*DEFAULT VALUE:* - The default value is 0. - -**DESCRIPTION:** - -``CONFIGURE_MAXIMUM_POSIX_SPINLOCKS`` is the maximum number of POSIX -API Spinlocks that can be concurrently active. - -**NOTES:** - -This object class can be configured in unlimited allocation mode. - -.. COMMENT: === CONFIGURE_MAXIMUM_POSIX_RWLOCKS === - -Specify Maximum POSIX API Read/Write Locks ------------------------------------------- -.. index:: CONFIGURE_MAXIMUM_POSIX_RWLOCKS - -*CONSTANT:* - ``CONFIGURE_MAXIMUM_POSIX_RWLOCKS`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Zero or positive. - -*DEFAULT VALUE:* - The default value is 0. - -**DESCRIPTION:** - -``CONFIGURE_MAXIMUM_POSIX_RWLOCKS`` is the maximum number of POSIX -API Read/Write Locks that can be concurrently active. - -**NOTES:** - -This object class can be configured in unlimited allocation mode. - -.. COMMENT: === POSIX Initialization Threads Table Configuration === - -POSIX Initialization Threads Table Configuration -================================================ - -The ``<rtems/confdefs.h>`` configuration system can automatically -generate a POSIX Initialization Threads Table named``POSIX_Initialization_threads`` with a single entry. The following -parameters control the generation of that table. - -.. COMMENT: === CONFIGURE_POSIX_INIT_THREAD_TABLE === - -Instantiate POSIX API Initialization Thread Table -------------------------------------------------- -.. index:: CONFIGURE_POSIX_INIT_THREAD_TABLE - -*CONSTANT:* - .. index:: CONFIGURE_POSIX_INIT_THREAD_TABLE - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This field is not defined by default, as the user MUST select their own - API for initialization tasks. - -**DESCRIPTION:** - -``CONFIGURE_POSIX_INIT_THREAD_TABLE`` is defined if the user wishes -to use a POSIX API Initialization Threads Table. The table built -by ``<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. - -**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. - -.. COMMENT: === CONFIGURE_POSIX_INIT_THREAD_ENTRY_POINT === - -Specifying POSIX API Initialization Thread Entry Point ------------------------------------------------------- -.. index:: CONFIGURE_POSIX_INIT_THREAD_ENTRY_POINT - -*CONSTANT:* - ``CONFIGURE_POSIX_INIT_THREAD_ENTRY_POINT`` - -*DATA TYPE:* - POSIX thread function pointer (``void \*(*entry_point)(void \*)``). - -*RANGE:* - Undefined or a valid POSIX thread function pointer. - -*DEFAULT VALUE:* - The default value is ``POSIX_Init``. - -**DESCRIPTION:** - -``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. - -**NOTES:** - -The user must implement the function ``POSIX_Init`` or the function name -provided in this configuration parameter. - -.. COMMENT: === CONFIGURE_POSIX_INIT_THREAD_STACK_SIZE === - -Specifying POSIX API Initialization Thread Stack Size ------------------------------------------------------ -.. index:: CONFIGURE_POSIX_INIT_THREAD_STACK_SIZE - -*CONSTANT:* - ``CONFIGURE_POSIX_INIT_THREAD_STACK_SIZE`` - -*DATA TYPE:* - Unsigned integer (``size_t``). - -*RANGE:* - Zero or positive. - -*DEFAULT VALUE:* - The default value is 2 * RTEMS_MINIMUM_STACK_SIZE. - -**DESCRIPTION:** - -``CONFIGURE_POSIX_INIT_THREAD_STACK_SIZE`` is the stack size of the -single initialization thread defined by the POSIX API Initialization -Threads Table. - -**NOTES:** - -If the stack size specified is greater than the configured minimum, -it must be accounted for in ``CONFIGURE_EXTRA_TASK_STACKS``. -See `Reserve Task/Thread Stack Memory Above Minimum`_ -for more information about ``CONFIGURE_EXTRA_TASK_STACKS``. - -.. COMMENT: === CONFIGURE_POSIX_HAS_OWN_INIT_THREAD_TABLE === - -Not Using Generated POSIX Initialization Threads Table ------------------------------------------------------- -.. index:: CONFIGURE_POSIX_HAS_OWN_INIT_THREAD_TABLE - -*CONSTANT:* - ``CONFIGURE_POSIX_HAS_OWN_INIT_THREAD_TABLE`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -``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 ``POSIX_Initialization_threads``. - -**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. - -.. COMMENT: === Basic System Information === - -Basic System Information -======================== - -This section defines the general system configuration parameters supported by``<rtems/confdefs.h>``. - -.. COMMENT: === CONFIGURE_UNIFIED_WORK_AREAS === - - -Separate or Unified Work Areas ------------------------------- -.. index:: CONFIGURE_UNIFIED_WORK_AREAS -.. index:: unified work areas -.. index:: separate work areas -.. index:: RTEMS Workspace -.. index:: C Program Heap - -*CONSTANT:* - ``CONFIGURE_UNIFIED_WORK_AREAS`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default, which specifies that the C Program Heap - and the RTEMS Workspace will be separate. - -**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. - -**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. - -.. COMMENT: === CONFIGURE_MICROSECONDS_PER_TICK === - -Length of Each Clock Tick -------------------------- -.. index:: CONFIGURE_MICROSECONDS_PER_TICK -.. index:: tick quantum - -*CONSTANT:* - ``CONFIGURE_MICROSECONDS_PER_TICK`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Positive. - -*DEFAULT VALUE:* - This is not defined by default. When not defined, - the clock tick quantum is configured to be 10,000 - microseconds which is ten (10) milliseconds. - -**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. - -**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. - -.. COMMENT: === CONFIGURE_TICKS_PER_TIMESLICE === - -Specifying Timeslicing Quantum ------------------------------- -.. index:: CONFIGURE_TICKS_PER_TIMESLICE -.. index:: ticks per timeslice - -*CONSTANT:* - ``CONFIGURE_TICKS_PER_TIMESLICE`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Positive. - -*DEFAULT VALUE:* - The default value is 50. - -**DESCRIPTION:** - -This configuration parameter specifies the length of the timeslice -quantum in ticks for each task. - -**NOTES:** - -This configuration parameter has no impact if the Clock Tick Device -driver is not configured. - -.. COMMENT: === CONFIGURE_MAXIMUM_PRIORITY === - -Specifying the Number of Thread Priority Levels ------------------------------------------------ -.. index:: CONFIGURE_MAXIMUM_PRIORITY -.. index:: maximum priority -.. index:: number of priority levels - -*CONSTANT:* - ``CONFIGURE_MAXIMUM_PRIORITY`` - -*DATA TYPE:* - Unsigned integer (``uint8_t``). - -*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. - -*DEFAULT VALUE:* - The default value is 255, because RTEMS must support 256 priority levels to be - compliant with various standards. These priorities range from zero (0) to 255. - -**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. - -**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. - -.. COMMENT: === CONFIGURE_MINIMUM_TASK_STACK_SIZE === - -Specifying the Minimum Task Size --------------------------------- -.. index:: CONFIGURE_MINIMUM_TASK_STACK_SIZE -.. index:: minimum task stack size - -*CONSTANT:* - ``CONFIGURE_MINIMUM_TASK_STACK_SIZE`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Positive. - -*DEFAULT VALUE:* - This is not defined by default, which sets the executive to the recommended - minimum stack size for this processor. - -**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. - -**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. - -.. COMMENT: === CONFIGURE_INTERRUPT_STACK_SIZE === - -Configuring the Size of the Interrupt Stack -------------------------------------------- -.. index:: CONFIGURE_INTERRUPT_STACK_SIZE -.. index:: interrupt stack size - -*CONSTANT:* - ``CONFIGURE_INTERRUPT_STACK_SIZE`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Positive. - -*DEFAULT VALUE:* - The default value is CONFIGURE_MINIMUM_TASK_STACK_SIZE, which is the minimum - interrupt stack size. - -**DESCRIPTION:** - -``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. - -**NOTES:** - -In some BSPs, changing this constant does NOT change the -size of the interrupt stack, only the amount of memory -reserved for it. - -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. - -.. COMMENT: === CONFIGURE_EXTRA_TASK_STACKS === - - -Reserve Task/Thread Stack Memory Above Minimum ----------------------------------------------- -.. index:: CONFIGURE_EXTRA_TASK_STACKS -.. index:: memory for task tasks - -*CONSTANT:* - ``CONFIGURE_EXTRA_TASK_STACKS`` - -*DATA TYPE:* - Unsigned integer (``size_t``). - -*RANGE:* - Undefined or positive. - -*DEFAULT VALUE:* - The default value is 0. - -**DESCRIPTION:** - -This configuration parameter is set to the number of bytes the -applications wishes to add to the task stack requirements calculated -by ``<rtems/confdefs.h>``. - -**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 ``<rtems/confdefs.h>``. - -.. COMMENT: === CONFIGURE_ZERO_WORKSPACE_AUTOMATICALLY === - -Automatically Zeroing the RTEMS Workspace and C Program Heap ------------------------------------------------------------- -.. index:: CONFIGURE_ZERO_WORKSPACE_AUTOMATICALLY -.. index:: clear C Program Heap -.. index:: clear RTEMS Workspace -.. index:: zero C Program Heap -.. index:: zero RTEMS Workspace - -*CONSTANT:* - ``CONFIGURE_ZERO_WORKSPACE_AUTOMATICALLY`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default, unless overridden by the BSP. - The default is *NOT* to zero out the RTEMS Workspace or C Program Heap. - -**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. - -**NOTES:** - -Zeroing memory can add significantly to system boot time. It is not -necessary for RTEMS but is often assumed by support libraries. - -.. COMMENT: === CONFIGURE_STACK_CHECKER_ENABLED === - -Enable The Task Stack Usage Checker ------------------------------------ -.. index:: CONFIGURE_STACK_CHECKER_ENABLED - -*CONSTANT:* - ``CONFIGURE_STACK_CHECKER_ENABLED`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default, and thus stack checking is disabled. - -**DESCRIPTION:** - -This configuration parameter is defined when the application wishes to -enable run-time stack bounds checking. - -**NOTES:** - -In 4.9 and older, this configuration parameter was named``STACK_CHECKER_ON``. - -This increases the time required to create tasks as well as adding -overhead to each context switch. - -.. COMMENT: === CONFIGURE_INITIAL_EXTENSIONS === - -Specify Application Specific User Extensions --------------------------------------------- -.. index:: CONFIGURE_INITIAL_EXTENSIONS - -*CONSTANT:* - ``CONFIGURE_INITIAL_EXTENSIONS`` - -*DATA TYPE:* - List of user extension initializers (``rtems_extensions_table``). - -*RANGE:* - Undefined or a list of one or more user extensions. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -If ``CONFIGURE_INITIAL_EXTENSIONS`` is defined by the application, -then this application specific set of initial extensions will be placed -in the initial extension table. - -**NOTES:** - -None. - -.. COMMENT: === Custom Stack Allocator === - -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. - -.. COMMENT: === CONFIGURE_TASK_STACK_ALLOCATOR_INIT === - -Custom Task Stack Allocator Initialization ------------------------------------------- -.. index:: CONFIGURE_TASK_STACK_ALLOCATOR_INIT - -*CONSTANT:* - ``CONFIGURE_TASK_STACK_ALLOCATOR_INIT`` - -*DATA TYPE:* - Function pointer. - -*RANGE:* - Undefined, NULL or valid function pointer. - -*DEFAULT VALUE:* - The default value is NULL, which indicates that - task stacks will be allocated from the RTEMS Workspace. - -**DESCRIPTION:** - -``CONFIGURE_TASK_STACK_ALLOCATOR_INIT`` configures the initialization -method for an application or BSP specific task stack allocation -implementation. - -**NOTES:** - -A correctly configured system must configure the following to be consistent: - -- ``CONFIGURE_TASK_STACK_ALLOCATOR_INIT`` - -- ``CONFIGURE_TASK_STACK_ALLOCATOR`` - -- ``CONFIGURE_TASK_STACK_DEALLOCATOR`` - -.. COMMENT: === CONFIGURE_TASK_STACK_ALLOCATOR === - -Custom Task Stack Allocator ---------------------------- -.. index:: CONFIGURE_TASK_STACK_ALLOCATOR - -.. index:: task stack allocator - -*CONSTANT:* - ``CONFIGURE_TASK_STACK_ALLOCATOR`` - -*DATA TYPE:* - Function pointer. - -*RANGE:* - Undefined or valid function pointer. - -*DEFAULT VALUE:* - The default value is ``_Workspace_Allocate``, which indicates - that task stacks will be allocated from the RTEMS Workspace. - -**DESCRIPTION:** - -``CONFIGURE_TASK_STACK_ALLOCATOR`` may point to a user provided -routine to allocate task stacks. - -**NOTES:** - -A correctly configured system must configure the following to be consistent: - -- ``CONFIGURE_TASK_STACK_ALLOCATOR_INIT`` - -- ``CONFIGURE_TASK_STACK_ALLOCATOR`` - -- ``CONFIGURE_TASK_STACK_DEALLOCATOR`` - -.. COMMENT: === CONFIGURE_TASK_STACK_DEALLOCATOR === - -Custom Task Stack Deallocator ------------------------------ -.. index:: CONFIGURE_TASK_STACK_DEALLOCATOR -.. index:: task stack deallocator - -*CONSTANT:* - ``CONFIGURE_TASK_STACK_DEALLOCATOR`` - -*DATA TYPE:* - Function pointer. - -*RANGE:* - Undefined or valid function pointer. - -*DEFAULT VALUE:* - The default value is ``_Workspace_Free``, which indicates that - task stacks will be allocated from the RTEMS Workspace. - -**DESCRIPTION:** - -``CONFIGURE_TASK_STACK_DEALLOCATOR`` may point to a user provided -routine to free task stacks. - -**NOTES:** - -A correctly configured system must configure the following to be consistent: - -- ``CONFIGURE_TASK_STACK_ALLOCATOR_INIT`` - -- ``CONFIGURE_TASK_STACK_ALLOCATOR`` - -- ``CONFIGURE_TASK_STACK_DEALLOCATOR`` - -.. COMMENT: === Classic API Message Buffers === - -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. - -.. COMMENT: === CONFIGURE_MESSAGE_BUFFERS_FOR_QUEUE === - -Calculate Memory for a Single Classic Message API Message Queue ---------------------------------------------------------------- -.. index:: CONFIGURE_MESSAGE_BUFFERS_FOR_QUEUE -.. index:: memory for a single message queue’s buffers - -*CONSTANT:* - ``CONFIGURE_MESSAGE_BUFFERS_FOR_QUEUE(max_messages, size_per)`` - -*DATA TYPE:* - Unsigned integer (``size_t``). - -*RANGE:* - Positive. - -*DEFAULT VALUE:* - The default value is None. - -**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: -.. code:: c - - CONFIGURE_MESSAGE_BUFFERS_FOR_QUEUE(max_messages, size_per) - -Where ``max_messages`` is the maximum number of pending messages -and ``size_per`` is the size in bytes of the user message. - -**NOTES:** - -This macro is only used in support of ``CONFIGURE_MESSAGE_BUFFER_MEMORY``. - -.. COMMENT: === CONFIGURE_MESSAGE_BUFFER_MEMORY === - -Reserve Memory for All Classic Message API Message Queues ---------------------------------------------------------- -.. index:: CONFIGURE_MESSAGE_BUFFER_MEMORY -.. index:: configure message queue buffer memory - -*CONSTANT:* - ``CONFIGURE_MESSAGE_BUFFER_MEMORY`` - -*DATA TYPE:* - integer summation macro - -*RANGE:* - undefined (zero) or calculation resulting in a positive integer - -*DEFAULT VALUE:* - This is not defined by default, and zero (0) memory is reserved. - -**DESCRIPTION:** - -This macro is set to the number of bytes the application requires to be -reserved for pending Classic API Message Queue buffers. - -**NOTES:** - -The following illustrates how the help macro``CONFIGURE_MESSAGE_BUFFERS_FOR_QUEUE`` can be used to assist in -calculating the message buffer memory required. In this example, there -are two message queues used in this application. The first message -queue has maximum of 24 pending messages with the message structure -defined by the type ``one_message_type``. The other message queue -has maximum of 500 pending messages with the message structure defined -by the type ``other_message_type``. -.. code:: c - - #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) \\ - ) - -.. COMMENT: === Seldom Used Configuration Parameters === - -Seldom Used Configuration Parameters -==================================== - -This section describes configuration parameters supported by``<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``<rtems/confdefs.h>`` is incorrect. - -.. COMMENT: === CONFIGURE_MEMORY_OVERHEAD === - - -Specify Memory Overhead ------------------------ -.. index:: CONFIGURE_MEMORY_OVERHEAD - -*CONSTANT:* - ``CONFIGURE_MEMORY_OVERHEAD`` - -*DATA TYPE:* - Unsigned integer (``size_t``). - -*RANGE:* - Zero or positive. - -*DEFAULT VALUE:* - The default value is 0. - -**DESCRIPTION:** - -Thie parameter is set to the number of kilobytes the application wishes -to add to the requirements calculated by ``<rtems/confdefs.h>``. - -**NOTES:** - -This configuration parameter should only be used when it is suspected that -a bug in ``<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. - -.. COMMENT: === CONFIGURE_HAS_OWN_CONFIGURATION_TABLE === - -Do Not Generate Configuration Information ------------------------------------------ -.. index:: CONFIGURE_HAS_OWN_CONFIGURATION_TABLE - -*CONSTANT:* - ``CONFIGURE_HAS_OWN_CONFIGURATION_TABLE`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -This configuration parameter should only be defined if the application -is providing their own complete set of configuration tables. - -**NOTES:** - -None. - -.. COMMENT: === C Library Support Configuration === - -C Library Support Configuration -=============================== - -This section defines the file system and IO library -related configuration parameters supported by``<rtems/confdefs.h>``. - -.. COMMENT: === CONFIGURE_LIBIO_MAXIMUM_FILE_DESCRIPTORS === - -Specify Maximum Number of File Descriptors ------------------------------------------- -.. index:: CONFIGURE_LIBIO_MAXIMUM_FILE_DESCRIPTORS -.. index:: maximum file descriptors - -*CONSTANT:* - ``CONFIGURE_LIBIO_MAXIMUM_FILE_DESCRIPTORS`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Zero or positive. - -*DEFAULT VALUE:* - If ``CONFIGURE_APPLICATION_NEEDS_CONSOLE_DRIVER`` is defined, then the - default value is 3, otherwise the default value is 0. - Three file descriptors allows RTEMS to support standard input, output, and - error I/O streams on ``/dev/console``. - -**DESCRIPTION:** - -This configuration parameter is set to the maximum number of file like objects -that can be concurrently open. - -**NOTES:** - -None. - -.. COMMENT: === CONFIGURE_TERMIOS_DISABLED === - -Disable POSIX Termios Support ------------------------------ -.. index:: CONFIGURE_TERMIOS_DISABLED - -*CONSTANT:* - ``CONFIGURE_TERMIOS_DISABLED`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default, and resources are reserved for the - termios functionality. - -**DESCRIPTION:** - -This configuration parameter is defined if the software implementing -POSIX termios functionality is not going to be used by this application. - -**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. - -.. COMMENT: === CONFIGURE_NUMBER_OF_TERMIOS_PORTS === - -Specify Maximum Termios Ports ------------------------------ -.. index:: CONFIGURE_NUMBER_OF_TERMIOS_PORTS - -*CONSTANT:* - ``CONFIGURE_NUMBER_OF_TERMIOS_PORTS`` - -*DATA TYPE:* - Unsigned integer. - -*RANGE:* - Zero or positive. - -*DEFAULT VALUE:* - The default value is 1, so a console port can be used. - -**DESCRIPTION:** - -This configuration parameter is set to the number of ports using the -termios functionality. Each concurrently active termios port requires -resources. - -**NOTES:** - -If the application will be using serial ports -including, but not limited to, the Console Device -(e.g. ``CONFIGURE_APPLICATION_NEEDS_CONSOLE_DRIVER``), then it is -highly likely that this configuration parameter should NOT be is defined. - -.. COMMENT: === File System Configuration Parameters === - -File System Configuration Parameters -==================================== - -This section defines File System related configuration parameters. - -.. COMMENT: === CONFIGURE_HAS_OWN_MOUNT_TABLE === - -Providing Application Specific Mount Table ------------------------------------------- -.. index:: CONFIGURE_HAS_OWN_MOUNT_TABLE - -*CONSTANT:* - ``CONFIGURE_HAS_OWN_MOUNT_TABLE`` - -*DATA TYPE:* - Undefined or an array of type ``rtems_filesystem_mount_table_t``. - -*RANGE:* - Undefined or an array of type ``rtems_filesystem_mount_table_t``. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -This configuration parameter is defined when the application -provides their own filesystem mount table. The mount table is an -array of ``rtems_filesystem_mount_table_t`` entries pointed -to by the global variable ``rtems_filesystem_mount_table``. -The number of entries in this table is in an integer variable named``rtems_filesystem_mount_table_t``. - -.. COMMENT: XXX - is the variable name for the count right? - -**NOTES:** - -None. - -.. COMMENT: XXX - Please provide an example - -.. COMMENT: === CONFIGURE_USE_DEVFS_AS_BASE_FILESYSTEM === - -Configure devFS as Root File System ------------------------------------ -.. index:: CONFIGURE_USE_DEVFS_AS_BASE_FILESYSTEM - -*CONSTANT:* - ``CONFIGURE_USE_DEVFS_AS_BASE_FILESYSTEM`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This 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. - -**DESCRIPTION:** - -This configuration parameter is defined if the application wishes to -use the device-only filesytem as the root file system. - -**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. - -.. COMMENT: === CONFIGURE_MAXIMUM_DEVICES === - -Specifying Maximum Devices for devFS ------------------------------------- -.. index:: CONFIGURE_MAXIMUM_DEVICES - -*CONSTANT:* - ``CONFIGURE_MAXIMUM_DEVICES`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Positive. - -*DEFAULT VALUE:* - If ``BSP_MAXIMUM_DEVICES`` is defined, then the - default value is ``BSP_MAXIMUM_DEVICES``, otherwise the default value is 4. - -**DESCRIPTION:** - -``CONFIGURE_MAXIMUM_DEVICES`` is defined to the number of -individual devices that may be registered in the device file system (devFS). - -**NOTES:** - -This option is specific to the device file system (devFS) and should not be -confused with the ``CONFIGURE_MAXIMUM_DRIVERS`` option. This parameter only -impacts the devFS and thus is only used by ``<rtems/confdefs.h>`` when``CONFIGURE_USE_DEVFS_AS_BASE_FILESYSTEM`` is specified. - -.. COMMENT: === CONFIGURE_APPLICATION_DISABLE_FILESYSTEM === - -Disable File System Support ---------------------------- -.. index:: CONFIGURE_APPLICATION_DISABLE_FILESYSTEM - -*CONSTANT:* - ``CONFIGURE_APPLICATION_DISABLE_FILESYSTEM`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This 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. - -**DESCRIPTION:** - -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 ``printf()``. - -**NOTES:** - -None. - -.. COMMENT: === CONFIGURE_USE_MINIIMFS_AS_BASE_FILESYSTEM === - -Use a Root IMFS with a Minimalistic Feature Set ------------------------------------------------ -.. index:: CONFIGURE_USE_MINIIMFS_AS_BASE_FILESYSTEM - -*CONSTANT:* - ``CONFIGURE_USE_MINIIMFS_AS_BASE_FILESYSTEM`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -In case this configuration option is defined, then the following configuration -options will be defined as well - -- ``CONFIGURE_IMFS_DISABLE_CHMOD``, - -- ``CONFIGURE_IMFS_DISABLE_CHOWN``, - -- ``CONFIGURE_IMFS_DISABLE_UTIME``, - -- ``CONFIGURE_IMFS_DISABLE_LINK``, - -- ``CONFIGURE_IMFS_DISABLE_SYMLINK``, - -- ``CONFIGURE_IMFS_DISABLE_READLINK``, - -- ``CONFIGURE_IMFS_DISABLE_RENAME``, and - -- ``CONFIGURE_IMFS_DISABLE_UNMOUNT``. - -.. COMMENT: === CONFIGURE_IMFS_MEMFILE_BYTES_PER_BLOCK === - -Specify Block Size for IMFS ---------------------------- -.. index:: CONFIGURE_IMFS_MEMFILE_BYTES_PER_BLOCK - -*CONSTANT:* - ``CONFIGURE_IMFS_MEMFILE_BYTES_PER_BLOCK`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Valid values for this configuration parameter are a power of two (2) - between 16 and 512 inclusive. In other words, valid values are 16, - 32, 64, 128, 256,and 512. - -*DEFAULT VALUE:* - The default IMFS block size is 128 bytes. - -**DESCRIPTION:** - -This configuration parameter specifies the block size for in-memory files -managed by the IMFS. The configured block size has two impacts. The first -is the average amount of unused memory in the last block of each file. For -example, when the block size is 512, on average one-half of the last block -of each file will remain unused and the memory is wasted. In contrast, -when the block size is 16, the average unused memory per file is only -8 bytes. However, it requires more allocations for the same size file -and thus more overhead per block for the dynamic memory management. - -Second, the block size has an impact on the maximum size file that can -be stored in the IMFS. With smaller block size, the maximum file size -is correspondingly smaller. The following shows the maximum file size -possible based on the configured block size: - -- when the block size is 16 bytes, the maximum file size is 1,328 - bytes. - -- when the block size is 32 bytes, the maximum file size is 18,656 - bytes. - -- when the block size is 64 bytes, the maximum file size is 279,488 - bytes. - -- when the block size is 128 bytes, the maximum file size is - 4,329,344 bytes. - -- when the block size is 256 bytes, the maximum file size is - 68,173,568 bytes. - -- when the block size is 512 bytes, the maximum file size is - 1,082,195,456 bytes. - -.. COMMENT: === CONFIGURE_IMFS_DISABLE_CHOWN === - -Disable Change Owner Support of Root IMFS ------------------------------------------ -.. index:: CONFIGURE_IMFS_DISABLE_CHOWN - -*CONSTANT:* - ``CONFIGURE_IMFS_DISABLE_CHOWN`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -In case this configuration option is defined, then the support to change the -owner is disabled in the root IMFS. - -.. COMMENT: === CONFIGURE_IMFS_DISABLE_CHMOD === - -Disable Change Mode Support of Root IMFS ----------------------------------------- -.. index:: CONFIGURE_IMFS_DISABLE_CHMOD - -*CONSTANT:* - ``CONFIGURE_IMFS_DISABLE_CHMOD`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -In case this configuration option is defined, then the support to change the -mode is disabled in the root IMFS. - -.. COMMENT: === CONFIGURE_IMFS_DISABLE_UTIME === - -Disable Change Times Support of Root IMFS ------------------------------------------ -.. index:: CONFIGURE_IMFS_DISABLE_UTIME - -*CONSTANT:* - ``CONFIGURE_IMFS_DISABLE_UTIME`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -In case this configuration option is defined, then the support to change times -is disabled in the root IMFS. - -.. COMMENT: === CONFIGURE_IMFS_DISABLE_LINK === - -Disable Create Hard Link Support of Root IMFS ---------------------------------------------- -.. index:: CONFIGURE_IMFS_DISABLE_LINK - -*CONSTANT:* - ``CONFIGURE_IMFS_DISABLE_LINK`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -In case this configuration option is defined, then the support to create hard -links is disabled in the root IMFS. - -.. COMMENT: === CONFIGURE_IMFS_DISABLE_SYMLINK === - -Disable Create Symbolic Link Support of Root IMFS -------------------------------------------------- -.. index:: CONFIGURE_IMFS_DISABLE_SYMLINK - -*CONSTANT:* - ``CONFIGURE_IMFS_DISABLE_SYMLINK`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -In case this configuration option is defined, then the support to create -symbolic links is disabled in the root IMFS. - -.. COMMENT: === CONFIGURE_IMFS_DISABLE_READLINK === - -Disable Read Symbolic Link Support of Root IMFS ------------------------------------------------ -.. index:: CONFIGURE_IMFS_DISABLE_READLINK - -*CONSTANT:* - ``CONFIGURE_IMFS_DISABLE_READLINK`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -In case this configuration option is defined, then the support to read symbolic -links is disabled in the root IMFS. - -.. COMMENT: === CONFIGURE_IMFS_DISABLE_RENAME === - -Disable Rename Support of Root IMFS ------------------------------------ -.. index:: CONFIGURE_IMFS_DISABLE_RENAME - -*CONSTANT:* - ``CONFIGURE_IMFS_DISABLE_RENAME`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -In case this configuration option is defined, then the support to rename nodes -is disabled in the root IMFS. - -.. COMMENT: === CONFIGURE_IMFS_DISABLE_READDIR === - -Disable Directory Read Support of Root IMFS -------------------------------------------- -.. index:: CONFIGURE_IMFS_DISABLE_READDIR - -*CONSTANT:* - ``CONFIGURE_IMFS_DISABLE_READDIR`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -In case this configuration option is defined, then the support to read a -directory is disabled in the root IMFS. It is still possible to open nodes in -a directory. - -.. COMMENT: === CONFIGURE_IMFS_DISABLE_MOUNT === - -Disable Mount Support of Root IMFS ----------------------------------- -.. index:: CONFIGURE_IMFS_DISABLE_MOUNT - -*CONSTANT:* - ``CONFIGURE_IMFS_DISABLE_MOUNT`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -In case this configuration option is defined, then the support to mount other -file systems is disabled in the root IMFS. - -.. COMMENT: === CONFIGURE_IMFS_DISABLE_UNMOUNT === - -Disable Unmount Support of Root IMFS ------------------------------------- -.. index:: CONFIGURE_IMFS_DISABLE_UNMOUNT - -*CONSTANT:* - ``CONFIGURE_IMFS_DISABLE_UNMOUNT`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -In case this configuration option is defined, then the support to unmount file -systems is disabled in the root IMFS. - -.. COMMENT: === CONFIGURE_IMFS_DISABLE_MKNOD === - -Disable Make Nodes Support of Root IMFS ---------------------------------------- -.. index:: CONFIGURE_IMFS_DISABLE_MKNOD - -*CONSTANT:* - ``CONFIGURE_IMFS_DISABLE_MKNOD`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -In case this configuration option is defined, then the support to make -directories, devices, regular files and FIFOs is disabled in the root IMFS. - -.. COMMENT: === CONFIGURE_IMFS_DISABLE_MKNOD_FILE === - -Disable Make Files Support of Root IMFS ---------------------------------------- -.. index:: CONFIGURE_IMFS_DISABLE_MKNOD_FILE - -*CONSTANT:* - ``CONFIGURE_IMFS_DISABLE_MKNOD_FILE`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -In case this configuration option is defined, then the support to make regular -files is disabled in the root IMFS. - -.. COMMENT: === CONFIGURE_IMFS_DISABLE_RMNOD === - -Disable Remove Nodes Support of Root IMFS ------------------------------------------ -.. index:: CONFIGURE_IMFS_DISABLE_RMNOD - -*CONSTANT:* - ``CONFIGURE_IMFS_DISABLE_RMNOD`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -In case this configuration option is defined, then the support to remove nodes -is disabled in the root IMFS. - -.. COMMENT: === Block Device Cache Configuration === - -Block Device Cache Configuration -================================ - -This section defines Block Device Cache (bdbuf) related configuration -parameters. - -.. COMMENT: === CONFIGURE_APPLICATION_NEEDS_LIBBLOCK === - -Enable Block Device Cache -------------------------- -.. index:: CONFIGURE_APPLICATION_NEEDS_LIBBLOCK - -*CONSTANT:* - ``CONFIGURE_APPLICATION_NEEDS_LIBBLOCK`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -Provides a Block Device Cache configuration. - -**NOTES:** - -Each option of the Block Device Cache configuration can be explicitly set by -the user with the configuration options below. The Block Device Cache is used -for example by the RFS and DOSFS file systems. - -.. COMMENT: === CONFIGURE_BDBUF_CACHE_MEMORY_SIZE === - -Size of the Cache Memory ------------------------- -.. index:: CONFIGURE_BDBUF_CACHE_MEMORY_SIZE - -*CONSTANT:* - ``CONFIGURE_BDBUF_CACHE_MEMORY_SIZE`` - -*DATA TYPE:* - Unsigned integer (``size_t``). - -*RANGE:* - Positive. - -*DEFAULT VALUE:* - The default value is 32768 bytes. - -**DESCRIPTION:** - -Size of the cache memory in bytes. - -**NOTES:** - -None. - -.. COMMENT: === CONFIGURE_BDBUF_BUFFER_MIN_SIZE === - -Minimum Size of a Buffer ------------------------- -.. index:: CONFIGURE_BDBUF_BUFFER_MIN_SIZE - -*CONSTANT:* - ``CONFIGURE_BDBUF_BUFFER_MIN_SIZE`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Positive. - -*DEFAULT VALUE:* - The default value is 512 bytes. - -**DESCRIPTION:** - -Defines the minimum size of a buffer in bytes. - -**NOTES:** - -None. - -.. COMMENT: === CONFIGURE_BDBUF_BUFFER_MAX_SIZE === - -Maximum Size of a Buffer ------------------------- -.. index:: CONFIGURE_BDBUF_BUFFER_MAX_SIZE - -*CONSTANT:* - ``CONFIGURE_BDBUF_BUFFER_MAX_SIZE`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - It must be positive and an integral multiple of the buffer minimum size. - -*DEFAULT VALUE:* - The default value is 4096 bytes. - -**DESCRIPTION:** - -Defines the maximum size of a buffer in bytes. - -**NOTES:** - -None. - -.. COMMENT: === CONFIGURE_SWAPOUT_SWAP_PERIOD === - -Swapout Task Swap Period ------------------------- -.. index:: CONFIGURE_SWAPOUT_SWAP_PERIOD - -*CONSTANT:* - ``CONFIGURE_SWAPOUT_SWAP_PERIOD`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Positive. - -*DEFAULT VALUE:* - The default value is 250 milliseconds. - -**DESCRIPTION:** - -Defines the swapout task swap period in milliseconds. - -**NOTES:** - -None. - -.. COMMENT: === CONFIGURE_SWAPOUT_BLOCK_HOLD === - -Swapout Task Maximum Block Hold Time ------------------------------------- -.. index:: CONFIGURE_SWAPOUT_BLOCK_HOLD - -*CONSTANT:* - ``CONFIGURE_SWAPOUT_BLOCK_HOLD`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Positive. - -*DEFAULT VALUE:* - The default value is 1000 milliseconds. - -**DESCRIPTION:** - -Defines the swapout task maximum block hold time in milliseconds. - -**NOTES:** - -None. - -.. COMMENT: === CONFIGURE_SWAPOUT_TASK_PRIORITY === - -Swapout Task Priority ---------------------- -.. index:: CONFIGURE_SWAPOUT_TASK_PRIORITY - -*CONSTANT:* - ``CONFIGURE_SWAPOUT_TASK_PRIORITY`` - -*DATA TYPE:* - Task priority (``rtems_task_priority``). - -*RANGE:* - Valid task priority. - -*DEFAULT VALUE:* - The default value is 15. - -**DESCRIPTION:** - -Defines the swapout task priority. - -**NOTES:** - -None. - -.. COMMENT: === CONFIGURE_BDBUF_MAX_READ_AHEAD_BLOCKS === - -Maximum Blocks per Read-Ahead Request -------------------------------------- -.. index:: CONFIGURE_BDBUF_MAX_READ_AHEAD_BLOCKS - -*CONSTANT:* - ``CONFIGURE_BDBUF_MAX_READ_AHEAD_BLOCKS`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Positive. - -*DEFAULT VALUE:* - The default value is 0. - -**DESCRIPTION:** - -Defines the maximum blocks per read-ahead request. - -**NOTES:** - -A value of 0 disables the read-ahead task (default). The read-ahead task will -issue speculative read transfers if a sequential access pattern is detected. -This can improve the performance on some systems. - -.. COMMENT: === CONFIGURE_BDBUF_MAX_WRITE_BLOCKS === - -Maximum Blocks per Write Request --------------------------------- -.. index:: CONFIGURE_BDBUF_MAX_WRITE_BLOCKS - -*CONSTANT:* - ``CONFIGURE_BDBUF_MAX_WRITE_BLOCKS`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Positive. - -*DEFAULT VALUE:* - The default value is 16. - -**DESCRIPTION:** - -Defines the maximum blocks per write request. - -**NOTES:** - -None. - -.. COMMENT: === CONFIGURE_BDBUF_TASK_STACK_SIZE === - -Task Stack Size of the Block Device Cache Tasks ------------------------------------------------ -.. index:: CONFIGURE_BDBUF_TASK_STACK_SIZE - -*CONSTANT:* - ``CONFIGURE_BDBUF_TASK_STACK_SIZE`` - -*DATA TYPE:* - Unsigned integer (``size_t``). - -*RANGE:* - Zero or positive. - -*DEFAULT VALUE:* - The default value is RTEMS_MINIMUM_STACK_SIZE. - -**DESCRIPTION:** - -Defines the task stack size of the Block Device Cache tasks in bytes. - -**NOTES:** - -None. - -.. COMMENT: === CONFIGURE_BDBUF_READ_AHEAD_TASK_PRIORITY === - -Read-Ahead Task Priority ------------------------- -.. index:: CONFIGURE_BDBUF_READ_AHEAD_TASK_PRIORITY - -*CONSTANT:* - ``CONFIGURE_BDBUF_READ_AHEAD_TASK_PRIORITY`` - -*DATA TYPE:* - Task priority (``rtems_task_priority``). - -*RANGE:* - Valid task priority. - -*DEFAULT VALUE:* - The default value is 15. - -**DESCRIPTION:** - -Defines the read-ahead task priority. - -**NOTES:** - -None. - -.. COMMENT: === CONFIGURE_SWAPOUT_WORKER_TASKS === - -Swapout Worker Task Count -------------------------- -.. index:: CONFIGURE_SWAPOUT_WORKER_TASKS - -*CONSTANT:* - ``CONFIGURE_SWAPOUT_WORKER_TASKS`` - -*DATA TYPE:* - Unsigned integer (``size_t``). - -*RANGE:* - Zero or positive. - -*DEFAULT VALUE:* - The default value is 0. - -**DESCRIPTION:** - -Defines the swapout worker task count. - -**NOTES:** - -None. - -.. COMMENT: === CONFIGURE_SWAPOUT_WORKER_TASK_PRIORITY === - -Swapout Worker Task Priority ----------------------------- -.. index:: CONFIGURE_SWAPOUT_WORKER_TASK_PRIORITY - -*CONSTANT:* - ``CONFIGURE_SWAPOUT_WORKER_TASK_PRIORITY`` - -*DATA TYPE:* - Task priority (``rtems_task_priority``). - -*RANGE:* - Valid task priority. - -*DEFAULT VALUE:* - The default value is 15. - -**DESCRIPTION:** - -Defines the swapout worker task priority. - -**NOTES:** - -None. - -.. COMMENT: === BSP Specific Settings === - -BSP Specific Settings -===================== - -This section describes BSP specific configuration settings used by``<rtems/confdefs.h>``. The BSP specific configuration settings are -defined in ``<bsp.h>``. - -.. COMMENT: === Disable BSP Settings === - -Disable BSP Configuration Settings ----------------------------------- -.. index:: CONFIGURE_DISABLE_BSP_SETTINGS - -*CONSTANT:* - ``CONFIGURE_DISABLE_BSP_SETTINGS`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -All BSP specific configuration settings can be disabled by the application -with the ``CONFIGURE_DISABLE_BSP_SETTINGS`` option. - -**NOTES:** - -None. - -.. COMMENT: === CONFIGURE_MALLOC_BSP_SUPPORTS_SBRK === - -Specify BSP Supports sbrk() ---------------------------- -.. index:: CONFIGURE_MALLOC_BSP_SUPPORTS_SBRK - -*CONSTANT:* - ``CONFIGURE_MALLOC_BSP_SUPPORTS_SBRK`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This option is BSP specific. - -**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 ``malloc()`` is unable to allocate memory, it will -call the BSP supplied ``sbrk()`` to obtain more memory. - -**NOTES:** - -This parameter should not be defined by the application. Only the BSP -knows how it allocates memory to the C Program Heap. - -.. COMMENT: === BSP_IDLE_TASK_BODY === - -Specify BSP Specific Idle Task ------------------------------- -.. index:: BSP_IDLE_TASK_BODY - -*CONSTANT:* - ``BSP_IDLE_TASK_BODY`` - -*DATA TYPE:* - Function pointer. - -*RANGE:* - Undefined or valid function pointer. - -*DEFAULT VALUE:* - This option is BSP specific. - -**DESCRIPTION:** - -If ``BSP_IDLE_TASK_BODY`` is defined by the BSP and``CONFIGURE_IDLE_TASK_BODY`` is not defined by the application, -then this BSP specific idle task body will be used. - -**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 - -.. COMMENT: === BSP_IDLE_TASK_STACK_SIZE === - -Specify BSP Suggested Value for IDLE Task Stack Size ----------------------------------------------------- -.. index:: BSP_IDLE_TASK_STACK_SIZE - -*CONSTANT:* - ``BSP_IDLE_TASK_STACK_SIZE`` - -*DATA TYPE:* - Unsigned integer (``size_t``). - -*RANGE:* - Undefined or positive. - -*DEFAULT VALUE:* - This option is BSP specific. - -**DESCRIPTION:** - -If ``BSP_IDLE_TASK_STACK_SIZE`` is defined by the BSP and``CONFIGURE_IDLE_TASK_STACK_SIZE`` is not defined by the application, -then this BSP suggested idle task stack size will be used. - -**NOTES:** - -The order of precedence for configuring the IDLE task stack size is: - -- RTEMS default minimum stack size. - -- If defined, then ``CONFIGURE_MINIMUM_TASK_STACK_SIZE``. - -- If defined, then the BSP specific ``BSP_IDLE_TASK_SIZE``. - -- If defined, then the application specified``CONFIGURE_IDLE_TASK_SIZE``. - -.. COMMENT: XXX - add cross references to other related values. - -.. COMMENT: === BSP_INITIAL_EXTENSION === - -Specify BSP Specific User Extensions ------------------------------------- -.. index:: BSP_INITIAL_EXTENSION - -*CONSTANT:* - ``BSP_INITIAL_EXTENSION`` - -*DATA TYPE:* - List of user extension initializers (``rtems_extensions_table``). - -*RANGE:* - Undefined or a list of user extension initializers. - -*DEFAULT VALUE:* - This option is BSP specific. - -**DESCRIPTION:** - -If ``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. - -**NOTES:** - -None. - -.. COMMENT: === BSP_INTERRUPT_STACK_SIZE === - -Specifying BSP Specific Interrupt Stack Size --------------------------------------------- -.. index:: BSP_INTERRUPT_STACK_SIZE - -*CONSTANT:* - ``BSP_INTERRUPT_STACK_SIZE`` - -*DATA TYPE:* - Unsigned integer (``size_t``). - -*RANGE:* - Undefined or positive. - -*DEFAULT VALUE:* - This option is BSP specific. - -**DESCRIPTION:** - -If ``BSP_INTERRUPT_STACK_SIZE`` is defined by the BSP and``CONFIGURE_INTERRUPT_STACK_SIZE`` is not defined by the application, -then this BSP specific interrupt stack size will be used. - -**NOTES:** - -None. - -.. COMMENT: === BSP_MAXIMUM_DEVICES === - -Specifying BSP Specific Maximum Devices ---------------------------------------- -.. index:: BSP_MAXIMUM_DEVICES - -*CONSTANT:* - ``BSP_MAXIMUM_DEVICES`` - -*DATA TYPE:* - Unsigned integer (``size_t``). - -*RANGE:* - Undefined or positive. - -*DEFAULT VALUE:* - This option is BSP specific. - -**DESCRIPTION:** - -If ``BSP_MAXIMUM_DEVICES`` is defined by the BSP and``CONFIGURE_MAXIMUM_DEVICES`` is not defined by the application, -then this BSP specific maximum device count will be used. - -**NOTES:** - -This option is specific to the device file system (devFS) and should not be -confused with the ``CONFIGURE_MAXIMUM_DRIVERS`` option. This parameter only -impacts the devFS and thus is only used by ``<rtems/confdefs.h>`` when``CONFIGURE_USE_DEVFS_AS_BASE_FILESYSTEM`` is specified. - -.. COMMENT: === BSP_ZERO_WORKSPACE_AUTOMATICALLY === - -BSP Recommends RTEMS Workspace be Cleared ------------------------------------------ -.. index:: BSP_ZERO_WORKSPACE_AUTOMATICALLY - -*CONSTANT:* - ``BSP_ZERO_WORKSPACE_AUTOMATICALLY`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This option is BSP specific. - -**DESCRIPTION:** - -If ``BSP_ZERO_WORKSPACE_AUTOMATICALLY`` is defined by the BSP and``CONFIGURE_ZERO_WORKSPACE_AUTOMATICALLY`` is not defined by the -application, then the workspace will be zeroed automatically. - -**NOTES:** - -Zeroing memory can add significantly to system boot time. It is not -necessary for RTEMS but is often assumed by support libraries. - -.. COMMENT: === CONFIGURE_BSP_PREREQUISITE_DRIVERS === - -Specify BSP Prerequisite Drivers --------------------------------- -.. index:: CONFIGURE_BSP_PREREQUISITE_DRIVERS - -*CONSTANT:* - ``CONFIGURE_BSP_PREREQUISITE_DRIVERS`` - -*DATA TYPE:* - List of device driver initializers (``rtems_driver_address_table``). - -*RANGE:* - Undefined or array of device drivers. - -*DEFAULT VALUE:* - This option is BSP specific. - -**DESCRIPTION:** - -``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 *FRONT* of the Device Driver Table and initialized before -any other drivers *INCLUDING* any application prerequisite drivers. - -**NOTES:** - -``CONFIGURE_BSP_PREREQUISITE_DRIVERS`` is typically used by BSPs -to configure common infrastructure such as bus controllers or probe -for devices. - -.. COMMENT: === Idle Task Configuration === - -Idle Task Configuration -======================= - -This section defines the IDLE task related configuration parameters -supported by ``<rtems/confdefs.h>``. - -.. COMMENT: === CONFIGURE_IDLE_TASK_BODY === - -Specify Application Specific Idle Task Body -------------------------------------------- -.. index:: CONFIGURE_IDLE_TASK_BODY - -*CONSTANT:* - ``CONFIGURE_IDLE_TASK_BODY`` - -*DATA TYPE:* - Function pointer. - -*RANGE:* - Undefined or valid function pointer. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -``CONFIGURE_IDLE_TASK_BODY`` is set to the function name corresponding -to the application specific IDLE thread body. If not specified, the -BSP or RTEMS default IDLE thread body will be used. - -**NOTES:** - -None. - -.. COMMENT: === CONFIGURE_IDLE_TASK_STACK_SIZE === - -Specify Idle Task Stack Size ----------------------------- -.. index:: CONFIGURE_IDLE_TASK_STACK_SIZE - -*CONSTANT:* - ``CONFIGURE_IDLE_TASK_STACK_SIZE`` - -*DATA TYPE:* - Unsigned integer (``size_t``). - -*RANGE:* - Undefined or positive. - -*DEFAULT VALUE:* - The default value is RTEMS_MINIMUM_STACK_SIZE. - -**DESCRIPTION:** - -``CONFIGURE_IDLE_TASK_STACK_SIZE`` is set to the -desired stack size for the IDLE task. - -**NOTES:** - -None. - -.. COMMENT: === CONFIGURE_IDLE_TASK_INITIALIZES_APPLICATION === - -Specify Idle Task Performs Application Initialization ------------------------------------------------------ -.. index:: CONFIGURE_IDLE_TASK_INITIALIZES_APPLICATION - -*CONSTANT:* - ``CONFIGURE_IDLE_TASK_INITIALIZES_APPLICATION`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default, the user is assumed - to provide one or more initialization tasks. - -**DESCRIPTION:** - -``CONFIGURE_IDLE_TASK_INITIALIZES_APPLICATION`` is set to -indicate that the user has configured *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. - -**NOTES:** - -If you use this option be careful, the user IDLE task *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. - -.. COMMENT: === Scheduler Algorithm Configuration === - -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: - -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. - -.. COMMENT: === CONFIGURE_SCHEDULER_PRIORITY === - -Use Deterministic Priority Scheduler ------------------------------------- -.. index:: CONFIGURE_SCHEDULER_PRIORITY - -*CONSTANT:* - ``CONFIGURE_SCHEDULER_PRIORITY`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is defined by default. - This is the default scheduler and specifying this - configuration parameter is redundant. - -**DESCRIPTION:** - -The Deterministic Priority Scheduler is the default scheduler in RTEMS -for uni-processor 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. - -**NOTES:** - -This scheduler may be explicitly selected by defining``CONFIGURE_SCHEDULER_PRIORITY`` although this is equivalent to the -default behavior. - -.. COMMENT: === CONFIGURE_SCHEDULER_SIMPLE === - -Use Simple Priority Scheduler ------------------------------ -.. index:: CONFIGURE_SCHEDULER_SIMPLE - -*CONSTANT:* - ``CONFIGURE_SCHEDULER_SIMPLE`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**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``CONFIGURE_SCHEDULER_SIMPLE``. - -**NOTES:** - -This scheduler is appropriate for use in small systems where RAM is limited. - -.. COMMENT: === CONFIGURE_SCHEDULER_EDF === - -Use Earliest Deadline First Scheduler -------------------------------------- -.. index:: CONFIGURE_SCHEDULER_EDF - -*CONSTANT:* - ``CONFIGURE_SCHEDULER_EDF`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -The Earliest Deadline First Scheduler (EDF) is an alternative scheduler in -RTEMS for uni-processor 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``CONFIGURE_SCHEDULER_EDF``. - -**NOTES:** - -None. - -.. COMMENT: === CONFIGURE_SCHEDULER_CBS === - -Use Constant Bandwidth Server Scheduler ---------------------------------------- -.. index:: CONFIGURE_SCHEDULER_CBS - -*CONSTANT:* - ``CONFIGURE_SCHEDULER_CBS`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -The Constant Bandwidth Server Scheduler (CBS) is an alternative scheduler -in RTEMS for uni-processor 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``CONFIGURE_SCHEDULER_CBS``. - -.. COMMENT: XXX - add cross reference to API chapter - -**NOTES:** - -None. - -.. COMMENT: === CONFIGURE_SCHEDULER_PRIORITY_SMP === - -Use Deterministic Priority SMP Scheduler ----------------------------------------- -.. index:: CONFIGURE_SCHEDULER_PRIORITY_SMP - -*CONSTANT:* - ``CONFIGURE_SCHEDULER_PRIORITY_SMP`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -The Deterministic Priority SMP Scheduler is derived from the Deterministic -Priority Scheduler but is capable of scheduling threads across multiple -processors. - -In a configuration with SMP enabled at configure time, it may be -explicitly selected by defining ``CONFIGURE_SCHEDULER_PRIORITY_SMP``. - -**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 ``CONFIGURE_SMP_APPLICATION`` is defined. - -.. COMMENT: === CONFIGURE_SCHEDULER_SIMPLE_SMP === - -Use Simple SMP Priority Scheduler ---------------------------------- -.. index:: CONFIGURE_SCHEDULER_SIMPLE_SMP - -*CONSTANT:* - ``CONFIGURE_SCHEDULER_SIMPLE_SMP`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -The Simple SMP Priority Scheduler is derived from the Simple Priority -Scheduler but is capable of scheduling threads across multiple processors. -It is designed to provide the same task scheduling behaviour as the -Deterministic Priority Scheduler while distributing threads across -multiple processors. 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 processors, 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 ``CONFIGURE_SCHEDULER_SIMPLE_SMP``. - -**NOTES:** - -This scheduler is only available when RTEMS is configured with SMP -support enabled. - -.. COMMENT: === Configuring a Scheduler Name === - -Configuring a Scheduler Name ----------------------------- -.. index:: CONFIGURE_SCHEDULER_NAME - -*CONSTANT:* - ``CONFIGURE_SCHEDULER_NAME`` - -*DATA TYPE:* - RTEMS Name (``rtems_name``). - -*RANGE:* - Any value. - -*DEFAULT VALUE:* - The default name is - - ``"UCBS"`` for the Uni-Processor CBS scheduler, - - ``"UEDF"`` for the Uni-Processor EDF scheduler, - - ``"UPD "`` for the Uni-Processor Deterministic Priority scheduler, - - ``"UPS "`` for the Uni-Processor Simple Priority scheduler, - - ``"MPA "`` for the Multi-Processor Priority Affinity scheduler, and - - ``"MPD "`` for the Multi-Processor Deterministic Priority scheduler, and - - ``"MPS "`` for the Multi-Processor Simple Priority scheduler. - -**DESCRIPTION:** - -Schedulers can be identified via ``rtems_scheduler_ident``. The name of the scheduler is determined by the configuration. - -**NOTES:** - -None. - -.. COMMENT: === Configuring a User Scheduler === - -Configuring a User Provided Scheduler -------------------------------------- -.. index:: CONFIGURE_SCHEDULER_USER - -*CONSTANT:* - ``CONFIGURE_SCHEDULER_USER`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -RTEMS allows the application to provide its own task/thread -scheduling algorithm. In order to do this, one must define``CONFIGURE_SCHEDULER_USER`` to indicate the application provides its -own scheduling algorithm. If ``CONFIGURE_SCHEDULER_USER`` is defined -then the following additional macros must be defined: - -- ``CONFIGURE_SCHEDULER_CONTEXT`` must be defined to a static definition - of the scheduler context of the user scheduler. - -- ``CONFIGURE_SCHEDULER_CONTROLS`` must be defined to a scheduler - control initializer for the user scheduler. - -- ``CONFIGURE_SCHEDULER_USER_PER_THREAD`` must be defined to the type of - the per-thread information of the user scheduler. - -**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 ``cpukit/score/src/schedulerpriority*.c`` for -guidance. For guidance on the configuration macros, please examine``cpukit/sapi/include/confdefs.h`` for how these are defined for the -Deterministic Priority Scheduler. - -.. COMMENT: === Configuring Clustered Schedulers === - -Configuring Clustered Schedulers --------------------------------- - -Clustered scheduling helps to control the worst-case latencies in a -multi-processor system. The goal is to reduce the amount of shared state in -the system and thus prevention of lock contention. Modern multi-processor -systems tend to have several layers of data and instruction caches. With -clustered scheduling it is possible to honour the cache topology of a system -and thus avoid expensive cache synchronization traffic. - -We have clustered scheduling in case the set of processors of a system is -partitioned into non-empty pairwise-disjoint subsets. These subsets are called -clusters. Clusters with a cardinality of one are partitions. Each cluster is -owned by exactly one scheduler instance. In order to use clustered -scheduling the application designer has to answer two questions. - -# How is the set of processors partitioned into clusters? - -# Which scheduler is used for which cluster? - -**CONFIGURATION:** - -The schedulers in an SMP system are statically configured on RTEMS. Firstly -the application must select which scheduling algorithms are available with the -following defines - -- ``CONFIGURE_SCHEDULER_PRIORITY_SMP``, - -- ``CONFIGURE_SCHEDULER_SIMPLE_SMP``, and - -- ``CONFIGURE_SCHEDULER_PRIORITY_AFFINITY_SMP``. - -This is necessary to calculate the per-thread overhead introduced by the -schedulers. After these definitions the configuration file must ``#include -<rtems/scheduler.h>`` to have access to scheduler specific configuration macros. -Each scheduler needs a context to store state information at run-time. To -provide a context for each scheduler is the next step. Use the following -macros to create scheduler contexts - -- ``RTEMS_SCHEDULER_CONTEXT_PRIORITY_SMP(name, prio_count)``, - -- ``RTEMS_SCHEDULER_CONTEXT_SIMPLE_SMP(name)``, and - -- ``RTEMS_SCHEDULER_CONTEXT_PRIORITY_AFFINITY_SMP(name, prio_count)``. - -The ``name`` parameter is used as part of a designator for a global -variable, so the usual C/C++ designator rules apply. Additional parameters are -scheduler specific. The schedulers are registered in the system via the -scheduler table. To create the scheduler table define``CONFIGURE_SCHEDULER_CONTROLS`` to a list of the following scheduler -control initializers - -- ``RTEMS_SCHEDULER_CONTROL_PRIORITY_SMP(name, obj_name)``, - -- ``RTEMS_SCHEDULER_CONTROL_SIMPLE_SMP(name, obj_name)``, and - -- ``RTEMS_SCHEDULER_CONTROL_PRIORITY_AFFINITY_SMP(name, obj_name)``. - -The ``name`` parameter must correspond to the parameter defining the -scheduler context. The ``obj_name`` determines the scheduler object name -and can be used in ``rtems_scheduler_ident()`` to get the scheduler object -identifier. - -The last step is to define which processor uses which scheduler. -For this purpose a scheduler assignment table must be defined. The entry count -of this table must be equal to the configured maximum processors -(``CONFIGURE_SMP_MAXIMUM_PROCESSORS``). A processor assignment to a -scheduler can be optional or mandatory. The boot processor must have a -scheduler assigned. In case the system needs more mandatory processors than -available then a fatal run-time error will occur. To specify the scheduler -assignments define ``CONFIGURE_SMP_SCHEDULER_ASSIGNMENTS`` to a list of``RTEMS_SCHEDULER_ASSIGN(index, attr)`` and``RTEMS_SCHEDULER_ASSIGN_NO_SCHEDULER`` macros. The ``index`` parameter -must be a valid index into the scheduler table. The ``attr`` parameter -defines the scheduler assignment attributes. By default a scheduler assignment -to a processor is optional. For the scheduler assignment attribute use one of -the mutually exclusive variants - -- ``RTEMS_SCHEDULER_ASSIGN_DEFAULT``, - -- ``RTEMS_SCHEDULER_ASSIGN_PROCESSOR_MANDATORY``, and - -- ``RTEMS_SCHEDULER_ASSIGN_PROCESSOR_OPTIONAL``. - -**ERRORS:** - -In case one of the scheduler indices in``CONFIGURE_SMP_SCHEDULER_ASSIGNMENTS`` is invalid a link-time error will -occur with an undefined reference to ``RTEMS_SCHEDULER_INVALID_INDEX``. - -Some fatal errors may occur in case of scheduler configuration inconsistencies or a lack -of processors on the system. The fatal source is``RTEMS_FATAL_SOURCE_SMP``. None of the errors is internal. - -- ``SMP_FATAL_BOOT_PROCESSOR_NOT_ASSIGNED_TO_SCHEDULER`` - the boot - processor must have a scheduler assigned. - -- ``SMP_FATAL_MANDATORY_PROCESSOR_NOT_PRESENT`` - there exists a - mandatory processor beyond the range of physically or virtually available - processors. The processor demand must be reduced for this system. - -- ``SMP_FATAL_START_OF_MANDATORY_PROCESSOR_FAILED`` - the start of a - mandatory processor failed during system initialization. The system may not - have this processor at all or it could be a problem with a boot loader for - example. Check the ``CONFIGURE_SMP_SCHEDULER_ASSIGNMENTS`` definition. - -- ``SMP_FATAL_MULTITASKING_START_ON_UNASSIGNED_PROCESSOR`` - it is not - allowed to start multitasking on a processor with no scheduler assigned. - -**EXAMPLE:** - -The following example shows a scheduler configuration for a hypothetical -product using two chip variants. One variant has four processors which is used -for the normal product line and another provides eight processors for the -high-performance product line. The first processor performs hard-real time -control of actuators and sensors. The second processor is not used by RTEMS at -all and runs a Linux instance to provide a graphical user interface. The -additional processors are used for a worker thread pool to perform data -processing operations. - -The processors managed by RTEMS use two Deterministic Priority scheduler -instances capable of dealing with 256 priority levels. The scheduler with -index zero has the name ``"IO "``. The scheduler with index one has the -name ``"WORK"``. The scheduler assignments of the first, third and fourth -processor are mandatory, so the system must have at least four processors, -otherwise a fatal run-time error will occur during system startup. The -processor assignments for the fifth up to the eighth processor are optional so -that the same application can be used for the normal and high-performance -product lines. The second processor has no scheduler assigned and runs Linux. -A hypervisor will ensure that the two systems cannot interfere in an -undesirable way. -.. code:: c - - #define CONFIGURE_SMP_MAXIMUM_PROCESSORS 8 - #define CONFIGURE_MAXIMUM_PRIORITY 255 - /* Make the scheduler algorithm available \*/ - #define CONFIGURE_SCHEDULER_PRIORITY_SMP - #include <rtems/scheduler.h> - /* Create contexts for the two scheduler instances \*/ - RTEMS_SCHEDULER_CONTEXT_PRIORITY_SMP(io, CONFIGURE_MAXIMUM_PRIORITY + 1); - RTEMS_SCHEDULER_CONTEXT_PRIORITY_SMP(work, CONFIGURE_MAXIMUM_PRIORITY + 1); - /* Define the scheduler table \*/ - #define CONFIGURE_SCHEDULER_CONTROLS \\ - RTEMS_SCHEDULER_CONTROL_PRIORITY_SMP( \\ - io, \\ - rtems_build_name('I', 'O', ' ', ' ') \\ - ), \\ - RTEMS_SCHEDULER_CONTROL_PRIORITY_SMP( \\ - work, \\ - rtems_build_name('W', 'O', 'R', 'K') \\ - ) - /* Define the processor to scheduler assignments \*/ - #define CONFIGURE_SMP_SCHEDULER_ASSIGNMENTS \\ - RTEMS_SCHEDULER_ASSIGN(0, RTEMS_SCHEDULER_ASSIGN_PROCESSOR_MANDATORY), \\ - RTEMS_SCHEDULER_ASSIGN_NO_SCHEDULER, \\ - RTEMS_SCHEDULER_ASSIGN(1, RTEMS_SCHEDULER_ASSIGN_PROCESSOR_MANDATORY), \\ - RTEMS_SCHEDULER_ASSIGN(1, RTEMS_SCHEDULER_ASSIGN_PROCESSOR_MANDATORY), \\ - RTEMS_SCHEDULER_ASSIGN(1, RTEMS_SCHEDULER_ASSIGN_PROCESSOR_OPTIONAL), \\ - RTEMS_SCHEDULER_ASSIGN(1, RTEMS_SCHEDULER_ASSIGN_PROCESSOR_OPTIONAL), \\ - RTEMS_SCHEDULER_ASSIGN(1, RTEMS_SCHEDULER_ASSIGN_PROCESSOR_OPTIONAL), \\ - RTEMS_SCHEDULER_ASSIGN(1, RTEMS_SCHEDULER_ASSIGN_PROCESSOR_OPTIONAL) - -.. COMMENT: === SMP Specific Configuration Parameters === - -SMP Specific Configuration Parameters -===================================== - -When RTEMS is configured to support SMP target systems, there are other -configuration parameters which apply. - -.. COMMENT: XXX - add -enable-smp - -.. COMMENT: === CONFIGURE_SMP_APPLICATION === - - -Enable SMP Support for Applications ------------------------------------ -.. index:: CONFIGURE_SMP_APPLICATION - -*CONSTANT:* - ``CONFIGURE_SMP_APPLICATION`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -``CONFIGURE_SMP_APPLICATION`` must be defined to enable SMP support for the -application. - -**NOTES:** - -This define may go away in the future in case all RTEMS components are SMP -ready. This configuration define is ignored on uni-processor configurations. - -.. COMMENT: === CONFIGURE_SMP_MAXIMUM_PROCESSORS === - -Specify Maximum Processors in SMP System ----------------------------------------- -.. index:: CONFIGURE_SMP_MAXIMUM_PROCESSORS - -*CONSTANT:* - ``CONFIGURE_SMP_MAXIMUM_PROCESSORS`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - The default value is 1, (if CONFIGURE_SMP_APPLICATION is defined). - -**DESCRIPTION:** - -``CONFIGURE_SMP_MAXIMUM_PROCESSORS`` must be set to the number of -processors in the SMP configuration. - -**NOTES:** - -If there are more processors available than configured, the rest will be -ignored. This configuration define is ignored on uni-processor configurations. - -.. COMMENT: === Device Driver Table === - -Device Driver Table -=================== - -This section defines the configuration parameters related -to the automatic generation of a Device Driver Table. As``<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. - -Note that network device drivers are not configured in the Device Driver Table. - -.. COMMENT: === CONFIGURE_MAXIMUM_DRIVERS === - -Specifying the Maximum Number of Device Drivers ------------------------------------------------ -.. index:: CONFIGURE_MAXIMUM_DRIVERS - -*CONSTANT:* - ``CONFIGURE_MAXIMUM_DRIVERS`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Zero or positive. - -*DEFAULT VALUE:* - This is computed by default, and is set to the number of device drivers - configured using the ``CONFIGURE_APPLICATIONS_NEEDS_XXX_DRIVER`` - configuration parameters. - -**DESCRIPTION:** - -``CONFIGURE_MAXIMUM_DRIVERS`` is defined as the number of device -drivers per node. - -**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``CONFIGURE_APPLICATIONS_NEEDS_XXX_DRIVER`` configuration parameters -are statically installed. - -.. COMMENT: === CONFIGURE_APPLICATION_NEEDS_CONSOLE_DRIVER === - -Enable Console Device Driver ----------------------------- -.. index:: CONFIGURE_APPLICATION_NEEDS_CONSOLE_DRIVER - -*CONSTANT:* - ``CONFIGURE_APPLICATION_NEEDS_CONSOLE_DRIVER`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -``CONFIGURE_APPLICATION_NEEDS_CONSOLE_DRIVER`` is defined if the -application wishes to include the Console Device Driver. - -**NOTES:** - -This device driver is responsible for providing standard input and output -using */dev/console*. - -BSPs should be constructed in a manner that allows ``printk()`` -to work properly without the need for the console driver to be configured. - -.. COMMENT: === CONFIGURE_APPLICATION_NEEDS_CLOCK_DRIVER === - -Enable Clock Driver -------------------- -.. index:: CONFIGURE_APPLICATION_NEEDS_CLOCK_DRIVER - -*CONSTANT:* - ``CONFIGURE_APPLICATION_NEEDS_CLOCK_DRIVER`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -``CONFIGURE_APPLICATION_NEEDS_CLOCK_DRIVER`` is defined if the -application wishes to include the Clock Device Driver. - -**NOTES:** - -This device driver is responsible for providing a regular -interrupt which invokes the ``rtems_clock_tick`` directive. - -If neither the Clock Driver not Benchmark Timer is enabled and -the configuration parameter``CONFIGURE_APPLICATION_DOES_NOT_NEED_CLOCK_DRIVER`` is not defined, -then a compile time error will occur. - -.. COMMENT: === CONFIGURE_APPLICATION_NEEDS_TIMER_DRIVER === - -Enable the Benchmark Timer Driver ---------------------------------- -.. index:: CONFIGURE_APPLICATION_NEEDS_TIMER_DRIVER - -*CONSTANT:* - ``CONFIGURE_APPLICATION_NEEDS_TIMER_DRIVER`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -``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. - -**NOTES:** - -If neither the Clock Driver not Benchmark Timer is enabled and -the configuration parameter``CONFIGURE_APPLICATION_DOES_NOT_NEED_CLOCK_DRIVER`` is not defined, -then a compile time error will occur. - -.. COMMENT: === CONFIGURE_APPLICATION_DOES_NOT_NEED_CLOCK_DRIVER === - -Specify Clock and Benchmark Timer Drivers Are Not Needed --------------------------------------------------------- -.. index:: CONFIGURE_APPLICATION_DOES_NOT_NEED_CLOCK_DRIVER - -*CONSTANT:* - ``CONFIGURE_APPLICATION_DOES_NOT_NEED_CLOCK_DRIVER`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -``CONFIGURE_APPLICATION_DOES_NOT_NEED_CLOCK_DRIVER`` is defined when -the application does *NOT* want the Clock Device Driver and is *NOT* -using the Timer Driver. The inclusion or exclusion of the Clock Driver -must be explicit in user applications. - -**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. - -.. COMMENT: === CONFIGURE_APPLICATION_NEEDS_RTC_DRIVER === - -Enable Real-Time Clock Driver ------------------------------ -.. index:: CONFIGURE_APPLICATION_NEEDS_RTC_DRIVER - -*CONSTANT:* - ``CONFIGURE_APPLICATION_NEEDS_RTC_DRIVER`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -``CONFIGURE_APPLICATION_NEEDS_RTC_DRIVER`` is defined if the -application wishes to include the Real-Time Clock Driver. - -**NOTES:** - -Most BSPs do not include support for a real-time clock. This is because -many boards do not include the required hardware. - -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. - -.. COMMENT: === CONFIGURE_APPLICATION_NEEDS_WATCHDOG_DRIVER === - -Enable the Watchdog Device Driver ---------------------------------- -.. index:: CONFIGURE_APPLICATION_NEEDS_WATCHDOG_DRIVER - -*CONSTANT:* - ``CONFIGURE_APPLICATION_NEEDS_WATCHDOG_DRIVER`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -``CONFIGURE_APPLICATION_NEEDS_WATCHDOG_DRIVER`` -is defined if the application wishes to include the Watchdog Driver. - -**NOTES:** - -Most BSPs do not include support for a watchdog device driver. This is -because many boards do not include the required hardware. - -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. - -.. COMMENT: === CONFIGURE_APPLICATION_NEEDS_FRAME_BUFFER_DRIVER === - -Enable the Graphics Frame Buffer Device Driver ----------------------------------------------- -.. index:: CONFIGURE_APPLICATION_NEEDS_FRAME_BUFFER_DRIVER - -*CONSTANT:* - ``CONFIGURE_APPLICATION_NEEDS_FRAME_BUFFER_DRIVER`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -``CONFIGURE_APPLICATION_NEEDS_FRAME_BUFFER_DRIVER`` is defined -if the application wishes to include the BSP’s Frame Buffer Device Driver. - -**NOTES:** - -Most BSPs do not include support for a Frame Buffer Device Driver. This is -because many boards do not include the required hardware. - -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. - -.. COMMENT: === CONFIGURE_APPLICATION_NEEDS_STUB_DRIVER === - -Enable Stub Device Driver -------------------------- -.. index:: CONFIGURE_APPLICATION_NEEDS_STUB_DRIVER - -*CONSTANT:* - ``CONFIGURE_APPLICATION_NEEDS_STUB_DRIVER`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -``CONFIGURE_APPLICATION_NEEDS_STUB_DRIVER`` is defined if the -application wishes to include the Stub Device Driver. - -**NOTES:** - -This device driver simply provides entry points that return successful -and is primarily a test fixture. It is supported by all BSPs. - -.. COMMENT: === CONFIGURE_APPLICATION_PREREQUISITE_DRIVERS === - -Specify Application Prerequisite Device Drivers ------------------------------------------------ -.. index:: CONFIGURE_APPLICATION_PREREQUISITE_DRIVERS - -*CONSTANT:* - ``CONFIGURE_APPLICATION_PREREQUISITE_DRIVERS`` - -*DATA TYPE:* - device driver entry structures - -*RANGE:* - Undefined or set of device driver entry structures - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -``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 *FRONT* of the Device Driver Table -and initialized before any other drivers *EXCEPT* any BSP prerequisite -drivers. - -**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. - -.. COMMENT: XXX Add example - -.. COMMENT: === CONFIGURE_APPLICATION_EXTRA_DRIVERS === - -Specify Extra Application Device Drivers ----------------------------------------- -.. index:: CONFIGURE_APPLICATION_EXTRA_DRIVERS - -*CONSTANT:* - ``CONFIGURE_APPLICATION_EXTRA_DRIVERS`` - -*DATA TYPE:* - device driver entry structures - -*RANGE:* - Undefined or set of device driver entry structures - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -``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 *END* of the Device Driver Table. - -**NOTES:** - -None. - -.. COMMENT: === CONFIGURE_APPLICATION_NEEDS_NULL_DRIVER === - -Enable /dev/null Device Driver ------------------------------- -.. index:: CONFIGURE_APPLICATION_NEEDS_NULL_DRIVER -.. index:: /dev/null - -*CONSTANT:* - ``CONFIGURE_APPLICATION_NEEDS_NULL_DRIVER`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -This configuration variable is specified to enable */dev/null* -device driver. - -**NOTES:** - -This device driver is supported by all BSPs. - -.. COMMENT: === CONFIGURE_APPLICATION_NEEDS_ZERO_DRIVER === - -Enable /dev/zero Device Driver ------------------------------- -.. index:: CONFIGURE_APPLICATION_NEEDS_ZERO_DRIVER -.. index:: /dev/zero - -*CONSTANT:* - ``CONFIGURE_APPLICATION_NEEDS_ZERO_DRIVER`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -This configuration variable is specified to enable */dev/zero* -device driver. - -**NOTES:** - -This device driver is supported by all BSPs. - -.. COMMENT: === CONFIGURE_HAS_OWN_DEVICE_DRIVER_TABLE === - -Specifying Application Defined Device Driver Table --------------------------------------------------- -.. index:: CONFIGURE_HAS_OWN_DEVICE_DRIVER_TABLE - -*CONSTANT:* - ``CONFIGURE_HAS_OWN_DEVICE_DRIVER_TABLE`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default, indicating the ``<rtems/confdefs.h>`` - is providing the device driver table. - -**DESCRIPTION:** - -``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 ``rtems_driver_address_table`` entries named``_IO_Driver_address_table``. The application must also provide a const -variable ``_IO_Number_of_drivers`` of type ``size_t`` indicating the -number of entries in the ``_IO_Driver_address_table``. - -**NOTES:** - -It is expected that there the application would only rarely need to do this. - -.. COMMENT: === Multiprocessing Configuration === - -Multiprocessing Configuration -============================= - -This section defines the multiprocessing related system configuration -parameters supported by ``<rtems/confdefs.h>``. They are only used -if the Multiprocessing Support (distinct from the SMP support) is enabled -at configure time using the ``--enable-multiprocessing`` option. - -Additionally, this class of Configuration Constants are only applicable if``CONFIGURE_MP_APPLICATION`` is defined. - -.. COMMENT: === CONFIGURE_MP_APPLICATION === - -Specify Application Will Use Multiprocessing --------------------------------------------- -.. index:: CONFIGURE_MP_APPLICATION - -*CONSTANT:* - ``CONFIGURE_MP_APPLICATION`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**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. - -**NOTES:** - -This has no impact unless RTEMS was configured and built using the``--enable-multiprocessing`` option. - -.. COMMENT: === CONFIGURE_MP_NODE_NUMBER === - -Configure Node Number in Multiprocessor Configuration ------------------------------------------------------ -.. index:: CONFIGURE_MP_NODE_NUMBER - -*CONSTANT:* - ``CONFIGURE_MP_NODE_NUMBER`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Positive. - -*DEFAULT VALUE:* - The default value is ``NODE_NUMBER``, which is assumed to be - set by the compilation environment. - -**DESCRIPTION:** - -``CONFIGURE_MP_NODE_NUMBER`` is the node number of -this node in a multiprocessor system. - -**NOTES:** - -In the RTEMS Multiprocessing Test Suite, the node number is derived from -the Makefile variable ``NODE_NUMBER``. The same code is compiled with -the ``NODE_NUMBER`` set to different values. The test programs behave -differently based upon their node number. - -.. COMMENT: === CONFIGURE_MP_MAXIMUM_NODES === - -Configure Maximum Node in Multiprocessor Configuration ------------------------------------------------------- -.. index:: CONFIGURE_MP_MAXIMUM_NODES - -*CONSTANT:* - ``CONFIGURE_MP_MAXIMUM_NODES`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Positive. - -*DEFAULT VALUE:* - The default value is 2. - -**DESCRIPTION:** - -``CONFIGURE_MP_MAXIMUM_NODES`` is the maximum number of nodes in a -multiprocessor system. - -**NOTES:** - -None. - -.. COMMENT: === CONFIGURE_MP_MAXIMUM_GLOBAL_OBJECTS === - -Configure Maximum Global Objects in Multiprocessor Configuration ----------------------------------------------------------------- -.. index:: CONFIGURE_MP_MAXIMUM_GLOBAL_OBJECTS - -*CONSTANT:* - ``CONFIGURE_MP_MAXIMUM_GLOBAL_OBJECTS`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Positive. - -*DEFAULT VALUE:* - The default value is 32. - -**DESCRIPTION:** - -``CONFIGURE_MP_MAXIMUM_GLOBAL_OBJECTS`` is the maximum number of -concurrently active global objects in a multiprocessor system. - -**NOTES:** - -This value corresponds to the total number of objects which can be -created with the ``RTEMS_GLOBAL`` attribute. - -.. COMMENT: === CONFIGURE_MP_MAXIMUM_PROXIES === - -Configure Maximum Proxies in Multiprocessor Configuration ---------------------------------------------------------- -.. index:: CONFIGURE_MP_MAXIMUM_PROXIES - -*CONSTANT:* - ``CONFIGURE_MP_MAXIMUM_PROXIES`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Undefined or positive. - -*DEFAULT VALUE:* - The default value is 32. - -**DESCRIPTION:** - -``CONFIGURE_MP_MAXIMUM_PROXIES`` is the maximum number of concurrently -active thread/task proxies on this node in a multiprocessor system. - -**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. - -.. COMMENT: XXX - add xref to proxy discussion in MP chapter - -.. COMMENT: === CONFIGURE_MP_MPCI_TABLE_POINTER === - -Configure MPCI in Multiprocessor Configuration ----------------------------------------------- -.. index:: CONFIGURE_MP_MPCI_TABLE_POINTER - -*CONSTANT:* - ``CONFIGURE_MP_MPCI_TABLE_POINTER`` - -*DATA TYPE:* - pointer to ``rtems_mpci_table`` - -*RANGE:* - undefined or valid pointer - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -``CONFIGURE_MP_MPCI_TABLE_POINTER`` is the pointer to the -MPCI Configuration Table. The default value of this field is``&MPCI_table``. - -**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. - -.. COMMENT: === CONFIGURE_HAS_OWN_MULTIPROCESSING_TABLE === - -Do Not Generate Multiprocessor Configuration Table --------------------------------------------------- -.. index:: CONFIGURE_HAS_OWN_MULTIPROCESSING_TABLE - -*CONSTANT:* - ``CONFIGURE_HAS_OWN_MULTIPROCESSING_TABLE`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -``CONFIGURE_HAS_OWN_MULTIPROCESSING_TABLE`` is defined if the -application wishes to provide their own Multiprocessing Configuration -Table. The generated table is named ``Multiprocessing_configuration``. - -**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. - -.. COMMENT: === Ada Tasks === - -Ada Tasks -========= - -This section defines the system configuration parameters supported -by ``<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 ``--enable-ada`` configure option and the application specifies``CONFIGURE_GNAT_RTEMS``. - -Additionally RTEMS includes an Ada language binding to the Classic -API which has a test suite. This test suite is enabled only when``--enable-tests`` and ``--enable-expada`` are specified on the -configure command. - -.. COMMENT: === CONFIGURE_GNAT_RTEMS === - -Specify Application Includes Ada Code -------------------------------------- -.. index:: CONFIGURE_GNAT_RTEMS - -*CONSTANT:* - ``CONFIGURE_GNAT_RTEMS`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -``CONFIGURE_GNAT_RTEMS`` is defined to inform RTEMS that the GNAT -Ada run-time is to be used by the application. - -**NOTES:** - -This configuration parameter is critical as it makes``<rtems/confdefs.h>`` configure the resources (POSIX API Threads, -Mutexes, Condition Variables, and Keys) used implicitly by the GNAT -run-time. - -.. COMMENT: === CONFIGURE_MAXIMUM_ADA_TASKS === - -Specify the Maximum Number of Ada Tasks. ----------------------------------------- -.. index:: CONFIGURE_MAXIMUM_ADA_TASKS - -*CONSTANT:* - ``CONFIGURE_MAXIMUM_ADA_TASKS`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Undefined or positive. - -*DEFAULT VALUE:* - If ``CONFIGURE_GNAT_RTEMS`` is defined, then the - default value is 20, otherwise the default value is 0. - -**DESCRIPTION:** - -``CONFIGURE_MAXIMUM_ADA_TASKS`` is the number of Ada tasks that can -be concurrently active in the system. - -**NOTES:** - -None. - -.. COMMENT: === CONFIGURE_MAXIMUM_FAKE_ADA_TASKS === - -Specify the Maximum Fake Ada Tasks ----------------------------------- -.. index:: CONFIGURE_MAXIMUM_FAKE_ADA_TASKS - -*CONSTANT:* - .. index:: ``CONFIGURE_MAXIMUM_FAKE_ADA_TASKS`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Zero or positive. - -*DEFAULT VALUE:* - The default value is 0. - -**DESCRIPTION:** - -``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. - -**NOTES:** - -None. - -.. COMMENT: === PCI Library === - -PCI Library -=========== - -This section defines the system configuration parameters supported -by ``rtems/confdefs.h`` related to configuring the PCI Library -for RTEMS. - -The PCI Library startup behaviour can be configured in four different -ways depending on how ``CONFIGURE_PCI_CONFIG_LIB`` is defined: - -.. index:: PCI_LIB_AUTO - -``PCI_LIB_AUTO`` is used to enable the PCI auto configuration -software. PCI will be automatically probed, PCI buses enumerated, all -devices and bridges will be initialized using Plug & Play software -routines. The PCI device tree will be populated based on the PCI devices -found in the system, PCI devices will be configured by allocating address -region resources automatically in PCI space according to the BSP or host -bridge driver set up. - -.. index:: PCI_LIB_READ - -``PCI_LIB_READ`` is used to enable the PCI read configuration -software. The current PCI configuration is read to create the RAM -representation (the PCI device tree) of the PCI devices present. PCI devices -are assumed to already have been initialized and PCI buses enumerated, it is -therefore required that a BIOS or a boot loader has set up configuration space -prior to booting into RTEMS. - -.. index:: PCI_LIB_STATIC - -``PCI_LIB_STATIC`` is used to enable the PCI static configuration -software. The user provides a PCI tree with information how all PCI devices -are to be configured at compile time by linking in a custom``struct pci_bus pci_hb`` tree. The static PCI library will not probe PCI -for devices, instead it will assume that all devices defined by the user are -present, it will enumerate the PCI buses and configure all PCI devices in -static configuration accordingly. Since probe and allocation software is not -needed the startup is faster, has smaller footprint and does not require -dynamic memory allocation. - -.. index:: PCI_LIB_PERIPHERAL - -``PCI_LIB_PERIPHERAL`` is used to enable the PCI peripheral -configuration. It is similar to ``PCI_LIB_STATIC``, but it will never write -the configuration to the PCI devices since PCI peripherals are not allowed to -access PCI configuration space. - -Note that selecting PCI_LIB_STATIC or PCI_LIB_PERIPHERAL but not defining``pci_hb`` will reuslt in link errors. Note also that in these modes -Plug & Play is not performed. - -.. COMMENT: === Go Tasks === - -Go Tasks -======== - -.. COMMENT: === CONFIGURE_ENABLE_GO === - -Specify Application Includes Go Code ------------------------------------- -.. index:: CONFIGURE_ENABLE_GO - -*CONSTANT:* - ``CONFIGURE_ENABLE_GO`` - -*DATA TYPE:* - Boolean feature macro. - -*RANGE:* - Defined or undefined. - -*DEFAULT VALUE:* - This is not defined by default. - -**DESCRIPTION:** - -``CONFIGURE_ENABLE_GO`` is defined to inform RTEMS that the Go -run-time is to be used by the application. - -**NOTES:** - -The Go language support is experimental - -.. COMMENT: === CONFIGURE_MAXIMUM_GOROUTINES === - -Specify the maximum number of Go routines ------------------------------------------ -.. index:: CONFIGURE_MAXIMUM_GOROUTINES - -*CONSTANT:* - ``CONFIGURE_MAXIMUM_GOROUTINES`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Zero or positive. - -*DEFAULT VALUE:* - The default value is 400 - -**DESCRIPTION:** - -``CONFIGURE_MAXIMUM_GOROUTINES`` is defined to specify the maximum number of -Go routines. - -**NOTES:** - -The Go language support is experimental - -.. COMMENT: === CONFIGURE_MAXIMUM_GO_CHANNELS === - -Specify the maximum number of Go Channels ------------------------------------------ -.. index:: CONFIGURE_MAXIMUM_GO_CHANNELS - -*CONSTANT:* - ``CONFIGURE_MAXIMUM_GO_CHANNELS`` - -*DATA TYPE:* - Unsigned integer (``uint32_t``). - -*RANGE:* - Zero or positive. - -*DEFAULT VALUE:* - The default value is 500 - -**DESCRIPTION:** - -``CONFIGURE_MAXIMUM_GO_CHANNELS`` is defined to specify the maximum number -of Go channels. - -**NOTES:** - -The Go language support is experimental - -.. COMMENT: === Configuration Data Structures === - -Configuration Data Structures -============================= - -It is recommended that applications be configured using``<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. - -.. COMMENT: COPYRIGHT (c) 1988-2007. - -.. COMMENT: On-Line Applications Research Corporation (OAR). - -.. COMMENT: All rights reserved. - |