.. SPDX-License-Identifier: CC-BY-SA-4.0 .. Copyright (C) 1988, 2008 On-Line Applications Research Corporation (OAR) BSP Related Configuration Options ================================= This section describes configuration options related to the BSP. Some configuration options may have a BSP-specific setting which is defined by ````. The BSP-specific settings can be disabled by the :ref:`CONFIGURE_DISABLE_BSP_SETTINGS` configuration option. .. index:: BSP_IDLE_TASK_BODY .. _BSP_IDLE_TASK_BODY: 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 .. index:: BSP_IDLE_TASK_STACK_SIZE .. _BSP_IDLE_TASK_STACK_SIZE: 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``. .. index:: BSP_INITIAL_EXTENSION .. _BSP_INITIAL_EXTENSION: 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. .. index:: BSP_INTERRUPT_STACK_SIZE .. _BSP_INTERRUPT_STACK_SIZE: 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. .. index:: BSP_MAXIMUM_DEVICES .. _BSP_MAXIMUM_DEVICES: 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 ```` when ``CONFIGURE_USE_DEVFS_AS_BASE_FILESYSTEM`` is specified. .. index:: CONFIGURE_BSP_PREREQUISITE_DRIVERS .. _CONFIGURE_BSP_PREREQUISITE_DRIVERS: 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. .. index:: CONFIGURE_DISABLE_BSP_SETTINGS .. _CONFIGURE_DISABLE_BSP_SETTINGS: CONFIGURE_DISABLE_BSP_SETTINGS ------------------------------ CONSTANT: ``CONFIGURE_DISABLE_BSP_SETTINGS`` OPTION TYPE: This configuration option is a boolean feature define. DEFAULT CONFIGURATION: If this configuration option is undefined, then the described feature is not enabled. DESCRIPTION: In case this configuration option is defined, then the following BSP related configuration options are undefined: - :ref:`BSP_IDLE_TASK_BODY` - :ref:`BSP_IDLE_TASK_STACK_SIZE` - :ref:`BSP_INITIAL_EXTENSION` - :ref:`BSP_INTERRUPT_STACK_SIZE` - :ref:`CONFIGURE_BSP_PREREQUISITE_DRIVERS` - :ref:`CONFIGURE_MALLOC_BSP_SUPPORTS_SBRK` NOTES: None. .. index:: CONFIGURE_MALLOC_BSP_SUPPORTS_SBRK .. _CONFIGURE_MALLOC_BSP_SUPPORTS_SBRK: CONFIGURE_MALLOC_BSP_SUPPORTS_SBRK ---------------------------------- CONSTANT: ``CONFIGURE_MALLOC_BSP_SUPPORTS_SBRK`` OPTION TYPE: This configuration option is a boolean feature define. DEFAULT CONFIGURATION: If this configuration option is undefined, then the described feature is not enabled. DESCRIPTION: If * this configuration option is defined by the BSP * and :ref:`CONFIGURE_DISABLE_BSP_SETTINGS` is undefined, then not all memory is made available to the C Program Heap immediately at system initialization time. When :c:func:`malloc()` or other standard memory allocation functions are unable to allocate memory, they will call the BSP supplied :c:func:`sbrk()` function to obtain more memory. NOTES: This option should not be defined by the application. Only the BSP knows how it allocates memory to the C Program Heap.