diff options
Diffstat (limited to 'c-user/dual-ported-memory/directives.rst')
| -rw-r--r-- | c-user/dual-ported-memory/directives.rst | 403 |
1 files changed, 403 insertions, 0 deletions
diff --git a/c-user/dual-ported-memory/directives.rst b/c-user/dual-ported-memory/directives.rst new file mode 100644 index 0000000..b96e3c7 --- /dev/null +++ b/c-user/dual-ported-memory/directives.rst @@ -0,0 +1,403 @@ +.. SPDX-License-Identifier: CC-BY-SA-4.0 + +.. Copyright (C) 2020, 2021 embedded brains GmbH & Co. KG +.. Copyright (C) 1988, 2008 On-Line Applications Research Corporation (OAR) + +.. This file is part of the RTEMS quality process and was automatically +.. generated. If you find something that needs to be fixed or +.. worded better please post a report or patch to an RTEMS mailing list +.. or raise a bug report: +.. +.. https://www.rtems.org/bugs.html +.. +.. For information on updating and regenerating please refer to the How-To +.. section in the Software Requirements Engineering chapter of the +.. RTEMS Software Engineering manual. The manual is provided as a part of +.. a release. For development sources please refer to the online +.. documentation at: +.. +.. https://docs.rtems.org + +.. _DualPortedMemoryManagerDirectives: + +Directives +========== + +This section details the directives of the Dual-Ported Memory Manager. A +subsection is dedicated to each of this manager's directives and lists the +calling sequence, parameters, description, return values, and notes of the +directive. + +.. Generated from spec:/rtems/dpmem/if/create + +.. raw:: latex + + \clearpage + +.. index:: rtems_port_create() +.. index:: create a port + +.. _InterfaceRtemsPortCreate: + +rtems_port_create() +------------------- + +Creates a port. + +.. rubric:: CALLING SEQUENCE: + +.. code-block:: c + + rtems_status_code rtems_port_create( + rtems_name name, + void *internal_start, + void *external_start, + uint32_t length, + rtems_id *id + ); + +.. rubric:: PARAMETERS: + +``name`` + This parameter is the object name of the port. + +``internal_start`` + This parameter is the internal start address of the memory area. + +``external_start`` + This parameter is the external start address of the memory area. + +``length`` + This parameter is the length in bytes of the memory area. + +``id`` + This parameter is the pointer to an :ref:`InterfaceRtemsId` object. When + the directive call is successful, the identifier of the created port will + be stored in this object. + +.. rubric:: DESCRIPTION: + +This directive creates a port which resides on the local node. The port has +the user-defined object name specified in ``name``. The assigned object +identifier is returned in ``id``. This identifier is used to access the port +with other dual-ported memory port related directives. + +.. rubric:: RETURN VALUES: + +:c:macro:`RTEMS_SUCCESSFUL` + The requested operation was successful. + +:c:macro:`RTEMS_INVALID_NAME` + The ``name`` parameter was invalid. + +:c:macro:`RTEMS_INVALID_ADDRESS` + The ``id`` parameter was `NULL + <https://en.cppreference.com/w/c/types/NULL>`_. + +:c:macro:`RTEMS_INVALID_ADDRESS` + The ``internal_start`` parameter was not properly aligned. + +:c:macro:`RTEMS_INVALID_ADDRESS` + The ``external_start`` parameter was not properly aligned. + +:c:macro:`RTEMS_TOO_MANY` + There was no inactive object available to create a port. The number of + port available to the application is configured through the + :ref:`CONFIGURE_MAXIMUM_PORTS` application configuration option. + +.. rubric:: NOTES: + +The ``internal_start`` and ``external_start`` parameters must be on a boundary +defined by the target processor architecture. + +For control and maintenance of the port, RTEMS allocates a :term:`DPCB` from +the local DPCB free pool and initializes it. + +.. rubric:: CONSTRAINTS: + +The following constraints apply to this directive: + +* The directive may be called from within device driver initialization context. + +* The directive may be called from within task context. + +* The directive may obtain and release the object allocator mutex. This may + cause the calling task to be preempted. + +* The number of ports available to the application is configured through the + :ref:`CONFIGURE_MAXIMUM_PORTS` application configuration option. + +* Where the object class corresponding to the directive is configured to use + unlimited objects, the directive may allocate memory from the RTEMS + Workspace. + +.. Generated from spec:/rtems/dpmem/if/ident + +.. raw:: latex + + \clearpage + +.. index:: rtems_port_ident() + +.. _InterfaceRtemsPortIdent: + +rtems_port_ident() +------------------ + +Identifies a port by the object name. + +.. rubric:: CALLING SEQUENCE: + +.. code-block:: c + + rtems_status_code rtems_port_ident( rtems_name name, rtems_id *id ); + +.. rubric:: PARAMETERS: + +``name`` + This parameter is the object name to look up. + +``id`` + This parameter is the pointer to an :ref:`InterfaceRtemsId` object. When + the directive call is successful, the object identifier of an object with + the specified name will be stored in this object. + +.. rubric:: DESCRIPTION: + +This directive obtains a port identifier associated with the port name +specified in ``name``. + +.. rubric:: RETURN VALUES: + +:c:macro:`RTEMS_SUCCESSFUL` + The requested operation was successful. + +:c:macro:`RTEMS_INVALID_ADDRESS` + The ``id`` parameter was `NULL + <https://en.cppreference.com/w/c/types/NULL>`_. + +:c:macro:`RTEMS_INVALID_NAME` + The ``name`` parameter was 0. + +:c:macro:`RTEMS_INVALID_NAME` + There was no object with the specified name on the local node. + +.. rubric:: NOTES: + +If the port name is not unique, then the port identifier will match the first +port with that name in the search order. However, this port identifier is not +guaranteed to correspond to the desired port. + +The objects are searched from lowest to the highest index. Only the local node +is searched. + +The port identifier is used with other dual-ported memory related directives to +access the port. + +.. rubric:: CONSTRAINTS: + +The following constraints apply to this directive: + +* The directive may be called from within any runtime context. + +* The directive will not cause the calling task to be preempted. + +.. Generated from spec:/rtems/dpmem/if/delete + +.. raw:: latex + + \clearpage + +.. index:: rtems_port_delete() +.. index:: delete a port + +.. _InterfaceRtemsPortDelete: + +rtems_port_delete() +------------------- + +Deletes the port. + +.. rubric:: CALLING SEQUENCE: + +.. code-block:: c + + rtems_status_code rtems_port_delete( rtems_id id ); + +.. rubric:: PARAMETERS: + +``id`` + This parameter is the port identifier. + +.. rubric:: DESCRIPTION: + +This directive deletes the port specified by ``id``. + +.. rubric:: RETURN VALUES: + +:c:macro:`RTEMS_SUCCESSFUL` + The requested operation was successful. + +:c:macro:`RTEMS_INVALID_ID` + There was no port associated with the identifier specified by ``id``. + +.. rubric:: NOTES: + +The :term:`DPCB` for the deleted port is reclaimed by RTEMS. + +.. rubric:: CONSTRAINTS: + +The following constraints apply to this directive: + +* The directive may be called from within device driver initialization context. + +* The directive may be called from within task context. + +* The directive may obtain and release the object allocator mutex. This may + cause the calling task to be preempted. + +* The calling task does not have to be the task that created the object. Any + local task that knows the object identifier can delete the object. + +* Where the object class corresponding to the directive is configured to use + unlimited objects, the directive may free memory to the RTEMS Workspace. + +.. Generated from spec:/rtems/dpmem/if/external-to-internal + +.. raw:: latex + + \clearpage + +.. index:: rtems_port_external_to_internal() +.. index:: convert external to internal address + +.. _InterfaceRtemsPortExternalToInternal: + +rtems_port_external_to_internal() +--------------------------------- + +Converts the external address to the internal address. + +.. rubric:: CALLING SEQUENCE: + +.. code-block:: c + + rtems_status_code rtems_port_external_to_internal( + rtems_id id, + void *external, + void **internal + ); + +.. rubric:: PARAMETERS: + +``id`` + This parameter is the port identifier. + +``external`` + This parameter is the external address to convert. + +``internal`` + This parameter is the pointer to a ``void`` pointer object. When the + directive call is successful, the external address associated with the + internal address will be stored in this object. + +.. rubric:: DESCRIPTION: + +This directive converts a dual-ported memory address from external to internal +representation for the specified port. If the given external address is +invalid for the specified port, then the internal address is set to the given +external address. + +.. rubric:: RETURN VALUES: + +:c:macro:`RTEMS_SUCCESSFUL` + The requested operation was successful. + +:c:macro:`RTEMS_INVALID_NAME` + The ``id`` parameter was invalid. + +:c:macro:`RTEMS_INVALID_ADDRESS` + The ``internal`` parameter was `NULL + <https://en.cppreference.com/w/c/types/NULL>`_. + +.. rubric:: CONSTRAINTS: + +The following constraints apply to this directive: + +* The directive may be called from within interrupt context. + +* The directive may be called from within device driver initialization context. + +* The directive may be called from within task context. + +* The directive will not cause the calling task to be preempted. + +.. Generated from spec:/rtems/dpmem/if/internal-to-external + +.. raw:: latex + + \clearpage + +.. index:: rtems_port_internal_to_external() +.. index:: convert internal to external address + +.. _InterfaceRtemsPortInternalToExternal: + +rtems_port_internal_to_external() +--------------------------------- + +Converts the internal address to the external address. + +.. rubric:: CALLING SEQUENCE: + +.. code-block:: c + + rtems_status_code rtems_port_internal_to_external( + rtems_id id, + void *internal, + void **external + ); + +.. rubric:: PARAMETERS: + +``id`` + This parameter is the port identifier. + +``internal`` + This parameter is the internal address to convert. + +``external`` + This parameter is the pointer to a ``void`` pointer object. When the + directive call is successful, the external address associated with the + internal address will be stored in this object. + +.. rubric:: DESCRIPTION: + +This directive converts a dual-ported memory address from internal to external +representation so that it can be passed to owner of the DPMA represented by the +specified port. If the given internal address is an invalid dual-ported +address, then the external address is set to the given internal address. + +.. rubric:: RETURN VALUES: + +:c:macro:`RTEMS_SUCCESSFUL` + The requested operation was successful. + +:c:macro:`RTEMS_INVALID_NAME` + The ``id`` parameter was invalid. + +:c:macro:`RTEMS_INVALID_ADDRESS` + The ``external`` parameter was `NULL + <https://en.cppreference.com/w/c/types/NULL>`_. + +.. rubric:: CONSTRAINTS: + +The following constraints apply to this directive: + +* The directive may be called from within interrupt context. + +* The directive may be called from within device driver initialization context. + +* The directive may be called from within task context. + +* The directive will not cause the calling task to be preempted. |