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Diffstat (limited to 'c-user/config/device-driver.rst')
| -rw-r--r-- | c-user/config/device-driver.rst | 92 |
1 files changed, 52 insertions, 40 deletions
diff --git a/c-user/config/device-driver.rst b/c-user/config/device-driver.rst index e783111..0a18b2d 100644 --- a/c-user/config/device-driver.rst +++ b/c-user/config/device-driver.rst @@ -1,5 +1,6 @@ .. SPDX-License-Identifier: CC-BY-SA-4.0 +.. Copyright (C) 2020 embedded brains GmbH (http://www.embedded-brains.de) .. Copyright (C) 1988, 2008 On-Line Applications Research Corporation (OAR) Device Driver Configuration @@ -34,7 +35,7 @@ NOTES: of using the Hello World example as the baseline for an application and leaving out a clock tick source. - The application must define exactly one of the following configuration options + The application shall define exactly one of the following configuration options * :ref:`CONFIGURE_APPLICATION_NEEDS_CLOCK_DRIVER`, @@ -54,23 +55,26 @@ CONFIGURE_APPLICATION_EXTRA_DRIVERS CONSTANT: ``CONFIGURE_APPLICATION_EXTRA_DRIVERS`` -DATA TYPE: - device driver entry structures - -RANGE: - Undefined or set of device driver entry structures +OPTION TYPE: + This configuration option is an initializer define. DEFAULT VALUE: - This is not defined by default. + The default value is the empty list. + +VALUE CONSTRAINTS: + The value of this configuration option shall be a list of initializers for + structures of type :c:type:`rtems_driver_address_table`. 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. + The value of this configuration option is used to initialize the Device + Driver Table. NOTES: - None. + The value of this configuration option is placed after the entries of other + device driver configuration options. + + See :ref:`CONFIGURE_APPLICATION_PREREQUISITE_DRIVERS` for an alternative + placement of application device driver initializers. .. index:: CONFIGURE_APPLICATION_NEEDS_CLOCK_DRIVER @@ -97,7 +101,7 @@ NOTES: The Clock Driver is responsible for providing a regular interrupt which invokes a clock tick directive. - The application must define exactly one of the following configuration options + The application shall define exactly one of the following configuration options * `CONFIGURE_APPLICATION_NEEDS_CLOCK_DRIVER`, @@ -372,7 +376,7 @@ NOTES: The Benchmark Timer Driver is intended for the benchmark tests of the RTEMS Testsuite. Applications should not use this driver. - The application must define exactly one of the following configuration options + The application shall define exactly one of the following configuration options * :ref:`CONFIGURE_APPLICATION_NEEDS_CLOCK_DRIVER`, @@ -445,28 +449,27 @@ CONFIGURE_APPLICATION_PREREQUISITE_DRIVERS CONSTANT: ``CONFIGURE_APPLICATION_PREREQUISITE_DRIVERS`` -DATA TYPE: - device driver entry structures - -RANGE: - Undefined or set of device driver entry structures +OPTION TYPE: + This configuration option is an initializer define. DEFAULT VALUE: - This is not defined by default. + The default value is the empty list. + +VALUE CONSTRAINTS: + The value of this configuration option shall be a list of initializers for + structures of type :c:type:`rtems_driver_address_table`. 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. + The value of this configuration option is used to initialize the Device + Driver Table. 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. + The value of this configuration option is placed after the entries defined by + :ref:`CONFIGURE_BSP_PREREQUISITE_DRIVERS` and before all other device driver + configuration options. + + See :ref:`CONFIGURE_APPLICATION_EXTRA_DRIVERS` for an alternative placement + of application device driver initializers. .. index:: CONFIGURE_MAXIMUM_DRIVERS @@ -478,24 +481,33 @@ CONFIGURE_MAXIMUM_DRIVERS CONSTANT: ``CONFIGURE_MAXIMUM_DRIVERS`` -DATA TYPE: - Unsigned integer (``uint32_t``). - -RANGE: - Zero or positive. +OPTION TYPE: + This configuration option is an integer define. 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. + configuration options. + +VALUE CONSTRAINTS: + The value of this configuration option shall satisfy all of the following + constraints: + + * It shall be less than or equal to ``SIZE_MAX``. + + * It shall be greater than or equal than the number of statically configured + device drivers. + + * It shall be less than or equal to a + BSP-specific and application-specific value which depends on the size of the + memory available to the application. DESCRIPTION: - ``CONFIGURE_MAXIMUM_DRIVERS`` is defined as the number of device drivers - per node. + The value of this configuration option defines the number of device drivers. NOTES: If the application will dynamically install device drivers, then this - configuration parameter must be larger than the number of statically + configuration parameter shall be larger than the number of statically configured device drivers. Drivers configured using the - ``CONFIGURE_APPLICATIONS_NEEDS_XXX_DRIVER`` configuration parameters are + ``CONFIGURE_APPLICATIONS_NEEDS_XXX_DRIVER`` configuration options are statically installed. |