[ae68ff0] | 1 | @c |
---|
| 2 | @c COPYRIGHT (c) 1996. |
---|
| 3 | @c On-Line Applications Research Corporation (OAR). |
---|
| 4 | @c All rights reserved. |
---|
| 5 | @c |
---|
| 6 | |
---|
| 7 | @ifinfo |
---|
| 8 | @node Configuring a System, Configuring a System Configuration Table, EXTENSION_DELETE - Delete a extension set, Top |
---|
| 9 | @end ifinfo |
---|
| 10 | @chapter Configuring a System |
---|
| 11 | @ifinfo |
---|
| 12 | @menu |
---|
| 13 | * Configuring a System Configuration Table:: |
---|
| 14 | * Configuring a System RTEMS API Configuration Table:: |
---|
| 15 | * Configuring a System POSIX API Configuration Table:: |
---|
| 16 | * Configuring a System CPU Dependent Information Table:: |
---|
| 17 | * Configuring a System Initialization Task Table:: |
---|
| 18 | * Configuring a System Driver Address Table:: |
---|
| 19 | * Configuring a System User Extensions Table:: |
---|
| 20 | * Configuring a System Multiprocessor Configuration Table:: |
---|
| 21 | * Configuring a System Multiprocessor Communications Interface Table:: |
---|
| 22 | * Configuring a System Determining Memory Requirements:: |
---|
| 23 | * Configuring a System Sizing the RTEMS RAM Workspace:: |
---|
| 24 | @end menu |
---|
| 25 | @end ifinfo |
---|
| 26 | |
---|
| 27 | @ifinfo |
---|
| 28 | @node Configuring a System Configuration Table, Configuring a System RTEMS API Configuration Table, Configuring a System, Configuring a System |
---|
| 29 | @end ifinfo |
---|
| 30 | @section Configuration Table |
---|
| 31 | |
---|
| 32 | The RTEMS Configuration Table is used to tailor an |
---|
| 33 | application for its specific needs. For example, the user can |
---|
| 34 | configure the number of device drivers or which APIs may be used. |
---|
| 35 | THe address of the user-defined Configuration Table is passed as an |
---|
| 36 | argument to the initialize_executive directive, which MUST be |
---|
| 37 | the first RTEMS directive called. The RTEMS Configuration Table |
---|
[a94c5a5d] | 38 | is defined in the following @value{LANGUAGE} @value{STRUCTURE}: |
---|
[ae68ff0] | 39 | |
---|
[92c2ae1f] | 40 | @ifset is-C |
---|
[ae68ff0] | 41 | @example |
---|
| 42 | @group |
---|
| 43 | typedef struct @{ |
---|
| 44 | void *work_space_start; |
---|
| 45 | rtems_unsigned32 work_space_size; |
---|
| 46 | rtems_unsigned32 maximum_extensions; |
---|
| 47 | rtems_unsigned32 microseconds_per_tick; |
---|
| 48 | rtems_unsigned32 ticks_per_timeslice; |
---|
| 49 | rtems_unsigned32 maximum_devices; |
---|
| 50 | rtems_unsigned32 number_of_device_drivers; |
---|
| 51 | rtems_driver_address_table *Device_driver_table; |
---|
| 52 | rtems_extensions_table *User_extension_table; |
---|
| 53 | rtems_multiprocessing_table *User_multiprocessing_table; |
---|
| 54 | rtems_api_configuration_table *RTEMS_api_configuration; |
---|
| 55 | posix_api_configuration_table *POSIX_api_configuration; |
---|
| 56 | @} rtems_configuration_table; |
---|
| 57 | @end group |
---|
| 58 | @end example |
---|
[92c2ae1f] | 59 | @end ifset |
---|
| 60 | |
---|
| 61 | @ifset is-Ada |
---|
| 62 | @example |
---|
| 63 | type Configuration_Table is |
---|
| 64 | record |
---|
| 65 | Work_Space_Start : RTEMS.Address; |
---|
| 66 | Work_Space_Size : RTEMS.Unsigned32; |
---|
| 67 | Maximum_Extensions : RTEMS.Unsigned32; |
---|
| 68 | Microseconds_Per_Tick : RTEMS.Unsigned32; |
---|
| 69 | Ticks_Per_Timeslice : RTEMS.Unsigned32; |
---|
| 70 | Maximum_Devices : RTEMS.Unsigned32; |
---|
| 71 | Number_Of_Device_Drivers : RTEMS.Unsigned32; |
---|
| 72 | Device_Driver_Table : RTEMS.Driver_Address_Table_Pointer; |
---|
| 73 | User_Extension_Table : RTEMS.Extensions_Table_Pointer; |
---|
| 74 | User_Multiprocessing_Table : RTEMS.Multiprocessing_Table_Pointer; |
---|
| 75 | RTEMS_API_Configuration : RTEMS.API_Configuration_Table_Pointer; |
---|
| 76 | POSIX_API_Configuration : |
---|
| 77 | RTEMS.POSIX_API_Configuration_Table_Pointer; |
---|
| 78 | end record; |
---|
| 79 | |
---|
| 80 | type Configuration_Table_Pointer is access all Configuration_Table; |
---|
| 81 | @end example |
---|
| 82 | @end ifset |
---|
[ae68ff0] | 83 | |
---|
| 84 | @table @b |
---|
| 85 | @item work_space_start |
---|
| 86 | is the address of the RTEMS RAM Workspace. |
---|
| 87 | This area contains items such as the |
---|
| 88 | various object control blocks (TCBs, QCBs, ...) and task stacks. |
---|
| 89 | If the address is not aligned on a four-word boundary, then |
---|
| 90 | RTEMS will invoke the fatal error handler during |
---|
| 91 | initialize_executive. |
---|
| 92 | |
---|
| 93 | @item work_space_size |
---|
| 94 | is the calculated size of the |
---|
| 95 | RTEMS RAM Workspace. The section Sizing the RTEMS RAM Workspace |
---|
| 96 | details how to arrive at this number. |
---|
| 97 | |
---|
| 98 | @item microseconds_per_tick |
---|
| 99 | is number of microseconds per clock tick. |
---|
| 100 | |
---|
| 101 | @item ticks_per_timeslice |
---|
| 102 | is the number of clock ticks for a timeslice. |
---|
| 103 | |
---|
| 104 | @item maximum_devices |
---|
| 105 | is the maximum number of devices that can be registered. |
---|
| 106 | |
---|
| 107 | @item number_of_device_drivers |
---|
| 108 | is the number of device drivers for the system. There should be |
---|
| 109 | the same number of entries in the Device Driver Table. If this field |
---|
| 110 | is zero, then the User_driver_address_table entry should be NULL. |
---|
| 111 | |
---|
| 112 | @item Device_driver_table |
---|
| 113 | is the address of the Device Driver Table. This table contains the entry |
---|
| 114 | points for each device driver. If the number_of_device_drivers field is zero, |
---|
| 115 | then this entry should be NULL. The format of this table will be |
---|
| 116 | discussed below. |
---|
| 117 | |
---|
| 118 | @item User_extension_table |
---|
| 119 | is the address of the User |
---|
| 120 | Extension Table. This table contains the entry points for the |
---|
| 121 | static set of optional user extensions. If no user extensions |
---|
| 122 | are configured, then this entry should be NULL. The format of |
---|
| 123 | this table will be discussed below. |
---|
| 124 | |
---|
| 125 | @item User_multiprocessing_table |
---|
| 126 | is the address of the Multiprocessor Configuration Table. This |
---|
| 127 | table contains information needed by RTEMS only when used in a multiprocessor |
---|
| 128 | configuration. This field must be NULL when RTEMS is used in a |
---|
| 129 | single processor configuration. |
---|
| 130 | |
---|
| 131 | @item RTEMS_api_configuration |
---|
| 132 | is the address of the RTEMS API Configuration Table. This table |
---|
| 133 | contains information needed by the RTEMS API. This field should be |
---|
| 134 | NULL if the RTEMS API is not used. [NOTE: Currently the RTEMS API |
---|
| 135 | is required to support support components such as BSPs and libraries |
---|
| 136 | which use this API.] |
---|
| 137 | |
---|
| 138 | @item POSIX_api_configuration |
---|
| 139 | is the address of the POSIX API Configuration Table. This table |
---|
| 140 | contains information needed by the POSIX API. This field should be |
---|
| 141 | NULL if the POSIX API is not used. |
---|
| 142 | |
---|
| 143 | @end table |
---|
| 144 | |
---|
| 145 | @ifinfo |
---|
| 146 | @node Configuring a System RTEMS API Configuration Table, Configuring a System POSIX API Configuration Table, Configuring a System Configuration Table, Configuring a System |
---|
| 147 | @end ifinfo |
---|
| 148 | @section RTEMS API Configuration Table |
---|
| 149 | |
---|
| 150 | The RTEMS API Configuration Table is used to configure the |
---|
| 151 | managers which constitute the RTEMS API for a particular application. |
---|
| 152 | For example, the user can configure the maximum number of tasks for |
---|
| 153 | this application. The RTEMS API Configuration Table is defined in |
---|
[a94c5a5d] | 154 | the following @value{LANGUAGE} @value{STRUCTURE}: |
---|
[ae68ff0] | 155 | |
---|
[92c2ae1f] | 156 | @ifset is-C |
---|
[ae68ff0] | 157 | @example |
---|
| 158 | @group |
---|
| 159 | typedef struct @{ |
---|
| 160 | rtems_unsigned32 maximum_tasks; |
---|
| 161 | rtems_unsigned32 maximum_timers; |
---|
| 162 | rtems_unsigned32 maximum_semaphores; |
---|
| 163 | rtems_unsigned32 maximum_message_queues; |
---|
| 164 | rtems_unsigned32 maximum_partitions; |
---|
| 165 | rtems_unsigned32 maximum_regions; |
---|
| 166 | rtems_unsigned32 maximum_ports; |
---|
| 167 | rtems_unsigned32 maximum_periods; |
---|
| 168 | rtems_unsigned32 number_of_initialization_tasks; |
---|
| 169 | rtems_initialization_tasks_table *User_initialization_tasks_table; |
---|
| 170 | @} rtems_api_configuration_table; |
---|
| 171 | @end group |
---|
| 172 | @end example |
---|
[92c2ae1f] | 173 | @end ifset |
---|
| 174 | |
---|
| 175 | @ifset is-Ada |
---|
| 176 | @example |
---|
| 177 | type API_Configuration_Table is |
---|
| 178 | record |
---|
| 179 | Maximum_Tasks : RTEMS.Unsigned32; |
---|
| 180 | Maximum_Timers : RTEMS.Unsigned32; |
---|
| 181 | Maximum_Semaphores : RTEMS.Unsigned32; |
---|
| 182 | Maximum_Message_queues : RTEMS.Unsigned32; |
---|
| 183 | Maximum_Partitions : RTEMS.Unsigned32; |
---|
| 184 | Maximum_Regions : RTEMS.Unsigned32; |
---|
| 185 | Maximum_Ports : RTEMS.Unsigned32; |
---|
| 186 | Maximum_Periods : RTEMS.Unsigned32; |
---|
| 187 | Number_Of_Initialization_Tasks : RTEMS.Unsigned32; |
---|
| 188 | User_Initialization_Tasks_Table : |
---|
| 189 | RTEMS.Initialization_Tasks_Table_Pointer; |
---|
| 190 | end record; |
---|
| 191 | |
---|
| 192 | type API_Configuration_Table_Pointer is access all API_Configuration_Table; |
---|
| 193 | @end example |
---|
| 194 | @end ifset |
---|
[ae68ff0] | 195 | |
---|
| 196 | @table @b |
---|
| 197 | @item maximum_tasks |
---|
| 198 | is the maximum number of tasks that |
---|
| 199 | can be concurrently active (created) in the system including |
---|
| 200 | initialization tasks. |
---|
| 201 | |
---|
| 202 | @item maximum_timers |
---|
| 203 | is the maximum number of timers |
---|
| 204 | that can be concurrently active in the system. |
---|
| 205 | |
---|
| 206 | @item maximum_semaphores |
---|
| 207 | is the maximum number of |
---|
| 208 | semaphores that can be concurrently active in the system. |
---|
| 209 | |
---|
| 210 | @item maximum_message_queues |
---|
| 211 | is the maximum number of |
---|
| 212 | message queues that can be concurrently active in the system. |
---|
| 213 | |
---|
| 214 | @item maximum_partitions |
---|
| 215 | is the maximum number of |
---|
| 216 | partitions that can be concurrently active in the system. |
---|
| 217 | |
---|
| 218 | @item maximum_regions |
---|
| 219 | is the maximum number of regions |
---|
| 220 | that can be concurrently active in the system. |
---|
| 221 | |
---|
| 222 | @item maximum_ports |
---|
| 223 | is the maximum number of ports into |
---|
| 224 | dual-port memory areas that can be concurrently active in the |
---|
| 225 | system. |
---|
| 226 | |
---|
| 227 | @item number_of_initialization_tasks |
---|
| 228 | is the number of initialization tasks configured. At least one |
---|
| 229 | initialization task must be configured. |
---|
| 230 | |
---|
| 231 | @item User_initialization_tasks_table |
---|
| 232 | is the address of the Initialization Task Table. This table contains the |
---|
| 233 | information needed to create and start each of the |
---|
| 234 | initialization tasks. The format of this table will be discussed below. |
---|
| 235 | |
---|
| 236 | @end table |
---|
| 237 | |
---|
| 238 | @ifinfo |
---|
| 239 | @node Configuring a System POSIX API Configuration Table, Configuring a System CPU Dependent Information Table, Configuring a System RTEMS API Configuration Table, Configuring a System |
---|
| 240 | @end ifinfo |
---|
| 241 | @section POSIX API Configuration Table |
---|
| 242 | |
---|
| 243 | The POSIX API Configuration Table is used to configure the |
---|
| 244 | managers which constitute the POSIX API for a particular application. |
---|
| 245 | For example, the user can configure the maximum number of threads for |
---|
| 246 | this application. The POSIX API Configuration Table is defined in |
---|
[a94c5a5d] | 247 | the following @value{LANGUAGE} @value{STRUCTURE}: |
---|
[ae68ff0] | 248 | |
---|
[92c2ae1f] | 249 | @ifset is-C |
---|
[ae68ff0] | 250 | @example |
---|
| 251 | @group |
---|
| 252 | typedef struct @{ |
---|
[92c2ae1f] | 253 | void *(*thread_entry)(void *); |
---|
[ae68ff0] | 254 | @} posix_initialization_threads_table; |
---|
| 255 | |
---|
| 256 | typedef struct @{ |
---|
| 257 | int maximum_threads; |
---|
| 258 | int maximum_mutexes; |
---|
| 259 | int maximum_condition_variables; |
---|
| 260 | int maximum_keys; |
---|
| 261 | int maximum_queued_signals; |
---|
| 262 | int number_of_initialization_tasks; |
---|
| 263 | posix_initialization_threads_table *User_initialization_tasks_table; |
---|
| 264 | @} posix_api_configuration_table; |
---|
| 265 | @end group |
---|
| 266 | @end example |
---|
[92c2ae1f] | 267 | @end ifset |
---|
| 268 | |
---|
| 269 | @ifset is-Ada |
---|
| 270 | @example |
---|
| 271 | type POSIX_Thread_Entry is access procedure ( |
---|
| 272 | Argument : in RTEMS.Address |
---|
| 273 | ); |
---|
| 274 | |
---|
| 275 | type POSIX_Initialization_Threads_Table_Entry is |
---|
| 276 | record |
---|
| 277 | Thread_Entry : RTEMS.POSIX_Thread_Entry; |
---|
| 278 | end record; |
---|
| 279 | |
---|
| 280 | type POSIX_Initialization_Threads_Table is array |
---|
| 281 | ( RTEMS.Unsigned32 range <> ) of |
---|
| 282 | RTEMS.POSIX_Initialization_Threads_Table_Entry; |
---|
| 283 | |
---|
| 284 | type POSIX_Initialization_Threads_Table_Pointer is access all |
---|
| 285 | POSIX_Initialization_Threads_Table; |
---|
| 286 | |
---|
| 287 | type POSIX_API_Configuration_Table_Entry is |
---|
| 288 | record |
---|
| 289 | Maximum_Threads : Interfaces.C.Int; |
---|
| 290 | Maximum_Mutexes : Interfaces.C.Int; |
---|
| 291 | Maximum_Condition_Variables : Interfaces.C.Int; |
---|
| 292 | Maximum_Keys : Interfaces.C.Int; |
---|
| 293 | Maximum_Queued_Signals : Interfaces.C.Int; |
---|
| 294 | Number_Of_Initialization_Tasks : Interfaces.C.Int; |
---|
| 295 | User_Initialization_Tasks_Table : |
---|
| 296 | RTEMS.POSIX_Initialization_Threads_Table_Pointer; |
---|
| 297 | end record; |
---|
| 298 | |
---|
| 299 | type POSIX_API_Configuration_Table is array ( RTEMS.Unsigned32 range <> ) of |
---|
| 300 | RTEMS.POSIX_API_Configuration_Table_Entry; |
---|
| 301 | |
---|
| 302 | type POSIX_API_Configuration_Table_Pointer is access all |
---|
| 303 | RTEMS.POSIX_API_Configuration_Table; |
---|
| 304 | @end example |
---|
| 305 | @end ifset |
---|
[ae68ff0] | 306 | |
---|
| 307 | @table @b |
---|
| 308 | @item maximum_threads |
---|
| 309 | is the maximum number of threads that |
---|
| 310 | can be concurrently active (created) in the system including |
---|
| 311 | initialization threads. |
---|
| 312 | |
---|
| 313 | @item maximum_mutexes |
---|
| 314 | is the maximum number of mutexes that can be concurrently |
---|
| 315 | active in the system. |
---|
| 316 | |
---|
| 317 | @item maximum_condition_variables |
---|
| 318 | is the maximum number of condition variables that can be |
---|
| 319 | concurrently active in the system. |
---|
| 320 | |
---|
| 321 | @item maximum_keys |
---|
| 322 | is the maximum number of keys that can be concurrently active in the system. |
---|
| 323 | |
---|
| 324 | @item maximum_queued_signals |
---|
| 325 | is the maximum number of queued signals that can be concurrently |
---|
| 326 | pending in the system. |
---|
| 327 | |
---|
| 328 | @item number_of_initialization_threads |
---|
| 329 | is the number of initialization threads configured. At least one |
---|
| 330 | initialization threads must be configured. |
---|
| 331 | |
---|
| 332 | @item User_initialization_threads_table |
---|
| 333 | is the address of the Initialization Threads Table. This table contains the |
---|
| 334 | information needed to create and start each of the initialization threads. |
---|
| 335 | The format of each entry in this table is defined in the |
---|
[7e8a1fc] | 336 | posix_initialization_threads_table @value{STRUCTURE}. |
---|
[ae68ff0] | 337 | |
---|
| 338 | @end table |
---|
| 339 | |
---|
| 340 | @ifinfo |
---|
| 341 | @node Configuring a System CPU Dependent Information Table, Configuring a System Initialization Task Table, Configuring a System POSIX API Configuration Table, Configuring a System |
---|
| 342 | @end ifinfo |
---|
| 343 | @section CPU Dependent Information Table |
---|
| 344 | |
---|
| 345 | The CPU Dependent Information Table is used to |
---|
| 346 | describe processor dependent information required by RTEMS. |
---|
| 347 | This table is generally used to supply RTEMS with information |
---|
| 348 | only known by the Board Support Package. The contents of this |
---|
| 349 | table are discussed in the CPU Dependent Information Table |
---|
[17a3c69] | 350 | chapter of the Applications Supplement document for a specific |
---|
[ae68ff0] | 351 | target processor. |
---|
| 352 | |
---|
| 353 | @ifinfo |
---|
| 354 | @node Configuring a System Initialization Task Table, Configuring a System Driver Address Table, Configuring a System CPU Dependent Information Table, Configuring a System |
---|
| 355 | @end ifinfo |
---|
| 356 | @section Initialization Task Table |
---|
| 357 | |
---|
| 358 | The Initialization Task Table is used to describe |
---|
| 359 | each of the user initialization tasks to the Initialization |
---|
| 360 | Manager. The table contains one entry for each initialization |
---|
| 361 | task the user wishes to create and start. The fields of this |
---|
| 362 | data structure directly correspond to arguments to the |
---|
| 363 | task_create and task_start directives. The number of entries is |
---|
| 364 | found in the number_of_initialization_tasks entry in the |
---|
| 365 | Configuration Table. The format of each entry in the |
---|
[7e8a1fc] | 366 | Initialization Task Table is defined in the following @value{LANGUAGE} |
---|
| 367 | @value{STRUCTURE}: |
---|
[ae68ff0] | 368 | |
---|
[92c2ae1f] | 369 | @ifset is-C |
---|
[ae68ff0] | 370 | @example |
---|
| 371 | typedef struct @{ |
---|
| 372 | rtems_name name; |
---|
| 373 | rtems_unsigned32 stack_size; |
---|
| 374 | rtems_task_priority initial_priority; |
---|
| 375 | rtems_attribute attribute_set; |
---|
| 376 | rtems_task_entry entry_point; |
---|
| 377 | rtems_mode mode_set; |
---|
| 378 | rtems_task_argument argument; |
---|
| 379 | @} rtems_initialization_tasks_table; |
---|
| 380 | @end example |
---|
[92c2ae1f] | 381 | @end ifset |
---|
| 382 | |
---|
| 383 | @ifset is-Ada |
---|
| 384 | @example |
---|
| 385 | type Initialization_Tasks_Table_Entry is |
---|
| 386 | record |
---|
| 387 | Name : RTEMS.Name; -- task name |
---|
| 388 | Stack_Size : RTEMS.Unsigned32; -- task stack size |
---|
| 389 | Initial_Priority : RTEMS.Task_priority; -- task priority |
---|
| 390 | Attribute_Set : RTEMS.Attribute; -- task attributes |
---|
| 391 | Entry_Point : RTEMS.Task_Entry; -- task entry point |
---|
| 392 | Mode_Set : RTEMS.Mode; -- task initial mode |
---|
| 393 | Argument : RTEMS.Unsigned32; -- task argument |
---|
| 394 | end record; |
---|
| 395 | |
---|
| 396 | type Initialization_Tasks_Table is array ( RTEMS.Unsigned32 range <> ) of |
---|
| 397 | RTEMS.Initialization_Tasks_Table_Entry; |
---|
| 398 | |
---|
| 399 | type Initialization_Tasks_Table_Pointer is access all |
---|
| 400 | Initialization_Tasks_Table; |
---|
| 401 | @end example |
---|
| 402 | @end ifset |
---|
[ae68ff0] | 403 | |
---|
| 404 | @table @b |
---|
| 405 | @item name |
---|
| 406 | is the name of this initialization task. |
---|
| 407 | |
---|
| 408 | @item stack_size |
---|
| 409 | is the size of the stack for this initialization task. |
---|
| 410 | |
---|
| 411 | @item initial_priority |
---|
| 412 | is the priority of this initialization task. |
---|
| 413 | |
---|
| 414 | @item attribute_set |
---|
| 415 | is the attribute set used during creation of this initialization task. |
---|
| 416 | |
---|
| 417 | @item entry_point |
---|
| 418 | is the address of the entry point of this initialization task. |
---|
| 419 | |
---|
| 420 | @item mode_set |
---|
| 421 | is the initial execution mode of this initialization task. |
---|
| 422 | |
---|
| 423 | @item argument |
---|
| 424 | is the initial argument for this initialization task. |
---|
| 425 | |
---|
| 426 | @end table |
---|
| 427 | |
---|
| 428 | A typical declaration for an Initialization Task Table might appear as follows: |
---|
| 429 | |
---|
[92c2ae1f] | 430 | @ifset is-C |
---|
[ae68ff0] | 431 | @example |
---|
| 432 | rtems_initialization_tasks_table |
---|
| 433 | Initialization_tasks[2] = @{ |
---|
| 434 | @{ INIT_1_NAME, |
---|
| 435 | 1024, |
---|
| 436 | 1, |
---|
| 437 | DEFAULT_ATTRIBUTES, |
---|
| 438 | Init_1, |
---|
| 439 | DEFAULT_MODES, |
---|
| 440 | 1 |
---|
| 441 | |
---|
| 442 | @}, |
---|
| 443 | @{ INIT_2_NAME, |
---|
| 444 | 1024, |
---|
| 445 | 250, |
---|
| 446 | FLOATING_POINT, |
---|
| 447 | Init_2, |
---|
[92c2ae1f] | 448 | NO_PREEMPT, |
---|
[ae68ff0] | 449 | 2 |
---|
| 450 | |
---|
| 451 | @} |
---|
| 452 | @}; |
---|
| 453 | @end example |
---|
[92c2ae1f] | 454 | @end ifset |
---|
| 455 | |
---|
| 456 | @ifset is-Ada |
---|
| 457 | @example |
---|
| 458 | Initialization_Tasks : aliased RTEMS.Initialization_Tasks_Table( 1 .. 2 ) := ( |
---|
| 459 | (INIT_1_NAME, |
---|
| 460 | 1024, |
---|
| 461 | 1, |
---|
| 462 | RTEMS.Default_Attributes, |
---|
| 463 | Init_1'Access, |
---|
| 464 | RTEMS.Default_Modes, |
---|
| 465 | 1), |
---|
| 466 | (INIT_2_NAME, |
---|
| 467 | 1024, |
---|
| 468 | 250, |
---|
| 469 | RTEMS.Floating_Point, |
---|
| 470 | Init_2'Access, |
---|
| 471 | RTEMS.No_Preempt, |
---|
| 472 | 2) |
---|
| 473 | ); |
---|
| 474 | @end example |
---|
| 475 | @end ifset |
---|
[ae68ff0] | 476 | |
---|
| 477 | @ifinfo |
---|
| 478 | @node Configuring a System Driver Address Table, Configuring a System User Extensions Table, Configuring a System Initialization Task Table, Configuring a System |
---|
| 479 | @end ifinfo |
---|
| 480 | @section Driver Address Table |
---|
| 481 | |
---|
| 482 | The Device Driver Table is used to inform the I/O |
---|
| 483 | Manager of the set of entry points for each device driver |
---|
| 484 | configured in the system. The table contains one entry for each |
---|
| 485 | device driver required by the application. The number of |
---|
| 486 | entries is defined in the number_of_device_drivers entry in the |
---|
| 487 | Configuration Table. The format of each entry in the Device |
---|
[61389eac] | 488 | Driver Table is defined in |
---|
[a94c5a5d] | 489 | the following @value{LANGUAGE} @value{STRUCTURE}: |
---|
[ae68ff0] | 490 | |
---|
[92c2ae1f] | 491 | @ifset is-C |
---|
[ae68ff0] | 492 | @example |
---|
| 493 | typedef struct @{ |
---|
| 494 | rtems_device_driver_entry initialization; |
---|
| 495 | rtems_device_driver_entry open; |
---|
| 496 | rtems_device_driver_entry close; |
---|
| 497 | rtems_device_driver_entry read; |
---|
| 498 | rtems_device_driver_entry write; |
---|
| 499 | rtems_device_driver_entry control; |
---|
| 500 | @} rtems_driver_address_table; |
---|
| 501 | @end example |
---|
[92c2ae1f] | 502 | @end ifset |
---|
| 503 | |
---|
| 504 | @ifset is-Ada |
---|
| 505 | @example |
---|
| 506 | type Driver_Address_Table_Entry is |
---|
| 507 | record |
---|
| 508 | Initialization : RTEMS.Device_Driver_Entry; |
---|
| 509 | Open : RTEMS.Device_Driver_Entry; |
---|
| 510 | Close : RTEMS.Device_Driver_Entry; |
---|
| 511 | Read : RTEMS.Device_Driver_Entry; |
---|
| 512 | Write : RTEMS.Device_Driver_Entry; |
---|
| 513 | Control : RTEMS.Device_Driver_Entry; |
---|
| 514 | end record; |
---|
| 515 | |
---|
| 516 | type Driver_Address_Table is array ( RTEMS.Unsigned32 range <> ) of |
---|
| 517 | RTEMS.Driver_Address_Table_Entry; |
---|
| 518 | |
---|
| 519 | type Driver_Address_Table_Pointer is access all Driver_Address_Table; |
---|
| 520 | @end example |
---|
| 521 | @end ifset |
---|
[ae68ff0] | 522 | |
---|
| 523 | @table @b |
---|
| 524 | @item initialization |
---|
| 525 | is the address of the entry point called by io_initialize |
---|
| 526 | to initialize a device driver and its associated devices. |
---|
| 527 | |
---|
| 528 | @item open |
---|
| 529 | is the address of the entry point called by io_open. |
---|
| 530 | |
---|
| 531 | @item close |
---|
| 532 | is the address of the entry point called by io_close. |
---|
| 533 | |
---|
| 534 | @item read |
---|
| 535 | is the address of the entry point called by io_read. |
---|
| 536 | |
---|
| 537 | @item write |
---|
| 538 | is the address of the entry point called by io_write. |
---|
| 539 | |
---|
| 540 | @item control |
---|
| 541 | is the address of the entry point called by io_control. |
---|
| 542 | |
---|
| 543 | @end table |
---|
| 544 | |
---|
| 545 | Driver entry points configured as NULL will always |
---|
[a94c5a5d] | 546 | return a status code of @code{SUCCESSFUL}. No user code will be |
---|
[ae68ff0] | 547 | executed in this situation. |
---|
| 548 | |
---|
| 549 | A typical declaration for a Device Driver Table might appear as follows: |
---|
| 550 | |
---|
[92c2ae1f] | 551 | @ifset is-C |
---|
[ae68ff0] | 552 | @example |
---|
| 553 | rtems_driver_address_table Driver_table[2] = @{ |
---|
| 554 | @{ tty_initialize, tty_open, tty_close, /* major = 0 */ |
---|
| 555 | tty_read, tty_write, tty_control |
---|
| 556 | @}, |
---|
| 557 | @{ lp_initialize, lp_open, lp_close, /* major = 1 */ |
---|
| 558 | NULL, lp_write, lp_control |
---|
| 559 | @} |
---|
| 560 | @}; |
---|
| 561 | @end example |
---|
[92c2ae1f] | 562 | @end ifset |
---|
| 563 | |
---|
| 564 | @ifset is-Ada |
---|
| 565 | @example |
---|
| 566 | @end example |
---|
| 567 | @end ifset |
---|
[ae68ff0] | 568 | |
---|
| 569 | More information regarding the construction and |
---|
| 570 | operation of device drivers is provided in the I/O Manager |
---|
| 571 | chapter. |
---|
| 572 | |
---|
| 573 | @ifinfo |
---|
| 574 | @node Configuring a System User Extensions Table, Configuring a System Multiprocessor Configuration Table, Configuring a System Driver Address Table, Configuring a System |
---|
| 575 | @end ifinfo |
---|
| 576 | @section User Extensions Table |
---|
| 577 | |
---|
| 578 | The User Extensions Table is used to inform RTEMS of |
---|
| 579 | the optional user-supplied static extension set. This table |
---|
| 580 | contains one entry for each possible extension. The entries are |
---|
| 581 | called at critical times in the life of the system and |
---|
| 582 | individual tasks. The application may create dynamic extensions |
---|
| 583 | in addition to this single static set. The format of each entry |
---|
[7e8a1fc] | 584 | in the User Extensions Table is defined in the following @value{LANGUAGE} |
---|
| 585 | @value{STRUCTURE}: |
---|
[ae68ff0] | 586 | |
---|
[022fbf3e] | 587 | @ifset is-C |
---|
| 588 | @example |
---|
[92c2ae1f] | 589 | typedef User_extensions_routine rtems_extension; |
---|
| 590 | typedef User_extensions_thread_create_extension rtems_task_create_extension; |
---|
| 591 | typedef User_extensions_thread_delete_extension rtems_task_delete_extension; |
---|
| 592 | typedef User_extensions_thread_start_extension rtems_task_start_extension; |
---|
| 593 | typedef User_extensions_thread_restart_extension rtems_task_restart_extension; |
---|
| 594 | typedef User_extensions_thread_switch_extension rtems_task_switch_extension; |
---|
| 595 | typedef User_extensions_thread_begin_extension rtems_task_begin_extension; |
---|
| 596 | typedef User_extensions_thread_exitted_extension rtems_task_exitted_extension; |
---|
| 597 | typedef User_extensions_fatal_extension rtems_fatal_extension; |
---|
| 598 | |
---|
| 599 | typedef User_extensions_Table rtems_extensions_table; |
---|
| 600 | |
---|
[ae68ff0] | 601 | typedef struct @{ |
---|
[92c2ae1f] | 602 | rtems_task_create_extension thread_create; |
---|
| 603 | rtems_task_start_extension thread_start; |
---|
| 604 | rtems_task_restart_extension thread_restart; |
---|
| 605 | rtems_task_delete_extension thread_delete; |
---|
| 606 | rtems_task_switch_extension thread_switch; |
---|
| 607 | rtems_task_post_switch_extension thread_post_switch; |
---|
| 608 | rtems_task_begin_extension thread_begin; |
---|
| 609 | rtems_task_exitted_extension thread_exitted; |
---|
| 610 | rtems_fatal_extension fatal; |
---|
[ae68ff0] | 611 | @} User_extensions_Table; |
---|
| 612 | @end example |
---|
[92c2ae1f] | 613 | @end ifset |
---|
| 614 | |
---|
| 615 | @ifset is-Ada |
---|
| 616 | @example |
---|
| 617 | type Extensions_Table_Entry is |
---|
| 618 | record |
---|
| 619 | Thread_Create : RTEMS.Thread_Create_Extension; |
---|
| 620 | Thread_Start : RTEMS.Thread_Start_Extension; |
---|
| 621 | Thread_Restart : RTEMS.Thread_Restart_Extension; |
---|
| 622 | Thread_Delete : RTEMS.Thread_Delete_Extension; |
---|
| 623 | Thread_Switch : RTEMS.Thread_Switch_Extension; |
---|
| 624 | Thread_Post_Switch : RTEMS.Thread_Post_Switch_Extension; |
---|
| 625 | Thread_Begin : RTEMS.Thread_Begin_Extension; |
---|
| 626 | Thread_Exitted : RTEMS.Thread_Exitted_Extension; |
---|
| 627 | Fatal : RTEMS.Fatal_Error_Extension; |
---|
| 628 | end record; |
---|
| 629 | @end example |
---|
| 630 | @end ifset |
---|
[ae68ff0] | 631 | |
---|
| 632 | @table @b |
---|
| 633 | |
---|
| 634 | @item thread_create |
---|
| 635 | is the address of the |
---|
| 636 | user-supplied subroutine for the TASK_CREATE extension. If this |
---|
| 637 | extension for task creation is defined, it is called from the |
---|
| 638 | task_create directive. A value of NULL indicates that no |
---|
| 639 | extension is provided. |
---|
| 640 | |
---|
| 641 | @item thread_start |
---|
| 642 | is the address of the user-supplied |
---|
| 643 | subroutine for the TASK_START extension. If this extension for |
---|
| 644 | task initiation is defined, it is called from the task_start |
---|
| 645 | directive. A value of NULL indicates that no extension is |
---|
| 646 | provided. |
---|
| 647 | |
---|
| 648 | @item thread_restart |
---|
| 649 | is the address of the user-supplied |
---|
| 650 | subroutine for the TASK_RESTART extension. If this extension |
---|
| 651 | for task re-initiation is defined, it is called from the |
---|
| 652 | task_restart directive. A value of NULL indicates that no |
---|
| 653 | extension is provided. |
---|
| 654 | |
---|
| 655 | @item thread_delete |
---|
| 656 | is the address of the user-supplied |
---|
| 657 | subroutine for the TASK_DELETE extension. If this RTEMS |
---|
| 658 | extension for task deletion is defined, it is called from the |
---|
| 659 | task_delete directive. A value of NULL indicates that no |
---|
| 660 | extension is provided. |
---|
| 661 | |
---|
| 662 | @item thread_switch |
---|
| 663 | is the address of the user-supplied |
---|
| 664 | subroutine for the task context switch extension. This |
---|
| 665 | subroutine is called from RTEMS dispatcher after the current |
---|
| 666 | task has been swapped out but before the new task has been |
---|
| 667 | swapped in. A value of NULL indicates that no extension is |
---|
| 668 | provided. As this routine is invoked after saving the current |
---|
| 669 | task's context and before restoring the heir task's context, it |
---|
| 670 | is not necessary for this routine to save and restore any |
---|
| 671 | registers. |
---|
| 672 | |
---|
| 673 | @item thread_post_switch |
---|
| 674 | is the address of the |
---|
| 675 | user-supplied subroutine for the post task context switch |
---|
| 676 | extension. This subroutine is called from RTEMS dispatcher in |
---|
| 677 | the context of the task which has just been swapped in. |
---|
| 678 | |
---|
| 679 | @item thread_begin |
---|
| 680 | is the address of the user-supplied |
---|
| 681 | subroutine which is invoked immediately before a task begins |
---|
| 682 | execution. It is invoked in the context of the beginning task. |
---|
| 683 | A value of NULL indicates that no extension is provided. |
---|
| 684 | |
---|
| 685 | @item thread_exitted |
---|
| 686 | is the address of the user-supplied |
---|
| 687 | subroutine which is invoked when a task exits. This procedure |
---|
| 688 | is responsible for some action which will allow the system to |
---|
| 689 | continue execution (i.e. delete or restart the task) or to |
---|
| 690 | terminate with a fatal error. If this field is set to NULL, the |
---|
| 691 | default RTEMS task_exitted handler will be invoked. |
---|
| 692 | |
---|
| 693 | @item fatal |
---|
| 694 | is the address of the user-supplied |
---|
| 695 | subroutine for the FATAL extension. This RTEMS extension of |
---|
| 696 | fatal error handling is called from the fatal_error_occurred |
---|
| 697 | directive. If the user's fatal error handler returns or if this |
---|
| 698 | entry is NULL then the default RTEMS fatal error handler will be |
---|
| 699 | executed. |
---|
| 700 | |
---|
| 701 | @end table |
---|
| 702 | |
---|
| 703 | A typical declaration for a User Extension Table |
---|
| 704 | which defines the TASK_CREATE, TASK_DELETE, TASK_SWITCH, and |
---|
| 705 | FATAL extension might appear as follows: |
---|
| 706 | |
---|
[92c2ae1f] | 707 | @ifset is-C |
---|
[ae68ff0] | 708 | @example |
---|
| 709 | rtems_extensions_table User_extensions = @{ |
---|
| 710 | task_create_extension, |
---|
| 711 | NULL, |
---|
| 712 | NULL, |
---|
| 713 | task_delete_extension, |
---|
| 714 | task_switch_extension, |
---|
| 715 | NULL, |
---|
| 716 | NULL, |
---|
| 717 | fatal_extension |
---|
| 718 | @}; |
---|
| 719 | @end example |
---|
[92c2ae1f] | 720 | @end ifset |
---|
| 721 | |
---|
| 722 | @ifset is-Ada |
---|
| 723 | User_Extensions : RTEMS.Extensions_Table := ( |
---|
| 724 | Task_Create_Extension'Access, |
---|
| 725 | null, |
---|
| 726 | null, |
---|
| 727 | Task_Delete_Extension'Access, |
---|
| 728 | Task_Switch_Extension'Access, |
---|
| 729 | null, |
---|
| 730 | null, |
---|
| 731 | Fatal_Extension'Access |
---|
| 732 | ); |
---|
| 733 | @example |
---|
| 734 | |
---|
| 735 | @end example |
---|
| 736 | @end ifset |
---|
[ae68ff0] | 737 | |
---|
| 738 | More information regarding the user extensions is |
---|
| 739 | provided in the User Extensions chapter. |
---|
| 740 | |
---|
| 741 | @ifinfo |
---|
| 742 | @node Configuring a System Multiprocessor Configuration Table, Configuring a System Multiprocessor Communications Interface Table, Configuring a System User Extensions Table, Configuring a System |
---|
| 743 | @end ifinfo |
---|
| 744 | @section Multiprocessor Configuration Table |
---|
| 745 | |
---|
| 746 | The Multiprocessor Configuration Table contains |
---|
| 747 | information needed when using RTEMS in a multiprocessor |
---|
| 748 | configuration. Many of the details associated with configuring |
---|
| 749 | a multiprocessor system are dependent on the multiprocessor |
---|
| 750 | communications layer provided by the user. The address of the |
---|
| 751 | Multiprocessor Configuration Table should be placed in the |
---|
| 752 | User_multiprocessing_table entry in the primary Configuration |
---|
| 753 | Table. Further details regarding many of the entries in the |
---|
| 754 | Multiprocessor Configuration Table will be provided in the |
---|
| 755 | Multiprocessing chapter. The format of the Multiprocessor |
---|
[61389eac] | 756 | Configuration Table is defined in |
---|
[a94c5a5d] | 757 | the following @value{LANGUAGE} @value{STRUCTURE}: |
---|
[ae68ff0] | 758 | |
---|
[92c2ae1f] | 759 | @ifset is-C |
---|
[ae68ff0] | 760 | @example |
---|
| 761 | typedef struct @{ |
---|
| 762 | rtems_unsigned32 node; |
---|
| 763 | rtems_unsigned32 maximum_nodes; |
---|
| 764 | rtems_unsigned32 maximum_global_objects; |
---|
| 765 | rtems_unsigned32 maximum_proxies; |
---|
| 766 | rtems_mpci_table *User_mpci_table; |
---|
| 767 | @} rtems_multiprocessing_table; |
---|
| 768 | @end example |
---|
[92c2ae1f] | 769 | @end ifset |
---|
| 770 | |
---|
| 771 | @ifset is-Ada |
---|
| 772 | @example |
---|
| 773 | type Multiprocessing_Table is |
---|
| 774 | record |
---|
| 775 | Node : RTEMS.Unsigned32; |
---|
| 776 | Maximum_Nodes : RTEMS.Unsigned32; |
---|
| 777 | Maximum_Global_Objects : RTEMS.Unsigned32; |
---|
| 778 | Maximum_Proxies : RTEMS.Unsigned32; |
---|
| 779 | User_MPCI_Table : RTEMS.MPCI_Table_Pointer; |
---|
| 780 | end record; |
---|
| 781 | |
---|
| 782 | type Multiprocessing_Table_Pointer is access all Multiprocessing_Table; |
---|
| 783 | @end example |
---|
| 784 | @end ifset |
---|
[ae68ff0] | 785 | |
---|
| 786 | @table @b |
---|
| 787 | @item node |
---|
| 788 | is a unique processor identifier |
---|
| 789 | and is used in routing messages between nodes in a |
---|
| 790 | multiprocessor configuration. Each processor must have a unique |
---|
| 791 | node number. RTEMS assumes that node numbers start at one and |
---|
| 792 | increase sequentially. This assumption can be used to advantage |
---|
| 793 | by the user-supplied MPCI layer. Typically, this requirement is |
---|
| 794 | made when the node numbers are used to calculate the address of |
---|
| 795 | inter-processor communication links. Zero should be avoided as |
---|
| 796 | a node number because some MPCI layers use node zero to |
---|
| 797 | represent broadcasted packets. Thus, it is recommended that |
---|
| 798 | node numbers start at one and increase sequentially. |
---|
| 799 | |
---|
| 800 | @item maximum_nodes |
---|
| 801 | is the number of processor nodes in the system. |
---|
| 802 | |
---|
| 803 | @item maximum_global_objects |
---|
| 804 | is the maximum number of global objects which can exist at any |
---|
| 805 | given moment in the entire system. If this parameter is not the |
---|
| 806 | same on all nodes in the system, then a fatal error is generated |
---|
| 807 | to inform the user that the system is inconsistent. |
---|
| 808 | |
---|
| 809 | @item maximum_proxies |
---|
| 810 | is the maximum number of proxies which can exist at any given moment |
---|
| 811 | on this particular node. A proxy is a substitute task control block |
---|
| 812 | which represent a task residing on a remote node when that task blocks |
---|
| 813 | on a remote object. Proxies are used in situations in which delayed |
---|
| 814 | interaction is required with a remote node. |
---|
| 815 | |
---|
| 816 | @item User_mpci_table |
---|
| 817 | is the address of the Multiprocessor Communications Interface |
---|
| 818 | Table. This table contains the entry points of user-provided functions |
---|
| 819 | which constitute the multiprocessor communications layer. This table |
---|
| 820 | must be provided in multiprocessor configurations with all |
---|
| 821 | entries configured. The format of this table and details |
---|
| 822 | regarding its entries can be found in the next section. |
---|
| 823 | |
---|
| 824 | @end table |
---|
| 825 | |
---|
| 826 | @ifinfo |
---|
| 827 | @node Configuring a System Multiprocessor Communications Interface Table, Configuring a System Determining Memory Requirements, Configuring a System Multiprocessor Configuration Table, Configuring a System |
---|
| 828 | @end ifinfo |
---|
| 829 | @section Multiprocessor Communications Interface Table |
---|
| 830 | |
---|
[61389eac] | 831 | The format of this table is defined in |
---|
[a94c5a5d] | 832 | the following @value{LANGUAGE} @value{STRUCTURE}: |
---|
[ae68ff0] | 833 | |
---|
[92c2ae1f] | 834 | @ifset is-C |
---|
[ae68ff0] | 835 | @example |
---|
| 836 | typedef struct @{ |
---|
[92c2ae1f] | 837 | rtems_unsigned32 default_timeout; /* in ticks */ |
---|
[ae68ff0] | 838 | rtems_unsigned32 maximum_packet_size; |
---|
| 839 | rtems_mpci_initialization_entry initialization; |
---|
| 840 | rtems_mpci_get_packet_entry get_packet; |
---|
| 841 | rtems_mpci_return_packet_entry return_packet; |
---|
| 842 | rtems_mpci_send_entry send; |
---|
| 843 | rtems_mpci_receive_entry receive; |
---|
| 844 | @} rtems_mpci_table; |
---|
| 845 | @end example |
---|
[92c2ae1f] | 846 | @end ifset |
---|
| 847 | |
---|
| 848 | @ifset is-Ada |
---|
| 849 | @example |
---|
| 850 | type MPCI_Table is |
---|
| 851 | record |
---|
| 852 | Default_Timeout : RTEMS.Unsigned32; -- in ticks |
---|
| 853 | Maximum_Packet_Size : RTEMS.Unsigned32; |
---|
| 854 | Initialization : RTEMS.MPCI_Initialization_Entry; |
---|
| 855 | Get_Packet : RTEMS.MPCI_Get_Packet_Entry; |
---|
| 856 | Return_Packet : RTEMS.MPCI_Return_Packet_Entry; |
---|
| 857 | Send : RTEMS.MPCI_Send_Entry; |
---|
| 858 | Receive : RTEMS.MPCI_Receive_Entry; |
---|
| 859 | end record; |
---|
| 860 | |
---|
| 861 | type MPCI_Table_Pointer is access all MPCI_Table; |
---|
| 862 | @end example |
---|
| 863 | @end ifset |
---|
[ae68ff0] | 864 | |
---|
| 865 | @table @b |
---|
| 866 | @item default_timeout |
---|
| 867 | is the default maximum length of time a task should block waiting for |
---|
| 868 | a response to a directive which results in communication with a remote node. |
---|
| 869 | The maximum length of time is a function the user supplied |
---|
| 870 | multiprocessor communications layer and the media used. This |
---|
| 871 | timeout only applies to directives which would not block if the |
---|
| 872 | operation were performed locally. |
---|
| 873 | |
---|
| 874 | @item maximum_packet_size |
---|
| 875 | is the size in bytes of the longest packet which the MPCI layer is capable |
---|
| 876 | of sending. This value should represent the total number of bytes available |
---|
| 877 | for a RTEMS interprocessor messages. |
---|
| 878 | |
---|
| 879 | @item initialization |
---|
| 880 | is the address of the entry point for the initialization procedure of the |
---|
| 881 | user supplied multiprocessor communications layer. |
---|
| 882 | |
---|
| 883 | @item get_packet |
---|
| 884 | is the address of the entry point for the procedure called by RTEMS to |
---|
| 885 | obtain a packet from the user supplied multiprocessor communications layer. |
---|
| 886 | |
---|
| 887 | @item return_packet |
---|
| 888 | is the address of the entry point for the procedure called by RTEMS to |
---|
| 889 | return a packet to the user supplied multiprocessor communications layer. |
---|
| 890 | |
---|
| 891 | @item send |
---|
| 892 | is the address of the entry point for the procedure called by RTEMS to |
---|
| 893 | send an envelope to another node. This procedure is part of the user |
---|
| 894 | supplied multiprocessor communications layer. |
---|
| 895 | |
---|
| 896 | @item receive |
---|
| 897 | is the address of the entry point for the |
---|
| 898 | procedure called by RTEMS to retrieve an envelope containing a |
---|
| 899 | message from another node. This procedure is part of the user |
---|
| 900 | supplied multiprocessor communications layer. |
---|
| 901 | |
---|
| 902 | @end table |
---|
| 903 | |
---|
| 904 | More information regarding the required functionality of these |
---|
| 905 | entry points is provided in the Multiprocessor chapter. |
---|
| 906 | |
---|
| 907 | @ifinfo |
---|
| 908 | @node Configuring a System Determining Memory Requirements, Configuring a System Sizing the RTEMS RAM Workspace, Configuring a System Multiprocessor Communications Interface Table, Configuring a System |
---|
| 909 | @end ifinfo |
---|
| 910 | @section Determining Memory Requirements |
---|
| 911 | |
---|
| 912 | Since memory is a critical resource in many real-time |
---|
| 913 | embedded systems, RTEMS was specifically designed to allow |
---|
| 914 | unused managers to be excluded from the run-time environment. |
---|
| 915 | This allows the application designer the flexibility to tailor |
---|
| 916 | RTEMS to most efficiently meet system requirements while still |
---|
| 917 | satisfying even the most stringent memory constraints. As |
---|
| 918 | result, the size of the RTEMS executive is application |
---|
[17a3c69] | 919 | dependent. A Memory Requirements worksheet is provided in the |
---|
[ae68ff0] | 920 | Applications Supplement document for a specific target |
---|
| 921 | processor. This worksheet can be used to calculate the memory |
---|
| 922 | requirements of a custom RTEMS run-time environment. To insure |
---|
| 923 | that enough memory is allocated for future versions of RTEMS, |
---|
| 924 | the application designer should round these memory requirements |
---|
| 925 | up. The following managers may be optionally excluded: |
---|
| 926 | |
---|
| 927 | @itemize @bullet |
---|
| 928 | @item signal |
---|
| 929 | @item region |
---|
| 930 | @item dual ported memory |
---|
| 931 | @item event |
---|
| 932 | @item multiprocessing |
---|
| 933 | @item partition |
---|
| 934 | @item timer |
---|
| 935 | @item semaphore |
---|
| 936 | @item message |
---|
| 937 | @item rate monotonic |
---|
| 938 | @end itemize |
---|
| 939 | |
---|
| 940 | RTEMS based applications must somehow provide memory |
---|
| 941 | for RTEMS' code and data space. Although RTEMS' data space must |
---|
| 942 | be in RAM, its code space can be located in either ROM or RAM. |
---|
| 943 | In addition, the user must allocate RAM for the RTEMS RAM |
---|
| 944 | Workspace. The size of this area is application dependent and |
---|
| 945 | can be calculated using the formula provided in the Memory |
---|
[17a3c69] | 946 | Requirements chapter of the Applications Supplement document |
---|
[ae68ff0] | 947 | for a specific target processor. |
---|
| 948 | |
---|
| 949 | All RTEMS data variables and routine names used by |
---|
| 950 | RTEMS begin with the underscore ( _ ) character followed by an |
---|
| 951 | upper-case letter. If RTEMS is linked with an application, then |
---|
| 952 | the application code should NOT contain any symbols which begin |
---|
| 953 | with the underscore character and followed by an upper-case |
---|
| 954 | letter to avoid any naming conflicts. All RTEMS directive names |
---|
| 955 | should be treated as reserved words. |
---|
| 956 | |
---|
| 957 | @ifinfo |
---|
| 958 | @node Configuring a System Sizing the RTEMS RAM Workspace, Multiprocessing Manager, Configuring a System Determining Memory Requirements, Configuring a System |
---|
| 959 | @end ifinfo |
---|
| 960 | @section Sizing the RTEMS RAM Workspace |
---|
| 961 | |
---|
| 962 | The RTEMS RAM Workspace is a user-specified block of |
---|
| 963 | memory reserved for use by RTEMS. The application should NOT |
---|
| 964 | modify this memory. This area consists primarily of the RTEMS |
---|
| 965 | data structures whose exact size depends upon the values |
---|
| 966 | specified in the Configuration Table. In addition, task stacks |
---|
| 967 | and floating point context areas are dynamically allocated from |
---|
| 968 | the RTEMS RAM Workspace. |
---|
| 969 | |
---|
| 970 | The starting address of the RTEMS RAM Workspace must |
---|
| 971 | be aligned on a four-byte boundary. Failure to properly align |
---|
| 972 | the workspace area will result in the fatal_error_occurred |
---|
[a94c5a5d] | 973 | directive being invoked with the @code{INVALID_ADDRESS} error code. |
---|
[ae68ff0] | 974 | |
---|
| 975 | A worksheet is provided in the Memory Requirements |
---|
[17a3c69] | 976 | chapter of the Applications Supplement document for a specific |
---|
[ae68ff0] | 977 | target processor to assist the user in calculating the minimum |
---|
| 978 | size of the RTEMS RAM Workspace for each application. The value |
---|
| 979 | calculated with this worksheet is the minimum value that should |
---|
| 980 | be specified as the work_space_size parameter of the |
---|
| 981 | Configuration Table. The user is cautioned that future versions |
---|
| 982 | of RTEMS may not have the same memory requirements per object. |
---|
| 983 | Although the value calculated is sufficient for a particular |
---|
| 984 | target processor and release of RTEMS, memory usage is subject |
---|
| 985 | to change across versions and target processors. The user is |
---|
| 986 | advised to allocate somewhat more memory than the worksheet |
---|
| 987 | recommends to insure compatibility with future releases for a |
---|
| 988 | specific target processor and other target processors. To avoid |
---|
| 989 | problems, the user should recalculate the memory requirements |
---|
| 990 | each time one of the following events occurs: |
---|
| 991 | |
---|
| 992 | @itemize @bullet |
---|
| 993 | @item a configuration parameter is modified, |
---|
| 994 | @item task or interrupt stack requirements change, |
---|
| 995 | @item task floating point attribute is altered, |
---|
| 996 | @item RTEMS is upgraded, or |
---|
| 997 | @item the target processor is changed. |
---|
| 998 | @end itemize |
---|
| 999 | |
---|
| 1000 | Failure to provide enough space in the RTEMS RAM |
---|
| 1001 | Workspace will result in the fatal_error_occurred directive |
---|
| 1002 | being invoked with the appropriate error code. |
---|