Lab Checkoff
Dependencies: SDFileSystem TextLCD mbed-rtos mbed wave_player FATFileSystem
rt_Task.c
00001 /*---------------------------------------------------------------------------- 00002 * RL-ARM - RTX 00003 *---------------------------------------------------------------------------- 00004 * Name: RT_TASK.C 00005 * Purpose: Task functions and system start up. 00006 * Rev.: V4.60 00007 *---------------------------------------------------------------------------- 00008 * 00009 * Copyright (c) 1999-2009 KEIL, 2009-2012 ARM Germany GmbH 00010 * All rights reserved. 00011 * Redistribution and use in source and binary forms, with or without 00012 * modification, are permitted provided that the following conditions are met: 00013 * - Redistributions of source code must retain the above copyright 00014 * notice, this list of conditions and the following disclaimer. 00015 * - Redistributions in binary form must reproduce the above copyright 00016 * notice, this list of conditions and the following disclaimer in the 00017 * documentation and/or other materials provided with the distribution. 00018 * - Neither the name of ARM nor the names of its contributors may be used 00019 * to endorse or promote products derived from this software without 00020 * specific prior written permission. 00021 * 00022 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 00023 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 00024 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 00025 * ARE DISCLAIMED. IN NO EVENT SHALL COPYRIGHT HOLDERS AND CONTRIBUTORS BE 00026 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 00027 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 00028 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 00029 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 00030 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 00031 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 00032 * POSSIBILITY OF SUCH DAMAGE. 00033 *---------------------------------------------------------------------------*/ 00034 00035 #include "rt_TypeDef.h" 00036 #include "RTX_Config.h" 00037 #include "rt_System.h" 00038 #include "rt_Task.h" 00039 #include "rt_List.h" 00040 #include "rt_MemBox.h" 00041 #include "rt_Robin.h" 00042 #include "rt_HAL_CM.h" 00043 00044 /*---------------------------------------------------------------------------- 00045 * Global Variables 00046 *---------------------------------------------------------------------------*/ 00047 00048 /* Running and next task info. */ 00049 struct OS_TSK os_tsk; 00050 00051 /* Task Control Blocks of idle demon */ 00052 struct OS_TCB os_idle_TCB; 00053 00054 00055 /*---------------------------------------------------------------------------- 00056 * Local Functions 00057 *---------------------------------------------------------------------------*/ 00058 00059 OS_TID rt_get_TID (void) { 00060 U32 tid; 00061 00062 for (tid = 1; tid <= os_maxtaskrun; tid++) { 00063 if (os_active_TCB[tid-1] == NULL) { 00064 return ((OS_TID)tid); 00065 } 00066 } 00067 return (0); 00068 } 00069 00070 #if defined (__CC_ARM) && !defined (__MICROLIB) 00071 /*--------------------------- __user_perthread_libspace ---------------------*/ 00072 extern void *__libspace_start; 00073 00074 void *__user_perthread_libspace (void) { 00075 /* Provide a separate libspace for each task. */ 00076 if (os_tsk.run == NULL) { 00077 /* RTX not running yet. */ 00078 return (&__libspace_start); 00079 } 00080 return (void *)(os_tsk.run->std_libspace); 00081 } 00082 #endif 00083 00084 /*--------------------------- rt_init_context -------------------------------*/ 00085 00086 void rt_init_context (P_TCB p_TCB, U8 priority, FUNCP task_body) { 00087 /* Initialize general part of the Task Control Block. */ 00088 p_TCB->cb_type = TCB; 00089 p_TCB->state = READY; 00090 p_TCB->prio = priority; 00091 p_TCB->p_lnk = NULL; 00092 p_TCB->p_rlnk = NULL; 00093 p_TCB->p_dlnk = NULL; 00094 p_TCB->p_blnk = NULL; 00095 p_TCB->delta_time = 0; 00096 p_TCB->interval_time = 0; 00097 p_TCB->events = 0; 00098 p_TCB->waits = 0; 00099 p_TCB->stack_frame = 0; 00100 00101 rt_init_stack (p_TCB, task_body); 00102 } 00103 00104 00105 /*--------------------------- rt_switch_req ---------------------------------*/ 00106 00107 void rt_switch_req (P_TCB p_new) { 00108 /* Switch to next task (identified by "p_new"). */ 00109 os_tsk.new_tsk = p_new; 00110 p_new->state = RUNNING; 00111 DBG_TASK_SWITCH(p_new->task_id); 00112 } 00113 00114 00115 /*--------------------------- rt_dispatch -----------------------------------*/ 00116 00117 void rt_dispatch (P_TCB next_TCB) { 00118 /* Dispatch next task if any identified or dispatch highest ready task */ 00119 /* "next_TCB" identifies a task to run or has value NULL (=no next task) */ 00120 if (next_TCB == NULL) { 00121 /* Running task was blocked: continue with highest ready task */ 00122 next_TCB = rt_get_first (&os_rdy); 00123 rt_switch_req (next_TCB); 00124 } 00125 else { 00126 /* Check which task continues */ 00127 if (next_TCB->prio > os_tsk.run->prio) { 00128 /* preempt running task */ 00129 rt_put_rdy_first (os_tsk.run); 00130 os_tsk.run->state = READY; 00131 rt_switch_req (next_TCB); 00132 } 00133 else { 00134 /* put next task into ready list, no task switch takes place */ 00135 next_TCB->state = READY; 00136 rt_put_prio (&os_rdy, next_TCB); 00137 } 00138 } 00139 } 00140 00141 00142 /*--------------------------- rt_block --------------------------------------*/ 00143 00144 void rt_block (U16 timeout, U8 block_state) { 00145 /* Block running task and choose next ready task. */ 00146 /* "timeout" sets a time-out value or is 0xffff (=no time-out). */ 00147 /* "block_state" defines the appropriate task state */ 00148 P_TCB next_TCB; 00149 00150 if (timeout) { 00151 if (timeout < 0xffff) { 00152 rt_put_dly (os_tsk.run, timeout); 00153 } 00154 os_tsk.run->state = block_state; 00155 next_TCB = rt_get_first (&os_rdy); 00156 rt_switch_req (next_TCB); 00157 } 00158 } 00159 00160 00161 /*--------------------------- rt_tsk_pass -----------------------------------*/ 00162 00163 void rt_tsk_pass (void) { 00164 /* Allow tasks of same priority level to run cooperatively.*/ 00165 P_TCB p_new; 00166 00167 p_new = rt_get_same_rdy_prio(); 00168 if (p_new != NULL) { 00169 rt_put_prio ((P_XCB)&os_rdy, os_tsk.run); 00170 os_tsk.run->state = READY; 00171 rt_switch_req (p_new); 00172 } 00173 } 00174 00175 00176 /*--------------------------- rt_tsk_self -----------------------------------*/ 00177 00178 OS_TID rt_tsk_self (void) { 00179 /* Return own task identifier value. */ 00180 if (os_tsk.run == NULL) { 00181 return (0); 00182 } 00183 return (os_tsk.run->task_id); 00184 } 00185 00186 00187 /*--------------------------- rt_tsk_prio -----------------------------------*/ 00188 00189 OS_RESULT rt_tsk_prio (OS_TID task_id, U8 new_prio) { 00190 /* Change execution priority of a task to "new_prio". */ 00191 P_TCB p_task; 00192 00193 if (task_id == 0) { 00194 /* Change execution priority of calling task. */ 00195 os_tsk.run->prio = new_prio; 00196 run:if (rt_rdy_prio() > new_prio) { 00197 rt_put_prio (&os_rdy, os_tsk.run); 00198 os_tsk.run->state = READY; 00199 rt_dispatch (NULL); 00200 } 00201 return (OS_R_OK); 00202 } 00203 00204 /* Find the task in the "os_active_TCB" array. */ 00205 if (task_id > os_maxtaskrun || os_active_TCB[task_id-1] == NULL) { 00206 /* Task with "task_id" not found or not started. */ 00207 return (OS_R_NOK); 00208 } 00209 p_task = os_active_TCB[task_id-1]; 00210 p_task->prio = new_prio; 00211 if (p_task == os_tsk.run) { 00212 goto run; 00213 } 00214 rt_resort_prio (p_task); 00215 if (p_task->state == READY) { 00216 /* Task enqueued in a ready list. */ 00217 p_task = rt_get_first (&os_rdy); 00218 rt_dispatch (p_task); 00219 } 00220 return (OS_R_OK); 00221 } 00222 00223 /*--------------------------- rt_tsk_delete ---------------------------------*/ 00224 00225 OS_RESULT rt_tsk_delete (OS_TID task_id) { 00226 /* Terminate the task identified with "task_id". */ 00227 P_TCB task_context; 00228 00229 if (task_id == 0 || task_id == os_tsk.run->task_id) { 00230 /* Terminate itself. */ 00231 os_tsk.run->state = INACTIVE; 00232 os_tsk.run->tsk_stack = rt_get_PSP (); 00233 rt_stk_check (); 00234 os_active_TCB[os_tsk.run->task_id-1] = NULL; 00235 00236 os_tsk.run->stack = NULL; 00237 DBG_TASK_NOTIFY(os_tsk.run, __FALSE); 00238 os_tsk.run = NULL; 00239 rt_dispatch (NULL); 00240 /* The program should never come to this point. */ 00241 } 00242 else { 00243 /* Find the task in the "os_active_TCB" array. */ 00244 if (task_id > os_maxtaskrun || os_active_TCB[task_id-1] == NULL) { 00245 /* Task with "task_id" not found or not started. */ 00246 return (OS_R_NOK); 00247 } 00248 task_context = os_active_TCB[task_id-1]; 00249 rt_rmv_list (task_context); 00250 rt_rmv_dly (task_context); 00251 os_active_TCB[task_id-1] = NULL; 00252 00253 task_context->stack = NULL; 00254 DBG_TASK_NOTIFY(task_context, __FALSE); 00255 } 00256 return (OS_R_OK); 00257 } 00258 00259 00260 /*--------------------------- rt_sys_init -----------------------------------*/ 00261 00262 #ifdef __CMSIS_RTOS 00263 void rt_sys_init (void) { 00264 #else 00265 void rt_sys_init (FUNCP first_task, U32 prio_stksz, void *stk) { 00266 #endif 00267 /* Initialize system and start up task declared with "first_task". */ 00268 U32 i; 00269 00270 DBG_INIT(); 00271 00272 /* Initialize dynamic memory and task TCB pointers to NULL. */ 00273 for (i = 0; i < os_maxtaskrun; i++) { 00274 os_active_TCB[i] = NULL; 00275 } 00276 00277 /* Set up TCB of idle demon */ 00278 os_idle_TCB.task_id = 255; 00279 os_idle_TCB.priv_stack = idle_task_stack_size; 00280 os_idle_TCB.stack = idle_task_stack; 00281 rt_init_context (&os_idle_TCB, 0, os_idle_demon); 00282 00283 /* Set up ready list: initially empty */ 00284 os_rdy.cb_type = HCB; 00285 os_rdy.p_lnk = NULL; 00286 /* Set up delay list: initially empty */ 00287 os_dly.cb_type = HCB; 00288 os_dly.p_dlnk = NULL; 00289 os_dly.p_blnk = NULL; 00290 os_dly.delta_time = 0; 00291 00292 /* Fix SP and systemvariables to assume idle task is running */ 00293 /* Transform main program into idle task by assuming idle TCB */ 00294 #ifndef __CMSIS_RTOS 00295 rt_set_PSP (os_idle_TCB.tsk_stack+32); 00296 #endif 00297 os_tsk.run = &os_idle_TCB; 00298 os_tsk.run->state = RUNNING; 00299 00300 /* Initialize ps queue */ 00301 os_psq->first = 0; 00302 os_psq->last = 0; 00303 os_psq->size = os_fifo_size; 00304 00305 rt_init_robin (); 00306 00307 /* Intitialize SVC and PendSV */ 00308 rt_svc_init (); 00309 00310 #ifndef __CMSIS_RTOS 00311 /* Intitialize and start system clock timer */ 00312 os_tick_irqn = os_tick_init (); 00313 if (os_tick_irqn >= 0) { 00314 OS_X_INIT(os_tick_irqn); 00315 } 00316 00317 /* Start up first user task before entering the endless loop */ 00318 rt_tsk_create (first_task, prio_stksz, stk, NULL); 00319 #endif 00320 } 00321 00322 00323 /*--------------------------- rt_sys_start ----------------------------------*/ 00324 00325 #ifdef __CMSIS_RTOS 00326 void rt_sys_start (void) { 00327 /* Start system */ 00328 00329 /* Intitialize and start system clock timer */ 00330 os_tick_irqn = os_tick_init (); 00331 if (os_tick_irqn >= 0) { 00332 OS_X_INIT(os_tick_irqn); 00333 } 00334 } 00335 #endif 00336 00337 /*---------------------------------------------------------------------------- 00338 * end of file 00339 *---------------------------------------------------------------------------*/ 00340
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