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📄 os_sem.s79

📁 ARM仿真案例
💻 S79
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        CFI EndBlock cfiBlock2
        REQUIRE OSSemCreate
//   63 #endif    
//   64 
//   65 /*$PAGE*/
//   66 /*
//   67 *********************************************************************************************************
//   68 *                                           CREATE A SEMAPHORE
//   69 *
//   70 * Description: This function creates a semaphore.
//   71 *
//   72 * Arguments  : cnt           is the initial value for the semaphore.  If the value is 0, no resource is
//   73 *                            available (or no event has occurred).  You initialize the semaphore to a
//   74 *                            non-zero value to specify how many resources are available (e.g. if you have
//   75 *                            10 resources, you would initialize the semaphore to 10).
//   76 *
//   77 * Returns    : != (void *)0  is a pointer to the event control clock (OS_EVENT) associated with the
//   78 *                            created semaphore
//   79 *              == (void *)0  if no event control blocks were available
//   80 *********************************************************************************************************
//   81 */
//   82 

        RSEG CODE:CODE:NOROOT(2)
        CFI Block cfiBlock3 Using cfiCommon1
        CFI Function OSSemCreate
        THUMB
//   83 OS_EVENT  *OSSemCreate (INT16U cnt)
//   84 {
OSSemCreate:
        PUSH     {R4,R5,LR}
        CFI ?RET Frame(CFA, -4)
        CFI R5 Frame(CFA, -8)
        CFI R4 Frame(CFA, -12)
        CFI CFA R13+12
        MOVS     R4,R0
//   85 #if OS_CRITICAL_METHOD == 3                                /* Allocate storage for CPU status register */
//   86     OS_CPU_SR  cpu_sr;
//   87 #endif    
//   88     OS_EVENT  *pevent;
//   89 
//   90 
//   91     if (OSIntNesting > 0) {                                /* See if called from ISR ...               */
        LDR      R0,??DataTable7  ;; OSIntNesting
        LDRB     R0,[R0, #+0]
        CMP      R0,#+0
        BEQ      ??OSSemCreate_0
//   92         return ((OS_EVENT *)0);                            /* ... can't CREATE from an ISR             */
        MOVS     R0,#+0
        B        ??OSSemCreate_1
//   93     }
//   94     OS_ENTER_CRITICAL();
??OSSemCreate_0:
        _BLF     OS_CPU_SR_Save,??OS_CPU_SR_Save??rT
//   95     pevent = OSEventFreeList;                              /* Get next free event control block        */
        LDR      R1,??DataTable6  ;; OSEventFreeList
        LDR      R5,[R1, #+0]
//   96     if (OSEventFreeList != (OS_EVENT *)0) {                /* See if pool of free ECB pool was empty   */
        CMP      R5,#+0
        BEQ      ??OSSemCreate_2
//   97         OSEventFreeList = (OS_EVENT *)OSEventFreeList->OSEventPtr;
        LDR      R2,[R5, #+4]
        STR      R2,[R1, #+0]
//   98     }
//   99     OS_EXIT_CRITICAL();
??OSSemCreate_2:
        _BLF     OS_CPU_SR_Restore,??OS_CPU_SR_Restore??rT
//  100     if (pevent != (OS_EVENT *)0) {                         /* Get an event control block               */
        CMP      R5,#+0
        BEQ      ??OSSemCreate_3
//  101         pevent->OSEventType    = OS_EVENT_TYPE_SEM;
        MOVS     R0,#+3
        STRB     R0,[R5, #+0]
//  102         pevent->OSEventCnt     = cnt;                      /* Set semaphore value                      */
        STRH     R4,[R5, #+2]
//  103         pevent->OSEventPtr     = (void *)0;                /* Unlink from ECB free list                */
        MOVS     R0,#+0
        STR      R0,[R5, #+4]
//  104 #if OS_EVENT_NAME_SIZE > 1
//  105         pevent->OSEventName[0] = '?';                      /* Unknown name                             */
        MOVS     R0,#+63
        STRB     R0,[R5, #+16]
//  106         pevent->OSEventName[1] = OS_ASCII_NUL;
        MOVS     R0,#+0
        STRB     R0,[R5, #+17]
//  107 #endif
//  108         OS_EventWaitListInit(pevent);                      /* Initialize to 'nobody waiting' on sem.   */
        MOVS     R0,R5
        _BLF     OS_EventWaitListInit,??OS_EventWaitListInit??rT
//  109     }
//  110     return (pevent);
??OSSemCreate_3:
        MOVS     R0,R5
??OSSemCreate_1:
        POP      {R4,R5}
        POP      {R1}
        BX       R1               ;; return
        CFI EndBlock cfiBlock3
//  111 }

        RSEG CODE:CODE:NOROOT(2)
        CFI Block cfiBlock4 Using cfiCommon0
        CFI NoFunction
        ARM
??OSSemDel??rA:
        ADD      R12,PC,#+1
        BX       R12
        CFI EndBlock cfiBlock4
        REQUIRE OSSemDel
//  112 
//  113 /*$PAGE*/
//  114 /*
//  115 *********************************************************************************************************
//  116 *                                         DELETE A SEMAPHORE
//  117 *
//  118 * Description: This function deletes a semaphore and readies all tasks pending on the semaphore.
//  119 *
//  120 * Arguments  : pevent        is a pointer to the event control block associated with the desired
//  121 *                            semaphore.
//  122 *
//  123 *              opt           determines delete options as follows:
//  124 *                            opt == OS_DEL_NO_PEND   Delete semaphore ONLY if no task pending
//  125 *                            opt == OS_DEL_ALWAYS    Deletes the semaphore even if tasks are waiting.
//  126 *                                                    In this case, all the tasks pending will be readied.
//  127 *
//  128 *              err           is a pointer to an error code that can contain one of the following values:
//  129 *                            OS_NO_ERR               The call was successful and the semaphore was deleted
//  130 *                            OS_ERR_DEL_ISR          If you attempted to delete the semaphore from an ISR
//  131 *                            OS_ERR_INVALID_OPT      An invalid option was specified
//  132 *                            OS_ERR_TASK_WAITING     One or more tasks were waiting on the semaphore
//  133 *                            OS_ERR_EVENT_TYPE       If you didn't pass a pointer to a semaphore
//  134 *                            OS_ERR_PEVENT_NULL      If 'pevent' is a NULL pointer.
//  135 *
//  136 * Returns    : pevent        upon error
//  137 *              (OS_EVENT *)0 if the semaphore was successfully deleted.
//  138 *
//  139 * Note(s)    : 1) This function must be used with care.  Tasks that would normally expect the presence of
//  140 *                 the semaphore MUST check the return code of OSSemPend().
//  141 *              2) OSSemAccept() callers will not know that the intended semaphore has been deleted unless
//  142 *                 they check 'pevent' to see that it's a NULL pointer.
//  143 *              3) This call can potentially disable interrupts for a long time.  The interrupt disable
//  144 *                 time is directly proportional to the number of tasks waiting on the semaphore.
//  145 *              4) Because ALL tasks pending on the semaphore will be readied, you MUST be careful in
//  146 *                 applications where the semaphore is used for mutual exclusion because the resource(s)
//  147 *                 will no longer be guarded by the semaphore.
//  148 *********************************************************************************************************
//  149 */
//  150 
//  151 #if OS_SEM_DEL_EN > 0

        RSEG CODE:CODE:NOROOT(2)
        CFI Block cfiBlock5 Using cfiCommon1
        CFI Function OSSemDel
        THUMB
//  152 OS_EVENT  *OSSemDel (OS_EVENT *pevent, INT8U opt, INT8U *err)
//  153 {
OSSemDel:
        PUSH     {R1,R4-R7,LR}
        CFI ?RET Frame(CFA, -4)
        CFI R7 Frame(CFA, -8)
        CFI R6 Frame(CFA, -12)
        CFI R5 Frame(CFA, -16)
        CFI R4 Frame(CFA, -20)
        CFI CFA R13+24
        MOVS     R4,R0
        MOVS     R5,R2
//  154 #if OS_CRITICAL_METHOD == 3                                /* Allocate storage for CPU status register */
//  155     OS_CPU_SR  cpu_sr;
//  156 #endif    
//  157     BOOLEAN    tasks_waiting;
//  158 
//  159 
//  160     if (OSIntNesting > 0) {                                /* See if called from ISR ...               */
        LDR      R0,??DataTable7  ;; OSIntNesting
        LDRB     R0,[R0, #+0]
        CMP      R0,#+0
        BEQ      ??OSSemDel_0
//  161         *err = OS_ERR_DEL_ISR;                             /* ... can't DELETE from an ISR             */
        MOVS     R0,#+140
        B.N      ??OSSemDel_1
//  162         return (pevent);
//  163     }
//  164 #if OS_ARG_CHK_EN > 0
//  165     if (pevent == (OS_EVENT *)0) {                         /* Validate 'pevent'                        */
??OSSemDel_0:
        CMP      R4,#+0
        BNE      ??OSSemDel_2
//  166         *err = OS_ERR_PEVENT_NULL;
        MOVS     R0,#+4
        STRB     R0,[R5, #+0]
//  167         return (pevent);
        MOVS     R0,#+0
        B        ??OSSemDel_3
//  168     }
//  169 #endif
//  170     if (pevent->OSEventType != OS_EVENT_TYPE_SEM) {        /* Validate event block type                */
??OSSemDel_2:
        LDRB     R0,[R4, #+0]
        CMP      R0,#+3
        BEQ      ??OSSemDel_4
//  171         *err = OS_ERR_EVENT_TYPE;
        MOVS     R0,#+1
        B.N      ??OSSemDel_1
//  172         return (pevent);
//  173     }
//  174     OS_ENTER_CRITICAL();
??OSSemDel_4:
        _BLF     OS_CPU_SR_Save,??OS_CPU_SR_Save??rT
        MOVS     R6,R0
//  175     if (pevent->OSEventGrp != 0x00) {                      /* See if any tasks waiting on semaphore    */
        LDRB     R0,[R4, #+1]
        CMP      R0,#+0
        BEQ      ??OSSemDel_5
//  176         tasks_waiting = TRUE;                              /* Yes                                      */
        MOVS     R7,#+1
        B        ??OSSemDel_6
//  177     } else {
//  178         tasks_waiting = FALSE;                             /* No                                       */
??OSSemDel_5:
        MOVS     R7,#+0
//  179     }
//  180     switch (opt) {
??OSSemDel_6:
        MOV      R0,SP
        LDRB     R0,[R0, #+0]
        CMP      R0,#+0
        BEQ      ??OSSemDel_7
        CMP      R0,#+1
        BEQ      ??OSSemDel_8
        B        ??OSSemDel_9
//  181         case OS_DEL_NO_PEND:                               /* Delete semaphore only if no task waiting */
//  182              if (tasks_waiting == FALSE) {
??OSSemDel_7:
        CMP      R7,#+0
        BNE      ??OSSemDel_10
//  183 #if OS_EVENT_NAME_SIZE > 1
//  184                  pevent->OSEventName[0] = '?';             /* Unknown name                             */
        MOVS     R0,#+63
        STRB     R0,[R4, #+16]
//  185                  pevent->OSEventName[1] = OS_ASCII_NUL;
        MOVS     R0,#+0
        STRB     R0,[R4, #+17]
//  186 #endif
//  187                  pevent->OSEventType    = OS_EVENT_TYPE_UNUSED;
        STRB     R0,[R4, #+0]
//  188                  pevent->OSEventPtr     = OSEventFreeList; /* Return Event Control Block to free list  */
        LDR      R0,??DataTable6  ;; OSEventFreeList
        LDR      R0,[R0, #+0]
        STR      R0,[R4, #+4]
//  189                  pevent->OSEventCnt     = 0;
        MOVS     R0,#+0
        STRH     R0,[R4, #+2]
//  190                  OSEventFreeList        = pevent;          /* Get next free event control block        */
        LDR      R0,??DataTable6  ;; OSEventFreeList
        STR      R4,[R0, #+0]
//  191                  OS_EXIT_CRITICAL();
        MOVS     R0,R6
        _BLF     OS_CPU_SR_Restore,??OS_CPU_SR_Restore??rT
//  192                  *err                   = OS_NO_ERR;
??OSSemDel_11:
        MOVS     R0,#+0
        STRB     R0,[R5, #+0]
//  193                  return ((OS_EVENT *)0);                   /* Semaphore has been deleted               */
        B        ??OSSemDel_3
//  194              } else {
//  195                  OS_EXIT_CRITICAL();
??OSSemDel_10:
        MOVS     R0,R6
        _BLF     OS_CPU_SR_Restore,??OS_CPU_SR_Restore??rT
//  196                  *err                   = OS_ERR_TASK_WAITING;
        MOVS     R0,#+8
        B.N      ??OSSemDel_1
//  197                  return (pevent);
//  198              }
//  199 
//  200         case OS_DEL_ALWAYS:                                /* Always delete the semaphore              */
//  201              while (pevent->OSEventGrp != 0x00) {          /* Ready ALL tasks waiting for semaphore    */
//  202                  OS_EventTaskRdy(pevent, (void *)0, OS_STAT_SEM);
??OSSemDel_12:
        MOVS     R2,#+1
        MOVS     R1,#+0
        MOVS     R0,R4
        _BLF     OS_EventTaskRdy,??OS_EventTaskRdy??rT
//  203              }
??OSSemDel_8:
        LDRB     R0,[R4, #+1]
        CMP      R0,#+0
        BNE      ??OSSemDel_12
//  204 #if OS_EVENT_NAME_SIZE > 1
//  205              pevent->OSEventName[0] = '?';                 /* Unknown name                             */
        MOVS     R0,#+63
        STRB     R0,[R4, #+16]
//  206              pevent->OSEventName[1] = OS_ASCII_NUL;
        MOVS     R0,#+0
        STRB     R0,[R4, #+17]
//  207 #endif
//  208              pevent->OSEventType    = OS_EVENT_TYPE_UNUSED;
        STRB     R0,[R4, #+0]

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