tool/mbed/mbed-sdk/libraries/rtos/rtx/TARGET_CORTEX_A/rt_Mailbox.c

   1 /*----------------------------------------------------------------------------
   2  *      RL-ARM - RTX
   3  *----------------------------------------------------------------------------
   4  *      Name:    RT_MAILBOX.C
   5  *      Purpose: Implements waits and wake-ups for mailbox messages
   6  *      Rev.:    V4.60
   7  *----------------------------------------------------------------------------
   8  *
   9  * Copyright (c) 1999-2009 KEIL, 2009-2012 ARM Germany GmbH
  10  * All rights reserved.
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions are met:
  13  *  - Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  *  - Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  *  - Neither the name of ARM  nor the names of its contributors may be used
  19  *    to endorse or promote products derived from this software without
  20  *    specific prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  23  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  25  * ARE DISCLAIMED. IN NO EVENT SHALL COPYRIGHT HOLDERS AND CONTRIBUTORS BE
  26  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  27  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  28  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  29  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  30  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  31  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  32  * POSSIBILITY OF SUCH DAMAGE.
  33  *---------------------------------------------------------------------------*/
  34
  35 #include "rt_TypeDef.h"
  36 #include "RTX_Config.h"
  37 #include "rt_System.h"
  38 #include "rt_List.h"
  39 #include "rt_Mailbox.h"
  40 #include "rt_MemBox.h"
  41 #include "rt_Task.h"
  42 #ifdef __CORTEX_A9
  43 #include "rt_HAL_CA.h"
  44 #else
  45 #include "rt_HAL_CM.h"
  46 #endif
  47
  48
  49 /*----------------------------------------------------------------------------
  50  *      Functions
  51  *---------------------------------------------------------------------------*/
  52
  53
  54 /*--------------------------- rt_mbx_init -----------------------------------*/
  55
  56 void rt_mbx_init (OS_ID mailbox, U16 mbx_size) {
  57   /* Initialize a mailbox */
  58   P_MCB p_MCB = mailbox;
  59
  60   p_MCB->cb_type = MCB;
  61   p_MCB->state   = 0;
  62   p_MCB->isr_st  = 0;
  63   p_MCB->p_lnk   = NULL;
  64   p_MCB->first   = 0;
  65   p_MCB->last    = 0;
  66   p_MCB->count   = 0;
  67   p_MCB->size    = (mbx_size + sizeof(void *) - sizeof(struct OS_MCB)) /
  68                                                      (U32)sizeof (void *);
  69 }
  70
  71
  72 /*--------------------------- rt_mbx_send -----------------------------------*/
  73
  74 OS_RESULT rt_mbx_send (OS_ID mailbox, void *p_msg, U16 timeout) {
  75   /* Send message to a mailbox */
  76   P_MCB p_MCB = mailbox;
  77   P_TCB p_TCB;
  78
  79   if ((p_MCB->p_lnk != NULL) && (p_MCB->state == 1)) {
  80     /* A task is waiting for message */
  81     p_TCB = rt_get_first ((P_XCB)p_MCB);
  82 #ifdef __CMSIS_RTOS
  83     rt_ret_val2(p_TCB, 0x10/*osEventMessage*/, (U32)p_msg);
  84 #else
  85     *p_TCB->msg = p_msg;
  86     rt_ret_val (p_TCB, OS_R_MBX);
  87 #endif
  88     rt_rmv_dly (p_TCB);
  89     rt_dispatch (p_TCB);
  90   }
  91   else {
  92     /* Store message in mailbox queue */
  93     if (p_MCB->count == p_MCB->size) {
  94       /* No free message entry, wait for one. If message queue is full, */
  95       /* then no task is waiting for message. The 'p_MCB->p_lnk' list   */
  96       /* pointer can now be reused for send message waits task list.    */
  97       if (timeout == 0) {
  98         return (OS_R_TMO);
  99       }
 100       if (p_MCB->p_lnk != NULL) {
 101         rt_put_prio ((P_XCB)p_MCB, os_tsk.run);
 102       }
 103       else {
 104         p_MCB->p_lnk = os_tsk.run;
 105         os_tsk.run->p_lnk  = NULL;
 106         os_tsk.run->p_rlnk = (P_TCB)p_MCB;
 107         /* Task is waiting to send a message */
 108         p_MCB->state = 2;
 109       }
 110       os_tsk.run->msg = p_msg;
 111       rt_block (timeout, WAIT_MBX);
 112       return (OS_R_TMO);
 113     }
 114     /* Yes, there is a free entry in a mailbox. */
 115     p_MCB->msg[p_MCB->first] = p_msg;
 116     rt_inc (&p_MCB->count);
 117     if (++p_MCB->first == p_MCB->size) {
 118       p_MCB->first = 0;
 119     }
 120   }
 121   return (OS_R_OK);
 122 }
 123
 124
 125 /*--------------------------- rt_mbx_wait -----------------------------------*/
 126
 127 OS_RESULT rt_mbx_wait (OS_ID mailbox, void **message, U16 timeout) {
 128   /* Receive a message; possibly wait for it */
 129   P_MCB p_MCB = mailbox;
 130   P_TCB p_TCB;
 131
 132   /* If a message is available in the fifo buffer */
 133   /* remove it from the fifo buffer and return. */
 134   if (p_MCB->count) {
 135     *message = p_MCB->msg[p_MCB->last];
 136     if (++p_MCB->last == p_MCB->size) {
 137       p_MCB->last = 0;
 138     }
 139     if ((p_MCB->p_lnk != NULL) && (p_MCB->state == 2)) {
 140       /* A task is waiting to send message */
 141       p_TCB = rt_get_first ((P_XCB)p_MCB);
 142 #ifdef __CMSIS_RTOS
 143       rt_ret_val(p_TCB, 0/*osOK*/);
 144 #else
 145       rt_ret_val(p_TCB, OS_R_OK);
 146 #endif
 147       p_MCB->msg[p_MCB->first] = p_TCB->msg;
 148       if (++p_MCB->first == p_MCB->size) {
 149         p_MCB->first = 0;
 150       }
 151       rt_rmv_dly (p_TCB);
 152       rt_dispatch (p_TCB);
 153     }
 154     else {
 155       rt_dec (&p_MCB->count);
 156     }
 157     return (OS_R_OK);
 158   }
 159   /* No message available: wait for one */
 160   if (timeout == 0) {
 161     return (OS_R_TMO);
 162   }
 163   if (p_MCB->p_lnk != NULL) {
 164     rt_put_prio ((P_XCB)p_MCB, os_tsk.run);
 165   }
 166   else {
 167     p_MCB->p_lnk = os_tsk.run;
 168     os_tsk.run->p_lnk = NULL;
 169     os_tsk.run->p_rlnk = (P_TCB)p_MCB;
 170     /* Task is waiting to receive a message */
 171     p_MCB->state = 1;
 172   }
 173   rt_block(timeout, WAIT_MBX);
 174 #ifndef __CMSIS_RTOS
 175   os_tsk.run->msg = message;
 176 #endif
 177   return (OS_R_TMO);
 178 }
 179
 180
 181 /*--------------------------- rt_mbx_check ----------------------------------*/
 182
 183 OS_RESULT rt_mbx_check (OS_ID mailbox) {
 184   /* Check for free space in a mailbox. Returns the number of messages     */
 185   /* that can be stored to a mailbox. It returns 0 when mailbox is full.   */
 186   P_MCB p_MCB = mailbox;
 187
 188   return (p_MCB->size - p_MCB->count);
 189 }
 190
 191
 192 /*--------------------------- isr_mbx_send ----------------------------------*/
 193
 194 void isr_mbx_send (OS_ID mailbox, void *p_msg) {
 195   /* Same function as "os_mbx_send", but to be called by ISRs. */
 196   P_MCB p_MCB = mailbox;
 197
 198   rt_psq_enq (p_MCB, (U32)p_msg);
 199   rt_psh_req ();
 200 }
 201
 202
 203 /*--------------------------- isr_mbx_receive -------------------------------*/
 204
 205 OS_RESULT isr_mbx_receive (OS_ID mailbox, void **message) {
 206   /* Receive a message in the interrupt function. The interrupt function   */
 207   /* should not wait for a message since this would block the rtx os.      */
 208   P_MCB p_MCB = mailbox;
 209
 210   if (p_MCB->count) {
 211     /* A message is available in the fifo buffer. */
 212     *message = p_MCB->msg[p_MCB->last];
 213     if (p_MCB->state == 2) {
 214       /* A task is locked waiting to send message */
 215       rt_psq_enq (p_MCB, 0);
 216       rt_psh_req ();
 217     }
 218     rt_dec (&p_MCB->count);
 219     if (++p_MCB->last == p_MCB->size) {
 220       p_MCB->last = 0;
 221     }
 222     return (OS_R_MBX);
 223   }
 224   return (OS_R_OK);
 225 }
 226
 227
 228 /*--------------------------- rt_mbx_psh ------------------------------------*/
 229
 230 void rt_mbx_psh (P_MCB p_CB, void *p_msg) {
 231   /* Store the message to the mailbox queue or pass it to task directly. */
 232   P_TCB p_TCB;
 233   void *mem;
 234
 235   if (p_CB->p_lnk != NULL) switch (p_CB->state) {
 236 #ifdef __CMSIS_RTOS
 237     case 3:
 238       /* Task is waiting to allocate memory, remove it from the waiting list */
 239       mem = rt_alloc_box(p_msg);
 240       if (mem == NULL) break;
 241       p_TCB = rt_get_first ((P_XCB)p_CB);
 242       rt_ret_val(p_TCB, (U32)mem);
 243       p_TCB->state = READY;
 244       rt_rmv_dly (p_TCB);
 245       rt_put_prio (&os_rdy, p_TCB);
 246       break;
 247 #endif
 248     case 2:
 249       /* Task is waiting to send a message, remove it from the waiting list */
 250       p_TCB = rt_get_first ((P_XCB)p_CB);
 251 #ifdef __CMSIS_RTOS
 252       rt_ret_val(p_TCB, 0/*osOK*/);
 253 #else
 254       rt_ret_val(p_TCB, OS_R_OK);
 255 #endif
 256       p_CB->msg[p_CB->first] = p_TCB->msg;
 257       rt_inc (&p_CB->count);
 258       if (++p_CB->first == p_CB->size) {
 259         p_CB->first = 0;
 260       }
 261       p_TCB->state = READY;
 262       rt_rmv_dly (p_TCB);
 263       rt_put_prio (&os_rdy, p_TCB);
 264       break;
 265     case 1:
 266       /* Task is waiting for a message, pass the message to the task directly */
 267       p_TCB = rt_get_first ((P_XCB)p_CB);
 268 #ifdef __CMSIS_RTOS
 269       rt_ret_val2(p_TCB, 0x10/*osEventMessage*/, (U32)p_msg);
 270 #else
 271       *p_TCB->msg = p_msg;
 272       rt_ret_val (p_TCB, OS_R_MBX);
 273 #endif
 274       p_TCB->state = READY;
 275       rt_rmv_dly (p_TCB);
 276       rt_put_prio (&os_rdy, p_TCB);
 277       break;
 278   } else {
 279     /* No task is waiting for a message, store it to the mailbox queue */
 280     if (p_CB->count < p_CB->size) {
 281       p_CB->msg[p_CB->first] = p_msg;
 282       rt_inc (&p_CB->count);
 283       if (++p_CB->first == p_CB->size) {
 284         p_CB->first = 0;
 285       }
 286     }
 287     else {
 288       os_error (OS_ERR_MBX_OVF);
 289     }
 290   }
 291 }
 292
 293 /*----------------------------------------------------------------------------
 294  * end of file
 295  *---------------------------------------------------------------------------*/
 296