tmk_core/tool/mbed/mbed-sdk/libraries/rtos/rtx/TARGET_CORTEX_M/rt_MemBox.c

   1 /*----------------------------------------------------------------------------
   2  *      RL-ARM - RTX
   3  *----------------------------------------------------------------------------
   4  *      Name:    RT_MEMBOX.C
   5  *      Purpose: Interface functions for fixed memory block management system
   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_Conf.h"
  37 #include "rt_System.h"
  38 #include "rt_MemBox.h"
  39 #include "rt_HAL_CM.h"
  40
  41 /*----------------------------------------------------------------------------
  42  *      Global Functions
  43  *---------------------------------------------------------------------------*/
  44
  45
  46 /*--------------------------- _init_box -------------------------------------*/
  47
  48 int _init_box  (void *box_mem, U32 box_size, U32 blk_size) {
  49   /* Initialize memory block system, returns 0 if OK, 1 if fails. */
  50   void *end;
  51   void *blk;
  52   void *next;
  53   U32  sizeof_bm;
  54
  55   /* Create memory structure. */
  56   if (blk_size & BOX_ALIGN_8) {
  57     /* Memory blocks 8-byte aligned. */
  58     blk_size = ((blk_size & ~BOX_ALIGN_8) + 7) & ~7;
  59     sizeof_bm = (sizeof (struct OS_BM) + 7) & ~7;
  60   }
  61   else {
  62     /* Memory blocks 4-byte aligned. */
  63     blk_size = (blk_size + 3) & ~3;
  64     sizeof_bm = sizeof (struct OS_BM);
  65   }
  66   if (blk_size == 0) {
  67     return (1);
  68   }
  69   if ((blk_size + sizeof_bm) > box_size) {
  70     return (1);
  71   }
  72   /* Create a Memory structure. */
  73   blk = ((U8 *) box_mem) + sizeof_bm;
  74   ((P_BM) box_mem)->free = blk;
  75   end = ((U8 *) box_mem) + box_size;
  76   ((P_BM) box_mem)->end      = end;
  77   ((P_BM) box_mem)->blk_size = blk_size;
  78
  79   /* Link all free blocks using offsets. */
  80   end = ((U8 *) end) - blk_size;
  81   while (1)  {
  82     next = ((U8 *) blk) + blk_size;
  83     if (next > end)  break;
  84     *((void **)blk) = next;
  85     blk = next;
  86   }
  87   /* end marker */
  88   *((void **)blk) = 0;
  89   return (0);
  90 }
  91
  92 /*--------------------------- rt_alloc_box ----------------------------------*/
  93
  94 void *rt_alloc_box (void *box_mem) {
  95   /* Allocate a memory block and return start address. */
  96   void **free;
  97 #ifndef __USE_EXCLUSIVE_ACCESS
  98   int  irq_dis;
  99
 100   irq_dis = __disable_irq ();
 101   free = ((P_BM) box_mem)->free;
 102   if (free) {
 103     ((P_BM) box_mem)->free = *free;
 104   }
 105   if (!irq_dis) __enable_irq ();
 106 #else
 107   do {
 108     if ((free = (void **)__ldrex(&((P_BM) box_mem)->free)) == 0) {
 109       __clrex();
 110       break;
 111     }
 112   } while (__strex((U32)*free, &((P_BM) box_mem)->free));
 113 #endif
 114   return (free);
 115 }
 116
 117
 118 /*--------------------------- _calloc_box -----------------------------------*/
 119
 120 void *_calloc_box (void *box_mem)  {
 121   /* Allocate a 0-initialized memory block and return start address. */
 122   void *free;
 123   U32 *p;
 124   U32 i;
 125
 126   free = _alloc_box (box_mem);
 127   if (free)  {
 128     p = free;
 129     for (i = ((P_BM) box_mem)->blk_size; i; i -= 4)  {
 130       *p = 0;
 131       p++;
 132     }
 133   }
 134   return (free);
 135 }
 136
 137
 138 /*--------------------------- rt_free_box -----------------------------------*/
 139
 140 int rt_free_box (void *box_mem, void *box) {
 141   /* Free a memory block, returns 0 if OK, 1 if box does not belong to box_mem */
 142 #ifndef __USE_EXCLUSIVE_ACCESS
 143   int irq_dis;
 144 #endif
 145
 146   if (box < box_mem || box >= ((P_BM) box_mem)->end) {
 147     return (1);
 148   }
 149
 150 #ifndef __USE_EXCLUSIVE_ACCESS
 151   irq_dis = __disable_irq ();
 152   *((void **)box) = ((P_BM) box_mem)->free;
 153   ((P_BM) box_mem)->free = box;
 154   if (!irq_dis) __enable_irq ();
 155 #else
 156   do {
 157     *((void **)box) = (void *)__ldrex(&((P_BM) box_mem)->free);
 158   } while (__strex ((U32)box, &((P_BM) box_mem)->free));
 159 #endif
 160   return (0);
 161 }
 162
 163 /*----------------------------------------------------------------------------
 164  * end of file
 165  *---------------------------------------------------------------------------*/
 166