init.c

来源于外国的开源rtos,用于小型mcu,支持优先级抢占调度

/*
 *  Copyright (c) 2004, Jun Li, [e-mail].
 *  All rights reserved. 
 *
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions
 *  are met:
 *
 *   1. Redistributions of source code must retain the above copyright
 *      notice, this list of conditions and the following disclaimer.
 *   2. Redistributions in binary form must reproduce the above copyright
 *      notice, this list of conditions and the following disclaimer in the
 *      documentation and/or other materials provided with the distribution.
 *   3. The name of the author may not be used to endorse or promote
 *      products derived from this software without specific prior written
 *      permission. 
 *
 *  THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
 *  OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 *  WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 *  ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
 *  INDIRECT,  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 *  (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 *  SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 *  HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 *  STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 *  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 *  OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */

#include <stdlib.h>
#include "types.h"
#include "mem.h"
#include "interrupt.h"
#include "../../../inc/picoos.h"

unsigned int        _osFreeMemAddr; /* this can be accessed from outside */
static mempool_t    systemHeapMemory;

extern void main(void);

#define ARM_MEM_ALIGN(x)        (((unsigned int)x + 3) & 0xfffffffcUL)


void *osHeapAlloc(u_int size)
{
    return mempool_alloc(&systemHeapMemory, (unsigned)size);
}


void osHeapFree(void *ptr)
{
    if (ptr) 
        mempool_free(&systemHeapMemory, ptr);
}


int osInit(void *free_mem_start, u_int heap_size)
{
    _osFreeMemAddr = ARM_MEM_ALIGN(free_mem_start);

    mempool_create(&systemHeapMemory, (char *)_osFreeMemAddr, heap_size);
    _osFreeMemAddr += ARM_MEM_ALIGN(heap_size);

    return TRUE;
}


void C_Entry(void *memstart)
{
    osInterruptInitialize();

    osInit(memstart, HEAP_MEMORY_SIZE);

    main();
}