155 lines
5.0 KiB
C
Executable File
155 lines
5.0 KiB
C
Executable File
/*
|
|
**********************************************************************************************************************
|
|
* eGon
|
|
* the Embedded GO-ON Bootloader System
|
|
* eGON memory sub-system
|
|
*
|
|
* Copyright(C), 2006-2010, SoftWinners Microelectronic Co., Ltd.
|
|
* All Rights Reserved
|
|
*
|
|
* File : mem_alloc
|
|
*
|
|
* By : Jerry
|
|
*
|
|
* Version : V2.00
|
|
*
|
|
* Date :
|
|
*
|
|
* Descript:
|
|
**********************************************************************************************************************
|
|
*/
|
|
#include <common.h>
|
|
|
|
struct alloc_struct_t
|
|
{
|
|
uint address; //申请内存的地址
|
|
uint size; //分配的内存大小，用户实际得到的内存大小
|
|
uint o_size; //用户申请的内存大小
|
|
struct alloc_struct_t *next;
|
|
};
|
|
|
|
#define MY_BYTE_ALIGN(x) ( ( (x + 31) >> 5) << 5) /* alloc based on 1k byte */
|
|
|
|
static struct alloc_struct_t boot_heap_head, boot_heap_tail;
|
|
|
|
|
|
/*
|
|
*********************************************************************************************************
|
|
* CREATE HEAP
|
|
*
|
|
* Description: create heap.
|
|
*
|
|
* Aguments : pHeapHead heap start address.
|
|
* nHeapSize heap size.
|
|
*
|
|
* Returns : EPDK_OK/EPDK_FAIL.
|
|
*********************************************************************************************************
|
|
*/
|
|
|
|
void mem_malloc_init(ulong pHeapHead, ulong nHeapSize)
|
|
{
|
|
if(pHeapHead <0x40000000) return ; //检查Head地址是否合法
|
|
|
|
boot_heap_head.size = boot_heap_tail.size = 0;
|
|
boot_heap_head.address = pHeapHead;
|
|
boot_heap_tail.address = pHeapHead + nHeapSize;
|
|
boot_heap_head.next = &boot_heap_tail;
|
|
boot_heap_tail.next = 0;
|
|
|
|
return ;
|
|
}
|
|
|
|
/*
|
|
*********************************************************************************************************
|
|
* MALLOC BUFFER FROM HEAP
|
|
*
|
|
* Description: malloc a buffer from heap.
|
|
*
|
|
* Aguments : num_bytes the size of the buffer need malloc;
|
|
*
|
|
* Returns : the po__s32er to buffer has malloc.
|
|
*********************************************************************************************************
|
|
*/
|
|
void *malloc(ulong num_bytes)
|
|
{
|
|
struct alloc_struct_t *ptr, *newptr;
|
|
uint actual_bytes;
|
|
|
|
if (!num_bytes) return NULL;
|
|
|
|
actual_bytes = MY_BYTE_ALIGN(num_bytes); /* translate the byte count to size of long type */
|
|
|
|
ptr = &boot_heap_head; /* scan from the boot_heap_head of the heap */
|
|
|
|
while (ptr && ptr->next) /* look for enough memory for alloc */
|
|
{
|
|
if (ptr->next->address >= (ptr->address + ptr->size + \
|
|
2 * sizeof(struct alloc_struct_t) + actual_bytes))
|
|
{
|
|
break;
|
|
}
|
|
/* find enough memory to alloc */
|
|
ptr = ptr->next;
|
|
}
|
|
|
|
if (!ptr->next)
|
|
{
|
|
return 0; /* it has reached the boot_heap_tail of the heap now */
|
|
}
|
|
|
|
newptr = (struct alloc_struct_t *)(ptr->address + ptr->size);
|
|
/* create a new node for the memory block */
|
|
if (!newptr)
|
|
{
|
|
return 0; /* create the node failed, can't manage the block */
|
|
}
|
|
|
|
/* set the memory block chain, insert the node to the chain */
|
|
newptr->address = ptr->address + ptr->size + sizeof(struct alloc_struct_t);
|
|
newptr->size = actual_bytes;
|
|
newptr->o_size = num_bytes;
|
|
newptr->next = ptr->next;
|
|
ptr->next = newptr;
|
|
|
|
return (void *)newptr->address;
|
|
}
|
|
|
|
/*
|
|
*********************************************************************************************************
|
|
* FREE BUFFER TO HEAP
|
|
*
|
|
* Description: free buffer to heap
|
|
*
|
|
* Aguments : p the po__s32er to the buffer which need be free.
|
|
*
|
|
* Returns : none
|
|
*********************************************************************************************************
|
|
*/
|
|
void free(void *p)
|
|
{
|
|
struct alloc_struct_t *ptr, *prev;
|
|
|
|
if( p == NULL )
|
|
return;
|
|
|
|
ptr = &boot_heap_head; /* look for the node which po__s32 this memory block */
|
|
while (ptr && ptr->next)
|
|
{
|
|
if (ptr->next->address == (uint)p)
|
|
break; /* find the node which need to be release */
|
|
ptr = ptr->next;
|
|
}
|
|
|
|
prev = ptr;
|
|
ptr = ptr->next;
|
|
|
|
if (!ptr) return; /* the node is heap boot_heap_tail */
|
|
|
|
prev->next = ptr->next; /* delete the node which need be released from the memory block chain */
|
|
|
|
return ;
|
|
}
|
|
|
|
|
|
/* end of mem_alloc.c */
|