hi_memmap.c

华为 HI3510 BOOTLOADER HIBOOT 源码包

/************************************************************/
/* file name : memmap.c                                     */
/* linux /dev/mem mmap support func							*/
/* 															*/
/* 															*/
/* Copyright 2005 huawei com.                               */
/* Author :zhouaidi(42136)									*/
/* Create date: 2005-04-07									*/
/* Modify history											*/
/* 2005-06-12: 对映射成功空间建立管理链表，可以防止对重叠   */
/*             空间的重复映射                               */
/************************************************************/

#include <config.h>

#if defined(CONFIG_HI3510_LOGO)


/*#include <stdio.h>*/

#include "hi_common/hi.h"
#include "hi_inc.h"

#ifdef OS_LINUX
#include <fcntl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/mman.h>

typedef struct tag_MMAP_Node
{
	unsigned int Start_P;
	unsigned int Start_V;
	unsigned int length;
	struct tag_MMAP_Node * next;
}MMAP_Node_t;

MMAP_Node_t * pMMAPNode = NULL;

#define PAGE_SIZE 0x1000
#define PAGE_SIZE_MASK 0xfffff000

static int fd = -1;
static const char dev[]="/dev/mem";

#endif


/* no need considering page_size of 4K */
void * memmap(unsigned int phy_addr, unsigned int size)
{
#ifndef OS_LINUX
	return (void *)phy_addr;
#else
	unsigned int phy_addr_in_page;
	unsigned int page_diff;

	unsigned int size_in_page;
	unsigned int size_diff;

	MMAP_Node_t * pTmp;
	MMAP_Node_t * pNew;
	
	void *addr=NULL;

	if(size == 0)
	{
		printf("memmap(): size can't be zero!\n");
		return NULL;
	}

	/* check if the physical memory space have been mmaped */
	pTmp = pMMAPNode;
	while(pTmp != NULL)
	{
		if( (phy_addr >= pTmp->Start_P) && 
			( (phy_addr + size) <= (pTmp->Start_P + pTmp->length) ) )
		{
			return (void *)(pTmp->Start_V + phy_addr - pTmp->Start_P);
		}

		pTmp = pTmp->next;
	}

	/* not mmaped yet */
	if(fd < 0)
	{
		/* dev not opened yet, so open it */
		fd = open (dev, O_RDWR);
		//printf("fd=%d\n", fd);
		if (fd < 0)
		{
			printf("open %s error!\n", dev);
			return NULL;
		}
	}

	/* addr align in page_size(4K) */
	phy_addr_in_page = phy_addr & PAGE_SIZE_MASK;
	page_diff = phy_addr - phy_addr_in_page;

	/* size in page_size */
	size_in_page =((size + page_diff - 1) & PAGE_SIZE_MASK) + PAGE_SIZE;

	addr = mmap ((void *)0, size_in_page, PROT_READ|PROT_WRITE, MAP_SHARED, fd, phy_addr_in_page);
	if (addr == MAP_FAILED)
	{
		printf("mmap @ 0x%x error!\n", phy_addr_in_page);
		return NULL;
	}
	printf("Mapped %s (%lu @ %lx) at 0x%x\n", dev, size_in_page, phy_addr_in_page, addr);

	/* add this mmap to MMAP Node */
	pNew = (MMAP_Node_t *)malloc(sizeof(MMAP_Node_t));
	pNew->Start_P = phy_addr_in_page;
	pNew->Start_V = (unsigned int)addr;
	pNew->length = size_in_page;
	pNew->next = NULL;
	
	if(pMMAPNode == NULL)
	{
		pMMAPNode = pNew;
	}
	else
	{
		pTmp = pMMAPNode;
		while(pTmp->next != NULL)
		{
			pTmp = pTmp->next;
		}

		pTmp->next = pNew;
	}

	return (void *)(addr+page_diff);
#endif
}

#endif