#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <fcntl.h>
#include <sys/mman.h>
#include <stdlib.h>
#include <stdint.h>
#include <errno.h>
#include <fcntl.h>
#include <string.h>
#include <sys/time.h>   //      gettimeofday
#include <sys/stat.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/mman.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>

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


#define DEFAULT_MD_LEN 4096
int fd=-1;
static const char dev[]="/dev/mem";

#define PAGE_SIZE 0x1000
#define PAGE_SIZE_MASK 0xfffff000


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

TMMAP_Node_t * pTMMAPNode = NULL;


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;

	TMMAP_Node_t * pTmp;
	TMMAP_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 = pTMMAPNode;
	while(pTmp != NULL)
	{
		if( (phy_addr >= pTmp->Start_P) && 
			( (phy_addr + size) <= (pTmp->Start_P + pTmp->length) ) )
		{
            pTmp->refcount++;   /* referrence count increase by 1  */
			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 | O_SYNC);
		if (fd < 0)
		{
			printf("memmap():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("memmap():mmap @ 0x%x error!\n", phy_addr_in_page);
		return NULL;
	}

	/* add this mmap to MMAP Node */
	pNew = (TMMAP_Node_t *)malloc(sizeof(TMMAP_Node_t));
    if(NULL == pNew)
    {
   printf("memmap():malloc new node failed!\n");
        return NULL;
    }
	pNew->Start_P = phy_addr_in_page;
	pNew->Start_V = (unsigned int)addr;
	pNew->length = size_in_page;
    pNew->refcount = 1;
	pNew->next = NULL;
	
	if(pTMMAPNode == NULL)
	{
		pTMMAPNode = pNew;
	}
	else
	{
		pTmp = pTMMAPNode;
		while(pTmp->next != NULL)
		{
			pTmp = pTmp->next;
		}

		pTmp->next = pNew;
	}

	return (void *)(addr+page_diff);
//#endif
}
void key_read(){
	uint32_t ulOld;
	uint32_t ulAddr;
	int key;
	void* pMem  = NULL;
while (1){
	pMem = memmap(0x12150000, DEFAULT_MD_LEN); //gpio0
	printf("+++%p\n\r",pMem);
	
	ulOld = *(uint32_t *)((char *)pMem + 0x3FC);

	printf("0x%08lX\n",ulOld);

	key = (ulOld &0x04)>>2; //get gpio0_2 
	printf("key: %d\n\r",key);

	sleep(1);
}

}