ZYNQnandflush读写实例

ZYNQ是Xilinx公司推出的一款SoC芯片，其中包含了NAND闪存控制器。在ZYNQ上使用nandflush进行读写操作需要进行一些特殊的配置。以下是一个ZYNQnandflush读写的示例：

#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/mman.h>

#define PAGE_SIZE       0x2000
#define BLOCK_SIZE      0x40000

#define NAND_BASEADDR   0xE1000000
#define NAND_SIZE       0x1000
#define NAND_CMD_ADDR   0xE1000010
#define NAND_ADDR_ADDR  0xE1000014
#define NAND_DATA_ADDR  0xE1000018

volatile unsigned int *nand_cmd;
volatile unsigned int *nand_addr;
volatile unsigned char *nand_data;

void zynq_nand_init(void)
{
    int fd;

    fd = open("/dev/mem", O_RDWR | O_SYNC);
    if (fd == -1) {
        perror("open");
        exit(EXIT_FAILURE);
    }

    nand_cmd = mmap(NULL, NAND_SIZE, PROT_READ | PROT_WRITE, MAP_SHARED, fd, NAND_CMD_ADDR);
    if (nand_cmd == MAP_FAILED) {
        perror("mmap");
        exit(EXIT_FAILURE);
    }

    nand_addr = mmap(NULL, NAND_SIZE, PROT_READ | PROT_WRITE, MAP_SHARED, fd, NAND_ADDR_ADDR);
    if (nand_addr == MAP_FAILED) {
        perror("mmap");
        exit(EXIT_FAILURE);
    }

    nand_data = mmap(NULL, NAND_SIZE, PROT_READ | PROT_WRITE, MAP_SHARED, fd, NAND_DATA_ADDR);
    if (nand_data == MAP_FAILED) {
        perror("mmap");
        exit(EXIT_FAILURE);
    }

    close(fd);
}

void zynq_nand_read(unsigned int page, unsigned int offset, unsigned char *data, unsigned int length)
{
    unsigned int addr;

    // 设置页和偏移量
    addr = (page * BLOCK_SIZE) + (offset % PAGE_SIZE);

    // 发送读命令
    nand_cmd[0] = 0x00;
    nand_addr[0] = addr & 0xFF;
    nand_addr[1] = (addr >> 8) & 0xFF;
    nand_addr[2] = (addr >> 16) & 0xFF;
    nand_cmd[0] = 0x30;

    // 读取数据
    while (length--) {
        *data++ = *nand_data;
    }
}

void zynq_nand_write(unsigned int page, unsigned int offset, unsigned char *data, unsigned int length)
{
    unsigned int addr;

    // 设置页和偏移量
    addr = (page * BLOCK_SIZE) + (offset % PAGE_SIZE);

    // 发送写命令
    nand_cmd[0] = 0x80;
    nand_addr[0] = addr & 0xFF;
    nand_addr[1] = (addr >> 8) & 0xFF;
    nand_addr[2] = (addr >> 16) & 0xFF;

    // 写入数据
    while (length--) {
        *nand_data = *data++;
    }

    // 发送写确认命令
    nand_cmd[0] = 0x10;
}

int main(int argc, char *argv[])
{
    unsigned char *data;
    unsigned int page, offset, length;

    // 初始化NAND控制器
    zynq_nand_init();

    // 设置页和偏移量
    page = 0;
    offset = 0;

    // 分配内存空间
    length = PAGE_SIZE;
    data = malloc(length);
    if (!data) {
        perror("malloc");
        exit(EXIT_FAILURE);
    }

    // 读取数据
    zynq_nand_read(page, offset, data, length);

    // 修改数据
    data[0] = 0x55;
    data[1] = 0xAA;

    // 写入数据
    zynq_nand_write(page, offset, data, length);

    // 释放内存空间
    free(data);

    return 0;
}

这个示例首先通过mmap函数将NAND控制器的寄存器映射到用户空间。它设置要读取的页和偏移量，并分配足够的内存来存储要读取或写入的数据。然后，它使用zynq_nand_read和zynq_nand_write函数读取和写入数据。最后，它释放内存空间并关闭NAND控制器的映射。