江西 网站制作,西安官网seo方法,seo网站推广主要目的不包括,小程序开发外包费用以TC58NVG2S3ETA00 为例#xff1a; 下面是它的一些物理参数#xff1a; 图一 图二 图三 图四 图五 图6-0 图6-1 说明一下#xff0c;在图6-1中中间的那个布局表可以看做是实际的NandFlash一页数据的布局#xff0c;其中Data区域用于存放有效的数据#xff0c;也就是我们可… 以TC58NVG2S3ETA00 为例 下面是它的一些物理参数 图一 图二 图三 图四 图五 图6-0 图6-1 说明一下在图6-1中中间的那个布局表可以看做是实际的NandFlash一页数据的布局其中Data区域用于存放有效的数据也就是我们可以通过类似read、write、pread、pwrite可以访问的区域那每页中的64字节的OOB区域是无法通过前面的几个函数访问的他们会自动跳过OOB区域访问OOB区域需要借助特殊的命令。 简单说明一下Data A(512B)对应的ECC校验码存放在ECC for Data A(4 byte)中OOB A 8byte) 对应的ECC校验码存放在紧接着的下一个ECC for Data A4 byte)中虽然用4字节存放ECC但是对于本例ECC只占3个字节。在实际使用中如果解决方案中用不到OOB A/B/C/D可以不用管他们对应的ECC只需要关心Data区域对应的ECC。如果使能了硬件ECC硬件会自动把计算生成的ECC写到OOB中。可以参考http://www.cnblogs.com/pengdonglin137/p/3467960.html 。 读NandFlash需要按页读即一次读一页写NandFlash需要按页写即每次写一页擦除NandFlash需要按块擦即每次要擦除一块。 对与NandFlash等块设备的访问操作mtd-utils工具集中提供了非常好的支持可以到http://www.linux-mtd.infradead.org/进行了解要使用mtd-utils工具集首先需要搞到mtd-utils的源码并且使用目标设备上的交叉工具编译链进行编译具体方法可以参考http://www.cnblogs.com/pengdonglin137/p/3415550.html其中介绍了如何生成可以再目标板上运行的mtd-utils工具。关于mtd-utils工具的使用可以参考http://www.cnblogs.com/pengdonglin137/p/3415663.html 其中介绍了mtd-utils中常用的工具。 我们可以参考mtd-utils中工具的实现从而完成在自己的应用程序中实现对NandFlash的操作。常用的命令如下 #define MEMGETINFO _IOR(M, 1, struct mtd_info_user) #define MEMERASE _IOW(M, 2, struct erase_info_user) #define MEMWRITEOOB _IOWR(M, 3, struct mtd_oob_buf) #define MEMREADOOB _IOWR(M, 4, struct mtd_oob_buf) #define MEMLOCK _IOW(M, 5, struct erase_info_user) #define MEMUNLOCK _IOW(M, 6, struct erase_info_user) #define MEMGETREGIONCOUNT _IOR(M, 7, int) #define MEMGETREGIONINFO _IOWR(M, 8, struct region_info_user) #define MEMSETOOBSEL _IOW(M, 9, struct nand_oobinfo) #define MEMGETOOBSEL _IOR(M, 10, struct nand_oobinfo) #define MEMGETBADBLOCK _IOW(M, 11, __kernel_loff_t) #define MEMSETBADBLOCK _IOW(M, 12, __kernel_loff_t) #define OTPSELECT _IOR(M, 13, int) #define OTPGETREGIONCOUNT _IOW(M, 14, int) #define OTPGETREGIONINFO _IOW(M, 15, struct otp_info) #define OTPLOCK _IOR(M, 16, struct otp_info) #define ECCGETLAYOUT _IOR(M, 17, struct nand_ecclayout_user) #define ECCGETSTATS _IOR(M, 18, struct mtd_ecc_stats) #define MTDFILEMODE _IO(M, 19) #define MEMERASE64 _IOW(M, 20, struct erase_info_user64) #define MEMWRITEOOB64 _IOWR(M, 21, struct mtd_oob_buf64) #define MEMREADOOB64 _IOWR(M, 22, struct mtd_oob_buf64) #define MEMISLOCKED _IOR(M, 23, struct erase_info_user) 打开设备 这里需要注意的是打开的设备结点是/dev/mtd?而不是/dec/mtdblock?原因可以参考 http://www.cnblogs.com/pengdonglin137/p/3316523.html其中介绍了mtd与mtdblock的区别。 fd open (/dev/mtd0, O_SYNC | O_RDWR); 获取设备信息 #include linux/types.h structmtd_info_user { __u8 type; __u32 flags; __u32 size; // Total size of the MTD __u32 erasesize;__u32 writesize;__u32 oobsize;// Amount of OOB data per block (e.g. 16)/* The below two fields are obsolete and broken, do not use them * (TODO: remove at some point) */ __u32 ecctype;__u32 eccsize;
};struct mtd_info_user mtd; ioctl(fd, MEMGETINFO,mtd) ; 其中type可以用来区分是NorFlash还是NandFlash。 擦除NandFlash #include mtd/mtd-abi.h
#include linux/types.hstruct erase_info_user {__u32 start;__u32 length;
};typedef struct erase_info_user erase_info_t;erase_info_t erase;int isNAND, bbtest 1;erase.length DevInfo-erasesize;
// erase.length 表示的是擦除大小也就是一块的大小如128KB
// DevInfo-size 为某个/dev/mtdx的大小
// erasse.start应该是按块对齐递增isNAND (DevInfo-typenum MTD_NANDFLASH) ? 1 : 0;for (erase.start 0; erase.start DevInfo-size; erase.start DevInfo-erasesize)
{if (bbtest) {loff_t offset erase.start;int ret ioctl(DevInfo-fd, MEMGETBADBLOCK, offset); //判断是不是坏块if (ret 0) {if (!quiet)DEBUG (\nSkipping bad block at 0x%08x\n, erase.start);continue;//发现是坏块应该跳过} else if (ret 0) {if (errno EOPNOTSUPP) {bbtest 0;if (isNAND) {fprintf(stderr, %s: Bad block check not available\n, DevInfo-dir);return 1;}} else {fprintf(stderr, \n%s: MTD get bad block failed: %s\n, DevInfo-dir, strerror(errno));return 1;}}}if (!quiet){fprintf(stderr, \rErasing %d Kibyte %x -- %2llu %% complete., \(DevInfo-erasesize) / 1024, erase.start,(unsigned long long) erase.start * 100 / (DevInfo-size));}if (ioctl(DevInfo-fd, MEMERASE, erase) ! 0) //执行擦除操作{fprintf(stderr, \n%s: MTD Erase failure: %s\n, DevInfo-dir,strerror(errno));continue;}
} 写NandFlash 这里分为写数据区和写OOB区 写数据区对于本例一次要写一页也就是2KB写OOB区对于本例可以操作的只有32字节剩下的32字节用于存放ECC。 struct mtd_oob_buf {__u32 start;__u32 length;unsigned char *ptr;
};int nandwrite(DeviceInfo* meminfo)
{int imglen 0, pagelen;bool baderaseblock false;int blockstart -1;loff_t offs;int ret, readlen;unsigned char tmp_oob[32];//OOB A/B/C/D,一共32字节struct mtd_oob_buf OOB_INFO ;sourceaddr meminfo-head-file_offset; //要读的部分在镜像文件中的偏移量sourcelen meminfo-head-size; //要读的部分的大小int num_to_read 0;OOB_INFO.start 0;OOB_INFO.length meminfo-head-oob_usr_length; //32字节用户可以访问的OOB的大小也就是OOB A/B/C/DOOB_INFO.ptr tmp_oob;pagelen meminfo-writesize; // 2KBimglen sourcelen; // 镜像文件的长度
mtdoffset meminfo-head-flash_offset; //要写的部分在/dev/mtdx中的偏移量以字节为单位/* Determine if we are reading from standard input or from a file. */if (0 sourceaddr) {DEBUG(Have no sourceaddr return ****************************\n);return 1;}// Check, if length fits into deviceif ( ((imglen / pagelen) * meminfo-writesize) (meminfo-size - mtdoffset)) {fprintf (stderr, Image %d bytes, NAND page %d bytes, OOB area %u bytes, device size %u bytes\n,imglen, pagelen, meminfo-writesize, meminfo-size);perror (Input file does not fit into device);goto closeall;}while ((imglen0) (mtdoffset meminfo-size)){//blockstart 将来存放的是正在写的那块的起始地址并且是块对齐的//mtdoffset 表示的是在某个mtd设备中的整体偏移量可以按块递增也可以按页递增//设置blockstart的目的是:// 假如检测到一个好的块开始进行写操作但是在写的过程中发生了写错误可以认为这块已经//是坏块了需要重新再找一个好的块然后重新写入之前的数据因此需要知道刚才那个坏块的起始地址// mtdoffset (~meminfo-erasesize 1) 这种获取块起始地址的算法值得借鉴while (blockstart ! (mtdoffset (~meminfo-erasesize 1))){blockstart mtdoffset (~meminfo-erasesize 1);offs blockstart;baderaseblock false;if (!quiet){fprintf (stderr, \rWriting data to block %d at offset 0x%x, \blockstart / meminfo-erasesize, blockstart);}/* Check all the blocks in an erase block for bad blocks */// meminfo-fd 是某个/dev/mtdx的文件描述符do {if ((ret ioctl(meminfo-fd, MEMGETBADBLOCK, offs)) 0){perror(ioctl(MEMGETBADBLOCK));goto closeall;}if (ret 1){baderaseblock true;if (!quiet){fprintf (stderr, Bad block at %x block(s) from %x will be skipped\n,(int) offs, blockstart);}}if (baderaseblock){mtdoffset blockstart meminfo-erasesize;}offs meminfo-erasesize;} while ( offs blockstart meminfo-erasesize );}readlen meminfo-writesize; // 2KBif (0 ! sourceaddr){if((meminfo-head-imageType YAFFS) || (meminfo-head-imageType OOB_RAW)){writeoob true;}else{writeoob false;}memset(writebuf, 0xff, sizeof(writebuf));if(imglen readlen){num_to_read imglen;}else{num_to_read readlen;}// 从镜像文件中偏移量为sourceaddr处读取num_to_read个字节到writebuf中// ALLIMAGEFD 为镜像文件的文件描述符if(pread(ALLIMAGEFD, writebuf, num_to_read, sourceaddr) 0) {perror(fail to pread\n);return -1;}sourceaddr num_to_read;if(writeoob){memset(tmp_oob, 0xff , OOB_FREE_MAX);// 从镜像文件中偏移量为sourceaddrmeminfo-head-oob_usr_offset处读取meminfo-head-oob_usr_length个字节到tmp_oob中其中meminfo-head-oob_usr_offset是OOB A相对与OOB区域的偏移量meminfo-head-oob_usr_length 在本例中为32字节if(pread(ALLIMAGEFD, tmp_oob, meminfo-head-oob_usr_length, sourceaddrmeminfo-head-oob_usr_offset) 0){perror(fail to pread\n);return -1;}sourceaddr meminfo-oobsize;}}if(-1 pwrite(meminfo-fd, writebuf, meminfo-writesize, mtdoffset)) //写NandFlash{/*下面这段程序所完成的就是刚才所说的在写之前检测到是好块但是在写的过程出现了写错误这个时候需要完成?如下流程:1、计算已经在当前块上写入多少内容,比如下面的rewind_blocks是为了计算在当前块上已经写了多少页这里需要注意的是rewind_bytes又加了一个readlen也就是一页的大小目的是保证sourceaddr的可以回退到刚开始写当前块是sourceaddr的值可以看到在上面的程序中每次将要写的内容读到writebuf后sourceaddr已经进行了自增操作并没有保证刚读到writebuf中的内容可以成功写入。但是mtdoffset进行自增的前提是偏移量为mtdoffset的页写成功。其实程序可以这么改进:将sourceaddr的自增操作跟mtdoffset的自增操作放在一起此时rewind_bytes就不需要再加readlen了。对于oob一般只有yaffs镜像中有oob而向cramfs、jffs2、ubifs这没有如果有oob也需要对rewind_byte进行处理2、对当前块进行擦除3、如果需要进行坏块标记则将当前块标记为坏块4、将mtdoffset指向当前块的下一块起始地址5、恢复imglen为刚开始处理当前块时的值由于imglen也是保证当前页成功写入后才自减所以只需要加上rewind_blocks即可*/int rewind_blocks;off_t rewind_bytes;erase_info_t erase;perror(ioctl(MEMEWRITEPAGE));/* Must rewind to blockstart if we can */rewind_blocks (mtdoffset - blockstart) / meminfo-writesize; /* Not including the one we just attempted */rewind_bytes (rewind_blocks * meminfo-writesize) readlen;if (writeoob){rewind_bytes (rewind_blocks 1) * meminfo-oobsize;}sourceaddr - rewind_bytes;erase.start blockstart;erase.length meminfo-erasesize;fprintf(stderr, Erasing failed write from %08lx-%08lx\n,(long)erase.start, (long)erase.starterase.length-1);if (ioctl(meminfo-fd, MEMERASE, erase) ! 0){perror(MEMERASE);goto closeall;}if (markbad){loff_t bad_addr mtdoffset (~meminfo-erasesize 1);fprintf(stderr, Marking block at %08lx bad\n, (long)bad_addr);if (ioctl(meminfo-fd, MEMSETBADBLOCK, bad_addr)) {perror(MEMSETBADBLOCK);/* But continue anyway */}}mtdoffset blockstart meminfo-erasesize;imglen rewind_blocks * meminfo-writesize;if(writeoob){imglen rewind_blocks * meminfo-oobsize;}continue;}imglen - readlen;if(writeoob){imglen - meminfo-oobsize;OOB_INFO.start mtdoffset;if (ioctl(meminfo-fd, MEMWRITEOOB, OOB_INFO)){perror(fail to ioctl);}}mtdoffset meminfo-writesize;}closeall:if ((imglen 0)){perror (Data was only partially written due to error\n);exit (EXIT_FAILURE);}return EXIT_SUCCESS;
} 对于写NandFlash有的设备支持一次性把data和oob一块写进去。代码如下 struct mtd_info_user {uint8_t type;uint32_t flags;uint32_t size; // Total size of the MTDuint32_t erasesize;uint32_t writesize;uint32_t oobsize; // Amount of OOB data per block (e.g. 16)/* The below two fields are obsolete and broken, do not use them* (TODO: remove at some point) */uint32_t ecctype;uint32_t eccsize;
};struct mtd_epage_buf
{unsigned long long start;unsigned long data_len;unsigned long oob_len;unsigned char * data_ptr;unsigned char * oob_ptr;
};#define MEMEWRITEPAGE _IOWR(M, 23, struct mtd_epage_buf) #define MAX_PAGE_SIZE 8192#define MAX_OOB_SIZE 512 /* * Buffer array used for writing data */unsigned char writebuf[MAX_PAGE_SIZE];char oobbuf[MAX_OOB_SIZE]; int nandwrite(int argc, char * const argv[])
{/*int cnt 0;*/int fd -1;/*int ifd -1;*/int imglen 0, pagelen;bool baderaseblock false;int blockstart -1;struct mtd_info_user meminfo;struct mtd_epage_buf eccbuf;loff_t offs;int ret, readlen;/*process_options(argc, argv);*/mtdoffset 0; /* reinit */erase_buffer(oobbuf, sizeof(oobbuf));if (pad writeoob) {fprintf(stderr, Cant pad when oob data is present.\n);exit (EXIT_FAILURE);}/* Open the device */if ((fd open(mtd_device, O_RDWR)) -1) {perror(mtd_device);exit (EXIT_FAILURE);}/* Fill in MTD device capability structure */if (ioctl(fd, MEMGETINFO, meminfo) ! 0) {perror(MEMGETINFO);close(fd);exit (EXIT_FAILURE);}/* Determine if we are reading from standard input or from a file. */if (NULL sourceaddr) {DEBUG(Have no sourceaddr return ****************************\n);return 0;}pagelen meminfo.writesize ((writeoob) ? meminfo.oobsize : 0);/** For the standard input case, the input size is merely an* invariant placeholder and is set to the write page* size. Otherwise, just use the input file size.** TODO: Add support for the -l,--lengthlength option (see* previous discussion by Tommi Airikka tommi.airikkaericsson.com at* http://lists.infradead.org/pipermail/linux-mtd/2008-September/* 022913.html*/imglen sourcelen;// Check, if file is page-alignedif ((!pad) ((imglen % pagelen) ! 0)) {fprintf (stderr, Input file is not page-aligned. Use the padding option.\n);goto closeall;}// Check, if length fits into deviceif ( ((imglen / pagelen) * meminfo.writesize) (meminfo.size - mtdoffset)) {fprintf (stderr, Image %d bytes, NAND page %d bytes, OOB area %u bytes, device size %u bytes\n,imglen, pagelen, meminfo.writesize, meminfo.size);perror (Input file does not fit into device);goto closeall;}const int allSizeConst imglen;/*DEBUG(file:%s, line:%d, imglen:%d, mtdoffset:%d, meminfo.size:%d\n, __FILE__, __LINE__, imglen, mtdoffset, meminfo.size);*//** Get data from input and write to the device while there is* still input to read and we are still within the device* bounds. Note that in the case of standard input, the input* length is simply a quasi-boolean flag whose values are page* length or zero.*/while (imglen (mtdoffset meminfo.size)) {// new eraseblock , check for bad block(s)// Stay in the loop to be sure if the mtdoffset changes because// of a bad block, that the next block that will be written to// is also checked. Thus avoiding errors if the block(s) after the// skipped block(s) is also bad (number of blocks depending on// the blockalignwhile (blockstart ! (mtdoffset (~meminfo.erasesize 1))) {blockstart mtdoffset (~meminfo.erasesize 1);offs blockstart;baderaseblock false;if (!quiet)fprintf (stdout, Writing data to block %d at offset 0x%x\n,blockstart / meminfo.erasesize, blockstart);/* Check all the blocks in an erase block for bad blocks */do {if ((ret ioctl(fd, MEMGETBADBLOCK, offs)) 0) {perror(ioctl(MEMGETBADBLOCK));goto closeall;}if (ret 1) {baderaseblock true;if (!quiet)fprintf (stderr, Bad block at %x block(s) from %x will be skipped\n,(int) offs, blockstart);}if (baderaseblock) {mtdoffset blockstart meminfo.erasesize;}offs meminfo.erasesize;} while ( offs blockstart meminfo.erasesize );}readlen meminfo.writesize;if (NULL ! sourceaddr) {if (pad (imglen readlen)){readlen imglen;erase_buffer(writebuf readlen, meminfo.writesize - readlen);}memcpy(writebuf, sourceaddr, readlen);sourceaddr readlen;} if (writeoob) {memcpy(oobbuf, sourceaddr, meminfo.oobsize);sourceaddr meminfo.oobsize;}eccbuf.data_ptr writebuf;eccbuf.data_len meminfo.writesize;eccbuf.oob_ptr oobbuf;eccbuf.oob_len meminfo.oobsize;eccbuf.start mtdoffset;if (ioctl(fd, MEMEWRITEPAGE, eccbuf) ! 0){int rewind_blocks;off_t rewind_bytes;erase_info_t erase;perror(ioctl(MEMEWRITEPAGE));/* Must rewind to blockstart if we can */rewind_blocks (mtdoffset - blockstart) / meminfo.writesize; /* Not including the one we just attempted */rewind_bytes (rewind_blocks * meminfo.writesize) readlen;if (writeoob)rewind_bytes (rewind_blocks 1) * meminfo.oobsize;sourceaddr - rewind_bytes;erase.start blockstart;erase.length meminfo.erasesize;fprintf(stderr, Erasing failed write from %08lx-%08lx\n,(long)erase.start, (long)erase.starterase.length-1);if (ioctl(fd, MEMERASE, erase) ! 0) {perror(MEMERASE);goto closeall;}if (markbad) {loff_t bad_addr mtdoffset (~meminfo.erasesize 1);fprintf(stderr, Marking block at %08lx bad\n, (long)bad_addr);if (ioctl(fd, MEMSETBADBLOCK, bad_addr)) {perror(MEMSETBADBLOCK);/* But continue anyway */}}mtdoffset blockstart meminfo.erasesize;imglen rewind_blocks * meminfo.writesize;continue;}imglen - (readlen meminfo.oobsize);mtdoffset meminfo.writesize; }closeall:close(fd);if ((imglen 0)) {perror (Data was only partially written due to error\n);exit (EXIT_FAILURE);}/* Return happy */return EXIT_SUCCESS;
} 读OOB 读OOB跟写OOB类似只不过使用的命令是MEMREADOOB。 #include sys/ioctl.h
#include stdio.h
#include mtd/mtd-user.h
#include sys/types.h
#include sys/stat.h
#include fcntl.h
#include unistd.h
#include string.h
#include stdlib.h#define N 32
#define OFS (0)
#define block_size (128*1024)
#define page_size (2*1024)int main(int argc, const char *argv[])
{int fd;int i, j;unsigned char oob_data[32] {0x53, 0x50, 0x4c, 0x20, 0, 0xff, 0, 0xff, 0x53, 0x50, 0x4c, 0x20, 0, 0xff, 0, 0xff, 0x53, 0x50, 0x4c, 0x20, 0, 0xff, 0, 0xff, 0x53, 0x50, 0x4c, 0x20, 0, 0xff, 0, 0xff};unsigned char oobbuf[N];struct mtd_oob_buf oob {0, N, oobbuf};struct mtd_oob_buf my_oob {0, N, oob_data};fd open(/dev/mtd0, O_RDWR);if(fd 0){perror(fail to open\n);exit(-1);}if(ioctl(fd, MEMWRITEOOB, my_oob)){perror(fail to ioctl);exit(-1);}memset(oobbuf, 0, sizeof(oobbuf));oob.start OFS;if (ioctl(fd, MEMREADOOB, oob)){perror(fail to ioctl);exit(-1);}for(i0; iN; i){if(i%8 0){printf(\n);}printf(%#x , oobbuf[i]);}printf(\n\n);close (fd);return 0;} 以上只是本人在工作中遇到的仅供参考。 转载于:https://www.cnblogs.com/pengdonglin137/p/3468953.html
