hi3531du盘自动升级

spi nand flash 写入出现问题
static int nand_flash_write(unsigned long offset, unsigned long len, void *buf)
{
        int ret = 0;
        unsigned long offset_notify, write_start, write_len, write_step;
        char *pbuf = buf;
        size_t length;
        struct mtd_info *nandflash_info = get_nand_info();

        if (offset == 0) {
                /* As EB bit locates at the last page of first block must be checked
                   when running bootloader, so make sure the length is block size
                   algin at offset == 0 */
                length = len & (nandflash_info->erasesize - 1) ? (size_t)(len +
                        (nandflash_info->erasesize - len % nandflash_info->erasesize)) : len;
                write_step = nandflash_info->erasesize;
        } else {
                /* Make sure the length is page size algin */
                length = len & (nandflash_info->writesize - 1) ? (size_t)(len +
                        (nandflash_info->writesize - len % nandflash_info->writesize)) : len;
                write_step = nandflash_info->writesize;
        }

        write_start = offset;
        offset_notify = offset;
        write_len   = length;

        while (length > 0) {
                size_t block_offset = offset & (nandflash_info->erasesize - 1);
                size_t *rw_size;

                if (nandflash_info->block_isbad(nandflash_info,
                                offset & ~((loff_t)nandflash_info->erasesize - 1))) {
                        printf("Skip bad block 0x%08llx\n",
                                offset & ~((loff_t)nandflash_info->erasesize - 1));
                        offset += nandflash_info->erasesize - block_offset;
                        continue;
                }

                rw_size = (size_t *)&write_step;

                ret = nandflash_info->write(nand_flash, (size_t)offset, *rw_size,
                                rw_size, (u_char *)pbuf);
                if (ret) {
                        printf("NAND write to offset %lx failed %d\n",
                                        offset, ret);
                        break;
                }

                offset += write_step;
                pbuf   += write_step;
                length -= write_step;
                offset_notify += write_step;
                /* notify real time schedule */
                schedule_notify(offset_notify, write_len, write_start);
        }

        return ret;
}