nand_util.c

ATMEL单片机可用的文件系统源代码

/***********************************************************************/
/*                                                                     */
/*   Module:  nand_util.c                                              */
/*   Release: 2004.5                                                   */
/*   Version: 2004.1                                                   */
/*   Purpose: Specific NAND code for the flash file system             */
/*                                                                     */
/*---------------------------------------------------------------------*/
/*                                                                     */
/*               Copyright 2004, Blunk Microsystems                    */
/*                      ALL RIGHTS RESERVED                            */
/*                                                                     */
/*   Licensees have the non-exclusive right to use, modify, or extract */
/*   this computer program for software development at a single site.  */
/*   This program may be resold or disseminated in executable format   */
/*   only. The source code may not be redistributed or resold.         */
/*                                                                     */
/***********************************************************************/
#include "flashfsp.h"

#if INC_NAND_FS && NUM_FFS_VOLS

/***********************************************************************/
/* Symbol Definitions                                                  */
/***********************************************************************/
#define CRC32_START     0xFFFFFFFF  /* starting CRC bit string */
#define CRC32_FINAL     0xDEBB20E3  /* summed over data and CRC */

#define RWR_CTRL_OK     5

/***********************************************************************/
/* Macro Definitions                                                   */
/***********************************************************************/
#define CRC_UPDATE(crc, c)  ((crc >> 8) ^ FfsCrcTab[(ui8)(crc ^ c)])

/***********************************************************************/
/* Constant Data Definitions                                           */
/***********************************************************************/
/*
** CRC Lookup Table
*/
static const ui32 FfsCrcTab[256] =
{
  0x00000000, 0x77073096, 0xEE0E612C, 0x990951BA,
  0x076DC419, 0x706AF48F, 0xE963A535, 0x9E6495A3,
  0x0EDB8832, 0x79DCB8A4, 0xE0D5E91E, 0x97D2D988,
  0x09B64C2B, 0x7EB17CBD, 0xE7B82D07, 0x90BF1D91,
  0x1DB71064, 0x6AB020F2, 0xF3B97148, 0x84BE41DE,
  0x1ADAD47D, 0x6DDDE4EB, 0xF4D4B551, 0x83D385C7,
  0x136C9856, 0x646BA8C0, 0xFD62F97A, 0x8A65C9EC,
  0x14015C4F, 0x63066CD9, 0xFA0F3D63, 0x8D080DF5,
  0x3B6E20C8, 0x4C69105E, 0xD56041E4, 0xA2677172,
  0x3C03E4D1, 0x4B04D447, 0xD20D85FD, 0xA50AB56B,
  0x35B5A8FA, 0x42B2986C, 0xDBBBC9D6, 0xACBCF940,
  0x32D86CE3, 0x45DF5C75, 0xDCD60DCF, 0xABD13D59,
  0x26D930AC, 0x51DE003A, 0xC8D75180, 0xBFD06116,
  0x21B4F4B5, 0x56B3C423, 0xCFBA9599, 0xB8BDA50F,
  0x2802B89E, 0x5F058808, 0xC60CD9B2, 0xB10BE924,
  0x2F6F7C87, 0x58684C11, 0xC1611DAB, 0xB6662D3D,
  0x76DC4190, 0x01DB7106, 0x98D220BC, 0xEFD5102A,
  0x71B18589, 0x06B6B51F, 0x9FBFE4A5, 0xE8B8D433,
  0x7807C9A2, 0x0F00F934, 0x9609A88E, 0xE10E9818,
  0x7F6A0DBB, 0x086D3D2D, 0x91646C97, 0xE6635C01,
  0x6B6B51F4, 0x1C6C6162, 0x856530D8, 0xF262004E,
  0x6C0695ED, 0x1B01A57B, 0x8208F4C1, 0xF50FC457,
  0x65B0D9C6, 0x12B7E950, 0x8BBEB8EA, 0xFCB9887C,
  0x62DD1DDF, 0x15DA2D49, 0x8CD37CF3, 0xFBD44C65,
  0x4DB26158, 0x3AB551CE, 0xA3BC0074, 0xD4BB30E2,
  0x4ADFA541, 0x3DD895D7, 0xA4D1C46D, 0xD3D6F4FB,
  0x4369E96A, 0x346ED9FC, 0xAD678846, 0xDA60B8D0,
  0x44042D73, 0x33031DE5, 0xAA0A4C5F, 0xDD0D7CC9,
  0x5005713C, 0x270241AA, 0xBE0B1010, 0xC90C2086,
  0x5768B525, 0x206F85B3, 0xB966D409, 0xCE61E49F,
  0x5EDEF90E, 0x29D9C998, 0xB0D09822, 0xC7D7A8B4,
  0x59B33D17, 0x2EB40D81, 0xB7BD5C3B, 0xC0BA6CAD,
  0xEDB88320, 0x9ABFB3B6, 0x03B6E20C, 0x74B1D29A,
  0xEAD54739, 0x9DD277AF, 0x04DB2615, 0x73DC1683,
  0xE3630B12, 0x94643B84, 0x0D6D6A3E, 0x7A6A5AA8,
  0xE40ECF0B, 0x9309FF9D, 0x0A00AE27, 0x7D079EB1,
  0xF00F9344, 0x8708A3D2, 0x1E01F268, 0x6906C2FE,
  0xF762575D, 0x806567CB, 0x196C3671, 0x6E6B06E7,
  0xFED41B76, 0x89D32BE0, 0x10DA7A5A, 0x67DD4ACC,
  0xF9B9DF6F, 0x8EBEEFF9, 0x17B7BE43, 0x60B08ED5,
  0xD6D6A3E8, 0xA1D1937E, 0x38D8C2C4, 0x4FDFF252,
  0xD1BB67F1, 0xA6BC5767, 0x3FB506DD, 0x48B2364B,
  0xD80D2BDA, 0xAF0A1B4C, 0x36034AF6, 0x41047A60,
  0xDF60EFC3, 0xA867DF55, 0x316E8EEF, 0x4669BE79,
  0xCB61B38C, 0xBC66831A, 0x256FD2A0, 0x5268E236,
  0xCC0C7795, 0xBB0B4703, 0x220216B9, 0x5505262F,
  0xC5BA3BBE, 0xB2BD0B28, 0x2BB45A92, 0x5CB36A04,
  0xC2D7FFA7, 0xB5D0CF31, 0x2CD99E8B, 0x5BDEAE1D,
  0x9B64C2B0, 0xEC63F226, 0x756AA39C, 0x026D930A,
  0x9C0906A9, 0xEB0E363F, 0x72076785, 0x05005713,
  0x95BF4A82, 0xE2B87A14, 0x7BB12BAE, 0x0CB61B38,
  0x92D28E9B, 0xE5D5BE0D, 0x7CDCEFB7, 0x0BDBDF21,
  0x86D3D2D4, 0xF1D4E242, 0x68DDB3F8, 0x1FDA836E,
  0x81BE16CD, 0xF6B9265B, 0x6FB077E1, 0x18B74777,
  0x88085AE6, 0xFF0F6A70, 0x66063BCA, 0x11010B5C,
  0x8F659EFF, 0xF862AE69, 0x616BFFD3, 0x166CCF45,
  0xA00AE278, 0xD70DD2EE, 0x4E048354, 0x3903B3C2,
  0xA7672661, 0xD06016F7, 0x4969474D, 0x3E6E77DB,
  0xAED16A4A, 0xD9D65ADC, 0x40DF0B66, 0x37D83BF0,
  0xA9BCAE53, 0xDEBB9EC5, 0x47B2CF7F, 0x30B5FFE9,
  0xBDBDF21C, 0xCABAC28A, 0x53B39330, 0x24B4A3A6,
  0xBAD03605, 0xCDD70693, 0x54DE5729, 0x23D967BF,
  0xB3667A2E, 0xC4614AB8, 0x5D681B02, 0x2A6F2B94,
  0xB40BBE37, 0xC30C8EA1, 0x5A05DF1B, 0x2D02EF8D
};

const ui8 NumberOnes[] =
{
/*0  1  2  3  4  5  6  7  8  9  A  B  C  D  E  F */
  0, 1, 1, 2, 1, 2, 2, 3, 1, 2, 2, 3, 2, 3, 3, 4,
};

#if FFS_DEBUG
int printf(const char *, ...);
#endif

/***********************************************************************/
/* Local Function Definitions                                          */
/***********************************************************************/

/***********************************************************************/
/*   ctrl_page: Check the page's type, read from its extra bytes       */
/*                                                                     */
/*       Input: type = page type                                       */
/*                                                                     */
/*     Returns: TRUE if page holds control information, else FALSE     */
/*                                                                     */
/***********************************************************************/
static int ctrl_page(ui32 addr)
{
  int ones = 0;
  ui32 type;

  /*-------------------------------------------------------------------*/
  /* Read the page's type code.                                        */
  /*-------------------------------------------------------------------*/
  type = Flash->driver.nand.read_type(addr, Flash->vol);

  /*-------------------------------------------------------------------*/
  /* Do a quick check for an error-free data sector type code.         */
  /*-------------------------------------------------------------------*/
  if (type == 0xFFFFFFFF || type == 0x00000000)
    return FALSE;

  /*-------------------------------------------------------------------*/
  /* Count number of 1 valued bits in type code.                       */
  /*-------------------------------------------------------------------*/
  while (type)
  {
    ones += NumberOnes[type & 0xF];
    type >>= 4;
  }

  /*-------------------------------------------------------------------*/
  /* If between 8 and 24 bits are 1, it's a control sector.            */
  /*-------------------------------------------------------------------*/
  return (8 < ones) && (ones < 24);
}

/***********************************************************************/
/* is_ctrl_sect: Check if a sector contains control information and    */
/*               update the control CRC calculation                    */
/*                                                                     */
/*     Inputs: sect = sector to check                                  */
/*             crc  = current CRC value                                */
/*                                                                     */
/*    Returns: TRUE if sector has control info, FALSE otherwise        */
/*                                                                     */
/***********************************************************************/
static ui8 is_ctrl_sect(ui32 sect, ui32 *crc)
{
  int i;
  ui8 *buf = Flash->tmp_sect;
  ui32 addr = Flash->mem_base + Flash->sect_sz * sect;
  ui32 wear = Flash->blocks[sect / Flash->block_sects].wear_count;

  /*-------------------------------------------------------------------*/
  /* Read in a page at a time.                                         */
  /*-------------------------------------------------------------------*/
  for (i = 0; i < Flash->pages_per_sect; ++i, addr += Flash->page_size)
  {
    /*-----------------------------------------------------------------*/
    /* Check that the page contains control information.               */
    /*-----------------------------------------------------------------*/
    if (ctrl_page(addr) == FALSE)
      return FALSE;

    /*-----------------------------------------------------------------*/
    /* Read the page data.                                             */
    /*-----------------------------------------------------------------*/
    if (Flash->driver.nand.read_page(buf, addr, wear, Flash->vol))
      return FALSE;
    buf += Flash->page_size;
  }

  /*-------------------------------------------------------------------*/
  /* Perform CRC over it.                                              */
  /*-------------------------------------------------------------------*/
  buf = Flash->tmp_sect;
  for (i = 0; i < Flash->sect_sz; ++i)
    *crc = CRC_UPDATE(*crc, buf[i]);

  return TRUE;
}

/***********************************************************************/
/*   next_ctrl: Find next valid ctrl in volume, if any is present      */
/*                                                                     */
/*      Inputs: *start_sect = first sector to search                   */
/*                                                                     */
/*      Output: *seq_num = sequence number if valid ctrl info found    */
/*                                                                     */
/*     Returns: Starting sector number if control info found, else -1  */
/*             if no more valid ctrls in flash                         */
/*                                                                     */
/***********************************************************************/
static int next_ctrl(ui32 *start_sect, ui32 *seq_num)
{
  ui32 crc, num_sects, i, ctrl_sect;
  int r_val;

  /*-------------------------------------------------------------------*/
  /* Look through the sectors for ctrl info sectors.                   */
  /*-------------------------------------------------------------------*/
  for (; *start_sect < Flash->num_sects; *start_sect += 1)
  {
    /*-----------------------------------------------------------------*/
    /* Initialize the control information CRC calculation.             */
    /*-----------------------------------------------------------------*/
    crc = CRC32_START;

    /*-----------------------------------------------------------------*/
    /* If this sector is a control sector, check the ctrl validity.    */
    /*-----------------------------------------------------------------*/
    if (is_ctrl_sect(*start_sect, &crc))
    {
      /*---------------------------------------------------------------*/
      /* Get the control information size, in number of sectors.       */
      /*---------------------------------------------------------------*/
      num_sects = ((ui32 *)Flash->tmp_sect)[0];
#if FFS_SWAP_ENDIAN
      num_sects = ((num_sects & 0xFF) << 24) |
                  ((num_sects & 0xFF00) << 8) |
                  ((num_sects & 0xFF0000) >> 8) |
                  ((num_sects & 0xFF000000) >> 24);
#endif
      num_sects = (num_sects + Flash->sect_sz - 1) / Flash->sect_sz;

      /*---------------------------------------------------------------*/
      /* Check if the control information size is reasonable.          */
      /*---------------------------------------------------------------*/
      if (num_sects > 0 &&
          num_sects <= Flash->block_sects * Flash->max_set_blocks)
      {
        /*-------------------------------------------------------------*/
        /* Read the control sequence number.                           */
        /*-------------------------------------------------------------*/
        *seq_num = ((ui32 *)Flash->tmp_sect)[1];
#if FFS_SWAP_ENDIAN
        *seq_num = ((*seq_num & 0xFF) << 24) |
                   ((*seq_num & 0xFF00) << 8) |
                   ((*seq_num & 0xFF0000) >> 8) |
                   ((*seq_num & 0xFF000000) >> 24);
#endif

        /*-------------------------------------------------------------*/
        /* Read remaining sectors, updating the CRC and checking type. */
        /*-------------------------------------------------------------*/
        for (i = 1, ctrl_sect = *start_sect;; ++i)
        {
          /*-----------------------------------------------------------*/
          /* Check if we have read enough sectors.                     */
          /*-----------------------------------------------------------*/
          if (i == num_sects)
          {
            if (crc == CRC32_FINAL)
            {
              r_val = (int)*start_sect;
              *start_sect += num_sects;
              return r_val;
            }
            break;
          }

          /*-----------------------------------------------------------*/
          /* If current ctrl sect is at the end of a block, next ctrl  */
          /* sector is in next ctrl block.                             */
          /*-----------------------------------------------------------*/
          if ((ctrl_sect + 1) % Flash->block_sects == 0)
          {
            /*---------------------------------------------------------*/
            /* If next ctrl block has valid value, use it, else it's   */
            /* an invalid ctrl sector.                                 */
            /*---------------------------------------------------------*/
            ui8 hi_byte = Flash->tmp_sect[Flash->sect_sz - 2];
            ui8 lo_byte = Flash->tmp_sect[Flash->sect_sz - 1];
            ui16 next_ctrl_block = (ui16)((hi_byte << 8) | lo_byte);
            if (next_ctrl_block >= Flash->num_blocks)
              break;
            ctrl_sect = next_ctrl_block * Flash->block_sects +
                        Flash->hdr_sects;
          }
          else
            ++ctrl_sect;

          if (!is_ctrl_sect(ctrl_sect, &crc))
            break;
        }
      }
    }