flash.c

ATMEL公司的AT91RM9200芯片在嵌入式系统中应用非常多

    switch (value) {
    case (FLASH_WORD_SIZE)AMD_MANUFACT:
        info->flash_id = FLASH_MAN_AMD;
        break;
    case (FLASH_WORD_SIZE)FUJ_MANUFACT:
        info->flash_id = FLASH_MAN_FUJ;
        break;
    case (FLASH_WORD_SIZE)SST_MANUFACT:
        info->flash_id = FLASH_MAN_SST;
        break;
    default:
        info->flash_id = FLASH_UNKNOWN;
        info->sector_count = 0;
        info->size = 0;
        return (0);         /* no or unknown flash  */
    }
    printf("recognised manufacturer");

    value = addr2[ADDR3];          /* device ID        */
        debug ("\ndev_code=%x\n", value);

    switch (value) {
    case (FLASH_WORD_SIZE)AMD_ID_LV400T:
        info->flash_id += FLASH_AM400T;
        info->sector_count = 11;
        info->size = 0x00080000;
        break;              /* => 0.5 MB        */

    case (FLASH_WORD_SIZE)AMD_ID_LV400B:
        info->flash_id += FLASH_AM400B;
        info->sector_count = 11;
        info->size = 0x00080000;
        break;              /* => 0.5 MB        */

    case (FLASH_WORD_SIZE)AMD_ID_LV800T:
        info->flash_id += FLASH_AM800T;
        info->sector_count = 19;
        info->size = 0x00100000;
        break;              /* => 1 MB      */

    case (FLASH_WORD_SIZE)AMD_ID_LV800B:
        info->flash_id += FLASH_AM800B;
        info->sector_count = 19;
        info->size = 0x00100000;
        break;              /* => 1 MB      */

    case (FLASH_WORD_SIZE)AMD_ID_LV160T:
        info->flash_id += FLASH_AM160T;
        info->sector_count = 35;
        info->size = 0x00200000;
        break;              /* => 2 MB      */

    case (FLASH_WORD_SIZE)AMD_ID_LV160B:
        info->flash_id += FLASH_AM160B;
        info->sector_count = 35;
        info->size = 0x00200000;
        break;              /* => 2 MB      */

    case (FLASH_WORD_SIZE)SST_ID_xF800A:
        info->flash_id += FLASH_SST800A;
        info->sector_count = 16;
        info->size = 0x00100000;
        break;              /* => 1 MB      */

    case (FLASH_WORD_SIZE)SST_ID_xF160A:
        info->flash_id += FLASH_SST160A;
        info->sector_count = 32;
        info->size = 0x00200000;
        break;              /* => 2 MB      */

    case (FLASH_WORD_SIZE)AMD_ID_F040B:
        info->flash_id += FLASH_AM040;
        info->sector_count = 8;
        info->size = 0x00080000;
        break;              /* => 0.5 MB      */

    default:
        info->flash_id = FLASH_UNKNOWN;
        return (0);         /* => no or unknown flash */

    }

    printf("flash id %lx; sector count %x, size %lx\n", info->flash_id,info->sector_count,info->size);
    /* set up sector start address table */
        if (info->flash_id & FLASH_MAN_SST)
          {
            for (i = 0; i < info->sector_count; i++)
              info->start[i] = base + (i * 0x00010000);
          }
        else
    if (info->flash_id & FLASH_BTYPE) {
        /* set sector offsets for bottom boot block type    */
        info->start[0] = base + 0x00000000;
        info->start[1] = base + 0x00004000;
        info->start[2] = base + 0x00006000;
        info->start[3] = base + 0x00008000;
        for (i = 4; i < info->sector_count; i++) {
            info->start[i] = base + (i * 0x00010000) - 0x00030000;
        }
    } else {
        /* set sector offsets for top boot block type       */
        i = info->sector_count - 1;
        info->start[i--] = base + info->size - 0x00004000;
        info->start[i--] = base + info->size - 0x00006000;
        info->start[i--] = base + info->size - 0x00008000;
        for (; i >= 0; i--) {
            info->start[i] = base + i * 0x00010000;
        }
    }

    /* check for protected sectors */
    for (i = 0; i < info->sector_count; i++) {
        /* read sector protection at sector address, (A7 .. A0) = 0x02 */
        /* D0 = 1 if protected */
        addr2 = (volatile FLASH_WORD_SIZE *)(info->start[i]);
                if (info->flash_id & FLASH_MAN_SST)
                  info->protect[i] = 0;
                else
                  info->protect[i] = addr2[2] & 1;
    }

    /*
     * Prevent writes to uninitialized FLASH.
     */
    if (info->flash_id != FLASH_UNKNOWN) {
       addr2 = (FLASH_WORD_SIZE *)info->start[0];
        *addr2 = (FLASH_WORD_SIZE)0x00F000F0;   /* reset bank */
    }

    return (info->size);
}

#endif


int
flash_erase(flash_info_t *info, int s_first, int s_last)
{
    volatile FLASH_WORD_SIZE *addr = (FLASH_WORD_SIZE *)(info->start[0]);
    int flag, prot, sect, l_sect;
    ulong start, now, last;
    unsigned char sh8b;

    if ((s_first < 0) || (s_first > s_last)) {
        if (info->flash_id == FLASH_UNKNOWN) {
            printf ("- missing\n");
        } else {
            printf ("- no sectors to erase\n");
        }
        return 1;
    }

    if ((info->flash_id == FLASH_UNKNOWN) ||
        (info->flash_id > (FLASH_MAN_STM | FLASH_AMD_COMP))) {
        printf ("Can't erase unknown flash type - aborted\n");
        return 1;
    }

    prot = 0;
    for (sect=s_first; sect<=s_last; ++sect) {
        if (info->protect[sect]) {
            prot++;
        }
    }

    if (prot) {
        printf ("- Warning: %d protected sectors will not be erased!\n",
            prot);
    } else {
        printf ("\n");
    }

    l_sect = -1;

    /* Check the ROM CS */
    if ((info->start[0] >= ROM_CS1_START) && (info->start[0] < ROM_CS0_START))
      sh8b = 3;
    else
      sh8b = 0;

    /* Disable interrupts which might cause a timeout here */
    flag = disable_interrupts();

    addr[ADDR0 << sh8b] = (FLASH_WORD_SIZE)0x00AA00AA;
    addr[ADDR1 << sh8b] = (FLASH_WORD_SIZE)0x00550055;
    addr[ADDR0 << sh8b] = (FLASH_WORD_SIZE)0x00800080;
    addr[ADDR0 << sh8b] = (FLASH_WORD_SIZE)0x00AA00AA;
    addr[ADDR1 << sh8b] = (FLASH_WORD_SIZE)0x00550055;

    /* Start erase on unprotected sectors */
    for (sect = s_first; sect<=s_last; sect++) {
        if (info->protect[sect] == 0) { /* not protected */
            addr = (FLASH_WORD_SIZE *)(info->start[0] + (
				(info->start[sect] - info->start[0]) << sh8b));
                        if (info->flash_id & FLASH_MAN_SST)
                          {
                            addr[ADDR0 << sh8b] = (FLASH_WORD_SIZE)0x00AA00AA;
                            addr[ADDR1 << sh8b] = (FLASH_WORD_SIZE)0x00550055;
                            addr[ADDR0 << sh8b] = (FLASH_WORD_SIZE)0x00800080;
                            addr[ADDR0 << sh8b] = (FLASH_WORD_SIZE)0x00AA00AA;
                            addr[ADDR1 << sh8b] = (FLASH_WORD_SIZE)0x00550055;
                            addr[0] = (FLASH_WORD_SIZE)0x00500050;  /* block erase */
                            udelay(30000);  /* wait 30 ms */
                          }
                        else
                          addr[0] = (FLASH_WORD_SIZE)0x00300030;  /* sector erase */
            l_sect = sect;
        }
    }

    /* re-enable interrupts if necessary */
    if (flag)
        enable_interrupts();

    /* wait at least 80us - let's wait 1 ms */
    udelay (1000);

    /*
     * We wait for the last triggered sector
     */
    if (l_sect < 0)
        goto DONE;

    start = get_timer (0);
    last  = start;
    addr = (FLASH_WORD_SIZE *)(info->start[0] + (
			(info->start[l_sect] - info->start[0]) << sh8b));
    while ((addr[0] & (FLASH_WORD_SIZE)0x00800080) != (FLASH_WORD_SIZE)0x00800080) {
        if ((now = get_timer(start)) > CFG_FLASH_ERASE_TOUT) {
            printf ("Timeout\n");
            return 1;
        }
        /* show that we're waiting */
        if ((now - last) > 1000) {  /* every second */
            serial_putc ('.');
            last = now;
        }
    }

DONE:
    /* reset to read mode */
    addr = (FLASH_WORD_SIZE *)info->start[0];
    addr[0] = (FLASH_WORD_SIZE)0x00F000F0;  /* reset bank */

    printf (" done\n");
    return 0;
}

/*-----------------------------------------------------------------------
 * Copy memory to flash, returns:
 * 0 - OK
 * 1 - write timeout
 * 2 - Flash not erased
 */

int write_buff (flash_info_t *info, uchar *src, ulong addr, ulong cnt)
{
    ulong cp, wp, data;
    int i, l, rc;

    wp = (addr & ~3);   /* get lower word aligned address */

    /*
     * handle unaligned start bytes
     */
    if ((l = addr - wp) != 0) {
        data = 0;
        for (i=0, cp=wp; i<l; ++i, ++cp) {
            data = (data << 8) | (*(uchar *)cp);
        }
        for (; i<4 && cnt>0; ++i) {
            data = (data << 8) | *src++;
            --cnt;
            ++cp;
        }
        for (; cnt==0 && i<4; ++i, ++cp) {
            data = (data << 8) | (*(uchar *)cp);
        }

        if ((rc = write_word(info, wp, data)) != 0) {
            return (rc);
        }
        wp += 4;
    }

    /*
     * handle word aligned part
     */
    while (cnt >= 4) {
        data = 0;
        for (i=0; i<4; ++i) {
            data = (data << 8) | *src++;
        }
        if ((rc = write_word(info, wp, data)) != 0) {
            return (rc);
        }
        wp  += 4;
        cnt -= 4;
    }

    if (cnt == 0) {
        return (0);
    }

    /*
     * handle unaligned tail bytes
     */
    data = 0;
    for (i=0, cp=wp; i<4 && cnt>0; ++i, ++cp) {
        data = (data << 8) | *src++;
        --cnt;
    }
    for (; i<4; ++i, ++cp) {
        data = (data << 8) | (*(uchar *)cp);
    }

    return (write_word(info, wp, data));
}

/*-----------------------------------------------------------------------
 * Write a word to Flash, returns:
 * 0 - OK
 * 1 - write timeout
 * 2 - Flash not erased
 */
static int write_word (flash_info_t *info, ulong dest, ulong data)
{
        volatile FLASH_WORD_SIZE *addr2 = (FLASH_WORD_SIZE *)info->start[0];
        volatile FLASH_WORD_SIZE *dest2;
        volatile FLASH_WORD_SIZE *data2 = (FLASH_WORD_SIZE *)&data;
    ulong start;
    int flag;
        int i;
    unsigned char sh8b;

    /* Check the ROM CS */
    if ((info->start[0] >= ROM_CS1_START) && (info->start[0] < ROM_CS0_START))
      sh8b = 3;
    else
      sh8b = 0;

    dest2 = (FLASH_WORD_SIZE *)(((dest - info->start[0]) << sh8b) +
				info->start[0]);

    /* Check if Flash is (sufficiently) erased */
    if ((*dest2 & (FLASH_WORD_SIZE)data) != (FLASH_WORD_SIZE)data) {
        return (2);
    }
    /* Disable interrupts which might cause a timeout here */
    flag = disable_interrupts();

        for (i=0; i<4/sizeof(FLASH_WORD_SIZE); i++)
          {
            addr2[ADDR0 << sh8b] = (FLASH_WORD_SIZE)0x00AA00AA;
            addr2[ADDR1 << sh8b] = (FLASH_WORD_SIZE)0x00550055;
            addr2[ADDR0 << sh8b] = (FLASH_WORD_SIZE)0x00A000A0;

            dest2[i << sh8b] = data2[i];

            /* re-enable interrupts if necessary */
            if (flag)
              enable_interrupts();

            /* data polling for D7 */
            start = get_timer (0);
            while ((dest2[i << sh8b] & (FLASH_WORD_SIZE)0x00800080) !=
                   (data2[i] & (FLASH_WORD_SIZE)0x00800080)) {
              if (get_timer(start) > CFG_FLASH_WRITE_TOUT) {
                return (1);
              }
            }
          }

    return (0);
}

/*-----------------------------------------------------------------------
 */