flash.c

嵌入式ARM的一些源代码

		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		*/
#if 0	/* enable when device IDs are available */
	case (FLASH_WORD_SIZE)AMD_ID_LV320T:
		info->flash_id += FLASH_AM320T;
		info->sector_count = 67;
		info->size = 0x00400000;
		break;				/* => 4 MB		*/

	case (FLASH_WORD_SIZE)AMD_ID_LV320B:
		info->flash_id += FLASH_AM320B;
		info->sector_count = 67;
		info->size = 0x00400000;
		break;				/* => 4 MB		*/
#endif
	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		*/

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

	}

	/* set up sector start adress table */
        if ((info->flash_id & FLASH_VENDMASK) == 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 */
#ifdef CONFIG_ADCIOP
		addr2 = (volatile FLASH_WORD_SIZE *)(info->start[i]);
		info->protect[i] = addr2[4] & 1;
#else
		addr2 = (volatile FLASH_WORD_SIZE *)(info->start[i]);
                if ((info->flash_id & FLASH_VENDMASK) == FLASH_MAN_SST)
                  info->protect[i] = 0;
                else
                  info->protect[i] = addr2[2] & 1;
#endif
	}

	/*
	 * Prevent writes to uninitialized FLASH.
	 */
	if (info->flash_id != FLASH_UNKNOWN) {
#if 0 /* test-only */
#ifdef CONFIG_ADCIOP
		addr2 = (volatile unsigned char *)info->start[0];
                addr2[ADDR0] = 0xAA;
                addr2[ADDR1] = 0x55;
                addr2[ADDR0] = 0xF0;  /* reset bank */
#else
		addr2 = (FLASH_WORD_SIZE *)info->start[0];
		*addr2 = (FLASH_WORD_SIZE)0x00F000F0;	/* reset bank */
#endif
#else /* test-only */
		addr2 = (FLASH_WORD_SIZE *)info->start[0];
		*addr2 = (FLASH_WORD_SIZE)0x00F000F0;	/* reset bank */
#endif /* test-only */
	}

	return (info->size);
}


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

void	flash_erase (flash_info_t *info, int s_first, int s_last)
{
	volatile FLASH_WORD_SIZE *addr = (FLASH_WORD_SIZE *)(info->start[0]);
	volatile FLASH_WORD_SIZE *addr2;
	int flag, prot, sect, l_sect;
	ulong start, now, last;

	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;
	}

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

	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;

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

	/* Start erase on unprotected sectors */
	for (sect = s_first; sect<=s_last; sect++) {
		if (info->protect[sect] == 0) {	/* not protected */
		    addr2 = (FLASH_WORD_SIZE *)(info->start[sect]);
                    if ((info->flash_id & FLASH_VENDMASK) == FLASH_MAN_SST) {
                        addr[ADDR0] = (FLASH_WORD_SIZE)0x00AA00AA;
                        addr[ADDR1] = (FLASH_WORD_SIZE)0x00550055;
                        addr[ADDR0] = (FLASH_WORD_SIZE)0x00800080;
                        addr[ADDR0] = (FLASH_WORD_SIZE)0x00AA00AA;
                        addr[ADDR1] = (FLASH_WORD_SIZE)0x00550055;
                        addr2[0] = (FLASH_WORD_SIZE)0x00500050;  /* block erase */
                        udelay(50000);  /* wait 50 ms */
                    } else {
                        addr[ADDR0] = (FLASH_WORD_SIZE)0x00AA00AA;
                        addr[ADDR1] = (FLASH_WORD_SIZE)0x00550055;
                        addr[ADDR0] = (FLASH_WORD_SIZE)0x00800080;
                        addr[ADDR0] = (FLASH_WORD_SIZE)0x00AA00AA;
                        addr[ADDR1] = (FLASH_WORD_SIZE)0x00550055;
                        addr2[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[l_sect]);
	while ((addr[0] & (FLASH_WORD_SIZE)0x00800080) != (FLASH_WORD_SIZE)0x00800080) {
		if ((now = get_timer(start)) > CFG_FLASH_ERASE_TOUT) {
			printf ("Timeout\n");
			return;
		}
		/* show that we're waiting */
		if ((now - last) > 1000) {	/* every second */
			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");
}

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

flash_info_t *addr2info (ulong addr)
{
	flash_info_t *info;
	int i;

	for (i=0, info=&flash_info[0]; i<CFG_MAX_FLASH_BANKS; ++i, ++info) {
		if ((addr >= info->start[0]) &&
		    (addr <= (info->start[0] + info->size - 1)) ) {
			return (info);
		}
	}

	return (NULL);
}

/*-----------------------------------------------------------------------
 * Copy memory to flash.
 * Make sure all target addresses are within Flash bounds,
 * and no protected sectors are hit.
 * Returns:
 * 0 - OK
 * 1 - write timeout
 * 2 - Flash not erased
 * 4 - target range includes protected sectors
 * 8 - target address not in Flash memory
 */
int flash_write (uchar *src, ulong addr, ulong cnt)
{
	int i;
	ulong         end        = addr + cnt - 1;
	flash_info_t *info_first = addr2info (addr);
	flash_info_t *info_last  = addr2info (end );
	flash_info_t *info;

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

	if (!info_first || !info_last) {
		return (8);
	}

	for (info = info_first; info <= info_last; ++info) {
		ulong b_end = info->start[0] + info->size;	/* bank end addr */
		short s_end = info->sector_count - 1;
		for (i=0; i<info->sector_count; ++i) {
			ulong e_addr = (i == s_end) ? b_end : info->start[i + 1];

			if ((end >= info->start[i]) && (addr < e_addr) &&
			    (info->protect[i] != 0) ) {
				return (4);
			}
		}
	}

	/* finally write data to flash */
	for (info = info_first; info <= info_last && cnt>0; ++info) {
		ulong len;
		
		len = info->start[0] + info->size - addr;
		if (len > cnt)
			len = cnt;
		if ((i = write_buff(info, src, addr, len)) != 0) {
			return (i);
		}
		cnt  -= len;
		addr += len;
		src  += len;
	}
	return (0);
}

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

static 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 = (FLASH_WORD_SIZE *)dest;
        volatile FLASH_WORD_SIZE *data2 = (FLASH_WORD_SIZE *)&data;
	ulong start;
	int flag;
        int i;

	/* Check if Flash is (sufficiently) erased */
	if ((*((volatile FLASH_WORD_SIZE *)dest) &
             (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] = (FLASH_WORD_SIZE)0x00AA00AA;
            addr2[ADDR1] = (FLASH_WORD_SIZE)0x00550055;
            addr2[ADDR0] = (FLASH_WORD_SIZE)0x00A000A0;
            
            dest2[i] = data2[i];
            
            /* re-enable interrupts if necessary */
            if (flag)
              enable_interrupts();
            
            /* data polling for D7 */
            start = get_timer (0);
            while ((dest2[i] & (FLASH_WORD_SIZE)0x00800080) !=
                   (data2[i] & (FLASH_WORD_SIZE)0x00800080)) {
              if (get_timer(start) > CFG_FLASH_WRITE_TOUT) {
                return (1);
              }
            }
          }

	return (0);
}

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