flash.c

Linux2.4.27在AT91RM9200下的U-BOOT代码。可以在Redhat9等版本下使用。适合ARM学习者使用。

	addr2[ADDR0] = (FLASH_WORD_SIZE) 0x90;
	value = addr2[0];

	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);
}

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