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。

		break;				/* => 8 MB		*/

	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		*/

	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)SST_ID_xF040:
		info->flash_id += FLASH_SST040;
		info->sector_count = 128;
		info->size = 0x00080000;
		break;				/* => 512KB		*/

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

	}

	/* set up sector start address table */
	if (((info->flash_id & FLASH_VENDMASK) == FLASH_MAN_SST) ||
		(info->flash_id  == FLASH_AM040) ||
		(info->flash_id == FLASH_AMDLV033C) ||
		(info->flash_id == FLASH_AMDLV065D)) {
		ulong sectsize = info->size / info->sector_count;
		for (i = 0; i < info->sector_count; i++)
			info->start[i] = base + (i * sectsize);
	} 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_VENDMASK) == FLASH_MAN_SST)
			info->protect[i] = 0;
		else
			info->protect[i] = addr2[2] & 1;
	}

	/* switch to the read mode */
	if (info->flash_id != FLASH_UNKNOWN) {
		addr2 = (FLASH_WORD_SIZE *)info->start[0];
		*addr2 = (FLASH_WORD_SIZE)0x00F000F0;	/* reset bank */
	}

	return (info->size);
}

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

int 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;
	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 1;
	}

	if (info->flash_id == FLASH_UNKNOWN) {
		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");
	}

	start = get_timer (0);
	last  = start;
	/* 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]);

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

			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;

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

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

			while ((addr2[0] & 0x00800080) !=
				(FLASH_WORD_SIZE) 0x00800080) {
				if ((now=get_timer(start)) >
					   CFG_FLASH_ERASE_TOUT) {
					printf ("Timeout\n");
					addr[0] = (FLASH_WORD_SIZE)0x00F000F0;
					return 1;
				}

				/* show that we're waiting */
				if ((now - last) > 1000) {  /* every second  */
					putc ('.');
					last = now;
				}
			}

			addr[0] = (FLASH_WORD_SIZE)0x00F000F0;
		}
	}

	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 = (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 ulong *)dest) & data) != data) {
		printf("dest = %08lx, *dest = %08lx, data = %08lx\n",
			dest, *(volatile ulong *)dest, data);
		return 2;
	}

	for (i=0; i < 4/sizeof(FLASH_WORD_SIZE); i++) {
		/* Disable interrupts which might cause a timeout here */
		flag = disable_interrupts();

		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] & 0x00800080) != (data2[i] & 0x00800080)) {
			if (get_timer(start) > CFG_FLASH_WRITE_TOUT) {
				addr2[0] = (FLASH_WORD_SIZE)0x00F000F0;
				return (1);
			}
		}
	}

	addr2[0] = (FLASH_WORD_SIZE)0x00F000F0;

	return (0);
}

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