flash.c

嵌入式ARM的一些源代码

		info->flash_id += FLASH_AM400B;
		info->sector_count = 11;
		info->size = 0x00100000;
		break;				/* => 1 MB		*/

	case (AMD_ID_LV800T & 0xFFFF):
		info->flash_id += FLASH_AM800T;
		info->sector_count = 19;
		info->size = 0x00200000;
		break;				/* => 2 MB		*/

	case (AMD_ID_LV800B & 0xFFFF):
		info->flash_id += FLASH_AM800B;
		info->sector_count = 19;
		info->size = 0x00200000;
		break;				/* => 2 MB		*/

	case (AMD_ID_LV160T & 0xFFFF):
		info->flash_id += FLASH_AM160T;
		info->sector_count = 35;
		info->size = 0x00400000;
		break;				/* => 4 MB		*/

	case (AMD_ID_LV160B & 0xFFFF):
		info->flash_id += FLASH_AM160B;
		info->sector_count = 35;
		info->size = 0x00400000;
		break;				/* => 4 MB		*/
#if 0	/* enable when device IDs are available */
	case (AMD_ID_LV320T & 0xFFFF):
		info->flash_id += FLASH_AM320T;
		info->sector_count = 67;
		info->size = 0x00800000;
		break;				/* => 8 MB		*/

	case (AMD_ID_LV320B & 0xFFFF):
		info->flash_id += FLASH_AM320B;
		info->sector_count = 67;
		info->size = 0x00800000;
		break;				/* => 8 MB		*/
#endif
	case (SST_ID_xF200A & 0xFFFF):
		info->flash_id += FLASH_SST200A;
		info->sector_count = 64;	/* 39xF200A ID ( 2M = 128K x 16	) */
		info->size = 0x00080000;
		break;
	case (SST_ID_xF400A & 0xFFFF):
		info->flash_id += FLASH_SST400A;
		info->sector_count = 128;	/* 39xF400A ID ( 4M = 256K x 16	) */
		info->size = 0x00100000;
		break;
	case (SST_ID_xF800A & 0xFFFF):
		info->flash_id += FLASH_SST800A;
		info->sector_count = 256;	/* 39xF800A ID ( 8M = 512K x 16	) */
		info->size = 0x00200000;
		break;				/* => 2 MB		*/
	case (STM_ID_x800AB & 0xFFFF):
		info->flash_id += FLASH_STM800AB;
		info->sector_count = 19;
		info->size = 0x00200000;
		break;				/* => 2 MB		*/
	case (MT_ID_28F400_T & 0xFFFF):
		info->flash_id += FLASH_28F400_T;
		info->sector_count = 7;
		info->size = 0x00080000;
		break;				/* => 512 kB		*/
	case (MT_ID_28F400_B & 0xFFFF):
		info->flash_id += FLASH_28F400_B;
		info->sector_count = 7;
		info->size = 0x00080000;
		break;				/* => 512 kB		*/
	default:
		info->flash_id = FLASH_UNKNOWN;
		saddr[0] = 0x00FF;		/* restore read mode */
		return (0);			/* => no or unknown flash */

	}

	if (info->sector_count > CFG_MAX_FLASH_SECT) {
		printf ("** ERROR: sector count %d > max (%d) **\n",
			info->sector_count, CFG_MAX_FLASH_SECT);
		info->sector_count = CFG_MAX_FLASH_SECT;
	}

	saddr[0] = 0x00FF;		/* restore read mode */

	return (info->size);
}


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

void	flash_erase (flash_info_t *info, int s_first, int s_last)
{
	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;
	}

	if ((info->flash_id & FLASH_VENDMASK) != FLASH_MAN_MT) {
		printf ("Can erase only MT flash types - 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");
	}

	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 */
			vu_short *addr = (vu_short *)(info->start[sect]);
			unsigned short status;

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

			*addr = 0x0050;	/* clear status register */
			*addr = 0x0020;	/* erase setup */
			*addr = 0x00D0;	/* erase confirm */

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

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

			while (((status = *addr) & 0x0080) == 0) {
				if ((now=get_timer(start)) > CFG_FLASH_ERASE_TOUT) {
					printf ("Timeout\n");
					*addr = 0x00FF;	/* reset to read mode */
					return;
				}

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

			*addr = 0x00FF;	/* reset to read mode */
		}
	}
	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)) ) {
			return ((info->flash_id == FLASH_UNKNOWN) ? NULL : 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
 * 4 - Flash not identified
 */

#define	FLASH_WIDTH	2	/* flash bus width in bytes */

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

	if (info->flash_id == FLASH_UNKNOWN) {
		return 4;
	}

	wp = (addr & ~(FLASH_WIDTH-1));	/* get lower FLASH_WIDTH 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<FLASH_WIDTH && cnt>0; ++i) {
			data = (data << 8) | *src++;
			--cnt;
			++cp;
		}
		for (; cnt==0 && i<FLASH_WIDTH; ++i, ++cp) {
			data = (data << 8) | (*(uchar *)cp);
		}

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

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

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

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

/*-----------------------------------------------------------------------
 * Write a word to Flash, returns:
 * 0 - OK
 * 1 - write timeout
 * 2 - Flash not erased
 */
static int write_data (flash_info_t *info, ulong dest, ulong data)
{
	vu_short *addr = (vu_short *)dest;
	ushort sdata = (ushort)data;
	ushort status;
	ulong start;
	int flag;

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

	*addr = 0x0040;		/* write setup */
	*addr = sdata;

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

	start = get_timer (0);

	while (((status = *addr) & 0x0080) == 0) {
		if (get_timer(start) > CFG_FLASH_WRITE_TOUT) {
			*addr = 0x00FF;	/* restore read mode */
			return (1);
		}
	}

	*addr = 0x00FF;		/* restore read mode */

	return (0);
}

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