board/esd/common/flash.c - u-boot - Git at Google

 /*
  * (C) Copyright 2001
  * Stefan Roese, esd gmbh germany, stefan.roese@esd-electronics.com
  *
  * See file CREDITS for list of people who contributed to this
  * project.
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License as
  * published by the Free Software Foundation; either version 2 of
  * the License, or (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  * MA 02111-1307 USA
  */

 #include <common.h>
 #include <ppc4xx.h>
 #include <asm/processor.h>

 flash_info_t	flash_info[CFG_MAX_FLASH_BANKS]; /* info for FLASH chips	*/

 /*-----------------------------------------------------------------------
  * Functions
  */
 static int write_word (flash_info_t *info, ulong dest, ulong data);

 /*-----------------------------------------------------------------------
  */
 static void flash_get_offsets (ulong base, flash_info_t *info)
 {
 	int i;
 	short n;

 	/* set up sector start address table */
 	if (((info->flash_id & FLASH_VENDMASK) == FLASH_MAN_SST) ||
 	    ((info->flash_id & FLASH_TYPEMASK) == FLASH_AM640U)) {
 	    for (i = 0; i < info->sector_count; i++)
 		info->start[i] = base + (i * 0x00010000);
 	} else if (((info->flash_id & FLASH_TYPEMASK) == FLASH_AMDL322B) ||
 		   ((info->flash_id & FLASH_TYPEMASK) == FLASH_AMDL323B) ||
 		   ((info->flash_id & FLASH_TYPEMASK) == FLASH_AM320B) ||
 		   ((info->flash_id & FLASH_TYPEMASK) == FLASH_AMDL324B)) {
 		/* set sector offsets for bottom boot block type	*/
 		for (i=0; i<8; ++i) {		/*  8 x 8k boot sectors	*/
 			info->start[i] = base;
 			base += 8 << 10;
 		}
 		while (i < info->sector_count) {	/* 64k regular sectors	*/
 			info->start[i] = base;
 			base += 64 << 10;
 			++i;
 		}
 	} else if (((info->flash_id & FLASH_TYPEMASK) == FLASH_AMDL322T) ||
 		   ((info->flash_id & FLASH_TYPEMASK) == FLASH_AMDL323T) ||
 		   ((info->flash_id & FLASH_TYPEMASK) == FLASH_AM320T) ||
 		   ((info->flash_id & FLASH_TYPEMASK) == FLASH_AMDL324T)) {
 		/* set sector offsets for top boot block type		*/
 		base += info->size;
 		i = info->sector_count;
 		for (n=0; n<8; ++n) {		/*  8 x 8k boot sectors	*/
 			base -= 8 << 10;
 			--i;
 			info->start[i] = base;
 		}
 		while (i > 0) {			/* 64k regular sectors	*/
 			base -= 64 << 10;
 			--i;
 			info->start[i] = base;
 		}
 	} 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;
 		}
 	    }
 	}
 }

 /*-----------------------------------------------------------------------
  */
 void flash_print_info  (flash_info_t *info)
 {
 	int i;
 	int k;
 	int size;
 	int erased;
 	volatile unsigned long *flash;

 	if (info->flash_id == FLASH_UNKNOWN) {
 		printf ("missing or unknown FLASH type\n");
 		return;
 	}

 	switch (info->flash_id & FLASH_VENDMASK) {
 	case FLASH_MAN_AMD:	printf ("AMD ");		break;
 	case FLASH_MAN_FUJ:	printf ("FUJITSU ");		break;
 	case FLASH_MAN_SST:	printf ("SST ");		break;
 	case FLASH_MAN_EXCEL:	printf ("Excel Semiconductor "); break;
 	default:		printf ("Unknown Vendor ");	break;
 	}

 	switch (info->flash_id & FLASH_TYPEMASK) {
 	case FLASH_AM400B:	printf ("AM29LV400B (4 Mbit, bottom boot sect)\n");
 				break;
 	case FLASH_AM400T:	printf ("AM29LV400T (4 Mbit, top boot sector)\n");
 				break;
 	case FLASH_AM800B:	printf ("AM29LV800B (8 Mbit, bottom boot sect)\n");
 				break;
 	case FLASH_AM800T:	printf ("AM29LV800T (8 Mbit, top boot sector)\n");
 				break;
 	case FLASH_AM160B:	printf ("AM29LV160B (16 Mbit, bottom boot sect)\n");
 				break;
 	case FLASH_AM160T:	printf ("AM29LV160T (16 Mbit, top boot sector)\n");
 				break;
 	case FLASH_AM320T:	printf ("AM29LV320T (32 M, top sector)\n");
 				break;
 	case FLASH_AM320B:	printf ("AM29LV320B (32 M, bottom sector)\n");
 				break;
 	case FLASH_AMDL322T:	printf ("AM29DL322T (32 M, top sector)\n");
 				break;
 	case FLASH_AMDL322B:	printf ("AM29DL322B (32 M, bottom sector)\n");
 				break;
 	case FLASH_AMDL323T:	printf ("AM29DL323T (32 M, top sector)\n");
 				break;
 	case FLASH_AMDL323B:	printf ("AM29DL323B (32 M, bottom sector)\n");
 				break;
 	case FLASH_AM640U:	printf ("AM29LV640D (64 M, uniform sector)\n");
 				break;
 	case FLASH_SST800A:	printf ("SST39LF/VF800 (8 Mbit, uniform sector size)\n");
 				break;
 	case FLASH_SST160A:	printf ("SST39LF/VF160 (16 Mbit, uniform sector size)\n");
 				break;
 	case FLASH_SST320:	printf ("SST39LF/VF320 (32 Mbit, uniform sector size)\n");
 				break;
 	case FLASH_SST640:	printf ("SST39LF/VF640 (64 Mbit, uniform sector size)\n");
 				break;
 	default:		printf ("Unknown Chip Type\n");
 				break;
 	}

 	printf ("  Size: %ld MB in %d Sectors\n",
 		info->size >> 20, info->sector_count);

 	printf ("  Sector Start Addresses:");
 	for (i=0; i<info->sector_count; ++i) {
 #ifdef CFG_FLASH_EMPTY_INFO
 		/*
 		 * Check if whole sector is erased
 		 */
 		if (i != (info->sector_count-1))
 		  size = info->start[i+1] - info->start[i];
 		else
 		  size = info->start[0] + info->size - info->start[i];
 		erased = 1;
 		flash = (volatile unsigned long *)info->start[i];
 		size = size >> 2;        /* divide by 4 for longword access */
 		for (k=0; k<size; k++)
 		  {
 		    if (*flash++ != 0xffffffff)
 		      {
 			erased = 0;
 			break;
 		      }
 		  }

 		if ((i % 5) == 0)
 			printf ("\n   ");
 		/* print empty and read-only info */
 		printf (" %08lX%s%s",
 			info->start[i],
 			erased ? " E" : "  ",
 			info->protect[i] ? "RO " : "   ");
 #else
 		if ((i % 5) == 0)
 			printf ("\n   ");
 		printf (" %08lX%s",
 			info->start[i],
 			info->protect[i] ? " (RO)" : "     ");
 #endif

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

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


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

 /*
  * The following code cannot be run from FLASH!
  */
 static ulong flash_get_size (vu_long *addr, flash_info_t *info)
 {
 	short i;
 	short n;
 	CFG_FLASH_WORD_SIZE value;
 	ulong base = (ulong)addr;
 	volatile CFG_FLASH_WORD_SIZE *addr2 = (CFG_FLASH_WORD_SIZE *)addr;

 	/* Write auto select command: read Manufacturer ID */
 	addr2[CFG_FLASH_ADDR0] = (CFG_FLASH_WORD_SIZE)0x00AA00AA;
 	addr2[CFG_FLASH_ADDR1] = (CFG_FLASH_WORD_SIZE)0x00550055;
 	addr2[CFG_FLASH_ADDR0] = (CFG_FLASH_WORD_SIZE)0x00900090;

 	value = addr2[CFG_FLASH_READ0];

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

 	value = addr2[CFG_FLASH_READ1];		/* device ID		*/

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

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

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

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

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

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

 	case (CFG_FLASH_WORD_SIZE)AMD_ID_LV320T:
 		info->flash_id += FLASH_AM320T;
 		info->sector_count = 71;
 		info->size = 0x00400000;  break;	/* => 4 MB	*/

 	case (CFG_FLASH_WORD_SIZE)AMD_ID_LV320B:
 		info->flash_id += FLASH_AM320B;
 		info->sector_count = 71;
 		info->size = 0x00400000;  break;	/* => 4 MB	*/

 	case (CFG_FLASH_WORD_SIZE)AMD_ID_DL322T:
 		info->flash_id += FLASH_AMDL322T;
 		info->sector_count = 71;
 		info->size = 0x00400000;  break;	/* => 4 MB	*/

 	case (CFG_FLASH_WORD_SIZE)AMD_ID_DL322B:
 		info->flash_id += FLASH_AMDL322B;
 		info->sector_count = 71;
 		info->size = 0x00400000;  break;	/* => 4 MB	*/

 	case (CFG_FLASH_WORD_SIZE)AMD_ID_DL323T:
 		info->flash_id += FLASH_AMDL323T;
 		info->sector_count = 71;
 		info->size = 0x00400000;  break;	/* => 4 MB	*/

 	case (CFG_FLASH_WORD_SIZE)AMD_ID_DL323B:
 		info->flash_id += FLASH_AMDL323B;
 		info->sector_count = 71;
 		info->size = 0x00400000;  break;	/* => 4 MB	*/

 	case (CFG_FLASH_WORD_SIZE)AMD_ID_LV640U:
 		info->flash_id += FLASH_AM640U;
 		info->sector_count = 128;
 		info->size = 0x00800000;  break;	/* => 8 MB	*/

 #if !(defined(CONFIG_ADCIOP) || defined(CONFIG_DASA_SIM))
 	case (CFG_FLASH_WORD_SIZE)SST_ID_xF800A:
 		info->flash_id += FLASH_SST800A;
 		info->sector_count = 16;
 		info->size = 0x00100000;
 		break;				/* => 1 MB		*/

 	case (CFG_FLASH_WORD_SIZE)SST_ID_xF160A:
 	case (CFG_FLASH_WORD_SIZE)SST_ID_xF1601:
 	case (CFG_FLASH_WORD_SIZE)SST_ID_xF1602:
 		info->flash_id += FLASH_SST160A;
 		info->sector_count = 32;
 		info->size = 0x00200000;
 		break;				/* => 2 MB		*/

 	case (CFG_FLASH_WORD_SIZE)SST_ID_xF3201:
 	case (CFG_FLASH_WORD_SIZE)SST_ID_xF3202:
 		info->flash_id += FLASH_SST320;
 		info->sector_count = 64;
 		info->size = 0x00400000;
 		break;				/* => 4 MB		*/

 	case (CFG_FLASH_WORD_SIZE)SST_ID_xF6401:
 	case (CFG_FLASH_WORD_SIZE)SST_ID_xF6402:
 		info->flash_id += FLASH_SST640;
 		info->sector_count = 128;
 		info->size = 0x00800000;
 		break;				/* => 8 MB		*/
 #endif

 	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_TYPEMASK) == FLASH_AM640U)) {
 	    for (i = 0; i < info->sector_count; i++)
 		info->start[i] = base + (i * 0x00010000);
 	} else if (((info->flash_id & FLASH_TYPEMASK) == FLASH_AMDL322B) ||
 		   ((info->flash_id & FLASH_TYPEMASK) == FLASH_AMDL323B) ||
 		   ((info->flash_id & FLASH_TYPEMASK) == FLASH_AM320B) ||
 		   ((info->flash_id & FLASH_TYPEMASK) == FLASH_AMDL324B)) {
 		/* set sector offsets for bottom boot block type	*/
 		for (i=0; i<8; ++i) {		/*  8 x 8k boot sectors	*/
 			info->start[i] = base;
 			base += 8 << 10;
 		}
 		while (i < info->sector_count) {	/* 64k regular sectors	*/
 			info->start[i] = base;
 			base += 64 << 10;
 			++i;
 		}
 	} else if (((info->flash_id & FLASH_TYPEMASK) == FLASH_AMDL322T) ||
 		   ((info->flash_id & FLASH_TYPEMASK) == FLASH_AMDL323T) ||
 		   ((info->flash_id & FLASH_TYPEMASK) == FLASH_AM320T) ||
 		   ((info->flash_id & FLASH_TYPEMASK) == FLASH_AMDL324T)) {
 		/* set sector offsets for top boot block type		*/
 		base += info->size;
 		i = info->sector_count;
 		for (n=0; n<8; ++n) {		/*  8 x 8k boot sectors	*/
 			base -= 8 << 10;
 			--i;
 			info->start[i] = base;
 		}
 		while (i > 0) {			/* 64k regular sectors	*/
 			base -= 64 << 10;
 			--i;
 			info->start[i] = base;
 		}
 	} 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 CFG_FLASH_WORD_SIZE *)(info->start[i]);
 		if ((info->flash_id & FLASH_VENDMASK) != FLASH_MAN_AMD)
 		  info->protect[i] = 0;
 		else
 		  info->protect[i] = addr2[CFG_FLASH_READ2] & 1;
 	}

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

 	return (info->size);
 }


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

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

 	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");
 	}

 	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 = (CFG_FLASH_WORD_SIZE *)(info->start[sect]);
 		    if ((info->flash_id & FLASH_VENDMASK) == FLASH_MAN_SST) {
 			addr[CFG_FLASH_ADDR0] = (CFG_FLASH_WORD_SIZE)0x00AA00AA;
 			addr[CFG_FLASH_ADDR1] = (CFG_FLASH_WORD_SIZE)0x00550055;
 			addr[CFG_FLASH_ADDR0] = (CFG_FLASH_WORD_SIZE)0x00800080;
 			addr[CFG_FLASH_ADDR0] = (CFG_FLASH_WORD_SIZE)0x00AA00AA;
 			addr[CFG_FLASH_ADDR1] = (CFG_FLASH_WORD_SIZE)0x00550055;
 			addr2[0] = (CFG_FLASH_WORD_SIZE)0x00500050;  /* block erase */
 			for (i=0; i<50; i++)
 			  udelay(1000);  /* wait 1 ms */
 		    } else {
 			if (sect == s_first) {
 			    addr[CFG_FLASH_ADDR0] = (CFG_FLASH_WORD_SIZE)0x00AA00AA;
 			    addr[CFG_FLASH_ADDR1] = (CFG_FLASH_WORD_SIZE)0x00550055;
 			    addr[CFG_FLASH_ADDR0] = (CFG_FLASH_WORD_SIZE)0x00800080;
 			    addr[CFG_FLASH_ADDR0] = (CFG_FLASH_WORD_SIZE)0x00AA00AA;
 			    addr[CFG_FLASH_ADDR1] = (CFG_FLASH_WORD_SIZE)0x00550055;
 			}
 			addr2[0] = (CFG_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 = (CFG_FLASH_WORD_SIZE *)(info->start[l_sect]);
 	while ((addr[0] & (CFG_FLASH_WORD_SIZE)0x00800080) != (CFG_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 */
 			putc ('.');
 			last = now;
 		}
 	}

 DONE:
 	/* reset to read mode */
 	addr = (CFG_FLASH_WORD_SIZE *)info->start[0];
 	addr[0] = (CFG_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 CFG_FLASH_WORD_SIZE *addr2 = (CFG_FLASH_WORD_SIZE *)(info->start[0]);
 	volatile CFG_FLASH_WORD_SIZE *dest2 = (CFG_FLASH_WORD_SIZE *)dest;
 	volatile CFG_FLASH_WORD_SIZE *data2 = (CFG_FLASH_WORD_SIZE *)&data;
 	ulong start;
 	int flag;
 	int i;

 	/* Check if Flash is (sufficiently) erased */
 	if ((*((vu_long *)dest) & data) != data) {
 		return (2);
 	}

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

 	for (i=0; i<4/sizeof(CFG_FLASH_WORD_SIZE); i++)
 	  {
 	    addr2[CFG_FLASH_ADDR0] = (CFG_FLASH_WORD_SIZE)0x00AA00AA;
 	    addr2[CFG_FLASH_ADDR1] = (CFG_FLASH_WORD_SIZE)0x00550055;
 	    addr2[CFG_FLASH_ADDR0] = (CFG_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] & (CFG_FLASH_WORD_SIZE)0x00800080) !=
 		   (data2[i] & (CFG_FLASH_WORD_SIZE)0x00800080)) {
 	      if (get_timer(start) > CFG_FLASH_WRITE_TOUT) {
 		return (1);
 	      }
 	    }
 	  }

 	return (0);
 }

 /*-----------------------------------------------------------------------
  */
	/*
	* (C) Copyright 2001
	* Stefan Roese, esd gmbh germany, stefan.roese@esd-electronics.com
	*
	* See file CREDITS for list of people who contributed to this
	* project.
	*
	* This program is free software; you can redistribute it and/or
	* modify it under the terms of the GNU General Public License as
	* published by the Free Software Foundation; either version 2 of
	* the License, or (at your option) any later version.
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program; if not, write to the Free Software
	* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
	* MA 02111-1307 USA
	*/

	#include <common.h>
	#include <ppc4xx.h>
	#include <asm/processor.h>

	flash_info_t flash_info[CFG_MAX_FLASH_BANKS]; /* info for FLASH chips */

	/*-----------------------------------------------------------------------
	* Functions
	*/
	static int write_word (flash_info_t *info, ulong dest, ulong data);

	/*-----------------------------------------------------------------------
	*/
	static void flash_get_offsets (ulong base, flash_info_t *info)
	{
	int i;
	short n;

	/* set up sector start address table */
	if (((info->flash_id & FLASH_VENDMASK) == FLASH_MAN_SST) \|\|
	((info->flash_id & FLASH_TYPEMASK) == FLASH_AM640U)) {
	for (i = 0; i < info->sector_count; i++)
	info->start[i] = base + (i * 0x00010000);
	} else if (((info->flash_id & FLASH_TYPEMASK) == FLASH_AMDL322B) \|\|
	((info->flash_id & FLASH_TYPEMASK) == FLASH_AMDL323B) \|\|
	((info->flash_id & FLASH_TYPEMASK) == FLASH_AM320B) \|\|
	((info->flash_id & FLASH_TYPEMASK) == FLASH_AMDL324B)) {
	/* set sector offsets for bottom boot block type */
	for (i=0; i<8; ++i) { /* 8 x 8k boot sectors */
	info->start[i] = base;
	base += 8 << 10;
	}
	while (i < info->sector_count) { /* 64k regular sectors */
	info->start[i] = base;
	base += 64 << 10;
	++i;
	}
	} else if (((info->flash_id & FLASH_TYPEMASK) == FLASH_AMDL322T) \|\|
	((info->flash_id & FLASH_TYPEMASK) == FLASH_AMDL323T) \|\|
	((info->flash_id & FLASH_TYPEMASK) == FLASH_AM320T) \|\|
	((info->flash_id & FLASH_TYPEMASK) == FLASH_AMDL324T)) {
	/* set sector offsets for top boot block type */
	base += info->size;
	i = info->sector_count;
	for (n=0; n<8; ++n) { /* 8 x 8k boot sectors */
	base -= 8 << 10;
	--i;
	info->start[i] = base;
	}
	while (i > 0) { /* 64k regular sectors */
	base -= 64 << 10;
	--i;
	info->start[i] = base;
	}
	} 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;
	}
	}
	}
	}

	/*-----------------------------------------------------------------------
	*/
	void flash_print_info (flash_info_t *info)
	{
	int i;
	int k;
	int size;
	int erased;
	volatile unsigned long *flash;

	if (info->flash_id == FLASH_UNKNOWN) {
	printf ("missing or unknown FLASH type\n");
	return;
	}

	switch (info->flash_id & FLASH_VENDMASK) {
	case FLASH_MAN_AMD: printf ("AMD "); break;
	case FLASH_MAN_FUJ: printf ("FUJITSU "); break;
	case FLASH_MAN_SST: printf ("SST "); break;
	case FLASH_MAN_EXCEL: printf ("Excel Semiconductor "); break;
	default: printf ("Unknown Vendor "); break;
	}

	switch (info->flash_id & FLASH_TYPEMASK) {
	case FLASH_AM400B: printf ("AM29LV400B (4 Mbit, bottom boot sect)\n");
	break;
	case FLASH_AM400T: printf ("AM29LV400T (4 Mbit, top boot sector)\n");
	break;
	case FLASH_AM800B: printf ("AM29LV800B (8 Mbit, bottom boot sect)\n");
	break;
	case FLASH_AM800T: printf ("AM29LV800T (8 Mbit, top boot sector)\n");
	break;
	case FLASH_AM160B: printf ("AM29LV160B (16 Mbit, bottom boot sect)\n");
	break;
	case FLASH_AM160T: printf ("AM29LV160T (16 Mbit, top boot sector)\n");
	break;
	case FLASH_AM320T: printf ("AM29LV320T (32 M, top sector)\n");
	break;
	case FLASH_AM320B: printf ("AM29LV320B (32 M, bottom sector)\n");
	break;
	case FLASH_AMDL322T: printf ("AM29DL322T (32 M, top sector)\n");
	break;
	case FLASH_AMDL322B: printf ("AM29DL322B (32 M, bottom sector)\n");
	break;
	case FLASH_AMDL323T: printf ("AM29DL323T (32 M, top sector)\n");
	break;
	case FLASH_AMDL323B: printf ("AM29DL323B (32 M, bottom sector)\n");
	break;
	case FLASH_AM640U: printf ("AM29LV640D (64 M, uniform sector)\n");
	break;
	case FLASH_SST800A: printf ("SST39LF/VF800 (8 Mbit, uniform sector size)\n");
	break;
	case FLASH_SST160A: printf ("SST39LF/VF160 (16 Mbit, uniform sector size)\n");
	break;
	case FLASH_SST320: printf ("SST39LF/VF320 (32 Mbit, uniform sector size)\n");
	break;
	case FLASH_SST640: printf ("SST39LF/VF640 (64 Mbit, uniform sector size)\n");
	break;
	default: printf ("Unknown Chip Type\n");
	break;
	}

	printf (" Size: %ld MB in %d Sectors\n",
	info->size >> 20, info->sector_count);

	printf (" Sector Start Addresses:");
	for (i=0; i<info->sector_count; ++i) {
	#ifdef CFG_FLASH_EMPTY_INFO
	/*
	* Check if whole sector is erased
	*/
	if (i != (info->sector_count-1))
	size = info->start[i+1] - info->start[i];
	else
	size = info->start[0] + info->size - info->start[i];
	erased = 1;
	flash = (volatile unsigned long *)info->start[i];
	size = size >> 2; /* divide by 4 for longword access */
	for (k=0; k<size; k++)
	{
	if (*flash++ != 0xffffffff)
	{
	erased = 0;
	break;
	}
	}

	if ((i % 5) == 0)
	printf ("\n ");
	/* print empty and read-only info */
	printf (" %08lX%s%s",
	info->start[i],
	erased ? " E" : " ",
	info->protect[i] ? "RO " : " ");
	#else
	if ((i % 5) == 0)
	printf ("\n ");
	printf (" %08lX%s",
	info->start[i],
	info->protect[i] ? " (RO)" : " ");
	#endif

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

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


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

	/*
	* The following code cannot be run from FLASH!
	*/
	static ulong flash_get_size (vu_long addr, flash_info_t info)
	{
	short i;
	short n;
	CFG_FLASH_WORD_SIZE value;
	ulong base = (ulong)addr;
	volatile CFG_FLASH_WORD_SIZE addr2 = (CFG_FLASH_WORD_SIZE )addr;

	/* Write auto select command: read Manufacturer ID */
	addr2[CFG_FLASH_ADDR0] = (CFG_FLASH_WORD_SIZE)0x00AA00AA;
	addr2[CFG_FLASH_ADDR1] = (CFG_FLASH_WORD_SIZE)0x00550055;
	addr2[CFG_FLASH_ADDR0] = (CFG_FLASH_WORD_SIZE)0x00900090;

	value = addr2[CFG_FLASH_READ0];

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

	value = addr2[CFG_FLASH_READ1]; /* device ID */

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

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

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

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

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

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

	case (CFG_FLASH_WORD_SIZE)AMD_ID_LV320T:
	info->flash_id += FLASH_AM320T;
	info->sector_count = 71;
	info->size = 0x00400000; break; /* => 4 MB */

	case (CFG_FLASH_WORD_SIZE)AMD_ID_LV320B:
	info->flash_id += FLASH_AM320B;
	info->sector_count = 71;
	info->size = 0x00400000; break; /* => 4 MB */

	case (CFG_FLASH_WORD_SIZE)AMD_ID_DL322T:
	info->flash_id += FLASH_AMDL322T;
	info->sector_count = 71;
	info->size = 0x00400000; break; /* => 4 MB */

	case (CFG_FLASH_WORD_SIZE)AMD_ID_DL322B:
	info->flash_id += FLASH_AMDL322B;
	info->sector_count = 71;
	info->size = 0x00400000; break; /* => 4 MB */

	case (CFG_FLASH_WORD_SIZE)AMD_ID_DL323T:
	info->flash_id += FLASH_AMDL323T;
	info->sector_count = 71;
	info->size = 0x00400000; break; /* => 4 MB */

	case (CFG_FLASH_WORD_SIZE)AMD_ID_DL323B:
	info->flash_id += FLASH_AMDL323B;
	info->sector_count = 71;
	info->size = 0x00400000; break; /* => 4 MB */

	case (CFG_FLASH_WORD_SIZE)AMD_ID_LV640U:
	info->flash_id += FLASH_AM640U;
	info->sector_count = 128;
	info->size = 0x00800000; break; /* => 8 MB */

	#if !(defined(CONFIG_ADCIOP) \|\| defined(CONFIG_DASA_SIM))
	case (CFG_FLASH_WORD_SIZE)SST_ID_xF800A:
	info->flash_id += FLASH_SST800A;
	info->sector_count = 16;
	info->size = 0x00100000;
	break; /* => 1 MB */

	case (CFG_FLASH_WORD_SIZE)SST_ID_xF160A:
	case (CFG_FLASH_WORD_SIZE)SST_ID_xF1601:
	case (CFG_FLASH_WORD_SIZE)SST_ID_xF1602:
	info->flash_id += FLASH_SST160A;
	info->sector_count = 32;
	info->size = 0x00200000;
	break; /* => 2 MB */

	case (CFG_FLASH_WORD_SIZE)SST_ID_xF3201:
	case (CFG_FLASH_WORD_SIZE)SST_ID_xF3202:
	info->flash_id += FLASH_SST320;
	info->sector_count = 64;
	info->size = 0x00400000;
	break; /* => 4 MB */

	case (CFG_FLASH_WORD_SIZE)SST_ID_xF6401:
	case (CFG_FLASH_WORD_SIZE)SST_ID_xF6402:
	info->flash_id += FLASH_SST640;
	info->sector_count = 128;
	info->size = 0x00800000;
	break; /* => 8 MB */
	#endif

	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_TYPEMASK) == FLASH_AM640U)) {
	for (i = 0; i < info->sector_count; i++)
	info->start[i] = base + (i * 0x00010000);
	} else if (((info->flash_id & FLASH_TYPEMASK) == FLASH_AMDL322B) \|\|
	((info->flash_id & FLASH_TYPEMASK) == FLASH_AMDL323B) \|\|
	((info->flash_id & FLASH_TYPEMASK) == FLASH_AM320B) \|\|
	((info->flash_id & FLASH_TYPEMASK) == FLASH_AMDL324B)) {
	/* set sector offsets for bottom boot block type */
	for (i=0; i<8; ++i) { /* 8 x 8k boot sectors */
	info->start[i] = base;
	base += 8 << 10;
	}
	while (i < info->sector_count) { /* 64k regular sectors */
	info->start[i] = base;
	base += 64 << 10;
	++i;
	}
	} else if (((info->flash_id & FLASH_TYPEMASK) == FLASH_AMDL322T) \|\|
	((info->flash_id & FLASH_TYPEMASK) == FLASH_AMDL323T) \|\|
	((info->flash_id & FLASH_TYPEMASK) == FLASH_AM320T) \|\|
	((info->flash_id & FLASH_TYPEMASK) == FLASH_AMDL324T)) {
	/* set sector offsets for top boot block type */
	base += info->size;
	i = info->sector_count;
	for (n=0; n<8; ++n) { /* 8 x 8k boot sectors */
	base -= 8 << 10;
	--i;
	info->start[i] = base;
	}
	while (i > 0) { /* 64k regular sectors */
	base -= 64 << 10;
	--i;
	info->start[i] = base;
	}
	} 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 CFG_FLASH_WORD_SIZE *)(info->start[i]);
	if ((info->flash_id & FLASH_VENDMASK) != FLASH_MAN_AMD)
	info->protect[i] = 0;
	else
	info->protect[i] = addr2[CFG_FLASH_READ2] & 1;
	}

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

	return (info->size);
	}


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

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

	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");
	}

	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 = (CFG_FLASH_WORD_SIZE *)(info->start[sect]);
	if ((info->flash_id & FLASH_VENDMASK) == FLASH_MAN_SST) {
	addr[CFG_FLASH_ADDR0] = (CFG_FLASH_WORD_SIZE)0x00AA00AA;
	addr[CFG_FLASH_ADDR1] = (CFG_FLASH_WORD_SIZE)0x00550055;
	addr[CFG_FLASH_ADDR0] = (CFG_FLASH_WORD_SIZE)0x00800080;
	addr[CFG_FLASH_ADDR0] = (CFG_FLASH_WORD_SIZE)0x00AA00AA;
	addr[CFG_FLASH_ADDR1] = (CFG_FLASH_WORD_SIZE)0x00550055;
	addr2[0] = (CFG_FLASH_WORD_SIZE)0x00500050; /* block erase */
	for (i=0; i<50; i++)
	udelay(1000); /* wait 1 ms */
	} else {
	if (sect == s_first) {
	addr[CFG_FLASH_ADDR0] = (CFG_FLASH_WORD_SIZE)0x00AA00AA;
	addr[CFG_FLASH_ADDR1] = (CFG_FLASH_WORD_SIZE)0x00550055;
	addr[CFG_FLASH_ADDR0] = (CFG_FLASH_WORD_SIZE)0x00800080;
	addr[CFG_FLASH_ADDR0] = (CFG_FLASH_WORD_SIZE)0x00AA00AA;
	addr[CFG_FLASH_ADDR1] = (CFG_FLASH_WORD_SIZE)0x00550055;
	}
	addr2[0] = (CFG_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 = (CFG_FLASH_WORD_SIZE *)(info->start[l_sect]);
	while ((addr[0] & (CFG_FLASH_WORD_SIZE)0x00800080) != (CFG_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 */
	putc ('.');
	last = now;
	}
	}

	DONE:
	/* reset to read mode */
	addr = (CFG_FLASH_WORD_SIZE *)info->start[0];
	addr[0] = (CFG_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 CFG_FLASH_WORD_SIZE addr2 = (CFG_FLASH_WORD_SIZE )(info->start[0]);
	volatile CFG_FLASH_WORD_SIZE dest2 = (CFG_FLASH_WORD_SIZE )dest;
	volatile CFG_FLASH_WORD_SIZE data2 = (CFG_FLASH_WORD_SIZE )&data;
	ulong start;
	int flag;
	int i;

	/* Check if Flash is (sufficiently) erased */
	if ((((vu_long )dest) & data) != data) {
	return (2);
	}

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

	for (i=0; i<4/sizeof(CFG_FLASH_WORD_SIZE); i++)
	{
	addr2[CFG_FLASH_ADDR0] = (CFG_FLASH_WORD_SIZE)0x00AA00AA;
	addr2[CFG_FLASH_ADDR1] = (CFG_FLASH_WORD_SIZE)0x00550055;
	addr2[CFG_FLASH_ADDR0] = (CFG_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] & (CFG_FLASH_WORD_SIZE)0x00800080) !=
	(data2[i] & (CFG_FLASH_WORD_SIZE)0x00800080)) {
	if (get_timer(start) > CFG_FLASH_WRITE_TOUT) {
	return (1);
	}
	}
	}

	return (0);
	}

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