board/iphase4539/flash.c - platform/external/u-boot - Gitiles

 /*
  * (C) Copyright 2001
  * Josh Huber <huber@mclx.com>, Mission Critical Linux, Inc.
  *
  * (C) Copyright 2002
  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
  *
  * Adapted for Interphase 4539 by Wolfgang Grandegger <wg@denx.de>.
  *
  * 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 <config.h>
 #include <common.h>
 #include <flash.h>
 #include <asm/io.h>

 flash_info_t	flash_info[CFG_MAX_FLASH_BANKS];

 extern int hwc_flash_size(void);
 static ulong flash_get_size (u32 addr, flash_info_t *info);
 static int flash_get_offsets (u32 base, flash_info_t *info);
 static int write_word (flash_info_t *info, ulong dest, ulong data);
 static void flash_reset (u32 addr);

 #define out8(a,v) *(volatile unsigned char*)(a) = v
 #define in8(a)	  *(volatile unsigned char*)(a)
 #define in32(a)	  *(volatile unsigned long*)(a)
 #define iobarrier_rw() eieio()

 unsigned long flash_init (void)
 {
 	unsigned int i;
 	unsigned long flash_size = 0;
 	unsigned long bank_size;
 	unsigned int bank = 0;

 	/* Init: no FLASHes known */
 	for (i=0; i < CFG_MAX_FLASH_BANKS; ++i) {
 		flash_info[i].flash_id = FLASH_UNKNOWN;
 		flash_info[i].sector_count = 0;
 		flash_info[i].size = 0;
 	}

 	/* Initialise the BOOT Flash */
 	if (bank == CFG_MAX_FLASH_BANKS) {
 		puts ("Warning: not all Flashes are initialised !");
 		return flash_size;
 	}

 	bank_size = flash_get_size (CFG_FLASH_BASE, flash_info + bank);
 	if (bank_size) {
 #if CFG_MONITOR_BASE >= CFG_FLASH_BASE && \
     CFG_MONITOR_BASE < CFG_FLASH_BASE + CFG_MAX_FLASH_SIZE
 		/* monitor protection ON by default */
 		flash_protect(FLAG_PROTECT_SET,
 			      CFG_MONITOR_BASE,
 			      CFG_MONITOR_BASE + monitor_flash_len - 1,
 			      flash_info + bank);
 #endif

 #ifdef CONFIG_ENV_IS_IN_FLASH
 		/* ENV protection ON by default */
 		flash_protect(FLAG_PROTECT_SET,
 			      CFG_ENV_ADDR,
 			      CFG_ENV_ADDR + CFG_ENV_SECT_SIZE - 1,
 			      flash_info + bank);
 #endif

 		/* HWC protection ON by default */
 		flash_protect(FLAG_PROTECT_SET,
 			      CFG_FLASH_BASE,
 			      CFG_FLASH_BASE + 0x10000 - 1,
 			      flash_info + bank);

 		flash_size += bank_size;
 		bank++;
 	} else {
 		puts ("Warning: the BOOT Flash is not initialised !");
 	}

 	return flash_size;
 }

 /*
  * The following code cannot be run from FLASH!
  */
 static ulong flash_get_size (u32 addr, flash_info_t *info)
 {
 	volatile uchar value;
 #if 0
 	int i;
 #endif

 	/* Write auto select command: read Manufacturer ID */
 	out8(addr + 0x0555, 0xAA);
 	iobarrier_rw();
 	udelay(10);
 	out8(addr + 0x02AA, 0x55);
 	iobarrier_rw();
 	udelay(10);
 	out8(addr + 0x0555, 0x90);
 	iobarrier_rw();
 	udelay(10);

 	value = in8(addr);
 	iobarrier_rw();
 	udelay(10);
 	switch (value | (value << 16)) {
 	case AMD_MANUFACT:
 		info->flash_id = FLASH_MAN_AMD;
 		break;

 	case FUJ_MANUFACT:
 		info->flash_id = FLASH_MAN_FUJ;
 		break;

 	default:
 		info->flash_id = FLASH_UNKNOWN;
 		flash_reset (addr);
 		return 0;
 	}

 	value = in8(addr + 1);			/* device ID		*/
 	iobarrier_rw();

 	switch (value) {
 	case AMD_ID_LV033C:
 		info->flash_id += FLASH_AM033C;
 		info->size = hwc_flash_size();
 		if (info->size > CFG_MAX_FLASH_SIZE) {
 			printf("U-Boot supports only %d MB\n",
 			       CFG_MAX_FLASH_SIZE);
 			info->size = CFG_MAX_FLASH_SIZE;
 		}
 		info->sector_count = info->size / 0x10000;
 		break;				/* => 4 MB		*/

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

 	}

 	if (!flash_get_offsets (addr, info)) {
 		flash_reset (addr);
 		return 0;
 	}

 #if 0
 	/* 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 */
 		value = in8(info->start[i] + 2);
 		iobarrier_rw();
 		info->protect[i] = (value & 1) != 0;
 	}
 #endif

 	/*
 	 * Reset bank to read mode
 	 */
 	flash_reset (addr);

 	return (info->size);
 }

 static int flash_get_offsets (u32 base, flash_info_t *info)
 {
 	unsigned int i, size;

 	switch (info->flash_id & FLASH_TYPEMASK) {
 	case FLASH_AM033C:
 		/* set sector offsets for uniform sector type	*/
 		size = info->size / info->sector_count;
 		for (i = 0; i < info->sector_count; i++) {
 			info->start[i] = base + i * size;
 		}
 		break;
 	default:
 		return 0;
 	}

 	return 1;
 }

 int flash_erase (flash_info_t *info, int s_first, int s_last)
 {
 	volatile u32 addr = info->start[0];
 	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 1;
 	}

 	if (info->flash_id == FLASH_UNKNOWN ||
 	    info->flash_id > FLASH_AMD_COMP) {
 		printf ("Can't erase unknown flash type %08lx - aborted\n",
 			info->flash_id);
 		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();

 	out8(addr + 0x555, 0xAA);
 	iobarrier_rw();
 	out8(addr + 0x2AA, 0x55);
 	iobarrier_rw();
 	out8(addr + 0x555, 0x80);
 	iobarrier_rw();
 	out8(addr + 0x555, 0xAA);
 	iobarrier_rw();
 	out8(addr + 0x2AA, 0x55);
 	iobarrier_rw();

 	/* Start erase on unprotected sectors */
 	for (sect = s_first; sect<=s_last; sect++) {
 		if (info->protect[sect] == 0) {	/* not protected */
 			addr = info->start[sect];
 			out8(addr, 0x30);
 			iobarrier_rw();
 			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 = info->start[l_sect];
 	while ((in8(addr) & 0x80) != 0x80) {
 		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;
 		}
 		iobarrier_rw();
 	}

 DONE:
 	/* reset to read mode */
 	flash_reset (info->start[0]);

 	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 u32 addr = info->start[0];
 	ulong start;
 	int flag, i;

 	/* Check if Flash is (sufficiently) erased */
 	if ((in32(dest) & data) != data) {
 		return (2);
 	}
 	/* Disable interrupts which might cause a timeout here */
 	flag = disable_interrupts();

 	/* first, perform an unlock bypass command to speed up flash writes */
 	out8(addr + 0x555, 0xAA);
 	iobarrier_rw();
 	out8(addr + 0x2AA, 0x55);
 	iobarrier_rw();
 	out8(addr + 0x555, 0x20);
 	iobarrier_rw();

 	/* write each byte out */
 	for (i = 0; i < 4; i++) {
 		char *data_ch = (char *)&data;
 		out8(addr, 0xA0);
 		iobarrier_rw();
 		out8(dest+i, data_ch[i]);
 		iobarrier_rw();
 		udelay(10); /* XXX */
 	}

 	/* we're done, now do an unlock bypass reset */
 	out8(addr, 0x90);
 	iobarrier_rw();
 	out8(addr, 0x00);
 	iobarrier_rw();

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

 	/* data polling for D7 */
 	start = get_timer (0);
 	while ((in32(dest) & 0x80808080) != (data & 0x80808080)) {
 		if (get_timer(start) > CFG_FLASH_WRITE_TOUT) {
 			return (1);
 		}
 		iobarrier_rw();
 	}

 	flash_reset (addr);

 	return (0);
 }

 /*
  * Reset bank to read mode
  */
 static void flash_reset (u32 addr)
 {
 	out8(addr, 0xF0);	/* reset bank */
 	iobarrier_rw();
 }

 void flash_print_info (flash_info_t *info)
 {
 	int i;

 	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_BM:	printf ("BRIGHT MICRO ");	break;
 	default:		printf ("Unknown Vendor ");	break;
 	}

 	switch (info->flash_id & FLASH_TYPEMASK) {
 	case FLASH_AM033C:	printf ("AM29LV033C (32 Mbit, uniform sectors)\n");
 				break;
 	default:		printf ("Unknown Chip Type\n");
 				break;
 	}

 	if (info->size % 0x100000 == 0) {
 		printf ("  Size: %ld MB in %d Sectors\n",
 			info->size / 0x100000, info->sector_count);
 	}
 	else if (info->size % 0x400 == 0) {
 		printf ("  Size: %ld KB in %d Sectors\n",
 			info->size / 0x400, info->sector_count);
 	}
 	else {
 		printf ("  Size: %ld B in %d Sectors\n",
 			info->size, info->sector_count);
 	}

 	printf ("  Sector Start Addresses:");
 	for (i=0; i<info->sector_count; ++i) {
 		if ((i % 5) == 0)
 			printf ("\n   ");
 		printf (" %08lX%s",
 			info->start[i],
 			info->protect[i] ? " (RO)" : "     "
 		);
 	}
 	printf ("\n");
 }
	/*
	* (C) Copyright 2001
	* Josh Huber <huber@mclx.com>, Mission Critical Linux, Inc.
	*
	* (C) Copyright 2002
	* Wolfgang Denk, DENX Software Engineering, wd@denx.de.
	*
	* Adapted for Interphase 4539 by Wolfgang Grandegger <wg@denx.de>.
	*
	* 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 <config.h>
	#include <common.h>
	#include <flash.h>
	#include <asm/io.h>

	flash_info_t flash_info[CFG_MAX_FLASH_BANKS];

	extern int hwc_flash_size(void);
	static ulong flash_get_size (u32 addr, flash_info_t *info);
	static int flash_get_offsets (u32 base, flash_info_t *info);
	static int write_word (flash_info_t *info, ulong dest, ulong data);
	static void flash_reset (u32 addr);

	#define out8(a,v) (volatile unsigned char)(a) = v
	#define in8(a) (volatile unsigned char)(a)
	#define in32(a) (volatile unsigned long)(a)
	#define iobarrier_rw() eieio()

	unsigned long flash_init (void)
	{
	unsigned int i;
	unsigned long flash_size = 0;
	unsigned long bank_size;
	unsigned int bank = 0;

	/* Init: no FLASHes known */
	for (i=0; i < CFG_MAX_FLASH_BANKS; ++i) {
	flash_info[i].flash_id = FLASH_UNKNOWN;
	flash_info[i].sector_count = 0;
	flash_info[i].size = 0;
	}

	/* Initialise the BOOT Flash */
	if (bank == CFG_MAX_FLASH_BANKS) {
	puts ("Warning: not all Flashes are initialised !");
	return flash_size;
	}

	bank_size = flash_get_size (CFG_FLASH_BASE, flash_info + bank);
	if (bank_size) {
	#if CFG_MONITOR_BASE >= CFG_FLASH_BASE && \
	CFG_MONITOR_BASE < CFG_FLASH_BASE + CFG_MAX_FLASH_SIZE
	/* monitor protection ON by default */
	flash_protect(FLAG_PROTECT_SET,
	CFG_MONITOR_BASE,
	CFG_MONITOR_BASE + monitor_flash_len - 1,
	flash_info + bank);
	#endif

	#ifdef CONFIG_ENV_IS_IN_FLASH
	/* ENV protection ON by default */
	flash_protect(FLAG_PROTECT_SET,
	CFG_ENV_ADDR,
	CFG_ENV_ADDR + CFG_ENV_SECT_SIZE - 1,
	flash_info + bank);
	#endif

	/* HWC protection ON by default */
	flash_protect(FLAG_PROTECT_SET,
	CFG_FLASH_BASE,
	CFG_FLASH_BASE + 0x10000 - 1,
	flash_info + bank);

	flash_size += bank_size;
	bank++;
	} else {
	puts ("Warning: the BOOT Flash is not initialised !");
	}

	return flash_size;
	}

	/*
	* The following code cannot be run from FLASH!
	*/
	static ulong flash_get_size (u32 addr, flash_info_t *info)
	{
	volatile uchar value;
	#if 0
	int i;
	#endif

	/* Write auto select command: read Manufacturer ID */
	out8(addr + 0x0555, 0xAA);
	iobarrier_rw();
	udelay(10);
	out8(addr + 0x02AA, 0x55);
	iobarrier_rw();
	udelay(10);
	out8(addr + 0x0555, 0x90);
	iobarrier_rw();
	udelay(10);

	value = in8(addr);
	iobarrier_rw();
	udelay(10);
	switch (value \| (value << 16)) {
	case AMD_MANUFACT:
	info->flash_id = FLASH_MAN_AMD;
	break;

	case FUJ_MANUFACT:
	info->flash_id = FLASH_MAN_FUJ;
	break;

	default:
	info->flash_id = FLASH_UNKNOWN;
	flash_reset (addr);
	return 0;
	}

	value = in8(addr + 1); /* device ID */
	iobarrier_rw();

	switch (value) {
	case AMD_ID_LV033C:
	info->flash_id += FLASH_AM033C;
	info->size = hwc_flash_size();
	if (info->size > CFG_MAX_FLASH_SIZE) {
	printf("U-Boot supports only %d MB\n",
	CFG_MAX_FLASH_SIZE);
	info->size = CFG_MAX_FLASH_SIZE;
	}
	info->sector_count = info->size / 0x10000;
	break; /* => 4 MB */

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

	}

	if (!flash_get_offsets (addr, info)) {
	flash_reset (addr);
	return 0;
	}

	#if 0
	/* 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 */
	value = in8(info->start[i] + 2);
	iobarrier_rw();
	info->protect[i] = (value & 1) != 0;
	}
	#endif

	/*
	* Reset bank to read mode
	*/
	flash_reset (addr);

	return (info->size);
	}

	static int flash_get_offsets (u32 base, flash_info_t *info)
	{
	unsigned int i, size;

	switch (info->flash_id & FLASH_TYPEMASK) {
	case FLASH_AM033C:
	/* set sector offsets for uniform sector type */
	size = info->size / info->sector_count;
	for (i = 0; i < info->sector_count; i++) {
	info->start[i] = base + i * size;
	}
	break;
	default:
	return 0;
	}

	return 1;
	}

	int flash_erase (flash_info_t *info, int s_first, int s_last)
	{
	volatile u32 addr = info->start[0];
	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 1;
	}

	if (info->flash_id == FLASH_UNKNOWN \|\|
	info->flash_id > FLASH_AMD_COMP) {
	printf ("Can't erase unknown flash type %08lx - aborted\n",
	info->flash_id);
	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();

	out8(addr + 0x555, 0xAA);
	iobarrier_rw();
	out8(addr + 0x2AA, 0x55);
	iobarrier_rw();
	out8(addr + 0x555, 0x80);
	iobarrier_rw();
	out8(addr + 0x555, 0xAA);
	iobarrier_rw();
	out8(addr + 0x2AA, 0x55);
	iobarrier_rw();

	/* Start erase on unprotected sectors */
	for (sect = s_first; sect<=s_last; sect++) {
	if (info->protect[sect] == 0) { /* not protected */
	addr = info->start[sect];
	out8(addr, 0x30);
	iobarrier_rw();
	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 = info->start[l_sect];
	while ((in8(addr) & 0x80) != 0x80) {
	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;
	}
	iobarrier_rw();
	}

	DONE:
	/* reset to read mode */
	flash_reset (info->start[0]);

	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 u32 addr = info->start[0];
	ulong start;
	int flag, i;

	/* Check if Flash is (sufficiently) erased */
	if ((in32(dest) & data) != data) {
	return (2);
	}
	/* Disable interrupts which might cause a timeout here */
	flag = disable_interrupts();

	/* first, perform an unlock bypass command to speed up flash writes */
	out8(addr + 0x555, 0xAA);
	iobarrier_rw();
	out8(addr + 0x2AA, 0x55);
	iobarrier_rw();
	out8(addr + 0x555, 0x20);
	iobarrier_rw();

	/* write each byte out */
	for (i = 0; i < 4; i++) {
	char data_ch = (char )&data;
	out8(addr, 0xA0);
	iobarrier_rw();
	out8(dest+i, data_ch[i]);
	iobarrier_rw();
	udelay(10); /* XXX */
	}

	/* we're done, now do an unlock bypass reset */
	out8(addr, 0x90);
	iobarrier_rw();
	out8(addr, 0x00);
	iobarrier_rw();

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

	/* data polling for D7 */
	start = get_timer (0);
	while ((in32(dest) & 0x80808080) != (data & 0x80808080)) {
	if (get_timer(start) > CFG_FLASH_WRITE_TOUT) {
	return (1);
	}
	iobarrier_rw();
	}

	flash_reset (addr);

	return (0);
	}

	/*
	* Reset bank to read mode
	*/
	static void flash_reset (u32 addr)
	{
	out8(addr, 0xF0); /* reset bank */
	iobarrier_rw();
	}

	void flash_print_info (flash_info_t *info)
	{
	int i;

	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_BM: printf ("BRIGHT MICRO "); break;
	default: printf ("Unknown Vendor "); break;
	}

	switch (info->flash_id & FLASH_TYPEMASK) {
	case FLASH_AM033C: printf ("AM29LV033C (32 Mbit, uniform sectors)\n");
	break;
	default: printf ("Unknown Chip Type\n");
	break;
	}

	if (info->size % 0x100000 == 0) {
	printf (" Size: %ld MB in %d Sectors\n",
	info->size / 0x100000, info->sector_count);
	}
	else if (info->size % 0x400 == 0) {
	printf (" Size: %ld KB in %d Sectors\n",
	info->size / 0x400, info->sector_count);
	}
	else {
	printf (" Size: %ld B in %d Sectors\n",
	info->size, info->sector_count);
	}

	printf (" Sector Start Addresses:");
	for (i=0; i<info->sector_count; ++i) {
	if ((i % 5) == 0)
	printf ("\n ");
	printf (" %08lX%s",
	info->start[i],
	info->protect[i] ? " (RO)" : " "
	);
	}
	printf ("\n");
	}