board/gw8260/flash.c - github/trini/u-boot - Gitiles

 /*
  * (C) Copyright 2000
  * Marius Groeger <mgroeger@sysgo.de>
  * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
  *
  * (C) Copyright 2000, 2001
  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
  *
  * (C) Copyright 2001
  * Advent Networks, Inc. <http://www.adventnetworks.com>
  * Oliver Brown <oliverb@alumni.utexas.net>
  *
  *--------------------------------------------------------------------
  * 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
  */

 /*********************************************************************/
 /* DESCRIPTION:
  *   This file contains the flash routines for the GW8260 board.
  *
  *
  *
  * MODULE DEPENDENCY:
  *   None
  *
  *
  * RESTRICTIONS/LIMITATIONS:
  *
  *   Only supports the following flash devices:
  *     AMD 29F080B
  *     AMD 29F016D
  *
  * Copyright (c) 2001, Advent Networks, Inc.
  *
  */
 /*********************************************************************/

 #include <common.h>
 #include <mpc8260.h>

 flash_info_t flash_info[CONFIG_SYS_MAX_FLASH_BANKS];

 static ulong flash_get_size (vu_long *addr, flash_info_t *info);
 static int write_word (flash_info_t *info, ulong dest, ulong data);

 /*********************************************************************/
 /*		      functions					     */
 /*********************************************************************/

 /*
  * NAME: flash_init() -	 initializes flash banks
  *
  * DESCRIPTION:
  *   This function initializes the flash bank(s).
  *
  * RETURNS:
  *   The size in bytes of the flash
  *
  * RESTRICTIONS/LIMITATIONS:
  *
  *
  */
 unsigned long flash_init(void)
 {
 	int i;

 	/* Init: no FLASHes known */
 	for (i = 0; i < CONFIG_SYS_MAX_FLASH_BANKS; ++i)
 		flash_info[i].flash_id = FLASH_UNKNOWN;

 	/* for now, only support the 4 MB Flash SIMM */
 	(void)flash_get_size((vu_long *) CONFIG_SYS_FLASH0_BASE,
 			      &flash_info[0]);
 	/*
 	 * protect monitor and environment sectors
 	 */
 #if CONFIG_SYS_MONITOR_BASE >= CONFIG_SYS_FLASH0_BASE
 	flash_protect(FLAG_PROTECT_SET,
 		      CONFIG_SYS_MONITOR_BASE,
 		      CONFIG_SYS_MONITOR_BASE + monitor_flash_len - 1,
 		      &flash_info[0]);
 #endif

 #if defined(CONFIG_ENV_IS_IN_FLASH) && defined(CONFIG_ENV_ADDR)
 #ifndef CONFIG_ENV_SIZE
 #define CONFIG_ENV_SIZE	CONFIG_ENV_SECT_SIZE
 #endif
 	flash_protect(FLAG_PROTECT_SET,
 		      CONFIG_ENV_ADDR,
 		      CONFIG_ENV_ADDR + CONFIG_ENV_SIZE - 1, &flash_info[0]);
 #endif

 	return CONFIG_SYS_FLASH0_SIZE * 1024 * 1024;	/*size */
 }

 /*********************************************************************/
 /* NAME: flash_print_info() - prints flash imformation		     */
 /*								     */
 /* DESCRIPTION:							     */
 /*   This function prints the flash information.		     */
 /*								     */
 /* INPUTS:							     */
 /*   flash_info_t *info - flash information structure		     */
 /*								     */
 /* OUTPUTS:							     */
 /*   Displays flash information to console			     */
 /*								     */
 /* RETURNS:							     */
 /*   None							     */
 /*								     */
 /* RESTRICTIONS/LIMITATIONS:					     */
 /*								     */
 /*								     */
 /*********************************************************************/
 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 >> 16) & 0xff) {
     case 0x1:
 	printf ("AMD ");
 	break;
     default:
 	printf ("Unknown Vendor ");
 	break;
     }

     switch (info->flash_id & FLASH_TYPEMASK) {
     case AMD_ID_F040B:
 	printf ("AM29F040B (4 Mbit)\n");
 	break;
     case AMD_ID_F080B:
 	printf ("AM29F080B (8 Mbit)\n");
 	break;
     case AMD_ID_F016D:
 	printf ("AM29F016D (16 Mbit)\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) {
 	if ((i % 5) == 0)
 	    printf ("\n	  ");
 	printf (" %08lX%s",
 		info->start[i],
 		info->protect[i] ? " (RO)" : "	   "
 	    );
     }
     printf ("\n");
     return;
 }

 /*********************************************************************/
 /*   The following code cannot be run from FLASH!		     */
 /*********************************************************************/

 /*********************************************************************/
 /* NAME: flash_get_size() - detects the flash size		     */
 /*								     */
 /* DESCRIPTION:							     */
 /*   1) Reads vendor ID and devices ID from the flash devices.	     */
 /*   2) Initializes flash info struct.				     */
 /*   3) Return the flash size					     */
 /*								     */
 /* INPUTS:							     */
 /*   vu_long *addr	- pointer to start of flash		     */
 /*   flash_info_t *info - flash information structure		     */
 /*								     */
 /* OUTPUTS:							     */
 /*   None							     */
 /*								     */
 /* RETURNS:							     */
 /*   Size of the flash in bytes, or 0 if device id is unknown.	     */
 /*								     */
 /* RESTRICTIONS/LIMITATIONS:					     */
 /*   Only supports the following devices:			     */
 /*     AM29F080D						     */
 /*     AM29F016D						     */
 /*								     */
 /*********************************************************************/
 static ulong flash_get_size (vu_long *addr, flash_info_t *info)
 {
     short i;
     vu_long vendor, devid;
     ulong base = (ulong)addr;

     /*printf("addr   = %08lx\n", (unsigned long)addr); */

     /* Reset and Write auto select command: read Manufacturer ID */
     addr[0x0000] = 0xf0f0f0f0;
     addr[0x0555] = 0xAAAAAAAA;
     addr[0x02AA] = 0x55555555;
     addr[0x0555] = 0x90909090;
     udelay (1000);

     vendor = addr[0];
     /*printf("vendor = %08lx\n", vendor); */
     if (vendor != 0x01010101) {
 	info->size = 0;
 	goto out;
     }

     devid = addr[1];
     /*printf("devid  = %08lx\n", devid); */

     if ((devid & 0xff) == AMD_ID_F080B) {
 	info->flash_id	   = (vendor & 0xff) << 16 | AMD_ID_F080B;
 	/* we have 16 sectors with 64KB each x 4 */
 	info->sector_count = 16;
 	info->size	   = 4 * info->sector_count * 64*1024;
     } else if ((devid & 0xff) == AMD_ID_F016D){
 	info->flash_id	   = (vendor & 0xff) << 16 | AMD_ID_F016D;
 	/* we have 32 sectors with 64KB each x 4 */
 	info->sector_count = 32;
 	info->size	   = 4 * info->sector_count * 64*1024;
     } else {
 	info->size = 0;
 	goto out;
     }
     /*printf("sector count = %08x\n", info->sector_count); */
     /* check for protected sectors */
     for (i = 0; i < info->sector_count; i++) {
 	/* sector base address */
 	info->start[i] = base + i * (info->size / info->sector_count);
 	/* read sector protection at sector address, (A7 .. A0) = 0x02 */
 	/* D0 = 1 if protected */
 	addr = (volatile unsigned long *)(info->start[i]);
 	info->protect[i] = addr[2] & 1;
     }

     /* reset command */
     addr = (vu_long *)info->start[0];

   out:
     addr[0] = 0xf0f0f0f0;

     /*printf("size = %08x\n", info->size); */
     return info->size;
 }

 /*********************************************************************/
 /* NAME: flash_erase() - erases flash by sector			     */
 /*								     */
 /* DESCRIPTION:							     */
 /*   This function erases flash sectors starting for s_first to	     */
 /*   s_last.							     */
 /*								     */
 /* INPUTS:							     */
 /*   flash_info_t *info - flash information structure		     */
 /*   int s_first - first sector to erase			     */
 /*   int s_last	 - last sector to erase				     */
 /*								     */
 /* OUTPUTS:							     */
 /*   None							     */
 /*								     */
 /* RETURNS:							     */
 /*   Returns 0 for success, 1 for failure.			     */
 /*								     */
 /* RESTRICTIONS/LIMITATIONS:					     */
 /*								     */
 /*********************************************************************/
 int flash_erase (flash_info_t *info, int s_first, int s_last)
 {
     vu_long *addr = (vu_long*)(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;
     }

     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();

     addr[0x0555] = 0xAAAAAAAA;
     addr[0x02AA] = 0x55555555;
     addr[0x0555] = 0x80808080;
     addr[0x0555] = 0xAAAAAAAA;
     addr[0x02AA] = 0x55555555;
     udelay (100);

     /* Start erase on unprotected sectors */
     for (sect = s_first; sect <= s_last; sect++) {
 	if (info->protect[sect] == 0) { /* not protected */
 	    addr = (vu_long*)(info->start[sect]);
 	    addr[0] = 0x30303030;
 	    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 = (vu_long*)(info->start[l_sect]);
     while ((addr[0] & 0x80808080) != 0x80808080) {
 	if ((now = get_timer(start)) > CONFIG_SYS_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 = (volatile unsigned long *)info->start[0];
     addr[0] = 0xF0F0F0F0;   /* reset bank */

     printf (" done\n");
     return 0;
 }

 /*********************************************************************/
 /* NAME: write_buff() - writes a buffer to flash		     */
 /*								     */
 /* DESCRIPTION:							     */
 /*   This function copies a buffer, *src, to flash.		     */
 /*								     */
 /* INPUTS:							     */
 /*  flash_info_t *info - flash information structure		     */
 /*  uchar *src - pointer to buffer to write to flash		     */
 /*  ulong addr - address to start write at			     */
 /*  ulong cnt - number of bytes to write to flash		     */
 /*								     */
 /* OUTPUTS:							     */
 /*   None							     */
 /*								     */
 /* RETURNS:							     */
 /*   0 - OK							     */
 /*   1 - write timeout						     */
 /*   2 - Flash not erased					     */
 /*								     */
 /* RESTRICTIONS/LIMITATIONS:					     */
 /*								     */
 /*********************************************************************/
 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));
 }

 /*********************************************************************/
 /* NAME: write_word() - writes a word to flash			     */
 /*								     */
 /* DESCRIPTION:							     */
 /*   This writes a single word to flash.			     */
 /*								     */
 /* INPUTS:							     */
 /*  flash_info_t *info - flash information structure		     */
 /*  ulong dest - address to write				     */
 /*  ulong data - data to write					     */
 /*								     */
 /* OUTPUTS:							     */
 /*   None							     */
 /*								     */
 /* RETURNS:							     */
 /*   0 - OK							     */
 /*   1 - write timeout						     */
 /*   2 - Flash not erased					     */
 /*								     */
 /* RESTRICTIONS/LIMITATIONS:					     */
 /*								     */
 /*********************************************************************/
 static int write_word (flash_info_t *info, ulong dest, ulong data)
 {
     vu_long *addr = (vu_long*)(info->start[0]);
     ulong start;
     int flag;

     /* 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();

     addr[0x0555] = 0xAAAAAAAA;
     addr[0x02AA] = 0x55555555;
     addr[0x0555] = 0xA0A0A0A0;

     *((vu_long *)dest) = data;

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

     /* data polling for D7 */
     start = get_timer (0);
     while ((*((vu_long *)dest) & 0x80808080) != (data & 0x80808080)) {
 	if (get_timer(start) > CONFIG_SYS_FLASH_WRITE_TOUT) {
 	    return (1);
 	}
     }
     return (0);
 }
 /*********************************************************************/
 /*			   End of flash.c			     */
 /*********************************************************************/
	/*
	* (C) Copyright 2000
	* Marius Groeger <mgroeger@sysgo.de>
	* Sysgo Real-Time Solutions, GmbH <www.elinos.com>
	*
	* (C) Copyright 2000, 2001
	* Wolfgang Denk, DENX Software Engineering, wd@denx.de.
	*
	* (C) Copyright 2001
	* Advent Networks, Inc. <http://www.adventnetworks.com>
	* Oliver Brown <oliverb@alumni.utexas.net>
	*
	*--------------------------------------------------------------------
	* 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
	*/

	/*********************************************************************/
	/* DESCRIPTION:
	* This file contains the flash routines for the GW8260 board.
	*
	*
	*
	* MODULE DEPENDENCY:
	* None
	*
	*
	* RESTRICTIONS/LIMITATIONS:
	*
	* Only supports the following flash devices:
	* AMD 29F080B
	* AMD 29F016D
	*
	* Copyright (c) 2001, Advent Networks, Inc.
	*
	*/
	/*********************************************************************/

	#include <common.h>
	#include <mpc8260.h>

	flash_info_t flash_info[CONFIG_SYS_MAX_FLASH_BANKS];

	static ulong flash_get_size (vu_long addr, flash_info_t info);
	static int write_word (flash_info_t *info, ulong dest, ulong data);

	/*********************************************************************/
	/* functions */
	/*********************************************************************/

	/*
	* NAME: flash_init() - initializes flash banks
	*
	* DESCRIPTION:
	* This function initializes the flash bank(s).
	*
	* RETURNS:
	* The size in bytes of the flash
	*
	* RESTRICTIONS/LIMITATIONS:
	*
	*
	*/
	unsigned long flash_init(void)
	{
	int i;

	/* Init: no FLASHes known */
	for (i = 0; i < CONFIG_SYS_MAX_FLASH_BANKS; ++i)
	flash_info[i].flash_id = FLASH_UNKNOWN;

	/* for now, only support the 4 MB Flash SIMM */
	(void)flash_get_size((vu_long *) CONFIG_SYS_FLASH0_BASE,
	&flash_info[0]);
	/*
	* protect monitor and environment sectors
	*/
	#if CONFIG_SYS_MONITOR_BASE >= CONFIG_SYS_FLASH0_BASE
	flash_protect(FLAG_PROTECT_SET,
	CONFIG_SYS_MONITOR_BASE,
	CONFIG_SYS_MONITOR_BASE + monitor_flash_len - 1,
	&flash_info[0]);
	#endif

	#if defined(CONFIG_ENV_IS_IN_FLASH) && defined(CONFIG_ENV_ADDR)
	#ifndef CONFIG_ENV_SIZE
	#define CONFIG_ENV_SIZE CONFIG_ENV_SECT_SIZE
	#endif
	flash_protect(FLAG_PROTECT_SET,
	CONFIG_ENV_ADDR,
	CONFIG_ENV_ADDR + CONFIG_ENV_SIZE - 1, &flash_info[0]);
	#endif

	return CONFIG_SYS_FLASH0_SIZE * 1024 * 1024; /size /
	}

	/*********************************************************************/
	/* NAME: flash_print_info() - prints flash imformation */
	/* */
	/* DESCRIPTION: */
	/* This function prints the flash information. */
	/* */
	/* INPUTS: */
	/* flash_info_t info - flash information structure /
	/* */
	/* OUTPUTS: */
	/* Displays flash information to console */
	/* */
	/* RETURNS: */
	/* None */
	/* */
	/* RESTRICTIONS/LIMITATIONS: */
	/* */
	/* */
	/*********************************************************************/
	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 >> 16) & 0xff) {
	case 0x1:
	printf ("AMD ");
	break;
	default:
	printf ("Unknown Vendor ");
	break;
	}

	switch (info->flash_id & FLASH_TYPEMASK) {
	case AMD_ID_F040B:
	printf ("AM29F040B (4 Mbit)\n");
	break;
	case AMD_ID_F080B:
	printf ("AM29F080B (8 Mbit)\n");
	break;
	case AMD_ID_F016D:
	printf ("AM29F016D (16 Mbit)\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) {
	if ((i % 5) == 0)
	printf ("\n ");
	printf (" %08lX%s",
	info->start[i],
	info->protect[i] ? " (RO)" : " "
	);
	}
	printf ("\n");
	return;
	}

	/*********************************************************************/
	/* The following code cannot be run from FLASH! */
	/*********************************************************************/

	/*********************************************************************/
	/* NAME: flash_get_size() - detects the flash size */
	/* */
	/* DESCRIPTION: */
	/* 1) Reads vendor ID and devices ID from the flash devices. */
	/* 2) Initializes flash info struct. */
	/* 3) Return the flash size */
	/* */
	/* INPUTS: */
	/* vu_long addr - pointer to start of flash /
	/* flash_info_t info - flash information structure /
	/* */
	/* OUTPUTS: */
	/* None */
	/* */
	/* RETURNS: */
	/* Size of the flash in bytes, or 0 if device id is unknown. */
	/* */
	/* RESTRICTIONS/LIMITATIONS: */
	/* Only supports the following devices: */
	/* AM29F080D */
	/* AM29F016D */
	/* */
	/*********************************************************************/
	static ulong flash_get_size (vu_long addr, flash_info_t info)
	{
	short i;
	vu_long vendor, devid;
	ulong base = (ulong)addr;

	/printf("addr = %08lx\n", (unsigned long)addr); /

	/* Reset and Write auto select command: read Manufacturer ID */
	addr[0x0000] = 0xf0f0f0f0;
	addr[0x0555] = 0xAAAAAAAA;
	addr[0x02AA] = 0x55555555;
	addr[0x0555] = 0x90909090;
	udelay (1000);

	vendor = addr[0];
	/printf("vendor = %08lx\n", vendor); /
	if (vendor != 0x01010101) {
	info->size = 0;
	goto out;
	}

	devid = addr[1];
	/printf("devid = %08lx\n", devid); /

	if ((devid & 0xff) == AMD_ID_F080B) {
	info->flash_id = (vendor & 0xff) << 16 \| AMD_ID_F080B;
	/* we have 16 sectors with 64KB each x 4 */
	info->sector_count = 16;
	info->size = 4 * info->sector_count * 64*1024;
	} else if ((devid & 0xff) == AMD_ID_F016D){
	info->flash_id = (vendor & 0xff) << 16 \| AMD_ID_F016D;
	/* we have 32 sectors with 64KB each x 4 */
	info->sector_count = 32;
	info->size = 4 * info->sector_count * 64*1024;
	} else {
	info->size = 0;
	goto out;
	}
	/printf("sector count = %08x\n", info->sector_count); /
	/* check for protected sectors */
	for (i = 0; i < info->sector_count; i++) {
	/* sector base address */
	info->start[i] = base + i * (info->size / info->sector_count);
	/* read sector protection at sector address, (A7 .. A0) = 0x02 */
	/* D0 = 1 if protected */
	addr = (volatile unsigned long *)(info->start[i]);
	info->protect[i] = addr[2] & 1;
	}

	/* reset command */
	addr = (vu_long *)info->start[0];

	out:
	addr[0] = 0xf0f0f0f0;

	/printf("size = %08x\n", info->size); /
	return info->size;
	}

	/*********************************************************************/
	/* NAME: flash_erase() - erases flash by sector */
	/* */
	/* DESCRIPTION: */
	/* This function erases flash sectors starting for s_first to */
	/* s_last. */
	/* */
	/* INPUTS: */
	/* flash_info_t info - flash information structure /
	/* int s_first - first sector to erase */
	/* int s_last - last sector to erase */
	/* */
	/* OUTPUTS: */
	/* None */
	/* */
	/* RETURNS: */
	/* Returns 0 for success, 1 for failure. */
	/* */
	/* RESTRICTIONS/LIMITATIONS: */
	/* */
	/*********************************************************************/
	int flash_erase (flash_info_t *info, int s_first, int s_last)
	{
	vu_long addr = (vu_long)(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;
	}

	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();

	addr[0x0555] = 0xAAAAAAAA;
	addr[0x02AA] = 0x55555555;
	addr[0x0555] = 0x80808080;
	addr[0x0555] = 0xAAAAAAAA;
	addr[0x02AA] = 0x55555555;
	udelay (100);

	/* Start erase on unprotected sectors */
	for (sect = s_first; sect <= s_last; sect++) {
	if (info->protect[sect] == 0) { /* not protected */
	addr = (vu_long*)(info->start[sect]);
	addr[0] = 0x30303030;
	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 = (vu_long*)(info->start[l_sect]);
	while ((addr[0] & 0x80808080) != 0x80808080) {
	if ((now = get_timer(start)) > CONFIG_SYS_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 = (volatile unsigned long *)info->start[0];
	addr[0] = 0xF0F0F0F0; /* reset bank */

	printf (" done\n");
	return 0;
	}

	/*********************************************************************/
	/* NAME: write_buff() - writes a buffer to flash */
	/* */
	/* DESCRIPTION: */
	/* This function copies a buffer, src, to flash. /
	/* */
	/* INPUTS: */
	/* flash_info_t info - flash information structure /
	/* uchar src - pointer to buffer to write to flash /
	/* ulong addr - address to start write at */
	/* ulong cnt - number of bytes to write to flash */
	/* */
	/* OUTPUTS: */
	/* None */
	/* */
	/* RETURNS: */
	/* 0 - OK */
	/* 1 - write timeout */
	/* 2 - Flash not erased */
	/* */
	/* RESTRICTIONS/LIMITATIONS: */
	/* */
	/*********************************************************************/
	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));
	}

	/*********************************************************************/
	/* NAME: write_word() - writes a word to flash */
	/* */
	/* DESCRIPTION: */
	/* This writes a single word to flash. */
	/* */
	/* INPUTS: */
	/* flash_info_t info - flash information structure /
	/* ulong dest - address to write */
	/* ulong data - data to write */
	/* */
	/* OUTPUTS: */
	/* None */
	/* */
	/* RETURNS: */
	/* 0 - OK */
	/* 1 - write timeout */
	/* 2 - Flash not erased */
	/* */
	/* RESTRICTIONS/LIMITATIONS: */
	/* */
	/*********************************************************************/
	static int write_word (flash_info_t *info, ulong dest, ulong data)
	{
	vu_long addr = (vu_long)(info->start[0]);
	ulong start;
	int flag;

	/* 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();

	addr[0x0555] = 0xAAAAAAAA;
	addr[0x02AA] = 0x55555555;
	addr[0x0555] = 0xA0A0A0A0;

	((vu_long )dest) = data;

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

	/* data polling for D7 */
	start = get_timer (0);
	while ((((vu_long )dest) & 0x80808080) != (data & 0x80808080)) {
	if (get_timer(start) > CONFIG_SYS_FLASH_WRITE_TOUT) {
	return (1);
	}
	}
	return (0);
	}
	/*********************************************************************/
	/* End of flash.c */
	/*********************************************************************/