uboot-vybrid_public/board/amirix/ap1000/flash.c

/**
 * @file flash.c
 */

/*
 * (C) Copyright 2003
 * AMIRIX Systems Inc.
 *
 * Originated from ppcboot-2.0.0/board/esd/cpci440/strataflash.c
 *
 * (C) Copyright 2002
 * Brad Kemp, Seranoa Networks, Brad.Kemp@seranoa.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 <asm/processor.h>

#undef  DEBUG_FLASH
/*
 * This file implements a Common Flash Interface (CFI) driver for ppcboot.
 * The width of the port and the width of the chips are determined at initialization.
 * These widths are used to calculate the address for access CFI data structures.
 * It has been tested on an Intel Strataflash implementation.
 *
 * References
 * JEDEC Standard JESD68 - Common Flash Interface (CFI)
 * JEDEC Standard JEP137-A Common Flash Interface (CFI) ID Codes
 * Intel Application Note 646 Common Flash Interface (CFI) and Command Sets
 * Intel 290667-008 3 Volt Intel StrataFlash Memory datasheet
 *
 * TODO
 * Use Primary Extended Query table (PRI) and Alternate Algorithm Query Table (ALT) to determine if protection is available
 * Add support for other command sets Use the PRI and ALT to determine command set
 * Verify erase and program timeouts.
 */

#define FLASH_CMD_CFI           0x98
#define FLASH_CMD_READ_ID       0x90
#define FLASH_CMD_RESET         0xff
#define FLASH_CMD_BLOCK_ERASE       0x20
#define FLASH_CMD_ERASE_CONFIRM     0xD0
#define FLASH_CMD_WRITE         0x40
#define FLASH_CMD_PROTECT       0x60
#define FLASH_CMD_PROTECT_SET       0x01
#define FLASH_CMD_PROTECT_CLEAR     0xD0
#define FLASH_CMD_CLEAR_STATUS      0x50
#define FLASH_CMD_WRITE_TO_BUFFER       0xE8
#define FLASH_CMD_WRITE_BUFFER_CONFIRM  0xD0

#define FLASH_STATUS_DONE       0x80
#define FLASH_STATUS_ESS        0x40
#define FLASH_STATUS_ECLBS      0x20
#define FLASH_STATUS_PSLBS      0x10
#define FLASH_STATUS_VPENS      0x08
#define FLASH_STATUS_PSS        0x04
#define FLASH_STATUS_DPS        0x02
#define FLASH_STATUS_R          0x01
#define FLASH_STATUS_PROTECT        0x01

#define FLASH_OFFSET_CFI        0x55
#define FLASH_OFFSET_CFI_RESP       0x10
#define FLASH_OFFSET_WTOUT      0x1F
#define FLASH_OFFSET_WBTOUT             0x20
#define FLASH_OFFSET_ETOUT      0x21
#define FLASH_OFFSET_CETOUT             0x22
#define FLASH_OFFSET_WMAX_TOUT      0x23
#define FLASH_OFFSET_WBMAX_TOUT         0x24
#define FLASH_OFFSET_EMAX_TOUT      0x25
#define FLASH_OFFSET_CEMAX_TOUT         0x26
#define FLASH_OFFSET_SIZE       0x27
#define FLASH_OFFSET_INTERFACE          0x28
#define FLASH_OFFSET_BUFFER_SIZE        0x2A
#define FLASH_OFFSET_NUM_ERASE_REGIONS  0x2C
#define FLASH_OFFSET_ERASE_REGIONS  0x2D
#define FLASH_OFFSET_PROTECT        0x02
#define FLASH_OFFSET_USER_PROTECTION    0x85
#define FLASH_OFFSET_INTEL_PROTECTION   0x81


#define FLASH_MAN_CFI           0x01000000




typedef union {
    unsigned char c;
    unsigned short w;
    unsigned long l;
} cfiword_t;

typedef union {
    unsigned char * cp;
    unsigned short *wp;
    unsigned long *lp;
} cfiptr_t;

#define NUM_ERASE_REGIONS 4

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


/*-----------------------------------------------------------------------
 * Functions
 */



static void flash_add_byte(flash_info_t *info, cfiword_t * cword, uchar c);
static void flash_make_cmd(flash_info_t * info, uchar cmd, void * cmdbuf);
static void flash_write_cmd(flash_info_t * info, int sect, uchar offset, uchar cmd);
static int flash_isequal(flash_info_t * info, int sect, uchar offset, uchar cmd);
static int flash_isset(flash_info_t * info, int sect, uchar offset, uchar cmd);
static int flash_detect_cfi(flash_info_t * info);
static ulong flash_get_size (ulong base, int banknum);
static int flash_write_cfiword (flash_info_t *info, ulong dest, cfiword_t cword);
static int flash_full_status_check(flash_info_t * info, ulong sector, ulong tout, char * prompt);
#ifdef CFG_FLASH_USE_BUFFER_WRITE
static int flash_write_cfibuffer(flash_info_t * info, ulong dest, uchar * cp, int len);
#endif
/*-----------------------------------------------------------------------
 * create an address based on the offset and the port width
 */
uchar * flash_make_addr(flash_info_t * info, int sect, int offset)
{
    return ((uchar *)(info->start[sect] + (offset * info->chipwidth)));
}
/*-----------------------------------------------------------------------
 * read a character at a port width address
 */
uchar flash_read_uchar(flash_info_t * info, uchar offset)
{
    if (info->portwidth == FLASH_CFI_8BIT) {
        volatile uchar *cp;
        uchar c;
        cp = flash_make_addr(info, 0, offset);
        c = *cp;
#ifdef DEBUG_FLASH
        printf("flash_read_uchar offset=%04x ptr=%08x c=%02x\n",
                        offset, (unsigned int)cp, c);
#endif
        return (c);

    } else if (info->portwidth == FLASH_CFI_16BIT) {
        volatile ushort *sp;
        ushort s;
        uchar c;
        sp = (ushort*)flash_make_addr(info, 0, offset);
        s = *sp;
        c = (uchar)s;
#ifdef DEBUG_FLASH
        printf("flash_read_uchar offset=%04x ptr=%08x s=%04x c=%02x\n",
                       offset, (unsigned int)sp, s, c);
#endif
        return (c);

    }

    return 0;
}

/*-----------------------------------------------------------------------
 * read a short word by swapping for ppc format.
 */
ushort flash_read_ushort(flash_info_t * info, int sect,  uchar offset)
{
    if (info->portwidth == FLASH_CFI_8BIT) {
        volatile uchar *cp;
        uchar c0, c1;
        ushort s;
        cp = flash_make_addr(info, 0, offset);
        c1 = cp[2];
        c0 = cp[0];
        s = c1<<8 | c0;
#ifdef DEBUG_FLASH
        printf("flash_read_ushort offset=%04x ptr=%08x c1=%02x c0=%02x s=%04x\n",
                        offset, (unsigned int)cp, c1, c0, s);
#endif
        return (s);

    } else if (info->portwidth == FLASH_CFI_16BIT) {
        volatile ushort *sp;
        ushort s;
        uchar c0, c1;
        sp = (ushort*)flash_make_addr(info, 0, offset);
        s = *sp;
        c1 = (uchar)sp[1];
        c0 = (uchar)sp[0];
        s = c1<<8 | c0;
#ifdef DEBUG_FLASH
        printf("flash_read_ushort offset=%04x ptr=%08x c1=%02x c0=%02x s=%04x\n",
                        offset, (unsigned int)sp, c1, c0, s);
#endif
        return (s);

    }

    return 0;
}

/*-----------------------------------------------------------------------
 * read a long word by picking the least significant byte of each maiximum
 * port size word. Swap for ppc format.
 */
ulong flash_read_long(flash_info_t * info, int sect,  uchar offset)
{
    if (info->portwidth == FLASH_CFI_8BIT) {
        volatile uchar *cp;
        uchar c0, c1, c2, c3;
        ulong l;
        cp = flash_make_addr(info, 0, offset);
        c3 = cp[6];
        c2 = cp[4];
        c1 = cp[2];
        c0 = cp[0];
        l = c3<<24 | c2<<16 | c1<<8 | c0;
#ifdef DEBUG_FLASH
        printf("flash_read_long offset=%04x ptr=%08x c3=%02x c2=%02x c1=%02x c0=%02x l=%08x\n",
                        offset, (unsigned int)cp, c3, c2, c1, c0, l);
#endif
        return (l);

    } else if (info->portwidth == FLASH_CFI_16BIT) {
        volatile ushort *sp;
        uchar c0, c1, c2, c3;
        ulong l;
        sp = (ushort*)flash_make_addr(info, 0, offset);
        c3 = (uchar)sp[3];
        c2 = (uchar)sp[2];
        c1 = (uchar)sp[1];
        c0 = (uchar)sp[0];
        l = c3<<24 | c2<<16 | c1<<8 | c0;
#ifdef DEBUG_FLASH
        printf("flash_read_long offset=%04x ptr=%08x c3=%02x c2=%02x c1=%02x c0=%02x l=%08x\n",
                        offset, (unsigned int)sp, c3, c2, c1, c0, l);
#endif
        return (l);

    }

    return 0;
}

/*-----------------------------------------------------------------------
 */
unsigned long flash_init (void)
{
    unsigned long size;

    size = 0;

    flash_info[0].flash_id = FLASH_UNKNOWN;
    flash_info[0].portwidth = FLASH_CFI_16BIT;
    flash_info[0].chipwidth = FLASH_CFI_16BIT;
    size += flash_info[0].size = flash_get_size(CFG_PROGFLASH_BASE, 0);
    if (flash_info[0].flash_id == FLASH_UNKNOWN) {
        printf ("## Unknown FLASH on Bank %d - Size = 0x%08lx = %ld MB\n", 1,
        flash_info[0].size, flash_info[0].size<<20);
        };

    flash_info[1].flash_id = FLASH_UNKNOWN;
    flash_info[1].portwidth = FLASH_CFI_8BIT;
    flash_info[1].chipwidth = FLASH_CFI_16BIT;
    size += flash_info[1].size = flash_get_size(CFG_CONFFLASH_BASE, 1);
    if (flash_info[1].flash_id == FLASH_UNKNOWN) {
        printf ("## Unknown FLASH on Bank %d - Size = 0x%08lx = %ld MB\n", 2,
        flash_info[1].size, flash_info[1].size<<20);
    };

    return (size);
}

/*-----------------------------------------------------------------------
 */
int flash_erase (flash_info_t *info, int s_first, int s_last)
{
    int rcode = 0;
    int prot;
    int sect;

    if( info->flash_id != FLASH_MAN_CFI) {
        printf ("Can't erase unknown flash type - aborted\n");
        return 1;
    }
    if ((s_first < 0) || (s_first > s_last)) {
        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");
    }


    for (sect = s_first; sect<=s_last; sect++) {
        if (info->protect[sect] == 0) { /* not protected */
            flash_write_cmd(info, sect, 0, FLASH_CMD_CLEAR_STATUS);
            flash_write_cmd(info, sect, 0, FLASH_CMD_BLOCK_ERASE);
            flash_write_cmd(info, sect, 0, FLASH_CMD_ERASE_CONFIRM);

            if(flash_full_status_check(info, sect, info->erase_blk_tout, "erase")) {
                rcode = 1;
            } else
                printf(".");
        }
    }
    printf (" done\n");
    return rcode;
}

/*-----------------------------------------------------------------------
 */
void flash_print_info  (flash_info_t *info)
{
    int i;

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

    printf("CFI conformant FLASH (x%d device in x%d mode)",
           (info->chipwidth  << 3 ), (info->portwidth  << 3 ));
    printf ("  Size: %ld MB in %d Sectors\n",
        info->size >> 20, info->sector_count);
    printf(" Erase timeout %ld ms, write timeout %ld ms, buffer write timeout %ld ms, buffer size %d\n",
           info->erase_blk_tout, info->write_tout, info->buffer_write_tout, info->buffer_size);

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

/*-----------------------------------------------------------------------
 * 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 wp;
    ulong cp;
    int aln;
    cfiword_t cword;
    int i, rc;

    /* get lower aligned address */
    wp = (addr & ~(info->portwidth - 1));

    /* handle unaligned start */
    if((aln = addr - wp) != 0) {
        cword.l = 0;
        cp = wp;
        for(i=0;i<aln; ++i, ++cp)
            flash_add_byte(info, &cword, (*(uchar *)cp));

        for(; (i< info->portwidth) && (cnt > 0) ; i++) {
            flash_add_byte(info, &cword, *src++);
            cnt--;
            cp++;
        }
        for(; (cnt == 0) && (i < info->portwidth); ++i, ++cp)
            flash_add_byte(info, &cword, (*(uchar *)cp));
        if((rc = flash_write_cfiword(info, wp, cword)) != 0)
            return rc;
        wp = cp;
    }

#ifdef CFG_FLASH_USE_BUFFER_WRITE
    while(cnt >= info->portwidth) {
        i = info->buffer_size > cnt? cnt: info->buffer_size;
        if((rc = flash_write_cfibuffer(info, wp, src,i)) != ERR_OK)
            return rc;
        wp += i;
        src += i;
        cnt -=i;
    }
#else
    /* handle the aligned part */
    while(cnt >= info->portwidth) {
        cword.l = 0;
        for(i = 0; i < info->portwidth; i++) {
            flash_add_byte(info, &cword, *src++);
        }
        if((rc = flash_write_cfiword(info, wp, cword)) != 0)
            return rc;
        wp += info->portwidth;
        cnt -= info->portwidth;
    }
#endif /* CFG_FLASH_USE_BUFFER_WRITE */
    if (cnt == 0) {
        return (0);
    }

    /*
     * handle unaligned tail bytes
     */
    cword.l = 0;
    for (i=0, cp=wp; (i<info->portwidth) && (cnt>0); ++i, ++cp) {
        flash_add_byte(info, &cword, *src++);
        --cnt;
    }
    for (; i<info->portwidth; ++i, ++cp) {
        flash_add_byte(info, & cword, (*(uchar *)cp));
    }

    return flash_write_cfiword(info, wp, cword);
}

/*-----------------------------------------------------------------------
 */
int flash_real_protect(flash_info_t *info, long sector, int prot)
{
    int retcode = 0;

    flash_write_cmd(info, sector, 0, FLASH_CMD_CLEAR_STATUS);
    flash_write_cmd(info, sector, 0, FLASH_CMD_PROTECT);
    if(prot)
        flash_write_cmd(info, sector, 0, FLASH_CMD_PROTECT_SET);
    else
        flash_write_cmd(info, sector, 0, FLASH_CMD_PROTECT_CLEAR);

    if((retcode = flash_full_status_check(info, sector, info->erase_blk_tout,
                     prot?"protect":"unprotect")) == 0) {

        info->protect[sector] = prot;
        /* Intel's unprotect unprotects all locking */
        if(prot == 0) {
            int i;
            for(i = 0 ; i<info->sector_count; i++) {
                if(info->protect[i])
                    flash_real_protect(info, i, 1);
            }
        }
    }

    return retcode;
}
/*-----------------------------------------------------------------------
 *  wait for XSR.7 to be set. Time out with an error if it does not.
 *  This routine does not set the flash to read-array mode.
 */
static int flash_status_check(flash_info_t * info, ulong sector, ulong tout, char * prompt)
{
    ulong start;

    /* Wait for command completion */
    start = get_timer (0);
    while(!flash_isset(info, sector, 0, FLASH_STATUS_DONE)) {
        if (get_timer(start) > info->erase_blk_tout) {
            printf("Flash %s timeout at address %lx\n", prompt, info->start[sector]);
            flash_write_cmd(info, sector, 0, FLASH_CMD_RESET);
            return ERR_TIMOUT;
        }
    }
    return ERR_OK;
}
/*-----------------------------------------------------------------------
 * Wait for XSR.7 to be set, if it times out print an error, otherwise do a full status check.
 * This routine sets the flash to read-array mode.
 */
static int flash_full_status_check(flash_info_t * info, ulong sector, ulong tout, char * prompt)
{
    int retcode;
    retcode = flash_status_check(info, sector, tout, prompt);
    if((retcode == ERR_OK) && !flash_isequal(info,sector, 0, FLASH_STATUS_DONE)) {
        retcode = ERR_INVAL;
        printf("Flash %s error at address %lx\n", prompt,info->start[sector]);
        if(flash_isset(info, sector, 0, FLASH_STATUS_ECLBS | FLASH_STATUS_PSLBS)){
            printf("Command Sequence Error.\n");
        } else if(flash_isset(info, sector, 0, FLASH_STATUS_ECLBS)){
            printf("Block Erase Error.\n");
                retcode = ERR_NOT_ERASED;
        } else if (flash_isset(info, sector, 0, FLASH_STATUS_PSLBS)) {
            printf("Locking Error\n");
        }
        if(flash_isset(info, sector, 0, FLASH_STATUS_DPS)){
            printf("Block locked.\n");
            retcode = ERR_PROTECTED;
        }
        if(flash_isset(info, sector, 0, FLASH_STATUS_VPENS))
            printf("Vpp Low Error.\n");
    }
    flash_write_cmd(info, sector, 0, FLASH_CMD_RESET);
    return retcode;
}
/*-----------------------------------------------------------------------
 */
static void flash_add_byte(flash_info_t *info, cfiword_t * cword, uchar c)
{
    switch(info->portwidth) {
    case FLASH_CFI_8BIT:
        cword->c = c;
        break;
    case FLASH_CFI_16BIT:
        cword->w = (cword->w << 8) | c;
        break;
    case FLASH_CFI_32BIT:
        cword->l = (cword->l << 8) | c;
    }
}


/*-----------------------------------------------------------------------
 * make a proper sized command based on the port and chip widths
 */
static void flash_make_cmd(flash_info_t * info, uchar cmd, void * cmdbuf)
{
    //int i;
    uchar *cp = (uchar *)cmdbuf;
    // for(i=0; i< info->portwidth; i++)
    //  *cp++ = ((i+1) % info->chipwidth) ? '\0':cmd;
        if (info->portwidth == FLASH_CFI_8BIT && info->chipwidth == FLASH_CFI_16BIT) {
        cp[0] = cmd;
        } else if (info->portwidth == FLASH_CFI_16BIT && info->chipwidth == FLASH_CFI_16BIT) {
        cp[0] = '\0';
        cp[1] = cmd;
    };
}

/*
 * Write a proper sized command to the correct address
 */
static void flash_write_cmd(flash_info_t * info, int sect, uchar offset, uchar cmd)
{

    volatile cfiptr_t addr;
    cfiword_t cword;
    addr.cp = flash_make_addr(info, sect, offset);
    flash_make_cmd(info, cmd, &cword);
    switch(info->portwidth) {
    case FLASH_CFI_8BIT:
        *addr.cp = cword.c;
        break;
    case FLASH_CFI_16BIT:
        *addr.wp = cword.w;
        break;
    case FLASH_CFI_32BIT:
        *addr.lp = cword.l;
        break;
    }
}

/*-----------------------------------------------------------------------
 */
static int flash_isequal(flash_info_t * info, int sect, uchar offset, uchar cmd)
{
    cfiptr_t cptr;
    cfiword_t cword;
    int retval;
    cptr.cp = flash_make_addr(info, sect, offset);
    flash_make_cmd(info, cmd, &cword);
    switch(info->portwidth) {
    case FLASH_CFI_8BIT:
        retval = (cptr.cp[0] == cword.c);
        break;
    case FLASH_CFI_16BIT:
        retval = (cptr.wp[0] == cword.w);
        break;
    case FLASH_CFI_32BIT:
        retval = (cptr.lp[0] == cword.l);
        break;
    default:
        retval = 0;
        break;
    }
    return retval;
}
/*-----------------------------------------------------------------------
 */
static int flash_isset(flash_info_t * info, int sect, uchar offset, uchar cmd)
{
    cfiptr_t cptr;
    cfiword_t cword;
    int retval;
    cptr.cp = flash_make_addr(info, sect, offset);
    flash_make_cmd(info, cmd, &cword);
    switch(info->portwidth) {
    case FLASH_CFI_8BIT:
        retval = ((cptr.cp[0] & cword.c) == cword.c);
        break;
    case FLASH_CFI_16BIT:
        retval = ((cptr.wp[0] & cword.w) == cword.w);
        break;
    case FLASH_CFI_32BIT:
        retval = ((cptr.lp[0] & cword.l) == cword.l);
        break;
    default:
        retval = 0;
        break;
    }
    return retval;
}

/*-----------------------------------------------------------------------
 * detect if flash is compatible with the Common Flash Interface (CFI)
 * http://www.jedec.org/download/search/jesd68.pdf
 *
*/
static int flash_detect_cfi(flash_info_t * info)
{

#if 0
    for(info->portwidth=FLASH_CFI_8BIT; info->portwidth <= FLASH_CFI_32BIT;
        info->portwidth <<= 1) {
        for(info->chipwidth =FLASH_CFI_BY8;
            info->chipwidth <= info->portwidth;
            info->chipwidth <<= 1) {
            flash_write_cmd(info, 0, 0, FLASH_CMD_RESET);
            flash_write_cmd(info, 0, FLASH_OFFSET_CFI, FLASH_CMD_CFI);
            if(flash_isequal(info, 0, FLASH_OFFSET_CFI_RESP,'Q') &&
               flash_isequal(info, 0, FLASH_OFFSET_CFI_RESP + 1, 'R') &&
               flash_isequal(info, 0, FLASH_OFFSET_CFI_RESP + 2, 'Y'))
                return 1;
        }
    }
#endif
    flash_write_cmd(info, 0, 0, FLASH_CMD_RESET);
    flash_write_cmd(info, 0, FLASH_OFFSET_CFI, FLASH_CMD_CFI);
    if(flash_isequal(info, 0, FLASH_OFFSET_CFI_RESP,'Q') &&
       flash_isequal(info, 0, FLASH_OFFSET_CFI_RESP + 1, 'R') &&
       flash_isequal(info, 0, FLASH_OFFSET_CFI_RESP + 2, 'Y')) {
        return 1;
    } else {
        return 0;
    };
}
/*
 * The following code cannot be run from FLASH!
 *
 */
static ulong flash_get_size (ulong base, int banknum)
{
    flash_info_t * info = &flash_info[banknum];
    int i, j;
    int sect_cnt;
    unsigned long sector;
    unsigned long tmp;
    int size_ratio;
    uchar num_erase_regions;
    int  erase_region_size;
    int  erase_region_count;

    info->start[0] = base;

    if(flash_detect_cfi(info)){
#ifdef DEBUG_FLASH
        printf("portwidth=%d chipwidth=%d\n", info->portwidth, info->chipwidth); /* test-only */
#endif
        size_ratio = 1; // info->portwidth / info->chipwidth;
        num_erase_regions = flash_read_uchar(info, FLASH_OFFSET_NUM_ERASE_REGIONS);
#ifdef DEBUG_FLASH
        printf("found %d erase regions\n", num_erase_regions);
#endif
        sect_cnt = 0;
        sector = base;
        for(i = 0 ; i < num_erase_regions; i++) {
            if(i > NUM_ERASE_REGIONS) {
                printf("%d erase regions found, only %d used\n",
                       num_erase_regions, NUM_ERASE_REGIONS);
                break;
            }
            tmp = flash_read_long(info, 0, FLASH_OFFSET_ERASE_REGIONS);
            erase_region_count = (tmp & 0xffff) +1;
            tmp >>= 16;
            erase_region_size = (tmp & 0xffff)? ((tmp & 0xffff) * 256): 128;
            for(j = 0; j< erase_region_count; j++) {
                info->start[sect_cnt] = sector;
                sector += (erase_region_size * size_ratio);
                info->protect[sect_cnt] = flash_isset(info, sect_cnt, FLASH_OFFSET_PROTECT, FLASH_STATUS_PROTECT);
                sect_cnt++;
            }
        }

        info->sector_count = sect_cnt;
        /* multiply the size by the number of chips */
        info->size = (1 << flash_read_uchar(info, FLASH_OFFSET_SIZE)) * size_ratio;
        info->buffer_size = (1 << flash_read_ushort(info, 0, FLASH_OFFSET_BUFFER_SIZE));
        tmp = 1 << flash_read_uchar(info, FLASH_OFFSET_ETOUT);
        info->erase_blk_tout = (tmp * (1 << flash_read_uchar(info, FLASH_OFFSET_EMAX_TOUT)));
        tmp = 1 << flash_read_uchar(info, FLASH_OFFSET_WBTOUT);
        info->buffer_write_tout = (tmp * (1 << flash_read_uchar(info, FLASH_OFFSET_WBMAX_TOUT)));
        tmp = 1 << flash_read_uchar(info, FLASH_OFFSET_WTOUT);
        info->write_tout = (tmp * (1 << flash_read_uchar(info, FLASH_OFFSET_WMAX_TOUT)))/ 1000;
        info->flash_id = FLASH_MAN_CFI;
    }

    flash_write_cmd(info, 0, 0, FLASH_CMD_RESET);
    return(info->size);
}


/*-----------------------------------------------------------------------
 */
static int flash_write_cfiword (flash_info_t *info, ulong dest, cfiword_t cword)
{

    cfiptr_t ctladdr;
    cfiptr_t cptr;
    int flag;

    ctladdr.cp = flash_make_addr(info, 0, 0);
    cptr.cp = (uchar *)dest;


    /* Check if Flash is (sufficiently) erased */
    switch(info->portwidth) {
    case FLASH_CFI_8BIT:
        flag = ((cptr.cp[0] & cword.c) == cword.c);
        break;
    case FLASH_CFI_16BIT:
        flag = ((cptr.wp[0] & cword.w) == cword.w);
        break;
    case FLASH_CFI_32BIT:
        flag = ((cptr.lp[0] & cword.l)  == cword.l);
        break;
    default:
        return 2;
    }
    if(!flag)
        return 2;

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

    flash_write_cmd(info, 0, 0, FLASH_CMD_CLEAR_STATUS);
    flash_write_cmd(info, 0, 0, FLASH_CMD_WRITE);

    switch(info->portwidth) {
    case FLASH_CFI_8BIT:
        cptr.cp[0] = cword.c;
        break;
    case FLASH_CFI_16BIT:
        cptr.wp[0] = cword.w;
        break;
    case FLASH_CFI_32BIT:
        cptr.lp[0] = cword.l;
        break;
    }

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

    return flash_full_status_check(info, 0, info->write_tout, "write");
}

#ifdef CFG_FLASH_USE_BUFFER_WRITE

/* loop through the sectors from the highest address
 * when the passed address is greater or equal to the sector address
 * we have a match
 */
static int find_sector(flash_info_t *info, ulong addr)
{
    int sector;
    for(sector = info->sector_count - 1; sector >= 0; sector--) {
        if(addr >= info->start[sector])
            break;
    }
    return sector;
}

static int flash_write_cfibuffer(flash_info_t * info, ulong dest, uchar * cp, int len)
{

    int sector;
    int cnt;
    int retcode;
    volatile cfiptr_t src;
    volatile cfiptr_t dst;

    src.cp = cp;
    dst.cp = (uchar *)dest;
    sector = find_sector(info, dest);
    flash_write_cmd(info, sector, 0, FLASH_CMD_CLEAR_STATUS);
    flash_write_cmd(info, sector, 0, FLASH_CMD_WRITE_TO_BUFFER);
    if((retcode = flash_status_check(info, sector, info->buffer_write_tout,
                     "write to buffer")) == ERR_OK) {
        switch(info->portwidth) {
        case FLASH_CFI_8BIT:
            cnt = len;
            break;
        case FLASH_CFI_16BIT:
            cnt = len >> 1;
            break;
        case FLASH_CFI_32BIT:
            cnt = len >> 2;
            break;
        default:
            return ERR_INVAL;
            break;
        }
        flash_write_cmd(info, sector, 0, (uchar)cnt-1);
        while(cnt-- > 0) {
            switch(info->portwidth) {
            case FLASH_CFI_8BIT:
                *dst.cp++ = *src.cp++;
                break;
            case FLASH_CFI_16BIT:
                *dst.wp++ = *src.wp++;
                break;
            case FLASH_CFI_32BIT:
                *dst.lp++ = *src.lp++;
                break;
            default:
                return ERR_INVAL;
                break;
            }
        }
        flash_write_cmd(info, sector, 0, FLASH_CMD_WRITE_BUFFER_CONFIRM);
        retcode = flash_full_status_check(info, sector, info->buffer_write_tout,
                         "buffer write");
    }
    flash_write_cmd(info, sector, 0, FLASH_CMD_CLEAR_STATUS);
    return retcode;
}
#endif /* CFG_USE_FLASH_BUFFER_WRITE */