/*
 * (C) Copyright 2001
 * Erik Theisen, Wave 7 Optics, etheisen@mindspring.com.
 *  Based on code by:
 * Wolfgang Denk, DENX Software Engineering, wd@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 <common.h>
#include <asm/ppc4xx.h>
#include <asm/processor.h>

#include <watchdog.h>

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

/*
 * Functions
 */
static ulong flash_get_size(vu_long *addr, flash_info_t *info);
static int write_word8(flash_info_t *info, ulong dest, ulong data);
static int write_word32(flash_info_t *info, ulong dest, ulong data);
static void flash_get_offsets(ulong base, flash_info_t *info);

unsigned long flash_init(void)
{
        int i;
        unsigned long size_b0, base_b0;
        unsigned long size_b1;

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

        /* Get Size of Boot and Main Flashes */
        size_b0 = flash_get_size((vu_long *) FLASH_BASE0_PRELIM,
                               &flash_info[0]);
        if (flash_info[0].flash_id == FLASH_UNKNOWN) {
                printf("## Unknown FLASH on Bank 0 - Size = 0x%08lx = %ld MB\n",
                        size_b0, size_b0 << 20);
                return 0;
        }
        size_b1 =
                flash_get_size((vu_long *) FLASH_BASE1_PRELIM,
                               &flash_info[1]);
        if (flash_info[1].flash_id == FLASH_UNKNOWN) {
                printf("## Unknown FLASH on Bank 1 - Size = 0x%08lx = %ld MB\n",
                        size_b1, size_b1 << 20);
                return 0;
        }

        /* Calculate base addresses */
        base_b0 = -size_b0;

        /* Setup offsets for Boot Flash */
        flash_get_offsets(base_b0, &flash_info[0]);

        /* Protect board level data */
        (void) flash_protect(FLAG_PROTECT_SET,
                             base_b0,
                             flash_info[0].start[1] - 1, &flash_info[0]);

        /* Monitor protection ON by default */
        (void) flash_protect(FLAG_PROTECT_SET,
                             base_b0 + size_b0 - monitor_flash_len,
                             base_b0 + size_b0 - 1, &flash_info[0]);

        /* Protect the FPGA image */
        (void) flash_protect(FLAG_PROTECT_SET,
                             FLASH_BASE1_PRELIM,
                             FLASH_BASE1_PRELIM + CONFIG_SYS_FPGA_IMAGE_LEN -
                             1, &flash_info[1]);

        /* Protect the default boot image */
        (void) flash_protect(FLAG_PROTECT_SET,
                             FLASH_BASE1_PRELIM + CONFIG_SYS_FPGA_IMAGE_LEN,
                             FLASH_BASE1_PRELIM + CONFIG_SYS_FPGA_IMAGE_LEN +
                             0x600000 - 1, &flash_info[1]);

        /* Setup offsets for Main Flash */
        flash_get_offsets(FLASH_BASE1_PRELIM, &flash_info[1]);

        return size_b0 + size_b1;
}

static void flash_get_offsets(ulong base, flash_info_t *info)
{
        int i;

        /* set up sector start address table - FOR BOOT ROM ONLY!!! */
        if ((info->flash_id & FLASH_TYPEMASK) == FLASH_AM040) {
                for (i = 0; i < info->sector_count; i++)
                        info->start[i] = base + (i * 0x00010000);
        }
}                               /* end flash_get_offsets() */

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("1 x AMD ");
                break;
        case FLASH_MAN_STM:
                printf("1 x STM ");
                break;
        case FLASH_MAN_INTEL:
                printf("2 x Intel ");
                break;
        default:
                printf("Unknown Vendor ");
        }

        switch (info->flash_id & FLASH_TYPEMASK) {
        case FLASH_AM040:
                if ((info->flash_id & FLASH_VENDMASK) == FLASH_MAN_AMD)
                        printf("AM29LV040 (4096 Kbit, uniform sector size)\n");
                else if ((info->flash_id & FLASH_VENDMASK) == FLASH_MAN_STM)
                        printf("M29W040B (4096 Kbit, uniform block size)\n");
                else
                        printf("UNKNOWN 29x040x (4096 Kbit, uniform sector size)\n");
                break;
        case FLASH_28F320J3A:
                printf("28F320J3A (32 Mbit = 128K x 32)\n");
                break;
        case FLASH_28F640J3A:
                printf("28F640J3A (64 Mbit = 128K x 64)\n");
                break;
        case FLASH_28F128J3A:
                printf("28F128J3A (128 Mbit = 128K x 128)\n");
                break;
        default:
                printf("Unknown Chip Type\n");
        }

        if ((info->flash_id & FLASH_VENDMASK) == FLASH_MAN_STM) {
                printf("  Size: %ld KB in %d Blocks\n",
                       info->size >> 10, info->sector_count);
        } else {
                printf("  Size: %ld KB in %d Sectors\n",
                       info->size >> 10, info->sector_count);
        }

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

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

        /* Setup default type */
        info->flash_id = FLASH_UNKNOWN;
        info->sector_count = 0;
        info->size = 0;

        /* Test for Boot Flash */
        if (base == FLASH_BASE0_PRELIM) {
                unsigned char value;
                volatile unsigned char *addr2 = (unsigned char *) addr;

                /* Write auto select command: read Manufacturer ID */
                *(addr2 + 0x555) = 0xaa;
                *(addr2 + 0x2aa) = 0x55;
                *(addr2 + 0x555) = 0x90;

                /* Manufacture ID */
                value = *addr2;
                switch (value) {
                case (unsigned char) AMD_MANUFACT:
                        info->flash_id = FLASH_MAN_AMD;
                        break;
                case (unsigned char) STM_MANUFACT:
                        info->flash_id = FLASH_MAN_STM;
                        break;
                default:
                        *addr2 = 0xf0;  /* no or unknown flash  */
                        return 0;
                }

                /* Device ID */
                value = *(addr2 + 1);
                switch (value) {
                case (unsigned char) AMD_ID_LV040B:
                case (unsigned char) STM_ID_29W040B:
                        info->flash_id += FLASH_AM040;
                        info->sector_count = 8;
                        info->size = 0x00080000;
                        break;  /* => 512Kb */
                default:
                        *addr2 = 0xf0;  /* => no or unknown flash */
                        return 0;
                }
        } else {                /* MAIN Flash */
                unsigned long value;
                volatile unsigned long *addr2 = (unsigned long *) addr;

                /* Write auto select command: read Manufacturer ID */
                *addr2 = 0x90909090;

                /* Manufacture ID */
                value = *addr2;
                switch (value) {
                case (unsigned long) INTEL_MANUFACT:
                        info->flash_id = FLASH_MAN_INTEL;
                        break;
                default:
                        *addr2 = 0xff;  /* no or unknown flash  */
                        return 0;
                }

                /* Device ID - This shit is interleaved... */
                value = *(addr2 + 1);
                switch (value) {
                case (unsigned long) INTEL_ID_28F320J3A:
                        info->flash_id += FLASH_28F320J3A;
                        info->sector_count = 32;
                        info->size = 0x00400000 * 2;
                        break;  /* => 2 X 4 MB */
                case (unsigned long) INTEL_ID_28F640J3A:
                        info->flash_id += FLASH_28F640J3A;
                        info->sector_count = 64;
                        info->size = 0x00800000 * 2;
                        break;  /* => 2 X 8 MB */
                case (unsigned long) INTEL_ID_28F128J3A:
                        info->flash_id += FLASH_28F128J3A;
                        info->sector_count = 128;
                        info->size = 0x01000000 * 2;
                        break;  /* => 2 X 16 MB */
                default:
                        *addr2 = 0xff;  /* => no or unknown flash */
                }
        }

        /* Make sure we don't exceed CONFIG_SYS_MAX_FLASH_SECT */
        if (info->sector_count > CONFIG_SYS_MAX_FLASH_SECT) {
                printf("** ERROR: sector count %d > max (%d) **\n",
                       info->sector_count, CONFIG_SYS_MAX_FLASH_SECT);
                info->sector_count = CONFIG_SYS_MAX_FLASH_SECT;
        }

        /* set up sector start address table */
        switch (info->flash_id & FLASH_TYPEMASK) {
        case FLASH_AM040:
                for (i = 0; i < info->sector_count; i++)
                        info->start[i] = base + (i * 0x00010000);
                break;
        case FLASH_28F320J3A:
        case FLASH_28F640J3A:
        case FLASH_28F128J3A:
                for (i = 0; i < info->sector_count; i++)
                        info->start[i] = base +
                                        (i * 0x00020000 * 2);   /* 2 Banks */
                break;
        }

        /* Test for Boot Flash */
        if (base == FLASH_BASE0_PRELIM) {
                volatile unsigned char *addr2;

                /* check for protected sectors */
                for (i = 0; i < info->sector_count; i++) {
                        /*
                         * read sector protection at sector address,
                         * (AX .. A0) = 0x02
                         * D0 = 1 if protected
                         */
                        addr2 = (volatile unsigned char *) (info->start[i]);
                        info->protect[i] = *(addr2 + 2) & 1;
                }

                /* Restore read mode */
                *(unsigned char *) base = 0xF0; /* Reset NORMAL Flash */
        } else {                /* Main Flash */
                volatile unsigned long *addr2;

                /* check for protected sectors */
                for (i = 0; i < info->sector_count; i++) {
                        /*
                         * read sector protection at sector address,
                         * (AX .. A0) = 0x02
                         * D0 = 1 if protected
                         */
                        addr2 = (volatile unsigned long *) (info->start[i]);
                        info->protect[i] = *(addr2 + 2) & 0x1;
                }

                /* Restore read mode */
                *(unsigned long *) base = 0xFFFFFFFF;   /* Reset  Flash */
        }

        return info->size;
}                               /* end flash_get_size() */

static int wait_for_DQ7(ulong addr, uchar cmp_val, ulong tout)
{
        int i;

        volatile uchar *vaddr = (uchar *) addr;

        /* Loop X times */
        for (i = 1; i <= (100 * tout); i++) {   /* Wait up to tout ms */
                udelay(10);
                /* Pause 10 us */

                /* Check for completion */
                if ((vaddr[0] & 0x80) == (cmp_val & 0x80))
                        return 0;

                /* KEEP THE LUSER HAPPY - Print a dot every 1.1 seconds */
                if (!(i % 110000))
                        putc('.');

                /* Kick the dog if needed */
                WATCHDOG_RESET();
        }

        return 1;
}                               /* wait_for_DQ7() */

static int flash_erase8(flash_info_t *info, int s_first, int s_last)
{
        int tcode, rcode = 0;
        volatile uchar *addr = (uchar *) (info->start[0]);
        volatile uchar *sector_addr;
        int flag, prot, sect;

        /* Validate arguments */
        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;
        }

        /* Check for KNOWN flash type */
        if (info->flash_id == FLASH_UNKNOWN) {
                printf("Can't erase unknown flash type - aborted\n");
                return 1;
        }

        /* Check for protected sectors */
        prot = 0;
        for (sect = s_first; sect <= s_last; ++sect) {
                if (info->protect[sect])
                        prot++;
        }
        if (prot) {
                printf("- Warning: %d protected sectors will not be erased!\n",
                        prot);
        } else {
                printf("\n");
        }

        /* Start erase on unprotected sectors */
        for (sect = s_first; sect <= s_last; sect++) {
                if (info->protect[sect] == 0) { /* not protected */
                        sector_addr = (uchar *) (info->start[sect]);

                        if ((info->flash_id & FLASH_VENDMASK) ==
                            FLASH_MAN_STM)
                                printf("Erasing block %p\n", sector_addr);
                        else
                                printf("Erasing sector %p\n", sector_addr);

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

                        *(addr + 0x555) = (uchar) 0xAA;
                        *(addr + 0x2aa) = (uchar) 0x55;
                        *(addr + 0x555) = (uchar) 0x80;
                        *(addr + 0x555) = (uchar) 0xAA;
                        *(addr + 0x2aa) = (uchar) 0x55;
                        *sector_addr = (uchar) 0x30;    /* sector erase */

                        /*
                         * Wait for each sector to complete, it's more
                         * reliable.  According to AMD Spec, you must
                         * issue all erase commands within a specified
                         * timeout.  This has been seen to fail, especially
                         * if printf()s are included (for debug)!!
                         * Takes up to 6 seconds.
                         */
                        tcode = wait_for_DQ7((ulong) sector_addr, 0x80, 6000);

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

                        /* Make sure we didn't timeout */
                        if (tcode) {
                                printf("Timeout\n");
                                rcode = 1;
                        }
                }
        }

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

        /* reset to read mode */
        addr = (uchar *) info->start[0];
        *addr = (uchar) 0xF0;   /* reset bank */

        printf(" done\n");
        return rcode;
}                               /* end flash_erase8() */

static int flash_erase32(flash_info_t *info, int s_first, int s_last)
{
        int flag, sect;
        ulong start, now, last;
        int prot = 0;

        /* Validate arguments */
        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;
        }

        /* Check for KNOWN flash type */
        if ((info->flash_id & FLASH_VENDMASK) != FLASH_MAN_INTEL) {
                printf("Can erase only Intel flash types - aborted\n");
                return 1;
        }

        /* Check for protected sectors */
        for (sect = s_first; sect <= s_last; ++sect) {
                if (info->protect[sect])
                        prot++;
        }
        if (prot) {
                printf("- Warning: %d protected sectors will not be erased!\n",
                        prot);
        } else {
                printf("\n");
        }

        start = get_timer(0);
        last = start;
        /* Start erase on unprotected sectors */
        for (sect = s_first; sect <= s_last; sect++) {
                WATCHDOG_RESET();
                if (info->protect[sect] == 0) { /* not protected */
                        vu_long *addr = (vu_long *) (info->start[sect]);
                        unsigned long status;

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

                        *addr = 0x00500050;     /* clear status register */
                        *addr = 0x00200020;     /* erase setup */
                        *addr = 0x00D000D0;     /* erase confirm */

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

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

                        while (((status = *addr) & 0x00800080) != 0x00800080) {
                                now = get_timer(start);
                                if (now > CONFIG_SYS_FLASH_ERASE_TOUT) {
                                        printf("Timeout\n");
                                        /* suspend erase      */
                                        *addr = 0x00B000B0;
                                        /* reset to read mode */
                                        *addr = 0x00FF00FF;
                                        return 1;
                                }

                                /*
                                 * show that we're waiting
                                 * every second (?)
                                 */
                                if ((now - last) > 990) {
                                        putc('.');
                                        last = now;
                                }
                        }
                        *addr = 0x00FF00FF;     /* reset to read mode */
                }
        }
        printf(" done\n");
        return 0;
}

int flash_erase(flash_info_t *info, int s_first, int s_last)
{
        if ((info->flash_id & FLASH_TYPEMASK) == FLASH_AM040)
                return flash_erase8(info, s_first, s_last);
        else
                return flash_erase32(info, s_first, s_last);
}

/*
 * Copy memory to flash, returns:
 * 0 - OK
 * 1 - write timeout
 * 2 - Flash not erased
 */
static int write_buff8(flash_info_t *info, uchar *src, ulong addr,
                       ulong cnt)
{
        ulong cp, wp, data;
        ulong start;
        int i, l, rc;

        start = get_timer(0);

        wp = (addr & ~3);       /* get lower word
                                   aligned address */

        /*
         * handle unaligned start bytes
         */
        l = addr - wp;
        if (l != 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);

                rc = write_word8(info, wp, data);
                if (rc != 0)
                        return rc;

                wp += 4;
        }

        /*
         * handle word aligned part
         */
        while (cnt >= 4) {
                data = 0;
                for (i = 0; i < 4; ++i)
                        data = (data << 8) | *src++;

                rc = write_word8(info, wp, data);
                if (rc != 0)
                        return rc;

                wp += 4;
                cnt -= 4;
                if (get_timer(start) > 1000) {  /* every second */
                        WATCHDOG_RESET();
                        putc('.');
                        start = get_timer(0);
                }
        }

        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_word8(info, wp, data);
}

#define FLASH_WIDTH     4       /* flash bus width in bytes */
static int write_buff32(flash_info_t *info, uchar *src, ulong addr,
                        ulong cnt)
{
        ulong cp, wp, data;
        int i, l, rc;
        ulong start;

        start = get_timer(0);

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

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

        /*
         * handle unaligned start bytes
         */
        if ((l = addr - wp) != 0) {
                data = 0;
                for (i = 0, cp = wp; i < l; ++i, ++cp)
                        data = (data << 8) | (*(uchar *) cp);

                for (; i < FLASH_WIDTH && cnt > 0; ++i) {
                        data = (data << 8) | *src++;
                        --cnt;
                        ++cp;
                }

                for (; cnt == 0 && i < FLASH_WIDTH; ++i, ++cp)
                        data = (data << 8) | (*(uchar *) cp);

                rc = write_word32(info, wp, data);
                if (rc != 0)
                        return rc;

                wp += FLASH_WIDTH;
        }

        /*
         * handle FLASH_WIDTH aligned part
         */
        while (cnt >= FLASH_WIDTH) {
                data = 0;
                for (i = 0; i < FLASH_WIDTH; ++i)
                        data = (data << 8) | *src++;

                rc = write_word32(info, wp, data);
                if (rc != 0)
                        return rc;

                wp += FLASH_WIDTH;
                cnt -= FLASH_WIDTH;
                if (get_timer(start) > 990) {   /* every second */
                        putc('.');
                        start = get_timer(0);
                }
        }

        if (cnt == 0)
                return 0;

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

        for (; i < FLASH_WIDTH; ++i, ++cp)
                data = (data << 8) | (*(uchar *) cp);

        return write_word32(info, wp, data);
}

int write_buff(flash_info_t *info, uchar *src, ulong addr, ulong cnt)
{
        int retval;

        if ((info->flash_id & FLASH_TYPEMASK) == FLASH_AM040)
                retval = write_buff8(info, src, addr, cnt);
        else
                retval = write_buff32(info, src, addr, cnt);

        return retval;
}

/*
 * Write a word to Flash, returns:
 * 0 - OK
 * 1 - write timeout
 * 2 - Flash not erased
 */

static int write_word8(flash_info_t *info, ulong dest, ulong data)
{
        volatile uchar *addr2 = (uchar *) (info->start[0]);
        volatile uchar *dest2 = (uchar *) dest;
        volatile uchar *data2 = (uchar *) &data;
        int flag;
        int i, tcode, rcode = 0;

        /* Check if Flash is (sufficently) erased */
        if ((*((volatile uchar *)dest) & (uchar)data) != (uchar)data)
                return 2;

        for (i = 0; i < (4 / sizeof(uchar)); i++) {
                /* Disable interrupts which might cause a timeout here */
                flag = disable_interrupts();

                *(addr2 + 0x555) = (uchar) 0xAA;
                *(addr2 + 0x2aa) = (uchar) 0x55;
                *(addr2 + 0x555) = (uchar) 0xA0;

                dest2[i] = data2[i];

                /* Wait for write to complete, up to 1ms */
                tcode = wait_for_DQ7((ulong) &dest2[i], data2[i], 1);

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

                /* Make sure we didn't timeout */
                if (tcode)
                        rcode = 1;
        }

        return rcode;
}

static int write_word32(flash_info_t *info, ulong dest, ulong data)
{
        vu_long *addr = (vu_long *) dest;
        ulong status;
        ulong start;
        int flag;

        /* Check if Flash is (sufficiently) erased */
        if ((*addr & data) != data)
                return 2;

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

        *addr = 0x00400040;     /* write setup */
        *addr = data;

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

        start = get_timer(0);

        while (((status = *addr) & 0x00800080) != 0x00800080) {
                WATCHDOG_RESET();
                if (get_timer(start) > CONFIG_SYS_FLASH_WRITE_TOUT) {
                        *addr = 0x00FF00FF;     /* restore read mode */
                        return 1;
                }
        }

        *addr = 0x00FF00FF;     /* restore read mode */

        return 0;
}

static int _flash_protect(flash_info_t *info, long sector)
{
        int i;
        int flag;
        ulong status;
        int rcode = 0;
        volatile long *addr = (long *)sector;

        switch (info->flash_id & FLASH_TYPEMASK) {
        case FLASH_28F320J3A:
        case FLASH_28F640J3A:
        case FLASH_28F128J3A:
                /* Disable interrupts which might cause Flash to timeout */
                flag = disable_interrupts();

                /* Issue command */
                *addr = 0x00500050L;    /* Clear the status register */
                *addr = 0x00600060L;    /* Set lock bit setup */
                *addr = 0x00010001L;    /* Set lock bit confirm */

                /* Wait for command completion */
                for (i = 0; i < 10; i++) {      /* 75us timeout, wait 100us */
                        udelay(10);
                        if ((*addr & 0x00800080L) == 0x00800080L)
                                break;
                }

                /* Not successful? */
                status = *addr;
                if (status != 0x00800080L) {
                        printf("Protect %x sector failed: %x\n",
                               (uint) sector, (uint) status);
                        rcode = 1;
                }

                /* Restore read mode */
                *addr = 0x00ff00ffL;

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

                break;
        case FLASH_AM040:       /* No soft sector protection */
                break;
        }

        /* Turn protection on for this sector */
        for (i = 0; i < info->sector_count; i++) {
                if (info->start[i] == sector) {
                        info->protect[i] = 1;
                        break;
                }
        }

        return rcode;
}

static int _flash_unprotect(flash_info_t *info, long sector)
{
        int i;
        int flag;
        ulong status;
        int rcode = 0;
        volatile long *addr = (long *) sector;

        switch (info->flash_id & FLASH_TYPEMASK) {
        case FLASH_28F320J3A:
        case FLASH_28F640J3A:
        case FLASH_28F128J3A:
                /* Disable interrupts which might cause Flash to timeout */
                flag = disable_interrupts();

                *addr = 0x00500050L;    /* Clear the status register */
                *addr = 0x00600060L;    /* Clear lock bit setup */
                *addr = 0x00D000D0L;    /* Clear lock bit confirm */

                /* Wait for command completion */
                for (i = 0; i < 80; i++) {      /* 700ms timeout, wait 800 */
                        udelay(10000);  /* Delay 10ms */
                        if ((*addr & 0x00800080L) == 0x00800080L)
                                break;
                }

                /* Not successful? */
                status = *addr;
                if (status != 0x00800080L) {
                        printf("Un-protect %x sector failed: %x\n",
                               (uint) sector, (uint) status);
                        *addr = 0x00ff00ffL;
                        rcode = 1;
                }

                /* restore read mode */
                *addr = 0x00ff00ffL;

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

                break;
        case FLASH_AM040:       /* No soft sector protection */
                break;
        }

        /*
         * Fix Intel's little red wagon.  Reprotect
         * sectors that were protected before we undid
         * protection on a specific sector.
         */
        for (i = 0; i < info->sector_count; i++) {
                if (info->start[i] != sector) {
                        if (info->protect[i]) {
                                if (_flash_protect(info, info->start[i]))
                                        rcode = 1;
                        }
                } else          /* Turn protection off for this sector */
                        info->protect[i] = 0;
        }

        return rcode;
}

int flash_real_protect(flash_info_t *info, long sector, int prot)
{
        int rcode;

        if (prot)
                rcode = _flash_protect(info, info->start[sector]);
        else
                rcode = _flash_unprotect(info, info->start[sector]);

        return rcode;
}