/*
 * (C) Copyright 2003, Dan Malek, Embedded Edge, LLC.  <dan@embeddededge.com>
 * Copied from ADS85xx.
 * Updated to support the Silicon Tx GP3 8560.  We should only find
 * two Intel 28F640 parts in 16-bit mode (i.e. 32-bit wide flash),
 * but I left other code here in case people order custom boards.
 *
 * (C) Copyright 2003 Motorola Inc.
 *  Xianghua Xiao,(X.Xiao@motorola.com)
 *
 * (C) Copyright 2000, 2001
 *  Wolfgang Denk, DENX Software Engineering, wd@denx.de.
 *
 * (C) Copyright 2001, Stuart Hughes, Lineo Inc, stuarth@lineo.com
 * Add support the Sharp chips on the mpc8260ads.
 * I started with board/ip860/flash.c and made changes I found in
 * the MTD project by David Schleef.
 *
 * 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>

#if !defined(CONFIG_SYS_NO_FLASH)

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

#if defined(CONFIG_ENV_IS_IN_FLASH)
# ifndef  CONFIG_ENV_ADDR
#  define CONFIG_ENV_ADDR       (CONFIG_SYS_FLASH_BASE + CONFIG_ENV_OFFSET)
# endif
# ifndef  CONFIG_ENV_SIZE
#  define CONFIG_ENV_SIZE       CONFIG_ENV_SECT_SIZE
# endif
# ifndef  CONFIG_ENV_SECT_SIZE
#  define CONFIG_ENV_SECT_SIZE  CONFIG_ENV_SIZE
# endif
#endif

#undef DEBUG

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

unsigned long flash_init (void)
{
        unsigned long size;
        int i;

        /* Init: enable write,
         * or we cannot even write flash commands
         */
        for (i=0; i<CONFIG_SYS_MAX_FLASH_BANKS; ++i) {
                flash_info[i].flash_id = FLASH_UNKNOWN;

                /* set the default sector offset */
        }

        /* Static FLASH Bank configuration here - FIXME XXX */

        size = flash_get_size((vu_long *)CONFIG_SYS_FLASH_BASE, &flash_info[0]);

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

        /* Re-do sizing to get full correct info */
        size = flash_get_size((vu_long *)CONFIG_SYS_FLASH_BASE, &flash_info[0]);

        flash_info[0].size = size;

#if CONFIG_SYS_MONITOR_BASE >= CONFIG_SYS_FLASH_BASE
        /* monitor protection ON by default */
        flash_protect(FLAG_PROTECT_SET,
                      CONFIG_SYS_MONITOR_BASE,
                      CONFIG_SYS_MONITOR_BASE+monitor_flash_len-1,
                      &flash_info[0]);

#ifdef  CONFIG_ENV_IS_IN_FLASH
        /* ENV protection ON by default */
        flash_protect(FLAG_PROTECT_SET,
                      CONFIG_ENV_ADDR,
                      CONFIG_ENV_ADDR+CONFIG_ENV_SECT_SIZE-1,
                      &flash_info[0]);
#endif
#endif
        return (size);
}

/*-----------------------------------------------------------------------
 */
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_INTEL:   printf ("Intel ");              break;
        case FLASH_MAN_SHARP:   printf ("Sharp ");              break;
        default:                printf ("Unknown Vendor ");     break;
        }

        switch (info->flash_id & FLASH_TYPEMASK) {
        case FLASH_28F640C3T:   printf ("28F640C3T (64 Mbit x 2, 128 x 128k)\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");
}

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

static ulong flash_get_size (vu_long *addr, flash_info_t *info)
{
        short i;
        ulong value;
        ulong base = (ulong)addr;
        ulong sector_offset;

#ifdef DEBUG
        printf("Check flash at 0x%08x\n",(uint)addr);
#endif
        /* Write "Intelligent Identifier" command: read Manufacturer ID */
        *addr = 0x90909090;
        udelay(20);
        asm("sync");

        value = addr[0] & 0x00FF00FF;

#ifdef DEBUG
        printf("manufacturer=0x%x\n",(uint)value);
#endif
        switch (value) {
        case MT_MANUFACT:       /* SHARP, MT or => Intel */
        case INTEL_ALT_MANU:
                info->flash_id = FLASH_MAN_INTEL;
                break;
        default:
                printf("unknown manufacturer: %x\n", (unsigned int)value);
                info->flash_id = FLASH_UNKNOWN;
                info->sector_count = 0;
                info->size = 0;
                return (0);                     /* no or unknown flash  */
        }

        value = addr[1];             /* device ID            */

#ifdef DEBUG
        printf("deviceID=0x%x\n",(uint)value);
#endif
        switch (value) {

        case (INTEL_ID_28F640C3T):
                info->flash_id += FLASH_28F640C3T;
                info->sector_count = 135;
                info->size = 0x01000000;
                sector_offset = 0x20000;
                break;                          /* => 2x8 MB            */

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

        }

        /* set up sector start address table
         * The first 127 blocks are large, the last 8 are small.
         */
        for (i = 0; i < 127; i++) {
                info->start[i] = base;
                base += sector_offset;
                /* Sectors are locked upon reset */
                info->protect[i] = 0;
        }
        for (i = 127; i < 135; i++) {
                info->start[i] = base;
                base += 0x4000;
                /* Sectors are locked upon reset */
                info->protect[i] = 0;
        }


        /*
         * Prevent writes to uninitialized FLASH.
         */
        if (info->flash_id != FLASH_UNKNOWN) {
                addr = (vu_long *)info->start[0];
                *addr = 0xFFFFFF;       /* reset bank to read array mode */
                asm("sync");
        }

        return (info->size);
}


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

int     flash_erase (flash_info_t *info, int s_first, int s_last)
{
        int flag, prot, 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_VENDMASK) != FLASH_MAN_INTEL)
             && ((info->flash_id & FLASH_VENDMASK) != FLASH_MAN_SHARP) ) {
                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");
        }

#ifdef DEBUG
        printf("\nFlash Erase:\n");
#endif
        /* Make Sure Block Lock Bit is not set. */
        if(clear_block_lock_bit((vu_long *)(info->start[s_first]))){
                return 1;
        }

        /* Start erase on unprotected sectors */
#if defined(DEBUG)
        printf("Begin to erase now,s_first=0x%x s_last=0x%x...\n",s_first,s_last);
#endif
        for (sect = s_first; sect<=s_last; sect++) {
                if (info->protect[sect] == 0) { /* not protected */
                        vu_long *addr = (vu_long *)(info->start[sect]);
                        asm("sync");

                        last = start = get_timer (0);

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

                        /* Reset Array */
                        *addr = 0xffffffff;
                        asm("sync");
                        /* Clear Status Register */
                        *addr = 0x50505050;
                        asm("sync");
                        /* Single Block Erase Command */
                        *addr = 0x20202020;
                        asm("sync");
                        /* Confirm */
                        *addr = 0xD0D0D0D0;
                        asm("sync");

                        if((info->flash_id & FLASH_TYPEMASK) != FLASH_LH28F016SCT) {
                            /* Resume Command, as per errata update */
                            *addr = 0xD0D0D0D0;
                            asm("sync");
                        }

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

                        /* wait at least 80us - let's wait 1 ms */
                        udelay (1000);
                        while ((*addr & 0x00800080) != 0x00800080) {
                                if(*addr & 0x00200020){
                                        printf("Error in Block Erase - Lock Bit may be set!\n");
                                        printf("Status Register = 0x%X\n", (uint)*addr);
                                        *addr = 0xFFFFFFFF;     /* reset bank */
                                        asm("sync");
                                        return 1;
                                }
                                if ((now=get_timer(start)) > CONFIG_SYS_FLASH_ERASE_TOUT) {
                                        printf ("Timeout\n");
                                        *addr = 0xFFFFFFFF;     /* reset bank */
                                        asm("sync");
                                        return 1;
                                }
                                /* show that we're waiting */
                                if ((now - last) > 1000) {      /* every second */
                                        putc ('.');
                                        last = now;
                                }
                        }

                        /* reset to read mode */
                        *addr = 0xFFFFFFFF;
                        asm("sync");
                }
        }

        printf ("flash erase 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)
{
        vu_long *addr = (vu_long *)dest;
        ulong start, csr;
        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();

        /* Write Command */
        *addr = 0x10101010;
        asm("sync");

        /* Write Data */
        *addr = data;

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

        /* data polling for D7 */
        start = get_timer (0);
        flag  = 0;

        while (((csr = *addr) & 0x00800080) != 0x00800080) {
                if (get_timer(start) > CONFIG_SYS_FLASH_WRITE_TOUT) {
                        flag = 1;
                        break;
                }
        }
        if (csr & 0x40404040) {
                printf ("CSR indicates write error (%08lx) at %08lx\n", csr, (ulong)addr);
                flag = 1;
        }

        /* Clear Status Registers Command */
        *addr = 0x50505050;
        asm("sync");
        /* Reset to read array mode */
        *addr = 0xFFFFFFFF;
        asm("sync");

        return (flag);
}

/*-----------------------------------------------------------------------
 * Clear Block Lock Bit, returns:
 * 0 - OK
 * 1 - Timeout
 */

static int clear_block_lock_bit(vu_long  * addr)
{
        ulong start, now;

        /* Reset Array */
        *addr = 0xffffffff;
        asm("sync");
        /* Clear Status Register */
        *addr = 0x50505050;
        asm("sync");

        *addr = 0x60606060;
        asm("sync");
        *addr = 0xd0d0d0d0;
        asm("sync");

        start = get_timer (0);
        while((*addr & 0x00800080) != 0x00800080){
                if ((now=get_timer(start)) > CONFIG_SYS_FLASH_ERASE_TOUT) {
                        printf ("Timeout on clearing Block Lock Bit\n");
                        *addr = 0xFFFFFFFF;     /* reset bank */
                        asm("sync");
                        return 1;
                }
        }
        return 0;
}

#endif /* !CONFIG_SYS_NO_FLASH */