/*
 * (C) Copyright 2000
 * 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 <mpc8xx.h>

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

/*-----------------------------------------------------------------------
 * 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 void flash_get_offsets (ulong base, flash_info_t *info);

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

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

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

        /* Detect size */
        size_b0 = flash_get_size((vu_long *)CONFIG_SYS_FLASH_BASE, &flash_info[0]);

        /* Setup offsets */
        flash_get_offsets (CONFIG_SYS_FLASH_BASE, &flash_info[0]);

#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]);
#endif

        size_b1 = 0 ;

        flash_info[1].flash_id = FLASH_UNKNOWN;
        flash_info[1].sector_count = -1;

        flash_info[0].size = size_b0;
        flash_info[1].size = size_b1;

        return (size_b0 + size_b1);
}

/*-----------------------------------------------------------------------
 * Fix this to support variable sector sizes
*/
static void flash_get_offsets (ulong base, flash_info_t *info)
{
        int i;

        /* set up sector start address table */
        if ((info->flash_id & FLASH_TYPEMASK) == FLASH_AM040) {
                /* set sector offsets for bottom boot block type        */
                for (i = 0; i < info->sector_count; i++)
                        info->start[i] = base + (i * 0x00010000);
        }
}

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

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

        switch (info->flash_id & FLASH_VENDMASK)
        {
                case FLASH_MAN_AMD:     printf ("AMD ");                break;
                case FLASH_MAN_FUJ:     printf ("FUJITSU ");            break;
                case FLASH_MAN_BM:      printf ("BRIGHT MICRO ");       break;
                default:                printf ("Unknown Vendor ");     break;
        }

        switch (info->flash_id & FLASH_TYPEMASK)
        {
                case FLASH_AM040:       printf ("29F040 or 29LV040 (4 Mbit, uniform sectors)\n");
                        break;
                case FLASH_AM400B:      printf ("AM29LV400B (4 Mbit, bottom boot sect)\n");
                                        break;
                case FLASH_AM400T:      printf ("AM29LV400T (4 Mbit, top boot sector)\n");
                                        break;
                case FLASH_AM800B:      printf ("AM29LV800B (8 Mbit, bottom boot sect)\n");
                                        break;
                case FLASH_AM800T:      printf ("AM29LV800T (8 Mbit, top boot sector)\n");
                                        break;
                case FLASH_AM160B:      printf ("AM29LV160B (16 Mbit, bottom boot sect)\n");
                                        break;
                case FLASH_AM160T:      printf ("AM29LV160T (16 Mbit, top boot sector)\n");
                                        break;
                case FLASH_AM320B:      printf ("AM29LV320B (32 Mbit, bottom boot sect)\n");
                                        break;
                case FLASH_AM320T:      printf ("AM29LV320T (32 Mbit, top boot sector)\n");
                                        break;
                default:                printf ("Unknown Chip Type\n");
                                        break;
        }

        if (info->size >> 20) {
            printf ("  Size: %ld MB in %d Sectors\n",
                info->size >> 20,
                info->sector_count);
        } else {
            printf ("  Size: %ld KB in %d Sectors\n",
                info->size >> 10,
                info->sector_count);
        }

        puts ("  Sector Start Addresses:");

        for (i=0; i<info->sector_count; ++i)
        {
                if ((i % 5) == 0)
                {
                        puts ("\n   ");
                }

                printf (" %08lX%s",
                        info->start[i],
                        info->protect[i] ? " (RO)" : "     ");
        }

        putc ('\n');
        return;
}
/*-----------------------------------------------------------------------
 */

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

static ulong flash_get_size (vu_long *addr, flash_info_t *info)
{
        short i;
        volatile unsigned char *caddr;
        char value;

        caddr = (volatile unsigned char *)addr ;

        /* Write auto select command: read Manufacturer ID */

#if 0
        printf("Base address is: %08x\n", caddr);
#endif

        caddr[0x0555] = 0xAA;
        caddr[0x02AA] = 0x55;
        caddr[0x0555] = 0x90;

        value = caddr[0];

#if 0
        printf("Manufact ID: %02x\n", value);
#endif
        switch (value)
        {
                case 0x1: /* AMD_MANUFACT */
                        info->flash_id = FLASH_MAN_AMD;
                break;

                case 0x4: /* FUJ_MANUFACT */
                        info->flash_id = FLASH_MAN_FUJ;
                break;

                default:
                        info->flash_id = FLASH_UNKNOWN;
                        info->sector_count = 0;
                        info->size = 0;
                        break;
        }

        value = caddr[1];                       /* device ID            */
#if 0
        printf("Device ID: %02x\n", value);
#endif
        switch (value)
        {
                case AMD_ID_LV040B:
                        info->flash_id += FLASH_AM040;
                        info->sector_count = 8;
                        info->size = 0x00080000;
                        break;                          /* => 512Kb             */

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

        }

        flash_get_offsets ((ulong)addr, &flash_info[0]);

        /* check for protected sectors */
        for (i = 0; i < info->sector_count; i++)
        {
                /* read sector protection at sector address, (A7 .. A0) = 0x02 */
                /* D0 = 1 if protected */
                caddr = (volatile unsigned char *)(info->start[i]);
                info->protect[i] = caddr[2] & 1;
        }

        /*
         * Prevent writes to uninitialized FLASH.
         */
        if (info->flash_id != FLASH_UNKNOWN)
        {
                caddr = (volatile unsigned char *)info->start[0];
                *caddr = 0xF0;  /* reset bank */
        }

        return (info->size);
}


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

int     flash_erase (flash_info_t *info, int s_first, int s_last)
{
        volatile unsigned char *addr = (volatile unsigned char *)(info->start[0]);
        int flag, prot, sect, l_sect;
        ulong start, now, last;

        if ((s_first < 0) || (s_first > s_last)) {
                if (info->flash_id == FLASH_UNKNOWN) {
                        printf ("- missing\n");
                } else {
                        printf ("- no sectors to erase\n");
                }
                return 1;
        }

        if ((info->flash_id == FLASH_UNKNOWN) ||
            (info->flash_id > FLASH_AMD_COMP)) {
                printf ("Can't erase unknown flash type - aborted\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] = 0xAA;
        addr[0x02AA] = 0x55;
        addr[0x0555] = 0x80;
        addr[0x0555] = 0xAA;
        addr[0x02AA] = 0x55;

        /* Start erase on unprotected sectors */
        for (sect = s_first; sect<=s_last; sect++) {
                if (info->protect[sect] == 0) { /* not protected */
                        addr = (volatile unsigned char *)(info->start[sect]);
                        addr[0] = 0x30;
                        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 = (volatile unsigned char *)(info->start[l_sect]);

        while ((addr[0] & 0xFF) != 0xFF)
        {
                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 */
                        putc ('.');
                        last = now;
                }
        }

DONE:
        /* reset to read mode */
        addr = (volatile unsigned char *)info->start[0];

        addr[0] = 0xF0; /* reset bank */

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

/*-----------------------------------------------------------------------
 * Copy memory to flash, returns:
 * 0 - OK
 * 1 - write timeout
 * 2 - Flash not erased
 */

int write_buff (flash_info_t *info, uchar *src, ulong addr, ulong cnt)
{
        ulong cp, wp, data;
        int i, l, rc;

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

        /*
         * handle unaligned start bytes
         */
        if ((l = addr - wp) != 0) {
                data = 0;
                for (i=0, cp=wp; i<l; ++i, ++cp) {
                        data = (data << 8) | (*(uchar *)cp);
                }
                for (; i<4 && cnt>0; ++i) {
                        data = (data << 8) | *src++;
                        --cnt;
                        ++cp;
                }
                for (; cnt==0 && i<4; ++i, ++cp) {
                        data = (data << 8) | (*(uchar *)cp);
                }

                if ((rc = write_word(info, wp, data)) != 0) {
                        return (rc);
                }
                wp += 4;
        }

        /*
         * handle word aligned part
         */
        while (cnt >= 4) {
                data = 0;
                for (i=0; i<4; ++i) {
                        data = (data << 8) | *src++;
                }
                if ((rc = write_word(info, wp, data)) != 0) {
                        return (rc);
                }
                wp  += 4;
                cnt -= 4;
        }

        if (cnt == 0) {
                return (0);
        }

        /*
         * handle unaligned tail bytes
         */
        data = 0;
        for (i=0, cp=wp; i<4 && cnt>0; ++i, ++cp) {
                data = (data << 8) | *src++;
                --cnt;
        }
        for (; i<4; ++i, ++cp) {
                data = (data << 8) | (*(uchar *)cp);
        }

        return (write_word(info, wp, data));
}

/*-----------------------------------------------------------------------
 * Write a word to Flash, returns:
 * 0 - OK
 * 1 - write timeout
 * 2 - Flash not erased
 */
static int write_word (flash_info_t *info, ulong dest, ulong data)
{
        volatile unsigned char *addr = (volatile unsigned char*)(info->start[0]),
                                *cdest,*cdata;
        ulong start;
        int flag, count = 4 ;

        cdest = (volatile unsigned char *)dest ;
        cdata = (volatile unsigned char *)&data ;

        /* Check if Flash is (sufficiently) erased */
        if ((*((vu_long *)dest) & data) != data) {
                return (2);
        }

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

            addr[0x0555] = 0xAA;
            addr[0x02AA] = 0x55;
            addr[0x0555] = 0xA0;

            *cdest = *cdata;

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

            /* data polling for D7 */
            start = get_timer (0);
            while ((*cdest ^ *cdata) & 0x80)
            {
                if (get_timer(start) > CONFIG_SYS_FLASH_WRITE_TOUT) {
                        return (1);
                }
            }

            cdata++ ;
            cdest++ ;
        }
        return (0);
}

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