/*
 * (C) Copyright 2003-2004
 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
 *
 * (C) Copyright 2004
 * Martin Krause, TQ-Systems GmbH, martin.krause@tqs.de
 *
 * Modified for the CMC PU2 by (C) Copyright 2004 Gary Jennejohn
 * garyj@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>

#ifndef CONFIG_ENV_ADDR
#define CONFIG_ENV_ADDR (CONFIG_SYS_FLASH_BASE + CONFIG_ENV_OFFSET)
#endif

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

#define FLASH_CYCLE1    0x0555
#define FLASH_CYCLE2    0x02AA

/*-----------------------------------------------------------------------
 * Functions
 */
static ulong flash_get_size(vu_short *addr, flash_info_t *info);
static void flash_reset(flash_info_t *info);
static int write_word_amd(flash_info_t *info, vu_short *dest, ushort data);
static flash_info_t *flash_get_info(ulong base);

/*-----------------------------------------------------------------------
 * flash_init()
 *
 * sets up flash_info and returns size of FLASH (bytes)
 */
unsigned long flash_init (void)
{
        unsigned long size = 0;
        ulong flashbase = CONFIG_SYS_FLASH_BASE;

        /* Init: no FLASHes known */
        memset(&flash_info[0], 0, sizeof(flash_info_t));

        flash_info[0].size = flash_get_size((vu_short *)flashbase, &flash_info[0]);

        size = flash_info[0].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_get_info(CONFIG_SYS_MONITOR_BASE));
#endif

#ifdef  CONFIG_ENV_IS_IN_FLASH
        /* ENV protection ON by default */
        flash_protect(FLAG_PROTECT_SET,
                      CONFIG_ENV_ADDR,
                      CONFIG_ENV_ADDR+CONFIG_ENV_SIZE-1,
                      flash_get_info(CONFIG_ENV_ADDR));
#endif

        return size ? size : 1;
}

/*-----------------------------------------------------------------------
 */
static void flash_reset(flash_info_t *info)
{
        vu_short *base = (vu_short *)(info->start[0]);

        /* Put FLASH back in read mode */
        if ((info->flash_id & FLASH_VENDMASK) == FLASH_MAN_INTEL)
                *base = 0x00FF; /* Intel Read Mode */
        else if ((info->flash_id & FLASH_VENDMASK) == FLASH_MAN_AMD)
                *base = 0x00F0; /* AMD Read Mode */
}

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

static flash_info_t *flash_get_info(ulong base)
{
        int i;
        flash_info_t * info;

        info = NULL;
        for (i = 0; i < CONFIG_SYS_MAX_FLASH_BANKS; i ++) {
                info = & flash_info[i];
                if (info->size && info->start[0] <= base &&
                    base <= info->start[0] + info->size - 1)
                        break;
        }

        return i == CONFIG_SYS_MAX_FLASH_BANKS ? 0 : info;
}

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

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_AMD:     printf ("AMD ");                break;
        case FLASH_MAN_BM:      printf ("BRIGHT MICRO ");       break;
        case FLASH_MAN_FUJ:     printf ("FUJITSU ");            break;
        case FLASH_MAN_SST:     printf ("SST ");                break;
        case FLASH_MAN_STM:     printf ("STM ");                break;
        case FLASH_MAN_INTEL:   printf ("INTEL ");              break;
        default:                printf ("Unknown Vendor ");     break;
        }

        switch (info->flash_id & FLASH_TYPEMASK) {
        case FLASH_S29GL064M:
                printf ("S29GL064M-R6 (64Mbit, uniform sector size)\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!
 */

ulong flash_get_size (vu_short *addr, flash_info_t *info)
{
        int i;
        ushort value;
        ulong base = (ulong)addr;

        /* Write auto select command sequence */
        addr[FLASH_CYCLE1] = 0x00AA;    /* for AMD, Intel ignores this */
        addr[FLASH_CYCLE2] = 0x0055;    /* for AMD, Intel ignores this */
        addr[FLASH_CYCLE1] = 0x0090;    /* selects Intel or AMD */

        /* read Manufacturer ID */
        udelay(100);
        value = addr[0];
        debug ("Manufacturer ID: %04X\n", value);

        switch (value) {

        case (AMD_MANUFACT & 0xFFFF):
                debug ("Manufacturer: AMD (Spansion)\n");
                info->flash_id = FLASH_MAN_AMD;
                break;

        case (INTEL_MANUFACT & 0xFFFF):
                debug ("Manufacturer: Intel (not supported yet)\n");
                info->flash_id = FLASH_MAN_INTEL;
                break;

        default:
                printf ("Unknown Manufacturer ID: %04X\n", value);
                info->flash_id = FLASH_UNKNOWN;
                info->sector_count = 0;
                info->size = 0;
                goto out;
        }

        value = addr[1];
        debug ("Device ID: %04X\n", value);

        switch (addr[1]) {

        case (AMD_ID_MIRROR & 0xFFFF):
                debug ("Mirror Bit flash: addr[14] = %08X  addr[15] = %08X\n",
                        addr[14], addr[15]);

                switch(addr[14]) {
                case (AMD_ID_GL064M_2 & 0xFFFF):
                        if (addr[15] != (AMD_ID_GL064M_3 & 0xffff)) {
                                printf ("Chip: S29GLxxxM -> unknown\n");
                                info->flash_id = FLASH_UNKNOWN;
                                info->sector_count = 0;
                                info->size = 0;
                        } else {
                                debug ("Chip: S29GL064M-R6\n");
                                info->flash_id += FLASH_S29GL064M;
                                info->sector_count = 128;
                                info->size = 0x00800000;
                                for (i = 0; i < info->sector_count; i++) {
                                        info->start[i] = base;
                                        base += 0x10000;
                                }
                        }
                        break;  /* => 16 MB     */
                default:
                        printf ("Chip: *** unknown ***\n");
                        info->flash_id = FLASH_UNKNOWN;
                        info->sector_count = 0;
                        info->size = 0;
                        break;
                }
                break;

        default:
                printf ("Unknown Device ID: %04X\n", value);
                info->flash_id = FLASH_UNKNOWN;
                info->sector_count = 0;
                info->size = 0;
                break;
        }

out:
        /* Put FLASH back in read mode */
        flash_reset(info);

        return (info->size);
}

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

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

        debug ("flash_erase: first: %d last: %d\n", s_first, s_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 %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");
        }

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

        /*
         * Start erase on unprotected sectors.
         * Since the flash can erase multiple sectors with one command
         * we take advantage of that by doing the erase in chunks of
         * 3 sectors.
         */
        for (sect = s_first; sect <= s_last; ) {
                l_sect = -1;

                addr[FLASH_CYCLE1] = 0x00AA;
                addr[FLASH_CYCLE2] = 0x0055;
                addr[FLASH_CYCLE1] = 0x0080;
                addr[FLASH_CYCLE1] = 0x00AA;
                addr[FLASH_CYCLE2] = 0x0055;

                /* do the erase in chunks of at most 3 sectors */
                for (ssect = 0; ssect < 3; ssect++) {
                        if ((sect + ssect) > s_last)
                                break;
                        if (info->protect[sect + ssect] == 0) { /* not protected */
                                addr = (vu_short *)(info->start[sect + ssect]);
                                addr[0] = 0x0030;
                                l_sect = sect + ssect;
                        }
                }
                /* wait at least 80us - let's wait 1 ms */
                udelay (1000);

                /*
                 * We wait for the last triggered sector
                 */
                if (l_sect < 0)
                        goto DONE;

                reset_timer_masked ();
                last  = 0;
                addr = (vu_short *)(info->start[l_sect]);
                while ((addr[0] & 0x0080) != 0x0080) {
                        if ((now = get_timer_masked ()) > CONFIG_SYS_FLASH_ERASE_TOUT) {
                                printf ("Timeout\n");
                                return 1;
                        }
                        /* show that we're waiting */
                        if ((now - last) > 1000) {      /* every second */
                                putc ('.');
                                last = now;
                        }
                }
                addr = (vu_short *)info->start[0];
                addr[0] = 0x00F0;       /* reset bank */
                sect += ssect;
        }

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

DONE:
        /* reset to read mode */
        addr = (vu_short *)info->start[0];
        addr[0] = 0x00F0;       /* 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 wp, data;
        int rc;

        if (addr & 1) {
                printf ("unaligned destination not supported\n");
                return ERR_ALIGN;
        };

        if ((int) src & 1) {
                printf ("unaligned source not supported\n");
                return ERR_ALIGN;
        };

        wp = addr;

        while (cnt >= 2) {
                data = *((vu_short *)src);
                if ((rc = write_word_amd(info, (vu_short *)wp, data)) != 0) {
printf ("write_buff 1: write_word_amd() rc=%d\n", rc);
                        return (rc);
                }
                src += 2;
                wp += 2;
                cnt -= 2;
        }

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

        if (cnt == 1) {
                data = (*((volatile u8 *) src)) | (*((volatile u8 *) (wp + 1)) << 8);
                if ((rc = write_word_amd(info, (vu_short *)wp, data)) != 0) {
printf ("write_buff 1: write_word_amd() rc=%d\n", rc);
                        return (rc);
                }
                src += 1;
                wp += 1;
                cnt -= 1;
        }

        return ERR_OK;
}

/*-----------------------------------------------------------------------
 * Write a word to Flash for AMD FLASH
 * A word is 16 or 32 bits, whichever the bus width of the flash bank
 * (not an individual chip) is.
 *
 * returns:
 * 0 - OK
 * 1 - write timeout
 * 2 - Flash not erased
 */
static int write_word_amd (flash_info_t *info, vu_short *dest, ushort data)
{
        int flag;
        vu_short *base;         /* first address in flash bank  */

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

        base = (vu_short *)(info->start[0]);

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

        base[FLASH_CYCLE1] = 0x00AA;    /* unlock */
        base[FLASH_CYCLE2] = 0x0055;    /* unlock */
        base[FLASH_CYCLE1] = 0x00A0;    /* selects program mode */

        *dest = data;           /* start programming the data   */

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

        reset_timer_masked ();

        /* data polling for D7 */
        while ((*dest & 0x0080) != (data & 0x0080)) {
                if (get_timer_masked () > CONFIG_SYS_FLASH_WRITE_TOUT) {
                        *dest = 0x00F0; /* reset bank */
                        return (1);
                }
        }
        return (0);
}