/*
 * (C) Copyright 2003
 * 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>

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

/* NOTE - CONFIG_FLASH_16BIT means the CPU interface is 16-bit, it
 *        has nothing to do with the flash chip being 8-bit or 16-bit.
 */
#ifdef CONFIG_FLASH_16BIT
typedef unsigned short FLASH_PORT_WIDTH;
typedef volatile unsigned short FLASH_PORT_WIDTHV;
#define FLASH_ID_MASK   0xFFFF
#else
typedef unsigned char FLASH_PORT_WIDTH;
typedef volatile unsigned char FLASH_PORT_WIDTHV;
#define FLASH_ID_MASK   0xFF
#endif

#define FPW     FLASH_PORT_WIDTH
#define FPWV    FLASH_PORT_WIDTHV

#define ORMASK(size) ((-size) & OR_AM_MSK)

#define FLASH_CYCLE1    0x0555
#define FLASH_CYCLE2    0x02aa

/*-----------------------------------------------------------------------
 * Functions
 */
static ulong flash_get_size(FPWV *addr, flash_info_t *info);
static void flash_reset(flash_info_t *info);
static int write_word_amd(flash_info_t *info, FPWV *dest, FPW 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;
        int i;
        extern void flash_preinit(void);
        extern void flash_afterinit(ulong);
        ulong flashbase = CONFIG_SYS_FLASH_BASE;

        flash_preinit();

        /* Init: no FLASHes known */
        for (i=0; i < CONFIG_SYS_MAX_FLASH_BANKS; ++i) {
                memset(&flash_info[i], 0, sizeof(flash_info_t));

                flash_info[i].size =
                        flash_get_size((FPW *)flashbase, &flash_info[i]);

                size += flash_info[i].size;
                flashbase += 0x800000;
        }
#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


        flash_afterinit(size);
        return size ? size : 1;
}

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

        /* Put FLASH back in read mode */
        if ((info->flash_id & FLASH_VENDMASK) == FLASH_MAN_INTEL)
                *base = (FPW)0x00FF00FF;        /* Intel Read Mode */
        else if ((info->flash_id & FLASH_VENDMASK) == FLASH_MAN_AMD)
                *base = (FPW)0x00F000F0;        /* AMD Read Mode */
}

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

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

        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;
        uchar *boottype;
        uchar *bootletter;
        char *fmt;
        uchar botbootletter[] = "B";
        uchar topbootletter[] = "T";
        uchar botboottype[] = "bottom boot sector";
        uchar topboottype[] = "top boot sector";

        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;
        }

        /* check for top or bottom boot, if it applies */
        if (info->flash_id & FLASH_BTYPE) {
                boottype = botboottype;
                bootletter = botbootletter;
        }
        else {
                boottype = topboottype;
                bootletter = topbootletter;
        }

        switch (info->flash_id & FLASH_TYPEMASK) {
        case FLASH_AMDLV065D:
                fmt = "29LV065 (64 Mbit, uniform sectors)\n";
                break;
        default:
                fmt = "Unknown Chip Type\n";
                break;
        }

        printf (fmt, bootletter, boottype);

        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!
 */

ulong flash_get_size (FPWV *addr, flash_info_t *info)
{
        int i;
        FPWV* addr2;

        /* Write auto select command: read Manufacturer ID */
        /* Write auto select command sequence and test FLASH answer */
        addr[FLASH_CYCLE1] = (FPW)0x00AA00AA;   /* for AMD, Intel ignores this */
        addr[FLASH_CYCLE2] = (FPW)0x00550055;   /* for AMD, Intel ignores this */
        addr[FLASH_CYCLE1] = (FPW)0x00900090;   /* selects Intel or AMD */

        /* The manufacturer codes are only 1 byte, so just use 1 byte.
         * This works for any bus width and any FLASH device width.
         */
        udelay(100);
        switch (addr[0] & 0xff) {

        case (uchar)AMD_MANUFACT:
                info->flash_id = FLASH_MAN_AMD;
                break;

        case (uchar)INTEL_MANUFACT:
                info->flash_id = FLASH_MAN_INTEL;
                break;

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

        /* Check 16 bits or 32 bits of ID so work on 32 or 16 bit bus. */
        if (info->flash_id != FLASH_UNKNOWN) switch ((FPW)addr[1]) {

        case (FPW)AMD_ID_LV065D:
                info->flash_id += FLASH_AMDLV065D;
                info->sector_count = 128;
                info->size = 0x00800000;
                for( i = 0; i < info->sector_count; i++ )
                        info->start[i] = (ulong)addr + (i * 0x10000);
                break;                          /* => 8 or 16 MB        */

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

        /* test for real flash at bank 1 */
        addr2 = (FPW *)((ulong)addr | 0x800000);
        if (addr2 != addr &&
                ((addr2[0] & 0xff) == (addr[0] & 0xff)) && ((FPW)addr2[1] == (FPW)addr[1])) {
                /* Seems 2 banks are the same space (8Mb chip is installed,
                 * J24 in default position (CS0)). Disable this (first) bank.
                 */
                info->flash_id = FLASH_UNKNOWN;
                info->sector_count = 0;
                info->size = 0;
        }
        /* 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)
{
        FPWV *addr;
        int flag, prot, sect;
        int intel = (info->flash_id & FLASH_VENDMASK) == FLASH_MAN_INTEL;
        ulong start, now, last;
        int rcode = 0;

        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;
        }

        switch (info->flash_id & FLASH_TYPEMASK) {
        case FLASH_AMDLV065D:
                break;
        case FLASH_UNKNOWN:
        default:
                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");
        }

        last  = get_timer(0);

        /* Start erase on unprotected sectors */
        for (sect = s_first; sect<=s_last && rcode == 0; sect++) {

                if (info->protect[sect] != 0)   /* protected, skip it */
                        continue;

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

                addr = (FPWV *)(info->start[sect]);
                if (intel) {
                        *addr = (FPW)0x00500050; /* clear status register */
                        *addr = (FPW)0x00200020; /* erase setup */
                        *addr = (FPW)0x00D000D0; /* erase confirm */
                }
                else {
                        /* must be AMD style if not Intel */
                        FPWV *base;             /* first address in bank */

                        base = (FPWV *)(info->start[0]);
                        base[FLASH_CYCLE1] = (FPW)0x00AA00AA;   /* unlock */
                        base[FLASH_CYCLE2] = (FPW)0x00550055;   /* unlock */
                        base[FLASH_CYCLE1] = (FPW)0x00800080;   /* erase mode */
                        base[FLASH_CYCLE1] = (FPW)0x00AA00AA;   /* unlock */
                        base[FLASH_CYCLE2] = (FPW)0x00550055;   /* unlock */
                        *addr = (FPW)0x00300030;        /* erase sector */
                }

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

                start = get_timer(0);

                /* wait at least 50us for AMD, 80us for Intel.
                 * Let's wait 1 ms.
                 */
                udelay (1000);

                while ((*addr & (FPW)0x00800080) != (FPW)0x00800080) {
                        if ((now = get_timer(start)) > CONFIG_SYS_FLASH_ERASE_TOUT) {
                                printf ("Timeout\n");

                                if (intel) {
                                        /* suspend erase        */
                                        *addr = (FPW)0x00B000B0;
                                }

                                flash_reset(info);      /* reset to read mode */
                                rcode = 1;              /* failed */
                                break;
                        }

                        /* show that we're waiting */
                        if ((get_timer(last)) > CONFIG_SYS_HZ) {/* every second */
                                putc ('.');
                                last = get_timer(0);
                        }
                }

                /* show that we're waiting */
                if ((get_timer(last)) > CONFIG_SYS_HZ) {        /* every second */
                        putc ('.');
                        last = get_timer(0);
                }

                flash_reset(info);      /* reset to read mode   */
        }

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

/*-----------------------------------------------------------------------
 * 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)
{
        FPW data = 0; /* 16 or 32 bit word, matches flash bus width on MPC8XX */
        int bytes;        /* number of bytes to program in current word         */
        int left;         /* number of bytes left to program                    */
        int i, res;

        for (left = cnt, res = 0;
                 left > 0 && res == 0;
                 addr += sizeof(data), left -= sizeof(data) - bytes) {

                bytes = addr & (sizeof(data) - 1);
                addr &= ~(sizeof(data) - 1);

                /* combine source and destination data so can program
                 * an entire word of 16 or 32 bits
                 */
                for (i = 0; i < sizeof(data); i++) {
                        data <<= 8;
                        if (i < bytes || i - bytes >= left )
                                data += *((uchar *)addr + i);
                        else
                                data += *src++;
                }

                /* write one word to the flash */
                switch (info->flash_id & FLASH_VENDMASK) {
                case FLASH_MAN_AMD:
                        res = write_word_amd(info, (FPWV *)addr, data);
                        break;
                default:
                        /* unknown flash type, error! */
                        printf ("missing or unknown FLASH type\n");
                        res = 1;        /* not really a timeout, but gives error */
                        break;
                }
        }

        return (res);
}

/*-----------------------------------------------------------------------
 * 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, FPWV *dest, FPW data)
{
        ulong start;
        int flag;
        int res = 0;    /* result, assume success       */
        FPWV *base;             /* first address in flash bank  */

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


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

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

        base[FLASH_CYCLE1] = (FPW)0x00AA00AA;   /* unlock */
        base[FLASH_CYCLE2] = (FPW)0x00550055;   /* unlock */
        base[FLASH_CYCLE1] = (FPW)0x00A000A0;   /* selects program mode */

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

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

        start = get_timer (0);

        /* data polling for D7 */
        while (res == 0 && (*dest & (FPW)0x00800080) != (data & (FPW)0x00800080)) {
                if (get_timer(start) > CONFIG_SYS_FLASH_WRITE_TOUT) {
                        *dest = (FPW)0x00F000F0;        /* reset bank */
                        res = 1;
                }
        }

        return (res);
}
#endif /*CONFIG_FLASH_CFI_DRIVER*/