/*
 * (C) Copyright 2001
 * Kyle Harris, Nexus Technologies, Inc. kharris@nexus-tech.net
 *
 * (C) Copyright 2001
 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
 *
 * Modified for the MP2USB by (C) Copyright 2005 Eric Benard
 * ebenard@eukrea.com
 *
 * 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 <linux/byteorder/swab.h>

#define CONFIG_SYS_MAX_FLASH_BANKS      1
#define PHYS_FLASH_SECT_SIZE    0x00020000 /* 128 KB sectors (x1) */

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

#define FLASH_PORT_WIDTH        ushort
#define FLASH_PORT_WIDTHV       vu_short
#define SWAP(x)                 __swab16(x)

#define FPW                     FLASH_PORT_WIDTH
#define FPWV                    FLASH_PORT_WIDTHV

#define mb() __asm__ __volatile__ ("" : : : "memory")

/* Intel-compatible flash commands */
#define INTEL_PROGRAM   0x00100010
#define INTEL_ERASE     0x00200020
#define INTEL_PROG      0x00400040
#define INTEL_CLEAR     0x00500050
#define INTEL_LOCKBIT   0x00600060
#define INTEL_PROTECT   0x00010001
#define INTEL_STATUS    0x00700070
#define INTEL_READID    0x00900090
#define INTEL_SUSPEND   0x00B000B0
#define INTEL_CONFIRM   0x00D000D0
#define INTEL_RESET     0xFFFFFFFF

/* Intel-compatible flash status bits */
#define INTEL_FINISHED  0x00800080
#define INTEL_OK        0x00800080

/*-----------------------------------------------------------------------
 * Functions
 */
static ulong flash_get_size (FPW *addr, flash_info_t *info);
static int write_data (flash_info_t *info, ulong dest, FPW data);
static void flash_get_offsets (ulong base, flash_info_t *info);
void inline spin_wheel (void);

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

unsigned long flash_init (void)
{
        int i;
        ulong size = 0;

        for (i = 0; i < CONFIG_SYS_MAX_FLASH_BANKS; i++) {
                switch (i) {
                case 0:
                        flash_get_size ((FPW *) PHYS_FLASH_1, &flash_info[i]);
                        flash_get_offsets (PHYS_FLASH_1, &flash_info[i]);
                        break;
                default:
                        panic ("configured too many flash banks!\n");
                        break;
                }
                size += flash_info[i].size;
        }

        /* Protect monitor and environment sectors
         */
        flash_protect ( FLAG_PROTECT_SET,
                        CONFIG_SYS_FLASH_BASE,
                        CONFIG_SYS_FLASH_BASE + monitor_flash_len - 1,
                        &flash_info[0] );

        flash_protect ( FLAG_PROTECT_SET,
                        CONFIG_ENV_ADDR,
                        CONFIG_ENV_ADDR + CONFIG_ENV_SIZE - 1, &flash_info[0] );

        return size;
}

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

        if (info->flash_id == FLASH_UNKNOWN) {
                return;
        }

        if ((info->flash_id & FLASH_VENDMASK) == FLASH_MAN_INTEL) {
                for (i = 0; i < info->sector_count; i++) {
                        info->start[i] = base + (i * PHYS_FLASH_SECT_SIZE);
                        info->protect[i] = 0;
                }
        }
}

/*-----------------------------------------------------------------------
 */
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;
        default:
                printf ("Unknown Vendor ");
                break;
        }

        switch (info->flash_id & FLASH_TYPEMASK) {
        case FLASH_28F640J3A:
                printf ("28F640J3A\n");
                break;
        case FLASH_28F128J3A:
                printf ("28F128J3A\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!
 */
static ulong flash_get_size (FPW *addr, flash_info_t *info)
{
        volatile FPW value;

        /* Write auto select command: read Manufacturer ID */
        addr[0x5555] = (FPW) 0x00AA00AA;
        addr[0x2AAA] = (FPW) 0x00550055;
        addr[0x5555] = (FPW) 0x00900090;

        mb ();
        value = addr[0];

        switch (value) {

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

        default:
                info->flash_id = FLASH_UNKNOWN;
                info->sector_count = 0;
                info->size = 0;
                addr[0] = (FPW) INTEL_RESET;    /* restore read mode */
                return (0);                     /* no or unknown flash  */
        }

        mb ();
        value = addr[1];                        /* device ID        */

        switch (value) {

        case (FPW) INTEL_ID_28F640J3A:
                info->flash_id += FLASH_28F640J3A;
                info->sector_count = 64;
                info->size = 0x00800000;
                break;                          /* => 8 MB     */

        case (FPW) INTEL_ID_28F128J3A:
                info->flash_id += FLASH_28F128J3A;
                info->sector_count = 128;
                info->size = 0x01000000;
                break;                          /* => 16 MB     */

        default:
                info->flash_id = FLASH_UNKNOWN;
                break;
        }

        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;
        }

        addr[0] = (FPW) INTEL_RESET;            /* restore read mode */

        return (info->size);
}


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

int flash_erase (flash_info_t *info, int s_first, int s_last)
{
        int prot, sect;
        ulong type, start, last;
        int rcode = 0;
        int cflag, iflag;

        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;
        }

        type = (info->flash_id & FLASH_VENDMASK);
        if ((type != FLASH_MAN_INTEL)) {
                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");
        }

        start = get_timer (0);
        last = start;

        /*
         * Disable interrupts which might cause a timeout
         * here. Remember that our exception vectors are
         * at address 0 in the flash, and we don't want a
         * (ticker) exception to happen while the flash
         * chip is in programming mode.
         */
        cflag = icache_status ();
        icache_disable ();
        /* Disable interrupts which might cause a timeout here */
        iflag = disable_interrupts ();

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

                        printf ("Erasing sector %2d ... ", sect);

                        /* arm simple, non interrupt dependent timer */
                        reset_timer_masked ();

                        *addr = (FPW) INTEL_CLEAR;      /* clear status register */
                        *addr = (FPW) INTEL_ERASE;      /* erase setup */
                        *addr = (FPW) INTEL_CONFIRM;    /* erase confirm */

                        while (((status = *addr) & (FPW) INTEL_FINISHED) != (FPW) INTEL_FINISHED) {
                                if (get_timer_masked () > CONFIG_SYS_FLASH_ERASE_TOUT) {
                                        printf ("Timeout\n");
                                        *addr = (FPW) INTEL_SUSPEND;    /* suspend erase     */
                                        *addr = (FPW) INTEL_RESET;      /* reset to read mode */
                                        rcode = 1;
                                        break;
                                }
                        }

                        *addr = (FPWV)INTEL_CLEAR;      /* clear status register cmd.   */
                        *addr = (FPWV)INTEL_RESET;      /* resest to read mode          */

                        printf (" done\n");
                }
        }

        if (iflag)
                enable_interrupts ();

        if (cflag)
                icache_enable ();

        return rcode;
}

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

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

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

        /* get lower word aligned address */
        wp = (addr & ~1);
        port_width = 2;

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

                if ((rc = write_data (info, wp, SWAP (data))) != 0) {
                        return (rc);
                }
                wp += port_width;
        }

        /*
         * handle word aligned part
         */
        count = 0;
        while (cnt >= port_width) {
                data = 0;
                for (i = 0; i < port_width; ++i) {
                        data = (data << 8) | *src++;
                }
                if ((rc = write_data (info, wp, SWAP (data))) != 0) {
                        return (rc);
                }
                wp += port_width;
                cnt -= port_width;
                if (count++ > 0x800) {
                        spin_wheel ();
                        count = 0;
                }
        }

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

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

        return (write_data (info, wp, SWAP (data)));
}

/*-----------------------------------------------------------------------
 * Write a word or halfword to Flash, returns:
 * 0 - OK
 * 1 - write timeout
 * 2 - Flash not erased
 */
static int write_data (flash_info_t *info, ulong dest, FPW data)
{
        FPWV *addr = (FPWV *) dest;
        ulong status;
        int cflag, iflag;

        /* Check if Flash is (sufficiently) erased */
        if ((*addr & data) != data) {
                printf ("not erased at %08lx (%lx)\n", (ulong) addr, (ulong) *addr);
                return (2);
        }
        /*
         * Disable interrupts which might cause a timeout
         * here. Remember that our exception vectors are
         * at address 0 in the flash, and we don't want a
         * (ticker) exception to happen while the flash
         * chip is in programming mode.
         */
        cflag = icache_status ();
        icache_disable ();
        /* Disable interrupts which might cause a timeout here */
        iflag = disable_interrupts ();

        *addr = (FPW) INTEL_PROG;       /* write setup */
        *addr = data;

        /* arm simple, non interrupt dependent timer */
        reset_timer_masked ();

        /* wait while polling the status register */
        while (((status = *addr) & (FPW) INTEL_FINISHED) != (FPW) INTEL_FINISHED) {
                if (get_timer_masked () > CONFIG_SYS_FLASH_WRITE_TOUT) {
                        *addr = (FPW) INTEL_RESET;      /* restore read mode */
                        return (1);
                }
        }

        *addr = (FPW) INTEL_RESET;      /* restore read mode */

        if (iflag)
                enable_interrupts ();

        if (cflag)
                icache_enable ();

        return (0);
}

void inline spin_wheel (void)
{
        static int p = 0;
        static char w[] = "\\/-";

        printf ("\010%c", w[p]);
        (++p == 3) ? (p = 0) : 0;
}

/*-----------------------------------------------------------------------
 * Set/Clear sector's lock bit, returns:
 * 0 - OK
 * 1 - Error (timeout, voltage problems, etc.)
 */
int flash_real_protect(flash_info_t *info, long sector, int prot)
{
        int i;
        int rc = 0;
        FPWV *addr = (FPWV *)(info->start[sector]);
        int flag = disable_interrupts();

        *addr = (FPW) INTEL_CLEAR;      /* Clear status register */
        if (prot) {                     /* Set sector lock bit */
                *addr = (FPW) INTEL_LOCKBIT;    /* Sector lock bit */
                *addr = (FPW) INTEL_PROTECT;    /* set */
        }
        else {                          /* Clear sector lock bit */
                *addr = (FPW) INTEL_LOCKBIT;    /* All sectors lock bits */
                *addr = (FPW) INTEL_CONFIRM;    /* clear */
        }

        reset_timer_masked ();

        while ((*addr & (FPW) INTEL_FINISHED) != (FPW) INTEL_FINISHED) {
                if (get_timer_masked () > CONFIG_SYS_FLASH_UNLOCK_TOUT) {
                        printf("Flash lock bit operation timed out\n");
                        rc = 1;
                        break;
                }
        }

        if (*addr != (FPW) INTEL_OK) {
                printf("Flash lock bit operation failed at %08X, CSR=%08X\n",
                       (uint)addr, (uint)*addr);
                rc = 1;
        }

        if (!rc)
                info->protect[sector] = prot;

        /*
         * Clear lock bit command clears all sectors lock bits, so
         * we have to restore lock bits of protected sectors.
         */
        if (!prot)
        {
                for (i = 0; i < info->sector_count; i++)
                {
                        if (info->protect[i])
                        {
                                reset_timer_masked ();
                                addr = (FPWV *) (info->start[i]);
                                *addr = (FPW) INTEL_LOCKBIT;    /* Sector lock bit */
                                *addr = (FPW) INTEL_PROTECT;    /* set */
                                while ((*addr & (FPW) INTEL_FINISHED) != (FPW) INTEL_FINISHED)
                                {
                                        if (get_timer_masked () > CONFIG_SYS_FLASH_UNLOCK_TOUT)
                                        {
                                                printf("Flash lock bit operation timed out\n");
                                                rc = 1;
                                                break;
                                        }
                                }
                        }
                }
        }

        if (flag)
                enable_interrupts();

        *addr = (FPW) INTEL_RESET;              /* Reset to read array mode */

        return rc;
}