/*
 * (C) Copyright 2001
 * Josh Huber <huber@mclx.com>, Mission Critical Linux, Inc.
 *
 * (C) Copyright 2002
 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
 *
 * Adapted for Interphase 4539 by Wolfgang Grandegger <wg@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 <config.h>
#include <common.h>
#include <flash.h>
#include <asm/io.h>

flash_info_t    flash_info[CONFIG_SYS_MAX_FLASH_BANKS];

extern int hwc_flash_size(void);
static ulong flash_get_size (u32 addr, flash_info_t *info);
static int flash_get_offsets (u32 base, flash_info_t *info);
static int write_word (flash_info_t *info, ulong dest, ulong data);
static void flash_reset (u32 addr);

#define out8(a,v) *(volatile unsigned char*)(a) = v
#define in8(a)    *(volatile unsigned char*)(a)
#define in32(a)   *(volatile unsigned long*)(a)
#define iobarrier_rw() eieio()

unsigned long flash_init (void)
{
        unsigned int i;
        unsigned long flash_size = 0;
        unsigned long bank_size;
        unsigned int bank = 0;

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

        /* Initialise the BOOT Flash */
        if (bank == CONFIG_SYS_MAX_FLASH_BANKS) {
                puts ("Warning: not all Flashes are initialised !");
                return flash_size;
        }

        bank_size = flash_get_size (CONFIG_SYS_FLASH_BASE, flash_info + bank);
        if (bank_size) {
#if CONFIG_SYS_MONITOR_BASE >= CONFIG_SYS_FLASH_BASE && \
    CONFIG_SYS_MONITOR_BASE < CONFIG_SYS_FLASH_BASE + CONFIG_SYS_MAX_FLASH_SIZE
                /* monitor protection ON by default */
                flash_protect(FLAG_PROTECT_SET,
                              CONFIG_SYS_MONITOR_BASE,
                              CONFIG_SYS_MONITOR_BASE + monitor_flash_len - 1,
                              flash_info + bank);
#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_SECT_SIZE - 1,
                              flash_info + bank);
#endif

                /* HWC protection ON by default */
                flash_protect(FLAG_PROTECT_SET,
                              CONFIG_SYS_FLASH_BASE,
                              CONFIG_SYS_FLASH_BASE + 0x10000 - 1,
                              flash_info + bank);

                flash_size += bank_size;
                bank++;
        } else {
                puts ("Warning: the BOOT Flash is not initialised !");
        }

        return flash_size;
}

/*
 * The following code cannot be run from FLASH!
 */
static ulong flash_get_size (u32 addr, flash_info_t *info)
{
        volatile uchar value;
#if 0
        int i;
#endif

        /* Write auto select command: read Manufacturer ID */
        out8(addr + 0x0555, 0xAA);
        iobarrier_rw();
        udelay(10);
        out8(addr + 0x02AA, 0x55);
        iobarrier_rw();
        udelay(10);
        out8(addr + 0x0555, 0x90);
        iobarrier_rw();
        udelay(10);

        value = in8(addr);
        iobarrier_rw();
        udelay(10);
        switch (value | (value << 16)) {
        case AMD_MANUFACT:
                info->flash_id = FLASH_MAN_AMD;
                break;

        case FUJ_MANUFACT:
                info->flash_id = FLASH_MAN_FUJ;
                break;

        default:
                info->flash_id = FLASH_UNKNOWN;
                flash_reset (addr);
                return 0;
        }

        value = in8(addr + 1);                  /* device ID            */
        iobarrier_rw();

        switch (value) {
        case AMD_ID_LV033C:
                info->flash_id += FLASH_AM033C;
                info->size = hwc_flash_size();
                if (info->size > CONFIG_SYS_MAX_FLASH_SIZE) {
                        printf("U-Boot supports only %d MB\n",
                               CONFIG_SYS_MAX_FLASH_SIZE);
                        info->size = CONFIG_SYS_MAX_FLASH_SIZE;
                }
                info->sector_count = info->size / 0x10000;
                break;                          /* => 4 MB              */

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

        }

        if (!flash_get_offsets (addr, info)) {
                flash_reset (addr);
                return 0;
        }

#if 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 */
                value = in8(info->start[i] + 2);
                iobarrier_rw();
                info->protect[i] = (value & 1) != 0;
        }
#endif

        /*
         * Reset bank to read mode
         */
        flash_reset (addr);

        return (info->size);
}

static int flash_get_offsets (u32 base, flash_info_t *info)
{
        unsigned int i, size;

        switch (info->flash_id & FLASH_TYPEMASK) {
        case FLASH_AM033C:
                /* set sector offsets for uniform sector type   */
                size = info->size / info->sector_count;
                for (i = 0; i < info->sector_count; i++) {
                        info->start[i] = base + i * size;
                }
                break;
        default:
                return 0;
        }

        return 1;
}

int flash_erase (flash_info_t *info, int s_first, int s_last)
{
        volatile u32 addr = 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 %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");
        }

        l_sect = -1;

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

        out8(addr + 0x555, 0xAA);
        iobarrier_rw();
        out8(addr + 0x2AA, 0x55);
        iobarrier_rw();
        out8(addr + 0x555, 0x80);
        iobarrier_rw();
        out8(addr + 0x555, 0xAA);
        iobarrier_rw();
        out8(addr + 0x2AA, 0x55);
        iobarrier_rw();

        /* Start erase on unprotected sectors */
        for (sect = s_first; sect<=s_last; sect++) {
                if (info->protect[sect] == 0) { /* not protected */
                        addr = info->start[sect];
                        out8(addr, 0x30);
                        iobarrier_rw();
                        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 = info->start[l_sect];
        while ((in8(addr) & 0x80) != 0x80) {
                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;
                }
                iobarrier_rw();
        }

DONE:
        /* reset to read mode */
        flash_reset (info->start[0]);

        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 u32 addr = info->start[0];
        ulong start;
        int flag, i;

        /* Check if Flash is (sufficiently) erased */
        if ((in32(dest) & data) != data) {
                return (2);
        }
        /* Disable interrupts which might cause a timeout here */
        flag = disable_interrupts();

        /* first, perform an unlock bypass command to speed up flash writes */
        out8(addr + 0x555, 0xAA);
        iobarrier_rw();
        out8(addr + 0x2AA, 0x55);
        iobarrier_rw();
        out8(addr + 0x555, 0x20);
        iobarrier_rw();

        /* write each byte out */
        for (i = 0; i < 4; i++) {
                char *data_ch = (char *)&data;
                out8(addr, 0xA0);
                iobarrier_rw();
                out8(dest+i, data_ch[i]);
                iobarrier_rw();
                udelay(10); /* XXX */
        }

        /* we're done, now do an unlock bypass reset */
        out8(addr, 0x90);
        iobarrier_rw();
        out8(addr, 0x00);
        iobarrier_rw();

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

        /* data polling for D7 */
        start = get_timer (0);
        while ((in32(dest) & 0x80808080) != (data & 0x80808080)) {
                if (get_timer(start) > CONFIG_SYS_FLASH_WRITE_TOUT) {
                        return (1);
                }
                iobarrier_rw();
        }

        flash_reset (addr);

        return (0);
}

/*
 * Reset bank to read mode
 */
static void flash_reset (u32 addr)
{
        out8(addr, 0xF0);       /* reset bank */
        iobarrier_rw();
}

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_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_AM033C:      printf ("AM29LV033C (32 Mbit, uniform sectors)\n");
                                break;
        default:                printf ("Unknown Chip Type\n");
                                break;
        }

        if (info->size % 0x100000 == 0) {
                printf ("  Size: %ld MB in %d Sectors\n",
                        info->size / 0x100000, info->sector_count);
        }
        else if (info->size % 0x400 == 0) {
                printf ("  Size: %ld KB in %d Sectors\n",
                        info->size / 0x400, info->sector_count);
        }
        else {
                printf ("  Size: %ld B in %d Sectors\n",
                        info->size, 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");
}