/*
 * (C) Copyright 2002
 * Kyle Harris, Nexus Technologies, Inc. kharris@nexus-tech.net
 *
 * (C) Copyright 2002
 * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
 * Marius Groeger <mgroeger@sysgo.de>
 *
 * (C) Copyright 2002
 * Robert Schwebel, Pengutronix, <r.schwebel@pengutronix.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 <asm/arch/pxa-regs.h>

#define FLASH_BANK_SIZE 0x02000000
#define MAIN_SECT_SIZE  0x40000         /* 2x16 = 256k per sector */

flash_info_t    flash_info[CFG_MAX_FLASH_BANKS];


/**
 * flash_init: - initialize data structures for flash chips
 *
 * @return: size of the flash
 */

ulong flash_init(void)
{
    int i, j;
    ulong size = 0;

	for (i = 0; i < CFG_MAX_FLASH_BANKS; i++) {
	ulong flashbase = 0;
	flash_info[i].flash_id =
	  (INTEL_MANUFACT & FLASH_VENDMASK) |
	  (INTEL_ID_28F128J3 & FLASH_TYPEMASK);
	flash_info[i].size = FLASH_BANK_SIZE;
	flash_info[i].sector_count = CFG_MAX_FLASH_SECT;
	memset(flash_info[i].protect, 0, CFG_MAX_FLASH_SECT);

		switch (i) {
           case 0:
	        flashbase = PHYS_FLASH_1;
                break;
           default:
	        panic("configured to many flash banks!\n");
                break;
        }
		for (j = 0; j < flash_info[i].sector_count; j++) {
	    flash_info[i].start[j] = flashbase + j*MAIN_SECT_SIZE;
	}
	size += flash_info[i].size;
    }

	/* Protect monitor and environment sectors */
    flash_protect(FLAG_PROTECT_SET,
		  CFG_FLASH_BASE,
		  CFG_FLASH_BASE + _armboot_end_data - _armboot_start,
		  &flash_info[0]);

    flash_protect(FLAG_PROTECT_SET,
		  CFG_ENV_ADDR,
		  CFG_ENV_ADDR + CFG_ENV_SIZE - 1,
		  &flash_info[0]);

    return size;
}


/**
 * flash_print_info: - print information about the flash situation
 *
 * @param info: 
 */

void flash_print_info  (flash_info_t *info)
{
    int i, j;

	for (j=0; j<CFG_MAX_FLASH_BANKS; j++) {

		switch (info->flash_id & FLASH_VENDMASK) {

        case (INTEL_MANUFACT & FLASH_VENDMASK):
	        printf("Intel: ");
	        break;
        default:
	        printf("Unknown Vendor ");
	        break;
        }

		switch (info->flash_id & FLASH_TYPEMASK) {

        case (INTEL_ID_28F128J3 & FLASH_TYPEMASK):
	        printf("28F128J3 (128Mbit)\n");
	        break;
        default:
	        printf("Unknown Chip Type\n");
				return;
        }

        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");
        info++;
    }
}


/**
 * flash_erase: - erase flash sectors
 *
 */

int	flash_erase (flash_info_t *info, int s_first, int s_last)
{
    int flag, prot, sect;
    int rc = ERR_OK;

    if (info->flash_id == FLASH_UNKNOWN)
	return ERR_UNKNOWN_FLASH_TYPE;

    if ((s_first < 0) || (s_first > s_last)) {
	return ERR_INVAL;
    }

	if ((info->flash_id & FLASH_VENDMASK) != (INTEL_MANUFACT & FLASH_VENDMASK))
	return ERR_UNKNOWN_FLASH_VENDOR;

    prot = 0;
    for (sect=s_first; sect<=s_last; ++sect) {
		if (info->protect[sect]) prot++;
	}

	if (prot) return ERR_PROTECTED;

    /*
     * 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.
     */
    flag = disable_interrupts();

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

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

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

	if (info->protect[sect] == 0) {	/* not protected */
			u32 * volatile addr = (u32 * volatile)(info->start[sect]);

			/* erase sector:                                    */
			/* The strata flashs are aligned side by side on    */
			/* the data bus, so we have to write the commands   */
			/* to both chips here:                              */

			*addr = 0x00200020;	/* erase setup */
			*addr = 0x00D000D0;	/* erase confirm */

			while ((*addr & 0x00800080) != 0x00800080) {
		if (get_timer_masked() > CFG_FLASH_ERASE_TOUT) {
					*addr = 0x00B000B0; /* suspend erase*/
					*addr = 0x00FF00FF; /* read mode    */
		    rc = ERR_TIMOUT;
		    goto outahere;
		}
	    }

			*addr = 0x00500050; /* clear status register cmd.   */
			*addr = 0x00FF00FF; /* resest to read mode          */

	}
		
	printf("ok.\n");
    }

	if (ctrlc()) printf("User Interrupt!\n");

outahere:

    /* allow flash to settle - wait 10 ms */
    udelay_masked(10000);

	if (flag) enable_interrupts();

    return rc;
}


/**
 * write_word: - copy memory to flash
 * 
 * @param info:
 * @param dest:
 * @param data: 
 * @return:
 */

static int write_word (flash_info_t *info, ulong dest, ushort data)
{
    ushort *addr = (ushort *)dest, val;
    int rc = ERR_OK;
    int flag;

	/* Check if Flash is (sufficiently) erased */
	if ((*addr & data) != data) return ERR_NOT_ERASED;

    /*
     * 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.
     */
    flag = disable_interrupts();

    /* clear status register command */
    *addr = 0x50;

    /* program set-up command */
    *addr = 0x40;

    /* latch address/data */
    *addr = data;

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

    /* wait while polling the status register */
	while(((val = *addr) & 0x80) != 0x80) {
	if (get_timer_masked() > CFG_FLASH_WRITE_TOUT) {
	    rc = ERR_TIMOUT;
			*addr = 0xB0; /* suspend program command */
	    goto outahere;
	}
    }

    if(val & 0x1A) {	/* check for error */
        printf("\nFlash write error %02x at address %08lx\n",
    	   (int)val, (unsigned long)dest);
        if(val & (1<<3)) {
	    printf("Voltage range error.\n");
	    rc = ERR_PROG_ERROR;
	    goto outahere;
        }
        if(val & (1<<1)) {
	    printf("Device protect error.\n");
	    rc = ERR_PROTECTED;
	    goto outahere;
        }
        if(val & (1<<4)) {
	    printf("Programming error.\n");
	    rc = ERR_PROG_ERROR;
	    goto outahere;
        }
        rc = ERR_PROG_ERROR;
        goto outahere;
    }

outahere:

	*addr = 0xFF; /* read array command */
	if (flag) enable_interrupts();

    return rc;
}


/**
 * write_buf: - Copy memory to flash.
 * 
 * @param info:	 
 * @param src:	source of copy transaction
 * @param addr:	where to copy to
 * @param cnt: 	number of bytes to copy
 *
 * @return	error code
 */

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

    wp = (addr & ~1);	/* 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 << 8);
	}
	for (; i<2 && cnt>0; ++i) {
	    data = (data >> 8) | (*src++ << 8);
	    --cnt;
	    ++cp;
	}
	for (; cnt==0 && i<2; ++i, ++cp) {
	    data = (data >> 8) | (*(uchar *)cp << 8);
	}

	if ((rc = write_word(info, wp, data)) != 0) {
	    return (rc);
	}
	wp += 2;
    }

    /*
     * handle word aligned part
     */
    while (cnt >= 2) {
	/* data = *((vushort*)src); */
	data = *((ushort*)src);
	if ((rc = write_word(info, wp, data)) != 0) {
	    return (rc);
	}
	src += 2;
	wp  += 2;
	cnt -= 2;
    }

	if (cnt == 0) return ERR_OK;

    /*
     * handle unaligned tail bytes
     */
    data = 0;
    for (i=0, cp=wp; i<2 && cnt>0; ++i, ++cp) {
	data = (data >> 8) | (*src++ << 8);
	--cnt;
    }
    for (; i<2; ++i, ++cp) {
	data = (data >> 8) | (*(uchar *)cp << 8);
    }

    return write_word(info, wp, data);
}