/*
 * (C) Copyright 2001
 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
 *
 * Flash Routines for Intel devices
 *
 *--------------------------------------------------------------------
 * 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 <ppcboot.h>
#include <mpc8xx.h>


flash_info_t flash_info[CFG_MAX_FLASH_BANKS];

/*-----------------------------------------------------------------------
 */
ulong flash_get_size( volatile unsigned long *baseaddr, flash_info_t *info )
{
  short i;
  unsigned long flashtest_h, flashtest_l;

  info->sector_count = info->size = 0;
  info->flash_id = FLASH_UNKNOWN;

  /* Write query command sequence and test FLASH answer
   */
  baseaddr[0] = 0x00980098;
  baseaddr[1] = 0x00980098;

  flashtest_h = baseaddr[0];			/* manufacturer ID	   */
  flashtest_l = baseaddr[1];

  if (flashtest_h != INTEL_MANUFACT || flashtest_l != INTEL_MANUFACT)
    return (0);  				/* no or unknown flash	   */

  flashtest_h = baseaddr[2];			/* device ID		   */
  flashtest_l = baseaddr[3];

  if (flashtest_h != flashtest_l)
    return (0);

  switch (flashtest_h)
  {
      case INTEL_ID_28F160C3B:
        info->flash_id = FLASH_28F160C3B;
        info->sector_count = 39;
        info->size = 0x00800000;		/* 4 * 2 MB = 8 MB	   */
	break;
      case INTEL_ID_28F160F3B:
        info->flash_id = FLASH_28F160F3B;
        info->sector_count = 39;
        info->size = 0x00800000;		/* 4 * 2 MB = 8 MB	   */
	break;
      default:
        return (0);  			 	/* no or unknown flash	   */
  }

  info->flash_id |= INTEL_MANUFACT << 16;	/* set manufacturer offset */

  if (info->flash_id & FLASH_BTYPE)
  {
    volatile unsigned long *tmp = baseaddr;

    /* set up sector start adress table (bottom sector type)
     * AND unlock the sectors (if our chip is 160C3)
     */
    for (i = 0; i < info->sector_count; i++)
    {
      if ((info->flash_id & FLASH_TYPEMASK) == FLASH_28F160C3B)
      {
	  tmp[0] = 0x00600060;
	  tmp[1] = 0x00600060;
	  tmp[0] = 0x00D000D0;
	  tmp[1] = 0x00D000D0;
      }
      info->start[i] = (uint)tmp;
      tmp += i < 8 ? 0x2000 : 0x10000;		/* pointer arith	   */
    }
  }

  memset (info->protect, 0, info->sector_count);

  baseaddr[0] = 0x00FF00FF;
  baseaddr[1] = 0x00FF00FF;

  return (info->size);
}

/*-----------------------------------------------------------------------
 */
unsigned long flash_init (void)
{
    unsigned long size_b0 = 0;
    int i;

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

    /* Static FLASH Bank configuration here (only one bank) */

    size_b0 = flash_get_size((ulong *)CFG_FLASH0_BASE, &flash_info[0]);
    if (flash_info[0].flash_id == FLASH_UNKNOWN || size_b0 == 0)
    {
	printf ("## Unknown FLASH on Bank 0 - Size = 0x%08lx = %ld MB\n",
		size_b0, size_b0>>20);
    }

    /* protect monitor and environment sectors
     */

#if CFG_MONITOR_BASE >= CFG_FLASH0_BASE
    flash_protect(FLAG_PROTECT_SET,
		  CFG_MONITOR_BASE,
		  CFG_MONITOR_BASE+CFG_MONITOR_LEN-1,
		  &flash_info[0]);
#endif

#if (CFG_ENV_IS_IN_FLASH == 1) && defined(CFG_ENV_ADDR)
# ifndef  CFG_ENV_SIZE
#  define CFG_ENV_SIZE	CFG_ENV_SECT_SIZE
# endif
    flash_protect(FLAG_PROTECT_SET,
		  CFG_ENV_ADDR,
		  CFG_ENV_ADDR + CFG_ENV_SIZE - 1,
		  &flash_info[0]);
#endif

    return (size_b0);
}

/*-----------------------------------------------------------------------
 */
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 >> 16) & 0xff)
    {
    case 0x89:
	printf ("INTEL ");
	break;
    default:
	printf ("Unknown Vendor ");
	break;
    }

    switch (info->flash_id & FLASH_TYPEMASK)
    {
    case FLASH_28F160C3B:
	printf ("28F160C3B (16 M, bottom sector)\n");
	break;
    case FLASH_28F160F3B:
	printf ("28F160F3B (16 M, bottom sector)\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");
}

/*-----------------------------------------------------------------------
 */
int flash_erase (flash_info_t *info, int s_first, int s_last)
{
    int flag, prot, sect;
    ulong start, now, last;
    volatile ulong *addr;

    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;
    }

    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 erase on unprotected sectors
     */
    for (sect = s_first; sect<=s_last; sect++)
    {
	addr = (volatile unsigned long *)info->start[sect];

        start = get_timer (0);
	last = start;
	if (info->protect[sect] == 0)
        {
            /* Disable interrupts which might cause a timeout here
	     */
            flag = disable_interrupts();

	    /* Erase the block
	     */
	    addr[0] = 0x00200020;
	    addr[1] = 0x00200020;
	    addr[0] = 0x00D000D0;
	    addr[1] = 0x00D000D0;

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

            /* wait at least 80us - let's wait 1 ms
	     */
            udelay (1000);

            last  = start;
	    while ((addr[0] & 0x00800080) != 0x00800080 ||
		   (addr[1] & 0x00800080) != 0x00800080)
            {
	        if ((now = get_timer(start)) > CFG_FLASH_ERASE_TOUT)
                {
	            printf ("Timeout (erase suspended!)\n");
		    /* Suspend erase
		     */
		    addr[0] = 0x00B000B0;
		    addr[1] = 0x00B000B0;
	            goto DONE;
	        }
	        /* show that we're waiting
		 */
	        if ((now - last) > 1000)
                {	/* every second */
	            serial_putc ('.');
	            last = now;
	        }
            }
	    if (addr[0] & 0x00220022 || addr[1] & 0x00220022)
	    {
		printf ("*** ERROR: erase failed!\n");
		goto DONE;
	    }
	}
    }

    printf (" done\n");

DONE:
    /* Clear status register and reset to read mode
     */
    addr[0] = 0x00500050;
    addr[1] = 0x00500050;
    addr[0] = 0x00FF00FF;
    addr[1] = 0x00FF00FF;

    return 0;
}

static int write_word (flash_info_t *, volatile unsigned long *, ulong);

/*-----------------------------------------------------------------------
 * 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 v;
    int i, l, cc = cnt, res = 0;


    for ( ; cc > 0; addr += 4, cc -= 4 - l)
    {
        l = (addr & 3);
        addr &= ~3;

        for (i = 0; i < 4; i++)
            v = (v << 8) + (i < l || i - l >= cc ?
		*((unsigned char *)addr + i) : *src++);

        if ((res = write_word(info, (volatile unsigned long *)addr, v)) != 0)
		break;
    }

    return (res);
}

/*-----------------------------------------------------------------------
 * Write a word to Flash, returns:
 * 0 - OK
 * 1 - write timeout
 * 2 - Flash not erased
 */
static int write_word (flash_info_t *info, volatile unsigned long *addr, ulong data)
{
    int flag, res = 0;
    ulong start;

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

    *addr = 0x00400040;
    *addr = data;

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

    start = get_timer (0);
    while ((*addr & 0x00800080) != 0x00800080)
    {
	if (get_timer(start) > CFG_FLASH_WRITE_TOUT)
	{
	    /* Suspend program
	     */
	    *addr = 0x00B000B0;
	    res = 1;
	    goto OUT;
	}
    }

    if (*addr & 0x00220022)
    {
	printf("*** ERROR: program failed!\n");
	res = 1;
    }

OUT:
    /* Clear status register and reset to read mode
     */
    *addr = 0x00500050;
    *addr = 0x00FF00FF;

    return (res);
}
