/*
 * (C) Copyright 2001
 * Kyle Harris, Nexus Technologies, Inc. kharris@nexus-tech.net
 *
 * (C) Copyright 2001
 * 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>
#include <mpc8xx.h>

flash_info_t	flash_info[CFG_MAX_FLASH_BANKS]; /* info for FLASH chips	*/
extern u_long  *my_sernum;		/* from nx823.c */

/*-----------------------------------------------------------------------
 * Protection Flags:
 */
#define FLAG_PROTECT_SET	0x01
#define FLAG_PROTECT_CLEAR	0x02

/* Board support for 1 or 2 flash devices */
#undef FLASH_PORT_WIDTH32
#define FLASH_PORT_WIDTH16

#ifdef FLASH_PORT_WIDTH16
#define FLASH_PORT_WIDTH		ushort
#define FLASH_PORT_WIDTHV		vu_short
#else
#define FLASH_PORT_WIDTH		ulong
#define FLASH_PORT_WIDTHV		vu_long
#endif

#define FPW		FLASH_PORT_WIDTH
#define FPWV	FLASH_PORT_WIDTHV

/*-----------------------------------------------------------------------
 * 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);

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

unsigned long flash_init (void)
{
	volatile immap_t     *immap  = (immap_t *)CFG_IMMR;
	volatile memctl8xx_t *memctl = &immap->im_memctl;
	unsigned long size_b0;
	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 - FIXME XXX */
	size_b0 = flash_get_size((FPW *)FLASH_BASE0_PRELIM, &flash_info[0]);

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

	/* Remap FLASH according to real size */
	memctl->memc_or0 = CFG_OR_TIMING_FLASH | (-size_b0 & 0xFFFF8000);
	memctl->memc_br0 = (CFG_FLASH_BASE & BR_BA_MSK) | BR_PS_16 | BR_MS_GPCM | BR_V;

	/* Re-do sizing to get full correct info */
	size_b0 = flash_get_size((FPW *)CFG_FLASH_BASE, &flash_info[0]);

	flash_get_offsets (CFG_FLASH_BASE, &flash_info[0]);

	/* monitor protection ON by default */
	(void)flash_protect(FLAG_PROTECT_SET,
			    CFG_FLASH_BASE,
			    CFG_FLASH_BASE+CFG_MONITOR_LEN-1,
			    &flash_info[0]);

	flash_info[0].size = size_b0;

	return (size_b0);
}

/*-----------------------------------------------------------------------
 */
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 * 0x00020000);
		}
	}
}

/*-----------------------------------------------------------------------
 */
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_28F320J3A:
				printf ("28F320J3A\n"); break;
   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)
{
	FPW value;

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

	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)0x00FF00FF;      /* restore read mode */
		return (0);			/* no or unknown flash	*/
	}

	value = addr[1];			/* device ID		*/

   switch (value) {
   case (FPW)INTEL_ID_28F320J3A:
      info->flash_id += FLASH_28F320J3A;
      info->sector_count = 32;
      info->size = 0x00400000;
      break;            /* => 4 MB     */

   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 > CFG_MAX_FLASH_SECT) {
		printf ("** ERROR: sector count %d > max (%d) **\n",
			info->sector_count, CFG_MAX_FLASH_SECT);
		info->sector_count = CFG_MAX_FLASH_SECT;
	}

	addr[0] = (FPW)0x00FF00FF;      /* restore read mode */

	return (info->size);
}


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

int	flash_erase (flash_info_t *info, int s_first, int s_last)
{
	int flag, prot, sect;
	ulong type, 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;
	}

	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;
	/* 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;

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

			*addr = (FPW)0x00500050;	/* clear status register */
			*addr = (FPW)0x00200020;	/* erase setup */
			*addr = (FPW)0x00D000D0;	/* erase confirm */

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

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

			while (((status = *addr) & (FPW)0x00800080) != (FPW)0x00800080) {
				if ((now=get_timer(start)) > CFG_FLASH_ERASE_TOUT) {
					printf ("Timeout\n");
					*addr = (FPW)0x00B000B0; /* suspend erase	  */
					*addr = (FPW)0x00FF00FF; /* reset to read mode */
					rcode = 1;
					break;
				}

				/* show that we're waiting */
			if ((now - last) > 1000) {	/* every second */
					putc ('.');
					last = now;
				}
			}

			*addr = (FPW)0x00FF00FF;	/* reset to read mode */
			printf (" done\n");
		}
	}
	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 */
#ifdef FLASH_PORT_WIDTH16
	wp = (addr & ~1);
	port_width = 2;
#else
	wp = (addr & ~3);
	port_width = 4;
#endif

	/* save sernum if needed */
	if (addr >= CFG_FLASH_SN_SECTOR && addr < CFG_FLASH_SN_BASE)
	{
		u_long dest = CFG_FLASH_SN_BASE;
		u_short *sn = (u_short *)my_sernum;

		printf("(saving sernum)");
		for (i=0; i<4; i++)
		{
			if ((rc = write_data(info, dest, sn[i])) != 0) {
				return (rc);
			}
			dest += port_width;
		}
	}

	/*
	 * 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, 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, data)) != 0) {
			return (rc);
		}
		wp  += port_width;
		cnt -= port_width;
		if (count++ > 0x800)
		{
			putc('.');
			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, 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;
	ulong start;
	int flag;

	/* Check if Flash is (sufficiently) erased */
	if ((*addr & data) != data) {
		printf("not erased at %08lx (%x)\n",(ulong)addr,*addr);
		return (2);
	}
	/* Disable interrupts which might cause a timeout here */
	flag = disable_interrupts();

	*addr = (FPW)0x00400040;		/* write setup */
	*addr = data;

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

	start = get_timer (0);

	while (((status = *addr) & (FPW)0x00800080) != (FPW)0x00800080) {
		if (get_timer(start) > CFG_FLASH_WRITE_TOUT) {
			*addr = (FPW)0x00FF00FF;	/* restore read mode */
			return (1);
		}
	}

	*addr = (FPW)0x00FF00FF;	/* restore read mode */

	return (0);
}