/*
 * (C) Copyright 2002
 * Daniel Engström, Omicron Ceti AB, daniel@omicron.se
 *
 * (C) Copyright 2002
 * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
 * Alex Zuepke <azu@sysgo.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/io.h>

ulong myflush(void);


#define SC520_MAX_FLASH_BANKS  3
#define SC520_FLASH_BANK0_BASE 0x38000000  /* BOOTCS */
#define SC520_FLASH_BANK1_BASE 0x30000000  /* ROMCS0 */
#define SC520_FLASH_BANK2_BASE 0x28000000  /* ROMCS1 */
#define SC520_FLASH_BANKSIZE   0x8000000

#define AMD29LV016_SIZE        0x200000
#define AMD29LV016_SECTORS     32

flash_info_t    flash_info[SC520_MAX_FLASH_BANKS];

#define CMD_READ_ARRAY		0x00F000F0
#define CMD_UNLOCK1		0x00AA00AA
#define CMD_UNLOCK2		0x00550055
#define CMD_ERASE_SETUP		0x00800080
#define CMD_ERASE_CONFIRM	0x00300030
#define CMD_PROGRAM		0x00A000A0
#define CMD_UNLOCK_BYPASS	0x00200020


#define BIT_ERASE_DONE		0x00800080
#define BIT_RDY_MASK		0x00800080
#define BIT_PROGRAM_ERROR	0x00200020
#define BIT_TIMEOUT		0x80000000 /* our flag */

#define READY 1
#define ERR   2
#define TMO   4

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

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

	for (i = 0; i < SC520_MAX_FLASH_BANKS; i++) {
		ulong flashbase = 0;
		int sectsize = 0;
		if (i==0 || i==2) {
			/* FixMe: this assumes that bank 0 and 2
			 * are mapped to the two 8Mb banks */
			flash_info[i].flash_id =
				(AMD_MANUFACT & FLASH_VENDMASK) |
				(AMD_ID_LV016B & FLASH_TYPEMASK);

			flash_info[i].size = AMD29LV016_SIZE*4;
			flash_info[i].sector_count = AMD29LV016_SECTORS;
			sectsize = (AMD29LV016_SIZE*4)/AMD29LV016_SECTORS;
		} else {
			/* FixMe: this assumes that bank1 is unmapped
			 * (or mapped to the same flash bank as BOOTCS) */
			flash_info[i].flash_id = 0;
			flash_info[i].size = 0;
			flash_info[i].sector_count = 0;
			sectsize=0;
		}
		memset(flash_info[i].protect, 0, CFG_MAX_FLASH_SECT);
		switch (i) {
		case 0:
			flashbase = SC520_FLASH_BANK0_BASE;
			break;
		case 1:
			flashbase = SC520_FLASH_BANK1_BASE;
			break;
		case 2:
			flashbase = SC520_FLASH_BANK0_BASE;
			break;
		default:
			panic("configured too many flash banks!\n");
		}

		for (j = 0; j < flash_info[i].sector_count; j++) {
			flash_info[i].start[j] = sectsize;
			flash_info[i].start[j] = flashbase + j * sectsize;
		}
		size += flash_info[i].size;
	}

	/*
	 * Protect monitor and environment sectors
	 */
	flash_protect(FLAG_PROTECT_SET,
		      i386boot_start-SC520_FLASH_BANK0_BASE,
		      i386boot_end-SC520_FLASH_BANK0_BASE,
		      &flash_info[0]);

#ifdef CFG_ENV_ADDR
	flash_protect(FLAG_PROTECT_SET,
		      CFG_ENV_ADDR,
		      CFG_ENV_ADDR + CFG_ENV_SIZE - 1,
		      &flash_info[0]);
#endif
	return size;
}

/*-----------------------------------------------------------------------
 */
void flash_print_info(flash_info_t *info)
{
	int i;

	switch (info->flash_id & FLASH_VENDMASK) {
	case (AMD_MANUFACT & FLASH_VENDMASK):
		printf("AMD: ");
		break;
	default:
		printf("Unknown Vendor ");
		break;
	}

	switch (info->flash_id & FLASH_TYPEMASK) {
	case (AMD_ID_LV016B & FLASH_TYPEMASK):
		printf("4x Amd29LV016B (16Mbit)\n");
		break;
	default:
		printf("Unknown Chip Type\n");
		goto done;
		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");

	done:
}

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

int flash_erase(flash_info_t *info, int s_first, int s_last)
{
	ulong result;
	int iflag, prot, sect;
	int rc = ERR_OK;
	int chip1, chip2;

	/* first look for protection bits */

	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) !=
	    (AMD_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.
	 */
	iflag = 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();

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

			writel(CMD_UNLOCK1, addr + 1);
			writel(CMD_UNLOCK2, addr + 2);
			writel(CMD_ERASE_SETUP, addr + 1);

			writel(CMD_UNLOCK1, addr + 1);
			writel(CMD_UNLOCK2, addr + 2);
			writel(CMD_ERASE_CONFIRM, addr);


			/* wait until flash is ready */
			chip1 = chip2 = 0;

			do {
				result = readl(addr);

				/* check timeout */
				if (get_timer(0) > CFG_FLASH_ERASE_TOUT) {
					writel(CMD_READ_ARRAY, addr + 1);
					chip1 = TMO;
					break;
				}

				if (!chip1 && (result & 0xFFFF) & BIT_ERASE_DONE) {
					chip1 = READY;
				}

				if (!chip1 && (result & 0xFFFF) & BIT_PROGRAM_ERROR) {
					chip1 = ERR;
				}

				if (!chip2 && (result >> 16) & BIT_ERASE_DONE) {
					chip2 = READY;
				}

				if (!chip2 && (result >> 16) & BIT_PROGRAM_ERROR) {
					chip2 = ERR;
				}

			}  while (!chip1 || !chip2);

			writel(CMD_READ_ARRAY, addr + 1);

			if (chip1 == ERR || chip2 == ERR) {
				rc = ERR_PROG_ERROR;
				goto outahere;
			}

			if (chip1 == TMO) {
				rc = ERR_TIMOUT;
				goto outahere;
			}

			printf("ok.\n");
		} else { /* it was protected */

			printf("protected!\n");
		}
	}

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

outahere:
	/* allow flash to settle - wait 10 ms */
	udelay(10000);

	if (iflag) {
		enable_interrupts();
	}

	return rc;
}

/*-----------------------------------------------------------------------
 * Copy memory to flash
 */

volatile static int write_word(flash_info_t *info, ulong dest, ulong data)
{
	ulong addr = dest;
	ulong result;
	int rc = ERR_OK;
	int iflag;
	int chip1, chip2;

	/*
	 * Check if Flash is (sufficiently) erased
	 */
	result = readl(addr);
	if ((result & 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.
	 */
	iflag = disable_interrupts();

	writel(CMD_UNLOCK1, addr + 1);
	writel(CMD_UNLOCK2, addr + 2);
	writel(CMD_UNLOCK_BYPASS, addr + 1);
	writel(addr, CMD_PROGRAM);
	writel(addr, data);

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

	/* wait until flash is ready */
	chip1 = chip2 = 0;
	do {
		result = readl(addr);

		/* check timeout */
		if (get_timer(0) > CFG_FLASH_ERASE_TOUT) {
			chip1 = ERR | TMO;
			break;
		}

		if (!chip1 && ((result & 0x80) == (data & 0x80))) {
			chip1 = READY;
		}

		if (!chip1 && ((result & 0xFFFF) & BIT_PROGRAM_ERROR)) {
			result = readl(addr);

			if ((result & 0x80) == (data & 0x80)) {
				chip1 = READY;
			} else {
				chip1 = ERR;
			}
		}

		if (!chip2 && ((result & (0x80 << 16)) == (data & (0x80 << 16)))) {
			chip2 = READY;
		}

		if (!chip2 && ((result >> 16) & BIT_PROGRAM_ERROR)) {
			result = readl(addr);

			if ((result & (0x80 << 16)) == (data & (0x80 << 16))) {
				chip2 = READY;
			} else {
				chip2 = ERR;
			}
		}

	}  while (!chip1 || !chip2);

	writel(CMD_READ_ARRAY, addr);

	if (chip1 == ERR || chip2 == ERR || readl(addr) != data) {
		rc = ERR_PROG_ERROR;
	}

	if (iflag) {
		enable_interrupts();
	}

	return rc;
}

/*-----------------------------------------------------------------------
 * Copy memory to flash.
 */

int write_buff(flash_info_t *info, uchar *src, ulong addr, ulong cnt)
{
	ulong cp, wp, data;
	int l;
	int i, 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 << 24);
		}
		for (; i<4 && cnt>0; ++i) {
			data = (data >> 8) | (*src++ << 24);
			--cnt;
			++cp;
		}
		for (; cnt==0 && i<4; ++i, ++cp) {
			data = (data >> 8) | (*(uchar *)cp << 24);
		}

		if ((rc = write_word(info, wp, data)) != 0) {
			return rc;
		}
		wp += 4;
	}

	/*
	 * handle word aligned part
	 */
	while (cnt >= 4) {
		data = *((vu_long*)src);
		if ((rc = write_word(info, wp, data)) != 0) {
			return rc;
		}
		src += 4;
		wp  += 4;
		cnt -= 4;
	}

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

	/*
	 * handle unaligned tail bytes
	 */
	data = 0;
	for (i=0, cp=wp; i<4 && cnt>0; ++i, ++cp) {
		data = (data >> 8) | (*src++ << 24);
		--cnt;
	}
	for (; i<4; ++i, ++cp) {
		data = (data >> 8) | (*(uchar *)cp << 24);
	}

	return write_word(info, wp, data);
}
