/*
 * (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 + monitor_flash_len - 1,
			&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)
{
	u32 * volatile addr = (u32 * volatile)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);
}