u-boot-imx/board/Marvell/common/flash.c

/*
 * (C) Copyright 2001
 * Josh Huber <huber@mclx.com>, Mission Critical Linux, Inc.
 *
 * SPDX-License-Identifier:	GPL-2.0+
 */

/*
 * flash.c - flash support for the 512k, 8bit boot flash
	and the 8MB 32bit extra flash on the DB64360
 *           most of this file was based on the existing U-Boot
 *           flash drivers.
 *
 * written or collected and sometimes rewritten by
 * Ingo Assmus <ingo.assmus@keymile.com>
 *
 */

#include <common.h>
#include <mpc8xx.h>
#include "../include/mv_gen_reg.h"
#include "../include/memory.h"
#include "intel_flash.h"

#define FLASH_ROM       0xFFFD	/* unknown flash type                   */
#define FLASH_RAM       0xFFFE	/* unknown flash type                   */
#define FLASH_MAN_UNKNOWN 0xFFFF0000

/* #define DEBUG */

/* Intel flash commands */
int flash_erase_intel (flash_info_t * info, int s_first, int s_last);
int write_word_intel (bank_addr_t addr, bank_word_t value);

flash_info_t flash_info[CONFIG_SYS_MAX_FLASH_BANKS];	/* info for FLASH chips */

/*-----------------------------------------------------------------------
 * Functions
 */
static ulong flash_get_size (int portwidth, vu_long * addr,
			     flash_info_t * info);
static int write_word (flash_info_t * info, ulong dest, ulong data);
static void flash_get_offsets (ulong base, flash_info_t * info);

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

unsigned long flash_init (void)
{
	unsigned int i;
	unsigned long size_b0 = 0, size_b1 = 0;
	unsigned long base, flash_size;

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

	/* the boot flash */
	base = CONFIG_SYS_FLASH_BASE;
	size_b0 =
		flash_get_size (CONFIG_SYS_BOOT_FLASH_WIDTH, (vu_long *) base,
				&flash_info[0]);

	printf ("[%ldkB@%lx] ", size_b0 / 1024, base);

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

	base = memoryGetDeviceBaseAddress (CONFIG_SYS_EXTRA_FLASH_DEVICE);
/*	base = memoryGetDeviceBaseAddress(DEV_CS3_BASE_ADDR);*/
	for (i = 1; i < CONFIG_SYS_MAX_FLASH_BANKS; i++) {
		unsigned long size =
			flash_get_size (CONFIG_SYS_EXTRA_FLASH_WIDTH,
					(vu_long *) base, &flash_info[i]);

		printf ("[%ldMB@%lx] ", size >> 20, base);

		if (flash_info[i].flash_id == FLASH_UNKNOWN) {
			if (i == 1) {
				printf ("## Unknown FLASH at %08lx: Size = 0x%08lx = %ld MB\n", base, size_b1, size_b1 << 20);
			}
			break;
		}
		size_b1 += size;
		base += size;
	}

	flash_size = size_b0 + size_b1;
	return flash_size;
}

/*-----------------------------------------------------------------------
 */
static void flash_get_offsets (ulong base, flash_info_t * info)
{
	int i;
	int sector_size;

	if (!info->sector_count)
		return;

	/* set up sector start address table */
	switch (info->flash_id & FLASH_TYPEMASK) {
	case FLASH_AM040:
	case FLASH_28F128J3A:
	case FLASH_28F640J3A:
	case FLASH_RAM:
		/* this chip has uniformly spaced sectors */
		sector_size = info->size / info->sector_count;
		for (i = 0; i < info->sector_count; i++)
			info->start[i] = base + (i * sector_size);
		break;
	default:
		if (info->flash_id & FLASH_BTYPE) {
			/* set sector offsets for bottom boot block type    */
			info->start[0] = base + 0x00000000;
			info->start[1] = base + 0x00008000;
			info->start[2] = base + 0x0000C000;
			info->start[3] = base + 0x00010000;
			for (i = 4; i < info->sector_count; i++) {
				info->start[i] =
					base + (i * 0x00020000) - 0x00060000;
			}
		} else {
			/* set sector offsets for top boot block type               */
			i = info->sector_count - 1;
			info->start[i--] = base + info->size - 0x00008000;
			info->start[i--] = base + info->size - 0x0000C000;
			info->start[i--] = base + info->size - 0x00010000;
			for (; i >= 0; 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_STM:
		printf ("STM ");
		break;
	case FLASH_MAN_AMD:
		printf ("AMD ");
		break;
	case FLASH_MAN_FUJ:
		printf ("FUJITSU ");
		break;
	case FLASH_MAN_INTEL:
		printf ("INTEL ");
		break;
	default:
		printf ("Unknown Vendor ");
		break;
	}

	switch (info->flash_id & FLASH_TYPEMASK) {
	case FLASH_AM040:
		printf ("AM29LV040B (4 Mbit, bottom boot sect)\n");
		break;
	case FLASH_AM400B:
		printf ("AM29LV400B (4 Mbit, bottom boot sect)\n");
		break;
	case FLASH_AM400T:
		printf ("AM29LV400T (4 Mbit, top boot sector)\n");
		break;
	case FLASH_AM800B:
		printf ("AM29LV800B (8 Mbit, bottom boot sect)\n");
		break;
	case FLASH_AM800T:
		printf ("AM29LV800T (8 Mbit, top boot sector)\n");
		break;
	case FLASH_AM160B:
		printf ("AM29LV160B (16 Mbit, bottom boot sect)\n");
		break;
	case FLASH_AM160T:
		printf ("AM29LV160T (16 Mbit, top boot sector)\n");
		break;
	case FLASH_AM320B:
		printf ("AM29LV320B (32 Mbit, bottom boot sect)\n");
		break;
	case FLASH_AM320T:
		printf ("AM29LV320T (32 Mbit, top boot sector)\n");
		break;
	case FLASH_28F640J3A:
		printf ("28F640J3A (64 Mbit)\n");
		break;
	case FLASH_28F128J3A:
		printf ("28F128J3A (128 Mbit)\n");
		break;
	case FLASH_ROM:
		printf ("ROM\n");
		break;
	case FLASH_RAM:
		printf ("RAM\n");
		break;
	default:
		printf ("Unknown Chip Type\n");
		break;
	}

	if ((info->size >> 20) > 0) {
		printf ("  Size: %ld MB in %d Sectors\n",
			info->size >> 20, info->sector_count);
	} else {
		printf ("  Size: %ld kB in %d Sectors\n",
			info->size >> 10, 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 inline void flash_cmd (int width, volatile unsigned char *addr,
			      int offset, unsigned char cmd)
{
	/* supports 1x8, 1x16, and 2x16 */
	/* 2x8 and 4x8 are not supported */
	if (width == 4) {
		/* assuming chips are in 16 bit mode */
		/* 2x16 */
		unsigned long cmd32 = (cmd << 16) | cmd;

		*(volatile unsigned long *) (addr + offset * 2) = cmd32;
	} else {
		/* 1x16 or 1x8 */
		*(volatile unsigned char *) (addr + offset) = cmd;
	}
}

static ulong
flash_get_size (int portwidth, vu_long * addr, flash_info_t * info)
{
	short i;
	volatile unsigned char *caddr = (unsigned char *) addr;
	volatile unsigned short *saddr = (unsigned short *) addr;
	volatile unsigned long *laddr = (unsigned long *) addr;
	char old[2], save;
	ulong id = 0, manu = 0, base = (ulong) addr;

#ifdef DEBUG
	printf ("%s: enter\n", __FUNCTION__);
#endif
	info->portwidth = portwidth;

	save = *caddr;

	flash_cmd (portwidth, caddr, 0, 0xf0);
	flash_cmd (portwidth, caddr, 0, 0xf0);

	udelay (10);

	old[0] = caddr[0];
	old[1] = caddr[1];


	if (old[0] != 0xf0) {
		flash_cmd (portwidth, caddr, 0, 0xf0);
		flash_cmd (portwidth, caddr, 0, 0xf0);

		udelay (10);

		if (*caddr == 0xf0) {
			/* this area is ROM */
			*caddr = save;
			info->flash_id = FLASH_ROM + FLASH_MAN_UNKNOWN;
			info->sector_count = 8;
			info->size = 0x80000;
			flash_get_offsets (base, info);
			return info->size;
		}
	} else {
		*caddr = 0;

		udelay (10);

		if (*caddr == 0) {
			/* this area is RAM */
			*caddr = save;
			info->flash_id = FLASH_RAM + FLASH_MAN_UNKNOWN;
			info->sector_count = 8;
			info->size = 0x80000;
			flash_get_offsets (base, info);
			return info->size;
		}
		flash_cmd (portwidth, caddr, 0, 0xf0);

		udelay (10);
	}

	/* Write auto select command: read Manufacturer ID */
	flash_cmd (portwidth, caddr, 0x555, 0xAA);
	flash_cmd (portwidth, caddr, 0x2AA, 0x55);
	flash_cmd (portwidth, caddr, 0x555, 0x90);

	udelay (10);

	if ((caddr[0] == old[0]) && (caddr[1] == old[1])) {

		/* this area is ROM */
		info->flash_id = FLASH_ROM + FLASH_MAN_UNKNOWN;
		info->sector_count = 8;
		info->size = 0x80000;
		flash_get_offsets (base, info);
		return info->size;
#ifdef DEBUG
	} else {
		printf ("%px%d: %02x:%02x -> %02x:%02x\n",
			caddr, portwidth, old[0], old[1], caddr[0], caddr[1]);
#endif
	}

	switch (portwidth) {
	case 1:
		manu = caddr[0];
		manu |= manu << 16;
		id = caddr[1];
		break;
	case 2:
		manu = saddr[0];
		manu |= manu << 16;
		id = saddr[1];
		id |= id << 16;
		break;
	case 4:
		manu = laddr[0];
		id = laddr[1];
		break;
	}

#ifdef DEBUG
	flash_cmd (portwidth, caddr, 0, 0xf0);

	printf ("\n%08lx:%08lx:%08lx\n", base, manu, id);
	printf ("%08lx %08lx %08lx %08lx\n",
		laddr[0], laddr[1], laddr[2], laddr[3]);
#endif

	switch (manu) {
	case STM_MANUFACT:
		info->flash_id = FLASH_MAN_STM;
		break;
	case AMD_MANUFACT:
		info->flash_id = FLASH_MAN_AMD;
		break;
	case FUJ_MANUFACT:
		info->flash_id = FLASH_MAN_FUJ;
		break;
	case INTEL_MANUFACT:
		info->flash_id = FLASH_MAN_INTEL;
		break;
	default:
		flash_cmd (portwidth, caddr, 0, 0xf0);

		printf ("Unknown Mfr [%08lx]:%08lx\n", manu, id);
		info->flash_id = FLASH_UNKNOWN;
		info->sector_count = 0;
		info->size = 0;
		return (0);	/* no or unknown flash  */
	}

	switch (id) {
	case AMD_ID_LV400T:
		info->flash_id += FLASH_AM400T;
		info->sector_count = 11;
		info->size = 0x00100000;
		info->chipwidth = 1;
		break;		/* => 1 MB      */

	case AMD_ID_LV400B:
		info->flash_id += FLASH_AM400B;
		info->sector_count = 11;
		info->size = 0x00100000;
		info->chipwidth = 1;
		break;		/* => 1 MB      */

	case AMD_ID_LV800T:
		info->flash_id += FLASH_AM800T;
		info->sector_count = 19;
		info->size = 0x00200000;
		info->chipwidth = 1;
		break;		/* => 2 MB      */

	case AMD_ID_LV800B:
		info->flash_id += FLASH_AM800B;
		info->sector_count = 19;
		info->size = 0x00200000;
		info->chipwidth = 1;
		break;		/* => 2 MB      */

	case AMD_ID_LV160T:
		info->flash_id += FLASH_AM160T;
		info->sector_count = 35;
		info->size = 0x00400000;
		info->chipwidth = 1;
		break;		/* => 4 MB      */

	case AMD_ID_LV160B:
		info->flash_id += FLASH_AM160B;
		info->sector_count = 35;
		info->size = 0x00400000;
		info->chipwidth = 1;
		break;		/* => 4 MB      */
#if 0				/* enable when device IDs are available */
	case AMD_ID_LV320T:
		info->flash_id += FLASH_AM320T;
		info->sector_count = 67;
		info->size = 0x00800000;
		break;		/* => 8 MB      */

	case AMD_ID_LV320B:
		info->flash_id += FLASH_AM320B;
		info->sector_count = 67;
		info->size = 0x00800000;
		break;		/* => 8 MB      */
#endif
	case AMD_ID_LV040B:
		info->flash_id += FLASH_AM040;
		info->sector_count = 8;
		info->size = 0x80000;
		info->chipwidth = 1;
		break;		/* => 512 kB    */

	case INTEL_ID_28F640J3A:
		info->flash_id += FLASH_28F640J3A;
		info->sector_count = 64;
		info->size = 128 * 1024 * 64;	/* 128kbytes x 64 blocks */
		info->chipwidth = 2;
		if (portwidth == 4)
			info->size *= 2;	/* 2x16 */
		break;

	case INTEL_ID_28F128J3A:
		info->flash_id += FLASH_28F128J3A;
		info->sector_count = 128;
		info->size = 128 * 1024 * 128;	/* 128kbytes x 128 blocks */
		info->chipwidth = 2;
		if (portwidth == 4)
			info->size *= 2;	/* 2x16 */
		break;

	default:
		flash_cmd (portwidth, caddr, 0, 0xf0);

		printf ("Unknown id %lx:[%lx]\n", manu, id);
		info->flash_id = FLASH_UNKNOWN;
		info->chipwidth = 1;
		return (0);	/* => no or unknown flash */

	}

	flash_get_offsets (base, info);


	/* check for protected sectors */
	for (i = 0; i < info->sector_count; i++) {
		/* read sector protection at sector address, (A7 .. A0)=0x02 */
		/* D0 = 1 if protected */
		caddr = (volatile unsigned char *) (info->start[i]);
		saddr = (volatile unsigned short *) (info->start[i]);
		laddr = (volatile unsigned long *) (info->start[i]);
		if (portwidth == 1)
			info->protect[i] = caddr[2] & 1;
		else if (portwidth == 2)
			info->protect[i] = saddr[2] & 1;
		else
			info->protect[i] = laddr[2] & 1;
	}

	/*
	 * Prevent writes to uninitialized FLASH.
	 */
	if (info->flash_id != FLASH_UNKNOWN) {
		caddr = (volatile unsigned char *) info->start[0];

		flash_cmd (portwidth, caddr, 0, 0xF0);	/* reset bank */
	}

	return (info->size);
}

int flash_erase (flash_info_t * info, int s_first, int s_last)
{
	volatile unsigned char *addr = (uchar *) (info->start[0]);
	int flag, prot, sect, l_sect;
	ulong start, now, last;

/* modified to support 2x16 Intel flash */
/* Note that the code will not exit on a flash erasure error or timeout */
/* but will print and error message and continue processing sectors */
/* until they are all erased. */
/* 10-16-2002 P. Marchese */
	ulong mask;
	int timeout;

	if (info->portwidth == 4)
/*		{
		printf ("- Warning: erasing of 32Bit (2*16Bit i.e. 2*28F640J3A) not supported yet !!!! \n");
		return 1;
		}*/
	{
		/* make sure it's Intel flash */
		if ((info->flash_id & FLASH_VENDMASK) == FLASH_MAN_INTEL) {
			/* yup! it's an Intel flash */
			/* is it 16-bits wide? */
			if (info->chipwidth == 2) {
				/* yup! it's 16-bits wide */
				/* are there any sectors to process? */
				if ((s_first < 0) || (s_first > s_last)) {
					printf ("Error:  There are no sectors to erase\n");
					printf ("Either sector %d is less than zero\n", s_first);
					printf ("or sector %d is greater than sector %d\n", s_first, s_last);
					return 1;
				}
				/* check for protected sectors */
				prot = 0;
				for (sect = s_first; sect <= s_last; ++sect)
					if (info->protect[sect])
						prot++;
				/* if variable "prot" is nonzero, there are protected sectors */
				if (prot)
					printf ("- Warning: %d protected sectors will not be erased!\n", prot);
				/* reset the flash */
				flash_cmd (info->portwidth, addr, 0,
					   CHIP_CMD_RST);
				/* Disable interrupts which might cause a timeout here */
				flag = disable_interrupts ();
				/* Clear the status register */
				flash_cmd (info->portwidth, addr, 0,
					   CHIP_CMD_CLR_STAT);
				flash_cmd (info->portwidth, addr, 0,
					   CHIP_CMD_RST);
				/* Start erase on unprotected sectors */
				for (sect = s_first; sect <= s_last; sect++) {
					/* is the sector unprotected? */
					if (info->protect[sect] == 0) {	/* not protected */
						/* issue the single block erase command, 0x20 */
						flash_cmd (info->portwidth,
							   (volatile unsigned
							    char *) info->
							   start[sect], 0,
							   CHIP_CMD_ERASE1);
						/* issue the erase confirm command, 0xD0 */
						flash_cmd (info->portwidth,
							   (volatile unsigned
							    char *) info->
							   start[sect], 0,
							   CHIP_CMD_ERASE2);
						l_sect = sect;
						/* re-enable interrupts if necessary */
						if (flag)
							enable_interrupts ();
						/* poll for erasure completion */
						/* put flash into read status mode by writing 0x70 to it */
						flash_cmd (info->portwidth,
							   addr, 0,
							   CHIP_CMD_RD_STAT);
						/* setup the status register mask */
						mask = CHIP_STAT_RDY |
							(CHIP_STAT_RDY << 16);
						/* init. the timeout counter */
						start = get_timer (0);
						/* keep looping while the flash is not ready */
						/* exit the loop by timing out or the flash */
						/* becomes ready again */
						timeout = 0;
						while ((*
							(volatile unsigned
							 long *) info->
							start[sect] & mask) !=
						       mask) {
							/* has the timeout limit been reached? */
							if (get_timer (start)
							    >
							    CONFIG_SYS_FLASH_ERASE_TOUT)
							{
								/* timeout limit reached */
								printf ("Time out limit reached erasing sector at address %08lx\n", info->start[sect]);
								printf ("Continuing with next sector\n");
								timeout = 1;
								goto timed_out_error;
							}
							/* put flash into read status mode by writing 0x70 to it */
							flash_cmd (info->
								   portwidth,
								   addr, 0,
								   CHIP_CMD_RD_STAT);
						}
						/* did we timeout? */
					      timed_out_error:if (timeout == 0)
						{
							/* didn't timeout, so check the status register */
							/* create the status mask to check for errors */
							mask = CHIP_STAT_ECLBS;
							mask = mask | (mask <<
								       16);
							/* put flash into read status mode by writing 0x70 to it */
							flash_cmd (info->
								   portwidth,
								   addr, 0,
								   CHIP_CMD_RD_STAT);
							/* are there any errors? */
							if ((*
							     (volatile
							      unsigned long *)
							     info->
							     start[sect] &
							     mask) != 0) {
								/* We got an erasure error */
								printf ("Flash erasure error at address 0x%08lx\n", info->start[sect]);
								printf ("Continuing with next sector\n");
								/* reset the flash */
								flash_cmd
									(info->
									 portwidth,
									 addr,
									 0,
									 CHIP_CMD_RST);
							}
						}
						/* erasure completed without errors */
						/* reset the flash */
						flash_cmd (info->portwidth,
							   addr, 0,
							   CHIP_CMD_RST);
					}	/* end if not protected */
				}	/* end for loop */
				printf ("Flash erasure done\n");
				return 0;
			} else {
				/* The Intel flash is not 16-bit wide */
				/* print and error message and return */
				/* NOTE: you can add routines here to handle other size flash */
				printf ("Error: Intel flash device is only %d-bits wide\n", info->chipwidth * 8);
				printf ("The erasure code only handles Intel 16-bit wide flash memory\n");
				return 1;
			}
		} else {
			/* Not Intel flash so return an error as a write timeout */
			/* NOTE: if it's another type flash, stick its routine here */
			printf ("Error: The flash device is not Intel type\n");
			printf ("The erasure code only supports Intel flash in a 32-bit port width\n");
			return 1;
		}
	}

	/* end 32-bit wide flash code */
	if ((info->flash_id & FLASH_TYPEMASK) == FLASH_ROM)
		return 1;	/* Rom can not be erased */
	if ((info->flash_id & FLASH_TYPEMASK) == FLASH_RAM) {	/* RAM just copy 0s to RAM */
		for (sect = s_first; sect <= s_last; sect++) {
			int sector_size = info->size / info->sector_count;

			addr = (uchar *) (info->start[sect]);
			memset ((void *) addr, 0, sector_size);
		}
		return 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;
	}

	if ((info->flash_id & FLASH_VENDMASK) == FLASH_MAN_INTEL) {	/* Intel works spezial */
		return flash_erase_intel (info,
					  (unsigned short) s_first,
					  (unsigned short) s_last);
	}
#if 0
	if ((info->flash_id == FLASH_UNKNOWN) ||	/* Flash is unknown to PPCBoot */
	    (info->flash_id > FLASH_AMD_COMP)) {
		printf ("Can't erase unknown flash type %08lx - aborted\n",
			info->flash_id);
		return 1;
	}
#endif

	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");
	}

	l_sect = -1;

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

	flash_cmd (info->portwidth, addr, 0x555, 0xAA);	/* start erase routine */
	flash_cmd (info->portwidth, addr, 0x2AA, 0x55);
	flash_cmd (info->portwidth, addr, 0x555, 0x80);
	flash_cmd (info->portwidth, addr, 0x555, 0xAA);
	flash_cmd (info->portwidth, addr, 0x2AA, 0x55);

	/* Start erase on unprotected sectors */
	for (sect = s_first; sect <= s_last; sect++) {
		if (info->protect[sect] == 0) {	/* not protected */
			addr = (uchar *) (info->start[sect]);
			flash_cmd (info->portwidth, addr, 0, 0x30);
			l_sect = sect;
		}
	}

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

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

	/*
	 * We wait for the last triggered sector
	 */
	if (l_sect < 0)
		goto DONE;

	start = get_timer (0);
	last = start;
	addr = (volatile unsigned char *) (info->start[l_sect]);
	/* broken for 2x16: TODO */
	while ((addr[0] & 0x80) != 0x80) {
		if ((now = get_timer (start)) > CONFIG_SYS_FLASH_ERASE_TOUT) {
			printf ("Timeout\n");
			return 1;
		}
		/* show that we're waiting */
		if ((now - last) > 1000) {	/* every second */
			putc ('.');
			last = now;
		}
	}

      DONE:
	/* reset to read mode */
	addr = (volatile unsigned char *) info->start[0];
	flash_cmd (info->portwidth, addr, 0, 0xf0);
	flash_cmd (info->portwidth, addr, 0, 0xf0);

	printf (" done\n");
	return 0;
}

/*-----------------------------------------------------------------------
 * Copy memory to flash, returns:
 * 0 - OK
 * 1 - write timeout
 * 2 - Flash not erased
 */

/* broken for 2x16: TODO */
int write_buff (flash_info_t * info, uchar * src, ulong addr, ulong cnt)
{
	ulong cp, wp, data;
	int i, l, rc;

/* Commented out since the below code should work for 32-bit(2x 16 flash) */
/* 10-16-2002 P. Marchese */
/*	if(info->portwidth==4) return 1; */
/*	if(info->portwidth==4) {
		printf ("- Warning: writting of 32Bit (2*16Bit i.e. 2*28F640J3A) not supported yet !!!! \n");
		return 1;
		}*/

	if ((info->flash_id & FLASH_TYPEMASK) == FLASH_ROM)
		return 0;
	if ((info->flash_id & FLASH_TYPEMASK) == FLASH_RAM) {
		memcpy ((void *) addr, src, cnt);
		return 0;
	}

	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);
		}
		for (; i < 4 && cnt > 0; ++i) {
			data = (data << 8) | *src++;
			--cnt;
			++cp;
		}
		for (; cnt == 0 && i < 4; ++i, ++cp) {
			data = (data << 8) | (*(uchar *) cp);
		}

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

	/*
	 * handle word aligned part
	 */
	while (cnt >= 4) {
		data = 0;
		for (i = 0; i < 4; ++i) {
			data = (data << 8) | *src++;
		}
		if ((rc = write_word (info, wp, data)) != 0) {
			return (rc);
		}
		wp += 4;
		cnt -= 4;
	}

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

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

	return (write_word (info, wp, data));
}

/*-----------------------------------------------------------------------
 * Write a word to Flash, returns:
 * 0 - OK
 * 1 - write timeout
 * 2 - Flash not erased
 */
/* broken for 2x16: TODO */
static int write_word (flash_info_t * info, ulong dest, ulong data)
{
	volatile unsigned char *addr = (uchar *) (info->start[0]);
	ulong start;
	int flag, i;
	ulong mask;

/* modified so that it handles 32-bit(2x16 Intel flash programming */
/* 10-16-2002 P. Marchese */

	if (info->portwidth == 4)
/*		{
		printf ("- Warning: writting of 32Bit (2*16Bit i.e. 2*28F640J3A) not supported yet !!!! \n");
		return 1;
		}*/
	{
		/* make sure it's Intel flash */
		if ((info->flash_id & FLASH_VENDMASK) == FLASH_MAN_INTEL) {
			/* yup! it's an Intel flash */
			/* is it 16-bits wide? */
			if (info->chipwidth == 2) {
				/* yup! it's 16-bits wide */
				/* so we know how to program it */
				/* reset the flash */
				flash_cmd (info->portwidth, addr, 0,
					   CHIP_CMD_RST);
				/* Disable interrupts which might cause a timeout here */
				flag = disable_interrupts ();
				/* Clear the status register */
				flash_cmd (info->portwidth, addr, 0,
					   CHIP_CMD_CLR_STAT);
				flash_cmd (info->portwidth, addr, 0,
					   CHIP_CMD_RST);
				/* 1st cycle of word/byte program */
				/* write 0x40 to the location to program */
				flash_cmd (info->portwidth, (uchar *) dest, 0,
					   CHIP_CMD_PROG);
				/* 2nd cycle of word/byte program */
				/* write the data to the destination address */
				*(ulong *) dest = data;
				/* re-enable interrupts if necessary */
				if (flag)
					enable_interrupts ();
				/* setup the status register mask */
				mask = CHIP_STAT_RDY | (CHIP_STAT_RDY << 16);
				/* put flash into read status mode by writing 0x70 to it */
				flash_cmd (info->portwidth, addr, 0,
					   CHIP_CMD_RD_STAT);
				/* init. the timeout counter */
				start = get_timer (0);
				/* keep looping while the flash is not ready */
				/* exit the loop by timing out or the flash */
				/* becomes ready again */
/* 11-13-2002 Paul Marchese */
/* modified while loop conditional statement */
/* because we were always timing out.  */
/* there is a type mismatch, "addr[0]" */
/* returns a byte but "mask" is a 32-bit value */
				while ((*(volatile unsigned long *) info->
					start[0] & mask) != mask)
/* original code */
/* while (addr[0] & mask) != mask) */
				{
					/* has the timeout limit been reached? */
					if (get_timer (start) >
					    CONFIG_SYS_FLASH_WRITE_TOUT) {
						/* timeout limit reached */
						printf ("Time out limit reached programming address %08lx with data %08lx\n", dest, data);
						/* reset the flash */
						flash_cmd (info->portwidth,
							   addr, 0,
							   CHIP_CMD_RST);
						return (1);
					}
					/* put flash into read status mode by writing 0x70 to it */
					flash_cmd (info->portwidth, addr, 0,
						   CHIP_CMD_RD_STAT);
				}
				/* flash is ready, so check the status */
				/* create the status mask to check for errors */
				mask = CHIP_STAT_DPS | CHIP_STAT_VPPS |
					CHIP_STAT_PSLBS;
				mask = mask | (mask << 16);
				/* put flash into read status mode by writing 0x70 to it */
				flash_cmd (info->portwidth, addr, 0,
					   CHIP_CMD_RD_STAT);
				/* are there any errors? */
				if ((addr[0] & mask) != 0) {
					/* We got a one of the following errors: */
					/* Voltage range, Device protect, or programming */
					/* return the error as a device timeout */
					/* put flash into read status mode by writing 0x70 to it */
					flash_cmd (info->portwidth, addr, 0,
						   CHIP_CMD_RD_STAT);
					printf ("Flash programming error at address 0x%08lx\n", dest);
					printf ("Flash status register contains 0x%08lx\n", (unsigned long) addr[0]);
					/* reset the flash */
					flash_cmd (info->portwidth, addr, 0,
						   CHIP_CMD_RST);
					return 1;
				}
				/* write completed without errors */
				/* reset the flash */
				flash_cmd (info->portwidth, addr, 0,
					   CHIP_CMD_RST);
				return 0;
			} else {
				/* it's not 16-bits wide, so return an error as a write timeout */
				/* NOTE: you can add routines here to handle other size flash */
				printf ("Error: Intel flash device is only %d-bits wide\n", info->chipwidth * 8);
				printf ("The write code only handles Intel 16-bit wide flash memory\n");
				return 1;
			}
		} else {
			/* not Intel flash so return an error as a write timeout */
			/* NOTE: if it's another type flash, stick its routine here */
			printf ("Error: The flash device is not Intel type\n");
			printf ("The code only supports Intel flash in a 32-bit port width\n");
			return 1;
		}
	}

	/* end of 32-bit flash code */
	if ((info->flash_id & FLASH_TYPEMASK) == FLASH_ROM)
		return 1;
	if ((info->flash_id & FLASH_TYPEMASK) == FLASH_RAM) {
		*(unsigned long *) dest = data;
		return 0;
	}
	if ((info->flash_id & FLASH_VENDMASK) == FLASH_MAN_INTEL) {
		unsigned short low = data & 0xffff;
		unsigned short hi = (data >> 16) & 0xffff;
		int ret = write_word_intel ((bank_addr_t) dest, hi);

		if (!ret)
			ret = write_word_intel ((bank_addr_t) (dest + 2),
						low);

		return ret;
	}

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

	/* first, perform an unlock bypass command to speed up flash writes */
	addr[0x555] = 0xAA;
	addr[0x2AA] = 0x55;
	addr[0x555] = 0x20;

	/* write each byte out */
	for (i = 0; i < 4; i++) {
		char *data_ch = (char *) &data;

		addr[0] = 0xA0;
		*(((char *) dest) + i) = data_ch[i];
		udelay (10);	/* XXX */
	}

	/* we're done, now do an unlock bypass reset */
	addr[0] = 0x90;
	addr[0] = 0x00;

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

	/* data polling for D7 */
	start = get_timer (0);
	while ((*((vu_long *) dest) & 0x00800080) != (data & 0x00800080)) {
		if (get_timer (start) > CONFIG_SYS_FLASH_WRITE_TOUT) {
			return (1);
		}
	}
	return (0);
}