flash.c

AT91RM9200的完整启动代码：包括loader, boot及U-boot三部分均已编译通过！欢迎下载使用！

/*
 * (C)  Copyright 2001
 * St鋟bli Faverges - <www.staubli.com>
 * Pierre AUBERT  [e-mail]
 * U-Boot port on RPXClassic LF (CLLF_BW31) board
 *
 * RPXClassic uses Am29DL323B flash memory with 2 banks
 *
 *
 * (C) Copyright 2000
 * Wolfgang Denk, DENX Software Engineering, [e-mail].
 *
 * 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	*/

/*-----------------------------------------------------------------------
 * Functions
 */
static ulong flash_get_size (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 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;
	}

	size_b0 = flash_get_size((vu_long *)CFG_FLASH_BASE, &flash_info[0]);


        flash_get_offsets (CFG_FLASH_BASE, &flash_info[0]);

#if CFG_MONITOR_BASE >= CFG_FLASH_BASE
	/* monitor protection ON by default */
	flash_protect(FLAG_PROTECT_SET,
		      CFG_MONITOR_BASE,
		      CFG_MONITOR_BASE+monitor_flash_len-1,
		      &flash_info[0]);
#endif

	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_BTYPE) {
		/* set sector offsets for bottom boot block type	*/
		info->start[0] = base + 0x00000000;
		info->start[1] = base + 0x00008000;
		info->start[2] = base + 0x00010000;
		info->start[3] = base + 0x00018000;
		info->start[4] = base + 0x00020000;
		info->start[5] = base + 0x00028000;
		info->start[6] = base + 0x00030000;
		info->start[7] = base + 0x00038000;
		for (i = 8; i < info->sector_count; i++) {
			info->start[i] = base + ((i-7) * 0x00040000) ;
		}
	}
}

/*-----------------------------------------------------------------------
 */
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_AMD:	printf ("AMD ");		break;
	default:		printf ("Unknown Vendor ");	break;
	}

	switch (info->flash_id & FLASH_TYPEMASK) {
        case FLASH_AMDL323B:
            printf ("AMDL323DB (16 Mbytes, bottom boot sect)\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");
}

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


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

/*
 * The following code cannot be run from FLASH!
 */

static ulong flash_get_size (vu_long *addr, flash_info_t *info)
{
	short i;
	ulong value;
	ulong base = (ulong)addr;

        /* Reset flash componeny                                             */
        addr [0] = 0xf0f0f0f0;

        /* Write auto select command: read Manufacturer ID */
        addr[0xAAA] = 0xAAAAAAAA ;
	addr[0x555] = 0x55555555 ;
	addr[0xAAA] = 0x90909090 ;

	value = addr[0] ;

	switch (value & 0x00FF00FF) {
	case AMD_MANUFACT:
		info->flash_id = FLASH_MAN_AMD;
		break;
	default:
		info->flash_id = FLASH_UNKNOWN;
		info->sector_count = 0;
		info->size = 0;
		return (0);			/* no or unknown flash	*/
	}

	value = addr[2] ;		/* device ID		*/

	switch (value & 0x00FF00FF) {
        case (AMD_ID_DL323B & 0x00FF00FF):
            info->flash_id += FLASH_AMDL323B;
            info->sector_count = 71;
            info->size = 0x01000000;            /* 16 Mb                     */

            break;
	default:
		info->flash_id = FLASH_UNKNOWN;
		return (0);			/* => no or unknown flash */

	}
	/* set up sector start address table */
        /* set sector offsets for bottom boot block type	*/
        info->start[0] = base + 0x00000000;
        info->start[1] = base + 0x00008000;
        info->start[2] = base + 0x00010000;
        info->start[3] = base + 0x00018000;
        info->start[4] = base + 0x00020000;
        info->start[5] = base + 0x00028000;
        info->start[6] = base + 0x00030000;
        info->start[7] = base + 0x00038000;
        for (i = 8; i < info->sector_count; i++) {
            info->start[i] = base + ((i-7) * 0x00040000) ;
        }

	/* check for protected sectors */
        for (i = 0; i < 23; i++) {
            /* read sector protection at sector address, (A7 .. A0) = 0x02 */
            /* D0 = 1 if protected */
            addr = (volatile unsigned long *)(info->start[i]);
            info->protect[i] = addr[4] & 1 ;
	}
        /* Check for protected sectors in the 2nd bank                       */
        addr[0x100AAA] = 0xAAAAAAAA ;
        addr[0x100555] = 0x55555555 ;
        addr[0x100AAA] = 0x90909090 ;

        for (i = 23; i < info->sector_count; i++) {
            /* read sector protection at sector address, (A7 .. A0) = 0x02 */
            /* D0 = 1 if protected */
            addr = (volatile unsigned long *)(info->start[i]);
            info->protect[i] = addr[4] & 1 ;
	}

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

		*addr = 0xF0F0F0F0;	/* reset bank 1                      */
		addr = (volatile unsigned long *)info->start[23];

		*addr = 0xF0F0F0F0;	/* reset bank 2                      */

	}

	return (info->size);
}


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

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

	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_UNKNOWN) ||
	    (info->flash_id > FLASH_AMD_COMP)) {
		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");
	}

	l_sect = -1;

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

	addr[0xAAA] = 0xAAAAAAAA;
	addr[0x555] = 0x55555555;
	addr[0xAAA] = 0x80808080;
	addr[0xAAA] = 0xAAAAAAAA;
	addr[0x555] = 0x55555555;

	/* Start erase on unprotected sectors */
	for (sect = s_first; sect<=s_last; sect++) {
		if (info->protect[sect] == 0) {	/* not protected */
			addr = (vu_long *)(info->start[sect]) ;
			addr[0] = 0x30303030 ;
			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 = (vu_long *)(info->start[l_sect]);
	while ((addr[0] & 0x80808080) != 0x80808080) {
		if ((now = get_timer(start)) > CFG_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 = (vu_long *)info->start[0];
	addr[0] = 0xF0F0F0F0;	/* reset bank */

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

/*-----------------------------------------------------------------------
 * 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 cp, wp, data;
	int i, l, 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);
		}
		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
 */
static int write_word (flash_info_t *info, ulong dest, ulong data)
{
	vu_long *addr = (vu_long *)(info->start[0]);
	ulong start;
	int flag;

	/* 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();

	addr[0xAAA] = 0xAAAAAAAA;
	addr[0x555] = 0x55555555;
	addr[0xAAA] = 0xA0A0A0A0;

	*((vu_long *)dest) = data;

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

	/* data polling for D7 */
	start = get_timer (0);
	while ((*((vu_long *)dest) & 0x80808080) != (data & 0x80808080)) {
		if (get_timer(start) > CFG_FLASH_WRITE_TOUT) {
			return (1);
		}
	}
	return (0);
}

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