nand_base.c

嵌入式试验箱S3C2410的bootloader源代码

#ifdef CONFIG_SURPORT_WINCE
#if 0
        char oob_buf[16];
        SectorInfo *psi = (SectorInfo *)oob_buf;
        int i;
		this->cmdfunc (mtd, NAND_CMD_READOOB, 0, page & this->pagemask);
        this->read_buf(mtd, oob_buf, 16);

        if (psi->bOEMReserved == (OEM_BLOCK_RESERVED | OEM_BLOCK_READONLY) &&
            psi->bBadBlock == BADBLOCKMARK)
            res = 0;
        else if (psi->bBadBlock != 0xff)
    		res = 1;
#endif
        //printf("bad? ofs = 0x%x, RESERVED_BOOT_BLOCKS = 0x%x,  mtd->erasesize = 0x%x, mul = 0x%x\n", ofs, RESERVED_BOOT_BLOCKS, mtd->erasesize, RESERVED_BOOT_BLOCKS*mtd->erasesize);
        if (ofs < RESERVED_BOOT_BLOCKS * mtd->erasesize)
            res = 0;
        else
#endif        
        {
    		this->cmdfunc (mtd, NAND_CMD_READOOB, this->badblockpos, page & this->pagemask);
    		if (this->read_byte(mtd) != 0xff)
    			res = 1;
        }

        // Apply delay or wait for ready/busy pin
        // add by www.arm9.net, if not, the erase will be failed
		if (!this->dev_ready)
			udelay (this->chip_delay);
		else
			while (!this->dev_ready(mtd));

	}

	if (getchip) {
		/* Deselect and wake up anyone waiting on the device */
		nand_release_device(mtd);
	}

	return res;
}

/**
 * nand_default_block_markbad - [DEFAULT] mark a block bad
 * @mtd:	MTD device structure
 * @ofs:	offset from device start
 *
 * This is the default implementation, which can be overridden by
 * a hardware specific driver.
*/
static int nand_default_block_markbad(struct mtd_info *mtd, loff_t ofs)
{
	struct nand_chip *this = mtd->priv;
	u_char buf[2] = {0, 0};
	size_t	retlen;
	int block;

	/* Get block number */
	block = ((int) ofs) >> this->bbt_erase_shift;
	this->bbt[block >> 2] |= 0x01 << ((block & 0x03) << 1);

	/* Do we have a flash based bad block table ? */
	if (this->options & NAND_USE_FLASH_BBT)
		return nand_update_bbt (mtd, ofs);

	/* We write two bytes, so we dont have to mess with 16 bit access */
	ofs += mtd->oobsize + (this->badblockpos & ~0x01);
	return nand_write_oob (mtd, ofs , 2, &retlen, buf);
}

/**
 * nand_check_wp - [GENERIC] check if the chip is write protected
 * @mtd:	MTD device structure
 * Check, if the device is write protected
 *
 * The function expects, that the device is already selected
 */
static int nand_check_wp (struct mtd_info *mtd)
{
	struct nand_chip *this = mtd->priv;
	/* Check the WP bit */
	this->cmdfunc (mtd, NAND_CMD_STATUS, -1, -1);
	return (this->read_byte(mtd) & 0x80) ? 0 : 1;
}

/**
 * nand_block_checkbad - [GENERIC] Check if a block is marked bad
 * @mtd:	MTD device structure
 * @ofs:	offset from device start
 * @getchip:	0, if the chip is already selected
 * @allowbbt:	1, if its allowed to access the bbt area
 *
 * Check, if the block is bad. Either by reading the bad block table or
 * calling of the scan function.
 */
static int nand_block_checkbad (struct mtd_info *mtd, loff_t ofs, int getchip, int allowbbt)
{
	struct nand_chip *this = mtd->priv;

//	if (!this->bbt)
		return this->block_bad(mtd, ofs, getchip);

	/* Return info from the table */
//	return nand_isbad_bbt (mtd, ofs, allowbbt);
}

/**
 * nand_command - [DEFAULT] Send command to NAND device
 * @mtd:	MTD device structure
 * @command:	the command to be sent
 * @column:	the column address for this command, -1 if none
 * @page_addr:	the page address for this command, -1 if none
 *
 * Send command to NAND device. This function is used for small page
 * devices (256/512 Bytes per page)
 */
static void nand_command (struct mtd_info *mtd, unsigned command, int column, int page_addr)
{
	register struct nand_chip *this = mtd->priv;

	/* Begin command latch cycle */
	this->hwcontrol(mtd, NAND_CTL_SETCLE);
	/*
	 * Write out the command to the device.
	 */
	if (command == NAND_CMD_SEQIN) {
		int readcmd;

		if (column >= mtd->oobblock) {
			/* OOB area */
			column -= mtd->oobblock;
			readcmd = NAND_CMD_READOOB;
		} else if (column < 256) {
			/* First 256 bytes --> READ0 */
			readcmd = NAND_CMD_READ0;
		} else {
			column -= 256;
			readcmd = NAND_CMD_READ1;
		}
		this->write_byte(mtd, readcmd);
	}
	this->write_byte(mtd, command);

	/* Set ALE and clear CLE to start address cycle */
	this->hwcontrol(mtd, NAND_CTL_CLRCLE);

	if (column != -1 || page_addr != -1) {
		this->hwcontrol(mtd, NAND_CTL_SETALE);

		/* Serially input address */
		if (column != -1) {
			/* Adjust columns for 16 bit buswidth */
			if (this->options & NAND_BUSWIDTH_16)
				column >>= 1;
			this->write_byte(mtd, column);
		}
		if (page_addr != -1) {
			this->write_byte(mtd, (unsigned char) (page_addr & 0xff));
			this->write_byte(mtd, (unsigned char) ((page_addr >> 8) & 0xff));
			/* One more address cycle for devices > 32MiB */
			if (this->chipsize > (32 << 20))
				this->write_byte(mtd, (unsigned char) ((page_addr >> 16) & 0x0f));
		}
		/* Latch in address */
		this->hwcontrol(mtd, NAND_CTL_CLRALE);
	}

	/*
	 * program and erase have their own busy handlers
	 * status and sequential in needs no delay
	*/
	switch (command) {

	case NAND_CMD_PAGEPROG:
	case NAND_CMD_ERASE1:
	case NAND_CMD_ERASE2:
	case NAND_CMD_SEQIN:
	case NAND_CMD_STATUS:
		return;

	case NAND_CMD_RESET:
		if (this->dev_ready)
			break;
		udelay(this->chip_delay);
		this->hwcontrol(mtd, NAND_CTL_SETCLE);
		this->write_byte(mtd, NAND_CMD_STATUS);
		this->hwcontrol(mtd, NAND_CTL_CLRCLE);
		while ( !(this->read_byte(mtd) & 0x40));
		return;

	/* This applies to read commands */
	default:
		/*
		 * If we don't have access to the busy pin, we apply the given
		 * command delay
		*/
		if (!this->dev_ready) {
			udelay (this->chip_delay);
			return;
		}
	}

	/* Apply this short delay always to ensure that we do wait tWB in
	 * any case on any machine. */
	ndelay (100);
	/* wait until command is processed */
	while (!this->dev_ready(mtd));
}

/**
 * nand_command_lp - [DEFAULT] Send command to NAND large page device
 * @mtd:	MTD device structure
 * @command:	the command to be sent
 * @column:	the column address for this command, -1 if none
 * @page_addr:	the page address for this command, -1 if none
 *
 * Send command to NAND device. This is the version for the new large page devices
 * We dont have the seperate regions as we have in the small page devices.
 * We must emulate NAND_CMD_READOOB to keep the code compatible.
 *
 */
static void nand_command_lp (struct mtd_info *mtd, unsigned command, int column, int page_addr)
{
	register struct nand_chip *this = mtd->priv;

	/* Emulate NAND_CMD_READOOB */
	if (command == NAND_CMD_READOOB) {
		column += mtd->oobblock;
		command = NAND_CMD_READ0;
	}


	/* Begin command latch cycle */
	this->hwcontrol(mtd, NAND_CTL_SETCLE);
	/* Write out the command to the device. */
	this->write_byte(mtd, command);
	/* End command latch cycle */
	this->hwcontrol(mtd, NAND_CTL_CLRCLE);

	if (column != -1 || page_addr != -1) {
		this->hwcontrol(mtd, NAND_CTL_SETALE);

		/* Serially input address */
		if (column != -1) {
			/* Adjust columns for 16 bit buswidth */
			if (this->options & NAND_BUSWIDTH_16)
				column >>= 1;
			this->write_byte(mtd, column & 0xff);
			this->write_byte(mtd, column >> 8);
		}
		if (page_addr != -1) {
			this->write_byte(mtd, (unsigned char) (page_addr & 0xff));
			this->write_byte(mtd, (unsigned char) ((page_addr >> 8) & 0xff));
			/* One more address cycle for devices > 128MiB */
			if (this->chipsize > (128 << 20))
				this->write_byte(mtd, (unsigned char) ((page_addr >> 16) & 0xff));
		}
		/* Latch in address */
		this->hwcontrol(mtd, NAND_CTL_CLRALE);
	}

	/*
	 * program and erase have their own busy handlers
	 * status and sequential in needs no delay
	*/
	switch (command) {

	case NAND_CMD_CACHEDPROG:
	case NAND_CMD_PAGEPROG:
	case NAND_CMD_ERASE1:
	case NAND_CMD_ERASE2:
	case NAND_CMD_SEQIN:
	case NAND_CMD_STATUS:
		return;


	case NAND_CMD_RESET:
		if (this->dev_ready)
			break;
		udelay(this->chip_delay);
		this->hwcontrol(mtd, NAND_CTL_SETCLE);
		this->write_byte(mtd, NAND_CMD_STATUS);
		this->hwcontrol(mtd, NAND_CTL_CLRCLE);
		while ( !(this->read_byte(mtd) & 0x40));
		return;

	case NAND_CMD_READ0:
		/* Begin command latch cycle */
		this->hwcontrol(mtd, NAND_CTL_SETCLE);
		/* Write out the start read command */
		this->write_byte(mtd, NAND_CMD_READSTART);
		/* End command latch cycle */
		this->hwcontrol(mtd, NAND_CTL_CLRCLE);
		/* Fall through into ready check */

	/* This applies to read commands */
	default:
		/*
		 * If we don't have access to the busy pin, we apply the given
		 * command delay
		*/
		if (!this->dev_ready) {
			udelay (this->chip_delay);
			return;
		}
	}

	/* Apply this short delay always to ensure that we do wait tWB in
	 * any case on any machine. */
	ndelay (100);
	/* wait until command is processed */
	while (!this->dev_ready(mtd));
}

/**
 * nand_get_device - [GENERIC] Get chip for selected access
 * @this:	the nand chip descriptor
 * @mtd:	MTD device structure
 * @new_state:	the state which is requested
 *
 * Get the device and lock it for exclusive access
 */
/* XXX U-BOOT XXX */
#if 0
static void nand_get_device (struct nand_chip *this, struct mtd_info *mtd, int new_state)
{
	struct nand_chip *active = this;

	DECLARE_WAITQUEUE (wait, current);

	/*
	 * Grab the lock and see if the device is available
	*/
retry:
	/* Hardware controller shared among independend devices */
	if (this->controller) {
		spin_lock (&this->controller->lock);
		if (this->controller->active)
			active = this->controller->active;
		else
			this->controller->active = this;
		spin_unlock (&this->controller->lock);
	}

	if (active == this) {
		spin_lock (&this->chip_lock);
		if (this->state == FL_READY) {
			this->state = new_state;
			spin_unlock (&this->chip_lock);
			return;
		}
	}
	set_current_state (TASK_UNINTERRUPTIBLE);
	add_wait_queue (&active->wq, &wait);
	spin_unlock (&active->chip_lock);
	schedule ();
	remove_wait_queue (&active->wq, &wait);
	goto retry;
}
#else
static void nand_get_device (struct nand_chip *this, struct mtd_info *mtd, int new_state) {}
#endif

/**
 * nand_wait - [DEFAULT]  wait until the command is done
 * @mtd:	MTD device structure
 * @this:	NAND chip structure
 * @state:	state to select the max. timeout value
 *
 * Wait for command done. This applies to erase and program only
 * Erase can take up to 400ms and program up to 20ms according to
 * general NAND and SmartMedia specs
 *
*/
/* XXX U-BOOT XXX */
#if 0
static int nand_wait(struct mtd_info *mtd, struct nand_chip *this, int state)
{
	unsigned long	timeo = jiffies;
	int	status;

	if (state == FL_ERASING)
		 timeo += (HZ * 400) / 1000;
	else
		 timeo += (HZ * 20) / 1000;

	/* Apply this short delay always to ensure that we do wait tWB in
	 * any case on any machine. */
	ndelay (100);

	if ((state == FL_ERASING) && (this->options & NAND_IS_AND))
		this->cmdfunc (mtd, NAND_CMD_STATUS_MULTI, -1, -1);
	else
		this->cmdfunc (mtd, NAND_CMD_STATUS, -1, -1);

	while (time_before(jiffies, timeo)) {
		/* Check, if we were interrupted */
		if (this->state != state)
			return 0;

		if (this->dev_ready) {
			if (this->dev_ready(mtd))
				break;
		} else {
			if (this->read_byte(mtd) & NAND_STATUS_READY)
				break;
		}
		yield ();
	}
	status = (int) this->read_byte(mtd);
	return status;

	return 0;
}
#else
static int nand_wait(struct mtd_info *mtd, struct nand_chip *this, int state)
{
	unsigned long	timeo;

	if (state == FL_ERASING)
		timeo = CFG_HZ * 400;
	else
		timeo = CFG_HZ * 20;

	if ((state == FL_ERASING) && (this->options & NAND_IS_AND))
		this->cmdfunc(mtd, NAND_CMD_STATUS_MULTI, -1, -1);
	else
		this->cmdfunc(mtd, NAND_CMD_STATUS, -1, -1);

	reset_timer();

	while (1) {
		if (get_timer(0) > timeo) {
			printf("Timeout!");
			return 0;
			}

		if (this->dev_ready) {
			if (this->dev_ready(mtd))
				break;
		} else {
			if (this->read_byte(mtd) & NAND_STATUS_READY)
				break;
		}
	}
#ifdef PPCHAMELON_NAND_TIMER_HACK
	reset_timer();
	while (get_timer(0) < 10);
#endif /*  PPCHAMELON_NAND_TIMER_HACK */

	return this->read_byte(mtd);
}
#endif

/**
 * nand_write_page - [GENERIC] write one page
 * @mtd:	MTD device structure
 * @this:	NAND chip structure
 * @page: 	startpage inside the chip, must be called with (page & this->pagemask)