doc2000.c

基于linux-2.6.28的mtd驱动

		DoC_Command(this,
			    (!this->page256
			     && (to & 0x100)) ? NAND_CMD_READ1 : NAND_CMD_READ0,
			    CDSN_CTRL_WP);

		DoC_Command(this, NAND_CMD_SEQIN, 0);
		DoC_Address(this, ADDR_COLUMN_PAGE, to, 0, CDSN_CTRL_ECC_IO);

		/* Prime the ECC engine */
		WriteDOC(DOC_ECC_RESET, docptr, ECCConf);
		WriteDOC(DOC_ECC_EN | DOC_ECC_RW, docptr, ECCConf);

		/* treat crossing 256-byte sector for 2M x 8bits devices */
		if (this->page256 && to + len > (to | 0xff) + 1) {
			len256 = (to | 0xff) + 1 - to;
			DoC_WriteBuf(this, buf, len256);

			DoC_Command(this, NAND_CMD_PAGEPROG, 0);

			DoC_Command(this, NAND_CMD_STATUS, CDSN_CTRL_WP);
			/* There's an implicit DoC_WaitReady() in DoC_Command */

			dummy = ReadDOC(docptr, CDSNSlowIO);
			DoC_Delay(this, 2);

			if (ReadDOC_(docptr, this->ioreg) & 1) {
				printk(KERN_ERR "Error programming flash\n");
				/* Error in programming */
				*retlen = 0;
				mutex_unlock(&this->lock);
				return -EIO;
			}

			DoC_Command(this, NAND_CMD_SEQIN, 0);
			DoC_Address(this, ADDR_COLUMN_PAGE, to + len256, 0,
				    CDSN_CTRL_ECC_IO);
		}

		DoC_WriteBuf(this, &buf[len256], len - len256);

		WriteDOC(CDSN_CTRL_ECC_IO | CDSN_CTRL_CE, docptr, CDSNControl);

		if (DoC_is_Millennium(this)) {
			WriteDOC(0, docptr, NOP);
			WriteDOC(0, docptr, NOP);
			WriteDOC(0, docptr, NOP);
		} else {
			WriteDOC_(0, docptr, this->ioreg);
			WriteDOC_(0, docptr, this->ioreg);
			WriteDOC_(0, docptr, this->ioreg);
		}

		WriteDOC(CDSN_CTRL_ECC_IO | CDSN_CTRL_FLASH_IO | CDSN_CTRL_CE, docptr,
			 CDSNControl);

		/* Read the ECC data through the DiskOnChip ECC logic */
		for (di = 0; di < 6; di++) {
			eccbuf[di] = ReadDOC(docptr, ECCSyndrome0 + di);
		}

		/* Reset the ECC engine */
		WriteDOC(DOC_ECC_DIS, docptr, ECCConf);

#ifdef PSYCHO_DEBUG
		printk
			("OOB data at %lx is %2.2X %2.2X %2.2X %2.2X %2.2X %2.2X\n",
			 (long) to, eccbuf[0], eccbuf[1], eccbuf[2], eccbuf[3],
			 eccbuf[4], eccbuf[5]);
#endif
		DoC_Command(this, NAND_CMD_PAGEPROG, 0);

		DoC_Command(this, NAND_CMD_STATUS, CDSN_CTRL_WP);
		/* There's an implicit DoC_WaitReady() in DoC_Command */

		if (DoC_is_Millennium(this)) {
			ReadDOC(docptr, ReadPipeInit);
			status = ReadDOC(docptr, LastDataRead);
		} else {
			dummy = ReadDOC(docptr, CDSNSlowIO);
			DoC_Delay(this, 2);
			status = ReadDOC_(docptr, this->ioreg);
		}

		if (status & 1) {
			printk(KERN_ERR "Error programming flash\n");
			/* Error in programming */
			*retlen = 0;
			mutex_unlock(&this->lock);
			return -EIO;
		}

		/* Let the caller know we completed it */
		*retlen += len;

		{
			unsigned char x[8];
			size_t dummy;
			int ret;

			/* Write the ECC data to flash */
			for (di=0; di<6; di++)
				x[di] = eccbuf[di];

			x[6]=0x55;
			x[7]=0x55;

			ret = doc_write_oob_nolock(mtd, to, 8, &dummy, x);
			if (ret) {
				mutex_unlock(&this->lock);
				return ret;
			}
		}

		to += len;
		left -= len;
		buf += len;
	}

	mutex_unlock(&this->lock);
	return 0;
}

static int doc_read_oob(struct mtd_info *mtd, loff_t ofs,
			struct mtd_oob_ops *ops)
{
	struct DiskOnChip *this = mtd->priv;
	int len256 = 0, ret;
	struct Nand *mychip;
	uint8_t *buf = ops->oobbuf;
	size_t len = ops->len;

	BUG_ON(ops->mode != MTD_OOB_PLACE);

	ofs += ops->ooboffs;

	mutex_lock(&this->lock);

	mychip = &this->chips[ofs >> this->chipshift];

	if (this->curfloor != mychip->floor) {
		DoC_SelectFloor(this, mychip->floor);
		DoC_SelectChip(this, mychip->chip);
	} else if (this->curchip != mychip->chip) {
		DoC_SelectChip(this, mychip->chip);
	}
	this->curfloor = mychip->floor;
	this->curchip = mychip->chip;

	/* update address for 2M x 8bit devices. OOB starts on the second */
	/* page to maintain compatibility with doc_read_ecc. */
	if (this->page256) {
		if (!(ofs & 0x8))
			ofs += 0x100;
		else
			ofs -= 0x8;
	}

	DoC_Command(this, NAND_CMD_READOOB, CDSN_CTRL_WP);
	DoC_Address(this, ADDR_COLUMN_PAGE, ofs, CDSN_CTRL_WP, 0);

	/* treat crossing 8-byte OOB data for 2M x 8bit devices */
	/* Note: datasheet says it should automaticaly wrap to the */
	/*       next OOB block, but it didn't work here. mf.      */
	if (this->page256 && ofs + len > (ofs | 0x7) + 1) {
		len256 = (ofs | 0x7) + 1 - ofs;
		DoC_ReadBuf(this, buf, len256);

		DoC_Command(this, NAND_CMD_READOOB, CDSN_CTRL_WP);
		DoC_Address(this, ADDR_COLUMN_PAGE, ofs & (~0x1ff),
			    CDSN_CTRL_WP, 0);
	}

	DoC_ReadBuf(this, &buf[len256], len - len256);

	ops->retlen = len;
	/* Reading the full OOB data drops us off of the end of the page,
         * causing the flash device to go into busy mode, so we need
         * to wait until ready 11.4.1 and Toshiba TC58256FT docs */

	ret = DoC_WaitReady(this);

	mutex_unlock(&this->lock);
	return ret;

}

static int doc_write_oob_nolock(struct mtd_info *mtd, loff_t ofs, size_t len,
				size_t * retlen, const u_char * buf)
{
	struct DiskOnChip *this = mtd->priv;
	int len256 = 0;
	void __iomem *docptr = this->virtadr;
	struct Nand *mychip = &this->chips[ofs >> this->chipshift];
	volatile int dummy;
	int status;

	//      printk("doc_write_oob(%lx, %d): %2.2X %2.2X %2.2X %2.2X ... %2.2X %2.2X .. %2.2X %2.2X\n",(long)ofs, len,
	//   buf[0], buf[1], buf[2], buf[3], buf[8], buf[9], buf[14],buf[15]);

	/* Find the chip which is to be used and select it */
	if (this->curfloor != mychip->floor) {
		DoC_SelectFloor(this, mychip->floor);
		DoC_SelectChip(this, mychip->chip);
	} else if (this->curchip != mychip->chip) {
		DoC_SelectChip(this, mychip->chip);
	}
	this->curfloor = mychip->floor;
	this->curchip = mychip->chip;

	/* disable the ECC engine */
	WriteDOC (DOC_ECC_RESET, docptr, ECCConf);
	WriteDOC (DOC_ECC_DIS, docptr, ECCConf);

	/* Reset the chip, see Software Requirement 11.4 item 1. */
	DoC_Command(this, NAND_CMD_RESET, CDSN_CTRL_WP);

	/* issue the Read2 command to set the pointer to the Spare Data Area. */
	DoC_Command(this, NAND_CMD_READOOB, CDSN_CTRL_WP);

	/* update address for 2M x 8bit devices. OOB starts on the second */
	/* page to maintain compatibility with doc_read_ecc. */
	if (this->page256) {
		if (!(ofs & 0x8))
			ofs += 0x100;
		else
			ofs -= 0x8;
	}

	/* issue the Serial Data In command to initial the Page Program process */
	DoC_Command(this, NAND_CMD_SEQIN, 0);
	DoC_Address(this, ADDR_COLUMN_PAGE, ofs, 0, 0);

	/* treat crossing 8-byte OOB data for 2M x 8bit devices */
	/* Note: datasheet says it should automaticaly wrap to the */
	/*       next OOB block, but it didn't work here. mf.      */
	if (this->page256 && ofs + len > (ofs | 0x7) + 1) {
		len256 = (ofs | 0x7) + 1 - ofs;
		DoC_WriteBuf(this, buf, len256);

		DoC_Command(this, NAND_CMD_PAGEPROG, 0);
		DoC_Command(this, NAND_CMD_STATUS, 0);
		/* DoC_WaitReady() is implicit in DoC_Command */

		if (DoC_is_Millennium(this)) {
			ReadDOC(docptr, ReadPipeInit);
			status = ReadDOC(docptr, LastDataRead);
		} else {
			dummy = ReadDOC(docptr, CDSNSlowIO);
			DoC_Delay(this, 2);
			status = ReadDOC_(docptr, this->ioreg);
		}

		if (status & 1) {
			printk(KERN_ERR "Error programming oob data\n");
			/* There was an error */
			*retlen = 0;
			return -EIO;
		}
		DoC_Command(this, NAND_CMD_SEQIN, 0);
		DoC_Address(this, ADDR_COLUMN_PAGE, ofs & (~0x1ff), 0, 0);
	}

	DoC_WriteBuf(this, &buf[len256], len - len256);

	DoC_Command(this, NAND_CMD_PAGEPROG, 0);
	DoC_Command(this, NAND_CMD_STATUS, 0);
	/* DoC_WaitReady() is implicit in DoC_Command */

	if (DoC_is_Millennium(this)) {
		ReadDOC(docptr, ReadPipeInit);
		status = ReadDOC(docptr, LastDataRead);
	} else {
		dummy = ReadDOC(docptr, CDSNSlowIO);
		DoC_Delay(this, 2);
		status = ReadDOC_(docptr, this->ioreg);
	}

	if (status & 1) {
		printk(KERN_ERR "Error programming oob data\n");
		/* There was an error */
		*retlen = 0;
		return -EIO;
	}

	*retlen = len;
	return 0;

}

static int doc_write_oob(struct mtd_info *mtd, loff_t ofs,
			 struct mtd_oob_ops *ops)
{
	struct DiskOnChip *this = mtd->priv;
	int ret;

	BUG_ON(ops->mode != MTD_OOB_PLACE);

	mutex_lock(&this->lock);
	ret = doc_write_oob_nolock(mtd, ofs + ops->ooboffs, ops->len,
				   &ops->retlen, ops->oobbuf);

	mutex_unlock(&this->lock);
	return ret;
}

static int doc_erase(struct mtd_info *mtd, struct erase_info *instr)
{
	struct DiskOnChip *this = mtd->priv;
	__u32 ofs = instr->addr;
	__u32 len = instr->len;
	volatile int dummy;
	void __iomem *docptr = this->virtadr;
	struct Nand *mychip;
	int status;

 	mutex_lock(&this->lock);

	if (ofs & (mtd->erasesize-1) || len & (mtd->erasesize-1)) {
		mutex_unlock(&this->lock);
		return -EINVAL;
	}

	instr->state = MTD_ERASING;

	/* FIXME: Do this in the background. Use timers or schedule_task() */
	while(len) {
		mychip = &this->chips[ofs >> this->chipshift];

		if (this->curfloor != mychip->floor) {
			DoC_SelectFloor(this, mychip->floor);
			DoC_SelectChip(this, mychip->chip);
		} else if (this->curchip != mychip->chip) {
			DoC_SelectChip(this, mychip->chip);
		}
		this->curfloor = mychip->floor;
		this->curchip = mychip->chip;

		DoC_Command(this, NAND_CMD_ERASE1, 0);
		DoC_Address(this, ADDR_PAGE, ofs, 0, 0);
		DoC_Command(this, NAND_CMD_ERASE2, 0);

		DoC_Command(this, NAND_CMD_STATUS, CDSN_CTRL_WP);

		if (DoC_is_Millennium(this)) {
			ReadDOC(docptr, ReadPipeInit);
			status = ReadDOC(docptr, LastDataRead);
		} else {
			dummy = ReadDOC(docptr, CDSNSlowIO);
			DoC_Delay(this, 2);
			status = ReadDOC_(docptr, this->ioreg);
		}

		if (status & 1) {
			printk(KERN_ERR "Error erasing at 0x%x\n", ofs);
			/* There was an error */
			instr->state = MTD_ERASE_FAILED;
			goto callback;
		}
		ofs += mtd->erasesize;
		len -= mtd->erasesize;
	}
	instr->state = MTD_ERASE_DONE;

 callback:
	mtd_erase_callback(instr);

	mutex_unlock(&this->lock);
	return 0;
}


/****************************************************************************
 *
 * Module stuff
 *
 ****************************************************************************/

static void __exit cleanup_doc2000(void)
{
	struct mtd_info *mtd;
	struct DiskOnChip *this;

	while ((mtd = doc2klist)) {
		this = mtd->priv;
		doc2klist = this->nextdoc;

		del_mtd_device(mtd);

		iounmap(this->virtadr);
		kfree(this->chips);
		kfree(mtd);
	}
}

module_exit(cleanup_doc2000);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("David Woodhouse <[e-mail]> et al.");
MODULE_DESCRIPTION("MTD driver for DiskOnChip 2000 and Millennium");