doc->pageadrlen =				    nand_flash_ids[i].pageadrlen;				doc->erasesize =				    nand_flash_ids[i].erasesize;				return 1;			}			return 0;		}	}	/* We haven't fully identified the chip. Print as much as we know. */	printk(KERN_WARNING "Unknown flash chip found: %2.2X %2.2X\n",	       id, mfr);	printk(KERN_WARNING "Please report to dwmw2@infradead.org\n");	return 0;}/* DoC_ScanChips: Find all NAND chips present in a DiskOnChip, and identify them */static void DoC_ScanChips(struct DiskOnChip *this){	int floor, chip;	int numchips[MAX_FLOORS];	int maxchips = MAX_CHIPS;	int ret = 1;	this->numchips = 0;	this->mfr = 0;	this->id = 0;	if (DoC_is_Millennium(this))		maxchips = MAX_CHIPS_MIL;	/* For each floor, find the number of valid chips it contains */	for (floor = 0; floor < MAX_FLOORS; floor++) {		ret = 1;		numchips[floor] = 0;		for (chip = 0; chip < maxchips && ret != 0; chip++) {			ret = DoC_IdentChip(this, floor, chip);			if (ret) {				numchips[floor]++;				this->numchips++;			}		}	}	/* If there are none at all that we recognise, bail */	if (!this->numchips) {		printk(KERN_NOTICE "No flash chips recognised.\n");		return;	}	/* Allocate an array to hold the information for each chip */	this->chips = kmalloc(sizeof(struct Nand) * this->numchips, GFP_KERNEL);	if (!this->chips) {		printk(KERN_NOTICE "No memory for allocating chip info structures\n");		return;	}	ret = 0;	/* Fill out the chip array with {floor, chipno} for each 	 * detected chip in the device. */	for (floor = 0; floor < MAX_FLOORS; floor++) {		for (chip = 0; chip < numchips[floor]; chip++) {			this->chips[ret].floor = floor;			this->chips[ret].chip = chip;			this->chips[ret].curadr = 0;			this->chips[ret].curmode = 0x50;			ret++;		}	}	/* Calculate and print the total size of the device */	this->totlen = this->numchips * (1 << this->chipshift);	printk(KERN_INFO "%d flash chips found. Total DiskOnChip size: %ld MiB\n",	       this->numchips, this->totlen >> 20);}static int DoC2k_is_alias(struct DiskOnChip *doc1, struct DiskOnChip *doc2){	int tmp1, tmp2, retval;	if (doc1->physadr == doc2->physadr)		return 1;	/* Use the alias resolution register which was set aside for this	 * purpose. If it's value is the same on both chips, they might	 * be the same chip, and we write to one and check for a change in	 * the other. It's unclear if this register is usuable in the	 * DoC 2000 (it's in the Millennium docs), but it seems to work. */	tmp1 = ReadDOC(doc1->virtadr, AliasResolution);	tmp2 = ReadDOC(doc2->virtadr, AliasResolution);	if (tmp1 != tmp2)		return 0;	WriteDOC((tmp1 + 1) % 0xff, doc1->virtadr, AliasResolution);	tmp2 = ReadDOC(doc2->virtadr, AliasResolution);	if (tmp2 == (tmp1 + 1) % 0xff)		retval = 1;	else		retval = 0;	/* Restore register contents.  May not be necessary, but do it just to	 * be safe. */	WriteDOC(tmp1, doc1->virtadr, AliasResolution);	return retval;}static const char im_name[] = "DoC2k_init";/* This routine is made available to other mtd code via * inter_module_register.  It must only be accessed through * inter_module_get which will bump the use count of this module.  The * addresses passed back in mtd are valid as long as the use count of * this module is non-zero, i.e. between inter_module_get and * inter_module_put.  Keith Owens <kaos@ocs.com.au> 29 Oct 2000. */static void DoC2k_init(struct mtd_info *mtd){	struct DiskOnChip *this = (struct DiskOnChip *) mtd->priv;	struct DiskOnChip *old = NULL;	/* We must avoid being called twice for the same device. */	if (doc2klist)		old = (struct DiskOnChip *) doc2klist->priv;	while (old) {		if (DoC2k_is_alias(old, this)) {			printk(KERN_NOTICE			       "Ignoring DiskOnChip 2000 at 0x%lX - already configured\n",			       this->physadr);			iounmap((void *) this->virtadr);			kfree(mtd);			return;		}		if (old->nextdoc)			old = (struct DiskOnChip *) old->nextdoc->priv;		else			old = NULL;	}	switch (this->ChipID) {	case DOC_ChipID_Doc2k:		mtd->name = "DiskOnChip 2000";		this->ioreg = DoC_2k_CDSN_IO;		break;	case DOC_ChipID_DocMil:		mtd->name = "DiskOnChip Millennium";		this->ioreg = DoC_Mil_CDSN_IO;		break;	}	printk(KERN_NOTICE "%s found at address 0x%lX\n", mtd->name,	       this->physadr);	mtd->type = MTD_NANDFLASH;	mtd->flags = MTD_CAP_NANDFLASH;	mtd->size = 0;	mtd->erasesize = 0;	mtd->oobblock = 512;	mtd->oobsize = 16;	mtd->module = THIS_MODULE;	mtd->erase = doc_erase;	mtd->point = NULL;	mtd->unpoint = NULL;	mtd->read = doc_read;	mtd->write = doc_write;	mtd->read_ecc = doc_read_ecc;	mtd->write_ecc = doc_write_ecc;	mtd->read_oob = doc_read_oob;	mtd->write_oob = doc_write_oob;	mtd->sync = NULL;	this->totlen = 0;	this->numchips = 0;	this->curfloor = -1;	this->curchip = -1;	init_MUTEX(&this->lock);	/* Ident all the chips present. */	DoC_ScanChips(this);	if (!this->totlen) {		kfree(mtd);		iounmap((void *) this->virtadr);	} else {		this->nextdoc = doc2klist;		doc2klist = mtd;		mtd->size = this->totlen;		mtd->erasesize = this->erasesize;		add_mtd_device(mtd);		return;	}}static int doc_read(struct mtd_info *mtd, loff_t from, size_t len,		    size_t * retlen, u_char * buf){	/* Just a special case of doc_read_ecc */	return doc_read_ecc(mtd, from, len, retlen, buf, NULL);}static int doc_read_ecc(struct mtd_info *mtd, loff_t from, size_t len,			size_t * retlen, u_char * buf, u_char * eccbuf){	struct DiskOnChip *this = (struct DiskOnChip *) mtd->priv;	unsigned long docptr;	struct Nand *mychip;	unsigned char syndrome[6];	volatile char dummy;	int i, len256 = 0, ret=0;	docptr = this->virtadr;	/* Don't allow read past end of device */	if (from >= this->totlen)		return -EINVAL;	down(&this->lock);	/* Don't allow a single read to cross a 512-byte block boundary */	if (from + len > ((from | 0x1ff) + 1))		len = ((from | 0x1ff) + 1) - from;	/* The ECC will not be calculated correctly if less than 512 is read */	if (len != 0x200 && eccbuf)		printk(KERN_WARNING		       "ECC needs a full sector read (adr: %lx size %lx)\n",		       (long) from, (long) len);	/* printk("DoC_Read (adr: %lx size %lx)\n", (long) from, (long) len); */	/* Find the chip which is to be used and select it */	mychip = &this->chips[from >> (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,		    (!this->page256		     && (from & 0x100)) ? NAND_CMD_READ1 : NAND_CMD_READ0,		    CDSN_CTRL_WP);	DoC_Address(this, ADDR_COLUMN_PAGE, from, CDSN_CTRL_WP,		    CDSN_CTRL_ECC_IO);	if (eccbuf) {		/* Prime the ECC engine */		WriteDOC(DOC_ECC_RESET, docptr, ECCConf);		WriteDOC(DOC_ECC_EN, docptr, ECCConf);	} else {		/* disable the ECC engine */		WriteDOC(DOC_ECC_RESET, docptr, ECCConf);		WriteDOC(DOC_ECC_DIS, docptr, ECCConf);	}	/* treat crossing 256-byte sector for 2M x 8bits devices */	if (this->page256 && from + len > (from | 0xff) + 1) {		len256 = (from | 0xff) + 1 - from;		DoC_ReadBuf(this, buf, len256);		DoC_Command(this, NAND_CMD_READ0, CDSN_CTRL_WP);		DoC_Address(this, ADDR_COLUMN_PAGE, from + len256,			    CDSN_CTRL_WP, CDSN_CTRL_ECC_IO);	}	DoC_ReadBuf(this, &buf[len256], len - len256);	/* Let the caller know we completed it */	*retlen = len;	if (eccbuf) {		/* Read the ECC data through the DiskOnChip ECC logic */		/* Note: this will work even with 2M x 8bit devices as   */		/*       they have 8 bytes of OOB per 256 page. mf.      */		DoC_ReadBuf(this, eccbuf, 6);		/* Flush the pipeline */		if (DoC_is_Millennium(this)) {			dummy = ReadDOC(docptr, ECCConf);			dummy = ReadDOC(docptr, ECCConf);			i = ReadDOC(docptr, ECCConf);		} else {			dummy = ReadDOC(docptr, 2k_ECCStatus);			dummy = ReadDOC(docptr, 2k_ECCStatus);			i = ReadDOC(docptr, 2k_ECCStatus);		}		/* Check the ECC Status */		if (i & 0x80) {			int nb_errors;			/* There was an ECC error */#ifdef ECC_DEBUG			printk(KERN_ERR "DiskOnChip ECC Error: Read at %lx\n", (long)from);#endif			/* Read the ECC syndrom through the DiskOnChip ECC logic.			   These syndrome will be all ZERO when there is no error */			for (i = 0; i < 6; i++) {				syndrome[i] =				    ReadDOC(docptr, ECCSyndrome0 + i);			}                        nb_errors = doc_decode_ecc(buf, syndrome);#ifdef ECC_DEBUG			printk(KERN_ERR "Errors corrected: %x\n", nb_errors);#endif                        if (nb_errors < 0) {				/* We return error, but have actually done the read. Not that				   this can be told to user-space, via sys_read(), but at least				   MTD-aware stuff can know about it by checking *retlen */				ret = -EIO;                        }		}#ifdef PSYCHO_DEBUG		printk(KERN_DEBUG "ECC DATA at %lxB: %2.2X %2.2X %2.2X %2.2X %2.2X %2.2X\n",			     (long)from, eccbuf[0], eccbuf[1], eccbuf[2],			     eccbuf[3], eccbuf[4], eccbuf[5]);#endif				/* disable the ECC engine */		WriteDOC(DOC_ECC_DIS, docptr , ECCConf);	}	/* according to 11.4.1, we need to wait for the busy line          * drop if we read to the end of the page.  */	if(0 == ((from + *retlen) & 0x1ff))	{	    DoC_WaitReady(this);	}	up(&this->lock);	return ret;}static int doc_write(struct mtd_info *mtd, loff_t to, size_t len,		     size_t * retlen, const u_char * buf){	char eccbuf[6];	return doc_write_ecc(mtd, to, len, retlen, buf, eccbuf);}static int doc_write_ecc(struct mtd_info *mtd, loff_t to, size_t len,			 size_t * retlen, const u_char * buf,			 u_char * eccbuf){	struct DiskOnChip *this = (struct DiskOnChip *) mtd->priv;	int di; /* Yes, DI is a hangover from when I was disassembling the binary driver */	unsigned long docptr;	volatile char dummy;	int len256 = 0;	struct Nand *mychip;	docptr = this->virtadr;	/* Don't allow write past end of device */	if (to >= this->totlen)		return -EINVAL;	down(&this->lock);	/* Don't allow a single write to cross a 512-byte block boundary */	if (to + len > ((to | 0x1ff) + 1))		len = ((to | 0x1ff) + 1) - to;	/* The ECC will not be calculated correctly if less than 512 is written */	if (len != 0x200 && eccbuf)		printk(KERN_WARNING		       "ECC needs a full sector write (adr: %lx size %lx)\n",		       (long) to, (long) len);	/* printk("DoC_Write (adr: %lx size %lx)\n", (long) to, (long) len); */	/* Find the chip which is to be used and select it */	mychip = &this->chips[to >> (this->chipshift)];