doc2001plus.c

linux-2.6.15.6

/*
 * Linux driver for Disk-On-Chip Millennium Plus
 *
 * (c) 2002-2003 Greg Ungerer <[e-mail]>
 * (c) 2002-2003 SnapGear Inc
 * (c) 1999 Machine Vision Holdings, Inc.
 * (c) 1999, 2000 David Woodhouse <[e-mail]>
 *
 * $Id: doc2001plus.c,v 1.14 2005/11/07 11:14:24 gleixner Exp $
 *
 * Released under GPL
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <asm/errno.h>
#include <asm/io.h>
#include <asm/uaccess.h>
#include <linux/miscdevice.h>
#include <linux/pci.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/sched.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/bitops.h>

#include <linux/mtd/mtd.h>
#include <linux/mtd/nand.h>
#include <linux/mtd/doc2000.h>

/* #define ECC_DEBUG */

/* I have no idea why some DoC chips can not use memcop_form|to_io().
 * This may be due to the different revisions of the ASIC controller built-in or
 * simplily a QA/Bug issue. Who knows ?? If you have trouble, please uncomment
 * this:*/
#undef USE_MEMCPY

static int doc_read(struct mtd_info *mtd, loff_t from, size_t len,
		size_t *retlen, u_char *buf);
static int doc_write(struct mtd_info *mtd, loff_t to, size_t len,
		size_t *retlen, const u_char *buf);
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 nand_oobinfo *oobsel);
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 nand_oobinfo *oobsel);
static int doc_read_oob(struct mtd_info *mtd, loff_t ofs, size_t len,
		size_t *retlen, u_char *buf);
static int doc_write_oob(struct mtd_info *mtd, loff_t ofs, size_t len,
		size_t *retlen, const u_char *buf);
static int doc_erase (struct mtd_info *mtd, struct erase_info *instr);

static struct mtd_info *docmilpluslist = NULL;


/* Perform the required delay cycles by writing to the NOP register */
static void DoC_Delay(void __iomem * docptr, int cycles)
{
	int i;

	for (i = 0; (i < cycles); i++)
		WriteDOC(0, docptr, Mplus_NOP);
}

#define	CDSN_CTRL_FR_B_MASK	(CDSN_CTRL_FR_B0 | CDSN_CTRL_FR_B1)

/* DOC_WaitReady: Wait for RDY line to be asserted by the flash chip */
static int _DoC_WaitReady(void __iomem * docptr)
{
	unsigned int c = 0xffff;

	DEBUG(MTD_DEBUG_LEVEL3,
	      "_DoC_WaitReady called for out-of-line wait\n");

	/* Out-of-line routine to wait for chip response */
	while (((ReadDOC(docptr, Mplus_FlashControl) & CDSN_CTRL_FR_B_MASK) != CDSN_CTRL_FR_B_MASK) && --c)
		;

	if (c == 0)
		DEBUG(MTD_DEBUG_LEVEL2, "_DoC_WaitReady timed out.\n");

	return (c == 0);
}

static inline int DoC_WaitReady(void __iomem * docptr)
{
	/* This is inline, to optimise the common case, where it's ready instantly */
	int ret = 0;

	/* read form NOP register should be issued prior to the read from CDSNControl
	   see Software Requirement 11.4 item 2. */
	DoC_Delay(docptr, 4);

	if ((ReadDOC(docptr, Mplus_FlashControl) & CDSN_CTRL_FR_B_MASK) != CDSN_CTRL_FR_B_MASK)
		/* Call the out-of-line routine to wait */
		ret = _DoC_WaitReady(docptr);

	return ret;
}

/* For some reason the Millennium Plus seems to occassionally put itself
 * into reset mode. For me this happens randomly, with no pattern that I
 * can detect. M-systems suggest always check this on any block level
 * operation and setting to normal mode if in reset mode.
 */
static inline void DoC_CheckASIC(void __iomem * docptr)
{
	/* Make sure the DoC is in normal mode */
	if ((ReadDOC(docptr, Mplus_DOCControl) & DOC_MODE_NORMAL) == 0) {
		WriteDOC((DOC_MODE_NORMAL | DOC_MODE_MDWREN), docptr, Mplus_DOCControl);
		WriteDOC(~(DOC_MODE_NORMAL | DOC_MODE_MDWREN), docptr, Mplus_CtrlConfirm);
	}
}

/* DoC_Command: Send a flash command to the flash chip through the Flash
 * command register. Need 2 Write Pipeline Terminates to complete send.
 */
static inline void DoC_Command(void __iomem * docptr, unsigned char command,
			       unsigned char xtraflags)
{
	WriteDOC(command, docptr, Mplus_FlashCmd);
	WriteDOC(command, docptr, Mplus_WritePipeTerm);
	WriteDOC(command, docptr, Mplus_WritePipeTerm);
}

/* DoC_Address: Set the current address for the flash chip through the Flash
 * Address register. Need 2 Write Pipeline Terminates to complete send.
 */
static inline void DoC_Address(struct DiskOnChip *doc, int numbytes,
			       unsigned long ofs, unsigned char xtraflags1,
			       unsigned char xtraflags2)
{
	void __iomem * docptr = doc->virtadr;

	/* Allow for possible Mill Plus internal flash interleaving */
	ofs >>= doc->interleave;

	switch (numbytes) {
	case 1:
		/* Send single byte, bits 0-7. */
		WriteDOC(ofs & 0xff, docptr, Mplus_FlashAddress);
		break;
	case 2:
		/* Send bits 9-16 followed by 17-23 */
		WriteDOC((ofs >> 9)  & 0xff, docptr, Mplus_FlashAddress);
		WriteDOC((ofs >> 17) & 0xff, docptr, Mplus_FlashAddress);
		break;
	case 3:
		/* Send 0-7, 9-16, then 17-23 */
		WriteDOC(ofs & 0xff, docptr, Mplus_FlashAddress);
		WriteDOC((ofs >> 9)  & 0xff, docptr, Mplus_FlashAddress);
		WriteDOC((ofs >> 17) & 0xff, docptr, Mplus_FlashAddress);
		break;
	default:
		return;
	}

	WriteDOC(0x00, docptr, Mplus_WritePipeTerm);
	WriteDOC(0x00, docptr, Mplus_WritePipeTerm);
}

/* DoC_SelectChip: Select a given flash chip within the current floor */
static int DoC_SelectChip(void __iomem * docptr, int chip)
{
	/* No choice for flash chip on Millennium Plus */
	return 0;
}

/* DoC_SelectFloor: Select a given floor (bank of flash chips) */
static int DoC_SelectFloor(void __iomem * docptr, int floor)
{
	WriteDOC((floor & 0x3), docptr, Mplus_DeviceSelect);
	return 0;
}

/*
 * Translate the given offset into the appropriate command and offset.
 * This does the mapping using the 16bit interleave layout defined by
 * M-Systems, and looks like this for a sector pair:
 *  +-----------+-------+-------+-------+--------------+---------+-----------+
 *  | 0 --- 511 |512-517|518-519|520-521| 522 --- 1033 |1034-1039|1040 - 1055|
 *  +-----------+-------+-------+-------+--------------+---------+-----------+
 *  | Data 0    | ECC 0 |Flags0 |Flags1 | Data 1       |ECC 1    | OOB 1 + 2 |
 *  +-----------+-------+-------+-------+--------------+---------+-----------+
 */
/* FIXME: This lives in INFTL not here. Other users of flash devices
   may not want it */
static unsigned int DoC_GetDataOffset(struct mtd_info *mtd, loff_t *from)
{
	struct DiskOnChip *this = mtd->priv;

	if (this->interleave) {
		unsigned int ofs = *from & 0x3ff;
		unsigned int cmd;

		if (ofs < 512) {
			cmd = NAND_CMD_READ0;
			ofs &= 0x1ff;
		} else if (ofs < 1014) {
			cmd = NAND_CMD_READ1;
			ofs = (ofs & 0x1ff) + 10;
		} else {
			cmd = NAND_CMD_READOOB;
			ofs = ofs - 1014;
		}

		*from = (*from & ~0x3ff) | ofs;
		return cmd;
	} else {
		/* No interleave */
		if ((*from) & 0x100)
			return NAND_CMD_READ1;
		return NAND_CMD_READ0;
	}
}

static unsigned int DoC_GetECCOffset(struct mtd_info *mtd, loff_t *from)
{
	unsigned int ofs, cmd;

	if (*from & 0x200) {
		cmd = NAND_CMD_READOOB;
		ofs = 10 + (*from & 0xf);
	} else {
		cmd = NAND_CMD_READ1;
		ofs = (*from & 0xf);
	}

	*from = (*from & ~0x3ff) | ofs;
	return cmd;
}

static unsigned int DoC_GetFlagsOffset(struct mtd_info *mtd, loff_t *from)
{
	unsigned int ofs, cmd;

	cmd = NAND_CMD_READ1;
	ofs = (*from & 0x200) ? 8 : 6;
	*from = (*from & ~0x3ff) | ofs;
	return cmd;
}

static unsigned int DoC_GetHdrOffset(struct mtd_info *mtd, loff_t *from)
{
	unsigned int ofs, cmd;

	cmd = NAND_CMD_READOOB;
	ofs = (*from & 0x200) ? 24 : 16;
	*from = (*from & ~0x3ff) | ofs;
	return cmd;
}

static inline void MemReadDOC(void __iomem * docptr, unsigned char *buf, int len)
{
#ifndef USE_MEMCPY
	int i;
	for (i = 0; i < len; i++)
		buf[i] = ReadDOC(docptr, Mil_CDSN_IO + i);
#else
	memcpy_fromio(buf, docptr + DoC_Mil_CDSN_IO, len);
#endif
}

static inline void MemWriteDOC(void __iomem * docptr, unsigned char *buf, int len)
{
#ifndef USE_MEMCPY
	int i;
	for (i = 0; i < len; i++)
		WriteDOC(buf[i], docptr, Mil_CDSN_IO + i);
#else
	memcpy_toio(docptr + DoC_Mil_CDSN_IO, buf, len);
#endif
}

/* DoC_IdentChip: Identify a given NAND chip given {floor,chip} */
static int DoC_IdentChip(struct DiskOnChip *doc, int floor, int chip)
{
	int mfr, id, i, j;
	volatile char dummy;
	void __iomem * docptr = doc->virtadr;

	/* Page in the required floor/chip */
	DoC_SelectFloor(docptr, floor);
	DoC_SelectChip(docptr, chip);

	/* Millennium Plus bus cycle sequence as per figure 2, section 2.4 */
	WriteDOC((DOC_FLASH_CE | DOC_FLASH_WP), docptr, Mplus_FlashSelect);

	/* Reset the chip, see Software Requirement 11.4 item 1. */
	DoC_Command(docptr, NAND_CMD_RESET, 0);
	DoC_WaitReady(docptr);

	/* Read the NAND chip ID: 1. Send ReadID command */
	DoC_Command(docptr, NAND_CMD_READID, 0);

	/* Read the NAND chip ID: 2. Send address byte zero */
	DoC_Address(doc, 1, 0x00, 0, 0x00);

	WriteDOC(0, docptr, Mplus_FlashControl);
	DoC_WaitReady(docptr);

	/* Read the manufacturer and device id codes of the flash device through
	   CDSN IO register see Software Requirement 11.4 item 5.*/
	dummy = ReadDOC(docptr, Mplus_ReadPipeInit);
	dummy = ReadDOC(docptr, Mplus_ReadPipeInit);

	mfr = ReadDOC(docptr, Mil_CDSN_IO);
	if (doc->interleave)
		dummy = ReadDOC(docptr, Mil_CDSN_IO); /* 2 way interleave */

	id  = ReadDOC(docptr, Mil_CDSN_IO);
	if (doc->interleave)
		dummy = ReadDOC(docptr, Mil_CDSN_IO); /* 2 way interleave */

	dummy = ReadDOC(docptr, Mplus_LastDataRead);
	dummy = ReadDOC(docptr, Mplus_LastDataRead);

	/* Disable flash internally */
	WriteDOC(0, docptr, Mplus_FlashSelect);

	/* No response - return failure */
	if (mfr == 0xff || mfr == 0)
		return 0;

	for (i = 0; nand_flash_ids[i].name != NULL; i++) {
		if (id == nand_flash_ids[i].id) {
			/* Try to identify manufacturer */
			for (j = 0; nand_manuf_ids[j].id != 0x0; j++) {
				if (nand_manuf_ids[j].id == mfr)
					break;
			}
			printk(KERN_INFO "Flash chip found: Manufacturer ID: %2.2X, "
			       "Chip ID: %2.2X (%s:%s)\n", mfr, id,
			       nand_manuf_ids[j].name, nand_flash_ids[i].name);
			doc->mfr = mfr;
			doc->id = id;
			doc->chipshift = ffs((nand_flash_ids[i].chipsize << 20)) - 1;
			doc->erasesize = nand_flash_ids[i].erasesize << doc->interleave;
			break;
		}
	}

	if (nand_flash_ids[i].name == NULL)
		return 0;
	return 1;
}

/* 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_MPLUS];
	int ret;

	this->numchips = 0;
	this->mfr = 0;
	this->id = 0;

	/* Work out the intended interleave setting */
	this->interleave = 0;
	if (this->ChipID == DOC_ChipID_DocMilPlus32)
		this->interleave = 1;

	/* Check the ASIC agrees */
	if ( (this->interleave << 2) !=
	     (ReadDOC(this->virtadr, Mplus_Configuration) & 4)) {
		u_char conf = ReadDOC(this->virtadr, Mplus_Configuration);
		printk(KERN_NOTICE "Setting DiskOnChip Millennium Plus interleave to %s\n",
		       this->interleave?"on (16-bit)":"off (8-bit)");
		conf ^= 4;
		WriteDOC(conf, this->virtadr, Mplus_Configuration);
	}

	/* For each floor, find the number of valid chips it contains */
	for (floor = 0,ret = 1; floor < MAX_FLOORS_MPLUS; floor++) {
		numchips[floor] = 0;
		for (chip = 0; chip < MAX_CHIPS_MPLUS && ret != 0; chip++) {
			ret = DoC_IdentChip(this, floor, chip);
			if (ret) {
				numchips[floor]++;
				this->numchips++;
			}