nand.c

ARM的著名的启动代码 vivi s3c2440部分已测试通过

/*
 * vivi/drivers/mtd/nand/nand.c: 
 *
 * Based on linux/drivers/mtd/nand/nand.c
 *
 * $Id: smc_core.c,v 1.3 2002/08/10 07:47:08 nandy Exp $
 *
 *
 * 棱淬:
 *   恐 this->oobblock捞扼绊 沁阑鳖? thsi->oobblcok_ofs捞扼绊 窍搁
 *   粱歹 疙犬窍瘤 臼阑鳖?
 */

#include "config.h"
#include "mtd/mtd.h"
#include "machine.h"
#include "mtd/nand.h"
#include "mtd/nand_ids.h"
#include "mtd/nand_ecc.h"
#include "time.h"
#include "printk.h"
#include "heap.h"
#include "io.h"
#include <types.h>
#include <errno.h>


static int nand_read_ecc (struct mtd_info *mtd, loff_t from, size_t len,
			  size_t * retlen, u_char * buf, u_char * oob_buf, struct nand_oobinfo *oobsel);

static int nand_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 void nand_select_chip(struct mtd_info *mtd, int chip)
{
	struct nand_chip *this = mtd->priv;
	switch(chip) {
	case -1:
		this->hwcontrol(mtd, NAND_CTL_CLRNCE);	
		break;
	case 0:
		this->hwcontrol(mtd, NAND_CTL_SETNCE);
		break;

	default:
		;
	}
}

static void nand_write_buf(struct mtd_info *mtd, const u_char *buf, int len)
{
	int i;
	struct nand_chip *this = mtd->priv;

	for (i=0; i<len; i++)
		this->write_byte(mtd,buf[i]);
}

static void nand_read_buf(struct mtd_info *mtd, u_char *buf, int len)
{
	int i;
	struct nand_chip *this = mtd->priv;

	for (i=0; i<len; i++)
		buf[i] = this->read_byte(mtd);

}

static int nand_verify_buf(struct mtd_info *mtd, const u_char *buf, int len)
{
	int i;
	struct nand_chip *this = mtd->priv;

	for (i=0; i<len; i++)
		if (buf[i] != this->read_byte(mtd))
			return i;

	return 0;
}

/* Appropriate chip should already be selected */
static int nand_block_bad(struct mtd_info *mtd, unsigned long page)
{
	struct nand_chip *this = mtd->priv;
	
	this->cmdfunc (mtd, NAND_CMD_READOOB, NAND_BADBLOCK_POS, page);
	if (this->read_byte(mtd) != 0xff)
		return 1;

	return 0;
}

/*
 * Send command to NAND device
 */
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);
	this->hwcontrol(mtd,NAND_CTL_DAT_OUT);
	/*
	 * 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_cmd(mtd, readcmd);
	}
//	this->write_byte(mtd, command);
	this->write_cmd(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)
//			this->write_byte(mtd, column);
			this->write_addr(mtd, column);
		if (page_addr != -1) {
//			this->write_byte(mtd, (unsigned char) (page_addr & 0xff));
			this->write_addr(mtd, (unsigned char) (page_addr & 0xff));
//			this->write_byte(mtd, (unsigned char) ((page_addr >> 8) & 0xff));
			this->write_addr(mtd, (unsigned char) ((page_addr >> 8) & 0xff));
			/* One more address cycle for higher density devices */
			if (mtd->size & 0x0c000000) 
//				this->write_byte(mtd, (unsigned char) ((page_addr >> 16) & 0x0f));
				this->write_addr(mtd, (unsigned char) ((page_addr >> 16) & 0xff));
		}
		/* Latch in address */
		this->hwcontrol(mtd, NAND_CTL_CLRALE);
		this->hwcontrol(mtd,NAND_CTL_DAT_IN);
	}
	
	/* 
	 * 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->write_cmd(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
		*/
		while (!this->dev_ready(mtd)){
			udelay (this->chip_delay);
			return;
		}	
	}
	
	/* wait until command is processed */
	while (!this->dev_ready(mtd))
		udelay (this->chip_delay);
}

static int nand_wait(struct mtd_info *mtd,struct nand_chip *this,int state)
{
	int i;
	int status;
	for(i=0;i<32;i++){

		udelay(125);

		this->cmdfunc(mtd,NAND_CMD_STATUS,-1,-1);
	
		if(this->dev_ready){
			if(this->dev_ready(mtd))
				break;
		}
		if(this->read_byte(mtd)&0x40)
			break;
	}
	status=(int)this->read_byte(mtd);
	
	return status;	
}
/*
 *	Nand_page_program function is used for write and writev !
 *	This function will always program a full page of data
 *	If you call it with a non page aligned buffer, you're lost :)
 */
static int nand_write_page (struct mtd_info *mtd, struct nand_chip *this,
			    int page, int col, int last, u_char *oob_buf, struct nand_oobinfo *oobsel)
{
	int 	i,status;
	u_char	ecc_code[6], *oob_data;
	int	eccmode = oobsel->useecc ? this->eccmode : NAND_ECC_NONE;
	int  	*oob_config = oobsel->eccpos;
	
	/* pad oob area, if we have no oob buffer from fs-driver */
	if (!oob_buf) {
		oob_data = &this->data_buf[mtd->oobblock];
		for (i = 0; i < mtd->oobsize; i++)
			oob_data[i] = 0xff;
	} else 
		oob_data = oob_buf;
	/* software ecc 3 Bytes ECC / 256 Byte Data ? */
	if (eccmode == NAND_ECC_SOFT) {
		/* Read back previous written data, if col > 0 */
		if (col) {
			this->cmdfunc (mtd, NAND_CMD_READ0, 0, page);
			this->read_buf(mtd,&this->data_poi[0],col);
		}
		if ((col < this->eccsize) && (last >= this->eccsize)) {
			this->calculate_ecc (mtd,&this->data_poi[0], &(ecc_code[0]));
			for (i = 0; i < 3; i++)
				oob_data[oob_config[i]] = ecc_code[i];
		}
		/* Calculate and write the second ECC if we have enough data */
		if ((mtd->oobblock == 512) && (last == 512)) {
			this->calculate_ecc (mtd,&this->data_poi[256], &(ecc_code[3]));
			for (i = 3; i < 6; i++)
				oob_data[oob_config[i]] = ecc_code[i];
		} 
	} else {
		/* For hardware ECC skip ECC, if we have no full page write */
		if (eccmode != NAND_ECC_NONE && (col || last != mtd->oobblock))
			eccmode = NAND_ECC_NONE;
	}			

	/* Prepad for partial page programming !!! */
	for (i = 0; i < col; i++)
		this->data_poi[i] = 0xff;

	/* Postpad for partial page programming !!! oob is already padded */
	for (i = last; i < mtd->oobblock; i++)
		this->data_poi[i] = 0xff;
	
	/* Send command to begin auto page programming */
	this->cmdfunc (mtd, NAND_CMD_SEQIN, 0x00, page);

	/* Write out complete page of data, take care of eccmode */
	switch (eccmode) {
	/* No ecc and software ecc 3/256, write all */
	case NAND_ECC_NONE:
//		printk (KERN_WARNING "Writing data without ECC to NAND-FLASH is not recommended\n");
//		this->write_buf(mtd, this->data_poi, mtd->oobblock);
//		break;
	case NAND_ECC_SOFT:
//		this->calculate_ecc(mtd, &this->data_poi[0], &(ecc_code[0]));
//		for (i = 0; i < 3; i++)
//			oob_data[oob_config[i]] = ecc_code[i];
		/* Calculate and write the second ECC for 512 Byte page size */
//		if (mtd->oobblock == 512) {
//			this->calculate_ecc(mtd, &this->data_poi[256], &(ecc_code[3]));
//			for (i = 3; i < 6; i++)
//				oob_data[oob_config[i]] = ecc_code[i];
//		} 
		this->write_buf(mtd, this->data_poi, mtd->oobblock);
		break;
		
	/* Hardware ecc 3 byte / 256 data, write first half, get ecc, then second, if 512 byte pagesize */	
	case NAND_ECC_HW3_256:		
		this->enable_hwecc(mtd, NAND_ECC_WRITE);	/* enable hardware ecc logic for write */
		this->write_buf(mtd, this->data_poi, mtd->eccsize);
		
		this->calculate_ecc(mtd, NULL, &(ecc_code[0]));
		for (i = 0; i < 3; i++)
			oob_data[oob_config[i]] = ecc_code[i];
			
		if (mtd->oobblock == 512) {
			this->enable_hwecc(mtd, NAND_ECC_WRITE);	/* enable hardware ecc logic for write*/
			this->write_buf(mtd, &this->data_poi[mtd->eccsize], mtd->oobblock - mtd->eccsize);
			this->calculate_ecc(mtd, NULL, &(ecc_code[3]));
			for (i = 3; i < 6; i++)
				oob_data[oob_config[i]] = ecc_code[i];
		}
		break;
				
	/* Hardware ecc 3 byte / 512 byte data, write full page */	
	case NAND_ECC_HW3_512:	
		this->enable_hwecc(mtd, NAND_ECC_WRITE);	/* enable hardware ecc logic */
		this->write_buf(mtd, this->data_poi, mtd->oobblock);
		this->calculate_ecc(mtd, NULL, &(ecc_code[0]));
		for (i = 0; i < 3; i++)
			oob_data[oob_config[i]] = ecc_code[i];
		break;

	/* Hardware ecc 6 byte / 512 byte data, write full page */	
	case NAND_ECC_HW6_512:	
		this->enable_hwecc(mtd, NAND_ECC_WRITE);	/* enable hardware ecc logic */
		this->write_buf(mtd, this->data_poi, mtd->oobblock);
		this->calculate_ecc(mtd, NULL, &(ecc_code[0]));
		for (i = 0; i < 6; i++)
			oob_data[oob_config[i]] = ecc_code[i];
		break;
	
	default:
		printk ("Invalid NAND_ECC_MODE %d\n", this->eccmode);
		return -1;
	}
	
	/* Write out OOB data */
	this->write_buf(mtd, oob_data, mtd->oobsize);

	/* Send command to actually program the data */
	this->cmdfunc (mtd, NAND_CMD_PAGEPROG, -1, -1);

	/* Send command to actually program the data */
	status=this->waitfunc (mtd, this,FL_WRITING);
	
	if(status & 0x01){
//		DEBUG(MTD_DEBUG_LEVEL0,"%S:" "Failed write,page 0x%08x,"__FUNCTION__,page);
		printk("%S:" "Failed write,page 0x%08x,"__FUNCTION__,page);
		return -EIO;
	}	

#ifdef CONFIG_MTD_NAND_VERIFY_WRITE
	/*
	 * The NAND device assumes that it is always writing to
	 * a cleanly erased page. Hence, it performs its internal
	 * write verification only on bits that transitioned from
	 * 1 to 0. The device does NOT verify the whole page on a
	 * byte by byte basis. It is possible that the page was
	 * not completely erased or the page is becoming unusable
	 * due to wear. The read with ECC would catch the error
	 * later when the ECC page check fails, but we would rather
	 * catch it early in the page write stage. Better to write
	 * no data than invalid data.
	 */

	/* Send command to read back the page */
	this->cmdfunc (mtd, NAND_CMD_READ0, 0, page);
	/* Loop through and verify the data */
	if (this->verify_buf(mtd, this->data_poi, mtd->oobblock)) {
//		DEBUG (MTD_DEBUG_LEVEL0, "%s: " "Failed write verify, page 0x%08x ", __FUNCTION__, page);
		printk("%s: " "Failed write verify, page 0x%08x ", __FUNCTION__, page);
		return -EIO;
	}

	/* check, if we have a fs-supplied oob-buffer */
	if (oob_buf) {
		if (this->verify_buf(mtd, oob_data, mtd->oobsize)) {
//			DEBUG (MTD_DEBUG_LEVEL0, "%s: " "Failed write verify, page 0x%08x ", __FUNCTION__, page);
			printk("%s: " "Failed write verify, page 0x%08x ", __FUNCTION__, page);
			return -EIO;
		}
	} else {
		if (eccmode != NAND_ECC_NONE) {
			int ecc_bytes = 0;

			switch (this->eccmode) {
			case NAND_ECC_SOFT:
			case NAND_ECC_HW3_256: ecc_bytes = (mtd->oobblock == 512) ? 6 : 3; break;
			case NAND_ECC_HW3_512: ecc_bytes = 3; break;
			case NAND_ECC_HW6_512: ecc_bytes = 6; break;
			}

			this->read_buf(mtd, oob_data, mtd->oobsize);

			for (i = 0; i < ecc_bytes; i++) {
				if (oob_data[oob_config[i]] != ecc_code[i]) {
//					DEBUG (MTD_DEBUG_LEVEL0,
					printk(									       "%s: Failed ECC write "
				       "verify, page 0x%08x, " "%6i bytes were succesful\n", __FUNCTION__, page, i);
				return -EIO;
				}
			}
		}
	}
#endif
	return 0;
}

/*
*	Use NAND read ECC
*/
static int nand_read (struct mtd_info *mtd, loff_t from, size_t len, size_t * retlen, u_char * buf)
{
	return nand_read_ecc(mtd, from, len, retlen, buf, NULL, NULL);
}			   


/*
 * NAND read with ECC
 */
static int nand_read_ecc (struct mtd_info *mtd, loff_t from, size_t len,
			  size_t * retlen, u_char * buf, u_char * oob_buf, struct nand_oobinfo *oobsel)
{
	int j, col, page, end, ecc;
//	int erase_state = 0;
	int read = 0, oob = 0, ecc_status = 0, ecc_failed = 0;
	struct nand_chip *this = mtd->priv;
	u_char *data_poi, *oob_data = oob_buf;
	u_char ecc_calc[6];
	u_char ecc_code[6];
	int 	eccmode;
	int	*oob_config;

	// use chip default if zero
	if (oobsel == NULL)
		oobsel = &mtd->oobinfo;
		
	eccmode = oobsel->useecc ? this->eccmode : NAND_ECC_NONE;
	oob_config = oobsel->eccpos;

	DEBUG (MTD_DEBUG_LEVEL3, "nand_read_ecc: from = 0x%08x, len = %i\n", (unsigned int) from, (int) len);

	/* Do not allow reads past end of device */
	if ((from + len) > mtd->size) {
//		DEBUG (MTD_DEBUG_LEVEL0, "nand_read_ecc: Attempt read beyond end of device\n");
		printk("nand_read_ecc: Attempt read beyond end of device\n");
		*retlen = 0;
		return -EINVAL;
	}

	/* Select the NAND device */
	this->select_chip(mtd, 0);

	/* First we calculate the starting page */
	page = from >> this->page_shift;

	/* Get raw starting column */
	col = from & (mtd->oobblock - 1);

	end = mtd->oobblock;
	ecc = mtd->eccsize;

	/* Send the read command */
	this->cmdfunc (mtd, NAND_CMD_READ0, 0x00, page);
	
	/* Loop until all data read */
	while (read < len) {
		
		/* If we have consequent page reads, apply delay or wait for ready/busy pin */
		if (read) {
			if (!this->chip_delay) 
				udelay (this->chip_delay);
			else
				while (!this->dev_ready(mtd));	
		}

		/* 
		 * If the read is not page aligned, we have to read into data buffer
		 * due to ecc, else we read into return buffer direct
		 */
		if (!col && (len - read) >= end)  
			data_poi = &buf[read];
		else 
			data_poi = this->data_buf;

		/* get oob area, if we have no oob buffer from fs-driver */
		if (!oob_buf) {
			oob_data = &this->data_buf[end];
			oob = 0;
		} 	
			
		j = 0;
		switch (eccmode) {
		case NAND_ECC_NONE: 	/* No ECC, Read in a page */
			printk ( "Reading data from NAND FLASH without ECC is not recommended\n");			
			this->read_buf(mtd, data_poi, end);
			break;		
			
		case NAND_ECC_SOFT:	/* Software ECC 3/256: Read in a page + oob data */
			this->read_buf(mtd, data_poi, end);
			this->calculate_ecc(mtd, &data_poi[0], &ecc_calc[0]);
			if (mtd->oobblock == 512)
				this->calculate_ecc(mtd, &data_poi[256], &ecc_calc[3]);
			break;	
			
		case NAND_ECC_HW3_256: /* Hardware ECC 3 byte /256 byte data: Read in first 256 byte, get ecc, */
			this->enable_hwecc(mtd, NAND_ECC_READ);	
			this->read_buf(mtd, data_poi, ecc);
			this->calculate_ecc(mtd, &data_poi[0], &ecc_calc[0]);	/* read from hardware */
			
			if (mtd->oobblock == 512) { /* read second, if pagesize = 512 */
				this->enable_hwecc(mtd, NAND_ECC_READ);	
				this->read_buf(mtd, &data_poi[ecc], end-ecc);
				this->calculate_ecc(mtd, &data_poi[256], &ecc_calc[3]); /* read from hardware */
			}					
			break;						
				
		case NAND_ECC_HW3_512:	
		case NAND_ECC_HW6_512: /* Hardware ECC 3/6 byte / 512 byte data : Read in a page  */
			this->enable_hwecc(mtd, NAND_ECC_READ);	
			this->read_buf(mtd, data_poi, end);
			this->calculate_ecc(mtd, &data_poi[0], &ecc_calc[0]);	/* read from hardware */
			break;

		default:
			printk ( "Invalid NAND_ECC_MODE %d\n", this->eccmode);
			return -EIO;
		}

		/* read oobdata */
		for (j = 0; j <  mtd->oobsize; j++) 
			oob_data[oob + j] = this->read_byte(mtd);
		
		/* Skip ECC, if not active */
		if (eccmode == NAND_ECC_NONE)
			goto readdata;	
		
		/* Pick the ECC bytes out of the oob data */
		for (j = 0; j < 6; j++)
			ecc_code[j] = oob_data[oob + oob_config[j]];

		/* correct data, if neccecary */
		ecc_status = this->correct_data(mtd, &data_poi[0], &ecc_code[0], &ecc_calc[0]);
		/* check, if we have a fs supplied oob-buffer */
		if (oob_buf) { 
			oob += mtd->oobsize;
			*((int *)&oob_data[oob]) = ecc_status;
			oob += sizeof(int);
		}
		if (ecc_status == -1) {	
//			DEBUG (MTD_DEBUG_LEVEL0, "nand_read_ecc: " "Failed ECC read, page 0x%08x\n", page);
			printk("nand_read_ecc: " "Failed ECC read, page 0x%08x\n", page);
			ecc_failed++;
		}
		
		if (mtd->oobblock == 512 && eccmode != NAND_ECC_HW3_512) {
			ecc_status = this->correct_data(mtd, &data_poi[256], &ecc_code[3], &ecc_calc[3]);
			if (oob_buf) {
				*((int *)&oob_data[oob]) = ecc_status;
				oob += sizeof(int);
			}