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[MTD] DOC: Fixup read functions and do a little cleanup
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The NAND rework resulted in non ECC based reads. Fix it up and
do a bit of cleanup while at it.

Pointed out by Adrian Bunk.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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Thomas Gleixner committed Jun 28, 2006
1 parent a39727f commit 7f8a894
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Showing 3 changed files with 207 additions and 315 deletions.
179 changes: 73 additions & 106 deletions drivers/mtd/devices/doc2000.c
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Original file line number Diff line number Diff line change
Expand Up @@ -55,10 +55,6 @@ 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,
struct mtd_oob_ops *ops);
static int doc_write_oob(struct mtd_info *mtd, loff_t ofs,
Expand Down Expand Up @@ -614,18 +610,11 @@ EXPORT_SYMBOL_GPL(DoC2k_init);

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, 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 nand_oobinfo *oobsel)
{
struct DiskOnChip *this = mtd->priv;
void __iomem *docptr = this->virtadr;
struct Nand *mychip;
unsigned char syndrome[6];
unsigned char syndrome[6], eccbuf[6];
volatile char dummy;
int i, len256 = 0, ret=0;
size_t left = len;
Expand Down Expand Up @@ -673,15 +662,9 @@ static int doc_read_ecc(struct mtd_info *mtd, loff_t from, size_t len,
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);
}
/* Prime the ECC engine */
WriteDOC(DOC_ECC_RESET, docptr, ECCConf);
WriteDOC(DOC_ECC_EN, docptr, ECCConf);

/* treat crossing 256-byte sector for 2M x 8bits devices */
if (this->page256 && from + len > (from | 0xff) + 1) {
Expand All @@ -698,58 +681,59 @@ static int doc_read_ecc(struct mtd_info *mtd, loff_t from, size_t len,
/* 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);
}
/* 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);

/* Check the ECC Status */
if (i & 0x80) {
int nb_errors;
/* There was an ECC error */
/* 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);
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);
/* 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);
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;
}
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]);
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);
}
/* 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. */
Expand All @@ -770,18 +754,11 @@ static int doc_read_ecc(struct mtd_info *mtd, loff_t from, size_t len,

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, NULL);
}

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)
{
struct DiskOnChip *this = mtd->priv;
int di; /* Yes, DI is a hangover from when I was disassembling the binary driver */
void __iomem *docptr = this->virtadr;
unsigned char eccbuf[6];
volatile char dummy;
int len256 = 0;
struct Nand *mychip;
Expand Down Expand Up @@ -835,15 +812,9 @@ static int doc_write_ecc(struct mtd_info *mtd, loff_t to, size_t len,
DoC_Command(this, NAND_CMD_SEQIN, 0);
DoC_Address(this, ADDR_COLUMN_PAGE, to, 0, CDSN_CTRL_ECC_IO);

if (eccbuf) {
/* Prime the ECC engine */
WriteDOC(DOC_ECC_RESET, docptr, ECCConf);
WriteDOC(DOC_ECC_EN | DOC_ECC_RW, docptr, ECCConf);
} else {
/* disable the ECC engine */
WriteDOC(DOC_ECC_RESET, docptr, ECCConf);
WriteDOC(DOC_ECC_DIS, docptr, ECCConf);
}
/* 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) {
Expand Down Expand Up @@ -873,39 +844,35 @@ static int doc_write_ecc(struct mtd_info *mtd, loff_t to, size_t len,

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

if (eccbuf) {
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_CE, docptr, CDSNControl);

WriteDOC(CDSN_CTRL_ECC_IO | CDSN_CTRL_FLASH_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);
}

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

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