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u-boot/drivers/mtd/nand_legacy/nand_legacy.c

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/*
* (C) 2006 Denx
* Driver for NAND support, Rick Bronson
* borrowed heavily from:
* (c) 1999 Machine Vision Holdings, Inc.
* (c) 1999, 2000 David Woodhouse <dwmw2@infradead.org>
*
* Added 16-bit nand support
* (C) 2004 Texas Instruments
*/
#include <common.h>
#include <command.h>
#include <malloc.h>
#include <asm/io.h>
#include <watchdog.h>
#include <linux/mtd/nand_legacy.h>
#include <linux/mtd/nand_ids.h>
#include <jffs2/jffs2.h>
#error Legacy NAND is deprecated. Please convert to the current NAND interface.
#error This code will be removed outright in the next release.
#ifdef CONFIG_OMAP1510
void archflashwp(void *archdata, int wp);
#endif
#define ROUND_DOWN(value,boundary) ((value) & (~((boundary)-1)))
#undef PSYCHO_DEBUG
#undef NAND_DEBUG
/* ****************** WARNING *********************
* When ALLOW_ERASE_BAD_DEBUG is non-zero the erase command will
* erase (or at least attempt to erase) blocks that are marked
* bad. This can be very handy if you are _sure_ that the block
* is OK, say because you marked a good block bad to test bad
* block handling and you are done testing, or if you have
* accidentally marked blocks bad.
*
* Erasing factory marked bad blocks is a _bad_ idea. If the
* erase succeeds there is no reliable way to find them again,
* and attempting to program or erase bad blocks can affect
* the data in _other_ (good) blocks.
*/
#define ALLOW_ERASE_BAD_DEBUG 0
#define CONFIG_MTD_NAND_ECC /* enable ECC */
#define CONFIG_MTD_NAND_ECC_JFFS2
/* bits for nand_legacy_rw() `cmd'; or together as needed */
#define NANDRW_READ 0x01
#define NANDRW_WRITE 0x00
#define NANDRW_JFFS2 0x02
#define NANDRW_JFFS2_SKIP 0x04
/*
* Exported variables etc.
*/
/* Definition of the out of band configuration structure */
struct nand_oob_config {
/* position of ECC bytes inside oob */
int ecc_pos[6];
/* position of bad blk flag inside oob -1 = inactive */
int badblock_pos;
/* position of ECC valid flag inside oob -1 = inactive */
int eccvalid_pos;
} oob_config = { {0}, 0, 0};
struct nand_chip nand_dev_desc[CONFIG_SYS_MAX_NAND_DEVICE] = {{0}};
int curr_device = -1; /* Current NAND Device */
/*
* Exported functionss
*/
int nand_legacy_erase(struct nand_chip* nand, size_t ofs,
size_t len, int clean);
int nand_legacy_rw(struct nand_chip* nand, int cmd,
size_t start, size_t len,
size_t * retlen, u_char * buf);
void nand_print(struct nand_chip *nand);
void nand_print_bad(struct nand_chip *nand);
int nand_read_oob(struct nand_chip* nand, size_t ofs, size_t len,
size_t * retlen, u_char * buf);
int nand_write_oob(struct nand_chip* nand, size_t ofs, size_t len,
size_t * retlen, const u_char * buf);
/*
* Internals
*/
static int NanD_WaitReady(struct nand_chip *nand, int ale_wait);
static int nand_read_ecc(struct nand_chip *nand, size_t start, size_t len,
size_t * retlen, u_char *buf, u_char *ecc_code);
static int nand_write_ecc (struct nand_chip* nand, size_t to, size_t len,
size_t * retlen, const u_char * buf,
u_char * ecc_code);
#ifdef CONFIG_MTD_NAND_ECC
static int nand_correct_data (u_char *dat, u_char *read_ecc, u_char *calc_ecc);
static void nand_calculate_ecc (const u_char *dat, u_char *ecc_code);
#endif
/*
*
* Function definitions
*
*/
/* returns 0 if block containing pos is OK:
* valid erase block and
* not marked bad, or no bad mark position is specified
* returns 1 if marked bad or otherwise invalid
*/
static int check_block (struct nand_chip *nand, unsigned long pos)
{
size_t retlen;
uint8_t oob_data;
uint16_t oob_data16[6];
int page0 = pos & (-nand->erasesize);
int page1 = page0 + nand->oobblock;
int badpos = oob_config.badblock_pos;
if (pos >= nand->totlen)
return 1;
if (badpos < 0)
return 0; /* no way to check, assume OK */
if (nand->bus16) {
if (nand_read_oob(nand, (page0 + 0), 12, &retlen, (uint8_t *)oob_data16)
|| (oob_data16[2] & 0xff00) != 0xff00)
return 1;
if (nand_read_oob(nand, (page1 + 0), 12, &retlen, (uint8_t *)oob_data16)
|| (oob_data16[2] & 0xff00) != 0xff00)
return 1;
} else {
/* Note - bad block marker can be on first or second page */
if (nand_read_oob(nand, page0 + badpos, 1, &retlen, (unsigned char *)&oob_data)
|| oob_data != 0xff
|| nand_read_oob (nand, page1 + badpos, 1, &retlen, (unsigned char *)&oob_data)
|| oob_data != 0xff)
return 1;
}
return 0;
}
/* print bad blocks in NAND flash */
void nand_print_bad(struct nand_chip* nand)
{
unsigned long pos;
for (pos = 0; pos < nand->totlen; pos += nand->erasesize) {
if (check_block(nand, pos))
printf(" 0x%8.8lx\n", pos);
}
puts("\n");
}
/* cmd: 0: NANDRW_WRITE write, fail on bad block
* 1: NANDRW_READ read, fail on bad block
* 2: NANDRW_WRITE | NANDRW_JFFS2 write, skip bad blocks
* 3: NANDRW_READ | NANDRW_JFFS2 read, data all 0xff for bad blocks
* 7: NANDRW_READ | NANDRW_JFFS2 | NANDRW_JFFS2_SKIP read, skip bad blocks
*/
int nand_legacy_rw (struct nand_chip* nand, int cmd,
size_t start, size_t len,
size_t * retlen, u_char * buf)
{
int ret = 0, n, total = 0;
char eccbuf[6];
/* eblk (once set) is the start of the erase block containing the
* data being processed.
*/
unsigned long eblk = ~0; /* force mismatch on first pass */
unsigned long erasesize = nand->erasesize;
while (len) {
if ((start & (-erasesize)) != eblk) {
/* have crossed into new erase block, deal with
* it if it is sure marked bad.
*/
eblk = start & (-erasesize); /* start of block */
if (check_block(nand, eblk)) {
if (cmd == (NANDRW_READ | NANDRW_JFFS2)) {
while (len > 0 &&
start - eblk < erasesize) {
*(buf++) = 0xff;
++start;
++total;
--len;
}
continue;
} else if (cmd == (NANDRW_READ | NANDRW_JFFS2 | NANDRW_JFFS2_SKIP)) {
start += erasesize;
continue;
} else if (cmd == (NANDRW_WRITE | NANDRW_JFFS2)) {
/* skip bad block */
start += erasesize;
continue;
} else {
ret = 1;
break;
}
}
}
/* The ECC will not be calculated correctly if
less than 512 is written or read */
/* Is request at least 512 bytes AND it starts on a proper boundry */
if((start != ROUND_DOWN(start, 0x200)) || (len < 0x200))
printf("Warning block writes should be at least 512 bytes and start on a 512 byte boundry\n");
if (cmd & NANDRW_READ) {
ret = nand_read_ecc(nand, start,
min(len, eblk + erasesize - start),
(size_t *)&n, (u_char*)buf, (u_char *)eccbuf);
} else {
ret = nand_write_ecc(nand, start,
min(len, eblk + erasesize - start),
(size_t *)&n, (u_char*)buf, (u_char *)eccbuf);
}
if (ret)
break;
start += n;
buf += n;
total += n;
len -= n;
}
if (retlen)
*retlen = total;
return ret;
}
void nand_print(struct nand_chip *nand)
{
if (nand->numchips > 1) {
printf("%s at 0x%lx,\n"
"\t %d chips %s, size %d MB, \n"
"\t total size %ld MB, sector size %ld kB\n",
nand->name, nand->IO_ADDR, nand->numchips,
nand->chips_name, 1 << (nand->chipshift - 20),
nand->totlen >> 20, nand->erasesize >> 10);
}
else {
printf("%s at 0x%lx (", nand->chips_name, nand->IO_ADDR);
print_size(nand->totlen, ", ");
print_size(nand->erasesize, " sector)\n");
}
}
/* ------------------------------------------------------------------------- */
static int NanD_WaitReady(struct nand_chip *nand, int ale_wait)
{
/* This is inline, to optimise the common case, where it's ready instantly */
int ret = 0;
#ifdef NAND_NO_RB /* in config file, shorter delays currently wrap accesses */
if(ale_wait)
NAND_WAIT_READY(nand); /* do the worst case 25us wait */
else
udelay(10);
#else /* has functional r/b signal */
NAND_WAIT_READY(nand);
#endif
return ret;
}
/* NanD_Command: Send a flash command to the flash chip */
static inline int NanD_Command(struct nand_chip *nand, unsigned char command)
{
unsigned long nandptr = nand->IO_ADDR;
/* Assert the CLE (Command Latch Enable) line to the flash chip */
NAND_CTL_SETCLE(nandptr);
/* Send the command */
WRITE_NAND_COMMAND(command, nandptr);
/* Lower the CLE line */
NAND_CTL_CLRCLE(nandptr);
#ifdef NAND_NO_RB
if(command == NAND_CMD_RESET){
u_char ret_val;
NanD_Command(nand, NAND_CMD_STATUS);
do {
ret_val = READ_NAND(nandptr);/* wait till ready */
} while((ret_val & 0x40) != 0x40);
}
#endif
return NanD_WaitReady(nand, 0);
}
/* NanD_Address: Set the current address for the flash chip */
static int NanD_Address(struct nand_chip *nand, int numbytes, unsigned long ofs)
{
unsigned long nandptr;
int i;
nandptr = nand->IO_ADDR;
/* Assert the ALE (Address Latch Enable) line to the flash chip */
NAND_CTL_SETALE(nandptr);
/* Send the address */
/* Devices with 256-byte page are addressed as:
* Column (bits 0-7), Page (bits 8-15, 16-23, 24-31)
* there is no device on the market with page256
* and more than 24 bits.
* Devices with 512-byte page are addressed as:
* Column (bits 0-7), Page (bits 9-16, 17-24, 25-31)
* 25-31 is sent only if the chip support it.
* bit 8 changes the read command to be sent
* (NAND_CMD_READ0 or NAND_CMD_READ1).
*/
if (numbytes == ADDR_COLUMN || numbytes == ADDR_COLUMN_PAGE)
WRITE_NAND_ADDRESS(ofs, nandptr);
ofs = ofs >> nand->page_shift;
if (numbytes == ADDR_PAGE || numbytes == ADDR_COLUMN_PAGE) {
for (i = 0; i < nand->pageadrlen; i++, ofs = ofs >> 8) {
WRITE_NAND_ADDRESS(ofs, nandptr);
}
}
/* Lower the ALE line */
NAND_CTL_CLRALE(nandptr);
/* Wait for the chip to respond */
return NanD_WaitReady(nand, 1);
}
/* NanD_SelectChip: Select a given flash chip within the current floor */
static inline int NanD_SelectChip(struct nand_chip *nand, int chip)
{
/* Wait for it to be ready */
return NanD_WaitReady(nand, 0);
}
/* NanD_IdentChip: Identify a given NAND chip given {floor,chip} */
static int NanD_IdentChip(struct nand_chip *nand, int floor, int chip)
{
int mfr, id, i;
NAND_ENABLE_CE(nand); /* set pin low */
/* Reset the chip */
if (NanD_Command(nand, NAND_CMD_RESET)) {
#ifdef NAND_DEBUG
printf("NanD_Command (reset) for %d,%d returned true\n",
floor, chip);
#endif
NAND_DISABLE_CE(nand); /* set pin high */
return 0;
}
/* Read the NAND chip ID: 1. Send ReadID command */
if (NanD_Command(nand, NAND_CMD_READID)) {
#ifdef NAND_DEBUG
printf("NanD_Command (ReadID) for %d,%d returned true\n",
floor, chip);
#endif
NAND_DISABLE_CE(nand); /* set pin high */
return 0;
}
/* Read the NAND chip ID: 2. Send address byte zero */
NanD_Address(nand, ADDR_COLUMN, 0);
/* Read the manufacturer and device id codes from the device */
mfr = READ_NAND(nand->IO_ADDR);
id = READ_NAND(nand->IO_ADDR);
NAND_DISABLE_CE(nand); /* set pin high */
#ifdef NAND_DEBUG
printf("NanD_Command (ReadID) got %x %x\n", mfr, id);
#endif
if (mfr == 0xff || mfr == 0) {
/* No response - return failure */
return 0;
}
/* Check it's the same as the first chip we identified.
* M-Systems say that any given nand_chip device should only
* contain _one_ type of flash part, although that's not a
* hardware restriction. */
if (nand->mfr) {
if (nand->mfr == mfr && nand->id == id) {
return 1; /* This is another the same the first */
} else {
printf("Flash chip at floor %d, chip %d is different:\n",
floor, chip);
}
}
/* Print and store the manufacturer and ID codes. */
for (i = 0; nand_flash_ids[i].name != NULL; i++) {
if (mfr == nand_flash_ids[i].manufacture_id &&
id == nand_flash_ids[i].model_id) {
#ifdef NAND_DEBUG
printf("Flash chip found:\n\t Manufacturer ID: 0x%2.2X, "
"Chip ID: 0x%2.2X (%s)\n", mfr, id,
nand_flash_ids[i].name);
#endif
if (!nand->mfr) {
nand->mfr = mfr;
nand->id = id;
nand->chipshift =
nand_flash_ids[i].chipshift;
nand->page256 = nand_flash_ids[i].page256;
nand->eccsize = 256;
if (nand->page256) {
nand->oobblock = 256;
nand->oobsize = 8;
nand->page_shift = 8;
} else {
nand->oobblock = 512;
nand->oobsize = 16;
nand->page_shift = 9;
}
nand->pageadrlen = nand_flash_ids[i].pageadrlen;
nand->erasesize = nand_flash_ids[i].erasesize;
nand->chips_name = nand_flash_ids[i].name;
nand->bus16 = nand_flash_ids[i].bus16;
return 1;
}
return 0;
}
}
#ifdef NAND_DEBUG
/* We haven't fully identified the chip. Print as much as we know. */
printf("Unknown flash chip found: %2.2X %2.2X\n",
id, mfr);
#endif
return 0;
}
/* NanD_ScanChips: Find all NAND chips present in a nand_chip, and identify them */
static void NanD_ScanChips(struct nand_chip *nand)
{
int floor, chip;
int numchips[NAND_MAX_FLOORS];
int maxchips = CONFIG_SYS_NAND_MAX_CHIPS;
int ret = 1;
nand->numchips = 0;
nand->mfr = 0;
nand->id = 0;
/* For each floor, find the number of valid chips it contains */
for (floor = 0; floor < NAND_MAX_FLOORS; floor++) {
ret = 1;
numchips[floor] = 0;
for (chip = 0; chip < maxchips && ret != 0; chip++) {
ret = NanD_IdentChip(nand, floor, chip);
if (ret) {
numchips[floor]++;
nand->numchips++;
}
}
}
/* If there are none at all that we recognise, bail */
if (!nand->numchips) {
#ifdef NAND_DEBUG
puts ("No NAND flash chips recognised.\n");
#endif
return;
}
/* Allocate an array to hold the information for each chip */
nand->chips = malloc(sizeof(struct Nand) * nand->numchips);
if (!nand->chips) {
puts ("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 < NAND_MAX_FLOORS; floor++) {
for (chip = 0; chip < numchips[floor]; chip++) {
nand->chips[ret].floor = floor;
nand->chips[ret].chip = chip;
nand->chips[ret].curadr = 0;
nand->chips[ret].curmode = 0x50;
ret++;
}
}
/* Calculate and print the total size of the device */
nand->totlen = nand->numchips * (1 << nand->chipshift);
#ifdef NAND_DEBUG
printf("%d flash chips found. Total nand_chip size: %ld MB\n",
nand->numchips, nand->totlen >> 20);
#endif
}
/* we need to be fast here, 1 us per read translates to 1 second per meg */
static void NanD_ReadBuf (struct nand_chip *nand, u_char * data_buf, int cntr)
{
unsigned long nandptr = nand->IO_ADDR;
NanD_Command (nand, NAND_CMD_READ0);
if (nand->bus16) {
u16 val;
while (cntr >= 16) {
val = READ_NAND (nandptr);
*data_buf++ = val & 0xff;
*data_buf++ = val >> 8;
val = READ_NAND (nandptr);
*data_buf++ = val & 0xff;
*data_buf++ = val >> 8;
val = READ_NAND (nandptr);
*data_buf++ = val & 0xff;
*data_buf++ = val >> 8;
val = READ_NAND (nandptr);
*data_buf++ = val & 0xff;
*data_buf++ = val >> 8;
val = READ_NAND (nandptr);
*data_buf++ = val & 0xff;
*data_buf++ = val >> 8;
val = READ_NAND (nandptr);
*data_buf++ = val & 0xff;
*data_buf++ = val >> 8;
val = READ_NAND (nandptr);
*data_buf++ = val & 0xff;
*data_buf++ = val >> 8;
val = READ_NAND (nandptr);
*data_buf++ = val & 0xff;
*data_buf++ = val >> 8;
cntr -= 16;
}
while (cntr > 0) {
val = READ_NAND (nandptr);
*data_buf++ = val & 0xff;
*data_buf++ = val >> 8;
cntr -= 2;
}
} else {
while (cntr >= 16) {
*data_buf++ = READ_NAND (nandptr);
*data_buf++ = READ_NAND (nandptr);
*data_buf++ = READ_NAND (nandptr);
*data_buf++ = READ_NAND (nandptr);
*data_buf++ = READ_NAND (nandptr);
*data_buf++ = READ_NAND (nandptr);
*data_buf++ = READ_NAND (nandptr);
*data_buf++ = READ_NAND (nandptr);
*data_buf++ = READ_NAND (nandptr);
*data_buf++ = READ_NAND (nandptr);
*data_buf++ = READ_NAND (nandptr);
*data_buf++ = READ_NAND (nandptr);
*data_buf++ = READ_NAND (nandptr);
*data_buf++ = READ_NAND (nandptr);
*data_buf++ = READ_NAND (nandptr);
*data_buf++ = READ_NAND (nandptr);
cntr -= 16;
}
while (cntr > 0) {
*data_buf++ = READ_NAND (nandptr);
cntr--;
}
}
}
/*
* NAND read with ECC
*/
static int nand_read_ecc(struct nand_chip *nand, size_t start, size_t len,
size_t * retlen, u_char *buf, u_char *ecc_code)
{
int col, page;
int ecc_status = 0;
#ifdef CONFIG_MTD_NAND_ECC
int j;
int ecc_failed = 0;
u_char *data_poi;
u_char ecc_calc[6];
#endif
/* Do not allow reads past end of device */
if ((start + len) > nand->totlen) {
printf ("%s: Attempt read beyond end of device %x %x %x\n",
__FUNCTION__, (uint) start, (uint) len, (uint) nand->totlen);
*retlen = 0;
return -1;
}
/* First we calculate the starting page */
/*page = shr(start, nand->page_shift);*/
page = start >> nand->page_shift;
/* Get raw starting column */
col = start & (nand->oobblock - 1);
/* Initialize return value */
*retlen = 0;
/* Select the NAND device */
NAND_ENABLE_CE(nand); /* set pin low */
/* Loop until all data read */
while (*retlen < len) {
#ifdef CONFIG_MTD_NAND_ECC
/* Do we have this page in cache ? */
if (nand->cache_page == page)
goto readdata;
/* Send the read command */
NanD_Command(nand, NAND_CMD_READ0);
if (nand->bus16) {
NanD_Address(nand, ADDR_COLUMN_PAGE,
(page << nand->page_shift) + (col >> 1));
} else {
NanD_Address(nand, ADDR_COLUMN_PAGE,
(page << nand->page_shift) + col);
}
/* Read in a page + oob data */
NanD_ReadBuf(nand, nand->data_buf, nand->oobblock + nand->oobsize);
/* copy data into cache, for read out of cache and if ecc fails */
if (nand->data_cache) {
memcpy (nand->data_cache, nand->data_buf,
nand->oobblock + nand->oobsize);
}
/* Pick the ECC bytes out of the oob data */
for (j = 0; j < 6; j++) {
ecc_code[j] = nand->data_buf[(nand->oobblock + oob_config.ecc_pos[j])];
}
/* Calculate the ECC and verify it */
/* If block was not written with ECC, skip ECC */
if (oob_config.eccvalid_pos != -1 &&
(nand->data_buf[nand->oobblock + oob_config.eccvalid_pos] & 0x0f) != 0x0f) {
nand_calculate_ecc (&nand->data_buf[0], &ecc_calc[0]);
switch (nand_correct_data (&nand->data_buf[0], &ecc_code[0], &ecc_calc[0])) {
case -1:
printf ("%s: Failed ECC read, page 0x%08x\n", __FUNCTION__, page);
ecc_failed++;
break;
case 1:
case 2: /* transfer ECC corrected data to cache */
if (nand->data_cache)
memcpy (nand->data_cache, nand->data_buf, 256);
break;
}
}
if (oob_config.eccvalid_pos != -1 &&
nand->oobblock == 512 && (nand->data_buf[nand->oobblock + oob_config.eccvalid_pos] & 0xf0) != 0xf0) {
nand_calculate_ecc (&nand->data_buf[256], &ecc_calc[3]);
switch (nand_correct_data (&nand->data_buf[256], &ecc_code[3], &ecc_calc[3])) {
case -1:
printf ("%s: Failed ECC read, page 0x%08x\n", __FUNCTION__, page);
ecc_failed++;
break;
case 1:
case 2: /* transfer ECC corrected data to cache */
if (nand->data_cache)
memcpy (&nand->data_cache[256], &nand->data_buf[256], 256);
break;
}
}
readdata:
/* Read the data from ECC data buffer into return buffer */
data_poi = (nand->data_cache) ? nand->data_cache : nand->data_buf;
data_poi += col;
if ((*retlen + (nand->oobblock - col)) >= len) {
memcpy (buf + *retlen, data_poi, len - *retlen);
*retlen = len;
} else {
memcpy (buf + *retlen, data_poi, nand->oobblock - col);
*retlen += nand->oobblock - col;
}
/* Set cache page address, invalidate, if ecc_failed */
nand->cache_page = (nand->data_cache && !ecc_failed) ? page : -1;
ecc_status += ecc_failed;
ecc_failed = 0;
#else
/* Send the read command */
NanD_Command(nand, NAND_CMD_READ0);
if (nand->bus16) {
NanD_Address(nand, ADDR_COLUMN_PAGE,
(page << nand->page_shift) + (col >> 1));
} else {
NanD_Address(nand, ADDR_COLUMN_PAGE,
(page << nand->page_shift) + col);
}
/* Read the data directly into the return buffer */
if ((*retlen + (nand->oobblock - col)) >= len) {
NanD_ReadBuf(nand, buf + *retlen, len - *retlen);
*retlen = len;
/* We're done */
continue;
} else {
NanD_ReadBuf(nand, buf + *retlen, nand->oobblock - col);
*retlen += nand->oobblock - col;
}
#endif
/* For subsequent reads align to page boundary. */
col = 0;
/* Increment page address */
page++;
}
/* De-select the NAND device */
NAND_DISABLE_CE(nand); /* set pin high */
/*
* Return success, if no ECC failures, else -EIO
* fs driver will take care of that, because
* retlen == desired len and result == -EIO
*/
return ecc_status ? -1 : 0;
}
/*
* Nand_page_program function is used for write and writev !
*/
static int nand_write_page (struct nand_chip *nand,
int page, int col, int last, u_char * ecc_code)
{
int i;
unsigned long nandptr = nand->IO_ADDR;
#ifdef CONFIG_MTD_NAND_ECC
#ifdef CONFIG_MTD_NAND_VERIFY_WRITE
int ecc_bytes = (nand->oobblock == 512) ? 6 : 3;
#endif
#endif
/* pad oob area */
for (i = nand->oobblock; i < nand->oobblock + nand->oobsize; i++)
nand->data_buf[i] = 0xff;
#ifdef CONFIG_MTD_NAND_ECC
/* Zero out the ECC array */
for (i = 0; i < 6; i++)
ecc_code[i] = 0x00;
/* Read back previous written data, if col > 0 */
if (col) {
NanD_Command (nand, NAND_CMD_READ0);
if (nand->bus16) {
NanD_Address (nand, ADDR_COLUMN_PAGE,
(page << nand->page_shift) + (col >> 1));
} else {
NanD_Address (nand, ADDR_COLUMN_PAGE,
(page << nand->page_shift) + col);
}
if (nand->bus16) {
u16 val;
for (i = 0; i < col; i += 2) {
val = READ_NAND (nandptr);
nand->data_buf[i] = val & 0xff;
nand->data_buf[i + 1] = val >> 8;
}
} else {
for (i = 0; i < col; i++)
nand->data_buf[i] = READ_NAND (nandptr);
}
}
/* Calculate and write the ECC if we have enough data */
if ((col < nand->eccsize) && (last >= nand->eccsize)) {
nand_calculate_ecc (&nand->data_buf[0], &(ecc_code[0]));
for (i = 0; i < 3; i++) {
nand->data_buf[(nand->oobblock +
oob_config.ecc_pos[i])] = ecc_code[i];
}
if (oob_config.eccvalid_pos != -1) {
nand->data_buf[nand->oobblock +
oob_config.eccvalid_pos] = 0xf0;
}
}
/* Calculate and write the second ECC if we have enough data */
if ((nand->oobblock == 512) && (last == nand->oobblock)) {
nand_calculate_ecc (&nand->data_buf[256], &(ecc_code[3]));
for (i = 3; i < 6; i++) {
nand->data_buf[(nand->oobblock +
oob_config.ecc_pos[i])] = ecc_code[i];
}
if (oob_config.eccvalid_pos != -1) {
nand->data_buf[nand->oobblock +
oob_config.eccvalid_pos] &= 0x0f;
}
}
#endif
/* Prepad for partial page programming !!! */
for (i = 0; i < col; i++)
nand->data_buf[i] = 0xff;
/* Postpad for partial page programming !!! oob is already padded */
for (i = last; i < nand->oobblock; i++)
nand->data_buf[i] = 0xff;
/* Send command to begin auto page programming */
NanD_Command (nand, NAND_CMD_READ0);
NanD_Command (nand, NAND_CMD_SEQIN);
if (nand->bus16) {
NanD_Address (nand, ADDR_COLUMN_PAGE,
(page << nand->page_shift) + (col >> 1));
} else {
NanD_Address (nand, ADDR_COLUMN_PAGE,
(page << nand->page_shift) + col);
}
/* Write out complete page of data */
if (nand->bus16) {
for (i = 0; i < (nand->oobblock + nand->oobsize); i += 2) {
WRITE_NAND (nand->data_buf[i] +
(nand->data_buf[i + 1] << 8),
nand->IO_ADDR);
}
} else {
for (i = 0; i < (nand->oobblock + nand->oobsize); i++)
WRITE_NAND (nand->data_buf[i], nand->IO_ADDR);
}
/* Send command to actually program the data */
NanD_Command (nand, NAND_CMD_PAGEPROG);
NanD_Command (nand, NAND_CMD_STATUS);
#ifdef NAND_NO_RB
{
u_char ret_val;
do {
ret_val = READ_NAND (nandptr); /* wait till ready */
} while ((ret_val & 0x40) != 0x40);
}
#endif
/* See if device thinks it succeeded */
if (READ_NAND (nand->IO_ADDR) & 0x01) {
printf ("%s: Failed write, page 0x%08x, ", __FUNCTION__,
page);
return -1;
}
#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 */
if (col < nand->eccsize)
NanD_Command (nand, NAND_CMD_READ0);
else
NanD_Command (nand, NAND_CMD_READ1);
if (nand->bus16) {
NanD_Address (nand, ADDR_COLUMN_PAGE,
(page << nand->page_shift) + (col >> 1));
} else {
NanD_Address (nand, ADDR_COLUMN_PAGE,
(page << nand->page_shift) + col);
}
/* Loop through and verify the data */
if (nand->bus16) {
for (i = col; i < last; i = +2) {
if ((nand->data_buf[i] +
(nand->data_buf[i + 1] << 8)) != READ_NAND (nand->IO_ADDR)) {
printf ("%s: Failed write verify, page 0x%08x ",
__FUNCTION__, page);
return -1;
}
}
} else {
for (i = col; i < last; i++) {
if (nand->data_buf[i] != READ_NAND (nand->IO_ADDR)) {
printf ("%s: Failed write verify, page 0x%08x ",
__FUNCTION__, page);
return -1;
}
}
}
#ifdef CONFIG_MTD_NAND_ECC
/*
* We also want to check that the ECC bytes wrote
* correctly for the same reasons stated above.
*/
NanD_Command (nand, NAND_CMD_READOOB);
if (nand->bus16) {
NanD_Address (nand, ADDR_COLUMN_PAGE,
(page << nand->page_shift) + (col >> 1));
} else {
NanD_Address (nand, ADDR_COLUMN_PAGE,
(page << nand->page_shift) + col);
}
if (nand->bus16) {
for (i = 0; i < nand->oobsize; i += 2) {
u16 val;
val = READ_NAND (nand->IO_ADDR);
nand->data_buf[i] = val & 0xff;
nand->data_buf[i + 1] = val >> 8;
}
} else {
for (i = 0; i < nand->oobsize; i++) {
nand->data_buf[i] = READ_NAND (nand->IO_ADDR);
}
}
for (i = 0; i < ecc_bytes; i++) {
if ((nand->data_buf[(oob_config.ecc_pos[i])] != ecc_code[i]) && ecc_code[i]) {
printf ("%s: Failed ECC write "
"verify, page 0x%08x, "
"%6i bytes were succesful\n",
__FUNCTION__, page, i);
return -1;
}
}
#endif /* CONFIG_MTD_NAND_ECC */
#endif /* CONFIG_MTD_NAND_VERIFY_WRITE */
return 0;
}
static int nand_write_ecc (struct nand_chip* nand, size_t to, size_t len,
size_t * retlen, const u_char * buf, u_char * ecc_code)
{
int i, page, col, cnt, ret = 0;
/* Do not allow write past end of device */
if ((to + len) > nand->totlen) {
printf ("%s: Attempt to write past end of page\n", __FUNCTION__);
return -1;
}
/* Shift to get page */
page = ((int) to) >> nand->page_shift;
/* Get the starting column */
col = to & (nand->oobblock - 1);
/* Initialize return length value */
*retlen = 0;
/* Select the NAND device */
#ifdef CONFIG_OMAP1510
archflashwp(0,0);
#endif
#ifdef CONFIG_SYS_NAND_WP
NAND_WP_OFF();
#endif
NAND_ENABLE_CE(nand); /* set pin low */
/* Check the WP bit */
NanD_Command(nand, NAND_CMD_STATUS);
if (!(READ_NAND(nand->IO_ADDR) & 0x80)) {
printf ("%s: Device is write protected!!!\n", __FUNCTION__);
ret = -1;
goto out;
}
/* Loop until all data is written */
while (*retlen < len) {
/* Invalidate cache, if we write to this page */
if (nand->cache_page == page)
nand->cache_page = -1;
/* Write data into buffer */
if ((col + len) >= nand->oobblock) {
for (i = col, cnt = 0; i < nand->oobblock; i++, cnt++) {
nand->data_buf[i] = buf[(*retlen + cnt)];
}
} else {
for (i = col, cnt = 0; cnt < (len - *retlen); i++, cnt++) {
nand->data_buf[i] = buf[(*retlen + cnt)];
}
}
/* We use the same function for write and writev !) */
ret = nand_write_page (nand, page, col, i, ecc_code);
if (ret)
goto out;
/* Next data start at page boundary */
col = 0;
/* Update written bytes count */
*retlen += cnt;
/* Increment page address */
page++;
}
/* Return happy */
*retlen = len;
out:
/* De-select the NAND device */
NAND_DISABLE_CE(nand); /* set pin high */
#ifdef CONFIG_OMAP1510
archflashwp(0,1);
#endif
#ifdef CONFIG_SYS_NAND_WP
NAND_WP_ON();
#endif
return ret;
}
/* read from the 16 bytes of oob data that correspond to a 512 byte
* page or 2 256-byte pages.
*/
int nand_read_oob(struct nand_chip* nand, size_t ofs, size_t len,
size_t * retlen, u_char * buf)
{
int len256 = 0;
struct Nand *mychip;
int ret = 0;
mychip = &nand->chips[ofs >> nand->chipshift];
/* update address for 2M x 8bit devices. OOB starts on the second */
/* page to maintain compatibility with nand_read_ecc. */
if (nand->page256) {
if (!(ofs & 0x8))
ofs += 0x100;
else
ofs -= 0x8;
}
NAND_ENABLE_CE(nand); /* set pin low */
NanD_Command(nand, NAND_CMD_READOOB);
if (nand->bus16) {
NanD_Address(nand, ADDR_COLUMN_PAGE,
((ofs >> nand->page_shift) << nand->page_shift) +
((ofs & (nand->oobblock - 1)) >> 1));
} else {
NanD_Address(nand, ADDR_COLUMN_PAGE, ofs);
}
/* 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 (nand->page256 && ofs + len > (ofs | 0x7) + 1) {
len256 = (ofs | 0x7) + 1 - ofs;
NanD_ReadBuf(nand, buf, len256);
NanD_Command(nand, NAND_CMD_READOOB);
NanD_Address(nand, ADDR_COLUMN_PAGE, ofs & (~0x1ff));
}
NanD_ReadBuf(nand, &buf[len256], len - len256);
*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 nands */
ret = NanD_WaitReady(nand, 1);
NAND_DISABLE_CE(nand); /* set pin high */
return ret;
}
/* write to the 16 bytes of oob data that correspond to a 512 byte
* page or 2 256-byte pages.
*/
int nand_write_oob(struct nand_chip* nand, size_t ofs, size_t len,
size_t * retlen, const u_char * buf)
{
int len256 = 0;
int i;
unsigned long nandptr = nand->IO_ADDR;
#ifdef PSYCHO_DEBUG
printf("nand_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]);
#endif
NAND_ENABLE_CE(nand); /* set pin low to enable chip */
/* Reset the chip */
NanD_Command(nand, NAND_CMD_RESET);
/* issue the Read2 command to set the pointer to the Spare Data Area. */
NanD_Command(nand, NAND_CMD_READOOB);
if (nand->bus16) {
NanD_Address(nand, ADDR_COLUMN_PAGE,
((ofs >> nand->page_shift) << nand->page_shift) +
((ofs & (nand->oobblock - 1)) >> 1));
} else {
NanD_Address(nand, ADDR_COLUMN_PAGE, ofs);
}
/* update address for 2M x 8bit devices. OOB starts on the second */
/* page to maintain compatibility with nand_read_ecc. */
if (nand->page256) {
if (!(ofs & 0x8))
ofs += 0x100;
else
ofs -= 0x8;
}
/* issue the Serial Data In command to initial the Page Program process */
NanD_Command(nand, NAND_CMD_SEQIN);
if (nand->bus16) {
NanD_Address(nand, ADDR_COLUMN_PAGE,
((ofs >> nand->page_shift) << nand->page_shift) +
((ofs & (nand->oobblock - 1)) >> 1));
} else {
NanD_Address(nand, ADDR_COLUMN_PAGE, ofs);
}
/* 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 (nand->page256 && ofs + len > (ofs | 0x7) + 1) {
len256 = (ofs | 0x7) + 1 - ofs;
for (i = 0; i < len256; i++)
WRITE_NAND(buf[i], nandptr);
NanD_Command(nand, NAND_CMD_PAGEPROG);
NanD_Command(nand, NAND_CMD_STATUS);
#ifdef NAND_NO_RB
{ u_char ret_val;
do {
ret_val = READ_NAND(nandptr); /* wait till ready */
} while ((ret_val & 0x40) != 0x40);
}
#endif
if (READ_NAND(nandptr) & 1) {
puts ("Error programming oob data\n");
/* There was an error */
NAND_DISABLE_CE(nand); /* set pin high */
*retlen = 0;
return -1;
}
NanD_Command(nand, NAND_CMD_SEQIN);
NanD_Address(nand, ADDR_COLUMN_PAGE, ofs & (~0x1ff));
}
if (nand->bus16) {
for (i = len256; i < len; i += 2) {
WRITE_NAND(buf[i] + (buf[i+1] << 8), nandptr);
}
} else {
for (i = len256; i < len; i++)
WRITE_NAND(buf[i], nandptr);
}
NanD_Command(nand, NAND_CMD_PAGEPROG);
NanD_Command(nand, NAND_CMD_STATUS);
#ifdef NAND_NO_RB
{ u_char ret_val;
do {
ret_val = READ_NAND(nandptr); /* wait till ready */
} while ((ret_val & 0x40) != 0x40);
}
#endif
if (READ_NAND(nandptr) & 1) {
puts ("Error programming oob data\n");
/* There was an error */
NAND_DISABLE_CE(nand); /* set pin high */
*retlen = 0;
return -1;
}
NAND_DISABLE_CE(nand); /* set pin high */
*retlen = len;
return 0;
}
int nand_legacy_erase(struct nand_chip* nand, size_t ofs, size_t len, int clean)
{
/* This is defined as a structure so it will work on any system
* using native endian jffs2 (the default).
*/
static struct jffs2_unknown_node clean_marker = {
JFFS2_MAGIC_BITMASK,
JFFS2_NODETYPE_CLEANMARKER,
8 /* 8 bytes in this node */
};
unsigned long nandptr;
struct Nand *mychip;
int ret = 0;
if (ofs & (nand->erasesize-1) || len & (nand->erasesize-1)) {
printf ("Offset and size must be sector aligned, erasesize = %d\n",
(int) nand->erasesize);
return -1;
}
nandptr = nand->IO_ADDR;
/* Select the NAND device */
#ifdef CONFIG_OMAP1510
archflashwp(0,0);
#endif
#ifdef CONFIG_SYS_NAND_WP
NAND_WP_OFF();
#endif
NAND_ENABLE_CE(nand); /* set pin low */
/* Check the WP bit */
NanD_Command(nand, NAND_CMD_STATUS);
if (!(READ_NAND(nand->IO_ADDR) & 0x80)) {
printf ("nand_write_ecc: Device is write protected!!!\n");
ret = -1;
goto out;
}
/* Check the WP bit */
NanD_Command(nand, NAND_CMD_STATUS);
if (!(READ_NAND(nand->IO_ADDR) & 0x80)) {
printf ("%s: Device is write protected!!!\n", __FUNCTION__);
ret = -1;
goto out;
}
/* FIXME: Do nand in the background. Use timers or schedule_task() */
while(len) {
/*mychip = &nand->chips[shr(ofs, nand->chipshift)];*/
mychip = &nand->chips[ofs >> nand->chipshift];
/* always check for bad block first, genuine bad blocks
* should _never_ be erased.
*/
if (ALLOW_ERASE_BAD_DEBUG || !check_block(nand, ofs)) {
/* Select the NAND device */
NAND_ENABLE_CE(nand); /* set pin low */
NanD_Command(nand, NAND_CMD_ERASE1);
NanD_Address(nand, ADDR_PAGE, ofs);
NanD_Command(nand, NAND_CMD_ERASE2);
NanD_Command(nand, NAND_CMD_STATUS);
#ifdef NAND_NO_RB
{ u_char ret_val;
do {
ret_val = READ_NAND(nandptr); /* wait till ready */
} while ((ret_val & 0x40) != 0x40);
}
#endif
if (READ_NAND(nandptr) & 1) {
printf ("%s: Error erasing at 0x%lx\n",
__FUNCTION__, (long)ofs);
/* There was an error */
ret = -1;
goto out;
}
if (clean) {
int n; /* return value not used */
int p, l;
/* clean marker position and size depend
* on the page size, since 256 byte pages
* only have 8 bytes of oob data
*/
if (nand->page256) {
p = NAND_JFFS2_OOB8_FSDAPOS;
l = NAND_JFFS2_OOB8_FSDALEN;
} else {
p = NAND_JFFS2_OOB16_FSDAPOS;
l = NAND_JFFS2_OOB16_FSDALEN;
}
ret = nand_write_oob(nand, ofs + p, l, (size_t *)&n,
(u_char *)&clean_marker);
/* quit here if write failed */
if (ret)
goto out;
}
}
ofs += nand->erasesize;
len -= nand->erasesize;
}
out:
/* De-select the NAND device */
NAND_DISABLE_CE(nand); /* set pin high */
#ifdef CONFIG_OMAP1510
archflashwp(0,1);
#endif
#ifdef CONFIG_SYS_NAND_WP
NAND_WP_ON();
#endif
return ret;
}
static inline int nandcheck(unsigned long potential, unsigned long physadr)
{
return 0;
}
unsigned long nand_probe(unsigned long physadr)
{
struct nand_chip *nand = NULL;
int i = 0, ChipID = 1;
#ifdef CONFIG_MTD_NAND_ECC_JFFS2
oob_config.ecc_pos[0] = NAND_JFFS2_OOB_ECCPOS0;
oob_config.ecc_pos[1] = NAND_JFFS2_OOB_ECCPOS1;
oob_config.ecc_pos[2] = NAND_JFFS2_OOB_ECCPOS2;
oob_config.ecc_pos[3] = NAND_JFFS2_OOB_ECCPOS3;
oob_config.ecc_pos[4] = NAND_JFFS2_OOB_ECCPOS4;
oob_config.ecc_pos[5] = NAND_JFFS2_OOB_ECCPOS5;
oob_config.eccvalid_pos = 4;
#else
oob_config.ecc_pos[0] = NAND_NOOB_ECCPOS0;
oob_config.ecc_pos[1] = NAND_NOOB_ECCPOS1;
oob_config.ecc_pos[2] = NAND_NOOB_ECCPOS2;
oob_config.ecc_pos[3] = NAND_NOOB_ECCPOS3;
oob_config.ecc_pos[4] = NAND_NOOB_ECCPOS4;
oob_config.ecc_pos[5] = NAND_NOOB_ECCPOS5;
oob_config.eccvalid_pos = NAND_NOOB_ECCVPOS;
#endif
oob_config.badblock_pos = 5;
for (i=0; i<CONFIG_SYS_MAX_NAND_DEVICE; i++) {
if (nand_dev_desc[i].ChipID == NAND_ChipID_UNKNOWN) {
nand = &nand_dev_desc[i];
break;
}
}
if (!nand)
return (0);
memset((char *)nand, 0, sizeof(struct nand_chip));
nand->IO_ADDR = physadr;
nand->cache_page = -1; /* init the cache page */
NanD_ScanChips(nand);
if (nand->totlen == 0) {
/* no chips found, clean up and quit */
memset((char *)nand, 0, sizeof(struct nand_chip));
nand->ChipID = NAND_ChipID_UNKNOWN;
return (0);
}
nand->ChipID = ChipID;
if (curr_device == -1)
curr_device = i;
nand->data_buf = malloc (nand->oobblock + nand->oobsize);
if (!nand->data_buf) {
puts ("Cannot allocate memory for data structures.\n");
return (0);
}
return (nand->totlen);
}
#ifdef CONFIG_MTD_NAND_ECC
/*
* Pre-calculated 256-way 1 byte column parity
*/
static const u_char nand_ecc_precalc_table[] = {
0x00, 0x55, 0x56, 0x03, 0x59, 0x0c, 0x0f, 0x5a,
0x5a, 0x0f, 0x0c, 0x59, 0x03, 0x56, 0x55, 0x00,
0x65, 0x30, 0x33, 0x66, 0x3c, 0x69, 0x6a, 0x3f,
0x3f, 0x6a, 0x69, 0x3c, 0x66, 0x33, 0x30, 0x65,
0x66, 0x33, 0x30, 0x65, 0x3f, 0x6a, 0x69, 0x3c,
0x3c, 0x69, 0x6a, 0x3f, 0x65, 0x30, 0x33, 0x66,
0x03, 0x56, 0x55, 0x00, 0x5a, 0x0f, 0x0c, 0x59,
0x59, 0x0c, 0x0f, 0x5a, 0x00, 0x55, 0x56, 0x03,
0x69, 0x3c, 0x3f, 0x6a, 0x30, 0x65, 0x66, 0x33,
0x33, 0x66, 0x65, 0x30, 0x6a, 0x3f, 0x3c, 0x69,
0x0c, 0x59, 0x5a, 0x0f, 0x55, 0x00, 0x03, 0x56,
0x56, 0x03, 0x00, 0x55, 0x0f, 0x5a, 0x59, 0x0c,
0x0f, 0x5a, 0x59, 0x0c, 0x56, 0x03, 0x00, 0x55,
0x55, 0x00, 0x03, 0x56, 0x0c, 0x59, 0x5a, 0x0f,
0x6a, 0x3f, 0x3c, 0x69, 0x33, 0x66, 0x65, 0x30,
0x30, 0x65, 0x66, 0x33, 0x69, 0x3c, 0x3f, 0x6a,
0x6a, 0x3f, 0x3c, 0x69, 0x33, 0x66, 0x65, 0x30,
0x30, 0x65, 0x66, 0x33, 0x69, 0x3c, 0x3f, 0x6a,
0x0f, 0x5a, 0x59, 0x0c, 0x56, 0x03, 0x00, 0x55,
0x55, 0x00, 0x03, 0x56, 0x0c, 0x59, 0x5a, 0x0f,
0x0c, 0x59, 0x5a, 0x0f, 0x55, 0x00, 0x03, 0x56,
0x56, 0x03, 0x00, 0x55, 0x0f, 0x5a, 0x59, 0x0c,
0x69, 0x3c, 0x3f, 0x6a, 0x30, 0x65, 0x66, 0x33,
0x33, 0x66, 0x65, 0x30, 0x6a, 0x3f, 0x3c, 0x69,
0x03, 0x56, 0x55, 0x00, 0x5a, 0x0f, 0x0c, 0x59,
0x59, 0x0c, 0x0f, 0x5a, 0x00, 0x55, 0x56, 0x03,
0x66, 0x33, 0x30, 0x65, 0x3f, 0x6a, 0x69, 0x3c,
0x3c, 0x69, 0x6a, 0x3f, 0x65, 0x30, 0x33, 0x66,
0x65, 0x30, 0x33, 0x66, 0x3c, 0x69, 0x6a, 0x3f,
0x3f, 0x6a, 0x69, 0x3c, 0x66, 0x33, 0x30, 0x65,
0x00, 0x55, 0x56, 0x03, 0x59, 0x0c, 0x0f, 0x5a,
0x5a, 0x0f, 0x0c, 0x59, 0x03, 0x56, 0x55, 0x00
};
/*
* Creates non-inverted ECC code from line parity
*/
static void nand_trans_result(u_char reg2, u_char reg3,
u_char *ecc_code)
{
u_char a, b, i, tmp1, tmp2;
/* Initialize variables */
a = b = 0x80;
tmp1 = tmp2 = 0;
/* Calculate first ECC byte */
for (i = 0; i < 4; i++) {
if (reg3 & a) /* LP15,13,11,9 --> ecc_code[0] */
tmp1 |= b;
b >>= 1;
if (reg2 & a) /* LP14,12,10,8 --> ecc_code[0] */
tmp1 |= b;
b >>= 1;
a >>= 1;
}
/* Calculate second ECC byte */
b = 0x80;
for (i = 0; i < 4; i++) {
if (reg3 & a) /* LP7,5,3,1 --> ecc_code[1] */
tmp2 |= b;
b >>= 1;
if (reg2 & a) /* LP6,4,2,0 --> ecc_code[1] */
tmp2 |= b;
b >>= 1;
a >>= 1;
}
/* Store two of the ECC bytes */
ecc_code[0] = tmp1;
ecc_code[1] = tmp2;
}
/*
* Calculate 3 byte ECC code for 256 byte block
*/
static void nand_calculate_ecc (const u_char *dat, u_char *ecc_code)
{
u_char idx, reg1, reg3;
int j;
/* Initialize variables */
reg1 = reg3 = 0;
ecc_code[0] = ecc_code[1] = ecc_code[2] = 0;
/* Build up column parity */
for(j = 0; j < 256; j++) {
/* Get CP0 - CP5 from table */
idx = nand_ecc_precalc_table[dat[j]];
reg1 ^= idx;
/* All bit XOR = 1 ? */
if (idx & 0x40) {
reg3 ^= (u_char) j;
}
}
/* Create non-inverted ECC code from line parity */
nand_trans_result((reg1 & 0x40) ? ~reg3 : reg3, reg3, ecc_code);
/* Calculate final ECC code */
ecc_code[0] = ~ecc_code[0];
ecc_code[1] = ~ecc_code[1];
ecc_code[2] = ((~reg1) << 2) | 0x03;
}
/*
* Detect and correct a 1 bit error for 256 byte block
*/
static int nand_correct_data (u_char *dat, u_char *read_ecc, u_char *calc_ecc)
{
u_char a, b, c, d1, d2, d3, add, bit, i;
/* Do error detection */
d1 = calc_ecc[0] ^ read_ecc[0];
d2 = calc_ecc[1] ^ read_ecc[1];
d3 = calc_ecc[2] ^ read_ecc[2];
if ((d1 | d2 | d3) == 0) {
/* No errors */
return 0;
} else {
a = (d1 ^ (d1 >> 1)) & 0x55;
b = (d2 ^ (d2 >> 1)) & 0x55;
c = (d3 ^ (d3 >> 1)) & 0x54;
/* Found and will correct single bit error in the data */
if ((a == 0x55) && (b == 0x55) && (c == 0x54)) {
c = 0x80;
add = 0;
a = 0x80;
for (i=0; i<4; i++) {
if (d1 & c)
add |= a;
c >>= 2;
a >>= 1;
}
c = 0x80;
for (i=0; i<4; i++) {
if (d2 & c)
add |= a;
c >>= 2;
a >>= 1;
}
bit = 0;
b = 0x04;
c = 0x80;
for (i=0; i<3; i++) {
if (d3 & c)
bit |= b;
c >>= 2;
b >>= 1;
}
b = 0x01;
a = dat[add];
a ^= (b << bit);
dat[add] = a;
return 1;
}
else {
i = 0;
while (d1) {
if (d1 & 0x01)
++i;
d1 >>= 1;
}
while (d2) {
if (d2 & 0x01)
++i;
d2 >>= 1;
}
while (d3) {
if (d3 & 0x01)
++i;
d3 >>= 1;
}
if (i == 1) {
/* ECC Code Error Correction */
read_ecc[0] = calc_ecc[0];
read_ecc[1] = calc_ecc[1];
read_ecc[2] = calc_ecc[2];
return 2;
}
else {
/* Uncorrectable Error */
return -1;
}
}
}
/* Should never happen */
return -1;
}
#endif
#ifdef CONFIG_JFFS2_NAND
int read_jffs2_nand(size_t start, size_t len,
size_t * retlen, u_char * buf, int nanddev)
{
return nand_legacy_rw(nand_dev_desc + nanddev, NANDRW_READ | NANDRW_JFFS2,
start, len, retlen, buf);
}
#endif /* CONFIG_JFFS2_NAND */
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