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barebox/common/cmd_nand.c

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/*
* Driver for NAND support, Rick Bronson
* borrowed heavily from:
* (c) 1999 Machine Vision Holdings, Inc.
* (c) 1999, 2000 David Woodhouse <dwmw2@infradead.org>
*
*/
#include <common.h>
#include <config.h>
#include <command.h>
#include <malloc.h>
#include <asm/io.h>
#ifdef CONFIG_SHOW_BOOT_PROGRESS
# include <status_led.h>
# define SHOW_BOOT_PROGRESS(arg) show_boot_progress(arg)
#else
# define SHOW_BOOT_PROGRESS(arg)
#endif
#if (CONFIG_COMMANDS & CFG_CMD_NAND)
#include <linux/mtd/nftl.h>
#include <linux/mtd/nand.h>
#include <linux/mtd/nand_ids.h>
/*
* Definition of the out of band configuration structure
*/
struct nand_oob_config {
int ecc_pos[6]; /* position of ECC bytes inside oob */
int badblock_pos; /* position of bad block flag inside oob -1 = inactive */
int eccvalid_pos; /* position of ECC valid flag inside oob -1 = inactive */
} oob_config = { {0}, 0, 0};
#define NAND_DEBUG
#undef ECC_DEBUG
#undef PSYCHO_DEBUG
#undef NFTL_DEBUG
#define CONFIG_MTD_NAND_ECC /* enable ECC */
/* #define CONFIG_MTD_NAND_ECC_JFFS2 */
/*
* Function Prototypes
*/
static void nand_print(struct nand_chip *nand);
static int nand_rw (struct nand_chip* nand, int cmd,
size_t start, size_t len,
size_t * retlen, u_char * buf);
static int nand_erase(struct nand_chip* nand, size_t ofs, size_t len);
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
static struct nand_chip nand_dev_desc[CFG_MAX_NAND_DEVICE] = {{0}};
/* Current NAND Device */
static int curr_device = -1;
/* ------------------------------------------------------------------------- */
int do_nand (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
{
int rcode = 0;
switch (argc) {
case 0:
case 1:
printf ("Usage:\n%s\n", cmdtp->usage);
return 1;
case 2:
if (strcmp(argv[1],"info") == 0) {
int i;
putc ('\n');
for (i=0; i<CFG_MAX_NAND_DEVICE; ++i) {
if(nand_dev_desc[i].ChipID == NAND_ChipID_UNKNOWN)
continue; /* list only known devices */
printf ("Device %d: ", i);
nand_print(&nand_dev_desc[i]);
}
return 0;
} else if (strcmp(argv[1],"device") == 0) {
if ((curr_device < 0) || (curr_device >= CFG_MAX_NAND_DEVICE)) {
puts ("\nno devices available\n");
return 1;
}
printf ("\nDevice %d: ", curr_device);
nand_print(&nand_dev_desc[curr_device]);
return 0;
}
printf ("Usage:\n%s\n", cmdtp->usage);
return 1;
case 3:
if (strcmp(argv[1],"device") == 0) {
int dev = (int)simple_strtoul(argv[2], NULL, 10);
printf ("\nDevice %d: ", dev);
if (dev >= CFG_MAX_NAND_DEVICE) {
puts ("unknown device\n");
return 1;
}
nand_print(&nand_dev_desc[dev]);
/*nand_print (dev);*/
if (nand_dev_desc[dev].ChipID == NAND_ChipID_UNKNOWN) {
return 1;
}
curr_device = dev;
puts ("... is now current device\n");
return 0;
}
printf ("Usage:\n%s\n", cmdtp->usage);
return 1;
default:
/* at least 4 args */
if (strcmp(argv[1],"read") == 0 || strcmp(argv[1],"write") == 0) {
ulong addr = simple_strtoul(argv[2], NULL, 16);
ulong off = simple_strtoul(argv[3], NULL, 16);
ulong size = simple_strtoul(argv[4], NULL, 16);
int cmd = (strcmp(argv[1],"read") == 0);
int ret, total;
printf ("\nNAND %s: device %d offset %ld, size %ld ... ",
cmd ? "read" : "write", curr_device, off, size);
ret = nand_rw(nand_dev_desc + curr_device, cmd, off, size,
&total, (u_char*)addr);
printf ("%d bytes %s: %s\n", total, cmd ? "read" : "write",
ret ? "ERROR" : "OK");
return ret;
} else if (strcmp(argv[1],"erase") == 0) {
ulong off = simple_strtoul(argv[2], NULL, 16);
ulong size = simple_strtoul(argv[3], NULL, 16);
int ret;
printf ("\nNAND erase: device %d offset %ld, size %ld ... ",
curr_device, off, size);
ret = nand_erase (nand_dev_desc + curr_device, off, size);
printf("%s\n", ret ? "ERROR" : "OK");
return ret;
} else {
printf ("Usage:\n%s\n", cmdtp->usage);
rcode = 1;
}
return rcode;
}
}
int do_nandboot (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
{
char *boot_device = NULL;
char *ep;
int dev;
ulong cnt;
ulong addr;
ulong offset = 0;
image_header_t *hdr;
int rcode = 0;
switch (argc) {
case 1:
addr = CFG_LOAD_ADDR;
boot_device = getenv ("bootdevice");
break;
case 2:
addr = simple_strtoul(argv[1], NULL, 16);
boot_device = getenv ("bootdevice");
break;
case 3:
addr = simple_strtoul(argv[1], NULL, 16);
boot_device = argv[2];
break;
case 4:
addr = simple_strtoul(argv[1], NULL, 16);
boot_device = argv[2];
offset = simple_strtoul(argv[3], NULL, 16);
break;
default:
printf ("Usage:\n%s\n", cmdtp->usage);
SHOW_BOOT_PROGRESS (-1);
return 1;
}
if (!boot_device) {
puts ("\n** No boot device **\n");
SHOW_BOOT_PROGRESS (-1);
return 1;
}
dev = simple_strtoul(boot_device, &ep, 16);
if ((dev >= CFG_MAX_NAND_DEVICE) ||
(nand_dev_desc[dev].ChipID == NAND_ChipID_UNKNOWN)) {
printf ("\n** Device %d not available\n", dev);
SHOW_BOOT_PROGRESS (-1);
return 1;
}
printf ("\nLoading from device %d: %s at 0x%lX (offset 0x%lX)\n",
dev, nand_dev_desc[dev].name, nand_dev_desc[dev].IO_ADDR,
offset);
if (nand_rw (nand_dev_desc + dev, 1, offset,
SECTORSIZE, NULL, (u_char *)addr)) {
printf ("** Read error on %d\n", dev);
SHOW_BOOT_PROGRESS (-1);
return 1;
}
hdr = (image_header_t *)addr;
if (ntohl(hdr->ih_magic) == IH_MAGIC) {
print_image_hdr (hdr);
cnt = (ntohl(hdr->ih_size) + sizeof(image_header_t));
cnt -= SECTORSIZE;
} else {
printf ("\n** Bad Magic Number 0x%x **\n", hdr->ih_magic);
SHOW_BOOT_PROGRESS (-1);
return 1;
}
if (nand_rw (nand_dev_desc + dev, 1, offset + SECTORSIZE, cnt,
NULL, (u_char *)(addr+SECTORSIZE))) {
printf ("** Read error on %d\n", dev);
SHOW_BOOT_PROGRESS (-1);
return 1;
}
/* Loading ok, update default load address */
load_addr = addr;
/* Check if we should attempt an auto-start */
if (((ep = getenv("autostart")) != NULL) && (strcmp(ep,"yes") == 0)) {
char *local_args[2];
extern int do_bootm (cmd_tbl_t *, int, int, char *[]);
local_args[0] = argv[0];
local_args[1] = NULL;
printf ("Automatic boot of image at addr 0x%08lX ...\n", addr);
do_bootm (cmdtp, 0, 1, local_args);
rcode = 1;
}
return rcode;
}
static int nand_rw (struct nand_chip* nand, int cmd,
size_t start, size_t len,
size_t * retlen, u_char * buf)
{
int noecc, ret = 0, n, total = 0;
char eccbuf[6];
while(len) {
/* The ECC will not be calculated correctly if
less than 512 is written or read */
noecc = (start != (start | 0x1ff) + 1) || (len < 0x200);
if (cmd)
ret = nand_read_ecc(nand, start, len,
&n, (u_char*)buf,
noecc ? NULL : eccbuf);
else
ret = nand_write_ecc(nand, start, len,
&n, (u_char*)buf,
noecc ? NULL : eccbuf);
if (ret)
break;
start += n;
buf += n;
total += n;
len -= n;
}
if (retlen)
*retlen = total;
return ret;
}
static void nand_print(struct nand_chip *nand)
{
printf("%s at 0x%lX,\n"
"\t %d chip%s %s, size %d MB, \n"
"\t total size %ld MB, sector size %ld kB\n",
nand->name, nand->IO_ADDR, nand->numchips,
nand->numchips>1 ? "s" : "", nand->chips_name,
1 << (nand->chipshift - 20),
nand->totlen >> 20, nand->erasesize >> 10);
if (nand->nftl_found) {
struct NFTLrecord *nftl = &nand->nftl;
unsigned long bin_size, flash_size;
bin_size = nftl->nb_boot_blocks * nand->erasesize;
flash_size = (nftl->nb_blocks - nftl->nb_boot_blocks) * nand->erasesize;
printf("\t NFTL boot record:\n"
"\t Binary partition: size %ld%s\n"
"\t Flash disk partition: size %ld%s, offset 0x%lx\n",
bin_size > (1 << 20) ? bin_size >> 20 : bin_size >> 10,
bin_size > (1 << 20) ? "MB" : "kB",
flash_size > (1 << 20) ? flash_size >> 20 : flash_size >> 10,
flash_size > (1 << 20) ? "MB" : "kB", bin_size);
} else {
puts ("\t No NFTL boot record found.\n");
}
}
/* ------------------------------------------------------------------------- */
/* This function is needed to avoid calls of the __ashrdi3 function. */
static int shr(int val, int shift)
{
return val >> shift;
}
static int NanD_WaitReady(struct nand_chip *nand)
{
/* This is inline, to optimise the common case, where it's ready instantly */
int ret = 0;
NAND_WAIT_READY(nand);
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);
return NanD_WaitReady(nand);
}
/* 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);
}
/* 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);
}
/* 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 */
/* No response - return failure */
if (mfr == 0xff || mfr == 0)
{
printf("NanD_Command (ReadID) got %d %d\n", mfr, id);
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;
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;
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 = 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) {
puts ("No flash chips recognised.\n");
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
}
#ifdef CONFIG_MTD_NAND_ECC
/* we need to be fast here, 1 us per read translates to 1 second per meg */
static void nand_fast_copy (unsigned char *source, unsigned char *dest, long cntr)
{
while (cntr > 16)
{
*dest++ = *source++;
*dest++ = *source++;
*dest++ = *source++;
*dest++ = *source++;
*dest++ = *source++;
*dest++ = *source++;
*dest++ = *source++;
*dest++ = *source++;
*dest++ = *source++;
*dest++ = *source++;
*dest++ = *source++;
*dest++ = *source++;
*dest++ = *source++;
*dest++ = *source++;
*dest++ = *source++;
*dest++ = *source++;
cntr -= 16;
}
while (cntr > 0)
{
*dest++ = *source++;
cntr--;
}
}
#endif
/* we need to be fast here, 1 us per read translates to 1 second per meg */
static void nand_fast_read(unsigned char *data_buf, int cntr, unsigned long nandptr)
{
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--;
}
}
/* 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.
*/
/*
* 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
unsigned long nandptr = nand->IO_ADDR;
/* Do not allow reads past end of device */
if ((start + len) > nand->totlen) {
printf ("nand_read_ecc: Attempt read beyond end of device %x %x %x\n", (uint) start, (uint) len, (uint) nand->totlen);
*retlen = 0;
return -1;
}
/* First we calculate the starting page */
page = shr(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);
NanD_Address(nand, ADDR_COLUMN_PAGE, (page << nand->page_shift) + col);
/* Read in a page + oob data */
nand_fast_read(nand->data_buf, nand->oobblock + nand->oobsize, nandptr);
/* 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 ("nand_read_ecc: " "Failed ECC read, page 0x%08x\n", page);
ecc_failed++;
break;
case 1:
case 2: /* transfer ECC corrected data to 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 ("nand_read_ecc: " "Failed ECC read, page 0x%08x\n", 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) {
nand_fast_copy (data_poi, buf + *retlen, len - *retlen);
*retlen = len;
} else {
nand_fast_copy (data_poi, buf + *retlen, 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);
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_fast_read(buf + *retlen, len - *retlen, nandptr);
*retlen = len;
/* We're done */
continue;
} else {
nand_fast_read(buf + *retlen, nand->oobblock - col, nandptr);
*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;
#ifdef CONFIG_MTD_NAND_ECC
unsigned long nandptr = nand->IO_ADDR;
#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);
NanD_Address(nand, ADDR_COLUMN_PAGE, (page << nand->page_shift) + col);
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_SEQIN);
NanD_Address(nand, ADDR_COLUMN_PAGE, (page << nand->page_shift) + col);
/* Write out complete page of data */
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);
/* See if device thinks it succeeded */
if (READ_NAND(nand->IO_ADDR) & 0x01) {
printf ("nand_write_ecc: " "Failed write, page 0x%08x, ", 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);
NanD_Address(nand, ADDR_COLUMN_PAGE, (page << nand->page_shift) + col);
/* Loop through and verify the data */
for (i = col; i < last; i++) {
if (nand->data_buf[i] != readb (nand->IO_ADDR)) {
printf ("nand_write_ecc: " "Failed write verify, page 0x%08x ", 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);
NanD_Address(nand, ADDR_COLUMN_PAGE, (page << nand->page_shift) + col);
for (i = 0; i < nand->oobsize; i++)
nand->data_buf[i] = readb (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 ("nand_write_ecc: Failed ECC write "
"verify, page 0x%08x, " "%6i bytes were succesful\n", page, i);
return -1;
}
}
#endif
#endif
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 ("nand_write_oob: Attempt to write past end of page\n");
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 */
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;
}
/* 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 */
return ret;
}
#if 0 /* not used */
/* Read a buffer from NanD */
static void NanD_ReadBuf(struct nand_chip *nand, u_char * buf, int len)
{
unsigned long nandptr;
nandptr = nand->IO_ADDR;
for (; len > 0; len--)
*buf++ = READ_NAND(nandptr);
}
/* Write a buffer to NanD */
static void NanD_WriteBuf(struct nand_chip *nand, const u_char * buf, int len)
{
unsigned long nandptr;
int i;
nandptr = nand->IO_ADDR;
if (len <= 0)
return;
for (i = 0; i < len; i++)
WRITE_NAND(buf[i], nandptr);
}
/* find_boot_record: Find the NFTL Media Header and its Spare copy which contains the
* various device information of the NFTL partition and Bad Unit Table. Update
* the ReplUnitTable[] table accroding to the Bad Unit Table. ReplUnitTable[]
* is used for management of Erase Unit in other routines in nftl.c and nftlmount.c
*/
static int find_boot_record(struct NFTLrecord *nftl)
{
struct nftl_uci1 h1;
struct nftl_oob oob;
unsigned int block, boot_record_count = 0;
int retlen;
u8 buf[SECTORSIZE];
struct NFTLMediaHeader *mh = &nftl->MediaHdr;
unsigned int i;
nftl->MediaUnit = BLOCK_NIL;
nftl->SpareMediaUnit = BLOCK_NIL;
/* search for a valid boot record */
for (block = 0; block < nftl->nb_blocks; block++) {
int ret;
/* Check for ANAND header first. Then can whinge if it's found but later
checks fail */
if ((ret = nand_read_ecc(nftl->mtd, block * nftl->EraseSize, SECTORSIZE,
&retlen, buf, NULL))) {
static int warncount = 5;
if (warncount) {
printf("Block read at 0x%x failed\n", block * nftl->EraseSize);
if (!--warncount)
puts ("Further failures for this block will not be printed\n");
}
continue;
}
if (retlen < 6 || memcmp(buf, "ANAND", 6)) {
/* ANAND\0 not found. Continue */
#ifdef PSYCHO_DEBUG
printf("ANAND header not found at 0x%x\n", block * nftl->EraseSize);
#endif
continue;
}
#ifdef NFTL_DEBUG
printf("ANAND header found at 0x%x\n", block * nftl->EraseSize);
#endif
/* To be safer with BIOS, also use erase mark as discriminant */
if ((ret = nand_read_oob(nftl->mtd, block * nftl->EraseSize + SECTORSIZE + 8,
8, &retlen, (char *)&h1) < 0)) {
#ifdef NFTL_DEBUG
printf("ANAND header found at 0x%x, but OOB data read failed\n",
block * nftl->EraseSize);
#endif
continue;
}
/* OK, we like it. */
if (boot_record_count) {
/* We've already processed one. So we just check if
this one is the same as the first one we found */
if (memcmp(mh, buf, sizeof(struct NFTLMediaHeader))) {
#ifdef NFTL_DEBUG
printf("NFTL Media Headers at 0x%x and 0x%x disagree.\n",
nftl->MediaUnit * nftl->EraseSize, block * nftl->EraseSize);
#endif
/* if (debug) Print both side by side */
return -1;
}
if (boot_record_count == 1)
nftl->SpareMediaUnit = block;
boot_record_count++;
continue;
}
/* This is the first we've seen. Copy the media header structure into place */
memcpy(mh, buf, sizeof(struct NFTLMediaHeader));
/* Do some sanity checks on it */
if (mh->UnitSizeFactor != 0xff) {
puts ("Sorry, we don't support UnitSizeFactor "
"of != 1 yet.\n");
return -1;
}
nftl->nb_boot_blocks = le16_to_cpu(mh->FirstPhysicalEUN);
if ((nftl->nb_boot_blocks + 2) >= nftl->nb_blocks) {
printf ("NFTL Media Header sanity check failed:\n"
"nb_boot_blocks (%d) + 2 > nb_blocks (%d)\n",
nftl->nb_boot_blocks, nftl->nb_blocks);
return -1;
}
nftl->numvunits = le32_to_cpu(mh->FormattedSize) / nftl->EraseSize;
if (nftl->numvunits > (nftl->nb_blocks - nftl->nb_boot_blocks - 2)) {
printf ("NFTL Media Header sanity check failed:\n"
"numvunits (%d) > nb_blocks (%d) - nb_boot_blocks(%d) - 2\n",
nftl->numvunits,
nftl->nb_blocks,
nftl->nb_boot_blocks);
return -1;
}
nftl->nr_sects = nftl->numvunits * (nftl->EraseSize / SECTORSIZE);
/* If we're not using the last sectors in the device for some reason,
reduce nb_blocks accordingly so we forget they're there */
nftl->nb_blocks = le16_to_cpu(mh->NumEraseUnits) + le16_to_cpu(mh->FirstPhysicalEUN);
/* read the Bad Erase Unit Table and modify ReplUnitTable[] accordingly */
for (i = 0; i < nftl->nb_blocks; i++) {
if ((i & (SECTORSIZE - 1)) == 0) {
/* read one sector for every SECTORSIZE of blocks */
if ((ret = nand_read_ecc(nftl->mtd, block * nftl->EraseSize +
i + SECTORSIZE, SECTORSIZE,
&retlen, buf, (char *)&oob)) < 0) {
puts ("Read of bad sector table failed\n");
return -1;
}
}
/* mark the Bad Erase Unit as RESERVED in ReplUnitTable */
if (buf[i & (SECTORSIZE - 1)] != 0xff)
nftl->ReplUnitTable[i] = BLOCK_RESERVED;
}
nftl->MediaUnit = block;
boot_record_count++;
} /* foreach (block) */
return boot_record_count?0:-1;
}
static int nand_read_oob(struct nand_chip* nand, size_t ofs, size_t len,
size_t * retlen, u_char * buf)
{
int len256 = 0, ret;
unsigned long nandptr;
struct Nand *mychip;
nandptr = nand->IO_ADDR;
mychip = &nand->chips[shr(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_Command(nand, NAND_CMD_READOOB);
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);
return ret;
}
static int nand_write_oob(struct nand_chip* nand, size_t ofs, size_t len,
size_t * retlen, const u_char * buf)
{
int len256 = 0;
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
/* 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);
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);
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_WriteBuf(nand, buf, len256);
NanD_Command(nand, NAND_CMD_PAGEPROG);
NanD_Command(nand, NAND_CMD_STATUS);
/* NanD_WaitReady() is implicit in NanD_Command */
if (READ_NAND(nandptr) & 1) {
puts ("Error programming oob data\n");
/* There was an error */
*retlen = 0;
return -1;
}
NanD_Command(nand, NAND_CMD_SEQIN);
NanD_Address(nand, ADDR_COLUMN_PAGE, ofs & (~0x1ff));
}
NanD_WriteBuf(nand, &buf[len256], len - len256);
NanD_Command(nand, NAND_CMD_PAGEPROG);
NanD_Command(nand, NAND_CMD_STATUS);
/* NanD_WaitReady() is implicit in NanD_Command */
if (READ_NAND(nandptr) & 1) {
puts ("Error programming oob data\n");
/* There was an error */
*retlen = 0;
return -1;
}
*retlen = len;
return 0;
}
#endif
static int nand_erase(struct nand_chip* nand, size_t ofs, size_t len)
{
unsigned long nandptr;
struct Nand *mychip;
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;
/* FIXME: Do nand in the background. Use timers or schedule_task() */
while(len) {
mychip = &nand->chips[shr(ofs, nand->chipshift)];
NanD_Command(nand, NAND_CMD_ERASE1);
NanD_Address(nand, ADDR_PAGE, ofs);
NanD_Command(nand, NAND_CMD_ERASE2);
NanD_Command(nand, NAND_CMD_STATUS);
if (READ_NAND(nandptr) & 1) {
printf("Error erasing at 0x%lx\n", (long)ofs);
/* There was an error */
goto callback;
}
ofs += nand->erasesize;
len -= nand->erasesize;
}
callback:
return 0;
}
static inline int nandcheck(unsigned long potential, unsigned long physadr)
{
return 0;
}
void 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.badblock_pos = 5;
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.badblock_pos = NAND_NOOB_BADBPOS;
oob_config.eccvalid_pos = NAND_NOOB_ECCVPOS;
#endif
for (i=0; i<CFG_MAX_NAND_DEVICE; i++) {
if (nand_dev_desc[i].ChipID == NAND_ChipID_UNKNOWN) {
nand = nand_dev_desc + i;
break;
}
}
if (curr_device == -1)
curr_device = i;
memset((char *)nand, 0, sizeof(struct nand_chip));
nand->cache_page = -1; /* init the cache page */
nand->IO_ADDR = physadr;
nand->ChipID = ChipID;
NanD_ScanChips(nand);
nand->data_buf = malloc (nand->oobblock + nand->oobsize);
if (!nand->data_buf) {
puts ("Cannot allocate memory for data structures.\n");
return;
}
}
#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, reg2, reg3;
int j;
/* Initialize variables */
reg1 = reg2 = 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 & 0x3f);
/* All bit XOR = 1 ? */
if (idx & 0x40) {
reg3 ^= (u_char) j;
reg2 ^= ~((u_char) j);
}
}
/* Create non-inverted ECC code from line parity */
nand_trans_result(reg2, 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
#endif /* (CONFIG_COMMANDS & CFG_CMD_NAND) */
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