diff options
Diffstat (limited to 'drivers/mtd/nand_legacy/nand_legacy.c')
| -rw-r--r-- | drivers/mtd/nand_legacy/nand_legacy.c | 1612 |
1 files changed, 1612 insertions, 0 deletions
diff --git a/drivers/mtd/nand_legacy/nand_legacy.c b/drivers/mtd/nand_legacy/nand_legacy.c new file mode 100644 index 0000000..49d2ebb --- /dev/null +++ b/drivers/mtd/nand_legacy/nand_legacy.c @@ -0,0 +1,1612 @@ +/* + * (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> + +#if defined(CONFIG_CMD_NAND) && defined(CFG_NAND_LEGACY) + +#include <linux/mtd/nand_legacy.h> +#include <linux/mtd/nand_ids.h> +#include <jffs2/jffs2.h> + +#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[CFG_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 = 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 CFG_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 CFG_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 CFG_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 CFG_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<CFG_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 */ + +#endif |