/* * Driver for NAND support, Rick Bronson * borrowed heavily from: * (c) 1999 Machine Vision Holdings, Inc. * (c) 1999, 2000 David Woodhouse */ #include #include #include #include #ifdef CONFIG_SHOW_BOOT_PROGRESS # include # define SHOW_BOOT_PROGRESS(arg) show_boot_progress(arg) #else # define SHOW_BOOT_PROGRESS(arg) #endif #if (CONFIG_COMMANDS & CFG_CMD_NAND) #include #include #include #ifdef CONFIG_OMAP1510 void archflashwp(void *archdata, int wp); #endif #define ROUND_DOWN(value,boundary) ((value) & (~((boundary)-1))) /* * 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}; #undef NAND_DEBUG #undef PSYCHO_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_rw() `cmd'; or together as needed */ #define NANDRW_READ 0x01 #define NANDRW_WRITE 0x00 #define NANDRW_JFFS2 0x02 /* * 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, int clean); 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); static void nand_print_bad(struct nand_chip *nand); static int nand_read_oob(struct nand_chip* nand, size_t ofs, size_t len, size_t * retlen, u_char * buf); static int nand_write_oob(struct nand_chip* nand, size_t ofs, size_t len, size_t * retlen, const u_char * buf); static int NanD_WaitReady(struct nand_chip *nand, int ale_wait); #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 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)) { puts ("\nno devices available\n"); return 1; } printf ("\nDevice %d: ", curr_device); nand_print(&nand_dev_desc[curr_device]); return 0; } else if (strcmp(argv[1],"bad") == 0) { if ((curr_device < 0) || (curr_device >= CFG_MAX_NAND_DEVICE)) { puts ("\nno devices available\n"); return 1; } printf ("\nDevice %d bad blocks:\n", curr_device); nand_print_bad(&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; } else if (strcmp(argv[1],"erase") == 0 && strcmp(argv[2], "clean") == 0) { struct nand_chip* nand = &nand_dev_desc[curr_device]; ulong off = 0; ulong size = nand->totlen; int ret; printf ("\nNAND erase: device %d offset %ld, size %ld ... ", curr_device, off, size); ret = nand_erase (nand, off, size, 1); printf("%s\n", ret ? "ERROR" : "OK"); return ret; } printf ("Usage:\n%s\n", cmdtp->usage); return 1; default: /* at least 4 args */ if (strncmp(argv[1], "read", 4) == 0 || strncmp(argv[1], "write", 5) == 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 = (strncmp(argv[1], "read", 4) == 0) ? NANDRW_READ : NANDRW_WRITE; int ret, total; char* cmdtail = strchr(argv[1], '.'); if (cmdtail && !strncmp(cmdtail, ".oob", 2)) { /* read out-of-band data */ if (cmd & NANDRW_READ) { ret = nand_read_oob(nand_dev_desc + curr_device, off, size, &total, (u_char*)addr); } else { ret = nand_write_oob(nand_dev_desc + curr_device, off, size, &total, (u_char*)addr); } return ret; } else if (cmdtail && !strncmp(cmdtail, ".jffs2", 2)) cmd |= NANDRW_JFFS2; /* skip bad blocks */ #ifdef SXNI855T /* need ".e" same as ".j" for compatibility with older units */ else if (cmdtail && !strcmp(cmdtail, ".e")) cmd |= NANDRW_JFFS2; /* skip bad blocks */ #endif else if (cmdtail) { printf ("Usage:\n%s\n", cmdtp->usage); return 1; } printf ("\nNAND %s: device %d offset %ld, size %ld ... ", (cmd & NANDRW_READ) ? "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 & NANDRW_READ) ? "read" : "write", ret ? "ERROR" : "OK"); return ret; } else if (strcmp(argv[1],"erase") == 0 && (argc == 4 || strcmp("clean", argv[2]) == 0)) { int clean = argc == 5; ulong off = simple_strtoul(argv[2 + clean], NULL, 16); ulong size = simple_strtoul(argv[3 + clean], 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, clean); printf("%s\n", ret ? "ERROR" : "OK"); return ret; } else { printf ("Usage:\n%s\n", cmdtp->usage); rcode = 1; } return rcode; } } U_BOOT_CMD( nand, 5, 1, do_nand, "nand - NAND sub-system\n", "info - show available NAND devices\n" "nand device [dev] - show or set current device\n" "nand read[.jffs2] addr off size\n" "nand write[.jffs2] addr off size - read/write `size' bytes starting\n" " at offset `off' to/from memory address `addr'\n" "nand erase [clean] [off size] - erase `size' bytes from\n" " offset `off' (entire device if not specified)\n" "nand bad - show bad blocks\n" "nand read.oob addr off size - read out-of-band data\n" "nand write.oob addr off size - read out-of-band data\n" ); 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, NANDRW_READ, 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, NANDRW_READ, 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; } U_BOOT_CMD( nboot, 4, 1, do_nandboot, "nboot - boot from NAND device\n", "loadAddr dev\n" ); /* 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 */ int check_block(struct nand_chip* nand, unsigned long pos) { int retlen; uint8_t oob_data; 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 */ /* Note - bad block marker can be on first or second page */ if (nand_read_oob(nand, page0 + badpos, 1, &retlen, &oob_data) || oob_data != 0xff || nand_read_oob(nand, page1 + badpos, 1, &retlen, &oob_data) || oob_data != 0xff) return 1; return 0; } /* print bad blocks in NAND flash */ static 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 */ static int nand_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_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), &n, (u_char*)buf, eccbuf); else ret = nand_write_ecc(nand, start, min(len, eblk + erasesize - start), &n, (u_char*)buf, 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) { 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 */ /* 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; 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; 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 } /* 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; 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); 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); 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); 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_READ0); 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); #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); 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 ("%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); 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 ("%s: Failed ECC write " "verify, page 0x%08x, " "%6i bytes were succesful\n", __FUNCTION__, 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 ("%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 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 return ret; } /* read from the 16 bytes of oob data that correspond to a 512 byte * page or 2 256-byte pages. */ static 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); 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. */ 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; 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); 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; 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)); } 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; } static int nand_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 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, &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 return ret; } 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.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; iIO_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; } 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; } } #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 #endif /* (CONFIG_COMMANDS & CFG_CMD_NAND) */