| 1 | /* |
| 2 | * drivers/mtd/nand_bbt.c |
| 3 | * |
| 4 | * Overview: |
| 5 | * Bad block table support for the NAND driver |
| 6 | * |
| 7 | * Copyright (C) 2004 Thomas Gleixner (tglx@linutronix.de) |
| 8 | * |
| 9 | * This program is free software; you can redistribute it and/or modify |
| 10 | * it under the terms of the GNU General Public License version 2 as |
| 11 | * published by the Free Software Foundation. |
| 12 | * |
| 13 | * Description: |
| 14 | * |
| 15 | * When nand_scan_bbt is called, then it tries to find the bad block table |
| 16 | * depending on the options in the BBT descriptor(s). If no flash based BBT |
| 17 | * (NAND_BBT_USE_FLASH) is specified then the device is scanned for factory |
| 18 | * marked good / bad blocks. This information is used to create a memory BBT. |
| 19 | * Once a new bad block is discovered then the "factory" information is updated |
| 20 | * on the device. |
| 21 | * If a flash based BBT is specified then the function first tries to find the |
| 22 | * BBT on flash. If a BBT is found then the contents are read and the memory |
| 23 | * based BBT is created. If a mirrored BBT is selected then the mirror is |
| 24 | * searched too and the versions are compared. If the mirror has a greater |
| 25 | * version number, then the mirror BBT is used to build the memory based BBT. |
| 26 | * If the tables are not versioned, then we "or" the bad block information. |
| 27 | * If one of the BBTs is out of date or does not exist it is (re)created. |
| 28 | * If no BBT exists at all then the device is scanned for factory marked |
| 29 | * good / bad blocks and the bad block tables are created. |
| 30 | * |
| 31 | * For manufacturer created BBTs like the one found on M-SYS DOC devices |
| 32 | * the BBT is searched and read but never created |
| 33 | * |
| 34 | * The auto generated bad block table is located in the last good blocks |
| 35 | * of the device. The table is mirrored, so it can be updated eventually. |
| 36 | * The table is marked in the OOB area with an ident pattern and a version |
| 37 | * number which indicates which of both tables is more up to date. If the NAND |
| 38 | * controller needs the complete OOB area for the ECC information then the |
| 39 | * option NAND_BBT_NO_OOB should be used (along with NAND_BBT_USE_FLASH, of |
| 40 | * course): it moves the ident pattern and the version byte into the data area |
| 41 | * and the OOB area will remain untouched. |
| 42 | * |
| 43 | * The table uses 2 bits per block |
| 44 | * 11b: block is good |
| 45 | * 00b: block is factory marked bad |
| 46 | * 01b, 10b: block is marked bad due to wear |
| 47 | * |
| 48 | * The memory bad block table uses the following scheme: |
| 49 | * 00b: block is good |
| 50 | * 01b: block is marked bad due to wear |
| 51 | * 10b: block is reserved (to protect the bbt area) |
| 52 | * 11b: block is factory marked bad |
| 53 | * |
| 54 | * Multichip devices like DOC store the bad block info per floor. |
| 55 | * |
| 56 | * Following assumptions are made: |
| 57 | * - bbts start at a page boundary, if autolocated on a block boundary |
| 58 | * - the space necessary for a bbt in FLASH does not exceed a block boundary |
| 59 | * |
| 60 | */ |
| 61 | |
| 62 | #include <linux/slab.h> |
| 63 | #include <linux/types.h> |
| 64 | #include <linux/mtd/mtd.h> |
| 65 | #include <linux/mtd/nand.h> |
| 66 | #include <linux/mtd/nand_ecc.h> |
| 67 | #include <linux/bitops.h> |
| 68 | #include <linux/delay.h> |
| 69 | #include <linux/vmalloc.h> |
| 70 | #include <linux/export.h> |
| 71 | #include <linux/string.h> |
| 72 | |
| 73 | static int check_pattern_no_oob(uint8_t *buf, struct nand_bbt_descr *td) |
| 74 | { |
| 75 | if (memcmp(buf, td->pattern, td->len)) |
| 76 | return -1; |
| 77 | return 0; |
| 78 | } |
| 79 | |
| 80 | /** |
| 81 | * check_pattern - [GENERIC] check if a pattern is in the buffer |
| 82 | * @buf: the buffer to search |
| 83 | * @len: the length of buffer to search |
| 84 | * @paglen: the pagelength |
| 85 | * @td: search pattern descriptor |
| 86 | * |
| 87 | * Check for a pattern at the given place. Used to search bad block tables and |
| 88 | * good / bad block identifiers. If the SCAN_EMPTY option is set then check, if |
| 89 | * all bytes except the pattern area contain 0xff. |
| 90 | */ |
| 91 | static int check_pattern(uint8_t *buf, int len, int paglen, struct nand_bbt_descr *td) |
| 92 | { |
| 93 | int end = 0; |
| 94 | uint8_t *p = buf; |
| 95 | |
| 96 | if (td->options & NAND_BBT_NO_OOB) |
| 97 | return check_pattern_no_oob(buf, td); |
| 98 | |
| 99 | end = paglen + td->offs; |
| 100 | if (td->options & NAND_BBT_SCANEMPTY) |
| 101 | if (memchr_inv(p, 0xff, end)) |
| 102 | return -1; |
| 103 | p += end; |
| 104 | |
| 105 | /* Compare the pattern */ |
| 106 | if (memcmp(p, td->pattern, td->len)) |
| 107 | return -1; |
| 108 | |
| 109 | if (td->options & NAND_BBT_SCANEMPTY) { |
| 110 | p += td->len; |
| 111 | end += td->len; |
| 112 | if (memchr_inv(p, 0xff, len - end)) |
| 113 | return -1; |
| 114 | } |
| 115 | return 0; |
| 116 | } |
| 117 | |
| 118 | /** |
| 119 | * check_short_pattern - [GENERIC] check if a pattern is in the buffer |
| 120 | * @buf: the buffer to search |
| 121 | * @td: search pattern descriptor |
| 122 | * |
| 123 | * Check for a pattern at the given place. Used to search bad block tables and |
| 124 | * good / bad block identifiers. Same as check_pattern, but no optional empty |
| 125 | * check. |
| 126 | */ |
| 127 | static int check_short_pattern(uint8_t *buf, struct nand_bbt_descr *td) |
| 128 | { |
| 129 | /* Compare the pattern */ |
| 130 | if (memcmp(buf + td->offs, td->pattern, td->len)) |
| 131 | return -1; |
| 132 | return 0; |
| 133 | } |
| 134 | |
| 135 | /** |
| 136 | * add_marker_len - compute the length of the marker in data area |
| 137 | * @td: BBT descriptor used for computation |
| 138 | * |
| 139 | * The length will be 0 if the marker is located in OOB area. |
| 140 | */ |
| 141 | static u32 add_marker_len(struct nand_bbt_descr *td) |
| 142 | { |
| 143 | u32 len; |
| 144 | |
| 145 | if (!(td->options & NAND_BBT_NO_OOB)) |
| 146 | return 0; |
| 147 | |
| 148 | len = td->len; |
| 149 | if (td->options & NAND_BBT_VERSION) |
| 150 | len++; |
| 151 | return len; |
| 152 | } |
| 153 | |
| 154 | /** |
| 155 | * read_bbt - [GENERIC] Read the bad block table starting from page |
| 156 | * @mtd: MTD device structure |
| 157 | * @buf: temporary buffer |
| 158 | * @page: the starting page |
| 159 | * @num: the number of bbt descriptors to read |
| 160 | * @td: the bbt describtion table |
| 161 | * @offs: offset in the memory table |
| 162 | * |
| 163 | * Read the bad block table starting from page. |
| 164 | */ |
| 165 | static int read_bbt(struct mtd_info *mtd, uint8_t *buf, int page, int num, |
| 166 | struct nand_bbt_descr *td, int offs) |
| 167 | { |
| 168 | int res, ret = 0, i, j, act = 0; |
| 169 | struct nand_chip *this = mtd->priv; |
| 170 | size_t retlen, len, totlen; |
| 171 | loff_t from; |
| 172 | int bits = td->options & NAND_BBT_NRBITS_MSK; |
| 173 | uint8_t msk = (uint8_t)((1 << bits) - 1); |
| 174 | u32 marker_len; |
| 175 | int reserved_block_code = td->reserved_block_code; |
| 176 | |
| 177 | totlen = (num * bits) >> 3; |
| 178 | marker_len = add_marker_len(td); |
| 179 | from = ((loff_t)page) << this->page_shift; |
| 180 | |
| 181 | while (totlen) { |
| 182 | len = min(totlen, (size_t)(1 << this->bbt_erase_shift)); |
| 183 | if (marker_len) { |
| 184 | /* |
| 185 | * In case the BBT marker is not in the OOB area it |
| 186 | * will be just in the first page. |
| 187 | */ |
| 188 | len -= marker_len; |
| 189 | from += marker_len; |
| 190 | marker_len = 0; |
| 191 | } |
| 192 | res = mtd_read(mtd, from, len, &retlen, buf); |
| 193 | if (res < 0) { |
| 194 | if (mtd_is_eccerr(res)) { |
| 195 | pr_info("nand_bbt: ECC error in BBT at " |
| 196 | "0x%012llx\n", from & ~mtd->writesize); |
| 197 | return res; |
| 198 | } else if (mtd_is_bitflip(res)) { |
| 199 | pr_info("nand_bbt: corrected error in BBT at " |
| 200 | "0x%012llx\n", from & ~mtd->writesize); |
| 201 | ret = res; |
| 202 | } else { |
| 203 | pr_info("nand_bbt: error reading BBT\n"); |
| 204 | return res; |
| 205 | } |
| 206 | } |
| 207 | |
| 208 | /* Analyse data */ |
| 209 | for (i = 0; i < len; i++) { |
| 210 | uint8_t dat = buf[i]; |
| 211 | for (j = 0; j < 8; j += bits, act += 2) { |
| 212 | uint8_t tmp = (dat >> j) & msk; |
| 213 | if (tmp == msk) |
| 214 | continue; |
| 215 | if (reserved_block_code && (tmp == reserved_block_code)) { |
| 216 | pr_info("nand_read_bbt: reserved block at 0x%012llx\n", |
| 217 | (loff_t)((offs << 2) + (act >> 1)) << this->bbt_erase_shift); |
| 218 | this->bbt[offs + (act >> 3)] |= 0x2 << (act & 0x06); |
| 219 | mtd->ecc_stats.bbtblocks++; |
| 220 | continue; |
| 221 | } |
| 222 | /* |
| 223 | * Leave it for now, if it's matured we can |
| 224 | * move this message to pr_debug. |
| 225 | */ |
| 226 | pr_info("nand_read_bbt: bad block at 0x%012llx\n", |
| 227 | (loff_t)((offs << 2) + (act >> 1)) << this->bbt_erase_shift); |
| 228 | /* Factory marked bad or worn out? */ |
| 229 | if (tmp == 0) |
| 230 | this->bbt[offs + (act >> 3)] |= 0x3 << (act & 0x06); |
| 231 | else |
| 232 | this->bbt[offs + (act >> 3)] |= 0x1 << (act & 0x06); |
| 233 | mtd->ecc_stats.badblocks++; |
| 234 | } |
| 235 | } |
| 236 | totlen -= len; |
| 237 | from += len; |
| 238 | } |
| 239 | return ret; |
| 240 | } |
| 241 | |
| 242 | /** |
| 243 | * read_abs_bbt - [GENERIC] Read the bad block table starting at a given page |
| 244 | * @mtd: MTD device structure |
| 245 | * @buf: temporary buffer |
| 246 | * @td: descriptor for the bad block table |
| 247 | * @chip: read the table for a specific chip, -1 read all chips; applies only if |
| 248 | * NAND_BBT_PERCHIP option is set |
| 249 | * |
| 250 | * Read the bad block table for all chips starting at a given page. We assume |
| 251 | * that the bbt bits are in consecutive order. |
| 252 | */ |
| 253 | static int read_abs_bbt(struct mtd_info *mtd, uint8_t *buf, struct nand_bbt_descr *td, int chip) |
| 254 | { |
| 255 | struct nand_chip *this = mtd->priv; |
| 256 | int res = 0, i; |
| 257 | |
| 258 | if (td->options & NAND_BBT_PERCHIP) { |
| 259 | int offs = 0; |
| 260 | for (i = 0; i < this->numchips; i++) { |
| 261 | if (chip == -1 || chip == i) |
| 262 | res = read_bbt(mtd, buf, td->pages[i], |
| 263 | this->chipsize >> this->bbt_erase_shift, |
| 264 | td, offs); |
| 265 | if (res) |
| 266 | return res; |
| 267 | offs += this->chipsize >> (this->bbt_erase_shift + 2); |
| 268 | } |
| 269 | } else { |
| 270 | res = read_bbt(mtd, buf, td->pages[0], |
| 271 | mtd->size >> this->bbt_erase_shift, td, 0); |
| 272 | if (res) |
| 273 | return res; |
| 274 | } |
| 275 | return 0; |
| 276 | } |
| 277 | |
| 278 | /* BBT marker is in the first page, no OOB */ |
| 279 | static int scan_read_data(struct mtd_info *mtd, uint8_t *buf, loff_t offs, |
| 280 | struct nand_bbt_descr *td) |
| 281 | { |
| 282 | size_t retlen; |
| 283 | size_t len; |
| 284 | |
| 285 | len = td->len; |
| 286 | if (td->options & NAND_BBT_VERSION) |
| 287 | len++; |
| 288 | |
| 289 | return mtd_read(mtd, offs, len, &retlen, buf); |
| 290 | } |
| 291 | |
| 292 | /** |
| 293 | * scan_read_oob - [GENERIC] Scan data+OOB region to buffer |
| 294 | * @mtd: MTD device structure |
| 295 | * @buf: temporary buffer |
| 296 | * @offs: offset at which to scan |
| 297 | * @len: length of data region to read |
| 298 | * |
| 299 | * Scan read data from data+OOB. May traverse multiple pages, interleaving |
| 300 | * page,OOB,page,OOB,... in buf. Completes transfer and returns the "strongest" |
| 301 | * ECC condition (error or bitflip). May quit on the first (non-ECC) error. |
| 302 | */ |
| 303 | static int scan_read_oob(struct mtd_info *mtd, uint8_t *buf, loff_t offs, |
| 304 | size_t len) |
| 305 | { |
| 306 | struct mtd_oob_ops ops; |
| 307 | int res, ret = 0; |
| 308 | |
| 309 | ops.mode = MTD_OPS_PLACE_OOB; |
| 310 | ops.ooboffs = 0; |
| 311 | ops.ooblen = mtd->oobsize; |
| 312 | |
| 313 | while (len > 0) { |
| 314 | ops.datbuf = buf; |
| 315 | ops.len = min(len, (size_t)mtd->writesize); |
| 316 | ops.oobbuf = buf + ops.len; |
| 317 | |
| 318 | res = mtd_read_oob(mtd, offs, &ops); |
| 319 | if (res) { |
| 320 | if (!mtd_is_bitflip_or_eccerr(res)) |
| 321 | return res; |
| 322 | else if (mtd_is_eccerr(res) || !ret) |
| 323 | ret = res; |
| 324 | } |
| 325 | |
| 326 | buf += mtd->oobsize + mtd->writesize; |
| 327 | len -= mtd->writesize; |
| 328 | offs += mtd->writesize; |
| 329 | } |
| 330 | return ret; |
| 331 | } |
| 332 | |
| 333 | static int scan_read(struct mtd_info *mtd, uint8_t *buf, loff_t offs, |
| 334 | size_t len, struct nand_bbt_descr *td) |
| 335 | { |
| 336 | if (td->options & NAND_BBT_NO_OOB) |
| 337 | return scan_read_data(mtd, buf, offs, td); |
| 338 | else |
| 339 | return scan_read_oob(mtd, buf, offs, len); |
| 340 | } |
| 341 | |
| 342 | /* Scan write data with oob to flash */ |
| 343 | static int scan_write_bbt(struct mtd_info *mtd, loff_t offs, size_t len, |
| 344 | uint8_t *buf, uint8_t *oob) |
| 345 | { |
| 346 | struct mtd_oob_ops ops; |
| 347 | |
| 348 | ops.mode = MTD_OPS_PLACE_OOB; |
| 349 | ops.ooboffs = 0; |
| 350 | ops.ooblen = mtd->oobsize; |
| 351 | ops.datbuf = buf; |
| 352 | ops.oobbuf = oob; |
| 353 | ops.len = len; |
| 354 | |
| 355 | return mtd_write_oob(mtd, offs, &ops); |
| 356 | } |
| 357 | |
| 358 | static u32 bbt_get_ver_offs(struct mtd_info *mtd, struct nand_bbt_descr *td) |
| 359 | { |
| 360 | u32 ver_offs = td->veroffs; |
| 361 | |
| 362 | if (!(td->options & NAND_BBT_NO_OOB)) |
| 363 | ver_offs += mtd->writesize; |
| 364 | return ver_offs; |
| 365 | } |
| 366 | |
| 367 | /** |
| 368 | * read_abs_bbts - [GENERIC] Read the bad block table(s) for all chips starting at a given page |
| 369 | * @mtd: MTD device structure |
| 370 | * @buf: temporary buffer |
| 371 | * @td: descriptor for the bad block table |
| 372 | * @md: descriptor for the bad block table mirror |
| 373 | * |
| 374 | * Read the bad block table(s) for all chips starting at a given page. We |
| 375 | * assume that the bbt bits are in consecutive order. |
| 376 | */ |
| 377 | static void read_abs_bbts(struct mtd_info *mtd, uint8_t *buf, |
| 378 | struct nand_bbt_descr *td, struct nand_bbt_descr *md) |
| 379 | { |
| 380 | struct nand_chip *this = mtd->priv; |
| 381 | |
| 382 | /* Read the primary version, if available */ |
| 383 | if (td->options & NAND_BBT_VERSION) { |
| 384 | scan_read(mtd, buf, (loff_t)td->pages[0] << this->page_shift, |
| 385 | mtd->writesize, td); |
| 386 | td->version[0] = buf[bbt_get_ver_offs(mtd, td)]; |
| 387 | pr_info("Bad block table at page %d, version 0x%02X\n", |
| 388 | td->pages[0], td->version[0]); |
| 389 | } |
| 390 | |
| 391 | /* Read the mirror version, if available */ |
| 392 | if (md && (md->options & NAND_BBT_VERSION)) { |
| 393 | scan_read(mtd, buf, (loff_t)md->pages[0] << this->page_shift, |
| 394 | mtd->writesize, md); |
| 395 | md->version[0] = buf[bbt_get_ver_offs(mtd, md)]; |
| 396 | pr_info("Bad block table at page %d, version 0x%02X\n", |
| 397 | md->pages[0], md->version[0]); |
| 398 | } |
| 399 | } |
| 400 | |
| 401 | /* Scan a given block full */ |
| 402 | static int scan_block_full(struct mtd_info *mtd, struct nand_bbt_descr *bd, |
| 403 | loff_t offs, uint8_t *buf, size_t readlen, |
| 404 | int scanlen, int len) |
| 405 | { |
| 406 | int ret, j; |
| 407 | |
| 408 | ret = scan_read_oob(mtd, buf, offs, readlen); |
| 409 | /* Ignore ECC errors when checking for BBM */ |
| 410 | if (ret && !mtd_is_bitflip_or_eccerr(ret)) |
| 411 | return ret; |
| 412 | |
| 413 | for (j = 0; j < len; j++, buf += scanlen) { |
| 414 | if (check_pattern(buf, scanlen, mtd->writesize, bd)) |
| 415 | return 1; |
| 416 | } |
| 417 | return 0; |
| 418 | } |
| 419 | |
| 420 | /* Scan a given block partially */ |
| 421 | static int scan_block_fast(struct mtd_info *mtd, struct nand_bbt_descr *bd, |
| 422 | loff_t offs, uint8_t *buf, int len) |
| 423 | { |
| 424 | struct mtd_oob_ops ops; |
| 425 | int j, ret; |
| 426 | |
| 427 | ops.ooblen = mtd->oobsize; |
| 428 | ops.oobbuf = buf; |
| 429 | ops.ooboffs = 0; |
| 430 | ops.datbuf = NULL; |
| 431 | ops.mode = MTD_OPS_PLACE_OOB; |
| 432 | |
| 433 | for (j = 0; j < len; j++) { |
| 434 | /* |
| 435 | * Read the full oob until read_oob is fixed to handle single |
| 436 | * byte reads for 16 bit buswidth. |
| 437 | */ |
| 438 | ret = mtd_read_oob(mtd, offs, &ops); |
| 439 | /* Ignore ECC errors when checking for BBM */ |
| 440 | if (ret && !mtd_is_bitflip_or_eccerr(ret)) |
| 441 | return ret; |
| 442 | |
| 443 | if (check_short_pattern(buf, bd)) |
| 444 | return 1; |
| 445 | |
| 446 | offs += mtd->writesize; |
| 447 | } |
| 448 | return 0; |
| 449 | } |
| 450 | |
| 451 | /** |
| 452 | * create_bbt - [GENERIC] Create a bad block table by scanning the device |
| 453 | * @mtd: MTD device structure |
| 454 | * @buf: temporary buffer |
| 455 | * @bd: descriptor for the good/bad block search pattern |
| 456 | * @chip: create the table for a specific chip, -1 read all chips; applies only |
| 457 | * if NAND_BBT_PERCHIP option is set |
| 458 | * |
| 459 | * Create a bad block table by scanning the device for the given good/bad block |
| 460 | * identify pattern. |
| 461 | */ |
| 462 | static int create_bbt(struct mtd_info *mtd, uint8_t *buf, |
| 463 | struct nand_bbt_descr *bd, int chip) |
| 464 | { |
| 465 | struct nand_chip *this = mtd->priv; |
| 466 | int i, numblocks, len, scanlen; |
| 467 | int startblock; |
| 468 | loff_t from; |
| 469 | size_t readlen; |
| 470 | |
| 471 | pr_info("Scanning device for bad blocks\n"); |
| 472 | |
| 473 | if (bd->options & NAND_BBT_SCANALLPAGES) |
| 474 | len = 1 << (this->bbt_erase_shift - this->page_shift); |
| 475 | else if (bd->options & NAND_BBT_SCAN2NDPAGE) |
| 476 | len = 2; |
| 477 | else |
| 478 | len = 1; |
| 479 | |
| 480 | if (!(bd->options & NAND_BBT_SCANEMPTY)) { |
| 481 | /* We need only read few bytes from the OOB area */ |
| 482 | scanlen = 0; |
| 483 | readlen = bd->len; |
| 484 | } else { |
| 485 | /* Full page content should be read */ |
| 486 | scanlen = mtd->writesize + mtd->oobsize; |
| 487 | readlen = len * mtd->writesize; |
| 488 | } |
| 489 | |
| 490 | if (chip == -1) { |
| 491 | /* |
| 492 | * Note that numblocks is 2 * (real numblocks) here, see i+=2 |
| 493 | * below as it makes shifting and masking less painful |
| 494 | */ |
| 495 | numblocks = mtd->size >> (this->bbt_erase_shift - 1); |
| 496 | startblock = 0; |
| 497 | from = 0; |
| 498 | } else { |
| 499 | if (chip >= this->numchips) { |
| 500 | pr_warn("create_bbt(): chipnr (%d) > available chips (%d)\n", |
| 501 | chip + 1, this->numchips); |
| 502 | return -EINVAL; |
| 503 | } |
| 504 | numblocks = this->chipsize >> (this->bbt_erase_shift - 1); |
| 505 | startblock = chip * numblocks; |
| 506 | numblocks += startblock; |
| 507 | from = (loff_t)startblock << (this->bbt_erase_shift - 1); |
| 508 | } |
| 509 | |
| 510 | if (this->bbt_options & NAND_BBT_SCANLASTPAGE) |
| 511 | from += mtd->erasesize - (mtd->writesize * len); |
| 512 | |
| 513 | for (i = startblock; i < numblocks;) { |
| 514 | int ret; |
| 515 | |
| 516 | BUG_ON(bd->options & NAND_BBT_NO_OOB); |
| 517 | |
| 518 | if (bd->options & NAND_BBT_SCANALLPAGES) |
| 519 | ret = scan_block_full(mtd, bd, from, buf, readlen, |
| 520 | scanlen, len); |
| 521 | else |
| 522 | ret = scan_block_fast(mtd, bd, from, buf, len); |
| 523 | |
| 524 | if (ret < 0) |
| 525 | return ret; |
| 526 | |
| 527 | if (ret) { |
| 528 | this->bbt[i >> 3] |= 0x03 << (i & 0x6); |
| 529 | pr_warn("Bad eraseblock %d at 0x%012llx\n", |
| 530 | i >> 1, (unsigned long long)from); |
| 531 | mtd->ecc_stats.badblocks++; |
| 532 | } |
| 533 | |
| 534 | i += 2; |
| 535 | from += (1 << this->bbt_erase_shift); |
| 536 | } |
| 537 | return 0; |
| 538 | } |
| 539 | |
| 540 | /** |
| 541 | * search_bbt - [GENERIC] scan the device for a specific bad block table |
| 542 | * @mtd: MTD device structure |
| 543 | * @buf: temporary buffer |
| 544 | * @td: descriptor for the bad block table |
| 545 | * |
| 546 | * Read the bad block table by searching for a given ident pattern. Search is |
| 547 | * preformed either from the beginning up or from the end of the device |
| 548 | * downwards. The search starts always at the start of a block. If the option |
| 549 | * NAND_BBT_PERCHIP is given, each chip is searched for a bbt, which contains |
| 550 | * the bad block information of this chip. This is necessary to provide support |
| 551 | * for certain DOC devices. |
| 552 | * |
| 553 | * The bbt ident pattern resides in the oob area of the first page in a block. |
| 554 | */ |
| 555 | static int search_bbt(struct mtd_info *mtd, uint8_t *buf, struct nand_bbt_descr *td) |
| 556 | { |
| 557 | struct nand_chip *this = mtd->priv; |
| 558 | int i, chips; |
| 559 | int bits, startblock, block, dir; |
| 560 | int scanlen = mtd->writesize + mtd->oobsize; |
| 561 | int bbtblocks; |
| 562 | int blocktopage = this->bbt_erase_shift - this->page_shift; |
| 563 | |
| 564 | /* Search direction top -> down? */ |
| 565 | if (td->options & NAND_BBT_LASTBLOCK) { |
| 566 | startblock = (mtd->size >> this->bbt_erase_shift) - 1; |
| 567 | dir = -1; |
| 568 | } else { |
| 569 | startblock = 0; |
| 570 | dir = 1; |
| 571 | } |
| 572 | |
| 573 | /* Do we have a bbt per chip? */ |
| 574 | if (td->options & NAND_BBT_PERCHIP) { |
| 575 | chips = this->numchips; |
| 576 | bbtblocks = this->chipsize >> this->bbt_erase_shift; |
| 577 | startblock &= bbtblocks - 1; |
| 578 | } else { |
| 579 | chips = 1; |
| 580 | bbtblocks = mtd->size >> this->bbt_erase_shift; |
| 581 | } |
| 582 | |
| 583 | /* Number of bits for each erase block in the bbt */ |
| 584 | bits = td->options & NAND_BBT_NRBITS_MSK; |
| 585 | |
| 586 | for (i = 0; i < chips; i++) { |
| 587 | /* Reset version information */ |
| 588 | td->version[i] = 0; |
| 589 | td->pages[i] = -1; |
| 590 | /* Scan the maximum number of blocks */ |
| 591 | for (block = 0; block < td->maxblocks; block++) { |
| 592 | |
| 593 | int actblock = startblock + dir * block; |
| 594 | loff_t offs = (loff_t)actblock << this->bbt_erase_shift; |
| 595 | |
| 596 | /* Read first page */ |
| 597 | scan_read(mtd, buf, offs, mtd->writesize, td); |
| 598 | if (!check_pattern(buf, scanlen, mtd->writesize, td)) { |
| 599 | td->pages[i] = actblock << blocktopage; |
| 600 | if (td->options & NAND_BBT_VERSION) { |
| 601 | offs = bbt_get_ver_offs(mtd, td); |
| 602 | td->version[i] = buf[offs]; |
| 603 | } |
| 604 | break; |
| 605 | } |
| 606 | } |
| 607 | startblock += this->chipsize >> this->bbt_erase_shift; |
| 608 | } |
| 609 | /* Check, if we found a bbt for each requested chip */ |
| 610 | for (i = 0; i < chips; i++) { |
| 611 | if (td->pages[i] == -1) |
| 612 | pr_warn("Bad block table not found for chip %d\n", i); |
| 613 | else |
| 614 | pr_info("Bad block table found at page %d, version " |
| 615 | "0x%02X\n", td->pages[i], td->version[i]); |
| 616 | } |
| 617 | return 0; |
| 618 | } |
| 619 | |
| 620 | /** |
| 621 | * search_read_bbts - [GENERIC] scan the device for bad block table(s) |
| 622 | * @mtd: MTD device structure |
| 623 | * @buf: temporary buffer |
| 624 | * @td: descriptor for the bad block table |
| 625 | * @md: descriptor for the bad block table mirror |
| 626 | * |
| 627 | * Search and read the bad block table(s). |
| 628 | */ |
| 629 | static void search_read_bbts(struct mtd_info *mtd, uint8_t *buf, |
| 630 | struct nand_bbt_descr *td, |
| 631 | struct nand_bbt_descr *md) |
| 632 | { |
| 633 | /* Search the primary table */ |
| 634 | search_bbt(mtd, buf, td); |
| 635 | |
| 636 | /* Search the mirror table */ |
| 637 | if (md) |
| 638 | search_bbt(mtd, buf, md); |
| 639 | } |
| 640 | |
| 641 | /** |
| 642 | * write_bbt - [GENERIC] (Re)write the bad block table |
| 643 | * @mtd: MTD device structure |
| 644 | * @buf: temporary buffer |
| 645 | * @td: descriptor for the bad block table |
| 646 | * @md: descriptor for the bad block table mirror |
| 647 | * @chipsel: selector for a specific chip, -1 for all |
| 648 | * |
| 649 | * (Re)write the bad block table. |
| 650 | */ |
| 651 | static int write_bbt(struct mtd_info *mtd, uint8_t *buf, |
| 652 | struct nand_bbt_descr *td, struct nand_bbt_descr *md, |
| 653 | int chipsel) |
| 654 | { |
| 655 | struct nand_chip *this = mtd->priv; |
| 656 | struct erase_info einfo; |
| 657 | int i, j, res, chip = 0; |
| 658 | int bits, startblock, dir, page, offs, numblocks, sft, sftmsk; |
| 659 | int nrchips, bbtoffs, pageoffs, ooboffs; |
| 660 | uint8_t msk[4]; |
| 661 | uint8_t rcode = td->reserved_block_code; |
| 662 | size_t retlen, len = 0; |
| 663 | loff_t to; |
| 664 | struct mtd_oob_ops ops; |
| 665 | |
| 666 | ops.ooblen = mtd->oobsize; |
| 667 | ops.ooboffs = 0; |
| 668 | ops.datbuf = NULL; |
| 669 | ops.mode = MTD_OPS_PLACE_OOB; |
| 670 | |
| 671 | if (!rcode) |
| 672 | rcode = 0xff; |
| 673 | /* Write bad block table per chip rather than per device? */ |
| 674 | if (td->options & NAND_BBT_PERCHIP) { |
| 675 | numblocks = (int)(this->chipsize >> this->bbt_erase_shift); |
| 676 | /* Full device write or specific chip? */ |
| 677 | if (chipsel == -1) { |
| 678 | nrchips = this->numchips; |
| 679 | } else { |
| 680 | nrchips = chipsel + 1; |
| 681 | chip = chipsel; |
| 682 | } |
| 683 | } else { |
| 684 | numblocks = (int)(mtd->size >> this->bbt_erase_shift); |
| 685 | nrchips = 1; |
| 686 | } |
| 687 | |
| 688 | /* Loop through the chips */ |
| 689 | for (; chip < nrchips; chip++) { |
| 690 | /* |
| 691 | * There was already a version of the table, reuse the page |
| 692 | * This applies for absolute placement too, as we have the |
| 693 | * page nr. in td->pages. |
| 694 | */ |
| 695 | if (td->pages[chip] != -1) { |
| 696 | page = td->pages[chip]; |
| 697 | goto write; |
| 698 | } |
| 699 | |
| 700 | /* |
| 701 | * Automatic placement of the bad block table. Search direction |
| 702 | * top -> down? |
| 703 | */ |
| 704 | if (td->options & NAND_BBT_LASTBLOCK) { |
| 705 | startblock = numblocks * (chip + 1) - 1; |
| 706 | dir = -1; |
| 707 | } else { |
| 708 | startblock = chip * numblocks; |
| 709 | dir = 1; |
| 710 | } |
| 711 | |
| 712 | for (i = 0; i < td->maxblocks; i++) { |
| 713 | int block = startblock + dir * i; |
| 714 | /* Check, if the block is bad */ |
| 715 | switch ((this->bbt[block >> 2] >> |
| 716 | (2 * (block & 0x03))) & 0x03) { |
| 717 | case 0x01: |
| 718 | case 0x03: |
| 719 | continue; |
| 720 | } |
| 721 | page = block << |
| 722 | (this->bbt_erase_shift - this->page_shift); |
| 723 | /* Check, if the block is used by the mirror table */ |
| 724 | if (!md || md->pages[chip] != page) |
| 725 | goto write; |
| 726 | } |
| 727 | pr_err("No space left to write bad block table\n"); |
| 728 | return -ENOSPC; |
| 729 | write: |
| 730 | |
| 731 | /* Set up shift count and masks for the flash table */ |
| 732 | bits = td->options & NAND_BBT_NRBITS_MSK; |
| 733 | msk[2] = ~rcode; |
| 734 | switch (bits) { |
| 735 | case 1: sft = 3; sftmsk = 0x07; msk[0] = 0x00; msk[1] = 0x01; |
| 736 | msk[3] = 0x01; |
| 737 | break; |
| 738 | case 2: sft = 2; sftmsk = 0x06; msk[0] = 0x00; msk[1] = 0x01; |
| 739 | msk[3] = 0x03; |
| 740 | break; |
| 741 | case 4: sft = 1; sftmsk = 0x04; msk[0] = 0x00; msk[1] = 0x0C; |
| 742 | msk[3] = 0x0f; |
| 743 | break; |
| 744 | case 8: sft = 0; sftmsk = 0x00; msk[0] = 0x00; msk[1] = 0x0F; |
| 745 | msk[3] = 0xff; |
| 746 | break; |
| 747 | default: return -EINVAL; |
| 748 | } |
| 749 | |
| 750 | bbtoffs = chip * (numblocks >> 2); |
| 751 | |
| 752 | to = ((loff_t)page) << this->page_shift; |
| 753 | |
| 754 | /* Must we save the block contents? */ |
| 755 | if (td->options & NAND_BBT_SAVECONTENT) { |
| 756 | /* Make it block aligned */ |
| 757 | to &= ~((loff_t)((1 << this->bbt_erase_shift) - 1)); |
| 758 | len = 1 << this->bbt_erase_shift; |
| 759 | res = mtd_read(mtd, to, len, &retlen, buf); |
| 760 | if (res < 0) { |
| 761 | if (retlen != len) { |
| 762 | pr_info("nand_bbt: error reading block " |
| 763 | "for writing the bad block table\n"); |
| 764 | return res; |
| 765 | } |
| 766 | pr_warn("nand_bbt: ECC error while reading " |
| 767 | "block for writing bad block table\n"); |
| 768 | } |
| 769 | /* Read oob data */ |
| 770 | ops.ooblen = (len >> this->page_shift) * mtd->oobsize; |
| 771 | ops.oobbuf = &buf[len]; |
| 772 | res = mtd_read_oob(mtd, to + mtd->writesize, &ops); |
| 773 | if (res < 0 || ops.oobretlen != ops.ooblen) |
| 774 | goto outerr; |
| 775 | |
| 776 | /* Calc the byte offset in the buffer */ |
| 777 | pageoffs = page - (int)(to >> this->page_shift); |
| 778 | offs = pageoffs << this->page_shift; |
| 779 | /* Preset the bbt area with 0xff */ |
| 780 | memset(&buf[offs], 0xff, (size_t)(numblocks >> sft)); |
| 781 | ooboffs = len + (pageoffs * mtd->oobsize); |
| 782 | |
| 783 | } else if (td->options & NAND_BBT_NO_OOB) { |
| 784 | ooboffs = 0; |
| 785 | offs = td->len; |
| 786 | /* The version byte */ |
| 787 | if (td->options & NAND_BBT_VERSION) |
| 788 | offs++; |
| 789 | /* Calc length */ |
| 790 | len = (size_t)(numblocks >> sft); |
| 791 | len += offs; |
| 792 | /* Make it page aligned! */ |
| 793 | len = ALIGN(len, mtd->writesize); |
| 794 | /* Preset the buffer with 0xff */ |
| 795 | memset(buf, 0xff, len); |
| 796 | /* Pattern is located at the begin of first page */ |
| 797 | memcpy(buf, td->pattern, td->len); |
| 798 | } else { |
| 799 | /* Calc length */ |
| 800 | len = (size_t)(numblocks >> sft); |
| 801 | /* Make it page aligned! */ |
| 802 | len = ALIGN(len, mtd->writesize); |
| 803 | /* Preset the buffer with 0xff */ |
| 804 | memset(buf, 0xff, len + |
| 805 | (len >> this->page_shift)* mtd->oobsize); |
| 806 | offs = 0; |
| 807 | ooboffs = len; |
| 808 | /* Pattern is located in oob area of first page */ |
| 809 | memcpy(&buf[ooboffs + td->offs], td->pattern, td->len); |
| 810 | } |
| 811 | |
| 812 | if (td->options & NAND_BBT_VERSION) |
| 813 | buf[ooboffs + td->veroffs] = td->version[chip]; |
| 814 | |
| 815 | /* Walk through the memory table */ |
| 816 | for (i = 0; i < numblocks;) { |
| 817 | uint8_t dat; |
| 818 | dat = this->bbt[bbtoffs + (i >> 2)]; |
| 819 | for (j = 0; j < 4; j++, i++) { |
| 820 | int sftcnt = (i << (3 - sft)) & sftmsk; |
| 821 | /* Do not store the reserved bbt blocks! */ |
| 822 | buf[offs + (i >> sft)] &= |
| 823 | ~(msk[dat & 0x03] << sftcnt); |
| 824 | dat >>= 2; |
| 825 | } |
| 826 | } |
| 827 | |
| 828 | memset(&einfo, 0, sizeof(einfo)); |
| 829 | einfo.mtd = mtd; |
| 830 | einfo.addr = to; |
| 831 | einfo.len = 1 << this->bbt_erase_shift; |
| 832 | res = nand_erase_nand(mtd, &einfo, 1); |
| 833 | if (res < 0) |
| 834 | goto outerr; |
| 835 | |
| 836 | res = scan_write_bbt(mtd, to, len, buf, |
| 837 | td->options & NAND_BBT_NO_OOB ? NULL : |
| 838 | &buf[len]); |
| 839 | if (res < 0) |
| 840 | goto outerr; |
| 841 | |
| 842 | pr_info("Bad block table written to 0x%012llx, version 0x%02X\n", |
| 843 | (unsigned long long)to, td->version[chip]); |
| 844 | |
| 845 | /* Mark it as used */ |
| 846 | td->pages[chip] = page; |
| 847 | } |
| 848 | return 0; |
| 849 | |
| 850 | outerr: |
| 851 | pr_warn("nand_bbt: error while writing bad block table %d\n", res); |
| 852 | return res; |
| 853 | } |
| 854 | |
| 855 | /** |
| 856 | * nand_memory_bbt - [GENERIC] create a memory based bad block table |
| 857 | * @mtd: MTD device structure |
| 858 | * @bd: descriptor for the good/bad block search pattern |
| 859 | * |
| 860 | * The function creates a memory based bbt by scanning the device for |
| 861 | * manufacturer / software marked good / bad blocks. |
| 862 | */ |
| 863 | static inline int nand_memory_bbt(struct mtd_info *mtd, struct nand_bbt_descr *bd) |
| 864 | { |
| 865 | struct nand_chip *this = mtd->priv; |
| 866 | |
| 867 | bd->options &= ~NAND_BBT_SCANEMPTY; |
| 868 | return create_bbt(mtd, this->buffers->databuf, bd, -1); |
| 869 | } |
| 870 | |
| 871 | /** |
| 872 | * check_create - [GENERIC] create and write bbt(s) if necessary |
| 873 | * @mtd: MTD device structure |
| 874 | * @buf: temporary buffer |
| 875 | * @bd: descriptor for the good/bad block search pattern |
| 876 | * |
| 877 | * The function checks the results of the previous call to read_bbt and creates |
| 878 | * / updates the bbt(s) if necessary. Creation is necessary if no bbt was found |
| 879 | * for the chip/device. Update is necessary if one of the tables is missing or |
| 880 | * the version nr. of one table is less than the other. |
| 881 | */ |
| 882 | static int check_create(struct mtd_info *mtd, uint8_t *buf, struct nand_bbt_descr *bd) |
| 883 | { |
| 884 | int i, chips, writeops, create, chipsel, res, res2; |
| 885 | struct nand_chip *this = mtd->priv; |
| 886 | struct nand_bbt_descr *td = this->bbt_td; |
| 887 | struct nand_bbt_descr *md = this->bbt_md; |
| 888 | struct nand_bbt_descr *rd, *rd2; |
| 889 | |
| 890 | /* Do we have a bbt per chip? */ |
| 891 | if (td->options & NAND_BBT_PERCHIP) |
| 892 | chips = this->numchips; |
| 893 | else |
| 894 | chips = 1; |
| 895 | |
| 896 | for (i = 0; i < chips; i++) { |
| 897 | writeops = 0; |
| 898 | create = 0; |
| 899 | rd = NULL; |
| 900 | rd2 = NULL; |
| 901 | res = res2 = 0; |
| 902 | /* Per chip or per device? */ |
| 903 | chipsel = (td->options & NAND_BBT_PERCHIP) ? i : -1; |
| 904 | /* Mirrored table available? */ |
| 905 | if (md) { |
| 906 | if (td->pages[i] == -1 && md->pages[i] == -1) { |
| 907 | create = 1; |
| 908 | writeops = 0x03; |
| 909 | } else if (td->pages[i] == -1) { |
| 910 | rd = md; |
| 911 | writeops = 0x01; |
| 912 | } else if (md->pages[i] == -1) { |
| 913 | rd = td; |
| 914 | writeops = 0x02; |
| 915 | } else if (td->version[i] == md->version[i]) { |
| 916 | rd = td; |
| 917 | if (!(td->options & NAND_BBT_VERSION)) |
| 918 | rd2 = md; |
| 919 | } else if (((int8_t)(td->version[i] - md->version[i])) > 0) { |
| 920 | rd = td; |
| 921 | writeops = 0x02; |
| 922 | } else { |
| 923 | rd = md; |
| 924 | writeops = 0x01; |
| 925 | } |
| 926 | } else { |
| 927 | if (td->pages[i] == -1) { |
| 928 | create = 1; |
| 929 | writeops = 0x01; |
| 930 | } else { |
| 931 | rd = td; |
| 932 | } |
| 933 | } |
| 934 | |
| 935 | if (create) { |
| 936 | /* Create the bad block table by scanning the device? */ |
| 937 | if (!(td->options & NAND_BBT_CREATE)) |
| 938 | continue; |
| 939 | |
| 940 | /* Create the table in memory by scanning the chip(s) */ |
| 941 | if (!(this->bbt_options & NAND_BBT_CREATE_EMPTY)) |
| 942 | create_bbt(mtd, buf, bd, chipsel); |
| 943 | |
| 944 | td->version[i] = 1; |
| 945 | if (md) |
| 946 | md->version[i] = 1; |
| 947 | } |
| 948 | |
| 949 | /* Read back first? */ |
| 950 | if (rd) { |
| 951 | res = read_abs_bbt(mtd, buf, rd, chipsel); |
| 952 | if (mtd_is_eccerr(res)) { |
| 953 | /* Mark table as invalid */ |
| 954 | rd->pages[i] = -1; |
| 955 | rd->version[i] = 0; |
| 956 | i--; |
| 957 | continue; |
| 958 | } |
| 959 | } |
| 960 | /* If they weren't versioned, read both */ |
| 961 | if (rd2) { |
| 962 | res2 = read_abs_bbt(mtd, buf, rd2, chipsel); |
| 963 | if (mtd_is_eccerr(res2)) { |
| 964 | /* Mark table as invalid */ |
| 965 | rd2->pages[i] = -1; |
| 966 | rd2->version[i] = 0; |
| 967 | i--; |
| 968 | continue; |
| 969 | } |
| 970 | } |
| 971 | |
| 972 | /* Scrub the flash table(s)? */ |
| 973 | if (mtd_is_bitflip(res) || mtd_is_bitflip(res2)) |
| 974 | writeops = 0x03; |
| 975 | |
| 976 | /* Update version numbers before writing */ |
| 977 | if (md) { |
| 978 | td->version[i] = max(td->version[i], md->version[i]); |
| 979 | md->version[i] = td->version[i]; |
| 980 | } |
| 981 | |
| 982 | /* Write the bad block table to the device? */ |
| 983 | if ((writeops & 0x01) && (td->options & NAND_BBT_WRITE)) { |
| 984 | res = write_bbt(mtd, buf, td, md, chipsel); |
| 985 | if (res < 0) |
| 986 | return res; |
| 987 | } |
| 988 | |
| 989 | /* Write the mirror bad block table to the device? */ |
| 990 | if ((writeops & 0x02) && md && (md->options & NAND_BBT_WRITE)) { |
| 991 | res = write_bbt(mtd, buf, md, td, chipsel); |
| 992 | if (res < 0) |
| 993 | return res; |
| 994 | } |
| 995 | } |
| 996 | return 0; |
| 997 | } |
| 998 | |
| 999 | /** |
| 1000 | * mark_bbt_regions - [GENERIC] mark the bad block table regions |
| 1001 | * @mtd: MTD device structure |
| 1002 | * @td: bad block table descriptor |
| 1003 | * |
| 1004 | * The bad block table regions are marked as "bad" to prevent accidental |
| 1005 | * erasures / writes. The regions are identified by the mark 0x02. |
| 1006 | */ |
| 1007 | static void mark_bbt_region(struct mtd_info *mtd, struct nand_bbt_descr *td) |
| 1008 | { |
| 1009 | struct nand_chip *this = mtd->priv; |
| 1010 | int i, j, chips, block, nrblocks, update; |
| 1011 | uint8_t oldval, newval; |
| 1012 | |
| 1013 | /* Do we have a bbt per chip? */ |
| 1014 | if (td->options & NAND_BBT_PERCHIP) { |
| 1015 | chips = this->numchips; |
| 1016 | nrblocks = (int)(this->chipsize >> this->bbt_erase_shift); |
| 1017 | } else { |
| 1018 | chips = 1; |
| 1019 | nrblocks = (int)(mtd->size >> this->bbt_erase_shift); |
| 1020 | } |
| 1021 | |
| 1022 | for (i = 0; i < chips; i++) { |
| 1023 | if ((td->options & NAND_BBT_ABSPAGE) || |
| 1024 | !(td->options & NAND_BBT_WRITE)) { |
| 1025 | if (td->pages[i] == -1) |
| 1026 | continue; |
| 1027 | block = td->pages[i] >> (this->bbt_erase_shift - this->page_shift); |
| 1028 | block <<= 1; |
| 1029 | oldval = this->bbt[(block >> 3)]; |
| 1030 | newval = oldval | (0x2 << (block & 0x06)); |
| 1031 | this->bbt[(block >> 3)] = newval; |
| 1032 | if ((oldval != newval) && td->reserved_block_code) |
| 1033 | nand_update_bbt(mtd, (loff_t)block << (this->bbt_erase_shift - 1)); |
| 1034 | continue; |
| 1035 | } |
| 1036 | update = 0; |
| 1037 | if (td->options & NAND_BBT_LASTBLOCK) |
| 1038 | block = ((i + 1) * nrblocks) - td->maxblocks; |
| 1039 | else |
| 1040 | block = i * nrblocks; |
| 1041 | block <<= 1; |
| 1042 | for (j = 0; j < td->maxblocks; j++) { |
| 1043 | oldval = this->bbt[(block >> 3)]; |
| 1044 | newval = oldval | (0x2 << (block & 0x06)); |
| 1045 | this->bbt[(block >> 3)] = newval; |
| 1046 | if (oldval != newval) |
| 1047 | update = 1; |
| 1048 | block += 2; |
| 1049 | } |
| 1050 | /* |
| 1051 | * If we want reserved blocks to be recorded to flash, and some |
| 1052 | * new ones have been marked, then we need to update the stored |
| 1053 | * bbts. This should only happen once. |
| 1054 | */ |
| 1055 | if (update && td->reserved_block_code) |
| 1056 | nand_update_bbt(mtd, (loff_t)(block - 2) << (this->bbt_erase_shift - 1)); |
| 1057 | } |
| 1058 | } |
| 1059 | |
| 1060 | /** |
| 1061 | * verify_bbt_descr - verify the bad block description |
| 1062 | * @mtd: MTD device structure |
| 1063 | * @bd: the table to verify |
| 1064 | * |
| 1065 | * This functions performs a few sanity checks on the bad block description |
| 1066 | * table. |
| 1067 | */ |
| 1068 | static void verify_bbt_descr(struct mtd_info *mtd, struct nand_bbt_descr *bd) |
| 1069 | { |
| 1070 | struct nand_chip *this = mtd->priv; |
| 1071 | u32 pattern_len; |
| 1072 | u32 bits; |
| 1073 | u32 table_size; |
| 1074 | |
| 1075 | if (!bd) |
| 1076 | return; |
| 1077 | |
| 1078 | pattern_len = bd->len; |
| 1079 | bits = bd->options & NAND_BBT_NRBITS_MSK; |
| 1080 | |
| 1081 | BUG_ON((this->bbt_options & NAND_BBT_NO_OOB) && |
| 1082 | !(this->bbt_options & NAND_BBT_USE_FLASH)); |
| 1083 | BUG_ON(!bits); |
| 1084 | |
| 1085 | if (bd->options & NAND_BBT_VERSION) |
| 1086 | pattern_len++; |
| 1087 | |
| 1088 | if (bd->options & NAND_BBT_NO_OOB) { |
| 1089 | BUG_ON(!(this->bbt_options & NAND_BBT_USE_FLASH)); |
| 1090 | BUG_ON(!(this->bbt_options & NAND_BBT_NO_OOB)); |
| 1091 | BUG_ON(bd->offs); |
| 1092 | if (bd->options & NAND_BBT_VERSION) |
| 1093 | BUG_ON(bd->veroffs != bd->len); |
| 1094 | BUG_ON(bd->options & NAND_BBT_SAVECONTENT); |
| 1095 | } |
| 1096 | |
| 1097 | if (bd->options & NAND_BBT_PERCHIP) |
| 1098 | table_size = this->chipsize >> this->bbt_erase_shift; |
| 1099 | else |
| 1100 | table_size = mtd->size >> this->bbt_erase_shift; |
| 1101 | table_size >>= 3; |
| 1102 | table_size *= bits; |
| 1103 | if (bd->options & NAND_BBT_NO_OOB) |
| 1104 | table_size += pattern_len; |
| 1105 | BUG_ON(table_size > (1 << this->bbt_erase_shift)); |
| 1106 | } |
| 1107 | |
| 1108 | /** |
| 1109 | * nand_scan_bbt - [NAND Interface] scan, find, read and maybe create bad block table(s) |
| 1110 | * @mtd: MTD device structure |
| 1111 | * @bd: descriptor for the good/bad block search pattern |
| 1112 | * |
| 1113 | * The function checks, if a bad block table(s) is/are already available. If |
| 1114 | * not it scans the device for manufacturer marked good / bad blocks and writes |
| 1115 | * the bad block table(s) to the selected place. |
| 1116 | * |
| 1117 | * The bad block table memory is allocated here. It must be freed by calling |
| 1118 | * the nand_free_bbt function. |
| 1119 | */ |
| 1120 | int nand_scan_bbt(struct mtd_info *mtd, struct nand_bbt_descr *bd) |
| 1121 | { |
| 1122 | struct nand_chip *this = mtd->priv; |
| 1123 | int len, res = 0; |
| 1124 | uint8_t *buf; |
| 1125 | struct nand_bbt_descr *td = this->bbt_td; |
| 1126 | struct nand_bbt_descr *md = this->bbt_md; |
| 1127 | |
| 1128 | len = mtd->size >> (this->bbt_erase_shift + 2); |
| 1129 | /* |
| 1130 | * Allocate memory (2bit per block) and clear the memory bad block |
| 1131 | * table. |
| 1132 | */ |
| 1133 | this->bbt = kzalloc(len, GFP_KERNEL); |
| 1134 | if (!this->bbt) |
| 1135 | return -ENOMEM; |
| 1136 | |
| 1137 | /* |
| 1138 | * If no primary table decriptor is given, scan the device to build a |
| 1139 | * memory based bad block table. |
| 1140 | */ |
| 1141 | if (!td) { |
| 1142 | if ((res = nand_memory_bbt(mtd, bd))) { |
| 1143 | pr_err("nand_bbt: can't scan flash and build the RAM-based BBT\n"); |
| 1144 | kfree(this->bbt); |
| 1145 | this->bbt = NULL; |
| 1146 | } |
| 1147 | return res; |
| 1148 | } |
| 1149 | verify_bbt_descr(mtd, td); |
| 1150 | verify_bbt_descr(mtd, md); |
| 1151 | |
| 1152 | /* Allocate a temporary buffer for one eraseblock incl. oob */ |
| 1153 | len = (1 << this->bbt_erase_shift); |
| 1154 | len += (len >> this->page_shift) * mtd->oobsize; |
| 1155 | buf = vmalloc(len); |
| 1156 | if (!buf) { |
| 1157 | kfree(this->bbt); |
| 1158 | this->bbt = NULL; |
| 1159 | return -ENOMEM; |
| 1160 | } |
| 1161 | |
| 1162 | /* Is the bbt at a given page? */ |
| 1163 | if (td->options & NAND_BBT_ABSPAGE) { |
| 1164 | read_abs_bbts(mtd, buf, td, md); |
| 1165 | } else { |
| 1166 | /* Search the bad block table using a pattern in oob */ |
| 1167 | search_read_bbts(mtd, buf, td, md); |
| 1168 | } |
| 1169 | |
| 1170 | res = check_create(mtd, buf, bd); |
| 1171 | |
| 1172 | /* Prevent the bbt regions from erasing / writing */ |
| 1173 | mark_bbt_region(mtd, td); |
| 1174 | if (md) |
| 1175 | mark_bbt_region(mtd, md); |
| 1176 | |
| 1177 | vfree(buf); |
| 1178 | return res; |
| 1179 | } |
| 1180 | |
| 1181 | /** |
| 1182 | * nand_update_bbt - [NAND Interface] update bad block table(s) |
| 1183 | * @mtd: MTD device structure |
| 1184 | * @offs: the offset of the newly marked block |
| 1185 | * |
| 1186 | * The function updates the bad block table(s). |
| 1187 | */ |
| 1188 | int nand_update_bbt(struct mtd_info *mtd, loff_t offs) |
| 1189 | { |
| 1190 | struct nand_chip *this = mtd->priv; |
| 1191 | int len, res = 0; |
| 1192 | int chip, chipsel; |
| 1193 | uint8_t *buf; |
| 1194 | struct nand_bbt_descr *td = this->bbt_td; |
| 1195 | struct nand_bbt_descr *md = this->bbt_md; |
| 1196 | |
| 1197 | if (!this->bbt || !td) |
| 1198 | return -EINVAL; |
| 1199 | |
| 1200 | /* Allocate a temporary buffer for one eraseblock incl. oob */ |
| 1201 | len = (1 << this->bbt_erase_shift); |
| 1202 | len += (len >> this->page_shift) * mtd->oobsize; |
| 1203 | buf = kmalloc(len, GFP_KERNEL); |
| 1204 | if (!buf) |
| 1205 | return -ENOMEM; |
| 1206 | |
| 1207 | /* Do we have a bbt per chip? */ |
| 1208 | if (td->options & NAND_BBT_PERCHIP) { |
| 1209 | chip = (int)(offs >> this->chip_shift); |
| 1210 | chipsel = chip; |
| 1211 | } else { |
| 1212 | chip = 0; |
| 1213 | chipsel = -1; |
| 1214 | } |
| 1215 | |
| 1216 | td->version[chip]++; |
| 1217 | if (md) |
| 1218 | md->version[chip]++; |
| 1219 | |
| 1220 | /* Write the bad block table to the device? */ |
| 1221 | if (td->options & NAND_BBT_WRITE) { |
| 1222 | res = write_bbt(mtd, buf, td, md, chipsel); |
| 1223 | if (res < 0) |
| 1224 | goto out; |
| 1225 | } |
| 1226 | /* Write the mirror bad block table to the device? */ |
| 1227 | if (md && (md->options & NAND_BBT_WRITE)) { |
| 1228 | res = write_bbt(mtd, buf, md, td, chipsel); |
| 1229 | } |
| 1230 | |
| 1231 | out: |
| 1232 | kfree(buf); |
| 1233 | return res; |
| 1234 | } |
| 1235 | |
| 1236 | /* |
| 1237 | * Define some generic bad / good block scan pattern which are used |
| 1238 | * while scanning a device for factory marked good / bad blocks. |
| 1239 | */ |
| 1240 | static uint8_t scan_ff_pattern[] = { 0xff, 0xff }; |
| 1241 | |
| 1242 | static uint8_t scan_agand_pattern[] = { 0x1C, 0x71, 0xC7, 0x1C, 0x71, 0xC7 }; |
| 1243 | |
| 1244 | static struct nand_bbt_descr agand_flashbased = { |
| 1245 | .options = NAND_BBT_SCANEMPTY | NAND_BBT_SCANALLPAGES, |
| 1246 | .offs = 0x20, |
| 1247 | .len = 6, |
| 1248 | .pattern = scan_agand_pattern |
| 1249 | }; |
| 1250 | |
| 1251 | /* Generic flash bbt descriptors */ |
| 1252 | static uint8_t bbt_pattern[] = {'B', 'b', 't', '0' }; |
| 1253 | static uint8_t mirror_pattern[] = {'1', 't', 'b', 'B' }; |
| 1254 | |
| 1255 | static struct nand_bbt_descr bbt_main_descr = { |
| 1256 | .options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE |
| 1257 | | NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP, |
| 1258 | .offs = 8, |
| 1259 | .len = 4, |
| 1260 | .veroffs = 12, |
| 1261 | .maxblocks = 4, |
| 1262 | .pattern = bbt_pattern |
| 1263 | }; |
| 1264 | |
| 1265 | static struct nand_bbt_descr bbt_mirror_descr = { |
| 1266 | .options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE |
| 1267 | | NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP, |
| 1268 | .offs = 8, |
| 1269 | .len = 4, |
| 1270 | .veroffs = 12, |
| 1271 | .maxblocks = 4, |
| 1272 | .pattern = mirror_pattern |
| 1273 | }; |
| 1274 | |
| 1275 | static struct nand_bbt_descr bbt_main_no_oob_descr = { |
| 1276 | .options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE |
| 1277 | | NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP |
| 1278 | | NAND_BBT_NO_OOB, |
| 1279 | .len = 4, |
| 1280 | .veroffs = 4, |
| 1281 | .maxblocks = 4, |
| 1282 | .pattern = bbt_pattern |
| 1283 | }; |
| 1284 | |
| 1285 | static struct nand_bbt_descr bbt_mirror_no_oob_descr = { |
| 1286 | .options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE |
| 1287 | | NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP |
| 1288 | | NAND_BBT_NO_OOB, |
| 1289 | .len = 4, |
| 1290 | .veroffs = 4, |
| 1291 | .maxblocks = 4, |
| 1292 | .pattern = mirror_pattern |
| 1293 | }; |
| 1294 | |
| 1295 | #define BADBLOCK_SCAN_MASK (~NAND_BBT_NO_OOB) |
| 1296 | /** |
| 1297 | * nand_create_badblock_pattern - [INTERN] Creates a BBT descriptor structure |
| 1298 | * @this: NAND chip to create descriptor for |
| 1299 | * |
| 1300 | * This function allocates and initializes a nand_bbt_descr for BBM detection |
| 1301 | * based on the properties of @this. The new descriptor is stored in |
| 1302 | * this->badblock_pattern. Thus, this->badblock_pattern should be NULL when |
| 1303 | * passed to this function. |
| 1304 | */ |
| 1305 | static int nand_create_badblock_pattern(struct nand_chip *this) |
| 1306 | { |
| 1307 | struct nand_bbt_descr *bd; |
| 1308 | if (this->badblock_pattern) { |
| 1309 | pr_warn("Bad block pattern already allocated; not replacing\n"); |
| 1310 | return -EINVAL; |
| 1311 | } |
| 1312 | bd = kzalloc(sizeof(*bd), GFP_KERNEL); |
| 1313 | if (!bd) |
| 1314 | return -ENOMEM; |
| 1315 | bd->options = this->bbt_options & BADBLOCK_SCAN_MASK; |
| 1316 | bd->offs = this->badblockpos; |
| 1317 | bd->len = (this->options & NAND_BUSWIDTH_16) ? 2 : 1; |
| 1318 | bd->pattern = scan_ff_pattern; |
| 1319 | bd->options |= NAND_BBT_DYNAMICSTRUCT; |
| 1320 | this->badblock_pattern = bd; |
| 1321 | return 0; |
| 1322 | } |
| 1323 | |
| 1324 | /** |
| 1325 | * nand_default_bbt - [NAND Interface] Select a default bad block table for the device |
| 1326 | * @mtd: MTD device structure |
| 1327 | * |
| 1328 | * This function selects the default bad block table support for the device and |
| 1329 | * calls the nand_scan_bbt function. |
| 1330 | */ |
| 1331 | int nand_default_bbt(struct mtd_info *mtd) |
| 1332 | { |
| 1333 | struct nand_chip *this = mtd->priv; |
| 1334 | |
| 1335 | /* |
| 1336 | * Default for AG-AND. We must use a flash based bad block table as the |
| 1337 | * devices have factory marked _good_ blocks. Erasing those blocks |
| 1338 | * leads to loss of the good / bad information, so we _must_ store this |
| 1339 | * information in a good / bad table during startup. |
| 1340 | */ |
| 1341 | if (this->options & NAND_IS_AND) { |
| 1342 | /* Use the default pattern descriptors */ |
| 1343 | if (!this->bbt_td) { |
| 1344 | this->bbt_td = &bbt_main_descr; |
| 1345 | this->bbt_md = &bbt_mirror_descr; |
| 1346 | } |
| 1347 | this->bbt_options |= NAND_BBT_USE_FLASH; |
| 1348 | return nand_scan_bbt(mtd, &agand_flashbased); |
| 1349 | } |
| 1350 | |
| 1351 | /* Is a flash based bad block table requested? */ |
| 1352 | if (this->bbt_options & NAND_BBT_USE_FLASH) { |
| 1353 | /* Use the default pattern descriptors */ |
| 1354 | if (!this->bbt_td) { |
| 1355 | if (this->bbt_options & NAND_BBT_NO_OOB) { |
| 1356 | this->bbt_td = &bbt_main_no_oob_descr; |
| 1357 | this->bbt_md = &bbt_mirror_no_oob_descr; |
| 1358 | } else { |
| 1359 | this->bbt_td = &bbt_main_descr; |
| 1360 | this->bbt_md = &bbt_mirror_descr; |
| 1361 | } |
| 1362 | } |
| 1363 | } else { |
| 1364 | this->bbt_td = NULL; |
| 1365 | this->bbt_md = NULL; |
| 1366 | } |
| 1367 | |
| 1368 | if (!this->badblock_pattern) |
| 1369 | nand_create_badblock_pattern(this); |
| 1370 | |
| 1371 | return nand_scan_bbt(mtd, this->badblock_pattern); |
| 1372 | } |
| 1373 | |
| 1374 | /** |
| 1375 | * nand_isbad_bbt - [NAND Interface] Check if a block is bad |
| 1376 | * @mtd: MTD device structure |
| 1377 | * @offs: offset in the device |
| 1378 | * @allowbbt: allow access to bad block table region |
| 1379 | */ |
| 1380 | int nand_isbad_bbt(struct mtd_info *mtd, loff_t offs, int allowbbt) |
| 1381 | { |
| 1382 | struct nand_chip *this = mtd->priv; |
| 1383 | int block; |
| 1384 | uint8_t res; |
| 1385 | |
| 1386 | /* Get block number * 2 */ |
| 1387 | block = (int)(offs >> (this->bbt_erase_shift - 1)); |
| 1388 | res = (this->bbt[block >> 3] >> (block & 0x06)) & 0x03; |
| 1389 | |
| 1390 | pr_debug("nand_isbad_bbt(): bbt info for offs 0x%08x: " |
| 1391 | "(block %d) 0x%02x\n", |
| 1392 | (unsigned int)offs, block >> 1, res); |
| 1393 | |
| 1394 | switch ((int)res) { |
| 1395 | case 0x00: |
| 1396 | return 0; |
| 1397 | case 0x01: |
| 1398 | return 1; |
| 1399 | case 0x02: |
| 1400 | return allowbbt ? 0 : 1; |
| 1401 | } |
| 1402 | return 1; |
| 1403 | } |
| 1404 | |
| 1405 | EXPORT_SYMBOL(nand_scan_bbt); |
| 1406 | EXPORT_SYMBOL(nand_default_bbt); |