1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (c) 2017 Free Electrons 4 * 5 * Authors: 6 * Boris Brezillon <boris.brezillon@free-electrons.com> 7 * Peter Pan <peterpandong@micron.com> 8 */ 9 10 #define pr_fmt(fmt) "nand: " fmt 11 12 #include <linux/module.h> 13 #include <linux/mtd/nand.h> 14 15 /** 16 * nanddev_isbad() - Check if a block is bad 17 * @nand: NAND device 18 * @pos: position pointing to the block we want to check 19 * 20 * Return: true if the block is bad, false otherwise. 21 */ 22 bool nanddev_isbad(struct nand_device *nand, const struct nand_pos *pos) 23 { 24 if (WARN_ONCE(mtd_expert_analysis_mode, mtd_expert_analysis_warning)) 25 return false; 26 27 if (nanddev_bbt_is_initialized(nand)) { 28 unsigned int entry; 29 int status; 30 31 entry = nanddev_bbt_pos_to_entry(nand, pos); 32 status = nanddev_bbt_get_block_status(nand, entry); 33 /* Lazy block status retrieval */ 34 if (status == NAND_BBT_BLOCK_STATUS_UNKNOWN) { 35 if (nand->ops->isbad(nand, pos)) 36 status = NAND_BBT_BLOCK_FACTORY_BAD; 37 else 38 status = NAND_BBT_BLOCK_GOOD; 39 40 nanddev_bbt_set_block_status(nand, entry, status); 41 } 42 43 if (status == NAND_BBT_BLOCK_WORN || 44 status == NAND_BBT_BLOCK_FACTORY_BAD) 45 return true; 46 47 return false; 48 } 49 50 return nand->ops->isbad(nand, pos); 51 } 52 EXPORT_SYMBOL_GPL(nanddev_isbad); 53 54 /** 55 * nanddev_markbad() - Mark a block as bad 56 * @nand: NAND device 57 * @pos: position of the block to mark bad 58 * 59 * Mark a block bad. This function is updating the BBT if available and 60 * calls the low-level markbad hook (nand->ops->markbad()). 61 * 62 * Return: 0 in case of success, a negative error code otherwise. 63 */ 64 int nanddev_markbad(struct nand_device *nand, const struct nand_pos *pos) 65 { 66 struct mtd_info *mtd = nanddev_to_mtd(nand); 67 unsigned int entry; 68 int ret = 0; 69 70 if (nanddev_isbad(nand, pos)) 71 return 0; 72 73 ret = nand->ops->markbad(nand, pos); 74 if (ret) 75 pr_warn("failed to write BBM to block @%llx (err = %d)\n", 76 nanddev_pos_to_offs(nand, pos), ret); 77 78 if (!nanddev_bbt_is_initialized(nand)) 79 goto out; 80 81 entry = nanddev_bbt_pos_to_entry(nand, pos); 82 ret = nanddev_bbt_set_block_status(nand, entry, NAND_BBT_BLOCK_WORN); 83 if (ret) 84 goto out; 85 86 ret = nanddev_bbt_update(nand); 87 88 out: 89 if (!ret) 90 mtd->ecc_stats.badblocks++; 91 92 return ret; 93 } 94 EXPORT_SYMBOL_GPL(nanddev_markbad); 95 96 /** 97 * nanddev_isreserved() - Check whether an eraseblock is reserved or not 98 * @nand: NAND device 99 * @pos: NAND position to test 100 * 101 * Checks whether the eraseblock pointed by @pos is reserved or not. 102 * 103 * Return: true if the eraseblock is reserved, false otherwise. 104 */ 105 bool nanddev_isreserved(struct nand_device *nand, const struct nand_pos *pos) 106 { 107 unsigned int entry; 108 int status; 109 110 if (!nanddev_bbt_is_initialized(nand)) 111 return false; 112 113 /* Return info from the table */ 114 entry = nanddev_bbt_pos_to_entry(nand, pos); 115 status = nanddev_bbt_get_block_status(nand, entry); 116 return status == NAND_BBT_BLOCK_RESERVED; 117 } 118 EXPORT_SYMBOL_GPL(nanddev_isreserved); 119 120 /** 121 * nanddev_erase() - Erase a NAND portion 122 * @nand: NAND device 123 * @pos: position of the block to erase 124 * 125 * Erases the block if it's not bad. 126 * 127 * Return: 0 in case of success, a negative error code otherwise. 128 */ 129 int nanddev_erase(struct nand_device *nand, const struct nand_pos *pos) 130 { 131 if (nanddev_isbad(nand, pos) || nanddev_isreserved(nand, pos)) { 132 pr_warn("attempt to erase a bad/reserved block @%llx\n", 133 nanddev_pos_to_offs(nand, pos)); 134 return -EIO; 135 } 136 137 return nand->ops->erase(nand, pos); 138 } 139 EXPORT_SYMBOL_GPL(nanddev_erase); 140 141 /** 142 * nanddev_mtd_erase() - Generic mtd->_erase() implementation for NAND devices 143 * @mtd: MTD device 144 * @einfo: erase request 145 * 146 * This is a simple mtd->_erase() implementation iterating over all blocks 147 * concerned by @einfo and calling nand->ops->erase() on each of them. 148 * 149 * Note that mtd->_erase should not be directly assigned to this helper, 150 * because there's no locking here. NAND specialized layers should instead 151 * implement there own wrapper around nanddev_mtd_erase() taking the 152 * appropriate lock before calling nanddev_mtd_erase(). 153 * 154 * Return: 0 in case of success, a negative error code otherwise. 155 */ 156 int nanddev_mtd_erase(struct mtd_info *mtd, struct erase_info *einfo) 157 { 158 struct nand_device *nand = mtd_to_nanddev(mtd); 159 struct nand_pos pos, last; 160 int ret; 161 162 nanddev_offs_to_pos(nand, einfo->addr, &pos); 163 nanddev_offs_to_pos(nand, einfo->addr + einfo->len - 1, &last); 164 while (nanddev_pos_cmp(&pos, &last) <= 0) { 165 ret = nanddev_erase(nand, &pos); 166 if (ret) { 167 einfo->fail_addr = nanddev_pos_to_offs(nand, &pos); 168 169 return ret; 170 } 171 172 nanddev_pos_next_eraseblock(nand, &pos); 173 } 174 175 return 0; 176 } 177 EXPORT_SYMBOL_GPL(nanddev_mtd_erase); 178 179 /** 180 * nanddev_mtd_max_bad_blocks() - Get the maximum number of bad eraseblock on 181 * a specific region of the NAND device 182 * @mtd: MTD device 183 * @offs: offset of the NAND region 184 * @len: length of the NAND region 185 * 186 * Default implementation for mtd->_max_bad_blocks(). Only works if 187 * nand->memorg.max_bad_eraseblocks_per_lun is > 0. 188 * 189 * Return: a positive number encoding the maximum number of eraseblocks on a 190 * portion of memory, a negative error code otherwise. 191 */ 192 int nanddev_mtd_max_bad_blocks(struct mtd_info *mtd, loff_t offs, size_t len) 193 { 194 struct nand_device *nand = mtd_to_nanddev(mtd); 195 struct nand_pos pos, end; 196 unsigned int max_bb = 0; 197 198 if (!nand->memorg.max_bad_eraseblocks_per_lun) 199 return -ENOTSUPP; 200 201 nanddev_offs_to_pos(nand, offs, &pos); 202 nanddev_offs_to_pos(nand, offs + len, &end); 203 204 for (nanddev_offs_to_pos(nand, offs, &pos); 205 nanddev_pos_cmp(&pos, &end) < 0; 206 nanddev_pos_next_lun(nand, &pos)) 207 max_bb += nand->memorg.max_bad_eraseblocks_per_lun; 208 209 return max_bb; 210 } 211 EXPORT_SYMBOL_GPL(nanddev_mtd_max_bad_blocks); 212 213 /** 214 * nanddev_get_ecc_engine() - Find and get a suitable ECC engine 215 * @nand: NAND device 216 */ 217 static int nanddev_get_ecc_engine(struct nand_device *nand) 218 { 219 int engine_type; 220 221 /* Read the user desires in terms of ECC engine/configuration */ 222 of_get_nand_ecc_user_config(nand); 223 224 engine_type = nand->ecc.user_conf.engine_type; 225 if (engine_type == NAND_ECC_ENGINE_TYPE_INVALID) 226 engine_type = nand->ecc.defaults.engine_type; 227 228 switch (engine_type) { 229 case NAND_ECC_ENGINE_TYPE_NONE: 230 return 0; 231 case NAND_ECC_ENGINE_TYPE_SOFT: 232 nand->ecc.engine = nand_ecc_get_sw_engine(nand); 233 break; 234 case NAND_ECC_ENGINE_TYPE_ON_DIE: 235 nand->ecc.engine = nand_ecc_get_on_die_hw_engine(nand); 236 break; 237 case NAND_ECC_ENGINE_TYPE_ON_HOST: 238 pr_err("On-host hardware ECC engines not supported yet\n"); 239 break; 240 default: 241 pr_err("Missing ECC engine type\n"); 242 } 243 244 if (!nand->ecc.engine) 245 return -EINVAL; 246 247 return 0; 248 } 249 250 /** 251 * nanddev_put_ecc_engine() - Dettach and put the in-use ECC engine 252 * @nand: NAND device 253 */ 254 static int nanddev_put_ecc_engine(struct nand_device *nand) 255 { 256 switch (nand->ecc.ctx.conf.engine_type) { 257 case NAND_ECC_ENGINE_TYPE_ON_HOST: 258 pr_err("On-host hardware ECC engines not supported yet\n"); 259 break; 260 case NAND_ECC_ENGINE_TYPE_NONE: 261 case NAND_ECC_ENGINE_TYPE_SOFT: 262 case NAND_ECC_ENGINE_TYPE_ON_DIE: 263 default: 264 break; 265 } 266 267 return 0; 268 } 269 270 /** 271 * nanddev_find_ecc_configuration() - Find a suitable ECC configuration 272 * @nand: NAND device 273 */ 274 static int nanddev_find_ecc_configuration(struct nand_device *nand) 275 { 276 int ret; 277 278 if (!nand->ecc.engine) 279 return -ENOTSUPP; 280 281 ret = nand_ecc_init_ctx(nand); 282 if (ret) 283 return ret; 284 285 if (!nand_ecc_is_strong_enough(nand)) 286 pr_warn("WARNING: %s: the ECC used on your system is too weak compared to the one required by the NAND chip\n", 287 nand->mtd.name); 288 289 return 0; 290 } 291 292 /** 293 * nanddev_ecc_engine_init() - Initialize an ECC engine for the chip 294 * @nand: NAND device 295 */ 296 int nanddev_ecc_engine_init(struct nand_device *nand) 297 { 298 int ret; 299 300 /* Look for the ECC engine to use */ 301 ret = nanddev_get_ecc_engine(nand); 302 if (ret) { 303 pr_err("No ECC engine found\n"); 304 return ret; 305 } 306 307 /* No ECC engine requested */ 308 if (!nand->ecc.engine) 309 return 0; 310 311 /* Configure the engine: balance user input and chip requirements */ 312 ret = nanddev_find_ecc_configuration(nand); 313 if (ret) { 314 pr_err("No suitable ECC configuration\n"); 315 nanddev_put_ecc_engine(nand); 316 317 return ret; 318 } 319 320 return 0; 321 } 322 EXPORT_SYMBOL_GPL(nanddev_ecc_engine_init); 323 324 /** 325 * nanddev_ecc_engine_cleanup() - Cleanup ECC engine initializations 326 * @nand: NAND device 327 */ 328 void nanddev_ecc_engine_cleanup(struct nand_device *nand) 329 { 330 if (nand->ecc.engine) 331 nand_ecc_cleanup_ctx(nand); 332 333 nanddev_put_ecc_engine(nand); 334 } 335 EXPORT_SYMBOL_GPL(nanddev_ecc_engine_cleanup); 336 337 /** 338 * nanddev_init() - Initialize a NAND device 339 * @nand: NAND device 340 * @ops: NAND device operations 341 * @owner: NAND device owner 342 * 343 * Initializes a NAND device object. Consistency checks are done on @ops and 344 * @nand->memorg. Also takes care of initializing the BBT. 345 * 346 * Return: 0 in case of success, a negative error code otherwise. 347 */ 348 int nanddev_init(struct nand_device *nand, const struct nand_ops *ops, 349 struct module *owner) 350 { 351 struct mtd_info *mtd = nanddev_to_mtd(nand); 352 struct nand_memory_organization *memorg = nanddev_get_memorg(nand); 353 354 if (!nand || !ops) 355 return -EINVAL; 356 357 if (!ops->erase || !ops->markbad || !ops->isbad) 358 return -EINVAL; 359 360 if (!memorg->bits_per_cell || !memorg->pagesize || 361 !memorg->pages_per_eraseblock || !memorg->eraseblocks_per_lun || 362 !memorg->planes_per_lun || !memorg->luns_per_target || 363 !memorg->ntargets) 364 return -EINVAL; 365 366 nand->rowconv.eraseblock_addr_shift = 367 fls(memorg->pages_per_eraseblock - 1); 368 nand->rowconv.lun_addr_shift = fls(memorg->eraseblocks_per_lun - 1) + 369 nand->rowconv.eraseblock_addr_shift; 370 371 nand->ops = ops; 372 373 mtd->type = memorg->bits_per_cell == 1 ? 374 MTD_NANDFLASH : MTD_MLCNANDFLASH; 375 mtd->flags = MTD_CAP_NANDFLASH; 376 mtd->erasesize = memorg->pagesize * memorg->pages_per_eraseblock; 377 mtd->writesize = memorg->pagesize; 378 mtd->writebufsize = memorg->pagesize; 379 mtd->oobsize = memorg->oobsize; 380 mtd->size = nanddev_size(nand); 381 mtd->owner = owner; 382 383 return nanddev_bbt_init(nand); 384 } 385 EXPORT_SYMBOL_GPL(nanddev_init); 386 387 /** 388 * nanddev_cleanup() - Release resources allocated in nanddev_init() 389 * @nand: NAND device 390 * 391 * Basically undoes what has been done in nanddev_init(). 392 */ 393 void nanddev_cleanup(struct nand_device *nand) 394 { 395 if (nanddev_bbt_is_initialized(nand)) 396 nanddev_bbt_cleanup(nand); 397 } 398 EXPORT_SYMBOL_GPL(nanddev_cleanup); 399 400 MODULE_DESCRIPTION("Generic NAND framework"); 401 MODULE_AUTHOR("Boris Brezillon <boris.brezillon@free-electrons.com>"); 402 MODULE_LICENSE("GPL v2"); 403