1 /* 2 * Copyright © 1999-2010 David Woodhouse <dwmw2@infradead.org> et al. 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License as published by 6 * the Free Software Foundation; either version 2 of the License, or 7 * (at your option) any later version. 8 * 9 * This program is distributed in the hope that it will be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 * GNU General Public License for more details. 13 * 14 * You should have received a copy of the GNU General Public License 15 * along with this program; if not, write to the Free Software 16 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 17 * 18 */ 19 20 #ifndef __MTD_MTD_H__ 21 #define __MTD_MTD_H__ 22 23 #include <linux/types.h> 24 #include <linux/uio.h> 25 #include <linux/notifier.h> 26 #include <linux/device.h> 27 28 #include <mtd/mtd-abi.h> 29 30 #include <asm/div64.h> 31 32 #define MTD_CHAR_MAJOR 90 33 #define MTD_BLOCK_MAJOR 31 34 35 #define MTD_ERASE_PENDING 0x01 36 #define MTD_ERASING 0x02 37 #define MTD_ERASE_SUSPEND 0x04 38 #define MTD_ERASE_DONE 0x08 39 #define MTD_ERASE_FAILED 0x10 40 41 #define MTD_FAIL_ADDR_UNKNOWN -1LL 42 43 /* 44 * If the erase fails, fail_addr might indicate exactly which block failed. If 45 * fail_addr = MTD_FAIL_ADDR_UNKNOWN, the failure was not at the device level 46 * or was not specific to any particular block. 47 */ 48 struct erase_info { 49 struct mtd_info *mtd; 50 uint64_t addr; 51 uint64_t len; 52 uint64_t fail_addr; 53 u_long time; 54 u_long retries; 55 unsigned dev; 56 unsigned cell; 57 void (*callback) (struct erase_info *self); 58 u_long priv; 59 u_char state; 60 struct erase_info *next; 61 }; 62 63 struct mtd_erase_region_info { 64 uint64_t offset; /* At which this region starts, from the beginning of the MTD */ 65 uint32_t erasesize; /* For this region */ 66 uint32_t numblocks; /* Number of blocks of erasesize in this region */ 67 unsigned long *lockmap; /* If keeping bitmap of locks */ 68 }; 69 70 /** 71 * struct mtd_oob_ops - oob operation operands 72 * @mode: operation mode 73 * 74 * @len: number of data bytes to write/read 75 * 76 * @retlen: number of data bytes written/read 77 * 78 * @ooblen: number of oob bytes to write/read 79 * @oobretlen: number of oob bytes written/read 80 * @ooboffs: offset of oob data in the oob area (only relevant when 81 * mode = MTD_OPS_PLACE_OOB or MTD_OPS_RAW) 82 * @datbuf: data buffer - if NULL only oob data are read/written 83 * @oobbuf: oob data buffer 84 * 85 * Note, it is allowed to read more than one OOB area at one go, but not write. 86 * The interface assumes that the OOB write requests program only one page's 87 * OOB area. 88 */ 89 struct mtd_oob_ops { 90 unsigned int mode; 91 size_t len; 92 size_t retlen; 93 size_t ooblen; 94 size_t oobretlen; 95 uint32_t ooboffs; 96 uint8_t *datbuf; 97 uint8_t *oobbuf; 98 }; 99 100 #define MTD_MAX_OOBFREE_ENTRIES_LARGE 32 101 #define MTD_MAX_ECCPOS_ENTRIES_LARGE 448 102 /* 103 * Internal ECC layout control structure. For historical reasons, there is a 104 * similar, smaller struct nand_ecclayout_user (in mtd-abi.h) that is retained 105 * for export to user-space via the ECCGETLAYOUT ioctl. 106 * nand_ecclayout should be expandable in the future simply by the above macros. 107 */ 108 struct nand_ecclayout { 109 __u32 eccbytes; 110 __u32 eccpos[MTD_MAX_ECCPOS_ENTRIES_LARGE]; 111 __u32 oobavail; 112 struct nand_oobfree oobfree[MTD_MAX_OOBFREE_ENTRIES_LARGE]; 113 }; 114 115 struct module; /* only needed for owner field in mtd_info */ 116 117 struct mtd_info { 118 u_char type; 119 uint32_t flags; 120 uint64_t size; // Total size of the MTD 121 122 /* "Major" erase size for the device. Naïve users may take this 123 * to be the only erase size available, or may use the more detailed 124 * information below if they desire 125 */ 126 uint32_t erasesize; 127 /* Minimal writable flash unit size. In case of NOR flash it is 1 (even 128 * though individual bits can be cleared), in case of NAND flash it is 129 * one NAND page (or half, or one-fourths of it), in case of ECC-ed NOR 130 * it is of ECC block size, etc. It is illegal to have writesize = 0. 131 * Any driver registering a struct mtd_info must ensure a writesize of 132 * 1 or larger. 133 */ 134 uint32_t writesize; 135 136 /* 137 * Size of the write buffer used by the MTD. MTD devices having a write 138 * buffer can write multiple writesize chunks at a time. E.g. while 139 * writing 4 * writesize bytes to a device with 2 * writesize bytes 140 * buffer the MTD driver can (but doesn't have to) do 2 writesize 141 * operations, but not 4. Currently, all NANDs have writebufsize 142 * equivalent to writesize (NAND page size). Some NOR flashes do have 143 * writebufsize greater than writesize. 144 */ 145 uint32_t writebufsize; 146 147 uint32_t oobsize; // Amount of OOB data per block (e.g. 16) 148 uint32_t oobavail; // Available OOB bytes per block 149 150 /* 151 * If erasesize is a power of 2 then the shift is stored in 152 * erasesize_shift otherwise erasesize_shift is zero. Ditto writesize. 153 */ 154 unsigned int erasesize_shift; 155 unsigned int writesize_shift; 156 /* Masks based on erasesize_shift and writesize_shift */ 157 unsigned int erasesize_mask; 158 unsigned int writesize_mask; 159 160 // Kernel-only stuff starts here. 161 const char *name; 162 int index; 163 164 /* ECC layout structure pointer - read only! */ 165 struct nand_ecclayout *ecclayout; 166 167 /* Data for variable erase regions. If numeraseregions is zero, 168 * it means that the whole device has erasesize as given above. 169 */ 170 int numeraseregions; 171 struct mtd_erase_region_info *eraseregions; 172 173 /* 174 * Erase is an asynchronous operation. Device drivers are supposed 175 * to call instr->callback() whenever the operation completes, even 176 * if it completes with a failure. 177 * Callers are supposed to pass a callback function and wait for it 178 * to be called before writing to the block. 179 */ 180 int (*erase) (struct mtd_info *mtd, struct erase_info *instr); 181 182 /* This stuff for eXecute-In-Place */ 183 /* phys is optional and may be set to NULL */ 184 int (*point) (struct mtd_info *mtd, loff_t from, size_t len, 185 size_t *retlen, void **virt, resource_size_t *phys); 186 187 /* We probably shouldn't allow XIP if the unpoint isn't a NULL */ 188 void (*unpoint) (struct mtd_info *mtd, loff_t from, size_t len); 189 190 /* Allow NOMMU mmap() to directly map the device (if not NULL) 191 * - return the address to which the offset maps 192 * - return -ENOSYS to indicate refusal to do the mapping 193 */ 194 unsigned long (*get_unmapped_area) (struct mtd_info *mtd, 195 unsigned long len, 196 unsigned long offset, 197 unsigned long flags); 198 199 /* Backing device capabilities for this device 200 * - provides mmap capabilities 201 */ 202 struct backing_dev_info *backing_dev_info; 203 204 205 int (*read) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf); 206 int (*write) (struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen, const u_char *buf); 207 208 /* In blackbox flight recorder like scenarios we want to make successful 209 writes in interrupt context. panic_write() is only intended to be 210 called when its known the kernel is about to panic and we need the 211 write to succeed. Since the kernel is not going to be running for much 212 longer, this function can break locks and delay to ensure the write 213 succeeds (but not sleep). */ 214 215 int (*panic_write) (struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen, const u_char *buf); 216 217 int (*read_oob) (struct mtd_info *mtd, loff_t from, 218 struct mtd_oob_ops *ops); 219 int (*write_oob) (struct mtd_info *mtd, loff_t to, 220 struct mtd_oob_ops *ops); 221 222 /* 223 * Methods to access the protection register area, present in some 224 * flash devices. The user data is one time programmable but the 225 * factory data is read only. 226 */ 227 int (*get_fact_prot_info) (struct mtd_info *mtd, struct otp_info *buf, size_t len); 228 int (*read_fact_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf); 229 int (*get_user_prot_info) (struct mtd_info *mtd, struct otp_info *buf, size_t len); 230 int (*read_user_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf); 231 int (*write_user_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf); 232 int (*lock_user_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len); 233 234 /* kvec-based read/write methods. 235 NB: The 'count' parameter is the number of _vectors_, each of 236 which contains an (ofs, len) tuple. 237 */ 238 int (*writev) (struct mtd_info *mtd, const struct kvec *vecs, unsigned long count, loff_t to, size_t *retlen); 239 240 /* Sync */ 241 void (*sync) (struct mtd_info *mtd); 242 243 /* Chip-supported device locking */ 244 int (*lock) (struct mtd_info *mtd, loff_t ofs, uint64_t len); 245 int (*unlock) (struct mtd_info *mtd, loff_t ofs, uint64_t len); 246 int (*is_locked) (struct mtd_info *mtd, loff_t ofs, uint64_t len); 247 248 /* Power Management functions */ 249 int (*suspend) (struct mtd_info *mtd); 250 void (*resume) (struct mtd_info *mtd); 251 252 /* Bad block management functions */ 253 int (*block_isbad) (struct mtd_info *mtd, loff_t ofs); 254 int (*block_markbad) (struct mtd_info *mtd, loff_t ofs); 255 256 struct notifier_block reboot_notifier; /* default mode before reboot */ 257 258 /* ECC status information */ 259 struct mtd_ecc_stats ecc_stats; 260 /* Subpage shift (NAND) */ 261 int subpage_sft; 262 263 void *priv; 264 265 struct module *owner; 266 struct device dev; 267 int usecount; 268 269 /* If the driver is something smart, like UBI, it may need to maintain 270 * its own reference counting. The below functions are only for driver. 271 * The driver may register its callbacks. These callbacks are not 272 * supposed to be called by MTD users */ 273 int (*get_device) (struct mtd_info *mtd); 274 void (*put_device) (struct mtd_info *mtd); 275 }; 276 277 static inline struct mtd_info *dev_to_mtd(struct device *dev) 278 { 279 return dev ? dev_get_drvdata(dev) : NULL; 280 } 281 282 static inline uint32_t mtd_div_by_eb(uint64_t sz, struct mtd_info *mtd) 283 { 284 if (mtd->erasesize_shift) 285 return sz >> mtd->erasesize_shift; 286 do_div(sz, mtd->erasesize); 287 return sz; 288 } 289 290 static inline uint32_t mtd_mod_by_eb(uint64_t sz, struct mtd_info *mtd) 291 { 292 if (mtd->erasesize_shift) 293 return sz & mtd->erasesize_mask; 294 return do_div(sz, mtd->erasesize); 295 } 296 297 static inline uint32_t mtd_div_by_ws(uint64_t sz, struct mtd_info *mtd) 298 { 299 if (mtd->writesize_shift) 300 return sz >> mtd->writesize_shift; 301 do_div(sz, mtd->writesize); 302 return sz; 303 } 304 305 static inline uint32_t mtd_mod_by_ws(uint64_t sz, struct mtd_info *mtd) 306 { 307 if (mtd->writesize_shift) 308 return sz & mtd->writesize_mask; 309 return do_div(sz, mtd->writesize); 310 } 311 312 /* Kernel-side ioctl definitions */ 313 314 struct mtd_partition; 315 struct mtd_part_parser_data; 316 317 extern int mtd_device_parse_register(struct mtd_info *mtd, 318 const char **part_probe_types, 319 struct mtd_part_parser_data *parser_data, 320 const struct mtd_partition *defparts, 321 int defnr_parts); 322 #define mtd_device_register(master, parts, nr_parts) \ 323 mtd_device_parse_register(master, NULL, NULL, parts, nr_parts) 324 extern int mtd_device_unregister(struct mtd_info *master); 325 extern struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num); 326 extern int __get_mtd_device(struct mtd_info *mtd); 327 extern void __put_mtd_device(struct mtd_info *mtd); 328 extern struct mtd_info *get_mtd_device_nm(const char *name); 329 extern void put_mtd_device(struct mtd_info *mtd); 330 331 332 struct mtd_notifier { 333 void (*add)(struct mtd_info *mtd); 334 void (*remove)(struct mtd_info *mtd); 335 struct list_head list; 336 }; 337 338 339 extern void register_mtd_user (struct mtd_notifier *new); 340 extern int unregister_mtd_user (struct mtd_notifier *old); 341 342 int default_mtd_writev(struct mtd_info *mtd, const struct kvec *vecs, 343 unsigned long count, loff_t to, size_t *retlen); 344 345 int default_mtd_readv(struct mtd_info *mtd, struct kvec *vecs, 346 unsigned long count, loff_t from, size_t *retlen); 347 348 void *mtd_kmalloc_up_to(const struct mtd_info *mtd, size_t *size); 349 350 void mtd_erase_callback(struct erase_info *instr); 351 352 static inline int mtd_is_bitflip(int err) { 353 return err == -EUCLEAN; 354 } 355 356 static inline int mtd_is_eccerr(int err) { 357 return err == -EBADMSG; 358 } 359 360 static inline int mtd_is_bitflip_or_eccerr(int err) { 361 return mtd_is_bitflip(err) || mtd_is_eccerr(err); 362 } 363 364 #endif /* __MTD_MTD_H__ */ 365