include/linux/mtd/mtd.h

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