include/linux/mtd/map.h

   1 /*
   2  * Copyright © 2000-2010 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 /* Overhauled routines for dealing with different mmap regions of flash */
  21
  22 #ifndef __LINUX_MTD_MAP_H__
  23 #define __LINUX_MTD_MAP_H__
  24
  25 #include <linux/types.h>
  26 #include <linux/list.h>
  27 #include <linux/string.h>
  28 #include <linux/bug.h>
  29 #include <linux/kernel.h>
  30 #include <linux/io.h>
  31
  32 #include <asm/unaligned.h>
  33 #include <asm/barrier.h>
  34
  35 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_1
  36 #define map_bankwidth(map) 1
  37 #define map_bankwidth_is_1(map) (map_bankwidth(map) == 1)
  38 #define map_bankwidth_is_large(map) (0)
  39 #define map_words(map) (1)
  40 #define MAX_MAP_BANKWIDTH 1
  41 #else
  42 #define map_bankwidth_is_1(map) (0)
  43 #endif
  44
  45 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_2
  46 # ifdef map_bankwidth
  47 #  undef map_bankwidth
  48 #  define map_bankwidth(map) ((map)->bankwidth)
  49 # else
  50 #  define map_bankwidth(map) 2
  51 #  define map_bankwidth_is_large(map) (0)
  52 #  define map_words(map) (1)
  53 # endif
  54 #define map_bankwidth_is_2(map) (map_bankwidth(map) == 2)
  55 #undef MAX_MAP_BANKWIDTH
  56 #define MAX_MAP_BANKWIDTH 2
  57 #else
  58 #define map_bankwidth_is_2(map) (0)
  59 #endif
  60
  61 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_4
  62 # ifdef map_bankwidth
  63 #  undef map_bankwidth
  64 #  define map_bankwidth(map) ((map)->bankwidth)
  65 # else
  66 #  define map_bankwidth(map) 4
  67 #  define map_bankwidth_is_large(map) (0)
  68 #  define map_words(map) (1)
  69 # endif
  70 #define map_bankwidth_is_4(map) (map_bankwidth(map) == 4)
  71 #undef MAX_MAP_BANKWIDTH
  72 #define MAX_MAP_BANKWIDTH 4
  73 #else
  74 #define map_bankwidth_is_4(map) (0)
  75 #endif
  76
  77 /* ensure we never evaluate anything shorted than an unsigned long
  78  * to zero, and ensure we'll never miss the end of an comparison (bjd) */
  79
  80 #define map_calc_words(map) ((map_bankwidth(map) + (sizeof(unsigned long)-1)) / sizeof(unsigned long))
  81
  82 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_8
  83 # ifdef map_bankwidth
  84 #  undef map_bankwidth
  85 #  define map_bankwidth(map) ((map)->bankwidth)
  86 #  if BITS_PER_LONG < 64
  87 #   undef map_bankwidth_is_large
  88 #   define map_bankwidth_is_large(map) (map_bankwidth(map) > BITS_PER_LONG/8)
  89 #   undef map_words
  90 #   define map_words(map) map_calc_words(map)
  91 #  endif
  92 # else
  93 #  define map_bankwidth(map) 8
  94 #  define map_bankwidth_is_large(map) (BITS_PER_LONG < 64)
  95 #  define map_words(map) map_calc_words(map)
  96 # endif
  97 #define map_bankwidth_is_8(map) (map_bankwidth(map) == 8)
  98 #undef MAX_MAP_BANKWIDTH
  99 #define MAX_MAP_BANKWIDTH 8
 100 #else
 101 #define map_bankwidth_is_8(map) (0)
 102 #endif
 103
 104 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_16
 105 # ifdef map_bankwidth
 106 #  undef map_bankwidth
 107 #  define map_bankwidth(map) ((map)->bankwidth)
 108 #  undef map_bankwidth_is_large
 109 #  define map_bankwidth_is_large(map) (map_bankwidth(map) > BITS_PER_LONG/8)
 110 #  undef map_words
 111 #  define map_words(map) map_calc_words(map)
 112 # else
 113 #  define map_bankwidth(map) 16
 114 #  define map_bankwidth_is_large(map) (1)
 115 #  define map_words(map) map_calc_words(map)
 116 # endif
 117 #define map_bankwidth_is_16(map) (map_bankwidth(map) == 16)
 118 #undef MAX_MAP_BANKWIDTH
 119 #define MAX_MAP_BANKWIDTH 16
 120 #else
 121 #define map_bankwidth_is_16(map) (0)
 122 #endif
 123
 124 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_32
 125 # ifdef map_bankwidth
 126 #  undef map_bankwidth
 127 #  define map_bankwidth(map) ((map)->bankwidth)
 128 #  undef map_bankwidth_is_large
 129 #  define map_bankwidth_is_large(map) (map_bankwidth(map) > BITS_PER_LONG/8)
 130 #  undef map_words
 131 #  define map_words(map) map_calc_words(map)
 132 # else
 133 #  define map_bankwidth(map) 32
 134 #  define map_bankwidth_is_large(map) (1)
 135 #  define map_words(map) map_calc_words(map)
 136 # endif
 137 #define map_bankwidth_is_32(map) (map_bankwidth(map) == 32)
 138 #undef MAX_MAP_BANKWIDTH
 139 #define MAX_MAP_BANKWIDTH 32
 140 #else
 141 #define map_bankwidth_is_32(map) (0)
 142 #endif
 143
 144 #ifndef map_bankwidth
 145 #ifdef CONFIG_MTD
 146 #warning "No CONFIG_MTD_MAP_BANK_WIDTH_xx selected. No NOR chip support can work"
 147 #endif
 148 static inline int map_bankwidth(void *map)
 149 {
 150         BUG();
 151         return 0;
 152 }
 153 #define map_bankwidth_is_large(map) (0)
 154 #define map_words(map) (0)
 155 #define MAX_MAP_BANKWIDTH 1
 156 #endif
 157
 158 static inline int map_bankwidth_supported(int w)
 159 {
 160         switch (w) {
 161 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_1
 162         case 1:
 163 #endif
 164 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_2
 165         case 2:
 166 #endif
 167 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_4
 168         case 4:
 169 #endif
 170 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_8
 171         case 8:
 172 #endif
 173 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_16
 174         case 16:
 175 #endif
 176 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_32
 177         case 32:
 178 #endif
 179                 return 1;
 180
 181         default:
 182                 return 0;
 183         }
 184 }
 185
 186 #define MAX_MAP_LONGS (((MAX_MAP_BANKWIDTH * 8) + BITS_PER_LONG - 1) / BITS_PER_LONG)
 187
 188 typedef union {
 189         unsigned long x[MAX_MAP_LONGS];
 190 } map_word;
 191
 192 /* The map stuff is very simple. You fill in your struct map_info with
 193    a handful of routines for accessing the device, making sure they handle
 194    paging etc. correctly if your device needs it. Then you pass it off
 195    to a chip probe routine -- either JEDEC or CFI probe or both -- via
 196    do_map_probe(). If a chip is recognised, the probe code will invoke the
 197    appropriate chip driver (if present) and return a struct mtd_info.
 198    At which point, you fill in the mtd->module with your own module
 199    address, and register it with the MTD core code. Or you could partition
 200    it and register the partitions instead, or keep it for your own private
 201    use; whatever.
 202
 203    The mtd->priv field will point to the struct map_info, and any further
 204    private data required by the chip driver is linked from the
 205    mtd->priv->fldrv_priv field. This allows the map driver to get at
 206    the destructor function map->fldrv_destroy() when it's tired
 207    of living.
 208 */
 209
 210 struct map_info {
 211         const char *name;
 212         unsigned long size;
 213         resource_size_t phys;
 214 #define NO_XIP (-1UL)
 215
 216         void __iomem *virt;
 217         void *cached;
 218
 219         int swap; /* this mapping's byte-swapping requirement */
 220         int bankwidth; /* in octets. This isn't necessarily the width
 221                        of actual bus cycles -- it's the repeat interval
 222                       in bytes, before you are talking to the first chip again.
 223                       */
 224
 225 #ifdef CONFIG_MTD_COMPLEX_MAPPINGS
 226         map_word (*read)(struct map_info *, unsigned long);
 227         void (*copy_from)(struct map_info *, void *, unsigned long, ssize_t);
 228
 229         void (*write)(struct map_info *, const map_word, unsigned long);
 230         void (*copy_to)(struct map_info *, unsigned long, const void *, ssize_t);
 231
 232         /* We can perhaps put in 'point' and 'unpoint' methods, if we really
 233            want to enable XIP for non-linear mappings. Not yet though. */
 234 #endif
 235         /* It's possible for the map driver to use cached memory in its
 236            copy_from implementation (and _only_ with copy_from).  However,
 237            when the chip driver knows some flash area has changed contents,
 238            it will signal it to the map driver through this routine to let
 239            the map driver invalidate the corresponding cache as needed.
 240            If there is no cache to care about this can be set to NULL. */
 241         void (*inval_cache)(struct map_info *, unsigned long, ssize_t);
 242
 243         /* set_vpp() must handle being reentered -- enable, enable, disable
 244            must leave it enabled. */
 245         void (*set_vpp)(struct map_info *, int);
 246
 247         unsigned long pfow_base;
 248         unsigned long map_priv_1;
 249         unsigned long map_priv_2;
 250         struct device_node *device_node;
 251         void *fldrv_priv;
 252         struct mtd_chip_driver *fldrv;
 253 };
 254
 255 struct mtd_chip_driver {
 256         struct mtd_info *(*probe)(struct map_info *map);
 257         void (*destroy)(struct mtd_info *);
 258         struct module *module;
 259         char *name;
 260         struct list_head list;
 261 };
 262
 263 void register_mtd_chip_driver(struct mtd_chip_driver *);
 264 void unregister_mtd_chip_driver(struct mtd_chip_driver *);
 265
 266 struct mtd_info *do_map_probe(const char *name, struct map_info *map);
 267 void map_destroy(struct mtd_info *mtd);
 268
 269 #define ENABLE_VPP(map) do { if (map->set_vpp) map->set_vpp(map, 1); } while (0)
 270 #define DISABLE_VPP(map) do { if (map->set_vpp) map->set_vpp(map, 0); } while (0)
 271
 272 #define INVALIDATE_CACHED_RANGE(map, from, size) \
 273         do { if (map->inval_cache) map->inval_cache(map, from, size); } while (0)
 274
 275
 276 static inline int map_word_equal(struct map_info *map, map_word val1, map_word val2)
 277 {
 278         int i;
 279
 280         for (i = 0; i < map_words(map); i++) {
 281                 if (val1.x[i] != val2.x[i])
 282                         return 0;
 283         }
 284
 285         return 1;
 286 }
 287
 288 static inline map_word map_word_and(struct map_info *map, map_word val1, map_word val2)
 289 {
 290         map_word r;
 291         int i;
 292
 293         for (i = 0; i < map_words(map); i++)
 294                 r.x[i] = val1.x[i] & val2.x[i];
 295
 296         return r;
 297 }
 298
 299 static inline map_word map_word_clr(struct map_info *map, map_word val1, map_word val2)
 300 {
 301         map_word r;
 302         int i;
 303
 304         for (i = 0; i < map_words(map); i++)
 305                 r.x[i] = val1.x[i] & ~val2.x[i];
 306
 307         return r;
 308 }
 309
 310 static inline map_word map_word_or(struct map_info *map, map_word val1, map_word val2)
 311 {
 312         map_word r;
 313         int i;
 314
 315         for (i = 0; i < map_words(map); i++)
 316                 r.x[i] = val1.x[i] | val2.x[i];
 317
 318         return r;
 319 }
 320
 321 static inline int map_word_andequal(struct map_info *map, map_word val1, map_word val2, map_word val3)
 322 {
 323         int i;
 324
 325         for (i = 0; i < map_words(map); i++) {
 326                 if ((val1.x[i] & val2.x[i]) != val3.x[i])
 327                         return 0;
 328         }
 329
 330         return 1;
 331 }
 332
 333 static inline int map_word_bitsset(struct map_info *map, map_word val1, map_word val2)
 334 {
 335         int i;
 336
 337         for (i = 0; i < map_words(map); i++) {
 338                 if (val1.x[i] & val2.x[i])
 339                         return 1;
 340         }
 341
 342         return 0;
 343 }
 344
 345 static inline map_word map_word_load(struct map_info *map, const void *ptr)
 346 {
 347         map_word r;
 348
 349         if (map_bankwidth_is_1(map))
 350                 r.x[0] = *(unsigned char *)ptr;
 351         else if (map_bankwidth_is_2(map))
 352                 r.x[0] = get_unaligned((uint16_t *)ptr);
 353         else if (map_bankwidth_is_4(map))
 354                 r.x[0] = get_unaligned((uint32_t *)ptr);
 355 #if BITS_PER_LONG >= 64
 356         else if (map_bankwidth_is_8(map))
 357                 r.x[0] = get_unaligned((uint64_t *)ptr);
 358 #endif
 359         else if (map_bankwidth_is_large(map))
 360                 memcpy(r.x, ptr, map->bankwidth);
 361         else
 362                 BUG();
 363
 364         return r;
 365 }
 366
 367 static inline map_word map_word_load_partial(struct map_info *map, map_word orig, const unsigned char *buf, int start, int len)
 368 {
 369         int i;
 370
 371         if (map_bankwidth_is_large(map)) {
 372                 char *dest = (char *)&orig;
 373
 374                 memcpy(dest+start, buf, len);
 375         } else {
 376                 for (i = start; i < start+len; i++) {
 377                         int bitpos;
 378
 379 #ifdef __LITTLE_ENDIAN
 380                         bitpos = i * 8;
 381 #else /* __BIG_ENDIAN */
 382                         bitpos = (map_bankwidth(map) - 1 - i) * 8;
 383 #endif
 384                         orig.x[0] &= ~(0xff << bitpos);
 385                         orig.x[0] |= (unsigned long)buf[i-start] << bitpos;
 386                 }
 387         }
 388         return orig;
 389 }
 390
 391 #if BITS_PER_LONG < 64
 392 #define MAP_FF_LIMIT 4
 393 #else
 394 #define MAP_FF_LIMIT 8
 395 #endif
 396
 397 static inline map_word map_word_ff(struct map_info *map)
 398 {
 399         map_word r;
 400         int i;
 401
 402         if (map_bankwidth(map) < MAP_FF_LIMIT) {
 403                 int bw = 8 * map_bankwidth(map);
 404
 405                 r.x[0] = (1UL << bw) - 1;
 406         } else {
 407                 for (i = 0; i < map_words(map); i++)
 408                         r.x[i] = ~0UL;
 409         }
 410         return r;
 411 }
 412
 413 static inline map_word inline_map_read(struct map_info *map, unsigned long ofs)
 414 {
 415         map_word r;
 416
 417         if (map_bankwidth_is_1(map))
 418                 r.x[0] = __raw_readb(map->virt + ofs);
 419         else if (map_bankwidth_is_2(map))
 420                 r.x[0] = __raw_readw(map->virt + ofs);
 421         else if (map_bankwidth_is_4(map))
 422                 r.x[0] = __raw_readl(map->virt + ofs);
 423 #if BITS_PER_LONG >= 64
 424         else if (map_bankwidth_is_8(map))
 425                 r.x[0] = __raw_readq(map->virt + ofs);
 426 #endif
 427         else if (map_bankwidth_is_large(map))
 428                 memcpy_fromio(r.x, map->virt + ofs, map->bankwidth);
 429         else
 430                 BUG();
 431
 432         return r;
 433 }
 434
 435 static inline void inline_map_write(struct map_info *map, const map_word datum, unsigned long ofs)
 436 {
 437         if (map_bankwidth_is_1(map))
 438                 __raw_writeb(datum.x[0], map->virt + ofs);
 439         else if (map_bankwidth_is_2(map))
 440                 __raw_writew(datum.x[0], map->virt + ofs);
 441         else if (map_bankwidth_is_4(map))
 442                 __raw_writel(datum.x[0], map->virt + ofs);
 443 #if BITS_PER_LONG >= 64
 444         else if (map_bankwidth_is_8(map))
 445                 __raw_writeq(datum.x[0], map->virt + ofs);
 446 #endif
 447         else if (map_bankwidth_is_large(map))
 448                 memcpy_toio(map->virt+ofs, datum.x, map->bankwidth);
 449         else
 450                 BUG();
 451         mb();
 452 }
 453
 454 static inline void inline_map_copy_from(struct map_info *map, void *to, unsigned long from, ssize_t len)
 455 {
 456         if (map->cached)
 457                 memcpy(to, (char *)map->cached + from, len);
 458         else
 459                 memcpy_fromio(to, map->virt + from, len);
 460 }
 461
 462 static inline void inline_map_copy_to(struct map_info *map, unsigned long to, const void *from, ssize_t len)
 463 {
 464         memcpy_toio(map->virt + to, from, len);
 465 }
 466
 467 #ifdef CONFIG_MTD_COMPLEX_MAPPINGS
 468 #define map_read(map, ofs) (map)->read(map, ofs)
 469 #define map_copy_from(map, to, from, len) (map)->copy_from(map, to, from, len)
 470 #define map_write(map, datum, ofs) (map)->write(map, datum, ofs)
 471 #define map_copy_to(map, to, from, len) (map)->copy_to(map, to, from, len)
 472
 473 extern void simple_map_init(struct map_info *);
 474 #define map_is_linear(map) (map->phys != NO_XIP)
 475
 476 #else
 477 #define map_read(map, ofs) inline_map_read(map, ofs)
 478 #define map_copy_from(map, to, from, len) inline_map_copy_from(map, to, from, len)
 479 #define map_write(map, datum, ofs) inline_map_write(map, datum, ofs)
 480 #define map_copy_to(map, to, from, len) inline_map_copy_to(map, to, from, len)
 481
 482
 483 #define simple_map_init(map) BUG_ON(!map_bankwidth_supported((map)->bankwidth))
 484 #define map_is_linear(map) ({ (void)(map); 1; })
 485
 486 #endif /* !CONFIG_MTD_COMPLEX_MAPPINGS */
 487
 488 #endif /* __LINUX_MTD_MAP_H__ */