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 /* always use indirect access for 256-bit to preserve kernel stack */
 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 #define map_bankwidth_is_32(map) (map_bankwidth(map) == 32)
 133 #undef MAX_MAP_BANKWIDTH
 134 #define MAX_MAP_BANKWIDTH 32
 135 #else
 136 #define map_bankwidth_is_32(map) (0)
 137 #endif
 138
 139 #ifndef map_bankwidth
 140 #ifdef CONFIG_MTD
 141 #warning "No CONFIG_MTD_MAP_BANK_WIDTH_xx selected. No NOR chip support can work"
 142 #endif
 143 static inline int map_bankwidth(void *map)
 144 {
 145         BUG();
 146         return 0;
 147 }
 148 #define map_bankwidth_is_large(map) (0)
 149 #define map_words(map) (0)
 150 #define MAX_MAP_BANKWIDTH 1
 151 #endif
 152
 153 static inline int map_bankwidth_supported(int w)
 154 {
 155         switch (w) {
 156 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_1
 157         case 1:
 158 #endif
 159 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_2
 160         case 2:
 161 #endif
 162 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_4
 163         case 4:
 164 #endif
 165 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_8
 166         case 8:
 167 #endif
 168 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_16
 169         case 16:
 170 #endif
 171 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_32
 172         case 32:
 173 #endif
 174                 return 1;
 175
 176         default:
 177                 return 0;
 178         }
 179 }
 180
 181 #define MAX_MAP_LONGS (((MAX_MAP_BANKWIDTH * 8) + BITS_PER_LONG - 1) / BITS_PER_LONG)
 182
 183 typedef union {
 184         unsigned long x[MAX_MAP_LONGS];
 185 } map_word;
 186
 187 /* The map stuff is very simple. You fill in your struct map_info with
 188    a handful of routines for accessing the device, making sure they handle
 189    paging etc. correctly if your device needs it. Then you pass it off
 190    to a chip probe routine -- either JEDEC or CFI probe or both -- via
 191    do_map_probe(). If a chip is recognised, the probe code will invoke the
 192    appropriate chip driver (if present) and return a struct mtd_info.
 193    At which point, you fill in the mtd->module with your own module
 194    address, and register it with the MTD core code. Or you could partition
 195    it and register the partitions instead, or keep it for your own private
 196    use; whatever.
 197
 198    The mtd->priv field will point to the struct map_info, and any further
 199    private data required by the chip driver is linked from the
 200    mtd->priv->fldrv_priv field. This allows the map driver to get at
 201    the destructor function map->fldrv_destroy() when it's tired
 202    of living.
 203 */
 204
 205 struct map_info {
 206         const char *name;
 207         unsigned long size;
 208         resource_size_t phys;
 209 #define NO_XIP (-1UL)
 210
 211         void __iomem *virt;
 212         void *cached;
 213
 214         int swap; /* this mapping's byte-swapping requirement */
 215         int bankwidth; /* in octets. This isn't necessarily the width
 216                        of actual bus cycles -- it's the repeat interval
 217                       in bytes, before you are talking to the first chip again.
 218                       */
 219
 220 #ifdef CONFIG_MTD_COMPLEX_MAPPINGS
 221         map_word (*read)(struct map_info *, unsigned long);
 222         void (*copy_from)(struct map_info *, void *, unsigned long, ssize_t);
 223
 224         void (*write)(struct map_info *, const map_word, unsigned long);
 225         void (*copy_to)(struct map_info *, unsigned long, const void *, ssize_t);
 226
 227         /* We can perhaps put in 'point' and 'unpoint' methods, if we really
 228            want to enable XIP for non-linear mappings. Not yet though. */
 229 #endif
 230         /* It's possible for the map driver to use cached memory in its
 231            copy_from implementation (and _only_ with copy_from).  However,
 232            when the chip driver knows some flash area has changed contents,
 233            it will signal it to the map driver through this routine to let
 234            the map driver invalidate the corresponding cache as needed.
 235            If there is no cache to care about this can be set to NULL. */
 236         void (*inval_cache)(struct map_info *, unsigned long, ssize_t);
 237
 238         /* This will be called with 1 as parameter when the first map user
 239          * needs VPP, and called with 0 when the last user exits. The map
 240          * core maintains a reference counter, and assumes that VPP is a
 241          * global resource applying to all mapped flash chips on the system.
 242          */
 243         void (*set_vpp)(struct map_info *, int);
 244
 245         unsigned long pfow_base;
 246         unsigned long map_priv_1;
 247         unsigned long map_priv_2;
 248         struct device_node *device_node;
 249         void *fldrv_priv;
 250         struct mtd_chip_driver *fldrv;
 251 };
 252
 253 struct mtd_chip_driver {
 254         struct mtd_info *(*probe)(struct map_info *map);
 255         void (*destroy)(struct mtd_info *);
 256         struct module *module;
 257         char *name;
 258         struct list_head list;
 259 };
 260
 261 void register_mtd_chip_driver(struct mtd_chip_driver *);
 262 void unregister_mtd_chip_driver(struct mtd_chip_driver *);
 263
 264 struct mtd_info *do_map_probe(const char *name, struct map_info *map);
 265 void map_destroy(struct mtd_info *mtd);
 266
 267 #define ENABLE_VPP(map) do { if (map->set_vpp) map->set_vpp(map, 1); } while (0)
 268 #define DISABLE_VPP(map) do { if (map->set_vpp) map->set_vpp(map, 0); } while (0)
 269
 270 #define INVALIDATE_CACHED_RANGE(map, from, size) \
 271         do { if (map->inval_cache) map->inval_cache(map, from, size); } while (0)
 272
 273
 274 static inline int map_word_equal(struct map_info *map, map_word val1, map_word val2)
 275 {
 276         int i;
 277
 278         for (i = 0; i < map_words(map); i++) {
 279                 if (val1.x[i] != val2.x[i])
 280                         return 0;
 281         }
 282
 283         return 1;
 284 }
 285
 286 static inline map_word map_word_and(struct map_info *map, map_word val1, map_word val2)
 287 {
 288         map_word r;
 289         int i;
 290
 291         for (i = 0; i < map_words(map); i++)
 292                 r.x[i] = val1.x[i] & val2.x[i];
 293
 294         return r;
 295 }
 296
 297 static inline map_word map_word_clr(struct map_info *map, map_word val1, map_word val2)
 298 {
 299         map_word r;
 300         int i;
 301
 302         for (i = 0; i < map_words(map); i++)
 303                 r.x[i] = val1.x[i] & ~val2.x[i];
 304
 305         return r;
 306 }
 307
 308 static inline map_word map_word_or(struct map_info *map, map_word val1, map_word val2)
 309 {
 310         map_word r;
 311         int i;
 312
 313         for (i = 0; i < map_words(map); i++)
 314                 r.x[i] = val1.x[i] | val2.x[i];
 315
 316         return r;
 317 }
 318
 319 static inline int map_word_andequal(struct map_info *map, map_word val1, map_word val2, map_word val3)
 320 {
 321         int i;
 322
 323         for (i = 0; i < map_words(map); i++) {
 324                 if ((val1.x[i] & val2.x[i]) != val3.x[i])
 325                         return 0;
 326         }
 327
 328         return 1;
 329 }
 330
 331 static inline int map_word_bitsset(struct map_info *map, map_word val1, map_word val2)
 332 {
 333         int i;
 334
 335         for (i = 0; i < map_words(map); i++) {
 336                 if (val1.x[i] & val2.x[i])
 337                         return 1;
 338         }
 339
 340         return 0;
 341 }
 342
 343 static inline map_word map_word_load(struct map_info *map, const void *ptr)
 344 {
 345         map_word r;
 346
 347         if (map_bankwidth_is_1(map))
 348                 r.x[0] = *(unsigned char *)ptr;
 349         else if (map_bankwidth_is_2(map))
 350                 r.x[0] = get_unaligned((uint16_t *)ptr);
 351         else if (map_bankwidth_is_4(map))
 352                 r.x[0] = get_unaligned((uint32_t *)ptr);
 353 #if BITS_PER_LONG >= 64
 354         else if (map_bankwidth_is_8(map))
 355                 r.x[0] = get_unaligned((uint64_t *)ptr);
 356 #endif
 357         else if (map_bankwidth_is_large(map))
 358                 memcpy(r.x, ptr, map->bankwidth);
 359         else
 360                 BUG();
 361
 362         return r;
 363 }
 364
 365 static inline map_word map_word_load_partial(struct map_info *map, map_word orig, const unsigned char *buf, int start, int len)
 366 {
 367         int i;
 368
 369         if (map_bankwidth_is_large(map)) {
 370                 char *dest = (char *)&orig;
 371
 372                 memcpy(dest+start, buf, len);
 373         } else {
 374                 for (i = start; i < start+len; i++) {
 375                         int bitpos;
 376
 377 #ifdef __LITTLE_ENDIAN
 378                         bitpos = i * 8;
 379 #else /* __BIG_ENDIAN */
 380                         bitpos = (map_bankwidth(map) - 1 - i) * 8;
 381 #endif
 382                         orig.x[0] &= ~(0xff << bitpos);
 383                         orig.x[0] |= (unsigned long)buf[i-start] << bitpos;
 384                 }
 385         }
 386         return orig;
 387 }
 388
 389 #if BITS_PER_LONG < 64
 390 #define MAP_FF_LIMIT 4
 391 #else
 392 #define MAP_FF_LIMIT 8
 393 #endif
 394
 395 static inline map_word map_word_ff(struct map_info *map)
 396 {
 397         map_word r;
 398         int i;
 399
 400         if (map_bankwidth(map) < MAP_FF_LIMIT) {
 401                 int bw = 8 * map_bankwidth(map);
 402
 403                 r.x[0] = (1UL << bw) - 1;
 404         } else {
 405                 for (i = 0; i < map_words(map); i++)
 406                         r.x[i] = ~0UL;
 407         }
 408         return r;
 409 }
 410
 411 static inline map_word inline_map_read(struct map_info *map, unsigned long ofs)
 412 {
 413         map_word r;
 414
 415         if (map_bankwidth_is_1(map))
 416                 r.x[0] = __raw_readb(map->virt + ofs);
 417         else if (map_bankwidth_is_2(map))
 418                 r.x[0] = __raw_readw(map->virt + ofs);
 419         else if (map_bankwidth_is_4(map))
 420                 r.x[0] = __raw_readl(map->virt + ofs);
 421 #if BITS_PER_LONG >= 64
 422         else if (map_bankwidth_is_8(map))
 423                 r.x[0] = __raw_readq(map->virt + ofs);
 424 #endif
 425         else if (map_bankwidth_is_large(map))
 426                 memcpy_fromio(r.x, map->virt + ofs, map->bankwidth);
 427         else
 428                 BUG();
 429
 430         return r;
 431 }
 432
 433 static inline void inline_map_write(struct map_info *map, const map_word datum, unsigned long ofs)
 434 {
 435         if (map_bankwidth_is_1(map))
 436                 __raw_writeb(datum.x[0], map->virt + ofs);
 437         else if (map_bankwidth_is_2(map))
 438                 __raw_writew(datum.x[0], map->virt + ofs);
 439         else if (map_bankwidth_is_4(map))
 440                 __raw_writel(datum.x[0], map->virt + ofs);
 441 #if BITS_PER_LONG >= 64
 442         else if (map_bankwidth_is_8(map))
 443                 __raw_writeq(datum.x[0], map->virt + ofs);
 444 #endif
 445         else if (map_bankwidth_is_large(map))
 446                 memcpy_toio(map->virt+ofs, datum.x, map->bankwidth);
 447         else
 448                 BUG();
 449         mb();
 450 }
 451
 452 static inline void inline_map_copy_from(struct map_info *map, void *to, unsigned long from, ssize_t len)
 453 {
 454         if (map->cached)
 455                 memcpy(to, (char *)map->cached + from, len);
 456         else
 457                 memcpy_fromio(to, map->virt + from, len);
 458 }
 459
 460 static inline void inline_map_copy_to(struct map_info *map, unsigned long to, const void *from, ssize_t len)
 461 {
 462         memcpy_toio(map->virt + to, from, len);
 463 }
 464
 465 #ifdef CONFIG_MTD_COMPLEX_MAPPINGS
 466 #define map_read(map, ofs) (map)->read(map, ofs)
 467 #define map_copy_from(map, to, from, len) (map)->copy_from(map, to, from, len)
 468 #define map_write(map, datum, ofs) (map)->write(map, datum, ofs)
 469 #define map_copy_to(map, to, from, len) (map)->copy_to(map, to, from, len)
 470
 471 extern void simple_map_init(struct map_info *);
 472 #define map_is_linear(map) (map->phys != NO_XIP)
 473
 474 #else
 475 #define map_read(map, ofs) inline_map_read(map, ofs)
 476 #define map_copy_from(map, to, from, len) inline_map_copy_from(map, to, from, len)
 477 #define map_write(map, datum, ofs) inline_map_write(map, datum, ofs)
 478 #define map_copy_to(map, to, from, len) inline_map_copy_to(map, to, from, len)
 479
 480
 481 #define simple_map_init(map) BUG_ON(!map_bankwidth_supported((map)->bankwidth))
 482 #define map_is_linear(map) ({ (void)(map); 1; })
 483
 484 #endif /* !CONFIG_MTD_COMPLEX_MAPPINGS */
 485
 486 #endif /* __LINUX_MTD_MAP_H__ */