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         /* This will be called with 1 as parameter when the first map user
 244          * needs VPP, and called with 0 when the last user exits. The map
 245          * core maintains a reference counter, and assumes that VPP is a
 246          * global resource applying to all mapped flash chips on the system.
 247          */
 248         void (*set_vpp)(struct map_info *, int);
 249
 250         unsigned long pfow_base;
 251         unsigned long map_priv_1;
 252         unsigned long map_priv_2;
 253         struct device_node *device_node;
 254         void *fldrv_priv;
 255         struct mtd_chip_driver *fldrv;
 256 };
 257
 258 struct mtd_chip_driver {
 259         struct mtd_info *(*probe)(struct map_info *map);
 260         void (*destroy)(struct mtd_info *);
 261         struct module *module;
 262         char *name;
 263         struct list_head list;
 264 };
 265
 266 void register_mtd_chip_driver(struct mtd_chip_driver *);
 267 void unregister_mtd_chip_driver(struct mtd_chip_driver *);
 268
 269 struct mtd_info *do_map_probe(const char *name, struct map_info *map);
 270 void map_destroy(struct mtd_info *mtd);
 271
 272 #define ENABLE_VPP(map) do { if (map->set_vpp) map->set_vpp(map, 1); } while (0)
 273 #define DISABLE_VPP(map) do { if (map->set_vpp) map->set_vpp(map, 0); } while (0)
 274
 275 #define INVALIDATE_CACHED_RANGE(map, from, size) \
 276         do { if (map->inval_cache) map->inval_cache(map, from, size); } while (0)
 277
 278
 279 static inline int map_word_equal(struct map_info *map, map_word val1, map_word val2)
 280 {
 281         int i;
 282
 283         for (i = 0; i < map_words(map); i++) {
 284                 if (val1.x[i] != val2.x[i])
 285                         return 0;
 286         }
 287
 288         return 1;
 289 }
 290
 291 static inline map_word map_word_and(struct map_info *map, map_word val1, map_word val2)
 292 {
 293         map_word r;
 294         int i;
 295
 296         for (i = 0; i < map_words(map); i++)
 297                 r.x[i] = val1.x[i] & val2.x[i];
 298
 299         return r;
 300 }
 301
 302 static inline map_word map_word_clr(struct map_info *map, map_word val1, map_word val2)
 303 {
 304         map_word r;
 305         int i;
 306
 307         for (i = 0; i < map_words(map); i++)
 308                 r.x[i] = val1.x[i] & ~val2.x[i];
 309
 310         return r;
 311 }
 312
 313 static inline map_word map_word_or(struct map_info *map, map_word val1, map_word val2)
 314 {
 315         map_word r;
 316         int i;
 317
 318         for (i = 0; i < map_words(map); i++)
 319                 r.x[i] = val1.x[i] | val2.x[i];
 320
 321         return r;
 322 }
 323
 324 static inline int map_word_andequal(struct map_info *map, map_word val1, map_word val2, map_word val3)
 325 {
 326         int i;
 327
 328         for (i = 0; i < map_words(map); i++) {
 329                 if ((val1.x[i] & val2.x[i]) != val3.x[i])
 330                         return 0;
 331         }
 332
 333         return 1;
 334 }
 335
 336 static inline int map_word_bitsset(struct map_info *map, map_word val1, map_word val2)
 337 {
 338         int i;
 339
 340         for (i = 0; i < map_words(map); i++) {
 341                 if (val1.x[i] & val2.x[i])
 342                         return 1;
 343         }
 344
 345         return 0;
 346 }
 347
 348 static inline map_word map_word_load(struct map_info *map, const void *ptr)
 349 {
 350         map_word r;
 351
 352         if (map_bankwidth_is_1(map))
 353                 r.x[0] = *(unsigned char *)ptr;
 354         else if (map_bankwidth_is_2(map))
 355                 r.x[0] = get_unaligned((uint16_t *)ptr);
 356         else if (map_bankwidth_is_4(map))
 357                 r.x[0] = get_unaligned((uint32_t *)ptr);
 358 #if BITS_PER_LONG >= 64
 359         else if (map_bankwidth_is_8(map))
 360                 r.x[0] = get_unaligned((uint64_t *)ptr);
 361 #endif
 362         else if (map_bankwidth_is_large(map))
 363                 memcpy(r.x, ptr, map->bankwidth);
 364         else
 365                 BUG();
 366
 367         return r;
 368 }
 369
 370 static inline map_word map_word_load_partial(struct map_info *map, map_word orig, const unsigned char *buf, int start, int len)
 371 {
 372         int i;
 373
 374         if (map_bankwidth_is_large(map)) {
 375                 char *dest = (char *)&orig;
 376
 377                 memcpy(dest+start, buf, len);
 378         } else {
 379                 for (i = start; i < start+len; i++) {
 380                         int bitpos;
 381
 382 #ifdef __LITTLE_ENDIAN
 383                         bitpos = i * 8;
 384 #else /* __BIG_ENDIAN */
 385                         bitpos = (map_bankwidth(map) - 1 - i) * 8;
 386 #endif
 387                         orig.x[0] &= ~(0xff << bitpos);
 388                         orig.x[0] |= (unsigned long)buf[i-start] << bitpos;
 389                 }
 390         }
 391         return orig;
 392 }
 393
 394 #if BITS_PER_LONG < 64
 395 #define MAP_FF_LIMIT 4
 396 #else
 397 #define MAP_FF_LIMIT 8
 398 #endif
 399
 400 static inline map_word map_word_ff(struct map_info *map)
 401 {
 402         map_word r;
 403         int i;
 404
 405         if (map_bankwidth(map) < MAP_FF_LIMIT) {
 406                 int bw = 8 * map_bankwidth(map);
 407
 408                 r.x[0] = (1UL << bw) - 1;
 409         } else {
 410                 for (i = 0; i < map_words(map); i++)
 411                         r.x[i] = ~0UL;
 412         }
 413         return r;
 414 }
 415
 416 static inline map_word inline_map_read(struct map_info *map, unsigned long ofs)
 417 {
 418         map_word r;
 419
 420         if (map_bankwidth_is_1(map))
 421                 r.x[0] = __raw_readb(map->virt + ofs);
 422         else if (map_bankwidth_is_2(map))
 423                 r.x[0] = __raw_readw(map->virt + ofs);
 424         else if (map_bankwidth_is_4(map))
 425                 r.x[0] = __raw_readl(map->virt + ofs);
 426 #if BITS_PER_LONG >= 64
 427         else if (map_bankwidth_is_8(map))
 428                 r.x[0] = __raw_readq(map->virt + ofs);
 429 #endif
 430         else if (map_bankwidth_is_large(map))
 431                 memcpy_fromio(r.x, map->virt + ofs, map->bankwidth);
 432         else
 433                 BUG();
 434
 435         return r;
 436 }
 437
 438 static inline void inline_map_write(struct map_info *map, const map_word datum, unsigned long ofs)
 439 {
 440         if (map_bankwidth_is_1(map))
 441                 __raw_writeb(datum.x[0], map->virt + ofs);
 442         else if (map_bankwidth_is_2(map))
 443                 __raw_writew(datum.x[0], map->virt + ofs);
 444         else if (map_bankwidth_is_4(map))
 445                 __raw_writel(datum.x[0], map->virt + ofs);
 446 #if BITS_PER_LONG >= 64
 447         else if (map_bankwidth_is_8(map))
 448                 __raw_writeq(datum.x[0], map->virt + ofs);
 449 #endif
 450         else if (map_bankwidth_is_large(map))
 451                 memcpy_toio(map->virt+ofs, datum.x, map->bankwidth);
 452         else
 453                 BUG();
 454         mb();
 455 }
 456
 457 static inline void inline_map_copy_from(struct map_info *map, void *to, unsigned long from, ssize_t len)
 458 {
 459         if (map->cached)
 460                 memcpy(to, (char *)map->cached + from, len);
 461         else
 462                 memcpy_fromio(to, map->virt + from, len);
 463 }
 464
 465 static inline void inline_map_copy_to(struct map_info *map, unsigned long to, const void *from, ssize_t len)
 466 {
 467         memcpy_toio(map->virt + to, from, len);
 468 }
 469
 470 #ifdef CONFIG_MTD_COMPLEX_MAPPINGS
 471 #define map_read(map, ofs) (map)->read(map, ofs)
 472 #define map_copy_from(map, to, from, len) (map)->copy_from(map, to, from, len)
 473 #define map_write(map, datum, ofs) (map)->write(map, datum, ofs)
 474 #define map_copy_to(map, to, from, len) (map)->copy_to(map, to, from, len)
 475
 476 extern void simple_map_init(struct map_info *);
 477 #define map_is_linear(map) (map->phys != NO_XIP)
 478
 479 #else
 480 #define map_read(map, ofs) inline_map_read(map, ofs)
 481 #define map_copy_from(map, to, from, len) inline_map_copy_from(map, to, from, len)
 482 #define map_write(map, datum, ofs) inline_map_write(map, datum, ofs)
 483 #define map_copy_to(map, to, from, len) inline_map_copy_to(map, to, from, len)
 484
 485
 486 #define simple_map_init(map) BUG_ON(!map_bankwidth_supported((map)->bankwidth))
 487 #define map_is_linear(map) ({ (void)(map); 1; })
 488
 489 #endif /* !CONFIG_MTD_COMPLEX_MAPPINGS */
 490
 491 #endif /* __LINUX_MTD_MAP_H__ */