drivers/mtd/chips/cfi_util.c

   1 /*
   2  * Common Flash Interface support:
   3  *   Generic utility functions not dependent on command set
   4  *
   5  * Copyright (C) 2002 Red Hat
   6  * Copyright (C) 2003 STMicroelectronics Limited
   7  *
   8  * This code is covered by the GPL.
   9  */
  10
  11 #include <linux/module.h>
  12 #include <linux/types.h>
  13 #include <linux/kernel.h>
  14 #include <asm/io.h>
  15 #include <asm/byteorder.h>
  16
  17 #include <linux/errno.h>
  18 #include <linux/slab.h>
  19 #include <linux/delay.h>
  20 #include <linux/interrupt.h>
  21 #include <linux/mtd/xip.h>
  22 #include <linux/mtd/mtd.h>
  23 #include <linux/mtd/map.h>
  24 #include <linux/mtd/cfi.h>
  25
  26 void cfi_udelay(int us)
  27 {
  28         if (us >= 1000) {
  29                 msleep(DIV_ROUND_UP(us, 1000));
  30         } else {
  31                 udelay(us);
  32                 cond_resched();
  33         }
  34 }
  35 EXPORT_SYMBOL(cfi_udelay);
  36
  37 /*
  38  * Returns the command address according to the given geometry.
  39  */
  40 uint32_t cfi_build_cmd_addr(uint32_t cmd_ofs,
  41                                 struct map_info *map, struct cfi_private *cfi)
  42 {
  43         unsigned bankwidth = map_bankwidth(map);
  44         unsigned interleave = cfi_interleave(cfi);
  45         unsigned type = cfi->device_type;
  46         uint32_t addr;
  47
  48         addr = (cmd_ofs * type) * interleave;
  49
  50         /* Modify the unlock address if we are in compatibility mode.
  51          * For 16bit devices on 8 bit busses
  52          * and 32bit devices on 16 bit busses
  53          * set the low bit of the alternating bit sequence of the address.
  54          */
  55         if (((type * interleave) > bankwidth) && ((cmd_ofs & 0xff) == 0xaa))
  56                 addr |= (type >> 1)*interleave;
  57
  58         return  addr;
  59 }
  60 EXPORT_SYMBOL(cfi_build_cmd_addr);
  61
  62 /*
  63  * Transforms the CFI command for the given geometry (bus width & interleave).
  64  * It looks too long to be inline, but in the common case it should almost all
  65  * get optimised away.
  66  */
  67 map_word cfi_build_cmd(u_long cmd, struct map_info *map, struct cfi_private *cfi)
  68 {
  69         map_word val = { {0} };
  70         int wordwidth, words_per_bus, chip_mode, chips_per_word;
  71         unsigned long onecmd;
  72         int i;
  73
  74         /* We do it this way to give the compiler a fighting chance
  75            of optimising away all the crap for 'bankwidth' larger than
  76            an unsigned long, in the common case where that support is
  77            disabled */
  78         if (map_bankwidth_is_large(map)) {
  79                 wordwidth = sizeof(unsigned long);
  80                 words_per_bus = (map_bankwidth(map)) / wordwidth; // i.e. normally 1
  81         } else {
  82                 wordwidth = map_bankwidth(map);
  83                 words_per_bus = 1;
  84         }
  85
  86         chip_mode = map_bankwidth(map) / cfi_interleave(cfi);
  87         chips_per_word = wordwidth * cfi_interleave(cfi) / map_bankwidth(map);
  88
  89         /* First, determine what the bit-pattern should be for a single
  90            device, according to chip mode and endianness... */
  91         switch (chip_mode) {
  92         default: BUG();
  93         case 1:
  94                 onecmd = cmd;
  95                 break;
  96         case 2:
  97                 onecmd = cpu_to_cfi16(map, cmd);
  98                 break;
  99         case 4:
 100                 onecmd = cpu_to_cfi32(map, cmd);
 101                 break;
 102         }
 103
 104         /* Now replicate it across the size of an unsigned long, or
 105            just to the bus width as appropriate */
 106         switch (chips_per_word) {
 107         default: BUG();
 108 #if BITS_PER_LONG >= 64
 109         case 8:
 110                 onecmd |= (onecmd << (chip_mode * 32));
 111 #endif
 112                 fallthrough;
 113         case 4:
 114                 onecmd |= (onecmd << (chip_mode * 16));
 115                 fallthrough;
 116         case 2:
 117                 onecmd |= (onecmd << (chip_mode * 8));
 118                 fallthrough;
 119         case 1:
 120                 ;
 121         }
 122
 123         /* And finally, for the multi-word case, replicate it
 124            in all words in the structure */
 125         for (i=0; i < words_per_bus; i++) {
 126                 val.x[i] = onecmd;
 127         }
 128
 129         return val;
 130 }
 131 EXPORT_SYMBOL(cfi_build_cmd);
 132
 133 unsigned long cfi_merge_status(map_word val, struct map_info *map,
 134                                            struct cfi_private *cfi)
 135 {
 136         int wordwidth, words_per_bus, chip_mode, chips_per_word;
 137         unsigned long onestat, res = 0;
 138         int i;
 139
 140         /* We do it this way to give the compiler a fighting chance
 141            of optimising away all the crap for 'bankwidth' larger than
 142            an unsigned long, in the common case where that support is
 143            disabled */
 144         if (map_bankwidth_is_large(map)) {
 145                 wordwidth = sizeof(unsigned long);
 146                 words_per_bus = (map_bankwidth(map)) / wordwidth; // i.e. normally 1
 147         } else {
 148                 wordwidth = map_bankwidth(map);
 149                 words_per_bus = 1;
 150         }
 151
 152         chip_mode = map_bankwidth(map) / cfi_interleave(cfi);
 153         chips_per_word = wordwidth * cfi_interleave(cfi) / map_bankwidth(map);
 154
 155         onestat = val.x[0];
 156         /* Or all status words together */
 157         for (i=1; i < words_per_bus; i++) {
 158                 onestat |= val.x[i];
 159         }
 160
 161         res = onestat;
 162         switch(chips_per_word) {
 163         default: BUG();
 164 #if BITS_PER_LONG >= 64
 165         case 8:
 166                 res |= (onestat >> (chip_mode * 32));
 167 #endif
 168                 fallthrough;
 169         case 4:
 170                 res |= (onestat >> (chip_mode * 16));
 171                 fallthrough;
 172         case 2:
 173                 res |= (onestat >> (chip_mode * 8));
 174                 fallthrough;
 175         case 1:
 176                 ;
 177         }
 178
 179         /* Last, determine what the bit-pattern should be for a single
 180            device, according to chip mode and endianness... */
 181         switch (chip_mode) {
 182         case 1:
 183                 break;
 184         case 2:
 185                 res = cfi16_to_cpu(map, res);
 186                 break;
 187         case 4:
 188                 res = cfi32_to_cpu(map, res);
 189                 break;
 190         default: BUG();
 191         }
 192         return res;
 193 }
 194 EXPORT_SYMBOL(cfi_merge_status);
 195
 196 /*
 197  * Sends a CFI command to a bank of flash for the given geometry.
 198  *
 199  * Returns the offset in flash where the command was written.
 200  * If prev_val is non-null, it will be set to the value at the command address,
 201  * before the command was written.
 202  */
 203 uint32_t cfi_send_gen_cmd(u_char cmd, uint32_t cmd_addr, uint32_t base,
 204                                 struct map_info *map, struct cfi_private *cfi,
 205                                 int type, map_word *prev_val)
 206 {
 207         map_word val;
 208         uint32_t addr = base + cfi_build_cmd_addr(cmd_addr, map, cfi);
 209         val = cfi_build_cmd(cmd, map, cfi);
 210
 211         if (prev_val)
 212                 *prev_val = map_read(map, addr);
 213
 214         map_write(map, val, addr);
 215
 216         return addr - base;
 217 }
 218 EXPORT_SYMBOL(cfi_send_gen_cmd);
 219
 220 int __xipram cfi_qry_present(struct map_info *map, __u32 base,
 221                              struct cfi_private *cfi)
 222 {
 223         int osf = cfi->interleave * cfi->device_type;   /* scale factor */
 224         map_word val[3];
 225         map_word qry[3];
 226
 227         qry[0] = cfi_build_cmd('Q', map, cfi);
 228         qry[1] = cfi_build_cmd('R', map, cfi);
 229         qry[2] = cfi_build_cmd('Y', map, cfi);
 230
 231         val[0] = map_read(map, base + osf*0x10);
 232         val[1] = map_read(map, base + osf*0x11);
 233         val[2] = map_read(map, base + osf*0x12);
 234
 235         if (!map_word_equal(map, qry[0], val[0]))
 236                 return 0;
 237
 238         if (!map_word_equal(map, qry[1], val[1]))
 239                 return 0;
 240
 241         if (!map_word_equal(map, qry[2], val[2]))
 242                 return 0;
 243
 244         return 1;       /* "QRY" found */
 245 }
 246 EXPORT_SYMBOL_GPL(cfi_qry_present);
 247
 248 int __xipram cfi_qry_mode_on(uint32_t base, struct map_info *map,
 249                              struct cfi_private *cfi)
 250 {
 251         cfi_send_gen_cmd(0xF0, 0, base, map, cfi, cfi->device_type, NULL);
 252         cfi_send_gen_cmd(0x98, 0x55, base, map, cfi, cfi->device_type, NULL);
 253         if (cfi_qry_present(map, base, cfi))
 254                 return 1;
 255         /* QRY not found probably we deal with some odd CFI chips */
 256         /* Some revisions of some old Intel chips? */
 257         cfi_send_gen_cmd(0xF0, 0, base, map, cfi, cfi->device_type, NULL);
 258         cfi_send_gen_cmd(0xFF, 0, base, map, cfi, cfi->device_type, NULL);
 259         cfi_send_gen_cmd(0x98, 0x55, base, map, cfi, cfi->device_type, NULL);
 260         if (cfi_qry_present(map, base, cfi))
 261                 return 1;
 262         /* ST M29DW chips */
 263         cfi_send_gen_cmd(0xF0, 0, base, map, cfi, cfi->device_type, NULL);
 264         cfi_send_gen_cmd(0x98, 0x555, base, map, cfi, cfi->device_type, NULL);
 265         if (cfi_qry_present(map, base, cfi))
 266                 return 1;
 267         /* some old SST chips, e.g. 39VF160x/39VF320x */
 268         cfi_send_gen_cmd(0xF0, 0, base, map, cfi, cfi->device_type, NULL);
 269         cfi_send_gen_cmd(0xAA, 0x5555, base, map, cfi, cfi->device_type, NULL);
 270         cfi_send_gen_cmd(0x55, 0x2AAA, base, map, cfi, cfi->device_type, NULL);
 271         cfi_send_gen_cmd(0x98, 0x5555, base, map, cfi, cfi->device_type, NULL);
 272         if (cfi_qry_present(map, base, cfi))
 273                 return 1;
 274         /* SST 39VF640xB */
 275         cfi_send_gen_cmd(0xF0, 0, base, map, cfi, cfi->device_type, NULL);
 276         cfi_send_gen_cmd(0xAA, 0x555, base, map, cfi, cfi->device_type, NULL);
 277         cfi_send_gen_cmd(0x55, 0x2AA, base, map, cfi, cfi->device_type, NULL);
 278         cfi_send_gen_cmd(0x98, 0x555, base, map, cfi, cfi->device_type, NULL);
 279         if (cfi_qry_present(map, base, cfi))
 280                 return 1;
 281         /* QRY not found */
 282         return 0;
 283 }
 284 EXPORT_SYMBOL_GPL(cfi_qry_mode_on);
 285
 286 void __xipram cfi_qry_mode_off(uint32_t base, struct map_info *map,
 287                                struct cfi_private *cfi)
 288 {
 289         cfi_send_gen_cmd(0xF0, 0, base, map, cfi, cfi->device_type, NULL);
 290         cfi_send_gen_cmd(0xFF, 0, base, map, cfi, cfi->device_type, NULL);
 291         /* M29W128G flashes require an additional reset command
 292            when exit qry mode */
 293         if ((cfi->mfr == CFI_MFR_ST) && (cfi->id == 0x227E || cfi->id == 0x7E))
 294                 cfi_send_gen_cmd(0xF0, 0, base, map, cfi, cfi->device_type, NULL);
 295 }
 296 EXPORT_SYMBOL_GPL(cfi_qry_mode_off);
 297
 298 struct cfi_extquery *
 299 __xipram cfi_read_pri(struct map_info *map, __u16 adr, __u16 size, const char* name)
 300 {
 301         struct cfi_private *cfi = map->fldrv_priv;
 302         __u32 base = 0; // cfi->chips[0].start;
 303         int ofs_factor = cfi->interleave * cfi->device_type;
 304         int i;
 305         struct cfi_extquery *extp = NULL;
 306
 307         if (!adr)
 308                 goto out;
 309
 310         printk(KERN_INFO "%s Extended Query Table at 0x%4.4X\n", name, adr);
 311
 312         extp = kmalloc(size, GFP_KERNEL);
 313         if (!extp)
 314                 goto out;
 315
 316 #ifdef CONFIG_MTD_XIP
 317         local_irq_disable();
 318 #endif
 319
 320         /* Switch it into Query Mode */
 321         cfi_qry_mode_on(base, map, cfi);
 322         /* Read in the Extended Query Table */
 323         for (i=0; i<size; i++) {
 324                 ((unsigned char *)extp)[i] =
 325                         cfi_read_query(map, base+((adr+i)*ofs_factor));
 326         }
 327
 328         /* Make sure it returns to read mode */
 329         cfi_qry_mode_off(base, map, cfi);
 330
 331 #ifdef CONFIG_MTD_XIP
 332         (void) map_read(map, base);
 333         xip_iprefetch();
 334         local_irq_enable();
 335 #endif
 336
 337  out:   return extp;
 338 }
 339
 340 EXPORT_SYMBOL(cfi_read_pri);
 341
 342 void cfi_fixup(struct mtd_info *mtd, struct cfi_fixup *fixups)
 343 {
 344         struct map_info *map = mtd->priv;
 345         struct cfi_private *cfi = map->fldrv_priv;
 346         struct cfi_fixup *f;
 347
 348         for (f=fixups; f->fixup; f++) {
 349                 if (((f->mfr == CFI_MFR_ANY) || (f->mfr == cfi->mfr)) &&
 350                     ((f->id  == CFI_ID_ANY)  || (f->id  == cfi->id))) {
 351                         f->fixup(mtd);
 352                 }
 353         }
 354 }
 355
 356 EXPORT_SYMBOL(cfi_fixup);
 357
 358 int cfi_varsize_frob(struct mtd_info *mtd, varsize_frob_t frob,
 359                                      loff_t ofs, size_t len, void *thunk)
 360 {
 361         struct map_info *map = mtd->priv;
 362         struct cfi_private *cfi = map->fldrv_priv;
 363         unsigned long adr;
 364         int chipnum, ret = 0;
 365         int i, first;
 366         struct mtd_erase_region_info *regions = mtd->eraseregions;
 367
 368         /* Check that both start and end of the requested erase are
 369          * aligned with the erasesize at the appropriate addresses.
 370          */
 371
 372         i = 0;
 373
 374         /* Skip all erase regions which are ended before the start of
 375            the requested erase. Actually, to save on the calculations,
 376            we skip to the first erase region which starts after the
 377            start of the requested erase, and then go back one.
 378         */
 379
 380         while (i < mtd->numeraseregions && ofs >= regions[i].offset)
 381                i++;
 382         i--;
 383
 384         /* OK, now i is pointing at the erase region in which this
 385            erase request starts. Check the start of the requested
 386            erase range is aligned with the erase size which is in
 387            effect here.
 388         */
 389
 390         if (ofs & (regions[i].erasesize-1))
 391                 return -EINVAL;
 392
 393         /* Remember the erase region we start on */
 394         first = i;
 395
 396         /* Next, check that the end of the requested erase is aligned
 397          * with the erase region at that address.
 398          */
 399
 400         while (i<mtd->numeraseregions && (ofs + len) >= regions[i].offset)
 401                 i++;
 402
 403         /* As before, drop back one to point at the region in which
 404            the address actually falls
 405         */
 406         i--;
 407
 408         if ((ofs + len) & (regions[i].erasesize-1))
 409                 return -EINVAL;
 410
 411         chipnum = ofs >> cfi->chipshift;
 412         adr = ofs - (chipnum << cfi->chipshift);
 413
 414         i=first;
 415
 416         while(len) {
 417                 int size = regions[i].erasesize;
 418
 419                 ret = (*frob)(map, &cfi->chips[chipnum], adr, size, thunk);
 420
 421                 if (ret)
 422                         return ret;
 423
 424                 adr += size;
 425                 ofs += size;
 426                 len -= size;
 427
 428                 if (ofs == regions[i].offset + size * regions[i].numblocks)
 429                         i++;
 430
 431                 if (adr >> cfi->chipshift) {
 432                         adr = 0;
 433                         chipnum++;
 434
 435                         if (chipnum >= cfi->numchips)
 436                                 break;
 437                 }
 438         }
 439
 440         return 0;
 441 }
 442
 443 EXPORT_SYMBOL(cfi_varsize_frob);
 444
 445 MODULE_LICENSE("GPL");