drivers/mtd/lpddr/lpddr_cmds.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * LPDDR flash memory device operations. This module provides read, write,
   4  * erase, lock/unlock support for LPDDR flash memories
   5  * (C) 2008 Korolev Alexey <[email protected]>
   6  * (C) 2008 Vasiliy Leonenko <[email protected]>
   7  * Many thanks to Roman Borisov for initial enabling
   8  *
   9  * TODO:
  10  * Implement VPP management
  11  * Implement XIP support
  12  * Implement OTP support
  13  */
  14 #include <linux/mtd/pfow.h>
  15 #include <linux/mtd/qinfo.h>
  16 #include <linux/slab.h>
  17 #include <linux/module.h>
  18
  19 static int lpddr_read(struct mtd_info *mtd, loff_t adr, size_t len,
  20                                         size_t *retlen, u_char *buf);
  21 static int lpddr_write_buffers(struct mtd_info *mtd, loff_t to,
  22                                 size_t len, size_t *retlen, const u_char *buf);
  23 static int lpddr_writev(struct mtd_info *mtd, const struct kvec *vecs,
  24                                 unsigned long count, loff_t to, size_t *retlen);
  25 static int lpddr_erase(struct mtd_info *mtd, struct erase_info *instr);
  26 static int lpddr_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
  27 static int lpddr_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
  28 static int lpddr_point(struct mtd_info *mtd, loff_t adr, size_t len,
  29                         size_t *retlen, void **mtdbuf, resource_size_t *phys);
  30 static int lpddr_unpoint(struct mtd_info *mtd, loff_t adr, size_t len);
  31 static int get_chip(struct map_info *map, struct flchip *chip, int mode);
  32 static int chip_ready(struct map_info *map, struct flchip *chip, int mode);
  33 static void put_chip(struct map_info *map, struct flchip *chip);
  34
  35 struct mtd_info *lpddr_cmdset(struct map_info *map)
  36 {
  37         struct lpddr_private *lpddr = map->fldrv_priv;
  38         struct flchip_shared *shared;
  39         struct flchip *chip;
  40         struct mtd_info *mtd;
  41         int numchips;
  42         int i, j;
  43
  44         mtd = kzalloc(sizeof(*mtd), GFP_KERNEL);
  45         if (!mtd)
  46                 return NULL;
  47         mtd->priv = map;
  48         mtd->type = MTD_NORFLASH;
  49
  50         /* Fill in the default mtd operations */
  51         mtd->_read = lpddr_read;
  52         mtd->type = MTD_NORFLASH;
  53         mtd->flags = MTD_CAP_NORFLASH;
  54         mtd->flags &= ~MTD_BIT_WRITEABLE;
  55         mtd->_erase = lpddr_erase;
  56         mtd->_write = lpddr_write_buffers;
  57         mtd->_writev = lpddr_writev;
  58         mtd->_lock = lpddr_lock;
  59         mtd->_unlock = lpddr_unlock;
  60         if (map_is_linear(map)) {
  61                 mtd->_point = lpddr_point;
  62                 mtd->_unpoint = lpddr_unpoint;
  63         }
  64         mtd->size = 1 << lpddr->qinfo->DevSizeShift;
  65         mtd->erasesize = 1 << lpddr->qinfo->UniformBlockSizeShift;
  66         mtd->writesize = 1 << lpddr->qinfo->BufSizeShift;
  67
  68         shared = kmalloc_array(lpddr->numchips, sizeof(struct flchip_shared),
  69                                                 GFP_KERNEL);
  70         if (!shared) {
  71                 kfree(mtd);
  72                 return NULL;
  73         }
  74
  75         chip = &lpddr->chips[0];
  76         numchips = lpddr->numchips / lpddr->qinfo->HWPartsNum;
  77         for (i = 0; i < numchips; i++) {
  78                 shared[i].writing = shared[i].erasing = NULL;
  79                 mutex_init(&shared[i].lock);
  80                 for (j = 0; j < lpddr->qinfo->HWPartsNum; j++) {
  81                         *chip = lpddr->chips[i];
  82                         chip->start += j << lpddr->chipshift;
  83                         chip->oldstate = chip->state = FL_READY;
  84                         chip->priv = &shared[i];
  85                         /* those should be reset too since
  86                            they create memory references. */
  87                         init_waitqueue_head(&chip->wq);
  88                         mutex_init(&chip->mutex);
  89                         chip++;
  90                 }
  91         }
  92
  93         return mtd;
  94 }
  95 EXPORT_SYMBOL(lpddr_cmdset);
  96
  97 static int wait_for_ready(struct map_info *map, struct flchip *chip,
  98                 unsigned int chip_op_time)
  99 {
 100         unsigned int timeo, reset_timeo, sleep_time;
 101         unsigned int dsr;
 102         flstate_t chip_state = chip->state;
 103         int ret = 0;
 104
 105         /* set our timeout to 8 times the expected delay */
 106         timeo = chip_op_time * 8;
 107         if (!timeo)
 108                 timeo = 500000;
 109         reset_timeo = timeo;
 110         sleep_time = chip_op_time / 2;
 111
 112         for (;;) {
 113                 dsr = CMDVAL(map_read(map, map->pfow_base + PFOW_DSR));
 114                 if (dsr & DSR_READY_STATUS)
 115                         break;
 116                 if (!timeo) {
 117                         printk(KERN_ERR "%s: Flash timeout error state %d \n",
 118                                                         map->name, chip_state);
 119                         ret = -ETIME;
 120                         break;
 121                 }
 122
 123                 /* OK Still waiting. Drop the lock, wait a while and retry. */
 124                 mutex_unlock(&chip->mutex);
 125                 if (sleep_time >= 1000000/HZ) {
 126                         /*
 127                          * Half of the normal delay still remaining
 128                          * can be performed with a sleeping delay instead
 129                          * of busy waiting.
 130                          */
 131                         msleep(sleep_time/1000);
 132                         timeo -= sleep_time;
 133                         sleep_time = 1000000/HZ;
 134                 } else {
 135                         udelay(1);
 136                         cond_resched();
 137                         timeo--;
 138                 }
 139                 mutex_lock(&chip->mutex);
 140
 141                 while (chip->state != chip_state) {
 142                         /* Someone's suspended the operation: sleep */
 143                         DECLARE_WAITQUEUE(wait, current);
 144                         set_current_state(TASK_UNINTERRUPTIBLE);
 145                         add_wait_queue(&chip->wq, &wait);
 146                         mutex_unlock(&chip->mutex);
 147                         schedule();
 148                         remove_wait_queue(&chip->wq, &wait);
 149                         mutex_lock(&chip->mutex);
 150                 }
 151                 if (chip->erase_suspended || chip->write_suspended)  {
 152                         /* Suspend has occurred while sleep: reset timeout */
 153                         timeo = reset_timeo;
 154                         chip->erase_suspended = chip->write_suspended = 0;
 155                 }
 156         }
 157         /* check status for errors */
 158         if (dsr & DSR_ERR) {
 159                 /* Clear DSR*/
 160                 map_write(map, CMD(~(DSR_ERR)), map->pfow_base + PFOW_DSR);
 161                 printk(KERN_WARNING"%s: Bad status on wait: 0x%x \n",
 162                                 map->name, dsr);
 163                 print_drs_error(dsr);
 164                 ret = -EIO;
 165         }
 166         chip->state = FL_READY;
 167         return ret;
 168 }
 169
 170 static int get_chip(struct map_info *map, struct flchip *chip, int mode)
 171 {
 172         int ret;
 173         DECLARE_WAITQUEUE(wait, current);
 174
 175  retry:
 176         if (chip->priv && (mode == FL_WRITING || mode == FL_ERASING)
 177                 && chip->state != FL_SYNCING) {
 178                 /*
 179                  * OK. We have possibility for contension on the write/erase
 180                  * operations which are global to the real chip and not per
 181                  * partition.  So let's fight it over in the partition which
 182                  * currently has authority on the operation.
 183                  *
 184                  * The rules are as follows:
 185                  *
 186                  * - any write operation must own shared->writing.
 187                  *
 188                  * - any erase operation must own _both_ shared->writing and
 189                  *   shared->erasing.
 190                  *
 191                  * - contension arbitration is handled in the owner's context.
 192                  *
 193                  * The 'shared' struct can be read and/or written only when
 194                  * its lock is taken.
 195                  */
 196                 struct flchip_shared *shared = chip->priv;
 197                 struct flchip *contender;
 198                 mutex_lock(&shared->lock);
 199                 contender = shared->writing;
 200                 if (contender && contender != chip) {
 201                         /*
 202                          * The engine to perform desired operation on this
 203                          * partition is already in use by someone else.
 204                          * Let's fight over it in the context of the chip
 205                          * currently using it.  If it is possible to suspend,
 206                          * that other partition will do just that, otherwise
 207                          * it'll happily send us to sleep.  In any case, when
 208                          * get_chip returns success we're clear to go ahead.
 209                          */
 210                         ret = mutex_trylock(&contender->mutex);
 211                         mutex_unlock(&shared->lock);
 212                         if (!ret)
 213                                 goto retry;
 214                         mutex_unlock(&chip->mutex);
 215                         ret = chip_ready(map, contender, mode);
 216                         mutex_lock(&chip->mutex);
 217
 218                         if (ret == -EAGAIN) {
 219                                 mutex_unlock(&contender->mutex);
 220                                 goto retry;
 221                         }
 222                         if (ret) {
 223                                 mutex_unlock(&contender->mutex);
 224                                 return ret;
 225                         }
 226                         mutex_lock(&shared->lock);
 227
 228                         /* We should not own chip if it is already in FL_SYNCING
 229                          * state. Put contender and retry. */
 230                         if (chip->state == FL_SYNCING) {
 231                                 put_chip(map, contender);
 232                                 mutex_unlock(&contender->mutex);
 233                                 goto retry;
 234                         }
 235                         mutex_unlock(&contender->mutex);
 236                 }
 237
 238                 /* Check if we have suspended erase on this chip.
 239                    Must sleep in such a case. */
 240                 if (mode == FL_ERASING && shared->erasing
 241                     && shared->erasing->oldstate == FL_ERASING) {
 242                         mutex_unlock(&shared->lock);
 243                         set_current_state(TASK_UNINTERRUPTIBLE);
 244                         add_wait_queue(&chip->wq, &wait);
 245                         mutex_unlock(&chip->mutex);
 246                         schedule();
 247                         remove_wait_queue(&chip->wq, &wait);
 248                         mutex_lock(&chip->mutex);
 249                         goto retry;
 250                 }
 251
 252                 /* We now own it */
 253                 shared->writing = chip;
 254                 if (mode == FL_ERASING)
 255                         shared->erasing = chip;
 256                 mutex_unlock(&shared->lock);
 257         }
 258
 259         ret = chip_ready(map, chip, mode);
 260         if (ret == -EAGAIN)
 261                 goto retry;
 262
 263         return ret;
 264 }
 265
 266 static int chip_ready(struct map_info *map, struct flchip *chip, int mode)
 267 {
 268         struct lpddr_private *lpddr = map->fldrv_priv;
 269         int ret = 0;
 270         DECLARE_WAITQUEUE(wait, current);
 271
 272         /* Prevent setting state FL_SYNCING for chip in suspended state. */
 273         if (FL_SYNCING == mode && FL_READY != chip->oldstate)
 274                 goto sleep;
 275
 276         switch (chip->state) {
 277         case FL_READY:
 278         case FL_JEDEC_QUERY:
 279                 return 0;
 280
 281         case FL_ERASING:
 282                 if (!lpddr->qinfo->SuspEraseSupp ||
 283                         !(mode == FL_READY || mode == FL_POINT))
 284                         goto sleep;
 285
 286                 map_write(map, CMD(LPDDR_SUSPEND),
 287                         map->pfow_base + PFOW_PROGRAM_ERASE_SUSPEND);
 288                 chip->oldstate = FL_ERASING;
 289                 chip->state = FL_ERASE_SUSPENDING;
 290                 ret = wait_for_ready(map, chip, 0);
 291                 if (ret) {
 292                         /* Oops. something got wrong. */
 293                         /* Resume and pretend we weren't here.  */
 294                         put_chip(map, chip);
 295                         printk(KERN_ERR "%s: suspend operation failed."
 296                                         "State may be wrong \n", map->name);
 297                         return -EIO;
 298                 }
 299                 chip->erase_suspended = 1;
 300                 chip->state = FL_READY;
 301                 return 0;
 302                 /* Erase suspend */
 303         case FL_POINT:
 304                 /* Only if there's no operation suspended... */
 305                 if (mode == FL_READY && chip->oldstate == FL_READY)
 306                         return 0;
 307                 fallthrough;
 308         default:
 309 sleep:
 310                 set_current_state(TASK_UNINTERRUPTIBLE);
 311                 add_wait_queue(&chip->wq, &wait);
 312                 mutex_unlock(&chip->mutex);
 313                 schedule();
 314                 remove_wait_queue(&chip->wq, &wait);
 315                 mutex_lock(&chip->mutex);
 316                 return -EAGAIN;
 317         }
 318 }
 319
 320 static void put_chip(struct map_info *map, struct flchip *chip)
 321 {
 322         if (chip->priv) {
 323                 struct flchip_shared *shared = chip->priv;
 324                 mutex_lock(&shared->lock);
 325                 if (shared->writing == chip && chip->oldstate == FL_READY) {
 326                         /* We own the ability to write, but we're done */
 327                         shared->writing = shared->erasing;
 328                         if (shared->writing && shared->writing != chip) {
 329                                 /* give back the ownership */
 330                                 struct flchip *loaner = shared->writing;
 331                                 mutex_lock(&loaner->mutex);
 332                                 mutex_unlock(&shared->lock);
 333                                 mutex_unlock(&chip->mutex);
 334                                 put_chip(map, loaner);
 335                                 mutex_lock(&chip->mutex);
 336                                 mutex_unlock(&loaner->mutex);
 337                                 wake_up(&chip->wq);
 338                                 return;
 339                         }
 340                         shared->erasing = NULL;
 341                         shared->writing = NULL;
 342                 } else if (shared->erasing == chip && shared->writing != chip) {
 343                         /*
 344                          * We own the ability to erase without the ability
 345                          * to write, which means the erase was suspended
 346                          * and some other partition is currently writing.
 347                          * Don't let the switch below mess things up since
 348                          * we don't have ownership to resume anything.
 349                          */
 350                         mutex_unlock(&shared->lock);
 351                         wake_up(&chip->wq);
 352                         return;
 353                 }
 354                 mutex_unlock(&shared->lock);
 355         }
 356
 357         switch (chip->oldstate) {
 358         case FL_ERASING:
 359                 map_write(map, CMD(LPDDR_RESUME),
 360                                 map->pfow_base + PFOW_COMMAND_CODE);
 361                 map_write(map, CMD(LPDDR_START_EXECUTION),
 362                                 map->pfow_base + PFOW_COMMAND_EXECUTE);
 363                 chip->oldstate = FL_READY;
 364                 chip->state = FL_ERASING;
 365                 break;
 366         case FL_READY:
 367                 break;
 368         default:
 369                 printk(KERN_ERR "%s: put_chip() called with oldstate %d!\n",
 370                                 map->name, chip->oldstate);
 371         }
 372         wake_up(&chip->wq);
 373 }
 374
 375 static int do_write_buffer(struct map_info *map, struct flchip *chip,
 376                         unsigned long adr, const struct kvec **pvec,
 377                         unsigned long *pvec_seek, int len)
 378 {
 379         struct lpddr_private *lpddr = map->fldrv_priv;
 380         map_word datum;
 381         int ret, wbufsize, word_gap, words;
 382         const struct kvec *vec;
 383         unsigned long vec_seek;
 384         unsigned long prog_buf_ofs;
 385
 386         wbufsize = 1 << lpddr->qinfo->BufSizeShift;
 387
 388         mutex_lock(&chip->mutex);
 389         ret = get_chip(map, chip, FL_WRITING);
 390         if (ret) {
 391                 mutex_unlock(&chip->mutex);
 392                 return ret;
 393         }
 394         /* Figure out the number of words to write */
 395         word_gap = (-adr & (map_bankwidth(map)-1));
 396         words = (len - word_gap + map_bankwidth(map) - 1) / map_bankwidth(map);
 397         if (!word_gap) {
 398                 words--;
 399         } else {
 400                 word_gap = map_bankwidth(map) - word_gap;
 401                 adr -= word_gap;
 402                 datum = map_word_ff(map);
 403         }
 404         /* Write data */
 405         /* Get the program buffer offset from PFOW register data first*/
 406         prog_buf_ofs = map->pfow_base + CMDVAL(map_read(map,
 407                                 map->pfow_base + PFOW_PROGRAM_BUFFER_OFFSET));
 408         vec = *pvec;
 409         vec_seek = *pvec_seek;
 410         do {
 411                 int n = map_bankwidth(map) - word_gap;
 412
 413                 if (n > vec->iov_len - vec_seek)
 414                         n = vec->iov_len - vec_seek;
 415                 if (n > len)
 416                         n = len;
 417
 418                 if (!word_gap && (len < map_bankwidth(map)))
 419                         datum = map_word_ff(map);
 420
 421                 datum = map_word_load_partial(map, datum,
 422                                 vec->iov_base + vec_seek, word_gap, n);
 423
 424                 len -= n;
 425                 word_gap += n;
 426                 if (!len || word_gap == map_bankwidth(map)) {
 427                         map_write(map, datum, prog_buf_ofs);
 428                         prog_buf_ofs += map_bankwidth(map);
 429                         word_gap = 0;
 430                 }
 431
 432                 vec_seek += n;
 433                 if (vec_seek == vec->iov_len) {
 434                         vec++;
 435                         vec_seek = 0;
 436                 }
 437         } while (len);
 438         *pvec = vec;
 439         *pvec_seek = vec_seek;
 440
 441         /* GO GO GO */
 442         send_pfow_command(map, LPDDR_BUFF_PROGRAM, adr, wbufsize, NULL);
 443         chip->state = FL_WRITING;
 444         ret = wait_for_ready(map, chip, (1<<lpddr->qinfo->ProgBufferTime));
 445         if (ret)        {
 446                 printk(KERN_WARNING"%s Buffer program error: %d at %lx; \n",
 447                         map->name, ret, adr);
 448                 goto out;
 449         }
 450
 451  out:   put_chip(map, chip);
 452         mutex_unlock(&chip->mutex);
 453         return ret;
 454 }
 455
 456 static int do_erase_oneblock(struct mtd_info *mtd, loff_t adr)
 457 {
 458         struct map_info *map = mtd->priv;
 459         struct lpddr_private *lpddr = map->fldrv_priv;
 460         int chipnum = adr >> lpddr->chipshift;
 461         struct flchip *chip = &lpddr->chips[chipnum];
 462         int ret;
 463
 464         mutex_lock(&chip->mutex);
 465         ret = get_chip(map, chip, FL_ERASING);
 466         if (ret) {
 467                 mutex_unlock(&chip->mutex);
 468                 return ret;
 469         }
 470         send_pfow_command(map, LPDDR_BLOCK_ERASE, adr, 0, NULL);
 471         chip->state = FL_ERASING;
 472         ret = wait_for_ready(map, chip, (1<<lpddr->qinfo->BlockEraseTime)*1000);
 473         if (ret) {
 474                 printk(KERN_WARNING"%s Erase block error %d at : %llx\n",
 475                         map->name, ret, adr);
 476                 goto out;
 477         }
 478  out:   put_chip(map, chip);
 479         mutex_unlock(&chip->mutex);
 480         return ret;
 481 }
 482
 483 static int lpddr_read(struct mtd_info *mtd, loff_t adr, size_t len,
 484                         size_t *retlen, u_char *buf)
 485 {
 486         struct map_info *map = mtd->priv;
 487         struct lpddr_private *lpddr = map->fldrv_priv;
 488         int chipnum = adr >> lpddr->chipshift;
 489         struct flchip *chip = &lpddr->chips[chipnum];
 490         int ret = 0;
 491
 492         mutex_lock(&chip->mutex);
 493         ret = get_chip(map, chip, FL_READY);
 494         if (ret) {
 495                 mutex_unlock(&chip->mutex);
 496                 return ret;
 497         }
 498
 499         map_copy_from(map, buf, adr, len);
 500         *retlen = len;
 501
 502         put_chip(map, chip);
 503         mutex_unlock(&chip->mutex);
 504         return ret;
 505 }
 506
 507 static int lpddr_point(struct mtd_info *mtd, loff_t adr, size_t len,
 508                         size_t *retlen, void **mtdbuf, resource_size_t *phys)
 509 {
 510         struct map_info *map = mtd->priv;
 511         struct lpddr_private *lpddr = map->fldrv_priv;
 512         int chipnum = adr >> lpddr->chipshift;
 513         unsigned long ofs, last_end = 0;
 514         struct flchip *chip = &lpddr->chips[chipnum];
 515         int ret = 0;
 516
 517         if (!map->virt)
 518                 return -EINVAL;
 519
 520         /* ofs: offset within the first chip that the first read should start */
 521         ofs = adr - (chipnum << lpddr->chipshift);
 522         *mtdbuf = (void *)map->virt + chip->start + ofs;
 523
 524         while (len) {
 525                 unsigned long thislen;
 526
 527                 if (chipnum >= lpddr->numchips)
 528                         break;
 529
 530                 /* We cannot point across chips that are virtually disjoint */
 531                 if (!last_end)
 532                         last_end = chip->start;
 533                 else if (chip->start != last_end)
 534                         break;
 535
 536                 if ((len + ofs - 1) >> lpddr->chipshift)
 537                         thislen = (1<<lpddr->chipshift) - ofs;
 538                 else
 539                         thislen = len;
 540                 /* get the chip */
 541                 mutex_lock(&chip->mutex);
 542                 ret = get_chip(map, chip, FL_POINT);
 543                 mutex_unlock(&chip->mutex);
 544                 if (ret)
 545                         break;
 546
 547                 chip->state = FL_POINT;
 548                 chip->ref_point_counter++;
 549                 *retlen += thislen;
 550                 len -= thislen;
 551
 552                 ofs = 0;
 553                 last_end += 1 << lpddr->chipshift;
 554                 chipnum++;
 555                 chip = &lpddr->chips[chipnum];
 556         }
 557         return 0;
 558 }
 559
 560 static int lpddr_unpoint (struct mtd_info *mtd, loff_t adr, size_t len)
 561 {
 562         struct map_info *map = mtd->priv;
 563         struct lpddr_private *lpddr = map->fldrv_priv;
 564         int chipnum = adr >> lpddr->chipshift, err = 0;
 565         unsigned long ofs;
 566
 567         /* ofs: offset within the first chip that the first read should start */
 568         ofs = adr - (chipnum << lpddr->chipshift);
 569
 570         while (len) {
 571                 unsigned long thislen;
 572                 struct flchip *chip;
 573
 574                 chip = &lpddr->chips[chipnum];
 575                 if (chipnum >= lpddr->numchips)
 576                         break;
 577
 578                 if ((len + ofs - 1) >> lpddr->chipshift)
 579                         thislen = (1<<lpddr->chipshift) - ofs;
 580                 else
 581                         thislen = len;
 582
 583                 mutex_lock(&chip->mutex);
 584                 if (chip->state == FL_POINT) {
 585                         chip->ref_point_counter--;
 586                         if (chip->ref_point_counter == 0)
 587                                 chip->state = FL_READY;
 588                 } else {
 589                         printk(KERN_WARNING "%s: Warning: unpoint called on non"
 590                                         "pointed region\n", map->name);
 591                         err = -EINVAL;
 592                 }
 593
 594                 put_chip(map, chip);
 595                 mutex_unlock(&chip->mutex);
 596
 597                 len -= thislen;
 598                 ofs = 0;
 599                 chipnum++;
 600         }
 601
 602         return err;
 603 }
 604
 605 static int lpddr_write_buffers(struct mtd_info *mtd, loff_t to, size_t len,
 606                                 size_t *retlen, const u_char *buf)
 607 {
 608         struct kvec vec;
 609
 610         vec.iov_base = (void *) buf;
 611         vec.iov_len = len;
 612
 613         return lpddr_writev(mtd, &vec, 1, to, retlen);
 614 }
 615
 616
 617 static int lpddr_writev(struct mtd_info *mtd, const struct kvec *vecs,
 618                                 unsigned long count, loff_t to, size_t *retlen)
 619 {
 620         struct map_info *map = mtd->priv;
 621         struct lpddr_private *lpddr = map->fldrv_priv;
 622         int ret = 0;
 623         int chipnum;
 624         unsigned long ofs, vec_seek, i;
 625         int wbufsize = 1 << lpddr->qinfo->BufSizeShift;
 626         size_t len = 0;
 627
 628         for (i = 0; i < count; i++)
 629                 len += vecs[i].iov_len;
 630
 631         if (!len)
 632                 return 0;
 633
 634         chipnum = to >> lpddr->chipshift;
 635
 636         ofs = to;
 637         vec_seek = 0;
 638
 639         do {
 640                 /* We must not cross write block boundaries */
 641                 int size = wbufsize - (ofs & (wbufsize-1));
 642
 643                 if (size > len)
 644                         size = len;
 645
 646                 ret = do_write_buffer(map, &lpddr->chips[chipnum],
 647                                           ofs, &vecs, &vec_seek, size);
 648                 if (ret)
 649                         return ret;
 650
 651                 ofs += size;
 652                 (*retlen) += size;
 653                 len -= size;
 654
 655                 /* Be nice and reschedule with the chip in a usable
 656                  * state for other processes */
 657                 cond_resched();
 658
 659         } while (len);
 660
 661         return 0;
 662 }
 663
 664 static int lpddr_erase(struct mtd_info *mtd, struct erase_info *instr)
 665 {
 666         unsigned long ofs, len;
 667         int ret;
 668         struct map_info *map = mtd->priv;
 669         struct lpddr_private *lpddr = map->fldrv_priv;
 670         int size = 1 << lpddr->qinfo->UniformBlockSizeShift;
 671
 672         ofs = instr->addr;
 673         len = instr->len;
 674
 675         while (len > 0) {
 676                 ret = do_erase_oneblock(mtd, ofs);
 677                 if (ret)
 678                         return ret;
 679                 ofs += size;
 680                 len -= size;
 681         }
 682
 683         return 0;
 684 }
 685
 686 #define DO_XXLOCK_LOCK          1
 687 #define DO_XXLOCK_UNLOCK        2
 688 static int do_xxlock(struct mtd_info *mtd, loff_t adr, uint32_t len, int thunk)
 689 {
 690         int ret = 0;
 691         struct map_info *map = mtd->priv;
 692         struct lpddr_private *lpddr = map->fldrv_priv;
 693         int chipnum = adr >> lpddr->chipshift;
 694         struct flchip *chip = &lpddr->chips[chipnum];
 695
 696         mutex_lock(&chip->mutex);
 697         ret = get_chip(map, chip, FL_LOCKING);
 698         if (ret) {
 699                 mutex_unlock(&chip->mutex);
 700                 return ret;
 701         }
 702
 703         if (thunk == DO_XXLOCK_LOCK) {
 704                 send_pfow_command(map, LPDDR_LOCK_BLOCK, adr, adr + len, NULL);
 705                 chip->state = FL_LOCKING;
 706         } else if (thunk == DO_XXLOCK_UNLOCK) {
 707                 send_pfow_command(map, LPDDR_UNLOCK_BLOCK, adr, adr + len, NULL);
 708                 chip->state = FL_UNLOCKING;
 709         } else
 710                 BUG();
 711
 712         ret = wait_for_ready(map, chip, 1);
 713         if (ret)        {
 714                 printk(KERN_ERR "%s: block unlock error status %d \n",
 715                                 map->name, ret);
 716                 goto out;
 717         }
 718 out:    put_chip(map, chip);
 719         mutex_unlock(&chip->mutex);
 720         return ret;
 721 }
 722
 723 static int lpddr_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
 724 {
 725         return do_xxlock(mtd, ofs, len, DO_XXLOCK_LOCK);
 726 }
 727
 728 static int lpddr_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
 729 {
 730         return do_xxlock(mtd, ofs, len, DO_XXLOCK_UNLOCK);
 731 }
 732
 733 MODULE_LICENSE("GPL");
 734 MODULE_AUTHOR("Alexey Korolev <[email protected]>");
 735 MODULE_DESCRIPTION("MTD driver for LPDDR flash chips");