drivers/mtd/nand/nand_base.c

   1 /*
   2  *  drivers/mtd/nand.c
   3  *
   4  *  Overview:
   5  *   This is the generic MTD driver for NAND flash devices. It should be
   6  *   capable of working with almost all NAND chips currently available.
   7  *   Basic support for AG-AND chips is provided.
   8  *
   9  *      Additional technical information is available on
  10  *      http://www.linux-mtd.infradead.org/doc/nand.html
  11  *
  12  *  Copyright (C) 2000 Steven J. Hill (sjhill@realitydiluted.com)
  13  *                2002-2006 Thomas Gleixner (tglx@linutronix.de)
  14  *
  15  *  Credits:
  16  *      David Woodhouse for adding multichip support
  17  *
  18  *      Aleph One Ltd. and Toby Churchill Ltd. for supporting the
  19  *      rework for 2K page size chips
  20  *
  21  *  TODO:
  22  *      Enable cached programming for 2k page size chips
  23  *      Check, if mtd->ecctype should be set to MTD_ECC_HW
  24  *      if we have HW ecc support.
  25  *      The AG-AND chips have nice features for speed improvement,
  26  *      which are not supported yet. Read / program 4 pages in one go.
  27  *      BBT table is not serialized, has to be fixed
  28  *
  29  * This program is free software; you can redistribute it and/or modify
  30  * it under the terms of the GNU General Public License version 2 as
  31  * published by the Free Software Foundation.
  32  *
  33  */
  34
  35 #include <linux/module.h>
  36 #include <linux/delay.h>
  37 #include <linux/errno.h>
  38 #include <linux/err.h>
  39 #include <linux/sched.h>
  40 #include <linux/slab.h>
  41 #include <linux/types.h>
  42 #include <linux/mtd/mtd.h>
  43 #include <linux/mtd/nand.h>
  44 #include <linux/mtd/nand_ecc.h>
  45 #include <linux/interrupt.h>
  46 #include <linux/bitops.h>
  47 #include <linux/leds.h>
  48 #include <linux/io.h>
  49
  50 #ifdef CONFIG_MTD_PARTITIONS
  51 #include <linux/mtd/partitions.h>
  52 #endif
  53
  54 /* Define default oob placement schemes for large and small page devices */
  55 static struct nand_ecclayout nand_oob_8 = {
  56         .eccbytes = 3,
  57         .eccpos = {0, 1, 2},
  58         .oobfree = {
  59                 {.offset = 3,
  60                  .length = 2},
  61                 {.offset = 6,
  62                  .length = 2} }
  63 };
  64
  65 static struct nand_ecclayout nand_oob_16 = {
  66         .eccbytes = 6,
  67         .eccpos = {0, 1, 2, 3, 6, 7},
  68         .oobfree = {
  69                 {.offset = 8,
  70                  . length = 8} }
  71 };
  72
  73 static struct nand_ecclayout nand_oob_64 = {
  74         .eccbytes = 24,
  75         .eccpos = {
  76                    40, 41, 42, 43, 44, 45, 46, 47,
  77                    48, 49, 50, 51, 52, 53, 54, 55,
  78                    56, 57, 58, 59, 60, 61, 62, 63},
  79         .oobfree = {
  80                 {.offset = 2,
  81                  .length = 38} }
  82 };
  83
  84 static struct nand_ecclayout nand_oob_128 = {
  85         .eccbytes = 48,
  86         .eccpos = {
  87                    80, 81, 82, 83, 84, 85, 86, 87,
  88                    88, 89, 90, 91, 92, 93, 94, 95,
  89                    96, 97, 98, 99, 100, 101, 102, 103,
  90                    104, 105, 106, 107, 108, 109, 110, 111,
  91                    112, 113, 114, 115, 116, 117, 118, 119,
  92                    120, 121, 122, 123, 124, 125, 126, 127},
  93         .oobfree = {
  94                 {.offset = 2,
  95                  .length = 78} }
  96 };
  97
  98 static int nand_get_device(struct nand_chip *chip, struct mtd_info *mtd,
  99                            int new_state);
 100
 101 static int nand_do_write_oob(struct mtd_info *mtd, loff_t to,
 102                              struct mtd_oob_ops *ops);
 103
 104 /*
 105  * For devices which display every fart in the system on a separate LED. Is
 106  * compiled away when LED support is disabled.
 107  */
 108 DEFINE_LED_TRIGGER(nand_led_trigger);
 109
 110 static int check_offs_len(struct mtd_info *mtd,
 111                                         loff_t ofs, uint64_t len)
 112 {
 113         struct nand_chip *chip = mtd->priv;
 114         int ret = 0;
 115
 116         /* Start address must align on block boundary */
 117         if (ofs & ((1 << chip->phys_erase_shift) - 1)) {
 118                 DEBUG(MTD_DEBUG_LEVEL0, "%s: Unaligned address\n", __func__);
 119                 ret = -EINVAL;
 120         }
 121
 122         /* Length must align on block boundary */
 123         if (len & ((1 << chip->phys_erase_shift) - 1)) {
 124                 DEBUG(MTD_DEBUG_LEVEL0, "%s: Length not block aligned\n",
 125                                         __func__);
 126                 ret = -EINVAL;
 127         }
 128
 129         /* Do not allow past end of device */
 130         if (ofs + len > mtd->size) {
 131                 DEBUG(MTD_DEBUG_LEVEL0, "%s: Past end of device\n",
 132                                         __func__);
 133                 ret = -EINVAL;
 134         }
 135
 136         return ret;
 137 }
 138
 139 /**
 140  * nand_release_device - [GENERIC] release chip
 141  * @mtd:        MTD device structure
 142  *
 143  * Deselect, release chip lock and wake up anyone waiting on the device
 144  */
 145 static void nand_release_device(struct mtd_info *mtd)
 146 {
 147         struct nand_chip *chip = mtd->priv;
 148
 149         /* De-select the NAND device */
 150         chip->select_chip(mtd, -1);
 151
 152         /* Release the controller and the chip */
 153         spin_lock(&chip->controller->lock);
 154         chip->controller->active = NULL;
 155         chip->state = FL_READY;
 156         wake_up(&chip->controller->wq);
 157         spin_unlock(&chip->controller->lock);
 158 }
 159
 160 /**
 161  * nand_read_byte - [DEFAULT] read one byte from the chip
 162  * @mtd:        MTD device structure
 163  *
 164  * Default read function for 8bit buswith
 165  */
 166 static uint8_t nand_read_byte(struct mtd_info *mtd)
 167 {
 168         struct nand_chip *chip = mtd->priv;
 169         return readb(chip->IO_ADDR_R);
 170 }
 171
 172 /**
 173  * nand_read_byte16 - [DEFAULT] read one byte endianess aware from the chip
 174  * @mtd:        MTD device structure
 175  *
 176  * Default read function for 16bit buswith with
 177  * endianess conversion
 178  */
 179 static uint8_t nand_read_byte16(struct mtd_info *mtd)
 180 {
 181         struct nand_chip *chip = mtd->priv;
 182         return (uint8_t) cpu_to_le16(readw(chip->IO_ADDR_R));
 183 }
 184
 185 /**
 186  * nand_read_word - [DEFAULT] read one word from the chip
 187  * @mtd:        MTD device structure
 188  *
 189  * Default read function for 16bit buswith without
 190  * endianess conversion
 191  */
 192 static u16 nand_read_word(struct mtd_info *mtd)
 193 {
 194         struct nand_chip *chip = mtd->priv;
 195         return readw(chip->IO_ADDR_R);
 196 }
 197
 198 /**
 199  * nand_select_chip - [DEFAULT] control CE line
 200  * @mtd:        MTD device structure
 201  * @chipnr:     chipnumber to select, -1 for deselect
 202  *
 203  * Default select function for 1 chip devices.
 204  */
 205 static void nand_select_chip(struct mtd_info *mtd, int chipnr)
 206 {
 207         struct nand_chip *chip = mtd->priv;
 208
 209         switch (chipnr) {
 210         case -1:
 211                 chip->cmd_ctrl(mtd, NAND_CMD_NONE, 0 | NAND_CTRL_CHANGE);
 212                 break;
 213         case 0:
 214                 break;
 215
 216         default:
 217                 BUG();
 218         }
 219 }
 220
 221 /**
 222  * nand_write_buf - [DEFAULT] write buffer to chip
 223  * @mtd:        MTD device structure
 224  * @buf:        data buffer
 225  * @len:        number of bytes to write
 226  *
 227  * Default write function for 8bit buswith
 228  */
 229 static void nand_write_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
 230 {
 231         int i;
 232         struct nand_chip *chip = mtd->priv;
 233
 234         for (i = 0; i < len; i++)
 235                 writeb(buf[i], chip->IO_ADDR_W);
 236 }
 237
 238 /**
 239  * nand_read_buf - [DEFAULT] read chip data into buffer
 240  * @mtd:        MTD device structure
 241  * @buf:        buffer to store date
 242  * @len:        number of bytes to read
 243  *
 244  * Default read function for 8bit buswith
 245  */
 246 static void nand_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
 247 {
 248         int i;
 249         struct nand_chip *chip = mtd->priv;
 250
 251         for (i = 0; i < len; i++)
 252                 buf[i] = readb(chip->IO_ADDR_R);
 253 }
 254
 255 /**
 256  * nand_verify_buf - [DEFAULT] Verify chip data against buffer
 257  * @mtd:        MTD device structure
 258  * @buf:        buffer containing the data to compare
 259  * @len:        number of bytes to compare
 260  *
 261  * Default verify function for 8bit buswith
 262  */
 263 static int nand_verify_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
 264 {
 265         int i;
 266         struct nand_chip *chip = mtd->priv;
 267
 268         for (i = 0; i < len; i++)
 269                 if (buf[i] != readb(chip->IO_ADDR_R))
 270                         return -EFAULT;
 271         return 0;
 272 }
 273
 274 /**
 275  * nand_write_buf16 - [DEFAULT] write buffer to chip
 276  * @mtd:        MTD device structure
 277  * @buf:        data buffer
 278  * @len:        number of bytes to write
 279  *
 280  * Default write function for 16bit buswith
 281  */
 282 static void nand_write_buf16(struct mtd_info *mtd, const uint8_t *buf, int len)
 283 {
 284         int i;
 285         struct nand_chip *chip = mtd->priv;
 286         u16 *p = (u16 *) buf;
 287         len >>= 1;
 288
 289         for (i = 0; i < len; i++)
 290                 writew(p[i], chip->IO_ADDR_W);
 291
 292 }
 293
 294 /**
 295  * nand_read_buf16 - [DEFAULT] read chip data into buffer
 296  * @mtd:        MTD device structure
 297  * @buf:        buffer to store date
 298  * @len:        number of bytes to read
 299  *
 300  * Default read function for 16bit buswith
 301  */
 302 static void nand_read_buf16(struct mtd_info *mtd, uint8_t *buf, int len)
 303 {
 304         int i;
 305         struct nand_chip *chip = mtd->priv;
 306         u16 *p = (u16 *) buf;
 307         len >>= 1;
 308
 309         for (i = 0; i < len; i++)
 310                 p[i] = readw(chip->IO_ADDR_R);
 311 }
 312
 313 /**
 314  * nand_verify_buf16 - [DEFAULT] Verify chip data against buffer
 315  * @mtd:        MTD device structure
 316  * @buf:        buffer containing the data to compare
 317  * @len:        number of bytes to compare
 318  *
 319  * Default verify function for 16bit buswith
 320  */
 321 static int nand_verify_buf16(struct mtd_info *mtd, const uint8_t *buf, int len)
 322 {
 323         int i;
 324         struct nand_chip *chip = mtd->priv;
 325         u16 *p = (u16 *) buf;
 326         len >>= 1;
 327
 328         for (i = 0; i < len; i++)
 329                 if (p[i] != readw(chip->IO_ADDR_R))
 330                         return -EFAULT;
 331
 332         return 0;
 333 }
 334
 335 /**
 336  * nand_block_bad - [DEFAULT] Read bad block marker from the chip
 337  * @mtd:        MTD device structure
 338  * @ofs:        offset from device start
 339  * @getchip:    0, if the chip is already selected
 340  *
 341  * Check, if the block is bad.
 342  */
 343 static int nand_block_bad(struct mtd_info *mtd, loff_t ofs, int getchip)
 344 {
 345         int page, chipnr, res = 0;
 346         struct nand_chip *chip = mtd->priv;
 347         u16 bad;
 348
 349         if (chip->options & NAND_BBT_SCANLASTPAGE)
 350                 ofs += mtd->erasesize - mtd->writesize;
 351
 352         page = (int)(ofs >> chip->page_shift) & chip->pagemask;
 353
 354         if (getchip) {
 355                 chipnr = (int)(ofs >> chip->chip_shift);
 356
 357                 nand_get_device(chip, mtd, FL_READING);
 358
 359                 /* Select the NAND device */
 360                 chip->select_chip(mtd, chipnr);
 361         }
 362
 363         if (chip->options & NAND_BUSWIDTH_16) {
 364                 chip->cmdfunc(mtd, NAND_CMD_READOOB, chip->badblockpos & 0xFE,
 365                               page);
 366                 bad = cpu_to_le16(chip->read_word(mtd));
 367                 if (chip->badblockpos & 0x1)
 368                         bad >>= 8;
 369                 else
 370                         bad &= 0xFF;
 371         } else {
 372                 chip->cmdfunc(mtd, NAND_CMD_READOOB, chip->badblockpos, page);
 373                 bad = chip->read_byte(mtd);
 374         }
 375
 376         if (likely(chip->badblockbits == 8))
 377                 res = bad != 0xFF;
 378         else
 379                 res = hweight8(bad) < chip->badblockbits;
 380
 381         if (getchip)
 382                 nand_release_device(mtd);
 383
 384         return res;
 385 }
 386
 387 /**
 388  * nand_default_block_markbad - [DEFAULT] mark a block bad
 389  * @mtd:        MTD device structure
 390  * @ofs:        offset from device start
 391  *
 392  * This is the default implementation, which can be overridden by
 393  * a hardware specific driver.
 394 */
 395 static int nand_default_block_markbad(struct mtd_info *mtd, loff_t ofs)
 396 {
 397         struct nand_chip *chip = mtd->priv;
 398         uint8_t buf[2] = { 0, 0 };
 399         int block, ret, i = 0;
 400
 401         if (chip->options & NAND_BBT_SCANLASTPAGE)
 402                 ofs += mtd->erasesize - mtd->writesize;
 403
 404         /* Get block number */
 405         block = (int)(ofs >> chip->bbt_erase_shift);
 406         if (chip->bbt)
 407                 chip->bbt[block >> 2] |= 0x01 << ((block & 0x03) << 1);
 408
 409         /* Do we have a flash based bad block table ? */
 410         if (chip->options & NAND_USE_FLASH_BBT)
 411                 ret = nand_update_bbt(mtd, ofs);
 412         else {
 413                 nand_get_device(chip, mtd, FL_WRITING);
 414
 415                 /* Write to first two pages and to byte 1 and 6 if necessary.
 416                  * If we write to more than one location, the first error
 417                  * encountered quits the procedure. We write two bytes per
 418                  * location, so we dont have to mess with 16 bit access.
 419                  */
 420                 do {
 421                         chip->ops.len = chip->ops.ooblen = 2;
 422                         chip->ops.datbuf = NULL;
 423                         chip->ops.oobbuf = buf;
 424                         chip->ops.ooboffs = chip->badblockpos & ~0x01;
 425
 426                         ret = nand_do_write_oob(mtd, ofs, &chip->ops);
 427
 428                         if (!ret && (chip->options & NAND_BBT_SCANBYTE1AND6)) {
 429                                 chip->ops.ooboffs = NAND_SMALL_BADBLOCK_POS
 430                                         & ~0x01;
 431                                 ret = nand_do_write_oob(mtd, ofs, &chip->ops);
 432                         }
 433                         i++;
 434                         ofs += mtd->writesize;
 435                 } while (!ret && (chip->options & NAND_BBT_SCAN2NDPAGE) &&
 436                                 i < 2);
 437
 438                 nand_release_device(mtd);
 439         }
 440         if (!ret)
 441                 mtd->ecc_stats.badblocks++;
 442
 443         return ret;
 444 }
 445
 446 /**
 447  * nand_check_wp - [GENERIC] check if the chip is write protected
 448  * @mtd:        MTD device structure
 449  * Check, if the device is write protected
 450  *
 451  * The function expects, that the device is already selected
 452  */
 453 static int nand_check_wp(struct mtd_info *mtd)
 454 {
 455         struct nand_chip *chip = mtd->priv;
 456
 457         /* broken xD cards report WP despite being writable */
 458         if (chip->options & NAND_BROKEN_XD)
 459                 return 0;
 460
 461         /* Check the WP bit */
 462         chip->cmdfunc(mtd, NAND_CMD_STATUS, -1, -1);
 463         return (chip->read_byte(mtd) & NAND_STATUS_WP) ? 0 : 1;
 464 }
 465
 466 /**
 467  * nand_block_checkbad - [GENERIC] Check if a block is marked bad
 468  * @mtd:        MTD device structure
 469  * @ofs:        offset from device start
 470  * @getchip:    0, if the chip is already selected
 471  * @allowbbt:   1, if its allowed to access the bbt area
 472  *
 473  * Check, if the block is bad. Either by reading the bad block table or
 474  * calling of the scan function.
 475  */
 476 static int nand_block_checkbad(struct mtd_info *mtd, loff_t ofs, int getchip,
 477                                int allowbbt)
 478 {
 479         struct nand_chip *chip = mtd->priv;
 480
 481         if (!chip->bbt)
 482                 return chip->block_bad(mtd, ofs, getchip);
 483
 484         /* Return info from the table */
 485         return nand_isbad_bbt(mtd, ofs, allowbbt);
 486 }
 487
 488 /**
 489  * panic_nand_wait_ready - [GENERIC] Wait for the ready pin after commands.
 490  * @mtd:        MTD device structure
 491  * @timeo:      Timeout
 492  *
 493  * Helper function for nand_wait_ready used when needing to wait in interrupt
 494  * context.
 495  */
 496 static void panic_nand_wait_ready(struct mtd_info *mtd, unsigned long timeo)
 497 {
 498         struct nand_chip *chip = mtd->priv;
 499         int i;
 500
 501         /* Wait for the device to get ready */
 502         for (i = 0; i < timeo; i++) {
 503                 if (chip->dev_ready(mtd))
 504                         break;
 505                 touch_softlockup_watchdog();
 506                 mdelay(1);
 507         }
 508 }
 509
 510 /*
 511  * Wait for the ready pin, after a command
 512  * The timeout is catched later.
 513  */
 514 void nand_wait_ready(struct mtd_info *mtd)
 515 {
 516         struct nand_chip *chip = mtd->priv;
 517         unsigned long timeo = jiffies + 2;
 518
 519         /* 400ms timeout */
 520         if (in_interrupt() || oops_in_progress)
 521                 return panic_nand_wait_ready(mtd, 400);
 522
 523         led_trigger_event(nand_led_trigger, LED_FULL);
 524         /* wait until command is processed or timeout occures */
 525         do {
 526                 if (chip->dev_ready(mtd))
 527                         break;
 528                 touch_softlockup_watchdog();
 529         } while (time_before(jiffies, timeo));
 530         led_trigger_event(nand_led_trigger, LED_OFF);
 531 }
 532 EXPORT_SYMBOL_GPL(nand_wait_ready);
 533
 534 /**
 535  * nand_command - [DEFAULT] Send command to NAND device
 536  * @mtd:        MTD device structure
 537  * @command:    the command to be sent
 538  * @column:     the column address for this command, -1 if none
 539  * @page_addr:  the page address for this command, -1 if none
 540  *
 541  * Send command to NAND device. This function is used for small page
 542  * devices (256/512 Bytes per page)
 543  */
 544 static void nand_command(struct mtd_info *mtd, unsigned int command,
 545                          int column, int page_addr)
 546 {
 547         register struct nand_chip *chip = mtd->priv;
 548         int ctrl = NAND_CTRL_CLE | NAND_CTRL_CHANGE;
 549
 550         /*
 551          * Write out the command to the device.
 552          */
 553         if (command == NAND_CMD_SEQIN) {
 554                 int readcmd;
 555
 556                 if (column >= mtd->writesize) {
 557                         /* OOB area */
 558                         column -= mtd->writesize;
 559                         readcmd = NAND_CMD_READOOB;
 560                 } else if (column < 256) {
 561                         /* First 256 bytes --> READ0 */
 562                         readcmd = NAND_CMD_READ0;
 563                 } else {
 564                         column -= 256;
 565                         readcmd = NAND_CMD_READ1;
 566                 }
 567                 chip->cmd_ctrl(mtd, readcmd, ctrl);
 568                 ctrl &= ~NAND_CTRL_CHANGE;
 569         }
 570         chip->cmd_ctrl(mtd, command, ctrl);
 571
 572         /*
 573          * Address cycle, when necessary
 574          */
 575         ctrl = NAND_CTRL_ALE | NAND_CTRL_CHANGE;
 576         /* Serially input address */
 577         if (column != -1) {
 578                 /* Adjust columns for 16 bit buswidth */
 579                 if (chip->options & NAND_BUSWIDTH_16)
 580                         column >>= 1;
 581                 chip->cmd_ctrl(mtd, column, ctrl);
 582                 ctrl &= ~NAND_CTRL_CHANGE;
 583         }
 584         if (page_addr != -1) {
 585                 chip->cmd_ctrl(mtd, page_addr, ctrl);
 586                 ctrl &= ~NAND_CTRL_CHANGE;
 587                 chip->cmd_ctrl(mtd, page_addr >> 8, ctrl);
 588                 /* One more address cycle for devices > 32MiB */
 589                 if (chip->chipsize > (32 << 20))
 590                         chip->cmd_ctrl(mtd, page_addr >> 16, ctrl);
 591         }
 592         chip->cmd_ctrl(mtd, NAND_CMD_NONE, NAND_NCE | NAND_CTRL_CHANGE);
 593
 594         /*
 595          * program and erase have their own busy handlers
 596          * status and sequential in needs no delay
 597          */
 598         switch (command) {
 599
 600         case NAND_CMD_PAGEPROG:
 601         case NAND_CMD_ERASE1:
 602         case NAND_CMD_ERASE2:
 603         case NAND_CMD_SEQIN:
 604         case NAND_CMD_STATUS:
 605                 return;
 606
 607         case NAND_CMD_RESET:
 608                 if (chip->dev_ready)
 609                         break;
 610                 udelay(chip->chip_delay);
 611                 chip->cmd_ctrl(mtd, NAND_CMD_STATUS,
 612                                NAND_CTRL_CLE | NAND_CTRL_CHANGE);
 613                 chip->cmd_ctrl(mtd,
 614                                NAND_CMD_NONE, NAND_NCE | NAND_CTRL_CHANGE);
 615                 while (!(chip->read_byte(mtd) & NAND_STATUS_READY))
 616                                 ;
 617                 return;
 618
 619                 /* This applies to read commands */
 620         default:
 621                 /*
 622                  * If we don't have access to the busy pin, we apply the given
 623                  * command delay
 624                  */
 625                 if (!chip->dev_ready) {
 626                         udelay(chip->chip_delay);
 627                         return;
 628                 }
 629         }
 630         /* Apply this short delay always to ensure that we do wait tWB in
 631          * any case on any machine. */
 632         ndelay(100);
 633
 634         nand_wait_ready(mtd);
 635 }
 636
 637 /**
 638  * nand_command_lp - [DEFAULT] Send command to NAND large page device
 639  * @mtd:        MTD device structure
 640  * @command:    the command to be sent
 641  * @column:     the column address for this command, -1 if none
 642  * @page_addr:  the page address for this command, -1 if none
 643  *
 644  * Send command to NAND device. This is the version for the new large page
 645  * devices We dont have the separate regions as we have in the small page
 646  * devices.  We must emulate NAND_CMD_READOOB to keep the code compatible.
 647  */
 648 static void nand_command_lp(struct mtd_info *mtd, unsigned int command,
 649                             int column, int page_addr)
 650 {
 651         register struct nand_chip *chip = mtd->priv;
 652
 653         /* Emulate NAND_CMD_READOOB */
 654         if (command == NAND_CMD_READOOB) {
 655                 column += mtd->writesize;
 656                 command = NAND_CMD_READ0;
 657         }
 658
 659         /* Command latch cycle */
 660         chip->cmd_ctrl(mtd, command & 0xff,
 661                        NAND_NCE | NAND_CLE | NAND_CTRL_CHANGE);
 662
 663         if (column != -1 || page_addr != -1) {
 664                 int ctrl = NAND_CTRL_CHANGE | NAND_NCE | NAND_ALE;
 665
 666                 /* Serially input address */
 667                 if (column != -1) {
 668                         /* Adjust columns for 16 bit buswidth */
 669                         if (chip->options & NAND_BUSWIDTH_16)
 670                                 column >>= 1;
 671                         chip->cmd_ctrl(mtd, column, ctrl);
 672                         ctrl &= ~NAND_CTRL_CHANGE;
 673                         chip->cmd_ctrl(mtd, column >> 8, ctrl);
 674                 }
 675                 if (page_addr != -1) {
 676                         chip->cmd_ctrl(mtd, page_addr, ctrl);
 677                         chip->cmd_ctrl(mtd, page_addr >> 8,
 678                                        NAND_NCE | NAND_ALE);
 679                         /* One more address cycle for devices > 128MiB */
 680                         if (chip->chipsize > (128 << 20))
 681                                 chip->cmd_ctrl(mtd, page_addr >> 16,
 682                                                NAND_NCE | NAND_ALE);
 683                 }
 684         }
 685         chip->cmd_ctrl(mtd, NAND_CMD_NONE, NAND_NCE | NAND_CTRL_CHANGE);
 686
 687         /*
 688          * program and erase have their own busy handlers
 689          * status, sequential in, and deplete1 need no delay
 690          */
 691         switch (command) {
 692
 693         case NAND_CMD_CACHEDPROG:
 694         case NAND_CMD_PAGEPROG:
 695         case NAND_CMD_ERASE1:
 696         case NAND_CMD_ERASE2:
 697         case NAND_CMD_SEQIN:
 698         case NAND_CMD_RNDIN:
 699         case NAND_CMD_STATUS:
 700         case NAND_CMD_DEPLETE1:
 701                 return;
 702
 703                 /*
 704                  * read error status commands require only a short delay
 705                  */
 706         case NAND_CMD_STATUS_ERROR:
 707         case NAND_CMD_STATUS_ERROR0:
 708         case NAND_CMD_STATUS_ERROR1:
 709         case NAND_CMD_STATUS_ERROR2:
 710         case NAND_CMD_STATUS_ERROR3:
 711                 udelay(chip->chip_delay);
 712                 return;
 713
 714         case NAND_CMD_RESET:
 715                 if (chip->dev_ready)
 716                         break;
 717                 udelay(chip->chip_delay);
 718                 chip->cmd_ctrl(mtd, NAND_CMD_STATUS,
 719                                NAND_NCE | NAND_CLE | NAND_CTRL_CHANGE);
 720                 chip->cmd_ctrl(mtd, NAND_CMD_NONE,
 721                                NAND_NCE | NAND_CTRL_CHANGE);
 722                 while (!(chip->read_byte(mtd) & NAND_STATUS_READY))
 723                                 ;
 724                 return;
 725
 726         case NAND_CMD_RNDOUT:
 727                 /* No ready / busy check necessary */
 728                 chip->cmd_ctrl(mtd, NAND_CMD_RNDOUTSTART,
 729                                NAND_NCE | NAND_CLE | NAND_CTRL_CHANGE);
 730                 chip->cmd_ctrl(mtd, NAND_CMD_NONE,
 731                                NAND_NCE | NAND_CTRL_CHANGE);
 732                 return;
 733
 734         case NAND_CMD_READ0:
 735                 chip->cmd_ctrl(mtd, NAND_CMD_READSTART,
 736                                NAND_NCE | NAND_CLE | NAND_CTRL_CHANGE);
 737                 chip->cmd_ctrl(mtd, NAND_CMD_NONE,
 738                                NAND_NCE | NAND_CTRL_CHANGE);
 739
 740                 /* This applies to read commands */
 741         default:
 742                 /*
 743                  * If we don't have access to the busy pin, we apply the given
 744                  * command delay
 745                  */
 746                 if (!chip->dev_ready) {
 747                         udelay(chip->chip_delay);
 748                         return;
 749                 }
 750         }
 751
 752         /* Apply this short delay always to ensure that we do wait tWB in
 753          * any case on any machine. */
 754         ndelay(100);
 755
 756         nand_wait_ready(mtd);
 757 }
 758
 759 /**
 760  * panic_nand_get_device - [GENERIC] Get chip for selected access
 761  * @chip:       the nand chip descriptor
 762  * @mtd:        MTD device structure
 763  * @new_state:  the state which is requested
 764  *
 765  * Used when in panic, no locks are taken.
 766  */
 767 static void panic_nand_get_device(struct nand_chip *chip,
 768                       struct mtd_info *mtd, int new_state)
 769 {
 770         /* Hardware controller shared among independend devices */
 771         chip->controller->active = chip;
 772         chip->state = new_state;
 773 }
 774
 775 /**
 776  * nand_get_device - [GENERIC] Get chip for selected access
 777  * @chip:       the nand chip descriptor
 778  * @mtd:        MTD device structure
 779  * @new_state:  the state which is requested
 780  *
 781  * Get the device and lock it for exclusive access
 782  */
 783 static int
 784 nand_get_device(struct nand_chip *chip, struct mtd_info *mtd, int new_state)
 785 {
 786         spinlock_t *lock = &chip->controller->lock;
 787         wait_queue_head_t *wq = &chip->controller->wq;
 788         DECLARE_WAITQUEUE(wait, current);
 789 retry:
 790         spin_lock(lock);
 791
 792         /* Hardware controller shared among independent devices */
 793         if (!chip->controller->active)
 794                 chip->controller->active = chip;
 795
 796         if (chip->controller->active == chip && chip->state == FL_READY) {
 797                 chip->state = new_state;
 798                 spin_unlock(lock);
 799                 return 0;
 800         }
 801         if (new_state == FL_PM_SUSPENDED) {
 802                 if (chip->controller->active->state == FL_PM_SUSPENDED) {
 803                         chip->state = FL_PM_SUSPENDED;
 804                         spin_unlock(lock);
 805                         return 0;
 806                 }
 807         }
 808         set_current_state(TASK_UNINTERRUPTIBLE);
 809         add_wait_queue(wq, &wait);
 810         spin_unlock(lock);
 811         schedule();
 812         remove_wait_queue(wq, &wait);
 813         goto retry;
 814 }
 815
 816 /**
 817  * panic_nand_wait - [GENERIC]  wait until the command is done
 818  * @mtd:        MTD device structure
 819  * @chip:       NAND chip structure
 820  * @timeo:      Timeout
 821  *
 822  * Wait for command done. This is a helper function for nand_wait used when
 823  * we are in interrupt context. May happen when in panic and trying to write
 824  * an oops trough mtdoops.
 825  */
 826 static void panic_nand_wait(struct mtd_info *mtd, struct nand_chip *chip,
 827                             unsigned long timeo)
 828 {
 829         int i;
 830         for (i = 0; i < timeo; i++) {
 831                 if (chip->dev_ready) {
 832                         if (chip->dev_ready(mtd))
 833                                 break;
 834                 } else {
 835                         if (chip->read_byte(mtd) & NAND_STATUS_READY)
 836                                 break;
 837                 }
 838                 mdelay(1);
 839         }
 840 }
 841
 842 /**
 843  * nand_wait - [DEFAULT]  wait until the command is done
 844  * @mtd:        MTD device structure
 845  * @chip:       NAND chip structure
 846  *
 847  * Wait for command done. This applies to erase and program only
 848  * Erase can take up to 400ms and program up to 20ms according to
 849  * general NAND and SmartMedia specs
 850  */
 851 static int nand_wait(struct mtd_info *mtd, struct nand_chip *chip)
 852 {
 853
 854         unsigned long timeo = jiffies;
 855         int status, state = chip->state;
 856
 857         if (state == FL_ERASING)
 858                 timeo += (HZ * 400) / 1000;
 859         else
 860                 timeo += (HZ * 20) / 1000;
 861
 862         led_trigger_event(nand_led_trigger, LED_FULL);
 863
 864         /* Apply this short delay always to ensure that we do wait tWB in
 865          * any case on any machine. */
 866         ndelay(100);
 867
 868         if ((state == FL_ERASING) && (chip->options & NAND_IS_AND))
 869                 chip->cmdfunc(mtd, NAND_CMD_STATUS_MULTI, -1, -1);
 870         else
 871                 chip->cmdfunc(mtd, NAND_CMD_STATUS, -1, -1);
 872
 873         if (in_interrupt() || oops_in_progress)
 874                 panic_nand_wait(mtd, chip, timeo);
 875         else {
 876                 while (time_before(jiffies, timeo)) {
 877                         if (chip->dev_ready) {
 878                                 if (chip->dev_ready(mtd))
 879                                         break;
 880                         } else {
 881                                 if (chip->read_byte(mtd) & NAND_STATUS_READY)
 882                                         break;
 883                         }
 884                         cond_resched();
 885                 }
 886         }
 887         led_trigger_event(nand_led_trigger, LED_OFF);
 888
 889         status = (int)chip->read_byte(mtd);
 890         return status;
 891 }
 892
 893 /**
 894  * __nand_unlock - [REPLACEABLE] unlocks specified locked blocks
 895  *
 896  * @mtd: mtd info
 897  * @ofs: offset to start unlock from
 898  * @len: length to unlock
 899  * @invert:   when = 0, unlock the range of blocks within the lower and
 900  *                      upper boundary address
 901  *            when = 1, unlock the range of blocks outside the boundaries
 902  *                      of the lower and upper boundary address
 903  *
 904  * return - unlock status
 905  */
 906 static int __nand_unlock(struct mtd_info *mtd, loff_t ofs,
 907                                         uint64_t len, int invert)
 908 {
 909         int ret = 0;
 910         int status, page;
 911         struct nand_chip *chip = mtd->priv;
 912
 913         /* Submit address of first page to unlock */
 914         page = ofs >> chip->page_shift;
 915         chip->cmdfunc(mtd, NAND_CMD_UNLOCK1, -1, page & chip->pagemask);
 916
 917         /* Submit address of last page to unlock */
 918         page = (ofs + len) >> chip->page_shift;
 919         chip->cmdfunc(mtd, NAND_CMD_UNLOCK2, -1,
 920                                 (page | invert) & chip->pagemask);
 921
 922         /* Call wait ready function */
 923         status = chip->waitfunc(mtd, chip);
 924         udelay(1000);
 925         /* See if device thinks it succeeded */
 926         if (status & 0x01) {
 927                 DEBUG(MTD_DEBUG_LEVEL0, "%s: Error status = 0x%08x\n",
 928                                         __func__, status);
 929                 ret = -EIO;
 930         }
 931
 932         return ret;
 933 }
 934
 935 /**
 936  * nand_unlock - [REPLACEABLE] unlocks specified locked blocks
 937  *
 938  * @mtd: mtd info
 939  * @ofs: offset to start unlock from
 940  * @len: length to unlock
 941  *
 942  * return - unlock status
 943  */
 944 int nand_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
 945 {
 946         int ret = 0;
 947         int chipnr;
 948         struct nand_chip *chip = mtd->priv;
 949
 950         DEBUG(MTD_DEBUG_LEVEL3, "%s: start = 0x%012llx, len = %llu\n",
 951                         __func__, (unsigned long long)ofs, len);
 952
 953         if (check_offs_len(mtd, ofs, len))
 954                 ret = -EINVAL;
 955
 956         /* Align to last block address if size addresses end of the device */
 957         if (ofs + len == mtd->size)
 958                 len -= mtd->erasesize;
 959
 960         nand_get_device(chip, mtd, FL_UNLOCKING);
 961
 962         /* Shift to get chip number */
 963         chipnr = ofs >> chip->chip_shift;
 964
 965         chip->select_chip(mtd, chipnr);
 966
 967         /* Check, if it is write protected */
 968         if (nand_check_wp(mtd)) {
 969                 DEBUG(MTD_DEBUG_LEVEL0, "%s: Device is write protected!!!\n",
 970                                         __func__);
 971                 ret = -EIO;
 972                 goto out;
 973         }
 974
 975         ret = __nand_unlock(mtd, ofs, len, 0);
 976
 977 out:
 978         /* de-select the NAND device */
 979         chip->select_chip(mtd, -1);
 980
 981         nand_release_device(mtd);
 982
 983         return ret;
 984 }
 985 EXPORT_SYMBOL(nand_unlock);
 986
 987 /**
 988  * nand_lock - [REPLACEABLE] locks all blocks present in the device
 989  *
 990  * @mtd: mtd info
 991  * @ofs: offset to start unlock from
 992  * @len: length to unlock
 993  *
 994  * return - lock status
 995  *
 996  * This feature is not supported in many NAND parts. 'Micron' NAND parts
 997  * do have this feature, but it allows only to lock all blocks, not for
 998  * specified range for block.
 999  *
1000  * Implementing 'lock' feature by making use of 'unlock', for now.
1001  */
1002 int nand_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
1003 {
1004         int ret = 0;
1005         int chipnr, status, page;
1006         struct nand_chip *chip = mtd->priv;
1007
1008         DEBUG(MTD_DEBUG_LEVEL3, "%s: start = 0x%012llx, len = %llu\n",
1009                         __func__, (unsigned long long)ofs, len);
1010
1011         if (check_offs_len(mtd, ofs, len))
1012                 ret = -EINVAL;
1013
1014         nand_get_device(chip, mtd, FL_LOCKING);
1015
1016         /* Shift to get chip number */
1017         chipnr = ofs >> chip->chip_shift;
1018
1019         chip->select_chip(mtd, chipnr);
1020
1021         /* Check, if it is write protected */
1022         if (nand_check_wp(mtd)) {
1023                 DEBUG(MTD_DEBUG_LEVEL0, "%s: Device is write protected!!!\n",
1024                                         __func__);
1025                 status = MTD_ERASE_FAILED;
1026                 ret = -EIO;
1027                 goto out;
1028         }
1029
1030         /* Submit address of first page to lock */
1031         page = ofs >> chip->page_shift;
1032         chip->cmdfunc(mtd, NAND_CMD_LOCK, -1, page & chip->pagemask);
1033
1034         /* Call wait ready function */
1035         status = chip->waitfunc(mtd, chip);
1036         udelay(1000);
1037         /* See if device thinks it succeeded */
1038         if (status & 0x01) {
1039                 DEBUG(MTD_DEBUG_LEVEL0, "%s: Error status = 0x%08x\n",
1040                                         __func__, status);
1041                 ret = -EIO;
1042                 goto out;
1043         }
1044
1045         ret = __nand_unlock(mtd, ofs, len, 0x1);
1046
1047 out:
1048         /* de-select the NAND device */
1049         chip->select_chip(mtd, -1);
1050
1051         nand_release_device(mtd);
1052
1053         return ret;
1054 }
1055 EXPORT_SYMBOL(nand_lock);
1056
1057 /**
1058  * nand_read_page_raw - [Intern] read raw page data without ecc
1059  * @mtd:        mtd info structure
1060  * @chip:       nand chip info structure
1061  * @buf:        buffer to store read data
1062  * @page:       page number to read
1063  *
1064  * Not for syndrome calculating ecc controllers, which use a special oob layout
1065  */
1066 static int nand_read_page_raw(struct mtd_info *mtd, struct nand_chip *chip,
1067                               uint8_t *buf, int page)
1068 {
1069         chip->read_buf(mtd, buf, mtd->writesize);
1070         chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
1071         return 0;
1072 }
1073
1074 /**
1075  * nand_read_page_raw_syndrome - [Intern] read raw page data without ecc
1076  * @mtd:        mtd info structure
1077  * @chip:       nand chip info structure
1078  * @buf:        buffer to store read data
1079  * @page:       page number to read
1080  *
1081  * We need a special oob layout and handling even when OOB isn't used.
1082  */
1083 static int nand_read_page_raw_syndrome(struct mtd_info *mtd,
1084                                         struct nand_chip *chip,
1085                                         uint8_t *buf, int page)
1086 {
1087         int eccsize = chip->ecc.size;
1088         int eccbytes = chip->ecc.bytes;
1089         uint8_t *oob = chip->oob_poi;
1090         int steps, size;
1091
1092         for (steps = chip->ecc.steps; steps > 0; steps--) {
1093                 chip->read_buf(mtd, buf, eccsize);
1094                 buf += eccsize;
1095
1096                 if (chip->ecc.prepad) {
1097                         chip->read_buf(mtd, oob, chip->ecc.prepad);
1098                         oob += chip->ecc.prepad;
1099                 }
1100
1101                 chip->read_buf(mtd, oob, eccbytes);
1102                 oob += eccbytes;
1103
1104                 if (chip->ecc.postpad) {
1105                         chip->read_buf(mtd, oob, chip->ecc.postpad);
1106                         oob += chip->ecc.postpad;
1107                 }
1108         }
1109
1110         size = mtd->oobsize - (oob - chip->oob_poi);
1111         if (size)
1112                 chip->read_buf(mtd, oob, size);
1113
1114         return 0;
1115 }
1116
1117 /**
1118  * nand_read_page_swecc - [REPLACABLE] software ecc based page read function
1119  * @mtd:        mtd info structure
1120  * @chip:       nand chip info structure
1121  * @buf:        buffer to store read data
1122  * @page:       page number to read
1123  */
1124 static int nand_read_page_swecc(struct mtd_info *mtd, struct nand_chip *chip,
1125                                 uint8_t *buf, int page)
1126 {
1127         int i, eccsize = chip->ecc.size;
1128         int eccbytes = chip->ecc.bytes;
1129         int eccsteps = chip->ecc.steps;
1130         uint8_t *p = buf;
1131         uint8_t *ecc_calc = chip->buffers->ecccalc;
1132         uint8_t *ecc_code = chip->buffers->ecccode;
1133         uint32_t *eccpos = chip->ecc.layout->eccpos;
1134
1135         chip->ecc.read_page_raw(mtd, chip, buf, page);
1136
1137         for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize)
1138                 chip->ecc.calculate(mtd, p, &ecc_calc[i]);
1139
1140         for (i = 0; i < chip->ecc.total; i++)
1141                 ecc_code[i] = chip->oob_poi[eccpos[i]];
1142
1143         eccsteps = chip->ecc.steps;
1144         p = buf;
1145
1146         for (i = 0 ; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
1147                 int stat;
1148
1149                 stat = chip->ecc.correct(mtd, p, &ecc_code[i], &ecc_calc[i]);
1150                 if (stat < 0)
1151                         mtd->ecc_stats.failed++;
1152                 else
1153                         mtd->ecc_stats.corrected += stat;
1154         }
1155         return 0;
1156 }
1157
1158 /**
1159  * nand_read_subpage - [REPLACABLE] software ecc based sub-page read function
1160  * @mtd:        mtd info structure
1161  * @chip:       nand chip info structure
1162  * @data_offs:  offset of requested data within the page
1163  * @readlen:    data length
1164  * @bufpoi:     buffer to store read data
1165  */
1166 static int nand_read_subpage(struct mtd_info *mtd, struct nand_chip *chip,
1167                         uint32_t data_offs, uint32_t readlen, uint8_t *bufpoi)
1168 {
1169         int start_step, end_step, num_steps;
1170         uint32_t *eccpos = chip->ecc.layout->eccpos;
1171         uint8_t *p;
1172         int data_col_addr, i, gaps = 0;
1173         int datafrag_len, eccfrag_len, aligned_len, aligned_pos;
1174         int busw = (chip->options & NAND_BUSWIDTH_16) ? 2 : 1;
1175         int index = 0;
1176
1177         /* Column address wihin the page aligned to ECC size (256bytes). */
1178         start_step = data_offs / chip->ecc.size;
1179         end_step = (data_offs + readlen - 1) / chip->ecc.size;
1180         num_steps = end_step - start_step + 1;
1181
1182         /* Data size aligned to ECC ecc.size*/
1183         datafrag_len = num_steps * chip->ecc.size;
1184         eccfrag_len = num_steps * chip->ecc.bytes;
1185
1186         data_col_addr = start_step * chip->ecc.size;
1187         /* If we read not a page aligned data */
1188         if (data_col_addr != 0)
1189                 chip->cmdfunc(mtd, NAND_CMD_RNDOUT, data_col_addr, -1);
1190
1191         p = bufpoi + data_col_addr;
1192         chip->read_buf(mtd, p, datafrag_len);
1193
1194         /* Calculate  ECC */
1195         for (i = 0; i < eccfrag_len ; i += chip->ecc.bytes, p += chip->ecc.size)
1196                 chip->ecc.calculate(mtd, p, &chip->buffers->ecccalc[i]);
1197
1198         /* The performance is faster if to position offsets
1199            according to ecc.pos. Let make sure here that
1200            there are no gaps in ecc positions */
1201         for (i = 0; i < eccfrag_len - 1; i++) {
1202                 if (eccpos[i + start_step * chip->ecc.bytes] + 1 !=
1203                         eccpos[i + start_step * chip->ecc.bytes + 1]) {
1204                         gaps = 1;
1205                         break;
1206                 }
1207         }
1208         if (gaps) {
1209                 chip->cmdfunc(mtd, NAND_CMD_RNDOUT, mtd->writesize, -1);
1210                 chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
1211         } else {
1212                 /* send the command to read the particular ecc bytes */
1213                 /* take care about buswidth alignment in read_buf */
1214                 index = start_step * chip->ecc.bytes;
1215
1216                 aligned_pos = eccpos[index] & ~(busw - 1);
1217                 aligned_len = eccfrag_len;
1218                 if (eccpos[index] & (busw - 1))
1219                         aligned_len++;
1220                 if (eccpos[index + (num_steps * chip->ecc.bytes)] & (busw - 1))
1221                         aligned_len++;
1222
1223                 chip->cmdfunc(mtd, NAND_CMD_RNDOUT,
1224                                         mtd->writesize + aligned_pos, -1);
1225                 chip->read_buf(mtd, &chip->oob_poi[aligned_pos], aligned_len);
1226         }
1227
1228         for (i = 0; i < eccfrag_len; i++)
1229                 chip->buffers->ecccode[i] = chip->oob_poi[eccpos[i + index]];
1230
1231         p = bufpoi + data_col_addr;
1232         for (i = 0; i < eccfrag_len ; i += chip->ecc.bytes, p += chip->ecc.size) {
1233                 int stat;
1234
1235                 stat = chip->ecc.correct(mtd, p,
1236                         &chip->buffers->ecccode[i], &chip->buffers->ecccalc[i]);
1237                 if (stat < 0)
1238                         mtd->ecc_stats.failed++;
1239                 else
1240                         mtd->ecc_stats.corrected += stat;
1241         }
1242         return 0;
1243 }
1244
1245 /**
1246  * nand_read_page_hwecc - [REPLACABLE] hardware ecc based page read function
1247  * @mtd:        mtd info structure
1248  * @chip:       nand chip info structure
1249  * @buf:        buffer to store read data
1250  * @page:       page number to read
1251  *
1252  * Not for syndrome calculating ecc controllers which need a special oob layout
1253  */
1254 static int nand_read_page_hwecc(struct mtd_info *mtd, struct nand_chip *chip,
1255                                 uint8_t *buf, int page)
1256 {
1257         int i, eccsize = chip->ecc.size;
1258         int eccbytes = chip->ecc.bytes;
1259         int eccsteps = chip->ecc.steps;
1260         uint8_t *p = buf;
1261         uint8_t *ecc_calc = chip->buffers->ecccalc;
1262         uint8_t *ecc_code = chip->buffers->ecccode;
1263         uint32_t *eccpos = chip->ecc.layout->eccpos;
1264
1265         for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
1266                 chip->ecc.hwctl(mtd, NAND_ECC_READ);
1267                 chip->read_buf(mtd, p, eccsize);
1268                 chip->ecc.calculate(mtd, p, &ecc_calc[i]);
1269         }
1270         chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
1271
1272         for (i = 0; i < chip->ecc.total; i++)
1273                 ecc_code[i] = chip->oob_poi[eccpos[i]];
1274
1275         eccsteps = chip->ecc.steps;
1276         p = buf;
1277
1278         for (i = 0 ; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
1279                 int stat;
1280
1281                 stat = chip->ecc.correct(mtd, p, &ecc_code[i], &ecc_calc[i]);
1282                 if (stat < 0)
1283                         mtd->ecc_stats.failed++;
1284                 else
1285                         mtd->ecc_stats.corrected += stat;
1286         }
1287         return 0;
1288 }
1289
1290 /**
1291  * nand_read_page_hwecc_oob_first - [REPLACABLE] hw ecc, read oob first
1292  * @mtd:        mtd info structure
1293  * @chip:       nand chip info structure
1294  * @buf:        buffer to store read data
1295  * @page:       page number to read
1296  *
1297  * Hardware ECC for large page chips, require OOB to be read first.
1298  * For this ECC mode, the write_page method is re-used from ECC_HW.
1299  * These methods read/write ECC from the OOB area, unlike the
1300  * ECC_HW_SYNDROME support with multiple ECC steps, follows the
1301  * "infix ECC" scheme and reads/writes ECC from the data area, by
1302  * overwriting the NAND manufacturer bad block markings.
1303  */
1304 static int nand_read_page_hwecc_oob_first(struct mtd_info *mtd,
1305         struct nand_chip *chip, uint8_t *buf, int page)
1306 {
1307         int i, eccsize = chip->ecc.size;
1308         int eccbytes = chip->ecc.bytes;
1309         int eccsteps = chip->ecc.steps;
1310         uint8_t *p = buf;
1311         uint8_t *ecc_code = chip->buffers->ecccode;
1312         uint32_t *eccpos = chip->ecc.layout->eccpos;
1313         uint8_t *ecc_calc = chip->buffers->ecccalc;
1314
1315         /* Read the OOB area first */
1316         chip->cmdfunc(mtd, NAND_CMD_READOOB, 0, page);
1317         chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
1318         chip->cmdfunc(mtd, NAND_CMD_READ0, 0, page);
1319
1320         for (i = 0; i < chip->ecc.total; i++)
1321                 ecc_code[i] = chip->oob_poi[eccpos[i]];
1322
1323         for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
1324                 int stat;
1325
1326                 chip->ecc.hwctl(mtd, NAND_ECC_READ);
1327                 chip->read_buf(mtd, p, eccsize);
1328                 chip->ecc.calculate(mtd, p, &ecc_calc[i]);
1329
1330                 stat = chip->ecc.correct(mtd, p, &ecc_code[i], NULL);
1331                 if (stat < 0)
1332                         mtd->ecc_stats.failed++;
1333                 else
1334                         mtd->ecc_stats.corrected += stat;
1335         }
1336         return 0;
1337 }
1338
1339 /**
1340  * nand_read_page_syndrome - [REPLACABLE] hardware ecc syndrom based page read
1341  * @mtd:        mtd info structure
1342  * @chip:       nand chip info structure
1343  * @buf:        buffer to store read data
1344  * @page:       page number to read
1345  *
1346  * The hw generator calculates the error syndrome automatically. Therefor
1347  * we need a special oob layout and handling.
1348  */
1349 static int nand_read_page_syndrome(struct mtd_info *mtd, struct nand_chip *chip,
1350                                    uint8_t *buf, int page)
1351 {
1352         int i, eccsize = chip->ecc.size;
1353         int eccbytes = chip->ecc.bytes;
1354         int eccsteps = chip->ecc.steps;
1355         uint8_t *p = buf;
1356         uint8_t *oob = chip->oob_poi;
1357
1358         for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
1359                 int stat;
1360
1361                 chip->ecc.hwctl(mtd, NAND_ECC_READ);
1362                 chip->read_buf(mtd, p, eccsize);
1363
1364                 if (chip->ecc.prepad) {
1365                         chip->read_buf(mtd, oob, chip->ecc.prepad);
1366                         oob += chip->ecc.prepad;
1367                 }
1368
1369                 chip->ecc.hwctl(mtd, NAND_ECC_READSYN);
1370                 chip->read_buf(mtd, oob, eccbytes);
1371                 stat = chip->ecc.correct(mtd, p, oob, NULL);
1372
1373                 if (stat < 0)
1374                         mtd->ecc_stats.failed++;
1375                 else
1376                         mtd->ecc_stats.corrected += stat;
1377
1378                 oob += eccbytes;
1379
1380                 if (chip->ecc.postpad) {
1381                         chip->read_buf(mtd, oob, chip->ecc.postpad);
1382                         oob += chip->ecc.postpad;
1383                 }
1384         }
1385
1386         /* Calculate remaining oob bytes */
1387         i = mtd->oobsize - (oob - chip->oob_poi);
1388         if (i)
1389                 chip->read_buf(mtd, oob, i);
1390
1391         return 0;
1392 }
1393
1394 /**
1395  * nand_transfer_oob - [Internal] Transfer oob to client buffer
1396  * @chip:       nand chip structure
1397  * @oob:        oob destination address
1398  * @ops:        oob ops structure
1399  * @len:        size of oob to transfer
1400  */
1401 static uint8_t *nand_transfer_oob(struct nand_chip *chip, uint8_t *oob,
1402                                   struct mtd_oob_ops *ops, size_t len)
1403 {
1404         switch (ops->mode) {
1405
1406         case MTD_OOB_PLACE:
1407         case MTD_OOB_RAW:
1408                 memcpy(oob, chip->oob_poi + ops->ooboffs, len);
1409                 return oob + len;
1410
1411         case MTD_OOB_AUTO: {
1412                 struct nand_oobfree *free = chip->ecc.layout->oobfree;
1413                 uint32_t boffs = 0, roffs = ops->ooboffs;
1414                 size_t bytes = 0;
1415
1416                 for (; free->length && len; free++, len -= bytes) {
1417                         /* Read request not from offset 0 ? */
1418                         if (unlikely(roffs)) {
1419                                 if (roffs >= free->length) {
1420                                         roffs -= free->length;
1421                                         continue;
1422                                 }
1423                                 boffs = free->offset + roffs;
1424                                 bytes = min_t(size_t, len,
1425                                               (free->length - roffs));
1426                                 roffs = 0;
1427                         } else {
1428                                 bytes = min_t(size_t, len, free->length);
1429                                 boffs = free->offset;
1430                         }
1431                         memcpy(oob, chip->oob_poi + boffs, bytes);
1432                         oob += bytes;
1433                 }
1434                 return oob;
1435         }
1436         default:
1437                 BUG();
1438         }
1439         return NULL;
1440 }
1441
1442 /**
1443  * nand_do_read_ops - [Internal] Read data with ECC
1444  *
1445  * @mtd:        MTD device structure
1446  * @from:       offset to read from
1447  * @ops:        oob ops structure
1448  *
1449  * Internal function. Called with chip held.
1450  */
1451 static int nand_do_read_ops(struct mtd_info *mtd, loff_t from,
1452                             struct mtd_oob_ops *ops)
1453 {
1454         int chipnr, page, realpage, col, bytes, aligned;
1455         struct nand_chip *chip = mtd->priv;
1456         struct mtd_ecc_stats stats;
1457         int blkcheck = (1 << (chip->phys_erase_shift - chip->page_shift)) - 1;
1458         int sndcmd = 1;
1459         int ret = 0;
1460         uint32_t readlen = ops->len;
1461         uint32_t oobreadlen = ops->ooblen;
1462         uint32_t max_oobsize = ops->mode == MTD_OOB_AUTO ?
1463                 mtd->oobavail : mtd->oobsize;
1464
1465         uint8_t *bufpoi, *oob, *buf;
1466
1467         stats = mtd->ecc_stats;
1468
1469         chipnr = (int)(from >> chip->chip_shift);
1470         chip->select_chip(mtd, chipnr);
1471
1472         realpage = (int)(from >> chip->page_shift);
1473         page = realpage & chip->pagemask;
1474
1475         col = (int)(from & (mtd->writesize - 1));
1476
1477         buf = ops->datbuf;
1478         oob = ops->oobbuf;
1479
1480         while (1) {
1481                 bytes = min(mtd->writesize - col, readlen);
1482                 aligned = (bytes == mtd->writesize);
1483
1484                 /* Is the current page in the buffer ? */
1485                 if (realpage != chip->pagebuf || oob) {
1486                         bufpoi = aligned ? buf : chip->buffers->databuf;
1487
1488                         if (likely(sndcmd)) {
1489                                 chip->cmdfunc(mtd, NAND_CMD_READ0, 0x00, page);
1490                                 sndcmd = 0;
1491                         }
1492
1493                         /* Now read the page into the buffer */
1494                         if (unlikely(ops->mode == MTD_OOB_RAW))
1495                                 ret = chip->ecc.read_page_raw(mtd, chip,
1496                                                               bufpoi, page);
1497                         else if (!aligned && NAND_SUBPAGE_READ(chip) && !oob)
1498                                 ret = chip->ecc.read_subpage(mtd, chip,
1499                                                         col, bytes, bufpoi);
1500                         else
1501                                 ret = chip->ecc.read_page(mtd, chip, bufpoi,
1502                                                           page);
1503                         if (ret < 0)
1504                                 break;
1505
1506                         /* Transfer not aligned data */
1507                         if (!aligned) {
1508                                 if (!NAND_SUBPAGE_READ(chip) && !oob &&
1509                                     !(mtd->ecc_stats.failed - stats.failed))
1510                                         chip->pagebuf = realpage;
1511                                 memcpy(buf, chip->buffers->databuf + col, bytes);
1512                         }
1513
1514                         buf += bytes;
1515
1516                         if (unlikely(oob)) {
1517
1518                                 int toread = min(oobreadlen, max_oobsize);
1519
1520                                 if (toread) {
1521                                         oob = nand_transfer_oob(chip,
1522                                                 oob, ops, toread);
1523                                         oobreadlen -= toread;
1524                                 }
1525                         }
1526
1527                         if (!(chip->options & NAND_NO_READRDY)) {
1528                                 /*
1529                                  * Apply delay or wait for ready/busy pin. Do
1530                                  * this before the AUTOINCR check, so no
1531                                  * problems arise if a chip which does auto
1532                                  * increment is marked as NOAUTOINCR by the
1533                                  * board driver.
1534                                  */
1535                                 if (!chip->dev_ready)
1536                                         udelay(chip->chip_delay);
1537                                 else
1538                                         nand_wait_ready(mtd);
1539                         }
1540                 } else {
1541                         memcpy(buf, chip->buffers->databuf + col, bytes);
1542                         buf += bytes;
1543                 }
1544
1545                 readlen -= bytes;
1546
1547                 if (!readlen)
1548                         break;
1549
1550                 /* For subsequent reads align to page boundary. */
1551                 col = 0;
1552                 /* Increment page address */
1553                 realpage++;
1554
1555                 page = realpage & chip->pagemask;
1556                 /* Check, if we cross a chip boundary */
1557                 if (!page) {
1558                         chipnr++;
1559                         chip->select_chip(mtd, -1);
1560                         chip->select_chip(mtd, chipnr);
1561                 }
1562
1563                 /* Check, if the chip supports auto page increment
1564                  * or if we have hit a block boundary.
1565                  */
1566                 if (!NAND_CANAUTOINCR(chip) || !(page & blkcheck))
1567                         sndcmd = 1;
1568         }
1569
1570         ops->retlen = ops->len - (size_t) readlen;
1571         if (oob)
1572                 ops->oobretlen = ops->ooblen - oobreadlen;
1573
1574         if (ret)
1575                 return ret;
1576
1577         if (mtd->ecc_stats.failed - stats.failed)
1578                 return -EBADMSG;
1579
1580         return  mtd->ecc_stats.corrected - stats.corrected ? -EUCLEAN : 0;
1581 }
1582
1583 /**
1584  * nand_read - [MTD Interface] MTD compability function for nand_do_read_ecc
1585  * @mtd:        MTD device structure
1586  * @from:       offset to read from
1587  * @len:        number of bytes to read
1588  * @retlen:     pointer to variable to store the number of read bytes
1589  * @buf:        the databuffer to put data
1590  *
1591  * Get hold of the chip and call nand_do_read
1592  */
1593 static int nand_read(struct mtd_info *mtd, loff_t from, size_t len,
1594                      size_t *retlen, uint8_t *buf)
1595 {
1596         struct nand_chip *chip = mtd->priv;
1597         int ret;
1598
1599         /* Do not allow reads past end of device */
1600         if ((from + len) > mtd->size)
1601                 return -EINVAL;
1602         if (!len)
1603                 return 0;
1604
1605         nand_get_device(chip, mtd, FL_READING);
1606
1607         chip->ops.len = len;
1608         chip->ops.datbuf = buf;
1609         chip->ops.oobbuf = NULL;
1610
1611         ret = nand_do_read_ops(mtd, from, &chip->ops);
1612
1613         *retlen = chip->ops.retlen;
1614
1615         nand_release_device(mtd);
1616
1617         return ret;
1618 }
1619
1620 /**
1621  * nand_read_oob_std - [REPLACABLE] the most common OOB data read function
1622  * @mtd:        mtd info structure
1623  * @chip:       nand chip info structure
1624  * @page:       page number to read
1625  * @sndcmd:     flag whether to issue read command or not
1626  */
1627 static int nand_read_oob_std(struct mtd_info *mtd, struct nand_chip *chip,
1628                              int page, int sndcmd)
1629 {
1630         if (sndcmd) {
1631                 chip->cmdfunc(mtd, NAND_CMD_READOOB, 0, page);
1632                 sndcmd = 0;
1633         }
1634         chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
1635         return sndcmd;
1636 }
1637
1638 /**
1639  * nand_read_oob_syndrome - [REPLACABLE] OOB data read function for HW ECC
1640  *                          with syndromes
1641  * @mtd:        mtd info structure
1642  * @chip:       nand chip info structure
1643  * @page:       page number to read
1644  * @sndcmd:     flag whether to issue read command or not
1645  */
1646 static int nand_read_oob_syndrome(struct mtd_info *mtd, struct nand_chip *chip,
1647                                   int page, int sndcmd)
1648 {
1649         uint8_t *buf = chip->oob_poi;
1650         int length = mtd->oobsize;
1651         int chunk = chip->ecc.bytes + chip->ecc.prepad + chip->ecc.postpad;
1652         int eccsize = chip->ecc.size;
1653         uint8_t *bufpoi = buf;
1654         int i, toread, sndrnd = 0, pos;
1655
1656         chip->cmdfunc(mtd, NAND_CMD_READ0, chip->ecc.size, page);
1657         for (i = 0; i < chip->ecc.steps; i++) {
1658                 if (sndrnd) {
1659                         pos = eccsize + i * (eccsize + chunk);
1660                         if (mtd->writesize > 512)
1661                                 chip->cmdfunc(mtd, NAND_CMD_RNDOUT, pos, -1);
1662                         else
1663                                 chip->cmdfunc(mtd, NAND_CMD_READ0, pos, page);
1664                 } else
1665                         sndrnd = 1;
1666                 toread = min_t(int, length, chunk);
1667                 chip->read_buf(mtd, bufpoi, toread);
1668                 bufpoi += toread;
1669                 length -= toread;
1670         }
1671         if (length > 0)
1672                 chip->read_buf(mtd, bufpoi, length);
1673
1674         return 1;
1675 }
1676
1677 /**
1678  * nand_write_oob_std - [REPLACABLE] the most common OOB data write function
1679  * @mtd:        mtd info structure
1680  * @chip:       nand chip info structure
1681  * @page:       page number to write
1682  */
1683 static int nand_write_oob_std(struct mtd_info *mtd, struct nand_chip *chip,
1684                               int page)
1685 {
1686         int status = 0;
1687         const uint8_t *buf = chip->oob_poi;
1688         int length = mtd->oobsize;
1689
1690         chip->cmdfunc(mtd, NAND_CMD_SEQIN, mtd->writesize, page);
1691         chip->write_buf(mtd, buf, length);
1692         /* Send command to program the OOB data */
1693         chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
1694
1695         status = chip->waitfunc(mtd, chip);
1696
1697         return status & NAND_STATUS_FAIL ? -EIO : 0;
1698 }
1699
1700 /**
1701  * nand_write_oob_syndrome - [REPLACABLE] OOB data write function for HW ECC
1702  *                           with syndrome - only for large page flash !
1703  * @mtd:        mtd info structure
1704  * @chip:       nand chip info structure
1705  * @page:       page number to write
1706  */
1707 static int nand_write_oob_syndrome(struct mtd_info *mtd,
1708                                    struct nand_chip *chip, int page)
1709 {
1710         int chunk = chip->ecc.bytes + chip->ecc.prepad + chip->ecc.postpad;
1711         int eccsize = chip->ecc.size, length = mtd->oobsize;
1712         int i, len, pos, status = 0, sndcmd = 0, steps = chip->ecc.steps;
1713         const uint8_t *bufpoi = chip->oob_poi;
1714
1715         /*
1716          * data-ecc-data-ecc ... ecc-oob
1717          * or
1718          * data-pad-ecc-pad-data-pad .... ecc-pad-oob
1719          */
1720         if (!chip->ecc.prepad && !chip->ecc.postpad) {
1721                 pos = steps * (eccsize + chunk);
1722                 steps = 0;
1723         } else
1724                 pos = eccsize;
1725
1726         chip->cmdfunc(mtd, NAND_CMD_SEQIN, pos, page);
1727         for (i = 0; i < steps; i++) {
1728                 if (sndcmd) {
1729                         if (mtd->writesize <= 512) {
1730                                 uint32_t fill = 0xFFFFFFFF;
1731
1732                                 len = eccsize;
1733                                 while (len > 0) {
1734                                         int num = min_t(int, len, 4);
1735                                         chip->write_buf(mtd, (uint8_t *)&fill,
1736                                                         num);
1737                                         len -= num;
1738                                 }
1739                         } else {
1740                                 pos = eccsize + i * (eccsize + chunk);
1741                                 chip->cmdfunc(mtd, NAND_CMD_RNDIN, pos, -1);
1742                         }
1743                 } else
1744                         sndcmd = 1;
1745                 len = min_t(int, length, chunk);
1746                 chip->write_buf(mtd, bufpoi, len);
1747                 bufpoi += len;
1748                 length -= len;
1749         }
1750         if (length > 0)
1751                 chip->write_buf(mtd, bufpoi, length);
1752
1753         chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
1754         status = chip->waitfunc(mtd, chip);
1755
1756         return status & NAND_STATUS_FAIL ? -EIO : 0;
1757 }
1758
1759 /**
1760  * nand_do_read_oob - [Intern] NAND read out-of-band
1761  * @mtd:        MTD device structure
1762  * @from:       offset to read from
1763  * @ops:        oob operations description structure
1764  *
1765  * NAND read out-of-band data from the spare area
1766  */
1767 static int nand_do_read_oob(struct mtd_info *mtd, loff_t from,
1768                             struct mtd_oob_ops *ops)
1769 {
1770         int page, realpage, chipnr, sndcmd = 1;
1771         struct nand_chip *chip = mtd->priv;
1772         int blkcheck = (1 << (chip->phys_erase_shift - chip->page_shift)) - 1;
1773         int readlen = ops->ooblen;
1774         int len;
1775         uint8_t *buf = ops->oobbuf;
1776
1777         DEBUG(MTD_DEBUG_LEVEL3, "%s: from = 0x%08Lx, len = %i\n",
1778                         __func__, (unsigned long long)from, readlen);
1779
1780         if (ops->mode == MTD_OOB_AUTO)
1781                 len = chip->ecc.layout->oobavail;
1782         else
1783                 len = mtd->oobsize;
1784
1785         if (unlikely(ops->ooboffs >= len)) {
1786                 DEBUG(MTD_DEBUG_LEVEL0, "%s: Attempt to start read "
1787                                         "outside oob\n", __func__);
1788                 return -EINVAL;
1789         }
1790
1791         /* Do not allow reads past end of device */
1792         if (unlikely(from >= mtd->size ||
1793                      ops->ooboffs + readlen > ((mtd->size >> chip->page_shift) -
1794                                         (from >> chip->page_shift)) * len)) {
1795                 DEBUG(MTD_DEBUG_LEVEL0, "%s: Attempt read beyond end "
1796                                         "of device\n", __func__);
1797                 return -EINVAL;
1798         }
1799
1800         chipnr = (int)(from >> chip->chip_shift);
1801         chip->select_chip(mtd, chipnr);
1802
1803         /* Shift to get page */
1804         realpage = (int)(from >> chip->page_shift);
1805         page = realpage & chip->pagemask;
1806
1807         while (1) {
1808                 sndcmd = chip->ecc.read_oob(mtd, chip, page, sndcmd);
1809
1810                 len = min(len, readlen);
1811                 buf = nand_transfer_oob(chip, buf, ops, len);
1812
1813                 if (!(chip->options & NAND_NO_READRDY)) {
1814                         /*
1815                          * Apply delay or wait for ready/busy pin. Do this
1816                          * before the AUTOINCR check, so no problems arise if a
1817                          * chip which does auto increment is marked as
1818                          * NOAUTOINCR by the board driver.
1819                          */
1820                         if (!chip->dev_ready)
1821                                 udelay(chip->chip_delay);
1822                         else
1823                                 nand_wait_ready(mtd);
1824                 }
1825
1826                 readlen -= len;
1827                 if (!readlen)
1828                         break;
1829
1830                 /* Increment page address */
1831                 realpage++;
1832
1833                 page = realpage & chip->pagemask;
1834                 /* Check, if we cross a chip boundary */
1835                 if (!page) {
1836                         chipnr++;
1837                         chip->select_chip(mtd, -1);
1838                         chip->select_chip(mtd, chipnr);
1839                 }
1840
1841                 /* Check, if the chip supports auto page increment
1842                  * or if we have hit a block boundary.
1843                  */
1844                 if (!NAND_CANAUTOINCR(chip) || !(page & blkcheck))
1845                         sndcmd = 1;
1846         }
1847
1848         ops->oobretlen = ops->ooblen;
1849         return 0;
1850 }
1851
1852 /**
1853  * nand_read_oob - [MTD Interface] NAND read data and/or out-of-band
1854  * @mtd:        MTD device structure
1855  * @from:       offset to read from
1856  * @ops:        oob operation description structure
1857  *
1858  * NAND read data and/or out-of-band data
1859  */
1860 static int nand_read_oob(struct mtd_info *mtd, loff_t from,
1861                          struct mtd_oob_ops *ops)
1862 {
1863         struct nand_chip *chip = mtd->priv;
1864         int ret = -ENOTSUPP;
1865
1866         ops->retlen = 0;
1867
1868         /* Do not allow reads past end of device */
1869         if (ops->datbuf && (from + ops->len) > mtd->size) {
1870                 DEBUG(MTD_DEBUG_LEVEL0, "%s: Attempt read "
1871                                 "beyond end of device\n", __func__);
1872                 return -EINVAL;
1873         }
1874
1875         nand_get_device(chip, mtd, FL_READING);
1876
1877         switch (ops->mode) {
1878         case MTD_OOB_PLACE:
1879         case MTD_OOB_AUTO:
1880         case MTD_OOB_RAW:
1881                 break;
1882
1883         default:
1884                 goto out;
1885         }
1886
1887         if (!ops->datbuf)
1888                 ret = nand_do_read_oob(mtd, from, ops);
1889         else
1890                 ret = nand_do_read_ops(mtd, from, ops);
1891
1892 out:
1893         nand_release_device(mtd);
1894         return ret;
1895 }
1896
1897
1898 /**
1899  * nand_write_page_raw - [Intern] raw page write function
1900  * @mtd:        mtd info structure
1901  * @chip:       nand chip info structure
1902  * @buf:        data buffer
1903  *
1904  * Not for syndrome calculating ecc controllers, which use a special oob layout
1905  */
1906 static void nand_write_page_raw(struct mtd_info *mtd, struct nand_chip *chip,
1907                                 const uint8_t *buf)
1908 {
1909         chip->write_buf(mtd, buf, mtd->writesize);
1910         chip->write_buf(mtd, chip->oob_poi, mtd->oobsize);
1911 }
1912
1913 /**
1914  * nand_write_page_raw_syndrome - [Intern] raw page write function
1915  * @mtd:        mtd info structure
1916  * @chip:       nand chip info structure
1917  * @buf:        data buffer
1918  *
1919  * We need a special oob layout and handling even when ECC isn't checked.
1920  */
1921 static void nand_write_page_raw_syndrome(struct mtd_info *mtd,
1922                                         struct nand_chip *chip,
1923                                         const uint8_t *buf)
1924 {
1925         int eccsize = chip->ecc.size;
1926         int eccbytes = chip->ecc.bytes;
1927         uint8_t *oob = chip->oob_poi;
1928         int steps, size;
1929
1930         for (steps = chip->ecc.steps; steps > 0; steps--) {
1931                 chip->write_buf(mtd, buf, eccsize);
1932                 buf += eccsize;
1933
1934                 if (chip->ecc.prepad) {
1935                         chip->write_buf(mtd, oob, chip->ecc.prepad);
1936                         oob += chip->ecc.prepad;
1937                 }
1938
1939                 chip->read_buf(mtd, oob, eccbytes);
1940                 oob += eccbytes;
1941
1942                 if (chip->ecc.postpad) {
1943                         chip->write_buf(mtd, oob, chip->ecc.postpad);
1944                         oob += chip->ecc.postpad;
1945                 }
1946         }
1947
1948         size = mtd->oobsize - (oob - chip->oob_poi);
1949         if (size)
1950                 chip->write_buf(mtd, oob, size);
1951 }
1952 /**
1953  * nand_write_page_swecc - [REPLACABLE] software ecc based page write function
1954  * @mtd:        mtd info structure
1955  * @chip:       nand chip info structure
1956  * @buf:        data buffer
1957  */
1958 static void nand_write_page_swecc(struct mtd_info *mtd, struct nand_chip *chip,
1959                                   const uint8_t *buf)
1960 {
1961         int i, eccsize = chip->ecc.size;
1962         int eccbytes = chip->ecc.bytes;
1963         int eccsteps = chip->ecc.steps;
1964         uint8_t *ecc_calc = chip->buffers->ecccalc;
1965         const uint8_t *p = buf;
1966         uint32_t *eccpos = chip->ecc.layout->eccpos;
1967
1968         /* Software ecc calculation */
1969         for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize)
1970                 chip->ecc.calculate(mtd, p, &ecc_calc[i]);
1971
1972         for (i = 0; i < chip->ecc.total; i++)
1973                 chip->oob_poi[eccpos[i]] = ecc_calc[i];
1974
1975         chip->ecc.write_page_raw(mtd, chip, buf);
1976 }
1977
1978 /**
1979  * nand_write_page_hwecc - [REPLACABLE] hardware ecc based page write function
1980  * @mtd:        mtd info structure
1981  * @chip:       nand chip info structure
1982  * @buf:        data buffer
1983  */
1984 static void nand_write_page_hwecc(struct mtd_info *mtd, struct nand_chip *chip,
1985                                   const uint8_t *buf)
1986 {
1987         int i, eccsize = chip->ecc.size;
1988         int eccbytes = chip->ecc.bytes;
1989         int eccsteps = chip->ecc.steps;
1990         uint8_t *ecc_calc = chip->buffers->ecccalc;
1991         const uint8_t *p = buf;
1992         uint32_t *eccpos = chip->ecc.layout->eccpos;
1993
1994         for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
1995                 chip->ecc.hwctl(mtd, NAND_ECC_WRITE);
1996                 chip->write_buf(mtd, p, eccsize);
1997                 chip->ecc.calculate(mtd, p, &ecc_calc[i]);
1998         }
1999
2000         for (i = 0; i < chip->ecc.total; i++)
2001                 chip->oob_poi[eccpos[i]] = ecc_calc[i];
2002
2003         chip->write_buf(mtd, chip->oob_poi, mtd->oobsize);
2004 }
2005
2006 /**
2007  * nand_write_page_syndrome - [REPLACABLE] hardware ecc syndrom based page write
2008  * @mtd:        mtd info structure
2009  * @chip:       nand chip info structure
2010  * @buf:        data buffer
2011  *
2012  * The hw generator calculates the error syndrome automatically. Therefor
2013  * we need a special oob layout and handling.
2014  */
2015 static void nand_write_page_syndrome(struct mtd_info *mtd,
2016                                     struct nand_chip *chip, const uint8_t *buf)
2017 {
2018         int i, eccsize = chip->ecc.size;
2019         int eccbytes = chip->ecc.bytes;
2020         int eccsteps = chip->ecc.steps;
2021         const uint8_t *p = buf;
2022         uint8_t *oob = chip->oob_poi;
2023
2024         for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
2025
2026                 chip->ecc.hwctl(mtd, NAND_ECC_WRITE);
2027                 chip->write_buf(mtd, p, eccsize);
2028
2029                 if (chip->ecc.prepad) {
2030                         chip->write_buf(mtd, oob, chip->ecc.prepad);
2031                         oob += chip->ecc.prepad;
2032                 }
2033
2034                 chip->ecc.calculate(mtd, p, oob);
2035                 chip->write_buf(mtd, oob, eccbytes);
2036                 oob += eccbytes;
2037
2038                 if (chip->ecc.postpad) {
2039                         chip->write_buf(mtd, oob, chip->ecc.postpad);
2040                         oob += chip->ecc.postpad;
2041                 }
2042         }
2043
2044         /* Calculate remaining oob bytes */
2045         i = mtd->oobsize - (oob - chip->oob_poi);
2046         if (i)
2047                 chip->write_buf(mtd, oob, i);
2048 }
2049
2050 /**
2051  * nand_write_page - [REPLACEABLE] write one page
2052  * @mtd:        MTD device structure
2053  * @chip:       NAND chip descriptor
2054  * @buf:        the data to write
2055  * @page:       page number to write
2056  * @cached:     cached programming
2057  * @raw:        use _raw version of write_page
2058  */
2059 static int nand_write_page(struct mtd_info *mtd, struct nand_chip *chip,
2060                            const uint8_t *buf, int page, int cached, int raw)
2061 {
2062         int status;
2063
2064         chip->cmdfunc(mtd, NAND_CMD_SEQIN, 0x00, page);
2065
2066         if (unlikely(raw))
2067                 chip->ecc.write_page_raw(mtd, chip, buf);
2068         else
2069                 chip->ecc.write_page(mtd, chip, buf);
2070
2071         /*
2072          * Cached progamming disabled for now, Not sure if its worth the
2073          * trouble. The speed gain is not very impressive. (2.3->2.6Mib/s)
2074          */
2075         cached = 0;
2076
2077         if (!cached || !(chip->options & NAND_CACHEPRG)) {
2078
2079                 chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
2080                 status = chip->waitfunc(mtd, chip);
2081                 /*
2082                  * See if operation failed and additional status checks are
2083                  * available
2084                  */
2085                 if ((status & NAND_STATUS_FAIL) && (chip->errstat))
2086                         status = chip->errstat(mtd, chip, FL_WRITING, status,
2087                                                page);
2088
2089                 if (status & NAND_STATUS_FAIL)
2090                         return -EIO;
2091         } else {
2092                 chip->cmdfunc(mtd, NAND_CMD_CACHEDPROG, -1, -1);
2093                 status = chip->waitfunc(mtd, chip);
2094         }
2095
2096 #ifdef CONFIG_MTD_NAND_VERIFY_WRITE
2097         /* Send command to read back the data */
2098         chip->cmdfunc(mtd, NAND_CMD_READ0, 0, page);
2099
2100         if (chip->verify_buf(mtd, buf, mtd->writesize))
2101                 return -EIO;
2102 #endif
2103         return 0;
2104 }
2105
2106 /**
2107  * nand_fill_oob - [Internal] Transfer client buffer to oob
2108  * @chip:       nand chip structure
2109  * @oob:        oob data buffer
2110  * @len:        oob data write length
2111  * @ops:        oob ops structure
2112  */
2113 static uint8_t *nand_fill_oob(struct nand_chip *chip, uint8_t *oob, size_t len,
2114                                                 struct mtd_oob_ops *ops)
2115 {
2116         switch (ops->mode) {
2117
2118         case MTD_OOB_PLACE:
2119         case MTD_OOB_RAW:
2120                 memcpy(chip->oob_poi + ops->ooboffs, oob, len);
2121                 return oob + len;
2122
2123         case MTD_OOB_AUTO: {
2124                 struct nand_oobfree *free = chip->ecc.layout->oobfree;
2125                 uint32_t boffs = 0, woffs = ops->ooboffs;
2126                 size_t bytes = 0;
2127
2128                 for (; free->length && len; free++, len -= bytes) {
2129                         /* Write request not from offset 0 ? */
2130                         if (unlikely(woffs)) {
2131                                 if (woffs >= free->length) {
2132                                         woffs -= free->length;
2133                                         continue;
2134                                 }
2135                                 boffs = free->offset + woffs;
2136                                 bytes = min_t(size_t, len,
2137                                               (free->length - woffs));
2138                                 woffs = 0;
2139                         } else {
2140                                 bytes = min_t(size_t, len, free->length);
2141                                 boffs = free->offset;
2142                         }
2143                         memcpy(chip->oob_poi + boffs, oob, bytes);
2144                         oob += bytes;
2145                 }
2146                 return oob;
2147         }
2148         default:
2149                 BUG();
2150         }
2151         return NULL;
2152 }
2153
2154 #define NOTALIGNED(x)   ((x & (chip->subpagesize - 1)) != 0)
2155
2156 /**
2157  * nand_do_write_ops - [Internal] NAND write with ECC
2158  * @mtd:        MTD device structure
2159  * @to:         offset to write to
2160  * @ops:        oob operations description structure
2161  *
2162  * NAND write with ECC
2163  */
2164 static int nand_do_write_ops(struct mtd_info *mtd, loff_t to,
2165                              struct mtd_oob_ops *ops)
2166 {
2167         int chipnr, realpage, page, blockmask, column;
2168         struct nand_chip *chip = mtd->priv;
2169         uint32_t writelen = ops->len;
2170
2171         uint32_t oobwritelen = ops->ooblen;
2172         uint32_t oobmaxlen = ops->mode == MTD_OOB_AUTO ?
2173                                 mtd->oobavail : mtd->oobsize;
2174
2175         uint8_t *oob = ops->oobbuf;
2176         uint8_t *buf = ops->datbuf;
2177         int ret, subpage;
2178
2179         ops->retlen = 0;
2180         if (!writelen)
2181                 return 0;
2182
2183         /* reject writes, which are not page aligned */
2184         if (NOTALIGNED(to) || NOTALIGNED(ops->len)) {
2185                 printk(KERN_NOTICE "%s: Attempt to write not "
2186                                 "page aligned data\n", __func__);
2187                 return -EINVAL;
2188         }
2189
2190         column = to & (mtd->writesize - 1);
2191         subpage = column || (writelen & (mtd->writesize - 1));
2192
2193         if (subpage && oob)
2194                 return -EINVAL;
2195
2196         chipnr = (int)(to >> chip->chip_shift);
2197         chip->select_chip(mtd, chipnr);
2198
2199         /* Check, if it is write protected */
2200         if (nand_check_wp(mtd))
2201                 return -EIO;
2202
2203         realpage = (int)(to >> chip->page_shift);
2204         page = realpage & chip->pagemask;
2205         blockmask = (1 << (chip->phys_erase_shift - chip->page_shift)) - 1;
2206
2207         /* Invalidate the page cache, when we write to the cached page */
2208         if (to <= (chip->pagebuf << chip->page_shift) &&
2209             (chip->pagebuf << chip->page_shift) < (to + ops->len))
2210                 chip->pagebuf = -1;
2211
2212         /* If we're not given explicit OOB data, let it be 0xFF */
2213         if (likely(!oob))
2214                 memset(chip->oob_poi, 0xff, mtd->oobsize);
2215
2216         /* Don't allow multipage oob writes with offset */
2217         if (oob && ops->ooboffs && (ops->ooboffs + ops->ooblen > oobmaxlen))
2218                 return -EINVAL;
2219
2220         while (1) {
2221                 int bytes = mtd->writesize;
2222                 int cached = writelen > bytes && page != blockmask;
2223                 uint8_t *wbuf = buf;
2224
2225                 /* Partial page write ? */
2226                 if (unlikely(column || writelen < (mtd->writesize - 1))) {
2227                         cached = 0;
2228                         bytes = min_t(int, bytes - column, (int) writelen);
2229                         chip->pagebuf = -1;
2230                         memset(chip->buffers->databuf, 0xff, mtd->writesize);
2231                         memcpy(&chip->buffers->databuf[column], buf, bytes);
2232                         wbuf = chip->buffers->databuf;
2233                 }
2234
2235                 if (unlikely(oob)) {
2236                         size_t len = min(oobwritelen, oobmaxlen);
2237                         oob = nand_fill_oob(chip, oob, len, ops);
2238                         oobwritelen -= len;
2239                 }
2240
2241                 ret = chip->write_page(mtd, chip, wbuf, page, cached,
2242                                        (ops->mode == MTD_OOB_RAW));
2243                 if (ret)
2244                         break;
2245
2246                 writelen -= bytes;
2247                 if (!writelen)
2248                         break;
2249
2250                 column = 0;
2251                 buf += bytes;
2252                 realpage++;
2253
2254                 page = realpage & chip->pagemask;
2255                 /* Check, if we cross a chip boundary */
2256                 if (!page) {
2257                         chipnr++;
2258                         chip->select_chip(mtd, -1);
2259                         chip->select_chip(mtd, chipnr);
2260                 }
2261         }
2262
2263         ops->retlen = ops->len - writelen;
2264         if (unlikely(oob))
2265                 ops->oobretlen = ops->ooblen;
2266         return ret;
2267 }
2268
2269 /**
2270  * panic_nand_write - [MTD Interface] NAND write with ECC
2271  * @mtd:        MTD device structure
2272  * @to:         offset to write to
2273  * @len:        number of bytes to write
2274  * @retlen:     pointer to variable to store the number of written bytes
2275  * @buf:        the data to write
2276  *
2277  * NAND write with ECC. Used when performing writes in interrupt context, this
2278  * may for example be called by mtdoops when writing an oops while in panic.
2279  */
2280 static int panic_nand_write(struct mtd_info *mtd, loff_t to, size_t len,
2281                             size_t *retlen, const uint8_t *buf)
2282 {
2283         struct nand_chip *chip = mtd->priv;
2284         int ret;
2285
2286         /* Do not allow reads past end of device */
2287         if ((to + len) > mtd->size)
2288                 return -EINVAL;
2289         if (!len)
2290                 return 0;
2291
2292         /* Wait for the device to get ready.  */
2293         panic_nand_wait(mtd, chip, 400);
2294
2295         /* Grab the device.  */
2296         panic_nand_get_device(chip, mtd, FL_WRITING);
2297
2298         chip->ops.len = len;
2299         chip->ops.datbuf = (uint8_t *)buf;
2300         chip->ops.oobbuf = NULL;
2301
2302         ret = nand_do_write_ops(mtd, to, &chip->ops);
2303
2304         *retlen = chip->ops.retlen;
2305         return ret;
2306 }
2307
2308 /**
2309  * nand_write - [MTD Interface] NAND write with ECC
2310  * @mtd:        MTD device structure
2311  * @to:         offset to write to
2312  * @len:        number of bytes to write
2313  * @retlen:     pointer to variable to store the number of written bytes
2314  * @buf:        the data to write
2315  *
2316  * NAND write with ECC
2317  */
2318 static int nand_write(struct mtd_info *mtd, loff_t to, size_t len,
2319                           size_t *retlen, const uint8_t *buf)
2320 {
2321         struct nand_chip *chip = mtd->priv;
2322         int ret;
2323
2324         /* Do not allow reads past end of device */
2325         if ((to + len) > mtd->size)
2326                 return -EINVAL;
2327         if (!len)
2328                 return 0;
2329
2330         nand_get_device(chip, mtd, FL_WRITING);
2331
2332         chip->ops.len = len;
2333         chip->ops.datbuf = (uint8_t *)buf;
2334         chip->ops.oobbuf = NULL;
2335
2336         ret = nand_do_write_ops(mtd, to, &chip->ops);
2337
2338         *retlen = chip->ops.retlen;
2339
2340         nand_release_device(mtd);
2341
2342         return ret;
2343 }
2344
2345 /**
2346  * nand_do_write_oob - [MTD Interface] NAND write out-of-band
2347  * @mtd:        MTD device structure
2348  * @to:         offset to write to
2349  * @ops:        oob operation description structure
2350  *
2351  * NAND write out-of-band
2352  */
2353 static int nand_do_write_oob(struct mtd_info *mtd, loff_t to,
2354                              struct mtd_oob_ops *ops)
2355 {
2356         int chipnr, page, status, len;
2357         struct nand_chip *chip = mtd->priv;
2358
2359         DEBUG(MTD_DEBUG_LEVEL3, "%s: to = 0x%08x, len = %i\n",
2360                          __func__, (unsigned int)to, (int)ops->ooblen);
2361
2362         if (ops->mode == MTD_OOB_AUTO)
2363                 len = chip->ecc.layout->oobavail;
2364         else
2365                 len = mtd->oobsize;
2366
2367         /* Do not allow write past end of page */
2368         if ((ops->ooboffs + ops->ooblen) > len) {
2369                 DEBUG(MTD_DEBUG_LEVEL0, "%s: Attempt to write "
2370                                 "past end of page\n", __func__);
2371                 return -EINVAL;
2372         }
2373
2374         if (unlikely(ops->ooboffs >= len)) {
2375                 DEBUG(MTD_DEBUG_LEVEL0, "%s: Attempt to start "
2376                                 "write outside oob\n", __func__);
2377                 return -EINVAL;
2378         }
2379
2380         /* Do not allow reads past end of device */
2381         if (unlikely(to >= mtd->size ||
2382                      ops->ooboffs + ops->ooblen >
2383                         ((mtd->size >> chip->page_shift) -
2384                          (to >> chip->page_shift)) * len)) {
2385                 DEBUG(MTD_DEBUG_LEVEL0, "%s: Attempt write beyond "
2386                                 "end of device\n", __func__);
2387                 return -EINVAL;
2388         }
2389
2390         chipnr = (int)(to >> chip->chip_shift);
2391         chip->select_chip(mtd, chipnr);
2392
2393         /* Shift to get page */
2394         page = (int)(to >> chip->page_shift);
2395
2396         /*
2397          * Reset the chip. Some chips (like the Toshiba TC5832DC found in one
2398          * of my DiskOnChip 2000 test units) will clear the whole data page too
2399          * if we don't do this. I have no clue why, but I seem to have 'fixed'
2400          * it in the doc2000 driver in August 1999.  dwmw2.
2401          */
2402         chip->cmdfunc(mtd, NAND_CMD_RESET, -1, -1);
2403
2404         /* Check, if it is write protected */
2405         if (nand_check_wp(mtd))
2406                 return -EROFS;
2407
2408         /* Invalidate the page cache, if we write to the cached page */
2409         if (page == chip->pagebuf)
2410                 chip->pagebuf = -1;
2411
2412         memset(chip->oob_poi, 0xff, mtd->oobsize);
2413         nand_fill_oob(chip, ops->oobbuf, ops->ooblen, ops);
2414         status = chip->ecc.write_oob(mtd, chip, page & chip->pagemask);
2415         memset(chip->oob_poi, 0xff, mtd->oobsize);
2416
2417         if (status)
2418                 return status;
2419
2420         ops->oobretlen = ops->ooblen;
2421
2422         return 0;
2423 }
2424
2425 /**
2426  * nand_write_oob - [MTD Interface] NAND write data and/or out-of-band
2427  * @mtd:        MTD device structure
2428  * @to:         offset to write to
2429  * @ops:        oob operation description structure
2430  */
2431 static int nand_write_oob(struct mtd_info *mtd, loff_t to,
2432                           struct mtd_oob_ops *ops)
2433 {
2434         struct nand_chip *chip = mtd->priv;
2435         int ret = -ENOTSUPP;
2436
2437         ops->retlen = 0;
2438
2439         /* Do not allow writes past end of device */
2440         if (ops->datbuf && (to + ops->len) > mtd->size) {
2441                 DEBUG(MTD_DEBUG_LEVEL0, "%s: Attempt write beyond "
2442                                 "end of device\n", __func__);
2443                 return -EINVAL;
2444         }
2445
2446         nand_get_device(chip, mtd, FL_WRITING);
2447
2448         switch (ops->mode) {
2449         case MTD_OOB_PLACE:
2450         case MTD_OOB_AUTO:
2451         case MTD_OOB_RAW:
2452                 break;
2453
2454         default:
2455                 goto out;
2456         }
2457
2458         if (!ops->datbuf)
2459                 ret = nand_do_write_oob(mtd, to, ops);
2460         else
2461                 ret = nand_do_write_ops(mtd, to, ops);
2462
2463 out:
2464         nand_release_device(mtd);
2465         return ret;
2466 }
2467
2468 /**
2469  * single_erease_cmd - [GENERIC] NAND standard block erase command function
2470  * @mtd:        MTD device structure
2471  * @page:       the page address of the block which will be erased
2472  *
2473  * Standard erase command for NAND chips
2474  */
2475 static void single_erase_cmd(struct mtd_info *mtd, int page)
2476 {
2477         struct nand_chip *chip = mtd->priv;
2478         /* Send commands to erase a block */
2479         chip->cmdfunc(mtd, NAND_CMD_ERASE1, -1, page);
2480         chip->cmdfunc(mtd, NAND_CMD_ERASE2, -1, -1);
2481 }
2482
2483 /**
2484  * multi_erease_cmd - [GENERIC] AND specific block erase command function
2485  * @mtd:        MTD device structure
2486  * @page:       the page address of the block which will be erased
2487  *
2488  * AND multi block erase command function
2489  * Erase 4 consecutive blocks
2490  */
2491 static void multi_erase_cmd(struct mtd_info *mtd, int page)
2492 {
2493         struct nand_chip *chip = mtd->priv;
2494         /* Send commands to erase a block */
2495         chip->cmdfunc(mtd, NAND_CMD_ERASE1, -1, page++);
2496         chip->cmdfunc(mtd, NAND_CMD_ERASE1, -1, page++);
2497         chip->cmdfunc(mtd, NAND_CMD_ERASE1, -1, page++);
2498         chip->cmdfunc(mtd, NAND_CMD_ERASE1, -1, page);
2499         chip->cmdfunc(mtd, NAND_CMD_ERASE2, -1, -1);
2500 }
2501
2502 /**
2503  * nand_erase - [MTD Interface] erase block(s)
2504  * @mtd:        MTD device structure
2505  * @instr:      erase instruction
2506  *
2507  * Erase one ore more blocks
2508  */
2509 static int nand_erase(struct mtd_info *mtd, struct erase_info *instr)
2510 {
2511         return nand_erase_nand(mtd, instr, 0);
2512 }
2513
2514 #define BBT_PAGE_MASK   0xffffff3f
2515 /**
2516  * nand_erase_nand - [Internal] erase block(s)
2517  * @mtd:        MTD device structure
2518  * @instr:      erase instruction
2519  * @allowbbt:   allow erasing the bbt area
2520  *
2521  * Erase one ore more blocks
2522  */
2523 int nand_erase_nand(struct mtd_info *mtd, struct erase_info *instr,
2524                     int allowbbt)
2525 {
2526         int page, status, pages_per_block, ret, chipnr;
2527         struct nand_chip *chip = mtd->priv;
2528         loff_t rewrite_bbt[NAND_MAX_CHIPS] = {0};
2529         unsigned int bbt_masked_page = 0xffffffff;
2530         loff_t len;
2531
2532         DEBUG(MTD_DEBUG_LEVEL3, "%s: start = 0x%012llx, len = %llu\n",
2533                                 __func__, (unsigned long long)instr->addr,
2534                                 (unsigned long long)instr->len);
2535
2536         if (check_offs_len(mtd, instr->addr, instr->len))
2537                 return -EINVAL;
2538
2539         instr->fail_addr = MTD_FAIL_ADDR_UNKNOWN;
2540
2541         /* Grab the lock and see if the device is available */
2542         nand_get_device(chip, mtd, FL_ERASING);
2543
2544         /* Shift to get first page */
2545         page = (int)(instr->addr >> chip->page_shift);
2546         chipnr = (int)(instr->addr >> chip->chip_shift);
2547
2548         /* Calculate pages in each block */
2549         pages_per_block = 1 << (chip->phys_erase_shift - chip->page_shift);
2550
2551         /* Select the NAND device */
2552         chip->select_chip(mtd, chipnr);
2553
2554         /* Check, if it is write protected */
2555         if (nand_check_wp(mtd)) {
2556                 DEBUG(MTD_DEBUG_LEVEL0, "%s: Device is write protected!!!\n",
2557                                         __func__);
2558                 instr->state = MTD_ERASE_FAILED;
2559                 goto erase_exit;
2560         }
2561
2562         /*
2563          * If BBT requires refresh, set the BBT page mask to see if the BBT
2564          * should be rewritten. Otherwise the mask is set to 0xffffffff which
2565          * can not be matched. This is also done when the bbt is actually
2566          * erased to avoid recusrsive updates
2567          */
2568         if (chip->options & BBT_AUTO_REFRESH && !allowbbt)
2569                 bbt_masked_page = chip->bbt_td->pages[chipnr] & BBT_PAGE_MASK;
2570
2571         /* Loop through the pages */
2572         len = instr->len;
2573
2574         instr->state = MTD_ERASING;
2575
2576         while (len) {
2577                 /*
2578                  * heck if we have a bad block, we do not erase bad blocks !
2579                  */
2580                 if (nand_block_checkbad(mtd, ((loff_t) page) <<
2581                                         chip->page_shift, 0, allowbbt)) {
2582                         printk(KERN_WARNING "%s: attempt to erase a bad block "
2583                                         "at page 0x%08x\n", __func__, page);
2584                         instr->state = MTD_ERASE_FAILED;
2585                         goto erase_exit;
2586                 }
2587
2588                 /*
2589                  * Invalidate the page cache, if we erase the block which
2590                  * contains the current cached page
2591                  */
2592                 if (page <= chip->pagebuf && chip->pagebuf <
2593                     (page + pages_per_block))
2594                         chip->pagebuf = -1;
2595
2596                 chip->erase_cmd(mtd, page & chip->pagemask);
2597
2598                 status = chip->waitfunc(mtd, chip);
2599
2600                 /*
2601                  * See if operation failed and additional status checks are
2602                  * available
2603                  */
2604                 if ((status & NAND_STATUS_FAIL) && (chip->errstat))
2605                         status = chip->errstat(mtd, chip, FL_ERASING,
2606                                                status, page);
2607
2608                 /* See if block erase succeeded */
2609                 if (status & NAND_STATUS_FAIL) {
2610                         DEBUG(MTD_DEBUG_LEVEL0, "%s: Failed erase, "
2611                                         "page 0x%08x\n", __func__, page);
2612                         instr->state = MTD_ERASE_FAILED;
2613                         instr->fail_addr =
2614                                 ((loff_t)page << chip->page_shift);
2615                         goto erase_exit;
2616                 }
2617
2618                 /*
2619                  * If BBT requires refresh, set the BBT rewrite flag to the
2620                  * page being erased
2621                  */
2622                 if (bbt_masked_page != 0xffffffff &&
2623                     (page & BBT_PAGE_MASK) == bbt_masked_page)
2624                             rewrite_bbt[chipnr] =
2625                                         ((loff_t)page << chip->page_shift);
2626
2627                 /* Increment page address and decrement length */
2628                 len -= (1 << chip->phys_erase_shift);
2629                 page += pages_per_block;
2630
2631                 /* Check, if we cross a chip boundary */
2632                 if (len && !(page & chip->pagemask)) {
2633                         chipnr++;
2634                         chip->select_chip(mtd, -1);
2635                         chip->select_chip(mtd, chipnr);
2636
2637                         /*
2638                          * If BBT requires refresh and BBT-PERCHIP, set the BBT
2639                          * page mask to see if this BBT should be rewritten
2640                          */
2641                         if (bbt_masked_page != 0xffffffff &&
2642                             (chip->bbt_td->options & NAND_BBT_PERCHIP))
2643                                 bbt_masked_page = chip->bbt_td->pages[chipnr] &
2644                                         BBT_PAGE_MASK;
2645                 }
2646         }
2647         instr->state = MTD_ERASE_DONE;
2648
2649 erase_exit:
2650
2651         ret = instr->state == MTD_ERASE_DONE ? 0 : -EIO;
2652
2653         /* Deselect and wake up anyone waiting on the device */
2654         nand_release_device(mtd);
2655
2656         /* Do call back function */
2657         if (!ret)
2658                 mtd_erase_callback(instr);
2659
2660         /*
2661          * If BBT requires refresh and erase was successful, rewrite any
2662          * selected bad block tables
2663          */
2664         if (bbt_masked_page == 0xffffffff || ret)
2665                 return ret;
2666
2667         for (chipnr = 0; chipnr < chip->numchips; chipnr++) {
2668                 if (!rewrite_bbt[chipnr])
2669                         continue;
2670                 /* update the BBT for chip */
2671                 DEBUG(MTD_DEBUG_LEVEL0, "%s: nand_update_bbt "
2672                         "(%d:0x%0llx 0x%0x)\n", __func__, chipnr,
2673                         rewrite_bbt[chipnr], chip->bbt_td->pages[chipnr]);
2674                 nand_update_bbt(mtd, rewrite_bbt[chipnr]);
2675         }
2676
2677         /* Return more or less happy */
2678         return ret;
2679 }
2680
2681 /**
2682  * nand_sync - [MTD Interface] sync
2683  * @mtd:        MTD device structure
2684  *
2685  * Sync is actually a wait for chip ready function
2686  */
2687 static void nand_sync(struct mtd_info *mtd)
2688 {
2689         struct nand_chip *chip = mtd->priv;
2690
2691         DEBUG(MTD_DEBUG_LEVEL3, "%s: called\n", __func__);
2692
2693         /* Grab the lock and see if the device is available */
2694         nand_get_device(chip, mtd, FL_SYNCING);
2695         /* Release it and go back */
2696         nand_release_device(mtd);
2697 }
2698
2699 /**
2700  * nand_block_isbad - [MTD Interface] Check if block at offset is bad
2701  * @mtd:        MTD device structure
2702  * @offs:       offset relative to mtd start
2703  */
2704 static int nand_block_isbad(struct mtd_info *mtd, loff_t offs)
2705 {
2706         /* Check for invalid offset */
2707         if (offs > mtd->size)
2708                 return -EINVAL;
2709
2710         return nand_block_checkbad(mtd, offs, 1, 0);
2711 }
2712
2713 /**
2714  * nand_block_markbad - [MTD Interface] Mark block at the given offset as bad
2715  * @mtd:        MTD device structure
2716  * @ofs:        offset relative to mtd start
2717  */
2718 static int nand_block_markbad(struct mtd_info *mtd, loff_t ofs)
2719 {
2720         struct nand_chip *chip = mtd->priv;
2721         int ret;
2722
2723         ret = nand_block_isbad(mtd, ofs);
2724         if (ret) {
2725                 /* If it was bad already, return success and do nothing. */
2726                 if (ret > 0)
2727                         return 0;
2728                 return ret;
2729         }
2730
2731         return chip->block_markbad(mtd, ofs);
2732 }
2733
2734 /**
2735  * nand_suspend - [MTD Interface] Suspend the NAND flash
2736  * @mtd:        MTD device structure
2737  */
2738 static int nand_suspend(struct mtd_info *mtd)
2739 {
2740         struct nand_chip *chip = mtd->priv;
2741
2742         return nand_get_device(chip, mtd, FL_PM_SUSPENDED);
2743 }
2744
2745 /**
2746  * nand_resume - [MTD Interface] Resume the NAND flash
2747  * @mtd:        MTD device structure
2748  */
2749 static void nand_resume(struct mtd_info *mtd)
2750 {
2751         struct nand_chip *chip = mtd->priv;
2752
2753         if (chip->state == FL_PM_SUSPENDED)
2754                 nand_release_device(mtd);
2755         else
2756                 printk(KERN_ERR "%s called for a chip which is not "
2757                        "in suspended state\n", __func__);
2758 }
2759
2760 /*
2761  * Set default functions
2762  */
2763 static void nand_set_defaults(struct nand_chip *chip, int busw)
2764 {
2765         /* check for proper chip_delay setup, set 20us if not */
2766         if (!chip->chip_delay)
2767                 chip->chip_delay = 20;
2768
2769         /* check, if a user supplied command function given */
2770         if (chip->cmdfunc == NULL)
2771                 chip->cmdfunc = nand_command;
2772
2773         /* check, if a user supplied wait function given */
2774         if (chip->waitfunc == NULL)
2775                 chip->waitfunc = nand_wait;
2776
2777         if (!chip->select_chip)
2778                 chip->select_chip = nand_select_chip;
2779         if (!chip->read_byte)
2780                 chip->read_byte = busw ? nand_read_byte16 : nand_read_byte;
2781         if (!chip->read_word)
2782                 chip->read_word = nand_read_word;
2783         if (!chip->block_bad)
2784                 chip->block_bad = nand_block_bad;
2785         if (!chip->block_markbad)
2786                 chip->block_markbad = nand_default_block_markbad;
2787         if (!chip->write_buf)
2788                 chip->write_buf = busw ? nand_write_buf16 : nand_write_buf;
2789         if (!chip->read_buf)
2790                 chip->read_buf = busw ? nand_read_buf16 : nand_read_buf;
2791         if (!chip->verify_buf)
2792                 chip->verify_buf = busw ? nand_verify_buf16 : nand_verify_buf;
2793         if (!chip->scan_bbt)
2794                 chip->scan_bbt = nand_default_bbt;
2795
2796         if (!chip->controller) {
2797                 chip->controller = &chip->hwcontrol;
2798                 spin_lock_init(&chip->controller->lock);
2799                 init_waitqueue_head(&chip->controller->wq);
2800         }
2801
2802 }
2803
2804 /*
2805  * sanitize ONFI strings so we can safely print them
2806  */
2807 static void sanitize_string(uint8_t *s, size_t len)
2808 {
2809         ssize_t i;
2810
2811         /* null terminate */
2812         s[len - 1] = 0;
2813
2814         /* remove non printable chars */
2815         for (i = 0; i < len - 1; i++) {
2816                 if (s[i] < ' ' || s[i] > 127)
2817                         s[i] = '?';
2818         }
2819
2820         /* remove trailing spaces */
2821         strim(s);
2822 }
2823
2824 static u16 onfi_crc16(u16 crc, u8 const *p, size_t len)
2825 {
2826         int i;
2827         while (len--) {
2828                 crc ^= *p++ << 8;
2829                 for (i = 0; i < 8; i++)
2830                         crc = (crc << 1) ^ ((crc & 0x8000) ? 0x8005 : 0);
2831         }
2832
2833         return crc;
2834 }
2835
2836 /*
2837  * Check if the NAND chip is ONFI compliant, returns 1 if it is, 0 otherwise
2838  */
2839 static int nand_flash_detect_onfi(struct mtd_info *mtd, struct nand_chip *chip,
2840                                         int busw)
2841 {
2842         struct nand_onfi_params *p = &chip->onfi_params;
2843         int i;
2844         int val;
2845
2846         /* try ONFI for unknow chip or LP */
2847         chip->cmdfunc(mtd, NAND_CMD_READID, 0x20, -1);
2848         if (chip->read_byte(mtd) != 'O' || chip->read_byte(mtd) != 'N' ||
2849                 chip->read_byte(mtd) != 'F' || chip->read_byte(mtd) != 'I')
2850                 return 0;
2851
2852         printk(KERN_INFO "ONFI flash detected\n");
2853         chip->cmdfunc(mtd, NAND_CMD_PARAM, 0, -1);
2854         for (i = 0; i < 3; i++) {
2855                 chip->read_buf(mtd, (uint8_t *)p, sizeof(*p));
2856                 if (onfi_crc16(ONFI_CRC_BASE, (uint8_t *)p, 254) ==
2857                                 le16_to_cpu(p->crc)) {
2858                         printk(KERN_INFO "ONFI param page %d valid\n", i);
2859                         break;
2860                 }
2861         }
2862
2863         if (i == 3)
2864                 return 0;
2865
2866         /* check version */
2867         val = le16_to_cpu(p->revision);
2868         if (val == 1 || val > (1 << 4)) {
2869                 printk(KERN_INFO "%s: unsupported ONFI version: %d\n",
2870                                                                 __func__, val);
2871                 return 0;
2872         }
2873
2874         if (val & (1 << 4))
2875                 chip->onfi_version = 22;
2876         else if (val & (1 << 3))
2877                 chip->onfi_version = 21;
2878         else if (val & (1 << 2))
2879                 chip->onfi_version = 20;
2880         else
2881                 chip->onfi_version = 10;
2882
2883         sanitize_string(p->manufacturer, sizeof(p->manufacturer));
2884         sanitize_string(p->model, sizeof(p->model));
2885         if (!mtd->name)
2886                 mtd->name = p->model;
2887         mtd->writesize = le32_to_cpu(p->byte_per_page);
2888         mtd->erasesize = le32_to_cpu(p->pages_per_block) * mtd->writesize;
2889         mtd->oobsize = le16_to_cpu(p->spare_bytes_per_page);
2890         chip->chipsize = le32_to_cpu(p->blocks_per_lun) * mtd->erasesize;
2891         busw = 0;
2892         if (le16_to_cpu(p->features) & 1)
2893                 busw = NAND_BUSWIDTH_16;
2894
2895         chip->options &= ~NAND_CHIPOPTIONS_MSK;
2896         chip->options |= (NAND_NO_READRDY |
2897                         NAND_NO_AUTOINCR) & NAND_CHIPOPTIONS_MSK;
2898
2899         return 1;
2900 }
2901
2902 /*
2903  * Get the flash and manufacturer id and lookup if the type is supported
2904  */
2905 static struct nand_flash_dev *nand_get_flash_type(struct mtd_info *mtd,
2906                                                   struct nand_chip *chip,
2907                                                   int busw,
2908                                                   int *maf_id, int *dev_id,
2909                                                   struct nand_flash_dev *type)
2910 {
2911         int i, maf_idx;
2912         u8 id_data[8];
2913         int ret;
2914
2915         /* Select the device */
2916         chip->select_chip(mtd, 0);
2917
2918         /*
2919          * Reset the chip, required by some chips (e.g. Micron MT29FxGxxxxx)
2920          * after power-up
2921          */
2922         chip->cmdfunc(mtd, NAND_CMD_RESET, -1, -1);
2923
2924         /* Send the command for reading device ID */
2925         chip->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1);
2926
2927         /* Read manufacturer and device IDs */
2928         *maf_id = chip->read_byte(mtd);
2929         *dev_id = chip->read_byte(mtd);
2930
2931         /* Try again to make sure, as some systems the bus-hold or other
2932          * interface concerns can cause random data which looks like a
2933          * possibly credible NAND flash to appear. If the two results do
2934          * not match, ignore the device completely.
2935          */
2936
2937         chip->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1);
2938
2939         for (i = 0; i < 2; i++)
2940                 id_data[i] = chip->read_byte(mtd);
2941
2942         if (id_data[0] != *maf_id || id_data[1] != *dev_id) {
2943                 printk(KERN_INFO "%s: second ID read did not match "
2944                        "%02x,%02x against %02x,%02x\n", __func__,
2945                        *maf_id, *dev_id, id_data[0], id_data[1]);
2946                 return ERR_PTR(-ENODEV);
2947         }
2948
2949         if (!type)
2950                 type = nand_flash_ids;
2951
2952         for (; type->name != NULL; type++)
2953                 if (*dev_id == type->id)
2954                         break;
2955
2956         chip->onfi_version = 0;
2957         if (!type->name || !type->pagesize) {
2958                 /* Check is chip is ONFI compliant */
2959                 ret = nand_flash_detect_onfi(mtd, chip, busw);
2960                 if (ret)
2961                         goto ident_done;
2962         }
2963
2964         chip->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1);
2965
2966         /* Read entire ID string */
2967
2968         for (i = 0; i < 8; i++)
2969                 id_data[i] = chip->read_byte(mtd);
2970
2971         if (!type->name)
2972                 return ERR_PTR(-ENODEV);
2973
2974         if (!mtd->name)
2975                 mtd->name = type->name;
2976
2977         chip->chipsize = (uint64_t)type->chipsize << 20;
2978
2979         if (!type->pagesize && chip->init_size) {
2980                 /* set the pagesize, oobsize, erasesize by the driver*/
2981                 busw = chip->init_size(mtd, chip, id_data);
2982         } else if (!type->pagesize) {
2983                 int extid;
2984                 /* The 3rd id byte holds MLC / multichip data */
2985                 chip->cellinfo = id_data[2];
2986                 /* The 4th id byte is the important one */
2987                 extid = id_data[3];
2988
2989                 /*
2990                  * Field definitions are in the following datasheets:
2991                  * Old style (4,5 byte ID): Samsung K9GAG08U0M (p.32)
2992                  * New style   (6 byte ID): Samsung K9GBG08U0M (p.40)
2993                  *
2994                  * Check for wraparound + Samsung ID + nonzero 6th byte
2995                  * to decide what to do.
2996                  */
2997                 if (id_data[0] == id_data[6] && id_data[1] == id_data[7] &&
2998                                 id_data[0] == NAND_MFR_SAMSUNG &&
2999                                 (chip->cellinfo & NAND_CI_CELLTYPE_MSK) &&
3000                                 id_data[5] != 0x00) {
3001                         /* Calc pagesize */
3002                         mtd->writesize = 2048 << (extid & 0x03);
3003                         extid >>= 2;
3004                         /* Calc oobsize */
3005                         switch (extid & 0x03) {
3006                         case 1:
3007                                 mtd->oobsize = 128;
3008                                 break;
3009                         case 2:
3010                                 mtd->oobsize = 218;
3011                                 break;
3012                         case 3:
3013                                 mtd->oobsize = 400;
3014                                 break;
3015                         default:
3016                                 mtd->oobsize = 436;
3017                                 break;
3018                         }
3019                         extid >>= 2;
3020                         /* Calc blocksize */
3021                         mtd->erasesize = (128 * 1024) <<
3022                                 (((extid >> 1) & 0x04) | (extid & 0x03));
3023                         busw = 0;
3024                 } else {
3025                         /* Calc pagesize */
3026                         mtd->writesize = 1024 << (extid & 0x03);
3027                         extid >>= 2;
3028                         /* Calc oobsize */
3029                         mtd->oobsize = (8 << (extid & 0x01)) *
3030                                 (mtd->writesize >> 9);
3031                         extid >>= 2;
3032                         /* Calc blocksize. Blocksize is multiples of 64KiB */
3033                         mtd->erasesize = (64 * 1024) << (extid & 0x03);
3034                         extid >>= 2;
3035                         /* Get buswidth information */
3036                         busw = (extid & 0x01) ? NAND_BUSWIDTH_16 : 0;
3037                 }
3038         } else {
3039                 /*
3040                  * Old devices have chip data hardcoded in the device id table
3041                  */
3042                 mtd->erasesize = type->erasesize;
3043                 mtd->writesize = type->pagesize;
3044                 mtd->oobsize = mtd->writesize / 32;
3045                 busw = type->options & NAND_BUSWIDTH_16;
3046
3047                 /*
3048                  * Check for Spansion/AMD ID + repeating 5th, 6th byte since
3049                  * some Spansion chips have erasesize that conflicts with size
3050                  * listed in nand_ids table
3051                  * Data sheet (5 byte ID): Spansion S30ML-P ORNAND (p.39)
3052                  */
3053                 if (*maf_id == NAND_MFR_AMD && id_data[4] != 0x00 &&
3054                                 id_data[5] == 0x00 && id_data[6] == 0x00 &&
3055                                 id_data[7] == 0x00 && mtd->writesize == 512) {
3056                         mtd->erasesize = 128 * 1024;
3057                         mtd->erasesize <<= ((id_data[3] & 0x03) << 1);
3058                 }
3059         }
3060         /* Get chip options, preserve non chip based options */
3061         chip->options &= ~NAND_CHIPOPTIONS_MSK;
3062         chip->options |= type->options & NAND_CHIPOPTIONS_MSK;
3063
3064         /* Check if chip is a not a samsung device. Do not clear the
3065          * options for chips which are not having an extended id.
3066          */
3067         if (*maf_id != NAND_MFR_SAMSUNG && !type->pagesize)
3068                 chip->options &= ~NAND_SAMSUNG_LP_OPTIONS;
3069 ident_done:
3070
3071         /*
3072          * Set chip as a default. Board drivers can override it, if necessary
3073          */
3074         chip->options |= NAND_NO_AUTOINCR;
3075
3076         /* Try to identify manufacturer */
3077         for (maf_idx = 0; nand_manuf_ids[maf_idx].id != 0x0; maf_idx++) {
3078                 if (nand_manuf_ids[maf_idx].id == *maf_id)
3079                         break;
3080         }
3081
3082         /*
3083          * Check, if buswidth is correct. Hardware drivers should set
3084          * chip correct !
3085          */
3086         if (busw != (chip->options & NAND_BUSWIDTH_16)) {
3087                 printk(KERN_INFO "NAND device: Manufacturer ID:"
3088                        " 0x%02x, Chip ID: 0x%02x (%s %s)\n", *maf_id,
3089                        *dev_id, nand_manuf_ids[maf_idx].name, mtd->name);
3090                 printk(KERN_WARNING "NAND bus width %d instead %d bit\n",
3091                        (chip->options & NAND_BUSWIDTH_16) ? 16 : 8,
3092                        busw ? 16 : 8);
3093                 return ERR_PTR(-EINVAL);
3094         }
3095
3096         /* Calculate the address shift from the page size */
3097         chip->page_shift = ffs(mtd->writesize) - 1;
3098         /* Convert chipsize to number of pages per chip -1. */
3099         chip->pagemask = (chip->chipsize >> chip->page_shift) - 1;
3100
3101         chip->bbt_erase_shift = chip->phys_erase_shift =
3102                 ffs(mtd->erasesize) - 1;
3103         if (chip->chipsize & 0xffffffff)
3104                 chip->chip_shift = ffs((unsigned)chip->chipsize) - 1;
3105         else {
3106                 chip->chip_shift = ffs((unsigned)(chip->chipsize >> 32));
3107                 chip->chip_shift += 32 - 1;
3108         }
3109
3110         /* Set the bad block position */
3111         if (mtd->writesize > 512 || (busw & NAND_BUSWIDTH_16))
3112                 chip->badblockpos = NAND_LARGE_BADBLOCK_POS;
3113         else
3114                 chip->badblockpos = NAND_SMALL_BADBLOCK_POS;
3115
3116         /*
3117          * Bad block marker is stored in the last page of each block
3118          * on Samsung and Hynix MLC devices; stored in first two pages
3119          * of each block on Micron devices with 2KiB pages and on
3120          * SLC Samsung, Hynix, Toshiba and AMD/Spansion. All others scan
3121          * only the first page.
3122          */
3123         if ((chip->cellinfo & NAND_CI_CELLTYPE_MSK) &&
3124                         (*maf_id == NAND_MFR_SAMSUNG ||
3125                          *maf_id == NAND_MFR_HYNIX))
3126                 chip->options |= NAND_BBT_SCANLASTPAGE;
3127         else if ((!(chip->cellinfo & NAND_CI_CELLTYPE_MSK) &&
3128                                 (*maf_id == NAND_MFR_SAMSUNG ||
3129                                  *maf_id == NAND_MFR_HYNIX ||
3130                                  *maf_id == NAND_MFR_TOSHIBA ||
3131                                  *maf_id == NAND_MFR_AMD)) ||
3132                         (mtd->writesize == 2048 &&
3133                          *maf_id == NAND_MFR_MICRON))
3134                 chip->options |= NAND_BBT_SCAN2NDPAGE;
3135
3136         /*
3137          * Numonyx/ST 2K pages, x8 bus use BOTH byte 1 and 6
3138          */
3139         if (!(busw & NAND_BUSWIDTH_16) &&
3140                         *maf_id == NAND_MFR_STMICRO &&
3141                         mtd->writesize == 2048) {
3142                 chip->options |= NAND_BBT_SCANBYTE1AND6;
3143                 chip->badblockpos = 0;
3144         }
3145
3146         /* Check for AND chips with 4 page planes */
3147         if (chip->options & NAND_4PAGE_ARRAY)
3148                 chip->erase_cmd = multi_erase_cmd;
3149         else
3150                 chip->erase_cmd = single_erase_cmd;
3151
3152         /* Do not replace user supplied command function ! */
3153         if (mtd->writesize > 512 && chip->cmdfunc == nand_command)
3154                 chip->cmdfunc = nand_command_lp;
3155
3156         /* TODO onfi flash name */
3157         printk(KERN_INFO "NAND device: Manufacturer ID:"
3158                 " 0x%02x, Chip ID: 0x%02x (%s %s)\n", *maf_id, *dev_id,
3159                 nand_manuf_ids[maf_idx].name,
3160         chip->onfi_version ? type->name : chip->onfi_params.model);
3161
3162         return type;
3163 }
3164
3165 /**
3166  * nand_scan_ident - [NAND Interface] Scan for the NAND device
3167  * @mtd:             MTD device structure
3168  * @maxchips:        Number of chips to scan for
3169  * @table:           Alternative NAND ID table
3170  *
3171  * This is the first phase of the normal nand_scan() function. It
3172  * reads the flash ID and sets up MTD fields accordingly.
3173  *
3174  * The mtd->owner field must be set to the module of the caller.
3175  */
3176 int nand_scan_ident(struct mtd_info *mtd, int maxchips,
3177                     struct nand_flash_dev *table)
3178 {
3179         int i, busw, nand_maf_id, nand_dev_id;
3180         struct nand_chip *chip = mtd->priv;
3181         struct nand_flash_dev *type;
3182
3183         /* Get buswidth to select the correct functions */
3184         busw = chip->options & NAND_BUSWIDTH_16;
3185         /* Set the default functions */
3186         nand_set_defaults(chip, busw);
3187
3188         /* Read the flash type */
3189         type = nand_get_flash_type(mtd, chip, busw,
3190                                 &nand_maf_id, &nand_dev_id, table);
3191
3192         if (IS_ERR(type)) {
3193                 if (!(chip->options & NAND_SCAN_SILENT_NODEV))
3194                         printk(KERN_WARNING "No NAND device found.\n");
3195                 chip->select_chip(mtd, -1);
3196                 return PTR_ERR(type);
3197         }
3198
3199         /* Check for a chip array */
3200         for (i = 1; i < maxchips; i++) {
3201                 chip->select_chip(mtd, i);
3202                 /* See comment in nand_get_flash_type for reset */
3203                 chip->cmdfunc(mtd, NAND_CMD_RESET, -1, -1);
3204                 /* Send the command for reading device ID */
3205                 chip->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1);
3206                 /* Read manufacturer and device IDs */
3207                 if (nand_maf_id != chip->read_byte(mtd) ||
3208                     nand_dev_id != chip->read_byte(mtd))
3209                         break;
3210         }
3211         if (i > 1)
3212                 printk(KERN_INFO "%d NAND chips detected\n", i);
3213
3214         /* Store the number of chips and calc total size for mtd */
3215         chip->numchips = i;
3216         mtd->size = i * chip->chipsize;
3217
3218         return 0;
3219 }
3220 EXPORT_SYMBOL(nand_scan_ident);
3221
3222
3223 /**
3224  * nand_scan_tail - [NAND Interface] Scan for the NAND device
3225  * @mtd:            MTD device structure
3226  *
3227  * This is the second phase of the normal nand_scan() function. It
3228  * fills out all the uninitialized function pointers with the defaults
3229  * and scans for a bad block table if appropriate.
3230  */
3231 int nand_scan_tail(struct mtd_info *mtd)
3232 {
3233         int i;
3234         struct nand_chip *chip = mtd->priv;
3235
3236         if (!(chip->options & NAND_OWN_BUFFERS))
3237                 chip->buffers = kmalloc(sizeof(*chip->buffers), GFP_KERNEL);
3238         if (!chip->buffers)
3239                 return -ENOMEM;
3240
3241         /* Set the internal oob buffer location, just after the page data */
3242         chip->oob_poi = chip->buffers->databuf + mtd->writesize;
3243
3244         /*
3245          * If no default placement scheme is given, select an appropriate one
3246          */
3247         if (!chip->ecc.layout) {
3248                 switch (mtd->oobsize) {
3249                 case 8:
3250                         chip->ecc.layout = &nand_oob_8;
3251                         break;
3252                 case 16:
3253                         chip->ecc.layout = &nand_oob_16;
3254                         break;
3255                 case 64:
3256                         chip->ecc.layout = &nand_oob_64;
3257                         break;
3258                 case 128:
3259                         chip->ecc.layout = &nand_oob_128;
3260                         break;
3261                 default:
3262                         printk(KERN_WARNING "No oob scheme defined for "
3263                                "oobsize %d\n", mtd->oobsize);
3264                         BUG();
3265                 }
3266         }
3267
3268         if (!chip->write_page)
3269                 chip->write_page = nand_write_page;
3270
3271         /*
3272          * check ECC mode, default to software if 3byte/512byte hardware ECC is
3273          * selected and we have 256 byte pagesize fallback to software ECC
3274          */
3275
3276         switch (chip->ecc.mode) {
3277         case NAND_ECC_HW_OOB_FIRST:
3278                 /* Similar to NAND_ECC_HW, but a separate read_page handle */
3279                 if (!chip->ecc.calculate || !chip->ecc.correct ||
3280                      !chip->ecc.hwctl) {
3281                         printk(KERN_WARNING "No ECC functions supplied; "
3282                                "Hardware ECC not possible\n");
3283                         BUG();
3284                 }
3285                 if (!chip->ecc.read_page)
3286                         chip->ecc.read_page = nand_read_page_hwecc_oob_first;
3287
3288         case NAND_ECC_HW:
3289                 /* Use standard hwecc read page function ? */
3290                 if (!chip->ecc.read_page)
3291                         chip->ecc.read_page = nand_read_page_hwecc;
3292                 if (!chip->ecc.write_page)
3293                         chip->ecc.write_page = nand_write_page_hwecc;
3294                 if (!chip->ecc.read_page_raw)
3295                         chip->ecc.read_page_raw = nand_read_page_raw;
3296                 if (!chip->ecc.write_page_raw)
3297                         chip->ecc.write_page_raw = nand_write_page_raw;
3298                 if (!chip->ecc.read_oob)
3299                         chip->ecc.read_oob = nand_read_oob_std;
3300                 if (!chip->ecc.write_oob)
3301                         chip->ecc.write_oob = nand_write_oob_std;
3302
3303         case NAND_ECC_HW_SYNDROME:
3304                 if ((!chip->ecc.calculate || !chip->ecc.correct ||
3305                      !chip->ecc.hwctl) &&
3306                     (!chip->ecc.read_page ||
3307                      chip->ecc.read_page == nand_read_page_hwecc ||
3308                      !chip->ecc.write_page ||
3309                      chip->ecc.write_page == nand_write_page_hwecc)) {
3310                         printk(KERN_WARNING "No ECC functions supplied; "
3311                                "Hardware ECC not possible\n");
3312                         BUG();
3313                 }
3314                 /* Use standard syndrome read/write page function ? */
3315                 if (!chip->ecc.read_page)
3316                         chip->ecc.read_page = nand_read_page_syndrome;
3317                 if (!chip->ecc.write_page)
3318                         chip->ecc.write_page = nand_write_page_syndrome;
3319                 if (!chip->ecc.read_page_raw)
3320                         chip->ecc.read_page_raw = nand_read_page_raw_syndrome;
3321                 if (!chip->ecc.write_page_raw)
3322                         chip->ecc.write_page_raw = nand_write_page_raw_syndrome;
3323                 if (!chip->ecc.read_oob)
3324                         chip->ecc.read_oob = nand_read_oob_syndrome;
3325                 if (!chip->ecc.write_oob)
3326                         chip->ecc.write_oob = nand_write_oob_syndrome;
3327
3328                 if (mtd->writesize >= chip->ecc.size)
3329                         break;
3330                 printk(KERN_WARNING "%d byte HW ECC not possible on "
3331                        "%d byte page size, fallback to SW ECC\n",
3332                        chip->ecc.size, mtd->writesize);
3333                 chip->ecc.mode = NAND_ECC_SOFT;
3334
3335         case NAND_ECC_SOFT:
3336                 chip->ecc.calculate = nand_calculate_ecc;
3337                 chip->ecc.correct = nand_correct_data;
3338                 chip->ecc.read_page = nand_read_page_swecc;
3339                 chip->ecc.read_subpage = nand_read_subpage;
3340                 chip->ecc.write_page = nand_write_page_swecc;
3341                 chip->ecc.read_page_raw = nand_read_page_raw;
3342                 chip->ecc.write_page_raw = nand_write_page_raw;
3343                 chip->ecc.read_oob = nand_read_oob_std;
3344                 chip->ecc.write_oob = nand_write_oob_std;
3345                 if (!chip->ecc.size)
3346                         chip->ecc.size = 256;
3347                 chip->ecc.bytes = 3;
3348                 break;
3349
3350         case NAND_ECC_NONE:
3351                 printk(KERN_WARNING "NAND_ECC_NONE selected by board driver. "
3352                        "This is not recommended !!\n");
3353                 chip->ecc.read_page = nand_read_page_raw;
3354                 chip->ecc.write_page = nand_write_page_raw;
3355                 chip->ecc.read_oob = nand_read_oob_std;
3356                 chip->ecc.read_page_raw = nand_read_page_raw;
3357                 chip->ecc.write_page_raw = nand_write_page_raw;
3358                 chip->ecc.write_oob = nand_write_oob_std;
3359                 chip->ecc.size = mtd->writesize;
3360                 chip->ecc.bytes = 0;
3361                 break;
3362
3363         default:
3364                 printk(KERN_WARNING "Invalid NAND_ECC_MODE %d\n",
3365                        chip->ecc.mode);
3366                 BUG();
3367         }
3368
3369         /*
3370          * The number of bytes available for a client to place data into
3371          * the out of band area
3372          */
3373         chip->ecc.layout->oobavail = 0;
3374         for (i = 0; chip->ecc.layout->oobfree[i].length
3375                         && i < ARRAY_SIZE(chip->ecc.layout->oobfree); i++)
3376                 chip->ecc.layout->oobavail +=
3377                         chip->ecc.layout->oobfree[i].length;
3378         mtd->oobavail = chip->ecc.layout->oobavail;
3379
3380         /*
3381          * Set the number of read / write steps for one page depending on ECC
3382          * mode
3383          */
3384         chip->ecc.steps = mtd->writesize / chip->ecc.size;
3385         if (chip->ecc.steps * chip->ecc.size != mtd->writesize) {
3386                 printk(KERN_WARNING "Invalid ecc parameters\n");
3387                 BUG();
3388         }
3389         chip->ecc.total = chip->ecc.steps * chip->ecc.bytes;
3390
3391         /*
3392          * Allow subpage writes up to ecc.steps. Not possible for MLC
3393          * FLASH.
3394          */
3395         if (!(chip->options & NAND_NO_SUBPAGE_WRITE) &&
3396             !(chip->cellinfo & NAND_CI_CELLTYPE_MSK)) {
3397                 switch (chip->ecc.steps) {
3398                 case 2:
3399                         mtd->subpage_sft = 1;
3400                         break;
3401                 case 4:
3402                 case 8:
3403                 case 16:
3404                         mtd->subpage_sft = 2;
3405                         break;
3406                 }
3407         }
3408         chip->subpagesize = mtd->writesize >> mtd->subpage_sft;
3409
3410         /* Initialize state */
3411         chip->state = FL_READY;
3412
3413         /* De-select the device */
3414         chip->select_chip(mtd, -1);
3415
3416         /* Invalidate the pagebuffer reference */
3417         chip->pagebuf = -1;
3418
3419         /* Fill in remaining MTD driver data */
3420         mtd->type = MTD_NANDFLASH;
3421         mtd->flags = (chip->options & NAND_ROM) ? MTD_CAP_ROM :
3422                                                 MTD_CAP_NANDFLASH;
3423         mtd->erase = nand_erase;
3424         mtd->point = NULL;
3425         mtd->unpoint = NULL;
3426         mtd->read = nand_read;
3427         mtd->write = nand_write;
3428         mtd->panic_write = panic_nand_write;
3429         mtd->read_oob = nand_read_oob;
3430         mtd->write_oob = nand_write_oob;
3431         mtd->sync = nand_sync;
3432         mtd->lock = NULL;
3433         mtd->unlock = NULL;
3434         mtd->suspend = nand_suspend;
3435         mtd->resume = nand_resume;
3436         mtd->block_isbad = nand_block_isbad;
3437         mtd->block_markbad = nand_block_markbad;
3438
3439         /* propagate ecc.layout to mtd_info */
3440         mtd->ecclayout = chip->ecc.layout;
3441
3442         /* Check, if we should skip the bad block table scan */
3443         if (chip->options & NAND_SKIP_BBTSCAN)
3444                 return 0;
3445
3446         /* Build bad block table */
3447         return chip->scan_bbt(mtd);
3448 }
3449 EXPORT_SYMBOL(nand_scan_tail);
3450
3451 /* is_module_text_address() isn't exported, and it's mostly a pointless
3452  * test if this is a module _anyway_ -- they'd have to try _really_ hard
3453  * to call us from in-kernel code if the core NAND support is modular. */
3454 #ifdef MODULE
3455 #define caller_is_module() (1)
3456 #else
3457 #define caller_is_module() \
3458         is_module_text_address((unsigned long)__builtin_return_address(0))
3459 #endif
3460
3461 /**
3462  * nand_scan - [NAND Interface] Scan for the NAND device
3463  * @mtd:        MTD device structure
3464  * @maxchips:   Number of chips to scan for
3465  *
3466  * This fills out all the uninitialized function pointers
3467  * with the defaults.
3468  * The flash ID is read and the mtd/chip structures are
3469  * filled with the appropriate values.
3470  * The mtd->owner field must be set to the module of the caller
3471  *
3472  */
3473 int nand_scan(struct mtd_info *mtd, int maxchips)
3474 {
3475         int ret;
3476
3477         /* Many callers got this wrong, so check for it for a while... */
3478         if (!mtd->owner && caller_is_module()) {
3479                 printk(KERN_CRIT "%s called with NULL mtd->owner!\n",
3480                                 __func__);
3481                 BUG();
3482         }
3483
3484         ret = nand_scan_ident(mtd, maxchips, NULL);
3485         if (!ret)
3486                 ret = nand_scan_tail(mtd);
3487         return ret;
3488 }
3489 EXPORT_SYMBOL(nand_scan);
3490
3491 /**
3492  * nand_release - [NAND Interface] Free resources held by the NAND device
3493  * @mtd:        MTD device structure
3494 */
3495 void nand_release(struct mtd_info *mtd)
3496 {
3497         struct nand_chip *chip = mtd->priv;
3498
3499 #ifdef CONFIG_MTD_PARTITIONS
3500         /* Deregister partitions */
3501         del_mtd_partitions(mtd);
3502 #endif
3503         /* Deregister the device */
3504         del_mtd_device(mtd);
3505
3506         /* Free bad block table memory */
3507         kfree(chip->bbt);
3508         if (!(chip->options & NAND_OWN_BUFFERS))
3509                 kfree(chip->buffers);
3510
3511         /* Free bad block descriptor memory */
3512         if (chip->badblock_pattern && chip->badblock_pattern->options
3513                         & NAND_BBT_DYNAMICSTRUCT)
3514                 kfree(chip->badblock_pattern);
3515 }
3516 EXPORT_SYMBOL_GPL(nand_release);
3517
3518 static int __init nand_base_init(void)
3519 {
3520         led_trigger_register_simple("nand-disk", &nand_led_trigger);
3521         return 0;
3522 }
3523
3524 static void __exit nand_base_exit(void)
3525 {
3526         led_trigger_unregister_simple(nand_led_trigger);
3527 }
3528
3529 module_init(nand_base_init);
3530 module_exit(nand_base_exit);
3531
3532 MODULE_LICENSE("GPL");
3533 MODULE_AUTHOR("Steven J. Hill <sjhill@realitydiluted.com>");
3534 MODULE_AUTHOR("Thomas Gleixner <tglx@linutronix.de>");
3535 MODULE_DESCRIPTION("Generic NAND flash driver code");