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/tech/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  *
  28  * This program is free software; you can redistribute it and/or modify
  29  * it under the terms of the GNU General Public License version 2 as
  30  * published by the Free Software Foundation.
  31  *
  32  */
  33
  34 #include <linux/module.h>
  35 #include <linux/delay.h>
  36 #include <linux/errno.h>
  37 #include <linux/err.h>
  38 #include <linux/sched.h>
  39 #include <linux/slab.h>
  40 #include <linux/types.h>
  41 #include <linux/mtd/mtd.h>
  42 #include <linux/mtd/nand.h>
  43 #include <linux/mtd/nand_ecc.h>
  44 #include <linux/mtd/compatmac.h>
  45 #include <linux/interrupt.h>
  46 #include <linux/bitops.h>
  47 #include <linux/leds.h>
  48 #include <asm/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 int nand_get_device(struct nand_chip *chip, struct mtd_info *mtd,
  85                            int new_state);
  86
  87 static int nand_do_write_oob(struct mtd_info *mtd, loff_t to,
  88                              struct mtd_oob_ops *ops);
  89
  90 /*
  91  * For devices which display every fart in the system on a seperate LED. Is
  92  * compiled away when LED support is disabled.
  93  */
  94 DEFINE_LED_TRIGGER(nand_led_trigger);
  95
  96 /**
  97  * nand_release_device - [GENERIC] release chip
  98  * @mtd:        MTD device structure
  99  *
 100  * Deselect, release chip lock and wake up anyone waiting on the device
 101  */
 102 static void nand_release_device(struct mtd_info *mtd)
 103 {
 104         struct nand_chip *chip = mtd->priv;
 105
 106         /* De-select the NAND device */
 107         chip->select_chip(mtd, -1);
 108
 109         /* Release the controller and the chip */
 110         spin_lock(&chip->controller->lock);
 111         chip->controller->active = NULL;
 112         chip->state = FL_READY;
 113         wake_up(&chip->controller->wq);
 114         spin_unlock(&chip->controller->lock);
 115 }
 116
 117 /**
 118  * nand_read_byte - [DEFAULT] read one byte from the chip
 119  * @mtd:        MTD device structure
 120  *
 121  * Default read function for 8bit buswith
 122  */
 123 static uint8_t nand_read_byte(struct mtd_info *mtd)
 124 {
 125         struct nand_chip *chip = mtd->priv;
 126         return readb(chip->IO_ADDR_R);
 127 }
 128
 129 /**
 130  * nand_read_byte16 - [DEFAULT] read one byte endianess aware from the chip
 131  * @mtd:        MTD device structure
 132  *
 133  * Default read function for 16bit buswith with
 134  * endianess conversion
 135  */
 136 static uint8_t nand_read_byte16(struct mtd_info *mtd)
 137 {
 138         struct nand_chip *chip = mtd->priv;
 139         return (uint8_t) cpu_to_le16(readw(chip->IO_ADDR_R));
 140 }
 141
 142 /**
 143  * nand_read_word - [DEFAULT] read one word from the chip
 144  * @mtd:        MTD device structure
 145  *
 146  * Default read function for 16bit buswith without
 147  * endianess conversion
 148  */
 149 static u16 nand_read_word(struct mtd_info *mtd)
 150 {
 151         struct nand_chip *chip = mtd->priv;
 152         return readw(chip->IO_ADDR_R);
 153 }
 154
 155 /**
 156  * nand_select_chip - [DEFAULT] control CE line
 157  * @mtd:        MTD device structure
 158  * @chip:       chipnumber to select, -1 for deselect
 159  *
 160  * Default select function for 1 chip devices.
 161  */
 162 static void nand_select_chip(struct mtd_info *mtd, int chipnr)
 163 {
 164         struct nand_chip *chip = mtd->priv;
 165
 166         switch (chipnr) {
 167         case -1:
 168                 chip->cmd_ctrl(mtd, NAND_CMD_NONE, 0 | NAND_CTRL_CHANGE);
 169                 break;
 170         case 0:
 171                 break;
 172
 173         default:
 174                 BUG();
 175         }
 176 }
 177
 178 /**
 179  * nand_write_buf - [DEFAULT] write buffer to chip
 180  * @mtd:        MTD device structure
 181  * @buf:        data buffer
 182  * @len:        number of bytes to write
 183  *
 184  * Default write function for 8bit buswith
 185  */
 186 static void nand_write_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
 187 {
 188         int i;
 189         struct nand_chip *chip = mtd->priv;
 190
 191         for (i = 0; i < len; i++)
 192                 writeb(buf[i], chip->IO_ADDR_W);
 193 }
 194
 195 /**
 196  * nand_read_buf - [DEFAULT] read chip data into buffer
 197  * @mtd:        MTD device structure
 198  * @buf:        buffer to store date
 199  * @len:        number of bytes to read
 200  *
 201  * Default read function for 8bit buswith
 202  */
 203 static void nand_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
 204 {
 205         int i;
 206         struct nand_chip *chip = mtd->priv;
 207
 208         for (i = 0; i < len; i++)
 209                 buf[i] = readb(chip->IO_ADDR_R);
 210 }
 211
 212 /**
 213  * nand_verify_buf - [DEFAULT] Verify chip data against buffer
 214  * @mtd:        MTD device structure
 215  * @buf:        buffer containing the data to compare
 216  * @len:        number of bytes to compare
 217  *
 218  * Default verify function for 8bit buswith
 219  */
 220 static int nand_verify_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
 221 {
 222         int i;
 223         struct nand_chip *chip = mtd->priv;
 224
 225         for (i = 0; i < len; i++)
 226                 if (buf[i] != readb(chip->IO_ADDR_R))
 227                         return -EFAULT;
 228         return 0;
 229 }
 230
 231 /**
 232  * nand_write_buf16 - [DEFAULT] write buffer to chip
 233  * @mtd:        MTD device structure
 234  * @buf:        data buffer
 235  * @len:        number of bytes to write
 236  *
 237  * Default write function for 16bit buswith
 238  */
 239 static void nand_write_buf16(struct mtd_info *mtd, const uint8_t *buf, int len)
 240 {
 241         int i;
 242         struct nand_chip *chip = mtd->priv;
 243         u16 *p = (u16 *) buf;
 244         len >>= 1;
 245
 246         for (i = 0; i < len; i++)
 247                 writew(p[i], chip->IO_ADDR_W);
 248
 249 }
 250
 251 /**
 252  * nand_read_buf16 - [DEFAULT] read chip data into buffer
 253  * @mtd:        MTD device structure
 254  * @buf:        buffer to store date
 255  * @len:        number of bytes to read
 256  *
 257  * Default read function for 16bit buswith
 258  */
 259 static void nand_read_buf16(struct mtd_info *mtd, uint8_t *buf, int len)
 260 {
 261         int i;
 262         struct nand_chip *chip = mtd->priv;
 263         u16 *p = (u16 *) buf;
 264         len >>= 1;
 265
 266         for (i = 0; i < len; i++)
 267                 p[i] = readw(chip->IO_ADDR_R);
 268 }
 269
 270 /**
 271  * nand_verify_buf16 - [DEFAULT] Verify chip data against buffer
 272  * @mtd:        MTD device structure
 273  * @buf:        buffer containing the data to compare
 274  * @len:        number of bytes to compare
 275  *
 276  * Default verify function for 16bit buswith
 277  */
 278 static int nand_verify_buf16(struct mtd_info *mtd, const uint8_t *buf, int len)
 279 {
 280         int i;
 281         struct nand_chip *chip = mtd->priv;
 282         u16 *p = (u16 *) buf;
 283         len >>= 1;
 284
 285         for (i = 0; i < len; i++)
 286                 if (p[i] != readw(chip->IO_ADDR_R))
 287                         return -EFAULT;
 288
 289         return 0;
 290 }
 291
 292 /**
 293  * nand_block_bad - [DEFAULT] Read bad block marker from the chip
 294  * @mtd:        MTD device structure
 295  * @ofs:        offset from device start
 296  * @getchip:    0, if the chip is already selected
 297  *
 298  * Check, if the block is bad.
 299  */
 300 static int nand_block_bad(struct mtd_info *mtd, loff_t ofs, int getchip)
 301 {
 302         int page, chipnr, res = 0;
 303         struct nand_chip *chip = mtd->priv;
 304         u16 bad;
 305
 306         if (getchip) {
 307                 page = (int)(ofs >> chip->page_shift);
 308                 chipnr = (int)(ofs >> chip->chip_shift);
 309
 310                 nand_get_device(chip, mtd, FL_READING);
 311
 312                 /* Select the NAND device */
 313                 chip->select_chip(mtd, chipnr);
 314         } else
 315                 page = (int)ofs;
 316
 317         if (chip->options & NAND_BUSWIDTH_16) {
 318                 chip->cmdfunc(mtd, NAND_CMD_READOOB, chip->badblockpos & 0xFE,
 319                               page & chip->pagemask);
 320                 bad = cpu_to_le16(chip->read_word(mtd));
 321                 if (chip->badblockpos & 0x1)
 322                         bad >>= 8;
 323                 if ((bad & 0xFF) != 0xff)
 324                         res = 1;
 325         } else {
 326                 chip->cmdfunc(mtd, NAND_CMD_READOOB, chip->badblockpos,
 327                               page & chip->pagemask);
 328                 if (chip->read_byte(mtd) != 0xff)
 329                         res = 1;
 330         }
 331
 332         if (getchip)
 333                 nand_release_device(mtd);
 334
 335         return res;
 336 }
 337
 338 /**
 339  * nand_default_block_markbad - [DEFAULT] mark a block bad
 340  * @mtd:        MTD device structure
 341  * @ofs:        offset from device start
 342  *
 343  * This is the default implementation, which can be overridden by
 344  * a hardware specific driver.
 345 */
 346 static int nand_default_block_markbad(struct mtd_info *mtd, loff_t ofs)
 347 {
 348         struct nand_chip *chip = mtd->priv;
 349         uint8_t buf[2] = { 0, 0 };
 350         int block, ret;
 351
 352         /* Get block number */
 353         block = ((int)ofs) >> chip->bbt_erase_shift;
 354         if (chip->bbt)
 355                 chip->bbt[block >> 2] |= 0x01 << ((block & 0x03) << 1);
 356
 357         /* Do we have a flash based bad block table ? */
 358         if (chip->options & NAND_USE_FLASH_BBT)
 359                 ret = nand_update_bbt(mtd, ofs);
 360         else {
 361                 /* We write two bytes, so we dont have to mess with 16 bit
 362                  * access
 363                  */
 364                 ofs += mtd->oobsize;
 365                 chip->ops.len = 2;
 366                 chip->ops.datbuf = NULL;
 367                 chip->ops.oobbuf = buf;
 368                 chip->ops.ooboffs = chip->badblockpos & ~0x01;
 369
 370                 ret = nand_do_write_oob(mtd, ofs, &chip->ops);
 371         }
 372         if (!ret)
 373                 mtd->ecc_stats.badblocks++;
 374         return ret;
 375 }
 376
 377 /**
 378  * nand_check_wp - [GENERIC] check if the chip is write protected
 379  * @mtd:        MTD device structure
 380  * Check, if the device is write protected
 381  *
 382  * The function expects, that the device is already selected
 383  */
 384 static int nand_check_wp(struct mtd_info *mtd)
 385 {
 386         struct nand_chip *chip = mtd->priv;
 387         /* Check the WP bit */
 388         chip->cmdfunc(mtd, NAND_CMD_STATUS, -1, -1);
 389         return (chip->read_byte(mtd) & NAND_STATUS_WP) ? 0 : 1;
 390 }
 391
 392 /**
 393  * nand_block_checkbad - [GENERIC] Check if a block is marked bad
 394  * @mtd:        MTD device structure
 395  * @ofs:        offset from device start
 396  * @getchip:    0, if the chip is already selected
 397  * @allowbbt:   1, if its allowed to access the bbt area
 398  *
 399  * Check, if the block is bad. Either by reading the bad block table or
 400  * calling of the scan function.
 401  */
 402 static int nand_block_checkbad(struct mtd_info *mtd, loff_t ofs, int getchip,
 403                                int allowbbt)
 404 {
 405         struct nand_chip *chip = mtd->priv;
 406
 407         if (!chip->bbt)
 408                 return chip->block_bad(mtd, ofs, getchip);
 409
 410         /* Return info from the table */
 411         return nand_isbad_bbt(mtd, ofs, allowbbt);
 412 }
 413
 414 /*
 415  * Wait for the ready pin, after a command
 416  * The timeout is catched later.
 417  */
 418 static void nand_wait_ready(struct mtd_info *mtd)
 419 {
 420         struct nand_chip *chip = mtd->priv;
 421         unsigned long timeo = jiffies + 2;
 422
 423         led_trigger_event(nand_led_trigger, LED_FULL);
 424         /* wait until command is processed or timeout occures */
 425         do {
 426                 if (chip->dev_ready(mtd))
 427                         break;
 428                 touch_softlockup_watchdog();
 429         } while (time_before(jiffies, timeo));
 430         led_trigger_event(nand_led_trigger, LED_OFF);
 431 }
 432
 433 /**
 434  * nand_command - [DEFAULT] Send command to NAND device
 435  * @mtd:        MTD device structure
 436  * @command:    the command to be sent
 437  * @column:     the column address for this command, -1 if none
 438  * @page_addr:  the page address for this command, -1 if none
 439  *
 440  * Send command to NAND device. This function is used for small page
 441  * devices (256/512 Bytes per page)
 442  */
 443 static void nand_command(struct mtd_info *mtd, unsigned int command,
 444                          int column, int page_addr)
 445 {
 446         register struct nand_chip *chip = mtd->priv;
 447         int ctrl = NAND_CTRL_CLE | NAND_CTRL_CHANGE;
 448
 449         /*
 450          * Write out the command to the device.
 451          */
 452         if (command == NAND_CMD_SEQIN) {
 453                 int readcmd;
 454
 455                 if (column >= mtd->writesize) {
 456                         /* OOB area */
 457                         column -= mtd->writesize;
 458                         readcmd = NAND_CMD_READOOB;
 459                 } else if (column < 256) {
 460                         /* First 256 bytes --> READ0 */
 461                         readcmd = NAND_CMD_READ0;
 462                 } else {
 463                         column -= 256;
 464                         readcmd = NAND_CMD_READ1;
 465                 }
 466                 chip->cmd_ctrl(mtd, readcmd, ctrl);
 467                 ctrl &= ~NAND_CTRL_CHANGE;
 468         }
 469         chip->cmd_ctrl(mtd, command, ctrl);
 470
 471         /*
 472          * Address cycle, when necessary
 473          */
 474         ctrl = NAND_CTRL_ALE | NAND_CTRL_CHANGE;
 475         /* Serially input address */
 476         if (column != -1) {
 477                 /* Adjust columns for 16 bit buswidth */
 478                 if (chip->options & NAND_BUSWIDTH_16)
 479                         column >>= 1;
 480                 chip->cmd_ctrl(mtd, column, ctrl);
 481                 ctrl &= ~NAND_CTRL_CHANGE;
 482         }
 483         if (page_addr != -1) {
 484                 chip->cmd_ctrl(mtd, page_addr, ctrl);
 485                 ctrl &= ~NAND_CTRL_CHANGE;
 486                 chip->cmd_ctrl(mtd, page_addr >> 8, ctrl);
 487                 /* One more address cycle for devices > 32MiB */
 488                 if (chip->chipsize > (32 << 20))
 489                         chip->cmd_ctrl(mtd, page_addr >> 16, ctrl);
 490         }
 491         chip->cmd_ctrl(mtd, NAND_CMD_NONE, NAND_NCE | NAND_CTRL_CHANGE);
 492
 493         /*
 494          * program and erase have their own busy handlers
 495          * status and sequential in needs no delay
 496          */
 497         switch (command) {
 498
 499         case NAND_CMD_PAGEPROG:
 500         case NAND_CMD_ERASE1:
 501         case NAND_CMD_ERASE2:
 502         case NAND_CMD_SEQIN:
 503         case NAND_CMD_STATUS:
 504                 return;
 505
 506         case NAND_CMD_RESET:
 507                 if (chip->dev_ready)
 508                         break;
 509                 udelay(chip->chip_delay);
 510                 chip->cmd_ctrl(mtd, NAND_CMD_STATUS,
 511                                NAND_CTRL_CLE | NAND_CTRL_CHANGE);
 512                 chip->cmd_ctrl(mtd,
 513                                NAND_CMD_NONE, NAND_NCE | NAND_CTRL_CHANGE);
 514                 while (!(chip->read_byte(mtd) & NAND_STATUS_READY)) ;
 515                 return;
 516
 517                 /* This applies to read commands */
 518         default:
 519                 /*
 520                  * If we don't have access to the busy pin, we apply the given
 521                  * command delay
 522                  */
 523                 if (!chip->dev_ready) {
 524                         udelay(chip->chip_delay);
 525                         return;
 526                 }
 527         }
 528         /* Apply this short delay always to ensure that we do wait tWB in
 529          * any case on any machine. */
 530         ndelay(100);
 531
 532         nand_wait_ready(mtd);
 533 }
 534
 535 /**
 536  * nand_command_lp - [DEFAULT] Send command to NAND large page device
 537  * @mtd:        MTD device structure
 538  * @command:    the command to be sent
 539  * @column:     the column address for this command, -1 if none
 540  * @page_addr:  the page address for this command, -1 if none
 541  *
 542  * Send command to NAND device. This is the version for the new large page
 543  * devices We dont have the separate regions as we have in the small page
 544  * devices.  We must emulate NAND_CMD_READOOB to keep the code compatible.
 545  *
 546  */
 547 static void nand_command_lp(struct mtd_info *mtd, unsigned int command,
 548                             int column, int page_addr)
 549 {
 550         register struct nand_chip *chip = mtd->priv;
 551
 552         /* Emulate NAND_CMD_READOOB */
 553         if (command == NAND_CMD_READOOB) {
 554                 column += mtd->writesize;
 555                 command = NAND_CMD_READ0;
 556         }
 557
 558         /* Command latch cycle */
 559         chip->cmd_ctrl(mtd, command & 0xff,
 560                        NAND_NCE | NAND_CLE | NAND_CTRL_CHANGE);
 561
 562         if (column != -1 || page_addr != -1) {
 563                 int ctrl = NAND_CTRL_CHANGE | NAND_NCE | NAND_ALE;
 564
 565                 /* Serially input address */
 566                 if (column != -1) {
 567                         /* Adjust columns for 16 bit buswidth */
 568                         if (chip->options & NAND_BUSWIDTH_16)
 569                                 column >>= 1;
 570                         chip->cmd_ctrl(mtd, column, ctrl);
 571                         ctrl &= ~NAND_CTRL_CHANGE;
 572                         chip->cmd_ctrl(mtd, column >> 8, ctrl);
 573                 }
 574                 if (page_addr != -1) {
 575                         chip->cmd_ctrl(mtd, page_addr, ctrl);
 576                         chip->cmd_ctrl(mtd, page_addr >> 8,
 577                                        NAND_NCE | NAND_ALE);
 578                         /* One more address cycle for devices > 128MiB */
 579                         if (chip->chipsize > (128 << 20))
 580                                 chip->cmd_ctrl(mtd, page_addr >> 16,
 581                                                NAND_NCE | NAND_ALE);
 582                 }
 583         }
 584         chip->cmd_ctrl(mtd, NAND_CMD_NONE, NAND_NCE | NAND_CTRL_CHANGE);
 585
 586         /*
 587          * program and erase have their own busy handlers
 588          * status, sequential in, and deplete1 need no delay
 589          */
 590         switch (command) {
 591
 592         case NAND_CMD_CACHEDPROG:
 593         case NAND_CMD_PAGEPROG:
 594         case NAND_CMD_ERASE1:
 595         case NAND_CMD_ERASE2:
 596         case NAND_CMD_SEQIN:
 597         case NAND_CMD_RNDIN:
 598         case NAND_CMD_STATUS:
 599         case NAND_CMD_DEPLETE1:
 600                 return;
 601
 602                 /*
 603                  * read error status commands require only a short delay
 604                  */
 605         case NAND_CMD_STATUS_ERROR:
 606         case NAND_CMD_STATUS_ERROR0:
 607         case NAND_CMD_STATUS_ERROR1:
 608         case NAND_CMD_STATUS_ERROR2:
 609         case NAND_CMD_STATUS_ERROR3:
 610                 udelay(chip->chip_delay);
 611                 return;
 612
 613         case NAND_CMD_RESET:
 614                 if (chip->dev_ready)
 615                         break;
 616                 udelay(chip->chip_delay);
 617                 chip->cmd_ctrl(mtd, NAND_CMD_STATUS,
 618                                NAND_NCE | NAND_CLE | NAND_CTRL_CHANGE);
 619                 chip->cmd_ctrl(mtd, NAND_CMD_NONE,
 620                                NAND_NCE | NAND_CTRL_CHANGE);
 621                 while (!(chip->read_byte(mtd) & NAND_STATUS_READY)) ;
 622                 return;
 623
 624         case NAND_CMD_RNDOUT:
 625                 /* No ready / busy check necessary */
 626                 chip->cmd_ctrl(mtd, NAND_CMD_RNDOUTSTART,
 627                                NAND_NCE | NAND_CLE | NAND_CTRL_CHANGE);
 628                 chip->cmd_ctrl(mtd, NAND_CMD_NONE,
 629                                NAND_NCE | NAND_CTRL_CHANGE);
 630                 return;
 631
 632         case NAND_CMD_READ0:
 633                 chip->cmd_ctrl(mtd, NAND_CMD_READSTART,
 634                                NAND_NCE | NAND_CLE | NAND_CTRL_CHANGE);
 635                 chip->cmd_ctrl(mtd, NAND_CMD_NONE,
 636                                NAND_NCE | NAND_CTRL_CHANGE);
 637
 638                 /* This applies to read commands */
 639         default:
 640                 /*
 641                  * If we don't have access to the busy pin, we apply the given
 642                  * command delay
 643                  */
 644                 if (!chip->dev_ready) {
 645                         udelay(chip->chip_delay);
 646                         return;
 647                 }
 648         }
 649
 650         /* Apply this short delay always to ensure that we do wait tWB in
 651          * any case on any machine. */
 652         ndelay(100);
 653
 654         nand_wait_ready(mtd);
 655 }
 656
 657 /**
 658  * nand_get_device - [GENERIC] Get chip for selected access
 659  * @this:       the nand chip descriptor
 660  * @mtd:        MTD device structure
 661  * @new_state:  the state which is requested
 662  *
 663  * Get the device and lock it for exclusive access
 664  */
 665 static int
 666 nand_get_device(struct nand_chip *chip, struct mtd_info *mtd, int new_state)
 667 {
 668         spinlock_t *lock = &chip->controller->lock;
 669         wait_queue_head_t *wq = &chip->controller->wq;
 670         DECLARE_WAITQUEUE(wait, current);
 671  retry:
 672         spin_lock(lock);
 673
 674         /* Hardware controller shared among independend devices */
 675         /* Hardware controller shared among independend devices */
 676         if (!chip->controller->active)
 677                 chip->controller->active = chip;
 678
 679         if (chip->controller->active == chip && chip->state == FL_READY) {
 680                 chip->state = new_state;
 681                 spin_unlock(lock);
 682                 return 0;
 683         }
 684         if (new_state == FL_PM_SUSPENDED) {
 685                 spin_unlock(lock);
 686                 return (chip->state == FL_PM_SUSPENDED) ? 0 : -EAGAIN;
 687         }
 688         set_current_state(TASK_UNINTERRUPTIBLE);
 689         add_wait_queue(wq, &wait);
 690         spin_unlock(lock);
 691         schedule();
 692         remove_wait_queue(wq, &wait);
 693         goto retry;
 694 }
 695
 696 /**
 697  * nand_wait - [DEFAULT]  wait until the command is done
 698  * @mtd:        MTD device structure
 699  * @this:       NAND chip structure
 700  *
 701  * Wait for command done. This applies to erase and program only
 702  * Erase can take up to 400ms and program up to 20ms according to
 703  * general NAND and SmartMedia specs
 704  *
 705 */
 706 static int nand_wait(struct mtd_info *mtd, struct nand_chip *chip)
 707 {
 708
 709         unsigned long timeo = jiffies;
 710         int status, state = chip->state;
 711
 712         if (state == FL_ERASING)
 713                 timeo += (HZ * 400) / 1000;
 714         else
 715                 timeo += (HZ * 20) / 1000;
 716
 717         led_trigger_event(nand_led_trigger, LED_FULL);
 718
 719         /* Apply this short delay always to ensure that we do wait tWB in
 720          * any case on any machine. */
 721         ndelay(100);
 722
 723         if ((state == FL_ERASING) && (chip->options & NAND_IS_AND))
 724                 chip->cmdfunc(mtd, NAND_CMD_STATUS_MULTI, -1, -1);
 725         else
 726                 chip->cmdfunc(mtd, NAND_CMD_STATUS, -1, -1);
 727
 728         while (time_before(jiffies, timeo)) {
 729                 if (chip->dev_ready) {
 730                         if (chip->dev_ready(mtd))
 731                                 break;
 732                 } else {
 733                         if (chip->read_byte(mtd) & NAND_STATUS_READY)
 734                                 break;
 735                 }
 736                 cond_resched();
 737         }
 738         led_trigger_event(nand_led_trigger, LED_OFF);
 739
 740         status = (int)chip->read_byte(mtd);
 741         return status;
 742 }
 743
 744 /**
 745  * nand_read_page_raw - [Intern] read raw page data without ecc
 746  * @mtd:        mtd info structure
 747  * @chip:       nand chip info structure
 748  * @buf:        buffer to store read data
 749  */
 750 static int nand_read_page_raw(struct mtd_info *mtd, struct nand_chip *chip,
 751                               uint8_t *buf)
 752 {
 753         chip->read_buf(mtd, buf, mtd->writesize);
 754         chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
 755         return 0;
 756 }
 757
 758 /**
 759  * nand_read_page_swecc - {REPLACABLE] software ecc based page read function
 760  * @mtd:        mtd info structure
 761  * @chip:       nand chip info structure
 762  * @buf:        buffer to store read data
 763  */
 764 static int nand_read_page_swecc(struct mtd_info *mtd, struct nand_chip *chip,
 765                                 uint8_t *buf)
 766 {
 767         int i, eccsize = chip->ecc.size;
 768         int eccbytes = chip->ecc.bytes;
 769         int eccsteps = chip->ecc.steps;
 770         uint8_t *p = buf;
 771         uint8_t *ecc_calc = chip->buffers.ecccalc;
 772         uint8_t *ecc_code = chip->buffers.ecccode;
 773         int *eccpos = chip->ecc.layout->eccpos;
 774
 775         nand_read_page_raw(mtd, chip, buf);
 776
 777         for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize)
 778                 chip->ecc.calculate(mtd, p, &ecc_calc[i]);
 779
 780         for (i = 0; i < chip->ecc.total; i++)
 781                 ecc_code[i] = chip->oob_poi[eccpos[i]];
 782
 783         eccsteps = chip->ecc.steps;
 784         p = buf;
 785
 786         for (i = 0 ; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
 787                 int stat;
 788
 789                 stat = chip->ecc.correct(mtd, p, &ecc_code[i], &ecc_calc[i]);
 790                 if (stat == -1)
 791                         mtd->ecc_stats.failed++;
 792                 else
 793                         mtd->ecc_stats.corrected += stat;
 794         }
 795         return 0;
 796 }
 797
 798 /**
 799  * nand_read_page_hwecc - {REPLACABLE] hardware ecc based page read function
 800  * @mtd:        mtd info structure
 801  * @chip:       nand chip info structure
 802  * @buf:        buffer to store read data
 803  *
 804  * Not for syndrome calculating ecc controllers which need a special oob layout
 805  */
 806 static int nand_read_page_hwecc(struct mtd_info *mtd, struct nand_chip *chip,
 807                                 uint8_t *buf)
 808 {
 809         int i, eccsize = chip->ecc.size;
 810         int eccbytes = chip->ecc.bytes;
 811         int eccsteps = chip->ecc.steps;
 812         uint8_t *p = buf;
 813         uint8_t *ecc_calc = chip->buffers.ecccalc;
 814         uint8_t *ecc_code = chip->buffers.ecccode;
 815         int *eccpos = chip->ecc.layout->eccpos;
 816
 817         for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
 818                 chip->ecc.hwctl(mtd, NAND_ECC_READ);
 819                 chip->read_buf(mtd, p, eccsize);
 820                 chip->ecc.calculate(mtd, p, &ecc_calc[i]);
 821         }
 822         chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
 823
 824         for (i = 0; i < chip->ecc.total; i++)
 825                 ecc_code[i] = chip->oob_poi[eccpos[i]];
 826
 827         eccsteps = chip->ecc.steps;
 828         p = buf;
 829
 830         for (i = 0 ; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
 831                 int stat;
 832
 833                 stat = chip->ecc.correct(mtd, p, &ecc_code[i], &ecc_calc[i]);
 834                 if (stat == -1)
 835                         mtd->ecc_stats.failed++;
 836                 else
 837                         mtd->ecc_stats.corrected += stat;
 838         }
 839         return 0;
 840 }
 841
 842 /**
 843  * nand_read_page_syndrome - {REPLACABLE] hardware ecc syndrom based page read
 844  * @mtd:        mtd info structure
 845  * @chip:       nand chip info structure
 846  * @buf:        buffer to store read data
 847  *
 848  * The hw generator calculates the error syndrome automatically. Therefor
 849  * we need a special oob layout and handling.
 850  */
 851 static int nand_read_page_syndrome(struct mtd_info *mtd, struct nand_chip *chip,
 852                                    uint8_t *buf)
 853 {
 854         int i, eccsize = chip->ecc.size;
 855         int eccbytes = chip->ecc.bytes;
 856         int eccsteps = chip->ecc.steps;
 857         uint8_t *p = buf;
 858         uint8_t *oob = chip->oob_poi;
 859
 860         for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
 861                 int stat;
 862
 863                 chip->ecc.hwctl(mtd, NAND_ECC_READ);
 864                 chip->read_buf(mtd, p, eccsize);
 865
 866                 if (chip->ecc.prepad) {
 867                         chip->read_buf(mtd, oob, chip->ecc.prepad);
 868                         oob += chip->ecc.prepad;
 869                 }
 870
 871                 chip->ecc.hwctl(mtd, NAND_ECC_READSYN);
 872                 chip->read_buf(mtd, oob, eccbytes);
 873                 stat = chip->ecc.correct(mtd, p, oob, NULL);
 874
 875                 if (stat == -1)
 876                         mtd->ecc_stats.failed++;
 877                 else
 878                         mtd->ecc_stats.corrected += stat;
 879
 880                 oob += eccbytes;
 881
 882                 if (chip->ecc.postpad) {
 883                         chip->read_buf(mtd, oob, chip->ecc.postpad);
 884                         oob += chip->ecc.postpad;
 885                 }
 886         }
 887
 888         /* Calculate remaining oob bytes */
 889         i = mtd->oobsize - (oob - chip->oob_poi);
 890         if (i)
 891                 chip->read_buf(mtd, oob, i);
 892
 893         return 0;
 894 }
 895
 896 /**
 897  * nand_transfer_oob - [Internal] Transfer oob to client buffer
 898  * @chip:       nand chip structure
 899  * @ops:        oob ops structure
 900  */
 901 static uint8_t *nand_transfer_oob(struct nand_chip *chip, uint8_t *oob,
 902                                   struct mtd_oob_ops *ops)
 903 {
 904         size_t len = ops->ooblen;
 905
 906         switch(ops->mode) {
 907
 908         case MTD_OOB_PLACE:
 909         case MTD_OOB_RAW:
 910                 memcpy(oob, chip->oob_poi + ops->ooboffs, len);
 911                 return oob + len;
 912
 913         case MTD_OOB_AUTO: {
 914                 struct nand_oobfree *free = chip->ecc.layout->oobfree;
 915                 uint32_t boffs = 0, roffs = ops->ooboffs;
 916                 size_t bytes = 0;
 917
 918                 for(; free->length && len; free++, len -= bytes) {
 919                         /* Read request not from offset 0 ? */
 920                         if (unlikely(roffs)) {
 921                                 if (roffs >= free->length) {
 922                                         roffs -= free->length;
 923                                         continue;
 924                                 }
 925                                 boffs = free->offset + roffs;
 926                                 bytes = min_t(size_t, len,
 927                                               (free->length - roffs));
 928                                 roffs = 0;
 929                         } else {
 930                                 bytes = min_t(size_t, len, free->length);
 931                                 boffs = free->offset;
 932                         }
 933                         memcpy(oob, chip->oob_poi + boffs, bytes);
 934                         oob += bytes;
 935                 }
 936                 return oob;
 937         }
 938         default:
 939                 BUG();
 940         }
 941         return NULL;
 942 }
 943
 944 /**
 945  * nand_do_read_ops - [Internal] Read data with ECC
 946  *
 947  * @mtd:        MTD device structure
 948  * @from:       offset to read from
 949  *
 950  * Internal function. Called with chip held.
 951  */
 952 static int nand_do_read_ops(struct mtd_info *mtd, loff_t from,
 953                             struct mtd_oob_ops *ops)
 954 {
 955         int chipnr, page, realpage, col, bytes, aligned;
 956         struct nand_chip *chip = mtd->priv;
 957         struct mtd_ecc_stats stats;
 958         int blkcheck = (1 << (chip->phys_erase_shift - chip->page_shift)) - 1;
 959         int sndcmd = 1;
 960         int ret = 0;
 961         uint32_t readlen = ops->len;
 962         uint8_t *bufpoi, *oob, *buf;
 963
 964         stats = mtd->ecc_stats;
 965
 966         chipnr = (int)(from >> chip->chip_shift);
 967         chip->select_chip(mtd, chipnr);
 968
 969         realpage = (int)(from >> chip->page_shift);
 970         page = realpage & chip->pagemask;
 971
 972         col = (int)(from & (mtd->writesize - 1));
 973         chip->oob_poi = chip->buffers.oobrbuf;
 974
 975         buf = ops->datbuf;
 976         oob = ops->oobbuf;
 977
 978         while(1) {
 979                 bytes = min(mtd->writesize - col, readlen);
 980                 aligned = (bytes == mtd->writesize);
 981
 982                 /* Is the current page in the buffer ? */
 983                 if (realpage != chip->pagebuf || oob) {
 984                         bufpoi = aligned ? buf : chip->buffers.databuf;
 985
 986                         if (likely(sndcmd)) {
 987                                 chip->cmdfunc(mtd, NAND_CMD_READ0, 0x00, page);
 988                                 sndcmd = 0;
 989                         }
 990
 991                         /* Now read the page into the buffer */
 992                         ret = chip->ecc.read_page(mtd, chip, bufpoi);
 993                         if (ret < 0)
 994                                 break;
 995
 996                         /* Transfer not aligned data */
 997                         if (!aligned) {
 998                                 chip->pagebuf = realpage;
 999                                 memcpy(buf, chip->buffers.databuf + col, bytes);
1000                         }
1001
1002                         buf += bytes;
1003
1004                         if (unlikely(oob)) {
1005                                 /* Raw mode does data:oob:data:oob */
1006                                 if (ops->mode != MTD_OOB_RAW)
1007                                         oob = nand_transfer_oob(chip, oob, ops);
1008                                 else
1009                                         buf = nand_transfer_oob(chip, buf, ops);
1010                         }
1011
1012                         if (!(chip->options & NAND_NO_READRDY)) {
1013                                 /*
1014                                  * Apply delay or wait for ready/busy pin. Do
1015                                  * this before the AUTOINCR check, so no
1016                                  * problems arise if a chip which does auto
1017                                  * increment is marked as NOAUTOINCR by the
1018                                  * board driver.
1019                                  */
1020                                 if (!chip->dev_ready)
1021                                         udelay(chip->chip_delay);
1022                                 else
1023                                         nand_wait_ready(mtd);
1024                         }
1025                 } else {
1026                         memcpy(buf, chip->buffers.databuf + col, bytes);
1027                         buf += bytes;
1028                 }
1029
1030                 readlen -= bytes;
1031
1032                 if (!readlen)
1033                         break;
1034
1035                 /* For subsequent reads align to page boundary. */
1036                 col = 0;
1037                 /* Increment page address */
1038                 realpage++;
1039
1040                 page = realpage & chip->pagemask;
1041                 /* Check, if we cross a chip boundary */
1042                 if (!page) {
1043                         chipnr++;
1044                         chip->select_chip(mtd, -1);
1045                         chip->select_chip(mtd, chipnr);
1046                 }
1047
1048                 /* Check, if the chip supports auto page increment
1049                  * or if we have hit a block boundary.
1050                  */
1051                 if (!NAND_CANAUTOINCR(chip) || !(page & blkcheck))
1052                         sndcmd = 1;
1053         }
1054
1055         ops->retlen = ops->len - (size_t) readlen;
1056
1057         if (ret)
1058                 return ret;
1059
1060         if (mtd->ecc_stats.failed - stats.failed)
1061                 return -EBADMSG;
1062
1063         return  mtd->ecc_stats.corrected - stats.corrected ? -EUCLEAN : 0;
1064 }
1065
1066 /**
1067  * nand_read - [MTD Interface] MTD compability function for nand_do_read_ecc
1068  * @mtd:        MTD device structure
1069  * @from:       offset to read from
1070  * @len:        number of bytes to read
1071  * @retlen:     pointer to variable to store the number of read bytes
1072  * @buf:        the databuffer to put data
1073  *
1074  * Get hold of the chip and call nand_do_read
1075  */
1076 static int nand_read(struct mtd_info *mtd, loff_t from, size_t len,
1077                      size_t *retlen, uint8_t *buf)
1078 {
1079         struct nand_chip *chip = mtd->priv;
1080         int ret;
1081
1082         /* Do not allow reads past end of device */
1083         if ((from + len) > mtd->size)
1084                 return -EINVAL;
1085         if (!len)
1086                 return 0;
1087
1088         nand_get_device(chip, mtd, FL_READING);
1089
1090         chip->ops.len = len;
1091         chip->ops.datbuf = buf;
1092         chip->ops.oobbuf = NULL;
1093
1094         ret = nand_do_read_ops(mtd, from, &chip->ops);
1095
1096         nand_release_device(mtd);
1097
1098         *retlen = chip->ops.retlen;
1099         return ret;
1100 }
1101
1102 /**
1103  * nand_read_oob_std - [REPLACABLE] the most common OOB data read function
1104  * @mtd:        mtd info structure
1105  * @chip:       nand chip info structure
1106  * @page:       page number to read
1107  * @sndcmd:     flag whether to issue read command or not
1108  */
1109 static int nand_read_oob_std(struct mtd_info *mtd, struct nand_chip *chip,
1110                              int page, int sndcmd)
1111 {
1112         if (sndcmd) {
1113                 chip->cmdfunc(mtd, NAND_CMD_READOOB, 0, page);
1114                 sndcmd = 0;
1115         }
1116         chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
1117         return sndcmd;
1118 }
1119
1120 /**
1121  * nand_read_oob_syndrome - [REPLACABLE] OOB data read function for HW ECC
1122  *                          with syndromes
1123  * @mtd:        mtd info structure
1124  * @chip:       nand chip info structure
1125  * @page:       page number to read
1126  * @sndcmd:     flag whether to issue read command or not
1127  */
1128 static int nand_read_oob_syndrome(struct mtd_info *mtd, struct nand_chip *chip,
1129                                   int page, int sndcmd)
1130 {
1131         uint8_t *buf = chip->oob_poi;
1132         int length = mtd->oobsize;
1133         int chunk = chip->ecc.bytes + chip->ecc.prepad + chip->ecc.postpad;
1134         int eccsize = chip->ecc.size;
1135         uint8_t *bufpoi = buf;
1136         int i, toread, sndrnd = 0, pos;
1137
1138         chip->cmdfunc(mtd, NAND_CMD_READ0, chip->ecc.size, page);
1139         for (i = 0; i < chip->ecc.steps; i++) {
1140                 if (sndrnd) {
1141                         pos = eccsize + i * (eccsize + chunk);
1142                         if (mtd->writesize > 512)
1143                                 chip->cmdfunc(mtd, NAND_CMD_RNDOUT, pos, -1);
1144                         else
1145                                 chip->cmdfunc(mtd, NAND_CMD_READ0, pos, page);
1146                 } else
1147                         sndrnd = 1;
1148                 toread = min_t(int, length, chunk);
1149                 chip->read_buf(mtd, bufpoi, toread);
1150                 bufpoi += toread;
1151                 length -= toread;
1152         }
1153         if (length > 0)
1154                 chip->read_buf(mtd, bufpoi, length);
1155
1156         return 1;
1157 }
1158
1159 /**
1160  * nand_write_oob_std - [REPLACABLE] the most common OOB data write function
1161  * @mtd:        mtd info structure
1162  * @chip:       nand chip info structure
1163  * @page:       page number to write
1164  */
1165 static int nand_write_oob_std(struct mtd_info *mtd, struct nand_chip *chip,
1166                               int page)
1167 {
1168         int status = 0;
1169         const uint8_t *buf = chip->oob_poi;
1170         int length = mtd->oobsize;
1171
1172         chip->cmdfunc(mtd, NAND_CMD_SEQIN, mtd->writesize, page);
1173         chip->write_buf(mtd, buf, length);
1174         /* Send command to program the OOB data */
1175         chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
1176
1177         status = chip->waitfunc(mtd, chip);
1178
1179         return status & NAND_STATUS_FAIL ? -EIO : 0;
1180 }
1181
1182 /**
1183  * nand_write_oob_syndrome - [REPLACABLE] OOB data write function for HW ECC
1184  *                           with syndrome - only for large page flash !
1185  * @mtd:        mtd info structure
1186  * @chip:       nand chip info structure
1187  * @page:       page number to write
1188  */
1189 static int nand_write_oob_syndrome(struct mtd_info *mtd,
1190                                    struct nand_chip *chip, int page)
1191 {
1192         int chunk = chip->ecc.bytes + chip->ecc.prepad + chip->ecc.postpad;
1193         int eccsize = chip->ecc.size, length = mtd->oobsize;
1194         int i, len, pos, status = 0, sndcmd = 0, steps = chip->ecc.steps;
1195         const uint8_t *bufpoi = chip->oob_poi;
1196
1197         /*
1198          * data-ecc-data-ecc ... ecc-oob
1199          * or
1200          * data-pad-ecc-pad-data-pad .... ecc-pad-oob
1201          */
1202         if (!chip->ecc.prepad && !chip->ecc.postpad) {
1203                 pos = steps * (eccsize + chunk);
1204                 steps = 0;
1205         } else
1206                 pos = eccsize + chunk;
1207
1208         chip->cmdfunc(mtd, NAND_CMD_SEQIN, pos, page);
1209         for (i = 0; i < steps; i++) {
1210                 if (sndcmd) {
1211                         if (mtd->writesize <= 512) {
1212                                 uint32_t fill = 0xFFFFFFFF;
1213
1214                                 len = eccsize;
1215                                 while (len > 0) {
1216                                         int num = min_t(int, len, 4);
1217                                         chip->write_buf(mtd, (uint8_t *)&fill,
1218                                                         num);
1219                                         len -= num;
1220                                 }
1221                         } else {
1222                                 pos = eccsize + i * (eccsize + chunk);
1223                                 chip->cmdfunc(mtd, NAND_CMD_RNDIN, pos, -1);
1224                         }
1225                 } else
1226                         sndcmd = 1;
1227                 len = min_t(int, length, chunk);
1228                 chip->write_buf(mtd, bufpoi, len);
1229                 bufpoi += len;
1230                 length -= len;
1231         }
1232         if (length > 0)
1233                 chip->write_buf(mtd, bufpoi, length);
1234
1235         chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
1236         status = chip->waitfunc(mtd, chip);
1237
1238         return status & NAND_STATUS_FAIL ? -EIO : 0;
1239 }
1240
1241 /**
1242  * nand_do_read_oob - [Intern] NAND read out-of-band
1243  * @mtd:        MTD device structure
1244  * @from:       offset to read from
1245  * @ops:        oob operations description structure
1246  *
1247  * NAND read out-of-band data from the spare area
1248  */
1249 static int nand_do_read_oob(struct mtd_info *mtd, loff_t from,
1250                             struct mtd_oob_ops *ops)
1251 {
1252         int page, realpage, chipnr, sndcmd = 1;
1253         struct nand_chip *chip = mtd->priv;
1254         int blkcheck = (1 << (chip->phys_erase_shift - chip->page_shift)) - 1;
1255         int readlen = ops->len;
1256         uint8_t *buf = ops->oobbuf;
1257
1258         DEBUG(MTD_DEBUG_LEVEL3, "nand_read_oob: from = 0x%08Lx, len = %i\n",
1259               (unsigned long long)from, readlen);
1260
1261         chipnr = (int)(from >> chip->chip_shift);
1262         chip->select_chip(mtd, chipnr);
1263
1264         /* Shift to get page */
1265         realpage = (int)(from >> chip->page_shift);
1266         page = realpage & chip->pagemask;
1267
1268         chip->oob_poi = chip->buffers.oobrbuf;
1269
1270         while(1) {
1271                 sndcmd = chip->ecc.read_oob(mtd, chip, page, sndcmd);
1272                 buf = nand_transfer_oob(chip, buf, ops);
1273
1274                 if (!(chip->options & NAND_NO_READRDY)) {
1275                         /*
1276                          * Apply delay or wait for ready/busy pin. Do this
1277                          * before the AUTOINCR check, so no problems arise if a
1278                          * chip which does auto increment is marked as
1279                          * NOAUTOINCR by the board driver.
1280                          */
1281                         if (!chip->dev_ready)
1282                                 udelay(chip->chip_delay);
1283                         else
1284                                 nand_wait_ready(mtd);
1285                 }
1286
1287                 readlen -= ops->ooblen;
1288                 if (!readlen)
1289                         break;
1290
1291                 /* Increment page address */
1292                 realpage++;
1293
1294                 page = realpage & chip->pagemask;
1295                 /* Check, if we cross a chip boundary */
1296                 if (!page) {
1297                         chipnr++;
1298                         chip->select_chip(mtd, -1);
1299                         chip->select_chip(mtd, chipnr);
1300                 }
1301
1302                 /* Check, if the chip supports auto page increment
1303                  * or if we have hit a block boundary.
1304                  */
1305                 if (!NAND_CANAUTOINCR(chip) || !(page & blkcheck))
1306                         sndcmd = 1;
1307         }
1308
1309         ops->retlen = ops->len;
1310         return 0;
1311 }
1312
1313 /**
1314  * nand_read_oob - [MTD Interface] NAND read data and/or out-of-band
1315  * @mtd:        MTD device structure
1316  * @from:       offset to read from
1317  * @ops:        oob operation description structure
1318  *
1319  * NAND read data and/or out-of-band data
1320  */
1321 static int nand_read_oob(struct mtd_info *mtd, loff_t from,
1322                          struct mtd_oob_ops *ops)
1323 {
1324         int (*read_page)(struct mtd_info *mtd, struct nand_chip *chip,
1325                          uint8_t *buf) = NULL;
1326         struct nand_chip *chip = mtd->priv;
1327         int ret = -ENOTSUPP;
1328
1329         ops->retlen = 0;
1330
1331         /* Do not allow reads past end of device */
1332         if ((from + ops->len) > mtd->size) {
1333                 DEBUG(MTD_DEBUG_LEVEL0, "nand_read_oob: "
1334                       "Attempt read beyond end of device\n");
1335                 return -EINVAL;
1336         }
1337
1338         nand_get_device(chip, mtd, FL_READING);
1339
1340         switch(ops->mode) {
1341         case MTD_OOB_PLACE:
1342         case MTD_OOB_AUTO:
1343                 break;
1344
1345         case MTD_OOB_RAW:
1346                 /* Replace the read_page algorithm temporary */
1347                 read_page = chip->ecc.read_page;
1348                 chip->ecc.read_page = nand_read_page_raw;
1349                 break;
1350
1351         default:
1352                 goto out;
1353         }
1354
1355         if (!ops->datbuf)
1356                 ret = nand_do_read_oob(mtd, from, ops);
1357         else
1358                 ret = nand_do_read_ops(mtd, from, ops);
1359
1360         if (unlikely(ops->mode == MTD_OOB_RAW))
1361                 chip->ecc.read_page = read_page;
1362  out:
1363         nand_release_device(mtd);
1364         return ret;
1365 }
1366
1367
1368 /**
1369  * nand_write_page_raw - [Intern] raw page write function
1370  * @mtd:        mtd info structure
1371  * @chip:       nand chip info structure
1372  * @buf:        data buffer
1373  */
1374 static void nand_write_page_raw(struct mtd_info *mtd, struct nand_chip *chip,
1375                                 const uint8_t *buf)
1376 {
1377         chip->write_buf(mtd, buf, mtd->writesize);
1378         chip->write_buf(mtd, chip->oob_poi, mtd->oobsize);
1379 }
1380
1381 /**
1382  * nand_write_page_swecc - {REPLACABLE] software ecc based page write function
1383  * @mtd:        mtd info structure
1384  * @chip:       nand chip info structure
1385  * @buf:        data buffer
1386  */
1387 static void nand_write_page_swecc(struct mtd_info *mtd, struct nand_chip *chip,
1388                                   const uint8_t *buf)
1389 {
1390         int i, eccsize = chip->ecc.size;
1391         int eccbytes = chip->ecc.bytes;
1392         int eccsteps = chip->ecc.steps;
1393         uint8_t *ecc_calc = chip->buffers.ecccalc;
1394         const uint8_t *p = buf;
1395         int *eccpos = chip->ecc.layout->eccpos;
1396
1397         /* Software ecc calculation */
1398         for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize)
1399                 chip->ecc.calculate(mtd, p, &ecc_calc[i]);
1400
1401         for (i = 0; i < chip->ecc.total; i++)
1402                 chip->oob_poi[eccpos[i]] = ecc_calc[i];
1403
1404         nand_write_page_raw(mtd, chip, buf);
1405 }
1406
1407 /**
1408  * nand_write_page_hwecc - {REPLACABLE] hardware ecc based page write function
1409  * @mtd:        mtd info structure
1410  * @chip:       nand chip info structure
1411  * @buf:        data buffer
1412  */
1413 static void nand_write_page_hwecc(struct mtd_info *mtd, struct nand_chip *chip,
1414                                   const uint8_t *buf)
1415 {
1416         int i, eccsize = chip->ecc.size;
1417         int eccbytes = chip->ecc.bytes;
1418         int eccsteps = chip->ecc.steps;
1419         uint8_t *ecc_calc = chip->buffers.ecccalc;
1420         const uint8_t *p = buf;
1421         int *eccpos = chip->ecc.layout->eccpos;
1422
1423         for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
1424                 chip->ecc.hwctl(mtd, NAND_ECC_WRITE);
1425                 chip->write_buf(mtd, p, eccsize);
1426                 chip->ecc.calculate(mtd, p, &ecc_calc[i]);
1427         }
1428
1429         for (i = 0; i < chip->ecc.total; i++)
1430                 chip->oob_poi[eccpos[i]] = ecc_calc[i];
1431
1432         chip->write_buf(mtd, chip->oob_poi, mtd->oobsize);
1433 }
1434
1435 /**
1436  * nand_write_page_syndrome - {REPLACABLE] hardware ecc syndrom based page write
1437  * @mtd:        mtd info structure
1438  * @chip:       nand chip info structure
1439  * @buf:        data buffer
1440  *
1441  * The hw generator calculates the error syndrome automatically. Therefor
1442  * we need a special oob layout and handling.
1443  */
1444 static void nand_write_page_syndrome(struct mtd_info *mtd,
1445                                     struct nand_chip *chip, const uint8_t *buf)
1446 {
1447         int i, eccsize = chip->ecc.size;
1448         int eccbytes = chip->ecc.bytes;
1449         int eccsteps = chip->ecc.steps;
1450         const uint8_t *p = buf;
1451         uint8_t *oob = chip->oob_poi;
1452
1453         for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
1454
1455                 chip->ecc.hwctl(mtd, NAND_ECC_WRITE);
1456                 chip->write_buf(mtd, p, eccsize);
1457
1458                 if (chip->ecc.prepad) {
1459                         chip->write_buf(mtd, oob, chip->ecc.prepad);
1460                         oob += chip->ecc.prepad;
1461                 }
1462
1463                 chip->ecc.calculate(mtd, p, oob);
1464                 chip->write_buf(mtd, oob, eccbytes);
1465                 oob += eccbytes;
1466
1467                 if (chip->ecc.postpad) {
1468                         chip->write_buf(mtd, oob, chip->ecc.postpad);
1469                         oob += chip->ecc.postpad;
1470                 }
1471         }
1472
1473         /* Calculate remaining oob bytes */
1474         i = mtd->oobsize - (oob - chip->oob_poi);
1475         if (i)
1476                 chip->write_buf(mtd, oob, i);
1477 }
1478
1479 /**
1480  * nand_write_page - [INTERNAL] write one page
1481  * @mtd:        MTD device structure
1482  * @chip:       NAND chip descriptor
1483  * @buf:        the data to write
1484  * @page:       page number to write
1485  * @cached:     cached programming
1486  */
1487 static int nand_write_page(struct mtd_info *mtd, struct nand_chip *chip,
1488                            const uint8_t *buf, int page, int cached)
1489 {
1490         int status;
1491
1492         chip->cmdfunc(mtd, NAND_CMD_SEQIN, 0x00, page);
1493
1494         chip->ecc.write_page(mtd, chip, buf);
1495
1496         /*
1497          * Cached progamming disabled for now, Not sure if its worth the
1498          * trouble. The speed gain is not very impressive. (2.3->2.6Mib/s)
1499          */
1500         cached = 0;
1501
1502         if (!cached || !(chip->options & NAND_CACHEPRG)) {
1503
1504                 chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
1505                 status = chip->waitfunc(mtd, chip);
1506                 /*
1507                  * See if operation failed and additional status checks are
1508                  * available
1509                  */
1510                 if ((status & NAND_STATUS_FAIL) && (chip->errstat))
1511                         status = chip->errstat(mtd, chip, FL_WRITING, status,
1512                                                page);
1513
1514                 if (status & NAND_STATUS_FAIL)
1515                         return -EIO;
1516         } else {
1517                 chip->cmdfunc(mtd, NAND_CMD_CACHEDPROG, -1, -1);
1518                 status = chip->waitfunc(mtd, chip);
1519         }
1520
1521 #ifdef CONFIG_MTD_NAND_VERIFY_WRITE
1522         /* Send command to read back the data */
1523         chip->cmdfunc(mtd, NAND_CMD_READ0, 0, page);
1524
1525         if (chip->verify_buf(mtd, buf, mtd->writesize))
1526                 return -EIO;
1527 #endif
1528         return 0;
1529 }
1530
1531 /**
1532  * nand_fill_oob - [Internal] Transfer client buffer to oob
1533  * @chip:       nand chip structure
1534  * @oob:        oob data buffer
1535  * @ops:        oob ops structure
1536  */
1537 static uint8_t *nand_fill_oob(struct nand_chip *chip, uint8_t *oob,
1538                                   struct mtd_oob_ops *ops)
1539 {
1540         size_t len = ops->ooblen;
1541
1542         switch(ops->mode) {
1543
1544         case MTD_OOB_PLACE:
1545         case MTD_OOB_RAW:
1546                 memcpy(chip->oob_poi + ops->ooboffs, oob, len);
1547                 return oob + len;
1548
1549         case MTD_OOB_AUTO: {
1550                 struct nand_oobfree *free = chip->ecc.layout->oobfree;
1551                 uint32_t boffs = 0, woffs = ops->ooboffs;
1552                 size_t bytes = 0;
1553
1554                 for(; free->length && len; free++, len -= bytes) {
1555                         /* Write request not from offset 0 ? */
1556                         if (unlikely(woffs)) {
1557                                 if (woffs >= free->length) {
1558                                         woffs -= free->length;
1559                                         continue;
1560                                 }
1561                                 boffs = free->offset + woffs;
1562                                 bytes = min_t(size_t, len,
1563                                               (free->length - woffs));
1564                                 woffs = 0;
1565                         } else {
1566                                 bytes = min_t(size_t, len, free->length);
1567                                 boffs = free->offset;
1568                         }
1569                         memcpy(chip->oob_poi + woffs, oob, bytes);
1570                         oob += bytes;
1571                 }
1572                 return oob;
1573         }
1574         default:
1575                 BUG();
1576         }
1577         return NULL;
1578 }
1579
1580 #define NOTALIGNED(x) (x & (mtd->writesize-1)) != 0
1581
1582 /**
1583  * nand_do_write_ops - [Internal] NAND write with ECC
1584  * @mtd:        MTD device structure
1585  * @to:         offset to write to
1586  * @ops:        oob operations description structure
1587  *
1588  * NAND write with ECC
1589  */
1590 static int nand_do_write_ops(struct mtd_info *mtd, loff_t to,
1591                              struct mtd_oob_ops *ops)
1592 {
1593         int chipnr, realpage, page, blockmask;
1594         struct nand_chip *chip = mtd->priv;
1595         uint32_t writelen = ops->len;
1596         uint8_t *oob = ops->oobbuf;
1597         uint8_t *buf = ops->datbuf;
1598         int bytes = mtd->writesize;
1599         int ret;
1600
1601         ops->retlen = 0;
1602
1603         /* reject writes, which are not page aligned */
1604         if (NOTALIGNED(to) || NOTALIGNED(ops->len)) {
1605                 printk(KERN_NOTICE "nand_write: "
1606                        "Attempt to write not page aligned data\n");
1607                 return -EINVAL;
1608         }
1609
1610         if (!writelen)
1611                 return 0;
1612
1613         chipnr = (int)(to >> chip->chip_shift);
1614         chip->select_chip(mtd, chipnr);
1615
1616         /* Check, if it is write protected */
1617         if (nand_check_wp(mtd))
1618                 return -EIO;
1619
1620         realpage = (int)(to >> chip->page_shift);
1621         page = realpage & chip->pagemask;
1622         blockmask = (1 << (chip->phys_erase_shift - chip->page_shift)) - 1;
1623
1624         /* Invalidate the page cache, when we write to the cached page */
1625         if (to <= (chip->pagebuf << chip->page_shift) &&
1626             (chip->pagebuf << chip->page_shift) < (to + ops->len))
1627                 chip->pagebuf = -1;
1628
1629         chip->oob_poi = chip->buffers.oobwbuf;
1630
1631         while(1) {
1632                 int cached = writelen > bytes && page != blockmask;
1633
1634                 if (unlikely(oob))
1635                         oob = nand_fill_oob(chip, oob, ops);
1636
1637                 ret = nand_write_page(mtd, chip, buf, page, cached);
1638                 if (ret)
1639                         break;
1640
1641                 writelen -= bytes;
1642                 if (!writelen)
1643                         break;
1644
1645                 buf += bytes;
1646                 realpage++;
1647
1648                 page = realpage & chip->pagemask;
1649                 /* Check, if we cross a chip boundary */
1650                 if (!page) {
1651                         chipnr++;
1652                         chip->select_chip(mtd, -1);
1653                         chip->select_chip(mtd, chipnr);
1654                 }
1655         }
1656
1657         if (unlikely(oob))
1658                 memset(chip->oob_poi, 0xff, mtd->oobsize);
1659
1660         ops->retlen = ops->len - writelen;
1661         return ret;
1662 }
1663
1664 /**
1665  * nand_write - [MTD Interface] NAND write with ECC
1666  * @mtd:        MTD device structure
1667  * @to:         offset to write to
1668  * @len:        number of bytes to write
1669  * @retlen:     pointer to variable to store the number of written bytes
1670  * @buf:        the data to write
1671  *
1672  * NAND write with ECC
1673  */
1674 static int nand_write(struct mtd_info *mtd, loff_t to, size_t len,
1675                           size_t *retlen, const uint8_t *buf)
1676 {
1677         struct nand_chip *chip = mtd->priv;
1678         int ret;
1679
1680         /* Do not allow reads past end of device */
1681         if ((to + len) > mtd->size)
1682                 return -EINVAL;
1683         if (!len)
1684                 return 0;
1685
1686         nand_get_device(chip, mtd, FL_WRITING);
1687
1688         chip->ops.len = len;
1689         chip->ops.datbuf = (uint8_t *)buf;
1690         chip->ops.oobbuf = NULL;
1691
1692         ret = nand_do_write_ops(mtd, to, &chip->ops);
1693
1694         nand_release_device(mtd);
1695
1696         *retlen = chip->ops.retlen;
1697         return ret;
1698 }
1699
1700 /**
1701  * nand_do_write_oob - [MTD Interface] NAND write out-of-band
1702  * @mtd:        MTD device structure
1703  * @to:         offset to write to
1704  * @ops:        oob operation description structure
1705  *
1706  * NAND write out-of-band
1707  */
1708 static int nand_do_write_oob(struct mtd_info *mtd, loff_t to,
1709                              struct mtd_oob_ops *ops)
1710 {
1711         int chipnr, page, status;
1712         struct nand_chip *chip = mtd->priv;
1713
1714         DEBUG(MTD_DEBUG_LEVEL3, "nand_write_oob: to = 0x%08x, len = %i\n",
1715               (unsigned int)to, (int)ops->len);
1716
1717         /* Do not allow write past end of page */
1718         if ((ops->ooboffs + ops->len) > mtd->oobsize) {
1719                 DEBUG(MTD_DEBUG_LEVEL0, "nand_write_oob: "
1720                       "Attempt to write past end of page\n");
1721                 return -EINVAL;
1722         }
1723
1724         chipnr = (int)(to >> chip->chip_shift);
1725         chip->select_chip(mtd, chipnr);
1726
1727         /* Shift to get page */
1728         page = (int)(to >> chip->page_shift);
1729
1730         /*
1731          * Reset the chip. Some chips (like the Toshiba TC5832DC found in one
1732          * of my DiskOnChip 2000 test units) will clear the whole data page too
1733          * if we don't do this. I have no clue why, but I seem to have 'fixed'
1734          * it in the doc2000 driver in August 1999.  dwmw2.
1735          */
1736         chip->cmdfunc(mtd, NAND_CMD_RESET, -1, -1);
1737
1738         /* Check, if it is write protected */
1739         if (nand_check_wp(mtd))
1740                 return -EROFS;
1741
1742         /* Invalidate the page cache, if we write to the cached page */
1743         if (page == chip->pagebuf)
1744                 chip->pagebuf = -1;
1745
1746         chip->oob_poi = chip->buffers.oobwbuf;
1747         memset(chip->oob_poi, 0xff, mtd->oobsize);
1748         nand_fill_oob(chip, ops->oobbuf, ops);
1749         status = chip->ecc.write_oob(mtd, chip, page & chip->pagemask);
1750         memset(chip->oob_poi, 0xff, mtd->oobsize);
1751
1752         if (status)
1753                 return status;
1754
1755         ops->retlen = ops->len;
1756
1757         return 0;
1758 }
1759
1760 /**
1761  * nand_write_oob - [MTD Interface] NAND write data and/or out-of-band
1762  * @mtd:        MTD device structure
1763  * @from:       offset to read from
1764  * @ops:        oob operation description structure
1765  */
1766 static int nand_write_oob(struct mtd_info *mtd, loff_t to,
1767                           struct mtd_oob_ops *ops)
1768 {
1769         void (*write_page)(struct mtd_info *mtd, struct nand_chip *chip,
1770                           const uint8_t *buf) = NULL;
1771         struct nand_chip *chip = mtd->priv;
1772         int ret = -ENOTSUPP;
1773
1774         ops->retlen = 0;
1775
1776         /* Do not allow writes past end of device */
1777         if ((to + ops->len) > mtd->size) {
1778                 DEBUG(MTD_DEBUG_LEVEL0, "nand_read_oob: "
1779                       "Attempt read beyond end of device\n");
1780                 return -EINVAL;
1781         }
1782
1783         nand_get_device(chip, mtd, FL_WRITING);
1784
1785         switch(ops->mode) {
1786         case MTD_OOB_PLACE:
1787         case MTD_OOB_AUTO:
1788                 break;
1789
1790         case MTD_OOB_RAW:
1791                 /* Replace the write_page algorithm temporary */
1792                 write_page = chip->ecc.write_page;
1793                 chip->ecc.write_page = nand_write_page_raw;
1794                 break;
1795
1796         default:
1797                 goto out;
1798         }
1799
1800         if (!ops->datbuf)
1801                 ret = nand_do_write_oob(mtd, to, ops);
1802         else
1803                 ret = nand_do_write_ops(mtd, to, ops);
1804
1805         if (unlikely(ops->mode == MTD_OOB_RAW))
1806                 chip->ecc.write_page = write_page;
1807  out:
1808         nand_release_device(mtd);
1809         return ret;
1810 }
1811
1812 /**
1813  * single_erease_cmd - [GENERIC] NAND standard block erase command function
1814  * @mtd:        MTD device structure
1815  * @page:       the page address of the block which will be erased
1816  *
1817  * Standard erase command for NAND chips
1818  */
1819 static void single_erase_cmd(struct mtd_info *mtd, int page)
1820 {
1821         struct nand_chip *chip = mtd->priv;
1822         /* Send commands to erase a block */
1823         chip->cmdfunc(mtd, NAND_CMD_ERASE1, -1, page);
1824         chip->cmdfunc(mtd, NAND_CMD_ERASE2, -1, -1);
1825 }
1826
1827 /**
1828  * multi_erease_cmd - [GENERIC] AND specific block erase command function
1829  * @mtd:        MTD device structure
1830  * @page:       the page address of the block which will be erased
1831  *
1832  * AND multi block erase command function
1833  * Erase 4 consecutive blocks
1834  */
1835 static void multi_erase_cmd(struct mtd_info *mtd, int page)
1836 {
1837         struct nand_chip *chip = mtd->priv;
1838         /* Send commands to erase a block */
1839         chip->cmdfunc(mtd, NAND_CMD_ERASE1, -1, page++);
1840         chip->cmdfunc(mtd, NAND_CMD_ERASE1, -1, page++);
1841         chip->cmdfunc(mtd, NAND_CMD_ERASE1, -1, page++);
1842         chip->cmdfunc(mtd, NAND_CMD_ERASE1, -1, page);
1843         chip->cmdfunc(mtd, NAND_CMD_ERASE2, -1, -1);
1844 }
1845
1846 /**
1847  * nand_erase - [MTD Interface] erase block(s)
1848  * @mtd:        MTD device structure
1849  * @instr:      erase instruction
1850  *
1851  * Erase one ore more blocks
1852  */
1853 static int nand_erase(struct mtd_info *mtd, struct erase_info *instr)
1854 {
1855         return nand_erase_nand(mtd, instr, 0);
1856 }
1857
1858 #define BBT_PAGE_MASK   0xffffff3f
1859 /**
1860  * nand_erase_nand - [Internal] erase block(s)
1861  * @mtd:        MTD device structure
1862  * @instr:      erase instruction
1863  * @allowbbt:   allow erasing the bbt area
1864  *
1865  * Erase one ore more blocks
1866  */
1867 int nand_erase_nand(struct mtd_info *mtd, struct erase_info *instr,
1868                     int allowbbt)
1869 {
1870         int page, len, status, pages_per_block, ret, chipnr;
1871         struct nand_chip *chip = mtd->priv;
1872         int rewrite_bbt[NAND_MAX_CHIPS]={0};
1873         unsigned int bbt_masked_page = 0xffffffff;
1874
1875         DEBUG(MTD_DEBUG_LEVEL3, "nand_erase: start = 0x%08x, len = %i\n",
1876               (unsigned int)instr->addr, (unsigned int)instr->len);
1877
1878         /* Start address must align on block boundary */
1879         if (instr->addr & ((1 << chip->phys_erase_shift) - 1)) {
1880                 DEBUG(MTD_DEBUG_LEVEL0, "nand_erase: Unaligned address\n");
1881                 return -EINVAL;
1882         }
1883
1884         /* Length must align on block boundary */
1885         if (instr->len & ((1 << chip->phys_erase_shift) - 1)) {
1886                 DEBUG(MTD_DEBUG_LEVEL0, "nand_erase: "
1887                       "Length not block aligned\n");
1888                 return -EINVAL;
1889         }
1890
1891         /* Do not allow erase past end of device */
1892         if ((instr->len + instr->addr) > mtd->size) {
1893                 DEBUG(MTD_DEBUG_LEVEL0, "nand_erase: "
1894                       "Erase past end of device\n");
1895                 return -EINVAL;
1896         }
1897
1898         instr->fail_addr = 0xffffffff;
1899
1900         /* Grab the lock and see if the device is available */
1901         nand_get_device(chip, mtd, FL_ERASING);
1902
1903         /* Shift to get first page */
1904         page = (int)(instr->addr >> chip->page_shift);
1905         chipnr = (int)(instr->addr >> chip->chip_shift);
1906
1907         /* Calculate pages in each block */
1908         pages_per_block = 1 << (chip->phys_erase_shift - chip->page_shift);
1909
1910         /* Select the NAND device */
1911         chip->select_chip(mtd, chipnr);
1912
1913         /* Check, if it is write protected */
1914         if (nand_check_wp(mtd)) {
1915                 DEBUG(MTD_DEBUG_LEVEL0, "nand_erase: "
1916                       "Device is write protected!!!\n");
1917                 instr->state = MTD_ERASE_FAILED;
1918                 goto erase_exit;
1919         }
1920
1921         /*
1922          * If BBT requires refresh, set the BBT page mask to see if the BBT
1923          * should be rewritten. Otherwise the mask is set to 0xffffffff which
1924          * can not be matched. This is also done when the bbt is actually
1925          * erased to avoid recusrsive updates
1926          */
1927         if (chip->options & BBT_AUTO_REFRESH && !allowbbt)
1928                 bbt_masked_page = chip->bbt_td->pages[chipnr] & BBT_PAGE_MASK;
1929
1930         /* Loop through the pages */
1931         len = instr->len;
1932
1933         instr->state = MTD_ERASING;
1934
1935         while (len) {
1936                 /*
1937                  * heck if we have a bad block, we do not erase bad blocks !
1938                  */
1939                 if (nand_block_checkbad(mtd, ((loff_t) page) <<
1940                                         chip->page_shift, 0, allowbbt)) {
1941                         printk(KERN_WARNING "nand_erase: attempt to erase a "
1942                                "bad block at page 0x%08x\n", page);
1943                         instr->state = MTD_ERASE_FAILED;
1944                         goto erase_exit;
1945                 }
1946
1947                 /*
1948                  * Invalidate the page cache, if we erase the block which
1949                  * contains the current cached page
1950                  */
1951                 if (page <= chip->pagebuf && chip->pagebuf <
1952                     (page + pages_per_block))
1953                         chip->pagebuf = -1;
1954
1955                 chip->erase_cmd(mtd, page & chip->pagemask);
1956
1957                 status = chip->waitfunc(mtd, chip);
1958
1959                 /*
1960                  * See if operation failed and additional status checks are
1961                  * available
1962                  */
1963                 if ((status & NAND_STATUS_FAIL) && (chip->errstat))
1964                         status = chip->errstat(mtd, chip, FL_ERASING,
1965                                                status, page);
1966
1967                 /* See if block erase succeeded */
1968                 if (status & NAND_STATUS_FAIL) {
1969                         DEBUG(MTD_DEBUG_LEVEL0, "nand_erase: "
1970                               "Failed erase, page 0x%08x\n", page);
1971                         instr->state = MTD_ERASE_FAILED;
1972                         instr->fail_addr = (page << chip->page_shift);
1973                         goto erase_exit;
1974                 }
1975
1976                 /*
1977                  * If BBT requires refresh, set the BBT rewrite flag to the
1978                  * page being erased
1979                  */
1980                 if (bbt_masked_page != 0xffffffff &&
1981                     (page & BBT_PAGE_MASK) == bbt_masked_page)
1982                             rewrite_bbt[chipnr] = (page << chip->page_shift);
1983
1984                 /* Increment page address and decrement length */
1985                 len -= (1 << chip->phys_erase_shift);
1986                 page += pages_per_block;
1987
1988                 /* Check, if we cross a chip boundary */
1989                 if (len && !(page & chip->pagemask)) {
1990                         chipnr++;
1991                         chip->select_chip(mtd, -1);
1992                         chip->select_chip(mtd, chipnr);
1993
1994                         /*
1995                          * If BBT requires refresh and BBT-PERCHIP, set the BBT
1996                          * page mask to see if this BBT should be rewritten
1997                          */
1998                         if (bbt_masked_page != 0xffffffff &&
1999                             (chip->bbt_td->options & NAND_BBT_PERCHIP))
2000                                 bbt_masked_page = chip->bbt_td->pages[chipnr] &
2001                                         BBT_PAGE_MASK;
2002                 }
2003         }
2004         instr->state = MTD_ERASE_DONE;
2005
2006  erase_exit:
2007
2008         ret = instr->state == MTD_ERASE_DONE ? 0 : -EIO;
2009         /* Do call back function */
2010         if (!ret)
2011                 mtd_erase_callback(instr);
2012
2013         /* Deselect and wake up anyone waiting on the device */
2014         nand_release_device(mtd);
2015
2016         /*
2017          * If BBT requires refresh and erase was successful, rewrite any
2018          * selected bad block tables
2019          */
2020         if (bbt_masked_page == 0xffffffff || ret)
2021                 return ret;
2022
2023         for (chipnr = 0; chipnr < chip->numchips; chipnr++) {
2024                 if (!rewrite_bbt[chipnr])
2025                         continue;
2026                 /* update the BBT for chip */
2027                 DEBUG(MTD_DEBUG_LEVEL0, "nand_erase_nand: nand_update_bbt "
2028                       "(%d:0x%0x 0x%0x)\n", chipnr, rewrite_bbt[chipnr],
2029                       chip->bbt_td->pages[chipnr]);
2030                 nand_update_bbt(mtd, rewrite_bbt[chipnr]);
2031         }
2032
2033         /* Return more or less happy */
2034         return ret;
2035 }
2036
2037 /**
2038  * nand_sync - [MTD Interface] sync
2039  * @mtd:        MTD device structure
2040  *
2041  * Sync is actually a wait for chip ready function
2042  */
2043 static void nand_sync(struct mtd_info *mtd)
2044 {
2045         struct nand_chip *chip = mtd->priv;
2046
2047         DEBUG(MTD_DEBUG_LEVEL3, "nand_sync: called\n");
2048
2049         /* Grab the lock and see if the device is available */
2050         nand_get_device(chip, mtd, FL_SYNCING);
2051         /* Release it and go back */
2052         nand_release_device(mtd);
2053 }
2054
2055 /**
2056  * nand_block_isbad - [MTD Interface] Check if block at offset is bad
2057  * @mtd:        MTD device structure
2058  * @ofs:        offset relative to mtd start
2059  */
2060 static int nand_block_isbad(struct mtd_info *mtd, loff_t offs)
2061 {
2062         /* Check for invalid offset */
2063         if (offs > mtd->size)
2064                 return -EINVAL;
2065
2066         return nand_block_checkbad(mtd, offs, 1, 0);
2067 }
2068
2069 /**
2070  * nand_block_markbad - [MTD Interface] Mark block at the given offset as bad
2071  * @mtd:        MTD device structure
2072  * @ofs:        offset relative to mtd start
2073  */
2074 static int nand_block_markbad(struct mtd_info *mtd, loff_t ofs)
2075 {
2076         struct nand_chip *chip = mtd->priv;
2077         int ret;
2078
2079         if ((ret = nand_block_isbad(mtd, ofs))) {
2080                 /* If it was bad already, return success and do nothing. */
2081                 if (ret > 0)
2082                         return 0;
2083                 return ret;
2084         }
2085
2086         return chip->block_markbad(mtd, ofs);
2087 }
2088
2089 /**
2090  * nand_suspend - [MTD Interface] Suspend the NAND flash
2091  * @mtd:        MTD device structure
2092  */
2093 static int nand_suspend(struct mtd_info *mtd)
2094 {
2095         struct nand_chip *chip = mtd->priv;
2096
2097         return nand_get_device(chip, mtd, FL_PM_SUSPENDED);
2098 }
2099
2100 /**
2101  * nand_resume - [MTD Interface] Resume the NAND flash
2102  * @mtd:        MTD device structure
2103  */
2104 static void nand_resume(struct mtd_info *mtd)
2105 {
2106         struct nand_chip *chip = mtd->priv;
2107
2108         if (chip->state == FL_PM_SUSPENDED)
2109                 nand_release_device(mtd);
2110         else
2111                 printk(KERN_ERR "nand_resume() called for a chip which is not "
2112                        "in suspended state\n");
2113 }
2114
2115 /*
2116  * Set default functions
2117  */
2118 static void nand_set_defaults(struct nand_chip *chip, int busw)
2119 {
2120         /* check for proper chip_delay setup, set 20us if not */
2121         if (!chip->chip_delay)
2122                 chip->chip_delay = 20;
2123
2124         /* check, if a user supplied command function given */
2125         if (chip->cmdfunc == NULL)
2126                 chip->cmdfunc = nand_command;
2127
2128         /* check, if a user supplied wait function given */
2129         if (chip->waitfunc == NULL)
2130                 chip->waitfunc = nand_wait;
2131
2132         if (!chip->select_chip)
2133                 chip->select_chip = nand_select_chip;
2134         if (!chip->read_byte)
2135                 chip->read_byte = busw ? nand_read_byte16 : nand_read_byte;
2136         if (!chip->read_word)
2137                 chip->read_word = nand_read_word;
2138         if (!chip->block_bad)
2139                 chip->block_bad = nand_block_bad;
2140         if (!chip->block_markbad)
2141                 chip->block_markbad = nand_default_block_markbad;
2142         if (!chip->write_buf)
2143                 chip->write_buf = busw ? nand_write_buf16 : nand_write_buf;
2144         if (!chip->read_buf)
2145                 chip->read_buf = busw ? nand_read_buf16 : nand_read_buf;
2146         if (!chip->verify_buf)
2147                 chip->verify_buf = busw ? nand_verify_buf16 : nand_verify_buf;
2148         if (!chip->scan_bbt)
2149                 chip->scan_bbt = nand_default_bbt;
2150
2151         if (!chip->controller) {
2152                 chip->controller = &chip->hwcontrol;
2153                 spin_lock_init(&chip->controller->lock);
2154                 init_waitqueue_head(&chip->controller->wq);
2155         }
2156
2157 }
2158
2159 /*
2160  * Get the flash and manufacturer id and lookup if the type is supported
2161  */
2162 static struct nand_flash_dev *nand_get_flash_type(struct mtd_info *mtd,
2163                                                   struct nand_chip *chip,
2164                                                   int busw, int *maf_id)
2165 {
2166         struct nand_flash_dev *type = NULL;
2167         int i, dev_id, maf_idx;
2168
2169         /* Select the device */
2170         chip->select_chip(mtd, 0);
2171
2172         /* Send the command for reading device ID */
2173         chip->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1);
2174
2175         /* Read manufacturer and device IDs */
2176         *maf_id = chip->read_byte(mtd);
2177         dev_id = chip->read_byte(mtd);
2178
2179         /* Lookup the flash id */
2180         for (i = 0; nand_flash_ids[i].name != NULL; i++) {
2181                 if (dev_id == nand_flash_ids[i].id) {
2182                         type =  &nand_flash_ids[i];
2183                         break;
2184                 }
2185         }
2186
2187         if (!type)
2188                 return ERR_PTR(-ENODEV);
2189
2190         if (!mtd->name)
2191                 mtd->name = type->name;
2192
2193         chip->chipsize = type->chipsize << 20;
2194
2195         /* Newer devices have all the information in additional id bytes */
2196         if (!type->pagesize) {
2197                 int extid;
2198                 /* The 3rd id byte contains non relevant data ATM */
2199                 extid = chip->read_byte(mtd);
2200                 /* The 4th id byte is the important one */
2201                 extid = chip->read_byte(mtd);
2202                 /* Calc pagesize */
2203                 mtd->writesize = 1024 << (extid & 0x3);
2204                 extid >>= 2;
2205                 /* Calc oobsize */
2206                 mtd->oobsize = (8 << (extid & 0x01)) * (mtd->writesize >> 9);
2207                 extid >>= 2;
2208                 /* Calc blocksize. Blocksize is multiples of 64KiB */
2209                 mtd->erasesize = (64 * 1024) << (extid & 0x03);
2210                 extid >>= 2;
2211                 /* Get buswidth information */
2212                 busw = (extid & 0x01) ? NAND_BUSWIDTH_16 : 0;
2213
2214         } else {
2215                 /*
2216                  * Old devices have chip data hardcoded in the device id table
2217                  */
2218                 mtd->erasesize = type->erasesize;
2219                 mtd->writesize = type->pagesize;
2220                 mtd->oobsize = mtd->writesize / 32;
2221                 busw = type->options & NAND_BUSWIDTH_16;
2222         }
2223
2224         /* Try to identify manufacturer */
2225         for (maf_idx = 0; nand_manuf_ids[maf_idx].id != 0x0; maf_id++) {
2226                 if (nand_manuf_ids[maf_idx].id == *maf_id)
2227                         break;
2228         }
2229
2230         /*
2231          * Check, if buswidth is correct. Hardware drivers should set
2232          * chip correct !
2233          */
2234         if (busw != (chip->options & NAND_BUSWIDTH_16)) {
2235                 printk(KERN_INFO "NAND device: Manufacturer ID:"
2236                        " 0x%02x, Chip ID: 0x%02x (%s %s)\n", *maf_id,
2237                        dev_id, nand_manuf_ids[maf_idx].name, mtd->name);
2238                 printk(KERN_WARNING "NAND bus width %d instead %d bit\n",
2239                        (chip->options & NAND_BUSWIDTH_16) ? 16 : 8,
2240                        busw ? 16 : 8);
2241                 return ERR_PTR(-EINVAL);
2242         }
2243
2244         /* Calculate the address shift from the page size */
2245         chip->page_shift = ffs(mtd->writesize) - 1;
2246         /* Convert chipsize to number of pages per chip -1. */
2247         chip->pagemask = (chip->chipsize >> chip->page_shift) - 1;
2248
2249         chip->bbt_erase_shift = chip->phys_erase_shift =
2250                 ffs(mtd->erasesize) - 1;
2251         chip->chip_shift = ffs(chip->chipsize) - 1;
2252
2253         /* Set the bad block position */
2254         chip->badblockpos = mtd->writesize > 512 ?
2255                 NAND_LARGE_BADBLOCK_POS : NAND_SMALL_BADBLOCK_POS;
2256
2257         /* Get chip options, preserve non chip based options */
2258         chip->options &= ~NAND_CHIPOPTIONS_MSK;
2259         chip->options |= type->options & NAND_CHIPOPTIONS_MSK;
2260
2261         /*
2262          * Set chip as a default. Board drivers can override it, if necessary
2263          */
2264         chip->options |= NAND_NO_AUTOINCR;
2265
2266         /* Check if chip is a not a samsung device. Do not clear the
2267          * options for chips which are not having an extended id.
2268          */
2269         if (*maf_id != NAND_MFR_SAMSUNG && !type->pagesize)
2270                 chip->options &= ~NAND_SAMSUNG_LP_OPTIONS;
2271
2272         /* Check for AND chips with 4 page planes */
2273         if (chip->options & NAND_4PAGE_ARRAY)
2274                 chip->erase_cmd = multi_erase_cmd;
2275         else
2276                 chip->erase_cmd = single_erase_cmd;
2277
2278         /* Do not replace user supplied command function ! */
2279         if (mtd->writesize > 512 && chip->cmdfunc == nand_command)
2280                 chip->cmdfunc = nand_command_lp;
2281
2282         printk(KERN_INFO "NAND device: Manufacturer ID:"
2283                " 0x%02x, Chip ID: 0x%02x (%s %s)\n", *maf_id, dev_id,
2284                nand_manuf_ids[maf_idx].name, type->name);
2285
2286         return type;
2287 }
2288
2289 /* module_text_address() isn't exported, and it's mostly a pointless
2290    test if this is a module _anyway_ -- they'd have to try _really_ hard
2291    to call us from in-kernel code if the core NAND support is modular. */
2292 #ifdef MODULE
2293 #define caller_is_module() (1)
2294 #else
2295 #define caller_is_module() \
2296         module_text_address((unsigned long)__builtin_return_address(0))
2297 #endif
2298
2299 /**
2300  * nand_scan - [NAND Interface] Scan for the NAND device
2301  * @mtd:        MTD device structure
2302  * @maxchips:   Number of chips to scan for
2303  *
2304  * This fills out all the uninitialized function pointers
2305  * with the defaults.
2306  * The flash ID is read and the mtd/chip structures are
2307  * filled with the appropriate values.
2308  * The mtd->owner field must be set to the module of the caller
2309  *
2310  */
2311 int nand_scan(struct mtd_info *mtd, int maxchips)
2312 {
2313         int i, busw, nand_maf_id;
2314         struct nand_chip *chip = mtd->priv;
2315         struct nand_flash_dev *type;
2316
2317         /* Many callers got this wrong, so check for it for a while... */
2318         if (!mtd->owner && caller_is_module()) {
2319                 printk(KERN_CRIT "nand_scan() called with NULL mtd->owner!\n");
2320                 BUG();
2321         }
2322
2323         /* Get buswidth to select the correct functions */
2324         busw = chip->options & NAND_BUSWIDTH_16;
2325         /* Set the default functions */
2326         nand_set_defaults(chip, busw);
2327
2328         /* Read the flash type */
2329         type = nand_get_flash_type(mtd, chip, busw, &nand_maf_id);
2330
2331         if (IS_ERR(type)) {
2332                 printk(KERN_WARNING "No NAND device found!!!\n");
2333                 chip->select_chip(mtd, -1);
2334                 return PTR_ERR(type);
2335         }
2336
2337         /* Check for a chip array */
2338         for (i = 1; i < maxchips; i++) {
2339                 chip->select_chip(mtd, i);
2340                 /* Send the command for reading device ID */
2341                 chip->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1);
2342                 /* Read manufacturer and device IDs */
2343                 if (nand_maf_id != chip->read_byte(mtd) ||
2344                     type->id != chip->read_byte(mtd))
2345                         break;
2346         }
2347         if (i > 1)
2348                 printk(KERN_INFO "%d NAND chips detected\n", i);
2349
2350         /* Store the number of chips and calc total size for mtd */
2351         chip->numchips = i;
2352         mtd->size = i * chip->chipsize;
2353
2354         /* Preset the internal oob write buffer */
2355         memset(chip->buffers.oobwbuf, 0xff, mtd->oobsize);
2356
2357         /*
2358          * If no default placement scheme is given, select an appropriate one
2359          */
2360         if (!chip->ecc.layout) {
2361                 switch (mtd->oobsize) {
2362                 case 8:
2363                         chip->ecc.layout = &nand_oob_8;
2364                         break;
2365                 case 16:
2366                         chip->ecc.layout = &nand_oob_16;
2367                         break;
2368                 case 64:
2369                         chip->ecc.layout = &nand_oob_64;
2370                         break;
2371                 default:
2372                         printk(KERN_WARNING "No oob scheme defined for "
2373                                "oobsize %d\n", mtd->oobsize);
2374                         BUG();
2375                 }
2376         }
2377
2378         /*
2379          * check ECC mode, default to software if 3byte/512byte hardware ECC is
2380          * selected and we have 256 byte pagesize fallback to software ECC
2381          */
2382         switch (chip->ecc.mode) {
2383         case NAND_ECC_HW:
2384                 /* Use standard hwecc read page function ? */
2385                 if (!chip->ecc.read_page)
2386                         chip->ecc.read_page = nand_read_page_hwecc;
2387                 if (!chip->ecc.write_page)
2388                         chip->ecc.write_page = nand_write_page_hwecc;
2389                 if (!chip->ecc.read_oob)
2390                         chip->ecc.read_oob = nand_read_oob_std;
2391                 if (!chip->ecc.write_oob)
2392                         chip->ecc.write_oob = nand_write_oob_std;
2393
2394         case NAND_ECC_HW_SYNDROME:
2395                 if (!chip->ecc.calculate || !chip->ecc.correct ||
2396                     !chip->ecc.hwctl) {
2397                         printk(KERN_WARNING "No ECC functions supplied, "
2398                                "Hardware ECC not possible\n");
2399                         BUG();
2400                 }
2401                 /* Use standard syndrome read/write page function ? */
2402                 if (!chip->ecc.read_page)
2403                         chip->ecc.read_page = nand_read_page_syndrome;
2404                 if (!chip->ecc.write_page)
2405                         chip->ecc.write_page = nand_write_page_syndrome;
2406                 if (!chip->ecc.read_oob)
2407                         chip->ecc.read_oob = nand_read_oob_syndrome;
2408                 if (!chip->ecc.write_oob)
2409                         chip->ecc.write_oob = nand_write_oob_syndrome;
2410
2411                 if (mtd->writesize >= chip->ecc.size)
2412                         break;
2413                 printk(KERN_WARNING "%d byte HW ECC not possible on "
2414                        "%d byte page size, fallback to SW ECC\n",
2415                        chip->ecc.size, mtd->writesize);
2416                 chip->ecc.mode = NAND_ECC_SOFT;
2417
2418         case NAND_ECC_SOFT:
2419                 chip->ecc.calculate = nand_calculate_ecc;
2420                 chip->ecc.correct = nand_correct_data;
2421                 chip->ecc.read_page = nand_read_page_swecc;
2422                 chip->ecc.write_page = nand_write_page_swecc;
2423                 chip->ecc.read_oob = nand_read_oob_std;
2424                 chip->ecc.write_oob = nand_write_oob_std;
2425                 chip->ecc.size = 256;
2426                 chip->ecc.bytes = 3;
2427                 break;
2428
2429         case NAND_ECC_NONE:
2430                 printk(KERN_WARNING "NAND_ECC_NONE selected by board driver. "
2431                        "This is not recommended !!\n");
2432                 chip->ecc.read_page = nand_read_page_raw;
2433                 chip->ecc.write_page = nand_write_page_raw;
2434                 chip->ecc.read_oob = nand_read_oob_std;
2435                 chip->ecc.write_oob = nand_write_oob_std;
2436                 chip->ecc.size = mtd->writesize;
2437                 chip->ecc.bytes = 0;
2438                 break;
2439         default:
2440                 printk(KERN_WARNING "Invalid NAND_ECC_MODE %d\n",
2441                        chip->ecc.mode);
2442                 BUG();
2443         }
2444
2445         /*
2446          * The number of bytes available for a client to place data into
2447          * the out of band area
2448          */
2449         chip->ecc.layout->oobavail = 0;
2450         for (i = 0; chip->ecc.layout->oobfree[i].length; i++)
2451                 chip->ecc.layout->oobavail +=
2452                         chip->ecc.layout->oobfree[i].length;
2453
2454         /*
2455          * Set the number of read / write steps for one page depending on ECC
2456          * mode
2457          */
2458         chip->ecc.steps = mtd->writesize / chip->ecc.size;
2459         if(chip->ecc.steps * chip->ecc.size != mtd->writesize) {
2460                 printk(KERN_WARNING "Invalid ecc parameters\n");
2461                 BUG();
2462         }
2463         chip->ecc.total = chip->ecc.steps * chip->ecc.bytes;
2464
2465         /* Initialize state */
2466         chip->state = FL_READY;
2467
2468         /* De-select the device */
2469         chip->select_chip(mtd, -1);
2470
2471         /* Invalidate the pagebuffer reference */
2472         chip->pagebuf = -1;
2473
2474         /* Fill in remaining MTD driver data */
2475         mtd->type = MTD_NANDFLASH;
2476         mtd->flags = MTD_CAP_NANDFLASH;
2477         mtd->ecctype = MTD_ECC_SW;
2478         mtd->erase = nand_erase;
2479         mtd->point = NULL;
2480         mtd->unpoint = NULL;
2481         mtd->read = nand_read;
2482         mtd->write = nand_write;
2483         mtd->read_oob = nand_read_oob;
2484         mtd->write_oob = nand_write_oob;
2485         mtd->sync = nand_sync;
2486         mtd->lock = NULL;
2487         mtd->unlock = NULL;
2488         mtd->suspend = nand_suspend;
2489         mtd->resume = nand_resume;
2490         mtd->block_isbad = nand_block_isbad;
2491         mtd->block_markbad = nand_block_markbad;
2492
2493         /* propagate ecc.layout to mtd_info */
2494         mtd->ecclayout = chip->ecc.layout;
2495
2496         /* Check, if we should skip the bad block table scan */
2497         if (chip->options & NAND_SKIP_BBTSCAN)
2498                 return 0;
2499
2500         /* Build bad block table */
2501         return chip->scan_bbt(mtd);
2502 }
2503
2504 /**
2505  * nand_release - [NAND Interface] Free resources held by the NAND device
2506  * @mtd:        MTD device structure
2507 */
2508 void nand_release(struct mtd_info *mtd)
2509 {
2510         struct nand_chip *chip = mtd->priv;
2511
2512 #ifdef CONFIG_MTD_PARTITIONS
2513         /* Deregister partitions */
2514         del_mtd_partitions(mtd);
2515 #endif
2516         /* Deregister the device */
2517         del_mtd_device(mtd);
2518
2519         /* Free bad block table memory */
2520         kfree(chip->bbt);
2521 }
2522
2523 EXPORT_SYMBOL_GPL(nand_scan);
2524 EXPORT_SYMBOL_GPL(nand_release);
2525
2526 static int __init nand_base_init(void)
2527 {
2528         led_trigger_register_simple("nand-disk", &nand_led_trigger);
2529         return 0;
2530 }
2531
2532 static void __exit nand_base_exit(void)
2533 {
2534         led_trigger_unregister_simple(nand_led_trigger);
2535 }
2536
2537 module_init(nand_base_init);
2538 module_exit(nand_base_exit);
2539
2540 MODULE_LICENSE("GPL");
2541 MODULE_AUTHOR("Steven J. Hill <sjhill@realitydiluted.com>, Thomas Gleixner <tglx@linutronix.de>");
2542 MODULE_DESCRIPTION("Generic NAND flash driver code");