linux-old/drivers/mtd/devices/doc2000.c
<<
>>
Prefs
   1
   2/*
   3 * Linux driver for Disk-On-Chip 2000 and Millennium
   4 * (c) 1999 Machine Vision Holdings, Inc.
   5 * (c) 1999, 2000 David Woodhouse <dwmw2@infradead.org>
   6 *
   7 * $Id: doc2000.c,v 1.50 2002/12/10 15:05:42 gleixner Exp $
   8 */
   9
  10#include <linux/kernel.h>
  11#include <linux/module.h>
  12#include <asm/errno.h>
  13#include <asm/io.h>
  14#include <asm/uaccess.h>
  15#include <linux/miscdevice.h>
  16#include <linux/pci.h>
  17#include <linux/delay.h>
  18#include <linux/slab.h>
  19#include <linux/sched.h>
  20#include <linux/init.h>
  21#include <linux/types.h>
  22
  23#include <linux/mtd/mtd.h>
  24#include <linux/mtd/nand.h>
  25#include <linux/mtd/doc2000.h>
  26
  27#define DOC_SUPPORT_2000
  28#define DOC_SUPPORT_MILLENNIUM
  29
  30#ifdef DOC_SUPPORT_2000
  31#define DoC_is_2000(doc) (doc->ChipID == DOC_ChipID_Doc2k)
  32#else
  33#define DoC_is_2000(doc) (0)
  34#endif
  35
  36#ifdef DOC_SUPPORT_MILLENNIUM
  37#define DoC_is_Millennium(doc) (doc->ChipID == DOC_ChipID_DocMil)
  38#else
  39#define DoC_is_Millennium(doc) (0)
  40#endif
  41
  42/* #define ECC_DEBUG */
  43
  44/* I have no idea why some DoC chips can not use memcpy_from|to_io().
  45 * This may be due to the different revisions of the ASIC controller built-in or
  46 * simplily a QA/Bug issue. Who knows ?? If you have trouble, please uncomment
  47 * this:
  48 #undef USE_MEMCPY
  49*/
  50
  51static int doc_read(struct mtd_info *mtd, loff_t from, size_t len,
  52                    size_t *retlen, u_char *buf);
  53static int doc_write(struct mtd_info *mtd, loff_t to, size_t len,
  54                     size_t *retlen, const u_char *buf);
  55static int doc_read_ecc(struct mtd_info *mtd, loff_t from, size_t len,
  56                        size_t *retlen, u_char *buf, u_char *eccbuf, int oobsel);
  57static int doc_write_ecc(struct mtd_info *mtd, loff_t to, size_t len,
  58                         size_t *retlen, const u_char *buf, u_char *eccbuf, int oobsel);
  59static int doc_read_oob(struct mtd_info *mtd, loff_t ofs, size_t len,
  60                        size_t *retlen, u_char *buf);
  61static int doc_write_oob(struct mtd_info *mtd, loff_t ofs, size_t len,
  62                         size_t *retlen, const u_char *buf);
  63static int doc_write_oob_nolock(struct mtd_info *mtd, loff_t ofs, size_t len,
  64                         size_t *retlen, const u_char *buf);
  65static int doc_erase (struct mtd_info *mtd, struct erase_info *instr);
  66
  67static struct mtd_info *doc2klist = NULL;
  68
  69/* Perform the required delay cycles by reading from the appropriate register */
  70static void DoC_Delay(struct DiskOnChip *doc, unsigned short cycles)
  71{
  72        volatile char dummy;
  73        int i;
  74        
  75        for (i = 0; i < cycles; i++) {
  76                if (DoC_is_Millennium(doc))
  77                        dummy = ReadDOC(doc->virtadr, NOP);
  78                else
  79                        dummy = ReadDOC(doc->virtadr, DOCStatus);
  80        }
  81        
  82}
  83
  84/* DOC_WaitReady: Wait for RDY line to be asserted by the flash chip */
  85static int _DoC_WaitReady(struct DiskOnChip *doc)
  86{
  87        unsigned long docptr = doc->virtadr;
  88        unsigned long timeo = jiffies + (HZ * 10);
  89
  90        DEBUG(MTD_DEBUG_LEVEL3,
  91              "_DoC_WaitReady called for out-of-line wait\n");
  92
  93        /* Out-of-line routine to wait for chip response */
  94        while (!(ReadDOC(docptr, CDSNControl) & CDSN_CTRL_FR_B)) {
  95                if (time_after(jiffies, timeo)) {
  96                        DEBUG(MTD_DEBUG_LEVEL2, "_DoC_WaitReady timed out.\n");
  97                        return -EIO;
  98                }
  99                udelay(1);
 100                cond_resched();
 101        }
 102
 103        return 0;
 104}
 105
 106static inline int DoC_WaitReady(struct DiskOnChip *doc)
 107{
 108        unsigned long docptr = doc->virtadr;
 109        /* This is inline, to optimise the common case, where it's ready instantly */
 110        int ret = 0;
 111
 112        /* 4 read form NOP register should be issued in prior to the read from CDSNControl
 113           see Software Requirement 11.4 item 2. */
 114        DoC_Delay(doc, 4);
 115
 116        if (!(ReadDOC(docptr, CDSNControl) & CDSN_CTRL_FR_B))
 117                /* Call the out-of-line routine to wait */
 118                ret = _DoC_WaitReady(doc);
 119
 120        /* issue 2 read from NOP register after reading from CDSNControl register
 121           see Software Requirement 11.4 item 2. */
 122        DoC_Delay(doc, 2);
 123
 124        return ret;
 125}
 126
 127/* DoC_Command: Send a flash command to the flash chip through the CDSN Slow IO register to
 128   bypass the internal pipeline. Each of 4 delay cycles (read from the NOP register) is
 129   required after writing to CDSN Control register, see Software Requirement 11.4 item 3. */
 130
 131static inline int DoC_Command(struct DiskOnChip *doc, unsigned char command,
 132                              unsigned char xtraflags)
 133{
 134        unsigned long docptr = doc->virtadr;
 135
 136        if (DoC_is_2000(doc))
 137                xtraflags |= CDSN_CTRL_FLASH_IO;
 138
 139        /* Assert the CLE (Command Latch Enable) line to the flash chip */
 140        WriteDOC(xtraflags | CDSN_CTRL_CLE | CDSN_CTRL_CE, docptr, CDSNControl);
 141        DoC_Delay(doc, 4);      /* Software requirement 11.4.3 for Millennium */
 142
 143        if (DoC_is_Millennium(doc))
 144                WriteDOC(command, docptr, CDSNSlowIO);
 145
 146        /* Send the command */
 147        WriteDOC_(command, docptr, doc->ioreg);
 148
 149        /* Lower the CLE line */
 150        WriteDOC(xtraflags | CDSN_CTRL_CE, docptr, CDSNControl);
 151        DoC_Delay(doc, 4);      /* Software requirement 11.4.3 for Millennium */
 152
 153        /* Wait for the chip to respond - Software requirement 11.4.1 (extended for any command) */
 154        return DoC_WaitReady(doc);
 155}
 156
 157/* DoC_Address: Set the current address for the flash chip through the CDSN Slow IO register to
 158   bypass the internal pipeline. Each of 4 delay cycles (read from the NOP register) is
 159   required after writing to CDSN Control register, see Software Requirement 11.4 item 3. */
 160
 161static int DoC_Address(struct DiskOnChip *doc, int numbytes, unsigned long ofs,
 162                       unsigned char xtraflags1, unsigned char xtraflags2)
 163{
 164        unsigned long docptr;
 165        int i;
 166
 167        docptr = doc->virtadr;
 168
 169        if (DoC_is_2000(doc))
 170                xtraflags1 |= CDSN_CTRL_FLASH_IO;
 171
 172        /* Assert the ALE (Address Latch Enable) line to the flash chip */
 173        WriteDOC(xtraflags1 | CDSN_CTRL_ALE | CDSN_CTRL_CE, docptr, CDSNControl);
 174
 175        DoC_Delay(doc, 4);      /* Software requirement 11.4.3 for Millennium */
 176
 177        /* Send the address */
 178        /* Devices with 256-byte page are addressed as:
 179           Column (bits 0-7), Page (bits 8-15, 16-23, 24-31)
 180           * there is no device on the market with page256
 181           and more than 24 bits.
 182           Devices with 512-byte page are addressed as:
 183           Column (bits 0-7), Page (bits 9-16, 17-24, 25-31)
 184           * 25-31 is sent only if the chip support it.
 185           * bit 8 changes the read command to be sent
 186           (NAND_CMD_READ0 or NAND_CMD_READ1).
 187         */
 188
 189        if (numbytes == ADDR_COLUMN || numbytes == ADDR_COLUMN_PAGE) {
 190                if (DoC_is_Millennium(doc))
 191                        WriteDOC(ofs & 0xff, docptr, CDSNSlowIO);
 192                WriteDOC_(ofs & 0xff, docptr, doc->ioreg);
 193        }
 194
 195        if (doc->page256) {
 196                ofs = ofs >> 8;
 197        } else {
 198                ofs = ofs >> 9;
 199        }
 200
 201        if (numbytes == ADDR_PAGE || numbytes == ADDR_COLUMN_PAGE) {
 202                for (i = 0; i < doc->pageadrlen; i++, ofs = ofs >> 8) {
 203                        if (DoC_is_Millennium(doc))
 204                                WriteDOC(ofs & 0xff, docptr, CDSNSlowIO);
 205                        WriteDOC_(ofs & 0xff, docptr, doc->ioreg);
 206                }
 207        }
 208
 209        DoC_Delay(doc, 2);      /* Needed for some slow flash chips. mf. */
 210        
 211        /* FIXME: The SlowIO's for millennium could be replaced by 
 212           a single WritePipeTerm here. mf. */
 213
 214        /* Lower the ALE line */
 215        WriteDOC(xtraflags1 | xtraflags2 | CDSN_CTRL_CE, docptr,
 216                 CDSNControl);
 217
 218        DoC_Delay(doc, 4);      /* Software requirement 11.4.3 for Millennium */
 219
 220        /* Wait for the chip to respond - Software requirement 11.4.1 */
 221        return DoC_WaitReady(doc);
 222}
 223
 224/* Read a buffer from DoC, taking care of Millennium odditys */
 225static void DoC_ReadBuf(struct DiskOnChip *doc, u_char * buf, int len)
 226{
 227        volatile int dummy;
 228        int modulus = 0xffff;
 229        unsigned long docptr;
 230        int i;
 231
 232        docptr = doc->virtadr;
 233
 234        if (len <= 0)
 235                return;
 236
 237        if (DoC_is_Millennium(doc)) {
 238                /* Read the data via the internal pipeline through CDSN IO register,
 239                   see Pipelined Read Operations 11.3 */
 240                dummy = ReadDOC(docptr, ReadPipeInit);
 241
 242                /* Millennium should use the LastDataRead register - Pipeline Reads */
 243                len--;
 244
 245                /* This is needed for correctly ECC calculation */
 246                modulus = 0xff;
 247        }
 248
 249        for (i = 0; i < len; i++)
 250                buf[i] = ReadDOC_(docptr, doc->ioreg + (i & modulus));
 251
 252        if (DoC_is_Millennium(doc)) {
 253                buf[i] = ReadDOC(docptr, LastDataRead);
 254        }
 255}
 256
 257/* Write a buffer to DoC, taking care of Millennium odditys */
 258static void DoC_WriteBuf(struct DiskOnChip *doc, const u_char * buf, int len)
 259{
 260        unsigned long docptr;
 261        int i;
 262
 263        docptr = doc->virtadr;
 264
 265        if (len <= 0)
 266                return;
 267
 268        for (i = 0; i < len; i++)
 269                WriteDOC_(buf[i], docptr, doc->ioreg + i);
 270
 271        if (DoC_is_Millennium(doc)) {
 272                WriteDOC(0x00, docptr, WritePipeTerm);
 273        }
 274}
 275
 276
 277/* DoC_SelectChip: Select a given flash chip within the current floor */
 278
 279static inline int DoC_SelectChip(struct DiskOnChip *doc, int chip)
 280{
 281        unsigned long docptr = doc->virtadr;
 282
 283        /* Software requirement 11.4.4 before writing DeviceSelect */
 284        /* Deassert the CE line to eliminate glitches on the FCE# outputs */
 285        WriteDOC(CDSN_CTRL_WP, docptr, CDSNControl);
 286        DoC_Delay(doc, 4);      /* Software requirement 11.4.3 for Millennium */
 287
 288        /* Select the individual flash chip requested */
 289        WriteDOC(chip, docptr, CDSNDeviceSelect);
 290        DoC_Delay(doc, 4);
 291
 292        /* Reassert the CE line */
 293        WriteDOC(CDSN_CTRL_CE | CDSN_CTRL_FLASH_IO | CDSN_CTRL_WP, docptr,
 294                 CDSNControl);
 295        DoC_Delay(doc, 4);      /* Software requirement 11.4.3 for Millennium */
 296
 297        /* Wait for it to be ready */
 298        return DoC_WaitReady(doc);
 299}
 300
 301/* DoC_SelectFloor: Select a given floor (bank of flash chips) */
 302
 303static inline int DoC_SelectFloor(struct DiskOnChip *doc, int floor)
 304{
 305        unsigned long docptr = doc->virtadr;
 306
 307        /* Select the floor (bank) of chips required */
 308        WriteDOC(floor, docptr, FloorSelect);
 309
 310        /* Wait for the chip to be ready */
 311        return DoC_WaitReady(doc);
 312}
 313
 314/* DoC_IdentChip: Identify a given NAND chip given {floor,chip} */
 315
 316static int DoC_IdentChip(struct DiskOnChip *doc, int floor, int chip)
 317{
 318        int mfr, id, i, j;
 319        volatile char dummy;
 320
 321        /* Page in the required floor/chip */
 322        DoC_SelectFloor(doc, floor);
 323        DoC_SelectChip(doc, chip);
 324
 325        /* Reset the chip */
 326        if (DoC_Command(doc, NAND_CMD_RESET, CDSN_CTRL_WP)) {
 327                DEBUG(MTD_DEBUG_LEVEL2,
 328                      "DoC_Command (reset) for %d,%d returned true\n",
 329                      floor, chip);
 330                return 0;
 331        }
 332
 333
 334        /* Read the NAND chip ID: 1. Send ReadID command */
 335        if (DoC_Command(doc, NAND_CMD_READID, CDSN_CTRL_WP)) {
 336                DEBUG(MTD_DEBUG_LEVEL2,
 337                      "DoC_Command (ReadID) for %d,%d returned true\n",
 338                      floor, chip);
 339                return 0;
 340        }
 341
 342        /* Read the NAND chip ID: 2. Send address byte zero */
 343        DoC_Address(doc, ADDR_COLUMN, 0, CDSN_CTRL_WP, 0);
 344
 345        /* Read the manufacturer and device id codes from the device */
 346
 347        /* CDSN Slow IO register see Software Requirement 11.4 item 5. */
 348        dummy = ReadDOC(doc->virtadr, CDSNSlowIO);
 349        DoC_Delay(doc, 2);
 350        mfr = ReadDOC_(doc->virtadr, doc->ioreg);
 351
 352        /* CDSN Slow IO register see Software Requirement 11.4 item 5. */
 353        dummy = ReadDOC(doc->virtadr, CDSNSlowIO);
 354        DoC_Delay(doc, 2);
 355        id = ReadDOC_(doc->virtadr, doc->ioreg);
 356
 357        /* No response - return failure */
 358        if (mfr == 0xff || mfr == 0)
 359                return 0;
 360
 361        /* Check it's the same as the first chip we identified. 
 362         * M-Systems say that any given DiskOnChip device should only
 363         * contain _one_ type of flash part, although that's not a 
 364         * hardware restriction. */
 365        if (doc->mfr) {
 366                if (doc->mfr == mfr && doc->id == id)
 367                        return 1;       /* This is another the same the first */
 368                else
 369                        printk(KERN_WARNING
 370                               "Flash chip at floor %d, chip %d is different:\n",
 371                               floor, chip);
 372        }
 373
 374        /* Print and store the manufacturer and ID codes. */
 375        for (i = 0; nand_flash_ids[i].name != NULL; i++) {
 376                if (id == nand_flash_ids[i].id) {
 377                        /* Try to identify manufacturer */
 378                        for (j = 0; nand_manuf_ids[j].id != 0x0; j++) {
 379                                if (nand_manuf_ids[j].id == mfr)
 380                                        break;
 381                        }       
 382                        printk(KERN_INFO
 383                               "Flash chip found: Manufacturer ID: %2.2X, "
 384                               "Chip ID: %2.2X (%s:%s)\n", mfr, id,
 385                               nand_manuf_ids[j].name, nand_flash_ids[i].name);
 386                        if (!doc->mfr) {
 387                                doc->mfr = mfr;
 388                                doc->id = id;
 389                                doc->chipshift =
 390                                    nand_flash_ids[i].chipshift;
 391                                doc->page256 = nand_flash_ids[i].page256;
 392                                doc->pageadrlen =
 393                                    nand_flash_ids[i].chipshift > 25 ? 3 : 2;
 394                                doc->erasesize =
 395                                    nand_flash_ids[i].erasesize;
 396                                return 1;
 397                        }
 398                        return 0;
 399                }
 400        }
 401
 402
 403        /* We haven't fully identified the chip. Print as much as we know. */
 404        printk(KERN_WARNING "Unknown flash chip found: %2.2X %2.2X\n",
 405               id, mfr);
 406
 407        printk(KERN_WARNING "Please report to dwmw2@infradead.org\n");
 408        return 0;
 409}
 410
 411/* DoC_ScanChips: Find all NAND chips present in a DiskOnChip, and identify them */
 412
 413static void DoC_ScanChips(struct DiskOnChip *this)
 414{
 415        int floor, chip;
 416        int numchips[MAX_FLOORS];
 417        int maxchips = MAX_CHIPS;
 418        int ret = 1;
 419
 420        this->numchips = 0;
 421        this->mfr = 0;
 422        this->id = 0;
 423
 424        if (DoC_is_Millennium(this))
 425                maxchips = MAX_CHIPS_MIL;
 426
 427        /* For each floor, find the number of valid chips it contains */
 428        for (floor = 0; floor < MAX_FLOORS; floor++) {
 429                ret = 1;
 430                numchips[floor] = 0;
 431                for (chip = 0; chip < maxchips && ret != 0; chip++) {
 432
 433                        ret = DoC_IdentChip(this, floor, chip);
 434                        if (ret) {
 435                                numchips[floor]++;
 436                                this->numchips++;
 437                        }
 438                }
 439        }
 440
 441        /* If there are none at all that we recognise, bail */
 442        if (!this->numchips) {
 443                printk(KERN_NOTICE "No flash chips recognised.\n");
 444                return;
 445        }
 446
 447        /* Allocate an array to hold the information for each chip */
 448        this->chips = kmalloc(sizeof(struct Nand) * this->numchips, GFP_KERNEL);
 449        if (!this->chips) {
 450                printk(KERN_NOTICE "No memory for allocating chip info structures\n");
 451                return;
 452        }
 453
 454        ret = 0;
 455
 456        /* Fill out the chip array with {floor, chipno} for each 
 457         * detected chip in the device. */
 458        for (floor = 0; floor < MAX_FLOORS; floor++) {
 459                for (chip = 0; chip < numchips[floor]; chip++) {
 460                        this->chips[ret].floor = floor;
 461                        this->chips[ret].chip = chip;
 462                        this->chips[ret].curadr = 0;
 463                        this->chips[ret].curmode = 0x50;
 464                        ret++;
 465                }
 466        }
 467
 468        /* Calculate and print the total size of the device */
 469        this->totlen = this->numchips * (1 << this->chipshift);
 470
 471        printk(KERN_INFO "%d flash chips found. Total DiskOnChip size: %ld MiB\n",
 472               this->numchips, this->totlen >> 20);
 473}
 474
 475static int DoC2k_is_alias(struct DiskOnChip *doc1, struct DiskOnChip *doc2)
 476{
 477        int tmp1, tmp2, retval;
 478        if (doc1->physadr == doc2->physadr)
 479                return 1;
 480
 481        /* Use the alias resolution register which was set aside for this
 482         * purpose. If it's value is the same on both chips, they might
 483         * be the same chip, and we write to one and check for a change in
 484         * the other. It's unclear if this register is usuable in the
 485         * DoC 2000 (it's in the Millennium docs), but it seems to work. */
 486        tmp1 = ReadDOC(doc1->virtadr, AliasResolution);
 487        tmp2 = ReadDOC(doc2->virtadr, AliasResolution);
 488        if (tmp1 != tmp2)
 489                return 0;
 490
 491        WriteDOC((tmp1 + 1) % 0xff, doc1->virtadr, AliasResolution);
 492        tmp2 = ReadDOC(doc2->virtadr, AliasResolution);
 493        if (tmp2 == (tmp1 + 1) % 0xff)
 494                retval = 1;
 495        else
 496                retval = 0;
 497
 498        /* Restore register contents.  May not be necessary, but do it just to
 499         * be safe. */
 500        WriteDOC(tmp1, doc1->virtadr, AliasResolution);
 501
 502        return retval;
 503}
 504
 505static const char im_name[] = "DoC2k_init";
 506
 507/* This routine is made available to other mtd code via
 508 * inter_module_register.  It must only be accessed through
 509 * inter_module_get which will bump the use count of this module.  The
 510 * addresses passed back in mtd are valid as long as the use count of
 511 * this module is non-zero, i.e. between inter_module_get and
 512 * inter_module_put.  Keith Owens <kaos@ocs.com.au> 29 Oct 2000.
 513 */
 514static void DoC2k_init(struct mtd_info *mtd)
 515{
 516        struct DiskOnChip *this = (struct DiskOnChip *) mtd->priv;
 517        struct DiskOnChip *old = NULL;
 518
 519        /* We must avoid being called twice for the same device. */
 520
 521        if (doc2klist)
 522                old = (struct DiskOnChip *) doc2klist->priv;
 523
 524        while (old) {
 525                if (DoC2k_is_alias(old, this)) {
 526                        printk(KERN_NOTICE
 527                               "Ignoring DiskOnChip 2000 at 0x%lX - already configured\n",
 528                               this->physadr);
 529                        iounmap((void *) this->virtadr);
 530                        kfree(mtd);
 531                        return;
 532                }
 533                if (old->nextdoc)
 534                        old = (struct DiskOnChip *) old->nextdoc->priv;
 535                else
 536                        old = NULL;
 537        }
 538
 539
 540        switch (this->ChipID) {
 541        case DOC_ChipID_Doc2k:
 542                mtd->name = "DiskOnChip 2000";
 543                this->ioreg = DoC_2k_CDSN_IO;
 544                break;
 545        case DOC_ChipID_DocMil:
 546                mtd->name = "DiskOnChip Millennium";
 547                this->ioreg = DoC_Mil_CDSN_IO;
 548                break;
 549        }
 550
 551        printk(KERN_NOTICE "%s found at address 0x%lX\n", mtd->name,
 552               this->physadr);
 553
 554        mtd->type = MTD_NANDFLASH;
 555        mtd->flags = MTD_CAP_NANDFLASH;
 556        mtd->size = 0;
 557        mtd->erasesize = 0;
 558        mtd->oobblock = 512;
 559        mtd->oobsize = 16;
 560        mtd->module = THIS_MODULE;
 561        mtd->erase = doc_erase;
 562        mtd->point = NULL;
 563        mtd->unpoint = NULL;
 564        mtd->read = doc_read;
 565        mtd->write = doc_write;
 566        mtd->read_ecc = doc_read_ecc;
 567        mtd->write_ecc = doc_write_ecc;
 568        mtd->read_oob = doc_read_oob;
 569        mtd->write_oob = doc_write_oob;
 570        mtd->sync = NULL;
 571
 572        this->totlen = 0;
 573        this->numchips = 0;
 574
 575        this->curfloor = -1;
 576        this->curchip = -1;
 577        init_MUTEX(&this->lock);
 578
 579        /* Ident all the chips present. */
 580        DoC_ScanChips(this);
 581
 582        if (!this->totlen) {
 583                kfree(mtd);
 584                iounmap((void *) this->virtadr);
 585        } else {
 586                this->nextdoc = doc2klist;
 587                doc2klist = mtd;
 588                mtd->size = this->totlen;
 589                mtd->erasesize = this->erasesize;
 590                add_mtd_device(mtd);
 591                return;
 592        }
 593}
 594
 595static int doc_read(struct mtd_info *mtd, loff_t from, size_t len,
 596                    size_t * retlen, u_char * buf)
 597{
 598        /* Just a special case of doc_read_ecc */
 599        return doc_read_ecc(mtd, from, len, retlen, buf, NULL, 0);
 600}
 601
 602static int doc_read_ecc(struct mtd_info *mtd, loff_t from, size_t len,
 603                        size_t * retlen, u_char * buf, u_char * eccbuf, int oobsel)
 604{
 605        struct DiskOnChip *this = (struct DiskOnChip *) mtd->priv;
 606        unsigned long docptr;
 607        struct Nand *mychip;
 608        unsigned char syndrome[6];
 609        volatile char dummy;
 610        int i, len256 = 0, ret=0;
 611
 612        docptr = this->virtadr;
 613
 614        /* Don't allow read past end of device */
 615        if (from >= this->totlen)
 616                return -EINVAL;
 617
 618        down(&this->lock);
 619
 620        /* Don't allow a single read to cross a 512-byte block boundary */
 621        if (from + len > ((from | 0x1ff) + 1))
 622                len = ((from | 0x1ff) + 1) - from;
 623
 624        /* The ECC will not be calculated correctly if less than 512 is read */
 625        if (len != 0x200 && eccbuf)
 626                printk(KERN_WARNING
 627                       "ECC needs a full sector read (adr: %lx size %lx)\n",
 628                       (long) from, (long) len);
 629
 630        /* printk("DoC_Read (adr: %lx size %lx)\n", (long) from, (long) len); */
 631
 632
 633        /* Find the chip which is to be used and select it */
 634        mychip = &this->chips[from >> (this->chipshift)];
 635
 636        if (this->curfloor != mychip->floor) {
 637                DoC_SelectFloor(this, mychip->floor);
 638                DoC_SelectChip(this, mychip->chip);
 639        } else if (this->curchip != mychip->chip) {
 640                DoC_SelectChip(this, mychip->chip);
 641        }
 642
 643        this->curfloor = mychip->floor;
 644        this->curchip = mychip->chip;
 645
 646        DoC_Command(this,
 647                    (!this->page256
 648                     && (from & 0x100)) ? NAND_CMD_READ1 : NAND_CMD_READ0,
 649                    CDSN_CTRL_WP);
 650        DoC_Address(this, ADDR_COLUMN_PAGE, from, CDSN_CTRL_WP,
 651                    CDSN_CTRL_ECC_IO);
 652
 653        if (eccbuf) {
 654                /* Prime the ECC engine */
 655                WriteDOC(DOC_ECC_RESET, docptr, ECCConf);
 656                WriteDOC(DOC_ECC_EN, docptr, ECCConf);
 657        } else {
 658                /* disable the ECC engine */
 659                WriteDOC(DOC_ECC_RESET, docptr, ECCConf);
 660                WriteDOC(DOC_ECC_DIS, docptr, ECCConf);
 661        }
 662
 663        /* treat crossing 256-byte sector for 2M x 8bits devices */
 664        if (this->page256 && from + len > (from | 0xff) + 1) {
 665                len256 = (from | 0xff) + 1 - from;
 666                DoC_ReadBuf(this, buf, len256);
 667
 668                DoC_Command(this, NAND_CMD_READ0, CDSN_CTRL_WP);
 669                DoC_Address(this, ADDR_COLUMN_PAGE, from + len256,
 670                            CDSN_CTRL_WP, CDSN_CTRL_ECC_IO);
 671        }
 672
 673        DoC_ReadBuf(this, &buf[len256], len - len256);
 674
 675        /* Let the caller know we completed it */
 676        *retlen = len;
 677
 678        if (eccbuf) {
 679                /* Read the ECC data through the DiskOnChip ECC logic */
 680                /* Note: this will work even with 2M x 8bit devices as   */
 681                /*       they have 8 bytes of OOB per 256 page. mf.      */
 682                DoC_ReadBuf(this, eccbuf, 6);
 683
 684                /* Flush the pipeline */
 685                if (DoC_is_Millennium(this)) {
 686                        dummy = ReadDOC(docptr, ECCConf);
 687                        dummy = ReadDOC(docptr, ECCConf);
 688                        i = ReadDOC(docptr, ECCConf);
 689                } else {
 690                        dummy = ReadDOC(docptr, 2k_ECCStatus);
 691                        dummy = ReadDOC(docptr, 2k_ECCStatus);
 692                        i = ReadDOC(docptr, 2k_ECCStatus);
 693                }
 694
 695                /* Check the ECC Status */
 696                if (i & 0x80) {
 697                        int nb_errors;
 698                        /* There was an ECC error */
 699#ifdef ECC_DEBUG
 700                        printk(KERN_ERR "DiskOnChip ECC Error: Read at %lx\n", (long)from);
 701#endif
 702                        /* Read the ECC syndrom through the DiskOnChip ECC logic.
 703                           These syndrome will be all ZERO when there is no error */
 704                        for (i = 0; i < 6; i++) {
 705                                syndrome[i] =
 706                                    ReadDOC(docptr, ECCSyndrome0 + i);
 707                        }
 708                        nb_errors = doc_decode_ecc(buf, syndrome);
 709
 710#ifdef ECC_DEBUG
 711                        printk(KERN_ERR "Errors corrected: %x\n", nb_errors);
 712#endif
 713                        if (nb_errors < 0) {
 714                                /* We return error, but have actually done the read. Not that
 715                                   this can be told to user-space, via sys_read(), but at least
 716                                   MTD-aware stuff can know about it by checking *retlen */
 717                                ret = -EIO;
 718                        }
 719                }
 720
 721#ifdef PSYCHO_DEBUG
 722                printk(KERN_DEBUG "ECC DATA at %lxB: %2.2X %2.2X %2.2X %2.2X %2.2X %2.2X\n",
 723                             (long)from, eccbuf[0], eccbuf[1], eccbuf[2],
 724                             eccbuf[3], eccbuf[4], eccbuf[5]);
 725#endif
 726                
 727                /* disable the ECC engine */
 728                WriteDOC(DOC_ECC_DIS, docptr , ECCConf);
 729        }
 730
 731        /* according to 11.4.1, we need to wait for the busy line 
 732         * drop if we read to the end of the page.  */
 733        if(0 == ((from + *retlen) & 0x1ff))
 734        {
 735            DoC_WaitReady(this);
 736        }
 737
 738        up(&this->lock);
 739
 740        return ret;
 741}
 742
 743static int doc_write(struct mtd_info *mtd, loff_t to, size_t len,
 744                     size_t * retlen, const u_char * buf)
 745{
 746        char eccbuf[6];
 747        return doc_write_ecc(mtd, to, len, retlen, buf, eccbuf, 0);
 748}
 749
 750static int doc_write_ecc(struct mtd_info *mtd, loff_t to, size_t len,
 751                         size_t * retlen, const u_char * buf,
 752                         u_char * eccbuf, int oobsel)
 753{
 754        struct DiskOnChip *this = (struct DiskOnChip *) mtd->priv;
 755        int di; /* Yes, DI is a hangover from when I was disassembling the binary driver */
 756        unsigned long docptr;
 757        volatile char dummy;
 758        int len256 = 0;
 759        struct Nand *mychip;
 760
 761        docptr = this->virtadr;
 762
 763        /* Don't allow write past end of device */
 764        if (to >= this->totlen)
 765                return -EINVAL;
 766
 767        down(&this->lock);
 768
 769        /* Don't allow a single write to cross a 512-byte block boundary */
 770        if (to + len > ((to | 0x1ff) + 1))
 771                len = ((to | 0x1ff) + 1) - to;
 772
 773        /* The ECC will not be calculated correctly if less than 512 is written */
 774        if (len != 0x200 && eccbuf)
 775                printk(KERN_WARNING
 776                       "ECC needs a full sector write (adr: %lx size %lx)\n",
 777                       (long) to, (long) len);
 778
 779        /* printk("DoC_Write (adr: %lx size %lx)\n", (long) to, (long) len); */
 780
 781        /* Find the chip which is to be used and select it */
 782        mychip = &this->chips[to >> (this->chipshift)];
 783
 784        if (this->curfloor != mychip->floor) {
 785                DoC_SelectFloor(this, mychip->floor);
 786                DoC_SelectChip(this, mychip->chip);
 787        } else if (this->curchip != mychip->chip) {
 788                DoC_SelectChip(this, mychip->chip);
 789        }
 790
 791        this->curfloor = mychip->floor;
 792        this->curchip = mychip->chip;
 793
 794        /* Set device to main plane of flash */
 795        DoC_Command(this, NAND_CMD_RESET, CDSN_CTRL_WP);
 796        DoC_Command(this,
 797                    (!this->page256
 798                     && (to & 0x100)) ? NAND_CMD_READ1 : NAND_CMD_READ0,
 799                    CDSN_CTRL_WP);
 800
 801        DoC_Command(this, NAND_CMD_SEQIN, 0);
 802        DoC_Address(this, ADDR_COLUMN_PAGE, to, 0, CDSN_CTRL_ECC_IO);
 803
 804        if (eccbuf) {
 805                /* Prime the ECC engine */
 806                WriteDOC(DOC_ECC_RESET, docptr, ECCConf);
 807                WriteDOC(DOC_ECC_EN | DOC_ECC_RW, docptr, ECCConf);
 808        } else {
 809                /* disable the ECC engine */
 810                WriteDOC(DOC_ECC_RESET, docptr, ECCConf);
 811                WriteDOC(DOC_ECC_DIS, docptr, ECCConf);
 812        }
 813
 814        /* treat crossing 256-byte sector for 2M x 8bits devices */
 815        if (this->page256 && to + len > (to | 0xff) + 1) {
 816                len256 = (to | 0xff) + 1 - to;
 817                DoC_WriteBuf(this, buf, len256);
 818
 819                DoC_Command(this, NAND_CMD_PAGEPROG, 0);
 820
 821                DoC_Command(this, NAND_CMD_STATUS, CDSN_CTRL_WP);
 822                /* There's an implicit DoC_WaitReady() in DoC_Command */
 823
 824                dummy = ReadDOC(docptr, CDSNSlowIO);
 825                DoC_Delay(this, 2);
 826
 827                if (ReadDOC_(docptr, this->ioreg) & 1) {
 828                        printk(KERN_ERR "Error programming flash\n");
 829                        /* Error in programming */
 830                        *retlen = 0;
 831                        up(&this->lock);
 832                        return -EIO;
 833                }
 834
 835                DoC_Command(this, NAND_CMD_SEQIN, 0);
 836                DoC_Address(this, ADDR_COLUMN_PAGE, to + len256, 0,
 837                            CDSN_CTRL_ECC_IO);
 838        }
 839
 840        DoC_WriteBuf(this, &buf[len256], len - len256);
 841
 842        if (eccbuf) {
 843                WriteDOC(CDSN_CTRL_ECC_IO | CDSN_CTRL_CE, docptr,
 844                         CDSNControl);
 845
 846                if (DoC_is_Millennium(this)) {
 847                        WriteDOC(0, docptr, NOP);
 848                        WriteDOC(0, docptr, NOP);
 849                        WriteDOC(0, docptr, NOP);
 850                } else {
 851                        WriteDOC_(0, docptr, this->ioreg);
 852                        WriteDOC_(0, docptr, this->ioreg);
 853                        WriteDOC_(0, docptr, this->ioreg);
 854                }
 855
 856                /* Read the ECC data through the DiskOnChip ECC logic */
 857                for (di = 0; di < 6; di++) {
 858                        eccbuf[di] = ReadDOC(docptr, ECCSyndrome0 + di);
 859                }
 860
 861                /* Reset the ECC engine */
 862                WriteDOC(DOC_ECC_DIS, docptr, ECCConf);
 863
 864#ifdef PSYCHO_DEBUG
 865                printk
 866                    ("OOB data at %lx is %2.2X %2.2X %2.2X %2.2X %2.2X %2.2X\n",
 867                     (long) to, eccbuf[0], eccbuf[1], eccbuf[2], eccbuf[3],
 868                     eccbuf[4], eccbuf[5]);
 869#endif
 870        }
 871
 872        DoC_Command(this, NAND_CMD_PAGEPROG, 0);
 873
 874        DoC_Command(this, NAND_CMD_STATUS, CDSN_CTRL_WP);
 875        /* There's an implicit DoC_WaitReady() in DoC_Command */
 876
 877        dummy = ReadDOC(docptr, CDSNSlowIO);
 878        DoC_Delay(this, 2);
 879
 880        if (ReadDOC_(docptr, this->ioreg) & 1) {
 881                printk(KERN_ERR "Error programming flash\n");
 882                /* Error in programming */
 883                *retlen = 0;
 884                up(&this->lock);
 885                return -EIO;
 886        }
 887
 888        /* Let the caller know we completed it */
 889        *retlen = len;
 890                
 891        if (eccbuf) {
 892                unsigned char x[8];
 893                size_t dummy;
 894                int ret;
 895
 896                /* Write the ECC data to flash */
 897                for (di=0; di<6; di++)
 898                        x[di] = eccbuf[di];
 899                
 900                x[6]=0x55;
 901                x[7]=0x55;
 902                
 903                ret = doc_write_oob_nolock(mtd, to, 8, &dummy, x);
 904                up(&this->lock);
 905                return ret;
 906        }
 907        up(&this->lock);
 908        return 0;
 909}
 910
 911static int doc_read_oob(struct mtd_info *mtd, loff_t ofs, size_t len,
 912                        size_t * retlen, u_char * buf)
 913{
 914        struct DiskOnChip *this = (struct DiskOnChip *) mtd->priv;
 915        int len256 = 0, ret;
 916        unsigned long docptr;
 917        struct Nand *mychip;
 918
 919        down(&this->lock);
 920
 921        docptr = this->virtadr;
 922
 923        mychip = &this->chips[ofs >> this->chipshift];
 924
 925        if (this->curfloor != mychip->floor) {
 926                DoC_SelectFloor(this, mychip->floor);
 927                DoC_SelectChip(this, mychip->chip);
 928        } else if (this->curchip != mychip->chip) {
 929                DoC_SelectChip(this, mychip->chip);
 930        }
 931        this->curfloor = mychip->floor;
 932        this->curchip = mychip->chip;
 933
 934        /* update address for 2M x 8bit devices. OOB starts on the second */
 935        /* page to maintain compatibility with doc_read_ecc. */
 936        if (this->page256) {
 937                if (!(ofs & 0x8))
 938                        ofs += 0x100;
 939                else
 940                        ofs -= 0x8;
 941        }
 942
 943        DoC_Command(this, NAND_CMD_READOOB, CDSN_CTRL_WP);
 944        DoC_Address(this, ADDR_COLUMN_PAGE, ofs, CDSN_CTRL_WP, 0);
 945
 946        /* treat crossing 8-byte OOB data for 2M x 8bit devices */
 947        /* Note: datasheet says it should automaticaly wrap to the */
 948        /*       next OOB block, but it didn't work here. mf.      */
 949        if (this->page256 && ofs + len > (ofs | 0x7) + 1) {
 950                len256 = (ofs | 0x7) + 1 - ofs;
 951                DoC_ReadBuf(this, buf, len256);
 952
 953                DoC_Command(this, NAND_CMD_READOOB, CDSN_CTRL_WP);
 954                DoC_Address(this, ADDR_COLUMN_PAGE, ofs & (~0x1ff),
 955                            CDSN_CTRL_WP, 0);
 956        }
 957
 958        DoC_ReadBuf(this, &buf[len256], len - len256);
 959
 960        *retlen = len;
 961        /* Reading the full OOB data drops us off of the end of the page,
 962         * causing the flash device to go into busy mode, so we need
 963         * to wait until ready 11.4.1 and Toshiba TC58256FT docs */
 964        
 965        ret = DoC_WaitReady(this);
 966
 967        up(&this->lock);
 968        return ret;
 969
 970}
 971
 972static int doc_write_oob_nolock(struct mtd_info *mtd, loff_t ofs, size_t len,
 973                                size_t * retlen, const u_char * buf)
 974{
 975        struct DiskOnChip *this = (struct DiskOnChip *) mtd->priv;
 976        int len256 = 0;
 977        unsigned long docptr = this->virtadr;
 978        struct Nand *mychip = &this->chips[ofs >> this->chipshift];
 979        volatile int dummy;
 980
 981        //      printk("doc_write_oob(%lx, %d): %2.2X %2.2X %2.2X %2.2X ... %2.2X %2.2X .. %2.2X %2.2X\n",(long)ofs, len,
 982        //   buf[0], buf[1], buf[2], buf[3], buf[8], buf[9], buf[14],buf[15]);
 983
 984        /* Find the chip which is to be used and select it */
 985        if (this->curfloor != mychip->floor) {
 986                DoC_SelectFloor(this, mychip->floor);
 987                DoC_SelectChip(this, mychip->chip);
 988        } else if (this->curchip != mychip->chip) {
 989                DoC_SelectChip(this, mychip->chip);
 990        }
 991        this->curfloor = mychip->floor;
 992        this->curchip = mychip->chip;
 993
 994        /* disable the ECC engine */
 995        WriteDOC (DOC_ECC_RESET, docptr, ECCConf);
 996        WriteDOC (DOC_ECC_DIS, docptr, ECCConf);
 997
 998        /* Reset the chip, see Software Requirement 11.4 item 1. */
 999        DoC_Command(this, NAND_CMD_RESET, CDSN_CTRL_WP);
1000
1001        /* issue the Read2 command to set the pointer to the Spare Data Area. */
1002        DoC_Command(this, NAND_CMD_READOOB, CDSN_CTRL_WP);
1003
1004        /* update address for 2M x 8bit devices. OOB starts on the second */
1005        /* page to maintain compatibility with doc_read_ecc. */
1006        if (this->page256) {
1007                if (!(ofs & 0x8))
1008                        ofs += 0x100;
1009                else
1010                        ofs -= 0x8;
1011        }
1012
1013        /* issue the Serial Data In command to initial the Page Program process */
1014        DoC_Command(this, NAND_CMD_SEQIN, 0);
1015        DoC_Address(this, ADDR_COLUMN_PAGE, ofs, 0, 0);
1016
1017        /* treat crossing 8-byte OOB data for 2M x 8bit devices */
1018        /* Note: datasheet says it should automaticaly wrap to the */
1019        /*       next OOB block, but it didn't work here. mf.      */
1020        if (this->page256 && ofs + len > (ofs | 0x7) + 1) {
1021                len256 = (ofs | 0x7) + 1 - ofs;
1022                DoC_WriteBuf(this, buf, len256);
1023
1024                DoC_Command(this, NAND_CMD_PAGEPROG, 0);
1025                DoC_Command(this, NAND_CMD_STATUS, 0);
1026                /* DoC_WaitReady() is implicit in DoC_Command */
1027
1028                dummy = ReadDOC(docptr, CDSNSlowIO);
1029                DoC_Delay(this, 2);
1030
1031                if (ReadDOC_(docptr, this->ioreg) & 1) {
1032                        printk(KERN_ERR "Error programming oob data\n");
1033                        /* There was an error */
1034                        *retlen = 0;
1035                        return -EIO;
1036                }
1037                DoC_Command(this, NAND_CMD_SEQIN, 0);
1038                DoC_Address(this, ADDR_COLUMN_PAGE, ofs & (~0x1ff), 0, 0);
1039        }
1040
1041        DoC_WriteBuf(this, &buf[len256], len - len256);
1042
1043        DoC_Command(this, NAND_CMD_PAGEPROG, 0);
1044        DoC_Command(this, NAND_CMD_STATUS, 0);
1045        /* DoC_WaitReady() is implicit in DoC_Command */
1046
1047        dummy = ReadDOC(docptr, CDSNSlowIO);
1048        DoC_Delay(this, 2);
1049
1050        if (ReadDOC_(docptr, this->ioreg) & 1) {
1051                printk(KERN_ERR "Error programming oob data\n");
1052                /* There was an error */
1053                *retlen = 0;
1054                return -EIO;
1055        }
1056
1057        *retlen = len;
1058        return 0;
1059
1060}
1061 
1062static int doc_write_oob(struct mtd_info *mtd, loff_t ofs, size_t len,
1063                         size_t * retlen, const u_char * buf)
1064{
1065        struct DiskOnChip *this = (struct DiskOnChip *) mtd->priv;
1066        int ret;
1067
1068        down(&this->lock);
1069        ret = doc_write_oob_nolock(mtd, ofs, len, retlen, buf);
1070
1071        up(&this->lock);
1072        return ret;
1073}
1074
1075static int doc_erase(struct mtd_info *mtd, struct erase_info *instr)
1076{
1077        struct DiskOnChip *this = (struct DiskOnChip *) mtd->priv;
1078        __u32 ofs = instr->addr;
1079        __u32 len = instr->len;
1080        volatile int dummy;
1081        unsigned long docptr;
1082        struct Nand *mychip;
1083
1084        down(&this->lock);
1085
1086        if (ofs & (mtd->erasesize-1) || len & (mtd->erasesize-1)) {
1087                up(&this->lock);
1088                return -EINVAL;
1089        }
1090
1091        instr->state = MTD_ERASING;
1092                
1093        docptr = this->virtadr;
1094
1095        /* FIXME: Do this in the background. Use timers or schedule_task() */
1096        while(len) {
1097                mychip = &this->chips[ofs >> this->chipshift];
1098
1099                if (this->curfloor != mychip->floor) {
1100                        DoC_SelectFloor(this, mychip->floor);
1101                        DoC_SelectChip(this, mychip->chip);
1102                } else if (this->curchip != mychip->chip) {
1103                        DoC_SelectChip(this, mychip->chip);
1104                }
1105                this->curfloor = mychip->floor;
1106                this->curchip = mychip->chip;
1107
1108                DoC_Command(this, NAND_CMD_ERASE1, 0);
1109                DoC_Address(this, ADDR_PAGE, ofs, 0, 0);
1110                DoC_Command(this, NAND_CMD_ERASE2, 0);
1111
1112                DoC_Command(this, NAND_CMD_STATUS, CDSN_CTRL_WP);
1113
1114                dummy = ReadDOC(docptr, CDSNSlowIO);
1115                DoC_Delay(this, 2);
1116                
1117                if (ReadDOC_(docptr, this->ioreg) & 1) {
1118                        printk(KERN_ERR "Error erasing at 0x%x\n", ofs);
1119                        /* There was an error */
1120                        instr->state = MTD_ERASE_FAILED;
1121                        goto callback;
1122                }
1123                ofs += mtd->erasesize;
1124                len -= mtd->erasesize;
1125        }
1126        instr->state = MTD_ERASE_DONE;
1127
1128 callback:
1129        if (instr->callback)
1130                instr->callback(instr);
1131
1132        up(&this->lock);
1133        return 0;
1134}
1135
1136
1137/****************************************************************************
1138 *
1139 * Module stuff
1140 *
1141 ****************************************************************************/
1142
1143int __init init_doc2000(void)
1144{
1145       inter_module_register(im_name, THIS_MODULE, &DoC2k_init);
1146       return 0;
1147}
1148
1149static void __exit cleanup_doc2000(void)
1150{
1151        struct mtd_info *mtd;
1152        struct DiskOnChip *this;
1153
1154        while ((mtd = doc2klist)) {
1155                this = (struct DiskOnChip *) mtd->priv;
1156                doc2klist = this->nextdoc;
1157
1158                del_mtd_device(mtd);
1159
1160                iounmap((void *) this->virtadr);
1161                kfree(this->chips);
1162                kfree(mtd);
1163        }
1164        inter_module_unregister(im_name);
1165}
1166
1167module_exit(cleanup_doc2000);
1168module_init(init_doc2000);
1169
1170MODULE_LICENSE("GPL");
1171MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org> et al.");
1172MODULE_DESCRIPTION("MTD driver for DiskOnChip 2000 and Millennium");
1173
1174