drivers/mtd/nand/raw/fsl_elbc_nand.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /* Freescale Enhanced Local Bus Controller NAND driver
   3  *
   4  * Copyright © 2006-2007, 2010 Freescale Semiconductor
   5  *
   6  * Authors: Nick Spence <nick.spence@freescale.com>,
   7  *          Scott Wood <scottwood@freescale.com>
   8  *          Jack Lan <jack.lan@freescale.com>
   9  *          Roy Zang <tie-fei.zang@freescale.com>
  10  */
  11
  12 #include <linux/module.h>
  13 #include <linux/types.h>
  14 #include <linux/kernel.h>
  15 #include <linux/string.h>
  16 #include <linux/ioport.h>
  17 #include <linux/of_address.h>
  18 #include <linux/of_platform.h>
  19 #include <linux/platform_device.h>
  20 #include <linux/slab.h>
  21 #include <linux/interrupt.h>
  22
  23 #include <linux/mtd/mtd.h>
  24 #include <linux/mtd/rawnand.h>
  25 #include <linux/mtd/nand_ecc.h>
  26 #include <linux/mtd/partitions.h>
  27
  28 #include <asm/io.h>
  29 #include <asm/fsl_lbc.h>
  30
  31 #define MAX_BANKS 8
  32 #define ERR_BYTE 0xFF /* Value returned for read bytes when read failed */
  33 #define FCM_TIMEOUT_MSECS 500 /* Maximum number of mSecs to wait for FCM */
  34
  35 /* mtd information per set */
  36
  37 struct fsl_elbc_mtd {
  38         struct nand_chip chip;
  39         struct fsl_lbc_ctrl *ctrl;
  40
  41         struct device *dev;
  42         int bank;               /* Chip select bank number           */
  43         u8 __iomem *vbase;      /* Chip select base virtual address  */
  44         int page_size;          /* NAND page size (0=512, 1=2048)    */
  45         unsigned int fmr;       /* FCM Flash Mode Register value     */
  46 };
  47
  48 /* Freescale eLBC FCM controller information */
  49
  50 struct fsl_elbc_fcm_ctrl {
  51         struct nand_controller controller;
  52         struct fsl_elbc_mtd *chips[MAX_BANKS];
  53
  54         u8 __iomem *addr;        /* Address of assigned FCM buffer        */
  55         unsigned int page;       /* Last page written to / read from      */
  56         unsigned int read_bytes; /* Number of bytes read during command   */
  57         unsigned int column;     /* Saved column from SEQIN               */
  58         unsigned int index;      /* Pointer to next byte to 'read'        */
  59         unsigned int status;     /* status read from LTESR after last op  */
  60         unsigned int mdr;        /* UPM/FCM Data Register value           */
  61         unsigned int use_mdr;    /* Non zero if the MDR is to be set      */
  62         unsigned int oob;        /* Non zero if operating on OOB data     */
  63         unsigned int counter;    /* counter for the initializations       */
  64         unsigned int max_bitflips;  /* Saved during READ0 cmd             */
  65 };
  66
  67 /* These map to the positions used by the FCM hardware ECC generator */
  68
  69 static int fsl_elbc_ooblayout_ecc(struct mtd_info *mtd, int section,
  70                                   struct mtd_oob_region *oobregion)
  71 {
  72         struct nand_chip *chip = mtd_to_nand(mtd);
  73         struct fsl_elbc_mtd *priv = nand_get_controller_data(chip);
  74
  75         if (section >= chip->ecc.steps)
  76                 return -ERANGE;
  77
  78         oobregion->offset = (16 * section) + 6;
  79         if (priv->fmr & FMR_ECCM)
  80                 oobregion->offset += 2;
  81
  82         oobregion->length = chip->ecc.bytes;
  83
  84         return 0;
  85 }
  86
  87 static int fsl_elbc_ooblayout_free(struct mtd_info *mtd, int section,
  88                                    struct mtd_oob_region *oobregion)
  89 {
  90         struct nand_chip *chip = mtd_to_nand(mtd);
  91         struct fsl_elbc_mtd *priv = nand_get_controller_data(chip);
  92
  93         if (section > chip->ecc.steps)
  94                 return -ERANGE;
  95
  96         if (!section) {
  97                 oobregion->offset = 0;
  98                 if (mtd->writesize > 512)
  99                         oobregion->offset++;
 100                 oobregion->length = (priv->fmr & FMR_ECCM) ? 7 : 5;
 101         } else {
 102                 oobregion->offset = (16 * section) -
 103                                     ((priv->fmr & FMR_ECCM) ? 5 : 7);
 104                 if (section < chip->ecc.steps)
 105                         oobregion->length = 13;
 106                 else
 107                         oobregion->length = mtd->oobsize - oobregion->offset;
 108         }
 109
 110         return 0;
 111 }
 112
 113 static const struct mtd_ooblayout_ops fsl_elbc_ooblayout_ops = {
 114         .ecc = fsl_elbc_ooblayout_ecc,
 115         .free = fsl_elbc_ooblayout_free,
 116 };
 117
 118 /*
 119  * ELBC may use HW ECC, so that OOB offsets, that NAND core uses for bbt,
 120  * interfere with ECC positions, that's why we implement our own descriptors.
 121  * OOB {11, 5}, works for both SP and LP chips, with ECCM = 1 and ECCM = 0.
 122  */
 123 static u8 bbt_pattern[] = {'B', 'b', 't', '0' };
 124 static u8 mirror_pattern[] = {'1', 't', 'b', 'B' };
 125
 126 static struct nand_bbt_descr bbt_main_descr = {
 127         .options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE |
 128                    NAND_BBT_2BIT | NAND_BBT_VERSION,
 129         .offs = 11,
 130         .len = 4,
 131         .veroffs = 15,
 132         .maxblocks = 4,
 133         .pattern = bbt_pattern,
 134 };
 135
 136 static struct nand_bbt_descr bbt_mirror_descr = {
 137         .options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE |
 138                    NAND_BBT_2BIT | NAND_BBT_VERSION,
 139         .offs = 11,
 140         .len = 4,
 141         .veroffs = 15,
 142         .maxblocks = 4,
 143         .pattern = mirror_pattern,
 144 };
 145
 146 /*=================================*/
 147
 148 /*
 149  * Set up the FCM hardware block and page address fields, and the fcm
 150  * structure addr field to point to the correct FCM buffer in memory
 151  */
 152 static void set_addr(struct mtd_info *mtd, int column, int page_addr, int oob)
 153 {
 154         struct nand_chip *chip = mtd_to_nand(mtd);
 155         struct fsl_elbc_mtd *priv = nand_get_controller_data(chip);
 156         struct fsl_lbc_ctrl *ctrl = priv->ctrl;
 157         struct fsl_lbc_regs __iomem *lbc = ctrl->regs;
 158         struct fsl_elbc_fcm_ctrl *elbc_fcm_ctrl = ctrl->nand;
 159         int buf_num;
 160
 161         elbc_fcm_ctrl->page = page_addr;
 162
 163         if (priv->page_size) {
 164                 /*
 165                  * large page size chip : FPAR[PI] save the lowest 6 bits,
 166                  *                        FBAR[BLK] save the other bits.
 167                  */
 168                 out_be32(&lbc->fbar, page_addr >> 6);
 169                 out_be32(&lbc->fpar,
 170                          ((page_addr << FPAR_LP_PI_SHIFT) & FPAR_LP_PI) |
 171                          (oob ? FPAR_LP_MS : 0) | column);
 172                 buf_num = (page_addr & 1) << 2;
 173         } else {
 174                 /*
 175                  * small page size chip : FPAR[PI] save the lowest 5 bits,
 176                  *                        FBAR[BLK] save the other bits.
 177                  */
 178                 out_be32(&lbc->fbar, page_addr >> 5);
 179                 out_be32(&lbc->fpar,
 180                          ((page_addr << FPAR_SP_PI_SHIFT) & FPAR_SP_PI) |
 181                          (oob ? FPAR_SP_MS : 0) | column);
 182                 buf_num = page_addr & 7;
 183         }
 184
 185         elbc_fcm_ctrl->addr = priv->vbase + buf_num * 1024;
 186         elbc_fcm_ctrl->index = column;
 187
 188         /* for OOB data point to the second half of the buffer */
 189         if (oob)
 190                 elbc_fcm_ctrl->index += priv->page_size ? 2048 : 512;
 191
 192         dev_vdbg(priv->dev, "set_addr: bank=%d, "
 193                             "elbc_fcm_ctrl->addr=0x%p (0x%p), "
 194                             "index %x, pes %d ps %d\n",
 195                  buf_num, elbc_fcm_ctrl->addr, priv->vbase,
 196                  elbc_fcm_ctrl->index,
 197                  chip->phys_erase_shift, chip->page_shift);
 198 }
 199
 200 /*
 201  * execute FCM command and wait for it to complete
 202  */
 203 static int fsl_elbc_run_command(struct mtd_info *mtd)
 204 {
 205         struct nand_chip *chip = mtd_to_nand(mtd);
 206         struct fsl_elbc_mtd *priv = nand_get_controller_data(chip);
 207         struct fsl_lbc_ctrl *ctrl = priv->ctrl;
 208         struct fsl_elbc_fcm_ctrl *elbc_fcm_ctrl = ctrl->nand;
 209         struct fsl_lbc_regs __iomem *lbc = ctrl->regs;
 210
 211         /* Setup the FMR[OP] to execute without write protection */
 212         out_be32(&lbc->fmr, priv->fmr | 3);
 213         if (elbc_fcm_ctrl->use_mdr)
 214                 out_be32(&lbc->mdr, elbc_fcm_ctrl->mdr);
 215
 216         dev_vdbg(priv->dev,
 217                  "fsl_elbc_run_command: fmr=%08x fir=%08x fcr=%08x\n",
 218                  in_be32(&lbc->fmr), in_be32(&lbc->fir), in_be32(&lbc->fcr));
 219         dev_vdbg(priv->dev,
 220                  "fsl_elbc_run_command: fbar=%08x fpar=%08x "
 221                  "fbcr=%08x bank=%d\n",
 222                  in_be32(&lbc->fbar), in_be32(&lbc->fpar),
 223                  in_be32(&lbc->fbcr), priv->bank);
 224
 225         ctrl->irq_status = 0;
 226         /* execute special operation */
 227         out_be32(&lbc->lsor, priv->bank);
 228
 229         /* wait for FCM complete flag or timeout */
 230         wait_event_timeout(ctrl->irq_wait, ctrl->irq_status,
 231                            FCM_TIMEOUT_MSECS * HZ/1000);
 232         elbc_fcm_ctrl->status = ctrl->irq_status;
 233         /* store mdr value in case it was needed */
 234         if (elbc_fcm_ctrl->use_mdr)
 235                 elbc_fcm_ctrl->mdr = in_be32(&lbc->mdr);
 236
 237         elbc_fcm_ctrl->use_mdr = 0;
 238
 239         if (elbc_fcm_ctrl->status != LTESR_CC) {
 240                 dev_info(priv->dev,
 241                          "command failed: fir %x fcr %x status %x mdr %x\n",
 242                          in_be32(&lbc->fir), in_be32(&lbc->fcr),
 243                          elbc_fcm_ctrl->status, elbc_fcm_ctrl->mdr);
 244                 return -EIO;
 245         }
 246
 247         if (chip->ecc.mode != NAND_ECC_HW)
 248                 return 0;
 249
 250         elbc_fcm_ctrl->max_bitflips = 0;
 251
 252         if (elbc_fcm_ctrl->read_bytes == mtd->writesize + mtd->oobsize) {
 253                 uint32_t lteccr = in_be32(&lbc->lteccr);
 254                 /*
 255                  * if command was a full page read and the ELBC
 256                  * has the LTECCR register, then bits 12-15 (ppc order) of
 257                  * LTECCR indicates which 512 byte sub-pages had fixed errors.
 258                  * bits 28-31 are uncorrectable errors, marked elsewhere.
 259                  * for small page nand only 1 bit is used.
 260                  * if the ELBC doesn't have the lteccr register it reads 0
 261                  * FIXME: 4 bits can be corrected on NANDs with 2k pages, so
 262                  * count the number of sub-pages with bitflips and update
 263                  * ecc_stats.corrected accordingly.
 264                  */
 265                 if (lteccr & 0x000F000F)
 266                         out_be32(&lbc->lteccr, 0x000F000F); /* clear lteccr */
 267                 if (lteccr & 0x000F0000) {
 268                         mtd->ecc_stats.corrected++;
 269                         elbc_fcm_ctrl->max_bitflips = 1;
 270                 }
 271         }
 272
 273         return 0;
 274 }
 275
 276 static void fsl_elbc_do_read(struct nand_chip *chip, int oob)
 277 {
 278         struct fsl_elbc_mtd *priv = nand_get_controller_data(chip);
 279         struct fsl_lbc_ctrl *ctrl = priv->ctrl;
 280         struct fsl_lbc_regs __iomem *lbc = ctrl->regs;
 281
 282         if (priv->page_size) {
 283                 out_be32(&lbc->fir,
 284                          (FIR_OP_CM0 << FIR_OP0_SHIFT) |
 285                          (FIR_OP_CA  << FIR_OP1_SHIFT) |
 286                          (FIR_OP_PA  << FIR_OP2_SHIFT) |
 287                          (FIR_OP_CM1 << FIR_OP3_SHIFT) |
 288                          (FIR_OP_RBW << FIR_OP4_SHIFT));
 289
 290                 out_be32(&lbc->fcr, (NAND_CMD_READ0 << FCR_CMD0_SHIFT) |
 291                                     (NAND_CMD_READSTART << FCR_CMD1_SHIFT));
 292         } else {
 293                 out_be32(&lbc->fir,
 294                          (FIR_OP_CM0 << FIR_OP0_SHIFT) |
 295                          (FIR_OP_CA  << FIR_OP1_SHIFT) |
 296                          (FIR_OP_PA  << FIR_OP2_SHIFT) |
 297                          (FIR_OP_RBW << FIR_OP3_SHIFT));
 298
 299                 if (oob)
 300                         out_be32(&lbc->fcr, NAND_CMD_READOOB << FCR_CMD0_SHIFT);
 301                 else
 302                         out_be32(&lbc->fcr, NAND_CMD_READ0 << FCR_CMD0_SHIFT);
 303         }
 304 }
 305
 306 /* cmdfunc send commands to the FCM */
 307 static void fsl_elbc_cmdfunc(struct nand_chip *chip, unsigned int command,
 308                              int column, int page_addr)
 309 {
 310         struct mtd_info *mtd = nand_to_mtd(chip);
 311         struct fsl_elbc_mtd *priv = nand_get_controller_data(chip);
 312         struct fsl_lbc_ctrl *ctrl = priv->ctrl;
 313         struct fsl_elbc_fcm_ctrl *elbc_fcm_ctrl = ctrl->nand;
 314         struct fsl_lbc_regs __iomem *lbc = ctrl->regs;
 315
 316         elbc_fcm_ctrl->use_mdr = 0;
 317
 318         /* clear the read buffer */
 319         elbc_fcm_ctrl->read_bytes = 0;
 320         if (command != NAND_CMD_PAGEPROG)
 321                 elbc_fcm_ctrl->index = 0;
 322
 323         switch (command) {
 324         /* READ0 and READ1 read the entire buffer to use hardware ECC. */
 325         case NAND_CMD_READ1:
 326                 column += 256;
 327
 328         /* fall-through */
 329         case NAND_CMD_READ0:
 330                 dev_dbg(priv->dev,
 331                         "fsl_elbc_cmdfunc: NAND_CMD_READ0, page_addr:"
 332                         " 0x%x, column: 0x%x.\n", page_addr, column);
 333
 334
 335                 out_be32(&lbc->fbcr, 0); /* read entire page to enable ECC */
 336                 set_addr(mtd, 0, page_addr, 0);
 337
 338                 elbc_fcm_ctrl->read_bytes = mtd->writesize + mtd->oobsize;
 339                 elbc_fcm_ctrl->index += column;
 340
 341                 fsl_elbc_do_read(chip, 0);
 342                 fsl_elbc_run_command(mtd);
 343                 return;
 344
 345         /* RNDOUT moves the pointer inside the page */
 346         case NAND_CMD_RNDOUT:
 347                 dev_dbg(priv->dev,
 348                         "fsl_elbc_cmdfunc: NAND_CMD_RNDOUT, column: 0x%x.\n",
 349                         column);
 350
 351                 elbc_fcm_ctrl->index = column;
 352                 return;
 353
 354         /* READOOB reads only the OOB because no ECC is performed. */
 355         case NAND_CMD_READOOB:
 356                 dev_vdbg(priv->dev,
 357                          "fsl_elbc_cmdfunc: NAND_CMD_READOOB, page_addr:"
 358                          " 0x%x, column: 0x%x.\n", page_addr, column);
 359
 360                 out_be32(&lbc->fbcr, mtd->oobsize - column);
 361                 set_addr(mtd, column, page_addr, 1);
 362
 363                 elbc_fcm_ctrl->read_bytes = mtd->writesize + mtd->oobsize;
 364
 365                 fsl_elbc_do_read(chip, 1);
 366                 fsl_elbc_run_command(mtd);
 367                 return;
 368
 369         case NAND_CMD_READID:
 370         case NAND_CMD_PARAM:
 371                 dev_vdbg(priv->dev, "fsl_elbc_cmdfunc: NAND_CMD %x\n", command);
 372
 373                 out_be32(&lbc->fir, (FIR_OP_CM0 << FIR_OP0_SHIFT) |
 374                                     (FIR_OP_UA  << FIR_OP1_SHIFT) |
 375                                     (FIR_OP_RBW << FIR_OP2_SHIFT));
 376                 out_be32(&lbc->fcr, command << FCR_CMD0_SHIFT);
 377                 /*
 378                  * although currently it's 8 bytes for READID, we always read
 379                  * the maximum 256 bytes(for PARAM)
 380                  */
 381                 out_be32(&lbc->fbcr, 256);
 382                 elbc_fcm_ctrl->read_bytes = 256;
 383                 elbc_fcm_ctrl->use_mdr = 1;
 384                 elbc_fcm_ctrl->mdr = column;
 385                 set_addr(mtd, 0, 0, 0);
 386                 fsl_elbc_run_command(mtd);
 387                 return;
 388
 389         /* ERASE1 stores the block and page address */
 390         case NAND_CMD_ERASE1:
 391                 dev_vdbg(priv->dev,
 392                          "fsl_elbc_cmdfunc: NAND_CMD_ERASE1, "
 393                          "page_addr: 0x%x.\n", page_addr);
 394                 set_addr(mtd, 0, page_addr, 0);
 395                 return;
 396
 397         /* ERASE2 uses the block and page address from ERASE1 */
 398         case NAND_CMD_ERASE2:
 399                 dev_vdbg(priv->dev, "fsl_elbc_cmdfunc: NAND_CMD_ERASE2.\n");
 400
 401                 out_be32(&lbc->fir,
 402                          (FIR_OP_CM0 << FIR_OP0_SHIFT) |
 403                          (FIR_OP_PA  << FIR_OP1_SHIFT) |
 404                          (FIR_OP_CM2 << FIR_OP2_SHIFT) |
 405                          (FIR_OP_CW1 << FIR_OP3_SHIFT) |
 406                          (FIR_OP_RS  << FIR_OP4_SHIFT));
 407
 408                 out_be32(&lbc->fcr,
 409                          (NAND_CMD_ERASE1 << FCR_CMD0_SHIFT) |
 410                          (NAND_CMD_STATUS << FCR_CMD1_SHIFT) |
 411                          (NAND_CMD_ERASE2 << FCR_CMD2_SHIFT));
 412
 413                 out_be32(&lbc->fbcr, 0);
 414                 elbc_fcm_ctrl->read_bytes = 0;
 415                 elbc_fcm_ctrl->use_mdr = 1;
 416
 417                 fsl_elbc_run_command(mtd);
 418                 return;
 419
 420         /* SEQIN sets up the addr buffer and all registers except the length */
 421         case NAND_CMD_SEQIN: {
 422                 __be32 fcr;
 423                 dev_vdbg(priv->dev,
 424                          "fsl_elbc_cmdfunc: NAND_CMD_SEQIN/PAGE_PROG, "
 425                          "page_addr: 0x%x, column: 0x%x.\n",
 426                          page_addr, column);
 427
 428                 elbc_fcm_ctrl->column = column;
 429                 elbc_fcm_ctrl->use_mdr = 1;
 430
 431                 if (column >= mtd->writesize) {
 432                         /* OOB area */
 433                         column -= mtd->writesize;
 434                         elbc_fcm_ctrl->oob = 1;
 435                 } else {
 436                         WARN_ON(column != 0);
 437                         elbc_fcm_ctrl->oob = 0;
 438                 }
 439
 440                 fcr = (NAND_CMD_STATUS   << FCR_CMD1_SHIFT) |
 441                       (NAND_CMD_SEQIN    << FCR_CMD2_SHIFT) |
 442                       (NAND_CMD_PAGEPROG << FCR_CMD3_SHIFT);
 443
 444                 if (priv->page_size) {
 445                         out_be32(&lbc->fir,
 446                                  (FIR_OP_CM2 << FIR_OP0_SHIFT) |
 447                                  (FIR_OP_CA  << FIR_OP1_SHIFT) |
 448                                  (FIR_OP_PA  << FIR_OP2_SHIFT) |
 449                                  (FIR_OP_WB  << FIR_OP3_SHIFT) |
 450                                  (FIR_OP_CM3 << FIR_OP4_SHIFT) |
 451                                  (FIR_OP_CW1 << FIR_OP5_SHIFT) |
 452                                  (FIR_OP_RS  << FIR_OP6_SHIFT));
 453                 } else {
 454                         out_be32(&lbc->fir,
 455                                  (FIR_OP_CM0 << FIR_OP0_SHIFT) |
 456                                  (FIR_OP_CM2 << FIR_OP1_SHIFT) |
 457                                  (FIR_OP_CA  << FIR_OP2_SHIFT) |
 458                                  (FIR_OP_PA  << FIR_OP3_SHIFT) |
 459                                  (FIR_OP_WB  << FIR_OP4_SHIFT) |
 460                                  (FIR_OP_CM3 << FIR_OP5_SHIFT) |
 461                                  (FIR_OP_CW1 << FIR_OP6_SHIFT) |
 462                                  (FIR_OP_RS  << FIR_OP7_SHIFT));
 463
 464                         if (elbc_fcm_ctrl->oob)
 465                                 /* OOB area --> READOOB */
 466                                 fcr |= NAND_CMD_READOOB << FCR_CMD0_SHIFT;
 467                         else
 468                                 /* First 256 bytes --> READ0 */
 469                                 fcr |= NAND_CMD_READ0 << FCR_CMD0_SHIFT;
 470                 }
 471
 472                 out_be32(&lbc->fcr, fcr);
 473                 set_addr(mtd, column, page_addr, elbc_fcm_ctrl->oob);
 474                 return;
 475         }
 476
 477         /* PAGEPROG reuses all of the setup from SEQIN and adds the length */
 478         case NAND_CMD_PAGEPROG: {
 479                 dev_vdbg(priv->dev,
 480                          "fsl_elbc_cmdfunc: NAND_CMD_PAGEPROG "
 481                          "writing %d bytes.\n", elbc_fcm_ctrl->index);
 482
 483                 /* if the write did not start at 0 or is not a full page
 484                  * then set the exact length, otherwise use a full page
 485                  * write so the HW generates the ECC.
 486                  */
 487                 if (elbc_fcm_ctrl->oob || elbc_fcm_ctrl->column != 0 ||
 488                     elbc_fcm_ctrl->index != mtd->writesize + mtd->oobsize)
 489                         out_be32(&lbc->fbcr,
 490                                 elbc_fcm_ctrl->index - elbc_fcm_ctrl->column);
 491                 else
 492                         out_be32(&lbc->fbcr, 0);
 493
 494                 fsl_elbc_run_command(mtd);
 495                 return;
 496         }
 497
 498         /* CMD_STATUS must read the status byte while CEB is active */
 499         /* Note - it does not wait for the ready line */
 500         case NAND_CMD_STATUS:
 501                 out_be32(&lbc->fir,
 502                          (FIR_OP_CM0 << FIR_OP0_SHIFT) |
 503                          (FIR_OP_RBW << FIR_OP1_SHIFT));
 504                 out_be32(&lbc->fcr, NAND_CMD_STATUS << FCR_CMD0_SHIFT);
 505                 out_be32(&lbc->fbcr, 1);
 506                 set_addr(mtd, 0, 0, 0);
 507                 elbc_fcm_ctrl->read_bytes = 1;
 508
 509                 fsl_elbc_run_command(mtd);
 510
 511                 /* The chip always seems to report that it is
 512                  * write-protected, even when it is not.
 513                  */
 514                 setbits8(elbc_fcm_ctrl->addr, NAND_STATUS_WP);
 515                 return;
 516
 517         /* RESET without waiting for the ready line */
 518         case NAND_CMD_RESET:
 519                 dev_dbg(priv->dev, "fsl_elbc_cmdfunc: NAND_CMD_RESET.\n");
 520                 out_be32(&lbc->fir, FIR_OP_CM0 << FIR_OP0_SHIFT);
 521                 out_be32(&lbc->fcr, NAND_CMD_RESET << FCR_CMD0_SHIFT);
 522                 fsl_elbc_run_command(mtd);
 523                 return;
 524
 525         default:
 526                 dev_err(priv->dev,
 527                         "fsl_elbc_cmdfunc: error, unsupported command 0x%x.\n",
 528                         command);
 529         }
 530 }
 531
 532 static void fsl_elbc_select_chip(struct nand_chip *chip, int cs)
 533 {
 534         /* The hardware does not seem to support multiple
 535          * chips per bank.
 536          */
 537 }
 538
 539 /*
 540  * Write buf to the FCM Controller Data Buffer
 541  */
 542 static void fsl_elbc_write_buf(struct nand_chip *chip, const u8 *buf, int len)
 543 {
 544         struct mtd_info *mtd = nand_to_mtd(chip);
 545         struct fsl_elbc_mtd *priv = nand_get_controller_data(chip);
 546         struct fsl_elbc_fcm_ctrl *elbc_fcm_ctrl = priv->ctrl->nand;
 547         unsigned int bufsize = mtd->writesize + mtd->oobsize;
 548
 549         if (len <= 0) {
 550                 dev_err(priv->dev, "write_buf of %d bytes", len);
 551                 elbc_fcm_ctrl->status = 0;
 552                 return;
 553         }
 554
 555         if ((unsigned int)len > bufsize - elbc_fcm_ctrl->index) {
 556                 dev_err(priv->dev,
 557                         "write_buf beyond end of buffer "
 558                         "(%d requested, %u available)\n",
 559                         len, bufsize - elbc_fcm_ctrl->index);
 560                 len = bufsize - elbc_fcm_ctrl->index;
 561         }
 562
 563         memcpy_toio(&elbc_fcm_ctrl->addr[elbc_fcm_ctrl->index], buf, len);
 564         /*
 565          * This is workaround for the weird elbc hangs during nand write,
 566          * Scott Wood says: "...perhaps difference in how long it takes a
 567          * write to make it through the localbus compared to a write to IMMR
 568          * is causing problems, and sync isn't helping for some reason."
 569          * Reading back the last byte helps though.
 570          */
 571         in_8(&elbc_fcm_ctrl->addr[elbc_fcm_ctrl->index] + len - 1);
 572
 573         elbc_fcm_ctrl->index += len;
 574 }
 575
 576 /*
 577  * read a byte from either the FCM hardware buffer if it has any data left
 578  * otherwise issue a command to read a single byte.
 579  */
 580 static u8 fsl_elbc_read_byte(struct nand_chip *chip)
 581 {
 582         struct fsl_elbc_mtd *priv = nand_get_controller_data(chip);
 583         struct fsl_elbc_fcm_ctrl *elbc_fcm_ctrl = priv->ctrl->nand;
 584
 585         /* If there are still bytes in the FCM, then use the next byte. */
 586         if (elbc_fcm_ctrl->index < elbc_fcm_ctrl->read_bytes)
 587                 return in_8(&elbc_fcm_ctrl->addr[elbc_fcm_ctrl->index++]);
 588
 589         dev_err(priv->dev, "read_byte beyond end of buffer\n");
 590         return ERR_BYTE;
 591 }
 592
 593 /*
 594  * Read from the FCM Controller Data Buffer
 595  */
 596 static void fsl_elbc_read_buf(struct nand_chip *chip, u8 *buf, int len)
 597 {
 598         struct fsl_elbc_mtd *priv = nand_get_controller_data(chip);
 599         struct fsl_elbc_fcm_ctrl *elbc_fcm_ctrl = priv->ctrl->nand;
 600         int avail;
 601
 602         if (len < 0)
 603                 return;
 604
 605         avail = min((unsigned int)len,
 606                         elbc_fcm_ctrl->read_bytes - elbc_fcm_ctrl->index);
 607         memcpy_fromio(buf, &elbc_fcm_ctrl->addr[elbc_fcm_ctrl->index], avail);
 608         elbc_fcm_ctrl->index += avail;
 609
 610         if (len > avail)
 611                 dev_err(priv->dev,
 612                         "read_buf beyond end of buffer "
 613                         "(%d requested, %d available)\n",
 614                         len, avail);
 615 }
 616
 617 /* This function is called after Program and Erase Operations to
 618  * check for success or failure.
 619  */
 620 static int fsl_elbc_wait(struct nand_chip *chip)
 621 {
 622         struct fsl_elbc_mtd *priv = nand_get_controller_data(chip);
 623         struct fsl_elbc_fcm_ctrl *elbc_fcm_ctrl = priv->ctrl->nand;
 624
 625         if (elbc_fcm_ctrl->status != LTESR_CC)
 626                 return NAND_STATUS_FAIL;
 627
 628         /* The chip always seems to report that it is
 629          * write-protected, even when it is not.
 630          */
 631         return (elbc_fcm_ctrl->mdr & 0xff) | NAND_STATUS_WP;
 632 }
 633
 634 static int fsl_elbc_read_page(struct nand_chip *chip, uint8_t *buf,
 635                               int oob_required, int page)
 636 {
 637         struct mtd_info *mtd = nand_to_mtd(chip);
 638         struct fsl_elbc_mtd *priv = nand_get_controller_data(chip);
 639         struct fsl_lbc_ctrl *ctrl = priv->ctrl;
 640         struct fsl_elbc_fcm_ctrl *elbc_fcm_ctrl = ctrl->nand;
 641
 642         nand_read_page_op(chip, page, 0, buf, mtd->writesize);
 643         if (oob_required)
 644                 fsl_elbc_read_buf(chip, chip->oob_poi, mtd->oobsize);
 645
 646         if (fsl_elbc_wait(chip) & NAND_STATUS_FAIL)
 647                 mtd->ecc_stats.failed++;
 648
 649         return elbc_fcm_ctrl->max_bitflips;
 650 }
 651
 652 /* ECC will be calculated automatically, and errors will be detected in
 653  * waitfunc.
 654  */
 655 static int fsl_elbc_write_page(struct nand_chip *chip, const uint8_t *buf,
 656                                int oob_required, int page)
 657 {
 658         struct mtd_info *mtd = nand_to_mtd(chip);
 659
 660         nand_prog_page_begin_op(chip, page, 0, buf, mtd->writesize);
 661         fsl_elbc_write_buf(chip, chip->oob_poi, mtd->oobsize);
 662
 663         return nand_prog_page_end_op(chip);
 664 }
 665
 666 /* ECC will be calculated automatically, and errors will be detected in
 667  * waitfunc.
 668  */
 669 static int fsl_elbc_write_subpage(struct nand_chip *chip, uint32_t offset,
 670                                   uint32_t data_len, const uint8_t *buf,
 671                                   int oob_required, int page)
 672 {
 673         struct mtd_info *mtd = nand_to_mtd(chip);
 674
 675         nand_prog_page_begin_op(chip, page, 0, NULL, 0);
 676         fsl_elbc_write_buf(chip, buf, mtd->writesize);
 677         fsl_elbc_write_buf(chip, chip->oob_poi, mtd->oobsize);
 678         return nand_prog_page_end_op(chip);
 679 }
 680
 681 static int fsl_elbc_chip_init(struct fsl_elbc_mtd *priv)
 682 {
 683         struct fsl_lbc_ctrl *ctrl = priv->ctrl;
 684         struct fsl_lbc_regs __iomem *lbc = ctrl->regs;
 685         struct fsl_elbc_fcm_ctrl *elbc_fcm_ctrl = ctrl->nand;
 686         struct nand_chip *chip = &priv->chip;
 687         struct mtd_info *mtd = nand_to_mtd(chip);
 688
 689         dev_dbg(priv->dev, "eLBC Set Information for bank %d\n", priv->bank);
 690
 691         /* Fill in fsl_elbc_mtd structure */
 692         mtd->dev.parent = priv->dev;
 693         nand_set_flash_node(chip, priv->dev->of_node);
 694
 695         /* set timeout to maximum */
 696         priv->fmr = 15 << FMR_CWTO_SHIFT;
 697         if (in_be32(&lbc->bank[priv->bank].or) & OR_FCM_PGS)
 698                 priv->fmr |= FMR_ECCM;
 699
 700         /* fill in nand_chip structure */
 701         /* set up function call table */
 702         chip->legacy.read_byte = fsl_elbc_read_byte;
 703         chip->legacy.write_buf = fsl_elbc_write_buf;
 704         chip->legacy.read_buf = fsl_elbc_read_buf;
 705         chip->legacy.select_chip = fsl_elbc_select_chip;
 706         chip->legacy.cmdfunc = fsl_elbc_cmdfunc;
 707         chip->legacy.waitfunc = fsl_elbc_wait;
 708         chip->legacy.set_features = nand_get_set_features_notsupp;
 709         chip->legacy.get_features = nand_get_set_features_notsupp;
 710
 711         chip->bbt_td = &bbt_main_descr;
 712         chip->bbt_md = &bbt_mirror_descr;
 713
 714         /* set up nand options */
 715         chip->bbt_options = NAND_BBT_USE_FLASH;
 716
 717         chip->controller = &elbc_fcm_ctrl->controller;
 718         nand_set_controller_data(chip, priv);
 719
 720         return 0;
 721 }
 722
 723 static int fsl_elbc_attach_chip(struct nand_chip *chip)
 724 {
 725         struct mtd_info *mtd = nand_to_mtd(chip);
 726         struct fsl_elbc_mtd *priv = nand_get_controller_data(chip);
 727         struct fsl_lbc_ctrl *ctrl = priv->ctrl;
 728         struct fsl_lbc_regs __iomem *lbc = ctrl->regs;
 729         unsigned int al;
 730
 731         switch (chip->ecc.mode) {
 732         /*
 733          * if ECC was not chosen in DT, decide whether to use HW or SW ECC from
 734          * CS Base Register
 735          */
 736         case NAND_ECC_NONE:
 737                 /* If CS Base Register selects full hardware ECC then use it */
 738                 if ((in_be32(&lbc->bank[priv->bank].br) & BR_DECC) ==
 739                     BR_DECC_CHK_GEN) {
 740                         chip->ecc.read_page = fsl_elbc_read_page;
 741                         chip->ecc.write_page = fsl_elbc_write_page;
 742                         chip->ecc.write_subpage = fsl_elbc_write_subpage;
 743
 744                         chip->ecc.mode = NAND_ECC_HW;
 745                         mtd_set_ooblayout(mtd, &fsl_elbc_ooblayout_ops);
 746                         chip->ecc.size = 512;
 747                         chip->ecc.bytes = 3;
 748                         chip->ecc.strength = 1;
 749                 } else {
 750                         /* otherwise fall back to default software ECC */
 751                         chip->ecc.mode = NAND_ECC_SOFT;
 752                         chip->ecc.algo = NAND_ECC_HAMMING;
 753                 }
 754                 break;
 755
 756         /* if SW ECC was chosen in DT, we do not need to set anything here */
 757         case NAND_ECC_SOFT:
 758                 break;
 759
 760         /* should we also implement NAND_ECC_HW to do as the code above? */
 761         default:
 762                 return -EINVAL;
 763         }
 764
 765         /* calculate FMR Address Length field */
 766         al = 0;
 767         if (chip->pagemask & 0xffff0000)
 768                 al++;
 769         if (chip->pagemask & 0xff000000)
 770                 al++;
 771
 772         priv->fmr |= al << FMR_AL_SHIFT;
 773
 774         dev_dbg(priv->dev, "fsl_elbc_init: nand->numchips = %d\n",
 775                 nanddev_ntargets(&chip->base));
 776         dev_dbg(priv->dev, "fsl_elbc_init: nand->chipsize = %lld\n",
 777                 nanddev_target_size(&chip->base));
 778         dev_dbg(priv->dev, "fsl_elbc_init: nand->pagemask = %8x\n",
 779                 chip->pagemask);
 780         dev_dbg(priv->dev, "fsl_elbc_init: nand->legacy.chip_delay = %d\n",
 781                 chip->legacy.chip_delay);
 782         dev_dbg(priv->dev, "fsl_elbc_init: nand->badblockpos = %d\n",
 783                 chip->badblockpos);
 784         dev_dbg(priv->dev, "fsl_elbc_init: nand->chip_shift = %d\n",
 785                 chip->chip_shift);
 786         dev_dbg(priv->dev, "fsl_elbc_init: nand->page_shift = %d\n",
 787                 chip->page_shift);
 788         dev_dbg(priv->dev, "fsl_elbc_init: nand->phys_erase_shift = %d\n",
 789                 chip->phys_erase_shift);
 790         dev_dbg(priv->dev, "fsl_elbc_init: nand->ecc.mode = %d\n",
 791                 chip->ecc.mode);
 792         dev_dbg(priv->dev, "fsl_elbc_init: nand->ecc.steps = %d\n",
 793                 chip->ecc.steps);
 794         dev_dbg(priv->dev, "fsl_elbc_init: nand->ecc.bytes = %d\n",
 795                 chip->ecc.bytes);
 796         dev_dbg(priv->dev, "fsl_elbc_init: nand->ecc.total = %d\n",
 797                 chip->ecc.total);
 798         dev_dbg(priv->dev, "fsl_elbc_init: mtd->ooblayout = %p\n",
 799                 mtd->ooblayout);
 800         dev_dbg(priv->dev, "fsl_elbc_init: mtd->flags = %08x\n", mtd->flags);
 801         dev_dbg(priv->dev, "fsl_elbc_init: mtd->size = %lld\n", mtd->size);
 802         dev_dbg(priv->dev, "fsl_elbc_init: mtd->erasesize = %d\n",
 803                 mtd->erasesize);
 804         dev_dbg(priv->dev, "fsl_elbc_init: mtd->writesize = %d\n",
 805                 mtd->writesize);
 806         dev_dbg(priv->dev, "fsl_elbc_init: mtd->oobsize = %d\n",
 807                 mtd->oobsize);
 808
 809         /* adjust Option Register and ECC to match Flash page size */
 810         if (mtd->writesize == 512) {
 811                 priv->page_size = 0;
 812                 clrbits32(&lbc->bank[priv->bank].or, OR_FCM_PGS);
 813         } else if (mtd->writesize == 2048) {
 814                 priv->page_size = 1;
 815                 setbits32(&lbc->bank[priv->bank].or, OR_FCM_PGS);
 816         } else {
 817                 dev_err(priv->dev,
 818                         "fsl_elbc_init: page size %d is not supported\n",
 819                         mtd->writesize);
 820                 return -ENOTSUPP;
 821         }
 822
 823         return 0;
 824 }
 825
 826 static const struct nand_controller_ops fsl_elbc_controller_ops = {
 827         .attach_chip = fsl_elbc_attach_chip,
 828 };
 829
 830 static int fsl_elbc_chip_remove(struct fsl_elbc_mtd *priv)
 831 {
 832         struct fsl_elbc_fcm_ctrl *elbc_fcm_ctrl = priv->ctrl->nand;
 833         struct mtd_info *mtd = nand_to_mtd(&priv->chip);
 834
 835         kfree(mtd->name);
 836
 837         if (priv->vbase)
 838                 iounmap(priv->vbase);
 839
 840         elbc_fcm_ctrl->chips[priv->bank] = NULL;
 841         kfree(priv);
 842         return 0;
 843 }
 844
 845 static DEFINE_MUTEX(fsl_elbc_nand_mutex);
 846
 847 static int fsl_elbc_nand_probe(struct platform_device *pdev)
 848 {
 849         struct fsl_lbc_regs __iomem *lbc;
 850         struct fsl_elbc_mtd *priv;
 851         struct resource res;
 852         struct fsl_elbc_fcm_ctrl *elbc_fcm_ctrl;
 853         static const char *part_probe_types[]
 854                 = { "cmdlinepart", "RedBoot", "ofpart", NULL };
 855         int ret;
 856         int bank;
 857         struct device *dev;
 858         struct device_node *node = pdev->dev.of_node;
 859         struct mtd_info *mtd;
 860
 861         if (!fsl_lbc_ctrl_dev || !fsl_lbc_ctrl_dev->regs)
 862                 return -ENODEV;
 863         lbc = fsl_lbc_ctrl_dev->regs;
 864         dev = fsl_lbc_ctrl_dev->dev;
 865
 866         /* get, allocate and map the memory resource */
 867         ret = of_address_to_resource(node, 0, &res);
 868         if (ret) {
 869                 dev_err(dev, "failed to get resource\n");
 870                 return ret;
 871         }
 872
 873         /* find which chip select it is connected to */
 874         for (bank = 0; bank < MAX_BANKS; bank++)
 875                 if ((in_be32(&lbc->bank[bank].br) & BR_V) &&
 876                     (in_be32(&lbc->bank[bank].br) & BR_MSEL) == BR_MS_FCM &&
 877                     (in_be32(&lbc->bank[bank].br) &
 878                      in_be32(&lbc->bank[bank].or) & BR_BA)
 879                      == fsl_lbc_addr(res.start))
 880                         break;
 881
 882         if (bank >= MAX_BANKS) {
 883                 dev_err(dev, "address did not match any chip selects\n");
 884                 return -ENODEV;
 885         }
 886
 887         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
 888         if (!priv)
 889                 return -ENOMEM;
 890
 891         mutex_lock(&fsl_elbc_nand_mutex);
 892         if (!fsl_lbc_ctrl_dev->nand) {
 893                 elbc_fcm_ctrl = kzalloc(sizeof(*elbc_fcm_ctrl), GFP_KERNEL);
 894                 if (!elbc_fcm_ctrl) {
 895                         mutex_unlock(&fsl_elbc_nand_mutex);
 896                         ret = -ENOMEM;
 897                         goto err;
 898                 }
 899                 elbc_fcm_ctrl->counter++;
 900
 901                 nand_controller_init(&elbc_fcm_ctrl->controller);
 902                 fsl_lbc_ctrl_dev->nand = elbc_fcm_ctrl;
 903         } else {
 904                 elbc_fcm_ctrl = fsl_lbc_ctrl_dev->nand;
 905         }
 906         mutex_unlock(&fsl_elbc_nand_mutex);
 907
 908         elbc_fcm_ctrl->chips[bank] = priv;
 909         priv->bank = bank;
 910         priv->ctrl = fsl_lbc_ctrl_dev;
 911         priv->dev = &pdev->dev;
 912         dev_set_drvdata(priv->dev, priv);
 913
 914         priv->vbase = ioremap(res.start, resource_size(&res));
 915         if (!priv->vbase) {
 916                 dev_err(dev, "failed to map chip region\n");
 917                 ret = -ENOMEM;
 918                 goto err;
 919         }
 920
 921         mtd = nand_to_mtd(&priv->chip);
 922         mtd->name = kasprintf(GFP_KERNEL, "%llx.flash", (u64)res.start);
 923         if (!nand_to_mtd(&priv->chip)->name) {
 924                 ret = -ENOMEM;
 925                 goto err;
 926         }
 927
 928         ret = fsl_elbc_chip_init(priv);
 929         if (ret)
 930                 goto err;
 931
 932         priv->chip.controller->ops = &fsl_elbc_controller_ops;
 933         ret = nand_scan(&priv->chip, 1);
 934         if (ret)
 935                 goto err;
 936
 937         /* First look for RedBoot table or partitions on the command
 938          * line, these take precedence over device tree information */
 939         ret = mtd_device_parse_register(mtd, part_probe_types, NULL, NULL, 0);
 940         if (ret)
 941                 goto cleanup_nand;
 942
 943         pr_info("eLBC NAND device at 0x%llx, bank %d\n",
 944                 (unsigned long long)res.start, priv->bank);
 945
 946         return 0;
 947
 948 cleanup_nand:
 949         nand_cleanup(&priv->chip);
 950 err:
 951         fsl_elbc_chip_remove(priv);
 952
 953         return ret;
 954 }
 955
 956 static int fsl_elbc_nand_remove(struct platform_device *pdev)
 957 {
 958         struct fsl_elbc_fcm_ctrl *elbc_fcm_ctrl = fsl_lbc_ctrl_dev->nand;
 959         struct fsl_elbc_mtd *priv = dev_get_drvdata(&pdev->dev);
 960
 961         nand_release(&priv->chip);
 962         fsl_elbc_chip_remove(priv);
 963
 964         mutex_lock(&fsl_elbc_nand_mutex);
 965         elbc_fcm_ctrl->counter--;
 966         if (!elbc_fcm_ctrl->counter) {
 967                 fsl_lbc_ctrl_dev->nand = NULL;
 968                 kfree(elbc_fcm_ctrl);
 969         }
 970         mutex_unlock(&fsl_elbc_nand_mutex);
 971
 972         return 0;
 973
 974 }
 975
 976 static const struct of_device_id fsl_elbc_nand_match[] = {
 977         { .compatible = "fsl,elbc-fcm-nand", },
 978         {}
 979 };
 980 MODULE_DEVICE_TABLE(of, fsl_elbc_nand_match);
 981
 982 static struct platform_driver fsl_elbc_nand_driver = {
 983         .driver = {
 984                 .name = "fsl,elbc-fcm-nand",
 985                 .of_match_table = fsl_elbc_nand_match,
 986         },
 987         .probe = fsl_elbc_nand_probe,
 988         .remove = fsl_elbc_nand_remove,
 989 };
 990
 991 module_platform_driver(fsl_elbc_nand_driver);
 992
 993 MODULE_LICENSE("GPL");
 994 MODULE_AUTHOR("Freescale");
 995 MODULE_DESCRIPTION("Freescale Enhanced Local Bus Controller MTD NAND driver");