LXR uboot/drivers/mtd/nand/fsmc

   1/*
   2 * (C) Copyright 2010
   3 * Vipin Kumar, ST Microelectronics, vipin.kumar@st.com.
   4 *
   5 * (C) Copyright 2012
   6 * Amit Virdi, ST Microelectronics, amit.virdi@st.com.
   7 *
   8 * SPDX-License-Identifier:     GPL-2.0+
   9 */
  10
  11#include <common.h>
  12#include <nand.h>
  13#include <asm/io.h>
  14#include <linux/bitops.h>
  15#include <linux/err.h>
  16#include <linux/mtd/nand_ecc.h>
  17#include <linux/mtd/fsmc_nand.h>
  18#include <asm/arch/hardware.h>
  19
  20static u32 fsmc_version;
  21static struct fsmc_regs *const fsmc_regs_p = (struct fsmc_regs *)
  22        CONFIG_SYS_FSMC_BASE;
  23
  24/*
  25 * ECC4 and ECC1 have 13 bytes and 3 bytes of ecc respectively for 512 bytes of
  26 * data. ECC4 can correct up to 8 bits in 512 bytes of data while ECC1 can
  27 * correct 1 bit in 512 bytes
  28 */
  29
  30static struct nand_ecclayout fsmc_ecc4_lp_layout = {
  31        .eccbytes = 104,
  32        .eccpos = {  2,   3,   4,   5,   6,   7,   8,
  33                9,  10,  11,  12,  13,  14,
  34                18,  19,  20,  21,  22,  23,  24,
  35                25,  26,  27,  28,  29,  30,
  36                34,  35,  36,  37,  38,  39,  40,
  37                41,  42,  43,  44,  45,  46,
  38                50,  51,  52,  53,  54,  55,  56,
  39                57,  58,  59,  60,  61,  62,
  40                66,  67,  68,  69,  70,  71,  72,
  41                73,  74,  75,  76,  77,  78,
  42                82,  83,  84,  85,  86,  87,  88,
  43                89,  90,  91,  92,  93,  94,
  44                98,  99, 100, 101, 102, 103, 104,
  45                105, 106, 107, 108, 109, 110,
  46                114, 115, 116, 117, 118, 119, 120,
  47                121, 122, 123, 124, 125, 126
  48        },
  49        .oobfree = {
  50                {.offset = 15, .length = 3},
  51                {.offset = 31, .length = 3},
  52                {.offset = 47, .length = 3},
  53                {.offset = 63, .length = 3},
  54                {.offset = 79, .length = 3},
  55                {.offset = 95, .length = 3},
  56                {.offset = 111, .length = 3},
  57                {.offset = 127, .length = 1}
  58        }
  59};
  60
  61/*
  62 * ECC4 layout for NAND of pagesize 4096 bytes & OOBsize 224 bytes. 13*8 bytes
  63 * of OOB size is reserved for ECC, Byte no. 0 & 1 reserved for bad block & 118
  64 * bytes are free for use.
  65 */
  66static struct nand_ecclayout fsmc_ecc4_224_layout = {
  67        .eccbytes = 104,
  68        .eccpos = {  2,   3,   4,   5,   6,   7,   8,
  69                9,  10,  11,  12,  13,  14,
  70                18,  19,  20,  21,  22,  23,  24,
  71                25,  26,  27,  28,  29,  30,
  72                34,  35,  36,  37,  38,  39,  40,
  73                41,  42,  43,  44,  45,  46,
  74                50,  51,  52,  53,  54,  55,  56,
  75                57,  58,  59,  60,  61,  62,
  76                66,  67,  68,  69,  70,  71,  72,
  77                73,  74,  75,  76,  77,  78,
  78                82,  83,  84,  85,  86,  87,  88,
  79                89,  90,  91,  92,  93,  94,
  80                98,  99, 100, 101, 102, 103, 104,
  81                105, 106, 107, 108, 109, 110,
  82                114, 115, 116, 117, 118, 119, 120,
  83                121, 122, 123, 124, 125, 126
  84        },
  85        .oobfree = {
  86                {.offset = 15, .length = 3},
  87                {.offset = 31, .length = 3},
  88                {.offset = 47, .length = 3},
  89                {.offset = 63, .length = 3},
  90                {.offset = 79, .length = 3},
  91                {.offset = 95, .length = 3},
  92                {.offset = 111, .length = 3},
  93                {.offset = 127, .length = 97}
  94        }
  95};
  96
  97/*
  98 * ECC placement definitions in oobfree type format
  99 * There are 13 bytes of ecc for every 512 byte block and it has to be read
 100 * consecutively and immediately after the 512 byte data block for hardware to
 101 * generate the error bit offsets in 512 byte data
 102 * Managing the ecc bytes in the following way makes it easier for software to
 103 * read ecc bytes consecutive to data bytes. This way is similar to
 104 * oobfree structure maintained already in u-boot nand driver
 105 */
 106static struct fsmc_eccplace fsmc_eccpl_lp = {
 107        .eccplace = {
 108                {.offset = 2, .length = 13},
 109                {.offset = 18, .length = 13},
 110                {.offset = 34, .length = 13},
 111                {.offset = 50, .length = 13},
 112                {.offset = 66, .length = 13},
 113                {.offset = 82, .length = 13},
 114                {.offset = 98, .length = 13},
 115                {.offset = 114, .length = 13}
 116        }
 117};
 118
 119static struct nand_ecclayout fsmc_ecc4_sp_layout = {
 120        .eccbytes = 13,
 121        .eccpos = { 0,  1,  2,  3,  6,  7, 8,
 122                9, 10, 11, 12, 13, 14
 123        },
 124        .oobfree = {
 125                {.offset = 15, .length = 1},
 126        }
 127};
 128
 129static struct fsmc_eccplace fsmc_eccpl_sp = {
 130        .eccplace = {
 131                {.offset = 0, .length = 4},
 132                {.offset = 6, .length = 9}
 133        }
 134};
 135
 136static struct nand_ecclayout fsmc_ecc1_layout = {
 137        .eccbytes = 24,
 138        .eccpos = {2, 3, 4, 18, 19, 20, 34, 35, 36, 50, 51, 52,
 139                66, 67, 68, 82, 83, 84, 98, 99, 100, 114, 115, 116},
 140        .oobfree = {
 141                {.offset = 8, .length = 8},
 142                {.offset = 24, .length = 8},
 143                {.offset = 40, .length = 8},
 144                {.offset = 56, .length = 8},
 145                {.offset = 72, .length = 8},
 146                {.offset = 88, .length = 8},
 147                {.offset = 104, .length = 8},
 148                {.offset = 120, .length = 8}
 149        }
 150};
 151
 152/* Count the number of 0's in buff upto a max of max_bits */
 153static int count_written_bits(uint8_t *buff, int size, int max_bits)
 154{
 155        int k, written_bits = 0;
 156
 157        for (k = 0; k < size; k++) {
 158                written_bits += hweight8(~buff[k]);
 159                if (written_bits > max_bits)
 160                        break;
 161        }
 162
 163        return written_bits;
 164}
 165
 166static void fsmc_nand_hwcontrol(struct mtd_info *mtd, int cmd, uint ctrl)
 167{
 168        struct nand_chip *this = mtd_to_nand(mtd);
 169        ulong IO_ADDR_W;
 170
 171        if (ctrl & NAND_CTRL_CHANGE) {
 172                IO_ADDR_W = (ulong)this->IO_ADDR_W;
 173
 174                IO_ADDR_W &= ~(CONFIG_SYS_NAND_CLE | CONFIG_SYS_NAND_ALE);
 175                if (ctrl & NAND_CLE)
 176                        IO_ADDR_W |= CONFIG_SYS_NAND_CLE;
 177                if (ctrl & NAND_ALE)
 178                        IO_ADDR_W |= CONFIG_SYS_NAND_ALE;
 179
 180                if (ctrl & NAND_NCE) {
 181                        writel(readl(&fsmc_regs_p->pc) |
 182                                        FSMC_ENABLE, &fsmc_regs_p->pc);
 183                } else {
 184                        writel(readl(&fsmc_regs_p->pc) &
 185                                        ~FSMC_ENABLE, &fsmc_regs_p->pc);
 186                }
 187                this->IO_ADDR_W = (void *)IO_ADDR_W;
 188        }
 189
 190        if (cmd != NAND_CMD_NONE)
 191                writeb(cmd, this->IO_ADDR_W);
 192}
 193
 194static int fsmc_bch8_correct_data(struct mtd_info *mtd, u_char *dat,
 195                u_char *read_ecc, u_char *calc_ecc)
 196{
 197        /* The calculated ecc is actually the correction index in data */
 198        u32 err_idx[8];
 199        u32 num_err, i;
 200        u32 ecc1, ecc2, ecc3, ecc4;
 201
 202        num_err = (readl(&fsmc_regs_p->sts) >> 10) & 0xF;
 203
 204        if (likely(num_err == 0))
 205                return 0;
 206
 207        if (unlikely(num_err > 8)) {
 208                /*
 209                 * This is a temporary erase check. A newly erased page read
 210                 * would result in an ecc error because the oob data is also
 211                 * erased to FF and the calculated ecc for an FF data is not
 212                 * FF..FF.
 213                 * This is a workaround to skip performing correction in case
 214                 * data is FF..FF
 215                 *
 216                 * Logic:
 217                 * For every page, each bit written as 0 is counted until these
 218                 * number of bits are greater than 8 (the maximum correction
 219                 * capability of FSMC for each 512 + 13 bytes)
 220                 */
 221
 222                int bits_ecc = count_written_bits(read_ecc, 13, 8);
 223                int bits_data = count_written_bits(dat, 512, 8);
 224
 225                if ((bits_ecc + bits_data) <= 8) {
 226                        if (bits_data)
 227                                memset(dat, 0xff, 512);
 228                        return bits_data + bits_ecc;
 229                }
 230
 231                return -EBADMSG;
 232        }
 233
 234        ecc1 = readl(&fsmc_regs_p->ecc1);
 235        ecc2 = readl(&fsmc_regs_p->ecc2);
 236        ecc3 = readl(&fsmc_regs_p->ecc3);
 237        ecc4 = readl(&fsmc_regs_p->sts);
 238
 239        err_idx[0] = (ecc1 >> 0) & 0x1FFF;
 240        err_idx[1] = (ecc1 >> 13) & 0x1FFF;
 241        err_idx[2] = (((ecc2 >> 0) & 0x7F) << 6) | ((ecc1 >> 26) & 0x3F);
 242        err_idx[3] = (ecc2 >> 7) & 0x1FFF;
 243        err_idx[4] = (((ecc3 >> 0) & 0x1) << 12) | ((ecc2 >> 20) & 0xFFF);
 244        err_idx[5] = (ecc3 >> 1) & 0x1FFF;
 245        err_idx[6] = (ecc3 >> 14) & 0x1FFF;
 246        err_idx[7] = (((ecc4 >> 16) & 0xFF) << 5) | ((ecc3 >> 27) & 0x1F);
 247
 248        i = 0;
 249        while (i < num_err) {
 250                err_idx[i] ^= 3;
 251
 252                if (err_idx[i] < 512 * 8)
 253                        __change_bit(err_idx[i], dat);
 254
 255                i++;
 256        }
 257
 258        return num_err;
 259}
 260
 261static int fsmc_read_hwecc(struct mtd_info *mtd,
 262                        const u_char *data, u_char *ecc)
 263{
 264        u_int ecc_tmp;
 265        int timeout = CONFIG_SYS_HZ;
 266        ulong start;
 267
 268        switch (fsmc_version) {
 269        case FSMC_VER8:
 270                start = get_timer(0);
 271                while (get_timer(start) < timeout) {
 272                        /*
 273                         * Busy waiting for ecc computation
 274                         * to finish for 512 bytes
 275                         */
 276                        if (readl(&fsmc_regs_p->sts) & FSMC_CODE_RDY)
 277                                break;
 278                }
 279
 280                ecc_tmp = readl(&fsmc_regs_p->ecc1);
 281                ecc[0] = (u_char) (ecc_tmp >> 0);
 282                ecc[1] = (u_char) (ecc_tmp >> 8);
 283                ecc[2] = (u_char) (ecc_tmp >> 16);
 284                ecc[3] = (u_char) (ecc_tmp >> 24);
 285
 286                ecc_tmp = readl(&fsmc_regs_p->ecc2);
 287                ecc[4] = (u_char) (ecc_tmp >> 0);
 288                ecc[5] = (u_char) (ecc_tmp >> 8);
 289                ecc[6] = (u_char) (ecc_tmp >> 16);
 290                ecc[7] = (u_char) (ecc_tmp >> 24);
 291
 292                ecc_tmp = readl(&fsmc_regs_p->ecc3);
 293                ecc[8] = (u_char) (ecc_tmp >> 0);
 294                ecc[9] = (u_char) (ecc_tmp >> 8);
 295                ecc[10] = (u_char) (ecc_tmp >> 16);
 296                ecc[11] = (u_char) (ecc_tmp >> 24);
 297
 298                ecc_tmp = readl(&fsmc_regs_p->sts);
 299                ecc[12] = (u_char) (ecc_tmp >> 16);
 300                break;
 301
 302        default:
 303                ecc_tmp = readl(&fsmc_regs_p->ecc1);
 304                ecc[0] = (u_char) (ecc_tmp >> 0);
 305                ecc[1] = (u_char) (ecc_tmp >> 8);
 306                ecc[2] = (u_char) (ecc_tmp >> 16);
 307                break;
 308        }
 309
 310        return 0;
 311}
 312
 313void fsmc_enable_hwecc(struct mtd_info *mtd, int mode)
 314{
 315        writel(readl(&fsmc_regs_p->pc) & ~FSMC_ECCPLEN_256,
 316                        &fsmc_regs_p->pc);
 317        writel(readl(&fsmc_regs_p->pc) & ~FSMC_ECCEN,
 318                        &fsmc_regs_p->pc);
 319        writel(readl(&fsmc_regs_p->pc) | FSMC_ECCEN,
 320                        &fsmc_regs_p->pc);
 321}
 322
 323/*
 324 * fsmc_read_page_hwecc
 325 * @mtd:        mtd info structure
 326 * @chip:       nand chip info structure
 327 * @buf:        buffer to store read data
 328 * @oob_required:       caller expects OOB data read to chip->oob_poi
 329 * @page:       page number to read
 330 *
 331 * This routine is needed for fsmc verison 8 as reading from NAND chip has to be
 332 * performed in a strict sequence as follows:
 333 * data(512 byte) -> ecc(13 byte)
 334 * After this read, fsmc hardware generates and reports error data bits(upto a
 335 * max of 8 bits)
 336 */
 337static int fsmc_read_page_hwecc(struct mtd_info *mtd, struct nand_chip *chip,
 338                                 uint8_t *buf, int oob_required, int page)
 339{
 340        struct fsmc_eccplace *fsmc_eccpl;
 341        int i, j, s, stat, eccsize = chip->ecc.size;
 342        int eccbytes = chip->ecc.bytes;
 343        int eccsteps = chip->ecc.steps;
 344        uint8_t *p = buf;
 345        uint8_t *ecc_calc = chip->buffers->ecccalc;
 346        uint8_t *ecc_code = chip->buffers->ecccode;
 347        int off, len, group = 0;
 348        uint8_t oob[13] __attribute__ ((aligned (2)));
 349
 350        /* Differentiate between small and large page ecc place definitions */
 351        if (mtd->writesize == 512)
 352                fsmc_eccpl = &fsmc_eccpl_sp;
 353        else
 354                fsmc_eccpl = &fsmc_eccpl_lp;
 355
 356        for (i = 0, s = 0; s < eccsteps; s++, i += eccbytes, p += eccsize) {
 357
 358                chip->cmdfunc(mtd, NAND_CMD_READ0, s * eccsize, page);
 359                chip->ecc.hwctl(mtd, NAND_ECC_READ);
 360                chip->read_buf(mtd, p, eccsize);
 361
 362                for (j = 0; j < eccbytes;) {
 363                        off = fsmc_eccpl->eccplace[group].offset;
 364                        len = fsmc_eccpl->eccplace[group].length;
 365                        group++;
 366
 367                        /*
 368                         * length is intentionally kept a higher multiple of 2
 369                         * to read at least 13 bytes even in case of 16 bit NAND
 370                         * devices
 371                         */
 372                        if (chip->options & NAND_BUSWIDTH_16)
 373                                len = roundup(len, 2);
 374                        chip->cmdfunc(mtd, NAND_CMD_READOOB, off, page);
 375                        chip->read_buf(mtd, oob + j, len);
 376                        j += len;
 377                }
 378
 379                memcpy(&ecc_code[i], oob, 13);
 380                chip->ecc.calculate(mtd, p, &ecc_calc[i]);
 381
 382                stat = chip->ecc.correct(mtd, p, &ecc_code[i],
 383                                &ecc_calc[i]);
 384                if (stat < 0)
 385                        mtd->ecc_stats.failed++;
 386                else
 387                        mtd->ecc_stats.corrected += stat;
 388        }
 389
 390        return 0;
 391}
 392
 393#ifndef CONFIG_SPL_BUILD
 394/*
 395 * fsmc_nand_switch_ecc - switch the ECC operation between different engines
 396 *
 397 * @eccstrength         - the number of bits that could be corrected
 398 *                        (1 - HW, 4 - SW BCH4)
 399 */
 400int fsmc_nand_switch_ecc(uint32_t eccstrength)
 401{
 402        struct nand_chip *nand;
 403        struct mtd_info *mtd;
 404        int err;
 405
 406        /*
 407         * This functions is only called on SPEAr600 platforms, supporting
 408         * 1 bit HW ECC. The BCH8 HW ECC (FSMC_VER8) from the ST-Ericsson
 409         * Nomadik SoC is currently supporting this fsmc_nand_switch_ecc()
 410         * function, as it doesn't need to switch to a different ECC layout.
 411         */
 412        mtd = get_nand_dev_by_index(nand_curr_device);
 413        nand = mtd_to_nand(mtd);
 414
 415        /* Setup the ecc configurations again */
 416        if (eccstrength == 1) {
 417                nand->ecc.mode = NAND_ECC_HW;
 418                nand->ecc.bytes = 3;
 419                nand->ecc.strength = 1;
 420                nand->ecc.layout = &fsmc_ecc1_layout;
 421                nand->ecc.calculate = fsmc_read_hwecc;
 422                nand->ecc.correct = nand_correct_data;
 423        } else if (eccstrength == 4) {
 424                /*
 425                 * .calculate .correct and .bytes will be set in
 426                 * nand_scan_tail()
 427                 */
 428                nand->ecc.mode = NAND_ECC_SOFT_BCH;
 429                nand->ecc.strength = 4;
 430                nand->ecc.layout = NULL;
 431        } else {
 432                printf("Error: ECC strength %d not supported!\n", eccstrength);
 433        }
 434
 435        /* Update NAND handling after ECC mode switch */
 436        err = nand_scan_tail(mtd);
 437
 438        return err;
 439}
 440#endif /* CONFIG_SPL_BUILD */
 441
 442int fsmc_nand_init(struct nand_chip *nand)
 443{
 444        static int chip_nr;
 445        struct mtd_info *mtd;
 446        u32 peripid2 = readl(&fsmc_regs_p->peripid2);
 447
 448        fsmc_version = (peripid2 >> FSMC_REVISION_SHFT) &
 449                FSMC_REVISION_MSK;
 450
 451        writel(readl(&fsmc_regs_p->ctrl) | FSMC_WP, &fsmc_regs_p->ctrl);
 452
 453#if defined(CONFIG_SYS_FSMC_NAND_16BIT)
 454        writel(FSMC_DEVWID_16 | FSMC_DEVTYPE_NAND | FSMC_ENABLE | FSMC_WAITON,
 455                        &fsmc_regs_p->pc);
 456#elif defined(CONFIG_SYS_FSMC_NAND_8BIT)
 457        writel(FSMC_DEVWID_8 | FSMC_DEVTYPE_NAND | FSMC_ENABLE | FSMC_WAITON,
 458                        &fsmc_regs_p->pc);
 459#else
 460#error Please define CONFIG_SYS_FSMC_NAND_16BIT or CONFIG_SYS_FSMC_NAND_8BIT
 461#endif
 462        writel(readl(&fsmc_regs_p->pc) | FSMC_TCLR_1 | FSMC_TAR_1,
 463                        &fsmc_regs_p->pc);
 464        writel(FSMC_THIZ_1 | FSMC_THOLD_4 | FSMC_TWAIT_6 | FSMC_TSET_0,
 465                        &fsmc_regs_p->comm);
 466        writel(FSMC_THIZ_1 | FSMC_THOLD_4 | FSMC_TWAIT_6 | FSMC_TSET_0,
 467                        &fsmc_regs_p->attrib);
 468
 469        nand->options = 0;
 470#if defined(CONFIG_SYS_FSMC_NAND_16BIT)
 471        nand->options |= NAND_BUSWIDTH_16;
 472#endif
 473        nand->ecc.mode = NAND_ECC_HW;
 474        nand->ecc.size = 512;
 475        nand->ecc.calculate = fsmc_read_hwecc;
 476        nand->ecc.hwctl = fsmc_enable_hwecc;
 477        nand->cmd_ctrl = fsmc_nand_hwcontrol;
 478        nand->IO_ADDR_R = nand->IO_ADDR_W =
 479                (void  __iomem *)CONFIG_SYS_NAND_BASE;
 480        nand->badblockbits = 7;
 481
 482        mtd = nand_to_mtd(nand);
 483
 484        switch (fsmc_version) {
 485        case FSMC_VER8:
 486                nand->ecc.bytes = 13;
 487                nand->ecc.strength = 8;
 488                nand->ecc.correct = fsmc_bch8_correct_data;
 489                nand->ecc.read_page = fsmc_read_page_hwecc;
 490                if (mtd->writesize == 512)
 491                        nand->ecc.layout = &fsmc_ecc4_sp_layout;
 492                else {
 493                        if (mtd->oobsize == 224)
 494                                nand->ecc.layout = &fsmc_ecc4_224_layout;
 495                        else
 496                                nand->ecc.layout = &fsmc_ecc4_lp_layout;
 497                }
 498
 499                break;
 500        default:
 501                nand->ecc.bytes = 3;
 502                nand->ecc.strength = 1;
 503                nand->ecc.layout = &fsmc_ecc1_layout;
 504                nand->ecc.correct = nand_correct_data;
 505                break;
 506        }
 507
 508        /* Detect NAND chips */
 509        if (nand_scan_ident(mtd, CONFIG_SYS_MAX_NAND_DEVICE, NULL))
 510                return -ENXIO;
 511
 512        if (nand_scan_tail(mtd))
 513                return -ENXIO;
 514
 515        if (nand_register(chip_nr++, mtd))
 516                return -ENXIO;
 517
 518        return 0;
 519}
 520