drivers/mtd/nand/raw/nand_onfi.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  Copyright (C) 2000 Steven J. Hill (sjhill@realitydiluted.com)
   4  *                2002-2006 Thomas Gleixner (tglx@linutronix.de)
   5  *
   6  *  Credits:
   7  *      David Woodhouse for adding multichip support
   8  *
   9  *      Aleph One Ltd. and Toby Churchill Ltd. for supporting the
  10  *      rework for 2K page size chips
  11  *
  12  * This file contains all ONFI helpers.
  13  */
  14
  15 #include <linux/slab.h>
  16
  17 #include "internals.h"
  18
  19 #define ONFI_PARAM_PAGES 3
  20
  21 u16 onfi_crc16(u16 crc, u8 const *p, size_t len)
  22 {
  23         int i;
  24         while (len--) {
  25                 crc ^= *p++ << 8;
  26                 for (i = 0; i < 8; i++)
  27                         crc = (crc << 1) ^ ((crc & 0x8000) ? 0x8005 : 0);
  28         }
  29
  30         return crc;
  31 }
  32
  33 /* Parse the Extended Parameter Page. */
  34 static int nand_flash_detect_ext_param_page(struct nand_chip *chip,
  35                                             struct nand_onfi_params *p)
  36 {
  37         struct nand_device *base = &chip->base;
  38         struct nand_ecc_props requirements;
  39         struct onfi_ext_param_page *ep;
  40         struct onfi_ext_section *s;
  41         struct onfi_ext_ecc_info *ecc;
  42         uint8_t *cursor;
  43         int ret;
  44         int len;
  45         int i;
  46
  47         len = le16_to_cpu(p->ext_param_page_length) * 16;
  48         ep = kmalloc(len, GFP_KERNEL);
  49         if (!ep)
  50                 return -ENOMEM;
  51
  52         /*
  53          * Use the Change Read Column command to skip the ONFI param pages and
  54          * ensure we read at the right location.
  55          */
  56         ret = nand_change_read_column_op(chip,
  57                                          sizeof(*p) * p->num_of_param_pages,
  58                                          ep, len, true);
  59         if (ret)
  60                 goto ext_out;
  61
  62         ret = -EINVAL;
  63         if ((onfi_crc16(ONFI_CRC_BASE, ((uint8_t *)ep) + 2, len - 2)
  64                 != le16_to_cpu(ep->crc))) {
  65                 pr_debug("fail in the CRC.\n");
  66                 goto ext_out;
  67         }
  68
  69         /*
  70          * Check the signature.
  71          * Do not strictly follow the ONFI spec, maybe changed in future.
  72          */
  73         if (strncmp(ep->sig, "EPPS", 4)) {
  74                 pr_debug("The signature is invalid.\n");
  75                 goto ext_out;
  76         }
  77
  78         /* find the ECC section. */
  79         cursor = (uint8_t *)(ep + 1);
  80         for (i = 0; i < ONFI_EXT_SECTION_MAX; i++) {
  81                 s = ep->sections + i;
  82                 if (s->type == ONFI_SECTION_TYPE_2)
  83                         break;
  84                 cursor += s->length * 16;
  85         }
  86         if (i == ONFI_EXT_SECTION_MAX) {
  87                 pr_debug("We can not find the ECC section.\n");
  88                 goto ext_out;
  89         }
  90
  91         /* get the info we want. */
  92         ecc = (struct onfi_ext_ecc_info *)cursor;
  93
  94         if (!ecc->codeword_size) {
  95                 pr_debug("Invalid codeword size\n");
  96                 goto ext_out;
  97         }
  98
  99         requirements.strength = ecc->ecc_bits;
 100         requirements.step_size = 1 << ecc->codeword_size;
 101         nanddev_set_ecc_requirements(base, &requirements);
 102
 103         ret = 0;
 104
 105 ext_out:
 106         kfree(ep);
 107         return ret;
 108 }
 109
 110 /*
 111  * Recover data with bit-wise majority
 112  */
 113 static void nand_bit_wise_majority(const void **srcbufs,
 114                                    unsigned int nsrcbufs,
 115                                    void *dstbuf,
 116                                    unsigned int bufsize)
 117 {
 118         int i, j, k;
 119
 120         for (i = 0; i < bufsize; i++) {
 121                 u8 val = 0;
 122
 123                 for (j = 0; j < 8; j++) {
 124                         unsigned int cnt = 0;
 125
 126                         for (k = 0; k < nsrcbufs; k++) {
 127                                 const u8 *srcbuf = srcbufs[k];
 128
 129                                 if (srcbuf[i] & BIT(j))
 130                                         cnt++;
 131                         }
 132
 133                         if (cnt > nsrcbufs / 2)
 134                                 val |= BIT(j);
 135                 }
 136
 137                 ((u8 *)dstbuf)[i] = val;
 138         }
 139 }
 140
 141 /*
 142  * Check if the NAND chip is ONFI compliant, returns 1 if it is, 0 otherwise.
 143  */
 144 int nand_onfi_detect(struct nand_chip *chip)
 145 {
 146         struct nand_device *base = &chip->base;
 147         struct mtd_info *mtd = nand_to_mtd(chip);
 148         struct nand_memory_organization *memorg;
 149         struct nand_onfi_params *p = NULL, *pbuf;
 150         struct onfi_params *onfi;
 151         bool use_datain = false;
 152         int onfi_version = 0;
 153         char id[4];
 154         int i, ret, val;
 155         u16 crc;
 156
 157         memorg = nanddev_get_memorg(&chip->base);
 158
 159         /* Try ONFI for unknown chip or LP */
 160         ret = nand_readid_op(chip, 0x20, id, sizeof(id));
 161         if (ret || strncmp(id, "ONFI", 4))
 162                 return 0;
 163
 164         /* ONFI chip: allocate a buffer to hold its parameter page */
 165         pbuf = kzalloc((sizeof(*pbuf) * ONFI_PARAM_PAGES), GFP_KERNEL);
 166         if (!pbuf)
 167                 return -ENOMEM;
 168
 169         if (!nand_has_exec_op(chip) ||
 170             !nand_read_data_op(chip, &pbuf[0], sizeof(*pbuf), true, true))
 171                 use_datain = true;
 172
 173         for (i = 0; i < ONFI_PARAM_PAGES; i++) {
 174                 if (!i)
 175                         ret = nand_read_param_page_op(chip, 0, &pbuf[i],
 176                                                       sizeof(*pbuf));
 177                 else if (use_datain)
 178                         ret = nand_read_data_op(chip, &pbuf[i], sizeof(*pbuf),
 179                                                 true, false);
 180                 else
 181                         ret = nand_change_read_column_op(chip, sizeof(*pbuf) * i,
 182                                                          &pbuf[i], sizeof(*pbuf),
 183                                                          true);
 184                 if (ret) {
 185                         ret = 0;
 186                         goto free_onfi_param_page;
 187                 }
 188
 189                 crc = onfi_crc16(ONFI_CRC_BASE, (u8 *)&pbuf[i], 254);
 190                 if (crc == le16_to_cpu(pbuf[i].crc)) {
 191                         p = &pbuf[i];
 192                         break;
 193                 }
 194         }
 195
 196         if (i == ONFI_PARAM_PAGES) {
 197                 const void *srcbufs[ONFI_PARAM_PAGES];
 198                 unsigned int j;
 199
 200                 for (j = 0; j < ONFI_PARAM_PAGES; j++)
 201                         srcbufs[j] = pbuf + j;
 202
 203                 pr_warn("Could not find a valid ONFI parameter page, trying bit-wise majority to recover it\n");
 204                 nand_bit_wise_majority(srcbufs, ONFI_PARAM_PAGES, pbuf,
 205                                        sizeof(*pbuf));
 206
 207                 crc = onfi_crc16(ONFI_CRC_BASE, (u8 *)pbuf, 254);
 208                 if (crc != le16_to_cpu(pbuf->crc)) {
 209                         pr_err("ONFI parameter recovery failed, aborting\n");
 210                         goto free_onfi_param_page;
 211                 }
 212                 p = pbuf;
 213         }
 214
 215         if (chip->manufacturer.desc && chip->manufacturer.desc->ops &&
 216             chip->manufacturer.desc->ops->fixup_onfi_param_page)
 217                 chip->manufacturer.desc->ops->fixup_onfi_param_page(chip, p);
 218
 219         /* Check version */
 220         val = le16_to_cpu(p->revision);
 221         if (val & ONFI_VERSION_2_3)
 222                 onfi_version = 23;
 223         else if (val & ONFI_VERSION_2_2)
 224                 onfi_version = 22;
 225         else if (val & ONFI_VERSION_2_1)
 226                 onfi_version = 21;
 227         else if (val & ONFI_VERSION_2_0)
 228                 onfi_version = 20;
 229         else if (val & ONFI_VERSION_1_0)
 230                 onfi_version = 10;
 231
 232         if (!onfi_version) {
 233                 pr_info("unsupported ONFI version: %d\n", val);
 234                 goto free_onfi_param_page;
 235         }
 236
 237         sanitize_string(p->manufacturer, sizeof(p->manufacturer));
 238         sanitize_string(p->model, sizeof(p->model));
 239         chip->parameters.model = kstrdup(p->model, GFP_KERNEL);
 240         if (!chip->parameters.model) {
 241                 ret = -ENOMEM;
 242                 goto free_onfi_param_page;
 243         }
 244
 245         memorg->pagesize = le32_to_cpu(p->byte_per_page);
 246         mtd->writesize = memorg->pagesize;
 247
 248         /*
 249          * pages_per_block and blocks_per_lun may not be a power-of-2 size
 250          * (don't ask me who thought of this...). MTD assumes that these
 251          * dimensions will be power-of-2, so just truncate the remaining area.
 252          */
 253         memorg->pages_per_eraseblock =
 254                         1 << (fls(le32_to_cpu(p->pages_per_block)) - 1);
 255         mtd->erasesize = memorg->pages_per_eraseblock * memorg->pagesize;
 256
 257         memorg->oobsize = le16_to_cpu(p->spare_bytes_per_page);
 258         mtd->oobsize = memorg->oobsize;
 259
 260         memorg->luns_per_target = p->lun_count;
 261         memorg->planes_per_lun = 1 << p->interleaved_bits;
 262
 263         /* See erasesize comment */
 264         memorg->eraseblocks_per_lun =
 265                 1 << (fls(le32_to_cpu(p->blocks_per_lun)) - 1);
 266         memorg->max_bad_eraseblocks_per_lun = le32_to_cpu(p->blocks_per_lun);
 267         memorg->bits_per_cell = p->bits_per_cell;
 268
 269         if (le16_to_cpu(p->features) & ONFI_FEATURE_16_BIT_BUS)
 270                 chip->options |= NAND_BUSWIDTH_16;
 271
 272         if (p->ecc_bits != 0xff) {
 273                 struct nand_ecc_props requirements = {
 274                         .strength = p->ecc_bits,
 275                         .step_size = 512,
 276                 };
 277
 278                 nanddev_set_ecc_requirements(base, &requirements);
 279         } else if (onfi_version >= 21 &&
 280                 (le16_to_cpu(p->features) & ONFI_FEATURE_EXT_PARAM_PAGE)) {
 281
 282                 /*
 283                  * The nand_flash_detect_ext_param_page() uses the
 284                  * Change Read Column command which maybe not supported
 285                  * by the chip->legacy.cmdfunc. So try to update the
 286                  * chip->legacy.cmdfunc now. We do not replace user supplied
 287                  * command function.
 288                  */
 289                 nand_legacy_adjust_cmdfunc(chip);
 290
 291                 /* The Extended Parameter Page is supported since ONFI 2.1. */
 292                 if (nand_flash_detect_ext_param_page(chip, p))
 293                         pr_warn("Failed to detect ONFI extended param page\n");
 294         } else {
 295                 pr_warn("Could not retrieve ONFI ECC requirements\n");
 296         }
 297
 298         /* Save some parameters from the parameter page for future use */
 299         if (le16_to_cpu(p->opt_cmd) & ONFI_OPT_CMD_SET_GET_FEATURES) {
 300                 chip->parameters.supports_set_get_features = true;
 301                 bitmap_set(chip->parameters.get_feature_list,
 302                            ONFI_FEATURE_ADDR_TIMING_MODE, 1);
 303                 bitmap_set(chip->parameters.set_feature_list,
 304                            ONFI_FEATURE_ADDR_TIMING_MODE, 1);
 305         }
 306
 307         onfi = kzalloc(sizeof(*onfi), GFP_KERNEL);
 308         if (!onfi) {
 309                 ret = -ENOMEM;
 310                 goto free_model;
 311         }
 312
 313         onfi->version = onfi_version;
 314         onfi->tPROG = le16_to_cpu(p->t_prog);
 315         onfi->tBERS = le16_to_cpu(p->t_bers);
 316         onfi->tR = le16_to_cpu(p->t_r);
 317         onfi->tCCS = le16_to_cpu(p->t_ccs);
 318         onfi->async_timing_mode = le16_to_cpu(p->async_timing_mode);
 319         onfi->vendor_revision = le16_to_cpu(p->vendor_revision);
 320         memcpy(onfi->vendor, p->vendor, sizeof(p->vendor));
 321         chip->parameters.onfi = onfi;
 322
 323         /* Identification done, free the full ONFI parameter page and exit */
 324         kfree(pbuf);
 325
 326         return 1;
 327
 328 free_model:
 329         kfree(chip->parameters.model);
 330 free_onfi_param_page:
 331         kfree(pbuf);
 332
 333         return ret;
 334 }