drivers/mtd/nand/raw/nand_onfi.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  Copyright (C) 2000 Steven J. Hill ([email protected])
   4  *                2002-2006 Thomas Gleixner ([email protected])
   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 u16 onfi_crc16(u16 crc, u8 const *p, size_t len)
  20 {
  21         int i;
  22         while (len--) {
  23                 crc ^= *p++ << 8;
  24                 for (i = 0; i < 8; i++)
  25                         crc = (crc << 1) ^ ((crc & 0x8000) ? 0x8005 : 0);
  26         }
  27
  28         return crc;
  29 }
  30
  31 /* Parse the Extended Parameter Page. */
  32 static int nand_flash_detect_ext_param_page(struct nand_chip *chip,
  33                                             struct nand_onfi_params *p)
  34 {
  35         struct onfi_ext_param_page *ep;
  36         struct onfi_ext_section *s;
  37         struct onfi_ext_ecc_info *ecc;
  38         uint8_t *cursor;
  39         int ret;
  40         int len;
  41         int i;
  42
  43         len = le16_to_cpu(p->ext_param_page_length) * 16;
  44         ep = kmalloc(len, GFP_KERNEL);
  45         if (!ep)
  46                 return -ENOMEM;
  47
  48         /* Send our own NAND_CMD_PARAM. */
  49         ret = nand_read_param_page_op(chip, 0, NULL, 0);
  50         if (ret)
  51                 goto ext_out;
  52
  53         /* Use the Change Read Column command to skip the ONFI param pages. */
  54         ret = nand_change_read_column_op(chip,
  55                                          sizeof(*p) * p->num_of_param_pages,
  56                                          ep, len, true);
  57         if (ret)
  58                 goto ext_out;
  59
  60         ret = -EINVAL;
  61         if ((onfi_crc16(ONFI_CRC_BASE, ((uint8_t *)ep) + 2, len - 2)
  62                 != le16_to_cpu(ep->crc))) {
  63                 pr_debug("fail in the CRC.\n");
  64                 goto ext_out;
  65         }
  66
  67         /*
  68          * Check the signature.
  69          * Do not strictly follow the ONFI spec, maybe changed in future.
  70          */
  71         if (strncmp(ep->sig, "EPPS", 4)) {
  72                 pr_debug("The signature is invalid.\n");
  73                 goto ext_out;
  74         }
  75
  76         /* find the ECC section. */
  77         cursor = (uint8_t *)(ep + 1);
  78         for (i = 0; i < ONFI_EXT_SECTION_MAX; i++) {
  79                 s = ep->sections + i;
  80                 if (s->type == ONFI_SECTION_TYPE_2)
  81                         break;
  82                 cursor += s->length * 16;
  83         }
  84         if (i == ONFI_EXT_SECTION_MAX) {
  85                 pr_debug("We can not find the ECC section.\n");
  86                 goto ext_out;
  87         }
  88
  89         /* get the info we want. */
  90         ecc = (struct onfi_ext_ecc_info *)cursor;
  91
  92         if (!ecc->codeword_size) {
  93                 pr_debug("Invalid codeword size\n");
  94                 goto ext_out;
  95         }
  96
  97         chip->ecc_strength_ds = ecc->ecc_bits;
  98         chip->ecc_step_ds = 1 << ecc->codeword_size;
  99         ret = 0;
 100
 101 ext_out:
 102         kfree(ep);
 103         return ret;
 104 }
 105
 106 /*
 107  * Recover data with bit-wise majority
 108  */
 109 static void nand_bit_wise_majority(const void **srcbufs,
 110                                    unsigned int nsrcbufs,
 111                                    void *dstbuf,
 112                                    unsigned int bufsize)
 113 {
 114         int i, j, k;
 115
 116         for (i = 0; i < bufsize; i++) {
 117                 u8 val = 0;
 118
 119                 for (j = 0; j < 8; j++) {
 120                         unsigned int cnt = 0;
 121
 122                         for (k = 0; k < nsrcbufs; k++) {
 123                                 const u8 *srcbuf = srcbufs[k];
 124
 125                                 if (srcbuf[i] & BIT(j))
 126                                         cnt++;
 127                         }
 128
 129                         if (cnt > nsrcbufs / 2)
 130                                 val |= BIT(j);
 131                 }
 132
 133                 ((u8 *)dstbuf)[i] = val;
 134         }
 135 }
 136
 137 /*
 138  * Check if the NAND chip is ONFI compliant, returns 1 if it is, 0 otherwise.
 139  */
 140 int nand_onfi_detect(struct nand_chip *chip)
 141 {
 142         struct mtd_info *mtd = nand_to_mtd(chip);
 143         struct nand_onfi_params *p;
 144         struct onfi_params *onfi;
 145         int onfi_version = 0;
 146         char id[4];
 147         int i, ret, val;
 148
 149         /* Try ONFI for unknown chip or LP */
 150         ret = nand_readid_op(chip, 0x20, id, sizeof(id));
 151         if (ret || strncmp(id, "ONFI", 4))
 152                 return 0;
 153
 154         /* ONFI chip: allocate a buffer to hold its parameter page */
 155         p = kzalloc((sizeof(*p) * 3), GFP_KERNEL);
 156         if (!p)
 157                 return -ENOMEM;
 158
 159         ret = nand_read_param_page_op(chip, 0, NULL, 0);
 160         if (ret) {
 161                 ret = 0;
 162                 goto free_onfi_param_page;
 163         }
 164
 165         for (i = 0; i < 3; i++) {
 166                 ret = nand_read_data_op(chip, &p[i], sizeof(*p), true);
 167                 if (ret) {
 168                         ret = 0;
 169                         goto free_onfi_param_page;
 170                 }
 171
 172                 if (onfi_crc16(ONFI_CRC_BASE, (u8 *)&p[i], 254) ==
 173                                 le16_to_cpu(p->crc)) {
 174                         if (i)
 175                                 memcpy(p, &p[i], sizeof(*p));
 176                         break;
 177                 }
 178         }
 179
 180         if (i == 3) {
 181                 const void *srcbufs[3] = {p, p + 1, p + 2};
 182
 183                 pr_warn("Could not find a valid ONFI parameter page, trying bit-wise majority to recover it\n");
 184                 nand_bit_wise_majority(srcbufs, ARRAY_SIZE(srcbufs), p,
 185                                        sizeof(*p));
 186
 187                 if (onfi_crc16(ONFI_CRC_BASE, (u8 *)p, 254) !=
 188                                 le16_to_cpu(p->crc)) {
 189                         pr_err("ONFI parameter recovery failed, aborting\n");
 190                         goto free_onfi_param_page;
 191                 }
 192         }
 193
 194         if (chip->manufacturer.desc && chip->manufacturer.desc->ops &&
 195             chip->manufacturer.desc->ops->fixup_onfi_param_page)
 196                 chip->manufacturer.desc->ops->fixup_onfi_param_page(chip, p);
 197
 198         /* Check version */
 199         val = le16_to_cpu(p->revision);
 200         if (val & ONFI_VERSION_2_3)
 201                 onfi_version = 23;
 202         else if (val & ONFI_VERSION_2_2)
 203                 onfi_version = 22;
 204         else if (val & ONFI_VERSION_2_1)
 205                 onfi_version = 21;
 206         else if (val & ONFI_VERSION_2_0)
 207                 onfi_version = 20;
 208         else if (val & ONFI_VERSION_1_0)
 209                 onfi_version = 10;
 210
 211         if (!onfi_version) {
 212                 pr_info("unsupported ONFI version: %d\n", val);
 213                 goto free_onfi_param_page;
 214         }
 215
 216         sanitize_string(p->manufacturer, sizeof(p->manufacturer));
 217         sanitize_string(p->model, sizeof(p->model));
 218         chip->parameters.model = kstrdup(p->model, GFP_KERNEL);
 219         if (!chip->parameters.model) {
 220                 ret = -ENOMEM;
 221                 goto free_onfi_param_page;
 222         }
 223
 224         mtd->writesize = le32_to_cpu(p->byte_per_page);
 225
 226         /*
 227          * pages_per_block and blocks_per_lun may not be a power-of-2 size
 228          * (don't ask me who thought of this...). MTD assumes that these
 229          * dimensions will be power-of-2, so just truncate the remaining area.
 230          */
 231         mtd->erasesize = 1 << (fls(le32_to_cpu(p->pages_per_block)) - 1);
 232         mtd->erasesize *= mtd->writesize;
 233
 234         mtd->oobsize = le16_to_cpu(p->spare_bytes_per_page);
 235
 236         /* See erasesize comment */
 237         chip->chipsize = 1 << (fls(le32_to_cpu(p->blocks_per_lun)) - 1);
 238         chip->chipsize *= (uint64_t)mtd->erasesize * p->lun_count;
 239         chip->bits_per_cell = p->bits_per_cell;
 240
 241         chip->max_bb_per_die = le16_to_cpu(p->bb_per_lun);
 242         chip->blocks_per_die = le32_to_cpu(p->blocks_per_lun);
 243
 244         if (le16_to_cpu(p->features) & ONFI_FEATURE_16_BIT_BUS)
 245                 chip->options |= NAND_BUSWIDTH_16;
 246
 247         if (p->ecc_bits != 0xff) {
 248                 chip->ecc_strength_ds = p->ecc_bits;
 249                 chip->ecc_step_ds = 512;
 250         } else if (onfi_version >= 21 &&
 251                 (le16_to_cpu(p->features) & ONFI_FEATURE_EXT_PARAM_PAGE)) {
 252
 253                 /*
 254                  * The nand_flash_detect_ext_param_page() uses the
 255                  * Change Read Column command which maybe not supported
 256                  * by the chip->legacy.cmdfunc. So try to update the
 257                  * chip->legacy.cmdfunc now. We do not replace user supplied
 258                  * command function.
 259                  */
 260                 nand_legacy_adjust_cmdfunc(chip);
 261
 262                 /* The Extended Parameter Page is supported since ONFI 2.1. */
 263                 if (nand_flash_detect_ext_param_page(chip, p))
 264                         pr_warn("Failed to detect ONFI extended param page\n");
 265         } else {
 266                 pr_warn("Could not retrieve ONFI ECC requirements\n");
 267         }
 268
 269         /* Save some parameters from the parameter page for future use */
 270         if (le16_to_cpu(p->opt_cmd) & ONFI_OPT_CMD_SET_GET_FEATURES) {
 271                 chip->parameters.supports_set_get_features = true;
 272                 bitmap_set(chip->parameters.get_feature_list,
 273                            ONFI_FEATURE_ADDR_TIMING_MODE, 1);
 274                 bitmap_set(chip->parameters.set_feature_list,
 275                            ONFI_FEATURE_ADDR_TIMING_MODE, 1);
 276         }
 277
 278         onfi = kzalloc(sizeof(*onfi), GFP_KERNEL);
 279         if (!onfi) {
 280                 ret = -ENOMEM;
 281                 goto free_model;
 282         }
 283
 284         onfi->version = onfi_version;
 285         onfi->tPROG = le16_to_cpu(p->t_prog);
 286         onfi->tBERS = le16_to_cpu(p->t_bers);
 287         onfi->tR = le16_to_cpu(p->t_r);
 288         onfi->tCCS = le16_to_cpu(p->t_ccs);
 289         onfi->async_timing_mode = le16_to_cpu(p->async_timing_mode);
 290         onfi->vendor_revision = le16_to_cpu(p->vendor_revision);
 291         memcpy(onfi->vendor, p->vendor, sizeof(p->vendor));
 292         chip->parameters.onfi = onfi;
 293
 294         /* Identification done, free the full ONFI parameter page and exit */
 295         kfree(p);
 296
 297         return 1;
 298
 299 free_model:
 300         kfree(chip->parameters.model);
 301 free_onfi_param_page:
 302         kfree(p);
 303
 304         return ret;
 305 }