drivers/mtd/nand/raw/nandsim.c

   1 /*
   2  * NAND flash simulator.
   3  *
   4  * Author: Artem B. Bityuckiy <dedekind@oktetlabs.ru>, <dedekind@infradead.org>
   5  *
   6  * Copyright (C) 2004 Nokia Corporation
   7  *
   8  * Note: NS means "NAND Simulator".
   9  * Note: Input means input TO flash chip, output means output FROM chip.
  10  *
  11  * This program is free software; you can redistribute it and/or modify it
  12  * under the terms of the GNU General Public License as published by the
  13  * Free Software Foundation; either version 2, or (at your option) any later
  14  * version.
  15  *
  16  * This program is distributed in the hope that it will be useful, but
  17  * WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
  19  * Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program; if not, write to the Free Software
  23  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA
  24  */
  25
  26 #define pr_fmt(fmt)  "[nandsim]" fmt
  27
  28 #include <linux/init.h>
  29 #include <linux/types.h>
  30 #include <linux/module.h>
  31 #include <linux/moduleparam.h>
  32 #include <linux/vmalloc.h>
  33 #include <linux/math64.h>
  34 #include <linux/slab.h>
  35 #include <linux/errno.h>
  36 #include <linux/string.h>
  37 #include <linux/mtd/mtd.h>
  38 #include <linux/mtd/rawnand.h>
  39 #include <linux/mtd/nand_bch.h>
  40 #include <linux/mtd/partitions.h>
  41 #include <linux/delay.h>
  42 #include <linux/list.h>
  43 #include <linux/random.h>
  44 #include <linux/sched.h>
  45 #include <linux/sched/mm.h>
  46 #include <linux/fs.h>
  47 #include <linux/pagemap.h>
  48 #include <linux/seq_file.h>
  49 #include <linux/debugfs.h>
  50
  51 /* Default simulator parameters values */
  52 #if !defined(CONFIG_NANDSIM_FIRST_ID_BYTE)  || \
  53     !defined(CONFIG_NANDSIM_SECOND_ID_BYTE) || \
  54     !defined(CONFIG_NANDSIM_THIRD_ID_BYTE)  || \
  55     !defined(CONFIG_NANDSIM_FOURTH_ID_BYTE)
  56 #define CONFIG_NANDSIM_FIRST_ID_BYTE  0x98
  57 #define CONFIG_NANDSIM_SECOND_ID_BYTE 0x39
  58 #define CONFIG_NANDSIM_THIRD_ID_BYTE  0xFF /* No byte */
  59 #define CONFIG_NANDSIM_FOURTH_ID_BYTE 0xFF /* No byte */
  60 #endif
  61
  62 #ifndef CONFIG_NANDSIM_ACCESS_DELAY
  63 #define CONFIG_NANDSIM_ACCESS_DELAY 25
  64 #endif
  65 #ifndef CONFIG_NANDSIM_PROGRAMM_DELAY
  66 #define CONFIG_NANDSIM_PROGRAMM_DELAY 200
  67 #endif
  68 #ifndef CONFIG_NANDSIM_ERASE_DELAY
  69 #define CONFIG_NANDSIM_ERASE_DELAY 2
  70 #endif
  71 #ifndef CONFIG_NANDSIM_OUTPUT_CYCLE
  72 #define CONFIG_NANDSIM_OUTPUT_CYCLE 40
  73 #endif
  74 #ifndef CONFIG_NANDSIM_INPUT_CYCLE
  75 #define CONFIG_NANDSIM_INPUT_CYCLE  50
  76 #endif
  77 #ifndef CONFIG_NANDSIM_BUS_WIDTH
  78 #define CONFIG_NANDSIM_BUS_WIDTH  8
  79 #endif
  80 #ifndef CONFIG_NANDSIM_DO_DELAYS
  81 #define CONFIG_NANDSIM_DO_DELAYS  0
  82 #endif
  83 #ifndef CONFIG_NANDSIM_LOG
  84 #define CONFIG_NANDSIM_LOG        0
  85 #endif
  86 #ifndef CONFIG_NANDSIM_DBG
  87 #define CONFIG_NANDSIM_DBG        0
  88 #endif
  89 #ifndef CONFIG_NANDSIM_MAX_PARTS
  90 #define CONFIG_NANDSIM_MAX_PARTS  32
  91 #endif
  92
  93 static uint access_delay   = CONFIG_NANDSIM_ACCESS_DELAY;
  94 static uint programm_delay = CONFIG_NANDSIM_PROGRAMM_DELAY;
  95 static uint erase_delay    = CONFIG_NANDSIM_ERASE_DELAY;
  96 static uint output_cycle   = CONFIG_NANDSIM_OUTPUT_CYCLE;
  97 static uint input_cycle    = CONFIG_NANDSIM_INPUT_CYCLE;
  98 static uint bus_width      = CONFIG_NANDSIM_BUS_WIDTH;
  99 static uint do_delays      = CONFIG_NANDSIM_DO_DELAYS;
 100 static uint log            = CONFIG_NANDSIM_LOG;
 101 static uint dbg            = CONFIG_NANDSIM_DBG;
 102 static unsigned long parts[CONFIG_NANDSIM_MAX_PARTS];
 103 static unsigned int parts_num;
 104 static char *badblocks = NULL;
 105 static char *weakblocks = NULL;
 106 static char *weakpages = NULL;
 107 static unsigned int bitflips = 0;
 108 static char *gravepages = NULL;
 109 static unsigned int overridesize = 0;
 110 static char *cache_file = NULL;
 111 static unsigned int bbt;
 112 static unsigned int bch;
 113 static u_char id_bytes[8] = {
 114         [0] = CONFIG_NANDSIM_FIRST_ID_BYTE,
 115         [1] = CONFIG_NANDSIM_SECOND_ID_BYTE,
 116         [2] = CONFIG_NANDSIM_THIRD_ID_BYTE,
 117         [3] = CONFIG_NANDSIM_FOURTH_ID_BYTE,
 118         [4 ... 7] = 0xFF,
 119 };
 120
 121 module_param_array(id_bytes, byte, NULL, 0400);
 122 module_param_named(first_id_byte, id_bytes[0], byte, 0400);
 123 module_param_named(second_id_byte, id_bytes[1], byte, 0400);
 124 module_param_named(third_id_byte, id_bytes[2], byte, 0400);
 125 module_param_named(fourth_id_byte, id_bytes[3], byte, 0400);
 126 module_param(access_delay,   uint, 0400);
 127 module_param(programm_delay, uint, 0400);
 128 module_param(erase_delay,    uint, 0400);
 129 module_param(output_cycle,   uint, 0400);
 130 module_param(input_cycle,    uint, 0400);
 131 module_param(bus_width,      uint, 0400);
 132 module_param(do_delays,      uint, 0400);
 133 module_param(log,            uint, 0400);
 134 module_param(dbg,            uint, 0400);
 135 module_param_array(parts, ulong, &parts_num, 0400);
 136 module_param(badblocks,      charp, 0400);
 137 module_param(weakblocks,     charp, 0400);
 138 module_param(weakpages,      charp, 0400);
 139 module_param(bitflips,       uint, 0400);
 140 module_param(gravepages,     charp, 0400);
 141 module_param(overridesize,   uint, 0400);
 142 module_param(cache_file,     charp, 0400);
 143 module_param(bbt,            uint, 0400);
 144 module_param(bch,            uint, 0400);
 145
 146 MODULE_PARM_DESC(id_bytes,       "The ID bytes returned by NAND Flash 'read ID' command");
 147 MODULE_PARM_DESC(first_id_byte,  "The first byte returned by NAND Flash 'read ID' command (manufacturer ID) (obsolete)");
 148 MODULE_PARM_DESC(second_id_byte, "The second byte returned by NAND Flash 'read ID' command (chip ID) (obsolete)");
 149 MODULE_PARM_DESC(third_id_byte,  "The third byte returned by NAND Flash 'read ID' command (obsolete)");
 150 MODULE_PARM_DESC(fourth_id_byte, "The fourth byte returned by NAND Flash 'read ID' command (obsolete)");
 151 MODULE_PARM_DESC(access_delay,   "Initial page access delay (microseconds)");
 152 MODULE_PARM_DESC(programm_delay, "Page programm delay (microseconds");
 153 MODULE_PARM_DESC(erase_delay,    "Sector erase delay (milliseconds)");
 154 MODULE_PARM_DESC(output_cycle,   "Word output (from flash) time (nanoseconds)");
 155 MODULE_PARM_DESC(input_cycle,    "Word input (to flash) time (nanoseconds)");
 156 MODULE_PARM_DESC(bus_width,      "Chip's bus width (8- or 16-bit)");
 157 MODULE_PARM_DESC(do_delays,      "Simulate NAND delays using busy-waits if not zero");
 158 MODULE_PARM_DESC(log,            "Perform logging if not zero");
 159 MODULE_PARM_DESC(dbg,            "Output debug information if not zero");
 160 MODULE_PARM_DESC(parts,          "Partition sizes (in erase blocks) separated by commas");
 161 /* Page and erase block positions for the following parameters are independent of any partitions */
 162 MODULE_PARM_DESC(badblocks,      "Erase blocks that are initially marked bad, separated by commas");
 163 MODULE_PARM_DESC(weakblocks,     "Weak erase blocks [: remaining erase cycles (defaults to 3)]"
 164                                  " separated by commas e.g. 113:2 means eb 113"
 165                                  " can be erased only twice before failing");
 166 MODULE_PARM_DESC(weakpages,      "Weak pages [: maximum writes (defaults to 3)]"
 167                                  " separated by commas e.g. 1401:2 means page 1401"
 168                                  " can be written only twice before failing");
 169 MODULE_PARM_DESC(bitflips,       "Maximum number of random bit flips per page (zero by default)");
 170 MODULE_PARM_DESC(gravepages,     "Pages that lose data [: maximum reads (defaults to 3)]"
 171                                  " separated by commas e.g. 1401:2 means page 1401"
 172                                  " can be read only twice before failing");
 173 MODULE_PARM_DESC(overridesize,   "Specifies the NAND Flash size overriding the ID bytes. "
 174                                  "The size is specified in erase blocks and as the exponent of a power of two"
 175                                  " e.g. 5 means a size of 32 erase blocks");
 176 MODULE_PARM_DESC(cache_file,     "File to use to cache nand pages instead of memory");
 177 MODULE_PARM_DESC(bbt,            "0 OOB, 1 BBT with marker in OOB, 2 BBT with marker in data area");
 178 MODULE_PARM_DESC(bch,            "Enable BCH ecc and set how many bits should "
 179                                  "be correctable in 512-byte blocks");
 180
 181 /* The largest possible page size */
 182 #define NS_LARGEST_PAGE_SIZE    4096
 183
 184 /* Simulator's output macros (logging, debugging, warning, error) */
 185 #define NS_LOG(args...) \
 186         do { if (log) pr_debug(" log: " args); } while(0)
 187 #define NS_DBG(args...) \
 188         do { if (dbg) pr_debug(" debug: " args); } while(0)
 189 #define NS_WARN(args...) \
 190         do { pr_warn(" warning: " args); } while(0)
 191 #define NS_ERR(args...) \
 192         do { pr_err(" error: " args); } while(0)
 193 #define NS_INFO(args...) \
 194         do { pr_info(" " args); } while(0)
 195
 196 /* Busy-wait delay macros (microseconds, milliseconds) */
 197 #define NS_UDELAY(us) \
 198         do { if (do_delays) udelay(us); } while(0)
 199 #define NS_MDELAY(us) \
 200         do { if (do_delays) mdelay(us); } while(0)
 201
 202 /* Is the nandsim structure initialized ? */
 203 #define NS_IS_INITIALIZED(ns) ((ns)->geom.totsz != 0)
 204
 205 /* Good operation completion status */
 206 #define NS_STATUS_OK(ns) (NAND_STATUS_READY | (NAND_STATUS_WP * ((ns)->lines.wp == 0)))
 207
 208 /* Operation failed completion status */
 209 #define NS_STATUS_FAILED(ns) (NAND_STATUS_FAIL | NS_STATUS_OK(ns))
 210
 211 /* Calculate the page offset in flash RAM image by (row, column) address */
 212 #define NS_RAW_OFFSET(ns) \
 213         (((ns)->regs.row * (ns)->geom.pgszoob) + (ns)->regs.column)
 214
 215 /* Calculate the OOB offset in flash RAM image by (row, column) address */
 216 #define NS_RAW_OFFSET_OOB(ns) (NS_RAW_OFFSET(ns) + ns->geom.pgsz)
 217
 218 /* After a command is input, the simulator goes to one of the following states */
 219 #define STATE_CMD_READ0        0x00000001 /* read data from the beginning of page */
 220 #define STATE_CMD_READ1        0x00000002 /* read data from the second half of page */
 221 #define STATE_CMD_READSTART    0x00000003 /* read data second command (large page devices) */
 222 #define STATE_CMD_PAGEPROG     0x00000004 /* start page program */
 223 #define STATE_CMD_READOOB      0x00000005 /* read OOB area */
 224 #define STATE_CMD_ERASE1       0x00000006 /* sector erase first command */
 225 #define STATE_CMD_STATUS       0x00000007 /* read status */
 226 #define STATE_CMD_SEQIN        0x00000009 /* sequential data input */
 227 #define STATE_CMD_READID       0x0000000A /* read ID */
 228 #define STATE_CMD_ERASE2       0x0000000B /* sector erase second command */
 229 #define STATE_CMD_RESET        0x0000000C /* reset */
 230 #define STATE_CMD_RNDOUT       0x0000000D /* random output command */
 231 #define STATE_CMD_RNDOUTSTART  0x0000000E /* random output start command */
 232 #define STATE_CMD_MASK         0x0000000F /* command states mask */
 233
 234 /* After an address is input, the simulator goes to one of these states */
 235 #define STATE_ADDR_PAGE        0x00000010 /* full (row, column) address is accepted */
 236 #define STATE_ADDR_SEC         0x00000020 /* sector address was accepted */
 237 #define STATE_ADDR_COLUMN      0x00000030 /* column address was accepted */
 238 #define STATE_ADDR_ZERO        0x00000040 /* one byte zero address was accepted */
 239 #define STATE_ADDR_MASK        0x00000070 /* address states mask */
 240
 241 /* During data input/output the simulator is in these states */
 242 #define STATE_DATAIN           0x00000100 /* waiting for data input */
 243 #define STATE_DATAIN_MASK      0x00000100 /* data input states mask */
 244
 245 #define STATE_DATAOUT          0x00001000 /* waiting for page data output */
 246 #define STATE_DATAOUT_ID       0x00002000 /* waiting for ID bytes output */
 247 #define STATE_DATAOUT_STATUS   0x00003000 /* waiting for status output */
 248 #define STATE_DATAOUT_MASK     0x00007000 /* data output states mask */
 249
 250 /* Previous operation is done, ready to accept new requests */
 251 #define STATE_READY            0x00000000
 252
 253 /* This state is used to mark that the next state isn't known yet */
 254 #define STATE_UNKNOWN          0x10000000
 255
 256 /* Simulator's actions bit masks */
 257 #define ACTION_CPY       0x00100000 /* copy page/OOB to the internal buffer */
 258 #define ACTION_PRGPAGE   0x00200000 /* program the internal buffer to flash */
 259 #define ACTION_SECERASE  0x00300000 /* erase sector */
 260 #define ACTION_ZEROOFF   0x00400000 /* don't add any offset to address */
 261 #define ACTION_HALFOFF   0x00500000 /* add to address half of page */
 262 #define ACTION_OOBOFF    0x00600000 /* add to address OOB offset */
 263 #define ACTION_MASK      0x00700000 /* action mask */
 264
 265 #define NS_OPER_NUM      13 /* Number of operations supported by the simulator */
 266 #define NS_OPER_STATES   6  /* Maximum number of states in operation */
 267
 268 #define OPT_ANY          0xFFFFFFFF /* any chip supports this operation */
 269 #define OPT_PAGE512      0x00000002 /* 512-byte  page chips */
 270 #define OPT_PAGE2048     0x00000008 /* 2048-byte page chips */
 271 #define OPT_PAGE512_8BIT 0x00000040 /* 512-byte page chips with 8-bit bus width */
 272 #define OPT_PAGE4096     0x00000080 /* 4096-byte page chips */
 273 #define OPT_LARGEPAGE    (OPT_PAGE2048 | OPT_PAGE4096) /* 2048 & 4096-byte page chips */
 274 #define OPT_SMALLPAGE    (OPT_PAGE512) /* 512-byte page chips */
 275
 276 /* Remove action bits from state */
 277 #define NS_STATE(x) ((x) & ~ACTION_MASK)
 278
 279 /*
 280  * Maximum previous states which need to be saved. Currently saving is
 281  * only needed for page program operation with preceded read command
 282  * (which is only valid for 512-byte pages).
 283  */
 284 #define NS_MAX_PREVSTATES 1
 285
 286 /* Maximum page cache pages needed to read or write a NAND page to the cache_file */
 287 #define NS_MAX_HELD_PAGES 16
 288
 289 /*
 290  * A union to represent flash memory contents and flash buffer.
 291  */
 292 union ns_mem {
 293         u_char *byte;    /* for byte access */
 294         uint16_t *word;  /* for 16-bit word access */
 295 };
 296
 297 /*
 298  * The structure which describes all the internal simulator data.
 299  */
 300 struct nandsim {
 301         struct mtd_partition partitions[CONFIG_NANDSIM_MAX_PARTS];
 302         unsigned int nbparts;
 303
 304         uint busw;              /* flash chip bus width (8 or 16) */
 305         u_char ids[8];          /* chip's ID bytes */
 306         uint32_t options;       /* chip's characteristic bits */
 307         uint32_t state;         /* current chip state */
 308         uint32_t nxstate;       /* next expected state */
 309
 310         uint32_t *op;           /* current operation, NULL operations isn't known yet  */
 311         uint32_t pstates[NS_MAX_PREVSTATES]; /* previous states */
 312         uint16_t npstates;      /* number of previous states saved */
 313         uint16_t stateidx;      /* current state index */
 314
 315         /* The simulated NAND flash pages array */
 316         union ns_mem *pages;
 317
 318         /* Slab allocator for nand pages */
 319         struct kmem_cache *nand_pages_slab;
 320
 321         /* Internal buffer of page + OOB size bytes */
 322         union ns_mem buf;
 323
 324         /* NAND flash "geometry" */
 325         struct {
 326                 uint64_t totsz;     /* total flash size, bytes */
 327                 uint32_t secsz;     /* flash sector (erase block) size, bytes */
 328                 uint pgsz;          /* NAND flash page size, bytes */
 329                 uint oobsz;         /* page OOB area size, bytes */
 330                 uint64_t totszoob;  /* total flash size including OOB, bytes */
 331                 uint pgszoob;       /* page size including OOB , bytes*/
 332                 uint secszoob;      /* sector size including OOB, bytes */
 333                 uint pgnum;         /* total number of pages */
 334                 uint pgsec;         /* number of pages per sector */
 335                 uint secshift;      /* bits number in sector size */
 336                 uint pgshift;       /* bits number in page size */
 337                 uint pgaddrbytes;   /* bytes per page address */
 338                 uint secaddrbytes;  /* bytes per sector address */
 339                 uint idbytes;       /* the number ID bytes that this chip outputs */
 340         } geom;
 341
 342         /* NAND flash internal registers */
 343         struct {
 344                 unsigned command; /* the command register */
 345                 u_char   status;  /* the status register */
 346                 uint     row;     /* the page number */
 347                 uint     column;  /* the offset within page */
 348                 uint     count;   /* internal counter */
 349                 uint     num;     /* number of bytes which must be processed */
 350                 uint     off;     /* fixed page offset */
 351         } regs;
 352
 353         /* NAND flash lines state */
 354         struct {
 355                 int ce;  /* chip Enable */
 356                 int cle; /* command Latch Enable */
 357                 int ale; /* address Latch Enable */
 358                 int wp;  /* write Protect */
 359         } lines;
 360
 361         /* Fields needed when using a cache file */
 362         struct file *cfile; /* Open file */
 363         unsigned long *pages_written; /* Which pages have been written */
 364         void *file_buf;
 365         struct page *held_pages[NS_MAX_HELD_PAGES];
 366         int held_cnt;
 367 };
 368
 369 /*
 370  * Operations array. To perform any operation the simulator must pass
 371  * through the correspondent states chain.
 372  */
 373 static struct nandsim_operations {
 374         uint32_t reqopts;  /* options which are required to perform the operation */
 375         uint32_t states[NS_OPER_STATES]; /* operation's states */
 376 } ops[NS_OPER_NUM] = {
 377         /* Read page + OOB from the beginning */
 378         {OPT_SMALLPAGE, {STATE_CMD_READ0 | ACTION_ZEROOFF, STATE_ADDR_PAGE | ACTION_CPY,
 379                         STATE_DATAOUT, STATE_READY}},
 380         /* Read page + OOB from the second half */
 381         {OPT_PAGE512_8BIT, {STATE_CMD_READ1 | ACTION_HALFOFF, STATE_ADDR_PAGE | ACTION_CPY,
 382                         STATE_DATAOUT, STATE_READY}},
 383         /* Read OOB */
 384         {OPT_SMALLPAGE, {STATE_CMD_READOOB | ACTION_OOBOFF, STATE_ADDR_PAGE | ACTION_CPY,
 385                         STATE_DATAOUT, STATE_READY}},
 386         /* Program page starting from the beginning */
 387         {OPT_ANY, {STATE_CMD_SEQIN, STATE_ADDR_PAGE, STATE_DATAIN,
 388                         STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},
 389         /* Program page starting from the beginning */
 390         {OPT_SMALLPAGE, {STATE_CMD_READ0, STATE_CMD_SEQIN | ACTION_ZEROOFF, STATE_ADDR_PAGE,
 391                               STATE_DATAIN, STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},
 392         /* Program page starting from the second half */
 393         {OPT_PAGE512, {STATE_CMD_READ1, STATE_CMD_SEQIN | ACTION_HALFOFF, STATE_ADDR_PAGE,
 394                               STATE_DATAIN, STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},
 395         /* Program OOB */
 396         {OPT_SMALLPAGE, {STATE_CMD_READOOB, STATE_CMD_SEQIN | ACTION_OOBOFF, STATE_ADDR_PAGE,
 397                               STATE_DATAIN, STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},
 398         /* Erase sector */
 399         {OPT_ANY, {STATE_CMD_ERASE1, STATE_ADDR_SEC, STATE_CMD_ERASE2 | ACTION_SECERASE, STATE_READY}},
 400         /* Read status */
 401         {OPT_ANY, {STATE_CMD_STATUS, STATE_DATAOUT_STATUS, STATE_READY}},
 402         /* Read ID */
 403         {OPT_ANY, {STATE_CMD_READID, STATE_ADDR_ZERO, STATE_DATAOUT_ID, STATE_READY}},
 404         /* Large page devices read page */
 405         {OPT_LARGEPAGE, {STATE_CMD_READ0, STATE_ADDR_PAGE, STATE_CMD_READSTART | ACTION_CPY,
 406                                STATE_DATAOUT, STATE_READY}},
 407         /* Large page devices random page read */
 408         {OPT_LARGEPAGE, {STATE_CMD_RNDOUT, STATE_ADDR_COLUMN, STATE_CMD_RNDOUTSTART | ACTION_CPY,
 409                                STATE_DATAOUT, STATE_READY}},
 410 };
 411
 412 struct weak_block {
 413         struct list_head list;
 414         unsigned int erase_block_no;
 415         unsigned int max_erases;
 416         unsigned int erases_done;
 417 };
 418
 419 static LIST_HEAD(weak_blocks);
 420
 421 struct weak_page {
 422         struct list_head list;
 423         unsigned int page_no;
 424         unsigned int max_writes;
 425         unsigned int writes_done;
 426 };
 427
 428 static LIST_HEAD(weak_pages);
 429
 430 struct grave_page {
 431         struct list_head list;
 432         unsigned int page_no;
 433         unsigned int max_reads;
 434         unsigned int reads_done;
 435 };
 436
 437 static LIST_HEAD(grave_pages);
 438
 439 static unsigned long *erase_block_wear = NULL;
 440 static unsigned int wear_eb_count = 0;
 441 static unsigned long total_wear = 0;
 442
 443 /* MTD structure for NAND controller */
 444 static struct mtd_info *nsmtd;
 445
 446 static int nandsim_debugfs_show(struct seq_file *m, void *private)
 447 {
 448         unsigned long wmin = -1, wmax = 0, avg;
 449         unsigned long deciles[10], decile_max[10], tot = 0;
 450         unsigned int i;
 451
 452         /* Calc wear stats */
 453         for (i = 0; i < wear_eb_count; ++i) {
 454                 unsigned long wear = erase_block_wear[i];
 455                 if (wear < wmin)
 456                         wmin = wear;
 457                 if (wear > wmax)
 458                         wmax = wear;
 459                 tot += wear;
 460         }
 461
 462         for (i = 0; i < 9; ++i) {
 463                 deciles[i] = 0;
 464                 decile_max[i] = (wmax * (i + 1) + 5) / 10;
 465         }
 466         deciles[9] = 0;
 467         decile_max[9] = wmax;
 468         for (i = 0; i < wear_eb_count; ++i) {
 469                 int d;
 470                 unsigned long wear = erase_block_wear[i];
 471                 for (d = 0; d < 10; ++d)
 472                         if (wear <= decile_max[d]) {
 473                                 deciles[d] += 1;
 474                                 break;
 475                         }
 476         }
 477         avg = tot / wear_eb_count;
 478
 479         /* Output wear report */
 480         seq_printf(m, "Total numbers of erases:  %lu\n", tot);
 481         seq_printf(m, "Number of erase blocks:   %u\n", wear_eb_count);
 482         seq_printf(m, "Average number of erases: %lu\n", avg);
 483         seq_printf(m, "Maximum number of erases: %lu\n", wmax);
 484         seq_printf(m, "Minimum number of erases: %lu\n", wmin);
 485         for (i = 0; i < 10; ++i) {
 486                 unsigned long from = (i ? decile_max[i - 1] + 1 : 0);
 487                 if (from > decile_max[i])
 488                         continue;
 489                 seq_printf(m, "Number of ebs with erase counts from %lu to %lu : %lu\n",
 490                         from,
 491                         decile_max[i],
 492                         deciles[i]);
 493         }
 494
 495         return 0;
 496 }
 497
 498 static int nandsim_debugfs_open(struct inode *inode, struct file *file)
 499 {
 500         return single_open(file, nandsim_debugfs_show, inode->i_private);
 501 }
 502
 503 static const struct file_operations dfs_fops = {
 504         .open           = nandsim_debugfs_open,
 505         .read           = seq_read,
 506         .llseek         = seq_lseek,
 507         .release        = single_release,
 508 };
 509
 510 /**
 511  * nandsim_debugfs_create - initialize debugfs
 512  * @dev: nandsim device description object
 513  *
 514  * This function creates all debugfs files for UBI device @ubi. Returns zero in
 515  * case of success and a negative error code in case of failure.
 516  */
 517 static int nandsim_debugfs_create(struct nandsim *dev)
 518 {
 519         struct dentry *root = nsmtd->dbg.dfs_dir;
 520         struct dentry *dent;
 521
 522         /*
 523          * Just skip debugfs initialization when the debugfs directory is
 524          * missing.
 525          */
 526         if (IS_ERR_OR_NULL(root)) {
 527                 if (IS_ENABLED(CONFIG_DEBUG_FS) &&
 528                     !IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER))
 529                         NS_WARN("CONFIG_MTD_PARTITIONED_MASTER must be enabled to expose debugfs stuff\n");
 530                 return 0;
 531         }
 532
 533         dent = debugfs_create_file("nandsim_wear_report", S_IRUSR,
 534                                    root, dev, &dfs_fops);
 535         if (IS_ERR_OR_NULL(dent)) {
 536                 NS_ERR("cannot create \"nandsim_wear_report\" debugfs entry\n");
 537                 return -1;
 538         }
 539
 540         return 0;
 541 }
 542
 543 /*
 544  * Allocate array of page pointers, create slab allocation for an array
 545  * and initialize the array by NULL pointers.
 546  *
 547  * RETURNS: 0 if success, -ENOMEM if memory alloc fails.
 548  */
 549 static int __init alloc_device(struct nandsim *ns)
 550 {
 551         struct file *cfile;
 552         int i, err;
 553
 554         if (cache_file) {
 555                 cfile = filp_open(cache_file, O_CREAT | O_RDWR | O_LARGEFILE, 0600);
 556                 if (IS_ERR(cfile))
 557                         return PTR_ERR(cfile);
 558                 if (!(cfile->f_mode & FMODE_CAN_READ)) {
 559                         NS_ERR("alloc_device: cache file not readable\n");
 560                         err = -EINVAL;
 561                         goto err_close;
 562                 }
 563                 if (!(cfile->f_mode & FMODE_CAN_WRITE)) {
 564                         NS_ERR("alloc_device: cache file not writeable\n");
 565                         err = -EINVAL;
 566                         goto err_close;
 567                 }
 568                 ns->pages_written = vzalloc(BITS_TO_LONGS(ns->geom.pgnum) *
 569                                             sizeof(unsigned long));
 570                 if (!ns->pages_written) {
 571                         NS_ERR("alloc_device: unable to allocate pages written array\n");
 572                         err = -ENOMEM;
 573                         goto err_close;
 574                 }
 575                 ns->file_buf = kmalloc(ns->geom.pgszoob, GFP_KERNEL);
 576                 if (!ns->file_buf) {
 577                         NS_ERR("alloc_device: unable to allocate file buf\n");
 578                         err = -ENOMEM;
 579                         goto err_free;
 580                 }
 581                 ns->cfile = cfile;
 582                 return 0;
 583         }
 584
 585         ns->pages = vmalloc(array_size(sizeof(union ns_mem), ns->geom.pgnum));
 586         if (!ns->pages) {
 587                 NS_ERR("alloc_device: unable to allocate page array\n");
 588                 return -ENOMEM;
 589         }
 590         for (i = 0; i < ns->geom.pgnum; i++) {
 591                 ns->pages[i].byte = NULL;
 592         }
 593         ns->nand_pages_slab = kmem_cache_create("nandsim",
 594                                                 ns->geom.pgszoob, 0, 0, NULL);
 595         if (!ns->nand_pages_slab) {
 596                 NS_ERR("cache_create: unable to create kmem_cache\n");
 597                 return -ENOMEM;
 598         }
 599
 600         return 0;
 601
 602 err_free:
 603         vfree(ns->pages_written);
 604 err_close:
 605         filp_close(cfile, NULL);
 606         return err;
 607 }
 608
 609 /*
 610  * Free any allocated pages, and free the array of page pointers.
 611  */
 612 static void free_device(struct nandsim *ns)
 613 {
 614         int i;
 615
 616         if (ns->cfile) {
 617                 kfree(ns->file_buf);
 618                 vfree(ns->pages_written);
 619                 filp_close(ns->cfile, NULL);
 620                 return;
 621         }
 622
 623         if (ns->pages) {
 624                 for (i = 0; i < ns->geom.pgnum; i++) {
 625                         if (ns->pages[i].byte)
 626                                 kmem_cache_free(ns->nand_pages_slab,
 627                                                 ns->pages[i].byte);
 628                 }
 629                 kmem_cache_destroy(ns->nand_pages_slab);
 630                 vfree(ns->pages);
 631         }
 632 }
 633
 634 static char __init *get_partition_name(int i)
 635 {
 636         return kasprintf(GFP_KERNEL, "NAND simulator partition %d", i);
 637 }
 638
 639 /*
 640  * Initialize the nandsim structure.
 641  *
 642  * RETURNS: 0 if success, -ERRNO if failure.
 643  */
 644 static int __init init_nandsim(struct mtd_info *mtd)
 645 {
 646         struct nand_chip *chip = mtd_to_nand(mtd);
 647         struct nandsim   *ns   = nand_get_controller_data(chip);
 648         int i, ret = 0;
 649         uint64_t remains;
 650         uint64_t next_offset;
 651
 652         if (NS_IS_INITIALIZED(ns)) {
 653                 NS_ERR("init_nandsim: nandsim is already initialized\n");
 654                 return -EIO;
 655         }
 656
 657         /* Force mtd to not do delays */
 658         chip->chip_delay = 0;
 659
 660         /* Initialize the NAND flash parameters */
 661         ns->busw = chip->options & NAND_BUSWIDTH_16 ? 16 : 8;
 662         ns->geom.totsz    = mtd->size;
 663         ns->geom.pgsz     = mtd->writesize;
 664         ns->geom.oobsz    = mtd->oobsize;
 665         ns->geom.secsz    = mtd->erasesize;
 666         ns->geom.pgszoob  = ns->geom.pgsz + ns->geom.oobsz;
 667         ns->geom.pgnum    = div_u64(ns->geom.totsz, ns->geom.pgsz);
 668         ns->geom.totszoob = ns->geom.totsz + (uint64_t)ns->geom.pgnum * ns->geom.oobsz;
 669         ns->geom.secshift = ffs(ns->geom.secsz) - 1;
 670         ns->geom.pgshift  = chip->page_shift;
 671         ns->geom.pgsec    = ns->geom.secsz / ns->geom.pgsz;
 672         ns->geom.secszoob = ns->geom.secsz + ns->geom.oobsz * ns->geom.pgsec;
 673         ns->options = 0;
 674
 675         if (ns->geom.pgsz == 512) {
 676                 ns->options |= OPT_PAGE512;
 677                 if (ns->busw == 8)
 678                         ns->options |= OPT_PAGE512_8BIT;
 679         } else if (ns->geom.pgsz == 2048) {
 680                 ns->options |= OPT_PAGE2048;
 681         } else if (ns->geom.pgsz == 4096) {
 682                 ns->options |= OPT_PAGE4096;
 683         } else {
 684                 NS_ERR("init_nandsim: unknown page size %u\n", ns->geom.pgsz);
 685                 return -EIO;
 686         }
 687
 688         if (ns->options & OPT_SMALLPAGE) {
 689                 if (ns->geom.totsz <= (32 << 20)) {
 690                         ns->geom.pgaddrbytes  = 3;
 691                         ns->geom.secaddrbytes = 2;
 692                 } else {
 693                         ns->geom.pgaddrbytes  = 4;
 694                         ns->geom.secaddrbytes = 3;
 695                 }
 696         } else {
 697                 if (ns->geom.totsz <= (128 << 20)) {
 698                         ns->geom.pgaddrbytes  = 4;
 699                         ns->geom.secaddrbytes = 2;
 700                 } else {
 701                         ns->geom.pgaddrbytes  = 5;
 702                         ns->geom.secaddrbytes = 3;
 703                 }
 704         }
 705
 706         /* Fill the partition_info structure */
 707         if (parts_num > ARRAY_SIZE(ns->partitions)) {
 708                 NS_ERR("too many partitions.\n");
 709                 return -EINVAL;
 710         }
 711         remains = ns->geom.totsz;
 712         next_offset = 0;
 713         for (i = 0; i < parts_num; ++i) {
 714                 uint64_t part_sz = (uint64_t)parts[i] * ns->geom.secsz;
 715
 716                 if (!part_sz || part_sz > remains) {
 717                         NS_ERR("bad partition size.\n");
 718                         return -EINVAL;
 719                 }
 720                 ns->partitions[i].name   = get_partition_name(i);
 721                 if (!ns->partitions[i].name) {
 722                         NS_ERR("unable to allocate memory.\n");
 723                         return -ENOMEM;
 724                 }
 725                 ns->partitions[i].offset = next_offset;
 726                 ns->partitions[i].size   = part_sz;
 727                 next_offset += ns->partitions[i].size;
 728                 remains -= ns->partitions[i].size;
 729         }
 730         ns->nbparts = parts_num;
 731         if (remains) {
 732                 if (parts_num + 1 > ARRAY_SIZE(ns->partitions)) {
 733                         NS_ERR("too many partitions.\n");
 734                         return -EINVAL;
 735                 }
 736                 ns->partitions[i].name   = get_partition_name(i);
 737                 if (!ns->partitions[i].name) {
 738                         NS_ERR("unable to allocate memory.\n");
 739                         return -ENOMEM;
 740                 }
 741                 ns->partitions[i].offset = next_offset;
 742                 ns->partitions[i].size   = remains;
 743                 ns->nbparts += 1;
 744         }
 745
 746         if (ns->busw == 16)
 747                 NS_WARN("16-bit flashes support wasn't tested\n");
 748
 749         printk("flash size: %llu MiB\n",
 750                         (unsigned long long)ns->geom.totsz >> 20);
 751         printk("page size: %u bytes\n",         ns->geom.pgsz);
 752         printk("OOB area size: %u bytes\n",     ns->geom.oobsz);
 753         printk("sector size: %u KiB\n",         ns->geom.secsz >> 10);
 754         printk("pages number: %u\n",            ns->geom.pgnum);
 755         printk("pages per sector: %u\n",        ns->geom.pgsec);
 756         printk("bus width: %u\n",               ns->busw);
 757         printk("bits in sector size: %u\n",     ns->geom.secshift);
 758         printk("bits in page size: %u\n",       ns->geom.pgshift);
 759         printk("bits in OOB size: %u\n",        ffs(ns->geom.oobsz) - 1);
 760         printk("flash size with OOB: %llu KiB\n",
 761                         (unsigned long long)ns->geom.totszoob >> 10);
 762         printk("page address bytes: %u\n",      ns->geom.pgaddrbytes);
 763         printk("sector address bytes: %u\n",    ns->geom.secaddrbytes);
 764         printk("options: %#x\n",                ns->options);
 765
 766         if ((ret = alloc_device(ns)) != 0)
 767                 return ret;
 768
 769         /* Allocate / initialize the internal buffer */
 770         ns->buf.byte = kmalloc(ns->geom.pgszoob, GFP_KERNEL);
 771         if (!ns->buf.byte) {
 772                 NS_ERR("init_nandsim: unable to allocate %u bytes for the internal buffer\n",
 773                         ns->geom.pgszoob);
 774                 return -ENOMEM;
 775         }
 776         memset(ns->buf.byte, 0xFF, ns->geom.pgszoob);
 777
 778         return 0;
 779 }
 780
 781 /*
 782  * Free the nandsim structure.
 783  */
 784 static void free_nandsim(struct nandsim *ns)
 785 {
 786         kfree(ns->buf.byte);
 787         free_device(ns);
 788
 789         return;
 790 }
 791
 792 static int parse_badblocks(struct nandsim *ns, struct mtd_info *mtd)
 793 {
 794         char *w;
 795         int zero_ok;
 796         unsigned int erase_block_no;
 797         loff_t offset;
 798
 799         if (!badblocks)
 800                 return 0;
 801         w = badblocks;
 802         do {
 803                 zero_ok = (*w == '0' ? 1 : 0);
 804                 erase_block_no = simple_strtoul(w, &w, 0);
 805                 if (!zero_ok && !erase_block_no) {
 806                         NS_ERR("invalid badblocks.\n");
 807                         return -EINVAL;
 808                 }
 809                 offset = (loff_t)erase_block_no * ns->geom.secsz;
 810                 if (mtd_block_markbad(mtd, offset)) {
 811                         NS_ERR("invalid badblocks.\n");
 812                         return -EINVAL;
 813                 }
 814                 if (*w == ',')
 815                         w += 1;
 816         } while (*w);
 817         return 0;
 818 }
 819
 820 static int parse_weakblocks(void)
 821 {
 822         char *w;
 823         int zero_ok;
 824         unsigned int erase_block_no;
 825         unsigned int max_erases;
 826         struct weak_block *wb;
 827
 828         if (!weakblocks)
 829                 return 0;
 830         w = weakblocks;
 831         do {
 832                 zero_ok = (*w == '0' ? 1 : 0);
 833                 erase_block_no = simple_strtoul(w, &w, 0);
 834                 if (!zero_ok && !erase_block_no) {
 835                         NS_ERR("invalid weakblocks.\n");
 836                         return -EINVAL;
 837                 }
 838                 max_erases = 3;
 839                 if (*w == ':') {
 840                         w += 1;
 841                         max_erases = simple_strtoul(w, &w, 0);
 842                 }
 843                 if (*w == ',')
 844                         w += 1;
 845                 wb = kzalloc(sizeof(*wb), GFP_KERNEL);
 846                 if (!wb) {
 847                         NS_ERR("unable to allocate memory.\n");
 848                         return -ENOMEM;
 849                 }
 850                 wb->erase_block_no = erase_block_no;
 851                 wb->max_erases = max_erases;
 852                 list_add(&wb->list, &weak_blocks);
 853         } while (*w);
 854         return 0;
 855 }
 856
 857 static int erase_error(unsigned int erase_block_no)
 858 {
 859         struct weak_block *wb;
 860
 861         list_for_each_entry(wb, &weak_blocks, list)
 862                 if (wb->erase_block_no == erase_block_no) {
 863                         if (wb->erases_done >= wb->max_erases)
 864                                 return 1;
 865                         wb->erases_done += 1;
 866                         return 0;
 867                 }
 868         return 0;
 869 }
 870
 871 static int parse_weakpages(void)
 872 {
 873         char *w;
 874         int zero_ok;
 875         unsigned int page_no;
 876         unsigned int max_writes;
 877         struct weak_page *wp;
 878
 879         if (!weakpages)
 880                 return 0;
 881         w = weakpages;
 882         do {
 883                 zero_ok = (*w == '0' ? 1 : 0);
 884                 page_no = simple_strtoul(w, &w, 0);
 885                 if (!zero_ok && !page_no) {
 886                         NS_ERR("invalid weakpages.\n");
 887                         return -EINVAL;
 888                 }
 889                 max_writes = 3;
 890                 if (*w == ':') {
 891                         w += 1;
 892                         max_writes = simple_strtoul(w, &w, 0);
 893                 }
 894                 if (*w == ',')
 895                         w += 1;
 896                 wp = kzalloc(sizeof(*wp), GFP_KERNEL);
 897                 if (!wp) {
 898                         NS_ERR("unable to allocate memory.\n");
 899                         return -ENOMEM;
 900                 }
 901                 wp->page_no = page_no;
 902                 wp->max_writes = max_writes;
 903                 list_add(&wp->list, &weak_pages);
 904         } while (*w);
 905         return 0;
 906 }
 907
 908 static int write_error(unsigned int page_no)
 909 {
 910         struct weak_page *wp;
 911
 912         list_for_each_entry(wp, &weak_pages, list)
 913                 if (wp->page_no == page_no) {
 914                         if (wp->writes_done >= wp->max_writes)
 915                                 return 1;
 916                         wp->writes_done += 1;
 917                         return 0;
 918                 }
 919         return 0;
 920 }
 921
 922 static int parse_gravepages(void)
 923 {
 924         char *g;
 925         int zero_ok;
 926         unsigned int page_no;
 927         unsigned int max_reads;
 928         struct grave_page *gp;
 929
 930         if (!gravepages)
 931                 return 0;
 932         g = gravepages;
 933         do {
 934                 zero_ok = (*g == '0' ? 1 : 0);
 935                 page_no = simple_strtoul(g, &g, 0);
 936                 if (!zero_ok && !page_no) {
 937                         NS_ERR("invalid gravepagess.\n");
 938                         return -EINVAL;
 939                 }
 940                 max_reads = 3;
 941                 if (*g == ':') {
 942                         g += 1;
 943                         max_reads = simple_strtoul(g, &g, 0);
 944                 }
 945                 if (*g == ',')
 946                         g += 1;
 947                 gp = kzalloc(sizeof(*gp), GFP_KERNEL);
 948                 if (!gp) {
 949                         NS_ERR("unable to allocate memory.\n");
 950                         return -ENOMEM;
 951                 }
 952                 gp->page_no = page_no;
 953                 gp->max_reads = max_reads;
 954                 list_add(&gp->list, &grave_pages);
 955         } while (*g);
 956         return 0;
 957 }
 958
 959 static int read_error(unsigned int page_no)
 960 {
 961         struct grave_page *gp;
 962
 963         list_for_each_entry(gp, &grave_pages, list)
 964                 if (gp->page_no == page_no) {
 965                         if (gp->reads_done >= gp->max_reads)
 966                                 return 1;
 967                         gp->reads_done += 1;
 968                         return 0;
 969                 }
 970         return 0;
 971 }
 972
 973 static void free_lists(void)
 974 {
 975         struct list_head *pos, *n;
 976         list_for_each_safe(pos, n, &weak_blocks) {
 977                 list_del(pos);
 978                 kfree(list_entry(pos, struct weak_block, list));
 979         }
 980         list_for_each_safe(pos, n, &weak_pages) {
 981                 list_del(pos);
 982                 kfree(list_entry(pos, struct weak_page, list));
 983         }
 984         list_for_each_safe(pos, n, &grave_pages) {
 985                 list_del(pos);
 986                 kfree(list_entry(pos, struct grave_page, list));
 987         }
 988         kfree(erase_block_wear);
 989 }
 990
 991 static int setup_wear_reporting(struct mtd_info *mtd)
 992 {
 993         size_t mem;
 994
 995         wear_eb_count = div_u64(mtd->size, mtd->erasesize);
 996         mem = wear_eb_count * sizeof(unsigned long);
 997         if (mem / sizeof(unsigned long) != wear_eb_count) {
 998                 NS_ERR("Too many erase blocks for wear reporting\n");
 999                 return -ENOMEM;
1000         }
1001         erase_block_wear = kzalloc(mem, GFP_KERNEL);
1002         if (!erase_block_wear) {
1003                 NS_ERR("Too many erase blocks for wear reporting\n");
1004                 return -ENOMEM;
1005         }
1006         return 0;
1007 }
1008
1009 static void update_wear(unsigned int erase_block_no)
1010 {
1011         if (!erase_block_wear)
1012                 return;
1013         total_wear += 1;
1014         /*
1015          * TODO: Notify this through a debugfs entry,
1016          * instead of showing an error message.
1017          */
1018         if (total_wear == 0)
1019                 NS_ERR("Erase counter total overflow\n");
1020         erase_block_wear[erase_block_no] += 1;
1021         if (erase_block_wear[erase_block_no] == 0)
1022                 NS_ERR("Erase counter overflow for erase block %u\n", erase_block_no);
1023 }
1024
1025 /*
1026  * Returns the string representation of 'state' state.
1027  */
1028 static char *get_state_name(uint32_t state)
1029 {
1030         switch (NS_STATE(state)) {
1031                 case STATE_CMD_READ0:
1032                         return "STATE_CMD_READ0";
1033                 case STATE_CMD_READ1:
1034                         return "STATE_CMD_READ1";
1035                 case STATE_CMD_PAGEPROG:
1036                         return "STATE_CMD_PAGEPROG";
1037                 case STATE_CMD_READOOB:
1038                         return "STATE_CMD_READOOB";
1039                 case STATE_CMD_READSTART:
1040                         return "STATE_CMD_READSTART";
1041                 case STATE_CMD_ERASE1:
1042                         return "STATE_CMD_ERASE1";
1043                 case STATE_CMD_STATUS:
1044                         return "STATE_CMD_STATUS";
1045                 case STATE_CMD_SEQIN:
1046                         return "STATE_CMD_SEQIN";
1047                 case STATE_CMD_READID:
1048                         return "STATE_CMD_READID";
1049                 case STATE_CMD_ERASE2:
1050                         return "STATE_CMD_ERASE2";
1051                 case STATE_CMD_RESET:
1052                         return "STATE_CMD_RESET";
1053                 case STATE_CMD_RNDOUT:
1054                         return "STATE_CMD_RNDOUT";
1055                 case STATE_CMD_RNDOUTSTART:
1056                         return "STATE_CMD_RNDOUTSTART";
1057                 case STATE_ADDR_PAGE:
1058                         return "STATE_ADDR_PAGE";
1059                 case STATE_ADDR_SEC:
1060                         return "STATE_ADDR_SEC";
1061                 case STATE_ADDR_ZERO:
1062                         return "STATE_ADDR_ZERO";
1063                 case STATE_ADDR_COLUMN:
1064                         return "STATE_ADDR_COLUMN";
1065                 case STATE_DATAIN:
1066                         return "STATE_DATAIN";
1067                 case STATE_DATAOUT:
1068                         return "STATE_DATAOUT";
1069                 case STATE_DATAOUT_ID:
1070                         return "STATE_DATAOUT_ID";
1071                 case STATE_DATAOUT_STATUS:
1072                         return "STATE_DATAOUT_STATUS";
1073                 case STATE_READY:
1074                         return "STATE_READY";
1075                 case STATE_UNKNOWN:
1076                         return "STATE_UNKNOWN";
1077         }
1078
1079         NS_ERR("get_state_name: unknown state, BUG\n");
1080         return NULL;
1081 }
1082
1083 /*
1084  * Check if command is valid.
1085  *
1086  * RETURNS: 1 if wrong command, 0 if right.
1087  */
1088 static int check_command(int cmd)
1089 {
1090         switch (cmd) {
1091
1092         case NAND_CMD_READ0:
1093         case NAND_CMD_READ1:
1094         case NAND_CMD_READSTART:
1095         case NAND_CMD_PAGEPROG:
1096         case NAND_CMD_READOOB:
1097         case NAND_CMD_ERASE1:
1098         case NAND_CMD_STATUS:
1099         case NAND_CMD_SEQIN:
1100         case NAND_CMD_READID:
1101         case NAND_CMD_ERASE2:
1102         case NAND_CMD_RESET:
1103         case NAND_CMD_RNDOUT:
1104         case NAND_CMD_RNDOUTSTART:
1105                 return 0;
1106
1107         default:
1108                 return 1;
1109         }
1110 }
1111
1112 /*
1113  * Returns state after command is accepted by command number.
1114  */
1115 static uint32_t get_state_by_command(unsigned command)
1116 {
1117         switch (command) {
1118                 case NAND_CMD_READ0:
1119                         return STATE_CMD_READ0;
1120                 case NAND_CMD_READ1:
1121                         return STATE_CMD_READ1;
1122                 case NAND_CMD_PAGEPROG:
1123                         return STATE_CMD_PAGEPROG;
1124                 case NAND_CMD_READSTART:
1125                         return STATE_CMD_READSTART;
1126                 case NAND_CMD_READOOB:
1127                         return STATE_CMD_READOOB;
1128                 case NAND_CMD_ERASE1:
1129                         return STATE_CMD_ERASE1;
1130                 case NAND_CMD_STATUS:
1131                         return STATE_CMD_STATUS;
1132                 case NAND_CMD_SEQIN:
1133                         return STATE_CMD_SEQIN;
1134                 case NAND_CMD_READID:
1135                         return STATE_CMD_READID;
1136                 case NAND_CMD_ERASE2:
1137                         return STATE_CMD_ERASE2;
1138                 case NAND_CMD_RESET:
1139                         return STATE_CMD_RESET;
1140                 case NAND_CMD_RNDOUT:
1141                         return STATE_CMD_RNDOUT;
1142                 case NAND_CMD_RNDOUTSTART:
1143                         return STATE_CMD_RNDOUTSTART;
1144         }
1145
1146         NS_ERR("get_state_by_command: unknown command, BUG\n");
1147         return 0;
1148 }
1149
1150 /*
1151  * Move an address byte to the correspondent internal register.
1152  */
1153 static inline void accept_addr_byte(struct nandsim *ns, u_char bt)
1154 {
1155         uint byte = (uint)bt;
1156
1157         if (ns->regs.count < (ns->geom.pgaddrbytes - ns->geom.secaddrbytes))
1158                 ns->regs.column |= (byte << 8 * ns->regs.count);
1159         else {
1160                 ns->regs.row |= (byte << 8 * (ns->regs.count -
1161                                                 ns->geom.pgaddrbytes +
1162                                                 ns->geom.secaddrbytes));
1163         }
1164
1165         return;
1166 }
1167
1168 /*
1169  * Switch to STATE_READY state.
1170  */
1171 static inline void switch_to_ready_state(struct nandsim *ns, u_char status)
1172 {
1173         NS_DBG("switch_to_ready_state: switch to %s state\n", get_state_name(STATE_READY));
1174
1175         ns->state       = STATE_READY;
1176         ns->nxstate     = STATE_UNKNOWN;
1177         ns->op          = NULL;
1178         ns->npstates    = 0;
1179         ns->stateidx    = 0;
1180         ns->regs.num    = 0;
1181         ns->regs.count  = 0;
1182         ns->regs.off    = 0;
1183         ns->regs.row    = 0;
1184         ns->regs.column = 0;
1185         ns->regs.status = status;
1186 }
1187
1188 /*
1189  * If the operation isn't known yet, try to find it in the global array
1190  * of supported operations.
1191  *
1192  * Operation can be unknown because of the following.
1193  *   1. New command was accepted and this is the first call to find the
1194  *      correspondent states chain. In this case ns->npstates = 0;
1195  *   2. There are several operations which begin with the same command(s)
1196  *      (for example program from the second half and read from the
1197  *      second half operations both begin with the READ1 command). In this
1198  *      case the ns->pstates[] array contains previous states.
1199  *
1200  * Thus, the function tries to find operation containing the following
1201  * states (if the 'flag' parameter is 0):
1202  *    ns->pstates[0], ... ns->pstates[ns->npstates], ns->state
1203  *
1204  * If (one and only one) matching operation is found, it is accepted (
1205  * ns->ops, ns->state, ns->nxstate are initialized, ns->npstate is
1206  * zeroed).
1207  *
1208  * If there are several matches, the current state is pushed to the
1209  * ns->pstates.
1210  *
1211  * The operation can be unknown only while commands are input to the chip.
1212  * As soon as address command is accepted, the operation must be known.
1213  * In such situation the function is called with 'flag' != 0, and the
1214  * operation is searched using the following pattern:
1215  *     ns->pstates[0], ... ns->pstates[ns->npstates], <address input>
1216  *
1217  * It is supposed that this pattern must either match one operation or
1218  * none. There can't be ambiguity in that case.
1219  *
1220  * If no matches found, the function does the following:
1221  *   1. if there are saved states present, try to ignore them and search
1222  *      again only using the last command. If nothing was found, switch
1223  *      to the STATE_READY state.
1224  *   2. if there are no saved states, switch to the STATE_READY state.
1225  *
1226  * RETURNS: -2 - no matched operations found.
1227  *          -1 - several matches.
1228  *           0 - operation is found.
1229  */
1230 static int find_operation(struct nandsim *ns, uint32_t flag)
1231 {
1232         int opsfound = 0;
1233         int i, j, idx = 0;
1234
1235         for (i = 0; i < NS_OPER_NUM; i++) {
1236
1237                 int found = 1;
1238
1239                 if (!(ns->options & ops[i].reqopts))
1240                         /* Ignore operations we can't perform */
1241                         continue;
1242
1243                 if (flag) {
1244                         if (!(ops[i].states[ns->npstates] & STATE_ADDR_MASK))
1245                                 continue;
1246                 } else {
1247                         if (NS_STATE(ns->state) != NS_STATE(ops[i].states[ns->npstates]))
1248                                 continue;
1249                 }
1250
1251                 for (j = 0; j < ns->npstates; j++)
1252                         if (NS_STATE(ops[i].states[j]) != NS_STATE(ns->pstates[j])
1253                                 && (ns->options & ops[idx].reqopts)) {
1254                                 found = 0;
1255                                 break;
1256                         }
1257
1258                 if (found) {
1259                         idx = i;
1260                         opsfound += 1;
1261                 }
1262         }
1263
1264         if (opsfound == 1) {
1265                 /* Exact match */
1266                 ns->op = &ops[idx].states[0];
1267                 if (flag) {
1268                         /*
1269                          * In this case the find_operation function was
1270                          * called when address has just began input. But it isn't
1271                          * yet fully input and the current state must
1272                          * not be one of STATE_ADDR_*, but the STATE_ADDR_*
1273                          * state must be the next state (ns->nxstate).
1274                          */
1275                         ns->stateidx = ns->npstates - 1;
1276                 } else {
1277                         ns->stateidx = ns->npstates;
1278                 }
1279                 ns->npstates = 0;
1280                 ns->state = ns->op[ns->stateidx];
1281                 ns->nxstate = ns->op[ns->stateidx + 1];
1282                 NS_DBG("find_operation: operation found, index: %d, state: %s, nxstate %s\n",
1283                                 idx, get_state_name(ns->state), get_state_name(ns->nxstate));
1284                 return 0;
1285         }
1286
1287         if (opsfound == 0) {
1288                 /* Nothing was found. Try to ignore previous commands (if any) and search again */
1289                 if (ns->npstates != 0) {
1290                         NS_DBG("find_operation: no operation found, try again with state %s\n",
1291                                         get_state_name(ns->state));
1292                         ns->npstates = 0;
1293                         return find_operation(ns, 0);
1294
1295                 }
1296                 NS_DBG("find_operation: no operations found\n");
1297                 switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1298                 return -2;
1299         }
1300
1301         if (flag) {
1302                 /* This shouldn't happen */
1303                 NS_DBG("find_operation: BUG, operation must be known if address is input\n");
1304                 return -2;
1305         }
1306
1307         NS_DBG("find_operation: there is still ambiguity\n");
1308
1309         ns->pstates[ns->npstates++] = ns->state;
1310
1311         return -1;
1312 }
1313
1314 static void put_pages(struct nandsim *ns)
1315 {
1316         int i;
1317
1318         for (i = 0; i < ns->held_cnt; i++)
1319                 put_page(ns->held_pages[i]);
1320 }
1321
1322 /* Get page cache pages in advance to provide NOFS memory allocation */
1323 static int get_pages(struct nandsim *ns, struct file *file, size_t count, loff_t pos)
1324 {
1325         pgoff_t index, start_index, end_index;
1326         struct page *page;
1327         struct address_space *mapping = file->f_mapping;
1328
1329         start_index = pos >> PAGE_SHIFT;
1330         end_index = (pos + count - 1) >> PAGE_SHIFT;
1331         if (end_index - start_index + 1 > NS_MAX_HELD_PAGES)
1332                 return -EINVAL;
1333         ns->held_cnt = 0;
1334         for (index = start_index; index <= end_index; index++) {
1335                 page = find_get_page(mapping, index);
1336                 if (page == NULL) {
1337                         page = find_or_create_page(mapping, index, GFP_NOFS);
1338                         if (page == NULL) {
1339                                 write_inode_now(mapping->host, 1);
1340                                 page = find_or_create_page(mapping, index, GFP_NOFS);
1341                         }
1342                         if (page == NULL) {
1343                                 put_pages(ns);
1344                                 return -ENOMEM;
1345                         }
1346                         unlock_page(page);
1347                 }
1348                 ns->held_pages[ns->held_cnt++] = page;
1349         }
1350         return 0;
1351 }
1352
1353 static ssize_t read_file(struct nandsim *ns, struct file *file, void *buf, size_t count, loff_t pos)
1354 {
1355         ssize_t tx;
1356         int err;
1357         unsigned int noreclaim_flag;
1358
1359         err = get_pages(ns, file, count, pos);
1360         if (err)
1361                 return err;
1362         noreclaim_flag = memalloc_noreclaim_save();
1363         tx = kernel_read(file, buf, count, &pos);
1364         memalloc_noreclaim_restore(noreclaim_flag);
1365         put_pages(ns);
1366         return tx;
1367 }
1368
1369 static ssize_t write_file(struct nandsim *ns, struct file *file, void *buf, size_t count, loff_t pos)
1370 {
1371         ssize_t tx;
1372         int err;
1373         unsigned int noreclaim_flag;
1374
1375         err = get_pages(ns, file, count, pos);
1376         if (err)
1377                 return err;
1378         noreclaim_flag = memalloc_noreclaim_save();
1379         tx = kernel_write(file, buf, count, &pos);
1380         memalloc_noreclaim_restore(noreclaim_flag);
1381         put_pages(ns);
1382         return tx;
1383 }
1384
1385 /*
1386  * Returns a pointer to the current page.
1387  */
1388 static inline union ns_mem *NS_GET_PAGE(struct nandsim *ns)
1389 {
1390         return &(ns->pages[ns->regs.row]);
1391 }
1392
1393 /*
1394  * Retuns a pointer to the current byte, within the current page.
1395  */
1396 static inline u_char *NS_PAGE_BYTE_OFF(struct nandsim *ns)
1397 {
1398         return NS_GET_PAGE(ns)->byte + ns->regs.column + ns->regs.off;
1399 }
1400
1401 static int do_read_error(struct nandsim *ns, int num)
1402 {
1403         unsigned int page_no = ns->regs.row;
1404
1405         if (read_error(page_no)) {
1406                 prandom_bytes(ns->buf.byte, num);
1407                 NS_WARN("simulating read error in page %u\n", page_no);
1408                 return 1;
1409         }
1410         return 0;
1411 }
1412
1413 static void do_bit_flips(struct nandsim *ns, int num)
1414 {
1415         if (bitflips && prandom_u32() < (1 << 22)) {
1416                 int flips = 1;
1417                 if (bitflips > 1)
1418                         flips = (prandom_u32() % (int) bitflips) + 1;
1419                 while (flips--) {
1420                         int pos = prandom_u32() % (num * 8);
1421                         ns->buf.byte[pos / 8] ^= (1 << (pos % 8));
1422                         NS_WARN("read_page: flipping bit %d in page %d "
1423                                 "reading from %d ecc: corrected=%u failed=%u\n",
1424                                 pos, ns->regs.row, ns->regs.column + ns->regs.off,
1425                                 nsmtd->ecc_stats.corrected, nsmtd->ecc_stats.failed);
1426                 }
1427         }
1428 }
1429
1430 /*
1431  * Fill the NAND buffer with data read from the specified page.
1432  */
1433 static void read_page(struct nandsim *ns, int num)
1434 {
1435         union ns_mem *mypage;
1436
1437         if (ns->cfile) {
1438                 if (!test_bit(ns->regs.row, ns->pages_written)) {
1439                         NS_DBG("read_page: page %d not written\n", ns->regs.row);
1440                         memset(ns->buf.byte, 0xFF, num);
1441                 } else {
1442                         loff_t pos;
1443                         ssize_t tx;
1444
1445                         NS_DBG("read_page: page %d written, reading from %d\n",
1446                                 ns->regs.row, ns->regs.column + ns->regs.off);
1447                         if (do_read_error(ns, num))
1448                                 return;
1449                         pos = (loff_t)NS_RAW_OFFSET(ns) + ns->regs.off;
1450                         tx = read_file(ns, ns->cfile, ns->buf.byte, num, pos);
1451                         if (tx != num) {
1452                                 NS_ERR("read_page: read error for page %d ret %ld\n", ns->regs.row, (long)tx);
1453                                 return;
1454                         }
1455                         do_bit_flips(ns, num);
1456                 }
1457                 return;
1458         }
1459
1460         mypage = NS_GET_PAGE(ns);
1461         if (mypage->byte == NULL) {
1462                 NS_DBG("read_page: page %d not allocated\n", ns->regs.row);
1463                 memset(ns->buf.byte, 0xFF, num);
1464         } else {
1465                 NS_DBG("read_page: page %d allocated, reading from %d\n",
1466                         ns->regs.row, ns->regs.column + ns->regs.off);
1467                 if (do_read_error(ns, num))
1468                         return;
1469                 memcpy(ns->buf.byte, NS_PAGE_BYTE_OFF(ns), num);
1470                 do_bit_flips(ns, num);
1471         }
1472 }
1473
1474 /*
1475  * Erase all pages in the specified sector.
1476  */
1477 static void erase_sector(struct nandsim *ns)
1478 {
1479         union ns_mem *mypage;
1480         int i;
1481
1482         if (ns->cfile) {
1483                 for (i = 0; i < ns->geom.pgsec; i++)
1484                         if (__test_and_clear_bit(ns->regs.row + i,
1485                                                  ns->pages_written)) {
1486                                 NS_DBG("erase_sector: freeing page %d\n", ns->regs.row + i);
1487                         }
1488                 return;
1489         }
1490
1491         mypage = NS_GET_PAGE(ns);
1492         for (i = 0; i < ns->geom.pgsec; i++) {
1493                 if (mypage->byte != NULL) {
1494                         NS_DBG("erase_sector: freeing page %d\n", ns->regs.row+i);
1495                         kmem_cache_free(ns->nand_pages_slab, mypage->byte);
1496                         mypage->byte = NULL;
1497                 }
1498                 mypage++;
1499         }
1500 }
1501
1502 /*
1503  * Program the specified page with the contents from the NAND buffer.
1504  */
1505 static int prog_page(struct nandsim *ns, int num)
1506 {
1507         int i;
1508         union ns_mem *mypage;
1509         u_char *pg_off;
1510
1511         if (ns->cfile) {
1512                 loff_t off;
1513                 ssize_t tx;
1514                 int all;
1515
1516                 NS_DBG("prog_page: writing page %d\n", ns->regs.row);
1517                 pg_off = ns->file_buf + ns->regs.column + ns->regs.off;
1518                 off = (loff_t)NS_RAW_OFFSET(ns) + ns->regs.off;
1519                 if (!test_bit(ns->regs.row, ns->pages_written)) {
1520                         all = 1;
1521                         memset(ns->file_buf, 0xff, ns->geom.pgszoob);
1522                 } else {
1523                         all = 0;
1524                         tx = read_file(ns, ns->cfile, pg_off, num, off);
1525                         if (tx != num) {
1526                                 NS_ERR("prog_page: read error for page %d ret %ld\n", ns->regs.row, (long)tx);
1527                                 return -1;
1528                         }
1529                 }
1530                 for (i = 0; i < num; i++)
1531                         pg_off[i] &= ns->buf.byte[i];
1532                 if (all) {
1533                         loff_t pos = (loff_t)ns->regs.row * ns->geom.pgszoob;
1534                         tx = write_file(ns, ns->cfile, ns->file_buf, ns->geom.pgszoob, pos);
1535                         if (tx != ns->geom.pgszoob) {
1536                                 NS_ERR("prog_page: write error for page %d ret %ld\n", ns->regs.row, (long)tx);
1537                                 return -1;
1538                         }
1539                         __set_bit(ns->regs.row, ns->pages_written);
1540                 } else {
1541                         tx = write_file(ns, ns->cfile, pg_off, num, off);
1542                         if (tx != num) {
1543                                 NS_ERR("prog_page: write error for page %d ret %ld\n", ns->regs.row, (long)tx);
1544                                 return -1;
1545                         }
1546                 }
1547                 return 0;
1548         }
1549
1550         mypage = NS_GET_PAGE(ns);
1551         if (mypage->byte == NULL) {
1552                 NS_DBG("prog_page: allocating page %d\n", ns->regs.row);
1553                 /*
1554                  * We allocate memory with GFP_NOFS because a flash FS may
1555                  * utilize this. If it is holding an FS lock, then gets here,
1556                  * then kernel memory alloc runs writeback which goes to the FS
1557                  * again and deadlocks. This was seen in practice.
1558                  */
1559                 mypage->byte = kmem_cache_alloc(ns->nand_pages_slab, GFP_NOFS);
1560                 if (mypage->byte == NULL) {
1561                         NS_ERR("prog_page: error allocating memory for page %d\n", ns->regs.row);
1562                         return -1;
1563                 }
1564                 memset(mypage->byte, 0xFF, ns->geom.pgszoob);
1565         }
1566
1567         pg_off = NS_PAGE_BYTE_OFF(ns);
1568         for (i = 0; i < num; i++)
1569                 pg_off[i] &= ns->buf.byte[i];
1570
1571         return 0;
1572 }
1573
1574 /*
1575  * If state has any action bit, perform this action.
1576  *
1577  * RETURNS: 0 if success, -1 if error.
1578  */
1579 static int do_state_action(struct nandsim *ns, uint32_t action)
1580 {
1581         int num;
1582         int busdiv = ns->busw == 8 ? 1 : 2;
1583         unsigned int erase_block_no, page_no;
1584
1585         action &= ACTION_MASK;
1586
1587         /* Check that page address input is correct */
1588         if (action != ACTION_SECERASE && ns->regs.row >= ns->geom.pgnum) {
1589                 NS_WARN("do_state_action: wrong page number (%#x)\n", ns->regs.row);
1590                 return -1;
1591         }
1592
1593         switch (action) {
1594
1595         case ACTION_CPY:
1596                 /*
1597                  * Copy page data to the internal buffer.
1598                  */
1599
1600                 /* Column shouldn't be very large */
1601                 if (ns->regs.column >= (ns->geom.pgszoob - ns->regs.off)) {
1602                         NS_ERR("do_state_action: column number is too large\n");
1603                         break;
1604                 }
1605                 num = ns->geom.pgszoob - ns->regs.off - ns->regs.column;
1606                 read_page(ns, num);
1607
1608                 NS_DBG("do_state_action: (ACTION_CPY:) copy %d bytes to int buf, raw offset %d\n",
1609                         num, NS_RAW_OFFSET(ns) + ns->regs.off);
1610
1611                 if (ns->regs.off == 0)
1612                         NS_LOG("read page %d\n", ns->regs.row);
1613                 else if (ns->regs.off < ns->geom.pgsz)
1614                         NS_LOG("read page %d (second half)\n", ns->regs.row);
1615                 else
1616                         NS_LOG("read OOB of page %d\n", ns->regs.row);
1617
1618                 NS_UDELAY(access_delay);
1619                 NS_UDELAY(input_cycle * ns->geom.pgsz / 1000 / busdiv);
1620
1621                 break;
1622
1623         case ACTION_SECERASE:
1624                 /*
1625                  * Erase sector.
1626                  */
1627
1628                 if (ns->lines.wp) {
1629                         NS_ERR("do_state_action: device is write-protected, ignore sector erase\n");
1630                         return -1;
1631                 }
1632
1633                 if (ns->regs.row >= ns->geom.pgnum - ns->geom.pgsec
1634                         || (ns->regs.row & ~(ns->geom.secsz - 1))) {
1635                         NS_ERR("do_state_action: wrong sector address (%#x)\n", ns->regs.row);
1636                         return -1;
1637                 }
1638
1639                 ns->regs.row = (ns->regs.row <<
1640                                 8 * (ns->geom.pgaddrbytes - ns->geom.secaddrbytes)) | ns->regs.column;
1641                 ns->regs.column = 0;
1642
1643                 erase_block_no = ns->regs.row >> (ns->geom.secshift - ns->geom.pgshift);
1644
1645                 NS_DBG("do_state_action: erase sector at address %#x, off = %d\n",
1646                                 ns->regs.row, NS_RAW_OFFSET(ns));
1647                 NS_LOG("erase sector %u\n", erase_block_no);
1648
1649                 erase_sector(ns);
1650
1651                 NS_MDELAY(erase_delay);
1652
1653                 if (erase_block_wear)
1654                         update_wear(erase_block_no);
1655
1656                 if (erase_error(erase_block_no)) {
1657                         NS_WARN("simulating erase failure in erase block %u\n", erase_block_no);
1658                         return -1;
1659                 }
1660
1661                 break;
1662
1663         case ACTION_PRGPAGE:
1664                 /*
1665                  * Program page - move internal buffer data to the page.
1666                  */
1667
1668                 if (ns->lines.wp) {
1669                         NS_WARN("do_state_action: device is write-protected, programm\n");
1670                         return -1;
1671                 }
1672
1673                 num = ns->geom.pgszoob - ns->regs.off - ns->regs.column;
1674                 if (num != ns->regs.count) {
1675                         NS_ERR("do_state_action: too few bytes were input (%d instead of %d)\n",
1676                                         ns->regs.count, num);
1677                         return -1;
1678                 }
1679
1680                 if (prog_page(ns, num) == -1)
1681                         return -1;
1682
1683                 page_no = ns->regs.row;
1684
1685                 NS_DBG("do_state_action: copy %d bytes from int buf to (%#x, %#x), raw off = %d\n",
1686                         num, ns->regs.row, ns->regs.column, NS_RAW_OFFSET(ns) + ns->regs.off);
1687                 NS_LOG("programm page %d\n", ns->regs.row);
1688
1689                 NS_UDELAY(programm_delay);
1690                 NS_UDELAY(output_cycle * ns->geom.pgsz / 1000 / busdiv);
1691
1692                 if (write_error(page_no)) {
1693                         NS_WARN("simulating write failure in page %u\n", page_no);
1694                         return -1;
1695                 }
1696
1697                 break;
1698
1699         case ACTION_ZEROOFF:
1700                 NS_DBG("do_state_action: set internal offset to 0\n");
1701                 ns->regs.off = 0;
1702                 break;
1703
1704         case ACTION_HALFOFF:
1705                 if (!(ns->options & OPT_PAGE512_8BIT)) {
1706                         NS_ERR("do_state_action: BUG! can't skip half of page for non-512"
1707                                 "byte page size 8x chips\n");
1708                         return -1;
1709                 }
1710                 NS_DBG("do_state_action: set internal offset to %d\n", ns->geom.pgsz/2);
1711                 ns->regs.off = ns->geom.pgsz/2;
1712                 break;
1713
1714         case ACTION_OOBOFF:
1715                 NS_DBG("do_state_action: set internal offset to %d\n", ns->geom.pgsz);
1716                 ns->regs.off = ns->geom.pgsz;
1717                 break;
1718
1719         default:
1720                 NS_DBG("do_state_action: BUG! unknown action\n");
1721         }
1722
1723         return 0;
1724 }
1725
1726 /*
1727  * Switch simulator's state.
1728  */
1729 static void switch_state(struct nandsim *ns)
1730 {
1731         if (ns->op) {
1732                 /*
1733                  * The current operation have already been identified.
1734                  * Just follow the states chain.
1735                  */
1736
1737                 ns->stateidx += 1;
1738                 ns->state = ns->nxstate;
1739                 ns->nxstate = ns->op[ns->stateidx + 1];
1740
1741                 NS_DBG("switch_state: operation is known, switch to the next state, "
1742                         "state: %s, nxstate: %s\n",
1743                         get_state_name(ns->state), get_state_name(ns->nxstate));
1744
1745                 /* See, whether we need to do some action */
1746                 if ((ns->state & ACTION_MASK) && do_state_action(ns, ns->state) < 0) {
1747                         switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1748                         return;
1749                 }
1750
1751         } else {
1752                 /*
1753                  * We don't yet know which operation we perform.
1754                  * Try to identify it.
1755                  */
1756
1757                 /*
1758                  *  The only event causing the switch_state function to
1759                  *  be called with yet unknown operation is new command.
1760                  */
1761                 ns->state = get_state_by_command(ns->regs.command);
1762
1763                 NS_DBG("switch_state: operation is unknown, try to find it\n");
1764
1765                 if (find_operation(ns, 0) != 0)
1766                         return;
1767
1768                 if ((ns->state & ACTION_MASK) && do_state_action(ns, ns->state) < 0) {
1769                         switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1770                         return;
1771                 }
1772         }
1773
1774         /* For 16x devices column means the page offset in words */
1775         if ((ns->nxstate & STATE_ADDR_MASK) && ns->busw == 16) {
1776                 NS_DBG("switch_state: double the column number for 16x device\n");
1777                 ns->regs.column <<= 1;
1778         }
1779
1780         if (NS_STATE(ns->nxstate) == STATE_READY) {
1781                 /*
1782                  * The current state is the last. Return to STATE_READY
1783                  */
1784
1785                 u_char status = NS_STATUS_OK(ns);
1786
1787                 /* In case of data states, see if all bytes were input/output */
1788                 if ((ns->state & (STATE_DATAIN_MASK | STATE_DATAOUT_MASK))
1789                         && ns->regs.count != ns->regs.num) {
1790                         NS_WARN("switch_state: not all bytes were processed, %d left\n",
1791                                         ns->regs.num - ns->regs.count);
1792                         status = NS_STATUS_FAILED(ns);
1793                 }
1794
1795                 NS_DBG("switch_state: operation complete, switch to STATE_READY state\n");
1796
1797                 switch_to_ready_state(ns, status);
1798
1799                 return;
1800         } else if (ns->nxstate & (STATE_DATAIN_MASK | STATE_DATAOUT_MASK)) {
1801                 /*
1802                  * If the next state is data input/output, switch to it now
1803                  */
1804
1805                 ns->state      = ns->nxstate;
1806                 ns->nxstate    = ns->op[++ns->stateidx + 1];
1807                 ns->regs.num   = ns->regs.count = 0;
1808
1809                 NS_DBG("switch_state: the next state is data I/O, switch, "
1810                         "state: %s, nxstate: %s\n",
1811                         get_state_name(ns->state), get_state_name(ns->nxstate));
1812
1813                 /*
1814                  * Set the internal register to the count of bytes which
1815                  * are expected to be input or output
1816                  */
1817                 switch (NS_STATE(ns->state)) {
1818                         case STATE_DATAIN:
1819                         case STATE_DATAOUT:
1820                                 ns->regs.num = ns->geom.pgszoob - ns->regs.off - ns->regs.column;
1821                                 break;
1822
1823                         case STATE_DATAOUT_ID:
1824                                 ns->regs.num = ns->geom.idbytes;
1825                                 break;
1826
1827                         case STATE_DATAOUT_STATUS:
1828                                 ns->regs.count = ns->regs.num = 0;
1829                                 break;
1830
1831                         default:
1832                                 NS_ERR("switch_state: BUG! unknown data state\n");
1833                 }
1834
1835         } else if (ns->nxstate & STATE_ADDR_MASK) {
1836                 /*
1837                  * If the next state is address input, set the internal
1838                  * register to the number of expected address bytes
1839                  */
1840
1841                 ns->regs.count = 0;
1842
1843                 switch (NS_STATE(ns->nxstate)) {
1844                         case STATE_ADDR_PAGE:
1845                                 ns->regs.num = ns->geom.pgaddrbytes;
1846
1847                                 break;
1848                         case STATE_ADDR_SEC:
1849                                 ns->regs.num = ns->geom.secaddrbytes;
1850                                 break;
1851
1852                         case STATE_ADDR_ZERO:
1853                                 ns->regs.num = 1;
1854                                 break;
1855
1856                         case STATE_ADDR_COLUMN:
1857                                 /* Column address is always 2 bytes */
1858                                 ns->regs.num = ns->geom.pgaddrbytes - ns->geom.secaddrbytes;
1859                                 break;
1860
1861                         default:
1862                                 NS_ERR("switch_state: BUG! unknown address state\n");
1863                 }
1864         } else {
1865                 /*
1866                  * Just reset internal counters.
1867                  */
1868
1869                 ns->regs.num = 0;
1870                 ns->regs.count = 0;
1871         }
1872 }
1873
1874 static u_char ns_nand_read_byte(struct mtd_info *mtd)
1875 {
1876         struct nand_chip *chip = mtd_to_nand(mtd);
1877         struct nandsim *ns = nand_get_controller_data(chip);
1878         u_char outb = 0x00;
1879
1880         /* Sanity and correctness checks */
1881         if (!ns->lines.ce) {
1882                 NS_ERR("read_byte: chip is disabled, return %#x\n", (uint)outb);
1883                 return outb;
1884         }
1885         if (ns->lines.ale || ns->lines.cle) {
1886                 NS_ERR("read_byte: ALE or CLE pin is high, return %#x\n", (uint)outb);
1887                 return outb;
1888         }
1889         if (!(ns->state & STATE_DATAOUT_MASK)) {
1890                 NS_WARN("read_byte: unexpected data output cycle, state is %s "
1891                         "return %#x\n", get_state_name(ns->state), (uint)outb);
1892                 return outb;
1893         }
1894
1895         /* Status register may be read as many times as it is wanted */
1896         if (NS_STATE(ns->state) == STATE_DATAOUT_STATUS) {
1897                 NS_DBG("read_byte: return %#x status\n", ns->regs.status);
1898                 return ns->regs.status;
1899         }
1900
1901         /* Check if there is any data in the internal buffer which may be read */
1902         if (ns->regs.count == ns->regs.num) {
1903                 NS_WARN("read_byte: no more data to output, return %#x\n", (uint)outb);
1904                 return outb;
1905         }
1906
1907         switch (NS_STATE(ns->state)) {
1908                 case STATE_DATAOUT:
1909                         if (ns->busw == 8) {
1910                                 outb = ns->buf.byte[ns->regs.count];
1911                                 ns->regs.count += 1;
1912                         } else {
1913                                 outb = (u_char)cpu_to_le16(ns->buf.word[ns->regs.count >> 1]);
1914                                 ns->regs.count += 2;
1915                         }
1916                         break;
1917                 case STATE_DATAOUT_ID:
1918                         NS_DBG("read_byte: read ID byte %d, total = %d\n", ns->regs.count, ns->regs.num);
1919                         outb = ns->ids[ns->regs.count];
1920                         ns->regs.count += 1;
1921                         break;
1922                 default:
1923                         BUG();
1924         }
1925
1926         if (ns->regs.count == ns->regs.num) {
1927                 NS_DBG("read_byte: all bytes were read\n");
1928
1929                 if (NS_STATE(ns->nxstate) == STATE_READY)
1930                         switch_state(ns);
1931         }
1932
1933         return outb;
1934 }
1935
1936 static void ns_nand_write_byte(struct mtd_info *mtd, u_char byte)
1937 {
1938         struct nand_chip *chip = mtd_to_nand(mtd);
1939         struct nandsim *ns = nand_get_controller_data(chip);
1940
1941         /* Sanity and correctness checks */
1942         if (!ns->lines.ce) {
1943                 NS_ERR("write_byte: chip is disabled, ignore write\n");
1944                 return;
1945         }
1946         if (ns->lines.ale && ns->lines.cle) {
1947                 NS_ERR("write_byte: ALE and CLE pins are high simultaneously, ignore write\n");
1948                 return;
1949         }
1950
1951         if (ns->lines.cle == 1) {
1952                 /*
1953                  * The byte written is a command.
1954                  */
1955
1956                 if (byte == NAND_CMD_RESET) {
1957                         NS_LOG("reset chip\n");
1958                         switch_to_ready_state(ns, NS_STATUS_OK(ns));
1959                         return;
1960                 }
1961
1962                 /* Check that the command byte is correct */
1963                 if (check_command(byte)) {
1964                         NS_ERR("write_byte: unknown command %#x\n", (uint)byte);
1965                         return;
1966                 }
1967
1968                 if (NS_STATE(ns->state) == STATE_DATAOUT_STATUS
1969                         || NS_STATE(ns->state) == STATE_DATAOUT) {
1970                         int row = ns->regs.row;
1971
1972                         switch_state(ns);
1973                         if (byte == NAND_CMD_RNDOUT)
1974                                 ns->regs.row = row;
1975                 }
1976
1977                 /* Check if chip is expecting command */
1978                 if (NS_STATE(ns->nxstate) != STATE_UNKNOWN && !(ns->nxstate & STATE_CMD_MASK)) {
1979                         /* Do not warn if only 2 id bytes are read */
1980                         if (!(ns->regs.command == NAND_CMD_READID &&
1981                             NS_STATE(ns->state) == STATE_DATAOUT_ID && ns->regs.count == 2)) {
1982                                 /*
1983                                  * We are in situation when something else (not command)
1984                                  * was expected but command was input. In this case ignore
1985                                  * previous command(s)/state(s) and accept the last one.
1986                                  */
1987                                 NS_WARN("write_byte: command (%#x) wasn't expected, expected state is %s, "
1988                                         "ignore previous states\n", (uint)byte, get_state_name(ns->nxstate));
1989                         }
1990                         switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1991                 }
1992
1993                 NS_DBG("command byte corresponding to %s state accepted\n",
1994                         get_state_name(get_state_by_command(byte)));
1995                 ns->regs.command = byte;
1996                 switch_state(ns);
1997
1998         } else if (ns->lines.ale == 1) {
1999                 /*
2000                  * The byte written is an address.
2001                  */
2002
2003                 if (NS_STATE(ns->nxstate) == STATE_UNKNOWN) {
2004
2005                         NS_DBG("write_byte: operation isn't known yet, identify it\n");
2006
2007                         if (find_operation(ns, 1) < 0)
2008                                 return;
2009
2010                         if ((ns->state & ACTION_MASK) && do_state_action(ns, ns->state) < 0) {
2011                                 switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2012                                 return;
2013                         }
2014
2015                         ns->regs.count = 0;
2016                         switch (NS_STATE(ns->nxstate)) {
2017                                 case STATE_ADDR_PAGE:
2018                                         ns->regs.num = ns->geom.pgaddrbytes;
2019                                         break;
2020                                 case STATE_ADDR_SEC:
2021                                         ns->regs.num = ns->geom.secaddrbytes;
2022                                         break;
2023                                 case STATE_ADDR_ZERO:
2024                                         ns->regs.num = 1;
2025                                         break;
2026                                 default:
2027                                         BUG();
2028                         }
2029                 }
2030
2031                 /* Check that chip is expecting address */
2032                 if (!(ns->nxstate & STATE_ADDR_MASK)) {
2033                         NS_ERR("write_byte: address (%#x) isn't expected, expected state is %s, "
2034                                 "switch to STATE_READY\n", (uint)byte, get_state_name(ns->nxstate));
2035                         switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2036                         return;
2037                 }
2038
2039                 /* Check if this is expected byte */
2040                 if (ns->regs.count == ns->regs.num) {
2041                         NS_ERR("write_byte: no more address bytes expected\n");
2042                         switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2043                         return;
2044                 }
2045
2046                 accept_addr_byte(ns, byte);
2047
2048                 ns->regs.count += 1;
2049
2050                 NS_DBG("write_byte: address byte %#x was accepted (%d bytes input, %d expected)\n",
2051                                 (uint)byte, ns->regs.count, ns->regs.num);
2052
2053                 if (ns->regs.count == ns->regs.num) {
2054                         NS_DBG("address (%#x, %#x) is accepted\n", ns->regs.row, ns->regs.column);
2055                         switch_state(ns);
2056                 }
2057
2058         } else {
2059                 /*
2060                  * The byte written is an input data.
2061                  */
2062
2063                 /* Check that chip is expecting data input */
2064                 if (!(ns->state & STATE_DATAIN_MASK)) {
2065                         NS_ERR("write_byte: data input (%#x) isn't expected, state is %s, "
2066                                 "switch to %s\n", (uint)byte,
2067                                 get_state_name(ns->state), get_state_name(STATE_READY));
2068                         switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2069                         return;
2070                 }
2071
2072                 /* Check if this is expected byte */
2073                 if (ns->regs.count == ns->regs.num) {
2074                         NS_WARN("write_byte: %u input bytes has already been accepted, ignore write\n",
2075                                         ns->regs.num);
2076                         return;
2077                 }
2078
2079                 if (ns->busw == 8) {
2080                         ns->buf.byte[ns->regs.count] = byte;
2081                         ns->regs.count += 1;
2082                 } else {
2083                         ns->buf.word[ns->regs.count >> 1] = cpu_to_le16((uint16_t)byte);
2084                         ns->regs.count += 2;
2085                 }
2086         }
2087
2088         return;
2089 }
2090
2091 static void ns_hwcontrol(struct mtd_info *mtd, int cmd, unsigned int bitmask)
2092 {
2093         struct nand_chip *chip = mtd_to_nand(mtd);
2094         struct nandsim *ns = nand_get_controller_data(chip);
2095
2096         ns->lines.cle = bitmask & NAND_CLE ? 1 : 0;
2097         ns->lines.ale = bitmask & NAND_ALE ? 1 : 0;
2098         ns->lines.ce = bitmask & NAND_NCE ? 1 : 0;
2099
2100         if (cmd != NAND_CMD_NONE)
2101                 ns_nand_write_byte(mtd, cmd);
2102 }
2103
2104 static int ns_device_ready(struct mtd_info *mtd)
2105 {
2106         NS_DBG("device_ready\n");
2107         return 1;
2108 }
2109
2110 static uint16_t ns_nand_read_word(struct mtd_info *mtd)
2111 {
2112         struct nand_chip *chip = mtd_to_nand(mtd);
2113
2114         NS_DBG("read_word\n");
2115
2116         return chip->read_byte(mtd) | (chip->read_byte(mtd) << 8);
2117 }
2118
2119 static void ns_nand_write_buf(struct mtd_info *mtd, const u_char *buf, int len)
2120 {
2121         struct nand_chip *chip = mtd_to_nand(mtd);
2122         struct nandsim *ns = nand_get_controller_data(chip);
2123
2124         /* Check that chip is expecting data input */
2125         if (!(ns->state & STATE_DATAIN_MASK)) {
2126                 NS_ERR("write_buf: data input isn't expected, state is %s, "
2127                         "switch to STATE_READY\n", get_state_name(ns->state));
2128                 switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2129                 return;
2130         }
2131
2132         /* Check if these are expected bytes */
2133         if (ns->regs.count + len > ns->regs.num) {
2134                 NS_ERR("write_buf: too many input bytes\n");
2135                 switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2136                 return;
2137         }
2138
2139         memcpy(ns->buf.byte + ns->regs.count, buf, len);
2140         ns->regs.count += len;
2141
2142         if (ns->regs.count == ns->regs.num) {
2143                 NS_DBG("write_buf: %d bytes were written\n", ns->regs.count);
2144         }
2145 }
2146
2147 static void ns_nand_read_buf(struct mtd_info *mtd, u_char *buf, int len)
2148 {
2149         struct nand_chip *chip = mtd_to_nand(mtd);
2150         struct nandsim *ns = nand_get_controller_data(chip);
2151
2152         /* Sanity and correctness checks */
2153         if (!ns->lines.ce) {
2154                 NS_ERR("read_buf: chip is disabled\n");
2155                 return;
2156         }
2157         if (ns->lines.ale || ns->lines.cle) {
2158                 NS_ERR("read_buf: ALE or CLE pin is high\n");
2159                 return;
2160         }
2161         if (!(ns->state & STATE_DATAOUT_MASK)) {
2162                 NS_WARN("read_buf: unexpected data output cycle, current state is %s\n",
2163                         get_state_name(ns->state));
2164                 return;
2165         }
2166
2167         if (NS_STATE(ns->state) != STATE_DATAOUT) {
2168                 int i;
2169
2170                 for (i = 0; i < len; i++)
2171                         buf[i] = mtd_to_nand(mtd)->read_byte(mtd);
2172
2173                 return;
2174         }
2175
2176         /* Check if these are expected bytes */
2177         if (ns->regs.count + len > ns->regs.num) {
2178                 NS_ERR("read_buf: too many bytes to read\n");
2179                 switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2180                 return;
2181         }
2182
2183         memcpy(buf, ns->buf.byte + ns->regs.count, len);
2184         ns->regs.count += len;
2185
2186         if (ns->regs.count == ns->regs.num) {
2187                 if (NS_STATE(ns->nxstate) == STATE_READY)
2188                         switch_state(ns);
2189         }
2190
2191         return;
2192 }
2193
2194 /*
2195  * Module initialization function
2196  */
2197 static int __init ns_init_module(void)
2198 {
2199         struct nand_chip *chip;
2200         struct nandsim *nand;
2201         int retval = -ENOMEM, i;
2202
2203         if (bus_width != 8 && bus_width != 16) {
2204                 NS_ERR("wrong bus width (%d), use only 8 or 16\n", bus_width);
2205                 return -EINVAL;
2206         }
2207
2208         /* Allocate and initialize mtd_info, nand_chip and nandsim structures */
2209         chip = kzalloc(sizeof(struct nand_chip) + sizeof(struct nandsim),
2210                        GFP_KERNEL);
2211         if (!chip) {
2212                 NS_ERR("unable to allocate core structures.\n");
2213                 return -ENOMEM;
2214         }
2215         nsmtd       = nand_to_mtd(chip);
2216         nand        = (struct nandsim *)(chip + 1);
2217         nand_set_controller_data(chip, (void *)nand);
2218
2219         /*
2220          * Register simulator's callbacks.
2221          */
2222         chip->cmd_ctrl   = ns_hwcontrol;
2223         chip->read_byte  = ns_nand_read_byte;
2224         chip->dev_ready  = ns_device_ready;
2225         chip->write_buf  = ns_nand_write_buf;
2226         chip->read_buf   = ns_nand_read_buf;
2227         chip->read_word  = ns_nand_read_word;
2228         chip->ecc.mode   = NAND_ECC_SOFT;
2229         chip->ecc.algo   = NAND_ECC_HAMMING;
2230         /* The NAND_SKIP_BBTSCAN option is necessary for 'overridesize' */
2231         /* and 'badblocks' parameters to work */
2232         chip->options   |= NAND_SKIP_BBTSCAN;
2233
2234         switch (bbt) {
2235         case 2:
2236                  chip->bbt_options |= NAND_BBT_NO_OOB;
2237         case 1:
2238                  chip->bbt_options |= NAND_BBT_USE_FLASH;
2239         case 0:
2240                 break;
2241         default:
2242                 NS_ERR("bbt has to be 0..2\n");
2243                 retval = -EINVAL;
2244                 goto error;
2245         }
2246         /*
2247          * Perform minimum nandsim structure initialization to handle
2248          * the initial ID read command correctly
2249          */
2250         if (id_bytes[6] != 0xFF || id_bytes[7] != 0xFF)
2251                 nand->geom.idbytes = 8;
2252         else if (id_bytes[4] != 0xFF || id_bytes[5] != 0xFF)
2253                 nand->geom.idbytes = 6;
2254         else if (id_bytes[2] != 0xFF || id_bytes[3] != 0xFF)
2255                 nand->geom.idbytes = 4;
2256         else
2257                 nand->geom.idbytes = 2;
2258         nand->regs.status = NS_STATUS_OK(nand);
2259         nand->nxstate = STATE_UNKNOWN;
2260         nand->options |= OPT_PAGE512; /* temporary value */
2261         memcpy(nand->ids, id_bytes, sizeof(nand->ids));
2262         if (bus_width == 16) {
2263                 nand->busw = 16;
2264                 chip->options |= NAND_BUSWIDTH_16;
2265         }
2266
2267         nsmtd->owner = THIS_MODULE;
2268
2269         if ((retval = parse_weakblocks()) != 0)
2270                 goto error;
2271
2272         if ((retval = parse_weakpages()) != 0)
2273                 goto error;
2274
2275         if ((retval = parse_gravepages()) != 0)
2276                 goto error;
2277
2278         retval = nand_scan_ident(nsmtd, 1, NULL);
2279         if (retval) {
2280                 NS_ERR("cannot scan NAND Simulator device\n");
2281                 goto error;
2282         }
2283
2284         if (bch) {
2285                 unsigned int eccsteps, eccbytes;
2286                 if (!mtd_nand_has_bch()) {
2287                         NS_ERR("BCH ECC support is disabled\n");
2288                         retval = -EINVAL;
2289                         goto error;
2290                 }
2291                 /* use 512-byte ecc blocks */
2292                 eccsteps = nsmtd->writesize/512;
2293                 eccbytes = (bch*13+7)/8;
2294                 /* do not bother supporting small page devices */
2295                 if ((nsmtd->oobsize < 64) || !eccsteps) {
2296                         NS_ERR("bch not available on small page devices\n");
2297                         retval = -EINVAL;
2298                         goto error;
2299                 }
2300                 if ((eccbytes*eccsteps+2) > nsmtd->oobsize) {
2301                         NS_ERR("invalid bch value %u\n", bch);
2302                         retval = -EINVAL;
2303                         goto error;
2304                 }
2305                 chip->ecc.mode = NAND_ECC_SOFT;
2306                 chip->ecc.algo = NAND_ECC_BCH;
2307                 chip->ecc.size = 512;
2308                 chip->ecc.strength = bch;
2309                 chip->ecc.bytes = eccbytes;
2310                 NS_INFO("using %u-bit/%u bytes BCH ECC\n", bch, chip->ecc.size);
2311         }
2312
2313         retval = nand_scan_tail(nsmtd);
2314         if (retval) {
2315                 NS_ERR("can't register NAND Simulator\n");
2316                 goto error;
2317         }
2318
2319         if (overridesize) {
2320                 uint64_t new_size = (uint64_t)nsmtd->erasesize << overridesize;
2321                 if (new_size >> overridesize != nsmtd->erasesize) {
2322                         NS_ERR("overridesize is too big\n");
2323                         retval = -EINVAL;
2324                         goto err_exit;
2325                 }
2326                 /* N.B. This relies on nand_scan not doing anything with the size before we change it */
2327                 nsmtd->size = new_size;
2328                 chip->chipsize = new_size;
2329                 chip->chip_shift = ffs(nsmtd->erasesize) + overridesize - 1;
2330                 chip->pagemask = (chip->chipsize >> chip->page_shift) - 1;
2331         }
2332
2333         if ((retval = setup_wear_reporting(nsmtd)) != 0)
2334                 goto err_exit;
2335
2336         if ((retval = init_nandsim(nsmtd)) != 0)
2337                 goto err_exit;
2338
2339         if ((retval = chip->scan_bbt(nsmtd)) != 0)
2340                 goto err_exit;
2341
2342         if ((retval = parse_badblocks(nand, nsmtd)) != 0)
2343                 goto err_exit;
2344
2345         /* Register NAND partitions */
2346         retval = mtd_device_register(nsmtd, &nand->partitions[0],
2347                                      nand->nbparts);
2348         if (retval != 0)
2349                 goto err_exit;
2350
2351         if ((retval = nandsim_debugfs_create(nand)) != 0)
2352                 goto err_exit;
2353
2354         return 0;
2355
2356 err_exit:
2357         free_nandsim(nand);
2358         nand_release(nsmtd);
2359         for (i = 0;i < ARRAY_SIZE(nand->partitions); ++i)
2360                 kfree(nand->partitions[i].name);
2361 error:
2362         kfree(chip);
2363         free_lists();
2364
2365         return retval;
2366 }
2367
2368 module_init(ns_init_module);
2369
2370 /*
2371  * Module clean-up function
2372  */
2373 static void __exit ns_cleanup_module(void)
2374 {
2375         struct nand_chip *chip = mtd_to_nand(nsmtd);
2376         struct nandsim *ns = nand_get_controller_data(chip);
2377         int i;
2378
2379         free_nandsim(ns);    /* Free nandsim private resources */
2380         nand_release(nsmtd); /* Unregister driver */
2381         for (i = 0;i < ARRAY_SIZE(ns->partitions); ++i)
2382                 kfree(ns->partitions[i].name);
2383         kfree(mtd_to_nand(nsmtd));        /* Free other structures */
2384         free_lists();
2385 }
2386
2387 module_exit(ns_cleanup_module);
2388
2389 MODULE_LICENSE ("GPL");
2390 MODULE_AUTHOR ("Artem B. Bityuckiy");
2391 MODULE_DESCRIPTION ("The NAND flash simulator");