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 =
 569                         vzalloc(array_size(sizeof(unsigned long),
 570                                            BITS_TO_LONGS(ns->geom.pgnum)));
 571                 if (!ns->pages_written) {
 572                         NS_ERR("alloc_device: unable to allocate pages written array\n");
 573                         err = -ENOMEM;
 574                         goto err_close;
 575                 }
 576                 ns->file_buf = kmalloc(ns->geom.pgszoob, GFP_KERNEL);
 577                 if (!ns->file_buf) {
 578                         NS_ERR("alloc_device: unable to allocate file buf\n");
 579                         err = -ENOMEM;
 580                         goto err_free;
 581                 }
 582                 ns->cfile = cfile;
 583                 return 0;
 584         }
 585
 586         ns->pages = vmalloc(array_size(sizeof(union ns_mem), ns->geom.pgnum));
 587         if (!ns->pages) {
 588                 NS_ERR("alloc_device: unable to allocate page array\n");
 589                 return -ENOMEM;
 590         }
 591         for (i = 0; i < ns->geom.pgnum; i++) {
 592                 ns->pages[i].byte = NULL;
 593         }
 594         ns->nand_pages_slab = kmem_cache_create("nandsim",
 595                                                 ns->geom.pgszoob, 0, 0, NULL);
 596         if (!ns->nand_pages_slab) {
 597                 NS_ERR("cache_create: unable to create kmem_cache\n");
 598                 return -ENOMEM;
 599         }
 600
 601         return 0;
 602
 603 err_free:
 604         vfree(ns->pages_written);
 605 err_close:
 606         filp_close(cfile, NULL);
 607         return err;
 608 }
 609
 610 /*
 611  * Free any allocated pages, and free the array of page pointers.
 612  */
 613 static void free_device(struct nandsim *ns)
 614 {
 615         int i;
 616
 617         if (ns->cfile) {
 618                 kfree(ns->file_buf);
 619                 vfree(ns->pages_written);
 620                 filp_close(ns->cfile, NULL);
 621                 return;
 622         }
 623
 624         if (ns->pages) {
 625                 for (i = 0; i < ns->geom.pgnum; i++) {
 626                         if (ns->pages[i].byte)
 627                                 kmem_cache_free(ns->nand_pages_slab,
 628                                                 ns->pages[i].byte);
 629                 }
 630                 kmem_cache_destroy(ns->nand_pages_slab);
 631                 vfree(ns->pages);
 632         }
 633 }
 634
 635 static char __init *get_partition_name(int i)
 636 {
 637         return kasprintf(GFP_KERNEL, "NAND simulator partition %d", i);
 638 }
 639
 640 /*
 641  * Initialize the nandsim structure.
 642  *
 643  * RETURNS: 0 if success, -ERRNO if failure.
 644  */
 645 static int __init init_nandsim(struct mtd_info *mtd)
 646 {
 647         struct nand_chip *chip = mtd_to_nand(mtd);
 648         struct nandsim   *ns   = nand_get_controller_data(chip);
 649         int i, ret = 0;
 650         uint64_t remains;
 651         uint64_t next_offset;
 652
 653         if (NS_IS_INITIALIZED(ns)) {
 654                 NS_ERR("init_nandsim: nandsim is already initialized\n");
 655                 return -EIO;
 656         }
 657
 658         /* Force mtd to not do delays */
 659         chip->chip_delay = 0;
 660
 661         /* Initialize the NAND flash parameters */
 662         ns->busw = chip->options & NAND_BUSWIDTH_16 ? 16 : 8;
 663         ns->geom.totsz    = mtd->size;
 664         ns->geom.pgsz     = mtd->writesize;
 665         ns->geom.oobsz    = mtd->oobsize;
 666         ns->geom.secsz    = mtd->erasesize;
 667         ns->geom.pgszoob  = ns->geom.pgsz + ns->geom.oobsz;
 668         ns->geom.pgnum    = div_u64(ns->geom.totsz, ns->geom.pgsz);
 669         ns->geom.totszoob = ns->geom.totsz + (uint64_t)ns->geom.pgnum * ns->geom.oobsz;
 670         ns->geom.secshift = ffs(ns->geom.secsz) - 1;
 671         ns->geom.pgshift  = chip->page_shift;
 672         ns->geom.pgsec    = ns->geom.secsz / ns->geom.pgsz;
 673         ns->geom.secszoob = ns->geom.secsz + ns->geom.oobsz * ns->geom.pgsec;
 674         ns->options = 0;
 675
 676         if (ns->geom.pgsz == 512) {
 677                 ns->options |= OPT_PAGE512;
 678                 if (ns->busw == 8)
 679                         ns->options |= OPT_PAGE512_8BIT;
 680         } else if (ns->geom.pgsz == 2048) {
 681                 ns->options |= OPT_PAGE2048;
 682         } else if (ns->geom.pgsz == 4096) {
 683                 ns->options |= OPT_PAGE4096;
 684         } else {
 685                 NS_ERR("init_nandsim: unknown page size %u\n", ns->geom.pgsz);
 686                 return -EIO;
 687         }
 688
 689         if (ns->options & OPT_SMALLPAGE) {
 690                 if (ns->geom.totsz <= (32 << 20)) {
 691                         ns->geom.pgaddrbytes  = 3;
 692                         ns->geom.secaddrbytes = 2;
 693                 } else {
 694                         ns->geom.pgaddrbytes  = 4;
 695                         ns->geom.secaddrbytes = 3;
 696                 }
 697         } else {
 698                 if (ns->geom.totsz <= (128 << 20)) {
 699                         ns->geom.pgaddrbytes  = 4;
 700                         ns->geom.secaddrbytes = 2;
 701                 } else {
 702                         ns->geom.pgaddrbytes  = 5;
 703                         ns->geom.secaddrbytes = 3;
 704                 }
 705         }
 706
 707         /* Fill the partition_info structure */
 708         if (parts_num > ARRAY_SIZE(ns->partitions)) {
 709                 NS_ERR("too many partitions.\n");
 710                 return -EINVAL;
 711         }
 712         remains = ns->geom.totsz;
 713         next_offset = 0;
 714         for (i = 0; i < parts_num; ++i) {
 715                 uint64_t part_sz = (uint64_t)parts[i] * ns->geom.secsz;
 716
 717                 if (!part_sz || part_sz > remains) {
 718                         NS_ERR("bad partition size.\n");
 719                         return -EINVAL;
 720                 }
 721                 ns->partitions[i].name   = get_partition_name(i);
 722                 if (!ns->partitions[i].name) {
 723                         NS_ERR("unable to allocate memory.\n");
 724                         return -ENOMEM;
 725                 }
 726                 ns->partitions[i].offset = next_offset;
 727                 ns->partitions[i].size   = part_sz;
 728                 next_offset += ns->partitions[i].size;
 729                 remains -= ns->partitions[i].size;
 730         }
 731         ns->nbparts = parts_num;
 732         if (remains) {
 733                 if (parts_num + 1 > ARRAY_SIZE(ns->partitions)) {
 734                         NS_ERR("too many partitions.\n");
 735                         return -EINVAL;
 736                 }
 737                 ns->partitions[i].name   = get_partition_name(i);
 738                 if (!ns->partitions[i].name) {
 739                         NS_ERR("unable to allocate memory.\n");
 740                         return -ENOMEM;
 741                 }
 742                 ns->partitions[i].offset = next_offset;
 743                 ns->partitions[i].size   = remains;
 744                 ns->nbparts += 1;
 745         }
 746
 747         if (ns->busw == 16)
 748                 NS_WARN("16-bit flashes support wasn't tested\n");
 749
 750         printk("flash size: %llu MiB\n",
 751                         (unsigned long long)ns->geom.totsz >> 20);
 752         printk("page size: %u bytes\n",         ns->geom.pgsz);
 753         printk("OOB area size: %u bytes\n",     ns->geom.oobsz);
 754         printk("sector size: %u KiB\n",         ns->geom.secsz >> 10);
 755         printk("pages number: %u\n",            ns->geom.pgnum);
 756         printk("pages per sector: %u\n",        ns->geom.pgsec);
 757         printk("bus width: %u\n",               ns->busw);
 758         printk("bits in sector size: %u\n",     ns->geom.secshift);
 759         printk("bits in page size: %u\n",       ns->geom.pgshift);
 760         printk("bits in OOB size: %u\n",        ffs(ns->geom.oobsz) - 1);
 761         printk("flash size with OOB: %llu KiB\n",
 762                         (unsigned long long)ns->geom.totszoob >> 10);
 763         printk("page address bytes: %u\n",      ns->geom.pgaddrbytes);
 764         printk("sector address bytes: %u\n",    ns->geom.secaddrbytes);
 765         printk("options: %#x\n",                ns->options);
 766
 767         if ((ret = alloc_device(ns)) != 0)
 768                 return ret;
 769
 770         /* Allocate / initialize the internal buffer */
 771         ns->buf.byte = kmalloc(ns->geom.pgszoob, GFP_KERNEL);
 772         if (!ns->buf.byte) {
 773                 NS_ERR("init_nandsim: unable to allocate %u bytes for the internal buffer\n",
 774                         ns->geom.pgszoob);
 775                 return -ENOMEM;
 776         }
 777         memset(ns->buf.byte, 0xFF, ns->geom.pgszoob);
 778
 779         return 0;
 780 }
 781
 782 /*
 783  * Free the nandsim structure.
 784  */
 785 static void free_nandsim(struct nandsim *ns)
 786 {
 787         kfree(ns->buf.byte);
 788         free_device(ns);
 789
 790         return;
 791 }
 792
 793 static int parse_badblocks(struct nandsim *ns, struct mtd_info *mtd)
 794 {
 795         char *w;
 796         int zero_ok;
 797         unsigned int erase_block_no;
 798         loff_t offset;
 799
 800         if (!badblocks)
 801                 return 0;
 802         w = badblocks;
 803         do {
 804                 zero_ok = (*w == '0' ? 1 : 0);
 805                 erase_block_no = simple_strtoul(w, &w, 0);
 806                 if (!zero_ok && !erase_block_no) {
 807                         NS_ERR("invalid badblocks.\n");
 808                         return -EINVAL;
 809                 }
 810                 offset = (loff_t)erase_block_no * ns->geom.secsz;
 811                 if (mtd_block_markbad(mtd, offset)) {
 812                         NS_ERR("invalid badblocks.\n");
 813                         return -EINVAL;
 814                 }
 815                 if (*w == ',')
 816                         w += 1;
 817         } while (*w);
 818         return 0;
 819 }
 820
 821 static int parse_weakblocks(void)
 822 {
 823         char *w;
 824         int zero_ok;
 825         unsigned int erase_block_no;
 826         unsigned int max_erases;
 827         struct weak_block *wb;
 828
 829         if (!weakblocks)
 830                 return 0;
 831         w = weakblocks;
 832         do {
 833                 zero_ok = (*w == '0' ? 1 : 0);
 834                 erase_block_no = simple_strtoul(w, &w, 0);
 835                 if (!zero_ok && !erase_block_no) {
 836                         NS_ERR("invalid weakblocks.\n");
 837                         return -EINVAL;
 838                 }
 839                 max_erases = 3;
 840                 if (*w == ':') {
 841                         w += 1;
 842                         max_erases = simple_strtoul(w, &w, 0);
 843                 }
 844                 if (*w == ',')
 845                         w += 1;
 846                 wb = kzalloc(sizeof(*wb), GFP_KERNEL);
 847                 if (!wb) {
 848                         NS_ERR("unable to allocate memory.\n");
 849                         return -ENOMEM;
 850                 }
 851                 wb->erase_block_no = erase_block_no;
 852                 wb->max_erases = max_erases;
 853                 list_add(&wb->list, &weak_blocks);
 854         } while (*w);
 855         return 0;
 856 }
 857
 858 static int erase_error(unsigned int erase_block_no)
 859 {
 860         struct weak_block *wb;
 861
 862         list_for_each_entry(wb, &weak_blocks, list)
 863                 if (wb->erase_block_no == erase_block_no) {
 864                         if (wb->erases_done >= wb->max_erases)
 865                                 return 1;
 866                         wb->erases_done += 1;
 867                         return 0;
 868                 }
 869         return 0;
 870 }
 871
 872 static int parse_weakpages(void)
 873 {
 874         char *w;
 875         int zero_ok;
 876         unsigned int page_no;
 877         unsigned int max_writes;
 878         struct weak_page *wp;
 879
 880         if (!weakpages)
 881                 return 0;
 882         w = weakpages;
 883         do {
 884                 zero_ok = (*w == '0' ? 1 : 0);
 885                 page_no = simple_strtoul(w, &w, 0);
 886                 if (!zero_ok && !page_no) {
 887                         NS_ERR("invalid weakpages.\n");
 888                         return -EINVAL;
 889                 }
 890                 max_writes = 3;
 891                 if (*w == ':') {
 892                         w += 1;
 893                         max_writes = simple_strtoul(w, &w, 0);
 894                 }
 895                 if (*w == ',')
 896                         w += 1;
 897                 wp = kzalloc(sizeof(*wp), GFP_KERNEL);
 898                 if (!wp) {
 899                         NS_ERR("unable to allocate memory.\n");
 900                         return -ENOMEM;
 901                 }
 902                 wp->page_no = page_no;
 903                 wp->max_writes = max_writes;
 904                 list_add(&wp->list, &weak_pages);
 905         } while (*w);
 906         return 0;
 907 }
 908
 909 static int write_error(unsigned int page_no)
 910 {
 911         struct weak_page *wp;
 912
 913         list_for_each_entry(wp, &weak_pages, list)
 914                 if (wp->page_no == page_no) {
 915                         if (wp->writes_done >= wp->max_writes)
 916                                 return 1;
 917                         wp->writes_done += 1;
 918                         return 0;
 919                 }
 920         return 0;
 921 }
 922
 923 static int parse_gravepages(void)
 924 {
 925         char *g;
 926         int zero_ok;
 927         unsigned int page_no;
 928         unsigned int max_reads;
 929         struct grave_page *gp;
 930
 931         if (!gravepages)
 932                 return 0;
 933         g = gravepages;
 934         do {
 935                 zero_ok = (*g == '0' ? 1 : 0);
 936                 page_no = simple_strtoul(g, &g, 0);
 937                 if (!zero_ok && !page_no) {
 938                         NS_ERR("invalid gravepagess.\n");
 939                         return -EINVAL;
 940                 }
 941                 max_reads = 3;
 942                 if (*g == ':') {
 943                         g += 1;
 944                         max_reads = simple_strtoul(g, &g, 0);
 945                 }
 946                 if (*g == ',')
 947                         g += 1;
 948                 gp = kzalloc(sizeof(*gp), GFP_KERNEL);
 949                 if (!gp) {
 950                         NS_ERR("unable to allocate memory.\n");
 951                         return -ENOMEM;
 952                 }
 953                 gp->page_no = page_no;
 954                 gp->max_reads = max_reads;
 955                 list_add(&gp->list, &grave_pages);
 956         } while (*g);
 957         return 0;
 958 }
 959
 960 static int read_error(unsigned int page_no)
 961 {
 962         struct grave_page *gp;
 963
 964         list_for_each_entry(gp, &grave_pages, list)
 965                 if (gp->page_no == page_no) {
 966                         if (gp->reads_done >= gp->max_reads)
 967                                 return 1;
 968                         gp->reads_done += 1;
 969                         return 0;
 970                 }
 971         return 0;
 972 }
 973
 974 static void free_lists(void)
 975 {
 976         struct list_head *pos, *n;
 977         list_for_each_safe(pos, n, &weak_blocks) {
 978                 list_del(pos);
 979                 kfree(list_entry(pos, struct weak_block, list));
 980         }
 981         list_for_each_safe(pos, n, &weak_pages) {
 982                 list_del(pos);
 983                 kfree(list_entry(pos, struct weak_page, list));
 984         }
 985         list_for_each_safe(pos, n, &grave_pages) {
 986                 list_del(pos);
 987                 kfree(list_entry(pos, struct grave_page, list));
 988         }
 989         kfree(erase_block_wear);
 990 }
 991
 992 static int setup_wear_reporting(struct mtd_info *mtd)
 993 {
 994         size_t mem;
 995
 996         wear_eb_count = div_u64(mtd->size, mtd->erasesize);
 997         mem = wear_eb_count * sizeof(unsigned long);
 998         if (mem / sizeof(unsigned long) != wear_eb_count) {
 999                 NS_ERR("Too many erase blocks for wear reporting\n");
1000                 return -ENOMEM;
1001         }
1002         erase_block_wear = kzalloc(mem, GFP_KERNEL);
1003         if (!erase_block_wear) {
1004                 NS_ERR("Too many erase blocks for wear reporting\n");
1005                 return -ENOMEM;
1006         }
1007         return 0;
1008 }
1009
1010 static void update_wear(unsigned int erase_block_no)
1011 {
1012         if (!erase_block_wear)
1013                 return;
1014         total_wear += 1;
1015         /*
1016          * TODO: Notify this through a debugfs entry,
1017          * instead of showing an error message.
1018          */
1019         if (total_wear == 0)
1020                 NS_ERR("Erase counter total overflow\n");
1021         erase_block_wear[erase_block_no] += 1;
1022         if (erase_block_wear[erase_block_no] == 0)
1023                 NS_ERR("Erase counter overflow for erase block %u\n", erase_block_no);
1024 }
1025
1026 /*
1027  * Returns the string representation of 'state' state.
1028  */
1029 static char *get_state_name(uint32_t state)
1030 {
1031         switch (NS_STATE(state)) {
1032                 case STATE_CMD_READ0:
1033                         return "STATE_CMD_READ0";
1034                 case STATE_CMD_READ1:
1035                         return "STATE_CMD_READ1";
1036                 case STATE_CMD_PAGEPROG:
1037                         return "STATE_CMD_PAGEPROG";
1038                 case STATE_CMD_READOOB:
1039                         return "STATE_CMD_READOOB";
1040                 case STATE_CMD_READSTART:
1041                         return "STATE_CMD_READSTART";
1042                 case STATE_CMD_ERASE1:
1043                         return "STATE_CMD_ERASE1";
1044                 case STATE_CMD_STATUS:
1045                         return "STATE_CMD_STATUS";
1046                 case STATE_CMD_SEQIN:
1047                         return "STATE_CMD_SEQIN";
1048                 case STATE_CMD_READID:
1049                         return "STATE_CMD_READID";
1050                 case STATE_CMD_ERASE2:
1051                         return "STATE_CMD_ERASE2";
1052                 case STATE_CMD_RESET:
1053                         return "STATE_CMD_RESET";
1054                 case STATE_CMD_RNDOUT:
1055                         return "STATE_CMD_RNDOUT";
1056                 case STATE_CMD_RNDOUTSTART:
1057                         return "STATE_CMD_RNDOUTSTART";
1058                 case STATE_ADDR_PAGE:
1059                         return "STATE_ADDR_PAGE";
1060                 case STATE_ADDR_SEC:
1061                         return "STATE_ADDR_SEC";
1062                 case STATE_ADDR_ZERO:
1063                         return "STATE_ADDR_ZERO";
1064                 case STATE_ADDR_COLUMN:
1065                         return "STATE_ADDR_COLUMN";
1066                 case STATE_DATAIN:
1067                         return "STATE_DATAIN";
1068                 case STATE_DATAOUT:
1069                         return "STATE_DATAOUT";
1070                 case STATE_DATAOUT_ID:
1071                         return "STATE_DATAOUT_ID";
1072                 case STATE_DATAOUT_STATUS:
1073                         return "STATE_DATAOUT_STATUS";
1074                 case STATE_READY:
1075                         return "STATE_READY";
1076                 case STATE_UNKNOWN:
1077                         return "STATE_UNKNOWN";
1078         }
1079
1080         NS_ERR("get_state_name: unknown state, BUG\n");
1081         return NULL;
1082 }
1083
1084 /*
1085  * Check if command is valid.
1086  *
1087  * RETURNS: 1 if wrong command, 0 if right.
1088  */
1089 static int check_command(int cmd)
1090 {
1091         switch (cmd) {
1092
1093         case NAND_CMD_READ0:
1094         case NAND_CMD_READ1:
1095         case NAND_CMD_READSTART:
1096         case NAND_CMD_PAGEPROG:
1097         case NAND_CMD_READOOB:
1098         case NAND_CMD_ERASE1:
1099         case NAND_CMD_STATUS:
1100         case NAND_CMD_SEQIN:
1101         case NAND_CMD_READID:
1102         case NAND_CMD_ERASE2:
1103         case NAND_CMD_RESET:
1104         case NAND_CMD_RNDOUT:
1105         case NAND_CMD_RNDOUTSTART:
1106                 return 0;
1107
1108         default:
1109                 return 1;
1110         }
1111 }
1112
1113 /*
1114  * Returns state after command is accepted by command number.
1115  */
1116 static uint32_t get_state_by_command(unsigned command)
1117 {
1118         switch (command) {
1119                 case NAND_CMD_READ0:
1120                         return STATE_CMD_READ0;
1121                 case NAND_CMD_READ1:
1122                         return STATE_CMD_READ1;
1123                 case NAND_CMD_PAGEPROG:
1124                         return STATE_CMD_PAGEPROG;
1125                 case NAND_CMD_READSTART:
1126                         return STATE_CMD_READSTART;
1127                 case NAND_CMD_READOOB:
1128                         return STATE_CMD_READOOB;
1129                 case NAND_CMD_ERASE1:
1130                         return STATE_CMD_ERASE1;
1131                 case NAND_CMD_STATUS:
1132                         return STATE_CMD_STATUS;
1133                 case NAND_CMD_SEQIN:
1134                         return STATE_CMD_SEQIN;
1135                 case NAND_CMD_READID:
1136                         return STATE_CMD_READID;
1137                 case NAND_CMD_ERASE2:
1138                         return STATE_CMD_ERASE2;
1139                 case NAND_CMD_RESET:
1140                         return STATE_CMD_RESET;
1141                 case NAND_CMD_RNDOUT:
1142                         return STATE_CMD_RNDOUT;
1143                 case NAND_CMD_RNDOUTSTART:
1144                         return STATE_CMD_RNDOUTSTART;
1145         }
1146
1147         NS_ERR("get_state_by_command: unknown command, BUG\n");
1148         return 0;
1149 }
1150
1151 /*
1152  * Move an address byte to the correspondent internal register.
1153  */
1154 static inline void accept_addr_byte(struct nandsim *ns, u_char bt)
1155 {
1156         uint byte = (uint)bt;
1157
1158         if (ns->regs.count < (ns->geom.pgaddrbytes - ns->geom.secaddrbytes))
1159                 ns->regs.column |= (byte << 8 * ns->regs.count);
1160         else {
1161                 ns->regs.row |= (byte << 8 * (ns->regs.count -
1162                                                 ns->geom.pgaddrbytes +
1163                                                 ns->geom.secaddrbytes));
1164         }
1165
1166         return;
1167 }
1168
1169 /*
1170  * Switch to STATE_READY state.
1171  */
1172 static inline void switch_to_ready_state(struct nandsim *ns, u_char status)
1173 {
1174         NS_DBG("switch_to_ready_state: switch to %s state\n", get_state_name(STATE_READY));
1175
1176         ns->state       = STATE_READY;
1177         ns->nxstate     = STATE_UNKNOWN;
1178         ns->op          = NULL;
1179         ns->npstates    = 0;
1180         ns->stateidx    = 0;
1181         ns->regs.num    = 0;
1182         ns->regs.count  = 0;
1183         ns->regs.off    = 0;
1184         ns->regs.row    = 0;
1185         ns->regs.column = 0;
1186         ns->regs.status = status;
1187 }
1188
1189 /*
1190  * If the operation isn't known yet, try to find it in the global array
1191  * of supported operations.
1192  *
1193  * Operation can be unknown because of the following.
1194  *   1. New command was accepted and this is the first call to find the
1195  *      correspondent states chain. In this case ns->npstates = 0;
1196  *   2. There are several operations which begin with the same command(s)
1197  *      (for example program from the second half and read from the
1198  *      second half operations both begin with the READ1 command). In this
1199  *      case the ns->pstates[] array contains previous states.
1200  *
1201  * Thus, the function tries to find operation containing the following
1202  * states (if the 'flag' parameter is 0):
1203  *    ns->pstates[0], ... ns->pstates[ns->npstates], ns->state
1204  *
1205  * If (one and only one) matching operation is found, it is accepted (
1206  * ns->ops, ns->state, ns->nxstate are initialized, ns->npstate is
1207  * zeroed).
1208  *
1209  * If there are several matches, the current state is pushed to the
1210  * ns->pstates.
1211  *
1212  * The operation can be unknown only while commands are input to the chip.
1213  * As soon as address command is accepted, the operation must be known.
1214  * In such situation the function is called with 'flag' != 0, and the
1215  * operation is searched using the following pattern:
1216  *     ns->pstates[0], ... ns->pstates[ns->npstates], <address input>
1217  *
1218  * It is supposed that this pattern must either match one operation or
1219  * none. There can't be ambiguity in that case.
1220  *
1221  * If no matches found, the function does the following:
1222  *   1. if there are saved states present, try to ignore them and search
1223  *      again only using the last command. If nothing was found, switch
1224  *      to the STATE_READY state.
1225  *   2. if there are no saved states, switch to the STATE_READY state.
1226  *
1227  * RETURNS: -2 - no matched operations found.
1228  *          -1 - several matches.
1229  *           0 - operation is found.
1230  */
1231 static int find_operation(struct nandsim *ns, uint32_t flag)
1232 {
1233         int opsfound = 0;
1234         int i, j, idx = 0;
1235
1236         for (i = 0; i < NS_OPER_NUM; i++) {
1237
1238                 int found = 1;
1239
1240                 if (!(ns->options & ops[i].reqopts))
1241                         /* Ignore operations we can't perform */
1242                         continue;
1243
1244                 if (flag) {
1245                         if (!(ops[i].states[ns->npstates] & STATE_ADDR_MASK))
1246                                 continue;
1247                 } else {
1248                         if (NS_STATE(ns->state) != NS_STATE(ops[i].states[ns->npstates]))
1249                                 continue;
1250                 }
1251
1252                 for (j = 0; j < ns->npstates; j++)
1253                         if (NS_STATE(ops[i].states[j]) != NS_STATE(ns->pstates[j])
1254                                 && (ns->options & ops[idx].reqopts)) {
1255                                 found = 0;
1256                                 break;
1257                         }
1258
1259                 if (found) {
1260                         idx = i;
1261                         opsfound += 1;
1262                 }
1263         }
1264
1265         if (opsfound == 1) {
1266                 /* Exact match */
1267                 ns->op = &ops[idx].states[0];
1268                 if (flag) {
1269                         /*
1270                          * In this case the find_operation function was
1271                          * called when address has just began input. But it isn't
1272                          * yet fully input and the current state must
1273                          * not be one of STATE_ADDR_*, but the STATE_ADDR_*
1274                          * state must be the next state (ns->nxstate).
1275                          */
1276                         ns->stateidx = ns->npstates - 1;
1277                 } else {
1278                         ns->stateidx = ns->npstates;
1279                 }
1280                 ns->npstates = 0;
1281                 ns->state = ns->op[ns->stateidx];
1282                 ns->nxstate = ns->op[ns->stateidx + 1];
1283                 NS_DBG("find_operation: operation found, index: %d, state: %s, nxstate %s\n",
1284                                 idx, get_state_name(ns->state), get_state_name(ns->nxstate));
1285                 return 0;
1286         }
1287
1288         if (opsfound == 0) {
1289                 /* Nothing was found. Try to ignore previous commands (if any) and search again */
1290                 if (ns->npstates != 0) {
1291                         NS_DBG("find_operation: no operation found, try again with state %s\n",
1292                                         get_state_name(ns->state));
1293                         ns->npstates = 0;
1294                         return find_operation(ns, 0);
1295
1296                 }
1297                 NS_DBG("find_operation: no operations found\n");
1298                 switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1299                 return -2;
1300         }
1301
1302         if (flag) {
1303                 /* This shouldn't happen */
1304                 NS_DBG("find_operation: BUG, operation must be known if address is input\n");
1305                 return -2;
1306         }
1307
1308         NS_DBG("find_operation: there is still ambiguity\n");
1309
1310         ns->pstates[ns->npstates++] = ns->state;
1311
1312         return -1;
1313 }
1314
1315 static void put_pages(struct nandsim *ns)
1316 {
1317         int i;
1318
1319         for (i = 0; i < ns->held_cnt; i++)
1320                 put_page(ns->held_pages[i]);
1321 }
1322
1323 /* Get page cache pages in advance to provide NOFS memory allocation */
1324 static int get_pages(struct nandsim *ns, struct file *file, size_t count, loff_t pos)
1325 {
1326         pgoff_t index, start_index, end_index;
1327         struct page *page;
1328         struct address_space *mapping = file->f_mapping;
1329
1330         start_index = pos >> PAGE_SHIFT;
1331         end_index = (pos + count - 1) >> PAGE_SHIFT;
1332         if (end_index - start_index + 1 > NS_MAX_HELD_PAGES)
1333                 return -EINVAL;
1334         ns->held_cnt = 0;
1335         for (index = start_index; index <= end_index; index++) {
1336                 page = find_get_page(mapping, index);
1337                 if (page == NULL) {
1338                         page = find_or_create_page(mapping, index, GFP_NOFS);
1339                         if (page == NULL) {
1340                                 write_inode_now(mapping->host, 1);
1341                                 page = find_or_create_page(mapping, index, GFP_NOFS);
1342                         }
1343                         if (page == NULL) {
1344                                 put_pages(ns);
1345                                 return -ENOMEM;
1346                         }
1347                         unlock_page(page);
1348                 }
1349                 ns->held_pages[ns->held_cnt++] = page;
1350         }
1351         return 0;
1352 }
1353
1354 static ssize_t read_file(struct nandsim *ns, struct file *file, void *buf, size_t count, loff_t pos)
1355 {
1356         ssize_t tx;
1357         int err;
1358         unsigned int noreclaim_flag;
1359
1360         err = get_pages(ns, file, count, pos);
1361         if (err)
1362                 return err;
1363         noreclaim_flag = memalloc_noreclaim_save();
1364         tx = kernel_read(file, buf, count, &pos);
1365         memalloc_noreclaim_restore(noreclaim_flag);
1366         put_pages(ns);
1367         return tx;
1368 }
1369
1370 static ssize_t write_file(struct nandsim *ns, struct file *file, void *buf, size_t count, loff_t pos)
1371 {
1372         ssize_t tx;
1373         int err;
1374         unsigned int noreclaim_flag;
1375
1376         err = get_pages(ns, file, count, pos);
1377         if (err)
1378                 return err;
1379         noreclaim_flag = memalloc_noreclaim_save();
1380         tx = kernel_write(file, buf, count, &pos);
1381         memalloc_noreclaim_restore(noreclaim_flag);
1382         put_pages(ns);
1383         return tx;
1384 }
1385
1386 /*
1387  * Returns a pointer to the current page.
1388  */
1389 static inline union ns_mem *NS_GET_PAGE(struct nandsim *ns)
1390 {
1391         return &(ns->pages[ns->regs.row]);
1392 }
1393
1394 /*
1395  * Retuns a pointer to the current byte, within the current page.
1396  */
1397 static inline u_char *NS_PAGE_BYTE_OFF(struct nandsim *ns)
1398 {
1399         return NS_GET_PAGE(ns)->byte + ns->regs.column + ns->regs.off;
1400 }
1401
1402 static int do_read_error(struct nandsim *ns, int num)
1403 {
1404         unsigned int page_no = ns->regs.row;
1405
1406         if (read_error(page_no)) {
1407                 prandom_bytes(ns->buf.byte, num);
1408                 NS_WARN("simulating read error in page %u\n", page_no);
1409                 return 1;
1410         }
1411         return 0;
1412 }
1413
1414 static void do_bit_flips(struct nandsim *ns, int num)
1415 {
1416         if (bitflips && prandom_u32() < (1 << 22)) {
1417                 int flips = 1;
1418                 if (bitflips > 1)
1419                         flips = (prandom_u32() % (int) bitflips) + 1;
1420                 while (flips--) {
1421                         int pos = prandom_u32() % (num * 8);
1422                         ns->buf.byte[pos / 8] ^= (1 << (pos % 8));
1423                         NS_WARN("read_page: flipping bit %d in page %d "
1424                                 "reading from %d ecc: corrected=%u failed=%u\n",
1425                                 pos, ns->regs.row, ns->regs.column + ns->regs.off,
1426                                 nsmtd->ecc_stats.corrected, nsmtd->ecc_stats.failed);
1427                 }
1428         }
1429 }
1430
1431 /*
1432  * Fill the NAND buffer with data read from the specified page.
1433  */
1434 static void read_page(struct nandsim *ns, int num)
1435 {
1436         union ns_mem *mypage;
1437
1438         if (ns->cfile) {
1439                 if (!test_bit(ns->regs.row, ns->pages_written)) {
1440                         NS_DBG("read_page: page %d not written\n", ns->regs.row);
1441                         memset(ns->buf.byte, 0xFF, num);
1442                 } else {
1443                         loff_t pos;
1444                         ssize_t tx;
1445
1446                         NS_DBG("read_page: page %d written, reading from %d\n",
1447                                 ns->regs.row, ns->regs.column + ns->regs.off);
1448                         if (do_read_error(ns, num))
1449                                 return;
1450                         pos = (loff_t)NS_RAW_OFFSET(ns) + ns->regs.off;
1451                         tx = read_file(ns, ns->cfile, ns->buf.byte, num, pos);
1452                         if (tx != num) {
1453                                 NS_ERR("read_page: read error for page %d ret %ld\n", ns->regs.row, (long)tx);
1454                                 return;
1455                         }
1456                         do_bit_flips(ns, num);
1457                 }
1458                 return;
1459         }
1460
1461         mypage = NS_GET_PAGE(ns);
1462         if (mypage->byte == NULL) {
1463                 NS_DBG("read_page: page %d not allocated\n", ns->regs.row);
1464                 memset(ns->buf.byte, 0xFF, num);
1465         } else {
1466                 NS_DBG("read_page: page %d allocated, reading from %d\n",
1467                         ns->regs.row, ns->regs.column + ns->regs.off);
1468                 if (do_read_error(ns, num))
1469                         return;
1470                 memcpy(ns->buf.byte, NS_PAGE_BYTE_OFF(ns), num);
1471                 do_bit_flips(ns, num);
1472         }
1473 }
1474
1475 /*
1476  * Erase all pages in the specified sector.
1477  */
1478 static void erase_sector(struct nandsim *ns)
1479 {
1480         union ns_mem *mypage;
1481         int i;
1482
1483         if (ns->cfile) {
1484                 for (i = 0; i < ns->geom.pgsec; i++)
1485                         if (__test_and_clear_bit(ns->regs.row + i,
1486                                                  ns->pages_written)) {
1487                                 NS_DBG("erase_sector: freeing page %d\n", ns->regs.row + i);
1488                         }
1489                 return;
1490         }
1491
1492         mypage = NS_GET_PAGE(ns);
1493         for (i = 0; i < ns->geom.pgsec; i++) {
1494                 if (mypage->byte != NULL) {
1495                         NS_DBG("erase_sector: freeing page %d\n", ns->regs.row+i);
1496                         kmem_cache_free(ns->nand_pages_slab, mypage->byte);
1497                         mypage->byte = NULL;
1498                 }
1499                 mypage++;
1500         }
1501 }
1502
1503 /*
1504  * Program the specified page with the contents from the NAND buffer.
1505  */
1506 static int prog_page(struct nandsim *ns, int num)
1507 {
1508         int i;
1509         union ns_mem *mypage;
1510         u_char *pg_off;
1511
1512         if (ns->cfile) {
1513                 loff_t off;
1514                 ssize_t tx;
1515                 int all;
1516
1517                 NS_DBG("prog_page: writing page %d\n", ns->regs.row);
1518                 pg_off = ns->file_buf + ns->regs.column + ns->regs.off;
1519                 off = (loff_t)NS_RAW_OFFSET(ns) + ns->regs.off;
1520                 if (!test_bit(ns->regs.row, ns->pages_written)) {
1521                         all = 1;
1522                         memset(ns->file_buf, 0xff, ns->geom.pgszoob);
1523                 } else {
1524                         all = 0;
1525                         tx = read_file(ns, ns->cfile, pg_off, num, off);
1526                         if (tx != num) {
1527                                 NS_ERR("prog_page: read error for page %d ret %ld\n", ns->regs.row, (long)tx);
1528                                 return -1;
1529                         }
1530                 }
1531                 for (i = 0; i < num; i++)
1532                         pg_off[i] &= ns->buf.byte[i];
1533                 if (all) {
1534                         loff_t pos = (loff_t)ns->regs.row * ns->geom.pgszoob;
1535                         tx = write_file(ns, ns->cfile, ns->file_buf, ns->geom.pgszoob, pos);
1536                         if (tx != ns->geom.pgszoob) {
1537                                 NS_ERR("prog_page: write error for page %d ret %ld\n", ns->regs.row, (long)tx);
1538                                 return -1;
1539                         }
1540                         __set_bit(ns->regs.row, ns->pages_written);
1541                 } else {
1542                         tx = write_file(ns, ns->cfile, pg_off, num, off);
1543                         if (tx != num) {
1544                                 NS_ERR("prog_page: write error for page %d ret %ld\n", ns->regs.row, (long)tx);
1545                                 return -1;
1546                         }
1547                 }
1548                 return 0;
1549         }
1550
1551         mypage = NS_GET_PAGE(ns);
1552         if (mypage->byte == NULL) {
1553                 NS_DBG("prog_page: allocating page %d\n", ns->regs.row);
1554                 /*
1555                  * We allocate memory with GFP_NOFS because a flash FS may
1556                  * utilize this. If it is holding an FS lock, then gets here,
1557                  * then kernel memory alloc runs writeback which goes to the FS
1558                  * again and deadlocks. This was seen in practice.
1559                  */
1560                 mypage->byte = kmem_cache_alloc(ns->nand_pages_slab, GFP_NOFS);
1561                 if (mypage->byte == NULL) {
1562                         NS_ERR("prog_page: error allocating memory for page %d\n", ns->regs.row);
1563                         return -1;
1564                 }
1565                 memset(mypage->byte, 0xFF, ns->geom.pgszoob);
1566         }
1567
1568         pg_off = NS_PAGE_BYTE_OFF(ns);
1569         for (i = 0; i < num; i++)
1570                 pg_off[i] &= ns->buf.byte[i];
1571
1572         return 0;
1573 }
1574
1575 /*
1576  * If state has any action bit, perform this action.
1577  *
1578  * RETURNS: 0 if success, -1 if error.
1579  */
1580 static int do_state_action(struct nandsim *ns, uint32_t action)
1581 {
1582         int num;
1583         int busdiv = ns->busw == 8 ? 1 : 2;
1584         unsigned int erase_block_no, page_no;
1585
1586         action &= ACTION_MASK;
1587
1588         /* Check that page address input is correct */
1589         if (action != ACTION_SECERASE && ns->regs.row >= ns->geom.pgnum) {
1590                 NS_WARN("do_state_action: wrong page number (%#x)\n", ns->regs.row);
1591                 return -1;
1592         }
1593
1594         switch (action) {
1595
1596         case ACTION_CPY:
1597                 /*
1598                  * Copy page data to the internal buffer.
1599                  */
1600
1601                 /* Column shouldn't be very large */
1602                 if (ns->regs.column >= (ns->geom.pgszoob - ns->regs.off)) {
1603                         NS_ERR("do_state_action: column number is too large\n");
1604                         break;
1605                 }
1606                 num = ns->geom.pgszoob - ns->regs.off - ns->regs.column;
1607                 read_page(ns, num);
1608
1609                 NS_DBG("do_state_action: (ACTION_CPY:) copy %d bytes to int buf, raw offset %d\n",
1610                         num, NS_RAW_OFFSET(ns) + ns->regs.off);
1611
1612                 if (ns->regs.off == 0)
1613                         NS_LOG("read page %d\n", ns->regs.row);
1614                 else if (ns->regs.off < ns->geom.pgsz)
1615                         NS_LOG("read page %d (second half)\n", ns->regs.row);
1616                 else
1617                         NS_LOG("read OOB of page %d\n", ns->regs.row);
1618
1619                 NS_UDELAY(access_delay);
1620                 NS_UDELAY(input_cycle * ns->geom.pgsz / 1000 / busdiv);
1621
1622                 break;
1623
1624         case ACTION_SECERASE:
1625                 /*
1626                  * Erase sector.
1627                  */
1628
1629                 if (ns->lines.wp) {
1630                         NS_ERR("do_state_action: device is write-protected, ignore sector erase\n");
1631                         return -1;
1632                 }
1633
1634                 if (ns->regs.row >= ns->geom.pgnum - ns->geom.pgsec
1635                         || (ns->regs.row & ~(ns->geom.secsz - 1))) {
1636                         NS_ERR("do_state_action: wrong sector address (%#x)\n", ns->regs.row);
1637                         return -1;
1638                 }
1639
1640                 ns->regs.row = (ns->regs.row <<
1641                                 8 * (ns->geom.pgaddrbytes - ns->geom.secaddrbytes)) | ns->regs.column;
1642                 ns->regs.column = 0;
1643
1644                 erase_block_no = ns->regs.row >> (ns->geom.secshift - ns->geom.pgshift);
1645
1646                 NS_DBG("do_state_action: erase sector at address %#x, off = %d\n",
1647                                 ns->regs.row, NS_RAW_OFFSET(ns));
1648                 NS_LOG("erase sector %u\n", erase_block_no);
1649
1650                 erase_sector(ns);
1651
1652                 NS_MDELAY(erase_delay);
1653
1654                 if (erase_block_wear)
1655                         update_wear(erase_block_no);
1656
1657                 if (erase_error(erase_block_no)) {
1658                         NS_WARN("simulating erase failure in erase block %u\n", erase_block_no);
1659                         return -1;
1660                 }
1661
1662                 break;
1663
1664         case ACTION_PRGPAGE:
1665                 /*
1666                  * Program page - move internal buffer data to the page.
1667                  */
1668
1669                 if (ns->lines.wp) {
1670                         NS_WARN("do_state_action: device is write-protected, programm\n");
1671                         return -1;
1672                 }
1673
1674                 num = ns->geom.pgszoob - ns->regs.off - ns->regs.column;
1675                 if (num != ns->regs.count) {
1676                         NS_ERR("do_state_action: too few bytes were input (%d instead of %d)\n",
1677                                         ns->regs.count, num);
1678                         return -1;
1679                 }
1680
1681                 if (prog_page(ns, num) == -1)
1682                         return -1;
1683
1684                 page_no = ns->regs.row;
1685
1686                 NS_DBG("do_state_action: copy %d bytes from int buf to (%#x, %#x), raw off = %d\n",
1687                         num, ns->regs.row, ns->regs.column, NS_RAW_OFFSET(ns) + ns->regs.off);
1688                 NS_LOG("programm page %d\n", ns->regs.row);
1689
1690                 NS_UDELAY(programm_delay);
1691                 NS_UDELAY(output_cycle * ns->geom.pgsz / 1000 / busdiv);
1692
1693                 if (write_error(page_no)) {
1694                         NS_WARN("simulating write failure in page %u\n", page_no);
1695                         return -1;
1696                 }
1697
1698                 break;
1699
1700         case ACTION_ZEROOFF:
1701                 NS_DBG("do_state_action: set internal offset to 0\n");
1702                 ns->regs.off = 0;
1703                 break;
1704
1705         case ACTION_HALFOFF:
1706                 if (!(ns->options & OPT_PAGE512_8BIT)) {
1707                         NS_ERR("do_state_action: BUG! can't skip half of page for non-512"
1708                                 "byte page size 8x chips\n");
1709                         return -1;
1710                 }
1711                 NS_DBG("do_state_action: set internal offset to %d\n", ns->geom.pgsz/2);
1712                 ns->regs.off = ns->geom.pgsz/2;
1713                 break;
1714
1715         case ACTION_OOBOFF:
1716                 NS_DBG("do_state_action: set internal offset to %d\n", ns->geom.pgsz);
1717                 ns->regs.off = ns->geom.pgsz;
1718                 break;
1719
1720         default:
1721                 NS_DBG("do_state_action: BUG! unknown action\n");
1722         }
1723
1724         return 0;
1725 }
1726
1727 /*
1728  * Switch simulator's state.
1729  */
1730 static void switch_state(struct nandsim *ns)
1731 {
1732         if (ns->op) {
1733                 /*
1734                  * The current operation have already been identified.
1735                  * Just follow the states chain.
1736                  */
1737
1738                 ns->stateidx += 1;
1739                 ns->state = ns->nxstate;
1740                 ns->nxstate = ns->op[ns->stateidx + 1];
1741
1742                 NS_DBG("switch_state: operation is known, switch to the next state, "
1743                         "state: %s, nxstate: %s\n",
1744                         get_state_name(ns->state), get_state_name(ns->nxstate));
1745
1746                 /* See, whether we need to do some action */
1747                 if ((ns->state & ACTION_MASK) && do_state_action(ns, ns->state) < 0) {
1748                         switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1749                         return;
1750                 }
1751
1752         } else {
1753                 /*
1754                  * We don't yet know which operation we perform.
1755                  * Try to identify it.
1756                  */
1757
1758                 /*
1759                  *  The only event causing the switch_state function to
1760                  *  be called with yet unknown operation is new command.
1761                  */
1762                 ns->state = get_state_by_command(ns->regs.command);
1763
1764                 NS_DBG("switch_state: operation is unknown, try to find it\n");
1765
1766                 if (find_operation(ns, 0) != 0)
1767                         return;
1768
1769                 if ((ns->state & ACTION_MASK) && do_state_action(ns, ns->state) < 0) {
1770                         switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1771                         return;
1772                 }
1773         }
1774
1775         /* For 16x devices column means the page offset in words */
1776         if ((ns->nxstate & STATE_ADDR_MASK) && ns->busw == 16) {
1777                 NS_DBG("switch_state: double the column number for 16x device\n");
1778                 ns->regs.column <<= 1;
1779         }
1780
1781         if (NS_STATE(ns->nxstate) == STATE_READY) {
1782                 /*
1783                  * The current state is the last. Return to STATE_READY
1784                  */
1785
1786                 u_char status = NS_STATUS_OK(ns);
1787
1788                 /* In case of data states, see if all bytes were input/output */
1789                 if ((ns->state & (STATE_DATAIN_MASK | STATE_DATAOUT_MASK))
1790                         && ns->regs.count != ns->regs.num) {
1791                         NS_WARN("switch_state: not all bytes were processed, %d left\n",
1792                                         ns->regs.num - ns->regs.count);
1793                         status = NS_STATUS_FAILED(ns);
1794                 }
1795
1796                 NS_DBG("switch_state: operation complete, switch to STATE_READY state\n");
1797
1798                 switch_to_ready_state(ns, status);
1799
1800                 return;
1801         } else if (ns->nxstate & (STATE_DATAIN_MASK | STATE_DATAOUT_MASK)) {
1802                 /*
1803                  * If the next state is data input/output, switch to it now
1804                  */
1805
1806                 ns->state      = ns->nxstate;
1807                 ns->nxstate    = ns->op[++ns->stateidx + 1];
1808                 ns->regs.num   = ns->regs.count = 0;
1809
1810                 NS_DBG("switch_state: the next state is data I/O, switch, "
1811                         "state: %s, nxstate: %s\n",
1812                         get_state_name(ns->state), get_state_name(ns->nxstate));
1813
1814                 /*
1815                  * Set the internal register to the count of bytes which
1816                  * are expected to be input or output
1817                  */
1818                 switch (NS_STATE(ns->state)) {
1819                         case STATE_DATAIN:
1820                         case STATE_DATAOUT:
1821                                 ns->regs.num = ns->geom.pgszoob - ns->regs.off - ns->regs.column;
1822                                 break;
1823
1824                         case STATE_DATAOUT_ID:
1825                                 ns->regs.num = ns->geom.idbytes;
1826                                 break;
1827
1828                         case STATE_DATAOUT_STATUS:
1829                                 ns->regs.count = ns->regs.num = 0;
1830                                 break;
1831
1832                         default:
1833                                 NS_ERR("switch_state: BUG! unknown data state\n");
1834                 }
1835
1836         } else if (ns->nxstate & STATE_ADDR_MASK) {
1837                 /*
1838                  * If the next state is address input, set the internal
1839                  * register to the number of expected address bytes
1840                  */
1841
1842                 ns->regs.count = 0;
1843
1844                 switch (NS_STATE(ns->nxstate)) {
1845                         case STATE_ADDR_PAGE:
1846                                 ns->regs.num = ns->geom.pgaddrbytes;
1847
1848                                 break;
1849                         case STATE_ADDR_SEC:
1850                                 ns->regs.num = ns->geom.secaddrbytes;
1851                                 break;
1852
1853                         case STATE_ADDR_ZERO:
1854                                 ns->regs.num = 1;
1855                                 break;
1856
1857                         case STATE_ADDR_COLUMN:
1858                                 /* Column address is always 2 bytes */
1859                                 ns->regs.num = ns->geom.pgaddrbytes - ns->geom.secaddrbytes;
1860                                 break;
1861
1862                         default:
1863                                 NS_ERR("switch_state: BUG! unknown address state\n");
1864                 }
1865         } else {
1866                 /*
1867                  * Just reset internal counters.
1868                  */
1869
1870                 ns->regs.num = 0;
1871                 ns->regs.count = 0;
1872         }
1873 }
1874
1875 static u_char ns_nand_read_byte(struct mtd_info *mtd)
1876 {
1877         struct nand_chip *chip = mtd_to_nand(mtd);
1878         struct nandsim *ns = nand_get_controller_data(chip);
1879         u_char outb = 0x00;
1880
1881         /* Sanity and correctness checks */
1882         if (!ns->lines.ce) {
1883                 NS_ERR("read_byte: chip is disabled, return %#x\n", (uint)outb);
1884                 return outb;
1885         }
1886         if (ns->lines.ale || ns->lines.cle) {
1887                 NS_ERR("read_byte: ALE or CLE pin is high, return %#x\n", (uint)outb);
1888                 return outb;
1889         }
1890         if (!(ns->state & STATE_DATAOUT_MASK)) {
1891                 NS_WARN("read_byte: unexpected data output cycle, state is %s "
1892                         "return %#x\n", get_state_name(ns->state), (uint)outb);
1893                 return outb;
1894         }
1895
1896         /* Status register may be read as many times as it is wanted */
1897         if (NS_STATE(ns->state) == STATE_DATAOUT_STATUS) {
1898                 NS_DBG("read_byte: return %#x status\n", ns->regs.status);
1899                 return ns->regs.status;
1900         }
1901
1902         /* Check if there is any data in the internal buffer which may be read */
1903         if (ns->regs.count == ns->regs.num) {
1904                 NS_WARN("read_byte: no more data to output, return %#x\n", (uint)outb);
1905                 return outb;
1906         }
1907
1908         switch (NS_STATE(ns->state)) {
1909                 case STATE_DATAOUT:
1910                         if (ns->busw == 8) {
1911                                 outb = ns->buf.byte[ns->regs.count];
1912                                 ns->regs.count += 1;
1913                         } else {
1914                                 outb = (u_char)cpu_to_le16(ns->buf.word[ns->regs.count >> 1]);
1915                                 ns->regs.count += 2;
1916                         }
1917                         break;
1918                 case STATE_DATAOUT_ID:
1919                         NS_DBG("read_byte: read ID byte %d, total = %d\n", ns->regs.count, ns->regs.num);
1920                         outb = ns->ids[ns->regs.count];
1921                         ns->regs.count += 1;
1922                         break;
1923                 default:
1924                         BUG();
1925         }
1926
1927         if (ns->regs.count == ns->regs.num) {
1928                 NS_DBG("read_byte: all bytes were read\n");
1929
1930                 if (NS_STATE(ns->nxstate) == STATE_READY)
1931                         switch_state(ns);
1932         }
1933
1934         return outb;
1935 }
1936
1937 static void ns_nand_write_byte(struct mtd_info *mtd, u_char byte)
1938 {
1939         struct nand_chip *chip = mtd_to_nand(mtd);
1940         struct nandsim *ns = nand_get_controller_data(chip);
1941
1942         /* Sanity and correctness checks */
1943         if (!ns->lines.ce) {
1944                 NS_ERR("write_byte: chip is disabled, ignore write\n");
1945                 return;
1946         }
1947         if (ns->lines.ale && ns->lines.cle) {
1948                 NS_ERR("write_byte: ALE and CLE pins are high simultaneously, ignore write\n");
1949                 return;
1950         }
1951
1952         if (ns->lines.cle == 1) {
1953                 /*
1954                  * The byte written is a command.
1955                  */
1956
1957                 if (byte == NAND_CMD_RESET) {
1958                         NS_LOG("reset chip\n");
1959                         switch_to_ready_state(ns, NS_STATUS_OK(ns));
1960                         return;
1961                 }
1962
1963                 /* Check that the command byte is correct */
1964                 if (check_command(byte)) {
1965                         NS_ERR("write_byte: unknown command %#x\n", (uint)byte);
1966                         return;
1967                 }
1968
1969                 if (NS_STATE(ns->state) == STATE_DATAOUT_STATUS
1970                         || NS_STATE(ns->state) == STATE_DATAOUT) {
1971                         int row = ns->regs.row;
1972
1973                         switch_state(ns);
1974                         if (byte == NAND_CMD_RNDOUT)
1975                                 ns->regs.row = row;
1976                 }
1977
1978                 /* Check if chip is expecting command */
1979                 if (NS_STATE(ns->nxstate) != STATE_UNKNOWN && !(ns->nxstate & STATE_CMD_MASK)) {
1980                         /* Do not warn if only 2 id bytes are read */
1981                         if (!(ns->regs.command == NAND_CMD_READID &&
1982                             NS_STATE(ns->state) == STATE_DATAOUT_ID && ns->regs.count == 2)) {
1983                                 /*
1984                                  * We are in situation when something else (not command)
1985                                  * was expected but command was input. In this case ignore
1986                                  * previous command(s)/state(s) and accept the last one.
1987                                  */
1988                                 NS_WARN("write_byte: command (%#x) wasn't expected, expected state is %s, "
1989                                         "ignore previous states\n", (uint)byte, get_state_name(ns->nxstate));
1990                         }
1991                         switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1992                 }
1993
1994                 NS_DBG("command byte corresponding to %s state accepted\n",
1995                         get_state_name(get_state_by_command(byte)));
1996                 ns->regs.command = byte;
1997                 switch_state(ns);
1998
1999         } else if (ns->lines.ale == 1) {
2000                 /*
2001                  * The byte written is an address.
2002                  */
2003
2004                 if (NS_STATE(ns->nxstate) == STATE_UNKNOWN) {
2005
2006                         NS_DBG("write_byte: operation isn't known yet, identify it\n");
2007
2008                         if (find_operation(ns, 1) < 0)
2009                                 return;
2010
2011                         if ((ns->state & ACTION_MASK) && do_state_action(ns, ns->state) < 0) {
2012                                 switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2013                                 return;
2014                         }
2015
2016                         ns->regs.count = 0;
2017                         switch (NS_STATE(ns->nxstate)) {
2018                                 case STATE_ADDR_PAGE:
2019                                         ns->regs.num = ns->geom.pgaddrbytes;
2020                                         break;
2021                                 case STATE_ADDR_SEC:
2022                                         ns->regs.num = ns->geom.secaddrbytes;
2023                                         break;
2024                                 case STATE_ADDR_ZERO:
2025                                         ns->regs.num = 1;
2026                                         break;
2027                                 default:
2028                                         BUG();
2029                         }
2030                 }
2031
2032                 /* Check that chip is expecting address */
2033                 if (!(ns->nxstate & STATE_ADDR_MASK)) {
2034                         NS_ERR("write_byte: address (%#x) isn't expected, expected state is %s, "
2035                                 "switch to STATE_READY\n", (uint)byte, get_state_name(ns->nxstate));
2036                         switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2037                         return;
2038                 }
2039
2040                 /* Check if this is expected byte */
2041                 if (ns->regs.count == ns->regs.num) {
2042                         NS_ERR("write_byte: no more address bytes expected\n");
2043                         switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2044                         return;
2045                 }
2046
2047                 accept_addr_byte(ns, byte);
2048
2049                 ns->regs.count += 1;
2050
2051                 NS_DBG("write_byte: address byte %#x was accepted (%d bytes input, %d expected)\n",
2052                                 (uint)byte, ns->regs.count, ns->regs.num);
2053
2054                 if (ns->regs.count == ns->regs.num) {
2055                         NS_DBG("address (%#x, %#x) is accepted\n", ns->regs.row, ns->regs.column);
2056                         switch_state(ns);
2057                 }
2058
2059         } else {
2060                 /*
2061                  * The byte written is an input data.
2062                  */
2063
2064                 /* Check that chip is expecting data input */
2065                 if (!(ns->state & STATE_DATAIN_MASK)) {
2066                         NS_ERR("write_byte: data input (%#x) isn't expected, state is %s, "
2067                                 "switch to %s\n", (uint)byte,
2068                                 get_state_name(ns->state), get_state_name(STATE_READY));
2069                         switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2070                         return;
2071                 }
2072
2073                 /* Check if this is expected byte */
2074                 if (ns->regs.count == ns->regs.num) {
2075                         NS_WARN("write_byte: %u input bytes has already been accepted, ignore write\n",
2076                                         ns->regs.num);
2077                         return;
2078                 }
2079
2080                 if (ns->busw == 8) {
2081                         ns->buf.byte[ns->regs.count] = byte;
2082                         ns->regs.count += 1;
2083                 } else {
2084                         ns->buf.word[ns->regs.count >> 1] = cpu_to_le16((uint16_t)byte);
2085                         ns->regs.count += 2;
2086                 }
2087         }
2088
2089         return;
2090 }
2091
2092 static void ns_hwcontrol(struct mtd_info *mtd, int cmd, unsigned int bitmask)
2093 {
2094         struct nand_chip *chip = mtd_to_nand(mtd);
2095         struct nandsim *ns = nand_get_controller_data(chip);
2096
2097         ns->lines.cle = bitmask & NAND_CLE ? 1 : 0;
2098         ns->lines.ale = bitmask & NAND_ALE ? 1 : 0;
2099         ns->lines.ce = bitmask & NAND_NCE ? 1 : 0;
2100
2101         if (cmd != NAND_CMD_NONE)
2102                 ns_nand_write_byte(mtd, cmd);
2103 }
2104
2105 static int ns_device_ready(struct mtd_info *mtd)
2106 {
2107         NS_DBG("device_ready\n");
2108         return 1;
2109 }
2110
2111 static uint16_t ns_nand_read_word(struct mtd_info *mtd)
2112 {
2113         struct nand_chip *chip = mtd_to_nand(mtd);
2114
2115         NS_DBG("read_word\n");
2116
2117         return chip->read_byte(mtd) | (chip->read_byte(mtd) << 8);
2118 }
2119
2120 static void ns_nand_write_buf(struct mtd_info *mtd, const u_char *buf, int len)
2121 {
2122         struct nand_chip *chip = mtd_to_nand(mtd);
2123         struct nandsim *ns = nand_get_controller_data(chip);
2124
2125         /* Check that chip is expecting data input */
2126         if (!(ns->state & STATE_DATAIN_MASK)) {
2127                 NS_ERR("write_buf: data input isn't expected, state is %s, "
2128                         "switch to STATE_READY\n", get_state_name(ns->state));
2129                 switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2130                 return;
2131         }
2132
2133         /* Check if these are expected bytes */
2134         if (ns->regs.count + len > ns->regs.num) {
2135                 NS_ERR("write_buf: too many input bytes\n");
2136                 switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2137                 return;
2138         }
2139
2140         memcpy(ns->buf.byte + ns->regs.count, buf, len);
2141         ns->regs.count += len;
2142
2143         if (ns->regs.count == ns->regs.num) {
2144                 NS_DBG("write_buf: %d bytes were written\n", ns->regs.count);
2145         }
2146 }
2147
2148 static void ns_nand_read_buf(struct mtd_info *mtd, u_char *buf, int len)
2149 {
2150         struct nand_chip *chip = mtd_to_nand(mtd);
2151         struct nandsim *ns = nand_get_controller_data(chip);
2152
2153         /* Sanity and correctness checks */
2154         if (!ns->lines.ce) {
2155                 NS_ERR("read_buf: chip is disabled\n");
2156                 return;
2157         }
2158         if (ns->lines.ale || ns->lines.cle) {
2159                 NS_ERR("read_buf: ALE or CLE pin is high\n");
2160                 return;
2161         }
2162         if (!(ns->state & STATE_DATAOUT_MASK)) {
2163                 NS_WARN("read_buf: unexpected data output cycle, current state is %s\n",
2164                         get_state_name(ns->state));
2165                 return;
2166         }
2167
2168         if (NS_STATE(ns->state) != STATE_DATAOUT) {
2169                 int i;
2170
2171                 for (i = 0; i < len; i++)
2172                         buf[i] = mtd_to_nand(mtd)->read_byte(mtd);
2173
2174                 return;
2175         }
2176
2177         /* Check if these are expected bytes */
2178         if (ns->regs.count + len > ns->regs.num) {
2179                 NS_ERR("read_buf: too many bytes to read\n");
2180                 switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2181                 return;
2182         }
2183
2184         memcpy(buf, ns->buf.byte + ns->regs.count, len);
2185         ns->regs.count += len;
2186
2187         if (ns->regs.count == ns->regs.num) {
2188                 if (NS_STATE(ns->nxstate) == STATE_READY)
2189                         switch_state(ns);
2190         }
2191
2192         return;
2193 }
2194
2195 static int ns_attach_chip(struct nand_chip *chip)
2196 {
2197         unsigned int eccsteps, eccbytes;
2198
2199         if (!bch)
2200                 return 0;
2201
2202         if (!mtd_nand_has_bch()) {
2203                 NS_ERR("BCH ECC support is disabled\n");
2204                 return -EINVAL;
2205         }
2206
2207         /* Use 512-byte ecc blocks */
2208         eccsteps = nsmtd->writesize / 512;
2209         eccbytes = ((bch * 13) + 7) / 8;
2210
2211         /* Do not bother supporting small page devices */
2212         if (nsmtd->oobsize < 64 || !eccsteps) {
2213                 NS_ERR("BCH not available on small page devices\n");
2214                 return -EINVAL;
2215         }
2216
2217         if (((eccbytes * eccsteps) + 2) > nsmtd->oobsize) {
2218                 NS_ERR("Invalid BCH value %u\n", bch);
2219                 return -EINVAL;
2220         }
2221
2222         chip->ecc.mode = NAND_ECC_SOFT;
2223         chip->ecc.algo = NAND_ECC_BCH;
2224         chip->ecc.size = 512;
2225         chip->ecc.strength = bch;
2226         chip->ecc.bytes = eccbytes;
2227
2228         NS_INFO("Using %u-bit/%u bytes BCH ECC\n", bch, chip->ecc.size);
2229
2230         return 0;
2231 }
2232
2233 static const struct nand_controller_ops ns_controller_ops = {
2234         .attach_chip = ns_attach_chip,
2235 };
2236
2237 /*
2238  * Module initialization function
2239  */
2240 static int __init ns_init_module(void)
2241 {
2242         struct nand_chip *chip;
2243         struct nandsim *nand;
2244         int retval = -ENOMEM, i;
2245
2246         if (bus_width != 8 && bus_width != 16) {
2247                 NS_ERR("wrong bus width (%d), use only 8 or 16\n", bus_width);
2248                 return -EINVAL;
2249         }
2250
2251         /* Allocate and initialize mtd_info, nand_chip and nandsim structures */
2252         chip = kzalloc(sizeof(struct nand_chip) + sizeof(struct nandsim),
2253                        GFP_KERNEL);
2254         if (!chip) {
2255                 NS_ERR("unable to allocate core structures.\n");
2256                 return -ENOMEM;
2257         }
2258         nsmtd       = nand_to_mtd(chip);
2259         nand        = (struct nandsim *)(chip + 1);
2260         nand_set_controller_data(chip, (void *)nand);
2261
2262         /*
2263          * Register simulator's callbacks.
2264          */
2265         chip->cmd_ctrl   = ns_hwcontrol;
2266         chip->read_byte  = ns_nand_read_byte;
2267         chip->dev_ready  = ns_device_ready;
2268         chip->write_buf  = ns_nand_write_buf;
2269         chip->read_buf   = ns_nand_read_buf;
2270         chip->read_word  = ns_nand_read_word;
2271         chip->ecc.mode   = NAND_ECC_SOFT;
2272         chip->ecc.algo   = NAND_ECC_HAMMING;
2273         /* The NAND_SKIP_BBTSCAN option is necessary for 'overridesize' */
2274         /* and 'badblocks' parameters to work */
2275         chip->options   |= NAND_SKIP_BBTSCAN;
2276
2277         switch (bbt) {
2278         case 2:
2279                  chip->bbt_options |= NAND_BBT_NO_OOB;
2280         case 1:
2281                  chip->bbt_options |= NAND_BBT_USE_FLASH;
2282         case 0:
2283                 break;
2284         default:
2285                 NS_ERR("bbt has to be 0..2\n");
2286                 retval = -EINVAL;
2287                 goto error;
2288         }
2289         /*
2290          * Perform minimum nandsim structure initialization to handle
2291          * the initial ID read command correctly
2292          */
2293         if (id_bytes[6] != 0xFF || id_bytes[7] != 0xFF)
2294                 nand->geom.idbytes = 8;
2295         else if (id_bytes[4] != 0xFF || id_bytes[5] != 0xFF)
2296                 nand->geom.idbytes = 6;
2297         else if (id_bytes[2] != 0xFF || id_bytes[3] != 0xFF)
2298                 nand->geom.idbytes = 4;
2299         else
2300                 nand->geom.idbytes = 2;
2301         nand->regs.status = NS_STATUS_OK(nand);
2302         nand->nxstate = STATE_UNKNOWN;
2303         nand->options |= OPT_PAGE512; /* temporary value */
2304         memcpy(nand->ids, id_bytes, sizeof(nand->ids));
2305         if (bus_width == 16) {
2306                 nand->busw = 16;
2307                 chip->options |= NAND_BUSWIDTH_16;
2308         }
2309
2310         nsmtd->owner = THIS_MODULE;
2311
2312         if ((retval = parse_weakblocks()) != 0)
2313                 goto error;
2314
2315         if ((retval = parse_weakpages()) != 0)
2316                 goto error;
2317
2318         if ((retval = parse_gravepages()) != 0)
2319                 goto error;
2320
2321         chip->dummy_controller.ops = &ns_controller_ops;
2322         retval = nand_scan(chip, 1);
2323         if (retval) {
2324                 NS_ERR("Could not scan NAND Simulator device\n");
2325                 goto error;
2326         }
2327
2328         if (overridesize) {
2329                 uint64_t new_size = (uint64_t)nsmtd->erasesize << overridesize;
2330                 if (new_size >> overridesize != nsmtd->erasesize) {
2331                         NS_ERR("overridesize is too big\n");
2332                         retval = -EINVAL;
2333                         goto err_exit;
2334                 }
2335                 /* N.B. This relies on nand_scan not doing anything with the size before we change it */
2336                 nsmtd->size = new_size;
2337                 chip->chipsize = new_size;
2338                 chip->chip_shift = ffs(nsmtd->erasesize) + overridesize - 1;
2339                 chip->pagemask = (chip->chipsize >> chip->page_shift) - 1;
2340         }
2341
2342         if ((retval = setup_wear_reporting(nsmtd)) != 0)
2343                 goto err_exit;
2344
2345         if ((retval = init_nandsim(nsmtd)) != 0)
2346                 goto err_exit;
2347
2348         if ((retval = nand_create_bbt(chip)) != 0)
2349                 goto err_exit;
2350
2351         if ((retval = parse_badblocks(nand, nsmtd)) != 0)
2352                 goto err_exit;
2353
2354         /* Register NAND partitions */
2355         retval = mtd_device_register(nsmtd, &nand->partitions[0],
2356                                      nand->nbparts);
2357         if (retval != 0)
2358                 goto err_exit;
2359
2360         if ((retval = nandsim_debugfs_create(nand)) != 0)
2361                 goto err_exit;
2362
2363         return 0;
2364
2365 err_exit:
2366         free_nandsim(nand);
2367         nand_release(chip);
2368         for (i = 0;i < ARRAY_SIZE(nand->partitions); ++i)
2369                 kfree(nand->partitions[i].name);
2370 error:
2371         kfree(chip);
2372         free_lists();
2373
2374         return retval;
2375 }
2376
2377 module_init(ns_init_module);
2378
2379 /*
2380  * Module clean-up function
2381  */
2382 static void __exit ns_cleanup_module(void)
2383 {
2384         struct nand_chip *chip = mtd_to_nand(nsmtd);
2385         struct nandsim *ns = nand_get_controller_data(chip);
2386         int i;
2387
2388         free_nandsim(ns);    /* Free nandsim private resources */
2389         nand_release(chip); /* Unregister driver */
2390         for (i = 0;i < ARRAY_SIZE(ns->partitions); ++i)
2391                 kfree(ns->partitions[i].name);
2392         kfree(mtd_to_nand(nsmtd));        /* Free other structures */
2393         free_lists();
2394 }
2395
2396 module_exit(ns_cleanup_module);
2397
2398 MODULE_LICENSE ("GPL");
2399 MODULE_AUTHOR ("Artem B. Bityuckiy");
2400 MODULE_DESCRIPTION ("The NAND flash simulator");