drivers/mtd/nand/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 #include <linux/init.h>
  27 #include <linux/types.h>
  28 #include <linux/module.h>
  29 #include <linux/moduleparam.h>
  30 #include <linux/vmalloc.h>
  31 #include <linux/math64.h>
  32 #include <linux/slab.h>
  33 #include <linux/errno.h>
  34 #include <linux/string.h>
  35 #include <linux/mtd/mtd.h>
  36 #include <linux/mtd/nand.h>
  37 #include <linux/mtd/nand_bch.h>
  38 #include <linux/mtd/partitions.h>
  39 #include <linux/delay.h>
  40 #include <linux/list.h>
  41 #include <linux/random.h>
  42 #include <linux/sched.h>
  43 #include <linux/fs.h>
  44 #include <linux/pagemap.h>
  45 #include <linux/seq_file.h>
  46 #include <linux/debugfs.h>
  47
  48 /* Default simulator parameters values */
  49 #if !defined(CONFIG_NANDSIM_FIRST_ID_BYTE)  || \
  50     !defined(CONFIG_NANDSIM_SECOND_ID_BYTE) || \
  51     !defined(CONFIG_NANDSIM_THIRD_ID_BYTE)  || \
  52     !defined(CONFIG_NANDSIM_FOURTH_ID_BYTE)
  53 #define CONFIG_NANDSIM_FIRST_ID_BYTE  0x98
  54 #define CONFIG_NANDSIM_SECOND_ID_BYTE 0x39
  55 #define CONFIG_NANDSIM_THIRD_ID_BYTE  0xFF /* No byte */
  56 #define CONFIG_NANDSIM_FOURTH_ID_BYTE 0xFF /* No byte */
  57 #endif
  58
  59 #ifndef CONFIG_NANDSIM_ACCESS_DELAY
  60 #define CONFIG_NANDSIM_ACCESS_DELAY 25
  61 #endif
  62 #ifndef CONFIG_NANDSIM_PROGRAMM_DELAY
  63 #define CONFIG_NANDSIM_PROGRAMM_DELAY 200
  64 #endif
  65 #ifndef CONFIG_NANDSIM_ERASE_DELAY
  66 #define CONFIG_NANDSIM_ERASE_DELAY 2
  67 #endif
  68 #ifndef CONFIG_NANDSIM_OUTPUT_CYCLE
  69 #define CONFIG_NANDSIM_OUTPUT_CYCLE 40
  70 #endif
  71 #ifndef CONFIG_NANDSIM_INPUT_CYCLE
  72 #define CONFIG_NANDSIM_INPUT_CYCLE  50
  73 #endif
  74 #ifndef CONFIG_NANDSIM_BUS_WIDTH
  75 #define CONFIG_NANDSIM_BUS_WIDTH  8
  76 #endif
  77 #ifndef CONFIG_NANDSIM_DO_DELAYS
  78 #define CONFIG_NANDSIM_DO_DELAYS  0
  79 #endif
  80 #ifndef CONFIG_NANDSIM_LOG
  81 #define CONFIG_NANDSIM_LOG        0
  82 #endif
  83 #ifndef CONFIG_NANDSIM_DBG
  84 #define CONFIG_NANDSIM_DBG        0
  85 #endif
  86 #ifndef CONFIG_NANDSIM_MAX_PARTS
  87 #define CONFIG_NANDSIM_MAX_PARTS  32
  88 #endif
  89
  90 static uint first_id_byte  = CONFIG_NANDSIM_FIRST_ID_BYTE;
  91 static uint second_id_byte = CONFIG_NANDSIM_SECOND_ID_BYTE;
  92 static uint third_id_byte  = CONFIG_NANDSIM_THIRD_ID_BYTE;
  93 static uint fourth_id_byte = CONFIG_NANDSIM_FOURTH_ID_BYTE;
  94 static uint access_delay   = CONFIG_NANDSIM_ACCESS_DELAY;
  95 static uint programm_delay = CONFIG_NANDSIM_PROGRAMM_DELAY;
  96 static uint erase_delay    = CONFIG_NANDSIM_ERASE_DELAY;
  97 static uint output_cycle   = CONFIG_NANDSIM_OUTPUT_CYCLE;
  98 static uint input_cycle    = CONFIG_NANDSIM_INPUT_CYCLE;
  99 static uint bus_width      = CONFIG_NANDSIM_BUS_WIDTH;
 100 static uint do_delays      = CONFIG_NANDSIM_DO_DELAYS;
 101 static uint log            = CONFIG_NANDSIM_LOG;
 102 static uint dbg            = CONFIG_NANDSIM_DBG;
 103 static unsigned long parts[CONFIG_NANDSIM_MAX_PARTS];
 104 static unsigned int parts_num;
 105 static char *badblocks = NULL;
 106 static char *weakblocks = NULL;
 107 static char *weakpages = NULL;
 108 static unsigned int bitflips = 0;
 109 static char *gravepages = NULL;
 110 static unsigned int overridesize = 0;
 111 static char *cache_file = NULL;
 112 static unsigned int bbt;
 113 static unsigned int bch;
 114
 115 module_param(first_id_byte,  uint, 0400);
 116 module_param(second_id_byte, uint, 0400);
 117 module_param(third_id_byte,  uint, 0400);
 118 module_param(fourth_id_byte, uint, 0400);
 119 module_param(access_delay,   uint, 0400);
 120 module_param(programm_delay, uint, 0400);
 121 module_param(erase_delay,    uint, 0400);
 122 module_param(output_cycle,   uint, 0400);
 123 module_param(input_cycle,    uint, 0400);
 124 module_param(bus_width,      uint, 0400);
 125 module_param(do_delays,      uint, 0400);
 126 module_param(log,            uint, 0400);
 127 module_param(dbg,            uint, 0400);
 128 module_param_array(parts, ulong, &parts_num, 0400);
 129 module_param(badblocks,      charp, 0400);
 130 module_param(weakblocks,     charp, 0400);
 131 module_param(weakpages,      charp, 0400);
 132 module_param(bitflips,       uint, 0400);
 133 module_param(gravepages,     charp, 0400);
 134 module_param(overridesize,   uint, 0400);
 135 module_param(cache_file,     charp, 0400);
 136 module_param(bbt,            uint, 0400);
 137 module_param(bch,            uint, 0400);
 138
 139 MODULE_PARM_DESC(first_id_byte,  "The first byte returned by NAND Flash 'read ID' command (manufacturer ID)");
 140 MODULE_PARM_DESC(second_id_byte, "The second byte returned by NAND Flash 'read ID' command (chip ID)");
 141 MODULE_PARM_DESC(third_id_byte,  "The third byte returned by NAND Flash 'read ID' command");
 142 MODULE_PARM_DESC(fourth_id_byte, "The fourth byte returned by NAND Flash 'read ID' command");
 143 MODULE_PARM_DESC(access_delay,   "Initial page access delay (microseconds)");
 144 MODULE_PARM_DESC(programm_delay, "Page programm delay (microseconds");
 145 MODULE_PARM_DESC(erase_delay,    "Sector erase delay (milliseconds)");
 146 MODULE_PARM_DESC(output_cycle,   "Word output (from flash) time (nanoseconds)");
 147 MODULE_PARM_DESC(input_cycle,    "Word input (to flash) time (nanoseconds)");
 148 MODULE_PARM_DESC(bus_width,      "Chip's bus width (8- or 16-bit)");
 149 MODULE_PARM_DESC(do_delays,      "Simulate NAND delays using busy-waits if not zero");
 150 MODULE_PARM_DESC(log,            "Perform logging if not zero");
 151 MODULE_PARM_DESC(dbg,            "Output debug information if not zero");
 152 MODULE_PARM_DESC(parts,          "Partition sizes (in erase blocks) separated by commas");
 153 /* Page and erase block positions for the following parameters are independent of any partitions */
 154 MODULE_PARM_DESC(badblocks,      "Erase blocks that are initially marked bad, separated by commas");
 155 MODULE_PARM_DESC(weakblocks,     "Weak erase blocks [: remaining erase cycles (defaults to 3)]"
 156                                  " separated by commas e.g. 113:2 means eb 113"
 157                                  " can be erased only twice before failing");
 158 MODULE_PARM_DESC(weakpages,      "Weak pages [: maximum writes (defaults to 3)]"
 159                                  " separated by commas e.g. 1401:2 means page 1401"
 160                                  " can be written only twice before failing");
 161 MODULE_PARM_DESC(bitflips,       "Maximum number of random bit flips per page (zero by default)");
 162 MODULE_PARM_DESC(gravepages,     "Pages that lose data [: maximum reads (defaults to 3)]"
 163                                  " separated by commas e.g. 1401:2 means page 1401"
 164                                  " can be read only twice before failing");
 165 MODULE_PARM_DESC(overridesize,   "Specifies the NAND Flash size overriding the ID bytes. "
 166                                  "The size is specified in erase blocks and as the exponent of a power of two"
 167                                  " e.g. 5 means a size of 32 erase blocks");
 168 MODULE_PARM_DESC(cache_file,     "File to use to cache nand pages instead of memory");
 169 MODULE_PARM_DESC(bbt,            "0 OOB, 1 BBT with marker in OOB, 2 BBT with marker in data area");
 170 MODULE_PARM_DESC(bch,            "Enable BCH ecc and set how many bits should "
 171                                  "be correctable in 512-byte blocks");
 172
 173 /* The largest possible page size */
 174 #define NS_LARGEST_PAGE_SIZE    4096
 175
 176 /* The prefix for simulator output */
 177 #define NS_OUTPUT_PREFIX "[nandsim]"
 178
 179 /* Simulator's output macros (logging, debugging, warning, error) */
 180 #define NS_LOG(args...) \
 181         do { if (log) printk(KERN_DEBUG NS_OUTPUT_PREFIX " log: " args); } while(0)
 182 #define NS_DBG(args...) \
 183         do { if (dbg) printk(KERN_DEBUG NS_OUTPUT_PREFIX " debug: " args); } while(0)
 184 #define NS_WARN(args...) \
 185         do { printk(KERN_WARNING NS_OUTPUT_PREFIX " warning: " args); } while(0)
 186 #define NS_ERR(args...) \
 187         do { printk(KERN_ERR NS_OUTPUT_PREFIX " error: " args); } while(0)
 188 #define NS_INFO(args...) \
 189         do { printk(KERN_INFO NS_OUTPUT_PREFIX " " args); } while(0)
 190
 191 /* Busy-wait delay macros (microseconds, milliseconds) */
 192 #define NS_UDELAY(us) \
 193         do { if (do_delays) udelay(us); } while(0)
 194 #define NS_MDELAY(us) \
 195         do { if (do_delays) mdelay(us); } while(0)
 196
 197 /* Is the nandsim structure initialized ? */
 198 #define NS_IS_INITIALIZED(ns) ((ns)->geom.totsz != 0)
 199
 200 /* Good operation completion status */
 201 #define NS_STATUS_OK(ns) (NAND_STATUS_READY | (NAND_STATUS_WP * ((ns)->lines.wp == 0)))
 202
 203 /* Operation failed completion status */
 204 #define NS_STATUS_FAILED(ns) (NAND_STATUS_FAIL | NS_STATUS_OK(ns))
 205
 206 /* Calculate the page offset in flash RAM image by (row, column) address */
 207 #define NS_RAW_OFFSET(ns) \
 208         (((ns)->regs.row << (ns)->geom.pgshift) + ((ns)->regs.row * (ns)->geom.oobsz) + (ns)->regs.column)
 209
 210 /* Calculate the OOB offset in flash RAM image by (row, column) address */
 211 #define NS_RAW_OFFSET_OOB(ns) (NS_RAW_OFFSET(ns) + ns->geom.pgsz)
 212
 213 /* After a command is input, the simulator goes to one of the following states */
 214 #define STATE_CMD_READ0        0x00000001 /* read data from the beginning of page */
 215 #define STATE_CMD_READ1        0x00000002 /* read data from the second half of page */
 216 #define STATE_CMD_READSTART    0x00000003 /* read data second command (large page devices) */
 217 #define STATE_CMD_PAGEPROG     0x00000004 /* start page program */
 218 #define STATE_CMD_READOOB      0x00000005 /* read OOB area */
 219 #define STATE_CMD_ERASE1       0x00000006 /* sector erase first command */
 220 #define STATE_CMD_STATUS       0x00000007 /* read status */
 221 #define STATE_CMD_STATUS_M     0x00000008 /* read multi-plane status (isn't implemented) */
 222 #define STATE_CMD_SEQIN        0x00000009 /* sequential data input */
 223 #define STATE_CMD_READID       0x0000000A /* read ID */
 224 #define STATE_CMD_ERASE2       0x0000000B /* sector erase second command */
 225 #define STATE_CMD_RESET        0x0000000C /* reset */
 226 #define STATE_CMD_RNDOUT       0x0000000D /* random output command */
 227 #define STATE_CMD_RNDOUTSTART  0x0000000E /* random output start command */
 228 #define STATE_CMD_MASK         0x0000000F /* command states mask */
 229
 230 /* After an address is input, the simulator goes to one of these states */
 231 #define STATE_ADDR_PAGE        0x00000010 /* full (row, column) address is accepted */
 232 #define STATE_ADDR_SEC         0x00000020 /* sector address was accepted */
 233 #define STATE_ADDR_COLUMN      0x00000030 /* column address was accepted */
 234 #define STATE_ADDR_ZERO        0x00000040 /* one byte zero address was accepted */
 235 #define STATE_ADDR_MASK        0x00000070 /* address states mask */
 236
 237 /* During data input/output the simulator is in these states */
 238 #define STATE_DATAIN           0x00000100 /* waiting for data input */
 239 #define STATE_DATAIN_MASK      0x00000100 /* data input states mask */
 240
 241 #define STATE_DATAOUT          0x00001000 /* waiting for page data output */
 242 #define STATE_DATAOUT_ID       0x00002000 /* waiting for ID bytes output */
 243 #define STATE_DATAOUT_STATUS   0x00003000 /* waiting for status output */
 244 #define STATE_DATAOUT_STATUS_M 0x00004000 /* waiting for multi-plane status output */
 245 #define STATE_DATAOUT_MASK     0x00007000 /* data output states mask */
 246
 247 /* Previous operation is done, ready to accept new requests */
 248 #define STATE_READY            0x00000000
 249
 250 /* This state is used to mark that the next state isn't known yet */
 251 #define STATE_UNKNOWN          0x10000000
 252
 253 /* Simulator's actions bit masks */
 254 #define ACTION_CPY       0x00100000 /* copy page/OOB to the internal buffer */
 255 #define ACTION_PRGPAGE   0x00200000 /* program the internal buffer to flash */
 256 #define ACTION_SECERASE  0x00300000 /* erase sector */
 257 #define ACTION_ZEROOFF   0x00400000 /* don't add any offset to address */
 258 #define ACTION_HALFOFF   0x00500000 /* add to address half of page */
 259 #define ACTION_OOBOFF    0x00600000 /* add to address OOB offset */
 260 #define ACTION_MASK      0x00700000 /* action mask */
 261
 262 #define NS_OPER_NUM      13 /* Number of operations supported by the simulator */
 263 #define NS_OPER_STATES   6  /* Maximum number of states in operation */
 264
 265 #define OPT_ANY          0xFFFFFFFF /* any chip supports this operation */
 266 #define OPT_PAGE256      0x00000001 /* 256-byte  page chips */
 267 #define OPT_PAGE512      0x00000002 /* 512-byte  page chips */
 268 #define OPT_PAGE2048     0x00000008 /* 2048-byte page chips */
 269 #define OPT_SMARTMEDIA   0x00000010 /* SmartMedia technology chips */
 270 #define OPT_PAGE512_8BIT 0x00000040 /* 512-byte page chips with 8-bit bus width */
 271 #define OPT_PAGE4096     0x00000080 /* 4096-byte page chips */
 272 #define OPT_LARGEPAGE    (OPT_PAGE2048 | OPT_PAGE4096) /* 2048 & 4096-byte page chips */
 273 #define OPT_SMALLPAGE    (OPT_PAGE256  | OPT_PAGE512)  /* 256 and 512-byte page chips */
 274
 275 /* Remove action bits from state */
 276 #define NS_STATE(x) ((x) & ~ACTION_MASK)
 277
 278 /*
 279  * Maximum previous states which need to be saved. Currently saving is
 280  * only needed for page program operation with preceded read command
 281  * (which is only valid for 512-byte pages).
 282  */
 283 #define NS_MAX_PREVSTATES 1
 284
 285 /* Maximum page cache pages needed to read or write a NAND page to the cache_file */
 286 #define NS_MAX_HELD_PAGES 16
 287
 288 struct nandsim_debug_info {
 289         struct dentry *dfs_root;
 290         struct dentry *dfs_wear_report;
 291 };
 292
 293 /*
 294  * A union to represent flash memory contents and flash buffer.
 295  */
 296 union ns_mem {
 297         u_char *byte;    /* for byte access */
 298         uint16_t *word;  /* for 16-bit word access */
 299 };
 300
 301 /*
 302  * The structure which describes all the internal simulator data.
 303  */
 304 struct nandsim {
 305         struct mtd_partition partitions[CONFIG_NANDSIM_MAX_PARTS];
 306         unsigned int nbparts;
 307
 308         uint busw;              /* flash chip bus width (8 or 16) */
 309         u_char ids[4];          /* chip's ID bytes */
 310         uint32_t options;       /* chip's characteristic bits */
 311         uint32_t state;         /* current chip state */
 312         uint32_t nxstate;       /* next expected state */
 313
 314         uint32_t *op;           /* current operation, NULL operations isn't known yet  */
 315         uint32_t pstates[NS_MAX_PREVSTATES]; /* previous states */
 316         uint16_t npstates;      /* number of previous states saved */
 317         uint16_t stateidx;      /* current state index */
 318
 319         /* The simulated NAND flash pages array */
 320         union ns_mem *pages;
 321
 322         /* Slab allocator for nand pages */
 323         struct kmem_cache *nand_pages_slab;
 324
 325         /* Internal buffer of page + OOB size bytes */
 326         union ns_mem buf;
 327
 328         /* NAND flash "geometry" */
 329         struct {
 330                 uint64_t totsz;     /* total flash size, bytes */
 331                 uint32_t secsz;     /* flash sector (erase block) size, bytes */
 332                 uint pgsz;          /* NAND flash page size, bytes */
 333                 uint oobsz;         /* page OOB area size, bytes */
 334                 uint64_t totszoob;  /* total flash size including OOB, bytes */
 335                 uint pgszoob;       /* page size including OOB , bytes*/
 336                 uint secszoob;      /* sector size including OOB, bytes */
 337                 uint pgnum;         /* total number of pages */
 338                 uint pgsec;         /* number of pages per sector */
 339                 uint secshift;      /* bits number in sector size */
 340                 uint pgshift;       /* bits number in page size */
 341                 uint oobshift;      /* bits number in OOB size */
 342                 uint pgaddrbytes;   /* bytes per page address */
 343                 uint secaddrbytes;  /* bytes per sector address */
 344                 uint idbytes;       /* the number ID bytes that this chip outputs */
 345         } geom;
 346
 347         /* NAND flash internal registers */
 348         struct {
 349                 unsigned command; /* the command register */
 350                 u_char   status;  /* the status register */
 351                 uint     row;     /* the page number */
 352                 uint     column;  /* the offset within page */
 353                 uint     count;   /* internal counter */
 354                 uint     num;     /* number of bytes which must be processed */
 355                 uint     off;     /* fixed page offset */
 356         } regs;
 357
 358         /* NAND flash lines state */
 359         struct {
 360                 int ce;  /* chip Enable */
 361                 int cle; /* command Latch Enable */
 362                 int ale; /* address Latch Enable */
 363                 int wp;  /* write Protect */
 364         } lines;
 365
 366         /* Fields needed when using a cache file */
 367         struct file *cfile; /* Open file */
 368         unsigned char *pages_written; /* Which pages have been written */
 369         void *file_buf;
 370         struct page *held_pages[NS_MAX_HELD_PAGES];
 371         int held_cnt;
 372
 373         struct nandsim_debug_info dbg;
 374 };
 375
 376 /*
 377  * Operations array. To perform any operation the simulator must pass
 378  * through the correspondent states chain.
 379  */
 380 static struct nandsim_operations {
 381         uint32_t reqopts;  /* options which are required to perform the operation */
 382         uint32_t states[NS_OPER_STATES]; /* operation's states */
 383 } ops[NS_OPER_NUM] = {
 384         /* Read page + OOB from the beginning */
 385         {OPT_SMALLPAGE, {STATE_CMD_READ0 | ACTION_ZEROOFF, STATE_ADDR_PAGE | ACTION_CPY,
 386                         STATE_DATAOUT, STATE_READY}},
 387         /* Read page + OOB from the second half */
 388         {OPT_PAGE512_8BIT, {STATE_CMD_READ1 | ACTION_HALFOFF, STATE_ADDR_PAGE | ACTION_CPY,
 389                         STATE_DATAOUT, STATE_READY}},
 390         /* Read OOB */
 391         {OPT_SMALLPAGE, {STATE_CMD_READOOB | ACTION_OOBOFF, STATE_ADDR_PAGE | ACTION_CPY,
 392                         STATE_DATAOUT, STATE_READY}},
 393         /* Program page starting from the beginning */
 394         {OPT_ANY, {STATE_CMD_SEQIN, STATE_ADDR_PAGE, STATE_DATAIN,
 395                         STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},
 396         /* Program page starting from the beginning */
 397         {OPT_SMALLPAGE, {STATE_CMD_READ0, STATE_CMD_SEQIN | ACTION_ZEROOFF, STATE_ADDR_PAGE,
 398                               STATE_DATAIN, STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},
 399         /* Program page starting from the second half */
 400         {OPT_PAGE512, {STATE_CMD_READ1, STATE_CMD_SEQIN | ACTION_HALFOFF, STATE_ADDR_PAGE,
 401                               STATE_DATAIN, STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},
 402         /* Program OOB */
 403         {OPT_SMALLPAGE, {STATE_CMD_READOOB, STATE_CMD_SEQIN | ACTION_OOBOFF, STATE_ADDR_PAGE,
 404                               STATE_DATAIN, STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},
 405         /* Erase sector */
 406         {OPT_ANY, {STATE_CMD_ERASE1, STATE_ADDR_SEC, STATE_CMD_ERASE2 | ACTION_SECERASE, STATE_READY}},
 407         /* Read status */
 408         {OPT_ANY, {STATE_CMD_STATUS, STATE_DATAOUT_STATUS, STATE_READY}},
 409         /* Read multi-plane status */
 410         {OPT_SMARTMEDIA, {STATE_CMD_STATUS_M, STATE_DATAOUT_STATUS_M, STATE_READY}},
 411         /* Read ID */
 412         {OPT_ANY, {STATE_CMD_READID, STATE_ADDR_ZERO, STATE_DATAOUT_ID, STATE_READY}},
 413         /* Large page devices read page */
 414         {OPT_LARGEPAGE, {STATE_CMD_READ0, STATE_ADDR_PAGE, STATE_CMD_READSTART | ACTION_CPY,
 415                                STATE_DATAOUT, STATE_READY}},
 416         /* Large page devices random page read */
 417         {OPT_LARGEPAGE, {STATE_CMD_RNDOUT, STATE_ADDR_COLUMN, STATE_CMD_RNDOUTSTART | ACTION_CPY,
 418                                STATE_DATAOUT, STATE_READY}},
 419 };
 420
 421 struct weak_block {
 422         struct list_head list;
 423         unsigned int erase_block_no;
 424         unsigned int max_erases;
 425         unsigned int erases_done;
 426 };
 427
 428 static LIST_HEAD(weak_blocks);
 429
 430 struct weak_page {
 431         struct list_head list;
 432         unsigned int page_no;
 433         unsigned int max_writes;
 434         unsigned int writes_done;
 435 };
 436
 437 static LIST_HEAD(weak_pages);
 438
 439 struct grave_page {
 440         struct list_head list;
 441         unsigned int page_no;
 442         unsigned int max_reads;
 443         unsigned int reads_done;
 444 };
 445
 446 static LIST_HEAD(grave_pages);
 447
 448 static unsigned long *erase_block_wear = NULL;
 449 static unsigned int wear_eb_count = 0;
 450 static unsigned long total_wear = 0;
 451
 452 /* MTD structure for NAND controller */
 453 static struct mtd_info *nsmtd;
 454
 455 static int nandsim_debugfs_show(struct seq_file *m, void *private)
 456 {
 457         unsigned long wmin = -1, wmax = 0, avg;
 458         unsigned long deciles[10], decile_max[10], tot = 0;
 459         unsigned int i;
 460
 461         /* Calc wear stats */
 462         for (i = 0; i < wear_eb_count; ++i) {
 463                 unsigned long wear = erase_block_wear[i];
 464                 if (wear < wmin)
 465                         wmin = wear;
 466                 if (wear > wmax)
 467                         wmax = wear;
 468                 tot += wear;
 469         }
 470
 471         for (i = 0; i < 9; ++i) {
 472                 deciles[i] = 0;
 473                 decile_max[i] = (wmax * (i + 1) + 5) / 10;
 474         }
 475         deciles[9] = 0;
 476         decile_max[9] = wmax;
 477         for (i = 0; i < wear_eb_count; ++i) {
 478                 int d;
 479                 unsigned long wear = erase_block_wear[i];
 480                 for (d = 0; d < 10; ++d)
 481                         if (wear <= decile_max[d]) {
 482                                 deciles[d] += 1;
 483                                 break;
 484                         }
 485         }
 486         avg = tot / wear_eb_count;
 487
 488         /* Output wear report */
 489         seq_printf(m, "Total numbers of erases:  %lu\n", tot);
 490         seq_printf(m, "Number of erase blocks:   %u\n", wear_eb_count);
 491         seq_printf(m, "Average number of erases: %lu\n", avg);
 492         seq_printf(m, "Maximum number of erases: %lu\n", wmax);
 493         seq_printf(m, "Minimum number of erases: %lu\n", wmin);
 494         for (i = 0; i < 10; ++i) {
 495                 unsigned long from = (i ? decile_max[i - 1] + 1 : 0);
 496                 if (from > decile_max[i])
 497                         continue;
 498                 seq_printf(m, "Number of ebs with erase counts from %lu to %lu : %lu\n",
 499                         from,
 500                         decile_max[i],
 501                         deciles[i]);
 502         }
 503
 504         return 0;
 505 }
 506
 507 static int nandsim_debugfs_open(struct inode *inode, struct file *file)
 508 {
 509         return single_open(file, nandsim_debugfs_show, inode->i_private);
 510 }
 511
 512 static const struct file_operations dfs_fops = {
 513         .open           = nandsim_debugfs_open,
 514         .read           = seq_read,
 515         .llseek         = seq_lseek,
 516         .release        = single_release,
 517 };
 518
 519 /**
 520  * nandsim_debugfs_create - initialize debugfs
 521  * @dev: nandsim device description object
 522  *
 523  * This function creates all debugfs files for UBI device @ubi. Returns zero in
 524  * case of success and a negative error code in case of failure.
 525  */
 526 static int nandsim_debugfs_create(struct nandsim *dev)
 527 {
 528         struct nandsim_debug_info *dbg = &dev->dbg;
 529         struct dentry *dent;
 530         int err;
 531
 532         if (!IS_ENABLED(CONFIG_DEBUG_FS))
 533                 return 0;
 534
 535         dent = debugfs_create_dir("nandsim", NULL);
 536         if (IS_ERR_OR_NULL(dent)) {
 537                 int err = dent ? -ENODEV : PTR_ERR(dent);
 538
 539                 NS_ERR("cannot create \"nandsim\" debugfs directory, err %d\n",
 540                         err);
 541                 return err;
 542         }
 543         dbg->dfs_root = dent;
 544
 545         dent = debugfs_create_file("wear_report", S_IRUSR,
 546                                    dbg->dfs_root, dev, &dfs_fops);
 547         if (IS_ERR_OR_NULL(dent))
 548                 goto out_remove;
 549         dbg->dfs_wear_report = dent;
 550
 551         return 0;
 552
 553 out_remove:
 554         debugfs_remove_recursive(dbg->dfs_root);
 555         err = dent ? PTR_ERR(dent) : -ENODEV;
 556         return err;
 557 }
 558
 559 /**
 560  * nandsim_debugfs_remove - destroy all debugfs files
 561  */
 562 static void nandsim_debugfs_remove(struct nandsim *ns)
 563 {
 564         if (IS_ENABLED(CONFIG_DEBUG_FS))
 565                 debugfs_remove_recursive(ns->dbg.dfs_root);
 566 }
 567
 568 /*
 569  * Allocate array of page pointers, create slab allocation for an array
 570  * and initialize the array by NULL pointers.
 571  *
 572  * RETURNS: 0 if success, -ENOMEM if memory alloc fails.
 573  */
 574 static int alloc_device(struct nandsim *ns)
 575 {
 576         struct file *cfile;
 577         int i, err;
 578
 579         if (cache_file) {
 580                 cfile = filp_open(cache_file, O_CREAT | O_RDWR | O_LARGEFILE, 0600);
 581                 if (IS_ERR(cfile))
 582                         return PTR_ERR(cfile);
 583                 if (!cfile->f_op || (!cfile->f_op->read && !cfile->f_op->aio_read)) {
 584                         NS_ERR("alloc_device: cache file not readable\n");
 585                         err = -EINVAL;
 586                         goto err_close;
 587                 }
 588                 if (!cfile->f_op->write && !cfile->f_op->aio_write) {
 589                         NS_ERR("alloc_device: cache file not writeable\n");
 590                         err = -EINVAL;
 591                         goto err_close;
 592                 }
 593                 ns->pages_written = vzalloc(ns->geom.pgnum);
 594                 if (!ns->pages_written) {
 595                         NS_ERR("alloc_device: unable to allocate pages written array\n");
 596                         err = -ENOMEM;
 597                         goto err_close;
 598                 }
 599                 ns->file_buf = kmalloc(ns->geom.pgszoob, GFP_KERNEL);
 600                 if (!ns->file_buf) {
 601                         NS_ERR("alloc_device: unable to allocate file buf\n");
 602                         err = -ENOMEM;
 603                         goto err_free;
 604                 }
 605                 ns->cfile = cfile;
 606                 return 0;
 607         }
 608
 609         ns->pages = vmalloc(ns->geom.pgnum * sizeof(union ns_mem));
 610         if (!ns->pages) {
 611                 NS_ERR("alloc_device: unable to allocate page array\n");
 612                 return -ENOMEM;
 613         }
 614         for (i = 0; i < ns->geom.pgnum; i++) {
 615                 ns->pages[i].byte = NULL;
 616         }
 617         ns->nand_pages_slab = kmem_cache_create("nandsim",
 618                                                 ns->geom.pgszoob, 0, 0, NULL);
 619         if (!ns->nand_pages_slab) {
 620                 NS_ERR("cache_create: unable to create kmem_cache\n");
 621                 return -ENOMEM;
 622         }
 623
 624         return 0;
 625
 626 err_free:
 627         vfree(ns->pages_written);
 628 err_close:
 629         filp_close(cfile, NULL);
 630         return err;
 631 }
 632
 633 /*
 634  * Free any allocated pages, and free the array of page pointers.
 635  */
 636 static void free_device(struct nandsim *ns)
 637 {
 638         int i;
 639
 640         if (ns->cfile) {
 641                 kfree(ns->file_buf);
 642                 vfree(ns->pages_written);
 643                 filp_close(ns->cfile, NULL);
 644                 return;
 645         }
 646
 647         if (ns->pages) {
 648                 for (i = 0; i < ns->geom.pgnum; i++) {
 649                         if (ns->pages[i].byte)
 650                                 kmem_cache_free(ns->nand_pages_slab,
 651                                                 ns->pages[i].byte);
 652                 }
 653                 kmem_cache_destroy(ns->nand_pages_slab);
 654                 vfree(ns->pages);
 655         }
 656 }
 657
 658 static char *get_partition_name(int i)
 659 {
 660         char buf[64];
 661         sprintf(buf, "NAND simulator partition %d", i);
 662         return kstrdup(buf, GFP_KERNEL);
 663 }
 664
 665 /*
 666  * Initialize the nandsim structure.
 667  *
 668  * RETURNS: 0 if success, -ERRNO if failure.
 669  */
 670 static int init_nandsim(struct mtd_info *mtd)
 671 {
 672         struct nand_chip *chip = mtd->priv;
 673         struct nandsim   *ns   = chip->priv;
 674         int i, ret = 0;
 675         uint64_t remains;
 676         uint64_t next_offset;
 677
 678         if (NS_IS_INITIALIZED(ns)) {
 679                 NS_ERR("init_nandsim: nandsim is already initialized\n");
 680                 return -EIO;
 681         }
 682
 683         /* Force mtd to not do delays */
 684         chip->chip_delay = 0;
 685
 686         /* Initialize the NAND flash parameters */
 687         ns->busw = chip->options & NAND_BUSWIDTH_16 ? 16 : 8;
 688         ns->geom.totsz    = mtd->size;
 689         ns->geom.pgsz     = mtd->writesize;
 690         ns->geom.oobsz    = mtd->oobsize;
 691         ns->geom.secsz    = mtd->erasesize;
 692         ns->geom.pgszoob  = ns->geom.pgsz + ns->geom.oobsz;
 693         ns->geom.pgnum    = div_u64(ns->geom.totsz, ns->geom.pgsz);
 694         ns->geom.totszoob = ns->geom.totsz + (uint64_t)ns->geom.pgnum * ns->geom.oobsz;
 695         ns->geom.secshift = ffs(ns->geom.secsz) - 1;
 696         ns->geom.pgshift  = chip->page_shift;
 697         ns->geom.oobshift = ffs(ns->geom.oobsz) - 1;
 698         ns->geom.pgsec    = ns->geom.secsz / ns->geom.pgsz;
 699         ns->geom.secszoob = ns->geom.secsz + ns->geom.oobsz * ns->geom.pgsec;
 700         ns->options = 0;
 701
 702         if (ns->geom.pgsz == 256) {
 703                 ns->options |= OPT_PAGE256;
 704         }
 705         else if (ns->geom.pgsz == 512) {
 706                 ns->options |= OPT_PAGE512;
 707                 if (ns->busw == 8)
 708                         ns->options |= OPT_PAGE512_8BIT;
 709         } else if (ns->geom.pgsz == 2048) {
 710                 ns->options |= OPT_PAGE2048;
 711         } else if (ns->geom.pgsz == 4096) {
 712                 ns->options |= OPT_PAGE4096;
 713         } else {
 714                 NS_ERR("init_nandsim: unknown page size %u\n", ns->geom.pgsz);
 715                 return -EIO;
 716         }
 717
 718         if (ns->options & OPT_SMALLPAGE) {
 719                 if (ns->geom.totsz <= (32 << 20)) {
 720                         ns->geom.pgaddrbytes  = 3;
 721                         ns->geom.secaddrbytes = 2;
 722                 } else {
 723                         ns->geom.pgaddrbytes  = 4;
 724                         ns->geom.secaddrbytes = 3;
 725                 }
 726         } else {
 727                 if (ns->geom.totsz <= (128 << 20)) {
 728                         ns->geom.pgaddrbytes  = 4;
 729                         ns->geom.secaddrbytes = 2;
 730                 } else {
 731                         ns->geom.pgaddrbytes  = 5;
 732                         ns->geom.secaddrbytes = 3;
 733                 }
 734         }
 735
 736         /* Fill the partition_info structure */
 737         if (parts_num > ARRAY_SIZE(ns->partitions)) {
 738                 NS_ERR("too many partitions.\n");
 739                 ret = -EINVAL;
 740                 goto error;
 741         }
 742         remains = ns->geom.totsz;
 743         next_offset = 0;
 744         for (i = 0; i < parts_num; ++i) {
 745                 uint64_t part_sz = (uint64_t)parts[i] * ns->geom.secsz;
 746
 747                 if (!part_sz || part_sz > remains) {
 748                         NS_ERR("bad partition size.\n");
 749                         ret = -EINVAL;
 750                         goto error;
 751                 }
 752                 ns->partitions[i].name   = get_partition_name(i);
 753                 ns->partitions[i].offset = next_offset;
 754                 ns->partitions[i].size   = part_sz;
 755                 next_offset += ns->partitions[i].size;
 756                 remains -= ns->partitions[i].size;
 757         }
 758         ns->nbparts = parts_num;
 759         if (remains) {
 760                 if (parts_num + 1 > ARRAY_SIZE(ns->partitions)) {
 761                         NS_ERR("too many partitions.\n");
 762                         ret = -EINVAL;
 763                         goto error;
 764                 }
 765                 ns->partitions[i].name   = get_partition_name(i);
 766                 ns->partitions[i].offset = next_offset;
 767                 ns->partitions[i].size   = remains;
 768                 ns->nbparts += 1;
 769         }
 770
 771         /* Detect how many ID bytes the NAND chip outputs */
 772         for (i = 0; nand_flash_ids[i].name != NULL; i++) {
 773                 if (second_id_byte != nand_flash_ids[i].id)
 774                         continue;
 775         }
 776
 777         if (ns->busw == 16)
 778                 NS_WARN("16-bit flashes support wasn't tested\n");
 779
 780         printk("flash size: %llu MiB\n",
 781                         (unsigned long long)ns->geom.totsz >> 20);
 782         printk("page size: %u bytes\n",         ns->geom.pgsz);
 783         printk("OOB area size: %u bytes\n",     ns->geom.oobsz);
 784         printk("sector size: %u KiB\n",         ns->geom.secsz >> 10);
 785         printk("pages number: %u\n",            ns->geom.pgnum);
 786         printk("pages per sector: %u\n",        ns->geom.pgsec);
 787         printk("bus width: %u\n",               ns->busw);
 788         printk("bits in sector size: %u\n",     ns->geom.secshift);
 789         printk("bits in page size: %u\n",       ns->geom.pgshift);
 790         printk("bits in OOB size: %u\n",        ns->geom.oobshift);
 791         printk("flash size with OOB: %llu KiB\n",
 792                         (unsigned long long)ns->geom.totszoob >> 10);
 793         printk("page address bytes: %u\n",      ns->geom.pgaddrbytes);
 794         printk("sector address bytes: %u\n",    ns->geom.secaddrbytes);
 795         printk("options: %#x\n",                ns->options);
 796
 797         if ((ret = alloc_device(ns)) != 0)
 798                 goto error;
 799
 800         /* Allocate / initialize the internal buffer */
 801         ns->buf.byte = kmalloc(ns->geom.pgszoob, GFP_KERNEL);
 802         if (!ns->buf.byte) {
 803                 NS_ERR("init_nandsim: unable to allocate %u bytes for the internal buffer\n",
 804                         ns->geom.pgszoob);
 805                 ret = -ENOMEM;
 806                 goto error;
 807         }
 808         memset(ns->buf.byte, 0xFF, ns->geom.pgszoob);
 809
 810         return 0;
 811
 812 error:
 813         free_device(ns);
 814
 815         return ret;
 816 }
 817
 818 /*
 819  * Free the nandsim structure.
 820  */
 821 static void free_nandsim(struct nandsim *ns)
 822 {
 823         kfree(ns->buf.byte);
 824         free_device(ns);
 825
 826         return;
 827 }
 828
 829 static int parse_badblocks(struct nandsim *ns, struct mtd_info *mtd)
 830 {
 831         char *w;
 832         int zero_ok;
 833         unsigned int erase_block_no;
 834         loff_t offset;
 835
 836         if (!badblocks)
 837                 return 0;
 838         w = badblocks;
 839         do {
 840                 zero_ok = (*w == '0' ? 1 : 0);
 841                 erase_block_no = simple_strtoul(w, &w, 0);
 842                 if (!zero_ok && !erase_block_no) {
 843                         NS_ERR("invalid badblocks.\n");
 844                         return -EINVAL;
 845                 }
 846                 offset = erase_block_no * ns->geom.secsz;
 847                 if (mtd_block_markbad(mtd, offset)) {
 848                         NS_ERR("invalid badblocks.\n");
 849                         return -EINVAL;
 850                 }
 851                 if (*w == ',')
 852                         w += 1;
 853         } while (*w);
 854         return 0;
 855 }
 856
 857 static int parse_weakblocks(void)
 858 {
 859         char *w;
 860         int zero_ok;
 861         unsigned int erase_block_no;
 862         unsigned int max_erases;
 863         struct weak_block *wb;
 864
 865         if (!weakblocks)
 866                 return 0;
 867         w = weakblocks;
 868         do {
 869                 zero_ok = (*w == '0' ? 1 : 0);
 870                 erase_block_no = simple_strtoul(w, &w, 0);
 871                 if (!zero_ok && !erase_block_no) {
 872                         NS_ERR("invalid weakblocks.\n");
 873                         return -EINVAL;
 874                 }
 875                 max_erases = 3;
 876                 if (*w == ':') {
 877                         w += 1;
 878                         max_erases = simple_strtoul(w, &w, 0);
 879                 }
 880                 if (*w == ',')
 881                         w += 1;
 882                 wb = kzalloc(sizeof(*wb), GFP_KERNEL);
 883                 if (!wb) {
 884                         NS_ERR("unable to allocate memory.\n");
 885                         return -ENOMEM;
 886                 }
 887                 wb->erase_block_no = erase_block_no;
 888                 wb->max_erases = max_erases;
 889                 list_add(&wb->list, &weak_blocks);
 890         } while (*w);
 891         return 0;
 892 }
 893
 894 static int erase_error(unsigned int erase_block_no)
 895 {
 896         struct weak_block *wb;
 897
 898         list_for_each_entry(wb, &weak_blocks, list)
 899                 if (wb->erase_block_no == erase_block_no) {
 900                         if (wb->erases_done >= wb->max_erases)
 901                                 return 1;
 902                         wb->erases_done += 1;
 903                         return 0;
 904                 }
 905         return 0;
 906 }
 907
 908 static int parse_weakpages(void)
 909 {
 910         char *w;
 911         int zero_ok;
 912         unsigned int page_no;
 913         unsigned int max_writes;
 914         struct weak_page *wp;
 915
 916         if (!weakpages)
 917                 return 0;
 918         w = weakpages;
 919         do {
 920                 zero_ok = (*w == '0' ? 1 : 0);
 921                 page_no = simple_strtoul(w, &w, 0);
 922                 if (!zero_ok && !page_no) {
 923                         NS_ERR("invalid weakpagess.\n");
 924                         return -EINVAL;
 925                 }
 926                 max_writes = 3;
 927                 if (*w == ':') {
 928                         w += 1;
 929                         max_writes = simple_strtoul(w, &w, 0);
 930                 }
 931                 if (*w == ',')
 932                         w += 1;
 933                 wp = kzalloc(sizeof(*wp), GFP_KERNEL);
 934                 if (!wp) {
 935                         NS_ERR("unable to allocate memory.\n");
 936                         return -ENOMEM;
 937                 }
 938                 wp->page_no = page_no;
 939                 wp->max_writes = max_writes;
 940                 list_add(&wp->list, &weak_pages);
 941         } while (*w);
 942         return 0;
 943 }
 944
 945 static int write_error(unsigned int page_no)
 946 {
 947         struct weak_page *wp;
 948
 949         list_for_each_entry(wp, &weak_pages, list)
 950                 if (wp->page_no == page_no) {
 951                         if (wp->writes_done >= wp->max_writes)
 952                                 return 1;
 953                         wp->writes_done += 1;
 954                         return 0;
 955                 }
 956         return 0;
 957 }
 958
 959 static int parse_gravepages(void)
 960 {
 961         char *g;
 962         int zero_ok;
 963         unsigned int page_no;
 964         unsigned int max_reads;
 965         struct grave_page *gp;
 966
 967         if (!gravepages)
 968                 return 0;
 969         g = gravepages;
 970         do {
 971                 zero_ok = (*g == '0' ? 1 : 0);
 972                 page_no = simple_strtoul(g, &g, 0);
 973                 if (!zero_ok && !page_no) {
 974                         NS_ERR("invalid gravepagess.\n");
 975                         return -EINVAL;
 976                 }
 977                 max_reads = 3;
 978                 if (*g == ':') {
 979                         g += 1;
 980                         max_reads = simple_strtoul(g, &g, 0);
 981                 }
 982                 if (*g == ',')
 983                         g += 1;
 984                 gp = kzalloc(sizeof(*gp), GFP_KERNEL);
 985                 if (!gp) {
 986                         NS_ERR("unable to allocate memory.\n");
 987                         return -ENOMEM;
 988                 }
 989                 gp->page_no = page_no;
 990                 gp->max_reads = max_reads;
 991                 list_add(&gp->list, &grave_pages);
 992         } while (*g);
 993         return 0;
 994 }
 995
 996 static int read_error(unsigned int page_no)
 997 {
 998         struct grave_page *gp;
 999
1000         list_for_each_entry(gp, &grave_pages, list)
1001                 if (gp->page_no == page_no) {
1002                         if (gp->reads_done >= gp->max_reads)
1003                                 return 1;
1004                         gp->reads_done += 1;
1005                         return 0;
1006                 }
1007         return 0;
1008 }
1009
1010 static void free_lists(void)
1011 {
1012         struct list_head *pos, *n;
1013         list_for_each_safe(pos, n, &weak_blocks) {
1014                 list_del(pos);
1015                 kfree(list_entry(pos, struct weak_block, list));
1016         }
1017         list_for_each_safe(pos, n, &weak_pages) {
1018                 list_del(pos);
1019                 kfree(list_entry(pos, struct weak_page, list));
1020         }
1021         list_for_each_safe(pos, n, &grave_pages) {
1022                 list_del(pos);
1023                 kfree(list_entry(pos, struct grave_page, list));
1024         }
1025         kfree(erase_block_wear);
1026 }
1027
1028 static int setup_wear_reporting(struct mtd_info *mtd)
1029 {
1030         size_t mem;
1031
1032         wear_eb_count = div_u64(mtd->size, mtd->erasesize);
1033         mem = wear_eb_count * sizeof(unsigned long);
1034         if (mem / sizeof(unsigned long) != wear_eb_count) {
1035                 NS_ERR("Too many erase blocks for wear reporting\n");
1036                 return -ENOMEM;
1037         }
1038         erase_block_wear = kzalloc(mem, GFP_KERNEL);
1039         if (!erase_block_wear) {
1040                 NS_ERR("Too many erase blocks for wear reporting\n");
1041                 return -ENOMEM;
1042         }
1043         return 0;
1044 }
1045
1046 static void update_wear(unsigned int erase_block_no)
1047 {
1048         if (!erase_block_wear)
1049                 return;
1050         total_wear += 1;
1051         /*
1052          * TODO: Notify this through a debugfs entry,
1053          * instead of showing an error message.
1054          */
1055         if (total_wear == 0)
1056                 NS_ERR("Erase counter total overflow\n");
1057         erase_block_wear[erase_block_no] += 1;
1058         if (erase_block_wear[erase_block_no] == 0)
1059                 NS_ERR("Erase counter overflow for erase block %u\n", erase_block_no);
1060 }
1061
1062 /*
1063  * Returns the string representation of 'state' state.
1064  */
1065 static char *get_state_name(uint32_t state)
1066 {
1067         switch (NS_STATE(state)) {
1068                 case STATE_CMD_READ0:
1069                         return "STATE_CMD_READ0";
1070                 case STATE_CMD_READ1:
1071                         return "STATE_CMD_READ1";
1072                 case STATE_CMD_PAGEPROG:
1073                         return "STATE_CMD_PAGEPROG";
1074                 case STATE_CMD_READOOB:
1075                         return "STATE_CMD_READOOB";
1076                 case STATE_CMD_READSTART:
1077                         return "STATE_CMD_READSTART";
1078                 case STATE_CMD_ERASE1:
1079                         return "STATE_CMD_ERASE1";
1080                 case STATE_CMD_STATUS:
1081                         return "STATE_CMD_STATUS";
1082                 case STATE_CMD_STATUS_M:
1083                         return "STATE_CMD_STATUS_M";
1084                 case STATE_CMD_SEQIN:
1085                         return "STATE_CMD_SEQIN";
1086                 case STATE_CMD_READID:
1087                         return "STATE_CMD_READID";
1088                 case STATE_CMD_ERASE2:
1089                         return "STATE_CMD_ERASE2";
1090                 case STATE_CMD_RESET:
1091                         return "STATE_CMD_RESET";
1092                 case STATE_CMD_RNDOUT:
1093                         return "STATE_CMD_RNDOUT";
1094                 case STATE_CMD_RNDOUTSTART:
1095                         return "STATE_CMD_RNDOUTSTART";
1096                 case STATE_ADDR_PAGE:
1097                         return "STATE_ADDR_PAGE";
1098                 case STATE_ADDR_SEC:
1099                         return "STATE_ADDR_SEC";
1100                 case STATE_ADDR_ZERO:
1101                         return "STATE_ADDR_ZERO";
1102                 case STATE_ADDR_COLUMN:
1103                         return "STATE_ADDR_COLUMN";
1104                 case STATE_DATAIN:
1105                         return "STATE_DATAIN";
1106                 case STATE_DATAOUT:
1107                         return "STATE_DATAOUT";
1108                 case STATE_DATAOUT_ID:
1109                         return "STATE_DATAOUT_ID";
1110                 case STATE_DATAOUT_STATUS:
1111                         return "STATE_DATAOUT_STATUS";
1112                 case STATE_DATAOUT_STATUS_M:
1113                         return "STATE_DATAOUT_STATUS_M";
1114                 case STATE_READY:
1115                         return "STATE_READY";
1116                 case STATE_UNKNOWN:
1117                         return "STATE_UNKNOWN";
1118         }
1119
1120         NS_ERR("get_state_name: unknown state, BUG\n");
1121         return NULL;
1122 }
1123
1124 /*
1125  * Check if command is valid.
1126  *
1127  * RETURNS: 1 if wrong command, 0 if right.
1128  */
1129 static int check_command(int cmd)
1130 {
1131         switch (cmd) {
1132
1133         case NAND_CMD_READ0:
1134         case NAND_CMD_READ1:
1135         case NAND_CMD_READSTART:
1136         case NAND_CMD_PAGEPROG:
1137         case NAND_CMD_READOOB:
1138         case NAND_CMD_ERASE1:
1139         case NAND_CMD_STATUS:
1140         case NAND_CMD_SEQIN:
1141         case NAND_CMD_READID:
1142         case NAND_CMD_ERASE2:
1143         case NAND_CMD_RESET:
1144         case NAND_CMD_RNDOUT:
1145         case NAND_CMD_RNDOUTSTART:
1146                 return 0;
1147
1148         case NAND_CMD_STATUS_MULTI:
1149         default:
1150                 return 1;
1151         }
1152 }
1153
1154 /*
1155  * Returns state after command is accepted by command number.
1156  */
1157 static uint32_t get_state_by_command(unsigned command)
1158 {
1159         switch (command) {
1160                 case NAND_CMD_READ0:
1161                         return STATE_CMD_READ0;
1162                 case NAND_CMD_READ1:
1163                         return STATE_CMD_READ1;
1164                 case NAND_CMD_PAGEPROG:
1165                         return STATE_CMD_PAGEPROG;
1166                 case NAND_CMD_READSTART:
1167                         return STATE_CMD_READSTART;
1168                 case NAND_CMD_READOOB:
1169                         return STATE_CMD_READOOB;
1170                 case NAND_CMD_ERASE1:
1171                         return STATE_CMD_ERASE1;
1172                 case NAND_CMD_STATUS:
1173                         return STATE_CMD_STATUS;
1174                 case NAND_CMD_STATUS_MULTI:
1175                         return STATE_CMD_STATUS_M;
1176                 case NAND_CMD_SEQIN:
1177                         return STATE_CMD_SEQIN;
1178                 case NAND_CMD_READID:
1179                         return STATE_CMD_READID;
1180                 case NAND_CMD_ERASE2:
1181                         return STATE_CMD_ERASE2;
1182                 case NAND_CMD_RESET:
1183                         return STATE_CMD_RESET;
1184                 case NAND_CMD_RNDOUT:
1185                         return STATE_CMD_RNDOUT;
1186                 case NAND_CMD_RNDOUTSTART:
1187                         return STATE_CMD_RNDOUTSTART;
1188         }
1189
1190         NS_ERR("get_state_by_command: unknown command, BUG\n");
1191         return 0;
1192 }
1193
1194 /*
1195  * Move an address byte to the correspondent internal register.
1196  */
1197 static inline void accept_addr_byte(struct nandsim *ns, u_char bt)
1198 {
1199         uint byte = (uint)bt;
1200
1201         if (ns->regs.count < (ns->geom.pgaddrbytes - ns->geom.secaddrbytes))
1202                 ns->regs.column |= (byte << 8 * ns->regs.count);
1203         else {
1204                 ns->regs.row |= (byte << 8 * (ns->regs.count -
1205                                                 ns->geom.pgaddrbytes +
1206                                                 ns->geom.secaddrbytes));
1207         }
1208
1209         return;
1210 }
1211
1212 /*
1213  * Switch to STATE_READY state.
1214  */
1215 static inline void switch_to_ready_state(struct nandsim *ns, u_char status)
1216 {
1217         NS_DBG("switch_to_ready_state: switch to %s state\n", get_state_name(STATE_READY));
1218
1219         ns->state       = STATE_READY;
1220         ns->nxstate     = STATE_UNKNOWN;
1221         ns->op          = NULL;
1222         ns->npstates    = 0;
1223         ns->stateidx    = 0;
1224         ns->regs.num    = 0;
1225         ns->regs.count  = 0;
1226         ns->regs.off    = 0;
1227         ns->regs.row    = 0;
1228         ns->regs.column = 0;
1229         ns->regs.status = status;
1230 }
1231
1232 /*
1233  * If the operation isn't known yet, try to find it in the global array
1234  * of supported operations.
1235  *
1236  * Operation can be unknown because of the following.
1237  *   1. New command was accepted and this is the first call to find the
1238  *      correspondent states chain. In this case ns->npstates = 0;
1239  *   2. There are several operations which begin with the same command(s)
1240  *      (for example program from the second half and read from the
1241  *      second half operations both begin with the READ1 command). In this
1242  *      case the ns->pstates[] array contains previous states.
1243  *
1244  * Thus, the function tries to find operation containing the following
1245  * states (if the 'flag' parameter is 0):
1246  *    ns->pstates[0], ... ns->pstates[ns->npstates], ns->state
1247  *
1248  * If (one and only one) matching operation is found, it is accepted (
1249  * ns->ops, ns->state, ns->nxstate are initialized, ns->npstate is
1250  * zeroed).
1251  *
1252  * If there are several matches, the current state is pushed to the
1253  * ns->pstates.
1254  *
1255  * The operation can be unknown only while commands are input to the chip.
1256  * As soon as address command is accepted, the operation must be known.
1257  * In such situation the function is called with 'flag' != 0, and the
1258  * operation is searched using the following pattern:
1259  *     ns->pstates[0], ... ns->pstates[ns->npstates], <address input>
1260  *
1261  * It is supposed that this pattern must either match one operation or
1262  * none. There can't be ambiguity in that case.
1263  *
1264  * If no matches found, the function does the following:
1265  *   1. if there are saved states present, try to ignore them and search
1266  *      again only using the last command. If nothing was found, switch
1267  *      to the STATE_READY state.
1268  *   2. if there are no saved states, switch to the STATE_READY state.
1269  *
1270  * RETURNS: -2 - no matched operations found.
1271  *          -1 - several matches.
1272  *           0 - operation is found.
1273  */
1274 static int find_operation(struct nandsim *ns, uint32_t flag)
1275 {
1276         int opsfound = 0;
1277         int i, j, idx = 0;
1278
1279         for (i = 0; i < NS_OPER_NUM; i++) {
1280
1281                 int found = 1;
1282
1283                 if (!(ns->options & ops[i].reqopts))
1284                         /* Ignore operations we can't perform */
1285                         continue;
1286
1287                 if (flag) {
1288                         if (!(ops[i].states[ns->npstates] & STATE_ADDR_MASK))
1289                                 continue;
1290                 } else {
1291                         if (NS_STATE(ns->state) != NS_STATE(ops[i].states[ns->npstates]))
1292                                 continue;
1293                 }
1294
1295                 for (j = 0; j < ns->npstates; j++)
1296                         if (NS_STATE(ops[i].states[j]) != NS_STATE(ns->pstates[j])
1297                                 && (ns->options & ops[idx].reqopts)) {
1298                                 found = 0;
1299                                 break;
1300                         }
1301
1302                 if (found) {
1303                         idx = i;
1304                         opsfound += 1;
1305                 }
1306         }
1307
1308         if (opsfound == 1) {
1309                 /* Exact match */
1310                 ns->op = &ops[idx].states[0];
1311                 if (flag) {
1312                         /*
1313                          * In this case the find_operation function was
1314                          * called when address has just began input. But it isn't
1315                          * yet fully input and the current state must
1316                          * not be one of STATE_ADDR_*, but the STATE_ADDR_*
1317                          * state must be the next state (ns->nxstate).
1318                          */
1319                         ns->stateidx = ns->npstates - 1;
1320                 } else {
1321                         ns->stateidx = ns->npstates;
1322                 }
1323                 ns->npstates = 0;
1324                 ns->state = ns->op[ns->stateidx];
1325                 ns->nxstate = ns->op[ns->stateidx + 1];
1326                 NS_DBG("find_operation: operation found, index: %d, state: %s, nxstate %s\n",
1327                                 idx, get_state_name(ns->state), get_state_name(ns->nxstate));
1328                 return 0;
1329         }
1330
1331         if (opsfound == 0) {
1332                 /* Nothing was found. Try to ignore previous commands (if any) and search again */
1333                 if (ns->npstates != 0) {
1334                         NS_DBG("find_operation: no operation found, try again with state %s\n",
1335                                         get_state_name(ns->state));
1336                         ns->npstates = 0;
1337                         return find_operation(ns, 0);
1338
1339                 }
1340                 NS_DBG("find_operation: no operations found\n");
1341                 switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1342                 return -2;
1343         }
1344
1345         if (flag) {
1346                 /* This shouldn't happen */
1347                 NS_DBG("find_operation: BUG, operation must be known if address is input\n");
1348                 return -2;
1349         }
1350
1351         NS_DBG("find_operation: there is still ambiguity\n");
1352
1353         ns->pstates[ns->npstates++] = ns->state;
1354
1355         return -1;
1356 }
1357
1358 static void put_pages(struct nandsim *ns)
1359 {
1360         int i;
1361
1362         for (i = 0; i < ns->held_cnt; i++)
1363                 page_cache_release(ns->held_pages[i]);
1364 }
1365
1366 /* Get page cache pages in advance to provide NOFS memory allocation */
1367 static int get_pages(struct nandsim *ns, struct file *file, size_t count, loff_t pos)
1368 {
1369         pgoff_t index, start_index, end_index;
1370         struct page *page;
1371         struct address_space *mapping = file->f_mapping;
1372
1373         start_index = pos >> PAGE_CACHE_SHIFT;
1374         end_index = (pos + count - 1) >> PAGE_CACHE_SHIFT;
1375         if (end_index - start_index + 1 > NS_MAX_HELD_PAGES)
1376                 return -EINVAL;
1377         ns->held_cnt = 0;
1378         for (index = start_index; index <= end_index; index++) {
1379                 page = find_get_page(mapping, index);
1380                 if (page == NULL) {
1381                         page = find_or_create_page(mapping, index, GFP_NOFS);
1382                         if (page == NULL) {
1383                                 write_inode_now(mapping->host, 1);
1384                                 page = find_or_create_page(mapping, index, GFP_NOFS);
1385                         }
1386                         if (page == NULL) {
1387                                 put_pages(ns);
1388                                 return -ENOMEM;
1389                         }
1390                         unlock_page(page);
1391                 }
1392                 ns->held_pages[ns->held_cnt++] = page;
1393         }
1394         return 0;
1395 }
1396
1397 static int set_memalloc(void)
1398 {
1399         if (current->flags & PF_MEMALLOC)
1400                 return 0;
1401         current->flags |= PF_MEMALLOC;
1402         return 1;
1403 }
1404
1405 static void clear_memalloc(int memalloc)
1406 {
1407         if (memalloc)
1408                 current->flags &= ~PF_MEMALLOC;
1409 }
1410
1411 static ssize_t read_file(struct nandsim *ns, struct file *file, void *buf, size_t count, loff_t *pos)
1412 {
1413         mm_segment_t old_fs;
1414         ssize_t tx;
1415         int err, memalloc;
1416
1417         err = get_pages(ns, file, count, *pos);
1418         if (err)
1419                 return err;
1420         old_fs = get_fs();
1421         set_fs(get_ds());
1422         memalloc = set_memalloc();
1423         tx = vfs_read(file, (char __user *)buf, count, pos);
1424         clear_memalloc(memalloc);
1425         set_fs(old_fs);
1426         put_pages(ns);
1427         return tx;
1428 }
1429
1430 static ssize_t write_file(struct nandsim *ns, struct file *file, void *buf, size_t count, loff_t *pos)
1431 {
1432         mm_segment_t old_fs;
1433         ssize_t tx;
1434         int err, memalloc;
1435
1436         err = get_pages(ns, file, count, *pos);
1437         if (err)
1438                 return err;
1439         old_fs = get_fs();
1440         set_fs(get_ds());
1441         memalloc = set_memalloc();
1442         tx = vfs_write(file, (char __user *)buf, count, pos);
1443         clear_memalloc(memalloc);
1444         set_fs(old_fs);
1445         put_pages(ns);
1446         return tx;
1447 }
1448
1449 /*
1450  * Returns a pointer to the current page.
1451  */
1452 static inline union ns_mem *NS_GET_PAGE(struct nandsim *ns)
1453 {
1454         return &(ns->pages[ns->regs.row]);
1455 }
1456
1457 /*
1458  * Retuns a pointer to the current byte, within the current page.
1459  */
1460 static inline u_char *NS_PAGE_BYTE_OFF(struct nandsim *ns)
1461 {
1462         return NS_GET_PAGE(ns)->byte + ns->regs.column + ns->regs.off;
1463 }
1464
1465 int do_read_error(struct nandsim *ns, int num)
1466 {
1467         unsigned int page_no = ns->regs.row;
1468
1469         if (read_error(page_no)) {
1470                 prandom_bytes(ns->buf.byte, num);
1471                 NS_WARN("simulating read error in page %u\n", page_no);
1472                 return 1;
1473         }
1474         return 0;
1475 }
1476
1477 void do_bit_flips(struct nandsim *ns, int num)
1478 {
1479         if (bitflips && random32() < (1 << 22)) {
1480                 int flips = 1;
1481                 if (bitflips > 1)
1482                         flips = (random32() % (int) bitflips) + 1;
1483                 while (flips--) {
1484                         int pos = random32() % (num * 8);
1485                         ns->buf.byte[pos / 8] ^= (1 << (pos % 8));
1486                         NS_WARN("read_page: flipping bit %d in page %d "
1487                                 "reading from %d ecc: corrected=%u failed=%u\n",
1488                                 pos, ns->regs.row, ns->regs.column + ns->regs.off,
1489                                 nsmtd->ecc_stats.corrected, nsmtd->ecc_stats.failed);
1490                 }
1491         }
1492 }
1493
1494 /*
1495  * Fill the NAND buffer with data read from the specified page.
1496  */
1497 static void read_page(struct nandsim *ns, int num)
1498 {
1499         union ns_mem *mypage;
1500
1501         if (ns->cfile) {
1502                 if (!ns->pages_written[ns->regs.row]) {
1503                         NS_DBG("read_page: page %d not written\n", ns->regs.row);
1504                         memset(ns->buf.byte, 0xFF, num);
1505                 } else {
1506                         loff_t pos;
1507                         ssize_t tx;
1508
1509                         NS_DBG("read_page: page %d written, reading from %d\n",
1510                                 ns->regs.row, ns->regs.column + ns->regs.off);
1511                         if (do_read_error(ns, num))
1512                                 return;
1513                         pos = (loff_t)ns->regs.row * ns->geom.pgszoob + ns->regs.column + ns->regs.off;
1514                         tx = read_file(ns, ns->cfile, ns->buf.byte, num, &pos);
1515                         if (tx != num) {
1516                                 NS_ERR("read_page: read error for page %d ret %ld\n", ns->regs.row, (long)tx);
1517                                 return;
1518                         }
1519                         do_bit_flips(ns, num);
1520                 }
1521                 return;
1522         }
1523
1524         mypage = NS_GET_PAGE(ns);
1525         if (mypage->byte == NULL) {
1526                 NS_DBG("read_page: page %d not allocated\n", ns->regs.row);
1527                 memset(ns->buf.byte, 0xFF, num);
1528         } else {
1529                 NS_DBG("read_page: page %d allocated, reading from %d\n",
1530                         ns->regs.row, ns->regs.column + ns->regs.off);
1531                 if (do_read_error(ns, num))
1532                         return;
1533                 memcpy(ns->buf.byte, NS_PAGE_BYTE_OFF(ns), num);
1534                 do_bit_flips(ns, num);
1535         }
1536 }
1537
1538 /*
1539  * Erase all pages in the specified sector.
1540  */
1541 static void erase_sector(struct nandsim *ns)
1542 {
1543         union ns_mem *mypage;
1544         int i;
1545
1546         if (ns->cfile) {
1547                 for (i = 0; i < ns->geom.pgsec; i++)
1548                         if (ns->pages_written[ns->regs.row + i]) {
1549                                 NS_DBG("erase_sector: freeing page %d\n", ns->regs.row + i);
1550                                 ns->pages_written[ns->regs.row + i] = 0;
1551                         }
1552                 return;
1553         }
1554
1555         mypage = NS_GET_PAGE(ns);
1556         for (i = 0; i < ns->geom.pgsec; i++) {
1557                 if (mypage->byte != NULL) {
1558                         NS_DBG("erase_sector: freeing page %d\n", ns->regs.row+i);
1559                         kmem_cache_free(ns->nand_pages_slab, mypage->byte);
1560                         mypage->byte = NULL;
1561                 }
1562                 mypage++;
1563         }
1564 }
1565
1566 /*
1567  * Program the specified page with the contents from the NAND buffer.
1568  */
1569 static int prog_page(struct nandsim *ns, int num)
1570 {
1571         int i;
1572         union ns_mem *mypage;
1573         u_char *pg_off;
1574
1575         if (ns->cfile) {
1576                 loff_t off, pos;
1577                 ssize_t tx;
1578                 int all;
1579
1580                 NS_DBG("prog_page: writing page %d\n", ns->regs.row);
1581                 pg_off = ns->file_buf + ns->regs.column + ns->regs.off;
1582                 off = (loff_t)ns->regs.row * ns->geom.pgszoob + ns->regs.column + ns->regs.off;
1583                 if (!ns->pages_written[ns->regs.row]) {
1584                         all = 1;
1585                         memset(ns->file_buf, 0xff, ns->geom.pgszoob);
1586                 } else {
1587                         all = 0;
1588                         pos = off;
1589                         tx = read_file(ns, ns->cfile, pg_off, num, &pos);
1590                         if (tx != num) {
1591                                 NS_ERR("prog_page: read error for page %d ret %ld\n", ns->regs.row, (long)tx);
1592                                 return -1;
1593                         }
1594                 }
1595                 for (i = 0; i < num; i++)
1596                         pg_off[i] &= ns->buf.byte[i];
1597                 if (all) {
1598                         pos = (loff_t)ns->regs.row * ns->geom.pgszoob;
1599                         tx = write_file(ns, ns->cfile, ns->file_buf, ns->geom.pgszoob, &pos);
1600                         if (tx != ns->geom.pgszoob) {
1601                                 NS_ERR("prog_page: write error for page %d ret %ld\n", ns->regs.row, (long)tx);
1602                                 return -1;
1603                         }
1604                         ns->pages_written[ns->regs.row] = 1;
1605                 } else {
1606                         pos = off;
1607                         tx = write_file(ns, ns->cfile, pg_off, num, &pos);
1608                         if (tx != num) {
1609                                 NS_ERR("prog_page: write error for page %d ret %ld\n", ns->regs.row, (long)tx);
1610                                 return -1;
1611                         }
1612                 }
1613                 return 0;
1614         }
1615
1616         mypage = NS_GET_PAGE(ns);
1617         if (mypage->byte == NULL) {
1618                 NS_DBG("prog_page: allocating page %d\n", ns->regs.row);
1619                 /*
1620                  * We allocate memory with GFP_NOFS because a flash FS may
1621                  * utilize this. If it is holding an FS lock, then gets here,
1622                  * then kernel memory alloc runs writeback which goes to the FS
1623                  * again and deadlocks. This was seen in practice.
1624                  */
1625                 mypage->byte = kmem_cache_alloc(ns->nand_pages_slab, GFP_NOFS);
1626                 if (mypage->byte == NULL) {
1627                         NS_ERR("prog_page: error allocating memory for page %d\n", ns->regs.row);
1628                         return -1;
1629                 }
1630                 memset(mypage->byte, 0xFF, ns->geom.pgszoob);
1631         }
1632
1633         pg_off = NS_PAGE_BYTE_OFF(ns);
1634         for (i = 0; i < num; i++)
1635                 pg_off[i] &= ns->buf.byte[i];
1636
1637         return 0;
1638 }
1639
1640 /*
1641  * If state has any action bit, perform this action.
1642  *
1643  * RETURNS: 0 if success, -1 if error.
1644  */
1645 static int do_state_action(struct nandsim *ns, uint32_t action)
1646 {
1647         int num;
1648         int busdiv = ns->busw == 8 ? 1 : 2;
1649         unsigned int erase_block_no, page_no;
1650
1651         action &= ACTION_MASK;
1652
1653         /* Check that page address input is correct */
1654         if (action != ACTION_SECERASE && ns->regs.row >= ns->geom.pgnum) {
1655                 NS_WARN("do_state_action: wrong page number (%#x)\n", ns->regs.row);
1656                 return -1;
1657         }
1658
1659         switch (action) {
1660
1661         case ACTION_CPY:
1662                 /*
1663                  * Copy page data to the internal buffer.
1664                  */
1665
1666                 /* Column shouldn't be very large */
1667                 if (ns->regs.column >= (ns->geom.pgszoob - ns->regs.off)) {
1668                         NS_ERR("do_state_action: column number is too large\n");
1669                         break;
1670                 }
1671                 num = ns->geom.pgszoob - ns->regs.off - ns->regs.column;
1672                 read_page(ns, num);
1673
1674                 NS_DBG("do_state_action: (ACTION_CPY:) copy %d bytes to int buf, raw offset %d\n",
1675                         num, NS_RAW_OFFSET(ns) + ns->regs.off);
1676
1677                 if (ns->regs.off == 0)
1678                         NS_LOG("read page %d\n", ns->regs.row);
1679                 else if (ns->regs.off < ns->geom.pgsz)
1680                         NS_LOG("read page %d (second half)\n", ns->regs.row);
1681                 else
1682                         NS_LOG("read OOB of page %d\n", ns->regs.row);
1683
1684                 NS_UDELAY(access_delay);
1685                 NS_UDELAY(input_cycle * ns->geom.pgsz / 1000 / busdiv);
1686
1687                 break;
1688
1689         case ACTION_SECERASE:
1690                 /*
1691                  * Erase sector.
1692                  */
1693
1694                 if (ns->lines.wp) {
1695                         NS_ERR("do_state_action: device is write-protected, ignore sector erase\n");
1696                         return -1;
1697                 }
1698
1699                 if (ns->regs.row >= ns->geom.pgnum - ns->geom.pgsec
1700                         || (ns->regs.row & ~(ns->geom.secsz - 1))) {
1701                         NS_ERR("do_state_action: wrong sector address (%#x)\n", ns->regs.row);
1702                         return -1;
1703                 }
1704
1705                 ns->regs.row = (ns->regs.row <<
1706                                 8 * (ns->geom.pgaddrbytes - ns->geom.secaddrbytes)) | ns->regs.column;
1707                 ns->regs.column = 0;
1708
1709                 erase_block_no = ns->regs.row >> (ns->geom.secshift - ns->geom.pgshift);
1710
1711                 NS_DBG("do_state_action: erase sector at address %#x, off = %d\n",
1712                                 ns->regs.row, NS_RAW_OFFSET(ns));
1713                 NS_LOG("erase sector %u\n", erase_block_no);
1714
1715                 erase_sector(ns);
1716
1717                 NS_MDELAY(erase_delay);
1718
1719                 if (erase_block_wear)
1720                         update_wear(erase_block_no);
1721
1722                 if (erase_error(erase_block_no)) {
1723                         NS_WARN("simulating erase failure in erase block %u\n", erase_block_no);
1724                         return -1;
1725                 }
1726
1727                 break;
1728
1729         case ACTION_PRGPAGE:
1730                 /*
1731                  * Program page - move internal buffer data to the page.
1732                  */
1733
1734                 if (ns->lines.wp) {
1735                         NS_WARN("do_state_action: device is write-protected, programm\n");
1736                         return -1;
1737                 }
1738
1739                 num = ns->geom.pgszoob - ns->regs.off - ns->regs.column;
1740                 if (num != ns->regs.count) {
1741                         NS_ERR("do_state_action: too few bytes were input (%d instead of %d)\n",
1742                                         ns->regs.count, num);
1743                         return -1;
1744                 }
1745
1746                 if (prog_page(ns, num) == -1)
1747                         return -1;
1748
1749                 page_no = ns->regs.row;
1750
1751                 NS_DBG("do_state_action: copy %d bytes from int buf to (%#x, %#x), raw off = %d\n",
1752                         num, ns->regs.row, ns->regs.column, NS_RAW_OFFSET(ns) + ns->regs.off);
1753                 NS_LOG("programm page %d\n", ns->regs.row);
1754
1755                 NS_UDELAY(programm_delay);
1756                 NS_UDELAY(output_cycle * ns->geom.pgsz / 1000 / busdiv);
1757
1758                 if (write_error(page_no)) {
1759                         NS_WARN("simulating write failure in page %u\n", page_no);
1760                         return -1;
1761                 }
1762
1763                 break;
1764
1765         case ACTION_ZEROOFF:
1766                 NS_DBG("do_state_action: set internal offset to 0\n");
1767                 ns->regs.off = 0;
1768                 break;
1769
1770         case ACTION_HALFOFF:
1771                 if (!(ns->options & OPT_PAGE512_8BIT)) {
1772                         NS_ERR("do_state_action: BUG! can't skip half of page for non-512"
1773                                 "byte page size 8x chips\n");
1774                         return -1;
1775                 }
1776                 NS_DBG("do_state_action: set internal offset to %d\n", ns->geom.pgsz/2);
1777                 ns->regs.off = ns->geom.pgsz/2;
1778                 break;
1779
1780         case ACTION_OOBOFF:
1781                 NS_DBG("do_state_action: set internal offset to %d\n", ns->geom.pgsz);
1782                 ns->regs.off = ns->geom.pgsz;
1783                 break;
1784
1785         default:
1786                 NS_DBG("do_state_action: BUG! unknown action\n");
1787         }
1788
1789         return 0;
1790 }
1791
1792 /*
1793  * Switch simulator's state.
1794  */
1795 static void switch_state(struct nandsim *ns)
1796 {
1797         if (ns->op) {
1798                 /*
1799                  * The current operation have already been identified.
1800                  * Just follow the states chain.
1801                  */
1802
1803                 ns->stateidx += 1;
1804                 ns->state = ns->nxstate;
1805                 ns->nxstate = ns->op[ns->stateidx + 1];
1806
1807                 NS_DBG("switch_state: operation is known, switch to the next state, "
1808                         "state: %s, nxstate: %s\n",
1809                         get_state_name(ns->state), get_state_name(ns->nxstate));
1810
1811                 /* See, whether we need to do some action */
1812                 if ((ns->state & ACTION_MASK) && do_state_action(ns, ns->state) < 0) {
1813                         switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1814                         return;
1815                 }
1816
1817         } else {
1818                 /*
1819                  * We don't yet know which operation we perform.
1820                  * Try to identify it.
1821                  */
1822
1823                 /*
1824                  *  The only event causing the switch_state function to
1825                  *  be called with yet unknown operation is new command.
1826                  */
1827                 ns->state = get_state_by_command(ns->regs.command);
1828
1829                 NS_DBG("switch_state: operation is unknown, try to find it\n");
1830
1831                 if (find_operation(ns, 0) != 0)
1832                         return;
1833
1834                 if ((ns->state & ACTION_MASK) && do_state_action(ns, ns->state) < 0) {
1835                         switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1836                         return;
1837                 }
1838         }
1839
1840         /* For 16x devices column means the page offset in words */
1841         if ((ns->nxstate & STATE_ADDR_MASK) && ns->busw == 16) {
1842                 NS_DBG("switch_state: double the column number for 16x device\n");
1843                 ns->regs.column <<= 1;
1844         }
1845
1846         if (NS_STATE(ns->nxstate) == STATE_READY) {
1847                 /*
1848                  * The current state is the last. Return to STATE_READY
1849                  */
1850
1851                 u_char status = NS_STATUS_OK(ns);
1852
1853                 /* In case of data states, see if all bytes were input/output */
1854                 if ((ns->state & (STATE_DATAIN_MASK | STATE_DATAOUT_MASK))
1855                         && ns->regs.count != ns->regs.num) {
1856                         NS_WARN("switch_state: not all bytes were processed, %d left\n",
1857                                         ns->regs.num - ns->regs.count);
1858                         status = NS_STATUS_FAILED(ns);
1859                 }
1860
1861                 NS_DBG("switch_state: operation complete, switch to STATE_READY state\n");
1862
1863                 switch_to_ready_state(ns, status);
1864
1865                 return;
1866         } else if (ns->nxstate & (STATE_DATAIN_MASK | STATE_DATAOUT_MASK)) {
1867                 /*
1868                  * If the next state is data input/output, switch to it now
1869                  */
1870
1871                 ns->state      = ns->nxstate;
1872                 ns->nxstate    = ns->op[++ns->stateidx + 1];
1873                 ns->regs.num   = ns->regs.count = 0;
1874
1875                 NS_DBG("switch_state: the next state is data I/O, switch, "
1876                         "state: %s, nxstate: %s\n",
1877                         get_state_name(ns->state), get_state_name(ns->nxstate));
1878
1879                 /*
1880                  * Set the internal register to the count of bytes which
1881                  * are expected to be input or output
1882                  */
1883                 switch (NS_STATE(ns->state)) {
1884                         case STATE_DATAIN:
1885                         case STATE_DATAOUT:
1886                                 ns->regs.num = ns->geom.pgszoob - ns->regs.off - ns->regs.column;
1887                                 break;
1888
1889                         case STATE_DATAOUT_ID:
1890                                 ns->regs.num = ns->geom.idbytes;
1891                                 break;
1892
1893                         case STATE_DATAOUT_STATUS:
1894                         case STATE_DATAOUT_STATUS_M:
1895                                 ns->regs.count = ns->regs.num = 0;
1896                                 break;
1897
1898                         default:
1899                                 NS_ERR("switch_state: BUG! unknown data state\n");
1900                 }
1901
1902         } else if (ns->nxstate & STATE_ADDR_MASK) {
1903                 /*
1904                  * If the next state is address input, set the internal
1905                  * register to the number of expected address bytes
1906                  */
1907
1908                 ns->regs.count = 0;
1909
1910                 switch (NS_STATE(ns->nxstate)) {
1911                         case STATE_ADDR_PAGE:
1912                                 ns->regs.num = ns->geom.pgaddrbytes;
1913
1914                                 break;
1915                         case STATE_ADDR_SEC:
1916                                 ns->regs.num = ns->geom.secaddrbytes;
1917                                 break;
1918
1919                         case STATE_ADDR_ZERO:
1920                                 ns->regs.num = 1;
1921                                 break;
1922
1923                         case STATE_ADDR_COLUMN:
1924                                 /* Column address is always 2 bytes */
1925                                 ns->regs.num = ns->geom.pgaddrbytes - ns->geom.secaddrbytes;
1926                                 break;
1927
1928                         default:
1929                                 NS_ERR("switch_state: BUG! unknown address state\n");
1930                 }
1931         } else {
1932                 /*
1933                  * Just reset internal counters.
1934                  */
1935
1936                 ns->regs.num = 0;
1937                 ns->regs.count = 0;
1938         }
1939 }
1940
1941 static u_char ns_nand_read_byte(struct mtd_info *mtd)
1942 {
1943         struct nandsim *ns = ((struct nand_chip *)mtd->priv)->priv;
1944         u_char outb = 0x00;
1945
1946         /* Sanity and correctness checks */
1947         if (!ns->lines.ce) {
1948                 NS_ERR("read_byte: chip is disabled, return %#x\n", (uint)outb);
1949                 return outb;
1950         }
1951         if (ns->lines.ale || ns->lines.cle) {
1952                 NS_ERR("read_byte: ALE or CLE pin is high, return %#x\n", (uint)outb);
1953                 return outb;
1954         }
1955         if (!(ns->state & STATE_DATAOUT_MASK)) {
1956                 NS_WARN("read_byte: unexpected data output cycle, state is %s "
1957                         "return %#x\n", get_state_name(ns->state), (uint)outb);
1958                 return outb;
1959         }
1960
1961         /* Status register may be read as many times as it is wanted */
1962         if (NS_STATE(ns->state) == STATE_DATAOUT_STATUS) {
1963                 NS_DBG("read_byte: return %#x status\n", ns->regs.status);
1964                 return ns->regs.status;
1965         }
1966
1967         /* Check if there is any data in the internal buffer which may be read */
1968         if (ns->regs.count == ns->regs.num) {
1969                 NS_WARN("read_byte: no more data to output, return %#x\n", (uint)outb);
1970                 return outb;
1971         }
1972
1973         switch (NS_STATE(ns->state)) {
1974                 case STATE_DATAOUT:
1975                         if (ns->busw == 8) {
1976                                 outb = ns->buf.byte[ns->regs.count];
1977                                 ns->regs.count += 1;
1978                         } else {
1979                                 outb = (u_char)cpu_to_le16(ns->buf.word[ns->regs.count >> 1]);
1980                                 ns->regs.count += 2;
1981                         }
1982                         break;
1983                 case STATE_DATAOUT_ID:
1984                         NS_DBG("read_byte: read ID byte %d, total = %d\n", ns->regs.count, ns->regs.num);
1985                         outb = ns->ids[ns->regs.count];
1986                         ns->regs.count += 1;
1987                         break;
1988                 default:
1989                         BUG();
1990         }
1991
1992         if (ns->regs.count == ns->regs.num) {
1993                 NS_DBG("read_byte: all bytes were read\n");
1994
1995                 if (NS_STATE(ns->nxstate) == STATE_READY)
1996                         switch_state(ns);
1997         }
1998
1999         return outb;
2000 }
2001
2002 static void ns_nand_write_byte(struct mtd_info *mtd, u_char byte)
2003 {
2004         struct nandsim *ns = ((struct nand_chip *)mtd->priv)->priv;
2005
2006         /* Sanity and correctness checks */
2007         if (!ns->lines.ce) {
2008                 NS_ERR("write_byte: chip is disabled, ignore write\n");
2009                 return;
2010         }
2011         if (ns->lines.ale && ns->lines.cle) {
2012                 NS_ERR("write_byte: ALE and CLE pins are high simultaneously, ignore write\n");
2013                 return;
2014         }
2015
2016         if (ns->lines.cle == 1) {
2017                 /*
2018                  * The byte written is a command.
2019                  */
2020
2021                 if (byte == NAND_CMD_RESET) {
2022                         NS_LOG("reset chip\n");
2023                         switch_to_ready_state(ns, NS_STATUS_OK(ns));
2024                         return;
2025                 }
2026
2027                 /* Check that the command byte is correct */
2028                 if (check_command(byte)) {
2029                         NS_ERR("write_byte: unknown command %#x\n", (uint)byte);
2030                         return;
2031                 }
2032
2033                 if (NS_STATE(ns->state) == STATE_DATAOUT_STATUS
2034                         || NS_STATE(ns->state) == STATE_DATAOUT_STATUS_M
2035                         || NS_STATE(ns->state) == STATE_DATAOUT) {
2036                         int row = ns->regs.row;
2037
2038                         switch_state(ns);
2039                         if (byte == NAND_CMD_RNDOUT)
2040                                 ns->regs.row = row;
2041                 }
2042
2043                 /* Check if chip is expecting command */
2044                 if (NS_STATE(ns->nxstate) != STATE_UNKNOWN && !(ns->nxstate & STATE_CMD_MASK)) {
2045                         /* Do not warn if only 2 id bytes are read */
2046                         if (!(ns->regs.command == NAND_CMD_READID &&
2047                             NS_STATE(ns->state) == STATE_DATAOUT_ID && ns->regs.count == 2)) {
2048                                 /*
2049                                  * We are in situation when something else (not command)
2050                                  * was expected but command was input. In this case ignore
2051                                  * previous command(s)/state(s) and accept the last one.
2052                                  */
2053                                 NS_WARN("write_byte: command (%#x) wasn't expected, expected state is %s, "
2054                                         "ignore previous states\n", (uint)byte, get_state_name(ns->nxstate));
2055                         }
2056                         switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2057                 }
2058
2059                 NS_DBG("command byte corresponding to %s state accepted\n",
2060                         get_state_name(get_state_by_command(byte)));
2061                 ns->regs.command = byte;
2062                 switch_state(ns);
2063
2064         } else if (ns->lines.ale == 1) {
2065                 /*
2066                  * The byte written is an address.
2067                  */
2068
2069                 if (NS_STATE(ns->nxstate) == STATE_UNKNOWN) {
2070
2071                         NS_DBG("write_byte: operation isn't known yet, identify it\n");
2072
2073                         if (find_operation(ns, 1) < 0)
2074                                 return;
2075
2076                         if ((ns->state & ACTION_MASK) && do_state_action(ns, ns->state) < 0) {
2077                                 switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2078                                 return;
2079                         }
2080
2081                         ns->regs.count = 0;
2082                         switch (NS_STATE(ns->nxstate)) {
2083                                 case STATE_ADDR_PAGE:
2084                                         ns->regs.num = ns->geom.pgaddrbytes;
2085                                         break;
2086                                 case STATE_ADDR_SEC:
2087                                         ns->regs.num = ns->geom.secaddrbytes;
2088                                         break;
2089                                 case STATE_ADDR_ZERO:
2090                                         ns->regs.num = 1;
2091                                         break;
2092                                 default:
2093                                         BUG();
2094                         }
2095                 }
2096
2097                 /* Check that chip is expecting address */
2098                 if (!(ns->nxstate & STATE_ADDR_MASK)) {
2099                         NS_ERR("write_byte: address (%#x) isn't expected, expected state is %s, "
2100                                 "switch to STATE_READY\n", (uint)byte, get_state_name(ns->nxstate));
2101                         switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2102                         return;
2103                 }
2104
2105                 /* Check if this is expected byte */
2106                 if (ns->regs.count == ns->regs.num) {
2107                         NS_ERR("write_byte: no more address bytes expected\n");
2108                         switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2109                         return;
2110                 }
2111
2112                 accept_addr_byte(ns, byte);
2113
2114                 ns->regs.count += 1;
2115
2116                 NS_DBG("write_byte: address byte %#x was accepted (%d bytes input, %d expected)\n",
2117                                 (uint)byte, ns->regs.count, ns->regs.num);
2118
2119                 if (ns->regs.count == ns->regs.num) {
2120                         NS_DBG("address (%#x, %#x) is accepted\n", ns->regs.row, ns->regs.column);
2121                         switch_state(ns);
2122                 }
2123
2124         } else {
2125                 /*
2126                  * The byte written is an input data.
2127                  */
2128
2129                 /* Check that chip is expecting data input */
2130                 if (!(ns->state & STATE_DATAIN_MASK)) {
2131                         NS_ERR("write_byte: data input (%#x) isn't expected, state is %s, "
2132                                 "switch to %s\n", (uint)byte,
2133                                 get_state_name(ns->state), get_state_name(STATE_READY));
2134                         switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2135                         return;
2136                 }
2137
2138                 /* Check if this is expected byte */
2139                 if (ns->regs.count == ns->regs.num) {
2140                         NS_WARN("write_byte: %u input bytes has already been accepted, ignore write\n",
2141                                         ns->regs.num);
2142                         return;
2143                 }
2144
2145                 if (ns->busw == 8) {
2146                         ns->buf.byte[ns->regs.count] = byte;
2147                         ns->regs.count += 1;
2148                 } else {
2149                         ns->buf.word[ns->regs.count >> 1] = cpu_to_le16((uint16_t)byte);
2150                         ns->regs.count += 2;
2151                 }
2152         }
2153
2154         return;
2155 }
2156
2157 static void ns_hwcontrol(struct mtd_info *mtd, int cmd, unsigned int bitmask)
2158 {
2159         struct nandsim *ns = ((struct nand_chip *)mtd->priv)->priv;
2160
2161         ns->lines.cle = bitmask & NAND_CLE ? 1 : 0;
2162         ns->lines.ale = bitmask & NAND_ALE ? 1 : 0;
2163         ns->lines.ce = bitmask & NAND_NCE ? 1 : 0;
2164
2165         if (cmd != NAND_CMD_NONE)
2166                 ns_nand_write_byte(mtd, cmd);
2167 }
2168
2169 static int ns_device_ready(struct mtd_info *mtd)
2170 {
2171         NS_DBG("device_ready\n");
2172         return 1;
2173 }
2174
2175 static uint16_t ns_nand_read_word(struct mtd_info *mtd)
2176 {
2177         struct nand_chip *chip = (struct nand_chip *)mtd->priv;
2178
2179         NS_DBG("read_word\n");
2180
2181         return chip->read_byte(mtd) | (chip->read_byte(mtd) << 8);
2182 }
2183
2184 static void ns_nand_write_buf(struct mtd_info *mtd, const u_char *buf, int len)
2185 {
2186         struct nandsim *ns = ((struct nand_chip *)mtd->priv)->priv;
2187
2188         /* Check that chip is expecting data input */
2189         if (!(ns->state & STATE_DATAIN_MASK)) {
2190                 NS_ERR("write_buf: data input isn't expected, state is %s, "
2191                         "switch to STATE_READY\n", get_state_name(ns->state));
2192                 switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2193                 return;
2194         }
2195
2196         /* Check if these are expected bytes */
2197         if (ns->regs.count + len > ns->regs.num) {
2198                 NS_ERR("write_buf: too many input bytes\n");
2199                 switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2200                 return;
2201         }
2202
2203         memcpy(ns->buf.byte + ns->regs.count, buf, len);
2204         ns->regs.count += len;
2205
2206         if (ns->regs.count == ns->regs.num) {
2207                 NS_DBG("write_buf: %d bytes were written\n", ns->regs.count);
2208         }
2209 }
2210
2211 static void ns_nand_read_buf(struct mtd_info *mtd, u_char *buf, int len)
2212 {
2213         struct nandsim *ns = ((struct nand_chip *)mtd->priv)->priv;
2214
2215         /* Sanity and correctness checks */
2216         if (!ns->lines.ce) {
2217                 NS_ERR("read_buf: chip is disabled\n");
2218                 return;
2219         }
2220         if (ns->lines.ale || ns->lines.cle) {
2221                 NS_ERR("read_buf: ALE or CLE pin is high\n");
2222                 return;
2223         }
2224         if (!(ns->state & STATE_DATAOUT_MASK)) {
2225                 NS_WARN("read_buf: unexpected data output cycle, current state is %s\n",
2226                         get_state_name(ns->state));
2227                 return;
2228         }
2229
2230         if (NS_STATE(ns->state) != STATE_DATAOUT) {
2231                 int i;
2232
2233                 for (i = 0; i < len; i++)
2234                         buf[i] = ((struct nand_chip *)mtd->priv)->read_byte(mtd);
2235
2236                 return;
2237         }
2238
2239         /* Check if these are expected bytes */
2240         if (ns->regs.count + len > ns->regs.num) {
2241                 NS_ERR("read_buf: too many bytes to read\n");
2242                 switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2243                 return;
2244         }
2245
2246         memcpy(buf, ns->buf.byte + ns->regs.count, len);
2247         ns->regs.count += len;
2248
2249         if (ns->regs.count == ns->regs.num) {
2250                 if (NS_STATE(ns->nxstate) == STATE_READY)
2251                         switch_state(ns);
2252         }
2253
2254         return;
2255 }
2256
2257 /*
2258  * Module initialization function
2259  */
2260 static int __init ns_init_module(void)
2261 {
2262         struct nand_chip *chip;
2263         struct nandsim *nand;
2264         int retval = -ENOMEM, i;
2265
2266         if (bus_width != 8 && bus_width != 16) {
2267                 NS_ERR("wrong bus width (%d), use only 8 or 16\n", bus_width);
2268                 return -EINVAL;
2269         }
2270
2271         /* Allocate and initialize mtd_info, nand_chip and nandsim structures */
2272         nsmtd = kzalloc(sizeof(struct mtd_info) + sizeof(struct nand_chip)
2273                                 + sizeof(struct nandsim), GFP_KERNEL);
2274         if (!nsmtd) {
2275                 NS_ERR("unable to allocate core structures.\n");
2276                 return -ENOMEM;
2277         }
2278         chip        = (struct nand_chip *)(nsmtd + 1);
2279         nsmtd->priv = (void *)chip;
2280         nand        = (struct nandsim *)(chip + 1);
2281         chip->priv  = (void *)nand;
2282
2283         /*
2284          * Register simulator's callbacks.
2285          */
2286         chip->cmd_ctrl   = ns_hwcontrol;
2287         chip->read_byte  = ns_nand_read_byte;
2288         chip->dev_ready  = ns_device_ready;
2289         chip->write_buf  = ns_nand_write_buf;
2290         chip->read_buf   = ns_nand_read_buf;
2291         chip->read_word  = ns_nand_read_word;
2292         chip->ecc.mode   = NAND_ECC_SOFT;
2293         /* The NAND_SKIP_BBTSCAN option is necessary for 'overridesize' */
2294         /* and 'badblocks' parameters to work */
2295         chip->options   |= NAND_SKIP_BBTSCAN;
2296
2297         switch (bbt) {
2298         case 2:
2299                  chip->bbt_options |= NAND_BBT_NO_OOB;
2300         case 1:
2301                  chip->bbt_options |= NAND_BBT_USE_FLASH;
2302         case 0:
2303                 break;
2304         default:
2305                 NS_ERR("bbt has to be 0..2\n");
2306                 retval = -EINVAL;
2307                 goto error;
2308         }
2309         /*
2310          * Perform minimum nandsim structure initialization to handle
2311          * the initial ID read command correctly
2312          */
2313         if (third_id_byte != 0xFF || fourth_id_byte != 0xFF)
2314                 nand->geom.idbytes = 4;
2315         else
2316                 nand->geom.idbytes = 2;
2317         nand->regs.status = NS_STATUS_OK(nand);
2318         nand->nxstate = STATE_UNKNOWN;
2319         nand->options |= OPT_PAGE256; /* temporary value */
2320         nand->ids[0] = first_id_byte;
2321         nand->ids[1] = second_id_byte;
2322         nand->ids[2] = third_id_byte;
2323         nand->ids[3] = fourth_id_byte;
2324         if (bus_width == 16) {
2325                 nand->busw = 16;
2326                 chip->options |= NAND_BUSWIDTH_16;
2327         }
2328
2329         nsmtd->owner = THIS_MODULE;
2330
2331         if ((retval = parse_weakblocks()) != 0)
2332                 goto error;
2333
2334         if ((retval = parse_weakpages()) != 0)
2335                 goto error;
2336
2337         if ((retval = parse_gravepages()) != 0)
2338                 goto error;
2339
2340         retval = nand_scan_ident(nsmtd, 1, NULL);
2341         if (retval) {
2342                 NS_ERR("cannot scan NAND Simulator device\n");
2343                 if (retval > 0)
2344                         retval = -ENXIO;
2345                 goto error;
2346         }
2347
2348         if (bch) {
2349                 unsigned int eccsteps, eccbytes;
2350                 if (!mtd_nand_has_bch()) {
2351                         NS_ERR("BCH ECC support is disabled\n");
2352                         retval = -EINVAL;
2353                         goto error;
2354                 }
2355                 /* use 512-byte ecc blocks */
2356                 eccsteps = nsmtd->writesize/512;
2357                 eccbytes = (bch*13+7)/8;
2358                 /* do not bother supporting small page devices */
2359                 if ((nsmtd->oobsize < 64) || !eccsteps) {
2360                         NS_ERR("bch not available on small page devices\n");
2361                         retval = -EINVAL;
2362                         goto error;
2363                 }
2364                 if ((eccbytes*eccsteps+2) > nsmtd->oobsize) {
2365                         NS_ERR("invalid bch value %u\n", bch);
2366                         retval = -EINVAL;
2367                         goto error;
2368                 }
2369                 chip->ecc.mode = NAND_ECC_SOFT_BCH;
2370                 chip->ecc.size = 512;
2371                 chip->ecc.bytes = eccbytes;
2372                 NS_INFO("using %u-bit/%u bytes BCH ECC\n", bch, chip->ecc.size);
2373         }
2374
2375         retval = nand_scan_tail(nsmtd);
2376         if (retval) {
2377                 NS_ERR("can't register NAND Simulator\n");
2378                 if (retval > 0)
2379                         retval = -ENXIO;
2380                 goto error;
2381         }
2382
2383         if (overridesize) {
2384                 uint64_t new_size = (uint64_t)nsmtd->erasesize << overridesize;
2385                 if (new_size >> overridesize != nsmtd->erasesize) {
2386                         NS_ERR("overridesize is too big\n");
2387                         retval = -EINVAL;
2388                         goto err_exit;
2389                 }
2390                 /* N.B. This relies on nand_scan not doing anything with the size before we change it */
2391                 nsmtd->size = new_size;
2392                 chip->chipsize = new_size;
2393                 chip->chip_shift = ffs(nsmtd->erasesize) + overridesize - 1;
2394                 chip->pagemask = (chip->chipsize >> chip->page_shift) - 1;
2395         }
2396
2397         if ((retval = setup_wear_reporting(nsmtd)) != 0)
2398                 goto err_exit;
2399
2400         if ((retval = nandsim_debugfs_create(nand)) != 0)
2401                 goto err_exit;
2402
2403         if ((retval = init_nandsim(nsmtd)) != 0)
2404                 goto err_exit;
2405
2406         if ((retval = nand_default_bbt(nsmtd)) != 0)
2407                 goto err_exit;
2408
2409         if ((retval = parse_badblocks(nand, nsmtd)) != 0)
2410                 goto err_exit;
2411
2412         /* Register NAND partitions */
2413         retval = mtd_device_register(nsmtd, &nand->partitions[0],
2414                                      nand->nbparts);
2415         if (retval != 0)
2416                 goto err_exit;
2417
2418         return 0;
2419
2420 err_exit:
2421         free_nandsim(nand);
2422         nand_release(nsmtd);
2423         for (i = 0;i < ARRAY_SIZE(nand->partitions); ++i)
2424                 kfree(nand->partitions[i].name);
2425 error:
2426         kfree(nsmtd);
2427         free_lists();
2428
2429         return retval;
2430 }
2431
2432 module_init(ns_init_module);
2433
2434 /*
2435  * Module clean-up function
2436  */
2437 static void __exit ns_cleanup_module(void)
2438 {
2439         struct nandsim *ns = ((struct nand_chip *)nsmtd->priv)->priv;
2440         int i;
2441
2442         nandsim_debugfs_remove(ns);
2443         free_nandsim(ns);    /* Free nandsim private resources */
2444         nand_release(nsmtd); /* Unregister driver */
2445         for (i = 0;i < ARRAY_SIZE(ns->partitions); ++i)
2446                 kfree(ns->partitions[i].name);
2447         kfree(nsmtd);        /* Free other structures */
2448         free_lists();
2449 }
2450
2451 module_exit(ns_cleanup_module);
2452
2453 MODULE_LICENSE ("GPL");
2454 MODULE_AUTHOR ("Artem B. Bityuckiy");
2455 MODULE_DESCRIPTION ("The NAND flash simulator");