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_SEQIN        0x00000009 /* sequential data input */
 222 #define STATE_CMD_READID       0x0000000A /* read ID */
 223 #define STATE_CMD_ERASE2       0x0000000B /* sector erase second command */
 224 #define STATE_CMD_RESET        0x0000000C /* reset */
 225 #define STATE_CMD_RNDOUT       0x0000000D /* random output command */
 226 #define STATE_CMD_RNDOUTSTART  0x0000000E /* random output start command */
 227 #define STATE_CMD_MASK         0x0000000F /* command states mask */
 228
 229 /* After an address is input, the simulator goes to one of these states */
 230 #define STATE_ADDR_PAGE        0x00000010 /* full (row, column) address is accepted */
 231 #define STATE_ADDR_SEC         0x00000020 /* sector address was accepted */
 232 #define STATE_ADDR_COLUMN      0x00000030 /* column address was accepted */
 233 #define STATE_ADDR_ZERO        0x00000040 /* one byte zero address was accepted */
 234 #define STATE_ADDR_MASK        0x00000070 /* address states mask */
 235
 236 /* During data input/output the simulator is in these states */
 237 #define STATE_DATAIN           0x00000100 /* waiting for data input */
 238 #define STATE_DATAIN_MASK      0x00000100 /* data input states mask */
 239
 240 #define STATE_DATAOUT          0x00001000 /* waiting for page data output */
 241 #define STATE_DATAOUT_ID       0x00002000 /* waiting for ID bytes output */
 242 #define STATE_DATAOUT_STATUS   0x00003000 /* waiting for status output */
 243 #define STATE_DATAOUT_STATUS_M 0x00004000 /* waiting for multi-plane status output */
 244 #define STATE_DATAOUT_MASK     0x00007000 /* data output states mask */
 245
 246 /* Previous operation is done, ready to accept new requests */
 247 #define STATE_READY            0x00000000
 248
 249 /* This state is used to mark that the next state isn't known yet */
 250 #define STATE_UNKNOWN          0x10000000
 251
 252 /* Simulator's actions bit masks */
 253 #define ACTION_CPY       0x00100000 /* copy page/OOB to the internal buffer */
 254 #define ACTION_PRGPAGE   0x00200000 /* program the internal buffer to flash */
 255 #define ACTION_SECERASE  0x00300000 /* erase sector */
 256 #define ACTION_ZEROOFF   0x00400000 /* don't add any offset to address */
 257 #define ACTION_HALFOFF   0x00500000 /* add to address half of page */
 258 #define ACTION_OOBOFF    0x00600000 /* add to address OOB offset */
 259 #define ACTION_MASK      0x00700000 /* action mask */
 260
 261 #define NS_OPER_NUM      13 /* Number of operations supported by the simulator */
 262 #define NS_OPER_STATES   6  /* Maximum number of states in operation */
 263
 264 #define OPT_ANY          0xFFFFFFFF /* any chip supports this operation */
 265 #define OPT_PAGE512      0x00000002 /* 512-byte  page chips */
 266 #define OPT_PAGE2048     0x00000008 /* 2048-byte page chips */
 267 #define OPT_SMARTMEDIA   0x00000010 /* SmartMedia technology chips */
 268 #define OPT_PAGE512_8BIT 0x00000040 /* 512-byte page chips with 8-bit bus width */
 269 #define OPT_PAGE4096     0x00000080 /* 4096-byte page chips */
 270 #define OPT_LARGEPAGE    (OPT_PAGE2048 | OPT_PAGE4096) /* 2048 & 4096-byte page chips */
 271 #define OPT_SMALLPAGE    (OPT_PAGE512) /* 512-byte page chips */
 272
 273 /* Remove action bits from state */
 274 #define NS_STATE(x) ((x) & ~ACTION_MASK)
 275
 276 /*
 277  * Maximum previous states which need to be saved. Currently saving is
 278  * only needed for page program operation with preceded read command
 279  * (which is only valid for 512-byte pages).
 280  */
 281 #define NS_MAX_PREVSTATES 1
 282
 283 /* Maximum page cache pages needed to read or write a NAND page to the cache_file */
 284 #define NS_MAX_HELD_PAGES 16
 285
 286 struct nandsim_debug_info {
 287         struct dentry *dfs_root;
 288         struct dentry *dfs_wear_report;
 289 };
 290
 291 /*
 292  * A union to represent flash memory contents and flash buffer.
 293  */
 294 union ns_mem {
 295         u_char *byte;    /* for byte access */
 296         uint16_t *word;  /* for 16-bit word access */
 297 };
 298
 299 /*
 300  * The structure which describes all the internal simulator data.
 301  */
 302 struct nandsim {
 303         struct mtd_partition partitions[CONFIG_NANDSIM_MAX_PARTS];
 304         unsigned int nbparts;
 305
 306         uint busw;              /* flash chip bus width (8 or 16) */
 307         u_char ids[4];          /* chip's ID bytes */
 308         uint32_t options;       /* chip's characteristic bits */
 309         uint32_t state;         /* current chip state */
 310         uint32_t nxstate;       /* next expected state */
 311
 312         uint32_t *op;           /* current operation, NULL operations isn't known yet  */
 313         uint32_t pstates[NS_MAX_PREVSTATES]; /* previous states */
 314         uint16_t npstates;      /* number of previous states saved */
 315         uint16_t stateidx;      /* current state index */
 316
 317         /* The simulated NAND flash pages array */
 318         union ns_mem *pages;
 319
 320         /* Slab allocator for nand pages */
 321         struct kmem_cache *nand_pages_slab;
 322
 323         /* Internal buffer of page + OOB size bytes */
 324         union ns_mem buf;
 325
 326         /* NAND flash "geometry" */
 327         struct {
 328                 uint64_t totsz;     /* total flash size, bytes */
 329                 uint32_t secsz;     /* flash sector (erase block) size, bytes */
 330                 uint pgsz;          /* NAND flash page size, bytes */
 331                 uint oobsz;         /* page OOB area size, bytes */
 332                 uint64_t totszoob;  /* total flash size including OOB, bytes */
 333                 uint pgszoob;       /* page size including OOB , bytes*/
 334                 uint secszoob;      /* sector size including OOB, bytes */
 335                 uint pgnum;         /* total number of pages */
 336                 uint pgsec;         /* number of pages per sector */
 337                 uint secshift;      /* bits number in sector size */
 338                 uint pgshift;       /* bits number in page size */
 339                 uint oobshift;      /* bits number in OOB size */
 340                 uint pgaddrbytes;   /* bytes per page address */
 341                 uint secaddrbytes;  /* bytes per sector address */
 342                 uint idbytes;       /* the number ID bytes that this chip outputs */
 343         } geom;
 344
 345         /* NAND flash internal registers */
 346         struct {
 347                 unsigned command; /* the command register */
 348                 u_char   status;  /* the status register */
 349                 uint     row;     /* the page number */
 350                 uint     column;  /* the offset within page */
 351                 uint     count;   /* internal counter */
 352                 uint     num;     /* number of bytes which must be processed */
 353                 uint     off;     /* fixed page offset */
 354         } regs;
 355
 356         /* NAND flash lines state */
 357         struct {
 358                 int ce;  /* chip Enable */
 359                 int cle; /* command Latch Enable */
 360                 int ale; /* address Latch Enable */
 361                 int wp;  /* write Protect */
 362         } lines;
 363
 364         /* Fields needed when using a cache file */
 365         struct file *cfile; /* Open file */
 366         unsigned char *pages_written; /* Which pages have been written */
 367         void *file_buf;
 368         struct page *held_pages[NS_MAX_HELD_PAGES];
 369         int held_cnt;
 370
 371         struct nandsim_debug_info dbg;
 372 };
 373
 374 /*
 375  * Operations array. To perform any operation the simulator must pass
 376  * through the correspondent states chain.
 377  */
 378 static struct nandsim_operations {
 379         uint32_t reqopts;  /* options which are required to perform the operation */
 380         uint32_t states[NS_OPER_STATES]; /* operation's states */
 381 } ops[NS_OPER_NUM] = {
 382         /* Read page + OOB from the beginning */
 383         {OPT_SMALLPAGE, {STATE_CMD_READ0 | ACTION_ZEROOFF, STATE_ADDR_PAGE | ACTION_CPY,
 384                         STATE_DATAOUT, STATE_READY}},
 385         /* Read page + OOB from the second half */
 386         {OPT_PAGE512_8BIT, {STATE_CMD_READ1 | ACTION_HALFOFF, STATE_ADDR_PAGE | ACTION_CPY,
 387                         STATE_DATAOUT, STATE_READY}},
 388         /* Read OOB */
 389         {OPT_SMALLPAGE, {STATE_CMD_READOOB | ACTION_OOBOFF, STATE_ADDR_PAGE | ACTION_CPY,
 390                         STATE_DATAOUT, STATE_READY}},
 391         /* Program page starting from the beginning */
 392         {OPT_ANY, {STATE_CMD_SEQIN, STATE_ADDR_PAGE, STATE_DATAIN,
 393                         STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},
 394         /* Program page starting from the beginning */
 395         {OPT_SMALLPAGE, {STATE_CMD_READ0, STATE_CMD_SEQIN | ACTION_ZEROOFF, STATE_ADDR_PAGE,
 396                               STATE_DATAIN, STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},
 397         /* Program page starting from the second half */
 398         {OPT_PAGE512, {STATE_CMD_READ1, STATE_CMD_SEQIN | ACTION_HALFOFF, STATE_ADDR_PAGE,
 399                               STATE_DATAIN, STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},
 400         /* Program OOB */
 401         {OPT_SMALLPAGE, {STATE_CMD_READOOB, STATE_CMD_SEQIN | ACTION_OOBOFF, STATE_ADDR_PAGE,
 402                               STATE_DATAIN, STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},
 403         /* Erase sector */
 404         {OPT_ANY, {STATE_CMD_ERASE1, STATE_ADDR_SEC, STATE_CMD_ERASE2 | ACTION_SECERASE, STATE_READY}},
 405         /* Read status */
 406         {OPT_ANY, {STATE_CMD_STATUS, STATE_DATAOUT_STATUS, STATE_READY}},
 407         /* Read ID */
 408         {OPT_ANY, {STATE_CMD_READID, STATE_ADDR_ZERO, STATE_DATAOUT_ID, STATE_READY}},
 409         /* Large page devices read page */
 410         {OPT_LARGEPAGE, {STATE_CMD_READ0, STATE_ADDR_PAGE, STATE_CMD_READSTART | ACTION_CPY,
 411                                STATE_DATAOUT, STATE_READY}},
 412         /* Large page devices random page read */
 413         {OPT_LARGEPAGE, {STATE_CMD_RNDOUT, STATE_ADDR_COLUMN, STATE_CMD_RNDOUTSTART | ACTION_CPY,
 414                                STATE_DATAOUT, STATE_READY}},
 415 };
 416
 417 struct weak_block {
 418         struct list_head list;
 419         unsigned int erase_block_no;
 420         unsigned int max_erases;
 421         unsigned int erases_done;
 422 };
 423
 424 static LIST_HEAD(weak_blocks);
 425
 426 struct weak_page {
 427         struct list_head list;
 428         unsigned int page_no;
 429         unsigned int max_writes;
 430         unsigned int writes_done;
 431 };
 432
 433 static LIST_HEAD(weak_pages);
 434
 435 struct grave_page {
 436         struct list_head list;
 437         unsigned int page_no;
 438         unsigned int max_reads;
 439         unsigned int reads_done;
 440 };
 441
 442 static LIST_HEAD(grave_pages);
 443
 444 static unsigned long *erase_block_wear = NULL;
 445 static unsigned int wear_eb_count = 0;
 446 static unsigned long total_wear = 0;
 447
 448 /* MTD structure for NAND controller */
 449 static struct mtd_info *nsmtd;
 450
 451 static int nandsim_debugfs_show(struct seq_file *m, void *private)
 452 {
 453         unsigned long wmin = -1, wmax = 0, avg;
 454         unsigned long deciles[10], decile_max[10], tot = 0;
 455         unsigned int i;
 456
 457         /* Calc wear stats */
 458         for (i = 0; i < wear_eb_count; ++i) {
 459                 unsigned long wear = erase_block_wear[i];
 460                 if (wear < wmin)
 461                         wmin = wear;
 462                 if (wear > wmax)
 463                         wmax = wear;
 464                 tot += wear;
 465         }
 466
 467         for (i = 0; i < 9; ++i) {
 468                 deciles[i] = 0;
 469                 decile_max[i] = (wmax * (i + 1) + 5) / 10;
 470         }
 471         deciles[9] = 0;
 472         decile_max[9] = wmax;
 473         for (i = 0; i < wear_eb_count; ++i) {
 474                 int d;
 475                 unsigned long wear = erase_block_wear[i];
 476                 for (d = 0; d < 10; ++d)
 477                         if (wear <= decile_max[d]) {
 478                                 deciles[d] += 1;
 479                                 break;
 480                         }
 481         }
 482         avg = tot / wear_eb_count;
 483
 484         /* Output wear report */
 485         seq_printf(m, "Total numbers of erases:  %lu\n", tot);
 486         seq_printf(m, "Number of erase blocks:   %u\n", wear_eb_count);
 487         seq_printf(m, "Average number of erases: %lu\n", avg);
 488         seq_printf(m, "Maximum number of erases: %lu\n", wmax);
 489         seq_printf(m, "Minimum number of erases: %lu\n", wmin);
 490         for (i = 0; i < 10; ++i) {
 491                 unsigned long from = (i ? decile_max[i - 1] + 1 : 0);
 492                 if (from > decile_max[i])
 493                         continue;
 494                 seq_printf(m, "Number of ebs with erase counts from %lu to %lu : %lu\n",
 495                         from,
 496                         decile_max[i],
 497                         deciles[i]);
 498         }
 499
 500         return 0;
 501 }
 502
 503 static int nandsim_debugfs_open(struct inode *inode, struct file *file)
 504 {
 505         return single_open(file, nandsim_debugfs_show, inode->i_private);
 506 }
 507
 508 static const struct file_operations dfs_fops = {
 509         .open           = nandsim_debugfs_open,
 510         .read           = seq_read,
 511         .llseek         = seq_lseek,
 512         .release        = single_release,
 513 };
 514
 515 /**
 516  * nandsim_debugfs_create - initialize debugfs
 517  * @dev: nandsim device description object
 518  *
 519  * This function creates all debugfs files for UBI device @ubi. Returns zero in
 520  * case of success and a negative error code in case of failure.
 521  */
 522 static int nandsim_debugfs_create(struct nandsim *dev)
 523 {
 524         struct nandsim_debug_info *dbg = &dev->dbg;
 525         struct dentry *dent;
 526         int err;
 527
 528         if (!IS_ENABLED(CONFIG_DEBUG_FS))
 529                 return 0;
 530
 531         dent = debugfs_create_dir("nandsim", NULL);
 532         if (IS_ERR_OR_NULL(dent)) {
 533                 int err = dent ? -ENODEV : PTR_ERR(dent);
 534
 535                 NS_ERR("cannot create \"nandsim\" debugfs directory, err %d\n",
 536                         err);
 537                 return err;
 538         }
 539         dbg->dfs_root = dent;
 540
 541         dent = debugfs_create_file("wear_report", S_IRUSR,
 542                                    dbg->dfs_root, dev, &dfs_fops);
 543         if (IS_ERR_OR_NULL(dent))
 544                 goto out_remove;
 545         dbg->dfs_wear_report = dent;
 546
 547         return 0;
 548
 549 out_remove:
 550         debugfs_remove_recursive(dbg->dfs_root);
 551         err = dent ? PTR_ERR(dent) : -ENODEV;
 552         return err;
 553 }
 554
 555 /**
 556  * nandsim_debugfs_remove - destroy all debugfs files
 557  */
 558 static void nandsim_debugfs_remove(struct nandsim *ns)
 559 {
 560         if (IS_ENABLED(CONFIG_DEBUG_FS))
 561                 debugfs_remove_recursive(ns->dbg.dfs_root);
 562 }
 563
 564 /*
 565  * Allocate array of page pointers, create slab allocation for an array
 566  * and initialize the array by NULL pointers.
 567  *
 568  * RETURNS: 0 if success, -ENOMEM if memory alloc fails.
 569  */
 570 static int alloc_device(struct nandsim *ns)
 571 {
 572         struct file *cfile;
 573         int i, err;
 574
 575         if (cache_file) {
 576                 cfile = filp_open(cache_file, O_CREAT | O_RDWR | O_LARGEFILE, 0600);
 577                 if (IS_ERR(cfile))
 578                         return PTR_ERR(cfile);
 579                 if (!cfile->f_op || (!cfile->f_op->read && !cfile->f_op->aio_read)) {
 580                         NS_ERR("alloc_device: cache file not readable\n");
 581                         err = -EINVAL;
 582                         goto err_close;
 583                 }
 584                 if (!cfile->f_op->write && !cfile->f_op->aio_write) {
 585                         NS_ERR("alloc_device: cache file not writeable\n");
 586                         err = -EINVAL;
 587                         goto err_close;
 588                 }
 589                 ns->pages_written = vzalloc(ns->geom.pgnum);
 590                 if (!ns->pages_written) {
 591                         NS_ERR("alloc_device: unable to allocate pages written array\n");
 592                         err = -ENOMEM;
 593                         goto err_close;
 594                 }
 595                 ns->file_buf = kmalloc(ns->geom.pgszoob, GFP_KERNEL);
 596                 if (!ns->file_buf) {
 597                         NS_ERR("alloc_device: unable to allocate file buf\n");
 598                         err = -ENOMEM;
 599                         goto err_free;
 600                 }
 601                 ns->cfile = cfile;
 602                 return 0;
 603         }
 604
 605         ns->pages = vmalloc(ns->geom.pgnum * sizeof(union ns_mem));
 606         if (!ns->pages) {
 607                 NS_ERR("alloc_device: unable to allocate page array\n");
 608                 return -ENOMEM;
 609         }
 610         for (i = 0; i < ns->geom.pgnum; i++) {
 611                 ns->pages[i].byte = NULL;
 612         }
 613         ns->nand_pages_slab = kmem_cache_create("nandsim",
 614                                                 ns->geom.pgszoob, 0, 0, NULL);
 615         if (!ns->nand_pages_slab) {
 616                 NS_ERR("cache_create: unable to create kmem_cache\n");
 617                 return -ENOMEM;
 618         }
 619
 620         return 0;
 621
 622 err_free:
 623         vfree(ns->pages_written);
 624 err_close:
 625         filp_close(cfile, NULL);
 626         return err;
 627 }
 628
 629 /*
 630  * Free any allocated pages, and free the array of page pointers.
 631  */
 632 static void free_device(struct nandsim *ns)
 633 {
 634         int i;
 635
 636         if (ns->cfile) {
 637                 kfree(ns->file_buf);
 638                 vfree(ns->pages_written);
 639                 filp_close(ns->cfile, NULL);
 640                 return;
 641         }
 642
 643         if (ns->pages) {
 644                 for (i = 0; i < ns->geom.pgnum; i++) {
 645                         if (ns->pages[i].byte)
 646                                 kmem_cache_free(ns->nand_pages_slab,
 647                                                 ns->pages[i].byte);
 648                 }
 649                 kmem_cache_destroy(ns->nand_pages_slab);
 650                 vfree(ns->pages);
 651         }
 652 }
 653
 654 static char *get_partition_name(int i)
 655 {
 656         char buf[64];
 657         sprintf(buf, "NAND simulator partition %d", i);
 658         return kstrdup(buf, GFP_KERNEL);
 659 }
 660
 661 /*
 662  * Initialize the nandsim structure.
 663  *
 664  * RETURNS: 0 if success, -ERRNO if failure.
 665  */
 666 static int init_nandsim(struct mtd_info *mtd)
 667 {
 668         struct nand_chip *chip = mtd->priv;
 669         struct nandsim   *ns   = chip->priv;
 670         int i, ret = 0;
 671         uint64_t remains;
 672         uint64_t next_offset;
 673
 674         if (NS_IS_INITIALIZED(ns)) {
 675                 NS_ERR("init_nandsim: nandsim is already initialized\n");
 676                 return -EIO;
 677         }
 678
 679         /* Force mtd to not do delays */
 680         chip->chip_delay = 0;
 681
 682         /* Initialize the NAND flash parameters */
 683         ns->busw = chip->options & NAND_BUSWIDTH_16 ? 16 : 8;
 684         ns->geom.totsz    = mtd->size;
 685         ns->geom.pgsz     = mtd->writesize;
 686         ns->geom.oobsz    = mtd->oobsize;
 687         ns->geom.secsz    = mtd->erasesize;
 688         ns->geom.pgszoob  = ns->geom.pgsz + ns->geom.oobsz;
 689         ns->geom.pgnum    = div_u64(ns->geom.totsz, ns->geom.pgsz);
 690         ns->geom.totszoob = ns->geom.totsz + (uint64_t)ns->geom.pgnum * ns->geom.oobsz;
 691         ns->geom.secshift = ffs(ns->geom.secsz) - 1;
 692         ns->geom.pgshift  = chip->page_shift;
 693         ns->geom.oobshift = ffs(ns->geom.oobsz) - 1;
 694         ns->geom.pgsec    = ns->geom.secsz / ns->geom.pgsz;
 695         ns->geom.secszoob = ns->geom.secsz + ns->geom.oobsz * ns->geom.pgsec;
 696         ns->options = 0;
 697
 698         if (ns->geom.pgsz == 512) {
 699                 ns->options |= OPT_PAGE512;
 700                 if (ns->busw == 8)
 701                         ns->options |= OPT_PAGE512_8BIT;
 702         } else if (ns->geom.pgsz == 2048) {
 703                 ns->options |= OPT_PAGE2048;
 704         } else if (ns->geom.pgsz == 4096) {
 705                 ns->options |= OPT_PAGE4096;
 706         } else {
 707                 NS_ERR("init_nandsim: unknown page size %u\n", ns->geom.pgsz);
 708                 return -EIO;
 709         }
 710
 711         if (ns->options & OPT_SMALLPAGE) {
 712                 if (ns->geom.totsz <= (32 << 20)) {
 713                         ns->geom.pgaddrbytes  = 3;
 714                         ns->geom.secaddrbytes = 2;
 715                 } else {
 716                         ns->geom.pgaddrbytes  = 4;
 717                         ns->geom.secaddrbytes = 3;
 718                 }
 719         } else {
 720                 if (ns->geom.totsz <= (128 << 20)) {
 721                         ns->geom.pgaddrbytes  = 4;
 722                         ns->geom.secaddrbytes = 2;
 723                 } else {
 724                         ns->geom.pgaddrbytes  = 5;
 725                         ns->geom.secaddrbytes = 3;
 726                 }
 727         }
 728
 729         /* Fill the partition_info structure */
 730         if (parts_num > ARRAY_SIZE(ns->partitions)) {
 731                 NS_ERR("too many partitions.\n");
 732                 ret = -EINVAL;
 733                 goto error;
 734         }
 735         remains = ns->geom.totsz;
 736         next_offset = 0;
 737         for (i = 0; i < parts_num; ++i) {
 738                 uint64_t part_sz = (uint64_t)parts[i] * ns->geom.secsz;
 739
 740                 if (!part_sz || part_sz > remains) {
 741                         NS_ERR("bad partition size.\n");
 742                         ret = -EINVAL;
 743                         goto error;
 744                 }
 745                 ns->partitions[i].name   = get_partition_name(i);
 746                 ns->partitions[i].offset = next_offset;
 747                 ns->partitions[i].size   = part_sz;
 748                 next_offset += ns->partitions[i].size;
 749                 remains -= ns->partitions[i].size;
 750         }
 751         ns->nbparts = parts_num;
 752         if (remains) {
 753                 if (parts_num + 1 > ARRAY_SIZE(ns->partitions)) {
 754                         NS_ERR("too many partitions.\n");
 755                         ret = -EINVAL;
 756                         goto error;
 757                 }
 758                 ns->partitions[i].name   = get_partition_name(i);
 759                 ns->partitions[i].offset = next_offset;
 760                 ns->partitions[i].size   = remains;
 761                 ns->nbparts += 1;
 762         }
 763
 764         /* Detect how many ID bytes the NAND chip outputs */
 765         for (i = 0; nand_flash_ids[i].name != NULL; i++) {
 766                 if (second_id_byte != nand_flash_ids[i].dev_id)
 767                         continue;
 768         }
 769
 770         if (ns->busw == 16)
 771                 NS_WARN("16-bit flashes support wasn't tested\n");
 772
 773         printk("flash size: %llu MiB\n",
 774                         (unsigned long long)ns->geom.totsz >> 20);
 775         printk("page size: %u bytes\n",         ns->geom.pgsz);
 776         printk("OOB area size: %u bytes\n",     ns->geom.oobsz);
 777         printk("sector size: %u KiB\n",         ns->geom.secsz >> 10);
 778         printk("pages number: %u\n",            ns->geom.pgnum);
 779         printk("pages per sector: %u\n",        ns->geom.pgsec);
 780         printk("bus width: %u\n",               ns->busw);
 781         printk("bits in sector size: %u\n",     ns->geom.secshift);
 782         printk("bits in page size: %u\n",       ns->geom.pgshift);
 783         printk("bits in OOB size: %u\n",        ns->geom.oobshift);
 784         printk("flash size with OOB: %llu KiB\n",
 785                         (unsigned long long)ns->geom.totszoob >> 10);
 786         printk("page address bytes: %u\n",      ns->geom.pgaddrbytes);
 787         printk("sector address bytes: %u\n",    ns->geom.secaddrbytes);
 788         printk("options: %#x\n",                ns->options);
 789
 790         if ((ret = alloc_device(ns)) != 0)
 791                 goto error;
 792
 793         /* Allocate / initialize the internal buffer */
 794         ns->buf.byte = kmalloc(ns->geom.pgszoob, GFP_KERNEL);
 795         if (!ns->buf.byte) {
 796                 NS_ERR("init_nandsim: unable to allocate %u bytes for the internal buffer\n",
 797                         ns->geom.pgszoob);
 798                 ret = -ENOMEM;
 799                 goto error;
 800         }
 801         memset(ns->buf.byte, 0xFF, ns->geom.pgszoob);
 802
 803         return 0;
 804
 805 error:
 806         free_device(ns);
 807
 808         return ret;
 809 }
 810
 811 /*
 812  * Free the nandsim structure.
 813  */
 814 static void free_nandsim(struct nandsim *ns)
 815 {
 816         kfree(ns->buf.byte);
 817         free_device(ns);
 818
 819         return;
 820 }
 821
 822 static int parse_badblocks(struct nandsim *ns, struct mtd_info *mtd)
 823 {
 824         char *w;
 825         int zero_ok;
 826         unsigned int erase_block_no;
 827         loff_t offset;
 828
 829         if (!badblocks)
 830                 return 0;
 831         w = badblocks;
 832         do {
 833                 zero_ok = (*w == '0' ? 1 : 0);
 834                 erase_block_no = simple_strtoul(w, &w, 0);
 835                 if (!zero_ok && !erase_block_no) {
 836                         NS_ERR("invalid badblocks.\n");
 837                         return -EINVAL;
 838                 }
 839                 offset = erase_block_no * ns->geom.secsz;
 840                 if (mtd_block_markbad(mtd, offset)) {
 841                         NS_ERR("invalid badblocks.\n");
 842                         return -EINVAL;
 843                 }
 844                 if (*w == ',')
 845                         w += 1;
 846         } while (*w);
 847         return 0;
 848 }
 849
 850 static int parse_weakblocks(void)
 851 {
 852         char *w;
 853         int zero_ok;
 854         unsigned int erase_block_no;
 855         unsigned int max_erases;
 856         struct weak_block *wb;
 857
 858         if (!weakblocks)
 859                 return 0;
 860         w = weakblocks;
 861         do {
 862                 zero_ok = (*w == '0' ? 1 : 0);
 863                 erase_block_no = simple_strtoul(w, &w, 0);
 864                 if (!zero_ok && !erase_block_no) {
 865                         NS_ERR("invalid weakblocks.\n");
 866                         return -EINVAL;
 867                 }
 868                 max_erases = 3;
 869                 if (*w == ':') {
 870                         w += 1;
 871                         max_erases = simple_strtoul(w, &w, 0);
 872                 }
 873                 if (*w == ',')
 874                         w += 1;
 875                 wb = kzalloc(sizeof(*wb), GFP_KERNEL);
 876                 if (!wb) {
 877                         NS_ERR("unable to allocate memory.\n");
 878                         return -ENOMEM;
 879                 }
 880                 wb->erase_block_no = erase_block_no;
 881                 wb->max_erases = max_erases;
 882                 list_add(&wb->list, &weak_blocks);
 883         } while (*w);
 884         return 0;
 885 }
 886
 887 static int erase_error(unsigned int erase_block_no)
 888 {
 889         struct weak_block *wb;
 890
 891         list_for_each_entry(wb, &weak_blocks, list)
 892                 if (wb->erase_block_no == erase_block_no) {
 893                         if (wb->erases_done >= wb->max_erases)
 894                                 return 1;
 895                         wb->erases_done += 1;
 896                         return 0;
 897                 }
 898         return 0;
 899 }
 900
 901 static int parse_weakpages(void)
 902 {
 903         char *w;
 904         int zero_ok;
 905         unsigned int page_no;
 906         unsigned int max_writes;
 907         struct weak_page *wp;
 908
 909         if (!weakpages)
 910                 return 0;
 911         w = weakpages;
 912         do {
 913                 zero_ok = (*w == '0' ? 1 : 0);
 914                 page_no = simple_strtoul(w, &w, 0);
 915                 if (!zero_ok && !page_no) {
 916                         NS_ERR("invalid weakpagess.\n");
 917                         return -EINVAL;
 918                 }
 919                 max_writes = 3;
 920                 if (*w == ':') {
 921                         w += 1;
 922                         max_writes = simple_strtoul(w, &w, 0);
 923                 }
 924                 if (*w == ',')
 925                         w += 1;
 926                 wp = kzalloc(sizeof(*wp), GFP_KERNEL);
 927                 if (!wp) {
 928                         NS_ERR("unable to allocate memory.\n");
 929                         return -ENOMEM;
 930                 }
 931                 wp->page_no = page_no;
 932                 wp->max_writes = max_writes;
 933                 list_add(&wp->list, &weak_pages);
 934         } while (*w);
 935         return 0;
 936 }
 937
 938 static int write_error(unsigned int page_no)
 939 {
 940         struct weak_page *wp;
 941
 942         list_for_each_entry(wp, &weak_pages, list)
 943                 if (wp->page_no == page_no) {
 944                         if (wp->writes_done >= wp->max_writes)
 945                                 return 1;
 946                         wp->writes_done += 1;
 947                         return 0;
 948                 }
 949         return 0;
 950 }
 951
 952 static int parse_gravepages(void)
 953 {
 954         char *g;
 955         int zero_ok;
 956         unsigned int page_no;
 957         unsigned int max_reads;
 958         struct grave_page *gp;
 959
 960         if (!gravepages)
 961                 return 0;
 962         g = gravepages;
 963         do {
 964                 zero_ok = (*g == '0' ? 1 : 0);
 965                 page_no = simple_strtoul(g, &g, 0);
 966                 if (!zero_ok && !page_no) {
 967                         NS_ERR("invalid gravepagess.\n");
 968                         return -EINVAL;
 969                 }
 970                 max_reads = 3;
 971                 if (*g == ':') {
 972                         g += 1;
 973                         max_reads = simple_strtoul(g, &g, 0);
 974                 }
 975                 if (*g == ',')
 976                         g += 1;
 977                 gp = kzalloc(sizeof(*gp), GFP_KERNEL);
 978                 if (!gp) {
 979                         NS_ERR("unable to allocate memory.\n");
 980                         return -ENOMEM;
 981                 }
 982                 gp->page_no = page_no;
 983                 gp->max_reads = max_reads;
 984                 list_add(&gp->list, &grave_pages);
 985         } while (*g);
 986         return 0;
 987 }
 988
 989 static int read_error(unsigned int page_no)
 990 {
 991         struct grave_page *gp;
 992
 993         list_for_each_entry(gp, &grave_pages, list)
 994                 if (gp->page_no == page_no) {
 995                         if (gp->reads_done >= gp->max_reads)
 996                                 return 1;
 997                         gp->reads_done += 1;
 998                         return 0;
 999                 }
1000         return 0;
1001 }
1002
1003 static void free_lists(void)
1004 {
1005         struct list_head *pos, *n;
1006         list_for_each_safe(pos, n, &weak_blocks) {
1007                 list_del(pos);
1008                 kfree(list_entry(pos, struct weak_block, list));
1009         }
1010         list_for_each_safe(pos, n, &weak_pages) {
1011                 list_del(pos);
1012                 kfree(list_entry(pos, struct weak_page, list));
1013         }
1014         list_for_each_safe(pos, n, &grave_pages) {
1015                 list_del(pos);
1016                 kfree(list_entry(pos, struct grave_page, list));
1017         }
1018         kfree(erase_block_wear);
1019 }
1020
1021 static int setup_wear_reporting(struct mtd_info *mtd)
1022 {
1023         size_t mem;
1024
1025         wear_eb_count = div_u64(mtd->size, mtd->erasesize);
1026         mem = wear_eb_count * sizeof(unsigned long);
1027         if (mem / sizeof(unsigned long) != wear_eb_count) {
1028                 NS_ERR("Too many erase blocks for wear reporting\n");
1029                 return -ENOMEM;
1030         }
1031         erase_block_wear = kzalloc(mem, GFP_KERNEL);
1032         if (!erase_block_wear) {
1033                 NS_ERR("Too many erase blocks for wear reporting\n");
1034                 return -ENOMEM;
1035         }
1036         return 0;
1037 }
1038
1039 static void update_wear(unsigned int erase_block_no)
1040 {
1041         if (!erase_block_wear)
1042                 return;
1043         total_wear += 1;
1044         /*
1045          * TODO: Notify this through a debugfs entry,
1046          * instead of showing an error message.
1047          */
1048         if (total_wear == 0)
1049                 NS_ERR("Erase counter total overflow\n");
1050         erase_block_wear[erase_block_no] += 1;
1051         if (erase_block_wear[erase_block_no] == 0)
1052                 NS_ERR("Erase counter overflow for erase block %u\n", erase_block_no);
1053 }
1054
1055 /*
1056  * Returns the string representation of 'state' state.
1057  */
1058 static char *get_state_name(uint32_t state)
1059 {
1060         switch (NS_STATE(state)) {
1061                 case STATE_CMD_READ0:
1062                         return "STATE_CMD_READ0";
1063                 case STATE_CMD_READ1:
1064                         return "STATE_CMD_READ1";
1065                 case STATE_CMD_PAGEPROG:
1066                         return "STATE_CMD_PAGEPROG";
1067                 case STATE_CMD_READOOB:
1068                         return "STATE_CMD_READOOB";
1069                 case STATE_CMD_READSTART:
1070                         return "STATE_CMD_READSTART";
1071                 case STATE_CMD_ERASE1:
1072                         return "STATE_CMD_ERASE1";
1073                 case STATE_CMD_STATUS:
1074                         return "STATE_CMD_STATUS";
1075                 case STATE_CMD_SEQIN:
1076                         return "STATE_CMD_SEQIN";
1077                 case STATE_CMD_READID:
1078                         return "STATE_CMD_READID";
1079                 case STATE_CMD_ERASE2:
1080                         return "STATE_CMD_ERASE2";
1081                 case STATE_CMD_RESET:
1082                         return "STATE_CMD_RESET";
1083                 case STATE_CMD_RNDOUT:
1084                         return "STATE_CMD_RNDOUT";
1085                 case STATE_CMD_RNDOUTSTART:
1086                         return "STATE_CMD_RNDOUTSTART";
1087                 case STATE_ADDR_PAGE:
1088                         return "STATE_ADDR_PAGE";
1089                 case STATE_ADDR_SEC:
1090                         return "STATE_ADDR_SEC";
1091                 case STATE_ADDR_ZERO:
1092                         return "STATE_ADDR_ZERO";
1093                 case STATE_ADDR_COLUMN:
1094                         return "STATE_ADDR_COLUMN";
1095                 case STATE_DATAIN:
1096                         return "STATE_DATAIN";
1097                 case STATE_DATAOUT:
1098                         return "STATE_DATAOUT";
1099                 case STATE_DATAOUT_ID:
1100                         return "STATE_DATAOUT_ID";
1101                 case STATE_DATAOUT_STATUS:
1102                         return "STATE_DATAOUT_STATUS";
1103                 case STATE_DATAOUT_STATUS_M:
1104                         return "STATE_DATAOUT_STATUS_M";
1105                 case STATE_READY:
1106                         return "STATE_READY";
1107                 case STATE_UNKNOWN:
1108                         return "STATE_UNKNOWN";
1109         }
1110
1111         NS_ERR("get_state_name: unknown state, BUG\n");
1112         return NULL;
1113 }
1114
1115 /*
1116  * Check if command is valid.
1117  *
1118  * RETURNS: 1 if wrong command, 0 if right.
1119  */
1120 static int check_command(int cmd)
1121 {
1122         switch (cmd) {
1123
1124         case NAND_CMD_READ0:
1125         case NAND_CMD_READ1:
1126         case NAND_CMD_READSTART:
1127         case NAND_CMD_PAGEPROG:
1128         case NAND_CMD_READOOB:
1129         case NAND_CMD_ERASE1:
1130         case NAND_CMD_STATUS:
1131         case NAND_CMD_SEQIN:
1132         case NAND_CMD_READID:
1133         case NAND_CMD_ERASE2:
1134         case NAND_CMD_RESET:
1135         case NAND_CMD_RNDOUT:
1136         case NAND_CMD_RNDOUTSTART:
1137                 return 0;
1138
1139         default:
1140                 return 1;
1141         }
1142 }
1143
1144 /*
1145  * Returns state after command is accepted by command number.
1146  */
1147 static uint32_t get_state_by_command(unsigned command)
1148 {
1149         switch (command) {
1150                 case NAND_CMD_READ0:
1151                         return STATE_CMD_READ0;
1152                 case NAND_CMD_READ1:
1153                         return STATE_CMD_READ1;
1154                 case NAND_CMD_PAGEPROG:
1155                         return STATE_CMD_PAGEPROG;
1156                 case NAND_CMD_READSTART:
1157                         return STATE_CMD_READSTART;
1158                 case NAND_CMD_READOOB:
1159                         return STATE_CMD_READOOB;
1160                 case NAND_CMD_ERASE1:
1161                         return STATE_CMD_ERASE1;
1162                 case NAND_CMD_STATUS:
1163                         return STATE_CMD_STATUS;
1164                 case NAND_CMD_SEQIN:
1165                         return STATE_CMD_SEQIN;
1166                 case NAND_CMD_READID:
1167                         return STATE_CMD_READID;
1168                 case NAND_CMD_ERASE2:
1169                         return STATE_CMD_ERASE2;
1170                 case NAND_CMD_RESET:
1171                         return STATE_CMD_RESET;
1172                 case NAND_CMD_RNDOUT:
1173                         return STATE_CMD_RNDOUT;
1174                 case NAND_CMD_RNDOUTSTART:
1175                         return STATE_CMD_RNDOUTSTART;
1176         }
1177
1178         NS_ERR("get_state_by_command: unknown command, BUG\n");
1179         return 0;
1180 }
1181
1182 /*
1183  * Move an address byte to the correspondent internal register.
1184  */
1185 static inline void accept_addr_byte(struct nandsim *ns, u_char bt)
1186 {
1187         uint byte = (uint)bt;
1188
1189         if (ns->regs.count < (ns->geom.pgaddrbytes - ns->geom.secaddrbytes))
1190                 ns->regs.column |= (byte << 8 * ns->regs.count);
1191         else {
1192                 ns->regs.row |= (byte << 8 * (ns->regs.count -
1193                                                 ns->geom.pgaddrbytes +
1194                                                 ns->geom.secaddrbytes));
1195         }
1196
1197         return;
1198 }
1199
1200 /*
1201  * Switch to STATE_READY state.
1202  */
1203 static inline void switch_to_ready_state(struct nandsim *ns, u_char status)
1204 {
1205         NS_DBG("switch_to_ready_state: switch to %s state\n", get_state_name(STATE_READY));
1206
1207         ns->state       = STATE_READY;
1208         ns->nxstate     = STATE_UNKNOWN;
1209         ns->op          = NULL;
1210         ns->npstates    = 0;
1211         ns->stateidx    = 0;
1212         ns->regs.num    = 0;
1213         ns->regs.count  = 0;
1214         ns->regs.off    = 0;
1215         ns->regs.row    = 0;
1216         ns->regs.column = 0;
1217         ns->regs.status = status;
1218 }
1219
1220 /*
1221  * If the operation isn't known yet, try to find it in the global array
1222  * of supported operations.
1223  *
1224  * Operation can be unknown because of the following.
1225  *   1. New command was accepted and this is the first call to find the
1226  *      correspondent states chain. In this case ns->npstates = 0;
1227  *   2. There are several operations which begin with the same command(s)
1228  *      (for example program from the second half and read from the
1229  *      second half operations both begin with the READ1 command). In this
1230  *      case the ns->pstates[] array contains previous states.
1231  *
1232  * Thus, the function tries to find operation containing the following
1233  * states (if the 'flag' parameter is 0):
1234  *    ns->pstates[0], ... ns->pstates[ns->npstates], ns->state
1235  *
1236  * If (one and only one) matching operation is found, it is accepted (
1237  * ns->ops, ns->state, ns->nxstate are initialized, ns->npstate is
1238  * zeroed).
1239  *
1240  * If there are several matches, the current state is pushed to the
1241  * ns->pstates.
1242  *
1243  * The operation can be unknown only while commands are input to the chip.
1244  * As soon as address command is accepted, the operation must be known.
1245  * In such situation the function is called with 'flag' != 0, and the
1246  * operation is searched using the following pattern:
1247  *     ns->pstates[0], ... ns->pstates[ns->npstates], <address input>
1248  *
1249  * It is supposed that this pattern must either match one operation or
1250  * none. There can't be ambiguity in that case.
1251  *
1252  * If no matches found, the function does the following:
1253  *   1. if there are saved states present, try to ignore them and search
1254  *      again only using the last command. If nothing was found, switch
1255  *      to the STATE_READY state.
1256  *   2. if there are no saved states, switch to the STATE_READY state.
1257  *
1258  * RETURNS: -2 - no matched operations found.
1259  *          -1 - several matches.
1260  *           0 - operation is found.
1261  */
1262 static int find_operation(struct nandsim *ns, uint32_t flag)
1263 {
1264         int opsfound = 0;
1265         int i, j, idx = 0;
1266
1267         for (i = 0; i < NS_OPER_NUM; i++) {
1268
1269                 int found = 1;
1270
1271                 if (!(ns->options & ops[i].reqopts))
1272                         /* Ignore operations we can't perform */
1273                         continue;
1274
1275                 if (flag) {
1276                         if (!(ops[i].states[ns->npstates] & STATE_ADDR_MASK))
1277                                 continue;
1278                 } else {
1279                         if (NS_STATE(ns->state) != NS_STATE(ops[i].states[ns->npstates]))
1280                                 continue;
1281                 }
1282
1283                 for (j = 0; j < ns->npstates; j++)
1284                         if (NS_STATE(ops[i].states[j]) != NS_STATE(ns->pstates[j])
1285                                 && (ns->options & ops[idx].reqopts)) {
1286                                 found = 0;
1287                                 break;
1288                         }
1289
1290                 if (found) {
1291                         idx = i;
1292                         opsfound += 1;
1293                 }
1294         }
1295
1296         if (opsfound == 1) {
1297                 /* Exact match */
1298                 ns->op = &ops[idx].states[0];
1299                 if (flag) {
1300                         /*
1301                          * In this case the find_operation function was
1302                          * called when address has just began input. But it isn't
1303                          * yet fully input and the current state must
1304                          * not be one of STATE_ADDR_*, but the STATE_ADDR_*
1305                          * state must be the next state (ns->nxstate).
1306                          */
1307                         ns->stateidx = ns->npstates - 1;
1308                 } else {
1309                         ns->stateidx = ns->npstates;
1310                 }
1311                 ns->npstates = 0;
1312                 ns->state = ns->op[ns->stateidx];
1313                 ns->nxstate = ns->op[ns->stateidx + 1];
1314                 NS_DBG("find_operation: operation found, index: %d, state: %s, nxstate %s\n",
1315                                 idx, get_state_name(ns->state), get_state_name(ns->nxstate));
1316                 return 0;
1317         }
1318
1319         if (opsfound == 0) {
1320                 /* Nothing was found. Try to ignore previous commands (if any) and search again */
1321                 if (ns->npstates != 0) {
1322                         NS_DBG("find_operation: no operation found, try again with state %s\n",
1323                                         get_state_name(ns->state));
1324                         ns->npstates = 0;
1325                         return find_operation(ns, 0);
1326
1327                 }
1328                 NS_DBG("find_operation: no operations found\n");
1329                 switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1330                 return -2;
1331         }
1332
1333         if (flag) {
1334                 /* This shouldn't happen */
1335                 NS_DBG("find_operation: BUG, operation must be known if address is input\n");
1336                 return -2;
1337         }
1338
1339         NS_DBG("find_operation: there is still ambiguity\n");
1340
1341         ns->pstates[ns->npstates++] = ns->state;
1342
1343         return -1;
1344 }
1345
1346 static void put_pages(struct nandsim *ns)
1347 {
1348         int i;
1349
1350         for (i = 0; i < ns->held_cnt; i++)
1351                 page_cache_release(ns->held_pages[i]);
1352 }
1353
1354 /* Get page cache pages in advance to provide NOFS memory allocation */
1355 static int get_pages(struct nandsim *ns, struct file *file, size_t count, loff_t pos)
1356 {
1357         pgoff_t index, start_index, end_index;
1358         struct page *page;
1359         struct address_space *mapping = file->f_mapping;
1360
1361         start_index = pos >> PAGE_CACHE_SHIFT;
1362         end_index = (pos + count - 1) >> PAGE_CACHE_SHIFT;
1363         if (end_index - start_index + 1 > NS_MAX_HELD_PAGES)
1364                 return -EINVAL;
1365         ns->held_cnt = 0;
1366         for (index = start_index; index <= end_index; index++) {
1367                 page = find_get_page(mapping, index);
1368                 if (page == NULL) {
1369                         page = find_or_create_page(mapping, index, GFP_NOFS);
1370                         if (page == NULL) {
1371                                 write_inode_now(mapping->host, 1);
1372                                 page = find_or_create_page(mapping, index, GFP_NOFS);
1373                         }
1374                         if (page == NULL) {
1375                                 put_pages(ns);
1376                                 return -ENOMEM;
1377                         }
1378                         unlock_page(page);
1379                 }
1380                 ns->held_pages[ns->held_cnt++] = page;
1381         }
1382         return 0;
1383 }
1384
1385 static int set_memalloc(void)
1386 {
1387         if (current->flags & PF_MEMALLOC)
1388                 return 0;
1389         current->flags |= PF_MEMALLOC;
1390         return 1;
1391 }
1392
1393 static void clear_memalloc(int memalloc)
1394 {
1395         if (memalloc)
1396                 current->flags &= ~PF_MEMALLOC;
1397 }
1398
1399 static ssize_t read_file(struct nandsim *ns, struct file *file, void *buf, size_t count, loff_t pos)
1400 {
1401         ssize_t tx;
1402         int err, memalloc;
1403
1404         err = get_pages(ns, file, count, pos);
1405         if (err)
1406                 return err;
1407         memalloc = set_memalloc();
1408         tx = kernel_read(file, pos, buf, count);
1409         clear_memalloc(memalloc);
1410         put_pages(ns);
1411         return tx;
1412 }
1413
1414 static ssize_t write_file(struct nandsim *ns, struct file *file, void *buf, size_t count, loff_t pos)
1415 {
1416         ssize_t tx;
1417         int err, memalloc;
1418
1419         err = get_pages(ns, file, count, pos);
1420         if (err)
1421                 return err;
1422         memalloc = set_memalloc();
1423         tx = kernel_write(file, buf, count, pos);
1424         clear_memalloc(memalloc);
1425         put_pages(ns);
1426         return tx;
1427 }
1428
1429 /*
1430  * Returns a pointer to the current page.
1431  */
1432 static inline union ns_mem *NS_GET_PAGE(struct nandsim *ns)
1433 {
1434         return &(ns->pages[ns->regs.row]);
1435 }
1436
1437 /*
1438  * Retuns a pointer to the current byte, within the current page.
1439  */
1440 static inline u_char *NS_PAGE_BYTE_OFF(struct nandsim *ns)
1441 {
1442         return NS_GET_PAGE(ns)->byte + ns->regs.column + ns->regs.off;
1443 }
1444
1445 int do_read_error(struct nandsim *ns, int num)
1446 {
1447         unsigned int page_no = ns->regs.row;
1448
1449         if (read_error(page_no)) {
1450                 prandom_bytes(ns->buf.byte, num);
1451                 NS_WARN("simulating read error in page %u\n", page_no);
1452                 return 1;
1453         }
1454         return 0;
1455 }
1456
1457 void do_bit_flips(struct nandsim *ns, int num)
1458 {
1459         if (bitflips && prandom_u32() < (1 << 22)) {
1460                 int flips = 1;
1461                 if (bitflips > 1)
1462                         flips = (prandom_u32() % (int) bitflips) + 1;
1463                 while (flips--) {
1464                         int pos = prandom_u32() % (num * 8);
1465                         ns->buf.byte[pos / 8] ^= (1 << (pos % 8));
1466                         NS_WARN("read_page: flipping bit %d in page %d "
1467                                 "reading from %d ecc: corrected=%u failed=%u\n",
1468                                 pos, ns->regs.row, ns->regs.column + ns->regs.off,
1469                                 nsmtd->ecc_stats.corrected, nsmtd->ecc_stats.failed);
1470                 }
1471         }
1472 }
1473
1474 /*
1475  * Fill the NAND buffer with data read from the specified page.
1476  */
1477 static void read_page(struct nandsim *ns, int num)
1478 {
1479         union ns_mem *mypage;
1480
1481         if (ns->cfile) {
1482                 if (!ns->pages_written[ns->regs.row]) {
1483                         NS_DBG("read_page: page %d not written\n", ns->regs.row);
1484                         memset(ns->buf.byte, 0xFF, num);
1485                 } else {
1486                         loff_t pos;
1487                         ssize_t tx;
1488
1489                         NS_DBG("read_page: page %d written, reading from %d\n",
1490                                 ns->regs.row, ns->regs.column + ns->regs.off);
1491                         if (do_read_error(ns, num))
1492                                 return;
1493                         pos = (loff_t)ns->regs.row * ns->geom.pgszoob + ns->regs.column + ns->regs.off;
1494                         tx = read_file(ns, ns->cfile, ns->buf.byte, num, pos);
1495                         if (tx != num) {
1496                                 NS_ERR("read_page: read error for page %d ret %ld\n", ns->regs.row, (long)tx);
1497                                 return;
1498                         }
1499                         do_bit_flips(ns, num);
1500                 }
1501                 return;
1502         }
1503
1504         mypage = NS_GET_PAGE(ns);
1505         if (mypage->byte == NULL) {
1506                 NS_DBG("read_page: page %d not allocated\n", ns->regs.row);
1507                 memset(ns->buf.byte, 0xFF, num);
1508         } else {
1509                 NS_DBG("read_page: page %d allocated, reading from %d\n",
1510                         ns->regs.row, ns->regs.column + ns->regs.off);
1511                 if (do_read_error(ns, num))
1512                         return;
1513                 memcpy(ns->buf.byte, NS_PAGE_BYTE_OFF(ns), num);
1514                 do_bit_flips(ns, num);
1515         }
1516 }
1517
1518 /*
1519  * Erase all pages in the specified sector.
1520  */
1521 static void erase_sector(struct nandsim *ns)
1522 {
1523         union ns_mem *mypage;
1524         int i;
1525
1526         if (ns->cfile) {
1527                 for (i = 0; i < ns->geom.pgsec; i++)
1528                         if (ns->pages_written[ns->regs.row + i]) {
1529                                 NS_DBG("erase_sector: freeing page %d\n", ns->regs.row + i);
1530                                 ns->pages_written[ns->regs.row + i] = 0;
1531                         }
1532                 return;
1533         }
1534
1535         mypage = NS_GET_PAGE(ns);
1536         for (i = 0; i < ns->geom.pgsec; i++) {
1537                 if (mypage->byte != NULL) {
1538                         NS_DBG("erase_sector: freeing page %d\n", ns->regs.row+i);
1539                         kmem_cache_free(ns->nand_pages_slab, mypage->byte);
1540                         mypage->byte = NULL;
1541                 }
1542                 mypage++;
1543         }
1544 }
1545
1546 /*
1547  * Program the specified page with the contents from the NAND buffer.
1548  */
1549 static int prog_page(struct nandsim *ns, int num)
1550 {
1551         int i;
1552         union ns_mem *mypage;
1553         u_char *pg_off;
1554
1555         if (ns->cfile) {
1556                 loff_t off;
1557                 ssize_t tx;
1558                 int all;
1559
1560                 NS_DBG("prog_page: writing page %d\n", ns->regs.row);
1561                 pg_off = ns->file_buf + ns->regs.column + ns->regs.off;
1562                 off = (loff_t)ns->regs.row * ns->geom.pgszoob + ns->regs.column + ns->regs.off;
1563                 if (!ns->pages_written[ns->regs.row]) {
1564                         all = 1;
1565                         memset(ns->file_buf, 0xff, ns->geom.pgszoob);
1566                 } else {
1567                         all = 0;
1568                         tx = read_file(ns, ns->cfile, pg_off, num, off);
1569                         if (tx != num) {
1570                                 NS_ERR("prog_page: read error for page %d ret %ld\n", ns->regs.row, (long)tx);
1571                                 return -1;
1572                         }
1573                 }
1574                 for (i = 0; i < num; i++)
1575                         pg_off[i] &= ns->buf.byte[i];
1576                 if (all) {
1577                         loff_t pos = (loff_t)ns->regs.row * ns->geom.pgszoob;
1578                         tx = write_file(ns, ns->cfile, ns->file_buf, ns->geom.pgszoob, pos);
1579                         if (tx != ns->geom.pgszoob) {
1580                                 NS_ERR("prog_page: write error for page %d ret %ld\n", ns->regs.row, (long)tx);
1581                                 return -1;
1582                         }
1583                         ns->pages_written[ns->regs.row] = 1;
1584                 } else {
1585                         tx = write_file(ns, ns->cfile, pg_off, num, off);
1586                         if (tx != num) {
1587                                 NS_ERR("prog_page: write error for page %d ret %ld\n", ns->regs.row, (long)tx);
1588                                 return -1;
1589                         }
1590                 }
1591                 return 0;
1592         }
1593
1594         mypage = NS_GET_PAGE(ns);
1595         if (mypage->byte == NULL) {
1596                 NS_DBG("prog_page: allocating page %d\n", ns->regs.row);
1597                 /*
1598                  * We allocate memory with GFP_NOFS because a flash FS may
1599                  * utilize this. If it is holding an FS lock, then gets here,
1600                  * then kernel memory alloc runs writeback which goes to the FS
1601                  * again and deadlocks. This was seen in practice.
1602                  */
1603                 mypage->byte = kmem_cache_alloc(ns->nand_pages_slab, GFP_NOFS);
1604                 if (mypage->byte == NULL) {
1605                         NS_ERR("prog_page: error allocating memory for page %d\n", ns->regs.row);
1606                         return -1;
1607                 }
1608                 memset(mypage->byte, 0xFF, ns->geom.pgszoob);
1609         }
1610
1611         pg_off = NS_PAGE_BYTE_OFF(ns);
1612         for (i = 0; i < num; i++)
1613                 pg_off[i] &= ns->buf.byte[i];
1614
1615         return 0;
1616 }
1617
1618 /*
1619  * If state has any action bit, perform this action.
1620  *
1621  * RETURNS: 0 if success, -1 if error.
1622  */
1623 static int do_state_action(struct nandsim *ns, uint32_t action)
1624 {
1625         int num;
1626         int busdiv = ns->busw == 8 ? 1 : 2;
1627         unsigned int erase_block_no, page_no;
1628
1629         action &= ACTION_MASK;
1630
1631         /* Check that page address input is correct */
1632         if (action != ACTION_SECERASE && ns->regs.row >= ns->geom.pgnum) {
1633                 NS_WARN("do_state_action: wrong page number (%#x)\n", ns->regs.row);
1634                 return -1;
1635         }
1636
1637         switch (action) {
1638
1639         case ACTION_CPY:
1640                 /*
1641                  * Copy page data to the internal buffer.
1642                  */
1643
1644                 /* Column shouldn't be very large */
1645                 if (ns->regs.column >= (ns->geom.pgszoob - ns->regs.off)) {
1646                         NS_ERR("do_state_action: column number is too large\n");
1647                         break;
1648                 }
1649                 num = ns->geom.pgszoob - ns->regs.off - ns->regs.column;
1650                 read_page(ns, num);
1651
1652                 NS_DBG("do_state_action: (ACTION_CPY:) copy %d bytes to int buf, raw offset %d\n",
1653                         num, NS_RAW_OFFSET(ns) + ns->regs.off);
1654
1655                 if (ns->regs.off == 0)
1656                         NS_LOG("read page %d\n", ns->regs.row);
1657                 else if (ns->regs.off < ns->geom.pgsz)
1658                         NS_LOG("read page %d (second half)\n", ns->regs.row);
1659                 else
1660                         NS_LOG("read OOB of page %d\n", ns->regs.row);
1661
1662                 NS_UDELAY(access_delay);
1663                 NS_UDELAY(input_cycle * ns->geom.pgsz / 1000 / busdiv);
1664
1665                 break;
1666
1667         case ACTION_SECERASE:
1668                 /*
1669                  * Erase sector.
1670                  */
1671
1672                 if (ns->lines.wp) {
1673                         NS_ERR("do_state_action: device is write-protected, ignore sector erase\n");
1674                         return -1;
1675                 }
1676
1677                 if (ns->regs.row >= ns->geom.pgnum - ns->geom.pgsec
1678                         || (ns->regs.row & ~(ns->geom.secsz - 1))) {
1679                         NS_ERR("do_state_action: wrong sector address (%#x)\n", ns->regs.row);
1680                         return -1;
1681                 }
1682
1683                 ns->regs.row = (ns->regs.row <<
1684                                 8 * (ns->geom.pgaddrbytes - ns->geom.secaddrbytes)) | ns->regs.column;
1685                 ns->regs.column = 0;
1686
1687                 erase_block_no = ns->regs.row >> (ns->geom.secshift - ns->geom.pgshift);
1688
1689                 NS_DBG("do_state_action: erase sector at address %#x, off = %d\n",
1690                                 ns->regs.row, NS_RAW_OFFSET(ns));
1691                 NS_LOG("erase sector %u\n", erase_block_no);
1692
1693                 erase_sector(ns);
1694
1695                 NS_MDELAY(erase_delay);
1696
1697                 if (erase_block_wear)
1698                         update_wear(erase_block_no);
1699
1700                 if (erase_error(erase_block_no)) {
1701                         NS_WARN("simulating erase failure in erase block %u\n", erase_block_no);
1702                         return -1;
1703                 }
1704
1705                 break;
1706
1707         case ACTION_PRGPAGE:
1708                 /*
1709                  * Program page - move internal buffer data to the page.
1710                  */
1711
1712                 if (ns->lines.wp) {
1713                         NS_WARN("do_state_action: device is write-protected, programm\n");
1714                         return -1;
1715                 }
1716
1717                 num = ns->geom.pgszoob - ns->regs.off - ns->regs.column;
1718                 if (num != ns->regs.count) {
1719                         NS_ERR("do_state_action: too few bytes were input (%d instead of %d)\n",
1720                                         ns->regs.count, num);
1721                         return -1;
1722                 }
1723
1724                 if (prog_page(ns, num) == -1)
1725                         return -1;
1726
1727                 page_no = ns->regs.row;
1728
1729                 NS_DBG("do_state_action: copy %d bytes from int buf to (%#x, %#x), raw off = %d\n",
1730                         num, ns->regs.row, ns->regs.column, NS_RAW_OFFSET(ns) + ns->regs.off);
1731                 NS_LOG("programm page %d\n", ns->regs.row);
1732
1733                 NS_UDELAY(programm_delay);
1734                 NS_UDELAY(output_cycle * ns->geom.pgsz / 1000 / busdiv);
1735
1736                 if (write_error(page_no)) {
1737                         NS_WARN("simulating write failure in page %u\n", page_no);
1738                         return -1;
1739                 }
1740
1741                 break;
1742
1743         case ACTION_ZEROOFF:
1744                 NS_DBG("do_state_action: set internal offset to 0\n");
1745                 ns->regs.off = 0;
1746                 break;
1747
1748         case ACTION_HALFOFF:
1749                 if (!(ns->options & OPT_PAGE512_8BIT)) {
1750                         NS_ERR("do_state_action: BUG! can't skip half of page for non-512"
1751                                 "byte page size 8x chips\n");
1752                         return -1;
1753                 }
1754                 NS_DBG("do_state_action: set internal offset to %d\n", ns->geom.pgsz/2);
1755                 ns->regs.off = ns->geom.pgsz/2;
1756                 break;
1757
1758         case ACTION_OOBOFF:
1759                 NS_DBG("do_state_action: set internal offset to %d\n", ns->geom.pgsz);
1760                 ns->regs.off = ns->geom.pgsz;
1761                 break;
1762
1763         default:
1764                 NS_DBG("do_state_action: BUG! unknown action\n");
1765         }
1766
1767         return 0;
1768 }
1769
1770 /*
1771  * Switch simulator's state.
1772  */
1773 static void switch_state(struct nandsim *ns)
1774 {
1775         if (ns->op) {
1776                 /*
1777                  * The current operation have already been identified.
1778                  * Just follow the states chain.
1779                  */
1780
1781                 ns->stateidx += 1;
1782                 ns->state = ns->nxstate;
1783                 ns->nxstate = ns->op[ns->stateidx + 1];
1784
1785                 NS_DBG("switch_state: operation is known, switch to the next state, "
1786                         "state: %s, nxstate: %s\n",
1787                         get_state_name(ns->state), get_state_name(ns->nxstate));
1788
1789                 /* See, whether we need to do some action */
1790                 if ((ns->state & ACTION_MASK) && do_state_action(ns, ns->state) < 0) {
1791                         switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1792                         return;
1793                 }
1794
1795         } else {
1796                 /*
1797                  * We don't yet know which operation we perform.
1798                  * Try to identify it.
1799                  */
1800
1801                 /*
1802                  *  The only event causing the switch_state function to
1803                  *  be called with yet unknown operation is new command.
1804                  */
1805                 ns->state = get_state_by_command(ns->regs.command);
1806
1807                 NS_DBG("switch_state: operation is unknown, try to find it\n");
1808
1809                 if (find_operation(ns, 0) != 0)
1810                         return;
1811
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
1818         /* For 16x devices column means the page offset in words */
1819         if ((ns->nxstate & STATE_ADDR_MASK) && ns->busw == 16) {
1820                 NS_DBG("switch_state: double the column number for 16x device\n");
1821                 ns->regs.column <<= 1;
1822         }
1823
1824         if (NS_STATE(ns->nxstate) == STATE_READY) {
1825                 /*
1826                  * The current state is the last. Return to STATE_READY
1827                  */
1828
1829                 u_char status = NS_STATUS_OK(ns);
1830
1831                 /* In case of data states, see if all bytes were input/output */
1832                 if ((ns->state & (STATE_DATAIN_MASK | STATE_DATAOUT_MASK))
1833                         && ns->regs.count != ns->regs.num) {
1834                         NS_WARN("switch_state: not all bytes were processed, %d left\n",
1835                                         ns->regs.num - ns->regs.count);
1836                         status = NS_STATUS_FAILED(ns);
1837                 }
1838
1839                 NS_DBG("switch_state: operation complete, switch to STATE_READY state\n");
1840
1841                 switch_to_ready_state(ns, status);
1842
1843                 return;
1844         } else if (ns->nxstate & (STATE_DATAIN_MASK | STATE_DATAOUT_MASK)) {
1845                 /*
1846                  * If the next state is data input/output, switch to it now
1847                  */
1848
1849                 ns->state      = ns->nxstate;
1850                 ns->nxstate    = ns->op[++ns->stateidx + 1];
1851                 ns->regs.num   = ns->regs.count = 0;
1852
1853                 NS_DBG("switch_state: the next state is data I/O, switch, "
1854                         "state: %s, nxstate: %s\n",
1855                         get_state_name(ns->state), get_state_name(ns->nxstate));
1856
1857                 /*
1858                  * Set the internal register to the count of bytes which
1859                  * are expected to be input or output
1860                  */
1861                 switch (NS_STATE(ns->state)) {
1862                         case STATE_DATAIN:
1863                         case STATE_DATAOUT:
1864                                 ns->regs.num = ns->geom.pgszoob - ns->regs.off - ns->regs.column;
1865                                 break;
1866
1867                         case STATE_DATAOUT_ID:
1868                                 ns->regs.num = ns->geom.idbytes;
1869                                 break;
1870
1871                         case STATE_DATAOUT_STATUS:
1872                         case STATE_DATAOUT_STATUS_M:
1873                                 ns->regs.count = ns->regs.num = 0;
1874                                 break;
1875
1876                         default:
1877                                 NS_ERR("switch_state: BUG! unknown data state\n");
1878                 }
1879
1880         } else if (ns->nxstate & STATE_ADDR_MASK) {
1881                 /*
1882                  * If the next state is address input, set the internal
1883                  * register to the number of expected address bytes
1884                  */
1885
1886                 ns->regs.count = 0;
1887
1888                 switch (NS_STATE(ns->nxstate)) {
1889                         case STATE_ADDR_PAGE:
1890                                 ns->regs.num = ns->geom.pgaddrbytes;
1891
1892                                 break;
1893                         case STATE_ADDR_SEC:
1894                                 ns->regs.num = ns->geom.secaddrbytes;
1895                                 break;
1896
1897                         case STATE_ADDR_ZERO:
1898                                 ns->regs.num = 1;
1899                                 break;
1900
1901                         case STATE_ADDR_COLUMN:
1902                                 /* Column address is always 2 bytes */
1903                                 ns->regs.num = ns->geom.pgaddrbytes - ns->geom.secaddrbytes;
1904                                 break;
1905
1906                         default:
1907                                 NS_ERR("switch_state: BUG! unknown address state\n");
1908                 }
1909         } else {
1910                 /*
1911                  * Just reset internal counters.
1912                  */
1913
1914                 ns->regs.num = 0;
1915                 ns->regs.count = 0;
1916         }
1917 }
1918
1919 static u_char ns_nand_read_byte(struct mtd_info *mtd)
1920 {
1921         struct nandsim *ns = ((struct nand_chip *)mtd->priv)->priv;
1922         u_char outb = 0x00;
1923
1924         /* Sanity and correctness checks */
1925         if (!ns->lines.ce) {
1926                 NS_ERR("read_byte: chip is disabled, return %#x\n", (uint)outb);
1927                 return outb;
1928         }
1929         if (ns->lines.ale || ns->lines.cle) {
1930                 NS_ERR("read_byte: ALE or CLE pin is high, return %#x\n", (uint)outb);
1931                 return outb;
1932         }
1933         if (!(ns->state & STATE_DATAOUT_MASK)) {
1934                 NS_WARN("read_byte: unexpected data output cycle, state is %s "
1935                         "return %#x\n", get_state_name(ns->state), (uint)outb);
1936                 return outb;
1937         }
1938
1939         /* Status register may be read as many times as it is wanted */
1940         if (NS_STATE(ns->state) == STATE_DATAOUT_STATUS) {
1941                 NS_DBG("read_byte: return %#x status\n", ns->regs.status);
1942                 return ns->regs.status;
1943         }
1944
1945         /* Check if there is any data in the internal buffer which may be read */
1946         if (ns->regs.count == ns->regs.num) {
1947                 NS_WARN("read_byte: no more data to output, return %#x\n", (uint)outb);
1948                 return outb;
1949         }
1950
1951         switch (NS_STATE(ns->state)) {
1952                 case STATE_DATAOUT:
1953                         if (ns->busw == 8) {
1954                                 outb = ns->buf.byte[ns->regs.count];
1955                                 ns->regs.count += 1;
1956                         } else {
1957                                 outb = (u_char)cpu_to_le16(ns->buf.word[ns->regs.count >> 1]);
1958                                 ns->regs.count += 2;
1959                         }
1960                         break;
1961                 case STATE_DATAOUT_ID:
1962                         NS_DBG("read_byte: read ID byte %d, total = %d\n", ns->regs.count, ns->regs.num);
1963                         outb = ns->ids[ns->regs.count];
1964                         ns->regs.count += 1;
1965                         break;
1966                 default:
1967                         BUG();
1968         }
1969
1970         if (ns->regs.count == ns->regs.num) {
1971                 NS_DBG("read_byte: all bytes were read\n");
1972
1973                 if (NS_STATE(ns->nxstate) == STATE_READY)
1974                         switch_state(ns);
1975         }
1976
1977         return outb;
1978 }
1979
1980 static void ns_nand_write_byte(struct mtd_info *mtd, u_char byte)
1981 {
1982         struct nandsim *ns = ((struct nand_chip *)mtd->priv)->priv;
1983
1984         /* Sanity and correctness checks */
1985         if (!ns->lines.ce) {
1986                 NS_ERR("write_byte: chip is disabled, ignore write\n");
1987                 return;
1988         }
1989         if (ns->lines.ale && ns->lines.cle) {
1990                 NS_ERR("write_byte: ALE and CLE pins are high simultaneously, ignore write\n");
1991                 return;
1992         }
1993
1994         if (ns->lines.cle == 1) {
1995                 /*
1996                  * The byte written is a command.
1997                  */
1998
1999                 if (byte == NAND_CMD_RESET) {
2000                         NS_LOG("reset chip\n");
2001                         switch_to_ready_state(ns, NS_STATUS_OK(ns));
2002                         return;
2003                 }
2004
2005                 /* Check that the command byte is correct */
2006                 if (check_command(byte)) {
2007                         NS_ERR("write_byte: unknown command %#x\n", (uint)byte);
2008                         return;
2009                 }
2010
2011                 if (NS_STATE(ns->state) == STATE_DATAOUT_STATUS
2012                         || NS_STATE(ns->state) == STATE_DATAOUT_STATUS_M
2013                         || NS_STATE(ns->state) == STATE_DATAOUT) {
2014                         int row = ns->regs.row;
2015
2016                         switch_state(ns);
2017                         if (byte == NAND_CMD_RNDOUT)
2018                                 ns->regs.row = row;
2019                 }
2020
2021                 /* Check if chip is expecting command */
2022                 if (NS_STATE(ns->nxstate) != STATE_UNKNOWN && !(ns->nxstate & STATE_CMD_MASK)) {
2023                         /* Do not warn if only 2 id bytes are read */
2024                         if (!(ns->regs.command == NAND_CMD_READID &&
2025                             NS_STATE(ns->state) == STATE_DATAOUT_ID && ns->regs.count == 2)) {
2026                                 /*
2027                                  * We are in situation when something else (not command)
2028                                  * was expected but command was input. In this case ignore
2029                                  * previous command(s)/state(s) and accept the last one.
2030                                  */
2031                                 NS_WARN("write_byte: command (%#x) wasn't expected, expected state is %s, "
2032                                         "ignore previous states\n", (uint)byte, get_state_name(ns->nxstate));
2033                         }
2034                         switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2035                 }
2036
2037                 NS_DBG("command byte corresponding to %s state accepted\n",
2038                         get_state_name(get_state_by_command(byte)));
2039                 ns->regs.command = byte;
2040                 switch_state(ns);
2041
2042         } else if (ns->lines.ale == 1) {
2043                 /*
2044                  * The byte written is an address.
2045                  */
2046
2047                 if (NS_STATE(ns->nxstate) == STATE_UNKNOWN) {
2048
2049                         NS_DBG("write_byte: operation isn't known yet, identify it\n");
2050
2051                         if (find_operation(ns, 1) < 0)
2052                                 return;
2053
2054                         if ((ns->state & ACTION_MASK) && do_state_action(ns, ns->state) < 0) {
2055                                 switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2056                                 return;
2057                         }
2058
2059                         ns->regs.count = 0;
2060                         switch (NS_STATE(ns->nxstate)) {
2061                                 case STATE_ADDR_PAGE:
2062                                         ns->regs.num = ns->geom.pgaddrbytes;
2063                                         break;
2064                                 case STATE_ADDR_SEC:
2065                                         ns->regs.num = ns->geom.secaddrbytes;
2066                                         break;
2067                                 case STATE_ADDR_ZERO:
2068                                         ns->regs.num = 1;
2069                                         break;
2070                                 default:
2071                                         BUG();
2072                         }
2073                 }
2074
2075                 /* Check that chip is expecting address */
2076                 if (!(ns->nxstate & STATE_ADDR_MASK)) {
2077                         NS_ERR("write_byte: address (%#x) isn't expected, expected state is %s, "
2078                                 "switch to STATE_READY\n", (uint)byte, get_state_name(ns->nxstate));
2079                         switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2080                         return;
2081                 }
2082
2083                 /* Check if this is expected byte */
2084                 if (ns->regs.count == ns->regs.num) {
2085                         NS_ERR("write_byte: no more address bytes expected\n");
2086                         switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2087                         return;
2088                 }
2089
2090                 accept_addr_byte(ns, byte);
2091
2092                 ns->regs.count += 1;
2093
2094                 NS_DBG("write_byte: address byte %#x was accepted (%d bytes input, %d expected)\n",
2095                                 (uint)byte, ns->regs.count, ns->regs.num);
2096
2097                 if (ns->regs.count == ns->regs.num) {
2098                         NS_DBG("address (%#x, %#x) is accepted\n", ns->regs.row, ns->regs.column);
2099                         switch_state(ns);
2100                 }
2101
2102         } else {
2103                 /*
2104                  * The byte written is an input data.
2105                  */
2106
2107                 /* Check that chip is expecting data input */
2108                 if (!(ns->state & STATE_DATAIN_MASK)) {
2109                         NS_ERR("write_byte: data input (%#x) isn't expected, state is %s, "
2110                                 "switch to %s\n", (uint)byte,
2111                                 get_state_name(ns->state), get_state_name(STATE_READY));
2112                         switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2113                         return;
2114                 }
2115
2116                 /* Check if this is expected byte */
2117                 if (ns->regs.count == ns->regs.num) {
2118                         NS_WARN("write_byte: %u input bytes has already been accepted, ignore write\n",
2119                                         ns->regs.num);
2120                         return;
2121                 }
2122
2123                 if (ns->busw == 8) {
2124                         ns->buf.byte[ns->regs.count] = byte;
2125                         ns->regs.count += 1;
2126                 } else {
2127                         ns->buf.word[ns->regs.count >> 1] = cpu_to_le16((uint16_t)byte);
2128                         ns->regs.count += 2;
2129                 }
2130         }
2131
2132         return;
2133 }
2134
2135 static void ns_hwcontrol(struct mtd_info *mtd, int cmd, unsigned int bitmask)
2136 {
2137         struct nandsim *ns = ((struct nand_chip *)mtd->priv)->priv;
2138
2139         ns->lines.cle = bitmask & NAND_CLE ? 1 : 0;
2140         ns->lines.ale = bitmask & NAND_ALE ? 1 : 0;
2141         ns->lines.ce = bitmask & NAND_NCE ? 1 : 0;
2142
2143         if (cmd != NAND_CMD_NONE)
2144                 ns_nand_write_byte(mtd, cmd);
2145 }
2146
2147 static int ns_device_ready(struct mtd_info *mtd)
2148 {
2149         NS_DBG("device_ready\n");
2150         return 1;
2151 }
2152
2153 static uint16_t ns_nand_read_word(struct mtd_info *mtd)
2154 {
2155         struct nand_chip *chip = (struct nand_chip *)mtd->priv;
2156
2157         NS_DBG("read_word\n");
2158
2159         return chip->read_byte(mtd) | (chip->read_byte(mtd) << 8);
2160 }
2161
2162 static void ns_nand_write_buf(struct mtd_info *mtd, const u_char *buf, int len)
2163 {
2164         struct nandsim *ns = ((struct nand_chip *)mtd->priv)->priv;
2165
2166         /* Check that chip is expecting data input */
2167         if (!(ns->state & STATE_DATAIN_MASK)) {
2168                 NS_ERR("write_buf: data input isn't expected, state is %s, "
2169                         "switch to STATE_READY\n", get_state_name(ns->state));
2170                 switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2171                 return;
2172         }
2173
2174         /* Check if these are expected bytes */
2175         if (ns->regs.count + len > ns->regs.num) {
2176                 NS_ERR("write_buf: too many input bytes\n");
2177                 switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2178                 return;
2179         }
2180
2181         memcpy(ns->buf.byte + ns->regs.count, buf, len);
2182         ns->regs.count += len;
2183
2184         if (ns->regs.count == ns->regs.num) {
2185                 NS_DBG("write_buf: %d bytes were written\n", ns->regs.count);
2186         }
2187 }
2188
2189 static void ns_nand_read_buf(struct mtd_info *mtd, u_char *buf, int len)
2190 {
2191         struct nandsim *ns = ((struct nand_chip *)mtd->priv)->priv;
2192
2193         /* Sanity and correctness checks */
2194         if (!ns->lines.ce) {
2195                 NS_ERR("read_buf: chip is disabled\n");
2196                 return;
2197         }
2198         if (ns->lines.ale || ns->lines.cle) {
2199                 NS_ERR("read_buf: ALE or CLE pin is high\n");
2200                 return;
2201         }
2202         if (!(ns->state & STATE_DATAOUT_MASK)) {
2203                 NS_WARN("read_buf: unexpected data output cycle, current state is %s\n",
2204                         get_state_name(ns->state));
2205                 return;
2206         }
2207
2208         if (NS_STATE(ns->state) != STATE_DATAOUT) {
2209                 int i;
2210
2211                 for (i = 0; i < len; i++)
2212                         buf[i] = ((struct nand_chip *)mtd->priv)->read_byte(mtd);
2213
2214                 return;
2215         }
2216
2217         /* Check if these are expected bytes */
2218         if (ns->regs.count + len > ns->regs.num) {
2219                 NS_ERR("read_buf: too many bytes to read\n");
2220                 switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2221                 return;
2222         }
2223
2224         memcpy(buf, ns->buf.byte + ns->regs.count, len);
2225         ns->regs.count += len;
2226
2227         if (ns->regs.count == ns->regs.num) {
2228                 if (NS_STATE(ns->nxstate) == STATE_READY)
2229                         switch_state(ns);
2230         }
2231
2232         return;
2233 }
2234
2235 /*
2236  * Module initialization function
2237  */
2238 static int __init ns_init_module(void)
2239 {
2240         struct nand_chip *chip;
2241         struct nandsim *nand;
2242         int retval = -ENOMEM, i;
2243
2244         if (bus_width != 8 && bus_width != 16) {
2245                 NS_ERR("wrong bus width (%d), use only 8 or 16\n", bus_width);
2246                 return -EINVAL;
2247         }
2248
2249         /* Allocate and initialize mtd_info, nand_chip and nandsim structures */
2250         nsmtd = kzalloc(sizeof(struct mtd_info) + sizeof(struct nand_chip)
2251                                 + sizeof(struct nandsim), GFP_KERNEL);
2252         if (!nsmtd) {
2253                 NS_ERR("unable to allocate core structures.\n");
2254                 return -ENOMEM;
2255         }
2256         chip        = (struct nand_chip *)(nsmtd + 1);
2257         nsmtd->priv = (void *)chip;
2258         nand        = (struct nandsim *)(chip + 1);
2259         chip->priv  = (void *)nand;
2260
2261         /*
2262          * Register simulator's callbacks.
2263          */
2264         chip->cmd_ctrl   = ns_hwcontrol;
2265         chip->read_byte  = ns_nand_read_byte;
2266         chip->dev_ready  = ns_device_ready;
2267         chip->write_buf  = ns_nand_write_buf;
2268         chip->read_buf   = ns_nand_read_buf;
2269         chip->read_word  = ns_nand_read_word;
2270         chip->ecc.mode   = NAND_ECC_SOFT;
2271         /* The NAND_SKIP_BBTSCAN option is necessary for 'overridesize' */
2272         /* and 'badblocks' parameters to work */
2273         chip->options   |= NAND_SKIP_BBTSCAN;
2274
2275         switch (bbt) {
2276         case 2:
2277                  chip->bbt_options |= NAND_BBT_NO_OOB;
2278         case 1:
2279                  chip->bbt_options |= NAND_BBT_USE_FLASH;
2280         case 0:
2281                 break;
2282         default:
2283                 NS_ERR("bbt has to be 0..2\n");
2284                 retval = -EINVAL;
2285                 goto error;
2286         }
2287         /*
2288          * Perform minimum nandsim structure initialization to handle
2289          * the initial ID read command correctly
2290          */
2291         if (third_id_byte != 0xFF || fourth_id_byte != 0xFF)
2292                 nand->geom.idbytes = 4;
2293         else
2294                 nand->geom.idbytes = 2;
2295         nand->regs.status = NS_STATUS_OK(nand);
2296         nand->nxstate = STATE_UNKNOWN;
2297         nand->options |= OPT_PAGE512; /* temporary value */
2298         nand->ids[0] = first_id_byte;
2299         nand->ids[1] = second_id_byte;
2300         nand->ids[2] = third_id_byte;
2301         nand->ids[3] = fourth_id_byte;
2302         if (bus_width == 16) {
2303                 nand->busw = 16;
2304                 chip->options |= NAND_BUSWIDTH_16;
2305         }
2306
2307         nsmtd->owner = THIS_MODULE;
2308
2309         if ((retval = parse_weakblocks()) != 0)
2310                 goto error;
2311
2312         if ((retval = parse_weakpages()) != 0)
2313                 goto error;
2314
2315         if ((retval = parse_gravepages()) != 0)
2316                 goto error;
2317
2318         retval = nand_scan_ident(nsmtd, 1, NULL);
2319         if (retval) {
2320                 NS_ERR("cannot scan NAND Simulator device\n");
2321                 if (retval > 0)
2322                         retval = -ENXIO;
2323                 goto error;
2324         }
2325
2326         if (bch) {
2327                 unsigned int eccsteps, eccbytes;
2328                 if (!mtd_nand_has_bch()) {
2329                         NS_ERR("BCH ECC support is disabled\n");
2330                         retval = -EINVAL;
2331                         goto error;
2332                 }
2333                 /* use 512-byte ecc blocks */
2334                 eccsteps = nsmtd->writesize/512;
2335                 eccbytes = (bch*13+7)/8;
2336                 /* do not bother supporting small page devices */
2337                 if ((nsmtd->oobsize < 64) || !eccsteps) {
2338                         NS_ERR("bch not available on small page devices\n");
2339                         retval = -EINVAL;
2340                         goto error;
2341                 }
2342                 if ((eccbytes*eccsteps+2) > nsmtd->oobsize) {
2343                         NS_ERR("invalid bch value %u\n", bch);
2344                         retval = -EINVAL;
2345                         goto error;
2346                 }
2347                 chip->ecc.mode = NAND_ECC_SOFT_BCH;
2348                 chip->ecc.size = 512;
2349                 chip->ecc.bytes = eccbytes;
2350                 NS_INFO("using %u-bit/%u bytes BCH ECC\n", bch, chip->ecc.size);
2351         }
2352
2353         retval = nand_scan_tail(nsmtd);
2354         if (retval) {
2355                 NS_ERR("can't register NAND Simulator\n");
2356                 if (retval > 0)
2357                         retval = -ENXIO;
2358                 goto error;
2359         }
2360
2361         if (overridesize) {
2362                 uint64_t new_size = (uint64_t)nsmtd->erasesize << overridesize;
2363                 if (new_size >> overridesize != nsmtd->erasesize) {
2364                         NS_ERR("overridesize is too big\n");
2365                         retval = -EINVAL;
2366                         goto err_exit;
2367                 }
2368                 /* N.B. This relies on nand_scan not doing anything with the size before we change it */
2369                 nsmtd->size = new_size;
2370                 chip->chipsize = new_size;
2371                 chip->chip_shift = ffs(nsmtd->erasesize) + overridesize - 1;
2372                 chip->pagemask = (chip->chipsize >> chip->page_shift) - 1;
2373         }
2374
2375         if ((retval = setup_wear_reporting(nsmtd)) != 0)
2376                 goto err_exit;
2377
2378         if ((retval = nandsim_debugfs_create(nand)) != 0)
2379                 goto err_exit;
2380
2381         if ((retval = init_nandsim(nsmtd)) != 0)
2382                 goto err_exit;
2383
2384         if ((retval = nand_default_bbt(nsmtd)) != 0)
2385                 goto err_exit;
2386
2387         if ((retval = parse_badblocks(nand, nsmtd)) != 0)
2388                 goto err_exit;
2389
2390         /* Register NAND partitions */
2391         retval = mtd_device_register(nsmtd, &nand->partitions[0],
2392                                      nand->nbparts);
2393         if (retval != 0)
2394                 goto err_exit;
2395
2396         return 0;
2397
2398 err_exit:
2399         free_nandsim(nand);
2400         nand_release(nsmtd);
2401         for (i = 0;i < ARRAY_SIZE(nand->partitions); ++i)
2402                 kfree(nand->partitions[i].name);
2403 error:
2404         kfree(nsmtd);
2405         free_lists();
2406
2407         return retval;
2408 }
2409
2410 module_init(ns_init_module);
2411
2412 /*
2413  * Module clean-up function
2414  */
2415 static void __exit ns_cleanup_module(void)
2416 {
2417         struct nandsim *ns = ((struct nand_chip *)nsmtd->priv)->priv;
2418         int i;
2419
2420         nandsim_debugfs_remove(ns);
2421         free_nandsim(ns);    /* Free nandsim private resources */
2422         nand_release(nsmtd); /* Unregister driver */
2423         for (i = 0;i < ARRAY_SIZE(ns->partitions); ++i)
2424                 kfree(ns->partitions[i].name);
2425         kfree(nsmtd);        /* Free other structures */
2426         free_lists();
2427 }
2428
2429 module_exit(ns_cleanup_module);
2430
2431 MODULE_LICENSE ("GPL");
2432 MODULE_AUTHOR ("Artem B. Bityuckiy");
2433 MODULE_DESCRIPTION ("The NAND flash simulator");